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Sample records for 16-slice mdct arthrography

  1. The feasibility of a 64-slice MDCT for detection of the Adamkiewicz artery: comparison of the detection rate of intravenous injection CT angiography using a 64-slice MDCT versus intra-arterial and intravenous injection CT angiography using a 16-slice MDCT.

    PubMed

    Nishii, Tatsuya; Kono, Atsushi K; Negi, Noriyuki; Hashimura, Hiromi; Uotani, Kensuke; Okita, Yutaka; Sugimura, Kazuro

    2013-12-01

    Identification of the Adamkiewicz artery (AKA) using CT angiography (CTA) is crucial in patients with thoracic aortic aneurysm (TAA) or aortic dissection (AD). The purpose of this study was to compare the AKA detection rate of intravenous injection with a 64-slice MDCT (IV64) versus a 16-slice MDCT (IV16) as well as by CTA using intra-arterial injection with a 16-slice MDCT (IA16). A retrospective review of 160 consecutive patients who underwent CTA was performed. There were 108 TAA and 52 AD cases, 105 of whom were examined with IV64, 15 with IV16, and 40 with IA16. The AKA detectability for each imaging method was assessed, and the factors influencing the detectability were analyzed by multivariate analysis. The detection rates for IV64, IV16, and IA16 were 85.7, 60.0, and 80.0 %, respectively, with IV64 being more sensitive than IV16 (P = 0.025). The detection rate for AD patients was 66.7 % with IV64, which was similar to IV16 (57.1 %) and IA16 (66.8 %). On the other hand, the detection rate for TAA patients was 93.3 % with IV64, which was higher than IV16 (62.5 %, P = 0.021) and similar to IA16 (88.0 %). Multivariate analysis demonstrated the independent factors for AKA detectability were TAA versus AD (P = 0.005, Odds ratio = 3.98) and IV64 versus IV16 (P = 0.037, Odds ratio = 4.03). The detection rate was higher for IV64 than for IV16, especially for TAA patients, while the rate was similar between IV64 and invasive IA16. A 64-slice MDCT thus provides a less invasive visualization of the AKA.

  2. Clinical arthrography

    SciTech Connect

    Arndt, R.; Horns, J.W.; Gold, R.H.; Blaschke, D.D.

    1985-01-01

    This book deals with the method and interpretation of arthrography of the shoulder, knee, ankle, elbow, hip, wrist, and metacarpophalangeal, interphalangeal, and temporomandibular joints. The emphasis is on orthopaedic disorders, usually of traumatic origin, which is in keeping with the application of arthrography in clinical practice. Other conditions, such as inflammatory and degenerative diseases, congenital disorders and, in the case of the hip, arthrography of reconstructive joint surgery, are included. Each chapter is devoted to one joint and provides a comprehensive discussion on the method of arthrography, including single and double contrast techniques where applicable, normal radiographic anatomy, and finally, the interpretation of the normal and the abnormal arthrogram.

  3. Cardiac Computed Tomography (Multidetector CT, or MDCT)

    MedlinePlus

    ... High Blood Pressure Tools & Resources Stroke More Cardiac Computed Tomography (Multidetector CT, or MDCT) Updated:Sep 3,2015 ... facts MDCT is a very fast type of computed tomography (CT) scan. MDCT creates pictures of the healthy ...

  4. Arthrography

    MedlinePlus

    ... through the body, recording an image on photographic film or a special detector. Different parts of the ... recently, x-ray images were maintained on large film sheets (much like a large photographic negative). Today, ...

  5. Usefulness of 4-, 8-, and 16-slice computed tomography for detection of graft occlusion or patency after coronary artery bypass grafting.

    PubMed

    Stein, Paul D; Beemath, Afzal; Skaf, Elias; Kayali, Fadi; Janjua, Muhammad; Alesh, Issa; Olson, Ronald E

    2005-12-15

    The sensitivity and specificity of computed tomographic angiography for the evaluation of coronary artery bypass grafts (CABGs) was reviewed. A search of published studies in all languages was performed, incorporating electronic and manual components. A total of 985 patients with 2,200 CABGs participated in investigations with single-detector computed tomography (CT), 441 patients (1,246 CABGs) with 4-slice CT, none with 8-slice CT, and 144 patients (416 grafts) with 16-slice CT. Pooled data showed a sensitivity for the detection of complete occlusion with single-slice CT of 81% (402 of 494 patients), with 4-slice CT of 93% (293 of 315 patients), and with 16-slice CT of 99% (75 of 76 patients). The specificity, based on pooled data, using single-slice CT was 89% (1,507 of 1,697 patients), with 4-slice CT was 96% (878 of 915 patients), and with 16-slice CT was 98% (301 of 306 patients). The detection of complete occlusion and the detection of patency in saphenous vein bypass grafts and arterial bypass grafts were similar with multislice CT. Limited data were available on the detection of significant stenosis, exclusive of complete occlusion. With 4-slice CT, the sensitivity was 74% (23 of 31 patients) and was 88% (21 of 24 patients) with 16-slice CT. In conclusion, single-detector CT was able to detect graft patency, but it was not sensitive for graft occlusion. The data suggest that 4- and 16-slice CT can be used for the detection of complete graft occlusion or graft patency of CABGs. Significant stenosis was better assessed with 16-slice CT than with 4-slice CT. PMID:16360355

  6. MDCT and MR imaging of the jejunum.

    PubMed

    El Fattach, H; Dohan, A; Guerrache, Y; Dautry, R; Eveno, C; Boudiaf, M; Hoeffel, C; Soyer, P

    2015-03-01

    Recent refinements in cross-sectional imaging have dramatically modified the investigation of the jejunum. Improvements in multidetector row computed tomography (MDCT) and magnetic resonance (MR) imaging technology have made detection and characterization of jejunal abnormalities easier. Current options include MDCT and MR imaging using either enterography or enteroclysis. The goal of this pictorial review is to outline the current imaging techniques that are used to investigate the jejunum and illustrate the most common conditions that affect this small bowel segment with a specific focus on MDCT and MR imaging using enterography or enteroclysis. MR imaging used in conjunction with optimal jejunal distension appears as the modality of choice for the diagnosis of a wide range of jejunal abnormalities. MDCT remains the first line imaging modalities because of an acute presentation in a substantial number of patients. PMID:25482665

  7. Magnetic Resonance Arthrography of the Wrist and Elbow.

    PubMed

    LiMarzi, Gary M; O'Dell, M Cody; Scherer, Kurt; Pettis, Christopher; Wasyliw, Christopher W; Bancroft, Laura W

    2015-08-01

    Magnetic resonance (MR) arthrography of the wrist and elbow is useful for detecting a variety of intra-articular pathologies. MR dictations should address whether intrinsic ligament tears of the wrist are partial-thickness or full-thickness, and involve the dorsal, membranous, and/or volar components of the ligaments. With regard to elbow soft tissue pathology, partial-thickness tears of the anterior band of the ulnar collateral ligament in overhead-throwing athletes are well evaluated with MR arthrography. MR arthrography also is helpful in staging osteochondritis dissecans of the capitellum, caused by repetitive valgus impaction injury in adolescent or young adult baseball pitchers.

  8. A Severe Case of Arthrographis kalrae Keratomycosis

    PubMed Central

    Francis, Alex Lourdes; Yusof, Yushaniza; Khaithir, Tzar Mohd Nizam

    2013-01-01

    A 52-year-old man with diabetes developed a unilateral central corneal ulcer after accidental foreign body inoculation. He complained of pain and loss of visual acuity in the injured eye, which displayed redness and edema and eventually discharged pus. A corneal scraping from the left eye orbit revealed fungal elements, and cultures of the material grew a fungus. The isolate was identified as Arthrographis kalrae based on gross and microscopic morphologies. The patient received amphotericin B intravenously and itraconazole orally. The wound healed following surgical intervention, but the patient lost the use of his left eye. PMID:24377053

  9. Arthrography and arthrotomy of the knee in sports injuries.

    PubMed Central

    Kulthanan, T; Noiklang, P

    1993-01-01

    A total of 266 patients with injuries to the knee sustained during sports activities were managed by arthroscopy and/or arthrotomy. All of them received systemic examination and a standard battery of knee stability tests. Fifty-three were examined by arthrography and all underwent arthrotomy for surgical correction of the lesion diagnosed by both clinical examination and arthrography. Our study showed that clinical examination could give an accurate clinical diagnosis in 88.35% of cases and arthrography in 76.89%. No complication from arthrography was found. Injury occurred most commonly between 21 and 30 years of age and was more common to the right knee than the left. The sport in which most injuries occurred was football. PMID:8358590

  10. Multidetector spiral CT arthrography of the shoulder. Clinical applications and limits, with MR arthrography and arthroscopic correlations.

    PubMed

    Lecouvet, Frédéric E; Simoni, Paolo; Koutaïssoff, Sophie; Vande Berg, Bruno C; Malghem, Jacques; Dubuc, Jean-Emile

    2008-10-01

    Although MR imaging and MR arthrography are the first choice modalities for shoulder imaging, CT arthrography (CTA) may be used successfully to address many clinical questions. The advent of submillimeter multiple detector CT technology and subsequent excellent three-plane resolution has considerably increased the quality of CTA examinations and has propelled this technique to the forefront in a growing number of indications. The combined use of iodinated contrast material for fluoroscopic confirmation of the articular position of the needle before injection of gadolinium chelates for MR arthrography offers the unique opportunity to compare CTA and MRA findings in carefully selected cases. This paper illustrates capabilities and limits of CTA for the study of rotator cuff tears, shoulder instability, cartilage lesions, anatomical variants and abnormalities of the glenoid labrum, with correlations to MR arthrography and surgical findings.

  11. MDCT evaluation of acute aortic syndrome (AAS).

    PubMed

    Valente, Tullio; Rossi, Giovanni; Lassandro, Francesco; Rea, Gaetano; Marino, Maurizio; Muto, Maurizio; Molino, Antonio; Scaglione, Mariano

    2016-01-01

    Non-traumatic acute thoracic aortic syndromes (AAS) describe a spectrum of life-threatening aortic pathologies with significant implications on diagnosis, therapy and management. There is a common pathway for the various manifestations of AAS that eventually leads to a breakdown of the aortic intima and media. Improvements in biology and health policy and diffusion of technology into the community resulted in an associated decrease in mortality and morbidity related to aortic therapeutic interventions. Hybrid procedures, branched and fenestrated endografts, and percutaneous aortic valves have emerged as potent and viable alternatives to traditional surgeries. In this context, current state-of-the art multidetector CT (MDCT) is actually the gold standard in the emergency setting because of its intrinsic diagnostic value. Management of acute aortic disease has changed with the increasing realization that endovascular therapies may offer distinct advantages in these situations. This article provides a summary of AAS, focusing especially on the MDCT technique, typical and atypical findings and common pitfalls of AAS, as well as recent concepts regarding the subtypes of AAS, consisting of aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer and unstable aortic aneurysm or contained aortic rupture. MDCT findings will be related to pathophysiology, timing and management options to achieve a definite and timely diagnostic and therapeutic definition. In the present article, we review the aetiology, pathophysiology, clinical presentation, outcomes and therapeutic approaches to acute aortic syndromes. PMID:27033344

  12. Dose reduction in paediatric MDCT: general principles.

    PubMed

    Paterson, A; Frush, D P

    2007-06-01

    The number of multi-detector array computed tomography (MDCT) examinations performed per annum continues to increase in both the adult and paediatric populations. Estimates from 2003 suggested that CT contributed 17% of a radiology department's workload, yet was responsible for up to 75% of the collective population dose from medical radiation. The effective doses for some CT examinations today overlap with those argued to have an increased risk of cancer. This is especially pertinent for paediatric CT, as children are more radiosensitive than adults (and girls more radiosensitive than boys). In addition, children have a longer life ahead of them, in which radiation induced cancers may become manifest. Radiologists must be aware of these facts and practise the ALARA (as low as is reasonably achievable) principle, when it comes to deciding CT protocols and parameters. PMID:17467387

  13. Giant colonic diverticulum: radiographic and MDCT characteristics.

    PubMed

    Zeina, Abdel-Rauf; Mahamid, Ahmad; Nachtigal, Alicia; Ashkenazi, Itamar; Shapira-Rootman, Mika

    2015-12-01

    Giant colonic diverticulum (GCD), defined as a diverticulum larger than 4 cm, is a rare entity that is generally a manifestation of colonic diverticular disease. Because of its rarity and its variable and non-specific presentation, the diagnosis of GCD depends mainly on imaging findings. Knowledge of the spectrum of radiographic and CT features of the GCD is important in making the correct diagnosis and potentially preventing complications. This review focuses on imaging findings characteristic of GCD as well as its complications and radiographic mimics. Teaching points • Giant colonic diverticulum is a rare complication of diverticulosis.• The most common symptom is abdominal pain presenting in approximately 70 % of patients.• Diagnosis is based on imaging findings with plain abdominal radiographs and MDCT.• Treatment consists of en bloc resection of the diverticulum and affected adjacent colon.

  14. Temporal resolution improvement using PICCS in MDCT cardiac imaging.

    PubMed

    Chen, Guang-Hong; Tang, Jie; Hsieh, Jiang

    2009-06-01

    The current paradigm for temporal resolution improvement is to add more source-detector units and/or increase the gantry rotation speed. The purpose of this article is to present an innovative alternative method to potentially improve temporal resolution by approximately a factor of 2 for all MDCT scanners without requiring hardware modification. The central enabling technology is a most recently developed image reconstruction method: Prior image constrained compressed sensing (PICCS). Using the method, cardiac CT images can be accurately reconstructed using the projection data acquired in an angular range of about 120 degrees, which is roughly 50% of the standard short-scan angular range (approximately 240 degrees for an MDCT scanner). As a result, the temporal resolution of MDCT cardiac imaging can be universally improved by approximately a factor of 2. In order to validate the proposed method, two in vivo animal experiments were conducted using a state-of-the-art 64-slice CT scanner (GE Healthcare, Waukesha, WI) at different gantry rotation times and different heart rates. One animal was scanned at heart rate of 83 beats per minute (bpm) using 400 ms gantry rotation time and the second animal was scanned at 94 bpm using 350 ms gantry rotation time, respectively. Cardiac coronary CT imaging can be successfully performed at high heart rates using a single-source MDCT scanner and projection data from a single heart beat with gantry rotation times of 400 and 350 ms. Using the proposed PICCS method, the temporal resolution of cardiac CT imaging can be effectively improved by approximately a factor of 2 without modifying any scanner hardware. This potentially provides a new method for single-source MDCT scanners to achieve reliable coronary CT imaging for patients at higher heart rates than the current heart rate limit of 70 bpm without using the well-known multisegment FBP reconstruction algorithm. This method also enables dual-source MDCT scanner to achieve higher

  15. MDCT of the hand and wrist: beyond trauma.

    PubMed

    Ahlawat, Shivani; Corl, Frank M; Fishman, Elliot K; Fayad, Laura M

    2015-06-01

    High-resolution multidetector computed tomography (MDCT) has played a pivotal role in assessing patients following trauma; however, recent advancements in technology including dual-energy CT, as well as multiplanar and three-dimensional (3D) capabilities, are expanding the potential clinical applications of CT to include nontraumatic pathologies. This article will review optimal technical parameters for the creation of MDCT and 3DCT images and illustrate the imaging capabilities of 3DCT imaging for demonstrating nontraumatic hand and wrist pathology. PMID:25301374

  16. [Value of contrast arthrography in the diagnosis of hemophilic arthropathy].

    PubMed

    Andreev, Iu N; Vishnevskaia, E S; Kagan, I E

    1990-10-01

    X-ray semiotics of changes in the roentgen-negative components of the knee joint at different stages of hemophilic arthropathy has been described basing on the study of 46 contrast arthrography ++ of the joint, and their correlation with the results of macroscopic and histological investigations of the tissues removed during surgery. Identification of the character of the damage in the soft-tissue and cartilage components of the joint is particularly important at the early stages of arthropathy, as it enables determining the optimum therapeutic tactics when the data of routine roentgenography give insufficient information, and changes in the bones are limited and, as a rule, reversible.

  17. Direct magnetic resonance arthrography of the canine shoulder.

    PubMed

    Schaefer, Susan L; Baumel, Cheryl A; Gerbig, Jamie R; Forrest, Lisa J

    2010-01-01

    Our goal was to evaluate the ability of three magnetic resonance arthrography (MRA) techniques to improve visualization of soft tissue stabilizing components of the canine shoulder. The optimum concentration of gadolinium (gadodiamide) for MRA was determined by imaging seven individual shoulders with one of seven dilutions of 0.5 mol/l gadodiamide in saline; (1:100, 1:400, 1:800, 1:1000, 1:1200, 1:1400, and 1:1600). For this, sagittal and dorsal T1-weighted fat saturation (T1WFS) images were used. The 1:1200 dilution of gadolinium was determined to be the optimum concentration as it provided adequate contrast to distinguish supporting joint structures without obscuring the edges of those structures. Sagittal, dorsal, and transverse MRA images were then acquired in nine cadaver shoulders using T1WFS with gadolinium, proton density fat saturation (PDFS) with gadolinium, and PDFS with saline. Descriptive comparisons were made among techniques. When gadolinium was compared with saline as a contrast medium, gadolinium provided greater contrast against underlying soft tissues, thereby enhancing tendon and ligament conspicuity. When T1WFS and PDFS gadolinium sequences were compared, minor differences were noted. The interface between tissue and fluid was sharper and more distinct in PDFS images. MRI arthrography has promise as a tool for the diagnosis of canine soft tissue shoulder injury. MRA may be most useful when trauma to the biceps tendon, lateral glenohumeral ligament, or medial glenohumeral ligament is suspected.

  18. Epinephrine-enhanced computed tomographic arthrography of the canine shoulder.

    PubMed

    De Rycke, Lieve; van Bree, Henri; Van Caelenberg, Annemie; Polis, Ingeborgh; Duchateau, Luc; Gielen, Ingrid

    2015-10-01

    The aim of this study was to investigate the effect of epinephrine-enhanced computed tomographic arthrography (CTA) on the image sharpness of the lateral and medial glenohumeral ligaments (LGHL and MGHL, respectively), biceps tendon (BT) and joint cartilage (JC) in the canine shoulder. The shoulders of eight normal dogs were examined using a 4-slice helical CT scanner. The right shoulders were injected with Iohexol and the left shoulders with a mixture of Iohexol and epinephrine. CTA images were obtained after 1, 3, 5, 9, 13, 20 and 30 min and the image sharpness of the intra-articular structures in both shoulders was graded for visibility. The attenuation values were measured to examine the persistence of contrast appearance. Admixture of epinephrine and Iohexol significantly improved the image sharpness of the LGHL and the BT, especially on delayed CTA images. The use of epinephrine did not negatively affect post-CTA recovery. PMID:26412512

  19. Bypass graft imaging and coronary anomalies in MDCT.

    PubMed

    Fernandez, Gabriel C

    2005-02-01

    Coronary artery bypass graft (CABG) is used to restore the blood flow in an ischemic area of myocardium using conduits bypassing a diseased coronary artery. Until now, conventional angiography has been the recognized technique to study patients with bypass grafts. Nowadays, non-invasive methods such as multi-detector CT (MDCT) emerge as reliable imaging methods in the study of CABG. Thus, radiologists play an important role in this field, not only to define if the bypass graft is occluded or stenosed but also to report further information such as CABG technique performed, type of conduit used or pre-operative findings. This paper analyzes the most practical information that the radiologist must know in a study of CABG. Another theme which will be briefly described is the use of MDCT in coronary anomalies studies, with particular emphasis on the course of the abnormal vessel and its relation to great vessels. PMID:15801059

  20. Bursae and abscess cavities communicating with the hip: diagnosis using arthrography and CT

    SciTech Connect

    Steinbach, L.S.; Schneider, R.; Goldman, A.B.; Kazam, E.; Ranawat, C.S.; Ghelman, B.

    1985-08-01

    Bursae or abscess cavities communicating with the hip joint were demonstrated by hip arthrography or by computed tomography (CT) in 40 cases. The bursae or abscess cavities were associated with underlying abnormalities in the hip, including painful hip prostheses, infection, and inflammatory or degenerative arthritis. Symptoms may be produced directly as a result of infection or indirectly as a result of inflammation or pressure on adjacent structures. Hip arthrography can confirm a diagnosis of bursae and abscess cavities communicating with the hip joint in patients with hip pain or soft-tissue masses around the groin. Differentiation of enlarged bursae from other abnormalities is important to avoid unnecessary or incorrect surgery.

  1. MDCT of acute colitis in adults: an update in current imaging features.

    PubMed

    Barral, M; Boudiaf, M; Dohan, A; Hoeffel, C; Camus, M; Pautrat, K; Fishman, E K; Cohen, S; Soyer, P

    2015-02-01

    Acute colitis is often diagnosed on multidetector row computed tomography (MDCT) because patients with this condition present with abdominal pain and a variety of nonspecific symptoms. Acute colitis has multiple causes with varying degrees of severity. Analysis of the extent of colonic involvement, presence of specific MDCT imaging features and associated signs should help radiologist narrow the diagnosis. Integrating the results of clinical examination and biological tests is mandatory, and in case of ambiguous or nonspecific MDCT findings, endoscopy and colon biopsy should always be considered for a definite diagnosis. The purpose of this review is to discuss and illustrate MDCT features that are helpful for characterizing acute colitis in adults and to provide an update in current MDCT features. PMID:24835625

  2. MDCT of acute colitis in adults: an update in current imaging features.

    PubMed

    Barral, M; Boudiaf, M; Dohan, A; Hoeffel, C; Camus, M; Pautrat, K; Fishman, E K; Cohen, S; Soyer, P

    2015-02-01

    Acute colitis is often diagnosed on multidetector row computed tomography (MDCT) because patients with this condition present with abdominal pain and a variety of nonspecific symptoms. Acute colitis has multiple causes with varying degrees of severity. Analysis of the extent of colonic involvement, presence of specific MDCT imaging features and associated signs should help radiologist narrow the diagnosis. Integrating the results of clinical examination and biological tests is mandatory, and in case of ambiguous or nonspecific MDCT findings, endoscopy and colon biopsy should always be considered for a definite diagnosis. The purpose of this review is to discuss and illustrate MDCT features that are helpful for characterizing acute colitis in adults and to provide an update in current MDCT features.

  3. Coronary lesion complexity assessed by SYNTAX score in 256-slice dual-source MDCT angiography

    PubMed Central

    Yüceler, Zeyneb; Kantarcı, Mecit; Tanboğa, İbrahim Halil; Sade, Recep; Kızrak, Yeşim; Pirimoğlu, Berhan; Bayraktutan, Ümmügülsüm; Oğul, Hayri; Aksakal, Enbiya

    2016-01-01

    PURPOSE The SYNTAX Score (SS) has an important role in grading the complexity of coronary artery disease (CAD) in patients undergoing revascularization. Noninvasive determination of SS prior to invasive coronary angiography (ICA) might optimize patient management. We aimed to evaluate the agreement between ICA and multidetector computed tomography (MDCT) while testing the diagnostic effectiveness of SS-MDCT. METHODS Our study included 108 consecutive patients who underwent both MDCT angiography with a 256-slice dual-source MDCT system and ICA within 14±3 days. SS was calculated for both ICA and MDCT coronary angiography. Spearman’s rank correlation coefficient was used to evaluate the association of SS-MDCT with SS-ICA, and Bland-Altman analysis was performed. RESULTS The degree of agreement between SS-ICA and SS-MDCT was moderate. The mean SS-MDCT was 14.5, whereas the mean SS-ICA was 15.9. After dividing SS into three groups (high [≥33], intermediate [23–32], and low [≤22] subgroups), agreement analysis was repeated. There was a significant correlation between SS-MDCT and SS-ICA in the low SS group (r=0.63, P = 0.043) but no significant correlation in the high SS group (r=0.036, P = 0.677). The inter-test agreement analysis showed at least moderate agreement, whereas thrombotic lesions and the type of bifurcation lesion showed fair agreement. CONCLUSION The calculation of SS-MDCT by adapting SS-ICA parameters achieved nearly the same degree of precision as SS-ICA and was better than SS-ICA, especially in the low SS group. PMID:27328718

  4. In vivo diagnostics of human knee cartilage lesions using delayed CBCT arthrography.

    PubMed

    Kokkonen, Harri T; Suomalainen, Juha-Sampo; Joukainen, Antti; Kröger, Heikki; Sirola, Joonas; Jurvelin, Jukka S; Salo, Jari; Töyräs, Juha

    2014-03-01

    The aim of this study was to investigate the feasibility of delayed cone beam (CBCT) arthrography for clinical diagnostics of knee cartilage lesions. Knee joints with cartilage lesions were imaged using native radiography, MRI, and delayed CBCT arthrography techniques in vivo. The joints were imaged three times with CBCT, just before, immediately after (arthrography) and 45 min after the intra-articular injection of contrast agent. The arthrographic images enabled sensitive detection of the cartilage lesions. Use of arthrographic and delayed images together with their subtraction image enabled also detection of cartilage with inferior integrity. The contrast agent partition in intact cartilage (ICRS grade 0) was lower (p < 0.05) than that of cartilage surrounding the ICRS grade I-IV lesions. Delayed CBCT arthrography provides a novel method for diagnostics of cartilage lesions. Potentially, it can also be used in diagnostics of cartilage degeneration. Due to shorter imaging times, higher resolution, and lower costs of CT over MRI, this technique could provide an alternative for diagnostics of knee pathologies. However, for comprehensive evaluation of the clinical potential of the technique a further clinical study with a large pool of patients having a wide range of cartilage pathologies needs to be conducted.

  5. Mixed-radix Algorithm for the Computation of Forward and Inverse MDCT

    PubMed Central

    Wu, Jiasong; Shu, Huazhong; Senhadji, Lotfi; Luo, Limin

    2008-01-01

    The modified discrete cosine transform (MDCT) and inverse MDCT (IMDCT) are two of the most computational intensive operations in MPEG audio coding standards. A new mixed-radix algorithm for efficient computing the MDCT/IMDCT is presented. The proposed mixed-radix MDCT algorithm is composed of two recursive algorithms. The first algorithm, called the radix-2 decimation in frequency (DIF) algorithm, is obtained by decomposing an N-point MDCT into two MDCTs with the length N/2. The second algorithm, called the radix-3 decimation in time (DIT) algorithm, is obtained by decomposing an N-point MDCT into three MDCTs with the length N/3. Since the proposed MDCT algorithm is also expressed in the form of a simple sparse matrix factorization, the corresponding IMDCT algorithm can be easily derived by simply transposing the matrix factorization. Comparison of the proposed algorithm with some existing ones shows that our proposed algorithm is more suitable for parallel implementation and especially suitable for the layer III of MPEG-1 and MPEG-2 audio encoding and decoding. Moreover, the proposed algorithm can be easily extended to the multidimensional case by using the vector-radix method. PMID:21258639

  6. Detection of intraarticular loose osteochondral fragments by double-contrast wrist arthrography. A case report of a basketball injury.

    PubMed

    Tehranzadeh, J; Labosky, D A

    1984-01-01

    Gravity was used in a case of double-contrast wrist arthrography to demonstrate the intraarticular loose nature of osteochondral fracture fragments. These calcified loose bodies were successfully removed surgically.

  7. Perinephric abscess caused by ruptured retrocecal appendix: MDCT demonstration

    PubMed Central

    Wani, Nisar Ahmad; Farooq, Mir; Gojwari, Tariq; Kosar, Tasleem

    2010-01-01

    Acute appendicitis may occasionally become extraordinarily complicated and life threatening yet difficult to diagnose. One such presentation is described in a 60-year-old man who was brought to the hospital due to right lumbar pain and fever for the last 15 days. Ultrasonography showed a right perinephric gas and fluid collection. Abdominal computed tomography with multidetector-row CT (MDCT) revealed gas-containing abscess in the right retroperitoneal region involving the perinephric space, extending from the lower pole of the right kidney up to the bare area of the liver. Inflamed retrocecal appendix was seen on thick multiplanar reformat images with its tip at the lower extent of the abscess. Laparotomy and retroperitoneal exploration were performed immediately and a large volume of foul smelling pus was drained. A ruptured retrocecal appendix was confirmed as the cause of the abscess. PMID:20842255

  8. Polyarteritis nodosa: MDCT as a 'One-Stop Shop' Modality for Whole-Body Arterial Evaluation

    SciTech Connect

    Tsai, W.-L.; Tsai, I-C.; Lee Tain; Hsieh, C.-W.

    2008-07-15

    Polyarteritis nodosa is a rare disease, which is characterized by aneurysm formation and occlusion in the arteries of multiple systems. Due to its extensive involvement, whole-body evaluation is necessary for diagnosis and treatment monitoring. We report a case of polyarteritis nodosa using multidetector-row computed tomography (MDCT) as a 'one-stop shop' modality for whole-body arterial evaluation. With precise protocol design, MDCT can be used as a reliable noninvasive modality providing comprehensive whole-body arterial evaluation.

  9. Three-dimensional MDCT angiography for the assessment of arteriovenous grafts and fistulas in hemodialysis access.

    PubMed

    Ahmed, S; Raman, S P; Fishman, E K

    2016-03-01

    Arteriovenous grafts and fistulas are placed for long-term hemodialysis access, and their associated complications can lead to considerable morbidity. Multi-detector computed tomography (MDCT) images provide accurate delineation of hemodialysis access anatomy and show potential complications. This review makes the reader more familiar with vascular access anatomy and configurations, describes the appearance of access complications encountered on MDCT, and discusses endovascular and surgical treatment options for complications, which should aid in post-treatment evaluation. PMID:26868603

  10. Defining vascular signatures of benign hepatic masses: role of MDCT with 3D rendering.

    PubMed

    Ahmed, Sameer; Johnson, Pamela T; Fishman, Elliot K

    2013-08-01

    Multidetector CT (MDCT) provides new opportunities for hepatic tumor characterization. By coupling high-resolution isotropic datasets with advanced post-processing tools, maps of tumor vascularity can be generated to elucidate characteristic findings. This two-part review describes a range of benign and malignant liver masses, with emphasis on IV contrast-enhanced MDCT features and vascular signatures that can be identified on 3D vascular mapping.

  11. A Prototype Body-Mounted MRI-Compatible Robot for Needle Guidance in Shoulder Arthrography.

    PubMed

    Monfaredi, R; Seifabadi, R; Iordachita, I; Sze, R; Safdar, N M; Sharma, K; Fricke, S; Krieger, A; Cleary, K

    2014-08-01

    A novel compact and lightweight patient-mounted MRI-compatible robot has been designed for MRI image-guided interventions. This robot is intended to enable MRI-guided needle placement as done in shoulder arthrography. The robot could make needle placement more accurate and simplify the current workflow by converting the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure (streamlined workflow all in MRI suite). The robot has 4 degrees of freedom (DOF), two for orientation of the needle and two for needle positioning. The mechanical design was based on several criteria including rigidity, MRI compatibility, compact design, sterilizability, and adjustability. The proposed workflow is discussed and initial MRI compatibility experiments are presented. The results show that artifacts in the region of interest are minimal and that MRI images of the shoulder were not adversely affected by placing the robot on a human volunteer. PMID:25473653

  12. A Prototype Body-Mounted MRI-Compatible Robot for Needle Guidance in Shoulder Arthrography

    PubMed Central

    Monfaredi, R.; Seifabadi, R.; Iordachita, I.; Sze, R.; Safdar, N. M.; Sharma, K.; Fricke, S.; Krieger, A.; Cleary, K.

    2014-01-01

    A novel compact and lightweight patient-mounted MRI-compatible robot has been designed for MRI image-guided interventions. This robot is intended to enable MRI-guided needle placement as done in shoulder arthrography. The robot could make needle placement more accurate and simplify the current workflow by converting the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure (streamlined workflow all in MRI suite). The robot has 4 degrees of freedom (DOF), two for orientation of the needle and two for needle positioning. The mechanical design was based on several criteria including rigidity, MRI compatibility, compact design, sterilizability, and adjustability. The proposed workflow is discussed and initial MRI compatibility experiments are presented. The results show that artifacts in the region of interest are minimal and that MRI images of the shoulder were not adversely affected by placing the robot on a human volunteer. PMID:25473653

  13. Quantification of arterial plaque and lumen density with MDCT

    SciTech Connect

    Paul, Narinder S.; Blobel, Joerg; Kashani, Hany; Rice, Murray; Ursani, Ali

    2010-08-15

    Purpose: This study aimed to derive a mathematical correction function in order to normalize the CT number measurements for small volume arterial plaque and small vessel mimicking objects, imaged with multidetector CT (MDCT). Methods: A commercially available calcium plaque phantom (QRM GmbH, Moehrendorf, Germany) and a custom built cardiovascular phantom were scanned with 320 and 64 MDCT scanners. The calcium hydroxyapatite plaque phantom contained objects 0.5-5.0 mm in diameter with known CT attenuation nominal values ranging 50-800 HU. The cardiovascular phantom contained vessel mimicking objects 1.0-5.0 mm in diameter with different contrast media. Both phantoms were scanned using clinical protocols for CT angiography and images were reconstructed with different filter kernels. The measured CT number (HU) and diameter of each object were analyzed on three clinical postprocessing workstations. From the resultant data, a mathematical formula was derived based on absorption function exp(-{mu}{sup *}d) to demonstrate the relation between measured CT numbers and object diameters. Results: The percentage reduction in measured CT number (HU) for the group of selected filter kernels, apparent during CT angiography, is dependent only on the object size (plaque or vessel diameter). The derived formula of the form 1-c{sup *}exp(-a{sup *}d{sup b}) showed reduction in CT number for objects between 0.5 and 5 mm in diameter, with asymptote reaching background noise for small objects with diameters nearing the CT in-plane resolution (0.35 mm). No reduction was observed for the objects with diameters equal or larger than 5 mm. Conclusions: A clear mathematical relationship exists between object diameter and reduction in measured CT number in HU. This function is independent of exposure parameters and inherent attenuation properties of the objects studied. Future developments include the incorporation of this mathematical model function into quantification software in order to

  14. Three-dimensional reconstruction of upper airways from MDCT

    NASA Astrophysics Data System (ADS)

    Perchet, Diane; Fetita, Catalin; Preteux, Francoise

    2005-03-01

    Under the framework of clinical respiratory investigation, providing accurate modalities for morpho-functional analysis is essential for diagnosis improvement, surgical planning and follow-up. This paper focuses on the upper airways investigation and develops an automated approach for 3D mesh reconstruction from MDCT acquisitions. In order to overcome the difficulties related to the complex morphology of the upper airways and to the image gray level heterogeneity of the airway lumens and thin bony septa, the proposed 3D reconstruction methodology combines 2D segmentation and 3D surface regularization approaches. The segmentation algorithm relies on mathematical morphology theory and provides airway lumen robust discrimination from the surrounding tissues, while preserving the connectivity relationship between the different anatomical structures. The 3D regularization step uses an energy-based modeling in order to achieve a smooth and well-fitted 3D surface of the upper airways. An accurate 3D mesh representation of the reconstructed airways makes it possible to develop specific clinical applications such as virtual endoscopy, surgical planning and computer assisted intervention. In addition, building up patient-specific 3D models of upper airways is highly valuable for the study and design of inhaled medication delivery via computational fluid dynamics (CFD) simulations.

  15. CT angiography of neonates and infants: comparison of radiation dose and image quality of target mode prospectively ECG-gated 320-MDCT and ungated helical 64-MDCT.

    PubMed

    Jadhav, Siddharth P; Golriz, Farahnaz; Atweh, Lamya A; Zhang, Wei; Krishnamurthy, Rajesh

    2015-02-01

    OBJECTIVE. The purpose of this study was to evaluate the radiation dose and image quality of target mode prospectively ECG-gated volumetric CT angiography (CTA) performed with a 320-MDCT scanner compared with the radiation dose and image quality of ungated helical CTA performed with a 64-MDCT scanner. MATERIALS AND METHODS. An experience with CTA for cardiovascular indications in neonates and infants 0-6 months old was retrospectively assessed. Radiation doses and quantitative and qualitative image quality scores of 28 CTA examinations performed with a 320-MDCT scanner and volumetric target mode prospective ECG gating plus iterative reconstruction (target mode) were compared with the doses and scores of 28 CTA examinations performed with a 64-MDCT scanner and ungated helical scanning plus filtered back projection reconstruction (ungated mode). All target mode studies were performed during free breathing. Seven ungated CTA examinations (25%) were performed with general endotracheal anesthesia. The findings of 17 preoperative CTA examinations performed in target mode were also compared with surgical reports for evaluation of diagnostic accuracy. RESULTS. All studies performed with target mode technique were diagnostic for the main clinical indication. Effective doses were significantly lower in the target mode group (0.51 ± 0.19 mSv) compared with the ungated mode group (4.8 ± 1.4 mSv) (p < 0.0001). Quantitative analysis revealed no statistically significant difference between the two groups with respect to signal-to-noise ratio (of pulmonary artery and aorta) and contrast-to-noise ratio. Subjective image quality was significantly better with target mode than with ungated mode (p < 0.0001). CONCLUSION. Target mode prospectively ECG-gated volumetric scanning with iterative reconstruction performed with a 320-MDCT scanner has several benefits in cardiovascular imaging of neonates and infants, including low radiation dose, improved image quality, high diagnostic

  16. Robust extraction of the aorta and pulmonary artery from 3D MDCT image data

    NASA Astrophysics Data System (ADS)

    Taeprasartsit, Pinyo; Higgins, William E.

    2010-03-01

    Accurate definition of the aorta and pulmonary artery from three-dimensional (3D) multi-detector CT (MDCT) images is important for pulmonary applications. This work presents robust methods for defining the aorta and pulmonary artery in the central chest. The methods work on both contrast enhanced and no-contrast 3D MDCT image data. The automatic methods use a common approach employing model fitting and selection and adaptive refinement. During the occasional event that more precise vascular extraction is desired or the method fails, we also have an alternate semi-automatic fail-safe method. The semi-automatic method extracts the vasculature by extending the medial axes into a user-guided direction. A ground-truth study over a series of 40 human 3D MDCT images demonstrates the efficacy, accuracy, robustness, and efficiency of the methods.

  17. Feasibility of Free-breathing CCTA using 256-MDCT.

    PubMed

    Liu, Zhuo; Sun, Ye; Zhang, Zhuolu; Chen, Lei; Hong, Nan

    2016-07-01

    Usually, coronary computed tomography angiography (CCTA) is performed during breath-holding to reduce artifact caused by respiration. The objective of this study was to evaluate the feasibility of free-breathing CCTA compared to breath-holding using CT scanner with wide detector. To evaluate the feasibility of CCTA during free-breathing using a 256-MDCT. In 80 patients who underwent CCTA, 40 were performed during breath-holding (group A), and the remaining 40 during free-breathing (group B). The quality scores for coronary arteries were analyzed and defined as: 3 (excellent), 2 (good), and 1 (poor). The image noise, signal-to-noise ratio and effective radiation dose as well as the heart rate variation were compared. The noise, signal-to-noise ratio, and effective radiation dose were not significantly different between the 2 groups. The mean heart rate variation between planning and scanning for group A was 7 ± 7.6 bpm, and larger than 3 ± 2.6 bpm for group B (P = 0.012). Quality scores of the free-breathing group were better than those of the breath-holding group (group A: 2.55 ± 0.64, group B: 2.85 ± 0.36, P = 0.018). Free-breathing CCTA is feasible on wide detector CT scanner to provide acceptable image quality with reduced heart rate variation and better images for certain patients. PMID:27399104

  18. US and MDCT findings in a caudal blind ending bifid ureter with calculi

    PubMed Central

    Ustuner, Evren; Atman, Ebru Dusunceli; Yagci, Cemil; Tokatli, Zafer Nida; Uzun, Caglar

    2011-01-01

    Herein we present a rare ureteric duplication anomaly; blind ending bifid ureter with calculi which is asymptomatic unless complicated by infection, reflux, calculi or malignancy. The diagnosis is often missed at intravenous urography (IVU) and US because the ipsilateral ureter and kidney are grossly normal. In this case the diagnosis was established with ultrasound (US) and mainly with multidetector computerized tomography (MDCT) imaging using multiplanar reformats and 3-D reconstructions which were unique to this case. MDCT scans not only revealed the exact diagnosis and anatomic relationships but also ruled out other pathologies included in the differential diagnosis as well, such as ureter and bladder diverticula. PMID:24765338

  19. Assessment of microembolization associated with revascularization in acute myocardial infarction: MDCT cardiac perfusion and function study.

    PubMed

    Saeed, Maythem; Hetts, Steven W; Do, Loi; Wilson, Mark W

    2013-12-01

    To use multi-detector computed tomography (MDCT) for assessing the effects of coronary microemboli on pre-existing acute myocardial infarct (AMI) and to compare this pathology to LAD microembolization and occlusion/reperfusion. An angioplasty balloon catheter was placed in the LAD coronary artery of pigs under X-ray guidance. Four animals served as controls without intervention (group A) and an additional 24 animals (8/group) were subjected to microembolization (group B), occlusion/reperfusion (group C) or combination of the two insults (group D). MDCT was used to assess perfusion, LV function and viability. At postmortem, the LV sections were stained with hematoxylin/eosin and triphenyltetrazolium chloride (TTC). Dynamic perfusion and helical cine MDCT demonstrated decline in regional LV perfusion and function, respectively, after all interventions. MDCT showed significant differences in ejection fraction between groups: A = 57.5 ± 4.7%, B = 40.3 ± 0.5% P < 0.05, C = 34.9 ± 1.3% P < 0.05 and D = 30.7 ± 1.2% P < 0.05, while viability MDCT demonstrated differences in enhancement patterns and extents of damage between the groups (B = 9.1 ± 0.4% LV mass, C = 11.9 ± 0.7% and D = 16.2 ± 1.2%, P < 0.05) and extent of microvascular obstruction (MVO) (group C = 3.2 ± 1.0% LV mass versus D = 5.2 ± 0.7%, P < 0.01). DE-MDCT overestimated all types of myocardial damage compared with TTC, but showed a close correlation (r > 0.7). Microscopic examination confirmed the presence of patchy and contiguous necrosis, MVO, edema and calcium deposits. Dynamic and helical cine MDCT imaging can grade LV dysfunction and perfusion deficit, respectively. DE-MDCT demonstrated a large and persistent MVO zone after microembolization of pre-existing AMI. Furthermore, it has the potential to visualize patchy microinfarct, detect perfusion deficits and dysfunction at the border zone after microembolization of pre-existing AMI.

  20. A study of the anatomy and injection techniques of the ovine stifle by positive contrast arthrography, computed tomography arthrography and gross anatomical dissection.

    PubMed

    Vandeweerd, Jean-Michel; Kirschvink, Nathalie; Muylkens, Benoit; Depiereux, Eric; Clegg, Peter; Herteman, Nicolas; Lamberts, Matthieu; Bonnet, Pierre; Nisolle, Jean-Francois

    2012-08-01

    Although ovine stifle models are commonly used to study osteoarthritis, meniscal pathology and cruciate ligament injuries and repair, there is little information about the anatomy of the joint or techniques for synovial injections. The objectives of this study were to improve anatomical knowledge of the synovial cavities of the ovine knee and to compare intra-articular injection techniques. Synovial cavities of 24 cadaver hind limbs from 12 adult sheep were investigated by intra-articular resin, positive-contrast arthrography, computed tomography (CT) arthrography and gross anatomical dissection. Communication between femoro-patellar, medial femoro-tibial and lateral femoro-tibial compartments occurred in all cases. The knee joint should be considered as one synovial structure with three communicating compartments. Several unreported features were observed, including a communication between the medial femoro-tibial and lateral femoro-tibial compartments and a latero-caudal recess of the lateral femoro-tibial compartment. No intermeniscal ligament was identified. CT was able to define many anatomical features of the stifle, including the anatomy of the tendinous synovial recess on the lateral aspect of the proximal tibia under the combined tendon of the peroneus tertius, extensor longus digitorum and extensor digiti III proprius. An approach for intra-articular injection into this recess (the subtendinous technique) was assessed and compared with the retropatellar and paraligamentous techniques. All three injection procedures were equally successful, but the subtendinous technique appeared to be most appropriate for synoviocentesis and for injections in therapeutic research protocols with less risk of damaging the articular cartilage.

  1. Arthrography of the traumatized wrist: correlation with radiography and the carpal instability series

    SciTech Connect

    Levinsohn, E.M.; Palmer, A.K.

    1983-03-01

    Arthrography with fluoroscopic monitoring was used to assess the soft tissues of the wrist in 100 patients who had chronic traumatic pain but did not have rheumatoid arthritis. Findings were correlated with plain radiographs and the carpal instability series. Arthrograms were normal in 26% of cases and demonstrated perforation of the triangular fibrocartilage in 26%, radiocarpal-midcarpal communication in 30%, capsular lesions in 31%, lymphatic opacification in 12%, and tendon sheath filling in 10%. Communication between the radiocarpal and pisiform-troiquetral compartments, a normal finding, was seen in 69%. There was a significant association between perforation of the triangular fibrocartilage and both ulna-plus variance and carpal instability.

  2. Three-dimensional MDCT angiography of splanchnic arteries: pearls and pitfalls.

    PubMed

    Dohan, A; Dautry, R; Guerrache, Y; Fargeaudou, Y; Boudiaf, M; Le Dref, O; Sirol, M; Soyer, P

    2015-02-01

    Fast scanning along with high resolution of multidetector computed tomography (MDCT) have expanded the role of non-invasive imaging of splanchnic arteries. Advancements in both MDCT scanner technology and three-dimensional (3D) imaging software provide a unique opportunity for non-invasive investigation of splanchnic arteries. Although standard axial computed tomography (CT) images allow identification of splanchnic arteries, visualization of small or distal branches is often limited. Similarly, a comprehensive assessment of the complex anatomy of splanchnic arteries is often beyond the reach of axial images. However, the submillimeter collimation that can be achieved with MDCT scanners now allows the acquisition of true isotropic data so that a high spatial resolution is now maintained in any imaging plane and in 3D mode. This ability to visualize the complex network of splanchnic arteries using 3D rendering and multiplanar reconstruction is of major importance for an optimal analysis in many situations. The purpose of this review is to discuss and illustrate the role of 3D MDCT angiography in the detection and assessment of abnormalities of splanchnic arteries as well as the limitations of the different reconstruction techniques. PMID:24994585

  3. Three-dimensional MDCT angiography of splanchnic arteries: pearls and pitfalls.

    PubMed

    Dohan, A; Dautry, R; Guerrache, Y; Fargeaudou, Y; Boudiaf, M; Le Dref, O; Sirol, M; Soyer, P

    2015-02-01

    Fast scanning along with high resolution of multidetector computed tomography (MDCT) have expanded the role of non-invasive imaging of splanchnic arteries. Advancements in both MDCT scanner technology and three-dimensional (3D) imaging software provide a unique opportunity for non-invasive investigation of splanchnic arteries. Although standard axial computed tomography (CT) images allow identification of splanchnic arteries, visualization of small or distal branches is often limited. Similarly, a comprehensive assessment of the complex anatomy of splanchnic arteries is often beyond the reach of axial images. However, the submillimeter collimation that can be achieved with MDCT scanners now allows the acquisition of true isotropic data so that a high spatial resolution is now maintained in any imaging plane and in 3D mode. This ability to visualize the complex network of splanchnic arteries using 3D rendering and multiplanar reconstruction is of major importance for an optimal analysis in many situations. The purpose of this review is to discuss and illustrate the role of 3D MDCT angiography in the detection and assessment of abnormalities of splanchnic arteries as well as the limitations of the different reconstruction techniques.

  4. Comparison of Indirect MR Arthrography With Conventional MRI in the Diagnosis of Knee Pathologies in Patients With Knee Pain

    PubMed Central

    Babaei Jandaghi, Ali; Mardani-Kivi, Mohsen; Mirbolook, Ahmadreza; Emami-Meybodi, Mohammad Kazem; Mohammadzadeh, Solmaz; Farahmand, Maral

    2016-01-01

    Background Knee pain is a common problem in the general population. In order to determine the extent of the injury and the appropriate treatment, MRI provides the most accurate imaging method. This may be done through conventional MRI techniques or by injecting a contrast material (MR arthrography). Objectives The purpose of this study was to compare the diagnostic value of these two methods. Patients and Methods The study involved the diagnostic evaluation on 60 patients with knee pain who received treatment over the course of a one-year period. Referred patients were randomly divided into two groups: indirect MR arthrography was performed on one group, and conventional MRI was performed on the other group. Both groups then underwent arthroscopy. The results from both groups were compared with the arthroscopic findings. Results In all of the pathologies studied, the sensitivity, specificity, and the positive and negative predictive values were evaluated. A high rate of accuracy was found between MR arthrography and arthroscopy (P < 0.05) for all knee injuries, however a similar rate of accuracy between conventional MRI and arthroscopy was only seen in patients with damage to the posterior cruciate ligament (PCL), the tibio-femoral articular cartilage, and patella chondromalacia (P < 0.05). The highest rate of accuracy was seen in cases where indirect MR arthrography was used for the diagnosis of anterior cruciate ligament (ACL) damage (K = 1). Conclusions Our results have shown that indirect MR arthrography had greater diagnostic accuracy in regards to the sensitivity, specificity, and positive and negative predictive values than conventional MRI in knee pathologies.

  5. Comparison of Indirect MR Arthrography With Conventional MRI in the Diagnosis of Knee Pathologies in Patients With Knee Pain

    PubMed Central

    Babaei Jandaghi, Ali; Mardani-Kivi, Mohsen; Mirbolook, Ahmadreza; Emami-Meybodi, Mohammad Kazem; Mohammadzadeh, Solmaz; Farahmand, Maral

    2016-01-01

    Background Knee pain is a common problem in the general population. In order to determine the extent of the injury and the appropriate treatment, MRI provides the most accurate imaging method. This may be done through conventional MRI techniques or by injecting a contrast material (MR arthrography). Objectives The purpose of this study was to compare the diagnostic value of these two methods. Patients and Methods The study involved the diagnostic evaluation on 60 patients with knee pain who received treatment over the course of a one-year period. Referred patients were randomly divided into two groups: indirect MR arthrography was performed on one group, and conventional MRI was performed on the other group. Both groups then underwent arthroscopy. The results from both groups were compared with the arthroscopic findings. Results In all of the pathologies studied, the sensitivity, specificity, and the positive and negative predictive values were evaluated. A high rate of accuracy was found between MR arthrography and arthroscopy (P < 0.05) for all knee injuries, however a similar rate of accuracy between conventional MRI and arthroscopy was only seen in patients with damage to the posterior cruciate ligament (PCL), the tibio-femoral articular cartilage, and patella chondromalacia (P < 0.05). The highest rate of accuracy was seen in cases where indirect MR arthrography was used for the diagnosis of anterior cruciate ligament (ACL) damage (K = 1). Conclusions Our results have shown that indirect MR arthrography had greater diagnostic accuracy in regards to the sensitivity, specificity, and positive and negative predictive values than conventional MRI in knee pathologies. PMID:27625998

  6. Coronary artery dissection with rupture of aortic valve commissure following type A aortic dissection: the role of 64-slice MDCT.

    PubMed

    Das, K M; Abdou, Sayed M; El-Menyar, Ayman; Ayman, El Menyar; Khulaifi, A A; Nabti, A L

    2008-01-01

    A rare case of bilateral coronary artery dissection with rupture of aortic valve commissure following type A aortic dissection is described. 64-slice multidetector computed tomography (MDCT) was able to demonstrate both this findings along with involvement of other neck vessels. TEE demonstrated the severity and mechanisms of aortic valve damage and assisted the surgeon in valve repair. MDCT has played an invaluable role in the diagnosis of the abnormal details of such life-threatening vascular complications. PMID:18384568

  7. MDCT Versus MRI Assessment of Tumor Response After Transarterial Chemoembolization for the Treatment of Hepatocellular Carcinoma

    SciTech Connect

    Kloeckner, Roman; Otto, Gerd; Biesterfeld, Stefan; Oberholzer, Katja; Dueber, Christoph; Pitton, Michael B.

    2010-06-15

    The purpose of this study was to compare the ability of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) to evaluate treatment results after transarterial chemoembolization (TACE), with a special focus on the influence of Lipiodol on calculation of tumor necrosis according to EASL criteria. A total of 115 nodules in 20 patients (17 males, 3 females; 69.5 {+-} 9.35 years) with biopsy-proven hepatocellular carcinoma were treated with TACE. Embolization was performed using a doxorubicin-Lipiodol emulsion (group I) or DC Beads loaded with doxorubicin (group II). Follow-up included triphasic contrast-enhanced 64-row MDCT (collimation, 0.625 mm; slice, 3 mm; contrast bolus, 120 ml iomeprol; delay by bolus trigger) and contrast-enhanced MRI (T1 native, T2 native; five dynamic contrast-enhanced phases; 0.1 mmol/kg body weight gadolinium-DTPA; slice thickness, 4 mm). Residual tumor and the extent of tumor necrosis were evaluated according to EASL. Contrast enhancement within tumor lesions was suspected to represent vital tumor. In the Lipiodol-based TACE protocol, MDCT underestimated residual viable tumor compared to MRI, due to Lipiodol artifacts (23.2% vs 47.7% after first, 11.9% vs 31.2% after second, and 11.4% vs 23.7% after third TACE; p = 0.0014, p < 0.001, and p < 0.001, respectively). In contrast to MDCT, MRI was completely free of any artifacts caused by Lipiodol. In the DC Bead-based Lipiodol-free TACE protocol, MRI and CT showed similar residual tumor and rating of treatment results (46.4% vs 41.2%, 31.9 vs 26.8%, and 26.0% vs 25.6%; n.s.). In conclusion, MRI is superior to MDCT for detection of viable tumor residuals after Lipiodol-based TACE. Since viable tumor tissue is superimposed by Lipiodol artifacts in MDCT, MRI is mandatory for reliable decision-making during follow-up after Lipiodol-based TACE protocols.

  8. Potential Utility of a Combined Approach with US and MR Arthrography to Image Medial Elbow Pain in Baseball Players.

    PubMed

    Roedl, Johannes B; Gonzalez, Felix M; Zoga, Adam C; Morrison, William B; Nevalainen, Mika T; Ciccotti, Michael G; Nazarian, Levon N

    2016-06-01

    Purpose To evaluate a combined imaging approach with both ultrasonography (US; conventional US and valgus stress US) and magnetic resonance (MR) arthrography in baseball players with medial elbow pain. Materials and Methods Institutional review board approval was obtained and the requirement for informed consent was waived. The study is compliant with HIPAA. Baseball players with medial elbow pain underwent US in addition to MR arthrography. Findings were assessed with each modality alone and both combined in this retrospective investigation. For the evaluation of ulnar collateral ligament (UCL) tears with stress US, the interval gapping of the medial elbow joint was measured between rest and valgus stress both at the injured and at the uninjured (contralateral) elbow. Surgical or arthroscopic correlation was available as the so-called gold standard. McNemar tests compared the accuracies of the imaging modalities. Results In this study, 144 baseball players had 191 findings of medial elbow pain, including 53 UCL tears. With stress US, joint gapping at the injured elbow greater than 1.0 mm compared with the contralateral elbow yielded a sensitivity, specificity, and accuracy of 96%, 81%, and 87%, respectively, for diagnosing UCL tears. With MR arthrography, the sensitivity, specificity, and accuracy for UCL tears were 81%, 91%, and 88%, respectively, and increased to 96% (P = .013, McNemar test), 99% (P = .023), and 98% (P < .001), respectively, when combined with US to a dual modality MR and US approach. For 31 patients with ulnar neuritis, the sensitivity, specificity, and accuracy increased from 74%, 92%, and 88%, respectively, with MR arthrography alone to 90% (P = .07, McNemar test), 100% (P < .001), and 98% (P < .001) combined with US. For the 59 myotendinous and the 48 osteochondral diagnoses, the sensitivity, specificity, and accuracy with MR arthrography alone were 93%, 93%, and 93%, and 94%, 98%, and 97%, respectively, with no additional diagnostic value

  9. Potential Utility of a Combined Approach with US and MR Arthrography to Image Medial Elbow Pain in Baseball Players.

    PubMed

    Roedl, Johannes B; Gonzalez, Felix M; Zoga, Adam C; Morrison, William B; Nevalainen, Mika T; Ciccotti, Michael G; Nazarian, Levon N

    2016-06-01

    Purpose To evaluate a combined imaging approach with both ultrasonography (US; conventional US and valgus stress US) and magnetic resonance (MR) arthrography in baseball players with medial elbow pain. Materials and Methods Institutional review board approval was obtained and the requirement for informed consent was waived. The study is compliant with HIPAA. Baseball players with medial elbow pain underwent US in addition to MR arthrography. Findings were assessed with each modality alone and both combined in this retrospective investigation. For the evaluation of ulnar collateral ligament (UCL) tears with stress US, the interval gapping of the medial elbow joint was measured between rest and valgus stress both at the injured and at the uninjured (contralateral) elbow. Surgical or arthroscopic correlation was available as the so-called gold standard. McNemar tests compared the accuracies of the imaging modalities. Results In this study, 144 baseball players had 191 findings of medial elbow pain, including 53 UCL tears. With stress US, joint gapping at the injured elbow greater than 1.0 mm compared with the contralateral elbow yielded a sensitivity, specificity, and accuracy of 96%, 81%, and 87%, respectively, for diagnosing UCL tears. With MR arthrography, the sensitivity, specificity, and accuracy for UCL tears were 81%, 91%, and 88%, respectively, and increased to 96% (P = .013, McNemar test), 99% (P = .023), and 98% (P < .001), respectively, when combined with US to a dual modality MR and US approach. For 31 patients with ulnar neuritis, the sensitivity, specificity, and accuracy increased from 74%, 92%, and 88%, respectively, with MR arthrography alone to 90% (P = .07, McNemar test), 100% (P < .001), and 98% (P < .001) combined with US. For the 59 myotendinous and the 48 osteochondral diagnoses, the sensitivity, specificity, and accuracy with MR arthrography alone were 93%, 93%, and 93%, and 94%, 98%, and 97%, respectively, with no additional diagnostic value

  10. MDCT-Guided Transthoracic Needle Aspiration Biopsy of the Lung Using the Transscapular Approach

    SciTech Connect

    Rossi, Umberto G. Seitun, Sara; Ferro, Carlo

    2011-02-15

    The purpose of this study is to report our preliminary experience using MDCT-guided percutaneous transthoracic needle aspiration biopsy using the transscapular approach in the upper posterolateral lung nodules, an area that it is difficult or hazardous to reach with the conventional approach. Five patients underwent CT-guided percutaneous transthoracic needle aspiration biopsy of the lung via the transscapular approach. A coaxial needle technique was used in all patients. Biopsy was successful in all patients. No major complications were encountered. One patient developed a minimal pneumothorax next to the lesion immediately after biopsy, which resolved spontaneously. MDCT-guided percutaneous transthoracic needle aspiration biopsy of the lung via the transscapular approach is an effective and safe procedure that reduces the risk of pneumothorax in selected patients.

  11. Use of intra-articular carbon dioxide and air for MR arthrography: a feasibility study.

    PubMed

    Maes, Robbert M; Morrison, William B; Lewin, Jonathan S; Duerk, Jeffrey L; Kiewiet, Cunera J M; Wacker, Frank K

    2006-01-01

    During animal experiments, carbon dioxide (CO(2)) and air were used as a novel contrast agent for direct magnetic resonance arthrography (MRAr). MRAr was performed after injection of CO(2) and air in the knee joints of two pigs. MR images of phantoms containing air, CO(2) and nitrogen were compared. After intra-articular injection, both present as a signal void on various sequences and permit sharp delineation of cartilage and other adjacent structures. Despite the potential for artefact generation, only a slight susceptibility artefact was seen after injection of CO(2) and air. In phantom experiments, air, CO(2) and nitrogen demonstrated identical slight regular susceptibility artefacts at the phantom margins. CO(2) MRAr can yield high contrast between cartilage, ligaments and synovium relative to the joint compartment. Therefore, this technique might be useful as an investigational method for the evaluation of cartilage surface lesions and possibly as an alternative contrast agent for clinical use.

  12. Reperfusion injury components and manifestations determined by cardiovascular MR and MDCT imaging

    PubMed Central

    Saeed, Maythem; Hetts, Steve; Wilson, Mark

    2010-01-01

    Advances in magnetic resonance (MR) and computed tomography (CT) imaging have improved visualization of acute and scar infarct. Over the past decade, there have been and continues to be many significant technical advancements in cardiac MR and multi-detector computed tomography (MDCT) technologies. The strength of MR imaging relies on a variety of pulse sequences and the ability to noninvasively provide information on myocardial structure, function and perfusion in a single imaging session. The recent technical developments may also allow CT technologies to rise to the forefront for evaluating clinical ischemic heart disease. Components of reperfusion injury including myocardial edema, hemorrhage, calcium deposition and microvascular obstruction (MO) have been demonstrated using MR and CT technologies. MR imaging can be used serially and noninvasively in assessing acute and chronic consequences of reperfusion injury because there is no radiation exposure or administration of radioactive materials. MDCT is better suited for assessing coronary artery stenosis and as an alternative technique for assessing viability in patients where MR imaging is contraindicated. Changes in left ventricular (LV) volumes and function measured on cine MR are directly related to infarct size measured on delayed contrast enhanced images. Recent MR studies found that transmural infarct, MO and peri-infarct zone are excellent predictors of poor post-infarct recovery and mortality. Recent MR studies provided ample evidence that growth factor genes and stem cells delivered locally have beneficial effects on myocardial viability, perfusion and function. The significance of deposited calcium in acute infarct detected on MDCT requires further studies. Cardiac MR and MDCT imaging have the potential for assessing reperfusion injury components and manifestations. PMID:21160735

  13. Coronary artery bypass grafts and MDCT imaging: what to know and what to look for.

    PubMed

    Marano, Riccardo; Liguori, Carlo; Rinaldi, Pierluigi; Storto, Maria Luigia; Politi, Marco Angelo; Savino, Giancarlo; Bonomo, Lorenzo

    2007-12-01

    Multi-detector row CT (MDCT) scanners with high spatial and temporal resolutions are now available and are increasingly used for non-invasive assessment of vascular disease, including coronary arteries and coronary artery bypass grafts (CABG). Follow-up of patients who have previously undergone surgical revascularization for coronary artery disease is nowadays one of the main applications of MDCT. Thanks to the continuous technical evolution of the CT scanners, it is now possible to scan the heart and the full anatomic extent of grafts with sub-millimeter slice-thickness within a single breath-hold. In the evaluation of these patients, it is important for the radiologist to be familiar with the different types of grafts and surgical techniques to know the main characteristics of each graft type and what to look for in the assessment of a patient who has undergone coronary artery surgical revascularization. This review summarizes some surgical aspects, the biological characteristics of conduits, and the main technical MDCT features, and describes the CABG anatomy together with some typical CT findings. PMID:17874112

  14. [Double-contrast arthrography in chondropathia patellae--clinical and experimental study on pathogenesis and diagnosis (author's transl)].

    PubMed

    Reichelt, A; Hehne, H J; Rau, W S; Schlageter, M

    1979-10-01

    This study is based on the evaluation of 250 arthrographies of the patellofemoral joint ("défilé" arthrographs in Ficat's terminology) which were performed because of clinical suspicion of chondropathia patellae and which could be controlled intraoperatively in 30 cases, as well as on examinations employing an etching paste as used in metallurgy and performed on 20 knee-joints of corpses. 46% of the arthrographies showed a ridge-shaped cartilaginous thickening which was not pre-modelled in the osseous structure and which separated the medial facette into a paramedian and a marginal segment and correlated with chondromalacia to a greater degree than patellar dysplasias or secondary osseous changes. This variant, which could not be detected by plain roentgenography, must be considered as a pre-arthrotic deformity on account of the high point-shaped pressure load on the ridge. The findings were fully confirmed by macroscopic examination of the postmortem material.

  15. [A combination of conventional single contrast arthrography with arthro-CT of the shoulder--an evaluation of 78 cases].

    PubMed

    Will, C H; Zander, H; Chmielewski, W; Koop, H

    1993-09-01

    For the diagnosis of traumatic shoulder lesions, 78 patients have been examined by conventional single contrast arthrography with subsequent CT. For 26 patients, it was possible to compare the radiological diagnosis with the arthroscopic or surgical findings. The combination of both diagnostic methods provided a high sensitivity (94%) and specificity (100%) for lesions of the ventral or dorsal limbus. Ruptures of the rotator cuff showed a sensitivity of 60% and a specificity of 89%. An unsatisfying sensitivity (60%) with high specificity (95.6%) was observed in the diagnosis of the ventral capsula. A retrospective screening of the roentgenography showed a good detectable leak of contrast medium, which was misinterpreted as being an artefact. All in all, the combination of conventional arthrography in mono-contrast and CT in daily routine should be recommended the diagnosis of traumatic shoulder lesions since it is easy to use, is of low inconvenience for the patient, and provides a high level of information.

  16. Coronary fly-through or virtual angioscopy using dual-source MDCT data.

    PubMed

    van Ooijen, Peter M A; de Jonge, Gonda; Oudkerk, Matthijs

    2007-11-01

    Coronary fly-through or virtual angioscopy (VA) has been studied ever since its invention in 2000. However, application was limited because it requires an optimal computed tomography (CT) scan and time-consuming post-processing. Recent advances in post-processing software facilitate easy construction of VA, but until now image quality was insufficient in most patients. The introduction of dual-source multidetector CT (MDCT) could enable VA in all patients. Twenty patients were scanned using a dual-source MDCT (Definition, Siemens, Forchheim, Germany) using a standard coronary artery protocol. Post-processing was performed on an Aquarius Workstation (TeraRecon, San Mateo, Calif.). Length travelled per major branch was recorded in millimetres, together with the time required in minutes. VA could be performed in every patient for each of the major coronary arteries. The mean (range) length of the automated fly-through was 80 (32-107) mm for the left anterior descending (LAD), 75 (21-116) mm for the left circumflex artery (LCx), and 109 (21-190) mm for the right coronary artery (RCA). Calcifications and stenoses were visualised, as well as most side branches. The mean time required was 3 min for LAD, 2.5 min for LCx, and 2 min for the RCA. Dual-source MDCT allows for high quality visualisation of the coronary arteries in every patient because scanning with this machine is independent of the heart rate. This is clearly shown by the successful VA in all patients. Potential clinical value of VA should be determined in the near future. PMID:17562048

  17. Juxtapapillary duodenal diverticula: MDCT findings in 1010 patients and proposal for a new classification.

    PubMed

    Wiesner, W; Beglinger, Ch; Oertli, D; Steinbrich, W

    2009-01-01

    The aim of this study is to analyze the MDCT findings of juxtapapillary duodenal diverticula (JPDD) and to propose a new radiological classification. CT-examinations of 1010 consecutive patients, all examined by 16-row MDCT of the abdomen over a time period of 20 months were retrospectively analyzed. All study patients were examined by triple phase CT (native, arterial and portal venous CT scan) of the abdomen and all recieved positive oral contrast prior to the examination. Thirty-three patients showed a juxtapapillary duodenal diverticulum, which could be seen on all CT scans, but jusually was depicted most clearly on the thin collimated arterial phase CT images. Size of diverticula range from 4 mm to 4.5 cm (mean 1.7 cm). In 17 cases the diverticulum was located ventrally to the vaterian sphincter complex, extending less or more into the pancreas at the site where the dorsal and the ventral anlage of the pancreas have fused (type I). 12 diverticula were located dorsally to the sphincter complex (type II). Three patients presented with a bilobated juxtapapillary diverticulum extending to both sides, ventrally and dorsally (type III) and one patient showed a little diverticulum ventrally to the minor papilla (type IV).Three patients presented with food impaction in the diverticulum but only one of these patients with a large IPDD showed a Lemmel-syndrome, whereas the other three patients with non-calculous extrahepatic cholostasis showed larger diverticula without food impaction. MDCT allows to identify four different types of juxtapapillary duodenal diverticula and using the proposed classification may be helpful for a more exact, anatomy based radiological description of this CT finding.

  18. Immunomodulation over the course of experimental Arthrographis kalrae infection in mice.

    PubMed

    Nagashima, Luciene Airy; Sano, Ayako; de Almeida Araújo, Eduardo José; Álvares E Silva, Paula Leonello; Assolini, João Paulo; Itano, Eiko Nakagawa

    2016-10-01

    Arthrographis kalrae is occasionally described as an opportunistic human pathogen. This study investigated the immune response to A. kalrae during murine experimental infection (7, 14, 28 and 56 days post infection). The fungal load was higher in the early phase and mice presented with neurological syndrome over the course of the infection. There was a gradual increase in the level of anti-A. kalrae IgG and increased levels of DTH at 14 days. There was decreased IFN-γ (14-56 days) and an increase in IL-4 (7 and 56 days). Decreased levels of cytokines (IFN-γ, IL-4, IL-10 and IL-17) were observed in the brain at 56 days p.i. The results suggest that the immune response during murine A. kalrae infection modulates to the pattern of Th2 response. This study shows for the first time the cytokines and cellular immunomodulation that occur in response to an experimental infection with A. kalrae in mice. PMID:27638123

  19. Can outer-to-outer diameter be used alone in diagnosing appendicitis on 128-slice MDCT?

    PubMed Central

    Yaqoob, Jamal; Idris, Muhammad; Alam, Muhammad Shahbaz; Kashif, Nazia

    2014-01-01

    AIM: To assess the frequency of visualization, position and diameter of normal appendix on 128-slice multidetector computed tomography (MDCT) in adult population. METHODS: Retrospective cross sectional study conducted at Radiology Department, Dallah Hospital, Riyadh, Saudi Arabia from March 2013 to October 2013. Non-enhanced computed tomography scans of abdomen and pelvis of 98 patients presenting with hematuria (not associated with abdominal pain, fever or colonic disease) were reviewed by two radiologists, blinded to patient history. The study group included 55 females and 43 males with overall mean age of 54.7 years (range 21 to 94 years). The coronal reformatted images were reviewed in addition to the axial images. The frequency of visualization of appendix was recorded with assessment of position, diameter and luminal contents. RESULTS: The appendix was recorded as definitely visualized in 99% of patients and mean outer-to-outer diameter of the appendix was 5.6 ± 1.3 mm (range 3.0-11.0 mm). CONCLUSION: MDCT with its multiplanar reformation display is extremely useful for visualization of normal appendix. The normal appendix is very variable in its position and diameter. In the absence of other signs, the diagnosis of acute appendix should not be made solely on outer-to-outer appendiceal diameter. PMID:25550996

  20. Accuracy of Monte Carlo simulations compared to in-vivo MDCT dosimetry

    SciTech Connect

    Bostani, Maryam McMillan, Kyle; Cagnon, Chris H.; McNitt-Gray, Michael F.; Mueller, Jonathon W.; Cody, Dianna D.; DeMarco, John J.

    2015-02-15

    Purpose: The purpose of this study was to assess the accuracy of a Monte Carlo simulation-based method for estimating radiation dose from multidetector computed tomography (MDCT) by comparing simulated doses in ten patients to in-vivo dose measurements. Methods: MD Anderson Cancer Center Institutional Review Board approved the acquisition of in-vivo rectal dose measurements in a pilot study of ten patients undergoing virtual colonoscopy. The dose measurements were obtained by affixing TLD capsules to the inner lumen of rectal catheters. Voxelized patient models were generated from the MDCT images of the ten patients, and the dose to the TLD for all exposures was estimated using Monte Carlo based simulations. The Monte Carlo simulation results were compared to the in-vivo dose measurements to determine accuracy. Results: The calculated mean percent difference between TLD measurements and Monte Carlo simulations was −4.9% with standard deviation of 8.7% and a range of −22.7% to 5.7%. Conclusions: The results of this study demonstrate very good agreement between simulated and measured doses in-vivo. Taken together with previous validation efforts, this work demonstrates that the Monte Carlo simulation methods can provide accurate estimates of radiation dose in patients undergoing CT examinations.

  1. Effect of Low-Dose MDCT and Iterative Reconstruction on Trabecular Bone Microstructure Assessment.

    PubMed

    Kopp, Felix K; Holzapfel, Konstantin; Baum, Thomas; Nasirudin, Radin A; Mei, Kai; Garcia, Eduardo G; Burgkart, Rainer; Rummeny, Ernst J; Kirschke, Jan S; Noël, Peter B

    2016-01-01

    We investigated the effects of low-dose multi detector computed tomography (MDCT) in combination with statistical iterative reconstruction algorithms on trabecular bone microstructure parameters. Twelve donated vertebrae were scanned with the routine radiation exposure used in our department (standard-dose) and a low-dose protocol. Reconstructions were performed with filtered backprojection (FBP) and maximum-likelihood based statistical iterative reconstruction (SIR). Trabecular bone microstructure parameters were assessed and statistically compared for each reconstruction. Moreover, fracture loads of the vertebrae were biomechanically determined and correlated to the assessed microstructure parameters. Trabecular bone microstructure parameters based on low-dose MDCT and SIR significantly correlated with vertebral bone strength. There was no significant difference between microstructure parameters calculated on low-dose SIR and standard-dose FBP images. However, the results revealed a strong dependency on the regularization strength applied during SIR. It was observed that stronger regularization might corrupt the microstructure analysis, because the trabecular structure is a very small detail that might get lost during the regularization process. As a consequence, the introduction of SIR for trabecular bone microstructure analysis requires a specific optimization of the regularization parameters. Moreover, in comparison to other approaches, superior noise-resolution trade-offs can be found with the proposed methods.

  2. Effect of Low-Dose MDCT and Iterative Reconstruction on Trabecular Bone Microstructure Assessment.

    PubMed

    Kopp, Felix K; Holzapfel, Konstantin; Baum, Thomas; Nasirudin, Radin A; Mei, Kai; Garcia, Eduardo G; Burgkart, Rainer; Rummeny, Ernst J; Kirschke, Jan S; Noël, Peter B

    2016-01-01

    We investigated the effects of low-dose multi detector computed tomography (MDCT) in combination with statistical iterative reconstruction algorithms on trabecular bone microstructure parameters. Twelve donated vertebrae were scanned with the routine radiation exposure used in our department (standard-dose) and a low-dose protocol. Reconstructions were performed with filtered backprojection (FBP) and maximum-likelihood based statistical iterative reconstruction (SIR). Trabecular bone microstructure parameters were assessed and statistically compared for each reconstruction. Moreover, fracture loads of the vertebrae were biomechanically determined and correlated to the assessed microstructure parameters. Trabecular bone microstructure parameters based on low-dose MDCT and SIR significantly correlated with vertebral bone strength. There was no significant difference between microstructure parameters calculated on low-dose SIR and standard-dose FBP images. However, the results revealed a strong dependency on the regularization strength applied during SIR. It was observed that stronger regularization might corrupt the microstructure analysis, because the trabecular structure is a very small detail that might get lost during the regularization process. As a consequence, the introduction of SIR for trabecular bone microstructure analysis requires a specific optimization of the regularization parameters. Moreover, in comparison to other approaches, superior noise-resolution trade-offs can be found with the proposed methods. PMID:27447827

  3. Effect of Low-Dose MDCT and Iterative Reconstruction on Trabecular Bone Microstructure Assessment

    PubMed Central

    Baum, Thomas; Nasirudin, Radin A.; Mei, Kai; Garcia, Eduardo G.; Burgkart, Rainer; Rummeny, Ernst J.; Kirschke, Jan S.; Noël, Peter B.

    2016-01-01

    We investigated the effects of low-dose multi detector computed tomography (MDCT) in combination with statistical iterative reconstruction algorithms on trabecular bone microstructure parameters. Twelve donated vertebrae were scanned with the routine radiation exposure used in our department (standard-dose) and a low-dose protocol. Reconstructions were performed with filtered backprojection (FBP) and maximum-likelihood based statistical iterative reconstruction (SIR). Trabecular bone microstructure parameters were assessed and statistically compared for each reconstruction. Moreover, fracture loads of the vertebrae were biomechanically determined and correlated to the assessed microstructure parameters. Trabecular bone microstructure parameters based on low-dose MDCT and SIR significantly correlated with vertebral bone strength. There was no significant difference between microstructure parameters calculated on low-dose SIR and standard-dose FBP images. However, the results revealed a strong dependency on the regularization strength applied during SIR. It was observed that stronger regularization might corrupt the microstructure analysis, because the trabecular structure is a very small detail that might get lost during the regularization process. As a consequence, the introduction of SIR for trabecular bone microstructure analysis requires a specific optimization of the regularization parameters. Moreover, in comparison to other approaches, superior noise-resolution trade-offs can be found with the proposed methods. PMID:27447827

  4. Comparison between a new reconstruction algorithm (OPED) and filtered backprojection (FBP) for MDCT data

    NASA Astrophysics Data System (ADS)

    Renger, Bernhard; No"l, Peter B.; Tischenko, Oleg; Rummeny, Ernst J.; Hoeschen, Christoph

    2012-03-01

    Previously the Orthogonal Polynomial Expansion on the Disk (OPED) algorithm was presented. Further, in prototype experiments in combination with the CT D`or geometry feasibility was demonstrated. In this study we implemented OPED with a clinical Scanner, and evaluated the potential using phantom studies. All studies were acquired on a Siemens Somatom 64 (Erlangen, Germany) scanner, where raw projection data were reconstructed with the conventional FBP reconstruction and the OPED algorithm. OPED allows one to use fan beam geometry directly without any additional procedures such as interpolation or rebinning if using the CT D`or geometry. In particular, OPED describes an approximation of the image function as a sum of polynomials using Chebychev polynomials. For performance evaluation, the Catphan phantom 600 was imaged. OPED Images where reconstructed using C++ and MATLAB® .We measured uniformity, MTF and CNR for different dose levels and compared these to standard FBP images reconstructions with different filter kernels. The integration and interpretation of the MDCT projection data for the OPED algorithm was accomplished. Reconstruction time is about 6 s on Quad-Core 3 GHz Intel Xeon processor. Typical artifacts are reduced when applying OPED. Using OPED the MTF maintains constant over the whole FOV. Uniformity and CNR are equal compared to FBP. Advantages of OPED were demonstrated by applying the algorithm to projections images from a clinical MDCT scanner. In the future, we see OPED applications for low-dose or limited angle geometries to reduce the radiation dose while improving diagnostic quality of the reconstructed slices.

  5. MDCT evaluation of potential living renal donor, prior to laparoscopic donor nephrectomy: What the transplant surgeon wants to know?

    PubMed

    Ghonge, Nitin P; Gadanayak, Satyabrat; Rajakumari, Vijaya

    2014-10-01

    As Laparoscopic Donor Nephrectomy (LDN) offers several advantages for the donor such as lesser post-operative pain, fewer cosmetic concerns and faster recovery time, there is growing global trend towards LDN as compared to open nephrectomy. Comprehensive pre-LDN donor evaluation includes assessment of renal morphology including pelvi-calyceal and vascular system. Apart from donor selection, evaluation of the regional anatomy allows precise surgical planning. Due to limited visualization during laparoscopic renal harvesting, detailed pre-transplant evaluation of regional anatomy, including the renal venous anatomy is of utmost importance. MDCT is the modality of choice for pre-LDN evaluation of potential renal donors. Apart from appropriate scan protocol and post-processing methods, detailed understanding of surgical techniques is essential for the Radiologist for accurate image interpretation during pre-LDN MDCT evaluation of potential renal donors. This review article describes MDCT evaluation of potential living renal donor, prior to LDN with emphasis on scan protocol, post-processing methods and image interpretation. The article laid special emphasis on surgical perspectives of pre-LDN MDCT evaluation and addresses important points which transplant surgeons want to know. PMID:25489130

  6. Effects of iodinated contrast agent, xylocaine and gadolinium concentration on the signal emitted in magnetic resonance arthrography: a samples study*

    PubMed Central

    da Silva, Yvana Lopes Pinheiro; Costa, Rita Zanlorensi Visneck; Pinho, Kátia Elisa Prus; Ferreira, Ricardo Rabello; Schuindt, Sueliton Miyamoto

    2015-01-01

    Objective To investigate the effects of dilution of paramagnetic contrast agent with iodinated contrast and xylocaine on the signal intensity during magnetic resonance arthrography, and to improve the paramagnetic contrast agent concentration utilized in this imaging modality. Materials and Methods Samples specially prepared for the study with three different concentrations of paramagnetic contrast agent diluted in saline, iodinated contrast agent and xylocaine were imaged with fast spin echo T1-weighted sequences with fat saturation. The samples were placed into flasks and graphical analysis of the signal intensity was performed as a function of the paramagnetic contrast concentration. Results As compared with samples of equal concentrations diluted only with saline, the authors have observed an average signal intensity decrease of 20.67% for iodinated contrast agent, and of 28.34% for xylocaine. However, the increased gadolinium concentration in the samples caused decrease in signal intensity with all the dilutions. Conclusion Minimizing the use of iodinated contrast media and xylocaine and/or the use of a gadolinium concentration of 2.5 mmol/L diluted in saline will improve the sensitivity of magnetic resonance arthrography. PMID:25987746

  7. Data compression in wireless sensors network using MDCT and embedded harmonic coding.

    PubMed

    Alsalaet, Jaafar K; Ali, Abduladhem A

    2015-05-01

    One of the major applications of wireless sensors networks (WSNs) is vibration measurement for the purpose of structural health monitoring and machinery fault diagnosis. WSNs have many advantages over the wired networks such as low cost and reduced setup time. However, the useful bandwidth is limited, as compared to wired networks, resulting in relatively low sampling. One solution to this problem is data compression which, in addition to enhancing sampling rate, saves valuable power of the wireless nodes. In this work, a data compression scheme, based on Modified Discrete Cosine Transform (MDCT) followed by Embedded Harmonic Components Coding (EHCC) is proposed to compress vibration signals. The EHCC is applied to exploit harmonic redundancy present is most vibration signals resulting in improved compression ratio. This scheme is made suitable for the tiny hardware of wireless nodes and it is proved to be fast and effective. The efficiency of the proposed scheme is investigated by conducting several experimental tests.

  8. Acute colonic diverticulitis: an update on clinical classification and management with MDCT correlation.

    PubMed

    Barat, Maxime; Dohan, Anthony; Pautrat, Karine; Boudiaf, Mourad; Dautry, Raphael; Guerrache, Youcef; Pocard, Marc; Hoeffel, Christine; Eveno, Clarisse; Soyer, Philippe

    2016-09-01

    Currently, the most commonly used classification of acute colonic diverticulitis (ACD) is the modified Hinchey classification, which corresponds to a slightly more complex classification by comparison with the original description. This modified classification allows to categorize patients with ACD into four major categories (I, II, III, IV) and two additional subcategories (Ia and Ib), depending on the severity of the disease. Several studies have clearly demonstrated the impact of this classification for determining the best therapeutic approach and predicting perioperative complications for patients who need surgery. This review provides an update on the classification of ACD along with a special emphasis on the corresponding MDCT features of the different categories and subcategories. This modified Hinchey classification should be known by emergency physicians, radiologists, and surgeons in order to improve patient care and management because each category has a specific therapeutic approach. PMID:27138434

  9. Radiation exposure of ovarian cancer patients: contribution of CT examinations performed on different MDCT (16 and 64 slices) scanners and image quality evaluation: an observational study.

    PubMed

    Rizzo, Stefania; Origgi, Daniela; Brambilla, Sarah; De Maria, Federica; Foà, Riccardo; Raimondi, Sara; Colombo, Nicoletta; Bellomi, Massimo

    2015-05-01

    The objective of this study is to compare radiation doses given to ovarian cancer patients by different computed tomographies (CTs) and to evaluate association between doses and subjective and objective image quality.CT examinations included were performed either on a 16-slice CT, equipped with automatic z-axis tube current modulation, or on a 64-slice CT, equipped with z-axis, xy-axis modulation, and adaptive statistical iterative algorithm (ASIR). Evaluation of dose included the following dose descriptors: volumetric CT dose index (CTDIvol), dose length product (DLP), and effective dose (E). Objective image noise was evaluated in abdominal aorta and liver. Subjective image quality was evaluated by assessment of image noise, spatial resolution and diagnostic acceptability.Mean and median CTDIvol, DLP, and E; correlation between CTDIvol and DLP and patients' weight; comparison of objective noise for the 2 scanners; association between dose descriptors and subjective image quality.The 64-slice CT delivered to patients 24.5% lower dose (P < 0.0001) than 16-slice CT. There was a significant correlation between all dose descriptors (CTDIvol, DLP, E) and weight (P < 0.0001). Objective noise was comparable for the 2 CT scanners. There was a significant correlation between dose descriptors and image noise for the 64-slice CT, and between dose descriptors and spatial resolution for the 16-slice CT.Current dose reduction systems may reduce radiation dose without significantly affecting image quality and diagnostic acceptability of CT exams. PMID:25929914

  10. Radiation Exposure of Ovarian Cancer Patients: Contribution of CT Examinations Performed on Different MDCT (16 and 64 Slices) Scanners and Image Quality Evaluation

    PubMed Central

    Rizzo, Stefania; Origgi, Daniela; Brambilla, Sarah; De Maria, Federica; Foà, Riccardo; Raimondi, Sara; Colombo, Nicoletta; Bellomi, Massimo

    2015-01-01

    Abstract The objective of this study is to compare radiation doses given to ovarian cancer patients by different computed tomographies (CTs) and to evaluate association between doses and subjective and objective image quality. CT examinations included were performed either on a 16-slice CT, equipped with automatic z-axis tube current modulation, or on a 64-slice CT, equipped with z-axis, xy-axis modulation, and adaptive statistical iterative algorithm (ASIR). Evaluation of dose included the following dose descriptors: volumetric CT dose index (CTDIvol), dose length product (DLP), and effective dose (E). Objective image noise was evaluated in abdominal aorta and liver. Subjective image quality was evaluated by assessment of image noise, spatial resolution and diagnostic acceptability. Mean and median CTDIvol, DLP, and E; correlation between CTDIvol and DLP and patients’ weight; comparison of objective noise for the 2 scanners; association between dose descriptors and subjective image quality. The 64-slice CT delivered to patients 24.5% lower dose (P < 0.0001) than 16-slice CT. There was a significant correlation between all dose descriptors (CTDIvol, DLP, E) and weight (P < 0.0001). Objective noise was comparable for the 2 CT scanners. There was a significant correlation between dose descriptors and image noise for the 64-slice CT, and between dose descriptors and spatial resolution for the 16-slice CT. Current dose reduction systems may reduce radiation dose without significantly affecting image quality and diagnostic acceptability of CT exams. PMID:25929914

  11. Accuracy of gantry rotation time of less than 300 ms for modern MDCT systems.

    PubMed

    Fukuda, Atsushi; Lin, Pei-Jan Paul; Matsubara, Kosuke; Miyati, Tosiaki

    2015-01-01

    The accuracy of gantry rotation times of less than 300 ms has been assessed for two "state-of-the art" MDCT systems. The rotation time was measured at selected nominal rotation times (275 and 280 ms) with a solid-state detector; Unfors Xi probe. The detector was positioned on the inner bottom of the gantry bore. Because a pair of two successive radiation peaks is necessary for determination of the rotation time, the radiation detection was performed with the helical scan mode of operation. Upon completion of the data acquisition, we determined the peak times with the Unfors Xi View software program to obtain the rotation time. The means and standard deviations of the measured rotation times were 275.3 ± 0.5 and 285.1 ± 0.4 ms, respectively. The inaccuracy of the rotation time was approximately 5 ms at most, which was comparable to that previously reported for slower rotation times.

  12. Comparison of 3.0-T MR vs 3.0-T MR arthrography of the hip for detection of acetabular labral tears and chondral defects in the same patient population

    PubMed Central

    2015-01-01

    Objective: We report our experience in diagnostic sensitivity of 3.0-T conventional MR vs 3.0-T MR arthrography of the hip for detection of acetabular labral tears and chondral defects in the same patient population. Methods: 43 consecutive patients had both conventional hip MR and MR arthrography examinations performed. These examinations were reviewed retrospectively by independent reading of two musculoskeletal radiologists who read the MR and MR arthrogram examinations in a randomized fashion (i.e. MR and MR arthrogram examinations were read at separate sittings and in a randomized fashion so as not to bias reviewers). Scans were assessed for acetabular labral tears and chondral defects. All patients went on to arthroscopy. Results: Of these 43 patients, 40 had acetabular labral tears read by Reader 1 and 39 had acetabular labral tears read by Reader 2 on MR arthrogram, 39 had acetabular labral tears read by Reader 1 and 38 had acetabular labral tears read by Reader 2 on conventional MR examination. There were 42 labral tears in 43 patients at arthroscopy. There were four false-negative labral tears compared with arthroscopy on MR and three false negatives on MR arthrography for Reader 1 and five false negatives on MR and four false negatives on MR arthrography for Reader 2. Each reader had one false-positive labral tear compared with arthroscopy on both MR and MR arthrography. There were 32 acetabular chondral defects at arthroscopy. Reader 1 saw 21 acetabular chondral defects on conventional MR and 27 chondral defects at MR arthrography. Reader 2 saw 19 acetabular chondral defects at conventional MR and 25 acetabular chondral defects on MR arthrography. There were no false-positive readings of chondral defects compared with arthroscopy on MR and one false positive for Reader 1 and two false positives for Reader 2 on MR arthrography as compared with arthroscopy. On conventional MR examination, sensitivities and specificities as compared with arthroscopy were

  13. CT Hounsfield Numbers of Soft Tissues on Unenhanced Abdominal CT Scans: Variability Between Two Different Manufacturers’ MDCT Scanners

    PubMed Central

    Lamba, Ramit; McGahan, John P.; Corwin, Michael T.; Li, Chin-Shang; Tran, Tien; Seibert, J. Anthony; Boone, John M.

    2016-01-01

    OBJECTIVE The purpose of this study is to determine whether Hounsfield numbers of soft tissues on unenhanced abdominal CT of the same patient vary on repeat scans done on two different manufacturers’ MDCT scanners. MATERIALS AND METHODS A database search was performed to identify patients older than 18 years who underwent unenhanced CT of the abdomen and pelvis performed both on a Volume CT (GE Healthcare) and a Definition AS Plus (Siemens Healthcare) 64-MDCT scanner within 12 months of each other. After excluding those patients for whom Hounsfield unit measurements would be affected by mitigating factors, 48 patients (mean age, 58.8 years) were identified. Hounsfield unit measurements were obtained in nine different soft-tissue anatomic locations on each scan, and the location of these sites was kept identical on each scan pair. Data were analyzed to evaluate Hounsfield unit differences between these scanners. RESULTS In general, there was a low consistency in the Hounsfield unit measurements for each of these sites on scans obtained by the two scanners, with the subcutaneous fat in the left posterolateral flank showing the lowest correlation (intraclass correlation coefficient, 0.198). There were differences in the Hounsfield unit measurements obtained in all anatomic sites on scans obtained by both scanners. Mean Hounsfield unit measurements obtained on the Definition AS Plus scanner were lower than those obtained on the Volume CT scanner, with the intriguing exception of the anterior midline subcutaneous fat Hounsfield unit measurements, which were higher on the Definition AS Plus scanner. All differences were statistically significant (p < 0.05). CONCLUSION Hounsfield unit measurements for unenhanced abdominal soft tissues of the same patient vary between scanners of two common MDCT manufacturers. PMID:25341139

  14. Automated diagnosis of interstitial lung diseases and emphysema in MDCT imaging

    NASA Astrophysics Data System (ADS)

    Fetita, Catalin; Chang Chien, Kuang-Che; Brillet, Pierre-Yves; Prêteux, Françoise

    2007-09-01

    Diffuse lung diseases (DLD) include a heterogeneous group of non-neoplasic disease resulting from damage to the lung parenchyma by varying patterns of inflammation. Characterization and quantification of DLD severity using MDCT, mainly in interstitial lung diseases and emphysema, is an important issue in clinical research for the evaluation of new therapies. This paper develops a 3D automated approach for detection and diagnosis of diffuse lung diseases such as fibrosis/honeycombing, ground glass and emphysema. The proposed methodology combines multi-resolution 3D morphological filtering (exploiting the sup-constrained connection cost operator) and graph-based classification for a full characterization of the parenchymal tissue. The morphological filtering performs a multi-level segmentation of the low- and medium-attenuated lung regions as well as their classification with respect to a granularity criterion (multi-resolution analysis). The original intensity range of the CT data volume is thus reduced in the segmented data to a number of levels equal to the resolution depth used (generally ten levels). The specificity of such morphological filtering is to extract tissue patterns locally contrasting with their neighborhood and of size inferior to the resolution depth, while preserving their original shape. A multi-valued hierarchical graph describing the segmentation result is built-up according to the resolution level and the adjacency of the different segmented components. The graph nodes are then enriched with the textural information carried out by their associated components. A graph analysis-reorganization based on the nodes attributes delivers the final classification of the lung parenchyma in normal and ILD/emphysematous regions. It also makes possible to discriminate between different types, or development stages, among the same class of diseases.

  15. A multiscale MDCT image-based breathing lung model with time-varying regional ventilation

    SciTech Connect

    Yin, Youbing; Choi, Jiwoong; Hoffman, Eric A.; Tawhai, Merryn H.; Lin, Ching-Long

    2013-07-01

    A novel algorithm is presented that links local structural variables (regional ventilation and deforming central airways) to global function (total lung volume) in the lung over three imaged lung volumes, to derive a breathing lung model for computational fluid dynamics simulation. The algorithm constitutes the core of an integrative, image-based computational framework for subject-specific simulation of the breathing lung. For the first time, the algorithm is applied to three multi-detector row computed tomography (MDCT) volumetric lung images of the same individual. A key technique in linking global and local variables over multiple images is an in-house mass-preserving image registration method. Throughout breathing cycles, cubic interpolation is employed to ensure C{sub 1} continuity in constructing time-varying regional ventilation at the whole lung level, flow rate fractions exiting the terminal airways, and airway deformation. The imaged exit airway flow rate fractions are derived from regional ventilation with the aid of a three-dimensional (3D) and one-dimensional (1D) coupled airway tree that connects the airways to the alveolar tissue. An in-house parallel large-eddy simulation (LES) technique is adopted to capture turbulent-transitional-laminar flows in both normal and deep breathing conditions. The results obtained by the proposed algorithm when using three lung volume images are compared with those using only one or two volume images. The three-volume-based lung model produces physiologically-consistent time-varying pressure and ventilation distribution. The one-volume-based lung model under-predicts pressure drop and yields un-physiological lobar ventilation. The two-volume-based model can account for airway deformation and non-uniform regional ventilation to some extent, but does not capture the non-linear features of the lung.

  16. A Numerical Study of Heat and Water Vapor Transfer in MDCT-Based Human Airway Models

    PubMed Central

    Wu, Dan; Tawhai, Merryn H.; Hoffman, Eric A.; Lin, Ching-Long

    2014-01-01

    A three-dimensional (3D) thermo-fluid model is developed to study regional distributions of temperature and water vapor in three multi-detector row computed-tomography (MDCT)-basedhuman airwayswith minute ventilations of 6, 15 and 30 L/min. A one-dimensional (1D) model is also solved to provide necessary initial and boundary conditionsforthe 3D model. Both 3D and 1D predicted temperature distributions agree well with available in vivo measurement data. On inspiration, the 3D cold high-speed air stream is split at the bifurcation to form secondary flows, with its cold regions biased toward the inner wall. The cold air flowing along the wall is warmed up more rapidly than the air in the lumen center. The repeated splitting pattern of air streams caused by bifurcations acts as an effective mechanism for rapid heat and mass transfer in 3D. This provides a key difference from the 1D model, where heating relies largely on diffusion in the radial direction, thus significantly affecting gradient-dependent variables, such as energy flux and water loss rate. We then propose the correlations for respective heat and mass transfer in the airways of up to 6 generations: Nu=3.504(ReDaDt)0.277, R = 0.841 and Sh=3.652(ReDaDt)0.268, R = 0.825, where Nu is the Nusselt number, Sh is the Sherwood number, Re is the branch Reynolds number, Da is the airway equivalent diameter, and Dt is the tracheal equivalentdiameter. PMID:25081386

  17. Dynamic real-time 4D cardiac MDCT image display using GPU-accelerated volume rendering.

    PubMed

    Zhang, Qi; Eagleson, Roy; Peters, Terry M

    2009-09-01

    Intraoperative cardiac monitoring, accurate preoperative diagnosis, and surgical planning are important components of minimally-invasive cardiac therapy. Retrospective, electrocardiographically (ECG) gated, multidetector computed tomographical (MDCT), four-dimensional (3D + time), real-time, cardiac image visualization is an important tool for the surgeon in such procedure, particularly if the dynamic volumetric image can be registered to, and fused with the actual patient anatomy. The addition of stereoscopic imaging provides a more intuitive environment by adding binocular vision and depth cues to structures within the beating heart. In this paper, we describe the design and implementation of a comprehensive stereoscopic 4D cardiac image visualization and manipulation platform, based on the opacity density radiation model, which exploits the power of modern graphics processing units (GPUs) in the rendering pipeline. In addition, we present a new algorithm to synchronize the phases of the dynamic heart to clinical ECG signals, and to calculate and compensate for latencies in the visualization pipeline. A dynamic multiresolution display is implemented to enable the interactive selection and emphasis of volume of interest (VOI) within the entire contextual cardiac volume and to enhance performance, and a novel color and opacity adjustment algorithm is designed to increase the uniformity of the rendered multiresolution image of heart. Our system provides a visualization environment superior to noninteractive software-based implementations, but with a rendering speed that is comparable to traditional, but inferior quality, volume rendering approaches based on texture mapping. This retrospective ECG-gated dynamic cardiac display system can provide real-time feedback regarding the suspected pathology, function, and structural defects, as well as anatomical information such as chamber volume and morphology.

  18. MDCT Anatomic Assessment of Right Inferior Phrenic Artery Origin Related to Potential Supply to Hepatocellular Carcinoma and its Embolization

    SciTech Connect

    Basile, Antonio Tsetis, Dimitrios; Montineri, Arturo; Puleo, Stefano; Massa Saluzzo, Cesare; Runza, Giuseppe; Coppolino, Francesco; Ettorre, Giovanni Carlo; Patti, Maria Teresa

    2008-03-15

    Purpose. To prospectively assess the anatomic variation of the right inferior phrenic artery (RIPA) origin with multidetector computed tomography (MDCT) scans in relation to the technical and angiographic findings during transcatheter arterial embolization of hepatocellular carcinoma (HCC). Methods. Two hundred patients with hepatocellular carcinomas were examined with 16-section CT during the arterial phase. The anatomy of the inferior phrenic arteries was recorded, with particular reference to their origin. All patients with subcapsular HCC located at segments VII and VIII underwent arteriography of the RIPA with subsequent embolization if neoplastic supply was detected. Results. The RIPA origin was detected in all cases (sensitivity 100%), while the left inferior phrenic artery origin was detected in 187 cases (sensitivity 93.5%). RIPAs originated from the aorta (49%), celiac trunk (41%), right renal artery (5.5%), left gastric artery (4%), and proper hepatic artery (0.5%), with 13 types of combinations with the left IPA. Twenty-nine patients showed subcapsular HCCs in segments VII and VIII and all but one underwent RIPA selective angiography, followed by embolization in 7 cases. Conclusion. MDCT assesses well the anatomy of RIPAs, which is fundamental for planning subsequent cannulation and embolization of extrahepatic RIPA supply to HCC.

  19. The impacts of open-mouth breathing on upper airway space in obstructive sleep apnea: 3-D MDCT analysis.

    PubMed

    Kim, Eun Joong; Choi, Ji Ho; Kim, Kang Woo; Kim, Tae Hoon; Lee, Sang Hag; Lee, Heung Man; Shin, Chol; Lee, Ki Yeol; Lee, Seung Hoon

    2011-04-01

    Open-mouth breathing during sleep is a risk factor for obstructive sleep apnea (OSA) and is associated with increased disease severity and upper airway collapsibility. The aim of this study was to investigate the effect of open-mouth breathing on the upper airway space in patients with OSA using three-dimensional multi-detector computed tomography (3-D MDCT). The study design included a case-control study with planned data collection. The study was performed at a tertiary medical center. 3-D MDCT analysis was conducted on 52 patients with OSA under two experimental conditions: mouth closed and mouth open. Under these conditions, we measured the minimal cross-sectional area of the retropalatal and retroglossal regions (mXSA-RP, mXSA-RG), as well as the upper airway length (UAL), defined as the vertical dimension from hard palate to hyoid. We also computed the volume of the upper airway space by 3-D reconstruction of both conditions. When the mouth was open, mXSA-RP and mXSA-RG significantly decreased and the UAL significantly increased, irrespective of the severity of OSA. However, between the closed- and open-mouth states, there was no significant change in upper airway volume at any severity of OSA. Results suggest that the more elongated and narrow upper airway during open-mouth breathing may aggravate the collapsibility of the upper airway and, thus, negatively affect OSA severity.

  20. Influence of radiation dose and reconstruction algorithm in MDCT assessment of airway wall thickness: A phantom study

    SciTech Connect

    Gomez-Cardona, Daniel; Nagle, Scott K.; Li, Ke; Chen, Guang-Hong; Robinson, Terry E.

    2015-10-15

    Purpose: Wall thickness (WT) is an airway feature of great interest for the assessment of morphological changes in the lung parenchyma. Multidetector computed tomography (MDCT) has recently been used to evaluate airway WT, but the potential risk of radiation-induced carcinogenesis—particularly in younger patients—might limit a wider use of this imaging method in clinical practice. The recent commercial implementation of the statistical model-based iterative reconstruction (MBIR) algorithm, instead of the conventional filtered back projection (FBP) algorithm, has enabled considerable radiation dose reduction in many other clinical applications of MDCT. The purpose of this work was to study the impact of radiation dose and MBIR in the MDCT assessment of airway WT. Methods: An airway phantom was scanned using a clinical MDCT system (Discovery CT750 HD, GE Healthcare) at 4 kV levels and 5 mAs levels. Both FBP and a commercial implementation of MBIR (Veo{sup TM}, GE Healthcare) were used to reconstruct CT images of the airways. For each kV–mAs combination and each reconstruction algorithm, the contrast-to-noise ratio (CNR) of the airways was measured, and the WT of each airway was measured and compared with the nominal value; the relative bias and the angular standard deviation in the measured WT were calculated. For each airway and reconstruction algorithm, the overall performance of WT quantification across all of the 20 kV–mAs combinations was quantified by the sum of squares (SSQs) of the difference between the measured and nominal WT values. Finally, the particular kV–mAs combination and reconstruction algorithm that minimized radiation dose while still achieving a reference WT quantification accuracy level was chosen as the optimal acquisition and reconstruction settings. Results: The wall thicknesses of seven airways of different sizes were analyzed in the study. Compared with FBP, MBIR improved the CNR of the airways, particularly at low radiation dose

  1. Shading correction for on-board cone-beam CT in radiation therapy using planning MDCT images

    SciTech Connect

    Niu Tianye; Sun, Mingshan; Star-Lack, Josh; Gao Hewei; Fan Qiyong; Zhu Lei

    2010-10-15

    Purpose: Applications of cone-beam CT (CBCT) to image-guided radiation therapy (IGRT) are hampered by shading artifacts in the reconstructed images. These artifacts are mainly due to scatter contamination in the projections but also can result from uncorrected beam hardening effects as well as nonlinearities in responses of the amorphous silicon flat panel detectors. While currently, CBCT is mainly used to provide patient geometry information for treatment setup, more demanding applications requiring high-quality CBCT images are under investigation. To tackle these challenges, many CBCT correction algorithms have been proposed; yet, a standard approach still remains unclear. In this work, we propose a shading correction method for CBCT that addresses artifacts from low-frequency projection errors. The method is consistent with the current workflow of radiation therapy. Methods: With much smaller inherent scatter signals and more accurate detectors, diagnostic multidetector CT (MDCT) provides high quality CT images that are routinely used for radiation treatment planning. Using the MDCT image as ''free'' prior information, we first estimate the primary projections in the CBCT scan via forward projection of the spatially registered MDCT data. Since most of the CBCT shading artifacts stem from low-frequency errors in the projections such as scatter, these errors can be accurately estimated by low-pass filtering the difference between the estimated and raw CBCT projections. The error estimates are then subtracted from the raw CBCT projections. Our method is distinct from other published correction methods that use the MDCT image as a prior because it is projection-based and uses limited patient anatomical information from the MDCT image. The merit of CBCT-based treatment monitoring is therefore retained. Results: The proposed method is evaluated using two phantom studies on tabletop systems. On the Catphan(c)600 phantom, our approach reduces the reconstruction error

  2. Comparison of MDCT protocols in trauma patients with suspected splenic injury: superior results with protocol that includes arterial and portal venous phase imaging

    PubMed Central

    Melikian, Raymond; Goldberg, Stephanie; Strife, Brian James; Halvorsen, Robert A.

    2016-01-01

    PURPOSE We aimed to determine which intravenous contrast-enhanced multidetector computed tomography (MDCT) protocol produced the most accurate results for the detection of splenic vascular injury in hemodynamically stable patients who had sustained blunt abdominal trauma. METHODS We retrospectively reviewed 88 patients from 2003 to 2011 who sustained blunt splenic trauma and underwent contrast-enhanced MDCT and subsequent angiography. Results of MDCT scans utilizing single phase (portal venous only, n=8), dual phase (arterial + portal venous or portal venous + delayed, n=42), or triple phase (arterial + portal venous + delayed, n=38) were compared with results of subsequent splenic angiograms for the detection of splenic vascular injury. RESULTS Dual phase imaging was more sensitive and accurate than single phase imaging (P = 0.016 and P = 0.029, respectively). When the subsets of dual phase imaging were compared, arterial + portal venous phase imaging was more sensitive and accurate than portal venous + delayed phase imaging (P = 0.005 and P = 0.002, respectively). Triple phase imaging was more accurate (P = 0.015) than dual phase; however, when compared with the dual phase subset of arterial + portal venous, there was no statistical difference in either sensitivity or accuracy. CONCLUSION Our results support the use of dual phase contrast-enhanced MDCT, which includes the arterial phase, in patients with suspected splenic injury and question the utility of obtaining a delayed sequence. PMID:27334296

  3. Coronary calcium mass scores measured by identical 64-slice MDCT scanners are comparable: a cardiac phantom study.

    PubMed

    Dijkstra, Hildebrand; Greuter, Marcel J W; Groen, Jaap M; Vliegenthart-Proença, Rozemarijn; Renema, Klaasjan W K; de Lange, Frank; Oudkerk, Matthijs

    2010-01-01

    To assess whether absolute mass scores are comparable or differ between identical 64-slice MDCT scanners of the same manufacturer and to compare absolute mass scores to the physical mass and between scan modes using a calcified phantom. A non-moving anthropomorphic phantom with nine calcifications of three sizes and three densities was scanned 30 times on three 64-slice MDCT scanners of manufacturer A and on three 64-slice MDCT scanners of manufacturer B in both sequential and spiral scan mode. The mean mass scores and mass score variabilities of seven calcifications were determined for all scanners; two non-detectable calcifications were omitted. It was analyzed whether identical scanners yielded similar or significantly different mass scores. Furthermore mass scores were compared to the physical mass and mass scores were compared between scan modes. The mass score calibration factor was determined for all scanners. Mass scores obtained on identical scanners were similar for almost all calcifications. Overall, mass score differences between the scanners were small ranging from 1.5 to 3.4% for the total mass scores, and most differences between scanners were observed for high density calcifications. Mass scores were significantly different from the physical mass for almost all calcifications and all scanners. In sequential mode the total physical mass (167.8 mg) was significantly overestimated (+2.3%) for 4 out of 6 scanners. In spiral mode a significant overestimation (+2.5%) was found for system B and a significant underestimation (-1.8%) for two scanners of system A. Mass scores were dependent on the scan mode, for manufacturer A scores were higher in sequential mode and for manufacturer B in spiral mode. For system A using spiral scan mode no differences were found between identical scanners, whereas a few differences were found using sequential mode. For system B the scan mode did not affect the number of different mass scores between identical scanners. Mass

  4. 3D Reconstruction of Phalangeal and Metacarpal Bones of Male Judo Players and Sedentary Men by MDCT Images

    PubMed Central

    Kalayci, Ibrahim

    2008-01-01

    This study has been performed to reveal hand bone peculiarities of elite male judoists by comparing their phalangeal and metacarpal bones with those of sedentary men on the basis of biometric ratio of the bones by means of three-dimensional (3D) reconstruction of multidetector computed tomography (MDCT) images. For this purpose, the axial images of the right and left hands of 8 elite male judo players (mean age: 22.0 ± 2.9 years, mean weight: 64.0 ± 4.9 kg) and 8 sedentary men (mean age: 26.0 ± 2.8 years, mean weight: 69.0 ± 3.6 kg) were obtained from MDCT. After semi-automatic segmentation and manual editing, the tracings of bone surfaces were stacked and overlaid to be reconstructed as the 3D images by the 3D program. All biometrical measurements of the reconstructed images of the bones were automatically calculated by this program to analyze statistically. This study showed that the differences between biometric ratios of judoist and sedentary men’s hand bones were significant contrary to null hypothesis which was established as there is no difference between biometric hand bone ratios of these men of both groups. Therefore null hypothesis was rejected. Author suggests that intense clutching actions practised in judo sports can most probably lead to some hand bone proliferations. 3D reconstructed results belonging to the judo players and sedentary men help orthopaedists to diagnose pathological formations related to hand bones of judoists and may be used for anatomical education in medicine faculties, respectively. We hope that the results from the biometric and reconstructive techniques carried out in this work will contribute to the present knowledge on judoist and shed light on the future studies on sports medicine related to skeletal structure of other sportsmen. Key pointsImage processing of hands of sedentary man and male judo players.3D models of hands of those men by using MDCT images.The results from those models compared in terms of volume

  5. Computed tomography arthrography with traction in the human hip for three-dimensional reconstruction of cartilage and the acetabular labrum

    PubMed Central

    Henak, C.R.; Abraham, C.L.; Peters, C.L.; Sanders, R.K.; Weiss, J.A.; Anderson, A.E.

    2014-01-01

    AIM To develop and demonstrate the efficacy of a computed tomography arthrography (CTA) protocol for the hip that enables accurate three-dimensional reconstructions of cartilage and excellent visualization of the acetabular labrum. MATERIALS AND METHODS Ninety-three subjects were imaged (104 scans); 68 subjects with abnormal anatomy, 11 patients after periacetabular osteotomy surgery, and 25 subjects with normal anatomy. Fifteen to 25 ml of contrast agent diluted with lidocaine was injected using a lateral oblique approach. A Hare traction splint applied traction during CT. The association between traction force and intra-articular joint space was assessed qualitatively under fluoroscopy. Cartilage geometry was reconstructed from the CTA images for 30 subjects; the maximum joint space under traction was measured. RESULTS Using the Hare traction splint, the intra-articular space and boundaries of cartilage could be clearly delineated throughout the joint; the acetabular labrum was also visible. Dysplastic hips required less traction (~5 kg) than normal and retroverted hips required (>10 kg) to separate the cartilage. An increase in traction force produced a corresponding widening of the intra-articular joint space. Under traction, the maximum width of the intra-articular joint space during CT ranged from 0.98–6.7 mm (2.46 ± 1.16 mm). CONCLUSIONS When applied to subjects with normal and abnormal hip anatomy, the CTA protocol presented yields clear delineation of the cartilage and the acetabular labrum. Use of a Hare traction splint provides a simple, cost-effective method to widen the intra-articular joint space during CT, and provides flexibility to vary the traction as required. PMID:25070373

  6. Correlating MDCT Liver Injury Grade and Clinical Outcome in Patients Without Significant Extra-hepatic Injury.

    PubMed

    Kumar, Ravi; Kumar, Atin; Baliyan, Vinit; Gamanagatti, Shivanand; Bhalla, Ashu Seith; Sharma, Raju; Gupta, Amit; Kumar, Subodh; Misra, M C

    2016-08-01

    The aim of the study was to correlate multi-detector computed tomography (MDCT) grading with clinical severity and outcome in liver trauma patients without significant extrahepatic injury. Over a period of 2 years (2011-2013), all patients showing evidence of liver injury on contrast-enhanced CT (CECT) abdomen and without significant extrahepatic trauma were prospectively included in the study. Correlation between the CT injury grade and outcome in terms of mortality, duration of ICU/hospital stay, fluid and blood requirements, need for intervention and complications were assessed. The significance of the difference in mortality, duration of ICU/hospital stay, fluid requirement and blood requirements among the patients with various injury grades was assessed by Kruskal-Wallis test. The significance of the difference in need for intervention and complications among the patients with various injury grades was assessed by Fisher's exact test. A total of 198 patients were found to have evidence of hepatic injury on CECT. Out of 198 patients, 117 had insignificant extrahepatic trauma. The overall mean age for these 117 patients was 25.74 ± 15.53 (age range 2-84 years). Death rates according to AAST grades were 0 % in grades II and III, 6.89 % in grade IV and 9.09 % in grade V (p = 0.053). The mean ICU and total hospital stay for grade II was 1.32 and 5.91 days, for grade III was 1.76 and 8.48, for grade IV was 2.86 and 10.31 days and for grade V was 6.54 and 12 days, respectively (p = 0.0001 for ICU, p = 0.0003 for total stay). Mean input and fluid deficit according to various grades were 8634/2607 ml for grade II, 9535/2555 ml for grade III, 15,549/6242 ml for grade IV and 19,958/8280 ml for grade V (p value input-0.0016, output-input (fluid deficit)-0.0001). Average unit of RBC and sum of the blood products transfused were 1.73 and 2.26 for grade II, 2.18 and 2.72 for grade III, 3.03 and 6.27 for grade IV, 6.85 and 38.12 for grade V

  7. Radiological surveillance of formerly asbestos-exposed power industry workers: rates and risk factors of benign changes on chest X-ray and MDCT

    PubMed Central

    2014-01-01

    Background To determine the prevalence of asbestos-related changes on chest X-ray (CXR) and low-dose multidetector-row CT (MDCT) of the thorax in a cohort of formerly asbestos-exposed power industry workers and to assess the importance of common risk factors associated with specific radiological changes. Methods To assess the influence of selected risk factors (age, time since first exposure, exposure duration, cumulative exposure and pack years) on typical asbestos-related radiographic changes, we employed multiple logistic regression and receiver operating characteristic (ROC) analysis. Results On CXR, pleural changes and asbestosis were strongly associated with age, years since first exposure and exposure duration. The MDCT results showed an association between asbestosis and age and between plaques and exposure duration, years since first exposure and cumulative exposure. Parenchymal changes on CXR and MDCT, and diffuse pleural thickening on CXR were both associated with smoking. Using a cut-off of 55 years for age, 17 years for exposure duration and 28 years for latency, benign radiological changes in the cohort with CXR could be predicted with a sensitivity of 82.0% for all of the three variables and a specificity of 47.4%, 39.0% and 40.6%, respectively. Conclusions Participants aged 55 years and older and those with an asbestos exposure of at least 17 years or 28 years since first exposure should be seen as having an increased risk of abnormal radiological findings. For implementing a more focused approach the routine use of low-dose MDCT rather than CXR at least for initial examinations would be justified. PMID:24808921

  8. Pulmonary 64-MDCT angiography with 50 mL of iodinated contrast material in an unselected patient population: a feasible protocol*

    PubMed Central

    Trad, Henrique Simão; Boasquevisque, Gustavo Santos; Giacometti, Tiago Rangon; Trad, Catherine Yang; Zoghbi Neto, Orlando Salomão; Trad, Clovis Simão

    2016-01-01

    Objective To propose a protocol for pulmonary angiography using 64-slice multidetector computed tomography (64-MDCT) with 50 mL of iodinated contrast material, in an unselected patient population, as well as to evaluate vascular enhancement and image quality. Materials and Methods We evaluated 29 patients (22-86 years of age). The body mass index ranged from 19.0 kg/m2 to 41.8 kg/m2. Patients underwent pulmonary CT angiography in a 64-MDCT scanner, receiving 50 mL of iodinated contrast material via venous access at a rate of 4.5 mL/s. Bolus tracking was applied in the superior vena cava. Two experienced radiologists assessed image quality and vascular enhancement. Results The mean density was 382 Hounsfield units (HU) for the pulmonary trunk; 379 and 377 HU for the right and left main pulmonary arteries, respectively; and 346 and 364 HU for the right and left inferior pulmonary arteries, respectively. In all patients, subsegmental arteries were analyzed. There were streak artifacts from contrast material in the superior vena cava in all patients. However, those artifacts did not impair the image analysis. Conclusion Our findings suggest that pulmonary angiography using 64-MDCT with 50 mL of iodinated contrast can produce high quality images in unselected patient populations. PMID:27141128

  9. Systems for Lung Volume Standardization during Static and Dynamic MDCT-based Quantitative Assessment of Pulmonary Structure and Function

    PubMed Central

    Fuld, Matthew K.; Grout, Randall; Guo, Junfeng; Morgan, John H.; Hoffman, Eric A.

    2013-01-01

    Rationale and Objectives Multidetector-row Computed Tomography (MDCT) has emerged as a tool for quantitative assessment of parenchymal destruction, air trapping (density metrics) and airway remodeling (metrics relating airway wall and lumen geometry) in chronic obstructive pulmonary disease (COPD) and asthma. Critical to the accuracy and interpretability of these MDCT-derived metrics is the assurance that the lungs are scanned during a breath-hold at a standardized volume. Materials and Methods A computer monitored turbine-based flow meter system was developed to control patient breath-holds and facilitate static imaging at fixed percentages of the vital capacity. Due to calibration challenges with gas density changes during multi-breath xenon-CT an alternative system was required. The design incorporated dual rolling seal pistons. Both systems were tested in a laboratory environment and human subject trials. Results The turbine-based system successfully controlled lung volumes in 32/37 subjects, having a linear relationship for CT measured air volume between repeated scans: for all scans, the mean and confidence interval of the differences (scan1-scan2) was −9 ml (−169, 151); for TLC alone 6 ml (−164, 177); for FRC alone, −23 ml (−172, 126). The dual-piston system successfully controlled lung volume in 31/41 subjects. Study failures related largely to subject non-compliance with verbal instruction and gas leaks around the mouthpiece. Conclusion We demonstrate the successful use of a turbine-based system for static lung volume control and demonstrate its inadequacies for dynamic xenon-CT studies. Implementation of a dual-rolling seal spirometer has been shown to adequately control lung volume for multi-breath wash-in xenon-CT studies. These systems coupled with proper patient coaching provide the tools for the use of CT to quantitate regional lung structure and function. The wash-in xenon-CT method for assessing regional lung function, while not

  10. Development of a voxel-matching technique for substantial reduction of subtraction artifacts in temporal subtraction images obtained from thoracic MDCT.

    PubMed

    Itai, Yoshinori; Kim, Hyoungseop; Ishikawa, Seiji; Katsuragawa, Shigehiko; Doi, Kunio

    2010-02-01

    A temporal subtraction image, which is obtained by subtraction of a previous image from a current one, can be used for enhancing interval changes (such as formation of new lesions and changes in existing abnormalities) on medical images by removing most of the normal structures. However, subtraction artifacts are commonly included in temporal subtraction images obtained from thoracic computed tomography and thus tend to reduce its effectiveness in the detection of pulmonary nodules. In this study, we developed a new method for substantially removing the artifacts on temporal subtraction images of lungs obtained from multiple-detector computed tomography (MDCT) by using a voxel-matching technique. Our new method was examined on 20 clinical cases with MDCT images. With this technique, the voxel value in a warped (or nonwarped) previous image is replaced by a voxel value within a kernel, such as a small cube centered at a given location, which would be closest (identical or nearly equal) to the voxel value in the corresponding location in the current image. With the voxel-matching technique, the correspondence not only between the structures but also between the voxel values in the current and the previous images is determined. To evaluate the usefulness of the voxel-matching technique for removal of subtraction artifacts, the magnitude of artifacts remaining in the temporal subtraction images was examined by use of the full width at half maximum and the sum of a histogram of voxel values, which may indicate the average contrast and the total amount, respectively, of subtraction artifacts. With our new method, subtraction artifacts due to normal structures such as blood vessels were substantially removed on temporal subtraction images. This computerized method can enhance lung nodules on chest MDCT images without disturbing misregistration artifacts.

  11. Unenhanced MDCT in Suspected Urolithiasis: Improved Stone Detection and Density Measurements Using Coronal Maximum-Intensity-Projection Images

    PubMed Central

    Corwin, Michael T.; Hsu, Margaret; McGahan, John P.; Wilson, Machelle; Lamba, Ramit

    2016-01-01

    OBJECTIVE The purpose of this study was to determine whether coronal maximum-intensity-projection (MIP) reformations improve urinary tract stone detection and density measurements compared with routine axial and coronal images. MATERIALS AND METHODS Forty-five consecutive patients who underwent MDCT for suspected urolithiasis were included. Two radiologists independently determined the number of stones on 5-, 3-, and 1.25-mm axial, 5- and 3-mm coronal, and 5-mm coronal MIP images. The reference standard was obtained by consensus review using all six datasets. Stone density was determined for all calculi 4 mm or larger on all datasets. RESULTS There were a total of 115 stones. Reader 1 identified 111 (96.5%), 112 (97.4%), 97 (84.3%), 102 (88.7%), 99 (86.1%), and 85 (73.9%) stones and reader 2 identified 105 (91.3%), 102 (88.7%), 85 (73.9%), 89 (77.4%), 89 (77.4%), and 76 (66.1%) stones on the MIP, 1.25-mm axial, 3-mm axial, 3-mm coronal, 5-mm coronal, and 5-mm axial images, respectively. Both readers identified more stones on the MIP images than on the 3- or 5-mm axial or coronal images (p < 0.0001). The mean difference in stone attenuation compared with the thin axial images was significantly less for the MIP images (44.6 HU) compared with 3-mm axial (235 HU), 3-mm coronal (309 HU), and 5-mm coronal (329.6 HU) or axial images (347.8 HU) (p < 0.0001). CONCLUSION Coronal MIP reformations allow more accurate identification and density measurements of urinary tract stones compared with routine axial and coronal reformations. PMID:24147474

  12. Monte Carlo simulations in multi-detector CT (MDCT) for two PET/CT scanner models using MASH and FASH adult phantoms

    NASA Astrophysics Data System (ADS)

    Belinato, W.; Santos, W. S.; Paschoal, C. M. M.; Souza, D. N.

    2015-06-01

    The combination of positron emission tomography (PET) and computed tomography (CT) has been extensively used in oncology for diagnosis and staging of tumors, radiotherapy planning and follow-up of patients with cancer, as well as in cardiology and neurology. This study determines by the Monte Carlo method the internal organ dose deposition for computational phantoms created by multidetector CT (MDCT) beams of two PET/CT devices operating with different parameters. The different MDCT beam parameters were largely related to the total filtration that provides a beam energetic change inside the gantry. This parameter was determined experimentally with the Accu-Gold Radcal measurement system. The experimental values of the total filtration were included in the simulations of two MCNPX code scenarios. The absorbed organ doses obtained in MASH and FASH phantoms indicate that bowtie filter geometry and the energy of the X-ray beam have significant influence on the results, although this influence can be compensated by adjusting other variables such as the tube current-time product (mAs) and pitch during PET/CT procedures.

  13. Comparison of sensitivity and reading time for the use of computer-aided detection (CAD) of pulmonary nodules at MDCT as concurrent or second reader.

    PubMed

    Beyer, F; Zierott, L; Fallenberg, E M; Juergens, K U; Stoeckel, J; Heindel, W; Wormanns, D

    2007-11-01

    The purpose of this study was to compare sensitivity for detection of pulmonary nodules in MDCT scans and reading time of radiologists when using CAD as the second reader (SR) respectively concurrent reader (CR). Four radiologists analyzed 50 chest MDCT scans chosen from clinical routine two times and marked all detected pulmonary nodules: first with CAD as CR (display of CAD results immediately in the reading session) and later (median 14 weeks) with CAD as SR (display of CAD markers after completion of first reading without CAD). A Siemens LungCAD prototype was used. Sensitivities for detection of nodules and reading times were recorded. Sensitivity of reading with CAD as SR was significantly higher than reading without CAD (p < 0.001) and CAD as CR (p < 0.001). For nodule size of 1.75 mm or above no significant sensitivity difference between CAD as CR and reading without CAD was observed; e.g., for nodules above 4 mm sensitivity was 68% without CAD, 68% with CAD as CR (p = 0.45) and 75% with CAD as SR (p < 0.001). Reading time was significantly shorter for CR (274 s) compared to reading without CAD (294 s; p = 0.04) and SR (337 s; p < 0.001). In our study CAD could either speed up reading of chest CT cases for pulmonary nodules without relevant loss of sensitivity when used as CR, or it increased sensitivity at the cost of longer reading times when used as SR.

  14. Celiac Axis, Common Hepatic and Hepatic Artery Variants as Evidenced on MDCT Angiography in South Indian Population

    PubMed Central

    Parthasarathy, Ramesh

    2016-01-01

    Introduction With the increase in the hepatobiliary, pancreatic surgeries and liver transplantation, being aware of the anatomic variations of the celiac axis and the hepatic arteries is of paramount importance. Aim To illustrate the normal anatomy and variants of the celiac axis and the hepatic arteries with multidetector computed tomographic (MDCT) angiography in South Indian population and determine the potential variations in the celiac axis anatomy and the hepatic arteries, thus assisting the hepatobiliary surgeon and the interventional radiologist in avoiding iatrogenic injury to the arteries. Materials and Methods Two hundred patients undergoing abdominal CT angiography from July 2014 till July 2015 were retrospectively studied for hepatic arterial and celiac axis anatomical variation. The anatomic variations in our study were correlated with other studies. Results The celiac axis (CA) and the hepatic artery (HA) variations were analysed as per criteria laid by Song et al., and Michel. Out of 15 possible CA variations, 5 types of celiac artery variations were seen in 14 patients. A normal CA was seen in 179(89.5%) patients of the 200 patients. In the remaining 7 patients, the CA anatomy was classified as ambiguous since there was separate origin of the right and left hepatic arteries from the CA with absent common hepatic artery (CHA). The CHA originated normally from the celiac axis in 94% of the cases. Variation of CHA origin was seen in 5 patients. Normal HA anatomy was seen in 114 (57%) patients. Variation in HA anatomy was seen in 86 (43%) patients. Origin of the right hepatic artery (RHA) from the hepatic artery proper was seen in 182 (91%) patients and replaced origin of RHA from the superior mesenteric artery (SMA) was seen in 18 (9%) of the cases. Accessory RHA was seen in 7(3.5%) patients. The left hepatic artery (LHA) originated from the hepatic artery proper in 186 (93%) patients and replaced origin of LHA from the left gastric artery (LGA) was

  15. Unusual vanishing interstitial lymphatic "pearls" in a patient presenting with extensive interstitial and mediastinal MDCT features of acute cardiogenic failure related to bradycardia and mitral regurgitation.

    PubMed

    Coulier, Bruno; El Khoury, Elie; Deprez, Fabrice C; Ghaye, Benoît; Van den Broeck, Stephane; Tourmous, Hussein

    2014-12-01

    Thoracic multidetector computed tomography-MDCT-was simultaneously performed during emergency abdominal CT in a patient presenting with abdominal pain and acute cardiogenic edema related to sick sinus syndrome and mitral prolapse with regurgitation. A constellation of severe but completely reversible interstitial and mediastinal features was found comprising pleural effusions, diffuse alveolar ground glass, thickening of the bronchial walls and septal lines, hazy infiltration of the mediastinal fat, and enlarged lymphatic nodes. Multiple atypical hypodense nodular "pearls" were also found. These oval shape or fusiform pearls were distributed along the thickened septal lines and disappeared completely after treatment. The hypothesis of transient lymphatic ectasia or lakes is proposed for these never previously described abnormalities.

  16. Hepatic Arterial Configuration in Relation to the Segmental Anatomy of the Liver; Observations on MDCT and DSA Relevant to Radioembolization Treatment

    SciTech Connect

    Hoven, Andor F. van den Leeuwen, Maarten S. van Lam, Marnix G. E. H. Bosch, Maurice A. A. J. van den

    2015-02-15

    PurposeCurrent anatomical classifications do not include all variants relevant for radioembolization (RE). The purpose of this study was to assess the individual hepatic arterial configuration and segmental vascularization pattern and to develop an individualized RE treatment strategy based on an extended classification.MethodsThe hepatic vascular anatomy was assessed on MDCT and DSA in patients who received a workup for RE between February 2009 and November 2012. Reconstructed MDCT studies were assessed to determine the hepatic arterial configuration (origin of every hepatic arterial branch, branching pattern and anatomical course) and the hepatic segmental vascularization territory of all branches. Aberrant hepatic arteries were defined as hepatic arterial branches that did not originate from the celiac axis/CHA/PHA. Early branching patterns were defined as hepatic arterial branches originating from the celiac axis/CHA.ResultsThe hepatic arterial configuration and segmental vascularization pattern could be assessed in 110 of 133 patients. In 59 patients (54 %), no aberrant hepatic arteries or early branching was observed. Fourteen patients without aberrant hepatic arteries (13 %) had an early branching pattern. In the 37 patients (34 %) with aberrant hepatic arteries, five also had an early branching pattern. Sixteen different hepatic arterial segmental vascularization patterns were identified and described, differing by the presence of aberrant hepatic arteries, their respective vascular territory, and origin of the artery vascularizing segment four.ConclusionsThe hepatic arterial configuration and segmental vascularization pattern show marked individual variability beyond well-known classifications of anatomical variants. We developed an individualized RE treatment strategy based on an extended anatomical classification.

  17. Influence of body habitus and use of oral contrast on reader confidence in patients with suspected acute appendicitis using 64 MDCT.

    PubMed

    Anderson, Stephan W; Rhea, James T; Milch, Holly N; Ozonoff, Al; Lucey, Brian C; Soto, Jorge A

    2010-11-01

    The purpose of this study is to evaluate how body habitus affects reader confidence in diagnosing acute appendicitis and appendiceal visualization using 64 MDCT technology with and without oral contrast. We conducted a HIPAA compliant, IRB approved study of adult patients presenting to the Emergency Department with nontraumatic abdominal pain. Subjects were randomized to two groups: 64 MDCT scans performed with oral and intravenous contrast or scans performed solely with intravenous contrast. Three radiologists established their confidence about the presence of appendicitis as well as recording whether the appendix was visualized. Reader confidence in diagnosing acute appendicitis was compared between the two groups for the three readers. The impact of patient BMI and estimated intra-abdominal fat on reader confidence in diagnosing appendicitis was determined. Finally, a comparison of the effect of BMI and intra-abdominal fat on appendiceal visualization between the two groups was carried out. Three hundred three patients were enrolled in this study. There was a statistically significant difference in confidence based on BMI for reader 2, group 1 in diagnosing appendicitis. No further statistically significant differences in reader confidence for diagnosing appendicitis based on BMI or intra-abdominal fat were identified. There was no influence of BMI or intra-abdominal fat on appendiceal visualization. Increasing BMI was seen to improve reader confidence for one of three readers in patients that received both oral and intravenous contrast. No further effects of BMI or intra-abdominal fat on confidence in diagnosing or excluding appendicitis were seen. Neither BMI nor intra-abdominal fat were seen to influence appendiceal visualization.

  18. Reducing radiation dose to selected organs by selecting the tube start angle in MDCT helical scans: A Monte Carlo based study

    SciTech Connect

    Zhang Di; Zankl, Maria; DeMarco, John J.; Cagnon, Chris H.; Angel, Erin; Turner, Adam C.; McNitt-Gray, Michael F.

    2009-12-15

    Purpose: Previous work has demonstrated that there are significant dose variations with a sinusoidal pattern on the peripheral of a CTDI 32 cm phantom or on the surface of an anthropomorphic phantom when helical CT scanning is performed, resulting in the creation of ''hot'' spots or ''cold'' spots. The purpose of this work was to perform preliminary investigations into the feasibility of exploiting these variations to reduce dose to selected radiosensitive organs solely by varying the tube start angle in CT scans. Methods: Radiation dose to several radiosensitive organs (including breasts, thyroid, uterus, gonads, and eye lenses) resulting from MDCT scans were estimated using Monte Carlo simulation methods on voxelized patient models, including GSF's Baby, Child, and Irene. Dose to fetus was also estimated using four pregnant female models based on CT images of the pregnant patients. Whole-body scans were simulated using 120 kVp, 300 mAs, both 28.8 and 40 mm nominal collimations, and pitch values of 1.5, 1.0, and 0.75 under a wide range of start angles (0 deg. - 340 deg. in 20 deg. increments). The relationship between tube start angle and organ dose was examined for each organ, and the potential dose reduction was calculated. Results: Some organs exhibit a strong dose variation, depending on the tube start angle. For small peripheral organs (e.g., the eye lenses of the Baby phantom at pitch 1.5 with 40 mm collimation), the minimum dose can be 41% lower than the maximum dose, depending on the tube start angle. In general, larger dose reductions occur for smaller peripheral organs in smaller patients when wider collimation is used. Pitch 1.5 and pitch 0.75 have different mechanisms of dose reduction. For pitch 1.5 scans, the dose is usually lowest when the tube start angle is such that the x-ray tube is posterior to the patient when it passes the longitudinal location of the organ. For pitch 0.75 scans, the dose is lowest when the tube start angle is such that the x

  19. The development, validation and application of a multi-detector CT (MDCT) scanner model for assessing organ doses to the pregnant patient and the fetus using Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Gu, J.; Bednarz, B.; Caracappa, P. F.; Xu, X. G.

    2009-05-01

    The latest multiple-detector technologies have further increased the popularity of x-ray CT as a diagnostic imaging modality. There is a continuing need to assess the potential radiation risk associated with such rapidly evolving multi-detector CT (MDCT) modalities and scanning protocols. This need can be met by the use of CT source models that are integrated with patient computational phantoms for organ dose calculations. Based on this purpose, this work developed and validated an MDCT scanner using the Monte Carlo method, and meanwhile the pregnant patient phantoms were integrated into the MDCT scanner model for assessment of the dose to the fetus as well as doses to the organs or tissues of the pregnant patient phantom. A Monte Carlo code, MCNPX, was used to simulate the x-ray source including the energy spectrum, filter and scan trajectory. Detailed CT scanner components were specified using an iterative trial-and-error procedure for a GE LightSpeed CT scanner. The scanner model was validated by comparing simulated results against measured CTDI values and dose profiles reported in the literature. The source movement along the helical trajectory was simulated using the pitch of 0.9375 and 1.375, respectively. The validated scanner model was then integrated with phantoms of a pregnant patient in three different gestational periods to calculate organ doses. It was found that the dose to the fetus of the 3 month pregnant patient phantom was 0.13 mGy/100 mAs and 0.57 mGy/100 mAs from the chest and kidney scan, respectively. For the chest scan of the 6 month patient phantom and the 9 month patient phantom, the fetal doses were 0.21 mGy/100 mAs and 0.26 mGy/100 mAs, respectively. The paper also discusses how these fetal dose values can be used to evaluate imaging procedures and to assess risk using recommendations of the report from AAPM Task Group 36. This work demonstrates the ability of modeling and validating an MDCT scanner by the Monte Carlo method, as well as

  20. Comparison of sensitivity and reading time for the use of computer aided detection (CAD) of pulmonary nodules at MDCT as concurrent or second reader

    NASA Astrophysics Data System (ADS)

    Beyer, F.; Zierott, L.; Fallenberg, E. M.; Juergens, K.; Stoeckel, J.; Heindel, W.; Wormanns, D.

    2006-03-01

    Purpose: To compare sensitivity and reading time when using CAD as second reader resp. concurrent reader. Materials and Methods: Fifty chest MDCT scans due to clinical indication were analysed independently by four radiologists two times: First with CAD as concurrent reader (display of CAD results simultaneously to the primary reading by the radiologist); then after a median of 14 weeks with CAD as second reader (CAD results were shown after completion of a reading session without CAD). A prototype version of Siemens LungCAD (Siemens,Malvern,USA) was used. Sensitivities and reading times for detecting nodules >=4mm of concurrent reading, reading without CAD and second reading were recorded. In a consensus conference false positive findings were eliminated. Student's T-Test was used to compare sensitivities and reading times. Results: 108 true positive nodules were found. Mean sensitivity was .68 for reading without CAD, .68 for concurrent reading and .75 for second reading. Differences of sensitivities were significant between concurrent and second reading (p<.001) resp. reading without CAD and second reading (p=.001). Mean reading time for concurrent reading was significant shorter (274s) compared to reading without CAD (294s;p=.04) and second reading (337sp<.001). New work to be presented: To our knowledge this is the first study that compares sensitivities and reading times between use of CAD as concurrent resp. second reader. Conclusion: CAD can either be used to speed up reading of chest CT cases for pulmonary nodules without loss of sensitivity as concurrent reader -OR (and not AND) to increase sensitivity and reading time as second reader.

  1. Congenital Anomalies of the Aortic Arch: Evaluation with the Use of Multidetector Computed Tomography

    PubMed Central

    Büyükbayraktar, Fatma Gül; Ölçer, Tülay; Cumhur, Turhan

    2009-01-01

    Congenital anomalies of the aortic arch have clinical importance, as the anomalies may be associated with vascular rings or other congenital cardiovascular diseases. Multidetector computed tomography (MDCT) angiography enables one to display the detailed anatomy of vascular structures and the spatial relationships with adjacent organs; this ability is the greatest advantage of the use of MDCT angiography in comparison to other imaging modalities in the evaluation of the congenital anomalies of the aortic arch. In this review article, we illustrate 16-slice MDCT angiography appearances of congenital anomalies of the aortic arch. PMID:19270864

  2. Radiofrequency Ablation of Liver Metastases-Software-Assisted Evaluation of the Ablation Zone in MDCT: Tumor-Free Follow-Up Versus Local Recurrent Disease

    SciTech Connect

    Keil, Sebastian Bruners, Philipp; Schiffl, Katharina; Sedlmair, Martin; Muehlenbruch, Georg; Guenther, Rolf W.; Das, Marco; Mahnken, Andreas H.

    2010-04-15

    The purpose of this study was to investigate differences in change of size and CT value between local recurrences and tumor-free areas after CT-guided radiofrequency ablation (RFA) of hepatic metastases during follow-up by means of dedicated software for automatic evaluation of hepatic lesions. Thirty-two patients with 54 liver metastases from breast or colorectal cancer underwent triphasic contrast-enhanced multidetector-row computed tomography (MDCT) to evaluate hepatic metastatic spread and localization before CT-guided RFA and for follow-up after intervention. Sixteen of these patients (65.1 {+-} 10.3 years) with 30 metastases stayed tumor-free (group 1), while the other group (n = 16 with 24 metastases; 62.0 {+-} 13.8 years) suffered from local recurrent disease (group 2). Applying an automated software tool (SyngoCT Oncology; Siemens Healthcare, Forchheim, Germany), size parameters (volume, RECIST, WHO) and attenuation were measured within the lesions before, 1 day after, and 28 days after RFA treatment. The natural logarithm (ln) of the quotient of the volume 1 day versus 28 days after RFA treament was computed: lnQ1//28/0{sub volume}. Analogously, ln ratios of RECIST, WHO, and attenuation were computed and statistically evaluated by repeated-measures ANOVA. One lesion in group 2 was excluded from further evaluation due to automated missegmentation. Statistically significant differences between the two groups were observed with respect to initial volume, RECIST, and WHO (p < 0.05). Furthermore, ln ratios corresponding to volume, RECIST, and WHO differed significantly between the two groups. Attenuation evaluations showed no significant differences, but there was a trend toward attenuation assessment for the parameter lnQ28/0{sub attenuation} (p = 0.0527), showing higher values for group 1 (-0.4 {+-} 0.3) compared to group 2 (-0.2 {+-} 0.2). In conclusion, hepatic metastases and their zone of coagulation necrosis after RFA differed significantly between tumor

  3. Multi-Detector Computed Tomography Angiography for Coronary Artery Disease

    PubMed Central

    2005-01-01

    Executive Summary Purpose Computed tomography (CT) scanning continues to be an important modality for the diagnosis of injury and disease, most notably for indications of the head and abdomen. (1) According to a recent report published by the Canadian Institutes of Health Information, (1) there were about 10.3 scanners per million people in Canada as of January 2004. Ontario had the fewest number of CT scanners per million compared to the other provinces (8 CT scanners per million). The wait time for CT in Ontario of 5 weeks approaches the Canadian median of 6 weeks. This health technology and policy appraisal systematically reviews the published literature on multidetector CT (MDCT) angiography as a diagnostic tool for the newest indication for CT, coronary artery disease (CAD), and will apply the results of the review to current health care practices in Ontario. This review does not evaluate MDCT to detect coronary calcification without contrast medium for CAD screening purposes. The Technology Compared with conventional CT scanning, MDCT can provide smaller pieces of information and can cover a larger area faster. (2) Advancing MDCT technology (8, 16, 32, 64 slice systems) is capable of producing more images in less time. For general CT scanning, this faster capability can reduce the time that patients must stay still during the procedure, thereby reducing potential movement artefact. However, the additional clinical utility of images obtained from faster scanners compared to the images obtained from conventional CT scanners for current CT indications (i.e., non-moving body parts) is not known. There are suggestions that the new fast scanners can reduce wait times for general CT. MDCT angiography that utilizes a contrast medium, has been proposed as a minimally invasive replacement to coronary angiography to detect coronary artery disease. MDCT may take between 15 to 45 minutes; coronary angiography may take up to 1 hour. Although 16-slice and 32-slice CT

  4. Forensic considerations for preprocessing effects on clinical MDCT scans.

    PubMed

    Wade, Andrew D; Conlogue, Gerald J

    2013-05-01

    Manipulation of digital photographs destined for medico-legal inquiry must be thoroughly documented and presented with explanation of any manipulations. Unlike digital photography, computed tomography (CT) data must pass through an additional step before viewing. Reconstruction of raw data involves reconstruction algorithms to preprocess the raw information into display data. Preprocessing of raw data, although it occurs at the source, alters the images and must be accounted for in the same way as postprocessing. Repeated CT scans of a gunshot wound phantom were made using the Toshiba Aquilion 64-slice multidetector CT scanner. The appearance of fragments, high-density inclusion artifacts, and soft tissue were assessed. Preprocessing with different algorithms results in substantial differences in image output. It is important to appreciate that preprocessing affects the image, that it does so differently in the presence of high-density inclusions, and that preprocessing algorithms and scanning parameters may be used to overcome the resulting artifacts.

  5. Multidetector computed tomographic angiography of aberrant subclavian arteries.

    PubMed

    Türkvatan, Aysel; Büyükbayraktar, Fatma Gül; Olçer, Tülay; Cumhur, Turhan

    2009-02-01

    The purpose of this study was to evaluate the utility of 16-slice multidetector computed tomographic (MDCT) angiography for identifying anatomic features of aberrant subclavian arteries. Seventeen patients with aberrant subclavian arteries were assessed by MDCT angiography. The aortic arch position, the presence of a Kommerell's diverticulum, aneurysm, vascular compression of trachea and oesophagus and associated cardiovascular abnormalities were evaluated. MDCT findings were confirmed by surgery in eight patients but in the other nine patients no further evaluation or management was warranted as the aberrant subclavian artery had no significant clinical consequence. Eleven patients had an aberrant right subclavian artery arising from the left aortic arch and six patients had an aberrant left subclavian artery arising from the right aortic arch. Kommerell's diverticulum was identified in three patients with an aberrant right subclavian artery and in five patients with an aberrant left subclavian artery. In two patients it was aneurysmal. Oesophageal compression was detected in eight patients, and tracheal compression was identified in only one paediatric patient. An aberrant subclavian artery was associated with complex congenital heart disease in one patient, intracardiac defects in two patients, aortic coarctation in two patients, patent ductus arteriosus in two patients and an aberrant vertebral artery in one patient. In conclusion, MDCT angiography is superior to digital subtraction angiography for the assessment of aberrant subclavian arteries since digital subtraction angiography has only a poor ability to visualize adjacent structures completely and is invasive in nature. MDCT angiography or magnetic resonance angiography are the current standard in the initial evaluation of thoracic vascular anomalies.

  6. Asbestos Surveillance Program Aachen (ASPA): initial results from baseline screening for lung cancer in asbestos-exposed high-risk individuals using low-dose multidetector-row CT.

    PubMed

    Das, Marco; Mühlenbruch, Georg; Mahnken, Andreas H; Hering, K G; Sirbu, H; Zschiesche, W; Knoll, Lars; Felten, Michael K; Kraus, Thomas; Günther, Rolf W; Wildberger, Joachim E

    2007-05-01

    The purpose of this study was to assess the prevalence of lung cancer in a high-risk asbestos-exposed cohort using low-dose MDCT. Of a population of 5,389 former power-plant workers, 316 were characterized as individuals at highest risk for lung cancer according to a lung-cancer risk model including age, asbestos exposure and smoking habits. Of these 316, 187 (mean age: 66.6 years) individuals were included in a prospective trial. Mean asbestos exposure time was 29.65 years and 89% were smokers. Screening was performed on a 16-slice MDCT (Siemens) with low-dose technique (10/20 mAs(eff.); 1 mm/0.5 mm increment). In addition to soft copy PACS reading analysis on a workstation with a dedicated lung analysis software (LungCARE; Siemens) was performed. One strongly suspicious mass and eight cases of histologically proven lung cancer were found plus 491 additional pulmonary nodules (average volume: 40.72 ml, average diameter 4.62 mm). Asbestos-related changes (pleural plaques, fibrosis) were visible in 80 individuals. Lung cancer screening in this high-risk cohort showed a prevalence of lung cancer of 4.28% (8/187) at baseline screening with an additional large number of indeterminate pulmonary nodules. Low-dose MDCT proved to be feasible in this highly selected population.

  7. Scaphotrapezial ligament: normal arthro-CT and arthro-MRI appearance with anatomical and clinical correlation.

    PubMed

    Holveck, A; Wolfram-Gabel, R; Dosch, J C; Sanda, R; Antunes, A B F; Decock, S; Zorn, P; Foessel, L; Bierry, G; Clavert, P; Dietemann, J L; Kahn, J L

    2011-08-01

    The purpose of our study was to demonstrate and describe the MR and arthro-CT anatomic appearance of the scaphotrapezial ligament and illustrate some of the pathologies involving this structure. This ligament consists of two slips that originate from the radiopalmar aspect of the scaphoid tuberosity and extend distally, forming a V shape. The ulnar fibers, which are just radial to the flexor carpi radialis sheath, inserted along the trapezial ridge. The radial fibers were found to be thinner and inserted at the radial aspect of the trapezium. Twelve fresh cadaver wrists were dissected, with close attention paid to the scaphotrapezio-trapezoidal (STT) joint. An osseoligamentous specimen was dissected with removal of all musculotendinous structures around the STT joint and was performed with high-resolution acquisition in a 128-MDCT scanner. Samples of the wrist area were collected from two fetal specimens. A retrospective study of 55 patients with wrist pain that were submitted to arthrography, arthro-CT, and arthro-MRI imaging was performed (10 patients on a 3-T superconducting magnet and 45 patients on a 1.5-T system). Another ten patients had high-resolution images on a 3-T superconducting magnet without arthrographic injection. MR arthrography and arthro-CT improved visualization and provided detailed information about the anatomy of the scaphotrapezial ligament. Knowledge of the appearance of this normal ligament on MRI allows accurate diagnosis of lesions and will aid when surgery is indicated or may have a role in avoiding unnecessary immobilization. PMID:21455837

  8. Negative bone scans of joints after aspiration or arthrography: experimental studies.

    PubMed

    Traughber, P D; Manaster, B J; Murphy, K; Alazraki, N P

    1986-01-01

    It has long been suspected anecdotally that needle aspiration or contrast arthrogram before bone scan may cause a false-positive bone scan. This dictum often directs the sequence of events in the clinical workup of joint disease, yet data to support or refute this are lacking. This study was undertaken to generate such data. Fifty-six joints in mature dogs were examined, including hips, knees, elbows, and shoulders. The joints were examined in pairs; one joint was injected with Conray 60 for an arthrogram, and the contralateral joint was injected with an equal volume of normal saline to simulate a joint aspiration. Confirmation of needle placement and injection into the joints was made with fluoroscopic and digital subtraction imaging. Numbers of attempts required for aspiration and quantity of contrast material extravasated were noted for each joint. Baseline 99mTc-HDP or 99mTc-MDP bone scans were done before the experimental joint aspirations, with follow-up scans at 24 and 96 hr. The scans showed no significant change from baseline after either needle aspiration or arthrogram. When the diagnostic workup suggests the need for such a procedure, it should be performed. In contradiction to popular belief, joint aspiration and/or arthrogram did not affect a subsequent bone scan. PMID:3484417

  9. Inferior joint space arthrography of normal temporomandibular joints: Reassessment of diagnostic criteria

    SciTech Connect

    Kaplan, P.A.; Tu, H.K.; Sleder, P.R.; Lydiatt, D.D.; Laney, T.J.

    1986-06-01

    Inferior joint space arthrograms of the temporomandibular joints of 31 healthy volunteers (62 joints) were obtained to determine normal arthrographic findings. The superior margin of the anterior recess was smooth and flat in 68% of the joints and concave in 32% with the subjects' mouths closed. The concavity was the result of the anterior ridge of the meniscus impinging on the contrast material. The concave impression could be distinguished easily from an anteriorly displaced meniscus on videotaped studies, which demonstrated a smooth transition of contrast material from the anterior to the posterior recess during opening of a subject's mouth. With the mouth open, the anterior recess decreased in size, appearing as a small, crescent-shaped collection of contrast material anterior to the head of the condyle in 52 joints (84%); it remained large in ten joints (16%) at maximal mouth opening. The configuration of the posterior recess was identical to that described previously; however, with the subjects' mouths closed, it was larger than the anterior recess, contrary to most previously reported results.

  10. Semi-automatic segmentation and detection of aorta dissection wall in MDCT angiography.

    PubMed

    Krissian, Karl; Carreira, Jose M; Esclarin, Julio; Maynar, Manuel

    2014-01-01

    Aorta dissection is a serious vascular disease produced by a rupture of the tunica intima of the vessel wall that can be lethal to the patient. The related diagnosis is strongly based on images, where the multi-detector CT is the most generally used modality. We aim at developing a semi-automatic segmentation tool for aorta dissections, which will isolate the dissection (or flap) from the rest of the vascular structure. The proposed method is based on different stages, the first one being the semi-automatic extraction of the aorta centerline and its main branches, allowing an subsequent automatic segmentation of the outer wall of the aorta, based on a geodesic level set framework. This segmentation is then followed by an extraction the center of the dissected wall as a 3D mesh using an original algorithm based on the zero crossing of two vector fields. Our method has been applied to five datasets from three patients with chronic aortic dissection. The comparison with manually segmented dissections shows an average absolute distance value of about half a voxel. We believe that the proposed method, which tries to solve a problem that has attracted little attention to the medical image processing community, provides a new and interesting tool to isolate the intimal flap that can provide very useful information to the clinician. PMID:24161795

  11. Frequency of sternal foramen evaluated by MDCT: a minor variation of great relevance.

    PubMed

    Babinski, Marcio A; de Lemos, Leandro; Babinski, Monique S D; Gonçalves, Marianna V T; De Paula, Rafael C; Fernandes, Rodrigo M P

    2015-04-01

    Due to inadvertent cardiac or great vessel injury, sternal foramina may pose as a great hazard during sternal puncture. They can also be misinterpreted as osteolytic lesions in cross-sectional imaging of the sternum. The distribution of these variations differs between populations, but data from Brazilians are scarcely reported. Therefore, this study aimed to verify the frequency of midline sternal foramen and double-ended xiphoid process, as developmental variations, in order to avoid fatal complications following sternal puncture of sternal acupuncture treatment. A total of 114 chest computed tomograms were evaluated. The frequency of midline sternal foramen in a complication risk bearing feature is of approximately 10.5%. The double-ended xiphoid process was present in 17.5%. We conclude that sternal acupuncture should be planned in the region of corpus-previous CT should be done to rule out this variation. Furthermore, we strongly recommend the acupuncture technique which prescribes a safe superficial-oblique approach to the sternum. PMID:25023390

  12. Simultaneous thrombosis of superior mesenteric artery and superior mesenteric vein following chemotherapy: MDCT findings.

    PubMed

    Olgun, Deniz Cebi; Bakan, Selim; Samanci, Cesur; Tutar, Onur; Demiryas, Suleyman; Korkmazer, Bora; Kantarci, Fatih

    2014-02-01

    A case of acute mesenteric ischemia due to thrombosis of superior mesenteric artery and vein in a 44-year-old woman following chemotherapy for invasive laryngeal carcinoma was diagnosed on a multi-detector CT scan. Although the link between malignancy and thromboembolism is widely recognized in patients with cancer, chemotherapy further elevates the risk of thrombosis. Acute mesenteric ischemia associated or not associated with chemotherapy rarely occurs in patients with cancer. Moreover, co-occurrence of superior mesenteric artery and superior mesenteric vein thrombosis is reported for the first time.

  13. A numerical study of heat and water vapor transfer in MDCT-based human airway models.

    PubMed

    Wu, Dan; Tawhai, Merryn H; Hoffman, Eric A; Lin, Ching-Long

    2014-10-01

    A three-dimensional (3D) thermo-fluid model is developed to study regional distributions of temperature and water vapor in three multi-detector row computed-tomography-based human airways with minute ventilations of 6, 15 and 30 L/min. A one-dimensional (1D) model is also solved to provide necessary initial and boundary conditions for the 3D model. Both 3D and 1D predicted temperature distributions agree well with available in vivo measurement data. On inspiration, the 3D cold high-speed air stream is split at the bifurcation to form secondary flows, with its cold regions biased toward the inner wall. The cold air flowing along the wall is warmed up more rapidly than the air in the lumen center. The repeated splitting pattern of air streams caused by bifurcations acts as an effective mechanism for rapid heat and mass transfer in 3D. This provides a key difference from the 1D model, where heating relies largely on diffusion in the radial direction, thus significantly affecting gradient-dependent variables, such as energy flux and water loss rate. We then propose the correlations for respective heat and mass transfer in the airways of up to 6 generations: [Formula: see text] and [Formula: see text], where Nu is the Nusselt number, Sh is the Sherwood number, Re is the branch Reynolds number, D a is the airway equivalent diameter, and [Formula: see text] is the tracheal equivalent diameter.

  14. Interrupted Aortic Arch Associated with Absence of Left Common Carotid Artery: Imaging with MDCT

    SciTech Connect

    Onbas, Omer Olgun, Hasim; Ceviz, Naci; Ors, Rahmi; Okur, Adnan

    2006-06-15

    Interrupted aortic arch (IAA) is a rare severe congenital heart defect defined as complete luminal and anatomic discontinuity between ascending and descending aorta. Although its association with various congenital heart defects has been reported, absence of left common carotid artery (CCA) in patients with IAA has not been reported previously. We report a case of IAA associated with the absence of left CCA which was clearly shown on multidetector-row spiral CT.

  15. The spectrum of facial fractures in motor vehicle accidents: an MDCT study of 374 patients.

    PubMed

    Peltola, Elina M; Koivikko, Mika P; Koskinen, Seppo K

    2014-04-01

    Road traffic accidents are a major health problem worldwide resulting frequently in maxillofacial injuries. The purpose of the study was to assess the incidence and spectrum of facial fractures in patients involved in a motor vehicle accident (MVA). Using picture archiving and communication system, all requests for suspected facial trauma were retrieved during a 62-month period; 374 met the inclusion criteria. Two researchers interpreted the multidetector computed tomography images by consensus. The motor vehicles involved were divided into two groups: those involving a passenger car or a larger vehicle and those involving a motorized two-wheeler. Furthermore, the motor vehicle accidents were divided into collisions and run-off-road accidents. Of the 374 patients (aged 15-80, mean 34), 271 (72 %) were male and 103 (28 %) female. Of all patients, 262 (70 %) had a facial or skull base fracture; of these, multiple separate fractures were present in 56 %. Nasal fractures were the most common fractures followed by orbital, skull base, and maxillary fractures. Frontal bone, LeFort, and zygomatic arch fractures were always accompanied by other fractures. Fractures were more frequent in the group of collisions compared with run-off-road accidents. In the two-wheeled group, only 15 % did not have facial or skull base fractures. Fractures often occur in multitudes as 39 % of all patients have multiple facial or skull bone fractures, and thus, emergency radiologists should be familiar with the complexity of the injuries. Negative clear sinus sign and low-energy sentinel injuries should be trusted as indications of undetected injuries in MVA victims. PMID:24221020

  16. Extra-intestinal malignancies in inflammatory bowel diseases: An update with emphasis on MDCT and MR imaging features.

    PubMed

    Dohan, A; Faraoun, S A; Barral, M; Guerrache, Y; Boudiaf, M; Dray, X; Hoeffel, C; Allez, M; Farges, O; Beaugerie, L; Aparicio, T; Marteau, P; Fishman, E K; Lucidarme, O; Eveno, C; Pocard, M; Dautry, R; Soyer, P

    2015-09-01

    Inflammatory bowel diseases (IBD) are associated with an increased risk of gastrointestinal cancers and more specifically in sites affected by chronic inflammation. However, patients with IBD have also an increased risk for developing a variety of extra-intestinal cancers. In this regard, hepatobiliary cancers, such as cholangiocarcinoma, are more frequently observed in IBD patients because of a high prevalence of primary sclerosing cholangitis, which is considered as a favoring condition. Extra-intestinal lymphomas, mostly non-Hodgkin lymphomas, and skin cancers are also observed with an increased incidence in IBD patients by comparison with that in patients without IBD. This review provides an update on demographics, risk factors and clinical features of extra-intestinal malignancies, including cholangiocarcinoma, hepatocellular carcinoma and lymphoma, that occur in patients with IBD along with a special emphasis on the multidetector row computed tomography and magnetic resonance imaging features of these uncommon conditions. PMID:25846686

  17. Low Dose MDCT with Tube Current Modulation: Role in Detection of Urolithiasis and Patient Effective Dose Reduction

    PubMed Central

    Kakkar, Chandan; Sripathi, Smiti; Parakh, Anushri; Shrivastav, Rajendra

    2016-01-01

    Introduction Urolithiasis is one of the major, recurring problem in young individuals and CT being the commonest diagnostic modality used. In order to reduce the radiation dose to the patient who are young and as stone formation is a recurring process; one of the simplest way would be, low dose CT along with tube current modulation. Aim Aim of this study was to compare the sensitivity and specificity of low dose (70mAs) with standard dose (250mAs) protocol in detecting urolithiasis and to define the tube current and mean effective patient dose by these protocols. Materials and Methods A prospective study was conducted in 200 patients over a period of 2 years with acute flank pain presentation. CT was performed in 100 cases with standard dose and another 100 with low dose protocol using tube current modulation. Sensitivity and specificity for calculus detection, percentage reduction of dose and tube current with low dose protocol was calculated. Results Urolithiasis was detected in 138 patients, 67 were examined by high dose and 71 were by low dose protocol. Sensitivity and Specificity of low dose protocol was 97.1% and 96.4% with similar results found in high BMI patients. Tube current modulation resulted in reduction of effective tube current by 12.17%. The mean effective patient dose for standard dose was 10.33 mSv whereas 2.92 mSv for low dose with 51.13–53.8% reduction in low dose protocol. Conclusion The study has reinforced that low-dose CT with tube current modulation is appropriate for diagnosis of urolithiasis with significant reduction in tube current and patient effective dose. PMID:27437322

  18. MDCT-based quantification of porcine pulmonary arterial morphometry and self-similarity of arterial branching geometry.

    PubMed

    Lee, Yik Ching; Clark, Alys R; Fuld, Matthew K; Haynes, Susan; Divekar, Abhay A; Hoffman, Eric A; Tawhai, Merryn H

    2013-05-01

    The pig is frequently used as an experimental model for studies of the pulmonary circulation, yet the branching and dimensional geometry of the porcine pulmonary vasculature remains poorly defined. The purposes of this study are to improve the geometric definition of the porcine pulmonary arteries and to determine whether the arterial tree exhibits self-similarity in its branching geometry. Five animals were imaged using thin slice spiral computed tomography in the prone posture during airway inflation pressure at 25 cmH2O. The luminal diameter and distance from the inlet of the left and right pulmonary arteries were measured along the left and right main arterial pathway in each lung of each animal. A further six minor pathways were measured in a single animal. The similarity in the rate of reduction of diameter with distance of all minor pathways and the two main pathways, along with similarity in the number of branches arising along the pathways, supports self-similarity in the arterial tree. The rate of reduction in diameter with distance from the inlet was not significantly different among the five animals (P > 0.48) when normalized for main pulmonary artery diameter and total main artery pathlength, which supports intersubject similarity. Other metrics to quantify the tree geometry are strikingly similar to those from airways of other quadrupeds, with the exception of a significantly larger length to diameter ratio, which is more appropriate for the vascular tree. A simplifying self-similar model for the porcine pulmonary arteries is proposed to capture the important geometric features of the arterial tree. PMID:23449941

  19. Change in the Growth Rate of Localized Pancreatic Adenocarcinoma in Response to Gemcitabine, Bevacizumab, and Radiation Therapy on MDCT

    SciTech Connect

    Rezai, Pedram; Yaghmai, Vahid; Tochetto, Sandra M.; Galizia, Mauricio S.; Miller, Frank H.; Mulcahy, Mary F.; Small, William

    2011-10-01

    Purpose: To depict treatment response to chemoradiotherapy by comparing tumor growth rate between treated and untreated patients and to compare depicted response with objective response according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 guideline. Methods and Materials: This Health Insurance Portability and Accountability Act-compliant, retrospective study was approved by the institutional review board. Volume doubling time (DT) of histologically confirmed locally advanced pancreatic adenocarcinoma was calculated in 16 patients treated with chemoradiotherapy and 10 untreated patients by incorporating interscan interval ({Delta}t) and tumor volume at baseline (V0) and follow-up (V1) obtained by semiautomated segmentation into the following equation: DT = {Delta}t . log 2/log (V1/V0). Reciprocal of doubling time (RDT), which is the linear representation of tumor growth rate, was calculated by use of the following equation: RDT = 365/DT. The lowest RDT value of 2.42 in untreated patients was considered as the cutoff value for depiction of treatment response. Depicted response rate was defined as the proportion of patients with an RDT value of less than 2.42. Depicted response was compared with objective response according to the RECIST 1.1 guideline. The significance level was set at p < 0.05. Results: There was a significant difference in mean RDT between treated (range, -7.12 to 3.27; mean, -1.27; median, -1.30) and untreated (range, 2.42 to 10.74; mean, 5.33; median, 4.26) patients (p < 0.05). Reciprocal of doubling time was less than 2.42 in 14 treated patients, which corresponded to a depicted response rate of 87.50% as opposed to the objective response rate of 18.75% according to the RECIST 1.1 guideline (p < 0.05) and carbohydrate antigen 19-9 response rate of 62.50% (p > 0.05). Carbohydrate antigen 19-9 response was concordant with RDT and RECIST response in 12 patients (75.00%) ({kappa}, 0.38) and 9 patients (56.25%) ({kappa}, 0.24), respectively. Conclusions: There was a significant difference between depicted response according to RDT and objective response according to RECIST. Reciprocal of doubling time might serve as a valuable biomarker for evaluation of treatment response when depiction of small changes in tumor size is concerned.

  20. MDCT of right aortic arch with aberrant left subclavian artery associated with kommerell diverticulum and calcified ligamentum arteriosum.

    PubMed

    Kanza, Rene Epunza; Berube, Michel; Michaud, Pierre

    2013-04-28

    We present a case of the right aortic arch with kommerell diverticulum (KD) and aberrant left subclavian artery in a symptomatic 50-year-old patient with a calcification in the presumed attachment site of the ligamentum arteriosum (LA) to the KD. In another 30-year-old male patient, the entire course of a calcified LA was demonstrated using multidetector row computed tomography.

  1. MDCT of right aortic arch with aberrant left subclavian artery associated with kommerell diverticulum and calcified ligamentum arteriosum

    PubMed Central

    Kanza, Rene Epunza; Berube, Michel; Michaud, Pierre

    2013-01-01

    We present a case of the right aortic arch with kommerell diverticulum (KD) and aberrant left subclavian artery in a symptomatic 50-year-old patient with a calcification in the presumed attachment site of the ligamentum arteriosum (LA) to the KD. In another 30-year-old male patient, the entire course of a calcified LA was demonstrated using multidetector row computed tomography. PMID:23671755

  2. MDCT and clinicopathological features of small bowel gastrointestinal stromal tumours in 102 patients: a single institute experience

    PubMed Central

    Shinagare, A B; O'Neill, A C; Krajewski, K M; Hornick, J L; George, S; Ramaiya, N H; Tirumani, S H

    2015-01-01

    Objective: Small bowel (SB) is the second most common site of gastrointestinal stromal tumours (GISTs). We evaluated clinical presentation, pathology, imaging features and metastatic pattern of SB GIST. Methods: Imaging and clinicopathological data of 102 patients with jejunal/ileal GIST treated at Dana-Farber Cancer Institute and Brigham and Women's Hospital (Boston, MA) between 2002 and 2013 were evaluated. Imaging of treatment-naive primary tumour (41 patients) and follow-up imaging in all patients was reviewed. Results: 90/102 patients were symptomatic at presentation, abdominal pain and lower gastrointestinal blood loss being the most common symptoms. On pathology, 21 GISTs were low risk, 17 were intermediate and 64 were high risk. The mean tumour size was 8.5 cm. On baseline CT (n = 41), tumours were predominantly well circumscribed, exophytic and smooth/mildly lobulated in contour. Of 41 tumours, 16 (39%) were homogeneous, whereas 25 (61%) were heterogeneous. Of the 41 tumours, cystic/necrotic areas (Hounsfield units < 20) were seen in 16 (39%) and calcifications in 9 (22%). CT demonstrated complications in 13/41 (32%) patients in the form of tumour–bowel fistula (TBF) (7/41), bowel obstruction (4/41) and intraperitoneal rupture (2/41). Amongst 102 total patients, metastases developed in 51 (50%) patients (27 at presentation), predominantly involving peritoneum (40/102) and liver (32/102). 7/8 (87%) patients having intraperitoneal rupture at presentation developed metastases. Metastases elsewhere were always associated with hepatic/peritoneal metastases. At last follow-up, 28 patients were deceased (median survival, 65 months). Conclusion: SB GISTs were predominantly large, well-circumscribed, exophytic tumours with or without cystic/necrotic areas. Complications such as TBF, bowel obstruction and intraperitoneal perforation were visualized at presentation, with patients with perforation demonstrating a high risk of metastatic disease. Exophytic eccentric bowel wall involvement and lack of associated adenopathy are useful indicators to help differentiate GISTs from other SB neoplasms. Advances in knowledge: SB GISTs are predominantly large, well-circumscribed, exophytic tumours, and may present with complications. They often are symptomatic at presentation, are high risk on pathology and metastasize to the peritoneum more commonly than the liver. PMID:26111069

  3. Preoperative evaluation of the ulnar collateral ligament by magnetic resonance imaging and computed tomography arthrography. Evaluation in 25 baseball players with surgical confirmation.

    PubMed

    Timmerman, L A; Schwartz, M L; Andrews, J R

    1994-01-01

    A prospective study was completed on 25 baseball players with medial side elbow pain. They were evaluated preoperatively with both computed tomography arthrogram and magnetic resonance imaging examinations of the elbow to assess the ulnar collateral ligament. At surgery, 16 of 25 patients had an abnormal ulnar collateral ligament and 9 patients had a normal ulnar collateral ligament. The computed tomography arthrogram detected abnormalities in 12 of the 14 patients with ulnar collateral ligament tearing (sensitivity, 86%). The magnetic resonance imaging scan indicated abnormalities in 8 of 14 patients (sensitivity, 57%). The specificity of the computed tomography arthrogram was 91% and the magnetic resonance imaging was 100%. A newly described "T-sign" was seen on the computed tomography arthrogram in the patients with an undersurface tear of the ulnar collateral ligament. This represented the dye leaking around the detachment of the ulnar collateral ligament from its bony insertion but remaining contained within the intact superficial layer of the ulnar collateral ligament and capsule. Both the computed tomography arthrogram and the magnetic resonance imaging scan were accurate in diagnosing a complete tear of the ulnar collateral ligament preoperatively in all cases. The main advantage of the computed tomography arthrogram was in evaluating the partial undersurface tear.

  4. QUANTITATIVE PLANAR AND VOLUMETRIC CARDIAC MEASUREMENTS USING 64 MDCT AND 3T MRI VS. STANDARD 2D AND M-MODE ECHOCARDIOGRAPHY: DOES ANESTHETIC PROTOCOL MATTER?

    PubMed

    Drees, Randi; Johnson, Rebecca A; Stepien, Rebecca L; Munoz Del Rio, Alejandro; Saunders, Jimmy H; François, Christopher J

    2015-01-01

    Cross-sectional imaging of the heart utilizing computed tomography and magnetic resonance imaging (MRI) has been shown to be superior for the evaluation of cardiac morphology and systolic function in humans compared to echocardiography. The purpose of this prospective study was to test the effects of two different anesthetic protocols on cardiac measurements in 10 healthy beagle dogs using 64-multidetector row computed tomographic angiography (64-MDCTA), 3T magnetic resonance (MRI) and standard awake echocardiography. Both anesthetic protocols used propofol for induction and isoflourane for anesthetic maintenance. In addition, protocol A used midazolam/fentanyl and protocol B used dexmedetomedine as premedication and constant rate infusion during the procedure. Significant elevations in systolic and mean blood pressure were present when using protocol B. There was overall good agreement between the variables of cardiac size and systolic function generated from the MDCTA and MRI exams and no significant difference was found when comparing the variables acquired using either anesthetic protocol within each modality. Systolic function variables generated using 64-MDCTA and 3T MRI were only able to predict the left ventricular end diastolic volume as measured during awake echocardiogram when using protocol B and 64-MDCTA. For all other systolic function variables, prediction of awake echocardiographic results was not possible (P = 1). Planar variables acquired using MDCTA or MRI did not allow prediction of the corresponding measurements generated using echocardiography in the awake patients (P = 1). Future studies are needed to validate this approach in a more varied population and clinically affected dogs.

  5. MDCT in ischaemic colitis: how to define the aetiology and acute, subacute and chronic phase of damage in the emergency setting.

    PubMed

    Berritto, Daniela; Iacobellis, Francesca; Mazzei, Maria Antonietta; Volterrani, Luca; Guglielmi, Giuseppe; Brunese, Luca; Grassi, Roberto

    2016-01-01

    Ischemic colitis (IC) is the most common vascular disorder of the gastrointestinal tract with a reported incidence of 6.1-44 cases/100,000 person years with confirmatory histopathology. However, the true incidence of IC poses some difficulty, and even vigilant clinicians with patients at high risk often miss the diagnosis, since clinical presentation is non-specific or could have a mild transient nature. Detection of IC results is crucial to plan the correct therapeutic approach and reduce the reported mortality rate (4-12%). Diagnosis of IC is based on a combination of clinical suspicion, radiological, endoscopic and histological findings. Some consider colonoscopy as a diagnostic test of choice; however, preparation is required and it is not without risk, above all in patients who are severely ill. There are two manifestations of vascular colonic insult: ischaemic and reperfusive. The first one occurs above all during ischaemic/non-occlusive mesenteric ischaemia; in this case, the colonic wall appears thinned with dilated lumen and fluid appears in the paracolic space. When reperfusion occurs, the large bowel wall appears thickened and stratified, because of subepithelial oedema and/or haemorrhage, with consequent lumen calibre reduction. Shaggy contour of the involved intestine and misty mesentery are associated with the pericolic fluid. The pericolic fluid results are a crucial finding for IC diagnosis since its evidence suggests the presence of an ongoing damage thus focusing the attention on other pathological aspects which could be otherwise misdiagnosed, such as thinned or thickened colonic wall. Moreover, the pericolic fluid may increase or decrease, depending on the evolution of the ischaemic damage, suggesting the decision of medical or surgical treatment. Radiologists should not forget the hypothesis of IC, being aware that multidetector CT could be sufficient to suggest the diagnosis of IC, allowing for early identification and grading definition, and in a short-term follow-up, discriminating patients who need urgent surgery from patients in whom medical treatment and follow-up can be proposed. PMID:27007462

  6. Quantitative planar and volumetric cardiac measurements using 64 MDCT and 3T MRI versus standard 2D and M-mode echocardiography: Does anesthetic protocol matter?

    PubMed Central

    Drees, Randi; Johnson, Rebecca A; Stepien, Rebecca L; Rio, Alejandro Munoz Del; Saunders, Jimmy H; François, Christopher J

    2016-01-01

    Cross-sectional imaging of the heart utilizing computed tomography (CT) and magnetic resonance imaging (MRI) has been shown to be superior for the evaluation of cardiac morphology and systolic function in humans compared to echocardiography. The purpose of this prospective study was to test the effects of two different anesthetic protocols on cardiac measurements in 10 healthy beagle dogs using 64-multidetector row computed tomographic angiography (64-MDCTA), 3T magnetic resonance (MRI) and standard awake echocardiography. Both anesthetic protocols used propofol for induction and isoflourane for anesthetic maintenance. In addition, protocol A used midazolam/fentanyl and protocol B used dexmedetomedine as premedication and constant rate infusion during the procedure. Significant elevations in systolic and mean blood pressure were present when using protocol B. There was overall good agreement between the variables of cardiac size and systolic function generated from the MDCTA and MRI exams and no significant difference was found when comparing the variables acquired using either anesthetic protocol within each modality. Systolic function variables generated using 64-MDCTA and 3T MRI were only able to predict the left ventricular end diastolic volume as measured during awake echocardiogram when using protocol B and 64-MDCTA. For all other systolic function variables, prediction of awake echocardiographic results was not possible (P = 1). Planar variables acquired using MDCTA or MRI did not allow prediction of the corresponding measurements generated using echocardiography in the awake patients (P=1). Future studies are needed to validate this approach in a more varied population and clinically affected dogs. PMID:26082285

  7. QUANTITATIVE PLANAR AND VOLUMETRIC CARDIAC MEASUREMENTS USING 64 MDCT AND 3T MRI VS. STANDARD 2D AND M-MODE ECHOCARDIOGRAPHY: DOES ANESTHETIC PROTOCOL MATTER?

    PubMed

    Drees, Randi; Johnson, Rebecca A; Stepien, Rebecca L; Munoz Del Rio, Alejandro; Saunders, Jimmy H; François, Christopher J

    2015-01-01

    Cross-sectional imaging of the heart utilizing computed tomography and magnetic resonance imaging (MRI) has been shown to be superior for the evaluation of cardiac morphology and systolic function in humans compared to echocardiography. The purpose of this prospective study was to test the effects of two different anesthetic protocols on cardiac measurements in 10 healthy beagle dogs using 64-multidetector row computed tomographic angiography (64-MDCTA), 3T magnetic resonance (MRI) and standard awake echocardiography. Both anesthetic protocols used propofol for induction and isoflourane for anesthetic maintenance. In addition, protocol A used midazolam/fentanyl and protocol B used dexmedetomedine as premedication and constant rate infusion during the procedure. Significant elevations in systolic and mean blood pressure were present when using protocol B. There was overall good agreement between the variables of cardiac size and systolic function generated from the MDCTA and MRI exams and no significant difference was found when comparing the variables acquired using either anesthetic protocol within each modality. Systolic function variables generated using 64-MDCTA and 3T MRI were only able to predict the left ventricular end diastolic volume as measured during awake echocardiogram when using protocol B and 64-MDCTA. For all other systolic function variables, prediction of awake echocardiographic results was not possible (P = 1). Planar variables acquired using MDCTA or MRI did not allow prediction of the corresponding measurements generated using echocardiography in the awake patients (P = 1). Future studies are needed to validate this approach in a more varied population and clinically affected dogs. PMID:26082285

  8. [Is it possible to diagnose idiopathic chondropathia patellae using radiologic methods?].

    PubMed

    Kaufmann, J; Langlotz, M

    1984-10-01

    In a retrospective study of 47 cases of chondromalacia proved by operation, a correct diagnosis had been made by arthrography in three cases. In 44 patients a false negative finding had been obtained. A prospective study was carried out comparing single and double contrast arthrography as well as double contrast arthrotomography and scintigraphy in ten patients with typical chondropathia. It was confirmed by arthroscopy in nine cases. Only two patients with severe chondromalacia showed abnormal findings by arthrography or scintigraphy. Our investigation has led to the conclusion that arthrography is not a suitable method for demonstrating idiopathic chondropathia of the patella.

  9. In-vivo regional myocardial perfusion measurements in a porcine model by ECG-gated multislice computed tomography

    NASA Astrophysics Data System (ADS)

    Stantz, Keith M.; Liang, Yun; Meyer, Cristopher A.; Teague, Shawn; Stecker, Michael; Hutchins, Gary; McLennan, Gordon; Persohn, Scott

    2003-05-01

    Purpose: To evaluate whether functional multi-slice computed tomography (MSCT) can identify regional areas of normally perfused and ischemic myocardium in a porcine model. Material and Methods: Three out bred pigs, two of which had ameroids surgically implanted to constrict flow within the LAD and LCx coronary arteries, were injected with 25 mL of iopromide (Isovue) at a rate of 5 mL/second via the femoral or jugular vein. Sixty axial scans along the short axis of the heart was acquired on a 16-slice CT scanner (Philips MX8000-IDT) triggered at end-diastole of the cardiac cycle and acquiring an image within 270 msec. A second series of scans were taken after an intravenous injection of a vasodilator, 150 μg/kg/min of adenosine. ROIs were drawn around the myocardial tissue and the resulting time-density curves were used to extract perfusion values. Results: Determination of the myocardial perfusion and fractional blood volume implementing three different perfusion models. A 5-point averaging or 'smoothing' algorithm was employed to effectively filter the data due to its noisy nature. The (preliminary) average perfusion and fractional blood volume values over selected axial slices for the pig without an artificially induced stenosis were measured to be 84 +/- 22 mL/min/100g-tissue and 0.17 +/- 0.04 mL/g-tissue, the former is consistent with PET scan and EBCT results. The pig with a stenosis in the left LAD coronary artery showed a reduced global perfusion value -- 45 mL/min/100g-tissue. Correlations in regional perfusion values relative to the stenosis were weak. During the infusion of adenosine, averaged perfusion values for the three subjects increased by 46 (+/-45) percent, comparable to increases measured with PET. Conclusion: Quantifying global perfusion values using MDCT appear encouraging. Future work will focus resolving the systematic effects from noise due to signal fluctuation from the porcine tachyardia (80-93 BPM) and provide a more robust measurement

  10. Joint x-ray

    MedlinePlus

    X-ray - joint; Arthrography; Arthrogram ... x-ray technologist will help you position the joint to be x-rayed on the table. Once in place, pictures are taken. The joint may be moved into other positions for more ...

  11. Comparison of the accuracy of multidetector computed tomography versus two-dimensional echocardiography to measure left atrial volume.

    PubMed

    Avelar, Erick; Durst, Ronen; Rosito, Guido A; Thangaroopan, Molly; Kumar, Simi; Tournoux, Francois; Chan, Raymond C; Hung, Judy; Hoffmann, Udo; Abbara, Suhny; Brady, Thomas; Cury, Ricardo C

    2010-07-01

    Left atrial (LA) volume is an important prognostic factor in cardiovascular disease. Multidetector computed tomography (MDCT) is an emerging cardiac imaging modality; however, its accuracy in measuring the LA volume has not been well studied. The aim of our study was to determine the accuracy of MDCT in quantifying the LA volume. A total of 48 patients underwent MDCT and 2-dimensional (2D) echocardiography (2DE) on the same day. The area-length and Simpson's methods were used to obtain the 2D echocardiographic LA volume. The LA volume assessment by MDCT was obtained using the modified Simpson's method. Four artificial phantoms were created, and their true volume was assessed by an independent observer using both imaging modalities. The correlation between the LA volume by MDCT and 2DE was significant (r = 0.68). The mean 2D echocardiographic LA volume was lower than the LA volume obtained with MDCT (2DE 79 +/- 37 vs MDCT 103 +/- 32, p <0.05). In the phantom experiment, the volume obtained using MDCT and 2DE correlated significantly with the true volume (r = 0.97, p <0.05 vs r = 0.96, p <0.05, respectively). However, the mean 2D echocardiographic phantom volume was 16% lower than the true volume (2DE, Simpson's method 53 +/- 24 vs the true volume 61 +/- 24, p <0.05). The mean volume calculated using MDCT did not differ from the true volume (MDCT 60 +/- 21 vs true volume 61 +/- 24, p = NS). 2DE appeared to systematically underestimate the LA volume compared to phantom and cardiac MDCT, suggesting that different normal cutoff values should be used for each modality. In conclusion, LA volume quantification using MDCT is an accurate and feasible method. PMID:20609656

  12. Clinical application of 320-row multidetector computed tomography for a dynamic three-dimensional vascular study: imaging findings and initial experience.

    PubMed

    Nagamatsu, Shogo; Nakagawa, Masahiro; Kayano, Shuji; Koizumi, Takuya; Akazawa, Satoshi; Onitsuka, Tetsuro; Iida, Yoshiyuki; Endo, Masahiro; Nakaya, Yoshihiro; Urikura, Atsushi

    2010-10-01

    The 320-row multidetector computed tomography (MDCT) is now used by both cardiologists and neurosurgeons. It enables dynamic 3D-CT angiography, because the wide-area detector eliminates helical scanning, thus achieving very fast scanning times for single 3D-CT volume data. Some microvascular surgeons are familiar with 64-row MDCT for perforator studies, but there are few reports of studies using 320-row MDCT. This MDCT system was used to follow the dynamic blood flow of small vessels. It is considered to have a great potential in the clinical field of microvascular surgery. PMID:20399163

  13. Efficacy of Multidetector-Row Computed Tomography as a Practical Tool in Comparison to Invasive Procedures for Visualization of the Biliary Obstruction

    PubMed Central

    Taheri, Abdolmajid; Rostamzadeh, Ayoob; Gharib, Alireza; Fatehi, Daryoush

    2016-01-01

    Introduction: Recently, multidetector computed tomography (MDCT) has been introduced into clinical practice. MDCT has become the noninvasive diagnostic test of choice for detailed evaluation of biliary obstruction. Aim: the main objective of the present study was to evaluate the diagnostic value of MDCT compared to invasive procedures for detecting biliary obstruction causes. Material and Methods: Since February 2009 until May 2011 fifty biliary obstruction patients based on clinical, laboratory or ultrasonographic findings, were evaluated by Multidetector-row computed tomography. The causes of biliary obstruction, which was identified using. MDCT were classified into three categories: calculus, benign stricture, and malignancy. Final diagnosis was conducted based on percutaneous transhepatic cholangiography (PTC), endoscopic retrograde cholangiopancreatography, biopsy, or surgery. The MDCT diagnosis and were compared with the final diagnosis. Results: A correct diagnosis of causes of biliaryobstruction was made on the basis of MDCT findings for 44 of the total 50 patients. Two patients with chronic pancreatitis were incorrectly diagnosed with a pancreatic head adenocarcinoma on the basis of MDCT findings. One patient with biliary stone was incorrectly diagnosed with a periampullary adenocarcinoma on the basis of MDCT findings. The Sensitivity, specificity and accuracy of MDCT in the diagnosis of causes of biliary obstruction were 94.12% and87.87% and94.6% respectively. Conclusion: Based on the findings of this study MDCT has an excellent image quality, providing valuable information about the biliary tree and other abdominal organs. The use of advanced image processing, including maximum intensity projection and multiplanar reconstruction (especially coronal or sagittal reformatted images), allows superior visualization of the biliary tree and vascular structures. Three-dimensional reconstruction images complement axial images by providing a more anatomically

  14. Update on the imaging diagnosis of otosclerosis.

    PubMed

    Gredilla Molinero, J; Mancheño Losa, M; Santamaría Guinea, N; Arévalo Galeano, N; Grande Bárez, M

    2016-01-01

    Otosclerosis is a primary osteodystrophy of the temporal bone that causes progressive conductive hearing loss. The diagnosis is generally clinical, but multidetector CT (MDCT), the imaging technique of choice, is sometimes necessary. The objective of this article is to systematically review the usefulness of imaging techniques for the diagnosis and postsurgical assessment of otosclerosis, fundamentally the role of MDCT, to decrease the surgical risk.

  15. Comparison of Diagnostic Accuracy of Radiation Dose-Equivalent Radiography, Multidetector Computed Tomography and Cone Beam Computed Tomography for Fractures of Adult Cadaveric Wrists

    PubMed Central

    Neubauer, Jakob; Benndorf, Matthias; Reidelbach, Carolin; Krauß, Tobias; Lampert, Florian; Zajonc, Horst; Kotter, Elmar; Langer, Mathias; Fiebich, Martin; Goerke, Sebastian M.

    2016-01-01

    Purpose To compare the diagnostic accuracy of radiography, to radiography equivalent dose multidetector computed tomography (RED-MDCT) and to radiography equivalent dose cone beam computed tomography (RED-CBCT) for wrist fractures. Methods As study subjects we obtained 10 cadaveric human hands from body donors. Distal radius, distal ulna and carpal bones (n = 100) were artificially fractured in random order in a controlled experimental setting. We performed radiation dose equivalent radiography (settings as in standard clinical care), RED-MDCT in a 320 row MDCT with single shot mode and RED-CBCT in a device dedicated to musculoskeletal imaging. Three raters independently evaluated the resulting images for fractures and the level of confidence for each finding. Gold standard was evaluated by consensus reading of a high-dose MDCT. Results Pooled sensitivity was higher in RED-MDCT with 0.89 and RED-MDCT with 0.81 compared to radiography with 0.54 (P = < .004). No significant differences were detected concerning the modalities’ specificities (with values between P = .98). Raters' confidence was higher in RED-MDCT and RED-CBCT compared to radiography (P < .001). Conclusion The diagnostic accuracy of RED-MDCT and RED-CBCT for wrist fractures proved to be similar and in some parts even higher compared to radiography. Readers are more confident in their reporting with the cross sectional modalities. Dose equivalent cross sectional computed tomography of the wrist could replace plain radiography for fracture diagnosis in the long run. PMID:27788215

  16. Newer cardiac imaging techniques: multidetector CT angiography.

    PubMed

    Davidoff, Ravin; Ruberg, Frederick L

    2006-01-01

    An update of new developments with multidetector computed tomography (MDCT) coronary angiography is presented. Similar to what has occurred with the introduction of other new technologies such as electron beam computed tomography (EBCT), life insurance medical directors are expected to evaluate a technology before there are sufficient data from large clinical trials. Well-performed studies of the performance of MDCT coronary angiography have only recently appeared. MDCT appears to perform well for excluding significant coronary disease, and will perhaps be useful in emergency room "rule-out" situations. Other applications may be for the diagnosis of significant coronary obstruction (> 75% stenosis), as well as for the evaluation of bypass grafts. Limitations include the requirement for radiologic contrast administration and significant radiation exposure. MDCT does not provide information on atheroma morphology. Given these limitations, MDCT coronary angiography utilization will grow, and it will prove to be a useful tool in specific situations. PMID:16845845

  17. Multidetector-Row Computed Tomography in the Evaluation of Transjugular Intrahepatic Portosystemic Shunt Performed with Expanded-Polytetrafluoroethylene-Covered Stent-Graft

    SciTech Connect

    Fanelli, Fabrizio Bezzi, Mario; Bruni, Antonio; Corona, Mario; Boatta, Emanuele; Lucatelli, Pierleone; Passariello, Roberto

    2011-02-15

    We assessed, in a prospective study, the efficacy of multidetector spiral computed tomography (MDCT) in the evaluation of transjugular intrahepatic portosystemic shunt (TIPS) patency in patients treated with the Viatorr (Gore, Flagstaff, AZ) expanded-polytetrafluoroethylene (e-PTFE)-covered stent-graft. Eighty patients who underwent TIPS procedure using the Viatorr self-expanding e-PTFE stent-graft were evaluated at follow-up of 1, 3, 6, and 12 months with clinical and laboratory tests as well as ultrasound-color Doppler (USCD) imaging. In case of varices, upper gastrointestinal endoscopy was also performed. In addition, the shunt was evaluated using MDCT at 6 and 12 months. In all cases of abnormal findings and discrepancy between MDCT and USCD, invasive control venography was performed. MDCT images were acquired before and after injection of intravenous contrast media on the axial plane and after three-dimensional reconstruction using different algorithms. MDCT was successfully performed in all patients. No artefacts correlated to the Viatorr stent-graft were observed. A missing correlation between UCSD and MDCT was noticed in 20 of 80 (25%) patients. Invasive control venography confirmed shunt patency in 16 (80%) cases and shunt malfunction in 4 (20%) cases. According to these data, MDCT sensitivity was 95.2%; specificity was 96.6%; and positive (PPV) and negative predictive values (NPV) were 90.9 and 98.2%, respectively. USCD sensitivity was 90%; specificity was 75%; and PPV and NPV were 54.5 and 95.7%, respectively. A high correlation (K value = 0.85) between MDCT and invasive control venography was observed. On the basis of these results, MDCT shows superior sensitivity and specificity compared with USCD in those patients in whom TIPS was performed with the Viatorr stent-graft. MDCT can be considered a valid tool in the follow-up of these patients.

  18. Four- and Eight-Channel Aortoiliac CT Angiography: A Comparative Study

    SciTech Connect

    Karcaaltincaba, Musturay Foley, Dennis

    2005-04-15

    Purpose. To compare performance parameters, contrast material load and radiation dose in a patient cohort having aortoiliac CT angiography using 4- and 8-channel multidetector CT (MDCT) systems. Methods. Eighteen patients with abdominal aortic aneurysms underwent initial 4-channel and follow-up 8-channel MDCT angiography. Both the 4- and 8-channel MDCT systems utilized a matrix detector of 16 x 1.25 mm rows. Scan coverage included the abdominal aorta and iliac arteries to the level of the proximal femoral arteries. For 4-channel MDCT, nominal slice thickness and beam pitch were 1.25 mm and 1.5, respectively, and for 8-channel MDCT they were 1.25 mm and 1.35 or 1.65 respectively. Scan duration, iodinated contrast material load and mean aortoiliac attenuation were compared retrospectively. Comparative radiation dose measurements for 4- and 8-channel MDCT were obtained using a multiple scan average dose technique on an abdominal phantom. Results. Compared with 4-channel MDCT, 8-channel MDCT aortoiliac angiography was performed with equivalent collimation, decreased contrast load (mean 45% decrease: 144 ml versus 83 ml of 300 mg iodine/ml contrast material) and decreased acquisition time (mean 51% shorter: 34.4 sec versus 16.9 sec) without a significant change in mean aortic enhancement (299 HU versus 300 HU, p > 0.05). Radiation dose was 2 rad for the 4-channel system and 2/1.5 rad for the 8-channel system at 1.35/1.65 pitch respectively. Conclusion. Compared with 4-channel MDCT, aortoiliac CT angiography with 8-channel MDCT produces equivalent z-axis resolution with decreased contrast load and acquisition time without increased radiation exposure.

  19. Ulnar-sided wrist pain. II. Clinical imaging and treatment

    PubMed Central

    Watanabe, Atsuya; Souza, Felipe; Vezeridis, Peter S.; Blazar, Philip

    2009-01-01

    Pain at the ulnar aspect of the wrist is a diagnostic challenge for hand surgeons and radiologists due to the small and complex anatomical structures involved. In this article, imaging modalities including radiography, arthrography, ultrasound (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography are compared with regard to differential diagnosis. Clinical imaging findings are reviewed for a more comprehensive understanding of this disorder. Treatments for the common diseases that cause the ulnar-sided wrist pain including extensor carpi ulnaris (ECU) tendonitis, flexor carpi ulnaris (FCU) tendonitis, pisotriquetral arthritis, triangular fibrocartilage complex (TFCC) lesions, ulnar impaction, lunotriquetral (LT) instability, and distal radioulnar joint (DRUJ) instability are reviewed. PMID:20012039

  20. Synovial plicae of the knee

    SciTech Connect

    Apple, J.S.; Martinez, S.; Daffner, R.H.; Gehweiler, J.A.; Hardaker, W.T.

    1982-01-01

    This report describes the anatomy, patho-physiology, clinical, and radiographic findings, and treatment of the synovial plicae of the knee joint. The suprapatellar plica is a synovial fold present in the suprapatellar pouch of the knee joint in approximately 20% of the population. This fold may become symptomatic after injury and cause symptoms similar to other common internal derangements of the knee. Double contrast arthrography of the knee can be used to identify the presence of plicae. Although arthrography can identify the presence of a plica, its clinical significance requires close correlation with symptoms and an accurate clinical examination.

  1. Cardiac Multidetector Computed Tomography: Basic Physics of Image Acquisition and Clinical Applications

    PubMed Central

    Bardo, Dianna M.E; Brown, Paul

    2008-01-01

    Cardiac MDCT is here to stay. And, it is more than just imaging coronary arteries. Understanding the differences in and the benefits of one CT scanner from another will help you to optimize the capabilities of the scanner, but requires a basic understanding of the MDCT imaging physics. This review provides key information needed to understand the differences in the types of MDCT scanners, from 64 – 320 detectors, flat panels, single and dual source configurations, step and shoot prospective and retrospective gating, and how each factor influences radiation dose, spatial and temporal resolution, and image noise. PMID:19936200

  2. Secondary aortoenteric fistula: active bleeding detected with multi-detector-row CT.

    PubMed

    Roos, Justus E; Willmann, Jürgen K; Hilfiker, Paul R

    2002-12-01

    We report a case of active bleeding of a secondary aortoenteric fistula (SAEF), in which CT angiography with multi-detector-row CT (MDCT) was finally diagnostic after negative catheter angiography and unsatisfactory endoscopy. The MDCT angiography clearly demonstrated the fistulous tract between the abdominal aortic graft and the duodenum. The dynamic process of bleeding was confirmed as a net increase of contrast agent accumulation in the duodenum through different phases. The MDCT angiography with its excellent 3D image quality is therefore a valuable method in the assessment of active SAEF bleeding. PMID:12522640

  3. Dual-phase CT for the assessment of acute vascular injuries in high-energy blunt trauma: the imaging findings and management implications.

    PubMed

    Iacobellis, Francesca; Ierardi, Anna M; Mazzei, Maria A; Magenta Biasina, Alberto; Carrafiello, Gianpaolo; Nicola, Refky; Scaglione, Mariano

    2016-01-01

    Acute vascular injuries are the second most common cause of fatalities in patients with multiple traumatic injuries; thus, prompt identification and management is essential for patient survival. Over the past few years, multidetector CT (MDCT) using dual-phase scanning protocol has become the imaging modality of choice in high-energy deceleration traumas. The objective of this article was to review the role of dual-phase MDCT in the identification and management of acute vascular injuries, particularly in the chest and abdomen following multiple traumatic injuries. In addition, this article will provide examples of MDCT features of acute vascular injuries with correlative surgical and interventional findings.

  4. Heparin-induced thrombocytopenia (HIT) causing portosplenic, superior mesenteric, and splenic vein thrombosis resulting in splenic rupture and pulmonary emboli formation.

    PubMed

    Lammering, Jeanne C; Wang, David S; Shin, Lewis K

    2012-01-01

    Heparin-induced thrombocytopenia (HIT) is a life-threatening complication of heparin administration. Of the few reported cases of HIT-associated intra-abdominal thrombosis, none to our knowledge provide multidetector-row computed tomography (MDCT) imaging findings or emphasize its utility in diagnosis. We describe a case of HIT with MDCT images demonstrating extensive intra-abdominal thrombosis and end-organ complications including splenic rupture and pulmonary emboli. This case emphasizes the potential role of MDCT in the rapid detection of HIT-related thromboembolic complications in patients with nonspecific abdominal pain.

  5. Primary lung and large airway neoplasms in children: current imaging evaluation with multidetector computed tomography.

    PubMed

    Amini, Behrang; Huang, Steven Y; Tsai, Jason; Benveniste, Marcelo F; Robledo, Hector H; Lee, Edward Y

    2013-07-01

    Multidetector computed tomography (MDCT) offers an important noninvasive imaging modality for confirmation and further characterization of primary lung and large airway neoplasms encountered in pediatric patients. Children represent a unique challenge in imaging, not only because of unique patient factors (eg, inability to follow instructions, motion, need for sedation) but because of the technical factors that must be optimized to reduce radiation dose. This article reviews an MDCT imaging algorithm, up-to-date imaging techniques, and clinical applications of MDCT for evaluating benign and malignant primary neoplasms of lung and large airway in infants and children.

  6. Misty mesentery: a pictorial review of multidetector-row CT findings.

    PubMed

    Filippone, A; Cianci, R; Di Fabio, F; Storto, M L

    2011-04-01

    The term "misty mesentery" indicates a pathological increase in mesenteric fat attenuation at computed tomography (CT). It is frequently observed on multidetector CT (MDCT) scans performed during daily clinical practice and may be caused by various pathological conditions, including oedema, inflammation, haemorrhage, neoplastic infiltration or sclerosing mesenteritis. In patients suffering from acute abdominal disease, misty mesentery may be considered a feature of the underlying disease. Otherwise, it may represent an incidental finding on MDCT performed for other reasons. This article describes the MDCT features of misty mesentery in different diseases in order to provide a rational approach to the differential diagnosis. PMID:21311992

  7. Observational case series: an algorithm incorporating multidetector computed tomography in the medicolegal investigation of human remains after a natural disaster.

    PubMed

    Berran, Philip J; Mazuchowski, Edward L; Marzouk, Abubakr; Harcke, H Theodore

    2014-07-01

    An algorithm incorporating multidetector computed tomography (MDCT), digital radiographs, and external examination was used to triage cases for noninvasive or complete autopsy after a natural disaster. The algorithm was applied to 27 individuals who died during or soon after the earthquake that struck the Republic of Haiti on January 12, 2010. Of the 27 cases reviewed, 7 (26%) required a complete autopsy to determine cause and manner of death. In the remaining 20 (74%), cause and manner of death were determined with a reasonable degree of medical certainty after review of circumstances, an external examination, and postmortem imaging by MDCT and digital radiography (noninvasive autopsy). MDCT was particularly useful in detecting skeletal fractures caused by blunt force injury which were not evident on digital radiographs. The algorithm incorporating postmortem MDCT can be useful in the triage of human remains for autopsy after a natural disaster.

  8. Demonstration of normal and dilated testicular veins by multidetector computed tomography.

    PubMed

    Karcaaltincaba, Musturay

    2011-04-01

    Recent advances in multidetector computed tomography (MDCT) technology enabled better visualization of testicular (gonadal) vein using submillimeter slice thickness and three-dimensional images. Normally, the testicular vein measures 1-3 mm and drains into the inferior vena cava and left renal vein on the right and left sides, respectively. They can be seen in most patients during MDCT studies. Curved planar and volume-rendered images can be used to display testicular veins. We aim to demonstrate MDCT findings of normal testicular vein and its pathologies including varicocele, varices, the testicular vascular pedicle sign, and phlebolith. The testicular vein can be dilated owing to varicocele or portal hypertension and in patients with intraabdominal seminomas arising from undescended testis. The testicular vein can also cause ureteral compression at the crossing point. Understanding MDCT findings of the normal testicular vein and its various pathologies can allow a correct diagnosis, thereby avoiding further diagnostic tests. PMID:21519988

  9. Operational cooling tower model (CTTOOL V1.0)

    SciTech Connect

    Aleman, S.; LocalDomainServers, L.; Garrett, A.

    2015-01-01

    Mechanical draft cooling towers (MDCT’s) are widely used to remove waste heat from industrial processes, including suspected proliferators of weapons of mass destruction (WMD). The temperature of the air being exhausted from the MDCT is proportional to the amount of thermal energy being removed from the process cooling water, although ambient weather conditions and cooling water flow rate must be known or estimated to calculate the rate of thermal energy dissipation (Q). It is theoretically possible to derive MDCT air exhaust temperatures from thermal images taken from a remote sensor. A numerical model of a MDCT is required to translate the air exhaust temperature to a Q. This report describes the MDCT model developed by the Problem Centered Integrated Analysis (PCIA) program that was designed to perform those computational tasks. The PCIA program is a collaborative effort between the Savannah River National Laboratory (SRNL), the Northrop-Grumman Corporation (NG) and the Aerospace Corporation (AERO).

  10. Update on the imaging diagnosis of otosclerosis.

    PubMed

    Gredilla Molinero, J; Mancheño Losa, M; Santamaría Guinea, N; Arévalo Galeano, N; Grande Bárez, M

    2016-01-01

    Otosclerosis is a primary osteodystrophy of the temporal bone that causes progressive conductive hearing loss. The diagnosis is generally clinical, but multidetector CT (MDCT), the imaging technique of choice, is sometimes necessary. The objective of this article is to systematically review the usefulness of imaging techniques for the diagnosis and postsurgical assessment of otosclerosis, fundamentally the role of MDCT, to decrease the surgical risk. PMID:27267384

  11. Multidetector computed tomography evaluation of cavernous haemangioma of the azygous vein.

    PubMed

    Das, Karuna Moy; Ahmed, Ali M; Aljubab, Abdulwahab; Alzoum, Mohammed A

    2013-08-01

    Giant cavernous haemangioma of azygous arch is extremely rare. We present the multidetector computed tomography (MDCT) features of a mediastinal cavernous haemangioma in an asymptomatic child detected in a follow-up examination. MDCT features with multiple venous lakes filling from the periphery, focal specks of calcification, low-density soft tissue mass along with tortuous varicose veins and large feeding veins from the abdomen are suggestive of cavernous haemangioma.

  12. Multi-detector computed tomography of an aortic dissection in a cat.

    PubMed

    Scollan, Katherine; Sisson, David

    2014-03-01

    Contrast enhanced, multi-detector computed tomography (MDCT) is a useful diagnostic imaging modality that has become increasingly available in veterinary medicine. Multi-planar and three-dimensional reconstructions allow accurate and comprehensive assessment of cardiac and vascular lesions with short image acquisition times. ECG-gated, contrast enhanced MDCT was used to assess the lesion extent and therapeutic options in a case of aortic dissection diagnosed in a hypertensive cat. PMID:24485986

  13. Usefulness of Multidetector Row Computed Tomography for Predicting Cardiac Events in Asymptomatic Chronic Kidney Disease Patients at the Initiation of Renal Replacement Therapy

    PubMed Central

    Lee, Jung Eun; Lee, Yong Kyu; Choi, Eun Jeong; Nam, Ji Sun; Choi, Byoung Wook

    2013-01-01

    Background. The prevalence of coronary artery stenosis (CAS) at the initiation of renal replacement therapy (RRT) in chronic kidney disease (CKD) patients has not been fully elucidated. Although coronary angiography is the gold standard in diagnosing CAS its invasiveness and economic burden lead to searching for a noninvasive alternative method. In this study, we evaluated the prevalence of CAS by multidetector row computed tomography (MDCT) and related risk factor to articulate the usefulness of MDCT. Method. Seventy-four asymptomatic CKD patients who began dialysis were evaluated with echocardiography and MDCT. The patients were stratified into two groups according to CAS and coronary artery calcification score (CACS) by MDCT to detect silent CAS and evaluate its predictability for cardiac events. Results. CAS was seen in 24 (32.4%) of 74 asymptomatic CKD patients on MDCT. Both groups showed increasing frequencies of CAS with age (P < 0.01), presence of diabetes (P < 0.05), uric acid level (P < 0.01), and calcium score (P < 0.01). Multiple regression analysis revealed that age and uric acid level were independent risk factors for CAS and high CACS in asymptomatic CKD patients at the initiation of dialysis. Patients with both CAS and high CACS were presented with higher cardiac events rates compared to those without any of them. In Cox regression model, age and the presence of CAS and high CACS on MDCT were an independent risk factor for cardiac events in these patients. Conclusion. We showed that CAS was highly seen in asymptomatic CKD patients starting dialysis. Moreover, both high CACS and CAS on MDCT might predict cardiac events in these patients and MDCT can be a useful screening tool for evaluating coronary artery disease and predicting cardiovascular mortality noninvasively. PMID:24363626

  14. C-arm CT for histomorphometric evaluation of lumbar spine trabecular microarchitecture: a study on anorexia nervosa patients.

    PubMed

    Phan, C M; Khalilzadeh, O; Dinkel, J; Wang, I S; Bredella, M A; Misra, M; Miller, K K; Klibanski, A; Gupta, R

    2013-07-01

    Bone histomorphometry measurements require high spatial resolution that may not be feasible using multidetector CT (MDCT). This study evaluated the trabecular microarchitecture of lumbar spine using MDCT and C-arm CT in a series of young adult patients with anorexia nervosa (AN). 11 young females with AN underwent MDCT (anisotropic resolution with a slice thickness of ~626 μm) and C-arm CT (isotropic resolution of ~200 µm). Standard histomorphometric parameters the of L1 vertebral body, namely the apparent trabecular bone volume fraction (BV/TV), trabecular thickness (TbTh), trabecular number (TbN) and trabecular separation (TbSp), were analysed using MicroView software (GE Healthcare, Piscataway, NJ). Bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry. Trabecular parameters derived from MDCT and C-arm CT were compared, and their association with BMD parameters was evaluated. Histomorphometric parameters derived from C-arm CT, namely TbTh, TbN and TbSp, were significantly different from the corresponding MDCT parameters. There were no significant correlations between C-arm CT-derived parameters and the corresponding MDCT-derived parameters. C-arm CT-derived parameters were significantly (p<0.001) correlated with anteroposterior L1 spine BMD and Z-scores: TbTh (r=0.723, r=0.744, respectively), TbN (r=-0.720, r=-0.712, respectively) and TbSp (r=0.656, r=0.648, respectively). BV/TV, derived from C-arm CT, was significantly associated with body mass index (r=0.636) and ideal body weight (r=0.730) (p<0.05). These associations were not present in MDCT-derived parameters. This study suggests that the spatial resolution offered by C-arm CT more accurately captures the histomorphometric parameters of trabecular morphology than MDCT in patients with AN.

  15. Multidetector computed tomography evaluation of cavernous haemangioma of the azygous vein

    PubMed Central

    Das, Karuna Moy; Ahmed, Ali M.; Aljubab, Abdulwahab; Alzoum, Mohammed A.

    2013-01-01

    Giant cavernous haemangioma of azygous arch is extremely rare. We present the multidetector computed tomography (MDCT) features of a mediastinal cavernous haemangioma in an asymptomatic child detected in a follow-up examination. MDCT features with multiple venous lakes filling from the periphery, focal specks of calcification, low-density soft tissue mass along with tortuous varicose veins and large feeding veins from the abdomen are suggestive of cavernous haemangioma. PMID:23660735

  16. Multi-Detector Row Computed Tomographic Evaluation of a Rare Type of Complete Vascular Ring: Double Aortic Arch with Atretic Left Arch Distal to the Origin of Left Subclavian Artery

    PubMed Central

    Hung, Ying-Ying; Fu, Yun-Ching; Wei, Hao-Ji; Chen, Clayton Chi-Chang

    2013-01-01

    Double aortic arch with an atretic left arch distal to the origin of left subclavian artery was diagnosed with multi-detector row computed tomography (MDCT) in two children with dysphagia. This rare type of complete vascular ring is clinically important because it may be confused with right aortic arch in mirror imaging. Anatomic details of this rare type of complete vascular ring demonstrated on MDCT facilitated appropriate surgical treatment. PMID:24043984

  17. [X-ray diagnosis of retropatellar diseases (author's transl)].

    PubMed

    Wahlers, B

    1979-08-01

    The article reports on a comprehensive, stepwise diagnosis in diseases of the knee joints. This includes a description of the indication, the technique of taking x-ray films, and x-ray findings, as well as arthrography of the femoropatellar joint in retropatellar diseases such as chondropathia patellae, osteochondrosis dissecans, traumas of the knee joints and arthrosis deformans.

  18. Preoperative evaluation value of aortic arch lesions by multidetector computed tomography angiography in type A aortic dissection.

    PubMed

    Huang, Fang; Chen, Qiang; Lai, Qing-Quan; Huang, Wen-Han; Wu, Hong; Li, Wei-Cheng

    2016-09-01

    The purpose of this study was to preoperatively evaluate the value of aortic arch lesions by multidetector computed tomography (MDCT) angiography in type A aortic dissection (AD).From January 2013 to December 2015, we enrolled 42 patients with type A AD who underwent MDCT angiography in our hospital. The institutional database of patients was retrospectively reviewed to identify MDCT angiography examinations for type A AD. Surgical corrections were conducted in all patients to confirm diagnostic accuracy.In this study, the diagnostic accuracy of MDCT angiography was 100% in all 42 patients. The intimal tear site locations that were identified in patients included the ascending aorta (n = 25), aortic arch (n = 12), and all other sites (n = 5). Compared with the control group, there were significant differences in the aortic arch anatomy among the cases. Regarding the distance between the left common carotid and left subclavian arteries, compared with the control group, most cases with type A AD had a significant variation.MDCT angiography plays an important role in detecting aortic arch lesions of type A AD, especially in determining the location of the intimal entry site and change of branch blood vessels. Surgeons can formulate an appropriate operating plan, according to the preoperative MDCT diagnosis information. PMID:27684852

  19. Value and Accuracy of Multidetector Computed Tomography in Obstructive Jaundice

    PubMed Central

    Mathew, Rishi Philip; Moorkath, Abdunnisar; Basti, Ram Shenoy; Suresh, Hadihally B.

    2016-01-01

    Summary Background Objective; To find out the role of MDCT in the evaluation of obstructive jaundice with respect to the cause and level of the obstruction, and its accuracy. To identify the advantages of MDCT with respect to other imaging modalities. To correlate MDCT findings with histopathology/surgical findings/Endoscopic Retrograde CholangioPancreatography (ERCP) findings as applicable. Material/Methods This was a prospective study conducted over a period of one year from August 2014 to August 2015. Data were collected from 50 patients with clinically suspected obstructive jaundice. CT findings were correlated with histopathology/surgical findings/ERCP findings as applicable. Results Among the 50 people studied, males and females were equal in number, and the majority belonged to the 41–60 year age group. The major cause for obstructive jaundice was choledocholithiasis. MDCT with reformatting techniques was very accurate in picking a mass as the cause for biliary obstruction and was able to differentiate a benign mass from a malignant one with high accuracy. There was 100% correlation between the CT diagnosis and the final diagnosis regarding the level and type of obstruction. MDCT was able to determine the cause of obstruction with an accuracy of 96%. Conclusions MDCT with good reformatting techniques has excellent accuracy in the evaluation of obstructive jaundice with regards to the level and cause of obstruction. PMID:27429673

  20. Significant reduction of left atrial volume concomitant with clinical improvement after percutaneous transluminal septal myocardial ablation for drug-refractory hypertrophic obstructive cardiomyopathy, and its precise detection with multidetector CT

    PubMed Central

    Maekawa, Yuichiro; Akita, Keitaro; Tsuruta, Hikaru; Yamada, Yoshitake; Hayashida, Kentaro; Yuasa, Shinsuke; Murata, Mitsushige; Jinzaki, Masahiro; Fukuda, Keiichi

    2016-01-01

    Objective In patients with hypertrophic obstructive cardiomyopathy (HOCM), left atrial (LA) volume measurement is very important to provide prognostic information. Recent studies demonstrated that multidetector CT (MDCT) is useful to assess the changes in LA volume. Our aim was to examine the utility of a follow-up cardiac MDCT for long-term evaluation of the effect of percutaneous transluminal septal myocardial ablation (PTSMA) on LA volume. Methods We studied a consecutive cohort of 20 patients with drug-refractory symptomatic HOCM after PTSMA. We evaluated LA volume analyses with cardiac MDCT on patients who underwent PTSMA as compared to echocardiography. Results Before PTSMA, 75% of all patients had heart failure-associated symptoms in the New York Heart Association functional class III/IV. All patients experienced relief from heart failure-associated symptoms after PTSMA. Cardiac MDCT showed significant reduction in the index of maximum LA volume during follow-up compared to before PTSMA in the same way as in echocardiography (93.6±34.1 mL/m2 vs 82.6±35.3 mL/m2, p=0.035). A Bland-Altman plot showed small mean differences and limits of agreement in the measurements of the index of maximum LA volume before and after PTSMA between echocardiography and MDCT. Conclusions The follow-up cardiac MDCT was a useful tool to evaluate the effectiveness of PTSMA on reduction of LA volume. Cardiac MDCT might provide comparable measurements of the LA volume in patients with drug-refractory symptomatic HOCM before and after PTSMA compared to echocardiography. PMID:27307994

  1. Acute pulmonary embolism in the era of multi-detector CT: a reality in sub-Saharan Africa

    PubMed Central

    2012-01-01

    Background The advantages of multi-detector computed tomography (MDCT) have made it the imaging modality of choice for some patients with suspected cardiothoracic disease, of which pulmonary embolism (PE) is an exponent. The aim of this study was to assess the incidence of PE in patients with clinical suspicion of acute PE using MDCT in a sub-Saharan setting, and to describe the demographic characteristics of these patients. Methods Consecutive records of patients who underwent MDCT pulmonary angiography for suspected acute PE over a two-year period at the Radiology Department of a university-affiliated hospital were systematically reviewed. All MDCT pulmonary angiograms were performed with a 16-detector computed tomography (CT) scanner using real-time bolus tracking technique. Authorization for the study was obtained from the institutional authorities. Results Forty-one MDCT pulmonary angiograms were reviewed of which 37 were retained. Of the 4 excluded studies, 3 were repeat angiograms and 1 study was not technically adequate. Twelve of 37 patients (32.4%) had CT angiograms that were positive for PE, of which 7 were males. The mean age of these patients was 47.6±10.5 years (age range from 33 to 65 years). Twenty five patients out of 37 (67.6%) had CT angiograms that were negative for PE. Eleven PE-positive patients (91.7%) had at least 1 identifiable thromboembolic risk factor whilst 5 PE-negative patients (20%) also had at least a thromboembolic risk factor. The relative risk of the occurrence of PE in patients with at least a thromboembolic risk factor was estimated at 14.4. Conclusion Acute PE is a reality in sub-Saharan Africa, with an increased likelihood of MDCT evidence in patients with clinical suspicion of PE who have at least a thromboembolic risk factor. The increasing availability of MDCT will help provide more information on the occurrence of PE in these settings. PMID:23072500

  2. Comparison of Multidetector Computed Tomography and Flat-Panel Computed Tomography Regarding Visualization of Cortical Fractures, Cortical Defects, and Orthopedic Screws: A Phantom Study.

    PubMed

    Neubauer, Jakob; Benndorf, Matthias; Lang, Hannah; Lampert, Florian; Kemna, Lars; Konstantinidis, Lukas; Neubauer, Claudia; Reising, Kilian; Zajonc, Horst; Kotter, Elmar; Langer, Mathias; Goerke, Sebastian M

    2015-08-01

    To compare the visualization of cortical fractures, cortical defects, and orthopedic screws in a dedicated extremity flat-panel computed tomography (FPCT) scanner and a multidetector computed tomography (MDCT) scanner.We used feet of European roe deer as phantoms for cortical fractures, cortical defects, and implanted orthopedic screws. FPCT and MDCT scans were performed with equivalent dose settings. Six observers rated the scans according to number of fragments, size of defects, size of defects opposite orthopedic screws, and the length of different screws. The image quality regarding depiction of the cortical bone was assessed. The gold standard (real number of fragments) was evaluated by autopsy.The correlation of reader assessment of fragments, cortical defects, and screws with the gold standard was similar for FPCT and MDCT. Three readers rated the subjective image quality of the MDCT to be higher, whereas the others showed no preferences.Although the image quality was rated higher in the MDCT than in the FPCT by 3 out of 6 observers, both modalities proved to be comparable regarding the visualization of cortical fractures, cortical defects, and orthopedic screws and of use to musculoskeletal radiology regarding fracture detection and postsurgical evaluation in our experimental setting. PMID:26252281

  3. Evaluation of cardiovascular anomalies in patients with asymptomatic turner syndrome using multidetector computed tomography.

    PubMed

    Lee, Sun Hee; Jung, Ji Mi; Song, Min Seob; Choi, Seok jin; Chung, Woo Yeong

    2013-08-01

    Turner syndrome is well known to be associated with significant cardiovascular abnormalities. This paper studied the incidence of cardiovascular abnormalities in asymptomatic adolescent patients with Turner syndrome using multidetector computed tomography (MDCT) instead of echocardiography. Twenty subjects diagnosed with Turner syndrome who had no cardiac symptoms were included. Blood pressure and electrocardiography (ECG) was checked. Cardiovascular abnormalities were checked by MDCT. According to the ECG results, 11 had a prolonged QTc interval, 5 had a posterior fascicular block, 3 had a ventricular conduction disorder. MDCT revealed vascular abnormalities in 13 patients (65%). Three patients had an aberrant right subclavian artery, 2 had dilatation of left subclavian artery, and others had an aortic root dilatation, aortic diverticulum, and abnormal left vertebral artery. As for venous abnormalities, 3 patients had partial anomalous pulmonary venous return and 2 had a persistent left superior vena cava. This study found cardiovascular abnormalities in 65% of asymptomatic Turner syndrome patients using MDCT. Even though, there are no cardiac symptoms in Turner syndrome patients, a complete evaluation of the heart with echocardiography or MDCT at transition period to adults must be performed.

  4. Prevalence of extracardiac findings in the evaluation of ischemic heart disease by multidetector computed tomography

    PubMed Central

    Cho, Jeong-Hwan; Park, Jong-Seon; Shin, Dong-Gu; Kim, Young-Jo; Lee, Sang-Hee; Choi, Yoon-Jung; Cho, Ihn-Ho

    2013-01-01

    Objective Multidector computed tomography (MDCT) is now commonly used for the evaluation of coronary artery disease. Because MDCT images include many non-cardiac organs and the patient population evaluated is highly susceptible to extracardiac diseases, this study was designed to evaluate the prevalence of extracardiac findings in the MDCT evaluation of ischemic heart disease. Methods From March 2007 to March 2008, a total of six-hundred twenty patients, who underwent 64-slice MDCT evaluations for chest pain, or dyspnea, were enrolled in this study. Cardiac and non-cardiac findings were comprehensively evaluated by a radiologist. Results Enrolled patients included 306 men (49.4%), with a mean age of 66 years. Significant coronary artery stenosis was found in 41.6% of the patients. A total of 158 extracardiac findings were observed in 110 (17.7%) patients. Commonly involved extracardiac organs were lung (36.7%), hepatobiliary system (21.5%), thyroid (19.6%), kidney (10.8%), spine (9.7%) and breast (0.6%). Of those 110 patients, 50 (45.5%) patients underwent further diagnostic investigations. Malignant disease was detected in three (2.7%) patients (lung cancer, pancreatic cancer, and thyroid cancer). Conclusions Extracardiac findings are frequently present and should be a concern in the MDCT evaluation of chest pain syndrome. PMID:24133511

  5. Split-Bolus Multidetector-Row Computed Tomography Technique for Characterization of Focal Liver Lesions in Oncologic Patients

    PubMed Central

    Scialpi, Michele; Pierotti, Luisa; Gravante, Sabrina; Rebonato, Alberto; Piscioli, Irene; D’Andrea, Alfredo; Schiavone, Raffaele; Palumbo, Barbara

    2016-01-01

    Background In oncologic patients, the liver is the most common target for metastases. An accurate detection and characterization of focal liver lesions in patients with known primary extrahepatic malignancy are essential to define management and prognosis. Objectives To assess the diagnostic accuracy of the split-bolus multidetector-row computed tomography (MDCT) protocol in the characterization of focal liver lesions in oncologic patients. Patients and Methods We retrospectively analyzed the follow-up split-bolus 64-detector row CT protocol in 36 oncologic patients to characterize focal liver lesions. The split-bolus MDCT protocol by intravenous injection of two boluses of contrast medium combines the hepatic arterial phase (HAP) and hepatic enhancement during the portal venous phase (PVP) in a single-pass. Results The split-bolus MDCT protocol detected 208 lesions and characterized 186 (89.4%) of them: typical hemangiomas (n = 9), atypical hemangiomas (n = 3), cysts (n = 78), hypovascular (n = 93) and hypervascular (n = 3) metastases. Twenty two (10.6%) hypodense lesions were categorized as indeterminate (≤5 mm). The mean radiation dose was 24.5±6.5 millisieverts (mSv). Conclusion The designed split-bolus MDCT technique can be proposed alternatively to triphasic MDCT and in a single-pass to PVP in the initial staging and in the follow-up respectively in oncologic patients.

  6. Comparison of Multidetector Computed Tomography and Flat-Panel Computed Tomography Regarding Visualization of Cortical Fractures, Cortical Defects, and Orthopedic Screws

    PubMed Central

    Neubauer, Jakob; Benndorf, Matthias; Lang, Hannah; Lampert, Florian; Kemna, Lars; Konstantinidis, Lukas; Neubauer, Claudia; Reising, Kilian; Zajonc, Horst; Kotter, Elmar; Langer, Mathias; Goerke, Sebastian M.

    2015-01-01

    Abstract To compare the visualization of cortical fractures, cortical defects, and orthopedic screws in a dedicated extremity flat-panel computed tomography (FPCT) scanner and a multidetector computed tomography (MDCT) scanner. We used feet of European roe deer as phantoms for cortical fractures, cortical defects, and implanted orthopedic screws. FPCT and MDCT scans were performed with equivalent dose settings. Six observers rated the scans according to number of fragments, size of defects, size of defects opposite orthopedic screws, and the length of different screws. The image quality regarding depiction of the cortical bone was assessed. The gold standard (real number of fragments) was evaluated by autopsy. The correlation of reader assessment of fragments, cortical defects, and screws with the gold standard was similar for FPCT and MDCT. Three readers rated the subjective image quality of the MDCT to be higher, whereas the others showed no preferences. Although the image quality was rated higher in the MDCT than in the FPCT by 3 out of 6 observers, both modalities proved to be comparable regarding the visualization of cortical fractures, cortical defects, and orthopedic screws and of use to musculoskeletal radiology regarding fracture detection and postsurgical evaluation in our experimental setting. PMID:26252281

  7. Evaluation of Cardiovascular Anomalies in Patients with Asymptomatic Turner Syndrome Using Multidetector Computed Tomography

    PubMed Central

    Lee, Sun Hee; Jung, Ji Mi; Song, Min Seob; Choi, Seok jin

    2013-01-01

    Turner syndrome is well known to be associated with significant cardiovascular abnormalities. This paper studied the incidence of cardiovascular abnormalities in asymptomatic adolescent patients with Turner syndrome using multidetector computed tomography (MDCT) instead of echocardiography. Twenty subjects diagnosed with Turner syndrome who had no cardiac symptoms were included. Blood pressure and electrocardiography (ECG) was checked. Cardiovascular abnormalities were checked by MDCT. According to the ECG results, 11 had a prolonged QTc interval, 5 had a posterior fascicular block, 3 had a ventricular conduction disorder. MDCT revealed vascular abnormalities in 13 patients (65%). Three patients had an aberrant right subclavian artery, 2 had dilatation of left subclavian artery, and others had an aortic root dilatation, aortic diverticulum, and abnormal left vertebral artery. As for venous abnormalities, 3 patients had partial anomalous pulmonary venous return and 2 had a persistent left superior vena cava. This study found cardiovascular abnormalities in 65% of asymptomatic Turner syndrome patients using MDCT. Even though, there are no cardiac symptoms in Turner syndrome patients, a complete evaluation of the heart with echocardiography or MDCT at transition period to adults must be performed. PMID:23960443

  8. Diagnostic capability of gadoxetate disodium-enhanced liver MRI for diagnosis of hepatocellular carcinoma: comparison with multi-detector CT.

    PubMed

    Toyota, Naoyuki; Nakamura, Yuko; Hieda, Masashi; Akiyama, Naoko; Terada, Hiroaki; Matsuura, Noriaki; Nishiki, Masayo; Kono, Hirotaka; Kohno, Hiroshi; Irei, Toshimitsu; Yoshikawa, Yukinobu; Kuraoka, Kazuya; Taniyama, Kiyomi; Awai, Kazuo

    2013-09-01

    The purpose of this study was to evaluate the diagnostic capability of gadoxetate disodium (Gd-EOB)-MRI for the detection of hepatocellular carcinoma (HCC) compared with multidetector CT (MDCT). Fifty patients with 57 surgically proven HCCs who underwent Gd-EOB-MRI and MDCT from March 2008 to June 2011 were evaluated. Two observers evaluated MR and CT on a lesion-by-lesion basis. We analyzed sensitivity by grading on a 5-point scale, the degree of arterial enhancement and the differences in histological grades in the diffusion-weighted images (DWI). The results showed that the sensitivity of Gd-EOB-MRI was higher than that of MDCT especially for HCCs that were 1 cm in diameter or smaller. The hepatobiliary phase was useful for the detecting of small HCC. We had few cases in which it was difficult to judge HCC in the arterial enhancement between MRI and MDCT. In the diffusion-weighted image, well differentiated HCC tended to show a low signal intensity, and poorly differentiated HCC tended to show a high signal intensity. In moderately differentiated HCC's, the mean diameter of the high signal intensity group was larger than that of the low signal intensity group (24.5 mm vs. 15.8 mm). In conclusion, Gd-EOB-MRI tended to show higher sensitivity compared to MDCT in the detection of HCC.

  9. Hip Imaging in Athletes: Sports Imaging Series.

    PubMed

    Agten, Christoph A; Sutter, Reto; Buck, Florian M; Pfirrmann, Christian W A

    2016-08-01

    Hip or groin pain in athletes is common and clinical presentation is often nonspecific. Imaging is a very important diagnostic step in the work-up of athletes with hip pain. This review article provides an overview on hip biomechanics and discusses strategies for hip imaging modalities such as radiography, ultrasonography, computed tomography, and magnetic resonance (MR) imaging (MR arthrography and traction MR arthrography). The authors explain current concepts of femoroacetabular impingement and the problem of high prevalence of cam- and pincer-type morphology in asymptomatic persons. With the main focus on MR imaging, the authors present abnormalities of the hip joint and the surrounding soft tissues that can occur in athletes: intraarticular and extraarticular hip impingement syndromes, labral and cartilage disease, microinstability of the hip, myotendinous injuries, and athletic pubalgia. (©) RSNA, 2016. PMID:27429142

  10. Imaging of superior labral anterior to posterior (SLAP) tears of the shoulder.

    PubMed

    Simoni, P; Scarciolla, L; Kreutz, J; Meunier, B; Beomonte Zobel, B

    2012-12-01

    Superior labral anterior to posterior (SLAP) tears include a number of abnormal changes of the superior glenoid labrum. SLAP tears have been first reported in elite young atlete and are caused by repetitive overhead motion or by a fall on an outstretched arm. SLAP can lead to chronic pain and instability of shoulder. A diagnosis of SLAP may be difficult on the basis of clinical tests. Hence, modern imaging, including computed tomography arthrography (CTA), magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA) play a key role in the diagnosis of SLAP. The large number of normal anatomic variants of the superior labrum and the surrounding structures make the interpretation of SLAP challenging on imaging and at arthroscopy. In this article the imaging of SLAP are discussed in detail along with relevant anatomy, anatomic variants and biomechanics.

  11. Imaging in carpal instability.

    PubMed

    Ramamurthy, N K; Chojnowski, A J; Toms, A P

    2016-01-01

    Carpal instability is a complex and heterogeneous clinical condition. Management requires accurate identification of structural injury with an understanding of the resultant movement (kinematic) and load transfer (kinetic) failure. Static imaging techniques, such as plain film radiography, stress views, ultrasound, magnetic resonance, MR arthrography and computerized tomography arthrography, may accurately depict major wrist ligamentous injury. Dynamic ultrasound and videofluoroscopy may demonstrate dynamic instability and kinematic dysfunction. There is a growing evidence base for the diagnostic accuracy of these techniques in detecting intrinsic ligament tears, but there are limitations. Evidence of their efficacy and relevance in detection of non-dissociative carpal instability and extrinsic ligament tears is weak. Further research into the accuracy of existing imaging modalities is still required. Novel techniques, including four-dimensional computerized tomography and magnetic resonance, can evaluate both cross-sectional and functional carpal anatomy. This is a narrative review of level-III studies evaluating the role of imaging in carpal instability. PMID:26586689

  12. Arterial Tortuosity Syndrome: An Approach through Imaging Perspective.

    PubMed

    Bhat, Venkatraman

    2014-01-01

    This pictorial illustration demonstrates various aspects of arterial tortuosity syndrome (ATS) obtained predominantly from a multiple detector computed tomography (MDCT) examination of a patient. In addition, a comprehensive review of typical multi-modality imaging observations in patients with ATS is presented along with a description of a few imaging signs. Non-invasively obtained, conclusive information is required in patients with ATS in view of the fragile vascular structures involved. An amazing wealth of information can be obtained by reviewing the volumetric data sets of MDCT examination. In the context of incomplete clinical information or remote reading of radiographic examination with inadequate clinical details, ability to "image data mine" the hidden, unexplored information may be vastly useful. The role of MDCT as a single modality of evaluation in ATS is highlighted. PMID:25250193

  13. Assessment of coronary bypass graft patency by first-line multi-detector computed tomography.

    PubMed

    Pesenti-Rossi, D; Baron, N; Georges, J-L; Augusto, S; Gibault-Genty, G; Livarek, B

    2014-11-01

    The purpose of the study was to assess whether a strategy based on a MDCT performed routinely before CA can reduce the radiation dose during the CA, without increased global exposure in patients who need imaging of CABG. A total of 147 consecutive patients were included. The radiation dose during CA (KAP 12.1 vs 22.0 Gy/cm(2), P<.01) and the volume of iodinated contrast (155 vs 200 mL, P<.02) were reduced when preceded by a MDCT. Patients' cumulative exposures were not different in the 2 strategies (5.0 vs 5.1 mSv, P=.76). MDCT performed in first line is a valuable strategy for the assessment of CABG. PMID:25258019

  14. 3D segmentation and reconstruction of endobronchial ultrasound

    NASA Astrophysics Data System (ADS)

    Zang, Xiaonan; Breslav, Mikhail; Higgins, William E.

    2013-03-01

    State-of-the-art practice for lung-cancer staging bronchoscopy often draws upon a combination of endobronchial ultrasound (EBUS) and multidetector computed-tomography (MDCT) imaging. While EBUS offers real-time in vivo imaging of suspicious lesions and lymph nodes, its low signal-to-noise ratio and tendency to exhibit missing region-of-interest (ROI) boundaries complicate diagnostic tasks. Furthermore, past efforts did not incorporate automated analysis of EBUS images and a subsequent fusion of the EBUS and MDCT data. To address these issues, we propose near real-time automated methods for three-dimensional (3D) EBUS segmentation and reconstruction that generate a 3D ROI model along with ROI measurements. Results derived from phantom data and lung-cancer patients show the promise of the methods. In addition, we present a preliminary image-guided intervention (IGI) system example, whereby EBUS imagery is registered to a patient's MDCT chest scan.

  15. Three-dimensional reconstruction of New Zealand rabbit antebrachium by multidetector computed tomography

    PubMed Central

    Özkadif, S; Eken, E; Beşoluk, K; Dayan, M. O.

    2015-01-01

    The aim of this study was to reveal biometric peculiarities of New Zealand white rabbit antebrachium (radius and ulna) by means of three-dimensional (3D) reconstruction of multidetector computed tomography (MDCT) images. Under general anesthesia, the antebrachiums of a total of sixteen rabbits of both sexes were scanned with a general diagnostic MDCT. Biometric measurements of the reconstructed models from high resolution MDCT images were analyzed statistically. Consequently, when biometric measurement values of corresponding bones of antebrachium were compared, it was revealed that there was no statistical significance within both sexes but there were statistically important differences between both sexes in some biometric measurements. It has been suggested that the results from the study can shed light on future studies on the skeletal system and can form a modern point of view to anatomical education. PMID:27175177

  16. Diagnosis and management of hemoptysis

    PubMed Central

    Larici, Anna Rita; Franchi, Paola; Occhipinti, Mariaelena; Contegiacomo, Andrea; del Ciello, Annemilia; Calandriello, Lucio; Storto, Maria Luigia; Marano, Riccardo; Bonomo, Lorenzo

    2014-01-01

    Hemoptysis is the expectoration of blood that originates from the lower respiratory tract. It is usually a self-limiting event but in fewer than 5% of cases it may be massive, representing a life-threatening condition that warrants urgent investigations and treatment. This article aims to provide a comprehensive literature review on hemoptysis, analyzing its causes and pathophysiologic mechanisms, and providing details about anatomy and imaging of systemic bronchial and nonbronchial arteries responsible for hemoptysis. Strengths and limits of chest radiography, bronchoscopy, multidetector computed tomography (MDCT), MDCT angiography and digital subtraction angiography to assess the cause and lead the treatment of hemoptysis were reported, with particular emphasis on MDCT angiography. Treatment options for recurrent or massive hemoptysis were summarized, highlighting the predominant role of bronchial artery embolization. Finally, a guide was proposed for managing massive and non-massive hemoptysis, according to the most recent medical literature. PMID:24808437

  17. Multidetector CT in emergency radiology: acute and generalized non-traumatic abdominal pain.

    PubMed

    Paolantonio, Pasquale; Rengo, Marco; Ferrari, Riccardo; Laghi, Andrea

    2016-01-01

    Multidetector CT (MDCT) is an imaging technique that provides otherwise unobtainable information in the diagnostic work-up of patients presenting with acute abdominal pain. A correct working diagnosis depends essentially on understanding the individual patient's clinical data and laboratory findings. In haemodynamically stable patients with acute severe and generalized abdominal pain, MDCT is now the preferred imaging test and gives invaluable diagnostic information, also in unstable patients after stabilization. In this descriptive review, we focus our attention on acute, severe and generalized or undifferentiated non-traumatic abdominal pain. The main differential diagnoses are acute pancreatitis, gastrointestinal perforation, ruptured abdominal aneurysm and acute mesenteric ischaemia. We will provide radiologist readers with a technical guide to optimize MDCT imaging protocols and list the major CT signs essential to reach a correct diagnosis and guide the best treatment. PMID:26689097

  18. Candida prosthetic valve endocarditis: the complementary role of multidetector computed tomography and transoesophageal echocardiography in preoperative evaluation.

    PubMed

    Ghersin, E; Lessick, J; Agmon, Y; Engel, A; Kophit, A; Adler, Z

    2007-12-01

    A 72-year-old man with previous mitral valve replacement and single coronary bypass surgery was diagnosed with recurrent candida endocarditis by transoesophageal echocardiography and positive blood cultures. Preoperative electrocardiogram-gated multidetector CT (MDCT) was ordered to evaluate the patency and course of the mammary graft. In addition to verifying graft patency, MDCT demonstrated a mobile vegetation on the mitral prosthesis as well as a vegetation on the posterior left atrial wall which was not visible by transoesophageal echocardiography. Multidetector CT also revealed signs of osteomyelitis in the thoracic spine. Repeated surgery confirmed these findings and mitral valve replacement with resection of the left atrial vegetation were performed. This case illustrates the complementary role of MDCT and echocardiography in the preoperative evaluation of fungal endocarditis.

  19. Usefulness and limitations of postmortem computed tomography in forensic analysis of gunshot injuries: Three case reports.

    PubMed

    Usui, Akihito; Kawasumi, Yusuke; Hosokai, Yoshiyuki; Kozakai, Masataka; Saito, Haruo; Funayama, Masato

    2016-01-01

    Gunshot injury has always been an important field of investigation in postmortem forensic radiology. The localization and retrieval of the bullet and of potentially important fragments are vital to these cases. Using postmortem multidetector-row computed tomography (MDCT) prior to forensic autopsy, we sought to illustrate the importance of this modality in the noninvasive characterization of gunshot wounds. We obtained and analyzed MDCT images in three cases of gunshot wounds (accidental close-range shotgun shooting, suicidal contact gunshot to the head and accidental long-range buckshot shooting). We discuss the value of postmortem MDCT findings in gunshot wound cases by comparing with forensic autopsy findings in Japan, a developing country with miserably low autopsy rate. PMID:26832386

  20. Arterial Tortuosity Syndrome: An Approach through Imaging Perspective

    PubMed Central

    Bhat, Venkatraman

    2014-01-01

    This pictorial illustration demonstrates various aspects of arterial tortuosity syndrome (ATS) obtained predominantly from a multiple detector computed tomography (MDCT) examination of a patient. In addition, a comprehensive review of typical multi-modality imaging observations in patients with ATS is presented along with a description of a few imaging signs. Non-invasively obtained, conclusive information is required in patients with ATS in view of the fragile vascular structures involved. An amazing wealth of information can be obtained by reviewing the volumetric data sets of MDCT examination. In the context of incomplete clinical information or remote reading of radiographic examination with inadequate clinical details, ability to “image data mine” the hidden, unexplored information may be vastly useful. The role of MDCT as a single modality of evaluation in ATS is highlighted. PMID:25250193

  1. Multidetector CT of hepatic artery pathologies.

    PubMed

    Karaosmanoglu, D; Erol, B; Karcaaltincaba, M

    2012-01-01

    The hepatic artery can be involved by a variety of pathology and diseases.Today MDCT enables high quality imaging of the hepatic artery using axial, MIP and volume rendered images. We illustrate MDCT findings of anatomical variations, aneurysm, dilatation, dissection, arteriovenous fistula, thrombosis and stenosis. Aneurysms can be saccular, fusiform and multiple and may develop due to atherosclerosis, vasculitis, trauma and biopsy. Dilatation of hepatic artery can be seen in portal hypertension, Osler-Weber-Rendu disease and hemangiomatosis. Hepatic artery can be occluded after trauma and transplantation. Dissection develops due to atherosclerosis, Marfan and Ehler Danlos syndromes and during pregnancy. Arteriovenous fistula can be congenital and acquired. We conclude that various hepatic artery pathologies can be confidently diagnosed by MDCT.

  2. Imaging of the aortic valve with MRI and CT angiography.

    PubMed

    Harvey, J J; Hoey, E T D; Ganeshan, A

    2013-12-01

    The aortic valve may be affected by a wide range of congenital and acquired diseases. Echocardiography is the main non-invasive imaging technique for assessing patho-anatomical alterations of the aortic valve and adjacent structures and in many cases is sufficient to establish a diagnosis and/or guide treatment decisions. Recent technological advances in magnetic resonance imaging (MRI) and multidetector computed tomography (MDCT) have enabled these techniques to play a complimentary role in certain clinical scenarios and as such can be useful problem-solving tools. Radiologists should be familiar with the indications, advantages, and limitations of MRI and MDCT in order to advise and direct an appropriate imaging strategy depending upon the clinical scenario. This article reviews the role of MRI and MDCT angiography for assessment of the aortic valve including relevant anatomy, scan acquisition protocols, and post-processing methods. An approach to interpretation and the key imaging features of commonly encountered aortic valvular diseases are discussed.

  3. Bipartite patella causing knee pain in young adults: a report of 5 cases.

    PubMed

    Vaishya, Raju; Chopra, Surender; Vijay, Vipul; Vaish, Abhishek

    2015-04-01

    We report on 5 patients who underwent arthroscopic excision or open reduction and internal fixation for bipartite patella. All patients presented with refractory anterior knee pain. The diagnosis of bipartite patella was made using radiography, and confirmed with magnetic resonance imaging or computed tomographic arthrography. All 5 patients achieved complete resolution of symptoms after surgery, and remained pain-free after a mean followup period of 13 months. PMID:25920661

  4. Throwing injuries of the upper extremity.

    PubMed

    Patel, Neel B; Thomas, Stephen; Lazarus, Martin L

    2013-03-01

    The overhead throwing motion is a complex sequence of maneuvers that requires coordinated muscle activity in the upper and lower extremities. The shoulder and elbow are subject to multidirectional forces and are particularly vulnerable to injury during specific phases of the overhead throwing motion. Ligamentous, tendinous, neural, and osseous pathology that may occur in the shoulder or elbow of an overhead-throwing athlete will be discussed, with an emphasis on the role of MR imaging and MR arthrography.

  5. Potential of incorporated accelerometers for the in vivo assessment of hip stem loosening

    NASA Astrophysics Data System (ADS)

    Lowet, G.; Van der Perre, G.

    1994-09-01

    The detection of prosthesis loosening in total hip replacement remains a problematic issue. Common techniques such as radiography and arthrography have not been shown to be very effective. Although originally developed for the assessment of fracture healing, vibration analysis was proposed as a method for the detection of loose prostheses [1,2]. In this paper, we will discuss the principles used in the vibration analysis in relation with the detection of loose prothesis and discuss the potential and limitations.

  6. Optimal procedure planning and guidance system for peripheral bronchoscopy.

    PubMed

    Gibbs, Jason D; Graham, Michael W; Bascom, Rebecca; Cornish, Duane C; Khare, Rahul; Higgins, William E

    2014-03-01

    With the development of multidetector computed-tomography (MDCT) scanners and ultrathin bronchoscopes, the use of bronchoscopy for diagnosing peripheral lung-cancer nodules is becoming a viable option. The work flow for assessing lung cancer consists of two phases: 1) 3-D MDCT analysis and 2) live bronchoscopy. Unfortunately, the yield rates for peripheral bronchoscopy have been reported to be as low as 14%, and bronchoscopy performance varies considerably between physicians. Recently, proposed image-guided systems have shown promise for assisting with peripheral bronchoscopy. Yet, MDCT-based route planning to target sites has relied on tedious error-prone techniques. In addition, route planning tends not to incorporate known anatomical, device, and procedural constraints that impact a feasible route. Finally, existing systems do not effectively integrate MDCT-derived route information into the live guidance process. We propose a system that incorporates an automatic optimal route-planning method, which integrates known route constraints. Furthermore, our system offers a natural translation of the MDCT-based route plan into the live guidance strategy via MDCT/video data fusion. An image-based study demonstrates the route-planning method's functionality. Next, we present a prospective lung-cancer patient study in which our system achieved a successful navigation rate of 91% to target sites. Furthermore, when compared to a competing commercial system, our system enabled bronchoscopy over two airways deeper into the airway-tree periphery with a sample time that was nearly 2 min shorter on average. Finally, our system's ability to almost perfectly predict the depth of a bronchoscope's navigable route in advance represents a substantial benefit of optimal route planning.

  7. Multidetector computer tomography: evaluation of blunt chest trauma in adults.

    PubMed

    Palas, João; Matos, António P; Mascarenhas, Vasco; Herédia, Vasco; Ramalho, Miguel

    2014-01-01

    Imaging plays an essential part of chest trauma care. By definition, the employed imaging technique in the emergency setting should reach the correct diagnosis as fast as possible. In severe chest blunt trauma, multidetector computer tomography (MDCT) has become part of the initial workup, mainly due to its high sensitivity and diagnostic accuracy of the technique for the detection and characterization of thoracic injuries and also due to its wide availability in tertiary care centers. The aim of this paper is to review and illustrate a spectrum of characteristic MDCT findings of blunt traumatic injuries of the chest including the lungs, mediastinum, pleural space, and chest wall. PMID:25295188

  8. Chest wall, lung, and pleural space trauma.

    PubMed

    Miller, Lisa A

    2006-03-01

    Chest radiographs frequently underestimate the severity and extent of chest trauma and, in some cases, fail to detect the presence of injury. CT is more sensitive than chest radiography in the detection of pulmonary, pleural, and osseous abnormalities in the patient who has chest trauma. With the advent of multidetector CT (MDCT), high-quality multiplanar reformations are obtained easily and add to the diagnostic capabilities of MDCT. This article reviews the radiographic and CT findings of chest wall, pleural, and pulmonary injuries that are seen in the patient who has experienced blunt thoracic trauma.

  9. Non-invasive assessment of coronary artery bypass graft with retrospectively ECG-gated four-row multi-detector spiral computed tomography.

    PubMed

    Marano, Riccardo; Storto, Maria Luigia; Maddestra, Nicola; Bonomo, Lorenzo

    2004-08-01

    The purpose of this study was to assess the accuracy of four-row multi-detector CT (MDCT) in the evaluation of coronary artery bypass graft (CABG) in patients with at least a left internal mammary artery (LIMA) grafted to the left anterior descending artery (LAD), because of the conduit of choice in bypass surgery and the greater difficulty of evaluation with non-invasive diagnostic tools. Included in the study were 57 patients with a total of 122 grafts (95 arterial and 27 venous) who underwent MDCT (4x2.5-mm detector-collimation, 3-mm slice width, 1.5-mm reconstruction increment) with retrospective ECG gating. Twelve patients (21%) with high heart rates were given beta-blockers in order to obtain a heart rate MDCT correctly classified 92/94 patent grafts and 26/28 occluded grafts (sensitivity/specificity 93%/97.8%); sensitivity and specificity of MDCT for assessment of arterial grafts were 100 and 98.7% (77/78 patent grafts and 17/17 occluded grafts). Image quality was considered adequate for assessment of significant stenoses in 62/92 (67%) patent grafts, with a significant differences between LIMA and non-LIMA conduits (44/57 vs. 18/65; P=0.002), according to the coronary vessel area supplied (anterior>lateral>posterior-inferior wall; P=0.002). In the remaining 30 patent grafts (33%), the assessment of stenoses was hampered by surgical clips, calcifications and motion artifacts. Sensitivity and specificity of MDCT for detection of significant graft stenoses were 80 and 96%, respectively. Inter-observer agreement was good ( K=0.73). MDCT seems to be a valuable diagnostic tool for non-invasive assessment of patency of both venous and arterial grafts. An accurate evaluation

  10. Identification of Cardiac and Aortic Injuries in Trauma with Multi-detector Computed Tomography

    PubMed Central

    Shergill, Arvind K; Maraj, Tishan; Barszczyk, Mark S; Cheung, Helen; Singh, Navneet; Zavodni, Anna E

    2015-01-01

    Blunt and penetrating cardiovascular (CV) injuries are associated with a high morbidity and mortality. Rapid detection of these injuries in trauma is critical for patient survival. The advent of multi-detector computed tomography (MDCT) has led to increased detection of CV injuries during rapid comprehensive scanning of stabilized major trauma patients. MDCT has the ability to acquire images with a higher temporal and spatial resolution, as well as the capability to create multiplanar reformats. This pictorial review illustrates several common and life-threatening traumatic CV injuries from a regional trauma center. PMID:26430541

  11. [Capabilities of Multidetector Computed Tomography in Assessment of Atherosclerosis of Coronary Arteries].

    PubMed

    Barysheva, N A; Merkulova, I N; Sharia, M A; Veselova, T N

    2015-01-01

    The prevalence of ischemic heart disease (IHD) as well as high mortality from its exacerbations led to an active search and study of diagnostic methods to predict the possible development of acute coronary events. At the moment, it is proved that the morphological properties of atherosclerotic plaque largely determine the course of IHD. Contemporary multidetector computed tomography (MDCT) is the only non-invasive method which allows to study the state of coronary arteries. In this review we have analyzed capabilities of MDCT in assessing the severity of stenosis and calcification in the coronary arteries, as well as the structure of atherosclerotic plaques, including signs of "instability".

  12. Post-processing and display in multislice CT of the chest.

    PubMed

    Beigelman-Aubry, C

    2007-01-01

    The last generations of Multi Detector Row CT (MDCT) have revolutionized the management of chest disease. This is especially obvious for airway and lung parenchyma evaluation. MDCT allows volumetric high resolution scanning with isotropic resolution. Thus, contiguous visualization of the lung parenchyma is achieved. The resulting high quality 2D and 3D reconstructions enable a significant improvement in the diagnostic approach. Since the lung parenchyma has a unique natural contrast, low and even ultra-low radiation dose scanning protocols may be used in routine practice. In all cases, a good signal to noise ratio has to be maintained combined with the best possible spatial resolution, allowing all types of reconstructions.

  13. Multidetector Computer Tomography: Evaluation of Blunt Chest Trauma in Adults

    PubMed Central

    Matos, António P.; Mascarenhas, Vasco; Herédia, Vasco

    2014-01-01

    Imaging plays an essential part of chest trauma care. By definition, the employed imaging technique in the emergency setting should reach the correct diagnosis as fast as possible. In severe chest blunt trauma, multidetector computer tomography (MDCT) has become part of the initial workup, mainly due to its high sensitivity and diagnostic accuracy of the technique for the detection and characterization of thoracic injuries and also due to its wide availability in tertiary care centers. The aim of this paper is to review and illustrate a spectrum of characteristic MDCT findings of blunt traumatic injuries of the chest including the lungs, mediastinum, pleural space, and chest wall. PMID:25295188

  14. Multidetector computer tomography: evaluation of blunt chest trauma in adults.

    PubMed

    Palas, João; Matos, António P; Mascarenhas, Vasco; Herédia, Vasco; Ramalho, Miguel

    2014-01-01

    Imaging plays an essential part of chest trauma care. By definition, the employed imaging technique in the emergency setting should reach the correct diagnosis as fast as possible. In severe chest blunt trauma, multidetector computer tomography (MDCT) has become part of the initial workup, mainly due to its high sensitivity and diagnostic accuracy of the technique for the detection and characterization of thoracic injuries and also due to its wide availability in tertiary care centers. The aim of this paper is to review and illustrate a spectrum of characteristic MDCT findings of blunt traumatic injuries of the chest including the lungs, mediastinum, pleural space, and chest wall.

  15. [Capabilities of Multidetector Computed Tomography in Assessment of Atherosclerosis of Coronary Arteries].

    PubMed

    Barysheva, N A; Merkulova, I N; Sharia, M A; Veselova, T N

    2015-01-01

    The prevalence of ischemic heart disease (IHD) as well as high mortality from its exacerbations led to an active search and study of diagnostic methods to predict the possible development of acute coronary events. At the moment, it is proved that the morphological properties of atherosclerotic plaque largely determine the course of IHD. Contemporary multidetector computed tomography (MDCT) is the only non-invasive method which allows to study the state of coronary arteries. In this review we have analyzed capabilities of MDCT in assessing the severity of stenosis and calcification in the coronary arteries, as well as the structure of atherosclerotic plaques, including signs of "instability". PMID:26502511

  16. Multidetector row computed tomography evaluation of the micropig kidney as a potential renal donor.

    PubMed

    Yoon, Woong; Lee, Min Young; Ryu, Jung Min; Moon, Yong Ju; Lee, Sang Hun; Park, Jae Hong; Yun, Seung Pil; Jang, Min Woo; Park, Sung Su; Han, Ho Jae

    2010-03-01

    Multidetector row computed tomography (MDCT) provides anatomical information about the kidney and other internal organs. Presently, the suitability of 64-channel MDCT to assess the kidney of healthy micropigs was evaluated. Morphological evaluations of the kidney and the major renal vessels of six healthy micropigs were carried out using MDCT, recording kidney volume and the diameter and length of renal arteries and veins. The mean diameters and lengths of the renal artery were 0.44 +/- 0.05 and 4.51 +/- 0.55 cm on the right side and 0.46 +/- 0.06 and 3.36 +/- 0.27 cm on the left side, respectively. The mean diameters and lengths of the renal vein were 1.44 +/- 0.52 and 4.22 +/- 1.29 cm on the right side and 1.38 +/- 0.17 and 5.15 +/- 0.87 cm on the left side, respectively. The mean volume of the right kidney was 79.3 +/- 14.5 mL and of the left kidney was 78.0 +/- 13.9 mL. The data presented in this study suggest that the MDCT offers a noninvasive, rapid, and accurate method for the evaluation of the renal anatomy in living kidney donors. It also provides sufficient information about extra-renal anatomy important for donor surgery and determination of organ suitability.

  17. The New Approach to Sport Medicine: 3-D Reconstruction

    ERIC Educational Resources Information Center

    Ince, Alparslan

    2015-01-01

    The aim of this study is to present a new approach to sport medicine. Comparative analysis of the Vertebrae Lumbales was done in sedentary group and Muay Thai athletes. It was done by acquiring three dimensional (3-D) data and models through photogrammetric methods from the Multi-detector Computerized Tomography (MDCT) images of the Vertebrae…

  18. Forensic imaging of projectiles using cone-beam computed tomography.

    PubMed

    von See, Constantin; Bormann, Kai-Hendrik; Schumann, Paul; Goetz, Friedrich; Gellrich, Nils-Claudius; Rücker, Martin

    2009-09-10

    In patients with gunshot injuries, it is easy to detect a projectile within the body due to the high-density of the object, but artefacts make it difficult to obtain information about the deformation and the exact location of the projectile in surrounding tissues. Cone-beam computed tomography (CBCT) is a new radiological imaging modality that allows radio-opaque objects to be localised and assessed in three dimensions. The full potential of the use of CBCT in forensic medicine has not yet been explored. In this study, three different modern projectiles were fired into the heads of pig cadavers (n=6) under standardised conditions. Tissue destruction and the location of the projectiles were analysed separately using CBCT and multi-slice computed tomography (MDCT). The projectiles had the same kinetic energy but showed considerable differences in deformation behaviour. Within the study groups, tissue destruction was reproducible. CBCT is less severely affected by metallic artefacts than MDCT. Therefore CBCT is superior in visualising bone destruction in the immediate vicinity of the projectile and projectile deformation, whereas MDCT allows soft tissue to be evaluated in more detail. CBCT is an improved diagnostic tool for the evaluation of gunshot injuries. In particular, it is superior to MDCT in detecting structural hard-tissue damage in the immediate vicinity of high-density metal projectiles and in identifying the precise location of a projectile in the body.

  19. [Characteristics of pneumoconiosis on multi-detector row CT and its' anatomic-pathologic basis].

    PubMed

    Feng, Yuanchun; Yang, Zhigang; Li, Yuan; Chen, Tianwu; Wang, Qiling; Deng, Wen

    2011-04-01

    In order to investigate the fine distinction of the tomographic images and the dominant anatomic distributions, we carefully reviewed and analyzed the features and predominant anatomic distribution of forty-nine pneumoconiosis patients with confirmed diagnosis on multi-detector row CT (MDCT). It was found that the round and small opacity p and irregular small opacity were mostly shown in the MDCT features of pneumoconiosis, while the large opacity and progressive massive fibrosis (PMF) were less frequently depicted in the MDCT. Distributions of round and small opacity and irregular small opacity in the six lung lobes were significantly different (P < 0.01). The most common p opacity was significantly seen in the upper and lower left lungs as well as in the upper right lung's opacity was in the upper left lung as well as lower left and right lungs. The large opacity commonly distributed in upper left and right lungs, while the PMF was often shown in both of two lungs. The results demonstrated that the MDCT could be an effective modality for detecting tiny lesions and anatomic distribution of pneumoconiosis, and it would be helpful for early diagnosis and accurate staging of the pneumoconiosis disease.

  20. [Application of computed tomography (CT) examination for forensic medicine].

    PubMed

    Urbanik, Andrzej; Chrzan, Robert

    2013-01-01

    The aim of the study is to present a own experiences in usage of post mortem CT examination for forensic medicine. With the help of 16-slice CT scanner 181 corpses were examined. Obtained during acquisition imaging data are later developed with dedicated programmes. Analyzed images were extracted from axial sections, multiplanar reconstructions as well as 3D reconstructions. Gained information helped greatly when classical autopsy was performed by making it more accurate. A CT scan images recorded digitally enable to evaluate corpses at any time, despite processes of putrefaction or cremation. If possible CT examination should precede classical autopsy.

  1. [Application of computed tomography (CT) examination for forensic medicine].

    PubMed

    Urbanik, Andrzej; Chrzan, Robert

    2013-01-01

    The aim of the study is to present a own experiences in usage of post mortem CT examination for forensic medicine. With the help of 16-slice CT scanner 181 corpses were examined. Obtained during acquisition imaging data are later developed with dedicated programmes. Analyzed images were extracted from axial sections, multiplanar reconstructions as well as 3D reconstructions. Gained information helped greatly when classical autopsy was performed by making it more accurate. A CT scan images recorded digitally enable to evaluate corpses at any time, despite processes of putrefaction or cremation. If possible CT examination should precede classical autopsy. PMID:23944089

  2. Multimodality 3D Tumor Segmentation in HCC patients treated with TACE

    PubMed Central

    Wang, Zhijun; Chapiro, Julius; Schernthaner, Rüdiger; Duran, Rafael; Chen, Rongxin; Geschwind, Jean-François; Lin, MingDe

    2015-01-01

    Rationale and Objectives To validate the concordance of a semi-automated multimodality lesion segmentation technique between contrast-enhanced MRI (CE-MRI), cone-beam CT (CBCT) and multi-detector CT (MDCT) in patients with hepatocellular carcinoma (HCC) treated with transarterial chemoembolization (TACE). Materials and methods This retrospective analysis included 45 patients with unresectable HCC that underwent baseline CE-MRI within one month before the treatment, intraprocedural CBCT during conventional TACE and MDCT within 24 hours post TACE. Fourteen patients were excluded due to atypical lesion morphology, portal vein invasion or small lesion size which precluded sufficient lesion visualization. 31 patients with a total of 40 target lesions were included into the analysis. A tumor segmentation software, based on non-Euclidean geometry and theory of radial basis functions, was used to allow for the segmentation of target lesions in 3D on all three modalities. The algorithm created image-based masks located in a 3D region whose center and size was defined by the user, yielding the nomenclature “semi-automatic”. Based on that, tumor volumes on all three modalities were calculated and compared using a linear regression model (R2 values). Residual plots were used to analyze drift and variance of the values. Results The mean value of tumor volumes was 18.72±19.13cm3 (range, 0.41-59.16cm3) on CE-MRI, 21.26±21.99 cm3 (range, 0.62-86.82 cm3) on CBCT and 19.88±20.88 cm3 (range, 0.45-75.24 cm3) on MDCT. The average volumes of the tumor were not significantly different between CE-MR and DP-CBCT, DP-CBCT and MDCT, MDCT and CE-MR (p=0.577, 0.770 and 0.794 respectively). A strong correlation between volumes on CE-MRI and CBCT, CBCT and MDCT, MDCT and CE-MRI was observed (R2=0.974, 0.992 and 0.983, respectively). When plotting the residuals, no drift was observed for all methods showing deviations of no more than 10% of absolute volumes (in cm3). Conclusion A semi

  3. National Survey of Radiation Dose and Image Quality in Adult CT Head Scans in Taiwan

    PubMed Central

    Lin, Chung-Jung; Mok, Greta S. P.; Tsai, Mang-Fen; Tsai, Wei-Ta; Yang, Bang-Hung; Tu, Chun-Yuan; Wu, Tung-Hsin

    2015-01-01

    Introduction The purpose of the present study was to evaluate the influence of different variables on radiation dose and image quality based on a national database. Materials and Methods Taiwan’s Ministry of Health and Welfare requested all radiology departments to complete a questionnaire for each of their CT scanners. Information gathered included all scanning parameters for CT head scans. For the present analysis, CT machines were divided into three subgroups: single slice CT (Group A); multi-detector CT (MDCT) with 2-64 slices (Group B); and MDCT with more than 64 slices (Group C). Correlations between computed tomography dose index (CTDI) and signal-to-noise ratio (SNR) with cumulated tube rotation number (CTW(n)) and cumulated tube rotation time (CTW(s)), and sub group analyses of CTDI and SNR across the three groups were performed. Results CTDI values demonstrated a weak correlation (r = 0.33) with CTW(n) in Group A. SNR values demonstrated a weak negative correlation (r = -0.46) with CTW(n) in Group C. MDCT with higher slice numbers used more tube potential resulting in higher effective doses. There were both significantly lower CTDI and SNR values in helical mode than in axial mode in Group B, but not Group C. Conclusion CTW(n) and CTW(s) did not influence radiation output. Helical mode is more often used in MDCT and results in both lower CTDI and SNR compared to axial mode in MDCT with less than 64 slices. PMID:26125549

  4. Comparison of Multidetector CT and Gadobutrol-Enhanced MR Imaging for Evaluation of Small, Solid Pancreatic Lesions

    PubMed Central

    Choi, Tae Won; Kim, Jung Hoon; Yu, Mi Hye; Han, Joon Koo; Choi, Byung Ihn

    2016-01-01

    Objective To compare multidetector computed tomography (MDCT) and MRI for lesion conspicuity, as well as the detection and characterization of small solid pancreatic lesions (SPLs). Materials and Methods 193 patients with small SPLs (< 3 cm) and 52 patients with normal pancreas who underwent both multiphasic MDCT and gadobutrol-enhanced MRI were included in our study. Two radiologists blinded to the pathologic diagnoses independently reviewed those images, and determined the detection of "SPL per se" and "SPL in consideration of secondary features", the lesion conspicuity, the probability of pancreatic ductal adenocarcinoma (PDAC), and the most likely specific diagnosis. Results The sensitivity of MRI for "detection of SPL per se" was significantly higher than that of CT in both reviewers: 92.7% (179/193) and 97.9% (189/193), respectively, for reviewer 1 (p = 0.031) and 90.7% (175/193) and 99.5% (192/193), respectively, for reviewer 2 (p < 0.001). In addition, MRI provided better lesion conspicuity than MDCT for both reviewers (p < 0.001). However, CT and MRI did not show significant difference in sensitivity for "detection of SPL in consideration of secondary features", specificity for SPL detection, and differentiation of PDAC vs. non-PDAC (p > 0.05). The accuracies of CT and MRI for making a specific diagnosis were as follows: 85.7% (210/245) vs. 86.9% (213/245), respectively, for reviewer 1 (p = 0.736), and 91.8% (225/245) vs. 93.5% (229/245), respectively, for reviewer 2 (p = 0.454). Conclusion MRI showed better lesion conspicuity than MDCT, but did not show significantly different diagnostic performance compared with MDCT for detecting and characterizing small SPLs. PMID:27390542

  5. Assessment of liver ablation using cone beam computed tomography

    PubMed Central

    Abdel-Rehim, Mohamed; Ronot, Maxime; Sibert, Annie; Vilgrain, Valérie

    2015-01-01

    AIM: To investigate the feasibility and accuracy of cone beam computed tomography (CBCT) in assessing the ablation zone after liver tumor ablation. METHODS: Twenty-three patients (17 men and 6 women, range: 45-85 years old, mean age 65 years) with malignant liver tumors underwent ultrasound-guided percutaneous tumor ablation [radiofrequency (n = 14), microwave (n = 9)] followed by intravenous contrast-enhanced CBCT. Baseline multidetector computed tomography (MDCT) and peri-procedural CBCT images were compared. CBCT image quality was assessed as poor, good, or excellent. Image fusion was performed to assess tumor coverage, and quality of fusion was rated as bad, good, or excellent. Ablation zone volumes on peri-procedural CBCT and post-procedural MDCT were compared using the non-parametric paired Wilcoxon t-test. RESULTS: Rate of primary ablation effectiveness was 100%. There were no complications related to ablation. Local tumor recurrence and new liver tumors were found 3 mo after initial treatment in one patient (4%). The ablation zone was identified in 21/23 (91.3%) patients on CBCT. The fusion of baseline MDCT and peri-procedural CBCT images was feasible in all patients and showed satisfactory tumor coverage (at least 5-mm margin). CBCT image quality was poor, good, and excellent in 2 (9%), 8 (35%), and 13 (56%), patients respectively. Registration quality between peri-procedural CBCT and post-procedural MDCT images was good to excellent in 17/23 (74%) patients. The median ablation volume on peri-procedural CBCT and post-procedural MDCT was 30 cm3 (range: 4-95 cm3) and 30 cm3 (range: 4-124 cm3), respectively (P-value > 0.2). There was a good correlation (r = 0.79) between the volumes of the two techniques. CONCLUSION: Contrast-enhanced CBCT after tumor ablation of the liver allows early assessment of the ablation zone. PMID:25593467

  6. Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid (Gd-EOB-DTPA)-Enhanced Magnetic Resonance Imaging and Multidetector-Row Computed Tomography for the Diagnosis of Hepatocellular Carcinoma

    PubMed Central

    Ye, Feng; Liu, Jun; Ouyang, Han

    2015-01-01

    Abstract The purpose of this meta-analysis was to compare the diagnostic accuracy of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and multidetector-row computed tomography (MDCT) for hepatocellular carcinoma (HCC). Medline, Cochrane, EMBASE, and Google Scholar databases were searched until July 4, 2014, using combinations of the following terms: gadoxetic acid disodium, Gd-EOB-DTPA, multidetector CT, contrast-enhanced computed tomography, and magnetic resonance imaging. Inclusion criteria were as follows: confirmed diagnosis of primary HCC by histopathological examination of a biopsy specimen; comparative study of MRI using Gd-EOB-DTPA and MDCT for diagnosis of HCC; and studies that provided quantitative outcome data. The pooled sensitivity and specificity of the 2 methods were compared, and diagnostic accuracy was assessed with alternative-free response receiver-operating characteristic analysis. Nine studies were included in the meta-analysis, and a total of 1439 lesions were examined. The pooled sensitivity and specificity for 1.5T MRI were 0.95 and 0.96, respectively, for 3.0T MRI were 0.91 and 0.96, respectively, and for MDCT were 0.74 and 0.93, respectively. The pooled diagnostic odds ratio for 1.5T and 3.0T MRI was 242.96, respectively, and that of MDCT was 33.47. To summarize, Gd-EOB-DTPA-enhanced MRI (1.5T and 3.0T) has better diagnostic accuracy for HCC than MDCT. PMID:26266348

  7. Simultaneous Tc-99m skeletal and In-111 hip arthrographic scintimaging complementing contrast radiography

    SciTech Connect

    Wellman, H.N.; Uri, B.G.; Stiner, P.; Mock, B.H.; Capello, W.

    1984-01-01

    Prosthetic hip replacement has become a frequent procedure with femoral component (FC) loosening occurring frequently at a rate of 24% at 7 yrs post arthroplasty. Pain may occur from a variety of causes and identification of loosening as the cause is critical. Experience with radiographic contrast arthrography (XA) alone has often resulted in equivocal studies because of confusion caused by the radio-opaque glue-bone interface and adjacent radiolucency of the FC. Radionuclide arthrography (RA) with Tc-99m Sulfur Colloid (SC) has been previously shown to improve the efficiency of FC loosening determination. However, with extravasation or other confusing patterns of tracer distribution more precise localization relative to skeletal structure is required with RA. Simultaneous use of RA using In-111 (IN) chloride (0.2 mCi) injected with contrast at XA superimposed on prior injected TC-99m MDP (20 mCi) skeletal imaging (SI) has considerably improved interpretation and complemented XA, correlated with surgery. Fifty RA and XA patients have been studied: 18 with SC alone, 7 with SC and IN in the joint space simultaneously and 25 with IN RA and SI. Simultaneous joint injection RA with IN and SC demonstrated exactly the same pattern with no translocation of IN. Thirty patients had surgery with 20 loose FC verified; all loose by RA but only 16 by XA plus 2 false positives. Also simultaneous SI has shown unreliable criteria for FC loosening. Thus, addition of simultaneous RA and SI for FC evaluation is a valuable adjunct in 20% of patients in the performance of arthrography.

  8. [Chondropathy of the patella. Experiences with 100 medializations].

    PubMed

    Villiger, K J

    1976-10-01

    After a brief reference to the biomechanics of the patellofemoral joint, the anamnesis and the clinical and the radiologic symptomatology of chondropathia and the possibilities of its therapy are described. Patellofemoral arthrography is very helpful for the diagnosis. The technique of our operation is also described. After close study of current available literature and careful control of our 100 medialization cases, the results after 6, 12, 24, and 36 months are shown in tabular form. The operation is recommended for primary chondropathia patellae with lateroposition or lateral-tipped patella.

  9. Post-vaccination frozen shoulder syndrome. Report of 3 cases.

    PubMed

    Degreef, I; Debeer, Ph

    2012-01-01

    The cause of frozen shoulder syndrome is unknown in most cases, although it can be preceded by minor trauma. Here, we report 3 patients with severe frozen shoulder after an intramuscular vaccination in the deltoid muscle. A distention arthrography resulted in good pain relief and improved the mobility. Frozen shoulder syndrome can be a severe manifestation of vaccination-related shoulder dysfunction. Correct intramuscular administration is crucial to prevent post-vaccination frozen shoulder and on the other hand, physicians' awareness is needed to recognize this feature early on.

  10. Imaging Evaluation of Superior Labral Anteroposterior (SLAP) Tears.

    PubMed

    Grubin, Jeremy; Maderazo, Alex; Fitzpatrick, Darren

    2015-10-01

    Superior labral anteroposterior (SLAP) tears are common injuries that are best evaluated with magnetic resonance arthrography (MRA), as it provides the most detailed evaluation of the bicipital labral complex. Given the variety and complexity of SLAP tears, distention of the joint with intra-articular dilute gadolinium contrast properly separates the intra-articular biceps tendon, superior labrum, glenoid cartilage and glenohumeral ligaments to optimize assessment of these structures. This allows for increased diagnostic confidence of the interpreting radiologist and provides a better road map for the surgeon prior to arthroscopy. Indirect MRA and high-field magnetic resonance imaging are sensitive and specific alternative modalities if MRA cannot be performed.

  11. Localized form of pigmented villonodular synovitis of the knee: the meniscal mime.

    PubMed

    Bouguennec, N; Meyer, A; Graveleau, N

    2014-04-01

    The localized form of pigmented villonodular synovitis of the knee is a rare condition with non-specific symptoms. This makes diagnosis especially difficult when the meniscus is affected. A full assessment with several imaging modalities can help support the preoperative diagnosis. But in the case reported here, the full clinical and paraclinical assessment (X-rays, CT arthrography and MRI) was wrong--the localized form of pigmented villonodular synovitis had mimicked a lateral meniscus injury and was only detected during arthroscopy. The lesion was excised surgically and the diagnosis was confirmed through postoperative histopathology.

  12. Algorithm for Imaging the Hip in Adolescents and Young Adults.

    PubMed

    Zoga, Adam C; Hegazi, Tarek M; Roedl, Johannes B

    2016-09-01

    The imager's role in diagnosing prearthritic hip syndromes has increased significantly in the past 10 years. As surgical and nonsurgical treatment algorithms for mechanical syndromes including femoroacetabular impingement and acetabular dysplasia have evolved, clinicians have grown increasingly dependent on radiography, MR imaging, MR arthrography, and even computed tomography to confirm diagnoses and support the need for potential intervention. Musculoskeletal radiologists should help referrers navigate available imaging options and protocols, while using both clinical information and imaging findings to arrive at a diagnosis that adds value to the treatment plan. PMID:27545428

  13. Acetabular labral tears: focused review of anatomy, diagnosis, and current management.

    PubMed

    Huang, Ronald; Diaz, Claudio; Parvizi, Javad

    2012-05-01

    Acetabular labral tears have become an increasingly common diagnosis with the advancement of imaging techniques and hip arthroscopy. Therefore, understanding the anatomic significance, healing potential, and associated pathologies of labral tears is helpful. Furthermore, recognizing the clinical picture and understanding appropriate imaging techniques, such as magnetic resonance arthrography, are essential to making a correct diagnosis. This article reviews the relevant anatomy, diagnosis, and management of acetabular labral tears for physicians of all specialties who may be involved in the care of patients with labral tears. Short-term results of labral repair have been promising, but further studies are needed to clarify appropriate indications and long-term results of treatment. PMID:22759609

  14. Symptomatic hip plica: MR arthrographic and arthroscopic correlation.

    PubMed

    Katz, Lee D; Haims, Andrew; Medvecky, Michael; McCallum, John

    2010-12-01

    Two cases of unilateral hip pain are reported in which MR arthrography demonstrated a prominent band medial to the ligamentum teres, running in the AP direction, consistent with a hip plica. Both patients underwent hip arthroscopy with resection of the band. No labral tear or additional intra-articular pathological features was identified in either case. Both patients became asymptomatic following surgery and have remained such. The pathology report demonstrated the specimens to be a synovial band with fibroconnective tissue. This is the first MR arthrographic report of the identification and resection of a symptomatic hip plica. The symptomatic plica may represent an alternative diagnosis for mechanical hip pain.

  15. Capitate-lunate instability: recognition by manipulation under fluoroscopy.

    PubMed

    White, S J; Louis, D S; Braunstein, E M; Hankin, F M; Greene, T L

    1984-08-01

    Videotape fluoroscopy was used to diagnose a previously undescribed carpal dissociation, the capitate lunate instability pattern. In eight patients with midcarpal pain and clicking, the examiner simultaneously applied pressure to the scaphoid tuberosity while applying longitudinal traction and flexion to the wrist under fluoroscopic control. This maneuver revealed dorsal subluxation of the proximal carpal row and capitate lunate subluxation in each of the eight patients. Plain radiography and arthrography were not helpful in the diagnosis. All eight cases were managed conservatively. Videotape fluoroscopy is the best radiologic method of diagnosing capitate-lunate instability.

  16. [Acute perilunar dislocations: algorithm for treatment].

    PubMed

    Towfigh, H

    2001-01-01

    In most cases, perilunar dislocations of the wrist are caused by high speed accidents. Usually these injuries occur by a fall on the dorsiflexed superextension of the hand. The instability caused by injuries of various erticular structures (ligament, bone) show various developmental stages. Clinical symptoms are reduced and painful movement, instability of the carpus, snapping and swelling. The diagnosis is established by X-ray, cinematography, arthrography MRT or CT. Perilunar instability with or without associated fractures and particularly de Quervain must be reduced and treated operatively including suture of the ligament and stabilization of the fracture. PMID:11824286

  17. An Unusual Left Ventricular Outflow Pseudoaneurysm: Usefulness of Echocardiography and Multidetector Computed Tomography for Surgical Repair

    SciTech Connect

    Da Col, Uberto; Ramoni, Enrico Di Bella, Isidoro; Ragni, Temistocle

    2009-01-15

    Left ventricular outflow tract (LVOT) pseudoaneurysm is a rare but potentially lethal complication, mainly after aortic root endocarditis or surgery. Usually it originates from a dehiscence in the mitral-aortic intervalvular fibrosa and it arises posteriorly to the aortic root. Due to these anatomical features, its imaging assessment is challenging and surgical repair requires complex procedures. An unusual case of LVOT pseudoaneurysm is described. It was detected by transthoracic ecocardiography 7 months after aortic root replacement for acute endocarditis. Multidetector computed tomography (MDCT) confirmed the presence of a pouch located between the aortic root and the right atrium. Computed tomography also detected the origin of the pseudoaneurysm from the muscular interventricular septum of the LVOT, rather below the aortic valve plane. It was repaired with an extracardiac surgical approach, sparing the aortic root bioprosthesis previously implanted. The high-resolution three-dimensional details provided by the preoperative MDCT allowed us to plan a simple and effective surgical strategy.

  18. [Mechanism, imaging technique and therapy for vascular calcification in patients of chronic kidney disease].

    PubMed

    Yoshida, Hiraku; Yokoyama, Keitaro

    2007-05-01

    Vascular calcification has been reported to influence mortality and complications of cardiovascular diseases in patients with chronic kidney disease. Once vascular calcification was thought to the result from passive precipitation of calcium and phosphate, it now appears that end result of phenotypic change of vascular smooth muscle cells (VSMC) into osteoblast-like cells. A variety of imaging technique are available to visualize vascular calcification, including X-ray, vascular ultrasound, electron beam computed tomography (EBCT) and multidetector-row computed tomography (MDCT) . Especially, MDCT with contrast medium that can detect not only coronary calcification but also stenosis is useful and noninvasive methods for screening of coronary artery disease. Through greater understanding of both the mechanism and clinical consequence of vascular calcification, future therapeutic strategies may be more effectively designed and applied. PMID:17471002

  19. Coronary artery anomalies.

    PubMed

    Earls, James P

    2006-12-01

    Coronary artery anomalies are uncommon findings but can be of significant clinical importance in a small number of individuals. Clinical presentation depends on the specific anomaly. Most coronary artery anomalies are benign and clinically insignificant, however, some anomalies are potentially significant and can lead to heart failure and even death. Noninvasive imaging has emerged as the preferred way to image coronary anomalies. Both electron beam computed tomography (EBCT) and magnetic resonance angiography (MRA) are useful for the diagnosis of anomalous coronary arteries. Recently, MDCT has also proven to be very useful in the detection and characterization of anomalous coronary arteries. This chapter will review the appearance of the most commonly encountered coronary anomalies on MDCT. PMID:17709086

  20. Spontaneous appendico-cutaneous fistula: an unusual presentation of retroperitoneal appendicular perforation associated with psoas abscess

    PubMed Central

    Singh, Mahendra Pratap; Samaiya, Atul; Sainia, Tarun Kumar; Saxena, Agamya

    2016-01-01

    Spontaneous appendico-cutaneous fistula is an extremely rare complication of appendicitis and only a few cases are reported in literature. We present one such case in a 65-year-old diabetic male who had recurrent atypical abdominal pain for 32 years. The patient also had recurrent right psoas abscess, which had failed to respond to a repeated surgical drainage, antibiotics and anti-tubercular treatment. Patient presented to us with recurrent discharging sinus in right lumbar region since 6 months. Multi-detector computed tomography (MDCT) suspected the appendicitis as a possible cause. On laparotomy, retroperitoneal perforated appendix tip was found communicating with the fistulous tract. Appendectomy with excision of fistulous tract resulted in cure. To prevent inappropriate treatment and complication in such atypical presentation of appendicitis, high index of suspicion is required and MDCT is a very useful tool for making correct diagnosis. PMID:27340228

  1. The role of multidetector-row CT in the diagnosis, classification and management of acute aortic syndrome

    PubMed Central

    Brown, I W; Peebles, C R; Harden, S P; Shambrook, J S

    2014-01-01

    The term “acute aortic syndrome” (AAS) encompasses several non-traumatic life-threatening pathologies of the thoracic aorta presenting in patients with a similar clinical profile. These include aortic dissection, intramural haematoma and penetrating atherosclerotic ulcers. These different pathological entities can be indistinguishable on clinical grounds alone and may be confused with other causes of chest pain, including myocardial infarction. Multidetector-row CT (MDCT) is the current modality of choice for imaging AAS with a sensitivity and specificity approaching 100%. Early diagnosis and accurate radiological classification is associated with improved clinical outcomes in AAS. We review the characteristic radiological features of the different pathologies that encompass AAS and highlight the vital role of MDCT in determining the management of these life-threatening conditions. PMID:25083552

  2. Multidetector computed tomography of temporomandibular joint: A road less travelled

    PubMed Central

    Pahwa, Shivani; Bhalla, Ashu Seith; Roychaudhary, Ajoy; Bhutia, Ongkila

    2015-01-01

    This article reviews the imaging anatomy of temporomandibular joint (TMJ), describes the technique of multi-detector computed tomography (MDCT) of the TMJ, and describes in detail various osseous pathologic afflictions affecting the joint. Traumatic injuries affecting the mandibular condyle are most common, followed by joint ankylosis as a sequel to arthritis. The congenital anomalies are less frequent, hemifacial microsomia being the most commonly encountered anomaly involving the TMJ. Neoplastic afflictions of TMJ are distinctly uncommon, osteochondroma being one of the most common lesions. MDCT enables comprehensive evaluation of osseous afflictions of TMJ, and is a valuable tool for surgical planning. Sagittal, coronal and 3D reformatted images well depict osseous TMJ lesions, and their relationship to adjacent structures. PMID:25984518

  3. Multidetector-row computed tomography in cerebral hydatid cyst

    PubMed Central

    Wani, Nisar A; Kosar, Tasleem L; Khan, Abdul Qayum; Ahmad, Sheikh Shahnawaz

    2010-01-01

    Intracranial localization is a rare manifestation of hydatid cyst disease (Echinococcosis). It comprises only 2% of cases of Echinococcosis infection even in endemic areas and is predominantly seen in children. Clinical manifestations resulting from raised intracranial tension are nonspecific. Imaging with computed tomography (CT) may suggest the diagnosis preoperatively with reasonable accuracy. Multidetector-row CT (MDCT) with its high resolution multiplanar reformations can demonstrate the relationship of the cyst with adjacent brain structures and thus help in planning surgery. This has a practical utility in places where magnetic resonance imaging is not available. We describe a case of cerebral hydatid cyst in a 13-year-old boy who was diagnosed with MDCT, which helped in planning its surgical removal. PMID:21808517

  4. Trabecular bone class mapping across resolutions: translating methods from HR-pQCT to clinical CT

    NASA Astrophysics Data System (ADS)

    Valentinitsch, Alexander; Fischer, Lukas; Patsch, Janina M.; Bauer, Jan; Kainberger, Franz; Langs, Georg; DiFranco, Matthew

    2015-03-01

    Quantitative assessment of 3D bone microarchitecture in high-resolution peripheral quantitative computed tomography (HR-pQCT) has shown promise in fracture risk assessment and biomechanics, but is limited to the distal radius and tibia. Trabecular microarchitecture classes (TMACs), based on voxel-wise clustering texture and structure tensor features in HRpQCT, is extended in this paper to quantify trabecular bone classes in clinical multi-detector CT (MDCT) images. Our comparison of TMACs in 12 cadaver radii imaged using both HRpQCT and MDCT yields a mean Dice score of up to 0.717+/-0.40 and visually concordant bone quality maps. Further work to develop clinically viable bone quantitative imaging using HR-pQCT validation could have a significant impact on overall bone health assessment.

  5. Lossy Compression of Haptic Data by Using DCT

    NASA Astrophysics Data System (ADS)

    Tanaka, Hiroyuki; Ohnishi, Kouhei

    In this paper, lossy data compression of haptic data is presented and the results of its application to a motion copying system are described. Lossy data compression has been studied and practically applied in audio and image coding. Lossy data compression of the haptic data has been not studied extensively. Haptic data compression using discrete cosine transform (DCT) and modified DCT (MDCT) for haptic data storage are described in this paper. In the lossy compression, calculated DCT/MDCT coefficients are quantized by quantization vector. The quantized coefficients are further compressed by lossless coding based on Huffman coding. The compressed haptic data is applied to the motion copying system, and the results are provided.

  6. Quantification of global left ventricular function: comparison of multidetector computed tomography and magnetic resonance imaging. a meta-analysis and review of the current literature.

    PubMed

    van der Vleuten, P A; Willems, T P; Götte, M J W; Tio, R A; Greuter, M J W; Zijlstra, F; Oudkerk, M

    2006-12-01

    Cardiac morbidity and mortality are closely related to cardiac volumes and global left ventricular (LV) function, expressed as left ventricular ejection fraction. Accurate assessment of these parameters is required for the prediction of prognosis in individual patients as well as in entire cohorts. The current standard of reference for left ventricular function is analysis by short-axis magnetic resonance imaging. In recent years, major extensive technological improvements have been achieved in computed tomography. The most marked development has been the introduction of the multidetector CT (MDCT), which has significantly improved temporal and spatial resolutions. In order to assess the current status of MDCT for analysis of LV function, the current available literature on this subject was reviewed. The data presented in this review indicate that the global left ventricular functional parameters measured by contemporary multi-detector row systems combined with adequate reconstruction algorithms and post-processing tools show a narrow diagnostic window and are interchangeable with those obtained by MRI.

  7. A case of a giant mucocoele of the appendiceal stump presented with a palpable mass in the right thigh: pre-operative diagnosis based on characteristic multidetector CT findings.

    PubMed

    Kim, M K; Lee, H Y; Song, I S; Lee, J B; Kim, G H; Yoo, S M; Rho, J Y; White, C S

    2010-10-01

    The pre-operative diagnosis of a mucocoele of the appendiceal stump (MAS) may be difficult owing to rarity and non-specific clinical presentation. However, a pre-operative diagnosis of a MAS is important to prevent widespread dissemination by inadvertent spillage of mucous contents. We describe a case of a MAS presenting with a palpable mass in the right thigh in which a pre-operative diagnosis was made by characteristic multidetector CT (MDCT) findings.

  8. Determination of the myocardial area at risk with pre- versus post-reperfusion imaging techniques in the pig model.

    PubMed

    Mewton, Nathan; Rapacchi, Stanislas; Augeul, Lionel; Ferrera, René; Loufouat, Joseph; Boussel, Loic; Micolich, Alejandra; Rioufol, Gilles; Revel, Didier; Ovize, Michel; Croisille, Pierre

    2011-11-01

    The purpose of this study was to compare the accuracy of post-reperfusion cardiac magnetic resonance (CMR) and pre-reperfusion multidetector computed tomography (MDCT) imaging to measure the size of the area at risk (AAR), using pathology as a reference technique in a porcine acute myocardial infarction model. Fifteen pigs underwent balloon-induced coronary artery occlusion for 40 min followed by reperfusion. The AAR was assessed with arterial enhanced MDCT performed during occlusion, while two different T2 weighted (T2W) CMR imaging sequences and the contrast-enhanced (ce-) CMR endocardial surface length (ESL) were performed after 90 min of reperfusion. Animals were euthanized and the AAR was assessed by pathology. Additional measurements of the myocardial water content in the AAR, remote and the AAR border zones were performed. AAR by pathology best correlated with measurements made by MDCT (R(2) = 0.88; p < 0.001) with little bias on Bland-Altman plots (bias 2.5%, SD 6.1% LV area). AAR measurements obtained by T2W STIR, T2W ACUTE sequences or the ESL on ce-CMR showed a fair correlation with pathology (R(2) = 0.72, R(2) = 0.65 and R(2) = 0.69, respectively; all p ≤ 0.001), but significantly overestimated the size of the AAR with important bias (17.4 ± 10.8% LV area; 11.7 ± 11.0% LV area; 13.0 ± 10.3% LV area, respectively). The myocardial water content in the AAR border zones was significantly higher than the remote (82.8 vs. 78.8%; p < 0.001). Our data suggest that post-reperfusion imaging methods overestimated the AAR likely due to the presence of edema outside of the boundaries of the AAR. Pre-reperfusion arterial enhanced MDCT showed the greatest accuracy for the assessment of the AAR. PMID:21874556

  9. New absorbed dose measurement with cylindrical water phantoms for multidetector CT

    NASA Astrophysics Data System (ADS)

    Ohno, Takeshi; Araki, Fujio; Onizuka, Ryota; Hioki, Kazunari; Tomiyama, Yuuki; Yamashita, Yusuke

    2015-06-01

    The aim of this study was to develop new dosimetry with cylindrical water phantoms for multidetector computed tomography (MDCT). The ionization measurement was performed with a Farmer ionization chamber at the center and four peripheral points in the body-type and head-type cylindrical water phantoms. The ionization was converted to the absorbed dose using a 60Co absorbed-dose-to-water calibration factor and Monte Carlo (MC) -calculated correction factors. The correction factors were calculated from MDCT (Brilliance iCT, 64-slice, Philips Electronics) modeled with GMctdospp (IMPS, Germany) software based on the EGSnrc MC code. The spectrum of incident x-ray beams and the configuration of a bowtie filter for MDCT were determined so that calculated photon intensity attenuation curves for aluminum (Al) and calculated off-center ratio (OCR) profiles in air coincided with those measured. The MC-calculated doses were calibrated by the absorbed dose measured at the center in both cylindrical water phantoms. Calculated doses were compared with measured doses at four peripheral points and the center in the phantom for various beam pitches and beam collimations. The calibration factors and the uncertainty of the absorbed dose determined using this method were also compared with those obtained by CTDIair (CT dose index in air). Calculated Al half-value layers and OCRs in air were within 0.3% and 3% agreement with the measured values, respectively. Calculated doses at four peripheral points and the centers for various beam pitches and beam collimations were within 5% and 2% agreement with measured values, respectively. The MC-calibration factors by our method were 44-50% lower than values by CTDIair due to the overbeaming effect. However, the calibration factors for CTDIair agreed within 5% with those of our method after correction for the overbeaming effect. Our method makes it possible to directly measure the absorbed dose for MDCT and is more robust and accurate than the

  10. Presentation of floating mass transducer and Vibroplasty couplers on CT and cone beam CT.

    PubMed

    Mlynski, Robert; Nguyen, Thi Dao; Plontke, Stefan K; Kösling, Sabrina

    2014-04-01

    Various titanium coupling elements, Vibroplasty Couplers, maintaining the attachment of the Floating Mass Transducer (FMT) of the active middle ear implant Vibrant Soundbridge (VSB) to the round window, the stapes suprastructure or the stapes footplate are in use to optimally transfer energy from the FMT to the inner ear fluids. In certain cases it is of interest to radiologically verify the correct position of the FMT coupler assembly. The imaging appearance of FMT connected to these couplers, however, is not well known. The aim of this study was to present the radiological appearance of correctly positioned Vibroplasty Couplers together with the FMT using two different imaging techniques. Vibroplasty Couplers were attached to the FMT of a Vibrant Soundbridge and implanted in formalin fixed human temporal bones. Five FMT coupler assemblies were implanted in different positions: conventionally to the incus, a Bell-Coupler, a CliP-Coupler, a Round Window-Coupler and an Oval Window-Coupler. High spatial resolution imaging with Multi-Detector CT (MDCT) and Cone Beam CT (CBCT) was performed in each specimen. Images were blind evaluated by two radiologists on a visual basis. Middle ear details, identification of FMT and coupler, position of FMT coupler assembly and artefacts were assessed. CBCT showed a better spatial resolution and a higher visual image quality than MDCT, but there was no significant advantage over MDCT in delineating the structures or the temporal bone of the FMT Coupler assemblies. The FMT with its coupler element could be clearly identified in the two imaging techniques. The correct positioning of the FMT and all types of couplers could be demonstrated. Both methods, MDCT and CBCT, are appropriate methods for postoperative localization of FMT in combination with Vibroplasty Couplers and for verifying their correct position. If CBCT is available, this method is recommended due to the better spatial resolution and less metal artifacts. PMID:23529745

  11. Method for extracting the aorta from 3D CT images

    NASA Astrophysics Data System (ADS)

    Taeprasartsit, Pinyo; Higgins, William E.

    2007-03-01

    Bronchoscopic biopsy of the central-chest lymph nodes is vital in the staging of lung cancer. Three-dimensional multi-detector CT (MDCT) images provide vivid anatomical detail for planning bronchoscopy. Unfortunately, many lymph nodes are situated close to the aorta, and an inadvertent needle biopsy could puncture the aorta, causing serious harm. As an eventual aid for more complete planning of lymph-node biopsy, it is important to define the aorta. This paper proposes a method for extracting the aorta from a 3D MDCT chest image. The method has two main phases: (1) Off-line Model Construction, which provides a set of training cases for fitting new images, and (2) On-Line Aorta Construction, which is used for new incoming 3D MDCT images. Off-Line Model Construction is done once using several representative human MDCT images and consists of the following steps: construct a likelihood image, select control points of the medial axis of the aortic arch, and recompute the control points to obtain a constant-interval medial-axis model. On-Line Aorta Construction consists of the following operations: construct a likelihood image, perform global fitting of the precomputed models to the current case's likelihood image to find the best fitting model, perform local fitting to adjust the medial axis to local data variations, and employ a region recovery method to arrive at the complete constructed 3D aorta. The region recovery method consists of two steps: model-based and region-growing steps. This region growing method can recover regions outside the model coverage and non-circular tube structures. In our experiments, we used three models and achieved satisfactory results on twelve of thirteen test cases.

  12. Transmural myocardial perfusion gradients in relation to coronary artery stenoses severity assessed by cardiac multidetector computed tomography.

    PubMed

    Linde, Jesper James; Kühl, Jørgen Tobias; Hove, Jens Dahlgaard; Sørgaard, Mathias; Kelbæk, Henning; Nielsen, Walter Bjørn; Kofoed, Klaus Fuglsang

    2015-01-01

    To assess the relationship between epicardial coronary artery stenosis severity and the corresponding regional transmural perfusion at rest and during adenosine stress, using multidetector computed tomography (MDCT). We evaluated the relationship between the severity of coronary artery diameter stenosis assessed by MDCT angiography and semi-quantitative myocardial MDCT perfusion in 200 symptomatic patients. The perfusion index (PI = mean myocardial attenuation density/mean left ventricular lumen attenuation density) at rest and during adenosine stress, the myocardial perfusion reserve (MPR = stress - PI/rest - PI), and the transmural perfusion ratio (TPR = subendocardium/subepicardium) were calculated. A coronary artery stenosis ≥50 % was present in 49 patients (25 %). Rest-PI and rest-TPR values were similar in patients with and without a coronary artery stenosis ≥50 %, whereas stress-PI, stress-TPR and MPR were significantly reduced in patients with a stenosis ≥50 % (p < 0.001, p < 0.0001 and p = 0.02, respectively). Subendocardial PI was significantly higher than subepicardial PI at rest and during stress for patients without a significant stenosis, whereas this difference was blurred during stress in patients with ≥50 % stenosis. In a broad spectrum of stenosis severity groups, TPR at rest remained unchanged until the group of patients with total occlusions, whereas TPR during stress decreased progressively when a threshold of 50 % was superseded. In this study we establish the relationship between semi-quantitative perfusion measurements by MDCT and severity of coronary artery stenoses and find the transmural myocardial perfusion ratio to be a potential strong functional index of the hemodynamic significance of coronary artery atherosclerotic lesions.

  13. New absorbed dose measurement with cylindrical water phantoms for multidetector CT.

    PubMed

    Ohno, Takeshi; Araki, Fujio; Onizuka, Ryota; Hioki, Kazunari; Tomiyama, Yuuki; Yamashita, Yusuke

    2015-06-01

    The aim of this study was to develop new dosimetry with cylindrical water phantoms for multidetector computed tomography (MDCT). The ionization measurement was performed with a Farmer ionization chamber at the center and four peripheral points in the body-type and head-type cylindrical water phantoms. The ionization was converted to the absorbed dose using a (60)Co absorbed-dose-to-water calibration factor and Monte Carlo (MC) -calculated correction factors. The correction factors were calculated from MDCT (Brilliance iCT, 64-slice, Philips Electronics) modeled with GMctdospp (IMPS, Germany) software based on the EGSnrc MC code. The spectrum of incident x-ray beams and the configuration of a bowtie filter for MDCT were determined so that calculated photon intensity attenuation curves for aluminum (Al) and calculated off-center ratio (OCR) profiles in air coincided with those measured. The MC-calculated doses were calibrated by the absorbed dose measured at the center in both cylindrical water phantoms. Calculated doses were compared with measured doses at four peripheral points and the center in the phantom for various beam pitches and beam collimations. The calibration factors and the uncertainty of the absorbed dose determined using this method were also compared with those obtained by CTDIair (CT dose index in air). Calculated Al half-value layers and OCRs in air were within 0.3% and 3% agreement with the measured values, respectively. Calculated doses at four peripheral points and the centers for various beam pitches and beam collimations were within 5% and 2% agreement with measured values, respectively. The MC-calibration factors by our method were 44-50% lower than values by CTDIair due to the overbeaming effect. However, the calibration factors for CTDIair agreed within 5% with those of our method after correction for the overbeaming effect. Our method makes it possible to directly measure the absorbed dose for MDCT and is more robust and accurate than the

  14. Detection of Cement Leakage After Vertebroplasty with a Non-Flat-Panel Angio Unit Compared to Multidetector Computed Tomography - An Ex Vivo Study

    SciTech Connect

    Baumann, Clemens Fuchs, Heiko; Westphalen, Kerstin; Hierholzer, Johannes

    2008-11-15

    The purpose of this study was to investigate the detection of cement leakages after vertebroplasty using angiographic computed tomography (ACT) in a non-flat-panel angio unit compared to multidetector computed tomography (MDCT). Vertebroplasty was performed in 19 of 33 cadaver vertebrae (23 thoracic and 10 lumbar segments). In the angio suite, ACT (190{sup o}; 1.5{sup o} per image) was performed to obtain volumetric data. Another volumetric data set of the specimen was obtained by MDCT using a standard algorithm. Nine multiplanar reconstructions in standardized axial, coronal, and sagittal planes of every vertebra were generated from both data sets. Images were evaluated on the basis of a nominal scale with 18 criteria, comprising osseous properties (e.g., integrity of the end plate) and cement distribution (e.g., presence of intraspinal cement). MDCT images were regarded as gold standard and analyzed by two readers in a consensus mode. Rotational acquisitions were analyzed by six blinded readers. Results were correlated with the gold standard using Cohen's {kappa}-coefficient analysis. Furthermore, interobserver variability was calculated. Correlation with the gold standard ranged from no correlation (osseous margins of the neuroforamen, {kappa} = 0.008) to intermediate (trace of vertebroplasty canula; {kappa} = 0.615) for criteria referring to osseous morphology. However, there was an excellent correlation for those criteria referring to cement distribution, with {kappa} values ranging from 0.948 (paravertebral cement distribution) to 0.972 (intraspinal cement distribution). With a minimum of {kappa} = 0.768 ('good correlation') and a maximum of {kappa} = 0.91 ('excellent'), interobserver variability was low. In conclusion, ACT in an angio suite without a flat-panel detector depicts a cement leakage after vertebroplasty as well as MDCT. However, the method does not provide sufficient depiction of osseous morphology.

  15. A method of estimating conceptus doses resulting from multidetector CT examinations during all stages of gestation

    SciTech Connect

    Damilakis, John; Tzedakis, Antonis; Perisinakis, Kostas; Papadakis, Antonios E.

    2010-12-15

    Purpose: Current methods for the estimation of conceptus dose from multidetector CT (MDCT) examinations performed on the mother provide dose data for typical protocols with a fixed scan length. However, modified low-dose imaging protocols are frequently used during pregnancy. The purpose of the current study was to develop a method for the estimation of conceptus dose from any MDCT examination of the trunk performed during all stages of gestation. Methods: The Monte Carlo N-Particle (MCNP) radiation transport code was employed in this study to model the Siemens Sensation 16 and Sensation 64 MDCT scanners. Four mathematical phantoms were used, simulating women at 0, 3, 6, and 9 months of gestation. The contribution to the conceptus dose from single simulated scans was obtained at various positions across the phantoms. To investigate the effect of maternal body size and conceptus depth on conceptus dose, phantoms of different sizes were produced by adding layers of adipose tissue around the trunk of the mathematical phantoms. To verify MCNP results, conceptus dose measurements were carried out by means of three physical anthropomorphic phantoms, simulating pregnancy at 0, 3, and 6 months of gestation and thermoluminescence dosimetry (TLD) crystals. Results: The results consist of Monte Carlo-generated normalized conceptus dose coefficients for single scans across the four mathematical phantoms. These coefficients were defined as the conceptus dose contribution from a single scan divided by the CTDI free-in-air measured with identical scanning parameters. Data have been produced to take into account the effect of maternal body size and conceptus position variations on conceptus dose. Conceptus doses measured with TLD crystals showed a difference of up to 19% compared to those estimated by mathematical simulations. Conclusions: Estimation of conceptus doses from MDCT examinations of the trunk performed on pregnant patients during all stages of gestation can be made

  16. Extensive propagation of a pancreatic pseudocyst along the lower limb through the sciatic foramen.

    PubMed

    Coulier, B; Maldague, P; Bueres-Dominguez, I; Ramboux, A; Pierard, F; Bienfait, B

    2012-01-01

    The extremely rare extensive propagation of a giant retroperitoneal pancreatic pseudocyst into the posterior compartment of the lower limb as far as the knee is reported. The extension was found producing through the sciatic foramen and the full diagnosis was made by MDCT. A complete healing was progressively obtained in the 78-year old female after a six months period of sequential multidisciplinary therapeutic approach comprising combined medical and surgical intra-abdominal and external drainage.

  17. Construction of a multimodal CT-video chest model

    NASA Astrophysics Data System (ADS)

    Byrnes, Patrick D.; Higgins, William E.

    2014-03-01

    Bronchoscopy enables a number of minimally invasive chest procedures for diseases such as lung cancer and asthma. For example, using the bronchoscope's continuous video stream as a guide, a physician can navigate through the lung airways to examine general airway health, collect tissue samples, or administer a disease treatment. In addition, physicians can now use new image-guided intervention (IGI) systems, which draw upon both three-dimensional (3D) multi-detector computed tomography (MDCT) chest scans and bronchoscopic video, to assist with bronchoscope navigation. Unfortunately, little use is made of the acquired video stream, a potentially invaluable source of information. In addition, little effort has been made to link the bronchoscopic video stream to the detailed anatomical information given by a patient's 3D MDCT chest scan. We propose a method for constructing a multimodal CT-video model of the chest. After automatically computing a patient's 3D MDCT-based airway-tree model, the method next parses the available video data to generate a positional linkage between a sparse set of key video frames and airway path locations. Next, a fusion/mapping of the video's color mucosal information and MDCT-based endoluminal surfaces is performed. This results in the final multimodal CT-video chest model. The data structure constituting the model provides a history of those airway locations visited during bronchoscopy. It also provides for quick visual access to relevant sections of the airway wall by condensing large portions of endoscopic video into representative frames containing important structural and textural information. When examined with a set of interactive visualization tools, the resulting fused data structure provides a rich multimodal data source. We demonstrate the potential of the multimodal model with both phantom and human data.

  18. Diagnosis and Treatment of Hemoptysis.

    PubMed

    Cordovilla, Rosa; Bollo de Miguel, Elena; Nuñez Ares, Ana; Cosano Povedano, Francisco Javier; Herráez Ortega, Inmaculada; Jiménez Merchán, Rafael

    2016-07-01

    Hemoptysis is the expectoration of blood from the tracheobronchial tree. It is commonly caused by bronchiectasis, chronic bronchitis, and lung cancer. The expectorated blood usually originates from the bronchial arteries. When hemoptysis is suspected, it must be confirmed and classified according to severity, and the origin and cause of the bleeding determined. Lateral and AP chest X-ray is the first study, although a normal chest X-ray does not rule out the possibility of malignancy or other underlying pathology. Multidetector computed tomography (MDCT) must be performed in all patients with frank hemoptysis, hemoptoic sputum, suspicion of bronchiectasis or risk factors for lung cancer, and in those with signs of pathology on chest X-ray. MDCT angiography has replaced arteriography in identifying the arteries that are the source of bleeding. MDCT angiography is a non-invasive imaging technique that can pinpoint the presence, origin, number and course of the systemic thoracic (bronchial and non-bronchial) and pulmonary arterial sources of bleeding. Endovascular embolization is the safest and most effective method of managing bleeding in massive or recurrent hemoptysis. Embolization is indicated in all patients with life-threatening or recurrent hemoptysis in whom MDCT angiography shows artery disease. Flexible bronchoscopy plays a pivotal role in the diagnosis of hemoptysis in patients with hemoptoic sputum or frank hemoptysis. The procedure can be performed rapidly at the bedside (intensive care unit); it can be used for immediate control of bleeding, and is also effective in locating the source of the hemorrhage. Flexible bronchoscopy is the first-line procedure of choice in hemodynamically unstable patients with life-threatening hemoptysis, in whom control of bleeding is of vital importance. In these cases, surgery is associated with an extremely high mortality rate, and is currently only indicated when bleeding is secondary to surgery and its source can be

  19. Interventional articular and para-articular knee procedures.

    PubMed

    Lalam, Radhesh K; Winn, Naomi; Cassar-Pullicino, Victor N

    2016-01-01

    The knee is a common area of the body to undergo interventional procedures. This article discusses image-guided interventional issues specific to the knee area. The soft tissues in and around the knee are frequently affected by sport-related injuries and often need image-guided intervention. This article details the specific technical issues related to intervention in these soft tissues, including the iliotibial tract, fat pads, patellar tendon and other tendons, bursae and the meniscus. Most often, simple procedures such as injection and aspiration are performed without image guidance. Rarely image-guided diagnostic arthrography and therapeutic joint injections are necessary. The technique, indications and diagnostic considerations for arthrography are discussed in this article. Primary bone and soft-tissue tumours may involve the knee and adjacent soft tissues. Image-guided biopsies are frequently necessary for these lesions; this article details the technical issues related to image-guided biopsy around the knee. A number of newer ablation treatments are now available, including cryoablation, high-frequency ultrasound and microwave ablation. Radiofrequency ablation, however, still remains the most commonly employed ablation technique. The indications, technical and therapeutic considerations related to the application of this technique around the knee are discussed here. Finally, we briefly discuss some newer, but as of yet, unproven image-guided interventions for osteochondral lesions and Brodie's abscess. PMID:26682669

  20. Advanced imaging of the scapholunate ligamentous complex.

    PubMed

    Shahabpour, Maryam; Staelens, Barbara; Van Overstraeten, Luc; De Maeseneer, Michel; Boulet, Cedric; De Mey, Johan; Scheerlinck, Thierry

    2015-12-01

    The scapholunate joint is one of the most involved in wrist injuries. Its stability depends on primary and secondary stabilisers forming together the scapholunate complex. This ligamentous complex is often evaluated by wrist arthroscopy. To avoid surgery as diagnostic procedure, optimization of MR imaging parameters as use of three-dimensional (3D) sequences with very thin slices and high spatial resolution, is needed to detect lesions of the intrinsic and extrinsic ligaments of the scapholunate complex. The paper reviews the literature on imaging of radial-sided carpal ligaments with advanced computed tomographic arthrography (CTA) and magnetic resonance arthrography (MRA) to evaluate the scapholunate complex. Anatomy and pathology of the ligamentous complex are described and illustrated with CTA, MRA and corresponding arthroscopy. Sprains, mid-substance tears, avulsions and fibrous infiltrations of carpal ligaments could be identified on CTA and MRA images using 3D fat-saturated PD and 3D DESS (dual echo with steady-state precession) sequences with 0.5-mm-thick slices. Imaging signs of scapholunate complex pathology include: discontinuity, nonvisualization, changes in signal intensity, contrast extravasation (MRA), contour irregularity and waviness and periligamentous infiltration by edema, granulation tissue or fibrosis. Based on this preliminary experience, we believe that 3 T MRA using 3D sequences with 0.5-mm-thick slices and multiplanar reconstructions is capable to evaluate the scapholunate complex and could help to reduce the number of diagnostic arthroscopies.

  1. A new pain provocation test for superior labral tears of the shoulder.

    PubMed

    Mimori, K; Muneta, T; Nakagawa, T; Shinomiya, K

    1999-01-01

    We prospectively evaluated the usefulness of a new pain provocation test to diagnose superior labral tears in 32 patients with diagnosed throwing injuries of the shoulder. Results of the pain provocation test were compared with findings on magnetic resonance arthrography (all 32 patients) and arthroscopic examination (15 patients). In 22 patients, detachment of the superior labrum was observed on arthrograms, and all of them had positive results on the new pain provocation test. Nine of the other 10 patients had negative results on the new pain provocation test. However, 1 of the 10 patients had a positive result. Eleven of 15 patients were found to have superior labral lesions arthroscopically, and all of them were classified as type II superior labral anterior posterior lesions. All the 11 patients had positive pain provocation tests. The other four patients without superior labral tears on arthroscopic findings had negative results on the new pain provocation test. The new pain provocation test identified all patients with detachment of the superior labrum confirmed by magnetic resonance arthrography, for a sensitivity of 100%, a specificity of 90%, and an accuracy of 97%. Results of the new pain provocation test were in accord with arthroscopic findings in the 15 patients who underwent arthroscopic examination.

  2. Identification of Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species by repetitive-sequence-based PCR.

    PubMed

    Pounder, June I; Hansen, Dewey; Woods, Gail L

    2006-08-01

    The performance of repetitive-sequence-based PCR (rep-PCR) using the DiversiLab system for identification of Coccidioides species, Blastomyces dermatitidis, and Histoplasma capsulatum was assessed by comparing data obtained to colony morphology and microscopic characteristics and to nucleic acid probe results. DNA from cultures of 23 Coccidioides, 24 B. dermatitidis, 24 H. capsulatum, 3 Arthrographis, and 2 Malbranchea isolates was extracted using a microbial DNA isolation kit as recommended by Bacterial Barcodes, Inc. Rep-PCR and probe results agreed for 97.2% of the dimorphic fungi when > or =85% similarity was used as the criterion for identification. Two H. capsulatum isolates were not identified, but no isolates were misidentified. From 43 of those cultures (15 Coccidioides, 14 B. dermatitidis, 14 H. capsulatum, 3 Arthrographis, and 2 Malbranchea), DNA also was extracted using an IDI lysis kit, a simpler method. Rep-PCR and probe results agreed for 97.7% of the dimorphic fungi when a criterion of > or =90% similarity was used for identification. One H. capsulatum isolate could not be identified; no isolates were misidentified. Using > or =85% similarity for identification resulted in one misidentification. These data suggest that the DiversiLab system can be used to identify Coccidioides and B. dermatitidis and, possibly, H. capsulatum isolates. PMID:16891521

  3. Interventional articular and para-articular knee procedures.

    PubMed

    Lalam, Radhesh K; Winn, Naomi; Cassar-Pullicino, Victor N

    2016-01-01

    The knee is a common area of the body to undergo interventional procedures. This article discusses image-guided interventional issues specific to the knee area. The soft tissues in and around the knee are frequently affected by sport-related injuries and often need image-guided intervention. This article details the specific technical issues related to intervention in these soft tissues, including the iliotibial tract, fat pads, patellar tendon and other tendons, bursae and the meniscus. Most often, simple procedures such as injection and aspiration are performed without image guidance. Rarely image-guided diagnostic arthrography and therapeutic joint injections are necessary. The technique, indications and diagnostic considerations for arthrography are discussed in this article. Primary bone and soft-tissue tumours may involve the knee and adjacent soft tissues. Image-guided biopsies are frequently necessary for these lesions; this article details the technical issues related to image-guided biopsy around the knee. A number of newer ablation treatments are now available, including cryoablation, high-frequency ultrasound and microwave ablation. Radiofrequency ablation, however, still remains the most commonly employed ablation technique. The indications, technical and therapeutic considerations related to the application of this technique around the knee are discussed here. Finally, we briefly discuss some newer, but as of yet, unproven image-guided interventions for osteochondral lesions and Brodie's abscess.

  4. Comparison between clinical indicators of transmembrane oxygenator thrombosis and multidetector computed tomographic analysis.

    PubMed

    Panigada, Mauro; L'Acqua, Camilla; Passamonti, Serena Maria; Mietto, Cristina; Protti, Alessandro; Riva, Roberto; Gattinoni, Luciano

    2015-04-01

    This study aims to assess whether multidetector computed tomography (MDCT) could accurately confirm the clinical suspicion of transmembrane oxygenator thrombosis (MOT) during extracorporeal membrane oxygenation (ECMO). Twenty-seven oxygenators were examined using MDCT at the end of patient treatment. Transmembrane oxygenator thrombosis was suspected in 15 of them according to the presence of at least 2 of the following clinical indicators: (1) increase in d-dimer, (2) decrease in platelet count, (3) decrease in oxygenator performance, and (4) presence of clots on the surface of the oxygenator. Transmembrane oxygenator thrombosis was confirmed by MDCT in 5 (33%) of them. Transmembrane oxygenator thrombosis was unexpectedly found in 5 (41%) of the remaining 12 oxygenators not suspected for MOT. Eight (80%) of these oxygenators had clots accounting for less than 1% of total volume. Clots were mainly detectable at the apical corner of the oxygenator, most likely due to greater blood stasis. We found a significant increase in d-dimer and in membrane oxygenator shunt and a decrease in platelet count from the start to the discontinuation of ECMO. Hemostatic abnormalities significantly reverted 48 hours after oxygenator removal, suggesting the role of ECMO in activation of the coagulation cascade. Multidetector computed tomographic scan could not accurately confirm the clinical suspicion of MOT.

  5. Robust system for human airway-tree segmentation

    NASA Astrophysics Data System (ADS)

    Graham, Michael W.; Gibbs, Jason D.; Higgins, William E.

    2008-03-01

    Robust and accurate segmentation of the human airway tree from multi-detector computed-tomography (MDCT) chest scans is vital for many pulmonary-imaging applications. As modern MDCT scanners can detect hundreds of airway tree branches, manual segmentation and semi-automatic segmentation requiring significant user intervention are impractical for producing a full global segmentation. Fully-automated methods, however, may fail to extract small peripheral airways. We propose an automatic algorithm that searches the entire lung volume for airway branches and poses segmentation as a global graph-theoretic optimization problem. The algorithm has shown strong performance on 23 human MDCT chest scans acquired by a variety of scanners and reconstruction kernels. Visual comparisons with adaptive region-growing results and quantitative comparisons with manually-defined trees indicate a high sensitivity to peripheral airways and a low false-positive rate. In addition, we propose a suite of interactive segmentation tools for cleaning and extending critical areas of the automatically segmented result. These interactive tools have potential application for image-based guidance of bronchoscopy to the periphery, where small, terminal branches can be important visual landmarks. Together, the automatic segmentation algorithm and interactive tool suite comprise a robust system for human airway-tree segmentation.

  6. Predicting the biomechanical strength of proximal femur specimens with Minkowski functionals and support vector regression

    NASA Astrophysics Data System (ADS)

    Yang, Chien-Chun; Nagarajan, Mahesh B.; Huber, Markus B.; Carballido-Gamio, Julio; Bauer, Jan S.; Baum, Thomas; Eckstein, Felix; Lochmüller, Eva-Maria; Link, Thomas M.; Wismüller, Axel

    2014-03-01

    Regional trabecular bone quality estimation for purposes of femoral bone strength prediction is important for improving the clinical assessment of osteoporotic fracture risk. In this study, we explore the ability of 3D Minkowski Functionals derived from multi-detector computed tomography (MDCT) images of proximal femur specimens in predicting their corresponding biomechanical strength. MDCT scans were acquired for 50 proximal femur specimens harvested from human cadavers. An automated volume of interest (VOI)-fitting algorithm was used to define a consistent volume in the femoral head of each specimen. In these VOIs, the trabecular bone micro-architecture was characterized by statistical moments of its BMD distribution and by topological features derived from Minkowski Functionals. A linear multiregression analysis and a support vector regression (SVR) algorithm with a linear kernel were used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction result was obtained from the Minkowski Functional surface used in combination with SVR, which had the lowest prediction error (RMSE = 0.939 ± 0.345) and which was significantly lower than mean BMD (RMSE = 1.075 ± 0.279, p<0.005). Our results indicate that the biomechanical strength prediction can be significantly improved in proximal femur specimens with Minkowski Functionals extracted from on MDCT images used in conjunction with support vector regression.

  7. A Scheduling Algorithm for Connected Target Coverage in Rotatable Directional Sensor Networks

    NASA Astrophysics Data System (ADS)

    Han, Youn-Hee; Kim, Chan-Myung; Gil, Joon-Min

    A key challenge in developing energy-efficient sensor networks is to extend network lifetime in resource-limited environments. As sensors are often densely distributed, they can be scheduled on alternative duty cycles to conserve energy while satisfying the system requirements. Directional sensor networks composed of a large number of directional sensors equipped with a limited battery and with a limited angle of sensing have recently attracted attention. Many types of directional sensors can rotate to face a given direction. Maximizing network lifetime while covering all of the targets in a given area and forwarding sensor data to the sink is a challenge in developing such rotatable directional sensor networks. In this paper, we address the maximum directional cover tree (MDCT) problem of organizing directional sensors into a group of non-disjoint subsets to extend network lifetime. One subset, in which the directional sensors cover all of the targets and forward the data to the sink, is activated at a time, while the others sleep to conserve energy. For the MDCT problem, we first present an energy-consumption model that mainly takes into account the energy expenditure for sensor rotation as well as for the sensing and relaying of data. We also develop a heuristic scheduling algorithm called directional coverage and connectivity (DCC)-greedy to solve the MDCT problem. To verify and evaluate the algorithm, we conduct extensive simulations and show that it extends network lifetime to a reasonable degree.

  8. Benefits of contrast-enhanced multidetector row CT colonography for preoperative staging in colorectal cancer patients

    NASA Astrophysics Data System (ADS)

    Iinuma, Gen; Moriyama, Noriyuki; Satake, Mitso; Miyakawa, Kunihisa; Muramatsu, Yukio; Tateishi, Ukihide; Akasu, Takayuki; Otake, Yousuke; Fujii, Takahiro; Kobayashi, Toshiaki

    2003-05-01

    Recently, CT colonography has been recognized as an effective option for evaluating colorectal polyps in the USA. We have applied this technique to preoperative staging of colorectal cancer patients with a contrast-enhanced multi-detector row CT (MDCT). The use of manipulated multi-planar reconstruction (MPR) views in contrast-enhanced MDCT colonography proved advantageous for detecting lymph node metastases. Furthermore, 3-dimensional (3D) endoluminal images with Hansfield-transparency settings allowed vascular views of the colorectal wall for identification of invasive colorectal cancers. Using endoluminal images, increase in flow and pooling of blood related to angiogenesis of invasive cancer could be demonstrated, not only in the lymph nodes but also in the colorectal wall. Both MPR views and 3D endoluminal images can be acquired from the same 3D volumetric data generated by helical scanning in MDCT colonography, and both have great potential as modalities for computer-aided diagnosis (CAD) using blood flow information. Therefore the use of CAD can be expected to improve radiologists' diagnostic performance with regard to colorectal cancer.

  9. Role of cardiac CTA in estimating left ventricular volumes and ejection fraction

    PubMed Central

    Singh, Robin Man; Singh, Balkrishna Man; Mehta, Jawahar Lal

    2014-01-01

    Left ventricular ejection fraction (LVEF) is an important predictor of cardiac outcome and helps in making important diagnostic and therapeutic decisions such as the treatment of different types of congestive heart failure or implantation of devices like cardiac resynchronization therapy-defibrillator. LVEF can be measured by various techniques such as transthoracic echocardiography, contrast ventriculography, radionuclide techniques, cardiac magnetic resonance imaging and cardiac computed tomographic angiography (CTA). The development of cardiac CTA using multi-detector row CT (MDCT) has seen a very rapid improvement in the technology for identifying coronary artery stenosis and coronary artery disease in the last decade. During the acquisition, processing and analysis of data to study coronary anatomy, MDCT provides a unique opportunity to measure left ventricular volumes and LVEF simultaneously with the same data set without the need for additional contrast or radiation exposure. The development of semi-automated and automated software to measure LVEF has now added uniformity, efficiency and reproducibility of practical value in clinical practice rather than just being a research tool. This article will address the feasibility, the accuracy and the limitations of MDCT in measuring LVEF. PMID:25276310

  10. Perforating branches of the internal thoracic artery in women with breast cancer: an anatomical study for breast-conservation surgery.

    PubMed

    Nakatani, Kimiko; Maeda, Hironori; Tanaka, Yousuke; Hamada, Norihiko; Nishioka, Akihito; Sasaguri, Shiro; Ogawa, Yasuhiro

    2008-05-01

    Breast reconstruction after breast-conservation surgery is an important issue for breast cancer patients. Various factors are associated with complications, of which blood flow is one of the more important. The perforating branches of the internal thoracic artery (ITA) are key contributors to blood flow in the anterior chest wall. The present study examined the distributions and depths of the perforating branches of the internal thoracic artery using a multi-detector row-computed tomography (MDCT) angiography. The subjects in this prospective study comprised of 38 women with suspected breast cancer who underwent MDCT angiography. The images were analyzed on computer using transverse MDCT source data and volume renderings. A total of 47 perforating branches were found, with 27 (57.4%) originating in the second, 6 (12.8%) in the third and fourth, 5 (10.6%) in the first and 2 branches (4.3%) originating in the fifth intercostal space, with one branch (2.1%) originating opposite the first intercostal space. A strong correlation was identified between the distance from the skin to the branch and adipose thickness at the shallowest and deepest points (P<0.001). The distributions and depths of the perforating branches of ITA identified in this study may be helpful in immediate breast reconstruction following mastectomy or breast-conserving surgery.

  11. Acute Perforated Diverticulitis: Assessment With Multidetector Computed Tomography.

    PubMed

    Sessa, Barbara; Galluzzo, Michele; Ianniello, Stefania; Pinto, Antonio; Trinci, Margherita; Miele, Vittorio

    2016-02-01

    Colonic diverticulitis is a common condition in the western population. Complicated diverticulitis is defined as the presence of extraluminal air or abscess, peritonitis, colon occlusion, or fistulas. Multidetector row computed tomography (MDCT) is the modality of choice for the diagnosis and the staging of diverticulitis and its complications, which enables performing an accurate differential diagnosis and addressing the patients to a correct management. MDCT is accurate in diagnosing the site of perforation in approximately 85% of cases, by the detection of direct signs (focal bowel wall discontinuity, extraluminal gas, and extraluminal enteric contrast) and indirect signs, which are represented by segmental bowel wall thickening, abnormal bowel wall enhancement, perivisceral fat stranding of fluid, and abscess. MDCT is accurate in the differentiation from complicated colon diverticulitis and colon cancer, often with a similar imaging. The computed tomography-guided classification is recommended to discriminate patients with mild diverticulitis, generally treated with antibiotics, from those with severe diverticulitis with a large abscess, which may be drained with a percutaneous approach.

  12. COMPUTED TOMOGRAPHIC AND ULTRASONOGRAPHIC CHARACTERISTICS OF CAVERNOUS TRANSFORMATION OF THE OBSTRUCTED PORTAL VEIN IN SMALL ANIMALS.

    PubMed

    Specchi, Swan; Pey, Pascaline; Ledda, Gianluca; Lustgarten, Meghann; Thrall, Donald; Bertolini, Giovanna

    2015-01-01

    In humans, the process of development of collateral vessels with hepatopetal flow around the portal vein in order to bypass an obstruction is called "cavernous transformation of the portal vein." The purpose of this retrospective, cross-sectional, multicentric study was to describe presumed cavernous transformation of the portal vein in small animals with portal vein obstruction using ultrasound and multidetector-row computed tomography (MDCT). Databases from three different institutions were searched for patients with an imaging diagnosis of cavernous transformation of the portal vein secondary to portal vein obstruction of any cause. Images were retrieved and reanalyzed. With MDCT-angiography, two main portoportal collateral pathways were identified: short tortuous portoportal veins around/inside the thrombus and long portoportal collaterals bypassing the site of portal obstruction. Three subtypes of the long collaterals, often coexisting, were identified. Branches of the hepatic artery where involved in collateral circulation in nine cases. Concomitant acquired portosystemic shunts were identified in six patients. With ultrasound, cavernous transformation of the portal vein was suspected in three dogs and one cat based on visualization of multiple and tortuous vascular structures corresponding to periportal collaterals. In conclusion, the current study provided descriptive MDCT and ultrasonographic characteristics of presumed cavernous transformation of the portal vein in a sample of small animals. Cavernous transformation of the portal vein could occur as a single condition or could be concurrent with acquired portosystemic shunts.

  13. CT pulmonary densitovolumetry in patients with acromegaly: a comparison between active disease and controlled disease

    PubMed Central

    Camilo, Gustavo B; Carvalho, Alysson R S; Machado, Dequitier C; Mogami, Roberto; Melo, Pedro L

    2015-01-01

    Objective: Our purpose was to compare the findings of CT pulmonary densitovolumetry and pulmonary function in patients with active acromegaly and controlled acromegaly and, secondarily, to correlate these findings. Methods: 11 patients with active acromegaly, 18 patients with controlled acromegaly and 17 control subjects, all non-smokers, underwent quantification of lung volume using multidetector CT (Q-MDCT) and pulmonary function tests. Results: Patients with active acromegaly had larger total lung mass (TLM) values than the controls and larger amounts of non-aerated compartments than the other two groups. Patients with active acromegaly also had larger amounts of poorly aerated compartments than the other two groups, a difference that was observed in both total lung volume (TLV) and TLM. TLV as measured by inspiratory Q-MDCT correlated significantly with total lung capacity, whereas TLV measured using expiratory Q-MDCT correlated significantly with functional residual capacity. Conclusion: Patients with active acromegaly have more lung mass and larger amounts of non-aerated and poorly aerated compartments. There is a relationship between the findings of CT pulmonary densitovolumetry and pulmonary function test parameters. Advances in knowledge: Although the nature of our results demands further investigation, our data suggest that both CT pulmonary densitovolumetry and pulmonary function tests can be used as useful tools for patients with acromegaly by assisting in the prediction of disease activity. PMID:26246281

  14. Stature estimation based on measurements of the sternal medullary cavity using multidetector computed tomography images of Japanese cadavers.

    PubMed

    Torimitsu, Suguru; Makino, Yohsuke; Saitoh, Hisako; Sakuma, Ayaka; Ishii, Namiko; Hayakawa, Mutsumi; Yajima, Daisuke; Inokuchi, Go; Motomura, Ayumi; Chiba, Fumiko; Iwase, Hirotaro

    2014-09-01

    Stature estimation using a skeleton is important for the medicolegal investigation of unidentified human remains. The aims of this study were to identify a correlation between stature and measurements of the sternal medullary cavity using multidetector computed tomography (MDCT) and derive regression equations for stature estimation in the Japanese population. Measurements were conducted on 215 Japanese subjects (107 males, 108 females) who underwent postmortem computed tomography with subsequent forensic autopsy between May 2012 and January 2014. For assessment, MDCT cross-sections through the mid-point of the first costal facets were chosen. The length of a rising diagonal stroke from the bottom left to the top right of the sternal medullary cavity (RS) and the length of a falling diagonal stroke from top left to bottom right of the sternal medullary cavity (FS) were measured. Statistical analyses indicated that both RS and FS were positively correlated with stature regardless of sex. The correlations were stronger for males than for females. The correlation coefficients for RS were higher than those for FS, and standard errors of estimation calculated by regression analysis using RS were lower than those using FS regardless of sex. Measurement of the sternal medullary cavity using MDCT images may be a potentially useful tool for stature estimation, particularly in cases where better predictors such as long bones are not available. PMID:25082372

  15. Myeloid dendritic cells induce HIV-1 latency in non-proliferating CD4+ T cells.

    PubMed

    Evans, Vanessa A; Kumar, Nitasha; Filali, Ali; Procopio, Francesco A; Yegorov, Oleg; Goulet, Jean-Philippe; Saleh, Suha; Haddad, Elias K; da Fonseca Pereira, Candida; Ellenberg, Paula C; Sekaly, Rafick-Pierre; Cameron, Paul U; Lewin, Sharon R

    2013-01-01

    Latently infected resting CD4(+) T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed is critical to identifying novel strategies to eliminate latently infected cells. We demonstrate here that co-culture of resting CD4(+) T cells and syngeneic myeloid dendritic cells (mDC) can dramatically increase the frequency of HIV DNA integration and latent HIV infection in non-proliferating memory, but not naïve, CD4(+) T cells. Latency was eliminated when cell-to-cell contact was prevented in the mDC-T cell co-cultures and reduced when clustering was minimised in the mDC-T cell co-cultures. Supernatants from infected mDC-T cell co-cultures did not facilitate the establishment of latency, consistent with cell-cell contact and not a soluble factor being critical for mediating latent infection of resting CD4(+) T cells. Gene expression in non-proliferating CD4(+) T cells, enriched for latent infection, showed significant changes in the expression of genes involved in cellular activation and interferon regulated pathways, including the down-regulation of genes controlling both NF-κB and cell cycle. We conclude that mDC play a key role in the establishment of HIV latency in resting memory CD4(+) T cells, which is predominantly mediated through signalling during DC-T cell contact.

  16. Dressing up Nanoparticles: A Membrane Wrap to Induce Formation of the Virological Synapse.

    PubMed

    Yu, Xinwei; Xu, Fangda; Ramirez, Nora-Guadalupe P; Kijewski, Suzanne D G; Akiyama, Hisashi; Gummuluru, Suryaram; Reinhard, Björn M

    2015-01-01

    Next-generation nanoparticle-based drug delivery systems require the ability to target specific organelles or subcellular regions in selected target cells. Human immunodeficiency virus type I (HIV-1) particles are evolutionarily optimized nanocarriers that have evolved to avoid intracellular degradation and achieve enrichment at the synapse between mature dendritic cells (mDCs) and T cells by subverting cellular trafficking mechanisms. This study demonstrates that integration of the glycosphingolipid, GM3, in a membrane around a solid nanoparticle (NP) core is sufficient to recapitulate key aspects of the virus particle trafficking in mDCs. GM3-presenting artificial virus NPs (GM3-AVNs) accumulate in CD169(+) and CD81(+) nonlysosomal compartments in an actin-dependent process that mimics the sequestration of HIV-1. Live-cell optical tracking studies reveal a preferential recruitment and arrest of surface scanning CD4(+) T cells in direct vicinity to the AVN-enriched compartments. The formed mDC-T cell conjugates exhibit strong morphological similarities between the GM3-AVN-containing mDC-T cell synapse and the HIV-1 virological synapse, indicating that GM3-CD169 interactions alone are sufficient for establishing the mDC-T cell virological synapse. These results emphasize the potential of the GM3-AVN approach for providing therapeutic access to a key step of the host immune response--formation of the synaptic junction between an antigen-presenting cell (mDC) and T cells--for modulating and controlling immune responses.

  17. COMPUTED TOMOGRAPHIC AND ULTRASONOGRAPHIC CHARACTERISTICS OF CAVERNOUS TRANSFORMATION OF THE OBSTRUCTED PORTAL VEIN IN SMALL ANIMALS.

    PubMed

    Specchi, Swan; Pey, Pascaline; Ledda, Gianluca; Lustgarten, Meghann; Thrall, Donald; Bertolini, Giovanna

    2015-01-01

    In humans, the process of development of collateral vessels with hepatopetal flow around the portal vein in order to bypass an obstruction is called "cavernous transformation of the portal vein." The purpose of this retrospective, cross-sectional, multicentric study was to describe presumed cavernous transformation of the portal vein in small animals with portal vein obstruction using ultrasound and multidetector-row computed tomography (MDCT). Databases from three different institutions were searched for patients with an imaging diagnosis of cavernous transformation of the portal vein secondary to portal vein obstruction of any cause. Images were retrieved and reanalyzed. With MDCT-angiography, two main portoportal collateral pathways were identified: short tortuous portoportal veins around/inside the thrombus and long portoportal collaterals bypassing the site of portal obstruction. Three subtypes of the long collaterals, often coexisting, were identified. Branches of the hepatic artery where involved in collateral circulation in nine cases. Concomitant acquired portosystemic shunts were identified in six patients. With ultrasound, cavernous transformation of the portal vein was suspected in three dogs and one cat based on visualization of multiple and tortuous vascular structures corresponding to periportal collaterals. In conclusion, the current study provided descriptive MDCT and ultrasonographic characteristics of presumed cavernous transformation of the portal vein in a sample of small animals. Cavernous transformation of the portal vein could occur as a single condition or could be concurrent with acquired portosystemic shunts. PMID:25877678

  18. Method for transforming CT images for attenuation correction in PET/CT imaging

    SciTech Connect

    Carney, Jonathan P.J.; Townsend, David W.; Rappoport, Vitaliy; Bendriem, Bernard

    2006-04-15

    A tube-voltage-dependent scheme is presented for transforming Hounsfield units (HU) measured by different computed tomography (CT) scanners at different x-ray tube voltages (kVp) to 511 keV linear attenuation values for attenuation correction in positron emission tomography (PET) data reconstruction. A Gammex 467 electron density CT phantom was imaged using a Siemens Sensation 16-slice CT, a Siemens Emotion 6-slice CT, a GE Lightspeed 16-slice CT, a Hitachi CXR 4-slice CT, and a Toshiba Aquilion 16-slice CT at kVp ranging from 80 to 140 kVp. All of these CT scanners are also available in combination with a PET scanner as a PET/CT tomograph. HU obtained for various reference tissue substitutes in the phantom were compared with the known linear attenuation values at 511 keV. The transformation, appropriate for lung, soft tissue, and bone, yields the function 9.6x10{sup -5}{center_dot}(HU+1000) below a threshold of {approx}50 HU and a{center_dot}(HU+1000)+b above the threshold, where a and b are fixed parameters that depend on the kVp setting. The use of the kVp-dependent scaling procedure leads to a significant improvement in reconstructed PET activity levels in phantom measurements, resolving errors of almost 40% otherwise seen for the case of dense bone phantoms at 80 kVp. Results are also presented for patient studies involving multiple CT scans at different kVp settings, which should all lead to the same 511 keV linear attenuation values. A linear fit to values obtained from 140 kVp CT images using the kVp-dependent scaling plotted as a function of the corresponding values obtained from 80 kVp CT images yielded y=1.003x-0.001 with an R{sup 2} value of 0.999, indicating that the same values are obtained to a high degree of accuracy.

  19. Comparison of 64-Detector CT Colonography and Conventional Colonoscopy in the Detection of Colorectal Lesions

    PubMed Central

    Devir, Cigdem; Kebapci, Mahmut; Temel, Tuncer; Ozakyol, Aysegul

    2016-01-01

    Background: Colon cancer is a leading cause of morbidity and mortality in developed countries. The early detection of colorectal cancer using screening programs is important for managing early-stage colorectal cancers and polyps. Modalities that allow examination of the entire colon are conventional colonoscopy, double contrast barium enema examination and multi-detector computed tomography (MDCT) colonography. Objectives: To compare CT colonography and conventional colonoscopy results and to evaluate the accuracy of CT colonography for detecting colorectal lesions. Patients and Methods: In a prospective study performed at Gastroenterology and Radiology Departments of Medical Faculty of Eskisehir Osmangazi University, CT colonography and colonoscopy results of 31 patients with family history of colorectal carcinoma, personal or family history of colorectal polyps, lower gastrointestinal tract bleeding, change in bowel habits, iron deficiency anemia and abdominal pain were compared. Regardless of the size, CT colonography and conventional colonoscopy findings for all the lesions were cross - tabulated and the sensitivity, specificity, and positive and negative predictive values were calculated. To assess the agreement between CT colonography and conventional colonoscopy examinations, the Kappa coefficient of agreementt was used. Statistical analysis was performed by SPSS ver 15.0. Results: Regardless of the size, MDCT colonography showed 83% sensitivity and 95% specificity, with a positive predictive value of 95% and a negative predictive value of 83% for the detection of colorectal polyps and masses. MDCT colonography displayed 92% sensitivity and 95% specificity, with a positive predictive value of 92% and a negative predictive value of 95% for polyps ≥ 10 mm. For polyps between 6mm and 9 mm, MDCT colonography displayed 75% sensitivity and 100% specificity, with a positive predictive value of 100% and a negative predictive value of 90%. For polyps ≤ 5 mm MDCT

  20. [Multidetector CT and magnetic resonance imaging features of solitary fibrous tumors in the pelvis and the relevant pathologic basis changes].

    PubMed

    Li, Xueming; Ren, Jing; Zhou, Peng; Cao, Ying; Cheng, Zhuzhong; Yu, Jianqun; Xu, Guohui

    2015-02-01

    In order to investigate the features of multidetector CT (MDCT) and magnetic resonance imaging (MRI) as well as the corresponding pathogic basis of solitary fibrous tumor (SFT) in the pelvis, we collected the clinical data of 13 patients with pathologically confirmed SFT in pelvis, and retrospectively reviewed the MDCT and MRI appearances. Of these enrolled patients, 6 received MDCT scans, 5 underwent MRI scans, and 2 underwent both MDCT and MRI examinations. Shown on the MDCT and MRI, the maximum diameters of the masses ranged from 4.0 to 25.2 cm (averaged 11.8 cm). Six masses were lobulated, and seven were round or oval. In addition, all masses were well-defined and displaced the adjacent structures to some degrees. On the computed tomography, all masses were of isodensity on unenhanced scans in general, among which five masses were demonstrated with hypodense areas. On the MRI T1-weighted image, all lesions were isointense, of which patchy hypointense areas were detected in 3 cases and radial hypointense areas were in 3 cases, and the other one was presented with homogenous intensity. On T2-weighted images, most of the lesions were mixed hyperintense, of which 3 cases were of heterogenous hyperintesity, radial hypointense areas were detected in 3 patients, and the other one was homogenously intense. On enhanced computed tomography and MRI, large supplying vessels were found in 4 cases; 12 cases showed moderate to conspicuous enhancement, and the other one was presented with mild homogenous enhancement. Of the patients with moderate to conspicuous enhancement, patchy areas of non-enhancement were detected in 7 cases, radial areas of progressive enhancement were detected in 3 cases, and the remained 2 cases showed homogenous enhancement. On pathology, the radial area presented as progressive enhancement was fibrosis. During the follow-ups after surgery, 2 patients had local recurrence and 1 had metastasis to liver. In conclusion, the SFT in the pelvis are commonly

  1. [Multidetector CT and magnetic resonance imaging features of solitary fibrous tumors in the pelvis and the relevant pathologic basis changes].

    PubMed

    Li, Xueming; Ren, Jing; Zhou, Peng; Cao, Ying; Cheng, Zhuzhong; Yu, Jianqun; Xu, Guohui

    2015-02-01

    In order to investigate the features of multidetector CT (MDCT) and magnetic resonance imaging (MRI) as well as the corresponding pathogic basis of solitary fibrous tumor (SFT) in the pelvis, we collected the clinical data of 13 patients with pathologically confirmed SFT in pelvis, and retrospectively reviewed the MDCT and MRI appearances. Of these enrolled patients, 6 received MDCT scans, 5 underwent MRI scans, and 2 underwent both MDCT and MRI examinations. Shown on the MDCT and MRI, the maximum diameters of the masses ranged from 4.0 to 25.2 cm (averaged 11.8 cm). Six masses were lobulated, and seven were round or oval. In addition, all masses were well-defined and displaced the adjacent structures to some degrees. On the computed tomography, all masses were of isodensity on unenhanced scans in general, among which five masses were demonstrated with hypodense areas. On the MRI T1-weighted image, all lesions were isointense, of which patchy hypointense areas were detected in 3 cases and radial hypointense areas were in 3 cases, and the other one was presented with homogenous intensity. On T2-weighted images, most of the lesions were mixed hyperintense, of which 3 cases were of heterogenous hyperintesity, radial hypointense areas were detected in 3 patients, and the other one was homogenously intense. On enhanced computed tomography and MRI, large supplying vessels were found in 4 cases; 12 cases showed moderate to conspicuous enhancement, and the other one was presented with mild homogenous enhancement. Of the patients with moderate to conspicuous enhancement, patchy areas of non-enhancement were detected in 7 cases, radial areas of progressive enhancement were detected in 3 cases, and the remained 2 cases showed homogenous enhancement. On pathology, the radial area presented as progressive enhancement was fibrosis. During the follow-ups after surgery, 2 patients had local recurrence and 1 had metastasis to liver. In conclusion, the SFT in the pelvis are commonly

  2. A method to generate equivalent energy spectra and filtration models based on measurement for multidetector CT Monte Carlo dosimetry simulations.

    PubMed

    Turner, Adam C; Zhang, Di; Kim, Hyun J; DeMarco, John J; Cagnon, Chris H; Angel, Erin; Cody, Dianna D; Stevens, Donna M; Primak, Andrew N; McCollough, Cynthia H; McNitt-Gray, Michael F

    2009-06-01

    The purpose of this study was to present a method for generating x-ray source models for performing Monte Carlo (MC) radiation dosimetry simulations of multidetector row CT (MDCT) scanners. These so-called "equivalent" source models consist of an energy spectrum and filtration description that are generated based wholly on the measured values and can be used in place of proprietary manufacturer's data for scanner-specific MDCT MC simulations. Required measurements include the half value layers (HVL1 and HVL2) and the bowtie profile (exposure values across the fan beam) for the MDCT scanner of interest. Using these measured values, a method was described (a) to numerically construct a spectrum with the calculated HVLs approximately equal to those measured (equivalent spectrum) and then (b) to determine a filtration scheme (equivalent filter) that attenuates the equivalent spectrum in a similar fashion as the actual filtration attenuates the actual x-ray beam, as measured by the bowtie profile measurements. Using this method, two types of equivalent source models were generated: One using a spectrum based on both HVL1 and HVL2 measurements and its corresponding filtration scheme and the second consisting of a spectrum based only on the measured HVL1 and its corresponding filtration scheme. Finally, a third type of source model was built based on the spectrum and filtration data provided by the scanner's manufacturer. MC simulations using each of these three source model types were evaluated by comparing the accuracy of multiple CT dose index (CTDI) simulations to measured CTDI values for 64-slice scanners from the four major MDCT manufacturers. Comprehensive evaluations were carried out for each scanner using each kVp and bowtie filter combination available. CTDI experiments were performed for both head (16 cm in diameter) and body (32 cm in diameter) CTDI phantoms using both central and peripheral measurement positions. Both equivalent source model types result in

  3. Automated cortical bone segmentation for multirow-detector CT imaging with validation and application to human studies

    PubMed Central

    Li, Cheng; Jin, Dakai; Chen, Cheng; Letuchy, Elena M.; Janz, Kathleen F.; Burns, Trudy L.; Torner, James C; Levy, Steven M.; Saha, Punam K

    2015-01-01

    Purpose: Cortical bone supports and protects human skeletal functions and plays an important role in determining bone strength and fracture risk. Cortical bone segmentation at a peripheral site using multirow-detector CT (MD-CT) imaging is useful for in vivo assessment of bone strength and fracture risk. Major challenges for the task emerge from limited spatial resolution, low signal-to-noise ratio, presence of cortical pores, and structural complexity over the transition between trabecular and cortical bones. An automated algorithm for cortical bone segmentation at the distal tibia from in vivo MD-CT imaging is presented and its performance and application are examined. Methods: The algorithm is completed in two major steps—(1) bone filling, alignment, and region-of-interest computation and (2) segmentation of cortical bone. After the first step, the following sequence of tasks is performed to accomplish cortical bone segmentation—(1) detection of marrow space and possible pores, (2) computation of cortical bone thickness, detection of recession points, and confirmation and filling of true pores, and (3) detection of endosteal boundary and delineation of cortical bone. Effective generalizations of several digital topologic and geometric techniques are introduced and a fully automated algorithm is presented for cortical bone segmentation. Results: An accuracy of 95.1% in terms of volume of agreement with manual outlining of cortical bone was observed in human MD-CT scans, while an accuracy of 88.5% was achieved when compared with manual outlining on postregistered high resolution micro-CT imaging. An intraclass correlation coefficient of 0.98 was obtained in cadaveric repeat scans. A pilot study was conducted to describe gender differences in cortical bone properties. This study involved 51 female and 46 male participants (age: 19–20 yr) from the Iowa Bone Development Study. Results from this pilot study suggest that, on average after adjustment for height

  4. Cavernous Transformation of the Portal Vein Might Increase the Risk of Liver Abscess

    PubMed Central

    Ai, Xin-Bo; Gong, Fei-Yue; Wang, An; Liang, Hua-Min; Pan, Wen-Sheng

    2010-01-01

    Cavernous transformation of the portal vein (CTPV) is not quite common in adults, and cases with CTPV and acute liver abscess are lacking. We report a patient with CTPV inducing extrahepatic and intrahepatic obstruction, finally leading to acute liver abscess due to bile duct infection. We aim to find out the possible relationship between CTPV and acute liver abscess. A 45-year-old female patient was admitted to our hospital for recurrent upper abdominal pain and distension for one year, aggravated with fever for three years. A diagnosis of CTPV and liver abscess was made by 16-slice computed tomography. Effective antibiotics and drainage were used for this patients, and she was eventually cured. When treating patients with CTPV, extrahepatic and intrahepatic obstruction, one should be aware of the presence of acute liver abscess, and empirical antibiotics might be valuable. PMID:21060692

  5. Comparison of accuracy of 64-slice cardiovascular computed tomography with coronary angiography in patients with suspected coronary artery disease.

    PubMed

    Fine, Jeffrey J; Hopkins, Christie B; Ruff, Nicol; Newton, F Carter

    2006-01-15

    Cardiovascular computed tomography (CVCT) with the recently released 64-slice technology increases spatial resolution and decreases acquisition times and slice thickness. We investigated the accuracy of 64-slice CVCT in relation to catheter angiography. We studied 66 sequential subjects who underwent 64-slice CVCT and catheter angiography within 30 days. Accuracy results were 94% for interpretable images, 95% for sensitivity, 96% for specificity, 97% for positive predictive value, and 92% for negative predictive value for lesions with >50% stenosis. We found 100% agreement between 64-slice CVCT and catheterization among vein graft evaluations (9 of 9). These metrics are vastly improved from the 16-slice generation and support 64-slice CVCT as a reliable diagnostic tool.

  6. Tilted helical Feldkamp cone-beam reconstruction algorithm for multislice CT

    NASA Astrophysics Data System (ADS)

    Hein, Ilmar A.; Taguchi, Katsuyuki; Mori, Issei; Kazama, Masahiro; Silver, Michael D.

    2003-05-01

    In many clinical applications, it is necessary to tilt the gantry of an X-ray CT system with respect to the patient. Tilting the gantry introduces no complications for single-slice fan-beam systems; however, most systems today are helical multislice systems with up to 16 slices (and this number is sure to increase in the future). The image reconstruction algorithms used in multislice helical CT systems must be modified to compensate for the tilt. If they are not, the quality of reconstructed images will be poor with the presence of significant artifacts produced by the tilt. Practical helical multislice algorithms currently incorporated in today"s systems include helical fan-beam, ASSR (Advanced single-slice rebinning), and Feldkamp algorithms. This paper presents the modifications necessary to compensate for gantry tilt for the helical cone-beam Feldkamp algorithm implemented by Toshiba (referred to as TCOT for true cone-beam tomography). Unlike some of the other algorithms, gantry tilt compensation is simple and straightforward to implement with no significant increase in computational complexity. It will be shown that the effect of the gantry tilt is to introduce a lateral shift in the isocenter of the reconstructed slice of interest, which is a function of the tilt, couch speed, and view angle. This lateral shift is easily calculated and incorporated into the backprojection algorithm. The tilt-compensated algorithm is called T-TCOT. Experimental tilted-gantry data has been obtained with 8- and 16 slice Toshiba Aquilion systems, and examples of uncompensated and tilt compensated images are presented.

  7. Model-based cartilage thickness measurement in the submillimeter range

    SciTech Connect

    Streekstra, G. J.; Strackee, S. D.; Maas, M.; Wee, R. ter; Venema, H. W.

    2007-09-15

    Current methods of image-based thickness measurement in thin sheet structures utilize second derivative zero crossings to locate the layer boundaries. It is generally acknowledged that the nonzero width of the point spread function (PSF) limits the accuracy of this measurement procedure. We propose a model-based method that strongly reduces PSF-induced bias by incorporating the PSF into the thickness estimation method. We estimated the bias in thickness measurements in simulated thin sheet images as obtained from second derivative zero crossings. To gain insight into the range of sheet thickness where our method is expected to yield improved results, sheet thickness was varied between 0.15 and 1.2 mm with an assumed PSF as present in the high-resolution modes of current computed tomography (CT) scanners [full width at half maximum (FWHM) 0.5-0.8 mm]. Our model-based method was evaluated in practice by measuring layer thickness from CT images of a phantom mimicking two parallel cartilage layers in an arthrography procedure. CT arthrography images of cadaver wrists were also evaluated, and thickness estimates were compared to those obtained from high-resolution anatomical sections that served as a reference. The thickness estimates from the simulated images reveal that the method based on second derivative zero crossings shows considerable bias for layers in the submillimeter range. This bias is negligible for sheet thickness larger than 1 mm, where the size of the sheet is more than twice the FWHM of the PSF but can be as large as 0.2 mm for a 0.5 mm sheet. The results of the phantom experiments show that the bias is effectively reduced by our method. The deviations from the true thickness, due to random fluctuations induced by quantum noise in the CT images, are of the order of 3% for a standard wrist imaging protocol. In the wrist the submillimeter thickness estimates from the CT arthrography images correspond within 10% to those estimated from the anatomical

  8. [Computer tomography of sports injuries].

    PubMed

    Reiser, M; Rupp, N

    1984-01-01

    Computed tomography (CT) provides axial slices plane and shows excellent details of bones and different soft tissues, favoring its use in traumatic lesions caused by sporting activities. Complex anatomical structures such as the shoulder, the vertebral column, the pelvis, the knee, the tarsal and carpal bones are often better recognized in detail than by conventional radiography. Fracture lines, localization of bone fragments and involvement of soft tissues are clearly demonstrated. Luxations and bone changes leading to luxations can be shown. CT arthrography provides for the first time a direct visualization of joint cartilage and of cruciate ligaments in the knee joint, so traumatic lesions such as chondropathia patellae or rupture of the cruciate ligaments are shown with a high degree of reliability.

  9. The knee: Surface-coil MR imaging at 1. 5 T

    SciTech Connect

    Beltran, J.; Noto, A.M.; Mosure, J.C.; Weiss, K.L.; Zuelzer, W.; Christoforidis, A.J.

    1986-06-01

    Seven normal knees (in five volunteers) and seven injured knees (in seven patients) were examined by high-resolution magnetic resonance (MR) imaging at 1.5 T with a surface coil. Seven medial meniscal tears, three anterior cruciate ligament tears, one posterior cruciate ligament avulsion, an old osteochondral fracture, femoral condylar chondro-malacia, and one case of semimembranous tendon reinsertion were identified. MR images correlated well with recent double-contrast arthrograms or results of surgery. All tears were identified in both the sagittal and coronal planes. Because of its ability to demonstrate small meniscal lesions and ligamentous injuries readily, MR imaging with a surface coil may eventually replace the more invasive arthrography.

  10. Arthroscopic capsule reconstruction in the hip using iliotibial band allograft.

    PubMed

    Trindade, Christiano A C; Sawyer, Gregory A; Fukui, Kiyokazu; Briggs, Karen K; Philippon, Marc J

    2015-02-01

    The hip capsule has been identified as an important static stabilizer of the hip joint. Despite the intrinsic bony stability of the hip socket, the capsule plays a key role in hip stability, particularly at the extremes of motion, and the iliofemoral ligament is the most important stabilizer in extension and external rotation. Patients who do not undergo capsular closure or plication may continue to complain of hip pain and dysfunction postoperatively, likely because of microinstability or muscle invagination into the capsular defect, and high-resolution magnetic resonance imaging or magnetic resonance arthrography will identify the capsular defect. Seen primarily in the revision setting, capsular defects can cause recurrent stress at the chondrolabral junction. An attempt at secondary closure can be challenging because of capsular limb adherence to the surrounding soft tissues. Therefore reconstruction may be the only possible surgical solution for this problem. We describe our new surgical technique for arthroscopic hip capsular reconstruction using iliotibial band allograft.

  11. Arthroscopic capsule reconstruction in the hip using iliotibial band allograft.

    PubMed

    Trindade, Christiano A C; Sawyer, Gregory A; Fukui, Kiyokazu; Briggs, Karen K; Philippon, Marc J

    2015-02-01

    The hip capsule has been identified as an important static stabilizer of the hip joint. Despite the intrinsic bony stability of the hip socket, the capsule plays a key role in hip stability, particularly at the extremes of motion, and the iliofemoral ligament is the most important stabilizer in extension and external rotation. Patients who do not undergo capsular closure or plication may continue to complain of hip pain and dysfunction postoperatively, likely because of microinstability or muscle invagination into the capsular defect, and high-resolution magnetic resonance imaging or magnetic resonance arthrography will identify the capsular defect. Seen primarily in the revision setting, capsular defects can cause recurrent stress at the chondrolabral junction. An attempt at secondary closure can be challenging because of capsular limb adherence to the surrounding soft tissues. Therefore reconstruction may be the only possible surgical solution for this problem. We describe our new surgical technique for arthroscopic hip capsular reconstruction using iliotibial band allograft. PMID:25973378

  12. Giant intraosseous cyst-like lesions in rheumatoid arthritis report of a case.

    PubMed

    Lohse, Anne; Carbillet, Jean-Pierre; Onimus, Michel; Stevenel, Françoise; Toussirot, Eric; Wendling, Daniel

    2003-02-01

    The term "intraosseous synovial cyst" is used to designate both the epiphyseal cyst-like lesions seen in patients with rheumatoid arthritis (RA) and mucoid cysts, which occur in a different setting. We report the case of a patient in whom a 4-cm cyst-like lesion developed in the left tibia 18 years after onset of RA and 6 years after osmic acid synovectomy of the left knee. Positive contrast arthrography and magnetic resonance imaging visualized a communication between the lesion and the joint space. Preexisting bone and joint lesions and increased intraarticular pressure play a major role in the genesis of cyst-like lesions in RA. In our patient, the osmic acid synovectomy may have contributed to the development of the lesion. "Synovial cyst" is a misnomer for these giant lesions, which are geodes rather than cysts. Despite their low incidence, these lesions deserve attention because they raise diagnostic and therapeutic problems.

  13. Beyond the Cuff: MR Imaging of Labroligamentous Injuries in the Athletic Shoulder.

    PubMed

    Roy, Elizabeth A; Cheyne, Ian; Andrews, Gordon T; Forster, Bruce B

    2016-02-01

    Shoulder disease is common in the athletic population and may arise as a consequence of a single traumatic episode or multiple repeated events. Associated labroligamentous injuries can result in substantial disability. Specific athletic and occupational activities result in predictable injury patterns. Imaging in general and magnetic resonance (MR) imaging, in particular, are vital in establishing the correct diagnosis and excluding common mimicking conditions, to ensure timely and appropriate management. In this review, the utility of MR imaging and MR arthrography will be explored in evaluation of shoulder disease, taking into account normal variants of the labroligamentous complex. Subsequently, broad categories of labral lesions and instability, external and internal impingement, as well as nerve entrapment syndromes, will be discussed, while emphasizing their imaging findings in the clinical context and illustrating key features. More recent concepts of internal impingement and secondary subacromial impingement will also be clarified.

  14. Rotator cuff disorders: How to write a surgically relevant magnetic resonance imaging report?

    PubMed

    Tawfik, Ahmed M; El-Morsy, Ahmad; Badran, Mohamed Aboelnour

    2014-06-28

    Evaluation of rotator cuff is a common indication for magnetic resonance imaging (MRI) scanning of the shoulder. Conventional MRI is the most commonly used technique, while magnetic resonance (MR) arthrography is reserved for certain cases. Rotator cuff disorders are thought to be caused by a combination of internal and external mechanisms. A well-structured MRI report should comment on the relevant anatomic structures including the acromial type and orientation, the presence of os acromiale, acromio-clavicular degenerative spurs and fluid in the subacromial subdeltoid bursa. In addition, specific injuries of the rotator cuff tendons and the condition of the long head of biceps should be accurately reported. The size and extent of tendon tears, tendon retraction and fatty degeneration or atrophy of the muscles are all essential components of a surgically relevant MRI report.

  15. Closed rupture of the flexor tendons caused by carpal bone and joint disorders.

    PubMed

    Yamazaki, H; Kato, H; Hata, Y; Nakatsuchi, Y; Tsuchikane, A

    2007-12-01

    We analysed 21 patients with closed rupture of the flexor tendons caused by carpal bone and joint disorders. The tendon that ruptured depended on the location of the bone perforation into the carpal tunnel. Radiocarpal arthrography was performed in 13 patients and capsular perforation was demonstrated by contrast medium leakage into the carpal canal in 11 patients. This proved a useful diagnostic test. The flexor tendon(s) were reconstructed with free tendon graft in 17 patients, cross-over transfer of flexor tendons from adjacent digits in two and buddying to an adjacent flexor tendon in one patient. Postoperative total active range of motion in the fingers after 13 free tendon graft reconstructions averaged 213 degrees (range 170-265 degrees ). The active range of motion of the thumb-interphalangeal joint after free tendon graft reconstruction in three cases improved from 0 degrees to 33 degrees on average (range 10 degrees -40 degrees ).

  16. Prospective study of sequential technetium-99m phosphate and gallium imaging in painful hip prostheses (comparison of diagnostic modalities)

    SciTech Connect

    Tehranzadeh, J.; Gubernick, I.; Blaha, D.

    1988-04-01

    Twenty-two painful hip prostheses were studied prospectively with plain radiography, aspiration and arthrography, Tc-99m phosphate bone imaging, and gallium imaging to evaluate loosening, infection, or both and to compare the accuracy of these modalities. Fifteen prostheses were revised yielding 14 loose femoral and eight loose acetabular components. Five proved to have infected prostheses. Arthrograms, plain radiographs, and bone scans are highly sensitive in detecting loosening of the femoral component. This study confirmed a previous retrospective study in demonstrating that accuracy of diagnosis of an abnormal acetabular component using all four modalities is less than that for the femoral component. In infected prostheses, phosphate bone imaging showed high sensitivity of a pattern that accurately diagnosed all the infected cases, whereas gallium imaging missed one case.

  17. Arthroscopy of the wrist: anatomy and classification of carpal instability.

    PubMed

    Cooney, W P; Dobyns, J H; Linscheid, R L

    1990-01-01

    Carpal instability can be defined as the lack of ligamentous and skeletal support adequate to maintain a wrist stable to external forces of pinch and grasp. This instability may be static or dynamic. It has been classified as (a) carpal instability, dissociated (CID), a situation in which one or more of the ligaments are torn, and (b) carpal instability, nondissociative (CIND), a situation in which the ligaments are intact but stretched. Carpal instability can also be the result of carpal bone malalignment from various causes. Arthroscopy can be particularly useful in assessing carpal instability, however arthrography with contrast medium, fluoroscopy, and stress loading should precede this arthroscopic assessment. Arthroscopy allows visualization of the volar radiocarpal and ulnocarpal ligaments of the wrist, and the arthroscopic examination can be combined with manual manipulation of the carpal bones to detect laxity of those ligaments, to examine stability of the scapholunate and lunotriquetral interosseous ligaments, and to show instability of the distal radioulnar joint.

  18. [Early radiological diagnostics for scapholunate dissociation (SLD)].

    PubMed

    Schmitt, R; Fröhner, S; Fodor, S; Christopoulos, G; Kalb, K H

    2006-08-01

    The partial tear of the scapholunate ligament (pre-dynamic stage of SLD) as well as the complete tear (dynamic stage) does not lead to carpal malalignment. However, if the completely ruptured ligament is accompanied by lesions of the extrinsic ligaments, both the scaphoid and the lunate are malaligned already at rest (static stage of SLD). Later, osteoarthritis will develop, beginning in the radioscaphoid compartment, progressing to the midcarpal joint, and ending in a carpal collapse (osteoarthrotic stage of SLD). Dynamic SLD is detectable only in stress views and in cinematography. The high utility of MRI for directly visualizing the injured ligament is emphasized: reparation tissue is focally enhanced at the rupture site by intravenously applied contrast agent; the individual segments of the scapholunate ligament can be visualized in direct MR arthrography, therefore allowing differentiation of partial and complete ligamentous tears. PMID:16874503

  19. Imaging Algorithms for Evaluating Suspected Rotator Cuff Disease: Society of Radiologists in Ultrasound Consensus Conference Statement

    PubMed Central

    Jacobson, Jon A.; Benson, Carol B.; Bancroft, Laura W.; Bedi, Asheesh; McShane, John M.; Miller, Theodore T.; Parker, Laurence; Smith, Jay; Steinbach, Lynne S.; Teefey, Sharlene A.; Thiele, Ralf G.; Tuite, Michael J.; Wise, James N.; Yamaguchi, Ken

    2013-01-01

    The Society of Radiologists in Ultrasound convened a panel of specialists from a variety of medical disciplines to reach a consensus about the recommended imaging evaluation of painful shoulders with clinically suspected rotator cuff disease. The panel met in Chicago, Ill, on October 18 and 19, 2011, and created this consensus statement regarding the roles of radiography, ultrasonography (US), computed tomography (CT), CT arthrography, magnetic resonance (MR) imaging, and MR arthrography. The consensus panel consisted of two co-moderators, a facilitator, a statistician and health care economist, and 10 physicians who have specialty expertise in shoulder pain evaluation and/or treatment. Of the 13 physicians on the panel, nine were radiologists who were chosen to represent a broad range of skill sets in diagnostic imaging, different practice types (private and academic), and different geographical regions of the United States. Five of the radiologists routinely performed musculoskeletal US as part of their practice and four did not. There was also one representative from each of the following clinical specialties: rheumatology, physical medicine and rehabilitation, orthopedic surgery, and nonoperative sports medicine. The goal of this conference was to construct several algorithms with which to guide the imaging evaluation of suspected rotator cuff disease in patients with a native rotator cuff, patients with a repaired rotator cuff, and patients who have undergone shoulder replacement. The panel hopes that these recommendations will lead to greater uniformity in rotator cuff imaging and more cost-effective care for patients suspected of having rotator cuff abnormality. © RSNA, 2013 PMID:23401583

  20. [Study of anatomy of the lateral attachment of the renal fascia in adult with multidetector computed tomography].

    PubMed

    Qi, Rui; Zhou, Xianping; Yu, Jianqun; Chen, Weixia; Li, Zhenlin; Zhang, Chunle

    2012-08-01

    The present paper is aimed to observe the lateral attachment of the renal fascia (RF) in vivo with multidetector computed tomography (MDCT) scanning, and to discuss its diagnostic value. 121 healthy adults were adopted into this experiment. All images were obtained with MDCT and double phase enhancement scanning. Then we observed the lateral attachment of RF. In addition, we mad a fresh body specimen as anatomical basis. The study found that above the renal hilar plane (RHP), the anterior renal fascia laterally fused with the peritoneum of the liver on the right and the peritoneum of the spleen on the left,and the posterior renal fascia fused with the subdiaphragmatic fascia. The lateral attachment of the RF at the RHP and the lower renal pole(LRP)is divided into three types. The RF in Type I is about 47.9% (58/121) at the left RHP, while about 33.9% (41/121) at the right RHP. At the LRP of the kidney is about 55.3% (67/121) on the left, and about 42.1% (51/121) on the right. The RF in Type I is about 38.8% (47/121) on the left side at the RHP, about 26.4% (32/121) on the right side. At the LRP, left side about 27.3% (33/121), right side about 13.3%(16/121). The RF in Type III at the RHP is 13.3% (16/121) on the left side, and on the right side is about 39.7% (48/121). At the LRP, it is about 17.4% (21/121) on the left side, and about 44.6% (54/121) on the right side. MDCT can display the lateral attachment of the RF better as well as the outside connection of the retroperitoneal space.

  1. Effect of mixing scanner types and reconstruction kernels on the characterization of lung parenchymal pathologies: emphysema, interstitial pulmonary fibrosis and normal non-smokers

    NASA Astrophysics Data System (ADS)

    Xu, Ye; van Beek, Edwin J.; McLennan, Geoffrey; Guo, Junfeng; Sonka, Milan; Hoffman, Eric

    2006-03-01

    In this study we utilize our texture characterization software (3-D AMFM) to characterize interstitial lung diseases (including emphysema) based on MDCT generated volumetric data using 3-dimensional texture features. We have sought to test whether the scanner and reconstruction filter (kernel) type affect the classification of lung diseases using the 3-D AMFM. We collected MDCT images in three subject groups: emphysema (n=9), interstitial pulmonary fibrosis (IPF) (n=10), and normal non-smokers (n=9). In each group, images were scanned either on a Siemens Sensation 16 or 64-slice scanner, (B50f or B30 recon. kernel) or a Philips 4-slice scanner (B recon. kernel). A total of 1516 volumes of interest (VOIs; 21x21 pixels in plane) were marked by two chest imaging experts using the Iowa Pulmonary Analysis Software Suite (PASS). We calculated 24 volumetric features. Bayesian methods were used for classification. Images from different scanners/kernels were combined in all possible combinations to test how robust the tissue classification was relative to the differences in image characteristics. We used 10-fold cross validation for testing the result. Sensitivity, specificity and accuracy were calculated. One-way Analysis of Variances (ANOVA) was used to compare the classification result between the various combinations of scanner and reconstruction kernel types. This study yielded a sensitivity of 94%, 91%, 97%, and 93% for emphysema, ground-glass, honeycombing, and normal non-smoker patterns respectively using a mixture of all three subject groups. The specificity for these characterizations was 97%, 99%, 99%, and 98%, respectively. The F test result of ANOVA shows there is no significant difference (p <0.05) between different combinations of data with respect to scanner and convolution kernel type. Since different MDCT and reconstruction kernel types did not show significant differences in regards to the classification result, this study suggests that the 3-D AMFM can

  2. Value of liver computed tomography with iodixanol 270, 80 kVp and iterative reconstruction

    PubMed Central

    Botsikas, Diomidis; Barnaure, Isabelle; Terraz, Sylvain; Becker, Christoph D; Kalovidouri, Anastasia; Montet, Xavier

    2016-01-01

    AIM To evaluate the image quality of hepatic multidetector computed tomography (MDCT) with dynamic contrast enhancement. METHODS It uses iodixanol 270 mg/mL (Visipaque 270) and 80 kVp acquisitions reconstructed with sinogram affirmed iterative reconstruction (SAFIRE®) in comparison with a standard MDCT protocol. Fifty-three consecutive patients with known or suspected hepatocellular carcinoma underwent 55 CT examinations, with two different four-phase CT protocols. The first group of 30 patients underwent a standard 120 kVp acquisition after injection of Iohexol 350 mg/mL (Accupaque 350®) and reconstructed with filtered back projection. The second group of 25 patients underwent a dual-energy CT at 80-140 kVp with iodixanol 270. The 80 kVp component of the second group was reconstructed iteratively (SAFIRE®-Siemens). All hyperdense and hypodense hepatic lesions ≥ 5 mm were identified with both protocols. Aorta and portal vessels/liver parenchyma contrast to noise ratio (CNR) in arterial phase, hypervascular lesion/liver parenchyma CNR in arterial phase, hypodense lesion/liver parenchyma CNR in portal and late phase were calculated in both groups. RESULTS Aorta/liver and focal lesions altogether/liver CNR were higher for the second protocol (P = 0.0078 and 0.0346). Hypervascular lesions/liver CNR was not statistically different (P = 0.86). Hypodense lesion/liver CNR in the portal phase was significantly higher for the second group (P = 0.0107). Hypodense lesion/liver CNR in the late phase was the same for both groups (P = 0.9926). CONCLUSION MDCT imaging with 80 kVp with iterative reconstruction and iodixanol 270 yields equal or even better image quality. PMID:27551339

  3. Predicting the biomechanical strength of proximal femur specimens with bone mineral density features and support vector regression

    NASA Astrophysics Data System (ADS)

    Huber, Markus B.; Yang, Chien-Chun; Carballido-Gamio, Julio; Bauer, Jan S.; Baum, Thomas; Nagarajan, Mahesh B.; Eckstein, Felix; Lochmüller, Eva; Majumdar, Sharmila; Link, Thomas M.; Wismüller, Axel

    2012-03-01

    To improve the clinical assessment of osteoporotic hip fracture risk, recent computer-aided diagnosis systems explore new approaches to estimate the local trabecular bone quality beyond bone density alone to predict femoral bone strength. In this context, statistical bone mineral density (BMD) features extracted from multi-detector computed tomography (MDCT) images of proximal femur specimens and different function approximations methods were compared in their ability to predict the biomechanical strength. MDCT scans were acquired in 146 proximal femur specimens harvested from human cadavers. The femurs' failure load (FL) was determined through biomechanical testing. An automated volume of interest (VOI)-fitting algorithm was used to define a consistent volume in the femoral head of each specimen. In these VOIs, the trabecular bone was represented by statistical moments of the BMD distribution and by pairwise spatial occurrence of BMD values using the gray-level co-occurrence (GLCM) approach. A linear multi-regression analysis (MultiReg) and a support vector regression algorithm with a linear kernel (SVRlin) were used to predict the FL from the image feature sets. The prediction performance was measured by the root mean square error (RMSE) for each image feature on independent test sets; in addition the coefficient of determination R2 was calculated. The best prediction result was obtained with a GLCM feature set using SVRlin, which had the lowest prediction error (RSME = 1.040+/-0.143, R2 = 0.544) and which was significantly lower that the standard approach of using BMD.mean and MultiReg (RSME = 1.093+/-0.133, R2 = 0.490, p<0.0001). The combined sets including BMD.mean and GLCM features had a similar or slightly lower performance than using only GLCM features. The results indicate that the performance of high-dimensional BMD features extracted from MDCT images in predicting the biomechanical strength of proximal femur specimens can be significantly improved by

  4. Airway Evaluation with Multidetector Computed Tomography Post-Processing Methods in Asthmatic Patients.

    PubMed

    Patyk, Mateusz; Obojski, Andrzej; Gojny, Łukasz; Panaszek, Bernard; Zaleska-Dorobisz, Urszula

    2016-01-01

    Asthma is a chronic inflammatory obstructive airways disease. The disease occurs regardless of age and manifests with cough, attacks of breathlessness, and tightness in the chest. The pathophysiology of asthma is complex and still not fully understood. It is essential to find answers concerning the role of each part of the bronchial tree in asthma, especially the role of small bronchioles. With the development of newer generations of multidetector computed tomography (MDCT) and advanced post-processing methods it is possible to obtain more detailed images and gain insight into further aspects of asthma. MDCT post-processing methods can be divided into two-dimensional (2D) and three-dimensional (3D). In 2D projections, visualized hypodense regions correspond to the airway flow limitations. With the more advanced methods, such as multi planar reconstructions (MPR), images in different planes (axial, coronal, or sagittal) can be created. In the MPR technique only the voxels which are adjacent to each other in the predetermined plane can be extracted from the data set. Using the minimal/maximal intensity projections and shaded surface display, the volume of interest (VOI) can be extracted. High resolution CT scans can be used to create a more advanced imaging tool - the virtual bronchoscopy (VB). Using the VB makes it possible to visualize regions of obturation in the bronchi of up to the 5-8th generation. The MDCT with advanced post-processing methods is likely to assume an important role in the differential diagnosis of asthma, particularly when the diagnosis is dubious or hard to settle due to accompanying other lung diseases. PMID:27271759

  5. Clinical impact of intraoperative navigation using a Doppler ultrasonographic guided vessel tracking technique for pancreaticoduodenectomy.

    PubMed

    Maemura, Kosei; Mataki, Yuko; Kurahara, Hiroshi; Iino, Satoshi; Sakoda, Masahiko; Ueno, Shinichi; Shinchi, Hiroyuki; Takao, Sonshin; Natsugoe, Shoji

    2014-01-01

    During pancreaticoduodenectomy (PD), early ligation of critical vessels such as the inferior pancreaticoduodenal artery (IPDA) has been reported to reduce blood loss. Color Doppler flow imaging has become the useful diagnostic methods for the delineation of the anatomy. In this study, we assessed the utility of the intraoperative Doppler ultrasonography (Dop-US) guided vessel detection and tracking technique (Dop-Navi) for identifying critical arteries in order to reduce operative bleeding. Ninety patients who received PD for periampullary or pancreatic disease were enrolled. After 14 patients were excluded because of combined resection of portal vein or other organs, the remaining were assigned to 1 of 2 groups: patients for whom Dop-Navi was used (n = 37) and those for whom Dop-Navi was not used (n = 39; controls). We compared the ability of Dop-Navi to identify critical vessels to that of preoperative multi-detector computed tomography (MD-CT), using MD-CT data, as well as compared the perioperative status and postoperative outcome between the 2 patient groups. Intraoperative Dop-US was significantly superior to MD-CT in terms of identifying number of vessels and the ability to discriminate the IPDA from the superior mesenteric artery (SMA) based on blood flow velocity. The Dop-Navi patients had shorter operation times (531 min versus 577 min; no significance) and smaller bleeding volumes (1120 mL versus 1590 mL; P < 0.01) than the control patients without increasing postoperative complications. Intraoperative Dop-Navi method allows surgeons to clearly identify the IPDA during PD and to avoid injuries to major arteries. PMID:25437586

  6. Electrocardiogram-Gated 320-Slice Multidetector Computed Tomography for the Measurement of Pulmonary Arterial Distensibility in Chronic Thromboembolic Pulmonary Hypertension

    PubMed Central

    Kasai, Hajime; Sugiura, Toshihiko; Tanabe, Nobuhiro; Sakurai, Yoriko; Yahaba, Misuzu; Matsuura, Yukiko; Shigeta, Ayako; Kawata, Naoko; Sakao, Seiichiro; Kasahara, Yasunori; Tatsumi, Koichiro

    2014-01-01

    Background We aimed to study whether pulmonary arterial distensibility (PAD) correlates with hemodynamic parameters in chronic thromboembolic pulmonary hypertension (CTEPH) using electrocardiogram (ECG)-gated 320-slice multidetector computed tomography (MDCT). Methods and Findings ECG-gated 320-slice MDCT and right heart catheterization (RHC) was performed in 53 subjects (60.6±11.4 years old; 37 females) with CTEPH. We retrospectively measured the minimum and maximum values of the cross sectional area (CSA) of the main pulmonary artery (mainPA), right pulmonary artery (rtPA), and left pulmonary artery (ltPA) during one heartbeat. PAD was calculated using the following formula: PAD = [(CSAmaximum−CSAminimum)/CSAmaximum]×100(%). The correlation between hemodynamic parameters and PAD was assessed. Mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) were 40.8±8.7 mmHg and 8.3±3.0 wood units, respectively. PAD values were as follows: mainPA (14.0±5.0%), rtPA (12.8±5.6%), and ltPA (9.7±4.6%). Good correlations existed between mainPAD, with mPAP (r = −0.594, p<0.001) and PVR (r = −0.659, p<0.001). The correlation coefficients between rtPAD and ltPAD with pulmonary hemodynamics were all lower or equal than for mainPAD. Conclusions PAD measured using ECG-gated 320-slice MDCT correlates with pulmonary hemodynamics in subjects with CTEPH. The mainPA is suitable for PAD measurement. PMID:25365168

  7. Coronary Calcium Scanning in Patients after Adjuvant Radiation for Early Breast Cancer and Ductal Carcinoma In situ

    PubMed Central

    Chang, Monique; Suh, Jason; Kirtani, Vatsala; Dobrescu, Andrei; Haas, Jonathan; Zeldis, Steven; Shayani, Steven; Hindenburg, Alexander A.

    2013-01-01

    Background and Objective: Radiation therapy (RT) is part of standard adjuvant treatment for breast cancer. Earlier studies demonstrated increased cardiac morbidity and mortality from this. Coronary Calcium scanning utilizing Multidetector Computed Tomography (MDCT) can detect early atherosclerosis in coronary arteries by identifying the amount of calcifications. In our study we employed these tools to detect occult atherosclerosis at least 5 years following breast RT. Methods: We evaluated 20 asymptomatic patients, <60 years old, treated with RT at least 5 years prior to enrollment. Nine received RT to the left and 11 to the right chest wall. The median interval between RT and calcium scan was 8 years. All patients were treated with external beam RT using tangential technique. All patients underwent MDCT to compute volumetric and Agatston calcium scores of the coronary arteries and the aorta. Results: Eleven patients had RT to the right chest wall, and eight had a calcium score of 0, while two had minimally elevated scores and one patient had a significantly elevated score. Meanwhile nine patients had RT to the left chest wall, and seven had a calcium score of 0. None had significantly elevated scores. In the aorta, 11 of 20 patients had a score of 0, while 8 of 20 had minimally elevated scores. Conclusion: In contrast to studies demonstrating increased cardiovascular morbidity, our pilot study did not detect significant occult atherosclerosis using MDCT of the coronaries and aorta of patients assessed five or more years following radiation for treatment of breast cancer. PMID:24093087

  8. Achieving consistent image quality with dose optimization in 64-row multidetector computed tomography prospective ECG gated coronary calcium scoring.

    PubMed

    Pan, Zilai; Pang, Lifang; Li, Jianying; Zhang, Huan; Yang, Wenjie; Ding, Bei; Chai, Weimin; Chen, Kemin; Yao, Weiwu

    2011-04-01

    To evaluate the clinical value of a body mass index (BMI) based tube current (mA) selection method for obtaining consistent image quality with dose optimization in MDCT prospective ECG gated coronary calcium scoring. A formula for selecting mA to achieve desired image quality based on patient BMI was established using a control group (A) of 200 MDCT cardiac patients with a standard scan protocol. One hundred patients in Group B were scanned with this BMI-dependent mA for achieving a desired noise level of 18 HU at 2.5 mm slice thickness. The CTDIvol and image noise on the ascending aorta for the two groups were recorded. Two experienced radiologists quantitatively evaluated the image quality using scores of 1-4 with 4 being the highest. The image quality scores had no statistical difference (P = 0.71) at 3.89 ± 0.32, 3.87 ± 0.34, respectively, for groups A and B of similar BMI. The image noise in Group A had linear relationship with BMI. The image noise in Group B using BMI-dependent mA was independent of BMI with average value of 17.9 HU and smaller deviations for the noise values than in Group A (2.0 vs. 2.9 HU). There was a 35% dose reduction with BMI-dependent mA selection method on average with the lowest effective dose being only 0.35 mSv for patient with BMI of 18.3. A quantitative BMI-based mA selection method in MDCT prospective ECG gated coronary calcium scoring has been proposed to obtain a desired and consistent image quality and provide dose optimization across patient population.

  9. Image Quality of 3rd Generation Spiral Cranial Dual-Source CT in Combination with an Advanced Model Iterative Reconstruction Technique: A Prospective Intra-Individual Comparison Study to Standard Sequential Cranial CT Using Identical Radiation Dose

    PubMed Central

    Wenz, Holger; Maros, Máté E.; Meyer, Mathias; Förster, Alex; Haubenreisser, Holger; Kurth, Stefan; Schoenberg, Stefan O.; Flohr, Thomas; Leidecker, Christianne; Groden, Christoph; Scharf, Johann; Henzler, Thomas

    2015-01-01

    Objectives To prospectively intra-individually compare image quality of a 3rd generation Dual-Source-CT (DSCT) spiral cranial CT (cCT) to a sequential 4-slice Multi-Slice-CT (MSCT) while maintaining identical intra-individual radiation dose levels. Methods 35 patients, who had a non-contrast enhanced sequential cCT examination on a 4-slice MDCT within the past 12 months, underwent a spiral cCT scan on a 3rd generation DSCT. CTDIvol identical to initial 4-slice MDCT was applied. Data was reconstructed using filtered backward projection (FBP) and 3rd-generation iterative reconstruction (IR) algorithm at 5 different IR strength levels. Two neuroradiologists independently evaluated subjective image quality using a 4-point Likert-scale and objective image quality was assessed in white matter and nucleus caudatus with signal-to-noise ratios (SNR) being subsequently calculated. Results Subjective image quality of all spiral cCT datasets was rated significantly higher compared to the 4-slice MDCT sequential acquisitions (p<0.05). Mean SNR was significantly higher in all spiral compared to sequential cCT datasets with mean SNR improvement of 61.65% (p*Bonferroni0.05<0.0024). Subjective image quality improved with increasing IR levels. Conclusion Combination of 3rd-generation DSCT spiral cCT with an advanced model IR technique significantly improves subjective and objective image quality compared to a standard sequential cCT acquisition acquired at identical dose levels. PMID:26288186

  10. Computer simulations to estimate organ doses from clinically validated cardiac, neuro, and pediatric protocols for multiple detector computed tomography scanners

    NASA Astrophysics Data System (ADS)

    Ghita, Monica

    Recent advances in Computed Tomography (CT) technology, particularly that of multiple detector CT (MDCT) scanning, have provided increased utilization and more diverse clinical applications including more advanced vascular and cardiac exams, perfusion imaging, and screening exams. Notwithstanding the benefits to the patient undergoing a CT study, the fundamental concern in radiation protection is the minimization of the radiation exposure delivered as well as the implementation of structures to prevent inappropriate ordering and clinical use of these advanced studies. This research work developed a computational methodology for routine clinical use to assess patient organ doses from MDCT scanners. To support the methodology, a computer code (DXS-Diagnostic X-ray Spectra) was developed to accurately and conveniently generate x-ray spectra in the diagnostic energy range (45-140 keV). The two accepted standard radiation transport calculation methods namely, deterministic and Monte Carlo, have been preliminarily investigated for their capability and readiness to support the proposed goal of the work. Thorough tests demonstrated that the lack of appropriate discrete photon interaction coefficients in the aforementioned diagnostic energy range impedes the applicability of the deterministic approach to routine clinical use; improvements in the multigroup treatment may make it more viable. Thus, the open source Monte Carlo code, MCNP5, was adapted to appropriately model an MDCT scan. For this, a new method, entirely based on routine clinical CT measurements, was developed and validated to generate an "equivalent source and filtration" model that obviates the need of proprietary information for a given CT scanner. Computer simulations employing the Monte Carlo methodology and UF's tomographic human phantoms were performed to assess, compare, and optimize pediatric, cardiac and neuro-imaging protocols for the new 320-slice scanner at Shands/UF based on dose considerations

  11. P2Y2 receptor activation inhibits the expression of the sodium-chloride cotransporter NCC in distal convoluted tubule cells.

    PubMed

    Gailly, P; Szutkowska, M; Olinger, E; Debaix, H; Seghers, F; Janas, S; Vallon, V; Devuyst, O

    2014-11-01

    Luminal nucleotide stimulation is known to reduce Na(+) transport in the distal nephron. Previous studies suggest that this mechanism may involve the thiazide-sensitive Na(+)-Cl(-) cotransporter (NCC), which plays an essential role in NaCl reabsorption in the cells lining the distal convoluted tubule (DCT). Here we show that stimulation of mouse DCT (mDCT) cells with ATP or UTP promoted Ca(2+) transients and decreased the expression of NCC at both mRNA and protein levels. Specific siRNA-mediated silencing of P2Y2 receptors almost completely abolished ATP/UTP-induced Ca(2+) transients and significantly reduced ATP/UTP-induced decrease of NCC expression. To test whether local variations in the intracellular Ca(2+) concentration ([Ca(2+)]i) may control NCC transcription, we overexpressed the Ca(2+)-binding protein parvalbumin selectively in the cytosol or in the nucleus of mDCT cells. The decrease in NCC mRNA upon nucleotide stimulation was abolished in cells overexpressing cytosolic PV but not in cells overexpressing either a nuclear-targeted PV or a mutated PV unable to bind Ca(2+). Using a firefly luciferase reporter gene strategy, we observed that the activity of NCC promoter region from -1 to -2,200 bp was not regulated by changes in [Ca(2+)]i. In contrast, high cytosolic calcium level induced instability of NCC mRNA. We conclude that in mDCT cells: (1) P2Y2 receptor is essential for the intracellular Ca(2+) signaling induced by ATP/UTP stimulation; (2) P2Y2-mediated increase of cytoplasmic Ca(2+) concentration down-regulates the expression of NCC; (3) the decrease of NCC expression occurs, at least in part, via destabilization of its mRNA.

  12. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies

    NASA Astrophysics Data System (ADS)

    Murase, Kenya; Nanjo, Takafumi; Satoshi, Ii; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-11-01

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation × 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current.

  13. Reproducibility of Abdominal Aortic Aneurysm Diameter Measurement and Growth Evaluation on Axial and Multiplanar Computed Tomography Reformations

    SciTech Connect

    Dugas, Alexandre; Therasse, Eric; Kauffmann, Claude; Tang, An; Elkouri, Stephane; Nozza, Anna; Giroux, Marie-France; Oliva, Vincent L.; Soulez, Gilles

    2012-08-15

    Purpose: To compare different methods measuring abdominal aortic aneurysm (AAA) maximal diameter (Dmax) and its progression on multidetector computed tomography (MDCT) scan. Materials and Methods: Forty AAA patients with two MDCT scans acquired at different times (baseline and follow-up) were included. Three observers measured AAA diameters by seven different methods: on axial images (anteroposterior, transverse, maximal, and short-axis views) and on multiplanar reformation (MPR) images (coronal, sagittal, and orthogonal views). Diameter measurement and progression were compared over time for the seven methods. Reproducibility of measurement methods was assessed by intraclass correlation coefficient (ICC) and Bland-Altman analysis. Results: Dmax, as measured on axial slices at baseline and follow-up (FU) MDCTs, was greater than that measured using the orthogonal method (p = 0.046 for baseline and 0.028 for FU), whereas Dmax measured with the orthogonal method was greater those using all other measurement methods (p-value range: <0.0001-0.03) but anteroposterior diameter (p = 0.18 baseline and 0.10 FU). The greatest interobserver ICCs were obtained for the orthogonal and transverse methods (0.972) at baseline and for the orthogonal and sagittal MPR images at FU (0.973 and 0.977). Interobserver ICC of the orthogonal method to document AAA progression was greater (ICC = 0.833) than measurements taken on axial images (ICC = 0.662-0.780) and single-plane MPR images (0.772-0.817). Conclusion: AAA Dmax measured on MDCT axial slices overestimates aneurysm size. Diameter as measured by the orthogonal method is more reproducible, especially to document AAA progression.

  14. Relationship between glycemic control and coronary artery disease severity, prevalence and plaque characteristics by computed tomography coronary angiography in asymptomatic type 2 diabetic patients.

    PubMed

    Tavares, C A F; Rassi, C H R E; Fahel, M G; Wajchenberg, B L; Rochitte, C E; Lerario, A C

    2016-10-01

    Evaluate whether glycemic control in type 2 diabetes (DM2) asymptomatic for coronary artery disease (CAD) affects not only the presence and magnitude of CAD but also the characteristics of plaque vulnerability using multidetector row computed coronary tomography (MDCT). Acute coronary syndrome (ACS) is frequently observed in asymptomatic DM2 patients. Positive vessel remodeling (PR) and low-attenuation plaques (LAP) identified by MDCT have been demonstrated to be characteristics of subsequent culprit lesions of ACS. However, little is known regarding plaque characteristics in asymptomatic diabetic patients and their relationship with glycemic control. Ninety asymptomatic DM2 patients, aged 40-65 years old, underwent MDCT. The presence of atherosclerotic obstruction, defined as coronary stenosis ≥50 %, and plaque characteristics were compared between two groups of patients with A1c < 7 and A1c ≥ 7 %. Of the 90 patients, 38 (42.2 %) presented with coronary atherosclerotic plaques, 11 had A1c < 7 % and 27 had A1c ≥ 7 % (p = 0.0006). Fourteen patients had significant lumen obstruction higher than 50 %: 3 in the A1c < 7 % group and 11 in the A1c ≥ 7 % group (p = 0.02). Non-calcified plaque was more prevalent in the A1c ≥ 7 % group (p = 0.005). In eleven patients, the simultaneous presence of two vulnerability plaque characteristics (PR and LAP) were observed more frequently in the A1c ≥ 7 group (n = 8) than in the A1c < 7 group (n = 3) (p = 0.04). Asymptomatic DM2 patients with A1c ≥ 7 % have a higher frequency of CAD and a higher proportion of vulnerable atherosclerotic coronary plaque by MDCT compared to patients with DM2 with A1c < 7 in our study.

  15. Giant aneurysm of the left main coronary artery with fistulous communication to the right atrium.

    PubMed

    Zhu, Zhicheng; Wang, Yong; Xu, Rihao; Li, Dan; Wang, Tiance; Li, Bo; Zhang, Shudong; Liu, Kexiang

    2015-09-11

    The giant coronary artery aneurysm combined with coronary artery fistula is extremely uncommon. In our case, there was a giant aneurysm of the left main coronary artery with fistulous communication to the right atrium, combined with moderate aortic valve regurgitation, which was initially found by transthoracic echocardiogram and subsequently confirmed by the 256-slice multidetector computer tomography (MDCT) coronary angiography. After consultation, the patient received surgical treatment, including the closure of the drainage and origin sites of the aneurysm and the aortic valve replacement. The patient recovered uneventfully.

  16. [Application possibilities and initial experience with digital volume tomography in hand and wrist imaging].

    PubMed

    Goerke, Sebastian M; Neubauer, J; Zajonc, H; Thiele, J R; Kotter, E; Langer, M; Stark, G B; Lampert, F M

    2015-02-01

    During the last decade, DVT (digital volume tomography) imaging has become a widely used standard technique in head and neck imaging. Lower radiation exposure compared to conventional computed tomography (MDCT) has been described. Recently, DVT has been developed as an extremity scanner and as such represents a new imaging technique for hand surgery. We here describe the first 24 months experience with this new imaging modality in hand and wrist imaging by presenting representative cases and by describing the technical background. Furthermore, the method's advantages and disadvantages are discussed with reference to the given literature.

  17. Cirsoid Aneurysm of Coronary Arteries Associated with Arterioventricular Fistula Evaluated by 64-Multidetector CT Coronary Angiography: Depiction of a Case

    SciTech Connect

    Marrone, Gianluca Mamone, Giuseppe; Milazzo, Mariapina; Caruso, Settimo; Baravoglia, Cesar Hernandez; Vitulo, Patrizio; Gridelli, Bruno; Luca, Angelo

    2009-05-15

    A female patient with severe pulmonary hypertension was admitted for lung transplant evaluation. As an incidental finding, the chest CT showed diffuse and dilated coronaries, not detected at previous echocardiography. A coronary CT angiography was then performed using a 64-multidetector computed tomography (MDCT) scanner to better evaluate the coronary tree. The images obtained after postprocessing demonstrated tremendously aneurysmatic and tortuous coronary arteries and the presence of a septal branch deepening into the myocardium and penetrating the right ventricle cavity, forming an abnormal arterioventricular fistula. A causal relation between the aneurysms and the fistula is suspected.

  18. Emergency cardiac imaging: state of the art.

    PubMed

    Kuo, Dick; Dilsizian, Vasken; Prasad, Rajnish; White, Charles S

    2006-02-01

    Multiple strategies and testing modalities are available to evaluate patients presenting to the emergency department with cardiac complaints. Many provide anatomic and prognostic information about coronary stenosis and long-term out-comes. Although nuclear and stress echo imaging have the ability to predict outcomes in patients in the emergency department population, the newer modalities of cardiac imaging (EBCT, MDCT,and CMR) continue to show promising results and may soon be incorporated into emergency department chest pain centers. Protocols can be developed within an institution to meet the needs of the patient population while minimizing risk and improving outcomes for all patients. PMID:16326256

  19. Genome-wide analysis of murine renal distal convoluted tubular cells for the target genes of mineralocorticoid receptor

    SciTech Connect

    Ueda, Kohei; Fujiki, Katsunori; Shirahige, Katsuhiko; Gomez-Sanchez, Celso E.; Fujita, Toshiro; Nangaku, Masaomi; Nagase, Miki

    2014-02-28

    Highlights: • We define a target gene of MR as that with MR-binding to the adjacent region of DNA. • We use ChIP-seq analysis in combination with microarray. • We, for the first time, explore the genome-wide binding profile of MR. • We reveal 5 genes as the direct target genes of MR in the renal epithelial cell-line. - Abstract: Background and objective: Mineralocorticoid receptor (MR) is a member of nuclear receptor family proteins and contributes to fluid homeostasis in the kidney. Although aldosterone-MR pathway induces several gene expressions in the kidney, it is often unclear whether the gene expressions are accompanied by direct regulations of MR through its binding to the regulatory region of each gene. The purpose of this study is to identify the direct target genes of MR in a murine distal convoluted tubular epithelial cell-line (mDCT). Methods: We analyzed the DNA samples of mDCT cells overexpressing 3xFLAG-hMR after treatment with 10{sup −7} M aldosterone for 1 h by chromatin immunoprecipitation with deep-sequence (ChIP-seq) and mRNA of the cell-line with treatment of 10{sup −7} M aldosterone for 3 h by microarray. Results: 3xFLAG-hMR overexpressed in mDCT cells accumulated in the nucleus in response to 10{sup −9} M aldosterone. Twenty-five genes were indicated as the candidate target genes of MR by ChIP-seq and microarray analyses. Five genes, Sgk1, Fkbp5, Rasl12, Tns1 and Tsc22d3 (Gilz), were validated as the direct target genes of MR by quantitative RT-qPCR and ChIP-qPCR. MR binding regions adjacent to Ctgf and Serpine1 were also validated. Conclusions: We, for the first time, captured the genome-wide distribution of MR in mDCT cells and, furthermore, identified five MR target genes in the cell-line. These results will contribute to further studies on the mechanisms of kidney diseases.

  20. Improving Image Quality of On-Board Cone-Beam CT in Radiation Therapy Using Image Information Provided by Planning Multi-Detector CT: A Phantom Study

    PubMed Central

    Yang, Ching-Ching; Chen, Fong-Lin; Lo, Yeh-Chi

    2016-01-01

    Purpose The aim of this study was to improve the image quality of cone-beam computed tomography (CBCT) mounted on the gantry of a linear accelerator used in radiation therapy based on the image information provided by planning multi-detector CT (MDCT). Methods MDCT-based shading correction for CBCT and virtual monochromatic CT (VMCT) synthesized using the dual-energy method were performed. In VMCT, the high-energy data were obtained from CBCT, while the low-energy data were obtained from MDCT. An electron density phantom was used to investigate the efficacy of shading correction and VMCT on improving the target detectability, Hounsfield unit (HU) accuracy and variation, which were quantified by calculating the contrast-to-noise ratio (CNR), the percent difference (%Diff) and the standard deviation of the CT numbers for tissue equivalent background material, respectively. Treatment plan studies for a chest phantom were conducted to investigate the effects of image quality improvement on dose planning. Results For the electron density phantom, the mean value of CNR was 17.84, 26.78 and 34.31 in CBCT, shading-corrected CBCT and VMCT, respectively. The mean value of %Diff was 152.67%, 11.93% and 7.66% in CBCT, shading-corrected CBCT and VMCT, respectively. The standard deviation within a uniform background of CBCT, shading-corrected CBCT and VMCT was 85, 23 and 15 HU, respectively. With regards to the chest phantom, the monitor unit (MU) difference between the treatment plan calculated using MDCT and those based on CBCT, shading corrected CBCT and VMCT was 6.32%, 1.05% and 0.94%, respectively. Conclusions Enhancement of image quality in on-board CBCT can contribute to daily patient setup and adaptive dose delivery, thus enabling higher confidence in patient treatment accuracy in radiation therapy. Based on our results, VMCT has the highest image quality, followed by the shading corrected CBCT and the original CBCT. The research results presented in this study should be

  1. Inferior Vena Cava Duplication: Incidental Case in a Young Woman.

    PubMed

    Coco, Danilo; Cecchini, Sara; Leanza, Silvana; Viola, Massimo; Ricci, Stefano; Campagnacci, Roberto

    2016-01-01

    A case of a double inferior vena cava (IVC) with retroaortic left renal vein, azygos continuation of the IVC, and presence of the hepatic portion of the IVC drained into the right renal vein is reported and the embryologic, clinical, and radiological significance is discussed. The diagnosis is suggested by multidetector computed tomography (MDCT), which reveals the aberrant vascular structures. Awareness of different congenital anomalies of IVC is necessary for radiologists to avoid diagnostic pitfalls and they should be remembered because they can influence several surgical interventions and endovascular procedures. PMID:27217964

  2. [The role of multidetector computer tomography in diagnosis of acute pancreatitis].

    PubMed

    Lohanikhina, K Iu; Hordiienko, K P; Kozarenko, T M

    2014-10-01

    With the objective to improve the diagnostic semiotics of an acute pancreatitis (AP) 35 patients were examined, using 64-cut computeric tomograph Lightspeed VCT (GE, USA) with intravenous augmentation in arterial and portal phases. Basing on analysis of the investigations conducted, using multidetector computeric tomography (MDCT), the AP semiotics was systematized, which is characteristic for oedematous and destructive forms, diagnosed in 19 (44.2%) and 16 (45.8%) patients, accordingly. The procedure for estimation of preservation of the organ functional capacity in pancreonecrosis pres- ence was elaborated, promoting rising of the method diagnostic efficacy by 5.3 - 9.4%. PMID:25675779

  3. Correlations between forced oscillation technique parameters and pulmonary densitovolumetry values in patients with acromegaly

    PubMed Central

    Camilo, G.B.; Carvalho, A.R.S.; Machado, D.C.; Mogami, R.; Kasuki, L.; Gadelha, M.R.; Melo, P.L.; Lopes, A.J.

    2015-01-01

    The aims of this study were to evaluate the forced oscillation technique (FOT) and pulmonary densitovolumetry in acromegalic patients and to examine the correlations between these findings. In this cross-sectional study, 29 non-smoking acromegalic patients and 17 paired controls were subjected to the FOT and quantification of lung volume using multidetector computed tomography (Q-MDCT). Compared with the controls, the acromegalic patients had a higher value for resonance frequency [15.3 (10.9-19.7) vs 11.4 (9.05-17.6) Hz, P=0.023] and a lower value for mean reactance [0.32 (0.21-0.64) vs 0.49 (0.34-0.96) cm H2O/L/s2, P=0.005]. In inspiratory Q-MDCT, the acromegalic patients had higher percentages of total lung volume (TLV) for nonaerated and poorly aerated areas [0.42% (0.30-0.51%) vs 0.25% (0.20-0.32%), P=0.039 and 3.25% (2.48-3.46%) vs 1.70% (1.45-2.15%), P=0.001, respectively]. Furthermore, the acromegalic patients had higher values for total lung mass in both inspiratory and expiratory Q-MDCT [821 (635-923) vs 696 (599-769) g, P=0.021 and 844 (650-945) vs 637 (536-736) g, P=0.009, respectively]. In inspiratory Q-MDCT, TLV showed significant correlations with all FOT parameters. The TLV of hyperaerated areas showed significant correlations with intercept resistance (rs=−0.602, P<0.001) and mean resistance (rs=−0.580, P<0.001). These data showed that acromegalic patients have increased amounts of lung tissue as well as nonaerated and poorly aerated areas. Functionally, there was a loss of homogeneity of the respiratory system. Moreover, there were correlations between the structural and functional findings of the respiratory system, consistent with the pathophysiology of the disease. PMID:26445330

  4. Comparison of accuracy of aortic root annulus assessment with cardiac magnetic resonance versus echocardiography and multidetector computed tomography in patients referred for transcatheter aortic valve implantation.

    PubMed

    Pontone, Gianluca; Andreini, Daniele; Bartorelli, Antonio L; Bertella, Erika; Mushtaq, Saima; Gripari, Paola; Loguercio, Monica; Cortinovis, Sarah; Baggiano, Andrea; Conte, Edoardo; Beltrama, Virginia; Annoni, Andrea; Formenti, Alberto; Tamborini, Gloria; Muratori, Manuela; Guaricci, Andrea; Alamanni, Francesco; Ballerini, Giovanni; Pepi, Mauro

    2013-12-01

    The evaluation of the aortic root in patients referred for transcatheter aortic valve implantation is crucial. The aim of the present study was to compare the accuracy of cardiac magnetic resonance (CMR) evaluation of the aortic annulus (AoA) with transthoracic and transesophageal echocardiography and multidetector computed tomography (MDCT) in patients referred for transcatheter aortic valve implantation. In 50 patients, maximum diameter, minimum diameter and AoA, length of the left coronary, right coronary, and noncoronary aortic leaflets, degree (grades 1 to 4) of aortic leaflet calcification, and distance between AoA and coronary artery ostia were assessed. AoA maximum diameter, minimum diameter, and area by CMR were 26.4 ± 2.8 mm, 20.6 ± 2.3 mm, 449.8 ± 86.2 mm(2), respectively. The length of left coronary, right coronary, and noncoronary leaflets by CMR were 13.9 ± 2.2, 13.3 ± 2.1, and 13.4 ± 1.8 mm, respectively, whereas the score of aortic leaflet calcifications was 2.9 ± 0.8. Finally, the distances between AoA and left main and right coronary artery ostia were 16.1 ± 2.8 and 16.1 ± 4.4 mm, respectively. Regarding AoA area, transthoracic and transesophageal echocardiography showed an underestimation (p <0.01), with a moderate agreement (r: 0.5 and 0.6, respectively, p <0.01) compared with CMR. No differences and excellent correlation were observed between CMR and MDCT for all parameters (r: 0.9, p <0.01), except for aortic leaflet calcifications that were underestimated by CMR. In conclusion, aortic root assessment with CMR including AoA size, aortic leaflet length, and coronary artery ostia height is accurate compared with MDCT. CMR may be a valid imaging alternative in patients unsuitable for MDCT. PMID:24045059

  5. Magnetic resonance imaging and multi-detector computed tomography assessment of extracellular compartment in ischemic and non-ischemic myocardial pathologies.

    PubMed

    Saeed, Maythem; Hetts, Steven W; Jablonowski, Robert; Wilson, Mark W

    2014-11-26

    Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume (ECV) in myocardium is critical to initiate effective treatment. The three compartments in healthy myocardium are: intravascular (approximately 10% of tissue volume), interstitium (approximately 15%) and intracellular (approximately 75%). Myocardial cells, fibroblasts and vascular endothelial/smooth muscle cells represent intracellular compartment and the main proteins in the interstitium are types I/III collagens. Microscopic studies have shown that expansion of ECV is an important feature of diffuse physiologic fibrosis (e.g., aging and obesity) and pathologic fibrosis [heart failure, aortic valve disease, hypertrophic cardiomyopathy, myocarditis, dilated cardiomyopathy, amyloidosis, congenital heart disease, aortic stenosis, restrictive cardiomyopathy (hypereosinophilic and idiopathic types), arrythmogenic right ventricular dysplasia and hypertension]. This review addresses recent advances in measuring of ECV in ischemic and non-ischemic myocardial pathologies. Magnetic resonance imaging (MRI) has the ability to characterize tissue proton relaxation times (T1, T2, and T2*). Proton relaxation times reflect the physical and chemical environments of water protons in myocardium. Delayed contrast enhanced-MRI (DE-MRI) and multi-detector computed tomography (DE-MDCT) demonstrated hyper-enhanced infarct, hypo-enhanced microvascular obstruction zone and moderately enhanced peri-infarct zone, but are limited for visualizing diffuse fibrosis and patchy microinfarct despite the increase in ECV. ECV can be measured on equilibrium contrast enhanced MRI/MDCT and MRI longitudinal relaxation time mapping. Equilibrium contrast enhanced MRI/MDCT and MRI T1 mapping is currently used, but at a lower scale, as an alternative to invasive sub-endomyocardial biopsies to eliminate the need for anesthesia, coronary

  6. Functional Imaging: CT and MRI

    PubMed Central

    van Beek, Edwin JR; Hoffman, Eric A

    2008-01-01

    Synopsis Numerous imaging techniques permit evaluation of regional pulmonary function. Contrast-enhanced CT methods now allow assessment of vasculature and lung perfusion. Techniques using spirometric controlled MDCT allow for quantification of presence and distribution of parenchymal and airway pathology, Xenon gas can be employed to assess regional ventilation of the lungs and rapid bolus injections of iodinated contrast agent can provide quantitative measure of regional parenchymal perfusion. Advances in magnetic resonance imaging (MRI) of the lung include gadolinium-enhanced perfusion imaging and hyperpolarized helium imaging, which can allow imaging of pulmonary ventilation and .measurement of the size of emphysematous spaces. PMID:18267192

  7. Correlative imaging in gallbladder carcinoma.

    PubMed

    Willekens, I; Goethals, L R; Brussaard, C; Verdries, D; de Mey, J

    2014-01-01

    Gallbladder carcinoma is a relatively rare malignant epithelial neoplasm, arising from gallbladder mucosa. It is the fifth most common gastrointestinal malignancy and the most common biliary tract cancer. Early diagnosis remains difficult, because clinical symptoms are sparse and non-specific, often resulting in advanced stage disease at the time of diagnosis. The most common feature of gallbladder carcinoma on different imaging modalities is focal wall thickening, associated with a large eccentric tumor mass. In this case we report the imaging characteristics of gallbladder carcinoma on ultrasound, MDCT and 18F-FDG PET/CT.

  8. Organ dose measurements from multiple-detector computed tomography using a commercial dosimetry system and tomographic, physical phantoms

    NASA Astrophysics Data System (ADS)

    Lavoie, Lindsey K.

    The technology of computed tomography (CT) imaging has soared over the last decade with the use of multi-detector CT (MDCT) scanners that are capable of performing studies in a matter of seconds. While the diagnostic information obtained from MDCT imaging is extremely valuable, it is important to ensure that the radiation doses resulting from these studies are at acceptably safe levels. This research project focused on the measurement of organ doses resulting from modern MDCT scanners. A commercially-available dosimetry system was used to measure organ doses. Small dosimeters made of optically-stimulated luminescent (OSL) material were analyzed with a portable OSL reader. Detailed verification of this system was performed. Characteristics studied include energy, scatter, and angular responses; dose linearity, ability to erase the exposed dose and ability to reuse dosimeters multiple times. The results of this verification process were positive. While small correction factors needed to be applied to the dose reported by the OSL reader, these factors were small and expected. Physical, tomographic pediatric and adult phantoms were used to measure organ doses. These phantoms were developed from CT images and are composed of tissue-equivalent materials. Because the adult phantom is comprised of numerous segments, dosimeters were placed in the phantom at several organ locations, and doses to select organs were measured using three clinical protocols: pediatric craniosynostosis, adult brain perfusion and adult cardiac CT angiography (CTA). A wide-beam, 320-slice, volumetric CT scanner and a 64-slice, MDCT scanner were used for organ dose measurements. Doses ranged from 1 to 26 mGy for the pediatric protocol, 1 to 1241 mGy for the brain perfusion protocol, and 2-100 mGy for the cardiac protocol. In most cases, the doses measured on the 64-slice scanner were higher than those on the 320-slice scanner. A methodology to measure organ doses with OSL dosimeters received from CT

  9. Multidetector CT findings of complications of surgical and endovascular treatment of aortic aneurysms.

    PubMed

    Valente, Tullio; Rossi, Giovanni; Rea, Gaetano; Pinto, Antonio; Romano, Luigia; Davies, Joseph; Scaglione, Mariano

    2014-09-01

    Aortic aneurysms remain a significant problem in the population, and there is a concerted effort to identify, define, image, and treat these conditions to ultimately improve outcomes. The rapid development of diagnostic modalities, operative strategies, and endovascular techniques within the realm of this aortic disease has transformed the field and broadened the spectrum of patients that can be treated with minimally invasive techniques. This investigation has a broad spectrum of normal expected findings that must be differentiated from early or late complications in which intervention is required. In this article, normal and abnormal postoperative and post-TEVAR/EVAR MDCT findings are described. PMID:25173654

  10. Correlations between forced oscillation technique parameters and pulmonary densitovolumetry values in patients with acromegaly.

    PubMed

    Camilo, G B; Carvalho, A R S; Machado, D C; Mogami, R; Kasuki, L; Gadelha, M R; Melo, P L; Lopes, A J

    2015-10-01

    The aims of this study were to evaluate the forced oscillation technique (FOT) and pulmonary densitovolumetry in acromegalic patients and to examine the correlations between these findings. In this cross-sectional study, 29 non-smoking acromegalic patients and 17 paired controls were subjected to the FOT and quantification of lung volume using multidetector computed tomography (Q-MDCT). Compared with the controls, the acromegalic patients had a higher value for resonance frequency [15.3 (10.9-19.7) vs 11.4 (9.05-17.6) Hz, P=0.023] and a lower value for mean reactance [0.32 (0.21-0.64) vs 0.49 (0.34-0.96) cm H2O/L/s2, P=0.005]. In inspiratory Q-MDCT, the acromegalic patients had higher percentages of total lung volume (TLV) for nonaerated and poorly aerated areas [0.42% (0.30-0.51%) vs 0.25% (0.20-0.32%), P=0.039 and 3.25% (2.48-3.46%) vs 1.70% (1.45-2.15%), P=0.001, respectively]. Furthermore, the acromegalic patients had higher values for total lung mass in both inspiratory and expiratory Q-MDCT [821 (635-923) vs 696 (599-769) g, P=0.021 and 844 (650-945) vs 637 (536-736) g, P=0.009, respectively]. In inspiratory Q-MDCT, TLV showed significant correlations with all FOT parameters. The TLV of hyperaerated areas showed significant correlations with intercept resistance (rs=-0.602, P<0.001) and mean resistance (rs=-0.580, P<0.001). These data showed that acromegalic patients have increased amounts of lung tissue as well as nonaerated and poorly aerated areas. Functionally, there was a loss of homogeneity of the respiratory system. Moreover, there were correlations between the structural and functional findings of the respiratory system, consistent with the pathophysiology of the disease. PMID:26445330

  11. [The role of multidetector computer tomography in diagnosis of acute pancreatitis].

    PubMed

    Lohanikhina, K Iu; Hordiienko, K P; Kozarenko, T M

    2014-10-01

    With the objective to improve the diagnostic semiotics of an acute pancreatitis (AP) 35 patients were examined, using 64-cut computeric tomograph Lightspeed VCT (GE, USA) with intravenous augmentation in arterial and portal phases. Basing on analysis of the investigations conducted, using multidetector computeric tomography (MDCT), the AP semiotics was systematized, which is characteristic for oedematous and destructive forms, diagnosed in 19 (44.2%) and 16 (45.8%) patients, accordingly. The procedure for estimation of preservation of the organ functional capacity in pancreonecrosis pres- ence was elaborated, promoting rising of the method diagnostic efficacy by 5.3 - 9.4%.

  12. Tuberculosis of the genitourinary system-Urinary tract tuberculosis: Renal tuberculosis-Part II

    PubMed Central

    Merchant, Suleman; Bharati, Alpa; Merchant, Neesha

    2013-01-01

    This article reviews the computed tomography and magnetic resonance imaging (MRI) features of renal tuberculosis (TB), including TB in transplant recipients and immunocompromised patients. Multi detector computed tomography (MDCT) forms the mainstay of cross-sectional imaging in renal TB. It can easily identify calcification, renal scars, mass lesions, and urothelial thickening. The combination of uneven caliectasis, with urothelial thickening and lack of pelvic dilatation, can also be demonstrated on MDCT. MRI is a sensitive modality for demonstration of features of renal TB, including tissue edema, asymmetric perinephric fat stranding, and thickening of Gerota's fascia, all of which may be clues to focal pyelonephritis of tuberculous origin. Diffusion-weighted MR imaging with apparent diffusion coefficient (ADC) values may help in differentiating hydronephrosis from pyonephrosis. ADC values also have the potential to serve as a sensitive non-invasive biomarker of renal fibrosis. Immunocompromised patients are at increased risk of renal TB. In transplant patients, renal TB, including tuberculous interstitial nephritis, is an important cause of graft dysfunction. Renal TB in patients with HIV more often shows greater parenchymal affection, with poorly formed granulomas and relatively less frequent findings of caseation and stenosis. Atypical mycobacterial infections are also more common in immunocompromised patients. PMID:23986619

  13. Imaging techniques in cardiac resynchronization therapy

    PubMed Central

    Sá, Maria Isabel; de Roos, Albert; Westenberg, Jos J. M.

    2007-01-01

    Cardiac resynchronization therapy is a high cost therapeutic option with proven efficacy on improving symptoms of ventricular failure and for reducing both hospitalization and mortality. However, a significant number of patients do not respond to cardiac resynchronization therapy that is due to various reasons. Identification of the optimal pacing site is crucial to obtain the best therapeutic result that necessitates careful patient selection. Currently, using echocardiography for mechanical dyssynchrony assessment performs patient selection. Multi-Detector-Row Computed Tomography (MDCT) and Magnetic Resonance Imaging (MRI) are new imaging techniques that may assist the cardiologist in patient selection. These new imaging techniques have the potential to improve the success rate of cardiac resynchronization therapy, due to pre-interventional evaluation of the venous coronary anatomy, to evaluation of the presence of scar tissue, and to improved evaluation of mechanical dyssynchrony. In conclusion, clinical issues associated with heart failure in potential candidates for cardiac resynchronization therapy, and the information regarding this therapy that can be provided by the imaging techniques echocardiography, MDCT, and MRI, are reviewed. PMID:17503216

  14. Detection and classification of interstitial lung diseases and emphysema using a joint morphological-fuzzy approach

    NASA Astrophysics Data System (ADS)

    Chang Chien, Kuang-Che; Fetita, Catalin; Brillet, Pierre-Yves; Prêteux, Françoise; Chang, Ruey-Feng

    2009-02-01

    Multi-detector computed tomography (MDCT) has high accuracy and specificity on volumetrically capturing serial images of the lung. It increases the capability of computerized classification for lung tissue in medical research. This paper proposes a three-dimensional (3D) automated approach based on mathematical morphology and fuzzy logic for quantifying and classifying interstitial lung diseases (ILDs) and emphysema. The proposed methodology is composed of several stages: (1) an image multi-resolution decomposition scheme based on a 3D morphological filter is used to detect and analyze the different density patterns of the lung texture. Then, (2) for each pattern in the multi-resolution decomposition, six features are computed, for which fuzzy membership functions define a probability of association with a pathology class. Finally, (3) for each pathology class, the probabilities are combined up according to the weight assigned to each membership function and two threshold values are used to decide the final class of the pattern. The proposed approach was tested on 10 MDCT cases and the classification accuracy was: emphysema: 95%, fibrosis/honeycombing: 84% and ground glass: 97%.

  15. Assessing vertebral fracture risk on volumetric quantitative computed tomography by geometric characterization of trabecular bone structure

    NASA Astrophysics Data System (ADS)

    Checefsky, Walter A.; Abidin, Anas Z.; Nagarajan, Mahesh B.; Bauer, Jan S.; Baum, Thomas; Wismüller, Axel

    2016-03-01

    The current clinical standard for measuring Bone Mineral Density (BMD) is dual X-ray absorptiometry, however more recently BMD derived from volumetric quantitative computed tomography has been shown to demonstrate a high association with spinal fracture susceptibility. In this study, we propose a method of fracture risk assessment using structural properties of trabecular bone in spinal vertebrae. Experimental data was acquired via axial multi-detector CT (MDCT) from 12 spinal vertebrae specimens using a whole-body 256-row CT scanner with a dedicated calibration phantom. Common image processing methods were used to annotate the trabecular compartment in the vertebral slices creating a circular region of interest (ROI) that excluded cortical bone for each slice. The pixels inside the ROI were converted to values indicative of BMD. High dimensional geometrical features were derived using the scaling index method (SIM) at different radii and scaling factors (SF). The mean BMD values within the ROI were then extracted and used in conjunction with a support vector machine to predict the failure load of the specimens. Prediction performance was measured using the root-mean-square error (RMSE) metric and determined that SIM combined with mean BMD features (RMSE = 0.82 +/- 0.37) outperformed MDCT-measured mean BMD (RMSE = 1.11 +/- 0.33) (p < 10-4). These results demonstrate that biomechanical strength prediction in vertebrae can be significantly improved through the use of SIM-derived texture features from trabecular bone.

  16. Radiological protection in computed tomography and cone beam computed tomography.

    PubMed

    Rehani, M M

    2015-06-01

    The International Commission on Radiological Protection (ICRP) has sustained interest in radiological protection in computed tomography (CT), and ICRP Publications 87 and 102 focused on the management of patient doses in CT and multi-detector CT (MDCT) respectively. ICRP forecasted and 'sounded the alarm' on increasing patient doses in CT, and recommended actions for manufacturers and users. One of the approaches was that safety is best achieved when it is built into the machine, rather than left as a matter of choice for users. In view of upcoming challenges posed by newer systems that use cone beam geometry for CT (CBCT), and their widened usage, often by untrained users, a new ICRP task group has been working on radiological protection issues in CBCT. Some of the issues identified by the task group are: lack of standardisation of dosimetry in CBCT; the false belief within the medical and dental community that CBCT is a 'light', low-dose CT whereas mobile CBCT units and newer applications, particularly C-arm CT in interventional procedures, involve higher doses; lack of training in radiological protection among clinical users; and lack of dose information and tracking in many applications. This paper provides a summary of approaches used in CT and MDCT, and preliminary information regarding work just published for radiological protection in CBCT.

  17. Abdominal crush injury in the Sichuan earthquake evaluated by multidetector computed tomography

    PubMed Central

    Chen, Tian-Wu; Yang, Zhi-Gang; Dong, Zhi-Hui; Shao, Heng; Chu, Zhi-Gang; Tang, Si-Shi

    2011-01-01

    AIM: To investigate the features of abdominal crush injuries resulting from an earthquake using multidetector computed tomography (MDCT). METHODS: Fifty-one survivors with abdominal crush injuries due to the 2008 Sichuan earthquake underwent emergency non-enhanced scans with 16-row MDCT. Data were reviewed focusing on anatomic regions including lumbar vertebrae, abdominal wall soft tissue, retroperitoneum and intraperitoneal space; and types of traumatic lesions. RESULTS: Fractures of lumbar vertebrae and abdominal wall soft tissue injuries were more common than retro- and intraperitoneal injuries (P < 0.05). With regard to the 49 lumbar vertebral fractures in 24 patients, these occurred predominantly in the transverse process (P < 0.05), and 66.67% of patients (16/24) had fractures of multiple vertebrae, predominantly two vertebrae in 62.5% of patients (10/16), mainly in L1-3 vertebrae in 81.63% of the vertebrae (40/49). Retroperitoneal injuries occurred more frequently than intraperitoneal injuries (P < 0.05), and renal and liver injuries were most often seen in the retroperitoneum and in the intraperitoneal space, respectively (all P < 0.05). CONCLUSION: Transverse process fractures in two vertebrae among L1-3 vertebrae, injury of abdominal wall soft tissue, and renal injury might be features of earthquake-related crush abdominal injury. PMID:21666819

  18. Frequent Ischemic Stroke as First Manifestation of Occult Colon Cancer: A Rare Case

    PubMed Central

    Tsai, Chia-Chan; Wu, Meng-Ni

    2015-01-01

    Patient: Male, 46 Final Diagnosis: Adenocarcinoma of the ascending colon Symptoms: Anemia • diplopia • hemiparesis • slurred speech Medication: — Clinical Procedure: Multi-detector computed tomography • colonoscopy Specialty: Neurology Objective: Rare co-existance of disease or pathology Background: It is rare that occult cancer presents with frequent ischemic stroke as the sole manifestation. Case Report: We report the case of a 46-year-old man with frequent stroke in different vascular areas, with diabetes and hypercholesterolemia identified as risk factors. The results of biochemistry, young stroke profiles, trans-cranial and extra-cranial carotid Doppler, and 24-h Holter electrocardiogram were within normal limits. The reports of transthoracic echocardiography (TTE) were unremarkable. Finally, a multi-detector computed tomography (MDCT) demonstrated a thrombus in the posterior-lateral aspect of the left atrium and non-bacterial thrombotic endocarditis (NBTE) was suspected. The results motivated the survey for occult cancer, and adenocarcinoma of the ascending colon was confirmed on colonoscopy pathology. Conclusions: We suggest that evaluating the possibility of occult cancer should be emphasized in patients of frequent stroke refractory to therapy, whether risk factors are already identified or not. Furthermore, we assume MDCT can be an alternative way to detect cardiogenic embolic sources in stroke patients. PMID:26460069

  19. Cone beam CT for dental and maxillofacial imaging: dose matters.

    PubMed

    Pauwels, Ruben

    2015-07-01

    The widespread use of cone-beam CT (CBCT) in dentistry has led to increasing concern regarding justification and optimisation of CBCT exposures. When used as a substitute to multidetector CT (MDCT), CBCT can lead to significant dose reduction; however, low-dose protocols of current-generation MDCTs show that there is an overlap between CBCT and MDCT doses. More importantly, although the 3D information provided by CBCT can often lead to improved diagnosis and treatment compared with 2D radiographs, a routine or excessive use of CBCT would lead to a substantial increase of the collective patient dose. The potential use of CBCT for paediatric patients (e.g. developmental disorders, trauma and orthodontic treatment planning) further increases concern regarding its proper application. This paper provides an overview of justification and optimisation issues in dental and maxillofacial CBCT. The radiation dose in CBCT will be briefly reviewed. The European Commission's Evidence Based Guidelines prepared by the SEDENTEXCT Project Consortium will be summarised, and (in)appropriate use of CBCT will be illustrated for various dental applications. PMID:25805884

  20. MRI of the lung: state of the art.

    PubMed

    Wielpütz, Mark; Kauczor, Hans-Ulrich

    2012-01-01

    Magnetic resonance imaging (MRI) of the lung is technically challenging due to the low proton density and fast signal decay of the lung parenchyma itself. Additional challenges consist of tissue loss, hyperinflation, and hypoxic hypoperfusion, e.g., in emphysema, a so-called "minus-pathology". However, pathological changes resulting in an increase of tissue ("plus-pathology"), such as atelectases, nodules, infiltrates, mucus, or pleural effusion, are easily depicted with high diagnostic accuracy. Although MRI is inferior or at best equal to multi-detector computed tomography (MDCT) for the detection of subtle morphological features, MRI now offers an increasing spectrum of functional imaging techniques such as perfusion assessment and measurement of ventilation and respiratory mechanics that are superior to what is possible with MDCT. Without putting patients at risk with ionizing radiation, repeated examinations allow for the evaluation of the course of lung disease and monitoring of the therapeutic response through quantitative imaging, providing a level of functional detail that cannot be obtained by any other single imaging modality. As such, MRI will likely be used for clinical applications beyond morphological imaging for many lung diseases. In this article, we review the technical aspects and protocol suggestions for chest MRI and discuss the role of MRI in the evaluation of nodules and masses, airway disease, respiratory mechanics, ventilation, perfusion and hemodynamics, and pulmonary vasculature. PMID:22434450

  1. Computerized left ventricular regional ejection fraction analysis for detection of ischemic coronary artery disease with multidetector CT angiography.

    PubMed

    Zeb, Irfan; Li, Dong; Nasir, Khurram; Gupta, Mohit; Kadakia, Jigar; Gao, Yanlin; Ma, Eva; Mao, Song Shou; Budoff, Matthew

    2013-03-01

    Regional ejection fraction (REF) provides important functional information of the left ventricular regional myocardium. We aimed to test the diagnostic accuracy of computerized REF analysis for detecting the ischemia and significant stenosis with multidetector CT angiography (MDCT). This is a retrospective study including 155 patients who underwent MDCT scans for evaluation of coronary artery disease. Among them, 83 patients also underwent SPECT imaging and invasive coronary angiography (ICA). Two groups of patients were defined: Control group with 0 coronary artery calcium and normal global and regional ventricular function, and comparison group. REF measurement was performed on all patients using computerized software. Control group REF measurements will be used as reference standard (mean-2SD REF/mean global ejection fraction) to define abnormal REF. The sensitivity, specificity, positive and negative predictive value of REF in detecting perfusion defects (fixed and reversible) was 73, 80, 75 and 79 % respectively, in a patient based analysis of comparison group. The diagnostic accuracy of REF in predicting significant stenosis (>50 %) on ICA compared with SPECT was 72 versus 61 % and 85 versus 79 % in patient and vessel based analysis of comparison group, respectively. ROC curve analysis showed REF to be a better predictor of perfusion defects on SPECT compared with significant stenosis (>50 %) alone or stenosis combined with REF (P < 0.05). The computerized assessment of REF analysis is comparable to SPECT in predicting ischemia and a better predictor of significant stenosis than SPECT. This study also provides reference standard to define abnormal values.

  2. Sensitivity and specificity of 3-D texture analysis of lung parenchyma is better than 2-D for discrimination of lung pathology in stage 0 COPD

    NASA Astrophysics Data System (ADS)

    Xu, Ye; Sonka, Milan; McLennan, Geoffrey; Guo, Junfeng; Hoffman, Eric

    2005-04-01

    Lung parenchyma evaluation via multidetector-row CT (MDCT), has significantly altered clinical practice in the early detection of lung disease. Our goal is to enhance our texture-based tissue classification ability to differentiate early pathologic processes by extending our 2-D Adaptive Multiple Feature Method (AMFM) to 3-D AMFM. We performed MDCT on 34 human volunteers in five categories: emphysema in severe Chronic Obstructive Pulmonary Disease (COPD) as EC, emphysema in mild COPD (MC), normal appearing lung in COPD (NC), non-smokers with normal lung function (NN), smokers with normal function (NS). We volumetrically excluded the airway and vessel regions, calculated 24 volumetric texture features for each Volume of Interest (VOI); and used Bayesian rules for discrimination. Leave-one-out and half-half methods were used for testing. Sensitivity, specificity and accuracy were calculated. The accuracy of the leave-one-out method for the four-class classification in the form of 3-D/2-D is: EC: 84.9%/70.7%, MC: 89.8%/82.7%; NC: 87.5.0%/49.6%; NN: 100.0%/60.0%. The accuracy of the leave-one-out method for the two-class classification in the form of 3-D/2-D is: NN: 99.3%/71.6%; NS: 99.7%/74.5%. We conclude that 3-D AMFM analysis of the lung parenchyma improves discrimination compared to 2-D analysis of the same images.

  3. A Three-Dimensional Reconstructive Study of Pelvic Cavity in the New Zealand Rabbit (Oryctolagus cuniculus)

    PubMed Central

    Eken, Emrullah; Kalaycı, İbrahim

    2014-01-01

    The present study has been performed to reveal biometrical aspects and diameter-related differences in terms of sexes regarding pelvic cavity via three-dimensional (3D) reconstruction by using multidetector computed tomography (MDCT) images of pelvic cavity of the New Zealand rabbit. A total of 16 adult New Zealand rabbits, including 8 males and 8 females, were used in this study. Under anesthesia, the images obtained from MDCT were stacked and overlaid to reconstruct the 3D model of the pelvic cavity using 3D modeling software (Mimics 13.1). Measurements, such as the conjugate, transverse, and vertical diameters of the pelvic cavity, and the pelvic inclination were calculated and analyzed statistically. Biometrical differences of the pelvic diameters in New Zealand rabbits of both sexes were shown clearly. It was concluded that the pelvic diameters revealed by 3D modeling techniques can shed light on medical students who take both anatomy training and gynecological applications. The authors hope that the synchronization of medical approaches may give rise to novel diagnostic and therapeutic developments related to pelvic cavity. PMID:25379534

  4. Percutaneous Treatment of Sac Rupture in Abdominal Aortic Aneurysms Previously Excluded with Endovascular Repair (EVAR)

    SciTech Connect

    Lagana, Domenico Mangini, Monica Fontana, Federico; Nicotera, Paolo; Carrafiello, Gianpaolo; Fugazzola, Carlo

    2009-01-15

    The purpose of this study was to assess the feasibility and effectiveness of percutaneous endovascular repair of ruptured abdominal aortic aneurysms (AAAs) previously treated by EVAR. In the last year, two male patients with AAAs, treated 8 and 23 months ago with bifurcated stent-graft, were observed because of lumbar pain and hemorragic shock. Multidetector computed tomography (MDCT) showed a retroperitoneal hematoma; in both cases a type III endoleak was detected, in one case associated with a type II endoleak from the iliolumbar artery. The procedures were performed in the theater, in emergency. Type II endoleak was treated with transcatheter superselective glue injection; type III endoleaks were excluded by a stent-graft extension. The procedures were successful in both patients, with immediate hemodynamic stabilization. MDCT after the procedure showed complete exclusion of the aneurysms. In conclusion, endovascular treatment is a safe and feasible option for the treatment of ruptured AAAs previously treated by EVAR; this approach allows avoidance of surgical conversion, which is technical very challenging, with a high morbidity and mortality rate.

  5. [Multidetector computed tomography in acute abdomen].

    PubMed

    Carreras Aja, M; Arrieta Artieda, I; Borruel Nacenta, S

    2011-10-01

    MDCT has become a fundamental tool for determining the causes of acute abdomen. CT is considered the imaging technique of choice in the diagnostic workup of both localized and diffuse acute abdomen, except in patients in whom acute cholecystitis or acute gynecological disease is suspected and in children, adolescents, and pregnant patients, in whom ultrasonography is the imaging technique of choice. Plain-film X-ray examination has been relegated to the initial management of renal colic, suspected foreign bodies, and intestinal obstruction. One of the drawbacks of MDCT is its use of ionizing radiation, which makes it necessary to filter and direct the examinations as well as to ensure that the most appropriate protocols are used. For this reason, low dose protocols have been developed so that diagnostic studies can be performed with doses of radiation between 2 and 3 mSv; these are normally used in the diagnosis of renal colic and can also be used in selected patients with suspected appendicitis and acute diverticulitis. PMID:21742357

  6. Ductal branch-oriented pancreatic resection for an intraductal papillary mucinous neoplasm in the uncinate process that caused recurrent acute pancreatitis: a case report of successful treatment.

    PubMed

    Natsume, Toshiyuki; Maruyama, Takashi; Kobayashi, Akitoshi; Shimizu, Shinichiro; Tanaka, Hajime; Matsuzaki, Hiroshi; Miyazaki, Akinari; Ohta, Takumi; Sato, Yayoi; Yamamoto, Yuji; Aikawa, Mizuho; Otsuka, Ryota; Yanagihara, Akitoshi

    2013-12-01

    Acute pancreatitis reportedly occurs in about 15 % of cases of branch duct (BD)-intraductal papillary mucinous neoplasms (IPMNs), with two-thirds of BD-IPMNs being located in the head or uncinate process of the pancreas. However, the surgical indications and optimal treatment methods for BD-IPMNs have not been established. A 59-year-old Japanese male with epigastralgia was admitted to our hospital. A multidetector row computed tomography (MDCT) scan disclosed grade I acute pancreatitis. Magnetic resonance cholangiopancreatography disclosed a 1.5-cm BD-IPMN in the uncinate process. Two months after discharge, the epigastralgia recurred, and MDCT again revealed grade I pancreatitis. Due to the repeated episodes of pancreatitis, we performed ductal branch-oriented pancreatic resection. To detect the inferior branch of the Wirsung duct and avoid the development of a pancreatic fistula, we injected indigo carmine into the tumor which confirmed ligation of the inferior branch. Histopathologically, the tumor proved to be an adenoma. The postoperative course was uneventful in both the short- and long-term follow-up and, to date, there has been no recurrence of pancreatitis, or diabetes mellitus during the 6 years since pancreatectomy. This procedure is one of the methods that can be used for the successful resection of a BD-IPMN in the uncinate process that caused recurrent acute pancreatitis.

  7. To assess vascular calcification in the patients of hypoparathyroidism using multidetector computed tomography scan

    PubMed Central

    Agarwal, Pooja; Prakash, Mahesh; Singhal, Manphool; Bhadada, Sanjay Kumar; Gupta, Yashdeep; Khandelwal, Niranjan

    2015-01-01

    Background: Our pilot data showed an increased intima media thickness in the patients with sporadic idiopathic hypoparathyroidism (SIH). Alteration in homeostasis of calcium, phosphate, and parathyroid hormone (PTH) may predispose to increase the risk of cardiovascular morbidity and mortality. The data on objective assessment of this increased risk is however lacking. Objective: To assess the effect of altered calcium, phosphate, and PTH homeostasis in the patients with SIH on coronary calcium score (a marker of increase vascular risk) by multidetector computed tomography scan (MDCT). Methods: In this case-control study, we measured coronary CT calcium score in 30 patients of SIH and compared with 40 age and sex matched healthy subjects. Correlation of coronary calcium score with biochemical parameters was evaluated. Results: Three of the 30 cases (10%) with SIH were found to have coronary artery calcification (CAC) of varying degree, whereas none of the control showed CAC (P = 0.07). The patients with CAC had significantly lower serum calcium levels (albumin corrected), as compared to the patients without CAC. Inverse correlation of CAC was found with serum calcium levels. No correlation was found with other biochemical parameters. Conclusion: The vascular risk is increased in the patients with SIH as assessed by coronary calcium score measured by MDCT. Low serum calcium levels might be a predisposing factor for this increased risk. PMID:26693429

  8. Urethroscrotal Fistula: A Rare Cause of Scrotal Swelling

    PubMed Central

    Parlak, Selcuk; Okay, Aysun E.

    2016-01-01

    Summary Background Urethroscrotal fistula (USF) is an abnormal communication between the urethra and the scrotum. This rare abnormality may be iatrogenic or secondary to perforation of the urethra by a stone. After the passage of urine to the scrotum through the fistula, painless scrotal swelling develops, which disappears completely with manual compression, and voiding can be maintained in this way. Retrograde urethrography (RU) and voiding cystourethrography (VCU) are traditional diagnostic methods, but they have limitations, such as technical difficulties and inability to evaluate the surrounding tissues. Multidetector CT (MDCT), together with reformatted images, can provide valuable information about the surrounding tissues and associated pathologies. Case Report We present a case of a 36-year-old male patient who had painless scrotal swelling after cystolithotomy and urethral stone surgery. The patient indicated that the swelling disappeared after manual compression. A fistula between the bulbous urethra and the scrotum was discovered by MDCT. In our case, we believe that the fistula developed iatrogenically during stone excision or secondary to perforation of the urethra by a stone. Conclusions As a rare pathology, urethroscrotal fistula should be considered in men with a history of urethral stone surgery and symptoms, including painless scrotal swelling, which can be manually compressed after voiding.

  9. Double congenital fistulae with aneurysm diagnosed by combining imaging modalities.

    PubMed

    Tachibana, Motomi; Mukouhara, Naoki; Hirami, Ryouichi; Fujio, Hideki; Yumoto, Akihisa; Watanuki, Yutaka; Hayashi, Aiko; Suminoe, Isao; Koudani, Hiroshi

    2013-01-01

    Congenital coronary pulmonary artery fistula (CAF) is rare, and systemic-to-pulmonary artery fistula (SPAF) is even more so. Furthermore, congenital coronary pulmonary fistula associated with congenital SPAF is extremely rare. As far as we know, CAF and SPAF connected with an aneurysm have not been described very often. We described an 83-year-old woman with an aneurysm originating from a CAF connected to an aortopulmonary artery fistula. Chest radiography revealed a shadow at the left edge of the heart line. Multi-detector-row computed tomography (MDCT) with contrast enhancement and coronary cine angiography revealed that the shadow was an aneurysm connected to a tortuous fistula at the left anterior descending coronary artery. The aneurysm was formed by congenital coronary pulmonary and aortopulmonary artery fistulae. Echocardiography revealed predominantly systolic blood flow in the fistula from the left anterior descending coronary artery (LAD). Although neither MDCT, echocardiography nor coronary angiography alone could provide a comprehensive image of the anomaly, including the hemodynamics in the fistulae and their relationship with surrounding organs and tissues, their combination could provided important facts the led to a deeper understanding of this very uncommon occurrence. PMID:24145730

  10. Hepatic artery thrombosis after orthotopic liver transplantation: 3 patients with collateral formation and conservative treatment.

    PubMed

    Fouzas, I; Sklavos, A; Bismpa, K; Paxiadakis, I; Antoniadis, N; Giakoustidis, D; Katsiki, E; Tatsou, N; Mouloudi, E; Karapanagiotou, A; Tsitlakidis, A; Karakatsanis, A; Patsiaoura, K; Petridis, A; Gakis, D; Imvrios, G; Papanikolaou, V

    2012-11-01

    Hepatic artery thrombosis (HAT), a serious complication after orthotopic liver transplantation (OLT), can lead to patient death in the absence of revascularization or retransplantation. Herein we have presented clinical characteristics, imaging findings, and long-term outcomes of 3 OLT patients with HAT who were treated conservatively and developed hepatic arterial collaterals. These patients underwent transplantation due to hepatitis B cirrhosis, cryptogenic cirrhosis, or hepatitis C infection and alcoholic disease. They presented with bile duct stenosis and/or a bile leak at 1, 3, and 36 months after transplantation, respectively, and were treated with percutaneous drainage and stent placement, endoscopic retrograde cholangio-pancreatography (ERCP), or reanastomosis of the bile duct over a T tube. HAT was confirmed using multidetector computed tomography (MDCT) 3-dimensional (3D) angiography and Doppler sonography. They survive in good condition with normal liver function at 30, 50, and 42 months after OLT, respectively. Development of collateral arterial circulation to the liver graft was detected with MDCT 3D angiography and Doppler sonography. From our experience with 3 patients and a literature review, we believe that there are a number of patients who experience long-term survival after the diagnosis of irreversible HAT and the development of collaterals. Although this group is at high risk for sepsis and biliary complications, these are usually self-limiting complications due to improved treatment regimens. The development of collateral arterial flow may also be beneficial.

  11. A three-dimensional reconstructive study of pelvic cavity in the New Zealand rabbit (Oryctolagus cuniculus).

    PubMed

    Özkadif, Sema; Eken, Emrullah; Kalaycı, Ibrahim

    2014-01-01

    The present study has been performed to reveal biometrical aspects and diameter-related differences in terms of sexes regarding pelvic cavity via three-dimensional (3D) reconstruction by using multidetector computed tomography (MDCT) images of pelvic cavity of the New Zealand rabbit. A total of 16 adult New Zealand rabbits, including 8 males and 8 females, were used in this study. Under anesthesia, the images obtained from MDCT were stacked and overlaid to reconstruct the 3D model of the pelvic cavity using 3D modeling software (Mimics 13.1). Measurements, such as the conjugate, transverse, and vertical diameters of the pelvic cavity, and the pelvic inclination were calculated and analyzed statistically. Biometrical differences of the pelvic diameters in New Zealand rabbits of both sexes were shown clearly. It was concluded that the pelvic diameters revealed by 3D modeling techniques can shed light on medical students who take both anatomy training and gynecological applications. The authors hope that the synchronization of medical approaches may give rise to novel diagnostic and therapeutic developments related to pelvic cavity.

  12. Application of three-dimensional computed tomography in craniofacial clinical practice and research.

    PubMed

    Anderson, P J; Yong, R; Surman, T L; Rajion, Z A; Ranjitkar, S

    2014-06-01

    Following the invention of the first computed tomography (CT) scanner in the early 1970s, many innovations in three-dimensional (3D) diagnostic imaging technology have occurred, leading to a wide range of applications in craniofacial clinical practice and research. Three-dimensional image analysis provides superior and more detailed information compared with conventional plain two-dimensional (2D) radiography, with the added benefit of 3D printing for preoperative treatment planning and regenerative therapy. Current state-of-the-art multidetector CT (MDCT), also known as medical CT, has an important role in the diagnosis and management of craniofacial injuries and pathology. Three-dimensional cone beam CT (CBCT), pioneered in the 1990s, is gaining increasing popularity in dental and craniofacial clinical practice because of its faster image acquisition at a lower radiation dose, but sound guidelines are needed to ensure its optimal clinical use. Recent innovations in micro-computed tomography (micro-CT) have revolutionized craniofacial biology research by enabling higher resolution scanning of teeth beyond the capabilities of MDCT and CBCT, presenting new prospects for translational clinical research. Even after four decades of refinement, CT technology continues to advance and broaden the horizons of craniofacial clinical practice and phenomics research. PMID:24611727

  13. PULMONARY ANGIOGRAPHY WITH 64-MULTIDETECTOR-ROW COMPUTED TOMOGRAPHY IN NORMAL DOGS

    PubMed Central

    Drees, Randi; Frydrychowicz, Alex; Keuler, Nicholas S.; Reeder, Scott B.; Johnson, Rebecca

    2012-01-01

    Pulmonary angiography using 64-multidetector-row computed tomography (MDCT) was used to evaluate pulmonary artery anatomy, and determine the sensitivity of pulmonary artery segment visualization in four Beagle dogs using images reconstructed to 0.625 mm and retro-reconstructed to 1.25 and 2.5 mm slice thickness. Morphologically, characteristic features included a focal narrowing in the right cranial pulmonary artery in all dogs, which should not be mistaken as stenosis. While the right cranial pulmonary artery divided into two equally sized branches that were tracked into the periphery of the lung lobe in all dogs, only a single left cranial (cranial portion) lobar artery was present. Compared with 1.25 and 2.5 mm retro-reconstructions, 0.625 mm reconstructions allowed for detection of significantly (P ≤ 0.05) more pulmonary artery segments and sharper depiction of vessel margins. Clinical applications such as prevalence and significance of diameter changes, and detection of pulmonary arterial thrombembolism on lobar and sublobar level, using pulmonary angiography with 64-MDCT applying 0.625 mm reconstruction slice thickness remain to be established. PMID:21545367

  14. Three-dimensional reconstruction of medieval child mummy in Yangju, Korea, using multi-detector computed tomography.

    PubMed

    Lee, In Sun; Kim, Myeung Ju; Yoo, Dong Soo; Lee, Young Seok; Park, Sung Sil; Bok, Gi Dae; Han, Seung Ho; Chung, Yoon Hee; Chang, Byung Soo; Yi, Yang Su; Oh, Chang Seok; Shin, Dong Hoon

    2007-01-01

    Recently reported studies on the medieval mummies in Korea have been regarded as an invaluable source for studying the physical characteristics of medieval Koreans. However, since the reported medieval mummies were re-buried by their descendants without any scientific investigations, the development of a brief, non-invasive investigation technique was desperately needed among the researchers in Korea. In this regard, we tried to apply high-quality multi-detector computed tomography (MDCT) with three-dimensional (3D) reconstructions and multi-planar reformat (MPR) to investigate Korean mummies. In our study, after 1.25 or 2.5mm thin slice axial images were taken, 3D reconstruction and MPR were performed to get more accurate information about internal organs. In this trial, we successfully showed high-quality images for the brain, muscles, bones, heart and liver. During various trials for getting selected organs, we could make the 3D reconstructed images of them. Since we could show that the current MDCT technique could be useful for obtaining high-quality 3D reconstructed images of the internal organs of Korean mummies, this technique will be used in forthcoming similar cases, which could not be investigated using invasive techniques.

  15. The Role of Virtual Cystoscopy, after Multidetector Computed Tomography Imaging Reconstruction without the Use of Contrast Medium, in the Diagnosis and Evaluations of Bladder Tumors: Preliminary Study.

    PubMed

    Kalokairinou, Kyriaki; Ploumidis, Achilles; Kalogeropoulos, Theodoros; Vlachos, Lampros; Stringaris, Kyriakos; Tavernaraki, Ageliki; Thanos, Anastasios; Papacharalampous, Xenofon; Koutoulidis, Vasilios; Letendre, Julien; Traxer, Olivier; Gouliamos, Athanasios

    2014-01-01

    Introduction. Although conventional cystoscopy is considered to be the gold standard for diagnosis and follow-up of bladder tumors, it remains an invasive and costly procedure. With the advent of the multidetector CT (MDCT) scanners supported by specialized software virtual cystoscopy (VC) is possible. We assess the role of VC in diagnosing and evaluating bladder lesions. Materials and Methods. Between September 2010 and October 2011, 25 consecutive patients with cystoscopically confirmed bladder tumor underwent VC. The radiologists involved in this prospective study were blinded to the exact findings. After draining any residual urine with a catheter, the bladder was retrogradely insufflated with 200-600 cc of air. No intravenous or intravesical contrast was used. MDCT scan was performed in supine and prone positions and three-dimensional reconstruction of the urinary bladder was performed. Results. The examination was well tolerated by all patients with no complications. In total, 43 lesions were detected both with conventional cystoscopy and VC. Tumor size measured by CT ranged from 3 to 80 mm in diameter. The pathological report revealed noninvasive transitional cell carcinomas in all cases. Conclusion. VC has promising results in detecting exophytic bladder lesions. In the future it could be part of the diagnostic algorithm for bladder tumors. PMID:24799894

  16. Urethroscrotal Fistula: A Rare Cause of Scrotal Swelling

    PubMed Central

    Parlak, Selcuk; Okay, Aysun E.

    2016-01-01

    Summary Background Urethroscrotal fistula (USF) is an abnormal communication between the urethra and the scrotum. This rare abnormality may be iatrogenic or secondary to perforation of the urethra by a stone. After the passage of urine to the scrotum through the fistula, painless scrotal swelling develops, which disappears completely with manual compression, and voiding can be maintained in this way. Retrograde urethrography (RU) and voiding cystourethrography (VCU) are traditional diagnostic methods, but they have limitations, such as technical difficulties and inability to evaluate the surrounding tissues. Multidetector CT (MDCT), together with reformatted images, can provide valuable information about the surrounding tissues and associated pathologies. Case Report We present a case of a 36-year-old male patient who had painless scrotal swelling after cystolithotomy and urethral stone surgery. The patient indicated that the swelling disappeared after manual compression. A fistula between the bulbous urethra and the scrotum was discovered by MDCT. In our case, we believe that the fistula developed iatrogenically during stone excision or secondary to perforation of the urethra by a stone. Conclusions As a rare pathology, urethroscrotal fistula should be considered in men with a history of urethral stone surgery and symptoms, including painless scrotal swelling, which can be manually compressed after voiding. PMID:27668028

  17. Evaluation of bone substitute materials: comparison of flat-panel based volume CT to conventional multidetector CT.

    PubMed

    Sauerbier, Sebastian; Duttenhoefer, Fabian; Sachlos, Elefterios; Haberstroh, Jörg; Scheifele, Christian; Wrbas, Karl-Thomas; Voss, Pit Jacob; Veigel, Egle; Smedek, Jörg; Ganter, Philip; Tuna, Taskin; Gutwald, Ralf; Palmowski, Moritz

    2013-10-01

    Over the last decade tissue engineering has emerged as a key factor in bone regeneration within the field of cranio-maxillofacial surgery. Despite this in vivo analysis of tissue-engineered-constructs to monitor bone rehabilitation are difficult to conduct. Novel high-resolving flat-panel based volume CTs (fp-VCT) are increasingly used for imaging bone structures. This study compares the potential value of novel fp-VCT with conventional multidetector CT (MDCT) based on a sheep sinus floor elevation model. Calcium-hydroxyapatite reinforced collagen scaffolds were populated with autologous osteoblasts and implanted into sheep maxillary sinus. After 8, 16 and 24 weeks MDCT and fp-VCT scans were performed to investigate the volume of the augmented area; densities of cancellous and compact bone were assessed as comparative values. fp-VCT imaging resulted in higher spatial resolution, which was advantageous when separating closely related anatomical structures (i.e. trabecular and compact bone, biomaterials). Fp-VCT facilitated imaging of alterations occurring in test specimens over time. fp-VCTs therefore displayed high volume coverage, dynamic imaging potential and superior performance when investigating superfine bone structures and bone remodelling of biomaterials. Thus, fp-VCTs may be a suitable instrument for intraoperative imaging and future in vivo tissue-engineering studies.

  18. Multislice CT perfusion imaging of the lung in detection of pulmonary embolism

    NASA Astrophysics Data System (ADS)

    Hong, Helen; Lee, Jeongjin

    2006-03-01

    We propose a new subtraction technique for accurately imaging lung perfusion and efficiently detecting pulmonary embolism in chest MDCT angiography. Our method is composed of five stages. First, optimal segmentation technique is performed for extracting same volume of the lungs, major airway and vascular structures from pre- and post-contrast images with different lung density. Second, initial registration based on apex, hilar point and center of inertia (COI) of each unilateral lung is proposed to correct the gross translational mismatch. Third, initial alignment is refined by iterative surface registration. For fast and robust convergence of the distance measure to the optimal value, a 3D distance map is generated by the narrow-band distance propagation. Fourth, 3D nonlinear filter is applied to the lung parenchyma to compensate for residual spiral artifacts and artifacts caused by heart motion. Fifth, enhanced vessels are visualized by subtracting registered pre-contrast images from post-contrast images. To facilitate visualization of parenchyma enhancement, color-coded mapping and image fusion is used. Our method has been successfully applied to ten patients of pre- and post-contrast images in chest MDCT angiography. Experimental results show that the performance of our method is very promising compared with conventional methods with the aspects of its visual inspection, accuracy and processing time.

  19. Lymph nodes metastasis of gastric cancer: Measurement with multidetector CT oblique multiplanar reformation-correlation with histopathologic results.

    PubMed

    Wang, Zhi-Long; Zhang, Xiao-Peng; Tang, Lei; Li, Xiao-Ting; Wu, Ying; Sun, Ying-Shi

    2016-09-01

    The aim of this study was to retrospectively evaluate the ability of multidetector computed tomography (MDCT) oblique multiplanar reformation (MPR) for differentiating metastatic lymph nodes (LNs) in patients with gastric cancer.Seventy-nine patients with gastric cancer underwent preoperative computed tomography (CT). One-to-one correlation of LN was made between CT oblique multiplanar reformation and histopathologic slides. Long diameters, short diameters, and short-to-long axis ratios of LNs were evaluated to differentiate metastasis.Short diameters of nodes performed better for diagnosing metastasis than long diameters and short-to-long ratios. Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve of short diameter were 57.8%, 74.7%, 68.2%, and 0.713, respectively. With different thresholds of short diameters of nodes (No. 8 group >6 mm and other groups >4 mm), total sensitivity, specificity, and accuracy can reach 57.2%, 79.0%, and 70.3%, respectively.MDCT oblique MPR images have certain reference value to distinguish metastasis of LNs in gastric cancer. The diagnostic power for LN metastasis of gastric cancer can be improved by using different threshold for No. 8 group LNs and other groups. PMID:27684881

  20. CBCT-based bone quality assessment: are Hounsfield units applicable?

    PubMed Central

    Jacobs, R; Singer, S R; Mupparapu, M

    2015-01-01

    CBCT is a widely applied imaging modality in dentistry. It enables the visualization of high-contrast structures of the oral region (bone, teeth, air cavities) at a high resolution. CBCT is now commonly used for the assessment of bone quality, primarily for pre-operative implant planning. Traditionally, bone quality parameters and classifications were primarily based on bone density, which could be estimated through the use of Hounsfield units derived from multidetector CT (MDCT) data sets. However, there are crucial differences between MDCT and CBCT, which complicates the use of quantitative gray values (GVs) for the latter. From experimental as well as clinical research, it can be seen that great variability of GVs can exist on CBCT images owing to various reasons that are inherently associated with this technique (i.e. the limited field size, relatively high amount of scattered radiation and limitations of currently applied reconstruction algorithms). Although attempts have been made to correct for GV variability, it can be postulated that the quantitative use of GVs in CBCT should be generally avoided at this time. In addition, recent research and clinical findings have shifted the paradigm of bone quality from a density-based analysis to a structural evaluation of the bone. The ever-improving image quality of CBCT allows it to display trabecular bone patterns, indicating that it may be possible to apply structural analysis methods that are commonly used in micro-CT and histology. PMID:25315442

  1. A huge saccular aortic aneurysm compressing right coronary artery 7 years after aortic valve replacement due to bicuspid aortic valve insufficiency

    PubMed Central

    Park, Sang Min; Jeong, Haemin; Hong, Kyung-Soon; Kim, Christopher

    2016-01-01

    Abstract Background: In a patient underwent aortic valve replacement (AVR) due to bicuspid aortic valve (BAV) insufficiency without marked dilation of ascending aorta, the development of delayed-typed aneurysmal complication of ascending aorta has been often reported because the dilated aorta tends to grow insidiously with age. Case summary: A 58-year-old man who underwent AVR with mechanical valve due to severe aortic regurgitation secondary to BAV 7 years previously presented with exertional chest discomfort for 1 year. An echocardiography showed a well-functioning mechanical aortic valve without any significant abnormal findings. Cardiac multidetector computed tomography (MDCT) revealed a huge saccular aortic root aneurysm (79.7 mm × 72.8 mm in size) compressing the proximal right coronary artery resulting in ∼90% eccentric diffuse luminal narrowing. The patient subsequently underwent open-heart surgery with resection of the ascending aortic aneurysmal sac and consecutive ascending aorta and hemi-arch replacement using a graft. Conclusion: After successful AVR in the patient with BAV insufficiency and mildly dilated ascending aorta, a regular aortic imaging such as cardiac MDCT with aortography would be helpful to monitor the morphology and size of ascending aorta and related complications to guide future management. PMID:27749539

  2. Optimising the scan delay for arterial phase imaging of the liver using the bolus tracking technique

    PubMed Central

    Chan, RS; Kumar, G; Abdullah, BJJ; Ng, KH; Vijayananthan, A; Mohd. Nor, H; Liew, YW

    2011-01-01

    Objective: To optimize the delay time before the initiation of arterial phase scan in the detection of focal liver lesions in contrast enhanced 5 phase liver CT using the bolus tracking technique. Patients and Methods: Delay - the interval between threshold enhancement of 100 hounsfield unit (HU) in the abdominal aorta and commencement of the first arterial phase scan. Using a 16 slice CT scanner, a plain CT of the liver was done followed by an intravenous bolus of 120 ml nonionic iodinated contrast media (370 mg I/ml) at the rate of 4 mL/s. The second phase scan started immediately after the first phase scan. The portal venous and delay phases were obtained at a fixed delay of 60 s and 90 s from the beginning of contrast injection. Contrast enhancement index (CEI) and subjective visual conspicuity scores for each lesion were compared among the three groups. Results: 84 lesions (11 hepatocellular carcinomas, 17 hemangiomas, 39 other hypervascular lesions and 45 cysts) were evaluated. CEI for hepatocellular carcinomas appears to be higher during the first arterial phase in the 6 seconds delay group. No significant difference in CEI and mean conspicuity scores among the three groups for hemangioma, other hypervascular lesions and cysts. Conclusion: The conspicuity of hepatocellular carcinomas appeared better during the early arterial phase using a bolus tracking technique with a scan delay of 6 seconds from the 100 HU threshold in the abdominal aorta. PMID:22287986

  3. [Examination of motion artifacts for helical and non-helical scanning modes in head CT].

    PubMed

    Fujimura, Ichiro; Ichikawa, Katsuhiro; Terakawa, Shoichi; Hara, Takanori; Miura, Yohei

    2011-01-01

    For head computed tomography (CT), non-helical scanning has been recommended even in the widely used multi-slice CT (MSCT). Also, an acute stroke imaging standardization group has recommended the non-helical mode in Japan. However, no detailed comparison has been reported for current MSCT with more than 16 slices. In this study, we compared the non-helical and helical modes for head CT, focusing on temporal resolution and motion artifacts. The temporal resolution was evaluated by using temporal sensitivity profiles (TSPs) measured using a temporal impulse method. In both modes, the TSPs and temporal modulation transfer factors (MTFs) were measured for various pitch factors using 64-slice CT (Aquilion 64, Toshiba). Two motion phantoms were scanned to evaluate motion artifacts, and then quantitative analyses for motion artifacts and helical artifacts were performed by measuring multiple regions of interest (ROIs) in the phantom images. In addition, the rates of artifact occurrence for retrospective clinical cases were compared. The temporal resolution increased as the pitch factor was increased. Remarkable streak artifacts appeared in the non-helical images of the motion phantom, in spite of the equivalent effective temporal resolution. In clinical analysis, results consistent with the phantom studies were shown. These results indicated that the low pitch helical mode would be effective for emergency head CT with patient movement.

  4. Cardiac cone-beam CT volume reconstruction using ART

    SciTech Connect

    Nielsen, T.; Manzke, R.; Proksa, R.; Grass, M.

    2005-04-01

    Modern computed tomography systems allow volume imaging of the heart. Up to now, approximately two-dimensional (2D) and 3D algorithms based on filtered backprojection are used for the reconstruction. These algorithms become more sensitive to artifacts when the cone angle of the x-ray beam increases as it is the current trend of computed tomography (CT) technology. In this paper, we investigate the potential of iterative reconstruction based on the algebraic reconstruction technique (ART) for helical cardiac cone-beam CT. Iterative reconstruction has the advantages that it takes the cone angle into account exactly and that it can be combined with retrospective cardiac gating fairly easily. We introduce a modified ART algorithm for cardiac CT reconstruction. We apply it to clinical cardiac data from a 16-slice CT scanner and compare the images to those obtained with a current analytical reconstruction method. In a second part, we investigate the potential of iterative reconstruction for a large area detector with 256 slices. For the clinical cases, iterative reconstruction produces excellent images of diagnostic quality. For the large area detector, iterative reconstruction produces images superior to analytical reconstruction in terms of cone-beam artifacts.

  5. Automatic phase determination for retrospectively gated cardiac CT

    SciTech Connect

    Manzke, R.; Koehler, Th.; Nielsen, T.; Hawkes, D.; Grass, M.

    2004-12-01

    The recent improvements in CT detector and gantry technology in combination with new heart rate adaptive cone beam reconstruction algorithms enable the visualization of the heart in three dimensions at high spatial resolution. However, the finite temporal resolution still impedes the artifact-free reconstruction of the heart at any arbitrary phase of the cardiac cycle. Cardiac phases must be found during which the heart is quasistationary to obtain outmost image quality. It is challenging to find these phases due to intercycle and patient-to-patient variability. Electrocardiogram (ECG) information does not always represent the heart motion with an adequate accuracy. In this publication, a simple and efficient image-based technique is introduced which is able to deliver stable cardiac phases in an automatic and patient-specific way. From low-resolution four-dimensional data sets, the most stable phases are derived by calculating the object similarity between subsequent phases in the cardiac cycle. Patient-specific information about the object motion can be determined and resolved spatially. This information is used to perform optimized high-resolution reconstructions at phases of little motion. Results based on a simulation study and three real patient data sets are presented. The projection data were generated using a 16-slice cone beam CT system in low-pitch helical mode with parallel ECG recording.

  6. Incidental Computer Tomography Radiologic Findings through Research Participation in the North Texas Healthy Heart Study

    PubMed Central

    Espinoza, Anna; Malone, Kendra; Balyakina, Elizabeth; Fulda, Kimberly G.; Cardarelli, Roberto

    2014-01-01

    Background Although variation exists in the classification and practice of managing clinical findings in research, emerging views suggest that researchers bear some responsibility in the management of incidental findings. This study contributes to the documentation of the population characteristics and prevalence of medical findings incidental to research participation, specifically findings related to coronary calcium scores and computed tomography (CT) scans that investigated cardiovascular disparities in an asymptomatic population. Methods A total of 571 asymptomatic adult participants were recruited in the North Texas Healthy Heart Study. Participants completed a 16-slice CT scan of the heart and abdomen. Findings of radiology reports and 3 years of follow-up documentation were reviewed. Results A total of 246 clinically apparent findings were identified in 169 asymptomatic participants (32.9% of participants who completed a CT scan). Another 245 participants (48%) had findings of unknown significance, a total of 307 findings. At least 4 cases in this study led to a clinically significant intervention. Conclusion Although CT scans were completed for research purposes, study procedures resulted in the diagnosis and treatment of individuals who were previously asymptomatic. Potential clinical benefits in imaging research are moderated by considerations regarding possible harm and costs resulting from uncertain findings and the use of CT scans for nonclinical purposes. The continued development of protocols for the handling of incidental findings in research and the establishment of guidelines are needed to ensure that research procedures mirror the best interests of participants. PMID:24808109

  7. Evaluation of a low-dose/slow-rotating SPECT-CT system

    NASA Astrophysics Data System (ADS)

    Hamann, M.; Aldridge, M.; Dickson, J.; Endozo, R.; Lozhkin, K.; Hutton, B. F.

    2008-05-01

    The 4-slice CT that forms part of the GE Infinia Hawkeye-4 SPECT-CT scanner (Hawkeye) is evaluated against the diagnostic 16-slice CT that is incorporated in the GE Discovery ST PET-CT system (DST). The x-ray tube of the slow-rotating Hawkeye system (23 s/rotation) operates at approximately a third of the dose of diagnostic systems as used for conventional diagnostic imaging. Image reconstruction is optimized for low noise. High-contrast spatial resolution significantly falls behind diagnostic figures: the average of MTF50 and MTF10 (resolution where the MTF has fallen to 50% and 10%) is 2.8 ± 0.1 cm-1 for Hawkeye and 5.3 ± 0.1 cm-1 for the DST (standard reconstruction filters). Resolution in the direction of the couch movement (z coordinate) is governed by the fixed Hawkeye slice width of 5 mm. Reconstruction accuracy is found to be increased by reducing the default z increment from 4.4 mm to 2.2 mm. Low-contrast object detectability is superior compared with diagnostic systems operating in the Hawkeye dose range. In the diagnostic dose regime, however, small low-contrast details remain visible in DST that are not detectable with Hawkeye. Although not of diagnostic quality, the low-dose Hawkeye provides appropriate data for SPECT attenuation correction and anatomical localization capability. For more information on this article, see medicalphysicsweb.org

  8. Serial CT features of pulmonary leptospirosis in 10 dogs.

    PubMed

    Gendron, K; Christe, A; Walter, S; Schweighauser, A; Francey, T; Doherr, M G; Lang, J

    2014-02-15

    Leptospirosis pulmonary haemorrhage syndrome (LPHS) is a frequent manifestation of Leptospira infection in dogs and is associated with a high morbidity and mortality. Three helical 16-slice thoracic CT scans were performed in 10 dogs naturally infected with Leptospira, within 24 hours of admission, and three and seven days later. Patients were sedated and scanned without breathhold, with a protocol adapted for rapid scanning. One dog died of respiratory failure on the morning following the first scan. On the initial scan, imaging features of LPHS included ground-glass nodules (10/10), peribronchovascular interstitial thickening (10/10), diffuse or patchy ground-glass opacity (9/10), solid nodules (8/10) and consolidation (7/10). Temporary bronchiolar dilation was observed in all dogs in association with peribronchovascular interstitial thickening, which had completely resolved at day 7. Nodules were with few exceptions assigned to the centrilobular region. Regression of lesion severity was observed after each subsequent scan. Consolidation and solid nodules changed over time into lesions of ground-glass attenuation. Pleural effusion (3/10) and mediastinal effusion (2/10) were mild and transient. Lesion severity appeared unassociated with survival to discharge. PMID:24420873

  9. Cervix carcinoma and incidental finding of medullary thyroid carcinoma by 18F-FDG PET/CT--clinical case.

    PubMed

    Chaushev, Borislav; Bochev, Pavel; Klisarova, Anelia; Yordanov, Kaloyan; Encheva, Elitsa; Dancheva, Jivka; Yordanova, Cvetelina; Hristozov, Kiril; Krasnaliev, Ivan; Radev, Radoslav; Nenkov, Rumen

    2014-01-01

    Thyroid nodules are encountered in clinical practice during the diagnostic procedures or patients' follow-up due to other diseases quite far from the thyroid gland with prevalence 4-50% in general population, depending on age, diagnostic method and race. The prevalence of thyroid nodules increases with age and their clarification should be done for their adequate treatment. An 18F-FDG PET/CT was done with a PET/CT scanner (Philips Gemini TF), consisting of dedicated lutetium orthosilicate full ring PET scanner and 16 slice CT. The PET/CT scan of the whole-body revealed on the CT portion a hypodense nodular lesion in the left lobe of the thyroid gland with increased uptake of 18F-FDG on the PET with SUVmax 10.3 and demonstrated a complete response to the induction therapy of the main oncological disease of the patient--squamous cell carcinoma. This clinical case demonstrates that whole-body 18F-FDG-PET/CT has an increasingly important role in the early evaluation of thyroid cancer as a second independent malignant localization. Focal thyroid lesion with high risk of thyroid malignancy was incidentally found on 18F-FDG PET/CT. PMID:25088110

  10. Deltoid muscle shape analysis with magnetic resonance imaging in patients with chronic rotator cuff tears

    PubMed Central

    2013-01-01

    Background It seems appropriate to assume, that for a full and strong global shoulder function a normally innervated and active deltoid muscle is indispensable. We set out to analyse the size and shape of the deltoid muscle on MR-arthrographies, and analyse its influence on shoulder function and its adaption (i.e. atrophy) for reduced shoulder function. Methods The fatty infiltration (Goutallier stages), atrophy (tangent sign) and selective myotendinous retraction of the rotator cuff, as well as the thickness and the area of seven anatomically defined segments of the deltoid muscle were measured on MR-arthrographies and correlated with shoulder function (i.e. active abduction). Included were 116 patients, suffering of a rotator cuff tear with shoulder mobility ranging from pseudoparalysis to free mobility. Kolmogorov-Smirnov test was used to determine the distribution of the data before either Spearman or Pearson correlation and a multiple regression was applied to reveal the correlations. Results Our developed method for measuring deltoid area and thickness showed to be reproducible with excellent interobserver correlations (r = 0.814–0.982). The analysis of influencing factors on active abduction revealed a weak influence of the amount of SSP tendon (r = −0.25; p < 0.01) and muscle retraction (r = −0.27; p < 0.01) as well as the stage of fatty muscle infiltration (GFDI: r = −0.36; p < 0.01). Unexpectedly however, we were unable to detect a relation of the deltoid muscle shape with the degree of active glenohumeral abduction. Furthermore, long-standing rotator cuff tears did not appear to influence the deltoid shape, i.e. did not lead to muscle atrophy. Conclusions Our data support that in chronic rotator cuff tears, there seems to be no disadvantage to exhausting conservative treatment and to delay implantation of reverse total shoulder arthroplasty, as the shape of deltoid muscle seems only to be influenced by natural aging

  11. Rectal cancer staging: Multidetector-row computed tomography diagnostic accuracy in assessment of mesorectal fascia invasion

    PubMed Central

    Ippolito, Davide; Drago, Silvia Girolama; Franzesi, Cammillo Talei; Fior, Davide; Sironi, Sandro

    2016-01-01

    AIM: To assess the diagnostic accuracy of multidetector-row computed tomography (MDCT) as compared with conventional magnetic resonance imaging (MRI), in identifying mesorectal fascia (MRF) invasion in rectal cancer patients. METHODS: Ninety-one patients with biopsy proven rectal adenocarcinoma referred for thoracic and abdominal CT staging were enrolled in this study. The contrast-enhanced MDCT scans were performed on a 256 row scanner (ICT, Philips) with the following acquisition parameters: tube voltage 120 KV, tube current 150-300 mAs. Imaging data were reviewed as axial and as multiplanar reconstructions (MPRs) images along the rectal tumor axis. MRI study, performed on 1.5 T with dedicated phased array multicoil, included multiplanar T2 and axial T1 sequences and diffusion weighted images (DWI). Axial and MPR CT images independently were compared to MRI and MRF involvement was determined. Diagnostic accuracy of both modalities was compared and statistically analyzed. RESULTS: According to MRI, the MRF was involved in 51 patients and not involved in 40 patients. DWI allowed to recognize the tumor as a focal mass with high signal intensity on high b-value images, compared with the signal of the normal adjacent rectal wall or with the lower tissue signal intensity background. The number of patients correctly staged by the native axial CT images was 71 out of 91 (41 with involved MRF; 30 with not involved MRF), while by using the MPR 80 patients were correctly staged (45 with involved MRF; 35 with not involved MRF). Local tumor staging suggested by MDCT agreed with those of MRI, obtaining for CT axial images sensitivity and specificity of 80.4% and 75%, positive predictive value (PPV) 80.4%, negative predictive value (NPV) 75% and accuracy 78%; while performing MPR the sensitivity and specificity increased to 88% and 87.5%, PPV was 90%, NPV 85.36% and accuracy 88%. MPR images showed higher diagnostic accuracy, in terms of MRF involvement, than native axial images

  12. Comparison of biophysical factors influencing on emphysema quantification with low-dose CT

    NASA Astrophysics Data System (ADS)

    Heo, Chang Yong; Kim, Jong Hyo

    2014-03-01

    Emphysema Index(EI) measurements in MDCT is known to be influenced by various biophysical factors such as total lung volume, and body size. We investigated the association of the four biophysical factors with emphysema index in low-dose MDCT. In particular, we attempted to identify a potentially stronger biophysical factor than total lung volume. A total of 400 low-dose MDCT volumes taken at 120kVp, 40mAs, 1mm thickness, and B30f reconstruction kernel were used. The lungs, airways, and pulmonary vessels were automatically segmented, and two Emphysema Indices, relative area below -950HU(RA950) and 15th percentile(Perc15), were extracted from the segmented lungs. The biophysical factors such as total lung volume(TLV), mode of lung attenuation(ModLA), effective body diameter(EBD), and the water equivalent body diameter(WBD) were estimated from the segmented lung and body area. The association of biophysical factors with emphysema indices were evaluated by correlation coefficients. The mean emphysema indices were 8.3±5.5(%) in RA950, and -930±18(HU) in Perc15. The estimates of biophysical factors were 4.7±1.0(L) in TLV, -901±21(HU) in ModLA, 26.9±2.2(cm) in EBD, and 25.9±2.6(cm) in WBD. The correlation coefficients of biophysical factors with RA950 were 0.73 in TLV, 0.94 in ModLA, 0.31 in EBD, and 0.18 WBD, the ones with Perc15 were 0.74 in TLV, 0.98 in ModLA, 0.29 in EBD, and 0.15 WBD. Study results revealed that two biophysical factors, TLV and ModLA, mostly affects the emphysema indices. In particular, the ModLA exhibited strongest correlation of 0.98 with Perc15, which indicating the ModLA is the most significant confounding biophysical factor in emphysema indices measurement.

  13. Estimating radiation dose to organs of patients undergoing conventional and novel multidetector CT exams using Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Angel, Erin

    Advances in Computed Tomography (CT) technology have led to an increase in the modality's diagnostic capabilities and therefore its utilization, which has in turn led to an increase in radiation exposure to the patient population. As a result, CT imaging currently constitutes approximately half of the collective exposure to ionizing radiation from medical procedures. In order to understand the radiation risk, it is necessary to estimate the radiation doses absorbed by patients undergoing CT imaging. The most widely accepted risk models are based on radiosensitive organ dose as opposed to whole body dose. In this research, radiosensitive organ dose was estimated using Monte Carlo based simulations incorporating detailed multidetector CT (MDCT) scanner models, specific scan protocols, and using patient models based on accurate patient anatomy and representing a range of patient sizes. Organ dose estimates were estimated for clinical MDCT exam protocols which pose a specific concern for radiosensitive organs or regions. These dose estimates include estimation of fetal dose for pregnant patients undergoing abdomen pelvis CT exams or undergoing exams to diagnose pulmonary embolism and venous thromboembolism. Breast and lung dose were estimated for patients undergoing coronary CTA imaging, conventional fixed tube current chest CT, and conventional tube current modulated (TCM) chest CT exams. The correlation of organ dose with patient size was quantified for pregnant patients undergoing abdomen/pelvis exams and for all breast and lung dose estimates presented. Novel dose reduction techniques were developed that incorporate organ location and are specifically designed to reduce close to radiosensitive organs during CT acquisition. A generalizable model was created for simulating conventional and novel attenuation-based TCM algorithms which can be used in simulations estimating organ dose for any patient model. The generalizable model is a significant contribution of this

  14. Development of CT scanner models for patient organ dose calculations using Monte Carlo methods

    NASA Astrophysics Data System (ADS)

    Gu, Jianwei

    There is a serious and growing concern about the CT dose delivered by diagnostic CT examinations or image-guided radiation therapy imaging procedures. To better understand and to accurately quantify radiation dose due to CT imaging, Monte Carlo based CT scanner models are needed. This dissertation describes the development, validation, and application of detailed CT scanner models including a GE LightSpeed 16 MDCT scanner and two image guided radiation therapy (IGRT) cone beam CT (CBCT) scanners, kV CBCT and MV CBCT. The modeling process considered the energy spectrum, beam geometry and movement, and bowtie filter (BTF). The methodology of validating the scanner models using reported CTDI values was also developed and implemented. Finally, the organ doses to different patients undergoing CT scan were obtained by integrating the CT scanner models with anatomically-realistic patient phantoms. The tube current modulation (TCM) technique was also investigated for dose reduction. It was found that for RPI-AM, thyroid, kidneys and thymus received largest dose of 13.05, 11.41 and 11.56 mGy/100 mAs from chest scan, abdomen-pelvis scan and CAP scan, respectively using 120 kVp protocols. For RPI-AF, thymus, small intestine and kidneys received largest dose of 10.28, 12.08 and 11.35 mGy/100 mAs from chest scan, abdomen-pelvis scan and CAP scan, respectively using 120 kVp protocols. The dose to the fetus of the 3 month pregnant patient phantom was 0.13 mGy/100 mAs and 0.57 mGy/100 mAs from the chest and kidney scan, respectively. For the chest scan of the 6 month patient phantom and the 9 month patient phantom, the fetal doses were 0.21 mGy/100 mAs and 0.26 mGy/100 mAs, respectively. For MDCT with TCM schemas, the fetal dose can be reduced with 14%-25%. To demonstrate the applicability of the method proposed in this dissertation for modeling the CT scanner, additional MDCT scanner was modeled and validated by using the measured CTDI values. These results demonstrated that the

  15. Evaluation of the Elekta Symmetry ™ 4D IGRT system by using a moving lung phantom

    NASA Astrophysics Data System (ADS)

    Shin, Hun-Joo; Kim, Shin-Wook; Kay, Chul Seung; Seo, Jae-Hyuk; Lee, Gi-Woong; Kang, Ki-Mun; Jang, Hong Seok; Kang, Young-nam

    2015-07-01

    Purpose: 4D cone-beam computed tomography (CBCT) is a beneficial tool for the treatment of movable tumors because it can help us to understand where the tumors are actually located and it has a precise treatment plan. However, general CBCT images have a limitation in that they cannot perfectly perform a sophisticated registration. On the other hand, the Symmetry TM 4D image-guided radiation therapy (IGRT) system of Elekta offers a 4D CBCT registration option. In this study, we evaluated the usefulness of Symmetry TM . Method and Materials: Planning CT images of the CIRS moving lung phantom were acquired 4D multi-detector CT (MDCT), and the images were sorted as 10 phases from 0% phase to 90% phase. The thickness of the CT images was 1 mm. Acquired MDCT images were transferred to the contouring software, and a virtual target was generated. A one-arc volumetric-modulated arc therapy (VMAT) plan was performed by using the treatment planning system on the virtual target. Finally, the movement of the phantom was verified by using the XVI Symmetry TM system. Results: The physical movement of the CIRS moving lung phantom was ±10.0 mm in the superiorinferior direction, ±1.0 mm in the lateral direction, and ±2.5 mm in the anterior-posterior direction. The movement of the phantom was measured from the 4D MDCT registration as ±10.2 mm in the superior-inferior direction, ±0.9 mm in the lateral direction, and ±2.45 mm in the anterior-posterior direction. The movement of the phantom was measured from the SymmetryTM registration as ±10.1 mm in the superior-inferior direction, ±0.9 mm in the lateral direction, and ±2.4 mm in the anterior-posterior direction. Conclusion: We confirmed that 4D CBCT is a beneficial tool for the treatment of movable tumors, and that the 4D registration of SymmetryTM can increase the precision of the registration when a movable tumor is the target of radiation treatment.

  16. Gastrointestinal stenting: Current status and imaging features.

    PubMed

    Malgras, B; Lo Dico, R; Pautrat, K; Dohan, A; Boudiaf, M; Pocard, M; Soyer, P

    2015-06-01

    The use of stents in the gastrointestinal tract has been subjected to major changes. Initially, the use of stents was restricted to malignant strictures in patients with metastatic disease. But thanks to reduction of the morbidity and mortality rates, they are now used with curative intention and in patients with benign diseases after careful selection. However, for patients presenting with colon obstruction due to an advanced colon carcinoma, the mortality and morbidity are still high. The purpose of this review is to provide an overview of indications, techniques and further developments of the stents in the gastrointestinal tract and to highlight the predominant role of multidetector row computed tomography (MDCT) in the detection of potential complications. PMID:25953525

  17. High resolution multidetector CT aided tissue analysis and quantification of lung fibrosis

    NASA Astrophysics Data System (ADS)

    Zavaletta, Vanessa A.; Karwoski, Ronald A.; Bartholmai, Brian; Robb, Richard A.

    2006-03-01

    Idiopathic pulmonary fibrosis (IPF, also known as Idiopathic Usual Interstitial Pneumontis, pathologically) is a progressive diffuse lung disease which has a median survival rate of less than four years with a prevalence of 15-20/100,000 in the United States. Global function changes are measured by pulmonary function tests and the diagnosis and extent of pulmonary structural changes are typically assessed by acquiring two-dimensional high resolution CT (HRCT) images. The acquisition and analysis of volumetric high resolution Multi-Detector CT (MDCT) images with nearly isotropic pixels offers the potential to measure both lung function and structure. This paper presents a new approach to three dimensional lung image analysis and classification of normal and abnormal structures in lungs with IPF.

  18. [Review of pre- and post-treatment multidetector computed tomography findings in abdominal aortic aneurysms].

    PubMed

    Casula, E; Lonjedo, E; Cerverón, M J; Ruiz, A; Gómez, J

    2014-01-01

    The increase in the frequency of abdominal aortic aneurysms (AAA) and the widely accepted use of endovascular aneurysm repair (EVAR) as a first-line treatment or as an alternative to conventional surgery make it necessary for radiologists to have thorough knowledge of the pre- and post-treatment findings. The high image quality provided by multidetector computed tomography (MDCT) enables CT angiography to play a fundamental role in the study of AAA and in planning treatment. The objective of this article is to review the cases of AAA in which CT angiography was the main imaging technique, so that radiologists will be able to detect the signs related to this disease, to diagnose it, to plan treatment, and to detect complications in the postoperative period. PMID:23489768

  19. [Recommendations for radiological diagnosis and assessment of treatment response in lung cancer: a national consensus statement by the Spanish Society of Medical Radiology and the Spanish Society of Medical Oncology].

    PubMed

    Ferreirós, J; Cabeza, B; Gayete, Á; Sánchez, M; Torres, M I; Cobo, M; Isla, D; Puente, J; Reguart, N; de Castro, J

    2015-01-01

    The last decade has seen substantial progress in the diagnostic and therapeutic approach to lung cancer, thus meaning that its prognosis has improved. The Spanish Society of Medical Radiology (SERAM) and the Spanish Society of Medical Oncology (SEOM) have therefore produced a national consensus statement in order to make recommendations for radiological diagnosis and assessment of treatment response in patients with lung cancer. This expert group recommends multi-detector computed tomography (MDCT) as the technique of choice for investigating this disease. The radiology report should include a full assessment by the TNM staging system. Lastly, when the patient is on immunotherapy, response evaluation should employ not only Response Evaluation Criteria in Solid Tumours (RECIST 1.1) but also Immune-Related Response Criteria (irRC). PMID:25530188

  20. Diagnosis of High Bifurcation of the Abdominal Aorta with Associated Vascular Variations: Case Report with Multidedector Computed Tomography

    PubMed Central

    Atalar, Mehmet Haydar; Salk, Ismail; Bozbiyik, Nisa; Cetin, Ali

    2015-01-01

    Summary Background Variations of the branches and bifurcation of the abdominal aorta and their relations with other abdominal structures and organs are important concerning abdominal and spinal surgery. Case Report In this report, authors present a high -positioned bifurcation of the abdominal aorta at the level of the L3 vertebral body and its associations with multiple variations of other abdominal arteries during contrast-enhanced multi-detector computed tomography (MDCT) examination of the abdomen. Conclusions We reported on a unique clinically and surgically significant case of variations of the abdominal aorta as related to the location and type of bifurcation. The awareness of the variations of the abdominal aorta is of great importance for surgeons in order to reduce complications during abdominal and spinal interventions, as well as for radiologists for precise interpretation of angiograms. PMID:26688701

  1. Imaging of the heart with computed tomography.

    PubMed

    Flohr, Thomas G; Ohnesorge, Bernd M

    2008-03-01

    Imaging of the heart with computed tomography (CT) was already introduced in the 1980Is and has meanwhile entered clinical routine as a consequence of the rapid evolution of CT technology during the last decade. In this review article, we give an overview on the technology and clinical performance of different CT-scanner generations used for cardiac imaging, such as Electron Beam CT (EBCT), single-slice CT und multi-detector row CT (MDCT) with 4, 16 and 64 simultaneously acquired slices. We identify the limitations of current CT-scanners, indicate potential of improvement and discuss alternative system concepts such as CT with area detectors and dual source CT (DSCT). PMID:18324372

  2. Epicardial adipose tissue: far more than a fat depot

    PubMed Central

    Talman, Andrew H.; Psaltis, Peter J.; Cameron, James D.; Meredith, Ian T.; Seneviratne, Sujith K.

    2014-01-01

    Epicardial adipose tissue (EAT) refers to the fat depot that exists on the surface of the myocardium and is contained entirely beneath the pericardium, thus surrounding and in direct contact with the major coronary arteries and their branches. EAT is a biologically active organ that may play a role in the association between obesity and coronary artery disease (CAD). Given recent advances in non-invasive imaging modalities such a multidetector computed tomography (MDCT), EAT can be accurately measured and quantified. In this review, we focus on the evidence suggesting a role for EAT as a quantifiable risk marker in CAD, as well as describe the role EAT may play in the development and vulnerability of coronary artery plaque. PMID:25610800

  3. Biliary tract cancers: SEOM clinical guidelines.

    PubMed

    Benavides, M; Antón, A; Gallego, J; Gómez, M A; Jiménez-Gordo, A; La Casta, A; Laquente, B; Macarulla, T; Rodríguez-Mowbray, J R; Maurel, J

    2015-12-01

    Biliary tract cancer (BTC) is an uncommon and highly fatal malignancy. It is composed of three main different entities; Gall bladder carcinoma (GBC), intrahepatic cholangiocarcinoma (iCC) and extrahepatic cholangiocarcinoma (eCC) sharing different genetic, risk factors and clinical presentation. Multidetector-row computed tomography (MDCT) and magnetic resonance cholangio-pancreatography (MRCP) are the more important diagnostic techniques. Surgery is the only potentially curative therapy but disease recurrence is frequent. Treatment with chemotherapy, radiotherapy or both has not demonstrated survival benefit in the adjuvant setting. Cisplatin plus gemcitabine constitutes the gold standard in metastatic disease. New ongoing studies mainly in the adjuvant and neoadjuvant setting along with molecular research will hopefully help to improve survival and quality of life of this disease. PMID:26607930

  4. Successful Parenchyma-Sparing Anatomical Surgery by 3-Dimensional Reconstruction of Hilar Cholangiocarcinoma Combined with Anatomic Variation.

    PubMed

    Ni, Qihong; Wang, Haolu; Liang, Xiaowen; Zhang, Yunhe; Chen, Wei; Wang, Jian

    2016-06-01

    The combination of hilar cholangiocarcinoma and anatomic variation constitutes a rare and complicated condition. Precise understanding of 3-dimensional position of tumor in the intrahepatic structure in such cases is important for operation planning and navigation. We report a case of a 61-year woman presenting with hilar cholangiocarcinoma. Anatomic variation and tumor location were well depicted on preoperative multidetector computed tomography (MDCT) combined with 3-dimensional reconstruction as the right posterior segmental duct drained to left hepatic duct. The common hepatic duct, biliary confluence, right anterior segmental duct, and right anterior branch of portal vein were involved by the tumor (Bismuth IIIa). After carefully operation planning, we successfully performed a radical parenchyma-sparing anatomical surgery of hilar cholangiocarcinoma: Liver segmentectomy (segments 5 and 8) and caudate lobectomy. MDCTcombined with 3-dimensional reconstruction is a reliable non-invasive modality for preoperative evaluation of hilar cholangiocarcinoma. PMID:27376205

  5. [Recommendations for radiological diagnosis and assessment of treatment response in lung cancer: a national consensus statement by the Spanish Society of Medical Radiology and the Spanish Society of Medical Oncology].

    PubMed

    Ferreirós, J; Cabeza, B; Gayete, Á; Sánchez, M; Torres, M I; Cobo, M; Isla, D; Puente, J; Reguart, N; de Castro, J

    2015-01-01

    The last decade has seen substantial progress in the diagnostic and therapeutic approach to lung cancer, thus meaning that its prognosis has improved. The Spanish Society of Medical Radiology (SERAM) and the Spanish Society of Medical Oncology (SEOM) have therefore produced a national consensus statement in order to make recommendations for radiological diagnosis and assessment of treatment response in patients with lung cancer. This expert group recommends multi-detector computed tomography (MDCT) as the technique of choice for investigating this disease. The radiology report should include a full assessment by the TNM staging system. Lastly, when the patient is on immunotherapy, response evaluation should employ not only Response Evaluation Criteria in Solid Tumours (RECIST 1.1) but also Immune-Related Response Criteria (irRC).

  6. High Intensity Focused Ultrasound Ablation of Pancreatic Neuroendocrine Tumours: Report of Two Cases

    SciTech Connect

    Orgera, Gianluigi; Krokidis, Miltiadis; Monfardini, Lorenzo; Bonomo, Guido; Della Vigna, Paolo; Fazio, Nicola; Orsi, Franco

    2011-04-15

    We describe the use of ultrasound-guided high-intensity focused ultrasound (HIFU) for ablation of two pancreatic neuroendocrine tumours (NETs; insulinomas) in two inoperable young female patients. Both suffered from episodes of severe nightly hypoglycemia that was not efficiently controlled by medical treatment. After HIFU ablation, local disease control and symptom relief were achieved without postinterventional complications. The patients remained free of symptoms during 9-month follow-up. The lesions appeared to be decreased in volume, and there was decreased enhancing pattern in the multidetector computed tomography control (MDCT). HIFU is likely to be a valid alternative for symptoms control in patients with pancreatic NETs. However, currently the procedure should be reserved for inoperable patients for whom symptoms cannot be controlled by medical therapy.

  7. Detecting double compression of audio signal

    NASA Astrophysics Data System (ADS)

    Yang, Rui; Shi, Yun Q.; Huang, Jiwu

    2010-01-01

    MP3 is the most popular audio format nowadays in our daily life, for example music downloaded from the Internet and file saved in the digital recorder are often in MP3 format. However, low bitrate MP3s are often transcoded to high bitrate since high bitrate ones are of high commercial value. Also audio recording in digital recorder can be doctored easily by pervasive audio editing software. This paper presents two methods for the detection of double MP3 compression. The methods are essential for finding out fake-quality MP3 and audio forensics. The proposed methods use support vector machine classifiers with feature vectors formed by the distributions of the first digits of the quantized MDCT (modified discrete cosine transform) coefficients. Extensive experiments demonstrate the effectiveness of the proposed methods. To the best of our knowledge, this piece of work is the first one to detect double compression of audio signal.

  8. [Review of pre- and post-treatment multidetector computed tomography findings in abdominal aortic aneurysms].

    PubMed

    Casula, E; Lonjedo, E; Cerverón, M J; Ruiz, A; Gómez, J

    2014-01-01

    The increase in the frequency of abdominal aortic aneurysms (AAA) and the widely accepted use of endovascular aneurysm repair (EVAR) as a first-line treatment or as an alternative to conventional surgery make it necessary for radiologists to have thorough knowledge of the pre- and post-treatment findings. The high image quality provided by multidetector computed tomography (MDCT) enables CT angiography to play a fundamental role in the study of AAA and in planning treatment. The objective of this article is to review the cases of AAA in which CT angiography was the main imaging technique, so that radiologists will be able to detect the signs related to this disease, to diagnose it, to plan treatment, and to detect complications in the postoperative period.

  9. On the Effects of Intra- and Inter-Subject Variabilities on Human Inspiratory Flow

    NASA Astrophysics Data System (ADS)

    Choi, Jiwoong; Lin, Ching-Long; Tawhai, Merryn H.; Hoffman, Eric A.

    2007-11-01

    The effects of intra- and inter-subject variabilities on airflow patterns in the human central airways are investigated using large-eddy simulation (LES). The anatomical airway models are reconstructed from multi-detector row computed tomography (MDCT) image data. The intra-subject study considers four models of the same human subject, including complete, partial, and no upper respiratory tract. Either pressure or velocity boundary conditions are specified at the mouth, mid pharynx, supraglottis, and tracheal entrance, respectively, with two different flow rates. The inter-subject study considers upper and intra-thoracic airways (up to 6 generations) of two human subjects. LES captures the turbulent laryngeal jet formed at the vocal cords. It is found that the use of a complete upper respiratory tract as well as the anatomically realistic airway geometry is essential to correctly reproduce the laryngeal jet behavior and turbulent coherent structures in particular.

  10. Evaluation of renal vascular anatomy in live renal donors: Role of multi detector computed tomography

    PubMed Central

    Pandya, Vaidehi Kumudchandra; Patel, Alpeshkumar Shakerlal; Sutariya, Harsh Chandrakant; Gandhi, Shruti Pradipkumar

    2016-01-01

    Background: Evaluation of renal vascular variations is important in renal donors to avoid vascular complications during surgery. Venous variations, mainly resulting from the errors of the embryological development, are frequently observed. Aim: This retrospective cross-sectional study aimed to investigate the renal vascular variants with multidetector computed tomography (MDCT) angiography to provide valuable information for surgery and its correlations with surgical findings. Materials and Methods: A total of 200 patients underwent MDCT angiography as a routine work up for live renal donors. The number, course, and drainage patterns of the renal veins were retrospectively observed from the scans. Anomalies of renal veins and inferior vena cava (IVC) were recorded and classified. Multiplanar reformations (MPRs), maximum intensity projections, and volume rendering were used for analysis. The results obtained were correlated surgically. Results: In the present study, out of 200 healthy donors, the standard pattern of drainage of renal veins was observed in only 67% of donors on the right side and 92% of donors on the left side. Supernumerary renal veins in the form of dual and triple renal veins were seen on the right side in about 32.5% of donors (dual right renal veins in 30.5% cases and triple right renal veins in 2.5% cases). Variations on the left side were classified into four groups: supernumerary, retro-aortic, circumaortic, and plexiform left renal veins in 1%, 2.5%, 4%, 0.5%, cases respectively. Conclusions: Developmental variations in renal veins can be easily detected on computed tomography scan, which can go unnoticed and can pose a fatal threat during major surgeries such as donor nephrectomies in otherwise healthy donors if undiagnosed. PMID:27453646

  11. Preoperative staging of colorectal cancer: CT vs. integrated FDG PET/CT.

    PubMed

    Shin, Sang Soo; Jeong, Yong Yeon; Min, Jung Jun; Kim, Hyeong Rok; Chung, Tae Woong; Kang, Heoung Keun

    2008-01-01

    Accurate preoperative staging is essential in determining the optimal therapeutic planning for individual patients. The computed tomography (CT) in the preoperative staging of colorectal cancer, even if controversial, may be useful for planning surgery and/or neoadjuvant therapy, particularly when local tumor extension into adjacent organs or distant metastases are detected. There have been significant changes in the CT technology with the advent of multi-detector row CT (MDCT) scanner. Advances in CT technology have raised interest in the potential role of CT for detection and staging of colorectal cancer. In recent studies, MDCT with MPR images has shown promising accuracy in the evaluation of local extent and nodal involvement of colorectal cancer. Combined PET/CT images have significant advantages over either alone because it provides both functional and anatomical data. Therefore, it is natural to expect that PET/CT would improve the accuracy of preoperative staging of colorectal cancer. The most significant additional information provided by PET/CT relates to the accurate detection of distant metastases. For the evaluation of patients with colorectal cancer, CT has relative advantages over PET/CT in regard to the depth of tumor invasion through the wall, extramural extension, and regional lymph node metastases. PET/CT should be performed on selected patients with suggestive but inconclusive metastatic lesions with CT. In addition, PET/CT with dedicated CT protocols, such as contrast-enhanced PET/CT and PET/CT colonography, may replace the diagnostic CT for the preoperative staging of colorectal cancer.

  12. Computational Method for Identifying and Quantifying Shape Features of Human Left Ventricular Remodeling

    PubMed Central

    Ardekani, Siamak; Weiss, Robert G.; Lardo, Albert C.; George, Richard T.; Lima, Joao A. C.; Wu, Katherine C.; Miller, Michael I.; Winslow, Raimond L.; Younes, Laurent

    2010-01-01

    Left ventricular remodeling during the development of heart failure is a strong predictor of cardiovascular mortality. However, methods to objectively quantify remodeling-associated shape changes are not routinely available but may be possible with new computational anatomy tools. In this study, we analyzed and compared multi-detector computed tomographic (MDCT) images of ventricular shape at endsystole (ES) and end-diastole (ED) to determine whether regional structural characteristics could be identified and, as a proof of principle, whether differences in hearts of patients with anterior myocardial infarction (MI) and ischemic cardiomyopathy (ICM) could be distinguished from those with global nonischemic cardiomyopathy (NICM). MDCT images of hearts from 11 patients (5 with ICM) with ejection fractions (EF) > 35% were analyzed. An average ventricular shape model (template) was constructed for each cardiac phase by bringing heart shapes into correspondence using linear and nonlinear image matching algorithms. Next, transformation fields were computed between the template image and individual heart images in the population. Principal component analysis (PCA) method was used to quantify ventricular shape differences described by the transformation vector fields. Statistical analysis of PCA coefficients revealed significant ventricular shape differences at ED (p = 0.03) and ES (p = 0.03). For validation, a second set of 14 EF-matched patients (8 with ICM) were evaluated. The discrimination rule learned from the training data set was able to differentiate ICM from NICM patients (p = 0.008). Application of a novel shape analysis method to in vivo human cardiac images acquired on a clinical scanner is feasible and can quantify regional shape differences at end-systole in remodeled myopathic human myocardium. This approach may be useful in identifying differences in the remodeling process between ICM and NICM populations and possibly in differentiating the populations

  13. Analysis of trabecular distribution of the proximal femur in patients with fragility fractures

    PubMed Central

    2013-01-01

    Background Multi-detector computed tomography (MDCT) was used in order to assess the trabecular distribution of proximal femur and its relationship with hip fragility fractures. Methods A total of 99 elderly women were scanned by MDCT including: 27 trochanteric hip fractures (group A), 40 femoral neck fractures (group B), and 32 non-fractures (group C). A mid-coronal MPR image of the proximal femur was reconstructed for every patient by e-Film95 software. Four regions of interest (ROI) were chosen in the images including compressive trabecula (ComT), tensile trabecula (TenT), trochanteric trabecula (TroT) and Ward's triangle (WT) region. The mean CT values were measured by the software. Results The mean age was 81.44, 74.10 and 69.25 years for groups A, B and C, respectively. There was significant inter-group differences based on one-way ANOVA (P<0.05). The CT values in the four ROIs had significant differences in the groups except for TenT between group A and B (P>0.05). After the age adjustment with ANCOVA, the mean CT values of TroT and WT were significantly lower in group A as compared to that of the group B (P<0.05). However, there were no significant differences for ComT and TenT between groups A and B (P>0.05). Conclusions The occurrence of femoral neck fracture was closely related to the degeneration of ComT and TenT. Trochanteric hip fractures were associated with a more severe degeneration in TroT as well as an enlargement of WT region besides the ComT and TenT degeneration. We concluded that the hip fragility fractures might be predicted by the measurement of the mean CT values in ComT, TenT, TroT and WT region. PMID:23570243

  14. Multi-Detector Computed Tomography in Evaluating Locally Aggressive and Malignant Bone Tumours

    PubMed Central

    Ramavathu, Kumar Venu Madhav; Garga, U.C.

    2015-01-01

    Objective: To evaluate the ability of Multi-Detector Computed Tomography in preoperative evaluation of locally aggressive and malignant bone tumours in correlation with histopathological findings. Materials and Methods: Twenty patients suspected of malignant bone tumours on the basis of their clinical profile were selected. Following a plain radiograph evaluation, all of them were subjected to CT scan examination. Multi Planar Reconstruction (MPR) was done in sagittal and coronal planes and also three-dimensional Volume Rendering (VR) and Maximum Intensity Projection (MIP) images were obtained. Results: Of the 20 patients, 18 underwent surgery, and their histopathological findings were compared and correlated with MDCT findings. MDCT was 92.8% sensitive and 100% specific in determining the vascularity of the tumour and also can detect displacement/ encasement/ involvement of adjacent vessels. It has a sensitivity and specificity of 100% in determining cortical break, calcification and periosteal reaction. However, it is less sensitive in detecting joint involvement. Post contrast enhancement gives details of the extent of the soft tissue component. Conclusion: Although MRI is a preferred modality in preoperative evaluation of bone tumours, CT may be used an alternative in case of non-availability of MRI, which has faster acquisition time and better resolution. Using three dimensional MPR imaging, the location and extent of the tumour can be studied. It is also useful in determining cortical discontinuity, periosteal reaction, and calcification. By virtue of MIP and VR imaging, vascularity of the tumour and its relationship with the adjacent vasculature can be established. However, it is inferior to MRI in soft tissue characterization and has poor sensitivity in detecting marrow and joint involvement. PMID:26023618

  15. Experimental Model of Tuberculosis in the Domestic Goat after Endobronchial Infection with Mycobacterium caprae ▿

    PubMed Central

    Pérez de Val, Bernat; López-Soria, Sergio; Nofrarías, Miquel; Martín, Maite; Vordermeier, H. Martin; Villarreal-Ramos, Bernardo; Romera, Nadine; Escobar, Manel; Solanes, David; Cardona, Pere-Joan; Domingo, Mariano

    2011-01-01

    Caprine tuberculosis (TB) has increased in recent years, highlighting the need to address the problem the infection poses in goats. Moreover, goats may represent a cheaper alternative for testing of prototype vaccines in large ruminants and humans. With this aim, a Mycobacterium caprae infection model has been developed in goats. Eleven 6-month-old goats were infected by the endobronchial route with 1.5 × 103 CFU, and two other goats were kept as noninfected controls. The animals were monitored for clinical and immunological parameters throughout the experiment. After 14 weeks, the goats were euthanized, and detailed postmortem analysis of lung lesions was performed by multidetector computed tomography (MDCT) and direct observation. The respiratory lymph nodes were also evaluated and cultured for bacteriological analysis. All infected animals were positive in a single intradermal comparative cervical tuberculin (SICCT) test at 12 weeks postinfection (p.i.). Gamma interferon (IFN-γ) antigen-specific responses were detected from 4 weeks p.i. until the end of the experiment. The humoral response to MPB83 was especially strong at 14 weeks p.i. (13 days after SICCT boost). All infected animals presented severe TB lesions in the lungs and associated lymph nodes. M. caprae was recovered from pulmonary lymph nodes in all inoculated goats. MDCT allowed a precise quantitative measure of TB lesions. Lesions in goats induced by M. caprae appeared to be more severe than those induced in cattle by M. bovis over a similar period of time. The present work proposes a reliable new experimental animal model for a better understanding of caprine tuberculosis and future development of vaccine trials in this and other species. PMID:21880849

  16. When gas analysis assists with postmortem imaging to diagnose causes of death.

    PubMed

    Varlet, V; Smith, F; Giuliani, N; Egger, C; Rinaldi, A; Dominguez, A; Chevallier, C; Bruguier, C; Augsburger, M; Mangin, P; Grabherr, S

    2015-06-01

    Postmortem imaging consists in the non-invasive examination of bodies using medical imaging techniques. However, gas volume quantification and the interpretation of the gas collection results from cadavers remain difficult. We used whole-body postmortem multi-detector computed tomography (MDCT) followed by a full autopsy or external examination to detect the gaseous volumes in bodies. Gases were sampled from cardiac cavities, and the sample compositions were analyzed by headspace gas chromatography-mass spectrometry/thermal conductivity detection (HS-GC-MS/TCD). Three categories were defined according to the presumed origin of the gas: alteration/putrefaction, high-magnitude vital gas embolism (e.g., from scuba diving accident) and gas embolism of lower magnitude (e.g., following a traumatic injury). Cadaveric alteration gas was diagnosed even if only one gas from among hydrogen, hydrogen sulfide or methane was detected. In alteration cases, the carbon dioxide/nitrogen ratio was often >0.2, except in the case of advanced alteration, when methane presence was the best indicator. In the gas embolism cases (vital or not), hydrogen, hydrogen sulfide and methane were absent. Moreover, with high-magnitude vital gas embolisms, carbon dioxide content was >20%, and the carbon dioxide/nitrogen ratio was >0.2. With gas embolisms of lower magnitude (gas presence consecutive to a traumatic injury), carbon dioxide content was <20% and the carbon dioxide/nitrogen ratio was often <0.2. We found that gas analysis provided useful assistance to the postmortem imaging diagnosis of causes of death. Based on the quantifications of gaseous cardiac samples, reliable indicators were determined to document causes of death. MDCT examination of the body must be performed as quickly as possible, as does gas sampling, to avoid generating any artifactual alteration gases. Because of cardiac gas composition analysis, it is possible to distinguish alteration gases and gas embolisms of different

  17. An hybrid CPU-GPU framework for quantitative follow-up of abdominal aortic aneurysm volume by CT angiography

    NASA Astrophysics Data System (ADS)

    Kauffmann, Claude; Tang, An; Therasse, Eric; Soulez, Gilles

    2010-03-01

    We developed a hybrid CPU-GPU framework enabling semi-automated segmentation of abdominal aortic aneurysm (AAA) on Computed Tomography Angiography (CTA) examinations. AAA maximal diameter (D-max) and volume measurements and their progression between 2 examinations can be generated by this software improving patient followup. In order to improve the workflow efficiency some segmentation tasks were implemented and executed on the graphics processing unit (GPU). A GPU based algorithm is used to automatically segment the lumen of the aneurysm within short computing time. In a second step, the user interacted with the software to validate the boundaries of the intra-luminal thrombus (ILT) on GPU-based curved image reformation. Automatic computation of D-max and volume were performed on the 3D AAA model. Clinical validation was conducted on 34 patients having 2 consecutive MDCT examinations within a minimum interval of 6 months. The AAA segmentation was performed twice by a experienced radiologist (reference standard) and once by 3 unsupervised technologists on all 68 MDCT. The ICC for intra-observer reproducibility was 0.992 (>=0.987) for D-max and 0.998 (>=0.994) for volume measurement. The ICC for inter-observer reproducibility was 0.985 (0.977-0.90) for D-max and 0.998 (0.996- 0.999) for volume measurement. Semi-automated AAA segmentation for volume follow-up was more than twice as sensitive than D-max follow-up, while providing an equivalent reproducibility.

  18. Stature estimation in Japanese cadavers using the sacral and coccygeal length measured with multidetector computed tomography.

    PubMed

    Torimitsu, Suguru; Makino, Yohsuke; Saitoh, Hisako; Ishii, Namiko; Hayakawa, Mutsumi; Yajima, Daisuke; Inokuchi, Go; Motomura, Ayumi; Chiba, Fumiko; Iwase, Hirotaro

    2014-01-01

    We evaluated the relationship between stature and the length of the sacrum and coccyx using multidetector computed tomography (MDCT) and derived regression equations for stature estimation in the modern Japanese population. Two hundred and sixteen Japanese subjects (110 males and 106 females) who underwent postmortem computed tomography with subsequent forensic autopsy between January 2010 and August 2013 were measured. A sagittal-plane image of the sacrum and coccyx was used. Anterior sacral length (ASL) was defined as the linear distance from the anterosuperior edge of the first sacral vertebra (S1) to the anteroinferior edge of the fifth sacral vertebra (S5), and posterior sacral length (PSL) was defined as the linear distance from the posterosuperior edge of S1 to the anteroinferior edge of S5. Anterior sacrococcygeal length (ASCL) was defined as the linear distance from the anterosuperior edge of S1 to the anteroinferior edge of the last coccygeal vertebra (LCV), and posterior sacrococcygeal length (PSCL) was defined as the linear distance from the posterosuperior edge of S1 to the anteroinferior edge of the LCV. The correlation between stature and each parameter was evaluated by simple regression analysis using Pearson product-moment correlation coefficients. Each parameter was significantly and positively correlated with stature among both males and females. Cadaver stature (CS, cm)=0.39×PSL (mm)+123.70 [Corrected] provided the most accurate stature prediction (R=0.507, SEE=5.83 cm) in males. CS (cm)=0.56×PSCL (mm)+85.29 provided the most accurate stature prediction (R=0.659, SEE=6.68 cm) in females. We conclude that sacral/sacrococcygeal length measured with MDCT is a potentially useful tool for stature estimation, particularly in cases where better predictors such as the long bones are not available.

  19. Influence of pulmonary emphysema on COPD assessment test-oriented categorization in GOLD document

    PubMed Central

    Suzuki, Toshio; Tada, Yuji; Kawata, Naoko; Ikari, Jun; Kasahara, Yasunori; Sakurai, Yoriko; Iesato, Ken; Nishimura, Rintaro; West, James; Tatsumi, Koichiro

    2015-01-01

    Background The COPD assessment test (CAT) score is a key component of the multifactorial assessment of COPD in the Global initiative for chronic Obstructive Lung Disease (GOLD) guidelines of 2014. Nevertheless, little is known regarding the differences among COPD categories in terms of clinical parameters such as pulmonary function or radiological findings. Thus, our aims in this study were to evaluate the associations between CAT scores and pulmonary clinical parameters, and to investigate factors that could discriminate between a “less symptomatic group” (categories A and C) and a “more symptomatic group” (categories B and D) among stable COPD patients. Methods We enrolled 200 outpatients at Chiba University Hospital. Study subjects were assessed by CAT, pulmonary function testing, and multidetector computed tomography (MDCT). We assessed possible correlations between these indices. Results CAT scores were negatively correlated with percentage of the forced expiratory volume in 1 second predicted value (FEV1 %predicted) and percentage of the diffusing capacity for carbon monoxide per liter of lung volume predicted value (DLCO/VA [%predicted]) results and positively correlated with low attenuation volume percentage (LAV%) and residual volume to total lung capacity ratios (RV/TLC). In the “more symptomatic group” (category B or D), the mean DLCO/VA (%predicted) was significantly lower and the mean LAV% and RV/TLC was significantly higher than those in the “less symptomatic group” (category A or C), respectively. Interestingly, those in category B had higher mean LAV% compared to those in category C. Conclusion CAT scores were significantly correlated with pulmonary function parameters and emphysematous changes on MDCT. The new GOLD classification system would be a step toward a phenotypic approach, especially taking into account the degree of emphysema and hyperinflation. PMID:26150711

  20. Comparison of methods for assessing geometric efficiency on multi-detector CT scanners.

    PubMed

    Berris, Theocharis; Perisinakis, Kostas; Papadakis, Antonios E; Damilakis, John

    2013-05-01

    The aim of the current study was to compare the film method against the method based on a new CT slice detector in assessing geometric efficiency (GE) of x-ray beams utilized by a multi-detector CT (MDCT) scanner. Measurements of GE were performed using radiographic films and a solid state CT slice detector for all beam qualities, collimations and focal spot sizes available on an MDCT scanner. Repeatability of GE measurements was assessed. The radiographic film and the solid state detector methods were compared to each other in regard to efficacy in measuring free-in-air GE. The values of GE determined using the radiographic film method were found to range between 48.5% and 90.6%. Differences between values obtained with the radiographic film method and corresponding values obtained with the solid state detector were less than 10% exceeding 5% for only one case. Both methods show that wide beams have higher GE values compared to thin ones. The use of large instead of small focal spot was found to deteriorate GE values by up to 23.1%. Beam quality did not seem to influence GE of the various collimations. When thin beam collimations are employed, a considerable amount of the radiation is wasted for non-imaging purposes. Both film and solid state probe methods are capable of measuring GE of thin as well as wide collimations. The solid state detector is the easiest to use, however its usefulness is reduced by the fact that it cannot measure dose profiles of beam collimations available for step-and-shoot mode of operation.

  1. Prediction of Intimal Tear Site by Computed Tomography in Acute Aortic Dissection Type A

    PubMed Central

    Kim, Jun Sung; Lim, Cheong; Kim, Dong Jin; Jung, Yochun; Shin, Yoon Cheol; Choi, Sang Il; Chun, Eun Ju; Yoo, Jin Young

    2016-01-01

    Background and Objectives Preoperative identification of intimal tear site in acute type A dissection will help procedural planning. The objective of this study was to determine the key findings of computed tomography (CT)-based prediction for tear site and compare the accuracy between radiologists and surgeons. Subjects and Methods Multi-detector CT (MDCT) images from 50 patients who underwent surgical repair of type A aortic dissection were retrospectively reviewed by 4 cardiac surgeons with limited experience or by 3 radiologists specialized in cardiovascular imaging. Surgical findings of intimal tear site were used as references. Results In surgical findings, the locations of intimal tear that were identified in 43 patients included aorta (n=25), ascending with arch (n=7), and arch only (n=11). The rest were retrograde dissections from the tear of descending aorta. Key CT findings that were most frequently found were defect in the intimal flap shadow (30.0±4.0 patients/reviewer, accuracy 87.0±11.7%) and differential filling of false lumen by phase and location (9.4±2.9 patients/reviewer, 84.8±10.4%). Surgeons predicted tear site (75.0±7.7% vs. 86.7±1.2%, p=0.055) and specified flap defect (80.5±10.3% vs. 95.7±7.4%, p=0.073) with lower accuracy than radiologists. Conclusions With MDCT imaging, well-educated surgeons could be accurate in three fourths of cases. There was room for improvement through experience. Considering the substantial possibility of inaccuracy, critical decisions on CT images should be made through thorough reviewing by as many experienced radiologists and surgeons as possible. PMID:26798385

  2. SU-E-I-28: Introduction and Investigation of Effective Diameter Ratios as a New Patient Size Metric for Use in CT

    SciTech Connect

    Lamoureux, R; Sinclair, L; Mench, A; Lipnharski, I; Carranza, C; Bidari, S; Cormack, B; Rill, L; Arreola, M

    2015-06-15

    Purpose: To introduce and investigate effective diameter ratios as a new patient metric for use in computed tomography protocol selection as a supplement to patient-specific size parameter data. Methods: The metrics of outer effective diameter and inner effective diameter were measured for 7 post-mortem subjects scanned with a standardized chest/abdomen/pelvis (CAP) protocol on a 320-slice MDCT scanner. The outer effective diameter was calculated by obtaining the anterior/posterior and lateral dimensions of the imaged anatomy at the middle of the scan range using Effective Diameter= SQRT(AP height*Lat Width). The inner effective diameter was calculated with the same equation using the AP and Lat dimensions of the anatomy excluding the adipose tissue. The ratio of outer to inner effective diameter was calculated for each subject. A relationship to BMI, weight, and CTDI conversion coefficients was investigated. Results: For the largest subject with BMI of 43.85 kg/m2 and weight of 255 lbs the diameter ratio was calculated as 1.33. For the second largest subject with BMI of 33.5 kg/m2 and weight of 192.4 lbs the diameter ratio was measured as 1.43, indicating a larger percentage of adipose tissue in the second largest subject’s anatomical composition. For the smallest subject at BMI of 17.4 kg/m2 and weight of 86 lbs a similar tissue composition was indicated as a subject with BMI of 24.2 kg/m2 and weight of 136 lbs as they had the same diameter ratios of 1.11. Conclusion: The diameter ratio proves to contain information about anatomical composition that the BMI and weight alone do not. The utility of this metric is still being examined but could prove useful for determining MDCT techniques and for giving a more in depth detail of the composition of a patient’s body habitus.

  3. A study of the short- to long-phantom dose ratios for CT scanning without table translation

    SciTech Connect

    Li, Xinhua; Zhang, Da; Liu, Bob; Yang, Jie

    2014-09-15

    Purpose: For CT scanning in the stationary-table modes, AAPM Task Group 111 proposed to measure the midpoint dose on the central and peripheral axes of sufficiently long phantoms. Currently, a long cylindrical phantom is usually not available in many clinical facilities. The use of a long phantom is also challenging because of the heavy weight. In order to shed light on assessing the midpoint dose in CT scanning without table movement, the authors present a study of the short- to long-phantom dose ratios, and perform a cross-comparison of CT dose ratios on different scanner models. Methods: The authors performed Geant4-based Monte Carlo simulations with a clinical CT scanner (Somatom Definition dual source CT, Siemens Healthcare), and modeled dosimetry measurements using a 0.6 cm{sup 3} Farmer type chamber and a 10-cm long pencil ion chamber. The short (15 cm) to long (90 cm) phantom dose ratios were computed for two PMMA diameters (16 and 32 cm), two phantom axes (the center and the periphery), and a range of beam apertures (3–25 cm). The results were compared with the published data of previous studies with other multiple detector CT (MDCT) scanners and cone beam CT (CBCT) scanners. Results: The short- to long-phantom dose ratios changed with beam apertures but were insensitive to beam qualities (80–140 kV, the head and body bowtie filters) and MDCT and CBCT scanner models. Conclusions: The short- to long-phantom dose ratios enable medical physicists to make dosimetry measurements using the standard CT dosimetry phantoms and a Farmer chamber or a 10 cm long pencil chamber, and to assess the midpoint dose in long phantoms. This method provides an effective approach for the dosimetry of CBCT scanning in the stationary-table modes, and is useful for perfusion and interventional CT.

  4. Evaluation of postoperative lymphocele according to amounts and symptoms by using 3-dimensional CT volumetry in kidney transplant recipients

    PubMed Central

    Jun, Heungman; Hwang, Sung Ho; Lim, Sungyoon; Kim, Myung Gyu

    2016-01-01

    Purpose To analyze the risk factors for postoperative lymphocele, for predicting and preventing complications. Methods We evaluated 92 kidney transplant recipients with multidetector CT (MDCT) at 1-month posttransplantation. From admission and 1-month postoperative records, data including diabetes, dialysis type, immunosuppressant use, steroid pulse therapy, and transplantation side were collected. Lymphocele volume was measured with 3-dimensional reconstructed, nonenhanced MDCT at one month postoperatively. The correlations between risk factors and lymphocele volume and between risk factors and symptomatic lymphocele (SyL) were analyzed. The cutoff was calculated by using the receiver operating characteristic (ROC) curve for SyL volume. Results Among 92 recipients, the mean volume was 44.53 ± 176.43 cm3 and 12 had SyL. Univariable analysis between risk factors and lymphocele volume indicated that donor age, retransplantation, and inferiorly located lymphocele were statistically significant. The ROC curve for SyL showed that 33.20 cm3 was the cutoff, with 83.3% sensitivity and 93.7% specificity. On univariable analysis between risk factors and SyL, steroid pulse, inferiorly located lymphocele, and >33.20 cm3 were statistically significant. Multivariable analysis indicated that steroid pulse, >33.20 cm3, and serum creatinine level at one month were significant factors. Conclusion Risk factors including donor age, retransplantation, steroid pulse therapy, and inferiorly located lymphocele are important predictors of large lymphoceles or SyL. In high-risk recipients, careful monitoring of renal function and early image surveillance such as CT or ultrasound are recommended. If the asymptomatic lymphocele is >33.20 cm3 or located inferiorly, early interventions can be considered while carefully observing the changes in symptoms. PMID:27617254

  5. Tube focal spot size and power capability impact image quality in the evaluation of intracoronary stents

    NASA Astrophysics Data System (ADS)

    Cesmeli, Erdogan; Berry, Joel L.; Carr, J. J.

    2005-04-01

    Proliferation of coronary stent deployment for treatment of coronary heart disease (CHD) creates a need for imaging-based follow-up examinations to assess patency. Technological improvements in multi-detector computer tomography (MDCT) make it a potential non-invasive alternative to coronary catheterization for evaluation of stent patency; however, image quality with MDCT varies based on the size and composition of the stent. We studied the role of tube focal spot size and power in the optimization of image quality in a stationary phantom. A standard uniform physical phantom with a tubular insert was used where coronary stents (4 mm in diameter) were deployed in a tube filled with contrast to simulate a typical imaging condition observed in clinical practice. We utilized different commercially available stents and scanned them with different tube voltage and current settings (LightSpeed Pro16, GE Healthcare Technologies, Waukesha, WI, USA). The scanner used different focal spot size depending on the power load and thus allowed us to assess the combined effect of the focal spot size and the power. A radiologist evaluated the resulting images in terms of image quality and artifacts. For all stents, we found that the small focal spot size yielded better image quality and reduced artifacts. In general, higher power capability for the given focal spot size improved the signal-to-noise ratio in the images allowing improved assessment. Our preliminary study in a non-moving phantom suggests that a CT scanner that can deliver the same power on a small focal spot size is better suited to have an optimized scan protocol for reliable stent assessment.

  6. When gas analysis assists with postmortem imaging to diagnose causes of death.

    PubMed

    Varlet, V; Smith, F; Giuliani, N; Egger, C; Rinaldi, A; Dominguez, A; Chevallier, C; Bruguier, C; Augsburger, M; Mangin, P; Grabherr, S

    2015-06-01

    Postmortem imaging consists in the non-invasive examination of bodies using medical imaging techniques. However, gas volume quantification and the interpretation of the gas collection results from cadavers remain difficult. We used whole-body postmortem multi-detector computed tomography (MDCT) followed by a full autopsy or external examination to detect the gaseous volumes in bodies. Gases were sampled from cardiac cavities, and the sample compositions were analyzed by headspace gas chromatography-mass spectrometry/thermal conductivity detection (HS-GC-MS/TCD). Three categories were defined according to the presumed origin of the gas: alteration/putrefaction, high-magnitude vital gas embolism (e.g., from scuba diving accident) and gas embolism of lower magnitude (e.g., following a traumatic injury). Cadaveric alteration gas was diagnosed even if only one gas from among hydrogen, hydrogen sulfide or methane was detected. In alteration cases, the carbon dioxide/nitrogen ratio was often >0.2, except in the case of advanced alteration, when methane presence was the best indicator. In the gas embolism cases (vital or not), hydrogen, hydrogen sulfide and methane were absent. Moreover, with high-magnitude vital gas embolisms, carbon dioxide content was >20%, and the carbon dioxide/nitrogen ratio was >0.2. With gas embolisms of lower magnitude (gas presence consecutive to a traumatic injury), carbon dioxide content was <20% and the carbon dioxide/nitrogen ratio was often <0.2. We found that gas analysis provided useful assistance to the postmortem imaging diagnosis of causes of death. Based on the quantifications of gaseous cardiac samples, reliable indicators were determined to document causes of death. MDCT examination of the body must be performed as quickly as possible, as does gas sampling, to avoid generating any artifactual alteration gases. Because of cardiac gas composition analysis, it is possible to distinguish alteration gases and gas embolisms of different

  7. Prognostic impact of coronary microcirculation abnormalities in systemic sclerosis: a prospective study to evaluate the role of non-invasive tests

    PubMed Central

    2013-01-01

    Introduction Microcirculation dysfunction is a typical feature of systemic sclerosis (SSc) and represents the earliest abnormality of primary myocardial involvement. We assessed coronary microcirculation status by combining two functional tests in SSc patients and estimating its impact on disease outcome. Methods Forty-one SSc patients, asymptomatic for coronary artery disease, were tested for coronary flow velocity reserve (CFR) by transthoracic-echo-Doppler with adenosine infusion (A-TTE) and for left ventricular wall motion abnormalities (WMA) by dobutamine stress echocardiography (DSE). Myocardial multi-detector computed tomography (MDCT) enabled the presence of epicardial stenosis, which could interfere with the accuracy of the tests, to be excluded. Patient survival rate was assessed over a 6.7- ± 3.5-year follow-up. Results Nineteen out of 41 (46%) SSc patients had a reduced CFR (≤2.5) and in 16/41 (39%) a WMA was observed during DSE. Furthermore, 13/41 (32%) patients showed pathological CFR and WMA. An inverse correlation between wall motion score index (WMSI) during DSE and CFR value (r = -0.57, P <0.0001) was observed; in addition, CFR was significantly reduced (2.21 ± 0.38) in patients with WMA as compared to those without (2.94 ± 0.60) (P <0.0001). In 12 patients with abnormal DSE, MDCT was used to exclude macrovasculopathy. During a 6.7- ± 3.5-year follow-up seven patients with abnormal coronary functional tests died of disease-related causes, compared to only one patient with normal tests. Conclusions A-TTE and DSE tests are useful tools to detect non-invasively pre-clinical microcirculation abnormalities in SSc patients; moreover, abnormal CFR and WMA might be related to a worse disease outcome suggesting a prognostic value of these tests, similar to other myocardial diseases. PMID:23302110

  8. Comparison of the Using Ability Between a Smartphone and a Conventional Mobile Phone in People With Cervical Cord Injury

    PubMed Central

    Kim, Seongkyu; Kim, Ji Min

    2014-01-01

    Objective To investigate the ability of spinal cord injury (SCI) patients in the use mobile cellular devices, especially the smartphone. Methods Seventeen people with motor complete cervical SCI participated in the study. The assist-devices deemed most fitting were introduced to the patients: a mouth stick, multifunctional splint, activities of daily living (ADL) splint, universal cuff or none of the above. To determine the effective devices, a Multi-Directional Click Test (MDCT), Phone Number Test (PNT), and individual satisfaction inquiry were used. The most appropriate assist device was selected by MDCT. Subsequently PNT and individual satisfaction inquiry were performed with the conventional model and compared. Results Those with C4 cord injury chose mouth stick. Those with C5 cord injury chose multifunctional splint (3 people) and ADL splint (2 people). Those with C6 cord injury chose universal cuff (3 people) or bare hands only. Those with C7 cord injury chose universal cuff (3 people). With a smartphone, all participants were able to complete the PNT. With a conventional model, only twelve participants (71%) were able to complete the same test. While it took 26.8±6.8 seconds with a conventional model to complete PNT, the same test took 18.8±10.9 seconds to complete with a smartphone (p<0.05). Overall, participants expressed higher satisfaction when using a smartphone. Conclusion The results offer a practical insight into the appropriate assist devices for SCI patients who wish to use mobile cellular devices, particularly smartphones. When the SCI patients are given the use of a smartphone with the appropriate assist devices, the SCI patients are expected to access mobile cellular device faster and with more satisfaction. PMID:24855612

  9. CFD MODELING ANALYSIS OF MECHANICAL DRAFT COOLING TOWER

    SciTech Connect

    Lee, S; Alfred Garrett, A; James02 Bollinger, J; Larry Koffman, L

    2008-03-03

    Industrial processes use mechanical draft cooling towers (MDCT's) to dissipate waste heat by transferring heat from water to air via evaporative cooling, which causes air humidification. The Savannah River Site (SRS) has a MDCT consisting of four independent compartments called cells. Each cell has its own fan to help maximize heat transfer between ambient air and circulated water. The primary objective of the work is to conduct a parametric study for cooling tower performance under different fan speeds and ambient air conditions. The Savannah River National Laboratory (SRNL) developed a computational fluid dynamics (CFD) model to achieve the objective. The model uses three-dimensional steady-state momentum, continuity equations, air-vapor species balance equation, and two-equation turbulence as the basic governing equations. It was assumed that vapor phase is always transported by the continuous air phase with no slip velocity. In this case, water droplet component was considered as discrete phase for the interfacial heat and mass transfer via Lagrangian approach. Thus, the air-vapor mixture model with discrete water droplet phase is used for the analysis. A series of the modeling calculations was performed to investigate the impact of ambient and operating conditions on the thermal performance of the cooling tower when fans were operating and when they were turned off. The model was benchmarked against the literature data and the SRS test results for key parameters such as air temperature and humidity at the tower exit and water temperature for given ambient conditions. Detailed results will be presented here.

  10. Relationships between the pulmonary densitometry values obtained by CT and the forced oscillation technique parameters in patients with silicosis

    PubMed Central

    Mogami, R; Camilo, G B; Machado, D C; Melo, P L; Carvalho, A R S

    2015-01-01

    Objective: To evaluate the correlations between pulmonary densitometry values and forced oscillation technique (FOT) parameters in patients with silicosis. Methods: This cross-sectional study comprised 36 non-smoker patients with silicosis and 20 matched control subjects who were submitted to FOT and multidetector CT (MDCT). Results: Compared with the control subjects, the MDCT evaluation demonstrated that patients with silicosis exhibited greater total lung mass. These patients also had larger non-aerated and poorly aerated compartments, which included nodules and scarring. Compared with the control subjects, FOT evaluation demonstrated that patients with silicosis exhibited changes in both reactive and resistive properties of the respiratory system. In these patients, there was a greater heterogeneity of the respiratory system and increased work of breathing. Significant correlations between non-aerated compartment size and FOT parameters that reflect the non-homogeneity of the respiratory system were observed. The dynamic compliance of the respiratory system was negatively correlated with non-aerated compartment size, while the impedance at 4 Hz was positively correlated with non-aerated compartment size. Conclusion: Patients with silicosis have heavier lungs. In these patients, a larger non-aerated compartment is associated with a worsening of lung function. A more significant pulmonary involvement is associated with a loss of homogeneity and increased mechanical load of the respiratory system. Advances in knowledge The findings provided by both pulmonary densitometry and FOT may add valuable information to the subjective analysis of silicosis; however, more studies are necessary to evaluate the potential use of these methods for assessing disease progression. PMID:25747897

  11. Reproducibility of coronary atherosclerotic plaque characteristics in populations with low, intermediate, and high prevalence of coronary artery disease by multidetector computer tomography: a guide to reliable visual coronary plaque assessments.

    PubMed

    de Knegt, Martina C; Linde, Jesper J; Fuchs, Andreas; Nordestgaard, Børge G; Køber, Lars V; Hove, Jens D; Kofoed, Klaus F

    2016-10-01

    To evaluate the interobserver agreement of visual coronary plaque characteristics by 320-slice multidetector computed tomography (MDCT) in three populations with low, intermediate and high CAD prevalence and to identify determinants for the reproducible assessment of these plaque characteristics. 150 patients, 50 asymptomatic subjects from the general population (low CAD prevalence), 50 symptomatic non-acute coronary syndrome (non-ACS) patients (intermediate CAD prevalence), and 50 ACS patients (high CAD prevalence), matched according to age and gender, were retrospectively enrolled. All coronary segments were evaluated for overall image quality, evaluability, presence of CAD, coronary stenosis, plaque composition, plaque focality, and spotty calcification by four readers. Interobserver agreement was assessed using Fleiss' Kappa (κ) and intra-class correlation (ICC). Widely used clinical parameters (overall scan quality, presence of CAD, and determination of coronary stenosis) showed good agreement among the four readers, (ICC = 0.66, κ = 0.73, ICC = 0.74, respectively). When accounting for heart rate, body mass index, plaque location, and coronary stenosis above/below 50 %, interobserver agreement for plaque composition, presence of CAD, and coronary stenosis improved to either good or excellent, (κ = 0.61, κ = 0.81, ICC = 0.78, respectively). Spotty calcification was the least reproducible parameter investigated (κ = 0.33). Across subpopulations, reproducibility of coronary plaque characteristics generally decreased with increasing CAD prevalence except for plaque composition, (limits of agreement: ±2.03, ±1.96, ±1.79 for low, intermediate and high CAD prevalence, respectively). 320-slice MDCT can be used to assess coronary plaque characteristics, except for spotty calcification. Reproducibility estimates are influenced by heart rate, body size, plaque location, and degree of luminal stenosis.

  12. Evaluation of postoperative lymphocele according to amounts and symptoms by using 3-dimensional CT volumetry in kidney transplant recipients

    PubMed Central

    Jun, Heungman; Hwang, Sung Ho; Lim, Sungyoon; Kim, Myung Gyu

    2016-01-01

    Purpose To analyze the risk factors for postoperative lymphocele, for predicting and preventing complications. Methods We evaluated 92 kidney transplant recipients with multidetector CT (MDCT) at 1-month posttransplantation. From admission and 1-month postoperative records, data including diabetes, dialysis type, immunosuppressant use, steroid pulse therapy, and transplantation side were collected. Lymphocele volume was measured with 3-dimensional reconstructed, nonenhanced MDCT at one month postoperatively. The correlations between risk factors and lymphocele volume and between risk factors and symptomatic lymphocele (SyL) were analyzed. The cutoff was calculated by using the receiver operating characteristic (ROC) curve for SyL volume. Results Among 92 recipients, the mean volume was 44.53 ± 176.43 cm3 and 12 had SyL. Univariable analysis between risk factors and lymphocele volume indicated that donor age, retransplantation, and inferiorly located lymphocele were statistically significant. The ROC curve for SyL showed that 33.20 cm3 was the cutoff, with 83.3% sensitivity and 93.7% specificity. On univariable analysis between risk factors and SyL, steroid pulse, inferiorly located lymphocele, and >33.20 cm3 were statistically significant. Multivariable analysis indicated that steroid pulse, >33.20 cm3, and serum creatinine level at one month were significant factors. Conclusion Risk factors including donor age, retransplantation, steroid pulse therapy, and inferiorly located lymphocele are important predictors of large lymphoceles or SyL. In high-risk recipients, careful monitoring of renal function and early image surveillance such as CT or ultrasound are recommended. If the asymptomatic lymphocele is >33.20 cm3 or located inferiorly, early interventions can be considered while carefully observing the changes in symptoms.

  13. A method to analyse observer disagreement in visual grading studies: example of assessed image quality in paediatric cerebral multidetector CT images.

    PubMed

    Ledenius, K; Svensson, E; Stålhammar, F; Wiklund, L-M; Thilander-Klang, A

    2010-07-01

    The purpose was to demonstrate a non-parametric statistical method that can identify and explain the components of observer disagreement in terms of systematic disagreement as well as additional individual variability, in visual grading studies. As an example, the method was applied to a study where the effect of reduced tube current on diagnostic image quality in paediatric cerebral multidetector CT (MDCT) images was investigated. Quantum noise, representing dose reductions equivalent to steps of 20 mA, was artificially added to the raw data of 25 retrospectively selected paediatric cerebral MDCT examinations. Three radiologists, blindly and randomly, assessed the resulting images from two different levels of the brain with regard to the reproduction of high- and low-contrast structures and overall image quality. Images from three patients were assessed twice for the analysis of intra-observer disagreement. The intra-observer disagreement in test-retest assessments could mainly be explained by a systematic change towards lower image quality the second time the image was reviewed. The inter-observer comparisons showed that the paediatric radiologist was more critical of the overall image quality, while the neuroradiologists were more critical of the reproduction of the basal ganglia. Differences between the radiologists regarding the extent to which they used the whole classification scale were also found. The statistical method used was able to identify and separately measure a presence of bias apart from additional individual variability within and between the radiologists which is, at the time of writing, not attainable by any other statistical approach suitable for paired, ordinal data.

  14. The MRI geyser sign: acromioclavicular joint cysts in the setting of a chronic rotator cuff tear.

    PubMed

    Cooper, H John; Milillo, Ralph; Klein, Devon A; DiFelice, Gregory S

    2011-06-01

    We present the case of a 71-year-old man with a large acromioclavicular (AC) joint cyst successfully managed with surgical excision. AC joint cysts are soft tissue masses generally signifying underlying rotator cuff pathology. Traditionally, these cysts were identified with shoulder arthrography as a "geyser" of fluid escaping through the AC joint. Magnetic resonance imaging (MRI) is today's preferred imaging modality; we describe the MRI equivalent of the "geyser sign," signifying synovial fluid escaping through the cuff defect, across the subacromial bursa, and decompressing superiorly through a degenerated AC joint. Surgical management is preferred for symptomatic cysts. Based on a review of limited retrospective case series, recommendations for management of these lesions are as follows. Repair of the rotator cuff is preferable whenever possible. In the case of an irreparable defect, good results can be achieved through excisional AC joint arthroplasty and resection of the cyst base. Aspiration of these cysts should not be attempted, due to the high recurrence rate and potential for a draining sinus. Hemiarthroplasty also may be effective in indirectly decompressing these cysts; but given the invasive nature of this procedure, it should be reserved for patients who are also symptomatic from cuff arthropathy.

  15. Basic principles of nuclear medicine techniques for detection and evaluation of trauma and sports medicine injuries.

    PubMed

    Matin, P

    1988-04-01

    Nuclear medicine skeletal imaging is a very sensitive technique for evaluating bone and muscle abnormalities because it can detect minor changes in metabolism and blood flow. The specificity of bone imaging, however, depends on the ability of the nuclear medicine physician to make a differential diagnosis. To aid in making a specific diagnosis, this article describes the various patterns of abnormality in stress fractures, tibial stress syndrome (shin splints), compartment syndrome, enthesopathy, and traumatic fractures. The characteristic scintigraphic appearance of joint injuries, muscle injuries (rhabdomyolysis), and radionuclide arthrography is discussed and the way the scan patterns change with time in these various disorders is described. A brief summary of the basic anatomy and physiology of bone and muscle in normal and injured tissue is presented and the basic mechanisms which cause the various abnormal scan patterns is postulated. In addition, a staging system for stress fractures is presented to help direct the referring physician toward the proper management of the injured patient. In most cases, nuclear medicine skeletal imaging can be used to differentiate between acute muscle injury, tibial stress syndrome, skeletal injury (periosteal reaction, stress fracture, and traumatic fracture) or an abnormality that is entirely associated with the joint or connective tissue. This differential diagnosis is easier if the nuclear medicine procedure is performed within a few days after the onset of injury.

  16. Imaging of the acetabular labrum.

    PubMed

    Thomas, James D; Li, Zhi; Agur, Anne M; Robinson, Philip

    2013-07-01

    The evaluation and proposed relevance of acetabular labral tears has rapidly evolved over the last decade due to the recognition of femoroacetabular impingement, an increase in the number of surgical options, and improved imaging of the hip with MR arthrography and 3-T MR protocols. The acetabular labrum, stabilizing the hip joint, provides a seal, enhancing fluid lubrication, maintains synovial pressure, and prevents direct contact of the articular surfaces. The labrum takes on a weightbearing role at the extremes of motion with excessive forces seen in a great number of athletic activities thought to contribute to tearing. Approximately 25% of labral tears are not associated with any specific injury or traumatic event with the underlying etiology thought to be repetitive microtrauma. This article reviews the anatomy of the acetabular labrum and discusses the five most commonly occurring etiologies of labral tears: trauma, femoroacetabular impingement, hip hypermobility, dysplasia, and degeneration. We also review the surgical and MR classification of labral tears and describe potential pitfalls in image interpretation. PMID:23787979

  17. Synovial fluid dynamics with small disc perforation in temporomandibular joint.

    PubMed

    Xu, Y; Zhan, J; Zheng, Y; Han, Y; Zhang, Z; Xi, Y; Zhu, P

    2012-10-01

    The articular disc plays an important role as a stress absorber in joint movement, resulting in stress reduction and redistribution in the temporomandibular joint (TMJ). The flow of synovial fluid in the TMJ may follow a regular pattern during movement of the jaw. We hypothesised that the regular pattern is disrupted when the TMJ disc is perforated. By computed tomography arthrography, we studied the upper TMJ compartment in patients with small disc perforation during jaw opening-closing at positions from 0 to 3 cm. Finite element fluid dynamic modelling was accomplished to analyse the pattern of fluid flow and pressure distribution during the movements. The results showed that the fluid flow in the upper compartment generally formed an anticlockwise circulation but with local vortexes with the jaw opening up to 2 cm. However, when the jaw opening-closing reached 3 cm, an abnormal flow field and the fluid pressure change associated with the perforation may increase the risk of perforation expansion or rupture and is unfavourable for self-repair of the perforated disc. PMID:22582815

  18. Extracorporeal shockwave therapy in a dog with chronic bicipital tenosynovitis.

    PubMed

    Venzin, C; Ohlerth, S; Koch, D; Spreng, D

    2004-03-01

    A 15-month-old, spayed female, Bernese mountain dog was presented to the Institute of Small Animal Surgery at the University of Zurich because of chronic left forelimb lameness. The referring veterinarian diagnosed pain in the left shoulder region and had treated the dog with systemic non-steroidal anti-inflammatory drugs and restricted exercise for a two-week period. The follow-up examination revealed only minimal improvement and therefore, the dog was referred for further diagnostic evaluation. Chronic bicipital tenosynovitis and tendinitis of the infraspinatus muscle was diagnosed based on survey radiographs, arthrography, ultrasound, computed tomography (CT), and synovial fluid cytology. The dog underwent three sessions of extracorporeal shockwave therapy and substantial clinical improvement was observed. On follow-up examinations, only mild left forelimb lameness was evident following exercise, and changes in the intertubercular groove and at the supraglenoid tuberosity appeared less active on radiographs and CT. However, six months following treatment, mild degenerative joint disease was apparent.

  19. Musculoskeletal interventional radiology: ultrasound and CT.

    PubMed

    Martel Villagrán, J; Bueno Horcajadas, Á; Agrela Rojas, E

    2016-05-01

    We aim to describe imaging-guided (ultrasound and CT) interventional techniques in the musculoskeletal system that can be performed by general radiologists, whether in hospitals, primary care clinics, private offices, or other settings. The first requirement for doing these procedures is adequate knowledge of the anatomy of the musculoskeletal system. The second requirement is to inform the patient thoroughly about the technique, the risks involved, and the alternatives available in order to obtain written informed consent. The third requirement is to ensure that the procedure is performed in accordance with the principles of asepsis in relation to the puncture zone and to all the material employed throughout the procedure. The main procedures that can be done under ultrasound guidance are the following: fine needle aspiration cytology (FNAC), core needle biopsy (CNB), diagnostic and/or therapeutic arthrocentesis, drainage of juxta-articular fluid collections, drainage of abscesses, drainage of hematomas, treatment of Baker's cyst, treatment of ganglia, treatment of bursitis, infiltrations and treatment of plantar fasciitis, plantar fibrosis, epicondylitis, Achilles tendinopathy, and Morton's neuroma, puncture and lavage of calcifications in calcifying tendinopathy. We also review the following CT-guided procedures: diagnosis of spondylodiscitis, FNAC of metastases, arthrography, drainages. Finally, we also mention more complex procedures that can only be done in appropriate settings: bone biopsies, treatment of facet joint pain, radiofrequency treatment. PMID:27134018

  20. Meniscal ossicles in large non-domestic cats.

    PubMed

    Walker, Michael; Phalan, David; Jensen, James; Johnson, James; Drew, Mark; Samii, Valerie; Henry, George; McCauley, Jessica

    2002-01-01

    Radiographs of the stifles of 6 species of 34 large, non-domestic cats were reviewed foremost for the presence of meniscal ossicles and then for the presence of the other potential four sesamoids. The animals in the review included 12 lions, 7 tigers, 7 cougars, 3 leopards, 3 bobcats, and 2 jaguars. Fluoroscopy, arthrography, computed tomography, necropsy, and histology were also used to evaluate the stifles of one tiger after euthanasia. Ossicles were found in the region of the cranial horn of the medial meniscus in most of the lions, tigers, leopards, and jaguars. These ossicles were found in half of the cougars but in none of the bobcats. Among the large, non-domestic cats, meniscal ossicles had been reported previously only in Bengal tigers. The lions, tigers, and leopards having meniscal ossicles appeared to have a lateral but often not a medial fabella of the gastrocnemius muscle, an observation previously unreported. Popliteal sesamoids and patellas were present in all the skeletally mature cats.

  1. Lateral ankle stabilization. Modified Lee and Chrisman-Snook.

    PubMed

    Saltrick, K R

    1991-07-01

    Chronic lateral ankle instability is not always a severe disability, but surgical reconstruction may be necessary in patients with instability or when conservative measures fail. Although recent articles by Ahlgren and Larsson and Bergsten et al provide evidence of satisfactory results with late ligamentous repair of chronic ankle instability via imbrication, lateral ankle stabilization procedures that use tenodesing of fasciodesing techniques continue to provide good results. Prolonged disability after acute lateral ankle ligament disruption has been reported in 20% of patients. With long-term instability, uneven stress distribution with recurrent sprains can lead to osteoarthritis. Various methods for evaluation of the chronically unstable ankle include inversion stress testing, anterior drawer sign, arthrography, and tenography. All of these methods are controversial with false negative results, unreliability, and variations in measurements and interpretation being cited. With this in mind, radiographic instability must be correlated with mechanical and clinical instability. Once all of these findings are correlated the physician can determine the appropriate procedure that will provide the patient with long-term stability. Although more recent studies have addressed repair of chronic instability with ligamentous reinforcement or imbrication, these procedures remain controversial in lieu of Freeman's deafferentiation theory with loss of proprioception. There is also mechanical instability of the subtalar joint, which may also require stabilization. Use of the modified Lee and the Chrisman-Snook techniques as described have provided good results.

  2. Superior labrum anterior to posterior tears and glenohumeral instability.

    PubMed

    Virk, Mandeep S; Arciero, Robert A

    2013-01-01

    Cadaver experiments and clinical studies suggest that the superior labrum-biceps complex plays a role in glenohumeral stability. Superior labrum anterior to posterior (SLAP) tears can be present in acute and recurrent glenohumeral dislocations and contribute to glenohumeral instability. Isolated SLAP tears can cause instability, especially in throwing athletes. Diagnosing a SLAP tear on the basis of the clinical examination alone is difficult because of nonspecific history and physical examination findings and the presence of coexisting intra-articular lesions. Magnetic resonance arthrography is the imaging study of choice for diagnosing SLAP tears; however, arthroscopy remains the gold standard for diagnosis. Arthroscopy is the preferred technique for the repair of a type II SLAP tear and its variant types (V through X) in acute glenohumeral dislocations and instability in younger populations. Clinical outcome studies report a low recurrence of glenohumeral instability after the arthroscopic repair of a SLAP tear in addition to a Bankart repair. Long-term follow-up studies and further advances in arthroscopic fixation techniques will allow a better understanding and improvement in outcomes in patients with SLAP tears associated with glenohumeral instability. PMID:23395054

  3. The MRI geyser sign: acromioclavicular joint cysts in the setting of a chronic rotator cuff tear.

    PubMed

    Cooper, H John; Milillo, Ralph; Klein, Devon A; DiFelice, Gregory S

    2011-06-01

    We present the case of a 71-year-old man with a large acromioclavicular (AC) joint cyst successfully managed with surgical excision. AC joint cysts are soft tissue masses generally signifying underlying rotator cuff pathology. Traditionally, these cysts were identified with shoulder arthrography as a "geyser" of fluid escaping through the AC joint. Magnetic resonance imaging (MRI) is today's preferred imaging modality; we describe the MRI equivalent of the "geyser sign," signifying synovial fluid escaping through the cuff defect, across the subacromial bursa, and decompressing superiorly through a degenerated AC joint. Surgical management is preferred for symptomatic cysts. Based on a review of limited retrospective case series, recommendations for management of these lesions are as follows. Repair of the rotator cuff is preferable whenever possible. In the case of an irreparable defect, good results can be achieved through excisional AC joint arthroplasty and resection of the cyst base. Aspiration of these cysts should not be attempted, due to the high recurrence rate and potential for a draining sinus. Hemiarthroplasty also may be effective in indirectly decompressing these cysts; but given the invasive nature of this procedure, it should be reserved for patients who are also symptomatic from cuff arthropathy. PMID:21869946

  4. Superior labral anterior posterior lesions of the shoulder: Current diagnostic and therapeutic standards

    PubMed Central

    Popp, Dominik; Schöffl, Volker

    2015-01-01

    Surgical treatment of superior labral anterior posterior (SLAP) lesion becomes more and more frequent which is the consequence of evolving progress in both, imaging and surgical technique as well as implants. The first classification of SLAP lesions was described in 1990, a subdivision in four types existed. The rising comprehension of pathology and pathophysiology in SLAP lesions contributed to increase the types in SLAP classification to ten. Concerning the causative mechanism of SLAP lesions, acute trauma has to be differed from chronic degeneration. Overhead athletes tend to develop a glenohumeral internal rotation deficit which forms the basis for two controversial discussed potential mechanisms of pathophysiology in SLAP lesions: Internal impingement and peel-back mechanism. Clinical examination often remains unspecific whereas soft tissue imaging such as direct or indirect magnetic resonance arthrography has technically improved and is regarded to be indispensable in detection of SLAP lesions. Concomitant pathologies as Bankart lesions, rotator cuff tears or perilabral cysts should be taken into consideration when planning a personalized therapeutic strategy. In addition, normal variants such as sublabral recess, sublabral hole, Buford complex and other less common variants have to be distinguished. The most frequent SLAP type II needs a sophisticated approach when surgical teatment comes into consideration. While SLAP repair is considered to be the standard operative option, overhead athletes benefit from a biceps tenodesis because improved patient-reported satisfaction and higher rate of return to pre-injury level of sports has been reported. PMID:26495243

  5. A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis

    PubMed Central

    Lefevre, Nicolas; Naouri, Jean Francois; Herman, Serge; Gerometta, Antoine; Klouche, Shahnaz; Bohu, Yoann

    2016-01-01

    The main objective of this review was to present a synthesis of the current literature in order to provide a useful tool to clinician in radiologic analysis of the meniscus. All anatomical descriptions were clearly illustrated by MRI, arthroscopy, and/or drawings. The value of standard radiography is extremely limited for the assessment of meniscal injuries but may be indicated to obtain a differential diagnosis such as osteoarthritis. Ultrasound is rarely used as a diagnostic tool for meniscal pathologies and its accuracy is operator-dependent. CT arthrography with multiplanar reconstructions can detect meniscus tears that are not visible on MRI. This technique is also useful in case of MRI contraindications, in postoperative assessment of meniscal sutures and the condition of cartilage covering the articular surfaces. MRI is the most accurate and less invasive method for diagnosing meniscal lesions. MRI allows confirming and characterizing the meniscal lesion, the type, the extension, its association with a cyst, the meniscal extrusion, and assessing cartilage and subchondral bone. New 3D-MRI in three dimensions with isotropic resolution allows the creation of multiplanar reformatted images to obtain from an acquisition in one sectional plane reconstructions in other spatial planes. 3D MRI should further improve the diagnosis of meniscal tears. PMID:27057352

  6. Cationic gadolinium chelate for magnetic resonance imaging of cartilaginous defects.

    PubMed

    Nwe, Kido; Huang, Ching-Hui; Qu, Feini; Warden-Rothman, Robert; Zhang, Clare Y; Mauck, Robert L; Tsourkas, Andrew

    2016-05-01

    The ability to detect meniscus defects by magnetic resonance arthrography (MRA) can be highly variable. To improve the delineation of fine tears, we synthesized a cationic gadolinium complex, (Gd-DOTA-AM4 )(2+) , that can electrostatically interact with Glycosaminoglycans (GAGs). The complex has a longitudinal relaxivity (r1) of 4.2 mM(-1) s(-1) and is highly stable in serum. Its efficacy in highlighting soft tissue tears was evaluated in comparison to a clinically employed contrast agent (Magnevist) using explants obtained from adult bovine menisci. In all cases, Gd-DOTA-AM4 appeared to improve the ability to detect the soft tissue defect by providing increased signal intensity along the length of the tear. Magnevist shows a strong signal near the liquid-meniscus interface, but much less contrast is observed within the defect at greater depths. This provides initial evidence that cationic contrast agents can be used to improve the diagnostic accuracy of MRA. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Detection of occult infection following total joint arthroplasty using sequential technetium-99m HDP bone scintigraphy and indium-111 WBC imaging

    SciTech Connect

    Johnson, J.A.; Christie, M.J.; Sandler, M.P.; Parks, P.F. Jr.; Homra, L.; Kaye, J.J.

    1988-08-01

    Preoperative exclusion or confirmation of periprosthetic infection is essential for correct surgical management of patients with suspected infected joint prostheses. The sensitivity and specificity of (/sup 111/In)WBC imaging in the diagnosis of infected total joint prostheses was examined in 28 patients and compared with sequential (/sup 99m/Tc)HDP/(/sup 111/In)WBC scintigraphy and aspiration arthrography. The sensitivity of preoperative aspiration cultures was 12%, with a specificity of 81% and an accuracy of 58%. The sensitivity of (/sup 111/In)WBC imaging alone was 100%, with a specificity of 50% and an accuracy of 65%. When correlated with the bone scintigraphy and read as sequential (/sup 99m/Tc)HDP/(/sup 111/In)WBC imaging, the sensitivity was 88%, specificity 95%, and accuracy 93%. This study demonstrates that (/sup 111/In)WBC imaging is an extremely sensitive imaging modality for the detection of occult infection of joint prostheses. It also demonstrates the necessity of correlating (/sup 111/In)WBC images with (/sup 99m/Tc)HDP skeletal scintigraphy in the detection of occult periprosthetic infection.

  8. Advanced Imaging in Femoroacetabular Impingement: Current State and Future Prospects.

    PubMed

    Bittersohl, Bernd; Hosalkar, Harish S; Hesper, Tobias; Tiderius, Carl Johan; Zilkens, Christoph; Krauspe, Rüdiger

    2015-01-01

    Symptomatic femoroacetabular impingement (FAI) is now a known precursor of early osteoarthritis (OA) of the hip. In terms of clinical intervention, the decision between joint preservation and joint replacement hinges on the severity of articular cartilage degeneration. The exact threshold during the course of disease progression when the cartilage damage is irreparable remains elusive. The intention behind radiographic imaging is to accurately identify the morphology of osseous structural abnormalities and to accurately characterize the chondrolabral damage as much as possible. However, both plain radiographs and computed tomography (CT) are insensitive for articular cartilage anatomy and pathology. Advanced magnetic resonance imaging (MRI) techniques include magnetic resonance arthrography and biochemically sensitive techniques of delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T1rho (T1ρ), T2/T2* mapping, and several others. The diagnostic performance of these techniques to evaluate cartilage degeneration could improve the ability to predict an individual patient-specific outcome with non-surgical and surgical care. This review discusses the facts and current applications of biochemical MRI for hip joint cartilage assessment covering the roles of dGEMRIC, T2/T2*, and T1ρ mapping. The basics of each technique and their specific role in FAI assessment are outlined. Current limitations and potential pitfalls as well as future directions of biochemical imaging are also outlined. PMID:26258129

  9. Utilizing pigment-producing fungi to add commercial value to American beech (Fagus grandifolia).

    PubMed

    Robinson, Sara C; Tudor, Daniela; Cooper, Paul A

    2012-02-01

    American beech (Fagus grandifolia) is an abundant, underutilized tree in certain areas of North America, and methods to increase its market value are of considerable interest. This research utilized pigment-producing fungi to induce color in American beech to potentially establish its use as a decorative wood. Wood samples were inoculated with Trametes versicolor, Xylaria polymorpha, Inonotus hispidus, and Arthrographis cuboidea to induce fungal pigmentation. Black pigmentation (T. versicolor, X. polymorpha, I. hispidus) was sporadic, occurred primarily on the surfaces of the heartwood, but not internally. Pink pigmentation (A. cuboidea) occurred throughout all of the tested beech samples, but was difficult to see in the heartwood due to the darker color of the wood. To increase the visibility of the pink stain, beech blocks were pretreated with T. versicolor for 4 weeks before being inoculated with A. cuboidea. This method significantly increased the saturation of the pink stain on both beech heartwood and sapwood, creating coloration similar to that found on sugar maple. This value-adding process should be particularly effective for small-scale wood pigmentation, and should help establish a market for this currently underutilized wood species. PMID:21931972

  10. Accuracy assessment of 3D bone reconstructions using CT: an intro comparison.

    PubMed

    Lalone, Emily A; Willing, Ryan T; Shannon, Hannah L; King, Graham J W; Johnson, James A

    2015-08-01

    Computed tomography provides high contrast imaging of the joint anatomy and is used routinely to reconstruct 3D models of the osseous and cartilage geometry (CT arthrography) for use in the design of orthopedic implants, for computer assisted surgeries and computational dynamic and structural analysis. The objective of this study was to assess the accuracy of bone and cartilage surface model reconstructions by comparing reconstructed geometries with bone digitizations obtained using an optical tracking system. Bone surface digitizations obtained in this study determined the ground truth measure for the underlying geometry. We evaluated the use of a commercially available reconstruction technique using clinical CT scanning protocols using the elbow joint as an example of a surface with complex geometry. To assess the accuracies of the reconstructed models (8 fresh frozen cadaveric specimens) against the ground truth bony digitization-as defined by this study-proximity mapping was used to calculate residual error. The overall mean error was less than 0.4 mm in the cortical region and 0.3 mm in the subchondral region of the bone. Similarly creating 3D cartilage surface models from CT scans using air contrast had a mean error of less than 0.3 mm. Results from this study indicate that clinical CT scanning protocols and commonly used and commercially available reconstruction algorithms can create models which accurately represent the true geometry.

  11. Cationic gadolinium chelate for magnetic resonance imaging of cartilaginous defects.

    PubMed

    Nwe, Kido; Huang, Ching-Hui; Qu, Feini; Warden-Rothman, Robert; Zhang, Clare Y; Mauck, Robert L; Tsourkas, Andrew

    2016-05-01

    The ability to detect meniscus defects by magnetic resonance arthrography (MRA) can be highly variable. To improve the delineation of fine tears, we synthesized a cationic gadolinium complex, (Gd-DOTA-AM4 )(2+) , that can electrostatically interact with Glycosaminoglycans (GAGs). The complex has a longitudinal relaxivity (r1) of 4.2 mM(-1) s(-1) and is highly stable in serum. Its efficacy in highlighting soft tissue tears was evaluated in comparison to a clinically employed contrast agent (Magnevist) using explants obtained from adult bovine menisci. In all cases, Gd-DOTA-AM4 appeared to improve the ability to detect the soft tissue defect by providing increased signal intensity along the length of the tear. Magnevist shows a strong signal near the liquid-meniscus interface, but much less contrast is observed within the defect at greater depths. This provides initial evidence that cationic contrast agents can be used to improve the diagnostic accuracy of MRA. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26853708

  12. Superior labral anterior posterior lesions of the shoulder: Current diagnostic and therapeutic standards.

    PubMed

    Popp, Dominik; Schöffl, Volker

    2015-10-18

    Surgical treatment of superior labral anterior posterior (SLAP) lesion becomes more and more frequent which is the consequence of evolving progress in both, imaging and surgical technique as well as implants. The first classification of SLAP lesions was described in 1990, a subdivision in four types existed. The rising comprehension of pathology and pathophysiology in SLAP lesions contributed to increase the types in SLAP classification to ten. Concerning the causative mechanism of SLAP lesions, acute trauma has to be differed from chronic degeneration. Overhead athletes tend to develop a glenohumeral internal rotation deficit which forms the basis for two controversial discussed potential mechanisms of pathophysiology in SLAP lesions: Internal impingement and peel-back mechanism. Clinical examination often remains unspecific whereas soft tissue imaging such as direct or indirect magnetic resonance arthrography has technically improved and is regarded to be indispensable in detection of SLAP lesions. Concomitant pathologies as Bankart lesions, rotator cuff tears or perilabral cysts should be taken into consideration when planning a personalized therapeutic strategy. In addition, normal variants such as sublabral recess, sublabral hole, Buford complex and other less common variants have to be distinguished. The most frequent SLAP type II needs a sophisticated approach when surgical teatment comes into consideration. While SLAP repair is considered to be the standard operative option, overhead athletes benefit from a biceps tenodesis because improved patient-reported satisfaction and higher rate of return to pre-injury level of sports has been reported.

  13. Magnetic resonance imaging in glenohumeral instability

    PubMed Central

    Jana, Manisha; Gamanagatti, Shivanand

    2011-01-01

    The glenohumeral joint is the most commonly dislocated joint of the body and anterior instability is the most common type of shoulder instability. Magnetic resonance (MR) imaging, and more recently, MR arthrography, have become the essential investigation modalities of glenohumeral instability, especially for pre-procedure evaluation before arthroscopic surgery. Injuries associated with glenohumeral instability are variable, and can involve the bones, the labor-ligamentous components, or the rotator cuff. Anterior instability is associated with injuries of the anterior labrum and the anterior band of the inferior glenohumeral ligament, in the form of Bankart lesion and its variants; whereas posterior instability is associated with reverse Bankart and reverse Hill-Sachs lesion. Multidirectional instability often has no labral pathology on imaging but shows specific osseous changes such as increased chondrolabral retroversion. This article reviews the relevant anatomy in brief, the MR imaging technique and the arthrographic technique, and describes the MR findings in each type of instability as well as common imaging pitfalls. PMID:22007285

  14. Evaluation and treatment of young adults with femoro-acetabular impingement secondary to Perthes' disease.

    PubMed

    Eijer, H; Podeszwa, D A; Ganz, R; Leunig, M

    2006-01-01

    Hip pain and loss of motion in young adults with previous Legg-Calve-Perthes-Disease may be caused by anterior femoro-acetabular impingement. Eleven patients (12 hips) with the chief complaint of groin pain and significant proximal femoral deformity were treated. Gadolinium-enhanced magnetic resonance arthrography in ten patients indicated labral injury and adjacent acetabular cartilage lesions in nine hips. A surgical dislocation of each hip confirmed that there was impingement induced intra-articular injury consistent with the pathology indicated on the MRI. Reshaping of the femoral head, with correction of the femoral head/neck offset, and treatment of the acetabular rim pathology was performed for each hip in conjunction with other procedures for the proximal femur. Correction of the impingement and increased range of motion could be visualized intra-operatively. At a mean follow-up of 33 months, half of all patients were pain-free and all had improvement in pain compared with preoperatively. Ten patients had an improved range of motion and two a slight decrease. No additional necrosis following the dislocation of the femoral head was seen.; PMID:19219805

  15. Groin pain after open FAI surgery: the role of intraarticular adhesions.

    PubMed

    Beck, Martin

    2009-03-01

    Femoroacetabular impingement (FAI) is an established cause of osteoarthrosis of the hip. Surgery is intended to remove the cause of impingement with hip dislocation and resection of osseous prominences of the acetabular rim and of the femoral head-neck junction. Using the Merle d'Aubigné score and qualitative categories, recent studies suggest good to excellent outcomes in 75% to 80% of patients after open surgery with dislocation of the femoral head. Unsatisfactory outcome is mainly related to pain, located either in the area of the greater trochanter or in the groin. There are several reasons for persisting groin pain. Joint degeneration with joint space narrowing and/or osteophyte formation, insufficient correction of the acetabula, and femoral pathology are known factors for unsatisfactory outcome. Recently, intraarticular adhesions between the femoral neck and joint capsule have been identified as an additional cause of postoperative groin pain. The adhesions form between the joint capsule and the resected area on the femoral neck and may lead to soft tissue impingement. MR-arthrography is used for diagnosis and the adhesions can be treated successfully by arthroscopy. While arthroscopic resection improves outcome it is technically demanding. Avoiding the formation of adhesions is important and is perhaps best accomplished by passive motion exercises after the initial surgery. PMID:19082679

  16. US appearance of partial-thickness supraspinatus tendon tears: Application of the string theory. Pictorial essay.

    PubMed

    Guerini, H; Fermand, M; Godefroy, D; Feydy, A; Chevrot, A; Morvan, G; Gault, N; Drapé, J L

    2012-02-01

    The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination.A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT).

  17. SLAP tear associated with a minimally displaced proximal humerus fracture.

    PubMed

    Kendall, Corey B; Tanner, Stephanie L; Tolan, Stefan J

    2007-12-01

    Nondisplaced proximal humerus fracture may be associated with soft tissue injury. This case report examines 2 cases of superior labral anterior-posterior (SLAP) tears in association with nondisplaced fractures of the proximal humerus. In the first case, the patient fell from a jet ski, causing a traction injury to his arm. A greater tuberosity fracture was identified. Magnetic resonance imaging (MRI) did not reveal a definitive labral tear. After conservative management had failed, a type IV SLAP tear and a small rotator cuff tear were arthroscopically identified and repaired. In the second case, a power company lineman fell from a lift and attempted to hold on with his dominant arm. A nondisplaced greater tuberosity and a surgical neck fracture were discovered. MR arthrography revealed no evidence of SLAP tear. Four months after injury, a type II SLAP tear was arthroscopically identified and repaired. In these 2 cases, the presence of the fracture likely slowed operative intervention because pain was attributed to the fracture itself, and not to the SLAP tear. If patients do not follow the usual course of improvement after a proximal humerus fracture from a superior traction mechanism, consideration should be given to associated superior labral tears that may require surgical intervention.

  18. Cartilaginous and ligamentous degeneration of the wrist. Anatomic study.

    PubMed

    Fortems, Y; de Smet, L; Fabry, G

    1994-01-01

    The growing precision of diagnostic techniques (MRI, arthrography, arthroscopy) and the consequent increase of the diagnosis of cartilaginous and ligamentous lesions of the wrist led us to undertake a detailed anatomical study of the carpus and to extend this study to the search for correlations between these lesions and the radio-ulnar index. Fifty one cadaveric wrists were dissected from an elderly population (mean age of 76 years). Cartilaginous lesions were found in two-thirds of radioulnar joints of the wrist with a marked predominance for the lunate bone (43%). The triangular cartilage of the fibrocartilaginous complex (TFCC) was perforated in 23 wrists (46%). We established a correlation between the radio-ulnar index and perforations of the TFCC (p < 0.05), as well as the thickness of this structure (p < 0.05). The relationship between age and rupture of intrinsic ligaments (p < 0.05), and the radio-ulnar index (p < 0.05) and age was also established. We present our figures, discuss the clinical implications, and draw the following conclusions from this study. 1) The carpus is a complex joint which is subject to age-related degeneration. 2) The large number of cartilaginous lesions observed in this study must be taken into account in the interpretation of MRI and the "over" precise results of arthroscopy. PMID:7531478

  19. Ultrasonography as a diagnostic tool in assessing deltoid ligament injury in supination external rotation fractures of the ankle.

    PubMed

    Henari, Shwan; Banks, Louisa N; Radovanovic, Ingrid; Radiovanovic, Ingrid; Queally, Joseph; Morris, Seamus

    2011-10-01

    The medial deltoid ligament is the primary stabilizing structure in the ankle joint following lateral malleolar fracture. However, medial deltoid ligament ruptures are difficult to diagnose using current imaging modalities. We hypothesized that ultrasonography can be used to accurately allow early clinical assessment of ankle fracture stability, thereby negating the need to perform plain film stress views of the acutely injured ankle. This prospective study included 12 patients (age range, 18-72) with supination external rotation fractures requiring operative fixation. Following induction of anesthesia, ultrasonography examination was performed, followed by an arthrogram under fluoroscopic screening. Radiographs, ultrasonography, and arthrographic findings were compared. There was 100% correlation between ultrasonography and arthrogram findings. Ultrasonography accurately diagnosed medial deltoid rupture with a sensitivity of 100% and specificity of 100%. Plain film radiographs of the ankle had a sensitivity of 57.1% and a specificity of 60%. The difference between these was significant (χ(2)=.0091). This study demonstrates diagnostic ultrasonography to be an accurate diagnostic modality in assessing medial deltoid ligament integrity in patients with supination external rotation fractures. It offers the same sensitivity and specificity as arthrography without the need for additional invasive procedures. Its relative ease of use and lack of ionizing radiation make it a potentially useful tool, particularly in a busy trauma service.

  20. Advanced Imaging in Femoroacetabular Impingement: Current State and Future Prospects

    PubMed Central

    Bittersohl, Bernd; Hosalkar, Harish S.; Hesper, Tobias; Tiderius, Carl Johan; Zilkens, Christoph; Krauspe, Rüdiger

    2015-01-01

    Symptomatic femoroacetabular impingement (FAI) is now a known precursor of early osteoarthritis (OA) of the hip. In terms of clinical intervention, the decision between joint preservation and joint replacement hinges on the severity of articular cartilage degeneration. The exact threshold during the course of disease progression when the cartilage damage is irreparable remains elusive. The intention behind radiographic imaging is to accurately identify the morphology of osseous structural abnormalities and to accurately characterize the chondrolabral damage as much as possible. However, both plain radiographs and computed tomography (CT) are insensitive for articular cartilage anatomy and pathology. Advanced magnetic resonance imaging (MRI) techniques include magnetic resonance arthrography and biochemically sensitive techniques of delayed gadolinium-enhanced MRI of cartilage (dGEMRIC), T1rho (T1ρ), T2/T2* mapping, and several others. The diagnostic performance of these techniques to evaluate cartilage degeneration could improve the ability to predict an individual patient-specific outcome with non-surgical and surgical care. This review discusses the facts and current applications of biochemical MRI for hip joint cartilage assessment covering the roles of dGEMRIC, T2/T2*, and T1ρ mapping. The basics of each technique and their specific role in FAI assessment are outlined. Current limitations and potential pitfalls as well as future directions of biochemical imaging are also outlined. PMID:26258129

  1. Meniscal ossicles in large non-domestic cats.

    PubMed

    Walker, Michael; Phalan, David; Jensen, James; Johnson, James; Drew, Mark; Samii, Valerie; Henry, George; McCauley, Jessica

    2002-01-01

    Radiographs of the stifles of 6 species of 34 large, non-domestic cats were reviewed foremost for the presence of meniscal ossicles and then for the presence of the other potential four sesamoids. The animals in the review included 12 lions, 7 tigers, 7 cougars, 3 leopards, 3 bobcats, and 2 jaguars. Fluoroscopy, arthrography, computed tomography, necropsy, and histology were also used to evaluate the stifles of one tiger after euthanasia. Ossicles were found in the region of the cranial horn of the medial meniscus in most of the lions, tigers, leopards, and jaguars. These ossicles were found in half of the cougars but in none of the bobcats. Among the large, non-domestic cats, meniscal ossicles had been reported previously only in Bengal tigers. The lions, tigers, and leopards having meniscal ossicles appeared to have a lateral but often not a medial fabella of the gastrocnemius muscle, an observation previously unreported. Popliteal sesamoids and patellas were present in all the skeletally mature cats. PMID:12088319

  2. Wrist arthroscopy: a prospective analysis of 53 post-traumatic carpal injuries.

    PubMed

    Sennwald, G R; Zdravkovic, V

    1997-09-01

    We carried out a prospective study of 53 consecutive patients who had sustained a serious wrist injury. Patients who presented with a previous condition or who had undergone surgery to the wrist were excluded. History, clinical findings, standard radiographs and arthrography were correlated with the uninjured side and with arthroscopic findings. The radiolunate (RL) angle of the injured wrist differed significantly from that of the "normal" wrist (p = 0.088). POssible correlations within the whole group were studied by multivariate analysis, particularly k-means clustering, a procedure which enables the detection of natural groups. We found that ligamentous tears at the triquetrum in the midcarpal joint significantly (p = 0.004) affected the equilibrium of the proximal row defined by clustering with the RL and scapholunate (SL) angles. The use of multivariate analysis techniques in combination with cross tabulation for the surgery of intracarpal ligamentous abnormalities seen at arthroscopy might help us to define better the function of the ligaments of the wrist. These findings, of little help in daily practice, might be important for clinical research.

  3. Evaluation of motion compensation approaches for soft tissue navigation

    NASA Astrophysics Data System (ADS)

    Krücker, Jochen; Xu, Sheng; Glossop, Neil; Pritchard, William F.; Karanian, John; Chiesa, Alberto; Wood, Bradford J.

    2008-03-01

    Organ motion was quantified and motion compensation strategies for soft-tissue navigation were evaluated in a porcine model. Organ motion due to patient repositioning, and respiratory motion during ventilated breathing were quantified. Imaging was performed on a 16-slice CT scanner. Organ motion due to repositioning was studied by attaching 7 external skin fiducials and inserting 7 point fiducials in the livers of ventilated pigs. The pigs were imaged repeatedly in supine and decubitus positions. Registrations between the images were obtained using either all external fiducials or 6 of the 7 internal fiducials. Target registration errors (TRE) were computed by using the leave-one-out technique. Respiratory organ motion was studied by inserting 7 electromagnetically (EM) tracked needles in the livers of 2 pigs. One needle served as primary target, the remaining six served as reference needles. In addition, 6 EM tracked skin fiducials, 5 passive skin fiducials, and one dynamic reference tracker were attached. Registrations were obtained using three different methods: Continuous registration with the tracking data from internal and external tracked fiducials, and one-time registration using the passive skin fiducials and a tracked pointer with dynamic reference tracking. The TRE for registering images obtained in supine position after an intermittent decubitus position ranged from 3.3 mm to 24.6 mm. Higher accuracy was achieved with internal fiducials (mean TRE = 6.4 mm) than with external fiducials (mean TRE = 16.7 mm). During respiratory motion, the FRE and TRE were shown to be correlated and were used to demonstrate automatic FRE-based gating. Tracking of target motion relative to a reference time point was achieved by registering nearby reference trackers with rigid and affine transformations. Linear motion models based on external and internal reference trackers were shown to reduce the target motion by up to 63% and 90%, respectively.

  4. Accessible or Inaccessible? Diagnostic Efficacy of CT-Guided Core Biopsies of Head and Neck Masses

    SciTech Connect

    Cunningham, Jane D. McCusker, Mark W.; Power, Sarah; PearlyTi, Joanna; Thornton, John; Brennan, Paul; Lee, Michael J.; O’Hare, Alan; Looby, Seamus

    2015-04-15

    PurposeTissue sampling of lesions in the head and neck is challenging due to complex regional anatomy and sometimes necessitates open surgical biopsy. However, many patients are poor surgical candidates due to comorbidity. Thus, we evaluated the use of CT guidance for establishing histopathological diagnosis of head and neck masses.MethodsAll consecutive patients (n = 22) who underwent CT-guided core biopsy of head or neck masses between April 2009 and August 2012 were retrospectively reviewed using the departmental CT interventional procedures database. The indication for each biopsy performed was to establish or exclude a diagnosis of neoplasia in patients with suspicious head or neck lesions found on clinical examination or imaging studies. Patients received conscious sedation and 18 G, semiautomated core needle biopsies were performed by experienced neuroradiologists using 16-slice multidetector row CT imaging guidance (Somatom Definition Siemens Medical Solutions, Germany). Histopathology results of each biopsy were analysed.ResultsSixteen of 22 biopsies that were performed (73 %) yielded a pathological diagnosis. Anatomic locations biopsied included: masticator (n = 7), parapharyngeal (n = 3), parotid (n = 3), carotid (n = 3), perivertebral (n = 3), pharyngeal (n = 2), and retropharyngeal (n = 1) spaces. Six biopsies (27 %) were nondiagnostic due to inadequate tissue sampling, particularly small biopsy sample size and failure to biopsy the true sampling site due to extensive necrosis. No major complications were encountered.ConclusionsThe use of CT guidance to perform core biopsies of head and neck masses is an effective means of establishing histopathological diagnosis and reduces the need for diagnostic open surgical biopsy and general anaesthesia.

  5. SU-E-I-86: Evaluation of the New RaySafe Unfors X2 Dosimetry System

    SciTech Connect

    Heintz, P; Chambers, G; Sandoval, D

    2014-06-01

    Purpose: To evaluate the new RaySafe Unfors X2 (X2) dosimetry system and compare it to the operation of the RaySafe Unfors Xi (Xi) and Radcal Accugold (RCAG) dosimetry systems. The comparison was done for the radiographic/fluoroscopic detectors, mammography detectors and the CT ionization chambers. Methods: This study used several R/F rooms, GE AMX4 portable x-ray unit, Siemens Biograph 16 slice CT scanner and a Hologic Dimensions mammography unit to evaluate the dosimetry systems. The three X2 detectors were compared to similar detectors of the older Xi and RCAG detectors under clinical conditions used for diagnostic medical physics testing. Measurements of kVp, HVL and exposure were made under identical conditions. Results: For radiography and fluoroscopy the three systems agreed to within +2 kVp in the 60 to 140 kVp range, HVL measurements agreed to within +2 mm Al and the exposures agreed to within +5%. The RCAG 6 cc ionization chamber measured at least 3% higher than the diode systems. The X2 R/F detector appeared to be transparent to the fluoroscopy AEC system. For exposures made using both the CT ACR dose phantoms, the X2 agreed to within +3% of the other two systems. For mammography measurements, the three systems agreed to within +0.4kVp (25-49 kVp range), HVL measurements agreed to within +0.05 mm Al and the exposures agreed to within +1% of the ionization chamber. Conclusion: The X2 system is a new version of the older Xi system. The system is faster, more robust, very easy to use, has a larger dynamic range, produced less errors and stores 1000 exposures. The measurements showed that the system performs well in the clinical environment and the X2 is within + 5% agreement of the other two calibrated systems.

  6. SU-E-T-64: CG-Based Radiation Therapy Simulator with Physical Modeling for Avoidance of Collisions Between Gantry and Couch Or Patient

    SciTech Connect

    Yamanouchi, M; Arimura, H; Yuda, I

    2014-06-01

    Purpose: It is time-consuming and might cause re-planning to check couch-gantry and patient-gantry collisions on a radiotherapy machine when using couch rotations for non-coplanar beam angles. The aim of this study was to develop a computer-graphics (CG)-based radiation therapy simulator with physical modeling for avoidance of collisions between gantry and couch or patient on a radiotherapy machine. Methods: The radiation therapy simulator was three-dimensionally constructed including a radiotherapy machine (Clinac iX, Varian Medical Systems), couch, and radiation treatment room according to their designs by using a physical-modeling-based computer graphics software (Blender, free and open-source). Each patient was modeled by applying a surface rendering technique to their planning computed tomography (CT) images acquired from 16-slice CT scanner (BrightSpeed, GE Healthcare). Immobilization devices for patients were scanned by the CT equipment, and were rendered as the patient planning CT images. The errors in the collision angle of the gantry with the couch or patient between gold standards and the estimated values were obtained by fixing the gantry angle for the evaluation of the proposed simulator. Results: The average error of estimated collision angles to the couch head side was -8.5% for gantry angles of 60 to 135 degree, and -5.5% for gantry angles of 225 to 300 degree. Moreover, the average error of estimated collision angles to the couch foot side was -1.1% for gantry angles of 60 to 135 degree, and 1.4% for gantry angles of 225 to 300 degree. Conclusion: The CG-based radiation therapy simulator could make it possible to estimate the collision angle between gantry and couch or patient on the radiotherapy machine without verifying the collision angles in the radiation treatment room.

  7. SU-E-T-480: Radiobiological Dose Comparison of Single Fraction SRS, Multi-Fraction SRT and Multi-Stage SRS of Large Target Volumes Using the Linear-Quadratic Formula

    SciTech Connect

    Ding, C; Hrycushko, B; Jiang, S; Meyer, J; Timmerman, R

    2014-06-01

    Purpose: To compare the radiobiological effect on large tumors and surrounding normal tissues from single fraction SRS, multi-fractionated SRT, and multi-staged SRS treatment. Methods: An anthropomorphic head phantom with a centrally located large volume target (18.2 cm{sup 3}) was scanned using a 16 slice large bore CT simulator. Scans were imported to the Multiplan treatment planning system where a total prescription dose of 20Gy was used for a single, three staged and three fractionated treatment. Cyber Knife treatment plans were inversely optimized for the target volume to achieve at least 95% coverage of the prescription dose. For the multistage plan, the target was segmented into three subtargets having similar volume and shape. Staged plans for individual subtargets were generated based on a planning technique where the beam MUs of the original plan on the total target volume are changed by weighting the MUs based on projected beam lengths within each subtarget. Dose matrices for each plan were export in DICOM format and used to calculate equivalent dose distributions in 2Gy fractions using an alpha beta ratio of 10 for the target and 3 for normal tissue. Results: Singe fraction SRS, multi-stage plan and multi-fractionated SRT plans had an average 2Gy dose equivalent to the target of 62.89Gy, 37.91Gy and 33.68Gy, respectively. The normal tissue within 12Gy physical dose region had an average 2Gy dose equivalent of 29.55Gy, 16.08Gy and 13.93Gy, respectively. Conclusion: The single fraction SRS plan had the largest predicted biological effect for the target and the surrounding normal tissue. The multi-stage treatment provided for a more potent biologically effect on target compared to the multi-fraction SRT treatments with less biological normal tissue than single-fraction SRS treatment.

  8. [Diagnostic apparatus in the shock trauma room].

    PubMed

    Beck, A; Bischoff, M; Gebhard, F; Huber-Lang, M; Kinzl, L; Schmelz, A

    2004-10-01

    Opinions vary with regard to the equipment and structural furnishings required for adequate management of the trauma patient in the dedicated shock suite. In order to assess the current situation in Germany, we conducted a survey of the 76 centers participating in the Polytrauma Registry of the DGU. Fifty-one questionnaires were returned by centers representing all levels of care. Responses revealed, for example, that not all centers possess capabilities for conventional radiography in the shock suite (7/51). Only 20 centers had a fixed table; the remaining 24 hospitals used either an image converter or a mobile X-ray unit. A dedicated ultrasound scanner was provided for the shock suite in 39 of 51 centers responding. Dedicated computed tomography scanners were provided for the shock suite in only eight centers (one dedicated trauma center, three level 3 centers, four university hospitals). All eight scanners use helical CT technology; at least three of the units are 8- or 16-slice. Of 51 shock suites, 12 are air-conditioned in compliance with sterile criteria (and are officially designated as surgical suites), while the remaining 39 are not. In acute cases, emergency surgeries can be performed in the shock suite in 37 centers, but not in the remaining 14 shock suites. According to the survey, slightly less than half of the hospitals responding are un-satisfied with the shock suite infrastructure ( n=24) and, of these, 13 centers are actively planning changes (the necessary financial resources have been guaranteed in 10 centers). Fourteen centers desire changes but do not currently have the required money. Information provided by Philips and Siemens suggests that the cost of furnishing a new shock suite ranges between 1.4 and 1.7 million euros. Responses to our survey show that a large gap remains between wishes and reality in the technical infrastructure in many shock suites in Germany.

  9. Coronary Artery Disease Risk Factors, Coronary Artery Calcification and Coronary Bypass Surgery

    PubMed Central

    Ulusoy, Fatih Rifat; Ipek, Emrah; Korkmaz, Ali Fuat; Gurler, Mehmet Yavuz; Gulbaran, Murat

    2015-01-01

    Introduction Atherosclerosis is an intimal disease which affects large and medium size arteries including aorta and carotid, coronary, cerebral and radial arteries. Calcium accumulated in the coronary arterial plaques have substantial contribution to the plaque volume. The aim of our study is to investigate the relationship between coronary artery disease (CAD) risk factors and coronary arterial calcification, and to delineate the importance of CACS in coronary artery bypass surgery. Materials and Methods The current study is retrospective and 410 patients admitted to our clinic with atypical chest pain and without known CAD were included. These individuals were evaluated by 16 slice electron beam computed tomography with suspicion of CAD and their calcium scores were calculated. Detailed demographic and medical history were obtained from all of the patients. Results In our study, we employed five different analyses using different coronary arterial calcification score (CACS) thresold levels reported in previous studies. All of the analyses, performed according to the previously defined thresold levels, showed that risk factors had strong positive relationship with CACS as mentioned in previous studies. Conclusion Coronary arterial calcification is part of the athero-sclerotic process and although it can be detected in atherosclerotic vessel, it is absent in a normal vessel. It can be concluded that the clinical scores, even they are helpful, have some limitations in a significant part of the population for cardiovascular risk determination. It is important for an anastomosis region to be noncalcified in coronary bypass surgery. In a coronary artery, it will be helpness for showing of calcific field and anostomosis spot. PMID:26155507

  10. Tumor volume measurement error using computed tomography imaging in a phase II clinical trial in lung cancer.

    PubMed

    Henschke, Claudia I; Yankelevitz, David F; Yip, Rowena; Archer, Venice; Zahlmann, Gudrun; Krishnan, Karthik; Helba, Brian; Avila, Ricardo

    2016-07-01

    To address the error introduced by computed tomography (CT) scanners when assessing volume and unidimensional measurement of solid tumors, we scanned a precision manufactured pocket phantom simultaneously with patients enrolled in a lung cancer clinical trial. Dedicated software quantified bias and random error in the [Formula: see text], and [Formula: see text] dimensions of a Teflon sphere and also quantified response evaluation criteria in solid tumors and volume measurements using both constant and adaptive thresholding. We found that underestimation bias was essentially the same for [Formula: see text], and [Formula: see text] dimensions using constant thresholding and had similar values for adaptive thresholding. The random error of these length measurements as measured by the standard deviation and coefficient of variation was 0.10 mm (0.65), 0.11 mm (0.71), and 0.59 mm (3.75) for constant thresholding and 0.08 mm (0.51), 0.09 mm (0.56), and 0.58 mm (3.68) for adaptive thresholding, respectively. For random error, however, [Formula: see text] lengths had at least a fivefold higher standard deviation and coefficient of variation than [Formula: see text] and [Formula: see text]. Observed [Formula: see text]-dimension error was especially high for some 8 and 16 slice CT models. Error in CT image formation, in particular, for models with low numbers of detector rows, may be large enough to be misinterpreted as representing either treatment response or disease progression.

  11. A rigid motion correction method for helical computed tomography (CT)

    NASA Astrophysics Data System (ADS)

    Kim, J.-H.; Nuyts, J.; Kyme, A.; Kuncic, Z.; Fulton, R.

    2015-03-01

    We propose a method to compensate for six degree-of-freedom rigid motion in helical CT of the head. The method is demonstrated in simulations and in helical scans performed on a 16-slice CT scanner. Scans of a Hoffman brain phantom were acquired while an optical motion tracking system recorded the motion of the bed and the phantom. Motion correction was performed by restoring projection consistency using data from the motion tracking system, and reconstructing with an iterative fully 3D algorithm. Motion correction accuracy was evaluated by comparing reconstructed images with a stationary reference scan. We also investigated the effects on accuracy of tracker sampling rate, measurement jitter, interpolation of tracker measurements, and the synchronization of motion data and CT projections. After optimization of these aspects, motion corrected images corresponded remarkably closely to images of the stationary phantom with correlation and similarity coefficients both above 0.9. We performed a simulation study using volunteer head motion and found similarly that our method is capable of compensating effectively for realistic human head movements. To the best of our knowledge, this is the first practical demonstration of generalized rigid motion correction in helical CT. Its clinical value, which we have yet to explore, may be significant. For example it could reduce the necessity for repeat scans and resource-intensive anesthetic and sedation procedures in patient groups prone to motion, such as young children. It is not only applicable to dedicated CT imaging, but also to hybrid PET/CT and SPECT/CT, where it could also ensure an accurate CT image for lesion localization and attenuation correction of the functional image data.

  12. The role of computed tomography in terminal ballistic analysis.

    PubMed

    Rutty, G N; Boyce, P; Robinson, C E; Jeffery, A J; Morgan, B

    2008-01-01

    Terminal ballistics concerns the science of projectile behaviour within a target and includes wound ballistics that considers what happens when a projectile strikes a living being. A number of soft tissue ballistic simulants have been used to assess the damage to tissue caused by projectiles. Standard assessment of these materials, such as ballistic soap or ordnance gelatine, requires the block to be opened or that a mould to be made to visualize the wound track. This is time consuming and may affect the accuracy of the findings especially if the block dries and alters shape during the process. Therefore, accurate numerical analysis of the permanent or temporary cavity is limited. Computed tomography (CT) potentially offers a quicker non-invasive analysis tool for this task. Four commercially purchased ballistic glycerine soap blocks were used. Each had a single firearm discharged into it from a distance of approximately 15 cm using both gunshot and shotgun projectiles. After discharge, each block was imaged by a modern 16 slice multi-detector CT scanner and analysed using 3-D reconstruction software. Using the anterior-posterior and lateral scout views and the multi-plane reconstructed images, it was possible to visualize the temporary cavity, as well as the fragmentation and dispersal pattern of the projectiles, the distance travelled and angle of dispersal within the block of each projectile or fragment. A virtual cast of the temporary cavity can be also be made. Multi-detector CT with 3-D analysis software is shown to create a reliable permanent record of the projectile path allowing rapid analysis of different firearms and projectiles. PMID:17205351

  13. Tumor volume measurement error using computed tomography imaging in a phase II clinical trial in lung cancer.

    PubMed

    Henschke, Claudia I; Yankelevitz, David F; Yip, Rowena; Archer, Venice; Zahlmann, Gudrun; Krishnan, Karthik; Helba, Brian; Avila, Ricardo

    2016-07-01

    To address the error introduced by computed tomography (CT) scanners when assessing volume and unidimensional measurement of solid tumors, we scanned a precision manufactured pocket phantom simultaneously with patients enrolled in a lung cancer clinical trial. Dedicated software quantified bias and random error in the [Formula: see text], and [Formula: see text] dimensions of a Teflon sphere and also quantified response evaluation criteria in solid tumors and volume measurements using both constant and adaptive thresholding. We found that underestimation bias was essentially the same for [Formula: see text], and [Formula: see text] dimensions using constant thresholding and had similar values for adaptive thresholding. The random error of these length measurements as measured by the standard deviation and coefficient of variation was 0.10 mm (0.65), 0.11 mm (0.71), and 0.59 mm (3.75) for constant thresholding and 0.08 mm (0.51), 0.09 mm (0.56), and 0.58 mm (3.68) for adaptive thresholding, respectively. For random error, however, [Formula: see text] lengths had at least a fivefold higher standard deviation and coefficient of variation than [Formula: see text] and [Formula: see text]. Observed [Formula: see text]-dimension error was especially high for some 8 and 16 slice CT models. Error in CT image formation, in particular, for models with low numbers of detector rows, may be large enough to be misinterpreted as representing either treatment response or disease progression. PMID:27660808

  14. SU-E-T-344: Validation and Clinical Experience of Eclipse Electron Monte Carlo Algorithm (EMC)

    SciTech Connect

    Pokharel, S; Rana, S

    2014-06-01

    Purpose: The purpose of this study is to validate Eclipse Electron Monte Carlo (Algorithm for routine clinical uses. Methods: The PTW inhomogeneity phantom (T40037) with different combination of heterogeneous slabs has been CT-scanned with Philips Brilliance 16 slice scanner. The phantom contains blocks of Rando Alderson materials mimicking lung, Polystyrene (Tissue), PTFE (Bone) and PMAA. The phantom has 30×30×2.5 cm base plate with 2cm recesses to insert inhomogeneity. The detector systems used in this study are diode, tlds and Gafchromic EBT2 films. The diode and tlds were included in CT scans. The CT sets are transferred to Eclipse treatment planning system. Several plans have been created with Eclipse Monte Carlo (EMC) algorithm 11.0.21. Measurements have been carried out in Varian TrueBeam machine for energy from 6–22mev. Results: The measured and calculated doses agreed very well for tissue like media. The agreement was reasonably okay for the presence of lung inhomogeneity. The point dose agreement was within 3.5% and Gamma passing rate at 3%/3mm was greater than 93% except for 6Mev(85%). The disagreement can reach as high as 10% in the presence of bone inhomogeneity. This is due to eclipse reporting dose to the medium as opposed to the dose to the water as in conventional calculation engines. Conclusion: Care must be taken when using Varian Eclipse EMC algorithm for dose calculation for routine clinical uses. The algorithm dose not report dose to water in which most of the clinical experiences are based on rather it just reports dose to medium directly. In the presence of inhomogeneity such as bone, the dose discrepancy can be as high as 10% or even more depending on the location of normalization point or volume. As Radiation oncology as an empirical science, care must be taken before using EMC reported monitor units for clinical uses.

  15. The role of computed tomography in terminal ballistic analysis.

    PubMed

    Rutty, G N; Boyce, P; Robinson, C E; Jeffery, A J; Morgan, B

    2008-01-01

    Terminal ballistics concerns the science of projectile behaviour within a target and includes wound ballistics that considers what happens when a projectile strikes a living being. A number of soft tissue ballistic simulants have been used to assess the damage to tissue caused by projectiles. Standard assessment of these materials, such as ballistic soap or ordnance gelatine, requires the block to be opened or that a mould to be made to visualize the wound track. This is time consuming and may affect the accuracy of the findings especially if the block dries and alters shape during the process. Therefore, accurate numerical analysis of the permanent or temporary cavity is limited. Computed tomography (CT) potentially offers a quicker non-invasive analysis tool for this task. Four commercially purchased ballistic glycerine soap blocks were used. Each had a single firearm discharged into it from a distance of approximately 15 cm using both gunshot and shotgun projectiles. After discharge, each block was imaged by a modern 16 slice multi-detector CT scanner and analysed using 3-D reconstruction software. Using the anterior-posterior and lateral scout views and the multi-plane reconstructed images, it was possible to visualize the temporary cavity, as well as the fragmentation and dispersal pattern of the projectiles, the distance travelled and angle of dispersal within the block of each projectile or fragment. A virtual cast of the temporary cavity can be also be made. Multi-detector CT with 3-D analysis software is shown to create a reliable permanent record of the projectile path allowing rapid analysis of different firearms and projectiles.

  16. To study tumor motion and planning target volume margins using four dimensional computed tomography for cancer of the thorax and abdomen regions.

    PubMed

    Deshpande, Sudesh

    2011-01-01

    In this study, four dimensional computed tomography (4DCT) scanning was performed during free breathing on a 16-slice Positron emission tomography PET /computed tomography (CT) for abdomen and thoracic patients. Images were sorted into 10 phases based on the temporal correlation between surface motion and data acquisition with an Advantage Workstation. Gross tumor volume gross tumor volume (GTV) s were manually contoured on all 10 phases of the 4DCT scan. GTVs in the multiple CT phases were called GTV4D. GTV4D plus an isotropic margin of 1.0 cm was called CTV4D. Two sets of planning target volume (PTV) 4D (PTV4D) were derived from the CTV4D, i.e. PTV4D(2cm) = CTV4D plus 1 cm setup margin (SM) and 1 cm internal margin (IM) and PTV4D(1.5cm) = CTV4D plus 1 cm SM and 0.5cm IM. PTV3D was derived from a CTV3D of the helical CT scan plus conventional margins of 2 cm. PTV(gated) was generated only selecting three CT phases, with a total margin of 1.5 cm. All four volumes were compared. To quantify the extent of the motion, we selected the two phases where the tumor exhibited the greatest range of motion. We also studied the effect of different PTV volumes on dose to the surrounding critical structures. Volume of CTV4D was greater than that of CTV3D. We found, on an average, a reduction of 14% volume of PTV4D(1.5cm) as compared with PTV3D and reduction of 10% volume of PTV(gated) as compared with PTV4D(1.5cm). We found that 2 cm of margin was inadequate if true motion of tumor was not known. We observed greater sparing of critical structures for PTVs drawn taking into account the tumor motion.

  17. Improving 18F-Fluoro-D-Glucose-Positron Emission Tomography/Computed Tomography Imaging in Alzheimer's Disease Studies

    PubMed Central

    Knešaurek, Karin

    2015-01-01

    The goal was to improve Alzheimer's 2-deoxy-2-18F-fluoro-D-glucose (18F FDG)-positron emission tomography (PET)/computed tomography (CT) imaging through application of a novel, hybrid Fourier-wavelet windowed Fourier transform (WFT) restoration technique, in order to provide earlier and more accurate clinical results. General Electric Medical Systems downward-looking sonar PET/CT 16 slice system was used to acquire studies. Patient data were acquired according the Alzheimer's disease Neuroimaging Initiative (ADNI) protocol. Here, we implemented Fourier-wavelet regularized restoration, with a Butterworth low-pass filter, order n = 6 and a cut-off frequency f = 0.35 cycles/pixel and wavelet (Daubechies, order 2) noise suppression. The original (PET-O) and restored (PET-R) ADNI subject PET images were compared using the Alzheimer's discrimination analysis by dedicated software. Forty-two PET/CT scans were used in the study. They were performed on eleven ADNI subjects at intervals of approximately 6 months. The final clinical diagnosis was used as a gold standard. For three subjects, the final clinical diagnosis was mild cognitive impairment and those 13 PET/CT studies were not included in the final comparison, as the result was considered as inconclusive. Using the reminding 29 PET/CT studies (23 AD and 6 normal), the sensitivity and specificity of the PET-O and PET-R were calculated. The sensitivity was 0.65 and 0.96 for PET-O and PET-R, respectively, and the specificity was 0.67 and 0.50 for PET-O and PET-R. The accuracy was 0.66 and 0.86 for PET-O and PET-R, respectively. The results of the study demonstrated that the accuracy of three-dimensional brain F-18 FDG PET images was significantly improved by Fourier-wavelet restoration filtering. PMID:26420987

  18. Improving (18)F-Fluoro-D-Glucose-Positron Emission Tomography/Computed Tomography Imaging in Alzheimer's Disease Studies.

    PubMed

    Knešaurek, Karin

    2015-01-01

    The goal was to improve Alzheimer's 2-deoxy-2-(18)F-fluoro-D-glucose ((18)F FDG)-positron emission tomography (PET)/computed tomography (CT) imaging through application of a novel, hybrid Fourier-wavelet windowed Fourier transform (WFT) restoration technique, in order to provide earlier and more accurate clinical results. General Electric Medical Systems downward-looking sonar PET/CT 16 slice system was used to acquire studies. Patient data were acquired according the Alzheimer's disease Neuroimaging Initiative (ADNI) protocol. Here, we implemented Fourier-wavelet regularized restoration, with a Butterworth low-pass filter, order n = 6 and a cut-off frequency f = 0.35 cycles/pixel and wavelet (Daubechies, order 2) noise suppression. The original (PET-O) and restored (PET-R) ADNI subject PET images were compared using the Alzheimer's discrimination analysis by dedicated software. Forty-two PET/CT scans were used in the study. They were performed on eleven ADNI subjects at intervals of approximately 6 months. The final clinical diagnosis was used as a gold standard. For three subjects, the final clinical diagnosis was mild cognitive impairment and those 13 PET/CT studies were not included in the final comparison, as the result was considered as inconclusive. Using the reminding 29 PET/CT studies (23 AD and 6 normal), the sensitivity and specificity of the PET-O and PET-R were calculated. The sensitivity was 0.65 and 0.96 for PET-O and PET-R, respectively, and the specificity was 0.67 and 0.50 for PET-O and PET-R. The accuracy was 0.66 and 0.86 for PET-O and PET-R, respectively. The results of the study demonstrated that the accuracy of three-dimensional brain F-18 FDG PET images was significantly improved by Fourier-wavelet restoration filtering.

  19. SU-E-I-25: Determining Tube Current, Tube Voltage and Pitch Suitable for Low- Dose Lung Screening CT

    SciTech Connect

    Williams, K; Matthews, K

    2014-06-01

    Purpose: The quality of a computed tomography (CT) image and the dose delivered during its acquisition depend upon the acquisition parameters used. Tube current, tube voltage, and pitch are acquisition parameters that potentially affect image quality and dose. This study investigated physicians' abilities to characterize small, solid nodules in low-dose CT images for combinations of current, voltage and pitch, for three CT scanner models. Methods: Lung CT images was acquired of a Data Spectrum anthropomorphic torso phantom with various combinations of pitch, tube current, and tube voltage; this phantom was used because acrylic beads of various sizes could be placed within the lung compartments to simulate nodules. The phantom was imaged on two 16-slice scanners and a 64-slice scanner. The acquisition parameters spanned a range of estimated CTDI levels; the CTDI estimates from the acquisition software were verified by measurement. Several experienced radiologists viewed the phantom lung CT images and noted nodule location, size and shape, as well as the acceptability of overall image quality. Results: Image quality for assessment of nodules was deemed unsatisfactory for all scanners at 80 kV (any tube current) and at 35 mA (any tube voltage). Tube current of 50 mA or more at 120 kV resulted in similar assessments from all three scanners. Physician-measured sphere diameters were closer to actual diameters for larger spheres, higher tube current, and higher kV. Pitch influenced size measurements less for larger spheres than for smaller spheres. CTDI was typically overestimated by the scanner software compared to measurement. Conclusion: Based on this survey of acquisition parameters, a low-dose CT protocol of 120 kV, 50 mA, and pitch of 1.4 is recommended to balance patient dose and acceptable image quality. For three models of scanners, this protocol resulted in estimated CTDIs from 2.9–3.6 mGy.

  20. SU-E-T-70: Commissioning a Multislice CT Scanner for X-Ray CT Polymer Gel Dosimetry

    SciTech Connect

    Johnston, H; Hilts, M; Jirasek, A

    2014-06-01

    Purpose: To commission a multislice computed tomography (CT) scanner for fast and reliable readout of radiation therapy (RT) dose distributions using CT polymer gel dosimetry (PGD). Methods: Commissioning was performed for a 16-slice CT scanner using images acquired through a 1L cylinder filled with water. Additional images were collected using a single slice machine for comparison purposes. The variability in CT number associated with the anode heel effect was evaluated and used to define a new slice-by-slice background image subtraction technique. Image quality was assessed for the multislice system by comparing image noise and uniformity to that of the single slice machine. The consistency in CT number across slices acquired simultaneously using the multislice detector array was also evaluated. Finally, the variability in CT number due to increasing x-ray tube load was measured for the multislice scanner and compared to the tube load effects observed on the single slice machine. Results: Slice-by-slice background subtraction effectively removes the variability in CT number across images acquired simultaneously using the multislice scanner and is the recommended background subtraction method when using a multislice CT system. Image quality for the multislice machine was found to be comparable to that of the single slice scanner. Further study showed CT number was consistent across image slices acquired simultaneously using the multislice detector array for each detector configuration of the slice thickness examined. In addition, the multislice system was found to eliminate variations in CT number due to increasing x-ray tube load and reduce scanning time by a factor of 4 when compared to imaging a large volume using a single slice scanner. Conclusion: A multislice CT scanner has been commissioning for CT PGD, allowing images of an entire dose distribution to be acquired in a matter of minutes. Funding support provided by the Natural Sciences and Engineering

  1. Operator eye doses during computed tomography fluoroscopic lung biopsy.

    PubMed

    Ekpo, Ernest U; Bakhshi, Suleman; Ryan, Elaine; Hogg, Peter; McEntee, Mark F

    2016-06-01

    The aim of this work was to examine the peak entrance surface air kerma (peak ESAK) to the eyes during CT fluoroscopy lung biopsy, and the impact of lead glasses, exposure parameters, head rotation, and height on peak ESAK to the eyes. Two phantoms simulating the patient and radiologist were used, and 108 exposures were made using a 16-slice Toshiba Alexion CT scanner (Toshiba Medical Systems, Nasu, Japan). ESAK to the phantom radiologist's right eye was measured using an Unfors Xi dosimeter (RaySafe, Billdal, Sweden) with and without lead glasses at two kilovoltages (120 kVp and 135 kVp) and three milliampere settings (10 mA, 20 mA, and 30 mA. A paired t test was used to compare peak ESAK to the eye at different angles, heights, and kVp and mA with and without lead glasses. Peak ESAK was higher without compared to with lead glasses (p  ⩽  0.001). The peak ESAK to the eyes increased as the phantom radiologist rotated toward the gantry without lead glasses, from 2.42 μGy at 120° to 10.54 μGy at 30° (p  =  0.001). No significant difference was noted in peak ESAK with change in phantom radiologist height (p  >  0.05). An increase from 120 kVp to 135 kVp resulted in 23% and 26% increases in peak ESAK with and without lead glasses respectively (p  =  0.001). An increase of tube current from 10 mA to 20 mA almost doubled peak ESAK (p  =  0.005). Findings demonstrate that lead glasses reduce ESAK to the eyes, and that increased kVp, mA, and eye rotation to the gantry increase ESAK to the eyes. PMID:27250649

  2. SU-E-T-541: Measurement of CT Density Model Variations and the Impact On the Accuracy of Monte Carlo (MC) Dose Calculation in Stereotactic Body Radiation Therapy for Lung Cancer

    SciTech Connect

    Xiang, H; Li, B; Behrman, R; Russo, G; Kachnic, L; Lu, H; Fernando, H

    2015-06-15

    Purpose: To measure the CT density model variations between different CT scanners used for treatment planning and impact on the accuracy of MC dose calculation in lung SBRT. Methods: A Gammex electron density phantom (RMI 465) was scanned on two 64-slice CT scanners (GE LightSpeed VCT64) and a 16-slice CT (Philips Brilliance Big Bore CT). All three scanners had been used to acquire CT for CyberKnife lung SBRT treatment planning. To minimize the influences of beam hardening and scatter for improving reproducibility, three scans were acquired with the phantom rotated 120° between scans. The mean CT HU of each density insert, averaged over the three scans, was used to build the CT density models. For 14 patient plans, repeat MC dose calculations were performed by using the scanner-specific CT density models and compared to a baseline CT density model in the base plans. All dose re-calculations were done using the same plan beam configurations and MUs. Comparisons of dosimetric parameters included PTV volume covered by prescription dose, mean PTV dose, V5 and V20 for lungs, and the maximum dose to the closest critical organ. Results: Up to 50.7 HU variations in CT density models were observed over the baseline CT density model. For 14 patient plans examined, maximum differences in MC dose re-calculations were less than 2% in 71.4% of the cases, less than 5% in 85.7% of the cases, and 5–10% for 14.3% of the cases. As all the base plans well exceeded the clinical objectives of target coverage and OAR sparing, none of the observed differences led to clinically significant concerns. Conclusion: Marked variations of CT density models were observed for three different CT scanners. Though the differences can cause up to 5–10% differences in MC dose calculations, it was found that they caused no clinically significant concerns.

  3. SU-E-I-98: Dose Comparison for Pulmonary Embolism CT Studies: Single Energy Vs. Dual Energy

    SciTech Connect

    Mahmood, U; Erdi, Y

    2014-06-01

    Purpose: The purpose of this study was to assess and compare the size specific dose estimate (SSDE), dose length product (DLP) and noise relationship for pulmonary embolism studies evaluated by single source dual energy computed tomography (DECT) against conventional CT (CCT) studies in a busy cancer center and to determine the dose savings provided by DECT. Methods: An IRB-approved retrospective study was performed to determine the CTDIvol and DLP from a subset of patients scanned with both DECT and CCT over the past five years. We were able to identify 30 breast cancer patients (6 male, 24 female, age range 24 to 81) who had both DECT and CCT studies performed. DECT scans were performed with a GE HD 750 scanner (140/80 kVp, 480 mAs and 40 mm) and CCT scans were performed with a GE Lightspeed 16 slice scanner (120 kVp, 352 mAs, 20 mm). Image noise was measured by placing an ROI and recording the standard deviation of the mean HU along the descending aorta. Results: The average DECT patient size specific dose estimate was to be 14.2 ± 1.7 mGy as compared to 22.4 ± 2.7 mGy from CCT PE studies, which is a 37% reduction in the SSDE. The average DECT DLP was 721.8 ± 84.6 mGy-cm as compared to 981.8 ± 106.1 mGy-cm for CCT, which is a 26% decrease. Compared to CCT the image noise was found to decrease by 19% when using DECT for PE studies. Conclusion: DECT SSDE and DLP measurements indicate dose savings and image noise reduction when compared to CCT. In an environment that heavily debates CT patient doses, this study confirms the effectiveness of DECT in PE imaging.

  4. Development of a Radiation Dose Reporting Software for X-ray Computed Tomography (CT)

    NASA Astrophysics Data System (ADS)

    Ding, Aiping

    X-ray computed tomography (CT) has experienced tremendous technological advances in recent years and has established itself as one of the most popular diagnostic imaging tools. While CT imaging clearly plays an invaluable role in modern medicine, its rapid adoption has resulted in a dramatic increase in the average medical radiation exposure to the worldwide and United States populations. Existing software tools for CT dose estimation and reporting are mostly based on patient phantoms that contain overly simplified anatomies insufficient in meeting the current and future needs. This dissertation describes the development of an easy-to-use software platform, “VirtualDose”, as a service to estimate and report the organ dose and effective dose values for patients undergoing the CT examinations. “VirtualDose” incorporates advanced models for the adult male and female, pregnant women, and children. To cover a large portion of the ignored obese patients that frequents the radiology clinics, a new set of obese male and female phantoms are also developed and applied to study the effects of the fat tissues on the CT radiation dose. Multi-detector CT scanners (MDCT) and clinical protocols, as well as the most recent effective dose algorithms from the International Commission on Radiological Protection (ICRP) Publication 103 are adopted in “VirtualDose” to keep pace with the MDCT development and regulatory requirements. A new MDCT scanner model with both body and head bowtie filter is developed to cover both the head and body scanning modes. This model was validated through the clinical measurements. A comprehensive slice-by-slice database is established by deriving the data from a larger number of single axial scans simulated on the patient phantoms using different CT bowtie filters, beam thicknesses, and different tube voltages in the Monte Carlo N-Particle Extended (MCNPX) code. When compared to the existing CT dose software packages, organ dose data in this

  5. Risk factors for the need of hip arthroscopy following periacetabular osteotomy

    PubMed Central

    Hartig-Andreasen, Charlotte; Troelsen, Anders; Thillemann, Theis M.; Gelineck, John; Søballe, Kjeld

    2015-01-01

    Despite the frequency of labral tears in symptomatic developmental dysplasia of the hip, no consensus exists regarding the treatment of coexisting dysplasia of the hip and tearing of the acetabular labrum. The purpose of this prospective, MR arthrography (MRA) based 2-year follow-up study was to identify risk factors predicting the need for a hip arthroscopy (HA) after periacetabular osteotomy (PAO). Ninety-nine patients (104 hips) scheduled for PAO were evaluated preoperatively and at 2-year follow-up. MRA was performed in all patients prior to PAO. At follow-up, patients were divided into a non-arthroscopy and arthroscopy group. The two groups were compared clinical and radiological, and risk factors for HA after PAO were calculated. Patient reported outcome measures (WOMAC, Oxford Hip and SF36) were filled out before PAO and at follow-up. Ninety-five hips (91.3%) were evaluated. Twenty-six hips (27%) required an arthroscopy within 2 years of the PAO. Risk factors were preoperative borderline dysplasia, acetabular retroversion and complete labral detachment. Labral tearing, degeneration or hypertrophy did not negatively affect the outcome of PAO. Patients not requiring an arthroscopy had a statistically significant better outcome measured by patients reported outcome measures. After PAO, 27% of the hips needed intra-articular assessment. Conventional radiographs and MRA analysis can be used to identify predictors for patients requiring HA after PAO. At 2-year follow-up, the clinical outcome improved in all patients. However, those patients who had no need of a HA after their PAO had superior results. PMID:27011862

  6. Treatment of unstable osteochondritis dissecans in adults with autogenous osteochondral grafts (Mosaicplasty): long-term results

    PubMed Central

    RONGA, MARIO; STISSI, PLACIDO; LA BARBERA, GIUSEPPE; VALOROSO, MARCO; ANGERETTI, GLORIA; GENOVESE, EUGENIO; CHERUBINO, PAOLO

    2015-01-01

    Purpose the unstable osteochondritis dissecans (OCD-type II and III according to the ICRS classification) of the knee largher than > 2.5 cm2 in adults are uncommon lesions and there is no consensus on how to treat them. Medium-term studies have reported good results using autogenous osteochondral plugs (mosaicplasty). The aim of this study is to analyze the long-term results of this technique for the treatment of unstable OCD in a selected group of adult patients. Methods four patients with OCD at either one of the femoral condyles were included in this prospective study. The average age was 21.2 years (range, 18–24 years). The OCD lesions were classified as type II in three patients and type III in one patient and the average size was 3.8 cm2 (range, 2.55–5.1 cm2). The lesions were treated in situ with a variable number of autogenous osteochondral plugs (Ø 4.5 mm2). The Modified Cincinnati, Lysholm II and Tegner scores were used for clinical and functional evaluation. Magnetic resonance arthrography (MRA) was performed before surgery and at 2, 5 and 10 years after surgery. A modified MOCART score was used to evaluate MRA findings. Results the average follow-up duration was ten years and 6 months (range, 10–11 years). No complications occurred. At the final follow-up, all scores (clinical, functional and MOCART) improved. In all but one of the patients MRA showed complete osteochondral repair. Conclusions the fixation of large and unstable OCD lesions with mosaicplasty may be a good option for treating type II or III OCD lesions in adults. The advantages of this technique include stable fixation, promotion of blood supply to the base of the OCD fragment, and grafting of autologous cancellous bone that stimulates healing with preservation of the articular surface. Level of evidence Level IV, therapeutic case series. PMID:26904522

  7. [Examination of the knee joint. The value of clinical findings in arthroscopic control].

    PubMed

    Steinbrück, K; Wiehmann, J C

    1988-01-01

    Purely clinical examination of the knee joint can, at best, only be regarded as a "screening procedure". Diagnosis with the aid of apparatus (sonography, arthrography, CT, NMR) produces better results. However, arthroscopy performed by an experienced examiner confirms the diagnosis in cases of suspected meniscus injury or isolated lesions of the cruciate ligaments and leads to early and therefore optimal therapy. In a retrospective study 300 arthroscopies performed in 1985 were selected and evaluated. In 1986/87, a further 300 patients were clinically examined prospectively, according to the same criteria, and findings were compared with the arthroscopy performed the following day. Clinically, in 287 patients with multiple diagnoses, internal meniscus lesions were diagnosed in 162 cases (54%), external meniscus lesions in 38 (13%), chondropathia patellae in 54 (18%), and old ruptures of the cruciate ligaments in 46 (15%). In 13 patients no diagnosis could be established. Arthroscopically, pathology of the internal meniscus was found in 98 (33%) of the 300 patients, of the external meniscus in 40 (13%), cartilage damage in 103 (34%), old cruciate ligament ruptures in 51 (17%), and recent anterior cruciate ligament ruptures in 156 (52%); in 40 cases findings were normal. At 78%, the highest positive predictive value (proportion of tentative clinical diagnoses confirmed by arthroscopy) was found in cases of old ruptures of the anterior cruciate ligament, followed by external meniscus lesions (61%) and internal meniscus lesions (55%); i.e., only 55 out of 100 clinically suspected internal meniscus lesions are diagnosed by arthroscopy.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Contrast enhanced cartilage imaging: Comparison of ionic and non-ionic contrast agents.

    PubMed

    Wiener, Edzard; Woertler, Klaus; Weirich, Gregor; Rummeny, Ernst J; Settles, Marcus

    2007-07-01

    Our objective was to compare relaxation effects, dynamics and spatial distributions of ionic and non-ionic contrast agents in articular cartilage at concentrations typically used for direct MR arthrography at 1.5T. Dynamic MR-studies over 11h were performed in 15 bovine patella specimens. For each of the contrast agents gadopentetate dimeglumine, gadobenate dimeglumine, gadoteridol and mangafodipir trinatrium three patellae were placed in 2.5mmol/L contrast solution. Simultaneous measurements of T(1) and T(2) were performed every 30min using a high-spatial-resolution "MIX"-sequence. T(1), T(2) and DeltaR(1), DeltaR(2) profile plots across cartilage thickness were calculated to demonstrate the spatial and temporal distributions. The charge is one of the main factors which controls the amount of the contrast media diffusing into intact cartilage, but independent of the charge, the spatial distribution across cartilage thickness remains highly inhomogeneous even after 11h of diffusion. The absolute DeltaR(2)-effect in cartilage is at least as large as the DeltaR(1)-effect for all contrast agents. Maximum changes were 5-12s(-1) for DeltaR(1) and 8-15s(-1) for DeltaR(2). This study indicates that for morphologically intact cartilage only the amount of contrast agents within cartilage is determined by the charge but not the spatial distribution across cartilage thickness. In addition, DeltaR(2) can be considered for quantification of contrast agent concentrations, since it is of the same magnitude and less time consuming to measure than DeltaR(1).

  9. Epidemiology and imaging of the subchondral bone in articular cartilage repair.

    PubMed

    Menetrey, Jacques; Unno-Veith, Florence; Madry, Henning; Van Breuseghem, Iwan

    2010-04-01

    Articular cartilage and the subchondral bone act as a functional unit. Following trauma, osteochondritis dissecans, osteonecrosis or osteoarthritis, this intimate connection may become disrupted. Osteochondral defects-the type of defects that extend into the subchondral bone-account for about 5% of all articular cartilage lesions. They are very often caused by trauma, in about one-third of the cases by osteoarthritis and rarely by osteochondritis dissecans. Osteochondral defects are predominantly located on the medial femoral condyle and also on the patella. Frequently, they are associated with lesions of the menisci or the anterior cruciate ligament. Because of the close relationship between the articular cartilage and the subchondral bone, imaging of cartilage defects or cartilage repair should also focus on the subchondral bone. Magnetic resonance imaging is currently considered to be the key modality for the evaluation of cartilage and underlying subchondral bone. However, the choice of imaging technique also depends on the nature of the disease that caused the subchondral bone lesion. For example, radiography is still the golden standard for imaging features of osteoarthritis. Bone scintigraphy is one of the most valuable techniques for early diagnosis of spontaneous osteonecrosis about the knee. A CT scan is a useful technique to rule out a possible depression of the subchondral bone plate, whereas a CT arthrography is highly accurate to evaluate the stability of the osteochondral fragment in osteochondritis dissecans. Particularly for the problem of subchondral bone lesions, image evaluation methods need to be refined for adequate and reproducible analysis. This article highlights recent studies on the epidemiology and imaging of the subchondral bone, with an emphasis on magnetic resonance imaging.

  10. Patterns of Age-Associated Degeneration Differ in Shoulder Muscles

    PubMed Central

    Raz, Yotam; Henseler, Jan F.; Kolk, Arjen; Riaz, Muhammad; van der Zwaal, Peer; Nagels, Jochem; Nelissen, Rob G. H. H.; Raz, Vered

    2015-01-01

    Shoulder complaints are common in the elderly and hamper daily functioning. These complaints are often caused by tears in the muscle-tendon units of the rotator cuff (RC). The four RC muscles stabilize the shoulder joint. While some RC muscles are frequently torn in shoulder complaints others remain intact. The pathological changes in RC muscles are poorly understood. We investigated changes in RC muscle pathology combining radiological and histological procedures. We measured cross sectional area (CSA) and fatty infiltration from Magnetic Resonance Imaging with Arthrography (MRA) in subjects without (N = 294) and with (N = 109) RC-tears. Normalized muscle CSA of the four RC muscles and the deltoid shoulder muscle were compared and age-associated patterns of muscle atrophy and fatty infiltration were constructed. We identified two distinct age-associated patterns: in the supraspinatus and subscapularis RC muscles CSAs continuously declined throughout adulthood, whereas in the infraspinatus and deltoid reduced CSA was prominent from midlife onwards. In the teres minor, CSA was unchanged with age. Most importantly, age-associated patterns were highly similar between subjects without RC tear and those with RC-tears. This suggests that extensive RC muscle atrophy during aging could contribute to RC pathology. We compared muscle pathology between torn infraspinatus and non-torn teres minor and the deltoid in two patients with a massive RC-tear. In the torn infraspinatus we found pronounced fatty droplets, an increase in extracellular collagen-1, a loss of myosin heavy chain-1 expression in myofibers and an increase in Pax7-positive cells. However, the adjacent intact teres minor and deltoid exhibited healthy muscle features. This suggests that satellite cells and the extracellular matrix may contribute to extensive muscle fibrosis in torn RC. We suggest that torn RC muscles display hallmarks of muscle aging whereas the teres minor could represent an aging

  11. [Diagnosis of periprosthetic hip infections].

    PubMed

    Lüdemann, C M; Schütze, N; Rudert, M

    2015-06-01

    The diagnosis of periprosthetic infection requires a clear definition itself and structured procedure concerning anamnesis, clinical examination, laboratory findings, puncture and imaging diagnostics. The clinical presentation may vary considerable due to the time of their occurrence as early, delayed, or late infection. Recognition of risk factors and knowledge of differential diagnoses facilitate and confirm the diagnosis. The synovial fluid is assessed with regard to leukocyte count, protein content, and glucose. Intraoperative tissue specimen sampling has to be performed correctly; the histopathological and microbiological studies must be assessed using specific criteria. The examination and classification of periprosthetic membranes make discrimination of the causal pathological mechanism possible, especially distinction between septic and aseptic loosening. In this manner statements with regard to etiology and prosthesis durability are possible. Different causative microorganisms appear postoperatively at specific times. Pathogens that grow as biofilms are of great significance, as they may compound diagnosis and therapy. Early infections are often caused by virulent microorganisms (S. aureus) with acute onset. Delayed (low grade) infections are usually caused by less virulent microorganisms, such as S. epidermidis or coagulase-negative staphylococci. Many diagnostic imaging methods have been used in the assessment of periprosthetic infection: plain radiographs, arthrography, ultrasonography, computed tomography, and magnetic resonance imaging. Nuclear medicine with bone scintigraphy or positron-emission tomography enhance diagnostic capabilities. Cultures of samples obtained by sonication of prostheses are more sensitive than conventional periprosthetic tissue culture. Multiplex PCR of sonication fluid is a promising test for diagnosis of periprosthetic joint infection. The promising diagnostic accuracy for interleukin-6 and procalcitonin has yet not been

  12. Clinical Outcomes of Conservative Treatment and Arthroscopic Repair of Rotator Cuff Tears: A Retrospective Observational Study

    PubMed Central

    Lee, Woo Hyung; Do, Hyun Kyung; Lee, Joong Hoon; Kim, Bo Ram; Noh, Jee Hyun; Choi, Soo Hyun; Chung, Sun Gun; Lee, Shi-Uk; Choi, Ji Eun; Kim, Seihee; Kim, Min Jee

    2016-01-01

    Objective To compare the clinical outcomes following conservative treatment and arthroscopic repair in patients with a rotator cuff tear. Methods In this retrospective study, patients aged >50 years with a symptomatic rotator cuff tear were reviewed. The rotator cuff tendons were evaluated using ultrasonography, shoulder magnetic resonance imaging or MR arthrography, and the patients with either a high-grade partial-thickness or small-to-medium-sized (≤3 cm) full-thickness tear were included in this study. The primary outcome measures were a pain assessment score and range of motion (ROM) at 1-year follow-up. The secondary outcomes were the rate of tear progression or retear along with the rate of symptom aggravation after the treatments. Results A total of 357 patients were enrolled, including 183 patients that received conservative treatment and 174 patients who received an arthroscopic repair. The pain assessment score (p<0.001) and the ROM in forward flexion (p<0.001) were significantly improved in both groups. The ROM in internal rotation did not significantly change after conservative treatment and arthroscopic repair. The pain assessment score and ROM were not significantly different between the two groups. Retear was observed in 9.6% of patients who had an arthroscopic repair and tear progression was found in 6.7% of those who underwent conservative treatment. The proportion of aggravation for pain and ROM did not significantly differ between the two groups. Conclusion The effectiveness of conservative treatment is not inferior to arthroscopic repair for patients >50 years old with a less than medium-sized rotator cuff tear in a 1-year follow-up period. Further study is warranted to find the optimal combination of conservative treatment for a symptomatic rotator cuff tear. PMID:27152275

  13. Arthroscopic intervention in early hip disease.

    PubMed

    McCarthy, Joseph C; Lee, Jo-Ann

    2004-12-01

    Advancement in diagnostic and therapeutic applications for hip arthroscopy have dispelled previous myths about early hip disease. Arthroscopic findings have established the following facts: Acetabular labral tears do occur; acetabular chondral lesions do exist; tears are most frequently anterior and often associated with sudden twisting or pivoting motions; and labral tears often occur in association with articular cartilage lesions of the adjacent acetabulum or femoral head, and if present for years, contribute to the progression of delamination process of the chondral cartilage. Magnetic resonance arthrography represents an improvement over conventional magnetic resonance imaging, it does have limitations when compared with direct observation. Although indications for hip arthroscopy are constantly expanding, the most common indications include: labral tears, loose bodies, chondral flap lesions of the acetabular or femoral head, synovial chondromatosis, foreign body removal, and crystalline hip arthropathy (gout, pseudogout, and others). Contraindications include conditions that limit the potential for hip distraction such as joint ankylosis, dense heterotopic bone formation, considerable protrusio, or morbid obesity. Complication rates have been reported between 0.5 and 5%, most often related to distraction and include sciatic or femoral nerve palsy, avascular necrosis, and compartment syndrome. Transient peroneal or pudendal nerve effects and chondral scuffing have been associated with difficult or prolonged distraction. Meticulous consideration to patient positioning, distraction time and portal placement are essential. Judicious patient selection and diagnostic expertise are critical to successful outcomes. Candidates for hip arthroscopy should include only those patients with mechanical symptoms (catching, locking, or buckling) that have failed to respond to conservative therapy. The extent of articular cartilage involvement has the most direct relationship

  14. [The temporo-mandibular joint in pathologic conditions: rheumatoid arthritis and seronegative spondyloarthritis].

    PubMed

    Scutellari, P N; Orzincolo, C; Ceruti, S

    1993-10-01

    Pain and dysfunction of the temporomandibular joint (TMJ) are major clinical problems, especially in arthritides and allied conditions. In the last 10 years, such new imaging methods as arthrography, CT and MRI have been developed, but many problems are still to be solved. This study was aimed at reporting the radiographic patterns of lesions in TMJ rheumatoid arthritis and seronegative spondyloarthropathies and at investigating the role of conventional radiology in the assessment of these disorders. Digital hypocycloidal tomography of the TMJ was performed on 44 patients affected with rheumatoid arthritis, on 2 with Sjögren's syndrome, 2 with ankylosing spondylitis, 4 with psoriatic arthritis and 1 with Reiter's syndrome. CT, with sagittal and coronal scans, was performed only on 9 patients (18 joints) whose clinical and radiographic findings were particularly severe. The radiographic features of the lesions--i.e., erosions, osteophytes, subchondral bone sclerosis and condylar-glenoid fossa remodelling--cannot be distinguished from one another and from the so-called allied conditions; nevertheless, in rheumatoid arthritis abnormalities are usually bilateral and symmetric, whereas in seronegative arthropathies joint involvement is usually unilateral. In the first stage of the disease, these lesions are better demonstrated by CT than by tomography, thanks to better contrast and spatial resolution of the former, especially on the lateral and medial aspects of the joint. The most common findings were: erosions (68.2%), osteophytes (31.8%), subchondral bone sclerosis (28.6%) and condylar-glenoid fossa remodelling (9.1%). In the clinical practice sagittal multidirectional tomography remains today the method of choice because it can demonstrate several areas on the condylar surface, with finer anatomical detailing, and it can solve most diagnostic problems in TMJ disorders. Thus, CT is recommended only in the patients whose diagnosis remains questionable with the above

  15. Arthroscopic intervention in early hip disease.

    PubMed

    McCarthy, Joseph C; Lee, Jo-Ann

    2004-12-01

    Advancement in diagnostic and therapeutic applications for hip arthroscopy have dispelled previous myths about early hip disease. Arthroscopic findings have established the following facts: Acetabular labral tears do occur; acetabular chondral lesions do exist; tears are most frequently anterior and often associated with sudden twisting or pivoting motions; and labral tears often occur in association with articular cartilage lesions of the adjacent acetabulum or femoral head, and if present for years, contribute to the progression of delamination process of the chondral cartilage. Magnetic resonance arthrography represents an improvement over conventional magnetic resonance imaging, it does have limitations when compared with direct observation. Although indications for hip arthroscopy are constantly expanding, the most common indications include: labral tears, loose bodies, chondral flap lesions of the acetabular or femoral head, synovial chondromatosis, foreign body removal, and crystalline hip arthropathy (gout, pseudogout, and others). Contraindications include conditions that limit the potential for hip distraction such as joint ankylosis, dense heterotopic bone formation, considerable protrusio, or morbid obesity. Complication rates have been reported between 0.5 and 5%, most often related to distraction and include sciatic or femoral nerve palsy, avascular necrosis, and compartment syndrome. Transient peroneal or pudendal nerve effects and chondral scuffing have been associated with difficult or prolonged distraction. Meticulous consideration to patient positioning, distraction time and portal placement are essential. Judicious patient selection and diagnostic expertise are critical to successful outcomes. Candidates for hip arthroscopy should include only those patients with mechanical symptoms (catching, locking, or buckling) that have failed to respond to conservative therapy. The extent of articular cartilage involvement has the most direct relationship

  16. Morphological variations of residual hip dysplasia in the adult.

    PubMed

    Ganz, R; Leunig, M

    2007-01-01

    Common understanding of residual hip dysplasia of the adult characterizes it as a uniform, anterolateral insufficiency of femoral head coverage; the proximal femur may or may not have increased valgus and antetorsion. This view is reflected by the parameters used for quantification but also by the classic surgical approaches to compensate or correct the deformity. More than two decades of dedication to hip dysplasia and its surgical treatment, but also the application of modern diagnostic tools such as magnetic resonance arthrography have allowed us to portray hip dysplasia more polymorphically showing a number of additional aspects with pathophysiologic, therapeutic and prognostic valence. The rim in acetabular dysplasia shows a variety of pathomorphologies ranging from hypertrophy and tearing of the labrum including fatigue fracture of the rim to degeneration with ganglion formation within the labrum, the capsule or the acetabular bone. Such rim pathology may explain sudden onset of pain but also influences the prognosis of joint preserving surgery. It is a rather new understanding that the acetabular morphology in hip dysplasia is not uniform. Pure lateral and pure anterior deficiency of coverage are small but interesting subgroups. Together with the frequent retroversion of the acetabulum these morphological and spatial aspects require special attention for a precise individual correction of the deformity. Finally, minor morphological abnormalities of the antero-lateral head-neck junction have been found to favor impingement after correction of the acetabulum. Knowledge of this problem has prompted a routine check of internal rotation in flexion during surgery and eventual arthrotomy and osteochondroplasty of the impinging site of the head and neck junction. PMID:19197881

  17. Anterior femoroacetabular impingement: an update.

    PubMed

    Lequesne, Michel; Bellaïche, Laurence

    2012-05-01

    Anterior femoroacetabular impingement can cause early hip osteoarthritis. The typical patient is an adult younger than 50 years of age, often with a history of sporting activities. The main symptom is intermittent pain triggered by static flexion (low seats) or dynamic flexion (during sporting or occupational activities that require repeated hip flexion). The characteristic physical finding is pain triggered by placing the hip in internal rotation and 70 to 110° of flexion. In additional to anteroposterior and false-profile radiographs, lateral Dunn or Ducroquet views should be obtained on both sides to visualize the anterior part of the head-neck junction. Instead of being concave, the head-neck junction is either flat or convex, causing a cam effect that damages the labrum and anterosuperior cartilage. Non-sphericity of the femoral head with an anterior ovoid bulge induces a similar cam effect. In pincer impingement, which is less common, over-coverage by the anterosuperior acetabular rim pinches the labrum between the rim and the femoral head-neck junction when the hip is flexed. Pincer impingement is related to acetabular retroversion or protrusion. Arthrography coupled with computed tomography or magnetic resonance imaging visualizes the morphological abnormalities (e.g., ovoid shape of the femoral head or retroversion of the acetabulum) and detects secondary lesions such as labral tears or separation or damage to the anterosuperior cartilage. Arthroscopy allows removal of the damaged labrum and correction of the morphological abnormalities via femoroplasty to restore the normal concave shape of the neck and/or acetabuloplasty to eliminate over-coverage. Short- or mid-term results are satisfactory in 75 to 80% of patients. However, the presence of degenerative lesions in about two-thirds of patients at the time of arthroplastic surgery limits the probability of achieving good long-term results. PMID:22281229

  18. Patterns of Age-Associated Degeneration Differ in Shoulder Muscles.

    PubMed

    Raz, Yotam; Henseler, Jan F; Kolk, Arjen; Riaz, Muhammad; van der Zwaal, Peer; Nagels, Jochem; Nelissen, Rob G H H; Raz, Vered

    2015-01-01

    Shoulder complaints are common in the elderly and hamper daily functioning. These complaints are often caused by tears in the muscle-tendon units of the rotator cuff (RC). The four RC muscles stabilize the shoulder joint. While some RC muscles are frequently torn in shoulder complaints others remain intact. The pathological changes in RC muscles are poorly understood. We investigated changes in RC muscle pathology combining radiological and histological procedures. We measured cross sectional area (CSA) and fatty infiltration from Magnetic Resonance Imaging with Arthrography (MRA) in subjects without (N = 294) and with (N = 109) RC-tears. Normalized muscle CSA of the four RC muscles and the deltoid shoulder muscle were compared and age-associated patterns of muscle atrophy and fatty infiltration were constructed. We identified two distinct age-associated patterns: in the supraspinatus and subscapularis RC muscles CSAs continuously declined throughout adulthood, whereas in the infraspinatus and deltoid reduced CSA was prominent from midlife onwards. In the teres minor, CSA was unchanged with age. Most importantly, age-associated patterns were highly similar between subjects without RC tear and those with RC-tears. This suggests that extensive RC muscle atrophy during aging could contribute to RC pathology. We compared muscle pathology between torn infraspinatus and non-torn teres minor and the deltoid in two patients with a massive RC-tear. In the torn infraspinatus we found pronounced fatty droplets, an increase in extracellular collagen-1, a loss of myosin heavy chain-1 expression in myofibers and an increase in Pax7-positive cells. However, the adjacent intact teres minor and deltoid exhibited healthy muscle features. This suggests that satellite cells and the extracellular matrix may contribute to extensive muscle fibrosis in torn RC. We suggest that torn RC muscles display hallmarks of muscle aging whereas the teres minor could represent an aging

  19. Iodine-125 Seeds Strand for Treatment of Tumor Thrombus in Inferior Vena Cava: An Experimental Study in a Rabbit Model

    SciTech Connect

    Zhang, Wen Yan, Zhiping Luo, Jianjun Fang, Zhuting Wu, Linlin Liu, QingXin Qu, Xudong Liu, Lingxiao Wang, Jianhua

    2013-10-15

    Objective: The purpose of this study was to establish an animal model of implanted inferior vena cava tumor thrombus (IVCTT) and to evaluate the effect of linear iodine-125 seeds strand in treating implanted IVCTT. Methods: Tumor cell line VX{sub 2} was inoculated subcutaneously into New Zealand rabbit to develop the parent tumor. The tumor strip was inoculated into inferior vena cava (IVC) to establish the IVCTT model. The IVCTT was confirmed by multidetector computed tomography (MDCT) after 2 weeks. Twelve rabbits with IVCTT were randomly divided into two groups. Treatment group (group T; n = 6) underwent Iodine-125 seeds brachytherapy, and the control group (group C; n = 6) underwent blank seeds strand. The blood laboratory examination (including blood routine examination, hepatic and renal function), body weight, survival time, and IVCTT volume by MDCT were monitored. All rabbits were dissected postmortem, and the therapeutic effects were evaluated on the basis of histopathology. The proliferating cell nuclear antigen index (PI) and apoptosis index (AI) of IVCTT were compared between two groups. T test, Wilcoxon rank test, and Kaplan-Meier survival curve analysis were used. Results: The success rate of establishing IVCTT was 100 %. The body weight loss and cachexia of rabbits in group C appeared earlier than in group T. Body weight in the third week, the mean survival time, PI, AI in groups T and C were 2.23 {+-} 0.12 kg, 57.83 {+-} 8.68 days, (16.73 {+-} 5.18 %), (29.47 {+-} 7.18 %), and 2.03 {+-} 0.13 kg, 43.67 {+-} 5.28 days, (63.01 {+-} 2.01 %), (6.02 {+-} 2.93 %), respectively. There were statistically significant differences between group T and group C (P < 0.05). The IVCTT volume of group T was remarkably smaller than that of group C. Conclusions: Injecting and suspensory fixing VX2 tumor strip into IVC is a reliable method to establish IVCTT animal model. The linear Iodine-125 seeds strand brachytherapy was a safe and effective method for treating IVCTT

  20. Patient-specific dose estimation for pediatric chest CT

    SciTech Connect

    Li Xiang; Samei, Ehsan; Segars, W. Paul; Sturgeon, Gregory M.; Colsher, James G.; Frush, Donald P.

    2008-12-15

    Current methods for organ and effective dose estimations in pediatric CT are largely patient generic. Physical phantoms and computer models have only been developed for standard/limited patient sizes at discrete ages (e.g., 0, 1, 5, 10, 15 years old) and do not reflect the variability of patient anatomy and body habitus within the same size/age group. In this investigation, full-body computer models of seven pediatric patients in the same size/protocol group (weight: 11.9-18.2 kg) were created based on the patients' actual multi-detector array CT (MDCT) data. Organs and structures in the scan coverage were individually segmented. Other organs and structures were created by morphing existing adult models (developed from visible human data) to match the framework defined by the segmented organs, referencing the organ volume and anthropometry data in ICRP Publication 89. Organ and effective dose of these patients from a chest MDCT scan protocol (64 slice LightSpeed VCT scanner, 120 kVp, 70 or 75 mA, 0.4 s gantry rotation period, pitch of 1.375, 20 mm beam collimation, and small body scan field-of-view) was calculated using a Monte Carlo program previously developed and validated to simulate radiation transport in the same CT system. The seven patients had normalized effective dose of 3.7-5.3 mSv/100 mAs (coefficient of variation: 10.8%). Normalized lung dose and heart dose were 10.4-12.6 mGy/100 mAs and 11.2-13.3 mGy/100 mAs, respectively. Organ dose variations across the patients were generally small for large organs in the scan coverage (<7%), but large for small organs in the scan coverage (9%-18%) and for partially or indirectly exposed organs (11%-77%). Normalized effective dose correlated weakly with body weight (correlation coefficient: r=-0.80). Normalized lung dose and heart dose correlated strongly with mid-chest equivalent diameter (lung: r=-0.99, heart: r=-0.93); these strong correlation relationships can be used to estimate patient-specific organ dose for

  1. Image reconstruction and image quality evaluation for a 64-slice CT scanner with z-flying focal spot

    SciTech Connect

    Flohr, T.G.; Stierstorfer, K.; Ulzheimer, S.; Bruder, H.; Primak, A.N.; McCollough, C.H.

    2005-08-15

    We present a theoretical overview and a performance evaluation of a novel z-sampling technique for multidetector row CT (MDCT), relying on a periodic motion of the focal spot in the longitudinal direction (z-flying focal spot) to double the number of simultaneously acquired slices. The z-flying focal spot technique has been implemented in a recently introduced MDCT scanner. Using 32x0.6 mm collimation, this scanner acquires 64 overlapping 0.6 mm slices per rotation in its spiral (helical) mode of operation, with the goal of improved longitudinal resolution and reduction of spiral artifacts. The longitudinal sampling distance at isocenter is 0.3 mm. We discuss in detail the impact of the z-flying focal spot technique on image reconstruction. We present measurements of spiral slice sensitivity profiles (SSPs) and of longitudinal resolution, both in the isocenter and off-center. We evaluate the pitch dependence of the image noise measured in a centered 20 cm water phantom. To investigate spiral image quality we present images of an anthropomorphic thorax phantom and patient scans. The full width at half maximum (FWHM) of the spiral SSPs shows only minor variations as a function of the pitch, measured values differ by less than 0.15 mm from the nominal values 0.6, 0.75, 1, 1.5, and 2 mm. The measured FWHM of the smallest slice ranges between 0.66 and 0.68 mm at isocenter, except for pitch 0.55 (0.72 mm). In a centered z-resolution phantom, bar patterns up to 15 lp/cm can be visualized independent of the pitch, corresponding to 0.33 mm longitudinal resolution. 100 mm off-center, bar patterns up to 14 lp/cm are visible, corresponding to an object size of 0.36 mm that can be resolved in the z direction. Image noise for constant effective mAs is almost independent of the pitch. Measured values show a variation of less than 7% as a function of the pitch, which demonstrates correct utilization of the applied radiation dose at any pitch. The product of image noise and square

  2. Feasibility of Coronary Artery Wall Thickening Assessment in Asymptomatic Coronary Artery Disease using Phase-Sensitive Dual Inversion Recovery MRI at 3T

    PubMed Central

    Gharib, Ahmed M.; Zahiri, Homeira; Matta, Jatin; Pettigrew, Roderic I.; Abd-Elmoniem, Khaled Z.

    2013-01-01

    Objectives The purpose of this study is to (1) investigate the image quality of phase-sensitive dual inversion recovery (PS-DIR) coronary wall imaging in healthy subjects and in subjects with known coronary artery disease (CAD) and to (2) investigate the utilization of PS-DIR at 3T in the assessment of coronary artery thickening in subjects with asymptomatic but variable degrees of CAD. Materials and Methods A total of 37 subjects participated in this Institutional Review Board approved and HIPAA-compliant study. These included 21 subjects with known CAD as identified on Multi-Detector CT angiography (MDCT). Sixteen healthy subjects without known history of CAD were included. All subjects were scanned using free-breathing PS-DIR MRI for the assessment of coronary wall thickness at 3T. Lumen-tissue contrast-to-noise ratio (CNR), signal-to-noise (SNR), and quantitative vessel parameters including lumen area and wall thickness were measured. Statistical analyses were performed. Results PS-DIR was successfully completed in 76% of patients and in 88% of the healthy subjects. Phase-sensitive signed magnitude reconstruction, compared to modulus magnitude images, significantly improved lumen-tissue contrast-to-noise ratio (CNR) in both healthy subjects (26.73±11.95 vs. 14.65±9.57, p<0.001) and in patients (21.45±7.61 vs. 16.65±5.85, p<0.001). There was no difference in image CNR and SNR between groups. In arterial segments free of plaques, coronary wall was thicker in patients in comparison to healthy subjects (1.74±0.27mm vs. 1.17±0.14mm, p<0.001) without a change in lumen area (4.51±2.42 mm2 vs. 5.71±3.11 mm2, p=0.25). Conclusions This is the first study to demonstrate the feasibility of successfully obtaining vessel wall images at 3T using PS-DIR in asymptomatic patients with known variable degrees of CAD as detected by MDCT. This was achieved with a fixed subject-invariant planning of blood signal nulling. With that limitation alleviated, PS-DIR coronary wall

  3. Angular on-line tube current modulation in multidetector CT examinations of children and adults: The influence of different scanning parameters on dose reduction

    SciTech Connect

    Papadakis, Antonios E.; Perisinakis, Kostas; Damilakis, John

    2007-07-15

    The purpose of this study was to assess the potential of angular on-line tube current modulation on dose reduction in pediatric and adult patients undergoing multidetector computed tomography (MDCT) examinations. Five physical anthropomorphic phantoms that simulate the average individual as neonate, 1-year-old, 5-year-old, 10-year-old, and adult were employed in the current study. Phantoms were scanned with the use of on-line tube current modulation (TCM). Percent dose reduction (%DR) factors achieved by applying TCM, were determined for standard protocols used for head and neck, shoulder, thorax, thorax and abdomen, abdomen, abdomen and pelvis, pelvis, and whole body examinations. A preliminary study on the application of TCM in MDCT examinations of adult patients was performed to validate the results obtained in anthropomorphic phantoms. Dose reduction was estimated as the percentage difference of the modulated milliamperes for each scan and the preset milliamperes prescribed by the scan protocol. The dose reduction in children was found to be much lower than the corresponding reduction achieved for adults. For helical scans the %DR factors, ranged between 1.6% and 7.4% for the neonate, 2.9% and 8.7% for the 1-year old, 2% and 6% for the 5-year-old, 5% and 10.9% for the 10-year-old, and 10.4% and 20.7% for the adult individual. For sequential scans the corresponding %DR factors ranged between 1.3% and 6.7%, 4.5% and 11%, 4.2% and 6.6%, 6.4% and 12.3%, and 8.9% and 23.3%, respectively. Broader beam collimations are associated with decreased %DR factors, when other scanning parameters are held constant. TCM did not impair image noise. In adult patients, the %DR values were found to be in good agreement with the corresponding results obtained in the anthropomorphic adult phantom. In conclusion, on-line TCM may be considered as a valuable tool for reducing dose in routine CT examinations of pediatric and adult patients. However, the dose reduction achieved with TCM

  4. Multidetector CT Findings and Differential Diagnoses of Malignant Pleural Mesothelioma and Metastatic Pleural Diseases in Korea

    PubMed Central

    Kim, Yoon Kyung; Lee, Kyung Won; Yi, Chin A; Koo, Jin Mo; Jung, Soon-Hee

    2016-01-01

    Objective To compare the multidetector CT (MDCT) features of malignant pleural mesothelioma (MPM) and metastatic pleural disease (MPD). Materials and Methods The authors reviewed the MDCT images of 167 patients, 103 patients with MPM and 64 patients with MPD. All 167 cases were pathologically confirmed by sonography-guided needle biopsy of pleura, thoracoscopic pleural biopsy, or open thoracotomy. CT features were evaluated with respect to pleural effusion, pleural thickening, invasion of other organs, lung abnormality, lymphadenopathy, mediastinal shifting, thoracic volume decrease, asbestosis, and the presence of pleural plaque. Results Pleural thickening was the most common CT finding in MPM (96.1%) and MPD (93.8%). Circumferential pleural thickening (31.1% vs. 10.9%, odds ratio [OR] 3.670), thickening of fissural pleura (83.5% vs. 67.2%, OR 2.471), thickening of diaphragmatic pleura (90.3% vs. 73.4%, OR 3.364), pleural mass (38.8% vs. 23.4%, OR 2.074), pericardial involvement (56.3% vs. 20.3%, OR 5.056), and pleural plaque (66.0% vs. 21.9%, OR 6.939) were more frequently seen in MPM than in MPD. On the other hand, nodular pleural thickening (59.2% vs. 76.6%, OR 0.445), hilar lymph node metastasis (5.8% vs. 20.3%, OR 0.243), mediastinal lymph node metastasis (10.7% vs. 37.5%, OR 0.199), and hematogenous lung metastasis (9.7% vs. 29.2%, OR 0.261) were less frequent in MPM than in MPD. When we analyzed MPD from extrathoracic malignancy (EMPD) separately and compared them to MPM, circumferential pleural thickening, thickening of interlobar fissure, pericardial involvement and presence of pleural plaque were significant findings indicating MPM than EMPD. MPM had significantly lower occurrence of hematogenous lung metastasis, as compared with EMPD. Conclusion Awareness of frequent and infrequent CT findings could aid in distinguishing MPM from MPD. PMID:27390546

  5. Ten-Year Follow-Up of Endovascular Aneurysm Treatment with Talent Stent-Grafts

    SciTech Connect

    Pitton, Michael B. Scheschkowski, Tobias; Ring, Markus; Herber, Sascha; Oberholzer, Katja; Leicher-Dueber, Annegret; Neufang, Achim; Schmiedt, Walther; Dueber, Christoph

    2009-09-15

    The purpose of this study was to evaluate the clinical results, complications, and secondary interventions during long-term follow-up after endovascular aneurysm repair (EVAR) and to investigate the impact of endoleak sizes on aneurysm shrinkage. From 1997 to March 2007, 127 patients (12 female, 115 male; age, 73.0 {+-} 7.2 years) with abdominal aortic aneurysms were treated with Talent stent-grafts. Follow-up included clinical visits, contrast-enhanced MDCT, and radiographs at 3, 6, and 12 months and then annually. Results were analyzed with respect to clinical outcome, secondary interventions, endoleak rate and management, and change in aneurysm size. There was no need for primary conversion surgery. Thirty-day mortality was 1.6% (two myocardial infarctions). Procedure-related morbidity was 2.4% (paraplegia, partial infarction of one kidney, and inguinal bleeding requiring surgery). Mean follow-up was 47.7 {+-} 34.2 months (range, 0-123 months). Thirty-nine patients died during follow-up; three of the deaths were related to aneurysm (aneurysm rupture due to endoleak, n = 1; secondary surgical reintervention n = 2). During follow-up, a total of 29 secondary procedures were performed in 19 patients, including 14 percutaneous procedures (10 patients) and 15 surgical procedures (12 patients), including 4 cases with late conversion to open aortic repair (stent-graft infection, n = 1; migration, endoleak, or endotension, n = 3). Overall mean survival was 84.5 {+-} 4.7 months. Mean survival and freedom from any event was 66.7 {+-} 4.5 months. MRI depicted significantly more endoleaks compared to MDCT (23.5% vs. 14.3%; P < 0.01). Patients in whom all aneurysm side branches were occluded prior to stent-grafting showed a significantly reduced incidence of large endoleaks. Endoleaks >10% of the aneurysm area were associated with reduced aneurysm shrinkage compared to no endoleaks or <10% endoleaks ({Delta} at 3 years, -1.8% vs. -12.0%; P < 0.05). In conclusion, endovascular

  6. Assessment of sub-milli-sievert abdominal computed tomography with iterative reconstruction techniques of different vendors

    PubMed Central

    Padole, Atul; Sainani, Nisha; Lira, Diego; Khawaja, Ranish Deedar Ali; Pourjabbar, Sarvenaz; Lo Gullo, Roberto; Otrakji, Alexi; Kalra, Mannudeep K

    2016-01-01

    AIM: To assess diagnostic image quality of reduced dose (RD) abdominal computed tomography (CT) with 9 iterative reconstruction techniques (IRTs) from 4 different vendors to the standard of care (SD) CT. METHODS: In an Institutional Review Board approved study, 66 patients (mean age 60 ± 13 years, 44 men, and 22 women) undergoing routine abdomen CT on multi-detector CT (MDCT) scanners from vendors A, B, and C (≥ 64 row CT scanners) (22 patients each) gave written informed consent for acquisition of an additional RD CT series. Sinogram data of RD CT was reconstructed with two vendor-specific and a vendor-neutral IRTs (A-1, A-2, A-3; B-1, B-2, B-3; and C-1, C-2, C-3) and SD CT series with filtered back projection. Subjective image evaluation was performed by two radiologists for each SD and RD CT series blinded and independently. All RD CT series (198) were assessed first followed by SD CT series (66). Objective image noise was measured for SD and RD CT series. Data were analyzed by Wilcoxon signed rank, kappa, and analysis of variance tests. RESULTS: There were 13/50, 18/57 and 9/40 missed lesions (size 2-7 mm) on RD CT for vendor A, B, and C, respectively. Missed lesions includes liver cysts, kidney cysts and stone, gall stone, fatty liver, and pancreatitis. There were also 5, 4, and 4 pseudo lesions (size 2-3 mm) on RD CT for vendor A, B, and C, respectively. Lesions conspicuity was sufficient for clinical diagnostic performance for 6/24 (RD-A-1), 10/24 (RD-A-2), and 7/24 (RD-A-3) lesions for vendor A; 5/26 (RD-B-1), 6/26 (RD-B-2), and 7/26 (RD-B-3) lesions for vendor B; and 4/20 (RD-C-1) 6/20 (RD-C-2), and 10/20 (RD-C-3) lesions for vendor C (P = 0.9). Mean objective image noise in liver was significantly lower for RD A-1 compared to both RD A-2 and RD A-3 images (P < 0.001). Similarly, mean objective image noise lower for RD B-2 (compared to RD B-1, RD B-3) and RD C-3 (compared to RD C-1 and C-2) (P = 0.016). CONCLUSION: Regardless of IRTs and MDCT vendors

  7. Virtual assessment of perimortem and postmortem blunt force cranial trauma.

    PubMed

    Fleming-Farrell, Dara; Michailidis, Konstantinos; Karantanas, Apostolos; Roberts, Neil; Kranioti, Elena F

    2013-06-10

    The aim of this study is to investigate the potential use of reconstructed three-dimensional multi-detector computed tomography (3D MDCT) imagery to distinguish between perimortem cranial trauma and postmortem cranial damage. A total of 45 crania were initially examined for the purpose of this study. The postmortem group consists of 14 crania from a Medieval Scottish population while the perimortem group consists of 31 CT scans of perimortem trauma cases from the University Hospital of Heraklion, Crete. Six crania belonging to the perimortem group could not be assessed for the purposes of this study. Each of the remaining 39 crania was examined under the following criteria: preponderant texture, preponderant outline, edge morphology, fracture angle, fracture relationship to path of least resistance, evidence of plastic response and the presence of hinging. As edge morphology could not be determined for any of the crania this criterion was not considered for statistical computations. Statistical analysis demonstrated the five of the six criteria (preponderant texture, preponderant outline, fracture relationship to least resistance path, plastic response and the presence of hinging) subjected to statistical analysis bore statistical significance in distinguishing between perimortem trauma and postmortem damage when using 3D CT images. This study, therefore, demonstrated that the timing of cranial fractures can be determined using 3D CT images and thus can complement and add to existing methods for trauma assessment in both forensic and archaeological settings. PMID:23601150

  8. Idiopathic interstitial pneumonias and emphysema: detection and classification using a texture-discriminative approach

    NASA Astrophysics Data System (ADS)

    Fetita, C.; Chang-Chien, K. C.; Brillet, P. Y.; Pr"teux, F.; Chang, R. F.

    2012-03-01

    Our study aims at developing a computer-aided diagnosis (CAD) system for fully automatic detection and classification of pathological lung parenchyma patterns in idiopathic interstitial pneumonias (IIP) and emphysema using multi-detector computed tomography (MDCT). The proposed CAD system is based on three-dimensional (3-D) mathematical morphology, texture and fuzzy logic analysis, and can be divided into four stages: (1) a multi-resolution decomposition scheme based on a 3-D morphological filter was exploited to discriminate the lung region patterns at different analysis scales. (2) An additional spatial lung partitioning based on the lung tissue texture was introduced to reinforce the spatial separation between patterns extracted at the same resolution level in the decomposition pyramid. Then, (3) a hierarchic tree structure was exploited to describe the relationship between patterns at different resolution levels, and for each pattern, six fuzzy membership functions were established for assigning a probability of association with a normal tissue or a pathological target. Finally, (4) a decision step exploiting the fuzzy-logic assignments selects the target class of each lung pattern among the following categories: normal (N), emphysema (EM), fibrosis/honeycombing (FHC), and ground glass (GDG). According to a preliminary evaluation on an extended database, the proposed method can overcome the drawbacks of a previously developed approach and achieve higher sensitivity and specificity.

  9. Correlation of measures of regional lung ventilation from 4DCT vs. hyperpolarized helium-3 MR

    NASA Astrophysics Data System (ADS)

    Ding, Kai; Cao, Kunlin; Miller, Wilson; Christensen, Gary; Reinhardt, Joseph; Benedict, Stanley; Libby, Bruce; Sheng, Ke

    2012-03-01

    Radiation induced pulmonary diseases can change the tissue material properties of lung parenchyma and the mechanics of the respiratory system. Recent advances in multi-detector-row CT (MDCT), 4DCT respiratory gating methods, and image processing techniques enable us to follow and measure those changes noninvasively during radiation therapy at a regional level. This study compares the 4DCT based ventilation measurement with the results from hyperpolarized helium-3 MR using the cumulative distribution function maps and the relative overlap (RO) statistic. We show that the similarity between the two measurements increases as the increase of the B-Spline grid spacing and Laplacian weighting which result a smoother ventilation map. The best similarity is found with weighting of 0.5 for linear elasticity and B-Spline grid spacing of 32 mm. Future work is to improve the lung image registration algorithm by incorporating hyperpolarized helium-3 MR information so as to improve its physiological modeling of the lung tissue deformation.

  10. Using anisotropic 3D Minkowski functionals for trabecular bone characterization and biomechanical strength prediction in proximal femur specimens

    NASA Astrophysics Data System (ADS)

    Nagarajan, Mahesh B.; De, Titas; Lochmüller, Eva-Maria; Eckstein, Felix; Wismüller, Axel

    2014-04-01

    The ability of Anisotropic Minkowski Functionals (AMFs) to capture local anisotropy while evaluating topological properties of the underlying gray-level structures has been previously demonstrated. We evaluate the ability of this approach to characterize local structure properties of trabecular bone micro-architecture in ex vivo proximal femur specimens, as visualized on multi-detector CT, for purposes of biomechanical bone strength prediction. To this end, volumetric AMFs were computed locally for each voxel of volumes of interest (VOI) extracted from the femoral head of 146 specimens. The local anisotropy captured by such AMFs was quantified using a fractional anisotropy measure; the magnitude and direction of anisotropy at every pixel was stored in histograms that served as a feature vectors that characterized the VOIs. A linear multi-regression analysis algorithm was used to predict the failure load (FL) from the feature sets; the predicted FL was compared to the true FL determined through biomechanical testing. The prediction performance was measured by the root mean square error (RMSE) for each feature set. The best prediction performance was obtained from the fractional anisotropy histogram of AMF Euler Characteristic (RMSE = 1.01 ± 0.13), which was significantly better than MDCT-derived mean BMD (RMSE = 1.12 ± 0.16, p<0.05). We conclude that such anisotropic Minkowski Functionals can capture valuable information regarding regional trabecular bone quality and contribute to improved bone strength prediction, which is important for improving the clinical assessment of osteoporotic fracture risk.

  11. A computerized scheme for localization of vertebral bodies on body CT scans

    NASA Astrophysics Data System (ADS)

    Hayashi, Tatsuro; Chen, Huayue; Miyamoto, Kei; Zhou, Xiangrong; Hara, Takeshi; Yokoyama, Ryujiro; Kanematsu, Masayuki; Hoshi, Hiroaki; Fujita, Hiroshi

    2011-03-01

    The multidetector row computed tomography (MDCT) method has the potential to be used for quantitative analysis of osteoporosis with higher accuracy and precision than that provided by conventional two-dimensional methods. It is desirable to develop a computer-assisted scheme for analyzing vertebral geometry using body CT images. The aim of this study was to design a computerized scheme for the localization of vertebral bodies on body CT images. Our new scheme involves the following steps: (i) Re-formation of CT images on the basis of the center line of the spinal canal to visually remove the spinal curvature, (ii) use of information on the position of the ribs relative to the vertebral bodies, (iii) the construction of a simple model on the basis of the contour of the vertebral bodies on CT sections, and (iv) the localization of individual vertebral bodies by using a template matching technique. The proposed scheme was applied to 104 CT cases, and its performance was assessed using the Hausdorff distance. The average Hausdorff distance of T2-L5 was 4.3 mm when learning models with 100 samples were used. On the other hand, the average Hausdorff distance with 10 samples was 5.1 mm. The results of our assessments confirmed that the proposed scheme could provide the location of individual vertebral bodies. Therefore, the proposed scheme may be useful in designing a computer-based application that analyzes vertebral geometry on body CT images.

  12. Dynamic CT myocardial perfusion imaging: detection of ischemia in a porcine model with FFR verification

    NASA Astrophysics Data System (ADS)

    Fahmi, Rachid; Eck, Brendan L.; Vembar, Mani; Bezerra, Hiram G.; Wilson, David L.

    2014-03-01

    Dynamic cardiac CT perfusion (CTP) is a high resolution, non-invasive technique for assessing myocardial blood ow (MBF), which in concert with coronary CT angiography enable CT to provide a unique, comprehensive, fast analysis of both coronary anatomy and functional ow. We assessed perfusion in a porcine model with and without coronary occlusion. To induce occlusion, each animal underwent left anterior descending (LAD) stent implantation and angioplasty balloon insertion. Normal ow condition was obtained with balloon completely de ated. Partial occlusion was induced by balloon in ation against the stent with FFR used to assess the extent of occlusion. Prospective ECG-triggered partial scan images were acquired at end systole (45% R-R) using a multi-detector CT (MDCT) scanner. Images were reconstructed using FBP and a hybrid iterative reconstruction (iDose4, Philips Healthcare). Processing included: beam hardening (BH) correction, registration of image volumes using 3D cubic B-spline normalized mutual-information, and spatio-temporal bilateral ltering to reduce partial scan artifacts and noise variation. Absolute blood ow was calculated with a deconvolutionbased approach using singular value decomposition (SVD). Arterial input function was estimated from the left ventricle (LV) cavity. Regions of interest (ROIs) were identi ed in healthy and ischemic myocardium and compared in normal and occluded conditions. Under-perfusion was detected in the correct LAD territory and ow reduction agreed well with FFR measurements. Flow was reduced, on average, in LAD territories by 54%.

  13. A Structural and Functional Assessment of the Lung via Multidetector-Row Computed Tomography

    PubMed Central

    Hoffman, Eric A.; Simon, Brett A.; McLennan, Geoffrey

    2006-01-01

    With advances in multidetector-row computed tomography (MDCT), it is now possible to image the lung in 10 s or less and accurately extract the lungs, lobes, and airway tree to the fifth- through seventh-generation bronchi and to regionally characterize lung density, texture, ventilation, and perfusion. These methods are now being used to phenotype the lung in health and disease and to gain insights into the etiology of pathologic processes. This article outlines the application of these methodologies with specific emphasis on chronic obstructive pulmonary disease. We demonstrate the use of our methods for assessing regional ventilation and perfusion and demonstrate early data that show, in a sheep model, a regionally intact hypoxic pulmonary vasoconstrictor (HPV) response with an apparent inhibition of HPV regionally in the presence of inflammation. We present the hypothesis that, in subjects with pulmonary emphysema, one major contributing factor leading to parenchymal destruction is the lack of a regional blunting of HPV when the regional hypoxia is related to regional inflammatory events (bronchiolitis or alveolar flooding). If maintaining adequate blood flow to inflamed lung regions is critical to the nondestructive resolution of inflammatory events, the pathologic condition whereby HPV is sustained in regions of inflammation would likely have its greatest effect in the lung apices where blood flow is already reduced in the upright body posture. PMID:16921136

  14. The gamut of primary retroperitoneal masses: multimodality evaluation with pathologic correlation.

    PubMed

    Sangster, Guillermo P; Migliaro, Matias; Heldmann, Maureen G; Bhargava, Peeyush; Hamidian, Alireza; Thomas-Ogunniyi, Jaiyeola

    2016-07-01

    The retroperitoneum is a large space where primary and metastatic tumors grow silently before clinical signs appear. Neoplastic retroperitoneal diseases may be solid or cystic, primary or secondary and range from benign to aggressive in behavior. Retroperitoneal neoplasms are notable for their widely disparate histologies. The solid primary retroperitoneal neoplasms are extremely uncommon and can be classified based on their tissue of origin into three main categories: mesodermal tumors, neurogenic tumors, and extragonadal germ cell tumors. These tumors can grow to a large size before clinical symptoms occur or become palpable. When symptoms do occur, they are nonspecific. The majority of these masses are malignant and imaging plays a pivotal role in the detection, staging, and pre-operative planning. Benign and malignant masses should be distinguished whenever possible to avoid unnecessary surgical procedures. Macroscopic fat, calcification, necrosis, vascularity, and neural foraminal widening are common imaging features helping for tumor differentiation. Meticulous cross-sectional imaging can triage the patient to the most appropriate therapy. Tumor morphology dictates imaging character, and biologic activity is reflected by positron emission tomography (PET). Complete surgical excision with tumor free margins is essential for long-term survival. Biopsy should be performed in consultation with surgical oncology to avoid complicating curative surgery. This pictorial essay illustrates the spectrum of multidetector computed tomography (MDCT) imaging findings in common and uncommon primary retroperitoneal masses, with an emphasis on cross-sectional imaging features for an adequate tumor characterization and staging. PMID:27271217

  15. Shedding New Light on the 18th Dynasty Mummies of the Royal Architect Kha and His Spouse Merit.

    PubMed

    Bianucci, Raffaella; Habicht, Michael E; Buckley, Stephen; Fletcher, Joann; Seiler, Roger; Öhrström, Lena M; Vassilika, Eleni; Böni, Thomas; Rühli, Frank J

    2015-01-01

    The mummies of Kha and his wife Merit were found intact in an undisturbed tomb in western Thebes near the ancient workers' village of Deir el-Medina. Previous MDCT (this abbreviation needs spelling out) investigations showed that the bodies of Kha and Merit did not undergo classical royal 18th Dynasty artificial mummification, which included removal of the internal organs. It was, therefore, concluded that the retention of the viscera in the body, combined with an absence of canopic jars in the burial chamber, meant the couple underwent a short and shoddy funerary procedure, despite their relative wealth at death. Nevertheless, all internal organs - brain, ocular bulbs/ocular nerves, thoracic and abdominal organs - showed a very good state of preservation, which contradicts the previous interpretation above. In order to better understand the type of mummification used to embalm these bodies, both wrapped mummies were reinvestigated using new generation X-ray imaging and chemical microanalyses Here we provide evidence that both individuals underwent a relatively high quality of mummification, fundamentally contradicting previous understanding. Elucidated "recipes", whose components had anti-bacterial and anti-insecticidal properties, were used to treat their bodies. The time and effort undoubtedly employed to embalm both Kha and Merit and the use of imported costly resins, notably Pistacia, do not support the previously held view that the two individuals were poorly mummified. Despite a lack of evisceration, the approach clearly allowed their in situ preservation as well as affording a fairly successful mummification.

  16. Coronary artery calcium score: has anything changed?

    PubMed

    Marano, R; Bonomo, L

    2007-10-01

    Calcium deposition along the coronary artery walls is a surrogate biomarker for atherosclerosis, and its presence in the coronary arteries could reflect the severity of coronary artery disease (CAD) High coronary artery calcium score (CACS) correlates with advanced disease and a higher likelihood of coronary stenoses. Many studies have supported the role of CACS as a screening tool for CAD. Historically, CACS was introduced with electron beam computed tomography (EBCT), but in the last 30 years, many changes have occurred in CT, where the development of multidetector spiral technology has made reliable the noninvasive study of the heart and coronary arteries. Correlation studies with intravascular ultrasound (IVUS) and histology have demonstrated the capability of multidetector CT (MDCT) to provide information useful for characterising atherosclerotic plaque in a noninvasive manner. This has shifted the interest from heavily calcified deposits to plaque with a low-density core and small, superficial calcified nodules, features more frequently present in atherosclerotic plaque prone to rupture and responsible for acute coronary events (culprit lesions). The purpose of this review article is to summarise the recent evolution and revolution in the field of CT, strengthen the importance of a coronary CT study not limited to CACS evaluation and CAD grading but also used to obtain information about plaque composition, and to improve stratification of the patient at risk for acute coronary events. PMID:17952374

  17. An evidence-based guide for coronary calcium scoring in asymptomatic patients without coronary heart disease.

    PubMed

    Shah, Nishant R; Coulter, Stephanie A

    2012-01-01

    As public awareness and clinical use of CAC screening increases, physicians should, at a minimum, know the following information: 1) The presence of CAC indicates underlying CHD but does not predict luminal obstruction. 2) Non-contrast, prospectively ECG-gated cardiac EBCT and MDCT are sensitive, reproducible, rapid, and essentially equivalent imaging techniques commonly used to screen for CAC. 3) Currently, CAC screening is appropriate for all intermediate- risk patients and low-risk patients with a family history of premature CHD, and might be appropriate for all low-risk women. 4) The risks associated with CAC screening are a small but measurable excess risk of cancer and the risk of unnecessary downstream tests and procedures. 5) A CAC score of zero has a very high negative predictive value for CHD events. 6) Increasingly positive (non-zero) CAC scores are directly proportional to increased CHD event risk, and a CAC score >100 or greater than the 75th percentile indicates high risk. 7) Repeat screening to determine CAC progression or regression is not currently recommended. PMID:22740742

  18. Vascular calcification in patients with renal failure: culprit or innocent bystander?

    PubMed

    Dellegrottaglie, Santo; Saran, Rajiv; Rajagopalan, Sanjay

    2005-08-01

    The mortality from cardiovascular events in CKD and dialysis patients is substantially higher than in the general population. VC is ubiquitous and progresses rapidly in this patient population. Although there has been progress in the understanding of the pathogenesis and correlates of VC, much work needs to be done in this area. The role of calcium and, probably, phosphate (obligatory participants) is unquestionable, but the understanding of the paracrine and molecular determinants of VC in renal failure is continuously evolving. VC is probably a dynamic process resulting from the imbalance between molecules that promote and those that inhibit VC. The understanding of latter area has recently evolved with identification of new signaling pathways with molecules such as osteoprotegerin, fetuin-A, and MPG. From a clinical perspective, new modalities such as EBCT and MDCT allow noninvasive detection and quantification of VC. VC may represent a potential useful index for prognostic stratification and treatment planning in patients who have renal failure. At present, however, the data on the prognostic value of VC are available only in populations of patients who have normal renal function. Large-scale, prospective, observational studies should be designed to identify the determinants of VC and to define the prognostic role of calcium scoring in cohorts of patients who have predialysis CKD and with ESRD. PMID:16084285

  19. [Contribution of X-ray computed tomography in the evaluation of kidney performance].

    PubMed

    Lemoine, Sandrine; Rognant, Nicolas; Collet-Benzaquen, Diane; Juillard, Laurent

    2012-07-01

    X-ray computer assisted tomography scanner is an imaging method based on the use of X-ray attenuation in tissue. This attenuation is proportional to the density of the tissue (without or after contrast media injection) in each pixel image of the image. Spiral scanner, the electron beam computed tomography (EBCT) scanner and multidetector computed tomography scanner allow renal anatomical measurements, such as cortical and medullary volume, but also the measurement of renal functional parameters, such as regional renal perfusion, renal blood flow and glomerular filtration rate. These functional parameters are extracted from the modeling of the kinetics of the contrast media concentration in the vascular space and the renal tissue, using two main mathematical models (the gamma variate model and the Patlak model). Renal functional imaging allows measuring quantitative parameters on each kidney separately, in a non-invasive manner, providing significant opportunities in nephrology, both for experimental and clinical studies. However, this method uses contrast media that may alter renal function, thus limiting its use in patients with chronic renal failure. Moreover, the increase irradiation delivered to the patient with multi detector computed tomography (MDCT) should be considered. PMID:22019734

  20. Coronary magnetic resonance angiography.

    PubMed

    Stuber, Matthias; Weiss, Robert G

    2007-08-01

    Coronary magnetic resonance angiography (MRA) is a powerful noninvasive technique with high soft-tissue contrast for the visualization of the coronary anatomy without X-ray exposure. Due to the small dimensions and tortuous nature of the coronary arteries, a high spatial resolution and sufficient volumetric coverage have to be obtained. However, this necessitates scanning times that are typically much longer than one cardiac cycle. By collecting image data during multiple RR intervals, one can successfully acquire coronary MR angiograms. However, constant cardiac contraction and relaxation, as well as respiratory motion, adversely affect image quality. Therefore, sophisticated motion-compensation strategies are needed. Furthermore, a high contrast between the coronary arteries and the surrounding tissue is mandatory. In the present article, challenges and solutions of coronary imaging are discussed, and results obtained in both healthy and diseased states are reviewed. This includes preliminary data obtained with state-of-the-art techniques such as steady-state free precession (SSFP), whole-heart imaging, intravascular contrast agents, coronary vessel wall imaging, and high-field imaging. Simultaneously, the utility of electron beam computed tomography (EBCT) and multidetector computed tomography (MDCT) for the visualization of the coronary arteries is discussed. PMID:17610288

  1. Shedding New Light on the 18th Dynasty Mummies of the Royal Architect Kha and His Spouse Merit

    PubMed Central

    Bianucci, Raffaella; Habicht, Michael E.; Buckley, Stephen; Fletcher, Joann; Seiler, Roger; Öhrström, Lena M.; Vassilika, Eleni; Böni, Thomas; Rühli, Frank J.

    2015-01-01

    The mummies of Kha and his wife Merit were found intact in an undisturbed tomb in western Thebes near the ancient workers’ village of Deir el-Medina. Previous MDCT (this abbreviation needs spelling out) investigations showed that the bodies of Kha and Merit did not undergo classical royal 18th Dynasty artificial mummification, which included removal of the internal organs. It was, therefore, concluded that the retention of the viscera in the body, combined with an absence of canopic jars in the burial chamber, meant the couple underwent a short and shoddy funerary procedure, despite their relative wealth at death. Nevertheless, all internal organs - brain, ocular bulbs/ocular nerves, thoracic and abdominal organs - showed a very good state of preservation, which contradicts the previous interpretation above. In order to better understand the type of mummification used to embalm these bodies, both wrapped mummies were reinvestigated using new generation X-ray imaging and chemical microanalyses Here we provide evidence that both individuals underwent a relatively high quality of mummification, fundamentally contradicting previous understanding. Elucidated “recipes”, whose components had anti-bacterial and anti-insecticidal properties, were used to treat their bodies. The time and effort undoubtedly employed to embalm both Kha and Merit and the use of imported costly resins, notably Pistacia, do not support the previously held view that the two individuals were poorly mummified. Despite a lack of evisceration, the approach clearly allowed their in situ preservation as well as affording a fairly successful mummification. PMID:26200778

  2. Endovascular Embolization of Bronchial Artery Originating from the Upper Portion of Aortic Arch in Patients with Massive Hemoptysis

    SciTech Connect

    Jiang, Sen Sun, Xi-Wen Yu, Dong Jie, Bing

    2013-05-15

    PurposeOur experience with endovascular embolization (EVE) of the bronchial artery (BA) originating from the upper portion of the aortic arch (AA) in six patients is described.MethodsAltogether, 818 patients with hemoptysis underwent multidetector row computed tomography angiography (MDCTA) before EVE or AA angiography during EVE. Aberrant BAs originating from the upper portion of the AA were the source of massive hemoptysis in six patients (0.73 %). MDCT angiograms and/or Digital subtraction angiograms were retrospectively reviewed. Selective catheterization and embolization were performed.ResultsThe ostia of the BAs were located on the superior surface of the AA between the brachiocephalic trunk and left common carotid artery in three patients, the junction of the aorta and medial surface of the left subclavian artery in two, and the posterior wall of the upper portion of the AA in one. The six BAs comprised two common trunks, three single right sides, and one single left side. The targeted vessels were successfully catheterized and embolized by a coaxial microcatheter system using polyvinyl alcohol particles. Other pathologic BAs and nonbronchial systemic arteries also were embolized. Bleeding was immediately controlled in all patients with no recurrence of hemoptysis. No procedure-related complications occurred.ConclusionsApplication of EVE of anomalous origin of BAs in patients with hemoptysis is important, as demonstrated in the six reported patients. MDCTA before EVE or AA angiography during EVE is critical to avoid missing a rare aberrant BA originating from the upper portion of the AA.

  3. Advances in post-mortem CT-angiography

    PubMed Central

    Grimm, J; Dominguez, A; Vanhaebost, J; Mangin, P

    2014-01-01

    Performing a post-mortem multidetector CT (MDCT) scan has already become routine in some institutes of forensic medicine. To better visualize the vascular system, different techniques of post-mortem CT-angiography have been explored, which can essentially be divided into partial- and whole-body angiography techniques. Probably the most frequently applied technique today is the so-called multiphase post-mortem CT-angiography (MPMCTA) a standardized method for investigating the vessels of the head, thorax and abdomen. Different studies exist, describing its use for medicolegal investigations, and its advantages as well as its artefacts and pitfalls. With the aim to investigate the performance of PMCTA and to develop and validate techniques, an international working group was created in 2012 called the “Technical Working Group Post-mortem Angiography Methods” (TWGPAM). Beyond its primary perspective, the goals of this group include creating recommendations for the indication of the investigation and for the interpretation of the images and to distribute knowledge about PMCTA. This article provides an overview about the different approaches that have been developed and tested in recent years and an update about ongoing research in this field. It will explain the technique of MPMCTA in detail and give an outline of its indications, application, advantages and limitations. PMID:24234582

  4. Evolving Frontiers in Severe Polytrauma Management – Refining the Essential Principles

    PubMed Central

    Chak Wah, Kam; Wai Man, Choi; Janet Yuen Ha, Wong; Lai, Vincent; Kit Shing John, Wong

    2013-01-01

    This editorial aims to refine the severe polytrauma management principles. While keeping ABCDE priorities, the termination of futile resuscitation and the early use of tourniquet to stop exsanguinating limb bleeding are crucial. Difficult-airway-management (DAM) is by a structured 5-level approach. The computerised tomography (CT) scanner is the tunnel to death for hemodynamically unstable patients. Focused Abdominal Sonography for Trauma–Ultrasonography (FAST USG) has replaced diagnostic peritoneal lavage (DPL) and is expanding to USG life support. Direct whole-body multidetector-row computed tomography (MDCT) expedites diagnosis & treatment. Non-operative management is a viable option in rapid responders in shock. Damage control resuscitation comprising of permissive hypotension, hemostatic resuscitation & damage control surgery (DCS) help prevent the lethal triad of trauma. Massive transfusion protocol reduces mortality and decreases the blood requirement. DCS attains rapid correction of the deranged physiology. Mortality reduction in major pelvic disruption requires a multi-disciplinary protocol, the novel pre-peritoneal pelvic packing and the angio-embolization. When operation is the definitive treatment for injury, prevention is best therapy. PMID:23785252

  5. Morphological Evaluation of Proximal Anastomosis by PAS-Port® System in Patients with Long-Term Patent Grafts

    PubMed Central

    Fujii, Takeshiro; Hara, Masanori; Sasaki, Yuki; Katayanagi, Tomoyuki; Okuma, Shinnosuke; Watanabe, Yoshinori

    2014-01-01

    Purpose: We examined grafts employing for morphological analysis of early and long-term results on proximal anastomosis with the PAS-Port®. Methods: One hundred and four patients treated by OPCAB with PAS-Port® were performed postoperative MDCT. Morphological evaluation of the proximal anastomotic region was classified into three groups (A; graft was anastomosed almost perpendicularly to the aortic wall, B; graft was same type A, but subsequently curved to form an acute angle with the aortic wall, C; graft take off acute angle with the aortic wall) evaluated on planar and sagittal sections. Results: One hundred twenty-six PAS-Port® were used. Patency rate was 99.0% at discharge, 94.7% at 1 year, and no blockages were detected thereafter in patients examined. The morphology rate was A 50.6%, B 15.3% and C 34.1% on planar sections, and A 58.8%, B 10.6% and C 30.6% on sagittal sections. Conclusion: The morphological evaluation of grafts revealed the degree of freedom in graft design to be relatively high and long-term patency posed no particular problem even if the layout of the proximal anastomotic region involved a relatively acute angle. The PAS-Port® was considered to be a highly reliable device which performed appropriate proximal anastomosis and improved the patency of vein grafting to the aortic wall. PMID:25078547

  6. Cardiovascular events in acromegaly: distinct role of Agatston and Framingham score in the 5-year prediction.

    PubMed

    Ragonese, Marta; Alibrandi, Angela; Di Bella, Gianluca; Salamone, Ignazio; Puglisi, Soraya; Cotta, Oana Ruxandra; Torre, Maria Luisa; Ferrau, Francesco; Ruggeri, Rosaria Maddalena; Trimarchi, Francesco; Cannavo, Salvatore

    2014-09-01

    Prediction of ischemic cardiovascular events (ICE) in acromegalic patients stratified accordingly with Framingham (FS) and Agatston score (AS). 32 patients with active (group A (0)) and 20 with controlled (group B (0)) acromegaly have been enrolled. During the 5-year follow-up, 19 out of 32 patients in group A (0) reached disease control. At entry, FS and AS, by an eight-slice MDCT scanner, were calculated in all patients. ICE were diagnosed by autopsy, if lethal, and by electrocardiography and/or echocardiography, if non-lethal. Overall, 9.6 % of patients died for lethal ICE. AS >400, but not high FS at entry, was associated with increased risk of lethal ICE. Lethal ICE had occurred in two patients of group A (0) and three of group B (0) (p NS), while a non-lethal ICE had occurred in two cases of the former and in other two of the latter group (p NS). Either FS or AS was correlated with the risk for ICE overall (p < 0.02), but only AS correlated with that of lethal ICE (p < 0.0003). Survival analysis demonstrated reduced life expectancy in patients with high FS (p < 0.02). In acromegalics, AS >400 is associated with increased risk of lethal ICE, while high FS is associated with reduced life expectancy, regardless of disease control.

  7. Imaging of laryngeal trauma.

    PubMed

    Becker, Minerva; Leuchter, Igor; Platon, Alexandra; Becker, Christoph D; Dulguerov, Pavel; Varoquaux, Arthur

    2014-01-01

    External laryngeal trauma is a rare but potentially life-threatening situation in the acutely injured patient. Trauma mechanism and magnitude, maximum focus of the applied force, and patient related factors, such as age and ossification of the laryngeal cartilages influence the spectrum of observed injuries. Their correct diagnosis and prompt management are paramount in order to avoid patient death or long-term impairment of breathing, swallowing and speaking. The current review provides a comprehensive approach to the radiologic interpretation of imaging studies performed in patients with suspected laryngeal injury. It describes the key anatomic structures that are relevant in laryngeal trauma and discusses the clinical role of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the acute emergency situation. The added value of two-dimensional multiplanar reconstructions (2D MPR), three-dimensional volume rendering (3D VR) and virtual endoscopy (VE) for the non-invasive evaluation of laryngeal injuries and for treatment planning is discussed. The clinical presentation, biomechanics of injury, diagnostic pitfalls and pearls, common and uncommon findings are reviewed with emphasis of fracture patterns, involvement of laryngeal joints, intra- and extralaryngeal soft tissue injuries, and complications seen in the acute emergency situation. The radiologic appearance of common and less common long-term sequelae, as well as treatment options are equally addressed.

  8. Time-frequency scale decomposition of tectonic tremor signals for space-time reconstruction of tectonic tremor sources

    NASA Astrophysics Data System (ADS)

    Poiata, N.; Satriano, C.; Vilotte, J. P.; Bernard, P.; Obara, K.

    2015-12-01

    Seismic radiation associated with transient deformations along the faults and subduction interfaces encompasses a variety of events, i.e., tectonic tremors, low-frequency earthquakes (LFE), very low-frequency earthquakes (VLFs), and slow-slip events (SSE), with a wide range of seismic moment and characteristic durations. Characterizing in space and time the complex sources of these slow earthquakes, and their relationship with background seismicity and large earthquakes generation, is of great importance for understanding the physics and mechanics of the processes of active deformations along the plate interfaces. We present here first developments towards a methodology for: (1) extracting the different frequency and scale components of observed tectonic tremor signal, using advanced time-frequency and time-scale signal representation such as Gabor transform scheme based on, e.g. Wilson bases or Modified Discrete Cosine Transform (MDCT) bases; (2) reconstructing their corresponding potential sources in space and time, using the array method of Poiata et al. (2015). The methodology is assessed using a dataset of tectonic tremor episodes from Shikoku, Japan, recorded by the Hi-net seismic network operated by NIED. We illustrate its performance and potential in providing activity maps - associated to different scale-components of tectonic tremors - that can be analyzed statistically to improve our understanding of tremor sources and scaling, as well as their relation with the background seismicity.

  9. Embolization of traumatic and non-traumatic peripheral vascular lesions with Onyx

    PubMed Central

    Regine, Renato; De Siero, Michele; Rescigno, Antonio; Sica, Vincenzo; Cantarela, Raffaele; Villari, Vincenzo

    2015-01-01

    Purpose The aim of our study is to verify the feasibility and the efficacy of Onyx as embolization agent in the treatment of traumatic and non-traumatic peripheral vascular lesions. Materials and Methods In the period between September 2006 and March 2012, we treated with Onyx 26 patients (14 males/12 females; age range, 18–85 years old; mean age, 65 years old), 11 of which with traumatic peripheral vascular lesions and 15 with non-traumatic vascular lesions (9 neoplastic hemorrhagic lesions, 3 arteriovenous malformations (AVMs) and 3 aneurysms). Follow-up controls were performed with clinical examination and by multidetector computed tomography (MDCT) imaging 1, 6, and 12 months after the procedure. Results All peripheral vascular lesions were embolized with Onyx; 3 patients with aneurysms were treated with Onyx associated with endovascular coils. Four elective and 22 emergency embolization procedures were performed. In all patients, we obtained cessation of bleeding and the complete and permanent embolization of all vascular lesions. Conclusions Onyx is an effective and safe embolization agent for peripheral vascular lesions. PMID:25838923

  10. [Motion analysis of target in stereotactic radiotherapy of lung tumors using 320-row multidetector CT].

    PubMed

    Imae, Toshikazu; Haga, Akihiro; Nakagawa, Keiichi; Ino, Kenji; Tanaka, Kenichirou; Okano, Yukari; Sasaki, Katsutake; Saegusa, Shigeki; Shiraki, Takashi; Oritate, Takashi; Yano, Keiichi; Shinohara, Hiroyuki

    2011-01-01

    Multi-detector computed tomography (MDCT) has rapidly evolved and is increasingly used for treatment simulation of thoracic and abdominal radiotherapy. A 320-detector row CT scanner has recently become available that allows axial volumetric scanning of a 16-cm-long range in a patient without table movement. Current radiotherapy techniques require a generous margin around the presumed gross tumor volume (GTV) to account for uncertainties such as tumor motion and set up error. Motion analysis is useful to evaluate the internal margin of a moving target due to respiration and to improve therapeutic precision. The purpose of this study is to propose a method using phase-only correlation to automatically detect the target and to assess the motion of the target in numerical phantoms and patients. Free-breathing scans using 320-detector row CT were acquired for 4 patients with lung tumor(s). The proposed method was feasible for motion analysis of all numerical phantoms and patients. The results reproduced the facts that the motion of tumors in the patients varied in orbits during the respiratory cycle and exhibited hysteresis. The maximum distance between peak exhalation and inhalation increased as the tumors approached the diaphragm. The proposed method detected the three-dimensional position of the targets automatically and analyzed the trajectories. The tumor motion due to respiration differed by region and was greatest for the lower lobe. PMID:21471676

  11. Imaging of laryngeal trauma.

    PubMed

    Becker, Minerva; Leuchter, Igor; Platon, Alexandra; Becker, Christoph D; Dulguerov, Pavel; Varoquaux, Arthur

    2014-01-01

    External laryngeal trauma is a rare but potentially life-threatening situation in the acutely injured patient. Trauma mechanism and magnitude, maximum focus of the applied force, and patient related factors, such as age and ossification of the laryngeal cartilages influence the spectrum of observed injuries. Their correct diagnosis and prompt management are paramount in order to avoid patient death or long-term impairment of breathing, swallowing and speaking. The current review provides a comprehensive approach to the radiologic interpretation of imaging studies performed in patients with suspected laryngeal injury. It describes the key anatomic structures that are relevant in laryngeal trauma and discusses the clinical role of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the acute emergency situation. The added value of two-dimensional multiplanar reconstructions (2D MPR), three-dimensional volume rendering (3D VR) and virtual endoscopy (VE) for the non-invasive evaluation of laryngeal injuries and for treatment planning is discussed. The clinical presentation, biomechanics of injury, diagnostic pitfalls and pearls, common and uncommon findings are reviewed with emphasis of fracture patterns, involvement of laryngeal joints, intra- and extralaryngeal soft tissue injuries, and complications seen in the acute emergency situation. The radiologic appearance of common and less common long-term sequelae, as well as treatment options are equally addressed. PMID:24238937

  12. Computed tomographic colonography (CTC): Possibilities and limitations of clinical application in colorectal polyps and cancer.

    PubMed

    Heuschmid, Martin; Luz, Oliver; Schaefer, Juergen F; Kopp, Andreas F; Claussen, Claus D; Seemann, Marcus D

    2004-04-01

    Colorectal cancer is the second leading cause of cancer-related deaths i