[Values of computed tomography angiogram in non-cardiac surgery planning and cardiac risk assessment of coronary atherosclerosis during perioperative period].

PubMed

Chang, Rui-ping; Ju, Hai-yue; Zhang, Xing-hua; Wu, Jian; Zhang, Fan; Mi, Wei-dong; Cao, Xiu-tang; Gao, Chang-qing; Yang, Li

2013-02-19

To explore the values of detecting coronary atherosclerosis by computed tomography angiogram (CTA) on non-cardiac surgery planning and cardiac risk assessment of coronary atherosclerosis during perioperative period. A total of 89 patients with suspected coronary heart disease (CHD) scheduled for non-cardiac surgery underwent coronary CTA to evaluate luminal stenosis and calculate calcification score. There were 56 males and 33 females with a mean age of 65.1 years. Operative sites included chests (n = 29), abdomens and pelvis (n = 26), large vessels (n = 3), bones and joints (n = 19) and other regions (n = 12). Reasons of abandoned or postponed surgery were documented to analyze the influence of CTA results on surgery planning. Cardiac events were recorded to assess the correlation with coronary atherosclerosis. Among them, 75 patients (84.27%) were diagnosed as atherosclerosis while 10 patients (11.24%) were negative; 2 patients had coronary artery bypass and another 2 had stent implantation. According to the results of CTA, 12 operations (13.48%) were canceled and 8 (8.98%) postponed after interventions. Severe stenosis of coronary lumen had significant effects on surgery planning (P = 0.003) while calcification score did not. In patients undergoing surgery as scheduled or after intervention, 1 had atrial fibrillation at post-operation. For the patients with suspected CHD scheduled for non-cardiac surgery, severity of coronary stenosis may greatly influence surgery planning. Preoperative coronary CTA may decrease the incidence of cardiac events during perioperative period.

A Quantitative Approach to Distinguish Pneumonia From Atelectasis Using Computed Tomography Attenuation.

PubMed

Edwards, Rachael M; Godwin, J David; Hippe, Dan S; Kicska, Gregory

2016-01-01

It is known that atelectasis demonstrates greater contrast enhancement than pneumonia on computed tomography (CT). However, the effectiveness of using a Hounsfield unit (HU) threshold to distinguish pneumonia from atelectasis has never been shown. The objective of the study is to demonstrate that an HU threshold can be quantitatively used to effectively distinguish pneumonia from atelectasis. Retrospectively identified CT pulmonary angiogram examinations that did not show pulmonary embolism but contained nonaerated lungs were classified as atelectasis or pneumonia based on established clinical criteria. The HU attenuation was measured in these nonaerated lungs. Receiver operating characteristic (ROC) analysis was performed to determine the area under the ROC curve, sensitivity, and specificity of using the attenuation to distinguish pneumonia from atelectasis. Sixty-eight nonaerated lungs were measured in 55 patients. The mean (SD) enhancement was 62 (18) HU in pneumonia and 119 (24) HU in atelectasis (P < 0.001). A threshold of 92 HU diagnosed pneumonia with 97% sensitivity (confidence interval [CI], 80%-99%) and 85% specificity (CI, 70-93). Accuracy, measured as area under the ROC curve, was 0.97 (CI, 0.89-0.99). We have established that a threshold HU value can be used to confidently distinguish pneumonia from atelectasis with our standard CT pulmonary angiogram imaging protocol and patient population. This suggests that a similar threshold HU value may be determined for other scanning protocols, and application of this threshold may facilitate a more confident diagnosis of pneumonia and thus speed treatment.

SENSITIVITY AND SPECIFICITY OF DETECTING POLYPOIDAL CHOROIDAL VASCULOPATHY WITH EN FACE OPTICAL COHERENCE TOMOGRAPHY AND OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

PubMed

de Carlo, Talisa E; Kokame, Gregg T; Kaneko, Kyle N; Lian, Rebecca; Lai, James C; Wee, Raymond

2018-03-20

Determine sensitivity and specificity of polypoidal choroidal vasculopathy (PCV) diagnosis with structural en face optical coherence tomography (OCT) and OCT angiography (OCTA). Retrospective review of the medical records of eyes diagnosed with PCV by indocyanine green angiography with review of diagnostic testing with structural en face OCT and OCTA by a trained reader. Structural en face OCT, cross-sectional OCT angiograms alone, and OCTA in its entirety were reviewed blinded to the findings of indocyanine green angiography and each other to determine if they could demonstrate the PCV complex. Sensitivity and specificity of PCV diagnosis was determined for each imaging technique using indocyanine green angiography as the ground truth. Sensitivity and specificity of structural en face OCT were 30.0% and 85.7%, of OCT angiograms alone were 26.8% and 96.8%, and of the entire OCTA were 43.9% and 87.1%, respectively. Sensitivity and specificity were improved for OCT angiograms and OCTA when looking at images taken within 1 month of PCV diagnosis. Sensitivity of detecting PCV was low using structural en face OCT and OCTA but specificity was high. Indocyanine green angiography remains the gold standard for PCV detection.

Superior mesenteric artery syndrome in a young military basic trainee.

PubMed

Schauer, Steven G; Thompson, Andrew J; Bebarta, Vikhyat S

2013-03-01

We report the case of a 19-year-old military trainee that presented to the emergency department with a 3-week history of diffuse abdominal pain, 1 to 2 hours postprandially. The timing, onset, quality, and location of her pain was concerning for intestinal angina. Her serum chemistry, hematology, and liver function tests were normal. The radiologist's interpretation of the computed tomography angiogram of the abdomen was an abnormally narrow takeoff angle of the superior mesenteric artery (SMA) from the aorta near the third portion of the duodenum. She was diagnosed with SMA syndrome and received additional evaluation and treatment by her gastroenterologist and surgeon. SMA syndrome is rare and can cause bowel obstruction, perforation, gastric wall pneumatosis, and portal venous gas formation. Computed tomography angiography can be used to promptly diagnose this syndrome in the emergency department. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

Computed tomography angiography-fluoroscopy image fusion allows visceral vessel cannulation without angiography during fenestrated endovascular aneurysm repair.

PubMed

Schwein, Adeline; Chinnadurai, Ponraj; Behler, Greg; Lumsden, Alan B; Bismuth, Jean; Bechara, Carlos F

2018-07-01

Fenestrated endovascular aneurysm repair (FEVAR) is an evolving technique to treat juxtarenal abdominal aortic aneurysms (AAAs). Catheterization of visceral and renal vessels after the deployment of the fenestrated main body device is often challenging, usually requiring additional fluoroscopy and multiple digital subtraction angiograms. The aim of this study was to assess the clinical utility and accuracy of a computed tomography angiography (CTA)-fluoroscopy image fusion technique in guiding visceral vessel cannulation during FEVAR. Between August 2014 and September 2016, all consecutive patients who underwent FEVAR at our institution using image fusion guidance were included. Preoperative CTA images were fused with intraoperative fluoroscopy after coregistering with non-contrast-enhanced cone beam computed tomography (syngo 3D3D image fusion; Siemens Healthcare, Forchheim, Germany). The ostia of the visceral vessels were electronically marked on CTA images (syngo iGuide Toolbox) and overlaid on live fluoroscopy to guide vessel cannulation after fenestrated device deployment. Clinical utility of image fusion was evaluated by assessing the number of dedicated angiograms required for each visceral or renal vessel cannulation and the use of optimized C-arm angulation. Accuracy of image fusion was evaluated from video recordings by three raters using a binary qualitative assessment scale. A total of 26 patients (17 men; mean age, 73.8 years) underwent FEVAR during the study period for juxtarenal AAA (17), pararenal AAA (6), and thoracoabdominal aortic aneurysm (3). Video recordings of fluoroscopy from 19 cases were available for review and assessment. A total of 46 vessels were cannulated; 38 of 46 (83%) of these vessels were cannulated without angiography but based only on image fusion guidance: 9 of 11 superior mesenteric artery cannulations and 29 of 35 renal artery cannulations. Binary qualitative assessment showed that 90% (36/40) of the virtual ostia overlaid on live fluoroscopy were accurate. Optimized C-arm angulations were achieved in 35% of vessel cannulations (0/9 for superior mesenteric artery cannulation, 12/25 for renal arteries). Preoperative CTA-fluoroscopy image fusion guidance during FEVAR is a valuable and accurate tool that allows visceral and renal vessel cannulation without the need of dedicated angiograms, thus avoiding additional injection of contrast material and radiation exposure. Further refinements, such as accounting for device-induced aortic deformation and automating the image fusion workflow, will bolster this technology toward optimal routine clinical use. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Dynamic three-dimensional model of the coronary circulation

NASA Astrophysics Data System (ADS)

Lehmann, Glen; Gobbi, David G.; Dick, Alexander J.; Starreveld, Yves P.; Quantz, M.; Holdsworth, David W.; Drangova, Maria

2001-05-01

A realistic numerical three-dimensional (3D) model of the dynamics of human coronary arteries has been developed. High- resolution 3D images of the coronary arteries of an excised human heart were obtained using a C-arm based computed tomography (CT) system. Cine bi-plane coronary angiograms were then acquired from a patient with similar coronary anatomy. These angiograms were used to determine the vessel motion, which was applied to the static 3D coronary tree. Corresponding arterial bifurcations were identified in the 3D CT image and in the 2D angiograms. The 3D positions of the angiographic landmarks, which were known throughout the cardiac cycle, were used to warp the 3D image via a non-linear thin-plate spline algorithm. The result was a set or 30 dynamic volumetric images sampling a complete cardiac cycle. To the best of our knowledge, the model presented here is the first dynamic 3D model that provides a true representation of both the geometry and motion of a human coronary artery tree. In the future, similar models can be generated to represent different coronary anatomy and motion. Such models are expected to become an invaluable tool during the development of dynamic imaging techniques such as MRI, multi-slice CT and 3D angiography.

Computer measurement of arterial disease

NASA Technical Reports Server (NTRS)

Armstrong, J.; Selzer, R. H.; Barndt, R.; Blankenhorn, D. H.; Brooks, S.

1980-01-01

Image processing technique quantifies human atherosclerosis by computer analysis of arterial angiograms. X-ray film images are scanned and digitized, arterial shadow is tracked, and several quantitative measures of lumen irregularity are computed. In other tests, excellent agreement was found between computer evaluation of femoral angiograms on living subjects and evaluation by teams of trained angiographers.

Computer assessment of atherosclerosis from angiographic images

NASA Technical Reports Server (NTRS)

Selzer, R. H.; Blankenhorn, D. H.; Brooks, S. H.; Crawford, D. W.; Cashin, W. L.

1982-01-01

A computer method for detection and quantification of atherosclerosis from angiograms has been developed and used to measure lesion change in human clinical trials. The technique involves tracking the vessel edges and measuring individual lesions as well as the overall irregularity of the arterial image. Application of the technique to conventional arterial-injection femoral and coronary angiograms is outlined and an experimental study to extend the technique to analysis of intravenous angiograms of the carotid and cornary arteries is described.

Microscope-Integrated Optical Coherence Tomography Angiography in the Operating Room in Young Children With Retinal Vascular Disease.

PubMed

Chen, Xi; Viehland, Christian; Carrasco-Zevallos, Oscar M; Keller, Brenton; Vajzovic, Lejla; Izatt, Joseph A; Toth, Cynthia A

2017-05-01

Intraoperative optical coherence tomography (OCT) has gained traction as an important adjunct for clinical decision making during vitreoretinal surgery, and OCT angiography (OCTA) has provided novel insights in clinical evaluation of retinal diseases. To date, these two technologies have not been applied in combination to evaluate retinal vascular disease in the operating suite. To conduct microscope-integrated, swept-source OCTA (MIOCTA) in children with retinal vascular disease. In this case report analysis, OCT imaging in pediatric patients, MIOCTA images were obtained during examination under anesthesia from a young boy with a history of idiopathic vitreous hemorrhage and a female infant with familial exudative vitreoretinopathy. Side-by-side comparison of research MIOCT angiograms and clinically indicated fluorescein angiograms. In 2 young children with retinal vascular disease, the MIOCTA images showed more detailed vascular patterns than were visible on the fluorescein angiograms although within a more posterior field of view. The MIOCTA system allowed visualization of small pathological retinal vessels in the retinal periphery that were obscured in the fluorescein angiograms by fluorescein staining from underlying, preexisting laser scars. This is the first report to date of the use of MIOCTA in the operating room for young children with retinal vascular disease. Further optimization of this system may allow noninvasive detailed evaluation of retinal vasculature during surgical procedures and in patients who could not cooperate with in-office examinations.

Endovascular Approach for Management of Bullet Embolization to the Heart.

PubMed

Mojtahedi, Alireza; Contractor, Sohail; Kisza, Piotr S

2018-05-01

Bullet embolization to the right heart through the vasculature is seen infrequently in cases presenting with penetrating trauma. Patients with unstable hemodynamic status are managed operatively. For a patient with stable hemodynamic parameters, diagnostic evaluation such as computed tomography angiogram, echocardiogram, or angiography could be performed to select the best treatment option. Endovascular treatment is employed infrequently in these cases but can be a viable option for select patients. We present a case of a bullet embolus to the right ventricle treated successfully with endovascular approach and discuss the technical aspects of this approach.

Spontaneous Recanalization After Carotid Artery Dissection: The Case for an Ultrasound-Only Monitoring Strategy

PubMed Central

Lumsden, Sarah; Rosta, Gabor; Bismuth, Jean; Lumsden, Alan B.; Garami, Zsolt

2017-01-01

Dissection of the internal carotid artery (ICA) accounts for 5% to 25% of ischemic strokes in young adults. We report a case of spontaneous recanalization of a traumatic ICA dissection in which carotid duplex (CDU) and transcranial color-coded duplex ultrasound (TCCD) were used. A 47-year-old male presented with intermittent episodes of headache, blurry vision, anisocoria, and loss of taste sensation following a whiplash injury while body surfing. Magnetic resonance angiogram (MRA) of the neck revealed absent flow in the cavernous ICA and a clot at the skull base. Carotid duplex, used to further evaluate flow, demonstrated reverberating color Doppler and spectrum signal. A TCCD showed ICA occlusion and smaller-caliber intracranial ICA. The patient reported for follow-up after 1 month on anticoagulation therapy. Upon his return, CDU and TCCD were normal and the ICA showed normal color and spectrum signals. Computed tomography angiogram confirmed ultrasound findings of a dramatic improvement of ICA patency. Additionally, the patient reported that his headaches had resolved. Extracranial CDU and TCCD are useful for monitoring patient progress in cases of spontaneous recanalization following carotid artery dissection. These inexpensive and noninvasive imaging modalities proved to be critical in the initial and follow-up evaluations of the extracranial and intracranial vascular system, providing a strong alternative to expensive magnetic resonance imaging and invasive angiograms and offering more hemodynamic information than “static” MRA. PMID:29744017

Liquid metal angiography for mega contrast X-ray visualization of vascular network in reconstructing in-vitro organ anatomy.

PubMed

Wang, Qian; Yu, Yang; Pan, Keqin; Liu, Jing

2014-07-01

Visualization on the anatomical vessel networks plays a vital role in the physiological or pathological investigations. However, so far it still remains a big challenge to identify the fine structures of the smallest capillary vessel networks via conventional imaging ways. Here, the room temperature liquid metal angiography was proposed for the first time to generate mega contrast X-ray images for multiscale vasculature mapping. Particularly, gallium was adopted as the room temperature liquid metal contrast agent and infused into the vessels of in vitro pig hearts and kidneys. We scanned the samples under X-ray and compared the angiograms with those obtained via conventional contrast agent--the iohexol. As quantitatively demonstrated by the grayscale histograms and numerical indexes, the contrast of the vessels to the surrounding tissues in the liquid metal angiograms is orders higher than that of the iohexol enhanced images. And the angiogram has reached detailed enough width of 0.1 mm for the tiny vessels, which indicated that the capillaries can be clearly distinguished under the liquid metal enhanced images. Further, with tomography from the micro-CT, we also managed to reconstruct the 3-D structures of the kidney vessels. Tremendous clarity and efficiency of the method over existing approaches have been experimentally clarified. It was disclosed that the usually invisible capillary networks now become distinctively clear in the gallium angiograms. This basic mechanism has generalized purpose and can be extended to a wide spectrum of 3-D computational tomographic areas. It opens a new soft tool for quickly reconstructing high-resolution spatial channel networks for scientific researches as well as engineering practices where complicated and time-consuming resections are no longer a necessity.

Outcome Following a Negative CT Angiogram for Gastrointestinal Hemorrhage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Victoria, E-mail: drvictoriac@gmail.com; Tse, Donald, E-mail: donald.tse@gmail.com; Dixon, Shaheen, E-mail: shaheen7noorani@gmail.com

2015-04-15

ObjectiveThis study was designed to evaluate the role of a negative computed tomography angiogram (CTA) in patients who present with gastrointestinal (GI) hemorrhage.MethodsA review of all patients who had CTAs for GI hemorrhage over an 8-year period from January 2005 to December 2012 was performed. Data for patient demographics, location of hemorrhage, hemodynamic stability, and details of angiograms and/or the embolization procedure were obtained from the CRIS/PACS database, interventional radiology database, secure electronic medical records, and patient’s clinical notes.ResultsA total of 180 patients had 202 CTAs during the 8-year period: 87 CTAs were performed for upper GI hemorrhage (18 positivemore » for active bleeding, 69 negative) and 115 for lower GI hemorrhage (37 positive for active bleeding, 78 negative); 58.7 % (37/63) of patients with upper GI bleed and 77.4 % (48/62) of patients with lower GI bleed who had an initial negative CTA did not rebleed without the need for radiological or surgical intervention. This difference was statistically significant (p = 0.04). The relative risk of rebleeding, following a negative CTA, in lower GI bleeding versus upper GI bleeding patients is 0.55 (95 % confidence interval 0.32–0.95).ConclusionsPatients with upper GI bleed who had negative CTAs usually require further intervention to stop the bleeding. In contrast, most patients presenting with lower GI hemorrhage who had a negative first CTA were less likely to rebleed.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Jin Woo; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Chung, Jin Wook

Purpose: This study was designed to evaluate the radiologic findings and imaging response of chemoembolization via branches of the splenic artery in patients with hepatocellular carcinoma (HCC). Methods: From January 2001 to July 2010, we observed tumor staining supplied by branches of the splenic artery in 34 (0.6%) of 5,413 patients with HCC. Computed tomography (CT) scans and digital subtraction angiograms of these patients were retrospectively reviewed in consensus by two investigators. Results: A total of 39 tumor feeding-vessels in 34 patients were identified: omental branches from the left gastroepiploic artery (n = 5), branches from the short gastric arterymore » (n = 9), and omental branches directly from the splenic artery (n = 25). Branches of the splenic artery that supplied tumors were revealed on the celiac angiogram in 29 (85%) of 34 patients and were detected on pre-procedure CT images in 27 (79%) of 34 patients. Selective chemoembolization was achieved in 38 of 39 tumor-feeding vessels. Complete or partial response of the tumor fed by branches of the splenic artery, as depicted on follow-up CT scans, was achieved in 21 (62%) patients. No patient developed severe complications directly related to chemoembolization via branches of the splenic artery. Conclusions: Omental branches directly from the splenic artery are common tumor-feeding vessels of the splenic artery in cases of advanced HCC with multiple previous chemoembolizations. Tumor-feeding vessels of the splenic artery are usually visualized on the celiac angiogram or CT scan, and chemoembolization through them can be safely performed in most patients.« less

Coronary Artery Dissection: Not Just a Heart Attack

MedlinePlus

... using an angiogram , but an intravascular ultrasound or optical coherence tomography screening, which allows doctors to see ... Changes Recovery FAQs • Heart Attack Tools & Resources • Support Network Watch, Learn and Live Our Interactive Cardiovascular Library ...

Deep Circumflex Iliac Artery-Related Hemoperitoneum Formation After Surgical Drain Placement: Successful Transcatheter Embolization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Sang Woo; Chang, Seong-Hwan, E-mail: csh@kuh.ac.kr; Yun, Ik Jin

A 53-year-old woman with liver cirrhosis and hepatocellular carcinoma underwent living donor liver transplantation. After transplantation, her hemoglobin and hematocrit levels decreased to 6.3 g/dl and 18.5%, respectively, during the course of 3 days. A contrast-enhanced abdominal computed axial tomography (CAT) scan showed a hemoperitoneum in the right perihepatic space with no evidence of abdominal wall hematoma or pseudoaneurysm formation. An angiogram of the deep circumflex iliac artery (DCIA) showed extravasation of contrast media along the surgical drain, which had been inserted during the transplantation procedure. Transcatheter embolization of the branches of the DCIA was successfully performed using N-butyl cyanoacrylate.

Psychiatric Characteristics of the Cardiac Outpatients with Chest Pain.

PubMed

Lee, Jea-Geun; Choi, Joon Hyouk; Kim, Song-Yi; Kim, Ki-Seok; Joo, Seung-Jae

2016-03-01

A cardiologist's evaluation of psychiatric symptoms in patients with chest pain is rare. This study aimed to determine the psychiatric characteristics of patients with and without coronary artery disease (CAD) and explore their relationship with the intensity of chest pain. Out of 139 consecutive patients referred to the cardiology outpatient department, 31 with atypical chest pain (heartburn, acid regurgitation, dyspnea, and palpitation) were excluded and 108 were enrolled for the present study. The enrolled patients underwent complete numerical rating scale of chest pain and the symptom checklist for minor psychiatric disorders at the time of first outpatient visit. The non-CAD group consisted of patients with a normal stress test, coronary computed tomography angiogram, or coronary angiogram, and the CAD group included those with an abnormal coronary angiogram. Nineteen patients (17.6%) were diagnosed with CAD. No differences in the psychiatric characteristics were observed between the groups. "Feeling tense", "self-reproach", and "trouble falling asleep" were more frequently observed in the non-CAD (p=0.007; p=0.046; p=0.044) group. In a multiple linear regression analysis with a stepwise selection, somatization without chest pain in the non-CAD group and hypochondriasis in the CAD group were linearly associated with the intensity of chest pain (β=0.108, R(2)=0.092, p=0.004; β= -0.525, R(2)=0.290, p=0.010). No differences in psychiatric characteristics were observed between the groups. The intensity of chest pain was linearly associated with somatization without chest pain in the non-CAD group and inversely linearly associated with hypochondriasis in the CAD group.

Management of Zone III Missile Injuries Involving the Carotid Artery and Cranial Nerves

PubMed Central

Levine, Zachary T.; Wright, Donald C.; O'Malley, Sean; Olan, Wayne J.; Sekhar, Laligam N.

2000-01-01

Carotid and cranial nerve injuries from zone III (high cervical/cranial base) missile injuries are rare and difficult to treat. We have treated five patients with such injuries. We present our management scheme, and compare it to the management of the same injuries in other reports. Five consecutive zone III missile injuries presented to our institution. Trauma assessment by the trauma team, followed by detailed neurological assessment and radiographs (angiogram and computed tomography) were obtained on admission. All patients presented with dysphagia and carotid artery injury with good collateral flow, documented by angiogram. Two patients had facial nerve injury, one had trigeminal nerve injury, one patient presented with tongue weakness, and one patient suffered conductive hearing loss. No patient had evidence of stroke clinically or radiographically. Carotid artery injury was managed with bypass (3 of 5) or ligation (2 of 5). Cranial nerve injuries were documented and treated aggressively with surgery if needed. All patients were discharged to home. Patients presenting with zone III missile injuries should receive an expeditious neurological exam and four-vessel angiogram after initial trauma survey and resuscitation. Bypass of the injured portion of carotid artery is a valid treatment in the hemodynamically stable patient. The unstable patient should undergo ligation to stop hemorrhage and protect against immediate risk for stroke, with the option to bypass later. Cranial nerve injuries should be pursued and aggressively treated to minimize morbidity and prevent mortality. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8 PMID:17171097

CAD-RADS - a new clinical decision support tool for coronary computed tomography angiography.

PubMed

Foldyna, Borek; Szilveszter, Bálint; Scholtz, Jan-Erik; Banerji, Dahlia; Maurovich-Horvat, Pál; Hoffmann, Udo

2018-04-01

Coronary computed tomography angiography (CTA) has been established as an accurate method to non-invasively assess coronary artery disease (CAD). The proposed 'Coronary Artery Disease Reporting and Data System' (CAD-RADS) may enable standardised reporting of the broad spectrum of coronary CTA findings related to the presence, extent and composition of coronary atherosclerosis. The CAD-RADS classification is a comprehensive tool for summarising findings on a per-patient-basis dependent on the highest-grade coronary artery lesion, ranging from CAD-RADS 0 (absence of CAD) to CAD-RADS 5 (total occlusion of a coronary artery). In addition, it provides suggestions for clinical management for each classification, including further testing and therapeutic options. Despite some limitations, CAD-RADS may facilitate improved communication between imagers and patient caregivers. As such, CAD-RADS may enable a more efficient use of coronary CTA leading to more accurate utilisation of invasive coronary angiograms. Furthermore, widespread use of CAD-RADS may facilitate registry-based research of diagnostic and prognostic aspects of CTA. • CAD-RADS is a tool for standardising coronary CTA reports. • CAD-RADS includes clinical treatment recommendations based on CTA findings. • CAD-RADS has the potential to reduce variability of CTA reports.

Unusual presentation of pheochromocytoma with ischemic sigmoid colitis and stenosis.

PubMed

Tan, Florence; Thai, Ah Chuan; Cheah, Wei Keat; Mukherjee, J J

2009-10-01

A 45-year-old woman with poorly controlled hypertension and diabetes mellitus presented with left iliac fossa pain, constipation alternating with diarrhea, and weight loss. She had been diagnosed with idiopathic cardiomyopathy five years previously. Echocardiogram had shown a left ventricular ejection fraction (LVEF) of 35%; coronary angiogram was normal. Colonoscopy revealed sigmoid colitis with stenosis. Abdominal computed tomography revealed a 5 cm right adrenal tumor. Twenty-four hour urinary free catecholamines and fractionated metanephrine excretion values were elevated, confirming pheochromocytoma. Her colitis resolved after one month of adrenergic blockade. Repeat echocardiogram showed improvement of LVEF to 65%. After laparoscopic right adrenalectomy, the patient's hypertension resolved, and diabetic control improved. Timely management avoided further morbidity and potential mortality in our patient.

Interpretation of Coronary Angiograms Recorded Using Google Glass: A Comparative Analysis.

PubMed

Duong, Thao; Wosik, Jedrek; Christakopoulos, Georgios E; Martínez Parachini, José Roberto; Karatasakis, Aris; Tarar, Muhammad Nauman Javed; Resendes, Erica; Rangan, Bavana V; Roesle, Michele; Grodin, Jerrold; Abdullah, Shuaib M; Banerjee, Subhash; Brilakis, Emmanouil S

2015-10-01

Google Glass (Google, Inc) is a voice-activated, hands-free, optical head-mounted display device capable of taking pictures, recording videos, and transmitting data via wi-fi. In the present study, we examined the accuracy of coronary angiogram interpretation, recorded using Google Glass. Google Glass was used to record 15 angiograms with 17 major findings and the participants were asked to interpret those recordings on: (1) an iPad (Apple, Inc); or (2) a desktop computer. Interpretation was compared with the original angiograms viewed on a desktop. Ten physicians (2 interventional cardiologists and 8 cardiology fellows) participated. One point was assigned for each correct finding, for a maximum of 17 points. The mean angiogram interpretation score for Google Glass angiogram recordings viewed on an iPad or a desktop vs the original angiograms viewed on a desktop was 14.9 ± 1.1, 15.2 ± 1.8, and 15.9 ± 1.1, respectively (P=.06 between the iPad and the original angiograms, P=.51 between the iPad and recordings viewed on a desktop, and P=.43 between the recordings viewed on a desktop and the original angiograms). In a post-study survey, one of the 10 physicians (10%) was "neutral" with the quality of the recordings using Google Glass, 6 physicians (60%) were "somewhat satisfied," and 3 physicians (30%) were "very satisfied." This small pilot study suggests that the quality of coronary angiogram video recordings obtained using Google Glass may be adequate for recognition of major findings, supporting its expanding use in telemedicine.

Enhanced visualization of peripheral retinal vasculature with wavefront sensorless adaptive optics OCT angiography in diabetic patients

PubMed Central

Polans, James; Cunefare, David; Cole, Eli; Keller, Brenton; Mettu, Priyatham S.; Cousins, Scott W.; Allingham, Michael J.; Izatt, Joseph A.; Farsiu, Sina

2017-01-01

Optical coherence tomography angiography (OCTA) is a promising technique for non-invasive visualization of vessel networks in the human eye. We debut a system capable of acquiring wide field-of-view (>70°) OCT angiograms without mosaicking. Additionally, we report on enhancing the visualization of peripheral microvasculature using wavefront sensorless adaptive optics (WSAO). We employed a fast WSAO algorithm that enabled wavefront correction in <2 seconds by iterating the mirror shape at the speed of OCT B-scans rather than volumes. Also, we contrasted ~7° field-of-view OCTA angiograms acquired in the periphery with and without WSAO correction. On average, WSAO improved the sharpness of microvasculature by 65% in healthy and 38% in diseased eyes. Preliminary observations demonstrated that the location of 7° images could be identified directly from the wide field-of-view angiogram. A pilot study on a normal subject and patients with diabetic retinopathy showed the impact of utilizing WSAO for OCTA when visualizing peripheral vasculature pathologies. PMID:28059209

Value of C-Arm Cone Beam Computed Tomography Image Fusion in Maximizing the Versatility of Endovascular Robotics.

PubMed

Chinnadurai, Ponraj; Duran, Cassidy; Al-Jabbari, Odeaa; Abu Saleh, Walid K; Lumsden, Alan; Bismuth, Jean

2016-01-01

To report our initial experience and highlight the value of using intraoperative C-arm cone beam computed tomography (CT; DynaCT(®)) image fusion guidance along with steerable robotic endovascular catheter navigation to optimize vessel cannulation. Between May 2013 and January 2015, all patients who underwent endovascular procedures using DynaCT image fusion technique along with Hansen Magellan vascular robotic catheter were included in this study. As a part of preoperative planning, relevant vessel landmarks were electronically marked in contrast-enhanced multi-slice computed tomography images and stored. At the beginning of procedure, an intraoperative noncontrast C-arm cone beam CT (syngo DynaCT(®), Siemens Medical Solutions USA Inc.) was acquired in the hybrid suite. Preoperative images were then coregistered to intraoperative DynaCT images using aortic wall calcifications and bone landmarks. Stored landmarks were then overlaid on 2-dimensional (2D) live fluoroscopic images as virtual markers that are updated in real-time with C-arm, table movements and image zoom. Vascular access and robotic catheter (Magellan(®), Hansen Medical) was setup per standard. Vessel cannulation was performed based on electronic virtual markers on live fluoroscopy using robotic catheter. The impact of 3-dimensional (3D) image fusion guidance on robotic vessel cannulation was evaluated retrospectively, by assessing quantitative parameters like number of angiograms acquired before vessel cannulation and qualitative parameters like accuracy of vessel ostium and centerline markers. All 17 vessels were cannulated successfully in 14 patients' attempted using robotic catheter and image fusion guidance. Median vessel diameter at origin was 5.4 mm (range, 2.3-13 mm), whereas 12 of 17 (70.6%) vessels had either calcified and/or stenosed origin from parent vessel. Nine of 17 vessels (52.9 %) were cannulated without any contrast injection. Median number of angiograms required before cannulation was 0 (range, 0-2). On qualitative assessment, 14 of 15 vessels (93.3%) had grade = 1 accuracy (guidewire inside virtual ostial marker). Fourteen of 14 vessels had grade = 1 accuracy (virtual centerlines that matched with the actual vessel trajectory during cannulation). In this small series, the experience of using DynaCT image fusion guidance together with a steerable endovascular robotic catheter indicates that such image fusion strategies can enhance intraoperative 2D fluoroscopy by bringing preoperative 3D information about vascular stenosis and/or calcification, angulation, and take off from main vessel thereby facilitating ultimate vessel cannulation. Copyright © 2016 Elsevier Inc. All rights reserved.

A Cross-Sectional Cohort Study of Cerebrovascular Disease and Late Effects After Radiation Therapy for Craniopharyngioma.

PubMed

Lo, Andrea C; Howard, A Fuchsia; Nichol, Alan; Hasan, Haroon; Martin, Monty; Heran, Manraj; Goddard, Karen

2016-05-01

The study objective was to describe radiation-induced vascular abnormalities, stroke prevalence, and stroke risk factors in survivors of childhood craniopharyngioma. Twenty survivors of childhood craniopharyngioma who received radiotherapy (RT) were included in the study. A clinical history, quality of life assessment, cognitive functioning assessment, magnetic resonance angiogram or computed tomography angiogram, fasting lipid profile, and fasting glucose or hemoglobin A1c test were obtained. Median age at diagnosis was 10.3 years and median age at time of study was 29.0 years. Vascular abnormalities were detected in six (32%) of 19 patients' angiograms (vascular stenosis, decreased artery size, aneurysm, cavernoma, and small vessel disease). Five (25%) of 20 patients experienced a stroke after RT. Median time since RT was 27.8 versus 9.1 years in patients with versus without vascular abnormalities (P = 0.02). A low level of high-density lipoproteiin (HDL) was present in 100% (5/5) of patients who had a post-RT stroke as compared with 13% (2/15) of patients who did not have any post-RT stroke (P = 0.02). Previous stroke had occurred in 0% (0/5) of patients receiving growth hormone (GH) replacement at the time of study, compared to 40% (6/15) of patients who were not receiving GH replacement (P = 0.09). Patients with craniopharyngioma treated with RT have a high prevalence of stroke and vascular abnormalities, particularly those with low HDL and longer duration of time since RT. There is a trend to suggest that continual GH replacement may reduce the risk of stroke. These patients should undergo careful monitoring and aggressive modification of stroke risk factors. © 2016 Wiley Periodicals, Inc.

99mTc-MAA/ 90Y-Bremsstrahlung SPECT/CT after simultaneous Tc-MAA/90Y-microsphere injection for immediate treatment monitoring and further therapy planning for radioembolization.

PubMed

Ahmadzadehfar, Hojjat; Sabet, Amir; Muckle, Marianne; Wilhelm, Kai; Reichmann, Karl; Biersack, Hans-Jürgen; Ezziddin, Samer

2011-07-01

An angiographic evaluation combined with (99m)Tc-macroaggregated albumin (Tc-MAA) scanning should precede the treatment of any selected candidates for radioembolization (RE) of the liver. If the tumours in one liver lobe have not been targeted in the test angiogram, it should be repeated. However, in a few cases treatment of one liver lobe or at least some segments is safe and feasible and performing a repeated test angiogram with Tc-MAA (Re-MAA) in a separate session leads to more radiation exposure and could be time consuming. Our aim was to evaluate the feasibility of concurrent RE of a part of the liver and therapy planning for another region by simultaneous injection of the Tc-MAA and (90)Y-microspheres in two different locations in the therapy session. Tc-MAA and bremsstrahlung (BS) single photon emission computed tomography (SPECT)/CT were performed separately in an effort to distinguish between the distributions of these two different radiopharmaceuticals. RE was combined with a simultaneous second test angiogram of another lobe or segments in the same session in six patients [44-70 years; five women (83%)]. Five patients suffered from colorectal carcinoma (CRC) and one from ovarian cancer. Tc-MAA and BS SPECT/CT were performed for all cases. Post-therapeutic Tc-MAA SPECT/CT showed in all patients only the distribution of Tc-MAA without any detectable BS. Evaluation of (90)Y-microsphere distribution was not always possible in the post-therapeutic BS scan performed 24 h later due to remaining Tc-MAA radiation. However, scans performed at 48 h post-intervention no longer showed any Tc-MAA "contamination". Combining RE and Re-MAA is feasible in appropriately selected patients.

Psychiatric Characteristics of the Cardiac Outpatients with Chest Pain

PubMed Central

Lee, Jea-Geun; Kim, Song-Yi; Kim, Ki-Seok; Joo, Seung-Jae

2016-01-01

Background and Objectives A cardiologist's evaluation of psychiatric symptoms in patients with chest pain is rare. This study aimed to determine the psychiatric characteristics of patients with and without coronary artery disease (CAD) and explore their relationship with the intensity of chest pain. Subjects and Methods Out of 139 consecutive patients referred to the cardiology outpatient department, 31 with atypical chest pain (heartburn, acid regurgitation, dyspnea, and palpitation) were excluded and 108 were enrolled for the present study. The enrolled patients underwent complete numerical rating scale of chest pain and the symptom checklist for minor psychiatric disorders at the time of first outpatient visit. The non-CAD group consisted of patients with a normal stress test, coronary computed tomography angiogram, or coronary angiogram, and the CAD group included those with an abnormal coronary angiogram. Results Nineteen patients (17.6%) were diagnosed with CAD. No differences in the psychiatric characteristics were observed between the groups. "Feeling tense", "self-reproach", and "trouble falling asleep" were more frequently observed in the non-CAD (p=0.007; p=0.046; p=0.044) group. In a multiple linear regression analysis with a stepwise selection, somatization without chest pain in the non-CAD group and hypochondriasis in the CAD group were linearly associated with the intensity of chest pain (β=0.108, R2=0.092, p=0.004; β= -0.525, R2=0.290, p=0.010). Conclusion No differences in psychiatric characteristics were observed between the groups. The intensity of chest pain was linearly associated with somatization without chest pain in the non-CAD group and inversely linearly associated with hypochondriasis in the CAD group. PMID:27014347

Pseudoaneurysm embolization and vasopressin infusion for lower gastrointestinal bleeding due to recurrence of urinary bladder carcinoma.

PubMed

Kakizawa, Hideaki; Toyota, Naoyuki; Mita, Koji; Fujimura, Yoshio; Hieda, Masashi; Hirai, Nobuhiko; Tachikake, Toshihiro; Ito, Katsuhide

2006-05-01

We report a case that was successfully treated for massive lower gastrointestinal (LGI) bleeding due to a recurrent urinary bladder carcinoma. Treatment consisted of combination therapy including embolization of an inferior gluteal artery (IGA) pseudoaneurysm and low-dose arterial vasopressin infusion via a sigmoid artery (SA). A 57-year-old man presented with life-threatening sudden, massive LGI bleeding due to an obturator lymph node (LN) metastasis from a urinary bladder carcinoma. Computed tomography showed that the LN recurrence had invaded all the way to the sigmoid colon, and there was a pseudoaneurysm with extravasation inside the recurrence. An angiogram revealed a left IGA pseudoaneurysm. We therefore excluded the pseudoaneurysm by embolization with microcoils. Following this treatment the bleeding decreased, but intermittent LGI bleeding continued. Endoscopic examination showed the tumor with a huge ulcer inside the colonic lumen, and continuous oozing was confirmed. A second angiogram showed no recurrence of the IGA pseudoaneurysm and no apparent findings of bleeding. Then a 3F microcatheter was placed in the SA selectively using a coaxial catheter system, and vasopressin was infused at a rate 0.05 U/min for 12 h. Bleeding completely ceased 2 days later. There were no signs of ischemic gastrointestinal complications. Massive LGI bleeding has not recurred in 5 months.

Medications as causes of intraluminal hyperdensities: what radiologists need to know.

PubMed

Sin, Francesca Nga Yee; Tsang, Jane Pui Ki; Siu, Kwong Lok; Ma, Johnny Ka Fai; Yung, Alfred Wei Tak

2012-07-01

In computed tomography (CT) angiogram or some dedicated CT studies of the abdomen, the use of positive enteric contrast should be avoided as its presence could decrease the sensitivity of the test. There are, however, cases of CT scans with unexpected hyperdense intraluminal contents detected due to the use of certain oral or rectal medications. Reports on medications as causes of intraluminal hyperdensities are sparse in the English literature. We have studied several commonly used medications and revealed that many drugs appear hyperdense in CT scans. The presence of unexpected intraluminal hyperdensities can potentially cause erroneous interpretation of images and in some cases decrease the sensitivity of the test. The hyperdense bowel contents may be mistaken as acute hemorrhage in CT angiogram for detection of GI bleeding. Active GI bleeding, presented as intraluminal extravasation of contrast material, can also be obscured. Certain intra-abdominal pathologies could be masked, for example, in plain CT scan for detection of urinary tract stones or in contrast CT study for suspected bowel ischaemia. It is important for radiologists and clinicians to be aware of this situation in order to prevent misinterpretation of images and to select the most appropriate imaging modality when such unexpected intraluminal hyperdensities are encountered. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Amyloidosis and spontaneous hepatic bleeding, transcatheter therapy for hepatic parenchymal bleeding with massive intraperitoneal hemorrhage: a case report and review of the literature.

PubMed

Mousa, Albeir Y; Abu-Halimah, Shadi; Alhalbouni, Saadi; Hass, Stephen M; Yang, Calvin; Gill, Gurpreet; AbuRahma, Ali F; Bates, Mark

2014-10-01

Hepatic hemorrhage can be devastating, especially in patients with underlying hepatic pathology. This is a case report of a 50-year-old man who presented to the emergency room with Stage 3 shock as evidenced by a systolic blood pressure of 90 mmHg, a heart rate of 125 beats per minute, respiration of 32, with delayed capillary refill and agitation. At this time, he was found to have a massive spontaneous intra-abdominal hemorrhage with an advanced stage of amyloidosis with multiple organ malfunctions. The initial diagnosis was based on an abdominal computed tomography scan and the patient was taken expeditiously to a hybrid angiography suite for a celiac angiogram. An intraoperative diagnosis of extravasation from amyloid related vasculopathy was made based on the angiographic appearance of hepatic circulation. Coil embolization of the feeding branch of the bleeder was achieved using the interlock coil system and a completion angiogram was done showing complete cessation of active bleeding. The postoperative phase was uneventful and the patient was discharged home on postoperative day three. His postoperative visit at five months later was unremarkable. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Usefulness of Cone-Beam Computed Tomography and Automatic Vessel Detection Software in Emergency Transarterial Embolization.

PubMed

Carrafiello, Gianpaolo; Ierardi, Anna Maria; Duka, Ejona; Radaelli, Alessandro; Floridi, Chiara; Bacuzzi, Alessandro; de Bucourt, Maximilian; De Marchi, Giuseppe

2016-04-01

This study was designed to evaluate the utility of dual phase cone beam computed tomography (DP-CBCT) and automatic vessel detection (AVD) software to guide transarterial embolization (TAE) of angiographically challenging arterial bleedings in emergency settings. Twenty patients with an arterial bleeding at computed tomography angiography and an inconclusive identification of the bleeding vessel at the initial 2D angiographic series were included. Accuracy of DP-CBCT and AVD software were defined as the ability to detect the bleeding site and the culprit arterial bleeder, respectively. Technical success was defined as the correct positioning of the microcatheter using AVD software. Clinical success was defined as the successful embolization. Total volume of iodinated contrast medium and overall procedure time were registered. The bleeding site was not detected by initial angiogram in 20% of cases, while impossibility to identify the bleeding vessel was the reason for inclusion in the remaining cases. The bleeding site was detected by DP-CBCT in 19 of 20 (95%) patients; in one case CBCT-CT fusion was required. AVD software identified the culprit arterial branch in 18 of 20 (90%) cases. In two cases, vessel tracking required manual marking of the candidate arterial bleeder. Technical success was 95%. Successful embolization was achieved in all patients. Mean contrast volume injected for each patient was 77.5 ml, and mean overall procedural time was 50 min. C-arm CBCT and AVD software during TAE of angiographically challenging arterial bleedings is feasible and may facilitate successful embolization. Staff training in CBCT imaging and software manipulation is necessary.

Myocardial infarction with Moyamoya disease and pituitary gigantism in a young female patient.

PubMed

Ahn, Y K; Jeong, M H; Bom, H S; Park, J C; Kim, J K; Chung, D J; Chung, M Y; Cho, J G; Kang, J C

1999-08-01

Myocardial infarction is very rare in young female patients with systemic vascular disorders. Moyamoya disease is a cerebrovascular disease associated with an abnormal vascular network. This report presents a 19-year-old female patient who suffered from chest pain and exertional dyspnea for 2 months prior to admission. She had a history of Moyamoya disease and pituitary gigantism since childhood. Her ejection fraction on echocardiogram was 20% and a perfusion defect with partial reversibility in the anterior wall was demonstrated on stress single photon emission computed tomography (SPECT). Diagnostic coronary angiogram revealed critical stenosis in the middle left anterior descending artery, which was treated by coronary stenting. Her subjective symptoms were relieved and the perfusion defect seen on SPECT decreased after coronary intervention.

Noninvasive coronary artery angiography using electron beam computed tomography

NASA Astrophysics Data System (ADS)

Rumberger, John A.; Rensing, Benno J.; Reed, Judd E.; Ritman, Erik L.; Sheedy, Patrick F., II

1996-04-01

Electron beam computed tomography (EBCT), also known as ultrafast-CT or cine-CT, uses a unique scanning architecture which allows for multiple high spatial resolution electrocardiographic triggered images of the beating heart. A recent study has demonstrated the feasibility of qualitative comparisons between EBCT derived 3D coronary angiograms and invasive angiography. Stenoses of the proximal portions of the left anterior descending and right coronary arteries were readily identified, but description of atherosclerotic narrowing in the left circumflex artery (and distal epicardial disease) was not possible with any degree of confidence. Although these preliminary studies support the notion that this approach has potential, the images overall were suboptimal for clinical application as an adjunct to invasive angiography. Furthermore, these studies did not examine different methods of EBCT scan acquisition, tomographic slice thicknesses, extent of scan overlap, or other segmentation, thresholding, and interpolation algorithms. Our laboratory has initiated investigation of these aspects and limitations of EBCT coronary angiography. Specific areas of research include defining effects of cardiac orientation; defining the effects of tomographic slice thickness and intensity (gradient) versus positional (shaped based) interpolation; and defining applicability of imaging each of the major epicardial coronary arteries for quantitative definition of vessel size, cross-sectional area, taper, and discrete vessel narrowing.

A quantitative evaluation of the three dimensional reconstruction of patients' coronary arteries.

PubMed

Klein, J L; Hoff, J G; Peifer, J W; Folks, R; Cooke, C D; King, S B; Garcia, E V

1998-04-01

Through extensive training and experience angiographers learn to mentally reconstruct the three dimensional (3D) relationships of the coronary arterial branches. Graphic computer technology can assist angiographers to more quickly visualize the coronary 3D structure from limited initial views and then help to determine additional helpful views by predicting subsequent angiograms before they are obtained. A new computer method for facilitating 3D reconstruction and visualization of human coronary arteries was evaluated by reconstructing biplane left coronary angiograms from 30 patients. The accuracy of the reconstruction was assessed in two ways: 1) by comparing the vessel's centerlines of the actual angiograms with the centerlines of a 2D projection of the 3D model projected into the exact angle of the actual angiogram; and 2) by comparing two 3D models generated by different simultaneous pairs on angiograms. The inter- and intraobserver variability of reconstruction were evaluated by mathematically comparing the 3D model centerlines of repeated reconstructions. The average absolute corrected displacement of 14,662 vessel centerline points in 2D from 30 patients was 1.64 +/- 2.26 mm. The average corrected absolute displacement of 3D models generated from different biplane pairs was 7.08 +/- 3.21 mm. The intraobserver variability of absolute 3D corrected displacement was 5.22 +/- 3.39 mm. The interobserver variability was 6.6 +/- 3.1 mm. The centerline analyses show that the reconstruction algorithm is mathematically accurate and reproducible. The figures presented in this report put these measurement errors into clinical perspective showing that they yield an accurate representation of the clinically relevant information seen on the actual angiograms. These data show that this technique can be clinically useful by accurately displaying in three dimensions the complex relationships of the branches of the coronary arterial tree.

Usefulness of Cone-Beam Computed Tomography and Automatic Vessel Detection Software in Emergency Transarterial Embolization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carrafiello, Gianpaolo, E-mail: gcarraf@gmail.com; Ierardi, Anna Maria, E-mail: amierardi@yahoo.it; Duka, Ejona, E-mail: ejonaduka@hotmail.com

BackgroundThis study was designed to evaluate the utility of dual phase cone beam computed tomography (DP-CBCT) and automatic vessel detection (AVD) software to guide transarterial embolization (TAE) of angiographically challenging arterial bleedings in emergency settings.MethodsTwenty patients with an arterial bleeding at computed tomography angiography and an inconclusive identification of the bleeding vessel at the initial 2D angiographic series were included. Accuracy of DP-CBCT and AVD software were defined as the ability to detect the bleeding site and the culprit arterial bleeder, respectively. Technical success was defined as the correct positioning of the microcatheter using AVD software. Clinical success was definedmore » as the successful embolization. Total volume of iodinated contrast medium and overall procedure time were registered.ResultsThe bleeding site was not detected by initial angiogram in 20 % of cases, while impossibility to identify the bleeding vessel was the reason for inclusion in the remaining cases. The bleeding site was detected by DP-CBCT in 19 of 20 (95 %) patients; in one case CBCT-CT fusion was required. AVD software identified the culprit arterial branch in 18 of 20 (90 %) cases. In two cases, vessel tracking required manual marking of the candidate arterial bleeder. Technical success was 95 %. Successful embolization was achieved in all patients. Mean contrast volume injected for each patient was 77.5 ml, and mean overall procedural time was 50 min.ConclusionsC-arm CBCT and AVD software during TAE of angiographically challenging arterial bleedings is feasible and may facilitate successful embolization. Staff training in CBCT imaging and software manipulation is necessary.« less

Recanalization after successful occlusion by transcatheter arterial embolization with N-butyl cyanoacrylate for traumatic splenic artery injury.

PubMed

Ishikawa, Masaki; Kakizawa, Hideaki; Yamasaki, Wataru; Date, Syuji; Hieda, Masashi; Kajiwara, Kenji; Awai, Kazuo

2011-12-01

A 70-year-old male with advanced pancreatic cancer went into shock after sustaining a traumatic abdominal injury. Computed tomography (CT) showed a hematoma with extravasation around the pancreas and hemorrhagic ascites. After direct catheterization failed due to angiospasm, the ruptured splenic artery was successfully occluded by transcatheter arterial embolization (TAE) using an N-butyl cyanoacrylate (NBCA)-lipiodol mixture and the patient recovered from shock without complications. A follow-up CT obtained 20 days later showed a recurrent splenic artery pseudoaneurysm without extravasation. A repeat angiogram demonstrated recanalization of the splenic artery and pseudoaneurysm via antegrade. We embolized the recanalized pseudoaneurysm using metallic coils for isolation. Our experience indicates that adequate concentration and volume of the NBCA-lipiodol mixture should be considered depending on the vascular spasm in a patient with hypovolemic shock.

Computer-aided detection of acute pulmonary embolism with 64-slice multi-detector row computed tomography: impact of the scanning conditions and overall image quality in the detection of peripheral clots.

PubMed

Dewailly, Marion; Rémy-Jardin, Martine; Duhamel, Alain; Faivre, Jean-Baptiste; Pontana, François; Deken, Valérie; Bakai, Anne-Marie; Remy, Jacques

2010-01-01

To evaluate the performance of a computer-aided detection (CAD) system for diagnosing peripheral acute pulmonary embolism (PE) with a 64-slice multi-detector row computed tomography (CT). Two radiologists investigated the accuracy of a software aimed at detecting peripheral clots (PECAD prototype, version 7; Siemens Medical Systems, Forchheim, Germany) by applying this tool for the analysis of the pulmonary arterial bed of 74 CT angiograms obtained with 64-slice dual-source CT (Definition; Siemens Medical Systems). These cases were retrospectively selected from a database of CT studies performed on the same CT unit, with a similar collimation (64 x 0.6 mm) and similar injection protocols. Patient selection was based on a variety of (1) scanning conditions, namely, nongated (n = 30), electrocardiography-gated (n = 30), and dual-energy CT angiograms (n = 14), and (2) image quality (IQ), namely, scans of excellent IQ (n = 53) and lower IQ due to lower levels of arterial enhancement and/or presence of noise (n = 21). The standard of truth was based on the 2 radiologists' consensus reading and the results of CAD. The software detected 80 of 93 peripheral clots present in the 21 patients (42 segmental and 38 subsegmental clots). The overall sensitivity (95% confidence interval) of the CAD tool was 86% (77%-92%) for detecting peripheral clots, 78% (64.5%-88%) at the segmental level and 97% (85.5%-99.9%) at the subsegmental level. Assuming normal vascular anatomy with 20 segmental and 40 subsegmental arteries, overall specificity and positive and negative predictive values (95% confidence interval) of the software were 91.8% (91%-92.6%), 18.4% (15%-22.4%), and 99.7% (99.5%-99.8%), respectively. A mean of 5.4 false positives was found per patient (total, 354 false positives), mainly linked to the presence of perivascular connective tissue (n = 119; 34%) and perivascular airspace consolidation (n = 97; 27%). The sensitivities (95% confidence interval) for the CAD tool were 91% (69.8%-99.3%) for dual-energy, 87% (59.3%-93.2%) for electrocardiography-gated, and 87% (73.5%-95.3%) for nongated scans (P > 0.05). No significant difference was found in the sensitivity of the CAD software when comparing the scans according to the scanning conditions and image quality. The evaluated CAD software has a good sensitivity in detecting peripheral PE, which is not influenced by the scanning conditions or the overall image quality.

Quantification of choroidal neovascularization vessel length using optical coherence tomography angiography

NASA Astrophysics Data System (ADS)

Gao, Simon S.; Liu, Li; Bailey, Steven T.; Flaxel, Christina J.; Huang, David; Li, Dengwang; Jia, Yali

2016-07-01

Quantification of choroidal neovascularization (CNV) as visualized by optical coherence tomography angiography (OCTA) may have importance clinically when diagnosing or tracking disease. Here, we present an automated algorithm to quantify the vessel skeleton of CNV as vessel length. Initial segmentation of the CNV on en face angiograms was achieved using saliency-based detection and thresholding. A level set method was then used to refine vessel edges. Finally, a skeleton algorithm was applied to identify vessel centerlines. The algorithm was tested on nine OCTA scans from participants with CNV and comparisons of the algorithm's output to manual delineation showed good agreement.

Digital image processing of vascular angiograms

NASA Technical Reports Server (NTRS)

Selzer, R. H.; Beckenbach, E. S.; Blankenhorn, D. H.; Crawford, D. W.; Brooks, S. H.

1975-01-01

The paper discusses the estimation of the degree of atherosclerosis in the human femoral artery through the use of a digital image processing system for vascular angiograms. The film digitizer uses an electronic image dissector camera to scan the angiogram and convert the recorded optical density information into a numerical format. Another processing step involves locating the vessel edges from the digital image. The computer has been programmed to estimate vessel abnormality through a series of measurements, some derived primarily from the vessel edge information and others from optical density variations within the lumen shadow. These measurements are combined into an atherosclerosis index, which is found in a post-mortem study to correlate well with both visual and chemical estimates of atherosclerotic disease.

Giant right coronary artery aneurysm in an adult male patient with non-ST myocardial infarction.

PubMed

Halapas, Antonios; Lausberg, Henning; Gehrig, Thomas; Friedrich, Ivar; Hauptmann, Karl E

2013-01-01

The combination of a giant coronary aneurysm with multiple coronary aneurysms in adults is an extremely rare entity--especially in atherosclerotic patients, since it is most commonly associated with Kawasaki disease in children. We report an interesting case of a 59-year-old male patient with multiple atherosclerotic aneurysms of the left coronary system and a giant aneurysm of the right coronary artery. The patient was admitted to our hospital because of a non-ST myocardial infarction. Diagnosis was established by echocardiography, computed tomography angiogram, and coronary angiography. In view of the clinical symptoms and the extent of the giant right coronary aneurysm, with the associated risk of rupture, the patient was successfully treated with urgent surgical intervention. We also present a review of the current literature on this anomaly and a statistical analysis of all atherosclerotic giant coronary artery aneurysms previously reported.

Neurologic Involvement in Scleroderma en Coup de Sabre

PubMed Central

Amaral, Tiago Nardi; Marques Neto, João Francisco; Lapa, Aline Tamires; Peres, Fernando Augusto; Guirau, Caio Rodrigues; Appenzeller, Simone

2012-01-01

Localized scleroderma is a rare disease, characterized by sclerotic lesions. A variety of presentations have been described, with different clinical characteristics and specific prognosis. In scleroderma en coup de sabre (LScs) the atrophic lesion in frontoparietal area is the disease hallmark. Skin and subcutaneous are the mainly affected tissues, but case reports of muscle, cartilage, and bone involvement are frequent. These cases pose a difficult differential diagnosis with Parry-Romberg syndrome. Once considered an exclusive cutaneous disorder, the neurologic involvement present in LScs has been described in several case reports. Seizures are most frequently observed, but focal neurologic deficits, movement disorders, trigeminal neuralgia, and mimics of hemiplegic migraines have been reported. Computed tomography and magnetic resonance imaging have aided the characterization of central nervous system lesions, and cerebral angiograms have pointed to vasculitis as a part of disease pathogenesis. In this paper we describe the clinical and radiologic aspects of neurologic involvement in LScs. PMID:22319646

Knowledge Translation of the PERC Rule for Suspected Pulmonary Embolism: A Blueprint for Reducing the Number of CT Pulmonary Angiograms.

PubMed

Drescher, Michael J; Fried, Jeremy; Brass, Ryan; Medoro, Amanda; Murphy, Timothy; Delgado, João

2017-10-01

Computerized decision support decreases the number of computed tomography pulmonary angiograms (CTPA) for pulmonary embolism (PE) ordered in emergency departments, but it is not always well accepted by emergency physicians. We studied a department-endorsed, evidence-based clinical protocol that included the PE rule-out criteria (PERC) rule, multi-modal education using principles of knowledge translation (KT), and clinical decision support embedded in our order entry system, to decrease the number of unnecessary CTPA ordered. We performed a historically controlled observational before-after study for one year pre- and post-implementation of a departmentally-endorsed protocol. We included patients > 18 in whom providers suspected PE and who did not have a contraindication to CTPA. Providers entered clinical information into a diagnostic pathway via computerized order entry. Prior to protocol implementation, we provided education to ordering providers. The primary outcome measure was the number of CTPA ordered per 1,000 visits one year before vs. after implementation. CTPA declined from 1,033 scans for 98,028 annual visits (10.53 per 1,000 patient visits (95% CI [9.9-11.2]) to 892 scans for 101,172 annual visits (8.81 per 1,000 patient visits (95% CI [8.3-9.4]) p<0.001. The absolute reduction in PACT ordered was 1.72 per 1,000 visits (a 16% reduction). Patient characteristics were similar for both periods. Knowledge translation clinical decision support using the PERC rule significantly reduced the number of CTPA ordered.

Calcium score of coronary artery stratifies the risk of obstructive coronary artery diseases.

PubMed

Ibrahim, O; Oteh, M; Anwar, I R; Che Hassan, H H; Choor, C K; Hamzaini, A H; Rahman, M M

2013-01-01

Coronary heart disease is a major health problem in Malaysia with high morbidity and mortality. Common primary screening tool of cardiovascular risk stratification is exercise treadmill test (ETT). This communication is to determine the performance of coronary artery calcium score a new method to stratify the presence of obstructive coronary artery disease (CAD) in comparison to traditional ETT in patients having coronary artery diseases. Patients between 30 to 60 years old attended the ETT to screen for ischemic heart disease were recruited for Agatston coronary artery calcium score (CACS) of multi-sliced computed tomography (MSCT). Subsequently all patients underwent a full MSCT coronary angiography. The major determinant was the state of CAD whether obstructive (50% stenosis or more) or non-obstructive (less than 50% stenosis). All patients diagnosed with obstructive CAD on MSCT coronary angiogram were subjected to invasive coronary angiogram (ICA) to confirm the findings and planned the need for revascularization. The CACS was 100% sensitivity and 97.5% specificity in detecting obstructive CAD at the optimal cut-off value of 106.5 and above. The positive predictive value (PPV) at CACS ≥ 106 was 71.4% and the negative predictive value (NPV) was consistent at 100%. Compare to ETT, the CACS discriminative value and diagnostic performance was much better (PPV 71.4% vs. 45.5%), respectively. CACS can be a good diagnostic screening tool in patients suspected of CAD, and particularly within the non-diagnostic ETT subgroup with low to moderate cardiovascular risks.

Choriocapillaris and Choroidal Microvasculature Imaging with Ultrahigh Speed OCT Angiography

PubMed Central

Choi, WooJhon; Mohler, Kathrin J.; Potsaid, Benjamin; Lu, Chen D.; Liu, Jonathan J.; Jayaraman, Vijaysekhar; Cable, Alex E.; Duker, Jay S.; Huber, Robert; Fujimoto, James G.

2013-01-01

We demonstrate in vivo choriocapillaris and choroidal microvasculature imaging in normal human subjects using optical coherence tomography (OCT). An ultrahigh speed swept source OCT prototype at 1060 nm wavelengths with a 400 kHz A-scan rate is developed for three-dimensional ultrahigh speed imaging of the posterior eye. OCT angiography is used to image three-dimensional vascular structure without the need for exogenous fluorophores by detecting erythrocyte motion contrast between OCT intensity cross-sectional images acquired rapidly and repeatedly from the same location on the retina. En face OCT angiograms of the choriocapillaris and choroidal vasculature are visualized by acquiring cross-sectional OCT angiograms volumetrically via raster scanning and segmenting the three-dimensional angiographic data at multiple depths below the retinal pigment epithelium (RPE). Fine microvasculature of the choriocapillaris, as well as tightly packed networks of feeding arterioles and draining venules, can be visualized at different en face depths. Panoramic ultra-wide field stitched OCT angiograms of the choriocapillaris spanning ∼32 mm on the retina show distinct vascular structures at different fundus locations. Isolated smaller fields at the central fovea and ∼6 mm nasal to the fovea at the depths of the choriocapillaris and Sattler's layer show vasculature structures consistent with established architectural morphology from histological and electron micrograph corrosion casting studies. Choriocapillaris imaging was performed in eight healthy volunteers with OCT angiograms successfully acquired from all subjects. These results demonstrate the feasibility of ultrahigh speed OCT for in vivo dye-free choriocapillaris and choroidal vasculature imaging, in addition to conventional structural imaging. PMID:24349078

Choriocapillaris and choroidal microvasculature imaging with ultrahigh speed OCT angiography.

PubMed

Choi, WooJhon; Mohler, Kathrin J; Potsaid, Benjamin; Lu, Chen D; Liu, Jonathan J; Jayaraman, Vijaysekhar; Cable, Alex E; Duker, Jay S; Huber, Robert; Fujimoto, James G

2013-01-01

We demonstrate in vivo choriocapillaris and choroidal microvasculature imaging in normal human subjects using optical coherence tomography (OCT). An ultrahigh speed swept source OCT prototype at 1060 nm wavelengths with a 400 kHz A-scan rate is developed for three-dimensional ultrahigh speed imaging of the posterior eye. OCT angiography is used to image three-dimensional vascular structure without the need for exogenous fluorophores by detecting erythrocyte motion contrast between OCT intensity cross-sectional images acquired rapidly and repeatedly from the same location on the retina. En face OCT angiograms of the choriocapillaris and choroidal vasculature are visualized by acquiring cross-sectional OCT angiograms volumetrically via raster scanning and segmenting the three-dimensional angiographic data at multiple depths below the retinal pigment epithelium (RPE). Fine microvasculature of the choriocapillaris, as well as tightly packed networks of feeding arterioles and draining venules, can be visualized at different en face depths. Panoramic ultra-wide field stitched OCT angiograms of the choriocapillaris spanning ∼32 mm on the retina show distinct vascular structures at different fundus locations. Isolated smaller fields at the central fovea and ∼6 mm nasal to the fovea at the depths of the choriocapillaris and Sattler's layer show vasculature structures consistent with established architectural morphology from histological and electron micrograph corrosion casting studies. Choriocapillaris imaging was performed in eight healthy volunteers with OCT angiograms successfully acquired from all subjects. These results demonstrate the feasibility of ultrahigh speed OCT for in vivo dye-free choriocapillaris and choroidal vasculature imaging, in addition to conventional structural imaging.

Phenylpropanolamine and cerebral hemorrhage

DOE Office of Scientific and Technical Information (OSTI.GOV)

McDowell, J.R.; LeBlanc, H.J.

1985-05-01

Computerized tomography, carotid angiograms, and arteriography were used to diagnose several cases of cerebral hemorrhage following the use of phenylpropanolamine. The angiographic picture in one of the three cases was similar to that previously described in association with amphetamine abuse and pseudoephedrine overdose, both substances being chemically and pharmacologically similar to phenylpropanolamine. The study suggests that the arterial change responsible for symptoms may be due to spasm rather than arteriopathy. 14 references, 5 figures.

Intentional left subclavian artery coverage during thoracic endovascular aortic repair for traumatic aortic injury.

PubMed

McBride, Cameron L; Dubose, Joseph J; Miller, Charles C; Perlick, Alexa P; Charlton-Ouw, Kristofer M; Estrera, Anthony L; Safi, Hazim J; Azizzadeh, Ali

2015-01-01

Thoracic endovascular aortic repair (TEVAR) is widely used for treatment of traumatic aortic injury (TAI). Stent graft coverage of the left subclavian artery (LSA) may be required in up to 40% of patients. We evaluated the long-term effects of intentional LSA coverage (LSAC) on symptoms and return to normal activity in TAI patients compared with a similarly treated group whose LSA was uncovered (LSAU). Patients were identified from a prospective institutional trauma registry between September 2005 and July 2012. TAI was confirmed using computed tomography angiography. The electronic medical records, angiograms, and computed tomography angiograms were reviewed in a retrospective fashion. In-person or telephone interviews were conducted using the SF-12v2 (Quality Metrics, Lincoln, RI) to assess quality of life. An additional questionnaire was used to assess specific LSA symptoms and the ability to return to normal activities. Data were analyzed by Spearman rank correlation and multiple linear and logistic regression analysis with appropriate transformations using SAS software (SAS Institute, Cary, NC). During the study period, 82 patients (57 men; mean age 40.5 ± 20 years, mean Injury Severity Score, 34 ± 10.0) underwent TEVAR for treatment of TAI. Among them, LSAC was used in 32 (39.5%) and LSAU in 50. A group of the LSAU patients (n = 22) served as matched controls in the analysis. We found no statistically significant difference in SF-12v2 physical health scores (ρ = -0.08; P = .62) between LSAC and LSAU patients. LSAC patients had slightly better mental health scores (ρ = 0.62; P = .037) than LSAU patients. LSAC patients did not have an increased likelihood of experiencing pain (ρ = -0.0056; P = .97), numbness (ρ = -0.12; P = .45), paresthesia (ρ = -0.11; P = .48), fatigue (ρ = -0.066; P = .69), or cramping (ρ = -0.12; P = .45). We found no difference between groups in the ability to return to activities. The mean follow-up time was 3.35 years. Six LSAC patients (19%) died during the follow-up period of unrelated causes. Intentional LSAC during TEVAR for TAI appears safe, without compromising mental or physical health outcomes. Furthermore, LSAC does not increase the long-term risk of upper extremity symptoms or impairment of normal activities. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Uniform enhancement of optical micro-angiography images using Rayleigh contrast-limited adaptive histogram equalization.

PubMed

Yousefi, Siavash; Qin, Jia; Zhi, Zhongwei; Wang, Ruikang K

2013-02-01

Optical microangiography is an imaging technology that is capable of providing detailed functional blood flow maps within microcirculatory tissue beds in vivo. Some practical issues however exist when displaying and quantifying the microcirculation that perfuses the scanned tissue volume. These issues include: (I) Probing light is subject to specular reflection when it shines onto sample. The unevenness of the tissue surface makes the light energy entering the tissue not uniform over the entire scanned tissue volume. (II) The biological tissue is heterogeneous in nature, meaning the scattering and absorption properties of tissue would attenuate the probe beam. These physical limitations can result in local contrast degradation and non-uniform micro-angiogram images. In this paper, we propose a post-processing method that uses Rayleigh contrast-limited adaptive histogram equalization to increase the contrast and improve the overall appearance and uniformity of optical micro-angiograms without saturating the vessel intensity and changing the physical meaning of the micro-angiograms. The qualitative and quantitative performance of the proposed method is compared with those of common histogram equalization and contrast enhancement methods. We demonstrate that the proposed method outperforms other existing approaches. The proposed method is not limited to optical microangiography and can be used in other image modalities such as photo-acoustic tomography and scanning laser confocal microscopy.

Efficacy of a Self-Expandable Porous Stent as the Sole Curative Treatment for Extracranial Carotid Pseudoaneurysms.

PubMed

Chen, Peng Roc; Edwards, Nancy J; Sanzgiri, Aditya; Day, Arthur L

2016-04-01

Extracranial carotid pseudoaneurysms are uncommon vascular lesions. Even with conservative management complications can happen, such as delayed cerebral embolization or symptoms due to flow limitation. Although endovascular therapy can be curative, literature demonstrating a preferred technique is scant. Our goal was to evaluate the use of 1 technique only-the deployment of overlapping self-expandable porous stents-to treat a series of extracranial carotid pseudoaneurysms. From 2008 to 2014, 14 consecutive cases of symptomatic extracranial carotid pseudoaneurysms were managed with single or multilayer porous stents at our institution. Each patient underwent a standardized angiographic follow-up at 6 months. Twelve patients also received a follow-up computed tomography angiogram at 12 months, and yearly thereafter (median radiographic follow-up, 38 months). The total clinical follow-up period ranged between 6 and 69 months (median, 46 months). In our series, each of the extracranial carotid pseudoaneurysms appeared to be the result of carotid artery dissection with associated carotid stenosis at the origin of every pseudoaneurysm. Endovascular treatment consisted of 1-3 layers of self-expandable porous stents placed without balloon angioplasty. Immediately after stenting angiographic images were notable for stagnant opacification of the pseudoaneurysm through the stent(s). All pseudoaneurysms were completely obliterated by the 6-month follow-up angiogram and remained so throughout the radiographic follow-up period. Complications were minimal, consisting of 1 patient developing a mild Horner's syndrome after treatment that resolved during clinical follow-up. Extracranial carotid pseudoaneurysms can be successfully obliterated with the use of porous, self-expandable stents. Copyright © 2016 Elsevier Inc. All rights reserved.

Endovascular Embolization of Bronchial Artery Originating from the Upper Portion of Aortic Arch in Patients with Massive Hemoptysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Sen, E-mail: jasfly77@vip.163.com; Sun, Xi-Wen, E-mail: xwsun@citiz.net; Yu, Dong, E-mail: yudong_mail@126.com

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 carotidmore » 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.« less

Multiple encephalogaleoperiosteal synangiosis for bilateral carotid artery stenosis in a 13-year-old girl: a case report.

PubMed

Inamura, Akinori; Nomura, Sadahiro; Sadahiro, Hirokazu; Oku, Takayuki; Ishihara, Hideyuki; Suzuki, Michiyasu

2016-05-01

Encephalogaleoperiosteal synangiosis (EGS) has been widely used to treat children with moyamoya disease (MMD). We present the first case of successful multiple EGS in a patient with brain ischemic disease who presented with different cerebrovascular findings from MMD. A 13-year-old girl had an increased frequency of transient ischemic attacks that affected her right extremities. Digital subtraction angiography showed tapering of the internal carotid artery (ICA). The anterior cerebral artery (ACA) and middle cerebral artery (MCA) were visible on vertebral angiogram, but not on carotid angiogram. The intact circle of Willis and lack of hypervascularity of the lenticulostriate arteries were observed. Decreased regional cerebral blood flow (CBF) in the bilateral ACA and MCA territories quantified by (123)I-N-isopropyl-p-iodoamphetamine-single photon emission computed tomography indicated the need for extracranial-intracranial bypass surgery. Multiple EGS procedures were performed instead of direct anastomosis, which is the standard procedure for intracranial ICA stenosis, because the space for the craniotomy was limited by transdural anastomosis. Despite the fact that the diagnosis of MMD was questionable, the hemispheres were well vascularized, and the neurology and CBF improved postoperatively. The preserved circle of Willis and lack of moyamoya vessels were inconsistent with the features of MMD. However, childhood onset, bilateralness, chronic intracranial ICA stenosis, and transdural anastomosis indicated the same underling pathogenicity as MMD. It is hypothesized that ICA stenosis occurred immediately proximal to the posterior communicating artery in this case. This would have produced the atypical finding of the remaining circle of Willis without growth of the basal moyamoya vessels.

Computational high-resolution heart phantoms for medical imaging and dosimetry simulations

NASA Astrophysics Data System (ADS)

Gu, Songxiang; Gupta, Rajiv; Kyprianou, Iacovos

2011-09-01

Cardiovascular disease in general and coronary artery disease (CAD) in particular, are the leading cause of death worldwide. They are principally diagnosed using either invasive percutaneous transluminal coronary angiograms or non-invasive computed tomography angiograms (CTA). Minimally invasive therapies for CAD such as angioplasty and stenting are rendered under fluoroscopic guidance. Both invasive and non-invasive imaging modalities employ ionizing radiation and there is concern for deterministic and stochastic effects of radiation. Accurate simulation to optimize image quality with minimal radiation dose requires detailed, gender-specific anthropomorphic phantoms with anatomically correct heart and associated vasculature. Such phantoms are currently unavailable. This paper describes an open source heart phantom development platform based on a graphical user interface. Using this platform, we have developed seven high-resolution cardiac/coronary artery phantoms for imaging and dosimetry from seven high-quality CTA datasets. To extract a phantom from a coronary CTA, the relationship between the intensity distribution of the myocardium, the ventricles and the coronary arteries is identified via histogram analysis of the CTA images. By further refining the segmentation using anatomy-specific criteria such as vesselness, connectivity criteria required by the coronary tree and image operations such as active contours, we are able to capture excellent detail within our phantoms. For example, in one of the female heart phantoms, as many as 100 coronary artery branches could be identified. Triangular meshes are fitted to segmented high-resolution CTA data. We have also developed a visualization tool for adding stenotic lesions to the coronaries. The male and female heart phantoms generated so far have been cross-registered and entered in the mesh-based Virtual Family of phantoms with matched age/gender information. Any phantom in this family, along with user-defined stenoses, can be used to obtain clinically realistic projection images with the Monte Carlo code penMesh for optimizing imaging and dosimetry.

Role of spiral volumetric computed tomographic scanning in the assessment of patients with clinical suspicion of pulmonary embolism and an abnormal ventilation/perfusion lung scan.

PubMed Central

van Rossum, A. B.; Treurniet, F. E.; Kieft, G. J.; Smith, S. J.; Schepers-Bok, R.

1996-01-01

BACKGROUND: A study was carried out to evaluate the potential place of spiral volumetric computed tomography (SVCT) in the diagnostic strategy for pulmonary embolism. METHODS: In a prospective study 249 patients with clinical suspicion of pulmonary embolism were evaluated with various imaging techniques. In all patients a ventilation/perfusion (V/Q) scan was performed. Seventy seven patients with an abnormal V/Q scan underwent SVCT. Pulmonary angiography was then performed in all 42 patients with a non-diagnostic V/Q scan and in three patients with a high probability V/Q scan without emboli on the SVCT scan. Patients with an abnormal perfusion scan also underwent ultrasonography of the legs for the detection of deep vein thrombosis. RESULTS: One hundred and seventy two patients (69%) had a normal V/Q scan. Forty two patients (17%) had a non-diagnostic V/Q scan, and in five of these patients pulmonary emboli were found both by SVCT and pulmonary angiography. In one patient, although SVCT showed no emboli, the angiogram was positive for pulmonary embolism. In one of the 42 patients the SVCT scan showed an embolus which was not confirmed by pulmonary angiography. The other 35 patients showed no sign of emboli. Thirty five patients (14%) had a high probability V/Q scan, and in 32 patients emboli were seen on SVCT images. Two patients had both a negative SVCT scan and a negative pulmonary angiogram. In one who had an inconclusive SVCT scan pulmonary angiography was positive. The sensitivity for pulmonary embolism was 95% and the specificity 97%; the positive and negative predicted values of SVCT were 97% and 97%, respectively. CONCLUSIONS: SVCT is a relatively noninvasive test for pulmonary embolism which is both sensitive and specific and which may serve as an alternative to ventilation scintigraphy and possibly to pulmonary angiography in the diagnostic strategy for pulmonary embolism. Images PMID:8658363

Cerebral infarction in association with Ecstasy abuse.

PubMed Central

Manchanda, S.; Connolly, M. J.

1993-01-01

A previously fit 35 year old man presented with a right hemiparesis and dysphasia 36 hours after abuse of Ecstasy (3,4-methylenedioxymethamphetamine). Computerized axial tomography scan demonstrated an extensive acute left cerebral infarction and carotid digital subtraction angiogram, 2 days after admission, revealed left middle cerebral artery occlusion. There were no other known risk factors and all other investigations were negative. The patient made a partial recovery. We propose an association between Ecstasy abuse and cerebral infarction. PMID:7904748

Cerebral infarction in association with Ecstasy abuse.

PubMed

Manchanda, S; Connolly, M J

1993-11-01

A previously fit 35 year old man presented with a right hemiparesis and dysphasia 36 hours after abuse of Ecstasy (3,4-methylenedioxymethamphetamine). Computerized axial tomography scan demonstrated an extensive acute left cerebral infarction and carotid digital subtraction angiogram, 2 days after admission, revealed left middle cerebral artery occlusion. There were no other known risk factors and all other investigations were negative. The patient made a partial recovery. We propose an association between Ecstasy abuse and cerebral infarction.

Uniform enhancement of optical micro-angiography images using Rayleigh contrast-limited adaptive histogram equalization

PubMed Central

Yousefi, Siavash; Qin, Jia; Zhi, Zhongwei

2013-01-01

Optical microangiography is an imaging technology that is capable of providing detailed functional blood flow maps within microcirculatory tissue beds in vivo. Some practical issues however exist when displaying and quantifying the microcirculation that perfuses the scanned tissue volume. These issues include: (I) Probing light is subject to specular reflection when it shines onto sample. The unevenness of the tissue surface makes the light energy entering the tissue not uniform over the entire scanned tissue volume. (II) The biological tissue is heterogeneous in nature, meaning the scattering and absorption properties of tissue would attenuate the probe beam. These physical limitations can result in local contrast degradation and non-uniform micro-angiogram images. In this paper, we propose a post-processing method that uses Rayleigh contrast-limited adaptive histogram equalization to increase the contrast and improve the overall appearance and uniformity of optical micro-angiograms without saturating the vessel intensity and changing the physical meaning of the micro-angiograms. The qualitative and quantitative performance of the proposed method is compared with those of common histogram equalization and contrast enhancement methods. We demonstrate that the proposed method outperforms other existing approaches. The proposed method is not limited to optical microangiography and can be used in other image modalities such as photo-acoustic tomography and scanning laser confocal microscopy. PMID:23482880

Extensive Mobile Thrombus of the Internal Carotid Discovered After Intravenous Thrombolysis

PubMed Central

Fugate, Jennifer E.; Hocker, Sara E.

2016-01-01

This case report describes a rare presentation of ischemic stroke secondary to an extensive internal carotid artery thrombus, subsequent therapeutic dilemma, and clinical management. A 58-year-old man was administered intravenous (IV) thrombolysis for right middle cerebral artery territory ischemic stroke symptoms. A computed tomography angiogram of the head and neck following thrombolysis showed a longitudinally extensive internal carotid artery thrombus originating at the region of high-grade calcific stenosis. Mechanical embolectomy was deferred because of risk of clot dislodgement and mild neurological symptoms. Recumbency and hemodynamic augmentation were used acutely to support cerebral perfusion. Anticoagulation was started 24 hours after thrombolysis. Carotid endarterectomy was completed successfully within 1 week of presentation. Clinical outcome was satisfactory with discharge modified Rankin Scale score 0. A longitudinally extensive carotid artery thrombus poses a risk of dislodgement and hemispheric stroke. Optimal management in these cases is not known with certainty. In our case, IV thrombolysis, hemodynamic augmentation, delayed anticoagulation, and carotid endarterectomy resulted in a favorable clinical outcome. PMID:28400904

Traumatic thrombosis of internal carotid artery sustained by transfer of kinetic energy.

PubMed

Kalcioglu, Mahmut Tayyar; Celbis, Osman; Mizrak, Bulent; Firat, Yezdan; Selimoglu, Erol

2012-06-01

A 31-year-old male patient with a fatal thrombosis of the internal carotid artery caused by gun shot injury was presented in this case report. The patient was referred to the hospital with a diffuse edema on his left cheek. On otolaryngologic examination, there was a bullet entrance hole at the left mandibular corpus. No exit hole could be found. The finding from his axial computed tomography of neck and paranasal sinuses was normal. On neurological examination, a dense right hemiparesis was observed. In his cerebral angiogram, left common carotid artery was totally obliterated. Diffuse ischemia was observed in the left cerebral hemisphere. Despite intensive interventions, the patient died 4 days after the accident. In the autopsy, a large thrombosis was obtained in the left common carotid artery. This case emphasizes a fatal kinetic energy effect in vascular structures. It is stressed that a gun shot injury could be fatal with its indirect kinetic energy effects at subacute phase.

Verapamil-induced breakdown of the blood-brain barrier presenting as a transient right middle cerebral artery syndrome.

PubMed

Pace, Jonathan; Nelson, Jeffrey; Ray, Abhishek; Hu, Yin

2017-12-01

A middle-aged patient presented for elective embolization of an incidentally found right internal carotid aneurysm. An angiogram was performed, during which the left internal carotid artery was visualized to evaluate a second, small aneurysm. During the embolization of the right internal carotid artery aneurysm, a catheter-induced vasospasm was identified that prompted treatment with intra-arterial verapamil. The procedure was uncomplicated; a postoperative rotational flat-panel computed tomography scan was performed on the angiography table that demonstrated right hemisphere contrast staining. The patient developed a right middle cerebral artery (MCA) syndrome after extubation with repeat cerebral angiography negative for occlusion and magnetic resonance imaging negative for stroke. The patient was observed for 48 hours, during which time the patient had slowly improved. At a six-week follow up visit, the patient had fully recovered. We present an interesting case of a verapamil-induced breakdown of the blood-brain barrier and self-limited right MCA syndrome.

Tibioperoneal Trunk Aneurysm Resulting in Compartment Syndrome with Associated Aneurysms of the Popliteal and Dorsalis Pedis Arteries.

PubMed

Ventarola, Daniel J; Labropoulos, Nicos N; Landau, David S; Tassiopoulos, Apostolos K; Loh, Shang A

2016-08-01

True aneurysms of the tibioperoneal trunk are rare. Given the scarcity of reports, the clinical presentation and treatment is not well defined. This is a case report of a 50-year-old male patient presenting with severe lower extremity swelling and compartment syndrome with neurological compromise secondary to a tibioperoneal trunk aneurysm. He was also noted to have discrete ipsilateral popliteal and dorsalis pedis artery aneurysms. Given the location and size of the aneurysm, the severe leg swelling, and venous hypertension, aneurysmorrhaphy or aneurysm sac excision with arterial reconstruction was prohibitively dangerous. Thus, following fasciotomies, a hybrid repair utilizing a saphenous vein superficial femoral to anterior tibial artery bypass along with coil embolization of the aneurysm sac was performed. The patient recovered full function of his leg and follow-up computed tomography angiogram demonstrated thrombosis and regression of the aneurysm sac with a patent bypass. Copyright © 2016 Elsevier Inc. All rights reserved.

Computational Fluid Dynamics Simulations of Hemodynamics in Plaque Erosion

PubMed Central

Campbell, Ian C.; Timmins, Lucas H.; Giddens, Don P.; Virmani, Renu; Veneziani, Alessandro; Rab, S. Tanveer; Samady, Habib; McDaniel, Michael C.; Finn, Aloke V.; Taylor, W. Robert; Oshinski, John N.

2013-01-01

Purpose We investigated whether local hemodynamics were associated with sites of plaque erosion and hypothesized that patients with plaque erosion have locally elevated WSS magnitude in regions where erosion has occurred. Methods We generated 3D, patient-specific models of coronary arteries from biplane angiographic images in 3 human patients with plaque erosion diagnosed by optical coherence tomography (OCT). Using computational fluid dynamics, we simulated pulsatile blood flow and calculated both wall shear stress (WSS) and oscillatory shear index (OSI). We also investigated anatomic features of plaque erosion sites by examining branching and local curvature in x-ray angiograms of barium-perfused autopsy hearts. Results Neither high nor low magnitudes of mean WSS were associated with sites of plaque erosion. OSI and local curvature were also not associated with erosion. Anatomically, 8 of 13 hearts had a nearby bifurcation upstream of the site of plaque erosion. Conclusions This study provides preliminary evidence that neither hemodynamics nor anatomy are predictors of plaque erosion, based upon a very unique dataset. Our sample sizes are small, but this dataset suggests that high magnitudes of wall shear stress, one potential mechanism for inducing plaque erosion, are not necessary for erosion to occur. PMID:24223678

End Tidal Carbon Dioxide as a Screening Tool for Computed Tomography Angiogram in Postoperative Orthopaedic Patients Suspected of Pulmonary Embolism.

PubMed

Ramme, Austin J; Iturrate, Eduardo; Dweck, Ezra; Steiger, David J; Hutzler, Lorraine H; Fang, Yixin; Wang, Binhuan; Bosco, Joseph A; Sigmund, Alana E

2016-10-01

Computed tomography pulmonary angiography (CTA) is the gold standard for diagnosing pulmonary embolism (PE) but involves radiation and iodinated contrast exposure. Of orthopedic patients evaluated for PE, a minority have a positive CTA study. Herein, we evaluate end tidal carbon dioxide (ETCO2) as a method to identify patients at low risk for PE and may not require a CTA. We hypothesize that ETCO2 will be useful for predicting the absence of PE in postoperative orthopedic patients. In this prospective study, all patients older than 18 years who were admitted for orthopedic surgery and who had a CTA performed for PE were eligible. These patients underwent an ETCO2 measurement. Patients were determined to have PE if they had a positive PE-protocol CT. Between May 2014 and April 2015, 121 patients met the inclusion criteria for the study. Of these patients, 84 had a negative CTA examination, 25 had a positive examination, and 12 had a nondiagnostic examination. We found a statistically significant difference (P = .03) when comparing the average ETCO2 values for the positive and negative CTA groups. An ETCO2 cutoff value of 43 mm Hg was 100% sensitive with a negative predictive value of 100% for absence of PE on CTA. This study demonstrates a significant difference in ETCO2 measurements between postoperative orthopedic patients with and without CTA-detected PE. A cutoff value of >43 mm Hg may be useful in excluding patients from undergoing CTA. Copyright © 2016 Elsevier Inc. All rights reserved.

The use of computed tomography for the estimation of DIEP flap weights in breast reconstruction: a simple mathematical formula.

PubMed

Nanidis, Theodore G; Ridha, Hyder; Jallali, Navid

2014-10-01

Estimation of the volume of abdominal tissue is desirable when planning autologous abdominal based breast reconstruction. However, this can be difficult clinically. The aim of this study was to develop a simple, yet reliable method of calculating the deep inferior epigastric artery perforator flap weight using the routine preoperative computed tomography angiogram (CTA) scan. Our mathematical formula is based on the shape of a DIEP flap resembling that of an isosceles triangular prism. Thus its volume can be calculated with a standard mathematical formula. Using bony landmarks three measurements were acquired from the CTA scan to calculate the flap weight. This was then compared to the actual flap weight harvested in both a retrospective feasibility and prospective study. In the retrospective group 17 DIEP flaps in 17 patients were analyzed. Average predicted flap weight was 667 g (range 293-1254). The average actual flap weight was 657 g (range 300-1290) giving an average percentage error of 6.8% (p-value for weight difference 0.53). In the prospective group 15 DIEP flaps in 15 patients were analyzed. Average predicted flap weight was 618 g (range 320-925). The average actual flap weight was 624 g (range 356-970) giving an average percentage error of 6.38% (p-value for weight difference 0.57). This formula is a quick, reliable and accurate way of estimating the volume of abdominal tissue using the preoperative CTA scan. Copyright © 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Coronary artery segmentation in X-ray angiograms using gabor filters and differential evolution.

PubMed

Cervantes-Sanchez, Fernando; Cruz-Aceves, Ivan; Hernandez-Aguirre, Arturo; Solorio-Meza, Sergio; Cordova-Fraga, Teodoro; Aviña-Cervantes, Juan Gabriel

2018-08-01

Segmentation of coronary arteries in X-ray angiograms represents an essential task for computer-aided diagnosis, since it can help cardiologists in diagnosing and monitoring vascular abnormalities. Due to the main disadvantages of the X-ray angiograms are the nonuniform illumination, and the weak contrast between blood vessels and image background, different vessel enhancement methods have been introduced. In this paper, a novel method for blood vessel enhancement based on Gabor filters tuned using the optimization strategy of Differential evolution (DE) is proposed. Because the Gabor filters are governed by three different parameters, the optimal selection of those parameters is highly desirable in order to maximize the vessel detection rate while reducing the computational cost of the training stage. To obtain the optimal set of parameters for the Gabor filters, the area (Az) under the receiver operating characteristics curve is used as objective function. In the experimental results, the proposed method achieves an A z =0.9388 in a training set of 40 images, and for a test set of 40 images it obtains the highest performance with an A z =0.9538 compared with six state-of-the-art vessel detection methods. Finally, the proposed method achieves an accuracy of 0.9423 for vessel segmentation using the test set. In addition, the experimental results have also shown that the proposed method can be highly suitable for clinical decision support in terms of computational time and vessel segmentation performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optical coherence tomography angiography in age-related macular degeneration: The game changer.

PubMed

Lupidi, Marco; Cerquaglia, Alessio; Chhablani, Jay; Fiore, Tito; Singh, Sumit Randhir; Cardillo Piccolino, Felice; Corbucci, Roberta; Coscas, Florence; Coscas, Gabriel; Cagini, Carlo

2018-04-01

Optical coherence tomography angiography is one of the biggest advances in ophthalmic imaging. It enables a depth-resolved assessment of the retinal and choroidal blood flow, far exceeding the levels of detail commonly obtained with dye angiographies. One of the first applications of optical coherence tomography angiography was in detecting the presence of choroidal neovascularization in age-related macular degeneration and establishing its position in relation to the retinal pigmented epithelium and Bruch's membrane, and thereby classifying the CNV as type 1, type 2, type 3, or mixed lesions. Optical coherence tomography angiograms, due to the longer wavelength used by optical coherence tomography, showed a more distinct choroidal neovascularization vascular pattern than fluorescein angiography, since there is less suffering from light scattering or is less obscured by overlying subretinal hemorrhages or exudation. Qualitative and quantitative assessments of optical coherence tomography angiography findings in exudative and nonexudative age-related macular degeneration have been largely investigated within the past 3 years both in clinical and experimental settings. This review constitutes an up-to-date of all the potential applications of optical coherence tomography angiography in age-related macular degeneration in order to better understand how to translate its theoretical usefulness into the current clinical practice.

Automated myocardial perfusion from coronary x-ray angiography

NASA Astrophysics Data System (ADS)

Storm, Corstiaan J.; Slump, Cornelis H.

2010-03-01

The purpose of our study is the evaluation of an algorithm to determine the physiological relevance of a coronary lesion as seen in a coronary angiogram. The aim is to extract as much as possible information from a standard coronary angiogram to decide if an abnormality, percentage of stenosis, as seen in the angiogram, results in physiological impairment of the blood supply of the region nourished by the coronary artery. Coronary angiography, still the golden standard, is used to determine the cause of angina pectoris based on the demonstration of an important stenose in a coronary artery. Dimensions of a lesion such as length and percentage of narrowing can at present easily be calculated by using an automatic computer algorithm such as Quantitative Coronary Angiography (QCA) techniques resulting in just anatomical information ignoring the physiological relevance of the lesion. In our study we analyze myocardial perfusion images in standard coronary angiograms in rest and in artificial hyperemic phases, using a drug e.g. papaverine intracoronary. Setting a Region of Interest (ROI) in the angiogram without overlying major vessels makes it possible to calculate contrast differences as a function of time, so called time-density curves, in the basal and hyperemic phases. In minimizing motion artifacts, end diastolic images are selected ECG based in basal and hyperemic phase in an identical ROI in the same angiographic projection. The development of new algorithms for calculating differences in blood supply in the region as set are presented together with the results of a small clinical case study using the standard angiographic procedure.

Imaging Features of the Brain, Cerebral Vessels and Spine in Pediatric Tuberculous Meningitis with Associated Hydrocephalus

PubMed Central

Rohlwink, Ursula K; Kilborn, Tracy; Wieselthaler, Nicky; Banderker, Ebrahim; Zwane, Eugene; Figaji, Anthony A.

2016-01-01

Background Pediatric tuberculous meningitis leads to high rates of mortality and morbidity. Prompt diagnosis and initiation of treatment are challenging; imaging findings play a key role in establishing the presumptive diagnosis. General brain imaging findings are well reported; however, specific data on cerebral vascular and spinal involvement in children are sparse. Methods This prospective cohort study examined admission and follow up computed tomography brain scans and magnetic resonance imaging scans of the brain, cerebral vessels (magnetic resonance angiogram) and spine at 3 weeks in children treated for tuberculous meningitis with hydrocephalus (inclusion criteria). Exclusion criteria were no hydrocephalus on admission, treatment of hydrocephalus or commencement of anti-TB treatment before study enrolment. Imaging findings were examined in association with outcome at 6 months. Results Forty-four patients (median age 3.3 [0.3-13.1] years) with definite (54%) or probable tuberculous meningitis were enrolled. Good clinical outcome was reported in 72%; the mortality rate was 16%. Infarcts were reported in 66% of patients and were predictive of poor outcome. Magnetic resonance angiogram abnormalities were reported in 55% of patients. Delayed tuberculomas developed in 11% of patients (after starting treatment). Spinal pathology was more common than expected, occurring in 76% of patients. Exudate in the spinal canal increased the difficulty of lumbar puncture and correlated with high cerebrospinal fluid protein content. Conclusion Tuberculous meningitis involves extensive pathology in the central nervous system. Severe infarction was predictive of poor outcome although this was not the case for angiographic abnormalities. Spinal disease occurs commonly and has important implications for diagnosis and treatment. Comprehensive imaging of the brain, spine and cerebral vessels adds insight into disease pathophysiology. PMID:27213261

Amplatzer Vascular Plugs Versus Coils for Embolization of Pulmonary Arteriovenous Malformations in Patients with Hereditary Hemorrhagic Telangiectasia.

PubMed

Tau, Noam; Atar, Eliyahu; Mei-Zahav, Meir; Bachar, Gil N; Dagan, Tamir; Birk, Einat; Bruckheimer, Elchanan

2016-08-01

Coil embolization of pulmonary arteriovenous malformations (PAVMs) has a high re-canalization/re-perfusion rate. Embolization with Amplatzer plugs has been previously described, but the long-term efficacy is not established. This study reports the experience of a referral medical center with the use of coils and Amplatzer plugs for treating PAVMs in patients with hereditary hemorrhagic telangiectasia. The study was approved by the Institutional Review Board with waiver of informed consent. The cohort included all patients who underwent PAVM embolization in 2004-2014 for whom follow-up imaging scans were available. The medical files were retrospectively reviewed for background data, embolization method (coils, Amplatzer plugs, both), and complications. Re-canalization of treated PAVMs was assessed from intrapulmonary angiograms (following percutaneous procedures) or computed tomography angiograms. Fisher's exact test and Pearson Chi-squared test or t test were used for statistical analysis, with significance at p < 0.05. 16 patients met the study criteria. Imaging scans were available for 63 of the total 110 PAVMs treated in 41 procedures. Coils were used for embolization in 37 PAVMs, Amplatzer plugs in 21, and both in five. Median follow-up time was 7.7 years (range 1.4-18.9). Re-canalization was detected in seven vessels, all treated with coils; there were no cases of re-canalization in plug-occluded vessels (p = 0.0413). The use of Amplatzer plugs for the embolization of PAVMs in patients with hemorrhagic telangiectasia is associated with a significantly lower rate of re-canalization of feeding vessels than coils. Long-term prospective studies are required to confirm these findings.

Imaging Features of the Brain, Cerebral Vessels and Spine in Pediatric Tuberculous Meningitis With Associated Hydrocephalus.

PubMed

Rohlwink, Ursula K; Kilborn, Tracy; Wieselthaler, Nicky; Banderker, Ebrahim; Zwane, Eugene; Figaji, Anthony A

2016-10-01

Pediatric tuberculous meningitis (TBM) leads to high rates of mortality and morbidity. Prompt diagnosis and initiation of treatment are challenging; imaging findings play a key role in establishing the presumptive diagnosis. General brain imaging findings are well reported; however, specific data on cerebral vascular and spinal involvement in children are sparse. This prospective cohort study examined admission and followed up computed tomography brain scans and magnetic resonance imaging scans of the brain, cerebral vessels (magnetic resonance angiogram) and spine at 3 weeks in children treated for TBM with hydrocephalus (HCP; inclusion criteria). Exclusion criteria were no HCP on admission, treatment of HCP or commencement of antituberculosis treatment before study enrollment. Imaging findings were examined in association with outcome at 6 months. Forty-four patients (median age 3.3 [0.3-13.1] years) with definite (54%) or probable TBM were enrolled. Good clinical outcome was reported in 72%; the mortality rate was 16%. Infarcts were reported in 66% of patients and were predictive of poor outcome. Magnetic resonance angiogram abnormalities were reported in 55% of patients. Delayed tuberculomas developed in 11% of patients (after starting treatment). Spinal pathology was more common than expected, occurring in 76% of patients. Exudate in the spinal canal increased the difficulty of lumbar puncture and correlated with high cerebrospinal fluid protein content. TBM involves extensive pathology in the central nervous system. Severe infarction was predictive of poor outcome although this was not the case for angiographic abnormalities. Spinal disease occurs commonly and has important implications for diagnosis and treatment. Comprehensive imaging of the brain, spine and cerebral vessels adds insight into disease pathophysiology.

Amplatzer Vascular Plugs Versus Coils for Embolization of Pulmonary Arteriovenous Malformations in Patients with Hereditary Hemorrhagic Telangiectasia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tau, Noam, E-mail: taunoam@gmail.com; Atar, Eliyahu; Mei-Zahav, Meir

PurposeCoil embolization of pulmonary arteriovenous malformations (PAVMs) has a high re-canalization/re-perfusion rate. Embolization with Amplatzer plugs has been previously described, but the long-term efficacy is not established. This study reports the experience of a referral medical center with the use of coils and Amplatzer plugs for treating PAVMs in patients with hereditary hemorrhagic telangiectasia.MethodsThe study was approved by the Institutional Review Board with waiver of informed consent. The cohort included all patients who underwent PAVM embolization in 2004–2014 for whom follow-up imaging scans were available. The medical files were retrospectively reviewed for background data, embolization method (coils, Amplatzer plugs, both),more » and complications. Re-canalization of treated PAVMs was assessed from intrapulmonary angiograms (following percutaneous procedures) or computed tomography angiograms. Fisher’s exact test and Pearson Chi-squared test or t test were used for statistical analysis, with significance at p < 0.05.Results16 patients met the study criteria. Imaging scans were available for 63 of the total 110 PAVMs treated in 41 procedures. Coils were used for embolization in 37 PAVMs, Amplatzer plugs in 21, and both in five. Median follow-up time was 7.7 years (range 1.4–18.9). Re-canalization was detected in seven vessels, all treated with coils; there were no cases of re-canalization in plug-occluded vessels (p = 0.0413).ConclusionThe use of Amplatzer plugs for the embolization of PAVMs in patients with hemorrhagic telangiectasia is associated with a significantly lower rate of re-canalization of feeding vessels than coils. Long-term prospective studies are required to confirm these findings.« less

[Effectiveness of heart tumor therapy in the cardiology department during 7 year follow-up].

PubMed

Dabek, Józefa; Twardowski, Romuald; Jakubowski, Daniel; Michniak, Barbara; Swiderski, Robert; Gasior, Zbigniew

2009-11-01

Neoplasms of the heart are rare. Usually asymptomatic on the early stage are diagnosed incidentally. Among primary heart neoplasms the most often benign tumors are diagnosed--mostly myxomas, whereas the majority of malignant heart tumors are sarcomas. The aim of this paper was to present heart tumors diagnosed in the cardiology department, their symptoms, used diagnostic tests and therapy and to show after therapy quality of life changes. There were 18 patients included to the study, whom during hospitalization in the cardiology department heart tumors were diagnosed. There were 11 women and 7 men, aged from 33- to 76-years-old (mean 60,5 years). To all of the patients medical interview, physical examination, EKG, UCG and laboratory test were performed. Additionally in some cases computed tomography or magnetic resonance imaging of the chest and coronary angiograms were done. Based on the diagnostic tests results the patients were qualified to conservative or surgical treatment. Among 18 heart tumor patients in 12 cases primary benign tumors were diagnosed (66,6%), 1 patient had primary malignant tumor (5,5%), there were 3 cases of metastatic tumors (16,6%) and 2 patients with non-neoplasmic tumors--clots (11,1%). From 18 subjects with heart tumor 3 patients died because of advanced stage of neoplasmic disease and presence of metastatic tumors in the heart. Results of the study show, that heart tumors, regardless of development of diagnostic tests, are still diagnosed too late. The study group follow-up proved, that early diagnosis and proper heart tumor treatment prevented complications and improved the quality of life. It is worth to emphasize, that coronary angiogram in some cases allowed to diagnose coronary artery disease, to treat heart tumor and to perform coronary artery by-pass grafting simultaneously.

Segmentation of Coronary Angiograms Using Gabor Filters and Boltzmann Univariate Marginal Distribution Algorithm

PubMed Central

Cervantes-Sanchez, Fernando; Hernandez-Aguirre, Arturo; Solorio-Meza, Sergio; Ornelas-Rodriguez, Manuel; Torres-Cisneros, Miguel

2016-01-01

This paper presents a novel method for improving the training step of the single-scale Gabor filters by using the Boltzmann univariate marginal distribution algorithm (BUMDA) in X-ray angiograms. Since the single-scale Gabor filters (SSG) are governed by three parameters, the optimal selection of the SSG parameters is highly desirable in order to maximize the detection performance of coronary arteries while reducing the computational time. To obtain the best set of parameters for the SSG, the area (A z) under the receiver operating characteristic curve is used as fitness function. Moreover, to classify vessel and nonvessel pixels from the Gabor filter response, the interclass variance thresholding method has been adopted. The experimental results using the proposed method obtained the highest detection rate with A z = 0.9502 over a training set of 40 images and A z = 0.9583 with a test set of 40 images. In addition, the experimental results of vessel segmentation provided an accuracy of 0.944 with the test set of angiograms. PMID:27738422

Automated volumetric segmentation of retinal fluid on optical coherence tomography

PubMed Central

Wang, Jie; Zhang, Miao; Pechauer, Alex D.; Liu, Liang; Hwang, Thomas S.; Wilson, David J.; Li, Dengwang; Jia, Yali

2016-01-01

We propose a novel automated volumetric segmentation method to detect and quantify retinal fluid on optical coherence tomography (OCT). The fuzzy level set method was introduced for identifying the boundaries of fluid filled regions on B-scans (x and y-axes) and C-scans (z-axis). The boundaries identified from three types of scans were combined to generate a comprehensive volumetric segmentation of retinal fluid. Then, artefactual fluid regions were removed using morphological characteristics and by identifying vascular shadowing with OCT angiography obtained from the same scan. The accuracy of retinal fluid detection and quantification was evaluated on 10 eyes with diabetic macular edema. Automated segmentation had good agreement with manual segmentation qualitatively and quantitatively. The fluid map can be integrated with OCT angiogram for intuitive clinical evaluation. PMID:27446676

Computational fluid dynamics (CFD) using porous media modeling predicts recurrence after coiling of cerebral aneurysms.

PubMed

Umeda, Yasuyuki; Ishida, Fujimaro; Tsuji, Masanori; Furukawa, Kazuhiro; Shiba, Masato; Yasuda, Ryuta; Toma, Naoki; Sakaida, Hiroshi; Suzuki, Hidenori

2017-01-01

This study aimed to predict recurrence after coil embolization of unruptured cerebral aneurysms with computational fluid dynamics (CFD) using porous media modeling (porous media CFD). A total of 37 unruptured cerebral aneurysms treated with coiling were analyzed using follow-up angiograms, simulated CFD prior to coiling (control CFD), and porous media CFD. Coiled aneurysms were classified into stable or recurrence groups according to follow-up angiogram findings. Morphological parameters, coil packing density, and hemodynamic variables were evaluated for their correlations with aneurysmal recurrence. We also calculated residual flow volumes (RFVs), a novel hemodynamic parameter used to quantify the residual aneurysm volume after simulated coiling, which has a mean fluid domain > 1.0 cm/s. Follow-up angiograms showed 24 aneurysms in the stable group and 13 in the recurrence group. Mann-Whitney U test demonstrated that maximum size, dome volume, neck width, neck area, and coil packing density were significantly different between the two groups (P < 0.05). Among the hemodynamic parameters, aneurysms in the recurrence group had significantly larger inflow and outflow areas in the control CFD and larger RFVs in the porous media CFD. Multivariate logistic regression analyses demonstrated that RFV was the only independently significant factor (odds ratio, 1.06; 95% confidence interval, 1.01-1.11; P = 0.016). The study findings suggest that RFV collected under porous media modeling predicts the recurrence of coiled aneurysms.

Association of brain abscess with a mycotic aneurysm of the contralateral internal carotid artery in a patient of cyanotic heart disease

PubMed Central

Bansal, Sumit; Borkar, Sachin A.; Mahapatra, Ashok K.

2017-01-01

Congenital cyanotic heart disease can lead to intra-cranial involvement. Authors report a very rare case of right intra-cerebral abscess diagnosed on computerized tomography (CT) scan and simultaneous presence of an aneurysm of the left internal carotid artery diagnosed on CT angiogram in a 15-year-old child with congenital cyanotic heart disease with recent onset left hemiparesis. Right cerebral abscess was tapped and left internal carotid aneurysm was planned to be followed up by giving antibiotics and serial angiograms, but he could not survive and died due to non-cranial cause. We conclude that cerebral angiography is necessary to diagnose cerebro-vascular complications, including infectious aneurysms, in cases presenting with unusual findings on neuroimaging study. Patient must undergo serial angiography while being on intravenous antibiotics. Intervention (either surgical or endovascular) should be considered if there are no signs of regression of size of aneurysm or in the presence of aneurysm rupture. We have not been able to find a similar case in the English literature. PMID:28484536

Can image enhancement allow radiation dose to be reduced whilst maintaining the perceived diagnostic image quality required for coronary angiography?

PubMed Central

Joshi, Anuja; Gislason-Lee, Amber J; Keeble, Claire; Sivananthan, Uduvil M

2017-01-01

Objective: The aim of this research was to quantify the reduction in radiation dose facilitated by image processing alone for percutaneous coronary intervention (PCI) patient angiograms, without reducing the perceived image quality required to confidently make a diagnosis. Methods: Incremental amounts of image noise were added to five PCI angiograms, simulating the angiogram as having been acquired at corresponding lower dose levels (10–89% dose reduction). 16 observers with relevant experience scored the image quality of these angiograms in 3 states—with no image processing and with 2 different modern image processing algorithms applied. These algorithms are used on state-of-the-art and previous generation cardiac interventional X-ray systems. Ordinal regression allowing for random effects and the delta method were used to quantify the dose reduction possible by the processing algorithms, for equivalent image quality scores. Results: Observers rated the quality of the images processed with the state-of-the-art and previous generation image processing with a 24.9% and 15.6% dose reduction, respectively, as equivalent in quality to the unenhanced images. The dose reduction facilitated by the state-of-the-art image processing relative to previous generation processing was 10.3%. Conclusion: Results demonstrate that statistically significant dose reduction can be facilitated with no loss in perceived image quality using modern image enhancement; the most recent processing algorithm was more effective in preserving image quality at lower doses. Advances in knowledge: Image enhancement was shown to maintain perceived image quality in coronary angiography at a reduced level of radiation dose using computer software to produce synthetic images from real angiograms simulating a reduction in dose. PMID:28124572

Retrosternal abscess after trigger point injections in a pregnant woman: a case report.

PubMed

Usman, Faisal; Bajwa, Abubakr; Shujaat, Adil; Cury, James

2011-08-23

Although retrosternal abscess is a well known complication of sternotomy and intravenous drug abuse, to date it has not been described as a consequence of trigger point injections. There are reported cases of serious complications as a result of this procedure including epidural abscess, necrotizing fasciitis, osteomyelitis and gas gangrene. A 37-year-old African-American woman, who was 20 weeks pregnant, presented to our emergency room with complaints of progressively worsening chest pain and shortness of breath over the course of the last two months. She was undergoing trigger point injections at multiple different sites including the sternoclavicular joint for chest pain and dystonia. Two years previously she had developed a left-sided pneumothorax as a result of this procedure, requiring chest tube placement and subsequent pleurodesis. Her vital signs in our emergency room were normal except for resting tachycardia, with a pulse of 100 beats per minute. A physical examination revealed swelling and tenderness of the sternal notch with tenderness to palpation over the left sternoclavicular joint. Laboratory data was significant for a white blood count of 13.3 × 109/L with 82% granulocytes. A chest radiograph revealed left basilar scarring with blunting of the left costophrenic angle. A computed tomography angiogram showed a 4.7 cm abscess in the retrosternal region behind the manubrium with associated sclerosis and cortical irregularity of the manubrium and left clavicle. Trigger point injection is generally considered very safe. However, there are reported cases of serious complications as a result of this procedure. A computed tomography scan of the chest should strongly be considered in the evaluation of chest pain and shortness of breath of unclear etiology in patients with even a remote history of trigger point injections.

Using Multidetector Computed Tomography in a Swine Model to Assess the Effects of Sublingual Nitroglycerin and Intravenous Adenosine on Epicardial Coronary Arteries

PubMed Central

Clarkson, Wesley A; Restrepo, Carlos Santiago; Bauch, Terry D; Rubal, Bernard J

2009-01-01

This study examines the effects of intravenous infusion of adenosine and sublingual nitroglycerin on coronary angiograms obtained by current-generation multidetector computed tomography. We assessed coronary vasodilation at baseline and after intravenous adenosine (140 µg/kg/min) or sublingual nitroglycerin spray (800 µg) in 7 female swine (weight, 40.9 ± 1.4 kg) by using electrocardiogram-gated coronary angiography with a 64-detector scanner (rotation time, 400 ms; 120kV; 400 mA) and intravenous contrast (300 mg/mL iohexol, 4.5 mL/s, 2 mL/kg). Cross-sectional areas of segments in the left anterior descending, circumflex, and right coronary arteries were evaluated in oblique orthogonal views. Images were acquired at an average heart rate of 73 ± 11 beats per minute. Changes in aortic pressure were not significant with nitroglycerin but decreased (approximately 10%) with adenosine. Of the 76 segments analyzed (baseline range, 2 to 39 mm2), 1 distal segment could not be assessed after adenosine. Segment cross-sectional area increased by 11.3% with nitroglycerin but decreased by 9.6% during adenosine infusion. The results of the present study are consistent with the practice of using sublingual nitroglycerin to enhance visualization of epicardial vessels and suggest that intravenous adenosine may hinder coronary artery visualization. This study is the first repeated-measures electrocardiogram-gated CT evaluation to use the same imaging technology to assess changes in coronary cross-sectional area before and after treatment with a vasodilator. The nitroglycerin-associated changes in our swine model were modest in comparison with previously reported human studies. PMID:20034433

ECG-triggered high-pitch CT for simultaneous assessment of the aorta and coronary arteries.

PubMed

Hachulla, Anne-Lise; Ronot, Maxime; Noble, Stéphane; Becker, Christoph D; Montet, Xavier; Vallée, Jean-Paul

2016-01-01

To study the image quality of ECG-gated-computed tomography (CT) acquisition with a high-pitch CT imaging for the exploration of both the aorta and coronary arteries. Eighty-four patients underwent high-pitch ECG-gated aortic CT without β-blockers with iterative reconstruction algorithms. Contrast-to-noise ratio (CNR) between vessels and adjacent perivascular fat tissue were calculated on the aorta and the coronary arteries. Dose-length-products (DLP) were recorded. Two blinded readers graded image quality of the aorta and the coronary arteries on a 3-point scale. Coronary artery stenoses were compared with coronary angiograms in 24 patients. Kappa values were calculated. High-pitch acquisition resulted in a mean DLP of 234 ± 93 mGy cm(4.2 mSv) for an acquisition of the entire aorta, (mean 73 ± 16 bpm). CNR for ascending aorta was 10.6 ± 4 and CNR for coronary arteries was 9.85 ± 4.1. Image quality was excellent in 79/84 patients (94%), and excellent or moderate but diagnostic in 1087/1127 coronary artery segments (96%). 74 significant stenoses were observed, and 38/40 significant stenoses were confirmed by coronary angiography (K = 0.91, Sensitivity = 0.97, Specificity = 0.98). High-pitch ECG-gated aortic CT with iterative reconstructions allows an accurate exploration of both aorta and coronary arteries during the same acquisition, with limited dose deposition, despite the lack of β-blockers and relatively high heart rate. Radiologists need to be aware of the necessity to analyze and report coronary artery disease in aortic examination. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

Comparison of intra-aortic computed tomography angiography to conventional angiography in the presurgical visualization of the Adamkiewicz artery: first results in patients with thoracoabdominal aortic aneurysms.

PubMed

Clarençon, Frédéric; Di Maria, Federico; Cormier, Evelyne; Gaudric, Julien; Sourour, Nader; Gabrieli, Joseph; Iosif, Christina; Jenny, Catherine; Koskas, Fabien; Chiras, Jacques

2013-11-01

The aim of this study was to compare the sensitivity of intra-aortic computed tomography angiography (IA-CTA) to that of regular spinal digital subtraction angiography for the presurgical location of the Adamkiewicz artery (AKA). Thirty patients (21 males, 9 females; mean age 64 years) had an IA-CTA for the location of the AKA before surgery of aneurysm (n = 24) or dissection (n = 6) of the thoracoabdominal aorta. After femoral artery puncture, a pigtail catheter was positioned at the origin of the descending aorta. CT acquisition was performed with an intra-aortic iodinated contrast media injection (15 mL/s, 120 mL). The visualization of the AKA and the location of the feeder(s) to the AKA were independently evaluated by two observers. Interrater agreement was calculated using a kappa test. Spinal angiogram by selective catheterization was systematically performed to confirm the results of the IA-CTA. The AKA was visualized by the IA-CTA in 27/30 cases (90 %); in 26/31 (84 %) cases, the continuity with the aorta was satisfactorily seen. Interrater agreement was good for the visualization of the AKA and its feeder(s): 0.625 and 0.87, respectively. In 75 % of the cases for which the AKA was visualized, the selective catheterization confirmed the results of the IA-CTA. In the remaining 25 % of the cases, the selective catheterization could not be performed due to marked vessels' tortuosity or ostium stenosis. IA-CTA is a feasible technique in a daily practice that presents a good sensitivity for the location of the AKA.

Completion of the Circle of Willis Varies by Gender, Age, and Indication for Computed Tomography Angiography.

PubMed

Zaninovich, Orel A; Ramey, Wyatt L; Walter, Christina M; Dumont, Travis M

2017-10-01

The circle of Willis (CoW) is the foremost anastomosis and blood distribution center of the brain. Its effectiveness depends on its completion and the size and patency of its vessels. Gender-related and age-related anatomic variations in the CoW may play an important role in the pathogenesis of cerebrovascular diseases. In this study, we analyzed computed tomography angiograms (CTAs) to assess for differences in CoW completion related to gender, age, and indication for CTA. A total of 834 CTAs were retrospectively analyzed for all CoW vessels to compare the incidence of complete CoW and variation frequency based on gender, age, and indication. The incidence of complete CoW was 37.1% overall. CoW completion showed a statistically significant decrease with increasing age for all age groups in both men (47.0%, 29.4%, 18.8%) and women (59.1%, 44.2%, 30.9%). Completion was greater in women (43.8%) than in men (31.2%) overall and for all age groups. These gender differences were all statistically significant except for the 18-39 years age group. The most frequent of the 28 CoW variations were absent posterior communicating artery (PCOM) bilaterally (17.1%), right PCOM (15.3%), and left PCOM (10.9%). Ischemic stroke and the 18-39 years age group of hemorrhagic stroke showed a statistically significant reduction in completion relative to trauma. The incidence of complete CoW is likely greater in women for all age groups and likely decreases with age in both genders. The most frequently absent vessel is likely the PCOM, either unilaterally or bilaterally. Completion may play a role in ischemic stroke and a subset of patients with hemorrhagic stroke. Copyright © 2017 Elsevier Inc. All rights reserved.

Cerebellar hematoma in a patient with Marfan syndrome.

PubMed

Passalacqua, Marcello; Grasso, Giovanni; Alafaci, Concetta; Collufio, Domenicantonio; Morabito, Antonio; Salpietro, Francesco M; Tomasello, Francesco

2003-08-01

Marfan syndrome is a connective tissue disorder affecting many structures, including the skeleton, lungs, eyes, heart and blood vessels. It is an autosomal dominant inherited disorder due to a mutation of a gene encoding fibrillin-1, which affects connective tissue. Few case reports have associated Marfan syndrome with vascular malformations of the brain and spinal cord. In this regard, association with intracranial aneurysm has been vaguely proposed. We report here a patient with Marfan syndrome who was admitted because of a sudden loss of consciousness. The patient underwent computed tomography (CT) examination, which disclosed a right intracerebellar hematoma. Cerebral angiogram did not demonstrate aneurysm or arteriovenous malformation (AVM), or evidence of any other vascular lesions or neoplasms in the posterior fossa. Conservative treatment was undertaken. The clinical course was uneventful and after 6 weeks the patient was discharged free of symptoms. Although patients with Marfan syndrome are at high risk of vascular abnormalities, a clear association with cerebral aneurysm has not yet been established. Our experience and the contrasting reports available in the medical literature strongly warrant further studies in order to better clarify this controversial association.

Dural cavernous sinus fistula: an unusual presentation.

PubMed Central

Procope, J. A.; Kidwell, E. D.; Copeland, R. A.; Perry, A. F.

1994-01-01

This article describes a 22-year-old man who presented to the Howard University Hospital emergency room with acute onset of swelling, proptosis, and decreased vision in the right eye preceded by 24 hours of nausea and vomiting. The patient's visual acuity was count fingers in the involved eye with marked proptosis and limitation of ocular motility. There was no history given of any ocular or head trauma. A computed tomography scan of the orbits showed diffuse symmetric enlargement of the extraocular muscles of the right eye, felt to be consistent with an orbital inflammatory pseudotumor. The patient was treated with intravenous steroids initially, then placed on oral prednisone. After minimal improvement on the steroids, a selective external carotid angiogram showed a moderate-sized dural cavernous sinus fistula. The patient underwent selective embolization of the fistula with rapid resolution of periorbital edema and proptosis. Visual acuity was stabilized at 20/200 in the right eye. The differential diagnosis and pathogenesis of carotid cavernous sinus fistulas and the likely pathogenesis of the fistula in this case are discussed. Images Figure 1 Figure 2 Figure 3 PMID:8046763

Vascular ring presenting as dysphagia in an adult woman: a case report.

PubMed

Powell, B L

2017-01-01

A 48-year-old woman was seen in a surgical outpatient clinic with a 2 year history of progressive dysphagia with occasional regurgitation, partially controlled with a proton pump inhibitor. Primary investigations of pH testing and gastroscopy were normal, although a barium swallow study revealed significant hold-up at the aortic arch impression and a posterior right-sided oesophageal impression suggestive of a right-sided aortic arch. A follow-up computed tomography angiogram discovered a vascular ring encircling the trachea and oesophagus, formed by a right-sided aortic arch with aberrant aortic branches, and a Kommerell's diverticulum. It was deemed that the patient's symptoms were related to this vascular ring. The patient underwent stage-one surgery - an extra-anatomic bypass of the double aortic arch and right subclavian artery - and 4 months later a stent graft insertion over the origin of the diverticulum with the aim of complete symptomatic relief. This case presents a common symptom familiar to any clinician (dysphagia), which has been caused by a rare pathology. It is even more unusual that this should present itself in adulthood.

Pitfalls in 16-detector row CT of the coronary arteries.

PubMed

Nakanishi, Tadashi; Kayashima, Yasuyo; Inoue, Rintaro; Sumii, Kotaro; Gomyo, Yukihiko

2005-01-01

Recently developed 16-detector row computed tomography (CT) has been introduced as a reliable noninvasive imaging modality for evaluating the coronary arteries. In most cases, with appropriate premedication that includes beta-blockers and nitroglycerin, ideal data sets can be acquired from which to obtain excellent-quality coronary CT angiograms, most often with multiplanar reformation, thin-slab maximum intensity projection, and volume rendering. However, various artifacts associated with data creation and reformation, postprocessing methods, and image interpretation can hamper accurate diagnosis. These artifacts can be related to pulsation (nonassessable segments, pseudostenosis) as well as rhythm disorders, respiratory issues, partial volume averaging effect, high-attenuation entities, inappropriate scan pitch, contrast material enhancement, and patient body habitus. Some artifacts have already been resolved with technical advances, whereas others represent partially inherent limitations of coronary CT angiography. Familiarity with the pitfalls of coronary angiography with 16-detector row CT, coupled with the knowledge of both the normal anatomy and anatomic variants of the coronary arteries, can almost always help radiologists avoid interpretive errors in the diagnosis of coronary artery stenosis. (c) RSNA, 2005.

Vascular complications following prophylactic balloon occlusion of the internal iliac arteries resolved by successful interventional thrombolysis in a patient with morbidly adherent placenta*

PubMed Central

Zhang, Ning; Lou, Wei-hua; Zhang, Xue-bin; Fu, Jia-ning; Chen, Yun-yan; Zhuang, Zhi-guo; Lin, Jian-hua

2017-01-01

The increasing incidence of morbidly adherent placenta (MAP) is placing women at a higher risk of life-threatening massive hemorrhage. The involvement of interventional radiology to manage this complex condition by performing prophylactic iliac artery balloon occlusion has been reported recently. However, the effectiveness and safety of this technique have not been fully determined. Here we report the case of a 25-year-old woman with placenta increta with preemptive bilateral internal iliac artery balloons who had external iliac artery thrombosis detected by computed tomography angiography (CTA) 72 h post cesarean section. A digital subtraction angiogram (DSA) and intra-arterial thrombolysis were instantly performed followed by supplementary conservative treatments, leading to a desirable resolution of thrombus without sequela. This is the first report of vascular complications with successful interventional thrombolysis in this setting. Our experience suggests that prophylactic iliac artery balloon occlusion should be used cautiously in cases of MAP and consideration given to minimizing vascular complications given the hypercoagulable state of pregnancy. PMID:28271663

Visualization of tumor vascular reactivity in response to respiratory challenges by optical coherence tomography (Conference Presentation)

NASA Astrophysics Data System (ADS)

Kim, Hoon Sup; Lee, Songhyun; Lee, Kiri; Eom, Tae Joong; Kim, Jae G.

2016-02-01

We previously reported the potential of using vascular reactivity during respiratory challenges as a marker to predict the response of breast tumor to chemotherapy in a rat model by using a continuous wave near-infrared spectroscopy. However, it cannot visualize how the vascular reactivity from tumor vessel can predict the tumor response to its treatment. In this study, we utilized a spectral domain optical coherence tomography (SD-OCT) system to visualize vascular reactivity of both tumor and normal vasculature during respiratory challenges in a mouse model. We adapted intensity based Doppler variance algorithm to draw angiogram from the ear of mouse (8-week-old Balb/c nu/nu). Animals were anesthetized using 1.5% isoflurane, and the body temperature was maintained by a heating pad. Inhalational gas was switched from air (10min) to 100% oxygen (10min), and a pulse oximeter was used to monitor arterial oxygen saturation and heart rate. OCT angiograms were acquired 5 min after the onset of each gas. The vasoconstriction effect of hyperoxic gas on vasculature was shown by subtracting an en-face image acquired during 100% oxygen from the image acquired during air inhalation. The quantitative change in the vessel diameter was measured from the en-face OCT images of the individual blood vessels. The percentage of blood vessel diameter reduction varied from 1% to 12% depending on arterial, capillary, or venous blood vessel. The vascular reactivity change during breast tumor progression and post chemotherapy will be monitored by OCT angiography.

Radial Peripapillary Capillary Network Visualized Using Wide-Field Montage Optical Coherence Tomography Angiography.

PubMed

Mase, Tomoko; Ishibazawa, Akihiro; Nagaoka, Taiji; Yokota, Harumasa; Yoshida, Akitoshi

2016-07-01

We quantitatively analyzed the features of a radial peripapillary capillary (RPC) network visualized using wide-field montage optical coherence tomography (OCT) angiography in healthy human eyes. Twenty eyes of 20 healthy subjects were recruited. En face 3 × 3-mm OCT angiograms of multiple locations in the posterior pole were acquired using the RTVue XR Avanti, and wide-field montage images of the RPC were created. To evaluate the RPC density, the montage images were binarized and skeletonized. The correlation between the RPC density and the retinal nerve fiber layer (RNFL) thickness measured by an OCT circle scan was investigated. The RPC at the temporal retina was detected as far as 7.6 ± 0.7 mm from the edge of the optic disc but not around the perifoveal area within 0.9 ± 0.1 mm of the fovea. Capillary-free zones beside the first branches of the arterioles were significantly (P < 0.0001) narrower than those beside the second ones. The RPC densities at 0.5, 2.5, and 5 mm from the optic disc edge were 13.6 ± 0.8, 11.9 ± 0.9, and 10.4 ± 0.9 mm-1. The RPC density also was correlated significantly (r = 0.64, P < 0.0001) with the RNFL thickness, with the greatest density in the inferotemporal region. Montage OCT angiograms can visualize expansion of the RPC network. The RPC is present in the superficial peripapillary retina in proportion to the RNFL thickness, supporting the idea that the RPC may be the vascular network primarily responsible for RNFL nourishment.

The Supraclavicular Artery Perforator Flap: A Comparative Study of Imaging Techniques Used in Preoperative Mapping.

PubMed

Sheriff, Hemin Oathman; Mahmood, Kawa Abdullah; Hamawandi, Nzar; Mirza, Aram Jamal; Hawas, Jawad; Moreno, Esther Granell; Clavero, Juan Antonio; Hankins, Christopher; Masia, Jaume

2018-05-18

 The supraclavicular artery flap is an excellent flap for head and neck reconstruction. The aim of this study is to assess imaging techniques to define the precise vascular boundaries of this flap.  Six imaging techniques were used for supraclavicular artery mapping in 65 cases; handheld Doppler, triplex ultrasound, computed tomography angiography, magnetic resonance angiography, digital subtraction angiography, and indocyanine green angiography. We checked the site of the perforators, the course of a supraclavicular artery, and anatomical mapping of the supraclavicular artery.  Handheld Doppler identified perforators' sites in 80% of the cases but showed no results for the course of the vessel. Triplex ultrasound identified the site of perforators in 52.9%, and partial mapping of the course of a supraclavicular artery in 64.7% of the cases. Computerized tomography angiography showed the site of perforators in 60%, and the course of supraclavicular artery completely in 45%, and partially in an additional 30%of the cases examined. Magnetic resonance angiography showed negative results for all parameters. Digital subtraction angiography showed the partial course of a supraclavicular artery in 62.5%, but showed no perforators. Indocyanine green angiography showed the site of perforators in 60% and a partial course of supraclavicular artery distal to perforators in 60%.Anatomical mapping of the vessel was possible with computerized tomography angiogram completely in 45%, and partially in 30%, and was also possible with indocyanine green angiography partially in 60%.  Computerized tomography angiography showed best results in the mapping of the supraclavicular artery, but with an inability to define the perforator perfusion territories, and also with risks of irradiation, while indocyanine green angiography is a good alternative as it could precisely map the superficial course of the artery and angiosomes, with no radiation exposure. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Coronary angiogram video compression for remote browsing and archiving applications.

PubMed

Ouled Zaid, Azza; Fradj, Bilel Ben

2010-12-01

In this paper, we propose a H.264/AVC based compression technique adapted to coronary angiograms. H.264/AVC coder has proven to use the most advanced and accurate motion compensation process, but, at the cost of high computational complexity. On the other hand, analysis of coronary X-ray images reveals large areas containing no diagnostically important information. Our contribution is to exploit the energy characteristics in slice equal size regions to determine the regions with relevant information content, to be encoded using the H.264 coding paradigm. The others regions, are compressed using fixed block motion compensation and conventional hard-decision quantization. Experiments have shown that at the same bitrate, this procedure reduces the H.264 coder computing time of about 25% while attaining the same visual quality. A subjective assessment, based on the consensus approach leads to a compression ratio of 30:1 which insures both a diagnostic adequacy and a sufficient compression in regards to storage and transmission requirements. Copyright © 2010 Elsevier Ltd. All rights reserved.

Computational fluid dynamics (CFD) using porous media modeling predicts recurrence after coiling of cerebral aneurysms

PubMed Central

Ishida, Fujimaro; Tsuji, Masanori; Furukawa, Kazuhiro; Shiba, Masato; Yasuda, Ryuta; Toma, Naoki; Sakaida, Hiroshi; Suzuki, Hidenori

2017-01-01

Objective This study aimed to predict recurrence after coil embolization of unruptured cerebral aneurysms with computational fluid dynamics (CFD) using porous media modeling (porous media CFD). Method A total of 37 unruptured cerebral aneurysms treated with coiling were analyzed using follow-up angiograms, simulated CFD prior to coiling (control CFD), and porous media CFD. Coiled aneurysms were classified into stable or recurrence groups according to follow-up angiogram findings. Morphological parameters, coil packing density, and hemodynamic variables were evaluated for their correlations with aneurysmal recurrence. We also calculated residual flow volumes (RFVs), a novel hemodynamic parameter used to quantify the residual aneurysm volume after simulated coiling, which has a mean fluid domain > 1.0 cm/s. Result Follow-up angiograms showed 24 aneurysms in the stable group and 13 in the recurrence group. Mann-Whitney U test demonstrated that maximum size, dome volume, neck width, neck area, and coil packing density were significantly different between the two groups (P < 0.05). Among the hemodynamic parameters, aneurysms in the recurrence group had significantly larger inflow and outflow areas in the control CFD and larger RFVs in the porous media CFD. Multivariate logistic regression analyses demonstrated that RFV was the only independently significant factor (odds ratio, 1.06; 95% confidence interval, 1.01–1.11; P = 0.016). Conclusion The study findings suggest that RFV collected under porous media modeling predicts the recurrence of coiled aneurysms. PMID:29284057

Development and Evaluation of Sterographic Display for Lung Cancer Screening

DTIC Science & Technology

2008-12-01

burden. Application of GPUs – With the evolution of commodity graphics processing units (GPUs) for accelerating games on personal computers, over the...units, which are designed for rendering computer games , are readily available and can be programmed to perform the kinds of real-time calculations...575-581, 1994. 12. Anderson CM, Saloner D, Tsuruda JS, Shapeero LG, Lee RE. "Artifacts in maximun-intensity-projection display of MR angiograms

Sensitivity and Specificity of OCT Angiography to Detect Choroidal Neovascularization.

PubMed

Faridi, Ambar; Jia, Yali; Gao, Simon S; Huang, David; Bhavsar, Kavita V; Wilson, David J; Sill, Andrew; Flaxel, Christina J; Hwang, Thomas S; Lauer, Andreas K; Bailey, Steven T

2017-01-01

To determine the sensitivity and specificity of optical coherence tomography angiography (OCTA) in the detection of choroidal neovascularization (CNV) in age-related macular degeneration (AMD). Prospective case series. Prospective series of seventy-two eyes were studied, which included eyes with treatment-naive CNV due to AMD, non-neovascular AMD, and normal controls. All eyes underwent OCTA with a spectral domain (SD) OCT (Optovue, Inc.). The 3D angiogram was segmented into separate en face views including the inner retinal angiogram, outer retinal angiogram, and choriocapillaris angiogram. Detection of abnormal flow in the outer retina served as candidate CNV with OCTA. Masked graders reviewed structural OCT alone, en face OCTA alone, and en face OCTA combined with cross-sectional OCTA for the presence of CNV. The sensitivity and specificity of CNV detection compared to the gold standard of fluorescein angiography (FA) and OCT was determined for structural SD-OCT alone, en face OCTA alone, and with en face OCTA combined with cross-sectional OCTA. Of 32 eyes with CNV, both graders identified 26 true positives with en face OCTA alone, resulting in a sensitivity of 81.3%. Four of the 6 false negatives had large subretinal hemorrhage (SRH) and sensitivity improved to 94% for both graders if eyes with SRH were excluded. The addition of cross-sectional OCTA along with en face OCTA improved the sensitivity to 100% for both graders. Structural OCT alone also had a sensitivity of 100%. The specificity of en face OCTA alone was 92.5% for grader A and 97.5% for grader B. The specificity of structural OCT alone was 97.5% for grader A and 85% for grader B. Cross-sectional OCTA combined with en face OCTA had a specificity of 97.5% for grader A and 100% for grader B. Sensitivity and specificity for CNV detection with en face OCTA combined with cross-sectional OCTA approaches that of the gold standard of FA with OCT, and it is better than en face OCTA alone. Structural OCT alone has excellent sensitivity for CNV detection. False positives from structural OCT can be mitigated with the addition of flow information with OCTA.

Sparse representations via learned dictionaries for x-ray angiogram image denoising

NASA Astrophysics Data System (ADS)

Shang, Jingfan; Huang, Zhenghua; Li, Qian; Zhang, Tianxu

2018-03-01

X-ray angiogram image denoising is always an active research topic in the field of computer vision. In particular, the denoising performance of many existing methods had been greatly improved by the widely use of nonlocal similar patches. However, the only nonlocal self-similar (NSS) patch-based methods can be still be improved and extended. In this paper, we propose an image denoising model based on the sparsity of the NSS patches to obtain high denoising performance and high-quality image. In order to represent the sparsely NSS patches in every location of the image well and solve the image denoising model more efficiently, we obtain dictionaries as a global image prior by the K-SVD algorithm over the processing image; Then the single and effectively alternating directions method of multipliers (ADMM) method is used to solve the image denoising model. The results of widely synthetic experiments demonstrate that, owing to learned dictionaries by K-SVD algorithm, a sparsely augmented lagrangian image denoising (SALID) model, which perform effectively, obtains a state-of-the-art denoising performance and better high-quality images. Moreover, we also give some denoising results of clinical X-ray angiogram images.

A level-set method for pathology segmentation in fluorescein angiograms and en face retinal images of patients with age-related macular degeneration

NASA Astrophysics Data System (ADS)

Mohammad, Fatimah; Ansari, Rashid; Shahidi, Mahnaz

2013-03-01

The visibility and continuity of the inner segment outer segment (ISOS) junction layer of the photoreceptors on spectral domain optical coherence tomography images is known to be related to visual acuity in patients with age-related macular degeneration (AMD). Automatic detection and segmentation of lesions and pathologies in retinal images is crucial for the screening, diagnosis, and follow-up of patients with retinal diseases. One of the challenges of using the classical level-set algorithms for segmentation involves the placement of the initial contour. Manually defining the contour or randomly placing it in the image may lead to segmentation of erroneous structures. It is important to be able to automatically define the contour by using information provided by image features. We explored a level-set method which is based on the classical Chan-Vese model and which utilizes image feature information for automatic contour placement for the segmentation of pathologies in fluorescein angiograms and en face retinal images of the ISOS layer. This was accomplished by exploiting a priori knowledge of the shape and intensity distribution allowing the use of projection profiles to detect the presence of pathologies that are characterized by intensity differences with surrounding areas in retinal images. We first tested our method by applying it to fluorescein angiograms. We then applied our method to en face retinal images of patients with AMD. The experimental results included demonstrate that the proposed method provided a quick and improved outcome as compared to the classical Chan-Vese method in which the initial contour is randomly placed, thus indicating the potential to provide a more accurate and detailed view of changes in pathologies due to disease progression and treatment.

Cardiac cycle-dependent left atrial dynamics: implications for catheter ablation of atrial fibrillation.

PubMed

Patel, Amit R; Fatemi, Omid; Norton, Patrick T; West, J Jason; Helms, Adam S; Kramer, Christopher M; Ferguson, John D

2008-06-01

Left atrial (LA) volume determines prognosis and response to therapy for atrial fibrillation. Integration of electroanatomic maps with three-dimensional images rendered from computed tomography and magnetic resonance imaging (MRI) is used to facilitate atrial fibrillation ablation. The purpose of this study was to measure LA volume changes and regional motion during the cardiac cycle that might affect the accuracy of image integration and to determine their relationship to standard LA volume measurements. MRI was performed in 30 patients with paroxysmal atrial fibrillation. LA time-volume curves were generated and used to divide LA ejection fraction into pumping ejection fraction and conduit ejection fraction and to determine maximum LA volume (LA(max)) and preatrial contraction volume. LA volume was measured using an MRI angiogram and traditional geometric models from echocardiography (area-length model and ellipsoid model). In-plane displacement of the pulmonary veins, anterior left atrium, mitral annulus, and LA appendage was measured. LA(max) was 107 +/- 36 mL and occurred at 42% +/- 5% of the R-R interval. Preatrial contraction volume was 86 +/- 34 mL and occurred at 81% +/- 4% of the R-R interval. LA ejection fraction was 45% +/- 10%, and pumping ejection fraction was 31% +/- 10%. LA volume measurements made from MRI angiogram, area-length model, and ellipsoid model underestimated LA(max) by 21 +/- 25 mL, 16 +/- 26 mL, and 35 +/- 22 mL, respectively. Anterior LA, mitral annulus, and LA appendage were significantly displaced during the cardiac cycle (8.8 +/- 2.0 mm, 13.2 +/- 3.8 mm, and 10.2 +/- 3.4 mm, respectively); the pulmonary veins were not displaced. LA volume changes significantly during the cardiac cycle, and substantial regional variation in LA motion exists. Standard measurements of LA volume significantly underestimate LA(max) compared to the gold standard measure of three-dimensional volumetrics.

CT Angiography of Peripheral Arterial Disease by 256-Slice Scanner: Accuracy, Advantages and Disadvantages Compared to Digital Subtraction Angiography.

PubMed

Mishra, Atul; Jain, Narendra; Bhagwat, Anand

2017-07-01

Peripheral arterial occlusive disease (PAOD) may cause disabling claudication or critical limb ischemia. Multidetector computed tomography (CT) technology has evolved to the level of 256-slice CT scanners which has significantly improved the spatial and temporal resolution of the images. This has provided the capability of chasing the contrast bolus at a fast speed enabling angiographic imaging of long segments of the body. These images can be reconstructed in various planes and various modes for detailed analysis of the peripheral vascular diseases which helps in making treatment decision. The aim of this retrospective study was to compare the CT angiograms (CTAs) of all cases of PAOD done by 256-slice CT scanner at a tertiary care vascular center and comparing these images with the digital subtraction angiograms (DSAs) of these patients. The retrospective study included 53 patients who underwent both CTA and DSA at our center over a period of 3 years from March 2013 to March 2016. The CTA showed high sensitivity (93%) and specificity (92.7%) for overall assessment of degree of stenosis in a vascular segment in cases of aortic and lower limb occlusive disease. The assessment of lesions of infrapopliteal segment was comparatively inferior (sensitivity 91.6%, accuracy 73.3%, and positive predictive value 78.5%), more so in the presence of significant calcification. The advantages of CTA were its noninvasive nature, ability to image large area of body, almost no adverse effects to the patients, and better assessment of vessel wall disease. However, the CTA assessment of collaterals was inferior with a sensitivity of only 62.7% as compared to DSA. Overall, 256-slice CTA provides fast and accurate imaging of vascular tree which can restrict DSA only in few selected cases as a problem-solving tool where clinico-radiological mismatch is present.

When are CT angiograms indicated for patients with lower extremity fractures? A review of 275 extremities.

PubMed

Monazzam, Shafagh; Goodell, Parker B; Salcedo, Edgardo S; Nelson, Sandahl H; Wolinsky, Philip R

2017-01-01

Computed tomography angiogram (CTA) is frequently utilized to detect vascular injuries even without examination findings indicating a vascular injury. We had the following hypotheses: (1) a CTA for lower extremity fractures with no clinical signs of a vascular injury is not indicated, and (2) fracture location and pattern would correlate with the risk of a vascular injury. A retrospective review was conducted on patients who had an acute lower extremity fracture(s) and a CTA. Their charts were reviewed for multiple factors including the presence or absence of hard or soft signs of a vascular injury, soft tissue status, and fracture location/pattern. Every CTA radiology report was reviewed and any vascular intervention or amputation resulting from a vascular injury was recorded. Statistical analysis was performed. Of the 275 CTAs of fractured extremities reviewed, 80 (29%) had a positive CTA finding and 16 (6%) required treatment. A total of 109 (40%) of the extremities had no hard or soft signs; all had normal CTAs. Having at least one hard or soft sign was a significant risk factor for having a positive CTA. An open fracture, isolated proximal third fibula fracture, distal and shaft tibia fractures, and the presence of multiple fractures in one extremity were also associated with an increased risk for having a positive CTA. We found no evidence to support the routine use of CTAs to evaluate lower extremity fractures unless at least one hard or soft sign is present. The presence of an open fracture, distal tibia or tibial shaft fractures, multiple fractures in one extremity, and/or an isolated proximal third fibula fracture increases the risk of having a finding consistent with a vascular injury on a CTA. Only 6% of the cases required treatment, and all of them had diminished or absent distal pulses on presentation. Diagnostic test, level III.

Effect of blood vessels on light distribution in optogenetic stimulation of cortex.

PubMed

Azimipour, Mehdi; Atry, Farid; Pashaie, Ramin

2015-05-15

In this Letter, the impact of blood vessels on light distribution during photostimulation of cortical tissue in small rodents is investigated. Brain optical properties were extracted using a double-integrating sphere setup, and optical coherence tomography was used to image cortical vessels and capillaries to generate a three-dimensional angiogram of the cortex. By combining these two datasets, a complete volumetric structure of the cortical tissue was developed and linked to a Monte Carlo code which simulates light propagation in this inhomogeneous structure and illustrates the effect of blood vessels on the penetration depth and pattern preservation in optogenetic stimulation.

Efficacy of Indocyanine Green Angiography on Microsurgical Subinguinal Varicocelectomy.

PubMed

Shibata, Yasuhiro; Kurihara, Sota; Arai, Seiji; Kato, Haruo; Suzuki, Tomomi; Miyazawa, Yoshiyuki; Koike, Hidekazu; Ito, Kazuto; Nakamura, Tetsuya; Suzuki, Kazuhiro

2017-08-01

Microsurgical subinguinal varicocelectomy is one of the best treatment modalities for varicoceles related to male infertility and scrotal pain. However, the difficulty in identifying testicular arteries, which should be spared, is a limitation of this technique. To visualize and identify the testicular arteries in spermatic cord during the operation, we examined the efficacy of intraoperative indocyanine green angiography (ICGA), which is regularly used in microsurgical neurosurgery. After the exposure of the spermatic cord blood vessels, ICG was injected intravenously under a surgical microscope for observing infrared fluorescence in patients to identify and isolate the testicular artery. The testicular artery was clearly identified by ICGA and was able to separate under ICGA view. Thereafter, the varicose veins were repeatedly ligated, while preserving a few lymphatic vessels and the spermatic duct. The preserved arteries were confirmed by repeated ICGA at the end of microsurgical operation. The number of arteries identified by ICGA was greater than the number detected by preoperative computed tomography angiogram. Microsurgical subinguinal varicocelectomy using intraoperative ICGA facilitated safe and quick surgery by enabling the visualization of the spermatic cord blood vessels. This is the first report to indicate the usefulness of vessel visualization by ICGA during microsurgical subinguinal varicocelectomy.

Likelihood of aneurysmal subarachnoid haemorrhage in patients with normal unenhanced CT, CSF xanthochromia on spectrophotometry and negative CT angiography.

PubMed

Rana, A K; Turner, H E; Deans, K A

2013-01-01

Patients with suspected subarachnoid haemorrhage, a normal noncontrast computed tomography (CT) and cerebrospinal fluid (CSF) evidence of haemoglobin breakdown products often undergo CT angiography (CTA). If this is normal, then invasive catheter angiography may be offered. In current clinical practice, haemoglobin breakdown products are detected by spectrophotometry rather than visible xanthochromia, and CTA is performed on multidetector scanners. The aim of this study was to determine if such patients should still have a catheter angiography, given the associated risks. Patients positive for CSF spectrophotometry (n=26) were retrospectively identified from the clinical biochemistry information system and imaging data from the electronic radiology records were reviewed. Discharge letters were consulted to relate the biochemistry and radiology results to the final diagnosis. 15 patients with CT angiography were found. Nine patients had normal CT angiography. No causative aneurysms had been missed. One patient had small, coincidental aneurysms missed on initial reading of the CTA. The likelihood of a clinically significant aneurysm in a patient who is CT negative, lumbar puncture positive and CTA negative is low. Double reporting of negative CT angiograms may be advisable.

Endovascular Therapy of Bronchial Artery Aneurysm: Five Cases With Six Aneurysms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lue, Peng-Hua, E-mail: whycn77@sina.com; Wang Lifu; Su Yusheng

2011-06-15

The objective of this study was to investigate the effect of transcatheter arterial embolization (TAE) with N-butyl-2-cyanoacrylate (NBCA)-Lipiodol mixture in patients with bronchial artery aneurysm (BAA). From January 2005 to January 2010, five patients presenting hemoptysis with six BAAs were treated with NBCA-Lipiodol mixture, including intra-aneurysm embolization (IAE) in one patient. Adjuvant embolization with spherical polyvinyl alcohol (PVA) embolic microparticles or NBCA was first performed to embolize the distal engorged bronchiectatic arteries. Bronchial arterial angiography showed six BAAs (four in the right lobe and two in the left lobe) and some engorged, tortuous bronchial arteries. TAE through microcatheter was successfulmore » in all cases. Postembolization angiogram demonstrated the NBCA cast and total occlusion of BAAs and bronchiectatic engorged vessels. After these procedures, hemoptysis completely disappeared in all patients. Follow-up computed tomography (CT) scan was performed at an average of 3 months (range 2 to 6), which showed no enhancement of BAAs and accumulation of NBCA. TAE is a minimally invasive, effective, and reliable approach for treatment for patients with BAA. NBCA-Lipiodol mixture provides a good choice for treatment of BAA, especially when catheterization of the efferent branches is impossible.« less

Digital image processing of vascular angiograms

NASA Technical Reports Server (NTRS)

Selzer, R. H.; Blankenhorn, D. H.; Beckenbach, E. S.; Crawford, D. W.; Brooks, S. H.

1975-01-01

A computer image processing technique was developed to estimate the degree of atherosclerosis in the human femoral artery. With an angiographic film of the vessel as input, the computer was programmed to estimate vessel abnormality through a series of measurements, some derived primarily from the vessel edge information and others from optical density variations within the lumen shadow. These measurements were combined into an atherosclerosis index, which was found to correlate well with both visual and chemical estimates of atherosclerotic disease.

Endovascular intervention for central venous cannulation in patients with vascular occlusion after previous catheterization.

PubMed

Pikwer, Andreas; Acosta, Stefan; Kölbel, Tilo; Åkeson, Jonas

2010-01-01

This study was designed to assess endovascular intervention for central venous cannulation in patients with vascular occlusion after previous catheterization. Patients referred for endovascular management of central venous occlusion during a 42-month period were identified from a regional endovascular database, providing prospective information on techniques and clinical outcome. Corresponding patient records, angiograms, and radiographic reports were analyzed retrospectively. Sixteen patients aged 48 years (range 0.5-76), including 11 females, were included. All patients but 1 had had multiple central venous catheters with a median total indwelling time of 37 months. Eleven patients cannulated for hemodialysis had had significantly fewer individual catheters inserted compared with 5 patients cannulated for nutritional support (mean 3.6 vs. 10.2, p<0.001) before endovascular intervention. Preoperative imaging by magnetic resonance tomography (MRT) in 8 patients, computed tomography (CT) venography in 3, conventional angiography in 6, and/or ultrasonography in 8, verified 15 brachiocephalic, 13 internal jugular, 3 superior caval, and/or 3 subclavian venous occlusions. Patients were subjected to recanalization (n=2), recanalization and percutaneous transluminal angioplasty (n=5), or stenting for vena cava superior syndrome (n=1) prior to catheter insertion. The remaining 8 patients were cannulated by avoiding the occluded route. Central venous occlusion occurs particularly in patients under hemodialysis and with a history of multiple central venous catheterizations with large-diameter catheters and/or long total indwelling time periods. Patients with central venous occlusion verified by CT or MRT venography and need for central venous access should be referred for endovascular intervention.

Optical Coherence Tomography Angiography Features of Diabetic Retinopathy

PubMed Central

Hwang, Thomas S.; Jia, Yali; Gao, Simon S.; Bailey, Steven T.; Lauer, Andreas K.; Flaxel, Christina J.; Wilson, David J.; Huang, David

2015-01-01

Purpose To describe the optical coherence tomography (OCT) angiography features of diabetic retinopathy Methods Using a 70kHz OCT and the split-spectrum amplitude decorrelation angiography (SSADA) algorithm, 6 × 6 mm 3-dimensional angiograms of the macula of 4 patients with diabetic retinopathy were obtained and compared with fluorescein angiography (FA) for features catalogued by the Early Treatment of Diabetic Retinopathy Study. Results OCT angiography detected enlargement and distortion of the foveal avascular zone, retinal capillary dropout, and pruning of arteriolar branches. Areas of capillary loss obscured by fluorescein leakage on FA were more clearly defined on OCT angiography. Some areas of focal leakage on FA that were thought to be microaneurysms were found to be small tufts of neovascularization that extended above the inner limiting membrane. Conclusion OCT angiography does not show leakage, but can better delineate areas of capillary dropout and detect early retinal neovascularization. This new noninvasive angiography technology may be useful for routine surveillance of proliferative and ischemic changes in diabetic retinopathy. PMID:26308529

Dynamic contrast optical coherence tomography images transit time and quantifies microvascular plasma volume and flow in the retina and choriocapillaris

PubMed Central

Merkle, Conrad W.; Leahy, Conor; Srinivasan, Vivek J.

2016-01-01

Despite the prevalence of optical imaging techniques to measure hemodynamics in large retinal vessels, quantitative measurements of retinal capillary and choroidal hemodynamics have traditionally been challenging. Here, a new imaging technique called dynamic contrast optical coherence tomography (DyC-OCT) is applied in the rat eye to study microvascular blood flow in individual retinal and choroidal layers in vivo. DyC-OCT is based on imaging the transit of an intravascular tracer dynamically as it passes through the field-of-view. Hemodynamic parameters can be determined through quantitative analysis of tracer kinetics. In addition to enabling depth-resolved transit time, volume, and flow measurements, the injected tracer also enhances OCT angiograms and enables clear visualization of the choriocapillaris, particularly when combined with a post-processing method for vessel enhancement. DyC-OCT complements conventional OCT angiography through quantification of tracer dynamics, similar to fluorescence angiography, but with the important added benefit of laminar resolution. PMID:27867732

Dynamic contrast optical coherence tomography images transit time and quantifies microvascular plasma volume and flow in the retina and choriocapillaris.

PubMed

Merkle, Conrad W; Leahy, Conor; Srinivasan, Vivek J

2016-10-01

Despite the prevalence of optical imaging techniques to measure hemodynamics in large retinal vessels, quantitative measurements of retinal capillary and choroidal hemodynamics have traditionally been challenging. Here, a new imaging technique called dynamic contrast optical coherence tomography (DyC-OCT) is applied in the rat eye to study microvascular blood flow in individual retinal and choroidal layers in vivo . DyC-OCT is based on imaging the transit of an intravascular tracer dynamically as it passes through the field-of-view. Hemodynamic parameters can be determined through quantitative analysis of tracer kinetics. In addition to enabling depth-resolved transit time, volume, and flow measurements, the injected tracer also enhances OCT angiograms and enables clear visualization of the choriocapillaris, particularly when combined with a post-processing method for vessel enhancement. DyC-OCT complements conventional OCT angiography through quantification of tracer dynamics, similar to fluorescence angiography, but with the important added benefit of laminar resolution.

Play dough as an educational tool for visualization of complicated cerebral aneurysm anatomy.

PubMed

Eftekhar, Behzad; Ghodsi, Mohammad; Ketabchi, Ebrahim; Ghazvini, Arman Rakan

2005-05-10

Imagination of the three-dimensional (3D) structure of cerebral vascular lesions using two-dimensional (2D) angiograms is one of the skills that neurosurgical residents should achieve during their training. Although ongoing progress in computer software and digital imaging systems has facilitated viewing and interpretation of cerebral angiograms enormously, these facilities are not always available. We have presented the use of play dough as an adjunct to the teaching armamentarium for training in visualization of cerebral aneurysms in some cases. The advantages of play dough are low cost, availability and simplicity of use, being more efficient and realistic in training the less experienced resident in comparison with the simple drawings and even angiographic views from different angles without the need for computers and similar equipment. The disadvantages include the psychological resistance of residents to the use of something in surgical training that usually is considered to be a toy, and not being as clean as drawings or computerized images. Although technology and computerized software using the patients' own imaging data seems likely to become more advanced in the future, use of play dough in some complicated cerebral aneurysm cases may be helpful in 3D reconstruction of the real situation.

Positron Emission Tomography - Computed Tomography (PET/CT)

MedlinePlus

... A-Z Positron Emission Tomography - Computed Tomography (PET/CT) Positron emission tomography (PET) uses small amounts of ... What is Positron Emission Tomography – Computed Tomography (PET/CT) Scanning? Positron emission tomography, also called PET imaging ...

Basilar artery hypoplasia associated with changes of brainstem potential, transcranial Doppler and perfusion-weighted imaging.

PubMed

Zhang, Dao Pei; Yin, Suo; Zhang, Shu Ling; Zhang, Jie Wen; Ma, Qian Kun; Lu, Gui Feng

2017-07-01

The aim of this study was to observe brainstem hemodynamic alterations associated with basilar artery hypoplasia (BAH). Nine hundred and fifty-two consecutive patients received emergency multimodal computed tomography; magnetic resonance imaging and magnetic resonance angiogram during the period of January 2011 to December 2014 were included. The vascular risk factors, brainstem auditory evoked potential (BAEP), blink reflex (BR), transcranial Doppler (TCD) and dynamic susceptibility contrast-enhanced perfusion-weighted imaging were completed. There was significant difference in the abnormal rates of TCD and BAEP between BAH and non-BAH patients. A positive correlation between basilar artery diameter and systolic velocity among BAH patients was suggested. V-wave value was used to predict posterior circulation infarction (PCI) with the sensitivity of 0.933 and specificity of 0.50 with the cutoff value of 5.97 s. Abnormal BR rate was also significantly different in BAH and non-BAH patients. The latency of R2 was used to predict PCI with the sensitivity of 0.933 and specificity of 0.50 with the cutoff value of 46.4 ms. The incidence of hypoperfusion was higher in BAH than non-BAH group and it was significant difference. BAH is closely associated with hemodynamic alterations within the pons, which might contribute to vascular vertigo due to regional hypoperfusion.

Clinical applications of three-dimensional tortuosity metrics

NASA Astrophysics Data System (ADS)

Dougherty, Geoff; Johnson, Michael J.

2007-03-01

The measurement of abnormal vascular tortuosity is important in the diagnosis of many diseases. Metrics based on three-dimensional (3-D) curvature, using approximate polynomial spline-fitting to "data balls" centered along the mid-line of the vessel, minimize digitization errors and give tortuosity values largely independent of the resolution of the imaging system. In order to establish their clinical validity we applied them to a number of clinical vascular systems, using both 2-D (standard angiograms and retinal images) and 3-D datasets (from computed tomography angiography (CTA) and magnetic resonance angiography (MRA)). Using the abdominal aortograms we found that the metrics correlated well with the ranking of an expert panel of three vascular surgeons. Both the mean curvature and the root-mean square curvature provided good discrimination between vessels of different tortuosity: and using a data ball size of one-quarter of the local vessel radius in the spline fitting gave consistent results. Tortuous retinal vessels resulting from retinitis or diabetes, but not from vasculitis, could be distinguished from normal vessels. Tortuosity values based on 3-D data sets gave higher values than their 2-D projections, and could easily be implemented in automatic measurement. They produced values sufficiently discriminating to assess the relative utility of arteries for endoluminal repair of aneurysms.

The introduction of capillary structures in 4D simulated vascular tree for ART 3.5D algorithm further validation

NASA Astrophysics Data System (ADS)

Barra, Beatrice; El Hadji, Sara; De Momi, Elena; Ferrigno, Giancarlo; Cardinale, Francesco; Baselli, Giuseppe

2017-03-01

Several neurosurgical procedures, such as Artero Venous Malformations (AVMs), aneurysm embolizations and StereoElectroEncephaloGraphy (SEEG) require accurate reconstruction of the cerebral vascular tree, as well as the classification of arteries and veins, in order to increase the safety of the intervention. Segmentation of arteries and veins from 4D CT perfusion scans has already been proposed in different studies. Nonetheless, such procedures require long acquisition protocols and the radiation dose given to the patient is not negligible. Hence, space is open to approaches attempting to recover the dynamic information from standard Contrast Enhanced Cone Beam Computed Tomography (CE-CBCT) scans. The algorithm proposed by our team is called ART 3.5 D. It is a novel algorithm based on the postprocessing of both the angiogram and the raw data of a standard Digital Subtraction Angiography from a CBCT (DSACBCT) allowing arteries and veins segmentation and labeling without requiring any additional radiation exposure for the patient and neither lowering the resolution. In addition, while in previous versions of the algorithm just the distinction of arteries and veins was considered, here the capillary phase simulation and identification is introduced, in order to increase further information useful for more precise vasculature segmentation.

Levitronix bilateral ventricular assist device, a bridge to recovery in a patient with acute fulminant myocarditis and concomitant cerebellar infarction.

PubMed

Huang, Yi-Fan; Hsu, Po-Shun; Tsai, Chien-Sung; Tsai, Yi-Ting; Lin, Chih-Yuan; Ke, Hong-Yan; Lin, Yi-Chang; Yang, Hsiang-Yu

2018-02-07

We report on the case of a 27-year-old male who presented to our emergency room with chest tightness, dyspnoea and cold sweats. The 12-lead electrocardiogram showed diffuse ventricular tachycardia with wide QRS complexes. Troponin-I level was elevated to 100 ng/ml. The coronary angiogram showed good patency of all three coronary vessels, and acute fulminant myocarditis was suspected. The patient underwent cardiopulmonary resuscitation in the catheter room and high-dose inotropic support was initiated to stabilise his haemodynamic status. After resuscitation, the patient was in a coma and acute stroke was highly suspected. In addition, deteriorating cardiogenic shock with acute renal failure and pulmonary oedema were also detected. Due to haemodynamic compromise despite high-dose inotropic support, a Levitronix ® bilateral ventricular assist device (Bi-VAD) was implanted on an emergency basis for circulatory support. Postoperative brain computed tomography revealed acute left cerebellar infarction. Because the patient had left cerebellar infarction with right hemiplegia, heart transplantation was contraindicated. Eventually, cardiac systolic function recovered well and the patient underwent successful Bi-VAD removal after a total of 18 days on Levitronix ® haemodynamic support. He was weaned from the ventilator two weeks later and was discharged 10 days later.

MDCT diagnosis of post-traumatic hepatic arterio-portal fistulas.

PubMed

Nguyen, Cuong T; Nguyen, Coung; Saksobhavivat, Nitima; Saksobahavivat, Nitima; Shanmuganathan, Kathirkamanathan; Steenburg, Scott D; Steenburg, Scott; Moeslein, Fred M; Moeslein, Fred; Mirvis, Stuart E; Chiu, William

2013-06-01

The purpose of this study is to evaluate the performance of multidetector computed tomography (MDCT) in diagnosing arterioportal fistulas (APF) in high-grade liver injury. A retrospective analysis of catheter-based hepatic angiograms performed for major penetrating and blunt liver injuries identified 11 patients with APFs. Using the trauma registry, two additional demographically matched groups with and without liver injury were formed. A randomized qualitative consensus review of 33 MDCTs was performed by three trauma radiologists for the following MDCT findings of APF: transient hepatic parenchymal attenuation differences (THPAD), early increased attenuation of a peripheral or central portal vein compared with the main portal vein, and the "double-barrel" or "rail tract" signs. THPAD was the most sensitive finding and also had a high specificity for diagnosing APF. Both the early increased attenuation of a peripheral or central portal vein compared with the main portal vein and the double-barrel or rail tract signs had a100% specificity and a sensitivity of 64% and 36%, respectively. Measurement of differences in attenuation values between the APF and the contralateral central portal vein was most sensitive and specific in diagnosing APF. Traumatic APF of the liver can be optimally diagnosed with arterial phase imaging of solid organ using MDCT.

A pilot audit of a protocol for ambulatory investigation of predicted low-risk patients with possible pulmonary embolism.

PubMed

McDonald, A H; Murphy, R

2011-09-01

Patients with possible pulmonary embolism (PE) commonly present to acute medical services. Research has led to the identification of low-risk patients suitable for ambulatory management. We report on a protocol designed to select low-risk patients for ambulatory investigation if confirmatory imaging is not available that day. The protocol was piloted in the Emergency Department and Medical Assessment Area at the Royal Infirmary of Edinburgh. We retrospectively analysed electronic patient records in an open observational audit of all patients managed in the ambulatory arm over five months of use. We analysed 45 patients' records. Of these, 91.1% required imaging to confirm or refute PE, 62.2% received a computed tomography pulmonary angiogram (CTPA). In 25% of patients, PE was confirmed with musculoskeletal pain (22.7%), and respiratory tract infection (15.9%) the next most prevalent diagnoses. Alternative diagnoses was provided by CTPA in 32% of cases. We identified no adverse events or readmissions but individualised follow-up was not attempted. The data from this audit suggests this protocol can be applied to select and manage low-risk patients suitable for ambulatory investigation of possible PE. A larger prospective comparative study would be required to accurately define the safety and effectiveness of this protocol.

Congenital Spondylolytic Spondylolisthesis of C2 Vertebra Associated With Atlanto-Axial Dislocation, Chiari Type I Malformation, and Anomalous Vertebral Artery: Case Report With Review Literature.

PubMed

Sardhara, Jayesh; Pavaman, Sindgikar; Das, Kuntal; Srivastava, Arun; Mehrotra, Anant; Behari, Sanjay

2016-11-01

Congenital spondylolytic spondylolisthesis of C2 vertebra resulting from deficient posterior element of the axis is rarely described in the literature. We describe a unique case of agenesis of posterior elements of C2 with craniovertebral junction anomalies consisting of osseous, vascular, and soft tissue anomalies. A 26-year-old man presented with symptoms of upper cervical myelopathy of 12 months' duration. A computed tomography scan of the cervical spine including the craniovertebral junction revealed spondylolisthesis of C2 over C3, atlantoaxial dislocation, occipitalization of the atlas, hypoplasia of the odontoid, and cleft posterior C1 arch. Additionally, the axis vertebra was found devoid of its posterior elements except bilaterally rudimentary pedicles. Magnetic resonance imaging revealed tonsilar herniation, suggesting associated Chiari type I malformation. CT angiogram of the vertebral arteries displayed persistent bilateral first intersegmental arteries crossing the posterior aspect of the C1/2 facet joint. This patient underwent foramen magnum decompression, C3 laminectomy with occipito-C3/C4 posterior fusion using screw and rod to maintain the cervical alignment and stability. We report this rare constellation of congenital craniovertebral junction anomaly and review the relevant literature. Copyright © 2016 Elsevier Inc. All rights reserved.

Time-Dependent Computed Tomographic Perfusion Thresholds for Patients With Acute Ischemic Stroke.

PubMed

d'Esterre, Christopher D; Boesen, Mari E; Ahn, Seong Hwan; Pordeli, Pooneh; Najm, Mohamed; Minhas, Priyanka; Davari, Paniz; Fainardi, Enrico; Rubiera, Marta; Khaw, Alexander V; Zini, Andrea; Frayne, Richard; Hill, Michael D; Demchuk, Andrew M; Sajobi, Tolulope T; Forkert, Nils D; Goyal, Mayank; Lee, Ting Y; Menon, Bijoy K

2015-12-01

Among patients with acute ischemic stroke, we determine computed tomographic perfusion (CTP) thresholds associated with follow-up infarction at different stroke onset-to-CTP and CTP-to-reperfusion times. Acute ischemic stroke patients with occlusion on computed tomographic angiography were acutely imaged with CTP. Noncontrast computed tomography and magnectic resonance diffusion-weighted imaging between 24 and 48 hours were used to delineate follow-up infarction. Reperfusion was assessed on conventional angiogram or 4-hour repeat computed tomographic angiography. Tmax, cerebral blood flow, and cerebral blood volume derived from delay-insensitive CTP postprocessing were analyzed using receiver-operator characteristic curves to derive optimal thresholds for combined patient data (pooled analysis) and individual patients (patient-level analysis) based on time from stroke onset-to-CTP and CTP-to-reperfusion. One-way ANOVA and locally weighted scatterplot smoothing regression was used to test whether the derived optimal CTP thresholds were different by time. One hundred and thirty-two patients were included. Tmax thresholds of >16.2 and >15.8 s and absolute cerebral blood flow thresholds of <8.9 and <7.4 mL·min(-1)·100 g(-1) were associated with infarct if reperfused <90 min from CTP with onset <180 min. The discriminative ability of cerebral blood volume was modest. No statistically significant relationship was noted between stroke onset-to-CTP time and the optimal CTP thresholds for all parameters based on discrete or continuous time analysis (P>0.05). A statistically significant relationship existed between CTP-to-reperfusion time and the optimal thresholds for cerebral blood flow (P<0.001; r=0.59 and 0.77 for gray and white matter, respectively) and Tmax (P<0.001; r=-0.68 and -0.60 for gray and white matter, respectively) parameters. Optimal CTP thresholds associated with follow-up infarction depend on time from imaging to reperfusion. © 2015 American Heart Association, Inc.

The application of optical coherence tomography angiography in retinal diseases.

PubMed

Sambhav, Kumar; Grover, Sandeep; Chalam, Kakarla V

Optical coherence tomography angiography (OCTA) is a new, noninvasive imaging technique that generates real-time volumetric data on chorioretinal vasculature and its flow pattern. With the advent of high-speed optical coherence tomography, established enface chorioretinal segmentation, and efficient algorithms, OCTA generates images that resemble an angiogram. The principle of OCTA involves determining the change in backscattering between consecutive B-scans and then attributing the differences to the flow of erythrocytes through retinal blood vessels. OCTA has shown promise in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age-related macular degeneration, and retinal vascular occlusions. It quantifies vascular compromise reflecting the severity of diabetic retinopathy. OCTA detects the presence of choroidal neovascularization in exudative age-related macular degeneration and maps loss of choriocapillaris in nonexudative age-related macular degeneration. We describe principles of OCTA and findings in common and some uncommon retinal pathologies. Finally, we summarize its potential future applications. Its current limitations include a relatively small field of view, inability to show leakage, and a tendency for image artifacts. Further larger studies will define OCTAs utility in clinical settings and establish if the technology may offer its utility in decreasing morbidity through early detection and guide therapeutic interventions in retinal diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Relationship between the Self-Rating Anxiety Scale score and the success rate of 64-slice computed tomography coronary angiography.

PubMed

Li, Hui; Jin, Dan; Qiao, Fang; Chen, Jianchang; Gong, Jianping

Computed tomography coronary angiography, a key method for obtaining coronary artery images, is widely used to screen for coronary artery diseases due to its noninvasive nature. In China, 64-slice computed tomography systems are now the most common models. As factors that directly affect computed tomography performance, heart rate and rhythm control are regulated by the autonomic nervous system and are highly related to the emotional state of the patient. The aim of this prospective study is to use a pre-computed tomography scan Self-Rating Anxiety Scale assessment to analyze the effects of tension and anxiety on computed tomography coronary angiography success. Subjects aged 18-85 years who were planned to undergo computed tomography coronary angiography were enrolled; 1 to 2 h before the computed tomography scan, basic patient data (gender, age, heart rate at rest, and family history) and Self-Rating Anxiety Scale score were obtained. The same group of imaging department doctors, technicians, and nurses performed computed tomography coronary angiography for all the enrolled subjects and observed whether those subjects could finish the computed tomography coronary angiography scan and provide clear, diagnostically valuable images. Participants were divided into successful (obtained diagnostically useful coronary images) and unsuccessful groups. Basic data and Self-Rating Anxiety Scale scores were compared between the groups. The Self-Rating Anxiety Scale standard score of the successful group was lower than that of the unsuccessful group (P = 0.001). As the Self-Rating Anxiety Scale standard score rose, the success rate of computed tomography coronary angiography decreased. The Self-Rating Anxiety Scale score has a negative relationship with computed tomography coronary angiography success. Anxiety can be a disadvantage in computed tomography coronary angiography examination. The pre-computed tomography coronary angiography scan Self-Rating Anxiety Scale score may be a useful tool for assessing whether a computed tomography coronary angiography scan will be successful or not. © The Author(s) 2015.

Computed Tomography (CT) - Spine

MedlinePlus

... Resources Professions Site Index A-Z Computed Tomography (CT) - Spine Computed tomography (CT) of the spine is ... of CT Scanning of the Spine? What is CT Scanning of the Spine? Computed tomography, more commonly ...

Complex signal-based optical coherence tomography angiography enables in vivo visualization of choriocapillaris in human choroid

NASA Astrophysics Data System (ADS)

Chu, Zhongdi; Chen, Chieh-Li; Zhang, Qinqin; Pepple, Kathryn; Durbin, Mary; Gregori, Giovanni; Wang, Ruikang K.

2017-12-01

The choriocapillaris (CC) plays an essential role in maintaining the normal functions of the human eye. There is increasing interest in the community to develop an imaging technique for visualizing the CC, yet this remains underexplored due to technical limitations. We propose an approach for the visualization of the CC in humans via a complex signal-based optical microangiography (OMAG) algorithm, based on commercially available spectral domain optical coherence tomography (SD-OCT). We show that the complex signal-based OMAG was superior to both the phase and amplitude signal-based approaches in detailing the vascular lobules previously seen with histological analysis. With this improved ability to visualize the lobular vascular networks, it is possible to identify the feeding arterioles and draining venules around the lobules, which is important in understanding the role of the CC in the pathogenesis of ocular diseases. With built-in FastTrac™ and montage scanning capabilities, we also demonstrate wide-field SD-OCT angiograms of the CC with a field of view at 9×11 mm2.

Play dough as an educational tool for visualization of complicated cerebral aneurysm anatomy

PubMed Central

Eftekhar, Behzad; Ghodsi, Mohammad; Ketabchi, Ebrahim; Ghazvini, Arman Rakan

2005-01-01

Background Imagination of the three-dimensional (3D) structure of cerebral vascular lesions using two-dimensional (2D) angiograms is one of the skills that neurosurgical residents should achieve during their training. Although ongoing progress in computer software and digital imaging systems has facilitated viewing and interpretation of cerebral angiograms enormously, these facilities are not always available. Methods We have presented the use of play dough as an adjunct to the teaching armamentarium for training in visualization of cerebral aneurysms in some cases. Results The advantages of play dough are low cost, availability and simplicity of use, being more efficient and realistic in training the less experienced resident in comparison with the simple drawings and even angiographic views from different angles without the need for computers and similar equipment. The disadvantages include the psychological resistance of residents to the use of something in surgical training that usually is considered to be a toy, and not being as clean as drawings or computerized images. Conclusion Although technology and computerized software using the patients' own imaging data seems likely to become more advanced in the future, use of play dough in some complicated cerebral aneurysm cases may be helpful in 3D reconstruction of the real situation. PMID:15885141

Model-based morphological segmentation and labeling of coronary angiograms.

PubMed

Haris, K; Efstratiadis, S N; Maglaveras, N; Pappas, C; Gourassas, J; Louridas, G

1999-10-01

A method for extraction and labeling of the coronary arterial tree (CAT) using minimal user supervision in single-view angiograms is proposed. The CAT structural description (skeleton and borders) is produced, along with quantitative information for the artery dimensions and assignment of coded labels, based on a given coronary artery model represented by a graph. The stages of the method are: 1) CAT tracking and detection; 2) artery skeleton and border estimation; 3) feature graph creation; and iv) artery labeling by graph matching. The approximate CAT centerline and borders are extracted by recursive tracking based on circular template analysis. The accurate skeleton and borders of each CAT segment are computed, based on morphological homotopy modification and watershed transform. The approximate centerline and borders are used for constructing the artery segment enclosing area (ASEA), where the defined skeleton and border curves are considered as markers. Using the marked ASEA, an artery gradient image is constructed where all the ASEA pixels (except the skeleton ones) are assigned the gradient magnitude of the original image. The artery gradient image markers are imposed as its unique regional minima by the homotopy modification method, the watershed transform is used for extracting the artery segment borders, and the feature graph is updated. Finally, given the created feature graph and the known model graph, a graph matching algorithm assigns the appropriate labels to the extracted CAT using weighted maximal cliques on the association graph corresponding to the two given graphs. Experimental results using clinical digitized coronary angiograms are presented.

Clinical value of whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of metastatic bladder cancer.

PubMed

Yang, Zhongyi; Pan, Lingling; Cheng, Jingyi; Hu, Silong; Xu, Junyan; Ye, Dingwei; Zhang, Yingjian

2012-07-01

To investigate the value of whole-body fluorine-18 2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for the detection of metastatic bladder cancer. From December 2006 to August 2010, 60 bladder cancer patients (median age 60.5 years old, range 32-96) underwent whole body positron emission tomography/computed tomography positron emission tomography/computed tomography. The diagnostic accuracy was assessed by performing both organ-based and patient-based analyses. Identified lesions were further studied by biopsy or clinically followed for at least 6 months. One hundred and thirty-four suspicious lesions were identified. Among them, 4 primary cancers (2 pancreatic cancers, 1 colonic and 1 nasopharyngeal cancer) were incidentally detected, and the patients could be treated on time. For the remaining 130 lesions, positron emission tomography/computed tomography detected 118 true positive lesions (sensitivity = 95.9%). On the patient-based analysis, the overall sensitivity and specificity resulted to be 87.1% and 89.7%, respectively. There was no difference of sensitivity and specificity in patients with or without adjuvant treatment in terms of detection of metastatic sites by positron emission tomography/computed tomography. Compared with conventional imaging modality, positron emission tomography/computed tomography correctly changed the management in 15 patients (25.0%). Positron emission tomography/computed tomography has excellent sensitivity and specificity in the detection of metastatic bladder cancer and it provides additional diagnostic information compared to standard imaging techniques. © 2012 The Japanese Urological Association.

Acute disseminated melioidosis giving rise to pneumonia and renal abscesses complicated with thrombotic thrombocytopenic purpura in a post partum woman: a case report.

PubMed

Wijewickrama, Piyumi Sachindra Alwis; Weerakoon, Rohini

2017-11-29

Melioidosis is an established endemic infection in Sri Lanka, caused by Burkholderia pseudomallei, a gram negative bacterium distributed in saprophytes in soil and surface water. Main mode of transmission is via percutaneous inoculation. Pneumonia is the most common presentation in acute disease. We report a 33 year old previously healthy Sinhalese female with an occupational exposure to surface water in paddy fields, who was on postpartum day 6 following an uncomplicated pregnancy and delivery via an elective caesarian section. She presented with a 1 day history of breathlessness, preceded by a brief episode of fever. She had occasional right side coarse crackles and pitting oedema of both lower limbs. Shortly after admission, she developed type one respiratory failure needing invasive mechanical ventilation. Initial chest x-ray revealed slight obliteration of right medial diaphragmatic border while echocardiogram revealed moderate pulmonary hypertension. Computed tomography pulmonary angiogram excluded a pulmonary embolism, but revealed bilateral multi-lobar consolidation. Abdominal computed tomography demonstrated bilateral pyelonephritis with renal abscesses. As initial cultures were inconclusive, melioidosis antibody levels were done due to high degree of suspicion, which was found to be positive with a titer of 1:2560. A diagnosis of melioidosis was made based on the suggestive clinical picture, exposure history and the highly positive antibody level. She developed left side focal seizures together with thrombocytopenia and microangiopathic haemolytic anemia, suggestive of thrombotic thrombocytopenic purpura. Magnetic resonance imaging of brain was negative for cerebral abscesses but revealed extensive minute haemorrhagic foci throughout the cerebrum. Thus, the final diagnosis was acute melioidosis causing pneumonia and renal abscesses, complicated with thrombotic thrombocytopenic purpura and sepsis. She demonstrated dramatic response to high dose meropenem and co-trimoxazole along with plasmapheresis. Four weeks after treatment, the antibody titer came down to 1:320. Melioidosis antibody was absent in the baby. This case was challenging as it was an atypical presentation of melioidosis during postpartum leading to a diagnostic conundrum. This highlights the need to look into the effect of pregnancy and postpartum as added risk factors. High index of suspicion is necessary to avoid diagnostic delays.

Prognosis of untreated strokes due to anterior circulation proximal intracranial arterial occlusions detected by use of computed tomography angiography.

PubMed

Lima, Fabricio O; Furie, Karen L; Silva, Gisele S; Lev, Michael H; Camargo, Erica C S; Singhal, Aneesh B; Harris, Gordon J; Halpern, Elkan F; Koroshetz, Walter J; Smith, Wade S; Nogueira, Raul G

2014-02-01

Limited data exist regarding the natural history of proximal intracranial arterial occlusions. OBJECTIVE To investigate the outcomes of patients who had an acute ischemic stroke attributed to an anterior circulation proximal intracranial arterial occlusion. A prospective cohort study at 2 university-based hospitals from 2003 to 2005 in which nonenhanced computed tomography scans and computed tomography angiograms were obtained at admission of all adult patients suspected of having an ischemic stroke in the first 24 hours of symptom onset. Anterior circulation proximal intracranial arterial occlusion. Frequency of good outcome (defined as a modified Rankin Scale score of ≤ 2) and mortality at 6 months. A total of 126 patients with a unilateral complete occlusion of the intracranial internal carotid artery (ICA; 26 patients: median National Institutes of Health Stroke Scale [NIHSS] score, 11 [interquartile range, 5-17]), of the M1 segment of the middle cerebral artery (MCA; 52 patients: median NIHSS score, 13 [interquartile range, 6-16]), or of the M2 segment of the MCA (48 patients: median NIHSS score, 7 [interquartile range, 4-15]) were included. Of these 3 groups of patients, 10 (38.5%), 20 (38.5%), and 26 (54.2%) with ICA, MCA-M1, and MCA-M2 occlusions, respectively, achieved a modified Rankin Scale score of 2 or less, and 6 (23.1%), 12 (23.1%), and 10 (20.8%) were dead at 6 months. Worse outcomes were seen in patients with a baseline NIHSS score of 10 or higher, with a modified Rankin Scale score of 2 or less achieved in only 7.1% (1 of 14), 23.5% (8 of 34), and 22.7% (5 of 22) of patients and mortality rates of 35.7% (5 of 14), 32.4% (11 of 34), and 40.9% (9 of 22) among patients with ICA, MCA-M1, and MCA-M2 occlusions, respectively. Age (odds ratio, 0.94 [95% CI, 0.91-0.98]), NIHSS score (odds ratio, 0.73 [95% CI, 0.64-0.83]), and strength of leptomeningeal collaterals (odds ratio, 2.37 [95% CI, 1.08-5.20]) were independently associated with outcome, whereas the level of proximal intracranial arterial occlusion (ICA vs MCA-M1 vs MCA-M2) was not. The natural history of proximal intracranial arterial occlusion is variable, with poor outcomes overall. Stroke severity and collateral flow appear to be more important than the level of proximal intracranial arterial occlusion in determining outcomes. Our results provide useful data for proper patient selection and sample size calculations in the design of new clinical trials aimed at recanalization therapies.

[Diagnostic possibilities of digital volume tomography].

PubMed

Lemkamp, Michael; Filippi, Andreas; Berndt, Dorothea; Lambrecht, J Thomas

2006-01-01

Cone beam computed tomography allows high quality 3D images of cranio-facial structures. Although detail resolution is increased, x-ray exposition is reduced compared to classic computer tomography. The volume is analysed in three orthogonal plains, which can be rotated independently without quality loss. Cone beam computed tomography seems to be a less expensive and less x-ray exposing alternative to classic computer tomography.

Coronary artery wall imaging.

PubMed

Keegan, Jennifer

2015-05-01

Like X-Ray contrast angiography, MR coronary angiograms show the vessel lumens rather than the vessels themselves. Consequently, outward remodeling of the vessel wall, which occurs in subclinical coronary disease before luminal narrowing, cannot be seen. The current gold standard for assessing the coronary vessel wall is intravascular ultrasound, and more recently, optical coherence tomography, both of which are invasive and use ionizing radiation. A noninvasive, low-risk technique for assessing the vessel wall would be beneficial to cardiologists interested in the early detection of preclinical disease and for the safe monitoring of the progression or regression of disease in longitudinal studies. In this review article, the current state of the art in MR coronary vessel wall imaging is discussed, together with validation studies and recent developments. © 2014 Wiley Periodicals, Inc.

Acute eclipse retinopathy: a small case series.

PubMed

Khatib, Nur; Knyazer, Boris; Lifshitz, Tova; Levy, Jaime

2014-01-01

We present four young patients with acute severe solar retinopathy after observation of the total eclipse on January 4, 2011 without appropriate eye protection. Funduscopic findings were accompanied by optical coherence tomography (OCT) investigation of the macula. All our patients were young (range 14-29 years). In three of the four patients we have been able to repeat OCT evaluation revealing that the retinal changes were reversible, but delineating mild pathology in the retinal pigment epithelium and photoreceptors. Best-corrected visual acuity in the fourth case was 6/24. In addition, macular edema, which has been previously described in literature, could not be demonstrated by OCT. In the two cases we performed an early fluorescein angiogram, no pathology was seen. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

CT angiography - chest

MedlinePlus

... aortic aneurysm - CTA chest; Venous thromboembolism - CTA lung; Blood clot - CTA lung; Embolus - CTA lung; CT pulmonary angiogram ... angiogram may be done: For symptoms that suggest blood clots in the lungs, such as chest pain, rapid ...

The identification of the variation of atherosclerosis plaques by invasive and non-invasive methods

NASA Technical Reports Server (NTRS)

Selzer, R. H.; Blankenhorn, D. H.

1982-01-01

Computer-enhanced visualization of coronary arteries and lesions within them is discussed, comparing invasive and noninvasive methods. Trial design factors in computer lesions assessment are briefly discussed, and the use of the computer edge-tracking technique in that assessment is described. The results of a small pilot study conducted on serial cineangiograms of men with premature atherosclerosis are presented. A canine study to determine the feasibility of quantifying atherosclerosis from intravenous carotid angiograms is discussed. Comparative error for arterial and venous injection in the canines is determined, and the mode of processing the films to achieve better visualization is described. The application of the computer edge-tracking technique to an ultrasound image of the human carotid artery is also shown and briefly discussed.

Cardiac arrest at high elevation with a favorable outcome.

PubMed

Yanagawa, Youichi; Omori, Kazuhiko; Takeuchi, Ikuto; Jitsuiki, Kei; Yoshizawa, Toshihiko; Ishikawa, Kouhei; Kando, Yumi; Fukata, Mutsumu; Ohsaka, Hiromichi

2017-04-01

A 36-year-old man started to climb Mount Fuji (3776m above sea level: ASL), from the Gotemba new fifth station (2400m ASL). He had no significant medical history, and this was his first attempt to climb such a high mountain. He began feeling chest discomfort but continued to climb. When he reached the ninth station of the mountain (3600mASL), he lost consciousness. One individual immediately provided basic life support using an automated external defibrillator (AED) that was located in the station. After electroshocks, he regained consciousness. He was transported to the fifth station, where an ambulance could approach, in a large crawler. When the medical staff, who were transported via helicopter and ambulance, examined him near the fifth station, he still complained of chest discomfort. A single spray of nitroglycerin and aspirin (200mg) was administered. He was transported to the Cardiac Care Unit via ambulance and helicopter under escort by a physician. A chest computed tomography angiogram indicated triple-vessel disease. He was discharged without any neurological deficits after undergoing bypass surgery. In high mountains that can be easily accessed by amateur climbers who may have cardiac disease, the placement of AED devices and the establishment of the chain of survival from the scene to the intensive care unit are essential for obtaining a favorable outcome when a climber suffers cardiac arrest. Copyright © 2016 Elsevier Inc. All rights reserved.

Page Kidney in Wunderlich Syndrome Causing Acute Renal Failure and Urosepsis: Successful Timely Minimally Invasive Management of a Devastating Clinical Entity.

PubMed

Vijayganapathy, Sundaramoorthy; Karthikeyan, Vilvapathy Senguttuvan; Mallya, Ashwin; Sreenivas, Jayaram

2017-06-01

Wunderlich Syndrome (WS) is an uncommon condition where acute onset of spontaneous bleeding occurs into the subcapsular and perirenal spaces. It can prove fatal if not recognized and treated aggressively at the appropriate time. A 32-year-old male diagnosed elsewhere as acute renal failure presented with tender left loin mass, fever and hypovolemic shock with serum creatinine 8.4 mg/dl. He was started on higher antibiotics and initiated on haemodialysis. Ultrasonogram (USG), Non-Contrast Computed Tomography (NCCT) and Magnetic Resonance Imaging (MRI) showed bilateral perirenal subcapsular haematomas - right 3.6 x 3.1 cm and left 10.3 x 10.3 cm compressing and displacing left kidney, fed by capsular branch of left renal artery on CT angiogram. Initial aspirate was bloody but he persisted to have febrile spikes, renal failure and urosepsis and he was managed conservatively. Repeat NCCT 10 days later revealed left perinephric abscess and Percutaneous Drainage (PCD) was done. Patient improved, serum creatinine stabilized at 2 mg/dl without haemodialysis and PCD was removed after two weeks. To conclude, bilateral idiopathic spontaneous retroperitoneal haemorrhage with renal failure is a rare presentation. This case highlights the need for high index of suspicion, the role of repeated imaging and successful minimally invasive management with timely PCD and supportive care.

Early Predictors of Fever in Patients with Aneurysmal Subarachnoid Hemorrhage.

PubMed

Rocha Ferreira da Silva, Ivan; Rodriguez de Freitas, Gabriel

2016-12-01

Fever is commonly observed in patients who have had aneurysmal subarachnoid hemorrhage (SAH), and it has been associated with the occurrence of delayed cerebral ischemia and worse outcomes in previous studies. Frequently, fever is not the result of bacterial infections, and distinction between infection-related fever and fever secondary to brain injury (also referred as central fever) can be challenging. The current study aimed to identify risk factors on admission for the development of central fever in patients with SAH. Databank analysis was performed using information from demographic data (age, gender), imaging (transcranial Doppler ultrasound, computed tomography, and cerebral angiogram), laboratory (white blood cell count, hemoglobin, renal function, and electrolytes), and clinical assessment (Hunt-Hess and modified Fisher scales on admission, occurrence of fever). A multivariate logistic regression model was created. Of 55 patients, 32 developed fever during the first 7 days of hospital stay (58%). None of the patients had identifiable bacterial infections during their first week in the neurocritical care unit. Hunt-Hess scale >2 and leukocytosis on admission were associated to the development of central fever, even after correction in a logistic regression model. Leukocytosis and a poor neurologic examination on admission might help predict which subset of patients with SAH are at higher risk of developing central fever early in their hospital stay. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Relative cerebral blood volume is associated with collateral status and infarct growth in stroke patients in SWIFT PRIME.

PubMed

Arenillas, Juan F; Cortijo, Elisa; García-Bermejo, Pablo; Levy, Elad I; Jahan, Reza; Goyal, Mayank; Saver, Jeffrey L; Albers, Gregory W

2017-01-01

We aimed to evaluate how predefined candidate cerebral perfusion parameters correlate with collateral circulation status and to assess their capacity to predict infarct growth in patients with acute ischemic stroke (AIS) eligible for endovascular therapy. Patients enrolled in the SWIFT PRIME trial with baseline computed tomography perfusion (CTP) scans were included. RAPID software was used to calculate mean relative cerebral blood volume (rCBV) in hypoperfused regions, and hypoperfusion index ratio (HIR). Blind assessments of collaterals were performed using CT angiography in the whole sample and cerebral angiogram in the endovascular group. Reperfusion was assessed on 27-h CTP; infarct volume was assessed on 27-h magnetic resonance imaging/CT scans. Logistic and rank linear regression models were conducted. We included 158 patients. High rCBV ( p = 0.03) and low HIR ( p = 0.03) were associated with good collaterals. A positive association was found between rCBV and better collateral grades on cerebral angiography ( p = 0.01). Baseline and 27-h follow-up CTP were available for 115 patients, of whom 74 (64%) achieved successful reperfusion. Lower rCBV predicted a higher infarct growth in successfully reperfused patients ( p = 0.038) and in the endovascular treatment group ( p = 0.049). Finally, rCBV and HIR may serve as markers of collateral circulation in AIS patients prior to endovascular therapy. Unique identifier: NCT0165746.

Three-dimensional reconstruction of vessels with stenoses and aneurysms from dual biplane angiograms

NASA Astrophysics Data System (ADS)

Fessler, Jeffrey A.; Macovski, Albert

1989-05-01

Parametric model-based approaches to 3-D reconstruction of vessels overcome the inherent problem of underdeterminancy in reconstruction from limited views by incorporating a priori knowledge about the structure of vessels and about the measurement statistics. In this paper, we describe two extensions to the parametric approach. First, we consider the problem of reconstruction from a pair of bi-plane angiograms that are acquired at different projection angles. Since bi-plane angiography systems are widely available, this is a practical measurement geometry. The patient may move between acquisitions, so we have extended our model to allow for object translation between the first and second pair of projections. Second, we describe how to accurately estimate the dimensions of a aneurysm from the dual-biplane angiogram. We applied the new algorithm to four synthetic angiograms (projection angles 0°, 20°, 90°, and 110°) of a vessel with a small aneurysm and an eccentric stenosis. The angiograms were corrupted by additive noise and background structure. Except near the top and bottom of the aneurysm, the estimated cross sections of the aneurysm and stenosis agree very well with the true cross sections.

Computed Tomography

NASA Astrophysics Data System (ADS)

Castellano, Isabel; Geleijns, Jacob

After its clinical introduction in 1973, computed tomography developed from an x-ray modality for axial imaging in neuroradiology into a versatile three dimensional imaging modality for a wide range of applications in for example oncology, vascular radiology, cardiology, traumatology and even in interventional radiology. Computed tomography is applied for diagnosis, follow-up studies and screening of healthy subpopulations with specific risk factors. This chapter provides a general introduction in computed tomography, covering a short history of computed tomography, technology, image quality, dosimetry, room shielding, quality control and quality criteria.

Do C-reactive protein level, white blood cell count, and pain location guide the selection of patients for computed tomography imaging in non-traumatic acute abdomen?

PubMed

Ozan, E; Atac, G K; Evrin, T; Alisar, K; Sonmez, L O; Alhan, A

2017-02-01

The value of abdominal computed tomography in non-traumatic abdominal pain has been well established. On the other hand, to manage computed tomography, appropriateness has become more of an issue as a result of the concomitant increase in patient radiation exposure with increased computed tomography use. The purpose of this study was to investigate whether C-reactive protein, white blood cell count, and pain location may guide the selection of patients for computed tomography in non-traumatic acute abdomen. Patients presenting with acute abdomen to the emergency department over a 12-month period and who subsequently underwent computed tomography were retrospectively reviewed. Those with serum C-reactive protein and white blood cell count measured on admission or within 24 h of the computed tomography were selected. Computed tomography examinations were retrospectively reviewed, and final diagnoses were designated either positive or negative for pathology relating to presentation with acute abdomen. White blood cell counts, C-reactive protein levels, and pain locations were analyzed to determine whether they increased or decreased the likelihood of producing a diagnostic computed tomography. The likelihood ratio for computed tomography positivity with a C-reactive protein level above 5 mg/L was 1.71, while this increased to 7.71 in patients with combined elevated C-reactive protein level and white blood cell count and right lower quadrant pain. Combined elevated C-reactive protein level and white blood cell count in patients with right lower quadrant pain may represent a potential factor that could guide the decision to perform computed tomography in non-traumatic acute abdomen.

Preoperative N Staging of Gastric Cancer by Stomach Protocol Computed Tomography

PubMed Central

Kim, Se Hoon; Kim, Jeong Jae; Lee, Jeong Sub; Kim, Seung Hyoung; Kim, Bong Soo; Maeng, Young Hee; Hyun, Chang Lim; Kim, Min Jeong

2013-01-01

Purpose Clinical stage of gastric cancer is currently assessed by computed tomography. Accurate clinical staging is important for the tailoring of therapy. This study evaluated the accuracy of clinical N staging using stomach protocol computed tomography. Materials and Methods Between March 2004 and November 2012, 171 patients with gastric cancer underwent preoperative stomach protocol computed tomography (Jeju National University Hospital; Jeju, Korea). Their demographic and clinical characteristics were reviewed retrospectively. Two radiologists evaluated cN staging using axial and coronal computed tomography images, and cN stage was matched with pathologic results. The diagnostic accuracy of stomach protocol computed tomography for clinical N staging and clinical characteristics associated with diagnostic accuracy were evaluated. Results The overall accuracy of stomach protocol computed tomography for cN staging was 63.2%. Computed tomography images of slice thickness 3.0 mm had a sensitivity of 60.0%; a specificity of 89.6%; an accuracy of 78.4%; and a positive predictive value of 78.0% in detecting lymph node metastases. Underestimation of cN stage was associated with larger tumor size (P<0.001), undifferentiated type (P=0.003), diffuse type (P=0.020), more advanced pathologic stage (P<0.001), and larger numbers of harvested and metastatic lymph nodes (P<0.001 each). Tumor differentiation was an independent factor affecting underestimation by computed tomography (P=0.045). Conclusions Computed tomography with a size criterion of 8 mm is highly specific but relatively insensitive in detecting nodal metastases. Physicians should keep in mind that computed tomography may not be an appropriate tool to detect nodal metastases for choosing appropriate treatment. PMID:24156034

Three-dimensional automated choroidal volume assessment on standard spectral-domain optical coherence tomography and correlation with the level of diabetic macular edema.

PubMed

Gerendas, Bianca S; Waldstein, Sebastian M; Simader, Christian; Deak, Gabor; Hajnajeeb, Bilal; Zhang, Li; Bogunovic, Hrvoje; Abramoff, Michael D; Kundi, Michael; Sonka, Milan; Schmidt-Erfurth, Ursula

2014-11-01

To measure choroidal thickness on spectral-domain optical coherence tomography (SD OCT) images using automated algorithms and to correlate choroidal pathology with retinal changes attributable to diabetic macular edema (DME). Post hoc analysis of multicenter clinical trial baseline data. SD OCT raster scans/fluorescein angiograms were obtained from 284 treatment-naïve eyes of 142 patients with clinically significant DME and from 20 controls. Three-dimensional (3D) SD OCT images were evaluated by a certified independent reading center analyzing retinal changes associated with diabetic retinopathy. Choroidal thicknesses were analyzed using a fully automated algorithm. Angiograms were assessed manually. Multiple endpoint correction according to Bonferroni-Holm was applied. Main outcome measures were average retinal/choroidal thickness on fovea-centered or peak of edema (thickest point of edema)-centered Early Treatment Diabetic Retinopathy Study grid, maximum area of leakage, and the correlation between retinal and choroidal thicknesses. Total choroidal thickness is significantly reduced in DME (175 ± 23 μm; P = .0016) and nonedematous fellow eyes (177 ± 20 μm; P = .009) of patients compared with healthy control eyes (190 ± 23 μm). Retinal/choroidal thickness values showed no significant correlation (1-mm: P = .27, r(2) = 0.01; 3-mm: P = .96, r(2) < 0.0001; 6-mm: P = .42, r(2) = 0.006). No significant difference was found in the 1- or 3-mm circle of a retinal peak of edema-centered grid. All other measurements of choroidal/retinal thickness (DME vs healthy, DME vs peak of edema-centered, DME vs fellow, healthy vs fellow, peak of edema-centered vs healthy, peak of edema-centered vs fellow eyes) were compared but no statistically significant correlation was found. By tendency a thinner choroid correlates with larger retinal leakage areas. Automated algorithms can be used to reliably assess choroidal thickness in eyes with DME. Choroidal thickness was generally reduced in patients with diabetes if DME is present in 1 eye; however, no correlation was found between choroidal/retinal pathologies, suggesting different pathogenetic pathways. Copyright © 2014 Elsevier Inc. All rights reserved.

Computer quantitation of coronary angiograms

NASA Technical Reports Server (NTRS)

Ledbetter, D. C.; Selzer, R. H.; Gordon, R. M.; Blankenhorn, D. H.; Sanmarco, M. E.

1978-01-01

A computer technique is being developed at the Jet Propulsion Laboratory to automate the measurement of coronary stenosis. A Vanguard 35mm film transport is optically coupled to a Spatial Data System vidicon/digitizer which in turn is controlled by a DEC PDP 11/55 computer. Programs have been developed to track the edges of the arterial shadow, to locate normal and atherosclerotic vessel sections and to measure percent stenosis. Multiple frame analysis techniques are being investigated that involve on the one hand, averaging stenosis measurements from adjacent frames, and on the other hand, averaging adjacent frame images directly and then measuring stenosis from the averaged image. For the latter case, geometric transformations are used to force registration of vessel images whose spatial orientation changes.

Diagnostic contribution of cardiac magnetic resonance in patients with acute coronary syndrome and culprit-free angiograms.

PubMed

Kawecki, Damian; Morawiec, Beata; Monney, Pierre; Pellaton, Cyril; Wojciechowska, Celina; Jojko, Joanna; Basiak, Marcin; Przywara-Chowaniec, Brygida; Fournier, Stephane; Nowalany-Kozielska, Ewa; Schwitter, Juerg; Muller, Olivier

2015-01-14

In spite of robust knowledge about underlying ischemic myocardial damage, acute coronary syndromes (ACS) with culprit-free angiograms raise diagnostic concerns. The present study aimed to evaluate the additional value of cardiac magnetic resonance (CMR) over commonly available non-CMR standard tests, for the differentiation of myocardial injury in patients with ACS and non-obstructed coronary arteries. Patients with ACS, elevated hs-TnT, and a culprit-free angiogram were prospectively enrolled into the study between January 2009 and July 2013. After initial evaluation with standard tests (ECG, echocardiography, hs-TnT) and provisional exclusion of acute myocardial infarction (AMI) in coronary angiogram, patients were referred for CMR with the suspicion of myocarditis or Takotsubo cardiomyopathy (TTC). According to the result of CMR, patients were reclassified as having myocarditis, AMI, TTC, or non-injured myocardium as assessed by late gadolinium enhancement. Out of 5110 patients admitted with ACS, 75 had normal coronary angiograms and entered the study; 69 of them (92%) were suspected for myocarditis and 6 (8%) for TTC. After CMR, 49 patients were finally diagnosed with myocarditis (65%), 3 with TTC (4%), 7 with AMI (9%), and 16 (21%) with non-injured myocardium. The provisional diagnosis was changed or excluded in 23 patients (31%), with a 9% rate of unrecognized AMI. The study results suggest that the evaluation of patients with ACS and culprit-free angiogram should be complemented by a CMR examination, if available, because the initial work-up with non-CMR tests leads to a significant proportion of misdiagnosed AMI.

Complex differential variance angiography with noise-bias correction for optical coherence tomography of the retina

PubMed Central

Braaf, Boy; Donner, Sabine; Nam, Ahhyun S.; Bouma, Brett E.; Vakoc, Benjamin J.

2018-01-01

Complex differential variance (CDV) provides phase-sensitive angiographic imaging for optical coherence tomography (OCT) with immunity to phase-instabilities of the imaging system and small-scale axial bulk motion. However, like all angiographic methods, measurement noise can result in erroneous indications of blood flow that confuse the interpretation of angiographic images. In this paper, a modified CDV algorithm that corrects for this noise-bias is presented. This is achieved by normalizing the CDV signal by analytically derived upper and lower limits. The noise-bias corrected CDV algorithm was implemented into an experimental 1 μm wavelength OCT system for retinal imaging that used an eye tracking scanner laser ophthalmoscope at 815 nm for compensation of lateral eye motions. The noise-bias correction improved the CDV imaging of the blood flow in tissue layers with a low signal-to-noise ratio and suppressed false indications of blood flow outside the tissue. In addition, the CDV signal normalization suppressed noise induced by galvanometer scanning errors and small-scale lateral motion. High quality cross-section and motion-corrected en face angiograms of the retina and choroid are presented. PMID:29552388

Complex differential variance angiography with noise-bias correction for optical coherence tomography of the retina.

PubMed

Braaf, Boy; Donner, Sabine; Nam, Ahhyun S; Bouma, Brett E; Vakoc, Benjamin J

2018-02-01

Complex differential variance (CDV) provides phase-sensitive angiographic imaging for optical coherence tomography (OCT) with immunity to phase-instabilities of the imaging system and small-scale axial bulk motion. However, like all angiographic methods, measurement noise can result in erroneous indications of blood flow that confuse the interpretation of angiographic images. In this paper, a modified CDV algorithm that corrects for this noise-bias is presented. This is achieved by normalizing the CDV signal by analytically derived upper and lower limits. The noise-bias corrected CDV algorithm was implemented into an experimental 1 μm wavelength OCT system for retinal imaging that used an eye tracking scanner laser ophthalmoscope at 815 nm for compensation of lateral eye motions. The noise-bias correction improved the CDV imaging of the blood flow in tissue layers with a low signal-to-noise ratio and suppressed false indications of blood flow outside the tissue. In addition, the CDV signal normalization suppressed noise induced by galvanometer scanning errors and small-scale lateral motion. High quality cross-section and motion-corrected en face angiograms of the retina and choroid are presented.

Clinical characteristics of occult macular dystrophy in family with mutation of RP1l1 gene.

PubMed

Tsunoda, Kazushige; Usui, Tomoaki; Hatase, Tetsuhisa; Yamai, Satoshi; Fujinami, Kaoru; Hanazono, Gen; Shinoda, Kei; Ohde, Hisao; Akahori, Masakazu; Iwata, Takeshi; Miyake, Yozo

2012-06-01

To report the clinical characteristics of occult macular dystrophy (OMD) in members of one family with a mutation of the RP1L1 gene. Fourteen members with a p.Arg45Trp mutation in the RP1L1 gene were examined. The visual acuity, visual fields, fundus photographs, fluorescein angiograms, full-field electroretinograms, multifocal electroretinograms, and optical coherence tomographic images were examined. The clinical symptoms and signs and course of the disease were documented. All the members with the RP1L1 mutation except one woman had ocular symptoms and signs of OMD. The fundus was normal in all the patients during the entire follow-up period except in one patient with diabetic retinopathy. Optical coherence tomography detected the early morphologic abnormalities both in the photoreceptor inner/outer segment line and cone outer segment tip line. However, the multifocal electroretinograms were more reliable in detecting minimal macular dysfunction at an early stage of OMD. The abnormalities in the multifocal electroretinograms and optical coherence tomography observed in the OMD patients of different durations strongly support the contribution of RP1L1 mutation to the presence of this disease.

Computed tomography vs. digital radiography assessment for detection of osteolysis in asymptomatic patients with uncemented cups: a proposal for a new classification system based on computer tomography.

PubMed

Sandgren, Buster; Crafoord, Joakim; Garellick, Göran; Carlsson, Lars; Weidenhielm, Lars; Olivecrona, Henrik

2013-10-01

Digital radiographic images in the anterior-posterior and lateral view have been gold standard for evaluation of peri-acetabular osteolysis for patients with an uncemented hip replacement. We compared digital radiographic images and computer tomography in detection of peri-acetabular osteolysis and devised a classification system based on computer tomography. Digital radiographs were compared with computer tomography on 206 hips, with a mean follow up 10 years after surgery. The patients had no clinical signs of osteolysis and none were planned for revision surgery. On digital radiographs, 192 cases had no osteolysis and only 14 cases had osteolysis. When using computer tomography there were 184 cases showing small or large osteolysis and only 22 patients had no osteolysis. A classification system for peri-acetabular osteolysis is proposed based on computer tomography that is easy to use on standard follow up evaluation. Copyright © 2013 Elsevier Inc. All rights reserved.

Ultrahigh-speed non-invasive widefield angiography

NASA Astrophysics Data System (ADS)

Blatter, Cedric; Klein, Thomas; Grajciar, Branislav; Schmoll, Tilman; Wieser, Wolfgang; Andre, Raphael; Huber, Robert; Leitgeb, Rainer A.

2012-07-01

Retinal and choroidal vascular imaging is an important diagnostic benefit for ocular diseases such as age-related macular degeneration. The current gold standard for vessel visualization is fluorescence angiography. We present a potential non-invasive alternative to image blood vessels based on functional Fourier domain optical coherence tomography (OCT). For OCT to compete with the field of view and resolution of angiography while maintaining motion artifacts to a minimum, ultrahigh-speed imaging has to be introduced. We employ Fourier domain mode locking swept source technology that offers high quality imaging at an A-scan rate of up to 1.68 MHz. We present retinal angiogram over ˜48 deg acquired in a few seconds in a single recording without the need of image stitching. OCT at 1060 nm allows for high penetration in the choroid and efficient separate characterization of the retinal and choroidal vascularization.

Assessment of the Role of Different Imaging Modalities with Emphasis on Fdg Pet/Ct in the Management of Well Differentiated Thyroid Cancer (WDTC).

PubMed

Kendi A, Tuba Karagulle; Mudalegundi, Shwetha; Switchenko, Jeffrey; Lee, Daniel; Halkar, Raghuveer; Chen, Amy Y

2016-01-01

Positron emission tomography/computed tomography is suggested to have a role in detection of iodine negative recurrence in well differentiated thyroid cancer. The aim of this study is to identify role of different imaging modalities in the management of well differentiated thyroid cancer. We reviewed 900 well differentiated thyroid cancer patients after post-thyroidectomy who underwent recombinant human thyroid stimulating hormone stimulated Sodium Iodide I 131 imaging. Out of 900 patients, 74 had positron emission tomography/computed tomography. Multivariate analysis was performed by controlling positron emission tomography/computed tomography, Sodium Iodide I 131 scan, neck ultrasonography, age, sex, primary tumor size, stage, histology, thyroglobulin. Patients were grouped according to results of Sodium Iodide I 131 scan and positron emission tomography/computed tomography. Positron emission tomography/computed tomography was positive in 23 of 74 patients. The sensitivity for positron emission tomography was 11/11(100%), the specificity was 51/63 (81.0%), the positive predictive value was 11/23 (47.8%), and the negative predictive value was 51/51 (100%). The sensitivity for the neck ultrasonography was 4/8 (50%), the specificity was 53/60 (88.3%), positive predictive value was 4/11 (36.4%), and negative predictive value was 53/57 (93.0%). 50% of patients who had Sodium Iodide I 131 negative scan and positive positron emission tomography/computed tomography had a change in management. Thirty-six percent with positive neck ultrasonography had a change in management. Out of 11 recurrences, 6 had distant metastatic disease, and 5/11 had regional nodal disease. Neck ultrasonography showed nodal metastasis in 4/5 (80%). Positron emission tomography/computed tomography altered management in the presence of a high thyroglobulin level and a negative Sodium Iodide I 131 scan. Neck ultrasonography should be the first line of imaging with rising thyroglobulin levels. Positron emission tomography/computed tomography should be considered for cases with high thyroglobulin levels and normal neck ultrasonography to look for distant metastatic disease.

Body CT (CAT Scan)

MedlinePlus

... Resources Professions Site Index A-Z Computed Tomography (CT) - Body Computed tomography (CT) of the body uses ... of CT Scanning of the Body? What is CT Scanning of the Body? Computed tomography, more commonly ...

68Ga/177Lu-labeled DOTA-TATE shows similar imaging and biodistribution in neuroendocrine tumor model.

PubMed

Liu, Fei; Zhu, Hua; Yu, Jiangyuan; Han, Xuedi; Xie, Qinghua; Liu, Teli; Xia, Chuanqin; Li, Nan; Yang, Zhi

2017-06-01

Somatostatin receptors are overexpressed in neuroendocrine tumors, whose endogenous ligands are somatostatin. DOTA-TATE is an analogue of somatostatin, which shows high binding affinity to somatostatin receptors. We aim to evaluate the 68 Ga/ 177 Lu-labeling DOTA-TATE kit in neuroendocrine tumor model for molecular imaging and to try human-positron emission tomography/computed tomography imaging of 68 Ga-DOTA-TATE in neuroendocrine tumor patients. DOTA-TATE kits were formulated and radiolabeled with 68 Ga/ 177 Lu for 68 Ga/ 177 Lu-DOTA-TATE (M-DOTA-TATE). In vitro and in vivo stability of 177 Lu-DOTA-TATE were performed. Nude mice bearing human tumors were injected with 68 Ga-DOTA-TATE or 177 Lu-DOTA-TATE for micro-positron emission tomography and micro-single-photon emission computed tomography/computed tomography imaging separately, and clinical positron emission tomography/computed tomography images of 68 Ga-DOTA-TATE were obtained at 1 h post-intravenous injection from patients with neuroendocrine tumors. Micro-positron emission tomography and micro-single-photon emission computed tomography/computed tomography imaging of 68 Ga-DOTA-TATE and 177 Lu-DOTA-TATE both showed clear tumor uptake which could be blocked by excess DOTA-TATE. In addition, 68 Ga-DOTA-TATE-positron emission tomography/computed tomography imaging in neuroendocrine tumor patients could show primary and metastatic lesions. 68 Ga-DOTA-TATE and 177 Lu-DOTA-TATE could accumulate in tumors in animal models, paving the way for better clinical peptide receptor radionuclide therapy for neuroendocrine tumor patients in Asian population.

Dual-Energy Computed Tomography in Cardiothoracic Vascular Imaging.

PubMed

De Santis, Domenico; Eid, Marwen; De Cecco, Carlo N; Jacobs, Brian E; Albrecht, Moritz H; Varga-Szemes, Akos; Tesche, Christian; Caruso, Damiano; Laghi, Andrea; Schoepf, Uwe Joseph

2018-07-01

Dual energy computed tomography is becoming increasingly widespread in clinical practice. It can expand on the traditional density-based data achievable with single energy computed tomography by adding novel applications to help reach a more accurate diagnosis. The implementation of this technology in cardiothoracic vascular imaging allows for improved image contrast, metal artifact reduction, generation of virtual unenhanced images, virtual calcium subtraction techniques, cardiac and pulmonary perfusion evaluation, and plaque characterization. The improved diagnostic performance afforded by dual energy computed tomography is not associated with an increased radiation dose. This review provides an overview of dual energy computed tomography cardiothoracic vascular applications. Copyright © 2018 Elsevier Inc. All rights reserved.

A Freeware Path to Neutron Computed Tomography

NASA Astrophysics Data System (ADS)

Schillinger, Burkhard; Craft, Aaron E.

Neutron computed tomography has become a routine method at many neutron sources due to the availability of digital detection systems, powerful computers and advanced software. The commercial packages Octopus by Inside Matters and VGStudio by Volume Graphics have been established as a quasi-standard for high-end computed tomography. However, these packages require a stiff investment and are available to the users only on-site at the imaging facility to do their data processing. There is a demand from users to have image processing software at home to do further data processing; in addition, neutron computed tomography is now being introduced even at smaller and older reactors. Operators need to show a first working tomography setup before they can obtain a budget to build an advanced tomography system. Several packages are available on the web for free; however, these have been developed for X-rays or synchrotron radiation and are not immediately useable for neutron computed tomography. Three reconstruction packages and three 3D-viewers have been identified and used even for Gigabyte datasets. This paper is not a scientific publication in the classic sense, but is intended as a review to provide searchable help to make the described packages usable for the tomography community. It presents the necessary additional preprocessing in ImageJ, some workarounds for bugs in the software, and undocumented or badly documented parameters that need to be adapted for neutron computed tomography. The result is a slightly complicated, but surprisingly high-quality path to neutron computed tomography images in 3D, but not a replacement for the even more powerful commercial software mentioned above.

Terahertz Computed Tomography of NASA Thermal Protection System Materials

NASA Technical Reports Server (NTRS)

Roth, D. J.; Reyes-Rodriguez, S.; Zimdars, D. A.; Rauser, R. W.; Ussery, W. W.

2011-01-01

A terahertz axial computed tomography system has been developed that uses time domain measurements in order to form cross-sectional image slices and three-dimensional volume renderings of terahertz-transparent materials. The system can inspect samples as large as 0.0283 cubic meters (1 cubic foot) with no safety concerns as for x-ray computed tomography. In this study, the system is evaluated for its ability to detect and characterize flat bottom holes, drilled holes, and embedded voids in foam materials utilized as thermal protection on the external fuel tanks for the Space Shuttle. X-ray micro-computed tomography was also performed on the samples to compare against the terahertz computed tomography results and better define embedded voids. Limits of detectability based on depth and size for the samples used in this study are loosely defined. Image sharpness and morphology characterization ability for terahertz computed tomography are qualitatively described.

Retrospective multi-phase non-contrast-enhanced magnetic resonance angiography (ROMANCE MRA) for robust angiogram separation in the presence of cardiac arrhythmia.

PubMed

Kim, Hahnsung; Park, Suhyung; Kim, Eung Yeop; Park, Jaeseok

2018-09-01

To develop a novel, retrospective multi-phase non-contrast-enhanced MRA (ROMANCE MRA) in a single acquisition for robust angiogram separation even in the presence of cardiac arrhythmia. In the proposed ROMANCE MRA, data were continuously acquired over all cardiac phases using retrospective, multi-phase flow-sensitive single-slab 3D fast spin echo (FSE) with variable refocusing flip angles, while an external pulse oximeter was in sync with pulse repetitions in FSE to record real-time information on cardiac cycles. Data were then sorted into k-bin space using the real-time cardiac information. Angiograms were reconstructed directly from k-bin space by solving a constrained optimization problem with both subtraction-induced sparsity and low rank priors. Peripheral MRA was performed in normal volunteers with/without caffeine consumption and a volunteer with cardiac arrhythmia using conventional fresh blood imaging (FBI) and the proposed ROMANCE MRA for comparison. The proposed ROMANCE MRA shows superior performance in accurately delineating both major and small vessel branches with robust background suppression if compared with conventional FBI. Even in the presence of irregular heartbeats, the proposed method exhibits clear depiction of angiograms over conventional methods within clinically reasonable imaging time. We successfully demonstrated the feasibility of the proposed ROMANCE MRA in generating robust angiograms with background suppression. © 2018 International Society for Magnetic Resonance in Medicine.

Comparison of magnetic resonance imaging and computed tomography in suspected lesions in the posterior cranial fossa.

PubMed Central

Teasdale, G. M.; Hadley, D. M.; Lawrence, A.; Bone, I.; Burton, H.; Grant, R.; Condon, B.; Macpherson, P.; Rowan, J.

1989-01-01

OBJECTIVE--To compare computed tomography and magnetic resonance imaging in investigating patients suspected of having a lesion in the posterior cranial fossa. DESIGN--Randomised allocation of newly referred patients to undergo either computed tomography or magnetic resonance imaging; the alternative investigation was performed subsequently only in response to a request from the referring doctor. SETTING--A regional neuroscience centre serving 2.7 million. PATIENTS--1020 Patients recruited between April 1986 and December 1987, all suspected by neurologists, neurosurgeons, or other specialists of having a lesion in the posterior fossa and referred for neuroradiology. The groups allocated to undergo computed tomography or magnetic resonance imaging were well matched in distributions of age, sex, specialty of referring doctor, investigation as an inpatient or an outpatient, suspected site of lesion, and presumed disease process; the referring doctor's confidence in the initial clinical diagnosis was also similar. INTERVENTIONS--After the patients had been imaged by either computed tomography or magnetic resonance (using a resistive magnet of 0.15 T) doctors were given the radiologist's report and a form asking if they considered that imaging with the alternative technique was necessary and, if so, why; it also asked for their current diagnoses and their confidence in them. MAIN OUTCOME MEASURES--Number of requests for the alternative method of investigation. Assessment of characteristics of patients for whom further imaging was requested and lesions that were suspected initially and how the results of the second imaging affected clinicians' and radiologists' opinions. RESULTS--Ninety three of the 501 patients who initially underwent computed tomography were referred subsequently for magnetic resonance imaging whereas only 28 of the 493 patients who initially underwent magnetic resonance imaging were referred subsequently for computed tomography. Over the study the number of patients referred for magnetic resonance imaging after computed tomography increased but requests for computed tomography after magnetic resonance imaging decreased. The reason that clinicians gave most commonly for requesting further imaging by magnetic resonance was that the results of the initial computed tomography failed to exclude their suspected diagnosis (64 patients). This was less common in patients investigated initially by magnetic resonance imaging (eight patients). Management of 28 patients (6%) imaged initially with computed tomography and 12 patients (2%) imaged initially with magnetic resonance was changed on the basis of the results of the alternative imaging. CONCLUSIONS--Magnetic resonance imaging provided doctors with the information required to manage patients suspected of having a lesion in the posterior fossa more commonly than computed tomography, but computed tomography alone was satisfactory in 80% of cases... PMID:2506965

Congruence Between Pulmonary Function and Computed Tomography Imaging Assessment of Cystic Fibrosis Severity.

PubMed

Rybacka, Anna; Goździk-Spychalska, Joanna; Rybacki, Adam; Piorunek, Tomasz; Batura-Gabryel, Halina; Karmelita-Katulska, Katarzyna

2018-05-04

In cystic fibrosis, pulmonary function tests (PFTs) and computed tomography are used to assess lung function and structure, respectively. Although both techniques of assessment are congruent there are lingering doubts about which PFTs variables show the best congruence with computed tomography scoring. In this study we addressed the issue by reinvestigating the association between PFTs variables and the score of changes seen in computed tomography scans in patients with cystic fibrosis with and without pulmonary exacerbation. This retrospective study comprised 40 patients in whom PFTs and computed tomography were performed no longer than 3 weeks apart. Images (inspiratory: 0.625 mm slice thickness, 0.625 mm interval; expiratory: 1.250 mm slice thickness, 10 mm interval) were evaluated with the Bhalla scoring system. The most frequent structural abnormality found in scans were bronchiectases and peribronchial thickening. The strongest relationship was found between the Bhalla sore and forced expiratory volume in 1 s (FEV1). The Bhalla sore also was related to forced vital capacity (FVC), FEV1/FVC ratio, residual volume (RV), and RV/total lung capacity (TLC) ratio. We conclude that lung structural data obtained from the computed tomography examination are highly congruent to lung function data. Thus, computed tomography imaging may supersede functional assessment in cases of poor compliance with spirometry procedures in the lederly or children. Computed tomography also seems more sensitive than PFTs in the assessment of cystic fibrosis progression. Moreover, in early phases of cystic fibrosis, computed tomography, due to its excellent resolution, may be irreplaceable in monitoring pulmonary damage.

SCCT guidelines for the performance and acquisition of coronary computed tomographic angiography: A report of the society of Cardiovascular Computed Tomography Guidelines Committee: Endorsed by the North American Society for Cardiovascular Imaging (NASCI).

PubMed

Abbara, Suhny; Blanke, Philipp; Maroules, Christopher D; Cheezum, Michael; Choi, Andrew D; Han, B Kelly; Marwan, Mohamed; Naoum, Chris; Norgaard, Bjarne L; Rubinshtein, Ronen; Schoenhagen, Paul; Villines, Todd; Leipsic, Jonathon

In response to recent technological advancements in acquisition techniques as well as a growing body of evidence regarding the optimal performance of coronary computed tomography angiography (coronary CTA), the Society of Cardiovascular Computed Tomography Guidelines Committee has produced this update to its previously established 2009 "Guidelines for the Performance of Coronary CTA" (1). The purpose of this document is to provide standards meant to ensure reliable practice methods and quality outcomes based on the best available data in order to improve the diagnostic care of patients. Society of Cardiovascular Computed Tomography Guidelines for the Interpretation is published separately (2). The Society of Cardiovascular Computed Tomography Guidelines Committee ensures compliance with all existing standards for the declaration of conflict of interest by all authors and reviewers for the purpose ofclarity and transparency. Copyright © 2016 Society of Cardiovascular Computed Tomography. All rights reserved.

Application of multidetector-row computed tomography in propeller flap planning.

PubMed

Ono, Shimpei; Chung, Kevin C; Hayashi, Hiromitsu; Ogawa, Rei; Takami, Yoshihiro; Hyakusoku, Hiko

2011-02-01

The propeller flap is defined as (1) being island-shaped, (2) having an axis that includes the perforators, and (3) having the ability to be rotated around an axis. The advantage of the propeller flap is that it is a pedicle flap that can be applied to cover defects located at the distal ends of the extremities. The specific aims of the authors' study were (1) to evaluate the usefulness of multidetector-row computed tomography in the planning of propeller flaps and (2) to present a clinical case series of propeller flap reconstructions that were planned preoperatively using multidetector-row computed tomography. The authors retrospectively analyzed all cases between April of 2007 and April of 2010 at Nippon Medical School Hospital in Tokyo, where multidetector-row computed tomography was used preoperatively to plan surgical reconstructions using propeller flaps. Thirteen patients underwent 16 flaps using the propeller flap technique. The perforators were identified accurately by multidetector-row computed tomography preoperatively in all cases. This is the first report describing the application of multidetector-row computed tomography in the planning of propeller flaps. Multidetector-row computed tomography is superior to other imaging methods because it demonstrates more precisely the perforator's position and subcutaneous course using high-resolution three-dimensional images. By using multidetector-row computed tomography to preoperatively identify a flap's perforators, the surgeon can better plan the flap design to efficiently conduct the flap surgery.

Comparison of computed tomography and magnetic resonance imaging for the evaluation of canine intranasal neoplasia.

PubMed

Drees, R; Forrest, L J; Chappell, R

2009-07-01

Canine intranasal neoplasia is commonly evaluated using computed tomography to indicate the diagnosis, to determine disease extent, to guide histological sampling location and to plan treatment. With the expanding use of magnetic resonance imaging in veterinary medicine, this modality has been recently applied for the same purpose. The aim of this study was to compare the features of canine intranasal neoplasia using computed tomography and magnetic resonance imaging. Twenty-one dogs with confirmed intranasal neoplasia underwent both computed tomography and magnetic resonance imaging. The images were reviewed retrospectively for the bony and soft tissue features of intranasal neoplasia. Overall computed tomography and magnetic resonance imaging performed very similarly. However, lysis of bones bordering the nasal cavity and mucosal thickening was found on computed tomography images more often than on magnetic resonance images. Small amounts of fluid in the nasal cavity were more often seen on magnetic resonance images. However, fluid in the frontal sinuses was seen equally well with both modalities. We conclude that computed tomography is satisfactory for evaluation of canine intranasal neoplasia, and no clinically relevant benefit is gained using magnetic resonance imaging for intranasal neoplasia without extent into the cranial cavity.

F-18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Appearance of Extramedullary Hematopoesis in a Case of Primary Myelofibrosis

PubMed Central

Mukherjee, Anirban; Bal, Chandrasekhar; Tripathi, Madhavi; Das, Chandan Jyoti; Shamim, Shamim Ahmed

2017-01-01

A 44-year-old female with known primary myelofibrosis presented with shortness of breath. High Resolution Computed Tomography thorax revealed large heterogeneously enhancing extraparenchymal soft tissue density mass involving bilateral lung fields. F-18-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography revealed mildly FDG avid soft tissue density mass with specks of calcification involving bilateral lung fields, liver, and spleen. Subsequent histopathologic evaluation from the right lung mass was suggestive of extramedullary hematopoesis. PMID:28533647

Safety of Chemotherapeutic Infusion or Chemoembolization for Hepatocellular Carcinoma Supplied Exclusively by the Cystic Artery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, Beomsik, E-mail: kangbs98@gmail.com; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Chung, Jin Wook, E-mail: chungjw@snu.ac.kr

Purpose: This study was designed to evaluate the safety of chemotherapeutic infusion or chemoembolization by way of the cystic artery in patients with hepatocellular carcinoma (HCC) supplied exclusively by the cystic artery. Methods: Between Jan 2002 and Dec 2011, we performed chemotherapeutic infusion or chemoembolization using iodized oil for the treatment of 27 patients with HCC supplied exclusively by the cystic artery. Computed tomography (CT) scans, digital subtraction angiograms, and medical records were retrospectively reviewed by consensus. Results: The cystic artery originated from the main right hepatic artery in 24 (89 %) patients, from the right anterior hepatic artery inmore » 2 (7 %) patients, and from the left hepatic artery in 1 (4 %) patient. Selective catheterization of the cystic artery was achieved in all patients. Superselection of tumor-feeding vessels from the cystic artery was achieved in 7 patients (26 %). Chemotherapeutic infusion was performed in 18 patients (67 %), and chemoembolization was performed in 9 patients (33 %). There were no major complications and only 2 minor complications, including vasovagal syncope and nausea with vomiting. Individual tumor response supplied exclusively by the cystic artery at the follow-up enhanced CT scan were complete response (n = 16), partial response (n = 3), and stable disease (n = 8). Conclusion: HCC supplied exclusively by the cystic artery can be safely treated without severe complications by chemotherapeutic infusion or chemoembolization using iodized oil through the cystic artery.« less

Cone beam computed tomography in the diagnosis of dental disease.

PubMed

Tetradis, Sotirios; Anstey, Paul; Graff-Radford, Steven

2011-07-01

Conventional radiographs provide important information for dental disease diagnosis. However, they represent 2-D images of 3-D objects with significant structure superimposition and unpredictable magnification. Cone beam computed tomography, however, allows true 3-D visualization of the dentoalveolar structures, avoiding major limitations of conventional radiographs. Cone beam computed tomography images offer great advantages in disease detection for selected patients. The authors discuss cone beam computed tomography applications in dental disease diagnosis, reviewing the pertinent literature when available.

Patient satisfaction with the consent discussion is not improved by showing patients their computed tomography or angiography images before they undergo vascular surgery.

PubMed

LeBlanc, Dominic; Power, Adam H; DeRose, Guy; Duncan, Audra; Dubois, Luc

2018-05-18

Patient-based decision aids and other multimedia tools have been developed to help enrich the preoperative discussion between surgeon and patient. Use of these tools, however, can be time-consuming and logistically challenging. We investigated whether simply showing patients their images from preoperative computed tomography (CT) or angiography would improve patients' satisfaction with the preoperative discussion. We also examined whether this improved the patient's understanding and trust and whether it contributed to increased preoperative anxiety. Patients undergoing either elective abdominal aortic aneurysm repair or lower limb revascularization were randomly assigned to either standard perioperative discussion or perioperative discussion and review of images (CT image or angiogram). Randomization was concealed and stratified by surgeon. Primary outcome was patient satisfaction with the preoperative discussion as measured by a validated 7-item scale (score, 0-28), with higher scores indicating improved satisfaction. Secondary outcomes included patient understanding, patient anxiety, patient trust, and length of preoperative discussion. Scores were compared using t-test. Overall, 51 patients were randomized, 25 to the intervention arm (discussion and imaging) and 26 to the control arm. Most patients were male (69%), and the average age was 70 years. Forty percent of patients underwent abdominal aortic aneurysm repair, whereas 60% underwent lower limb revascularization. Patient satisfaction with the discussion was generally high, with no added improvement when preoperative images were reviewed (mean score, 24.9 ± 3.02 vs 24.8 ± 2.93; P = .88). Similarly, there was no difference in the patient's anxiety, level of trust, or understanding when the imaging review was compared with standard discussion. There was a trend toward longer preoperative discussions in the group that underwent imaging review (8.18 vs 6.35 minutes; P = .07). Showing patients their CT or angiography images during the preoperative discussion does not improve the patient's satisfaction with the consent discussion. Similarly, there was no effect on the patient's trust, understanding, or anxiety level. Our conclusions are limited by the lack of a standardized measure of patient understanding and not measuring outcomes postoperatively, both of which should be considered in future studies. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Delayed Retroclival and Cervical Spinal Subdural Hematoma Complicated by Preexisting Chiari Malformation in Adult Trauma Patient.

PubMed

Nguyen, Ha Son; Choi, Hoon; Kurpad, Shekar; Soliman, Hesham

2017-09-01

Traumatic spinal subdural hematoma involving the retroclival region and upper cervical spine is a rare pathology. To our knowledge, there have only been 2 prior cases in an adult trauma patient. We describe a patient with preexisting Chiari 1 malformation, who recently sustained a unilateral type 1 occipital condyle fracture with associated disruption of the tectorial membrane and transverse ligament, which returned with a retroclival subdural hematoma extending down to C7, causing spinal cord compression and symptomatic obstructive hydrocephalus. A 30-year-old female sustained a motor vehicle collision. Computed tomography C spine revealed a type I occipital condyle fracture. Magnetic resonance imaging C spine demonstrated disruption of the tectorial membrane and avulsion of the transverse ligament at its attachment to the left C1 tubercle; moreover, there was a Chiari 1 malformation. The patient was neurologically intact. A halo was recommended, but the patient opted for an aspen collar with close management. She was discharged but returned 3 days later with apneic episodes, along with bradycardia and hypertension. She was promptly intubated. Computed tomography head showed interval ventricular enlargement. Magnetic resonance imaging C spine revealed a new ventral hematoma spanning the retroclival region to C7, most pronounced at C2-C3. On examination, she opened her eyes to pain, her pupils were equal and reactive, and she withdrew in all extremities. An external ventricular drain was emergently placed. She underwent a suboccipital craniectomy, C1-3 laminectomies, and occiput-C4 instrumented fusion. The dura was significantly tense, and no epidural hematoma was observed during lateral exploration. Postoperatively, she woke up well, exhibiting a nonfocal neurologic examination. A diagnostic angiogram was negative. She was extubated uneventfully, and the external ventricular drain was weaned off in 4 days. Traumatic spinal subdural hematoma involving both the retroclival region and upper cervical spine can lead to bulbar signs and symptomatic obstructive hydrocephalus. There should be vigilance for this pathology in patients with high-energy craniocervical trauma. Disruption of the tectorial membrane and therapeutic anticoagulation may be risk factors. The clinical scenario can be complicated in the setting of a preexisting Chiari 1 malformation. Copyright © 2017 Elsevier Inc. All rights reserved.

Multiscale tomographic analysis of heterogeneous cast Al-Si-X alloys.

PubMed

Asghar, Z; Requena, G; Sket, F

2015-07-01

The three-dimensional microstructure of cast AlSi12Ni and AlSi10Cu5Ni2 alloys is investigated by laboratory X-ray computed tomography, synchrotron X-ray computed microtomography, light optical tomography and synchrotron X-ray computed microtomography with submicrometre resolution. The results obtained with each technique are correlated with the size of the scanned volumes and resolved microstructural features. Laboratory X-ray computed tomography is sufficient to resolve highly absorbing aluminides but eutectic and primary Si remain unrevealed. Synchrotron X-ray computed microtomography at ID15/ESRF gives better spatial resolution and reveals primary Si in addition to aluminides. Synchrotron X-ray computed microtomography at ID19/ESRF reveals all the phases ≥ ∼1 μm in volumes about 80 times smaller than laboratory X-ray computed tomography. The volumes investigated by light optical tomography and submicrometre synchrotron X-ray computed microtomography are much smaller than laboratory X-ray computed tomography but both techniques provide local chemical information on the types of aluminides. The complementary techniques applied enable a full three-dimensional characterization of the microstructure of the alloys at length scales ranging over six orders of magnitude. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

Electromagnetic Navigational Bronchoscopy Reduces the Time Required for Localization and Resection of Lung Nodules.

PubMed

Bolton, William David; Cochran, Thomas; Ben-Or, Sharon; Stephenson, James E; Ellis, William; Hale, Allyson L; Binks, Andrew P

The aims of the study were to evaluate electromagnetic navigational bronchoscopy (ENB) and computed tomography-guided placement as localization techniques for minimally invasive resection of small pulmonary nodules and determine whether electromagnetic navigational bronchoscopy is a safer and more effective method than computed tomography-guided localization. We performed a retrospective review of our thoracic surgery database to identify patients who underwent minimally invasive resection for a pulmonary mass and used either electromagnetic navigational bronchoscopy or computed tomography-guided localization techniques between July 2011 and May 2015. Three hundred eighty-three patients had a minimally invasive resection during our study period, 117 of whom underwent electromagnetic navigational bronchoscopy or computed tomography localization (electromagnetic navigational bronchoscopy = 81; computed tomography = 36). There was no significant difference between computed tomography and electromagnetic navigational bronchoscopy patient groups with regard to age, sex, race, pathology, nodule size, or location. Both computed tomography and electromagnetic navigational bronchoscopy were 100% successful at localizing the mass, and there was no difference in the type of definitive surgical resection (wedge, segmentectomy, or lobectomy) (P = 0.320). Postoperative complications occurred in 36% of all patients, but there were no complications related to the localization procedures. In terms of localization time and surgical time, there was no difference between groups. However, the down/wait time between localization and resection was significant (computed tomography = 189 minutes; electromagnetic navigational bronchoscopy = 27 minutes); this explains why the difference in total time (sum of localization, down, and surgery) was significant (P < 0.001). We found electromagnetic navigational bronchoscopy to be as safe and effective as computed tomography-guided wire placement and to provide a significantly decreased down time between localization and surgical resection.

Neurologic improvement without angiographic improvement after antithyroid therapy in a patient with Moyamoya syndrome.

PubMed

Ishigami, Akiko; Toyoda, Kazunori; Suzuki, Rieko; Miyashita, Fumio; Iihara, Koji; Minematsu, Kazuo

2014-01-01

Moyamoya disease with special complications, including Graves' disease, is called as moyamoya syndrome. A 22-year-old Japanese woman had left middle cerebral artery (MCA) territory infarction complicated with Graves' disease. She had right-sided hemiparesis that deteriorated on day 8 with the infarct growth and thyrotoxicosis. On angiogram, the left MCA was occluded at the origin without moyamoya vessels. Positron emission tomography (PET) revealed misery-perfusion phenomenon in the left MCA territory. After initiation of the antithyroid therapy, her hemiparesis became milder. Seventeen months later, her thyroid function was normalized and net-like collateral moyamoya vessels proliferated in the left MCA territory. Misery-perfusion phenomenon persisted on PET. This report is unique in the point of neurologic recovery of the moyamoya patient right after initiation of antithyroid medication without radiological improvement. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Snake spectacle vessel permeability to sodium fluorescein.

PubMed

Bellhorn, Roy W; Strom, Ann R; Motta, Monica J; Doval, John; Hawkins, Michelle G; Paul-Murphy, Joanne

2018-03-01

Assess vascular permeability of the snake spectacle to sodium fluorescein during resting and shedding phases of the ecdysis cycle. Ball python (Python regius). The snake was anesthetized, and spectral domain optic coherence tomography was performed prior to angiographic procedures. An electronically controlled digital single-lens reflex camera with a dual-head flash equipped with filters suitable for fluorescein angiography was used to make images. Sodium fluorescein (10%) solution was administered by intracardiac injection. Angiographic images were made as fluorescein traversed the vasculature of the iris and spectacle. Individually acquired photographic frames were assessed and sequenced into pseudovideo image streams for further evaluation CONCLUSIONS: Fluorescein angiograms of the snake spectacle were readily obtained. Vascular permeability varied with the phase of ecdysis. Copious leakage of fluorescein occurred during the shedding phase. This angiographic method may provide diverse opportunities to investigate vascular aspects of snake spectacle ecdysis, dysecdysis, and the integument in general. © 2017 American College of Veterinary Ophthalmologists.

Role of Angiography in Systemic Lupus Erythematosus-Induced Choroiditis.

PubMed

Lee, Kenneth Rohan; Peng, Lai Yin; Iqbal, Tajunisah Begum; Subrayan, Visvaraja

2017-03-31

To report a case of systemic lupus erythematosus-induced choroidal vasculitis. A 34-year-old woman with a long-standing history of systemic lupus erythematosus had a sudden painless loss of vision in the right eye over 12 hours. Ocular examination revealed a visual acuity of counting fingers of 1 foot on the right eye and 20/20 on the left. There was a relative afferent pupillary defect on the right side with a pink, distinct optic disk margin. Optical coherence tomography of the macula and fundus fluorescein angiogram for the eyes were normal. The MRI brain and orbit with the cerebral MRA did not show signs of optic neuritis or occipital vasculitic changes. However, the indocyanine green angiography revealed patches of ill-defined areas of choroidal hypofluorescence in the early- to mid-phase in the macula region. ICGA becomes the crucial tool in unmasking the presence of choroidal vasculitis.

Sinonasal papilloma: what influences the decision to request a magnetic resonance imaging scan?

PubMed

Kasbekar, A V; Swords, C; Attlmayr, B; Kulkarni, T; Swift, A C

2018-06-18

Computed tomography is the standard pre-operative imaging modality for sinonasal papilloma. The complementary use of magnetic resonance imaging as an additional investigation is debated. This study aimed to establish whether magnetic resonance imaging can accurately detect tumour extent and is a useful adjunct to computed tomography. A retrospective review was conducted on 19 patients with sinonasal papilloma. The interpretation of computed tomography and magnetic resonance imaging scans, by three clinicians, was conducted by comparing prediction of tumour extent. The perceived necessity of magnetic resonance imaging was compared between clinicians. The addition of magnetic resonance imaging improved accuracy of pre-operative interpretation; specifically, this finding was significant in cases with frontal sinus involvement. Surgeons were more likely than a radiologist to request magnetic resonance imaging, particularly when computed tomography indicated frontal sinus disease. Pre-operative combined magnetic resonance imaging and computed tomography helped predict disease in the frontal sinus better than computed tomography alone. A close working relationship between the ENT and radiology departments is important for accurate tumour localisation.

Computer analysis of femoral angiograms for evaluation of atherosclerosis in post-infarct males-clinical correlates

NASA Technical Reports Server (NTRS)

Sanmarco, M. E.; Blankenhorn, D. H.

1975-01-01

Femoral artery atheromatous lesions were studied and their changes as a measure of therapeutic effectiveness were assessed. The incidence of coronary risk factors in 100 patients was determined. Abnormal cholesterol was present in 42 percent, abnormal triglycerides in 66 percent, abnormal intravenous glucose tolerance test in 52 percent, judged from a K value of .9 or less by the technique of Wahlbert. A history of high blood pressure was present in 32 percent. Smoking was one of the most common factors.

Computer tomography of the neurocranium.

PubMed

Liliequist, B; Forssell, A

1976-07-01

The experience with computer tomography of the neurocranium in 300 patients submitted for computer tomography of the brain is reported. The more appropriate projections which may be obtained with the second generation of scanners in combination with an elaborated reconstruction technique seem to constitute a replacement of conventional skull films.

Characterization and morphology of atherosclerotic plaque of coronary arteries: utility of electron-beam tomography to detect non-calcified plaque: a comparison with conventional coronary angiography and intravascular ultrasound.

PubMed

Funabashi, Nobusada; Misumi, Kazuo; Ohnishi, Hiroyuki; Asano, Miki; Komuro, Issei

2007-01-31

Electron-beam tomography (EBT) may provide useful information about characterization and morphology of atherosclerotic plaque of coronary arteries. Twenty-six subjects (20 male, 6 female) with suspected coronary heart disease had two routine (r) and one enhanced (e) EBT scans to detect non-calcified plaque (NCP) in the coronary arterial lumen, and were compared with conventional coronary angiograms (CAG) and intravascular ultrasound (IVUS). Three had the sites, which did not have high CT values suggesting calcification in rEBT, nor which was not enhanced by contrast material in eEBT. One had the site with positive CT values that were supposed to be the proliferation intima or organized thrombus and at the corresponding site mixed plaque was observed in the IVUS image. The other two had the site with negative CT values that were supposed to be fat tissue with significant stenosis in CAG. We also made the cross-sectional images of the vessel and the morphology of the NCP, which projected into the lumen, could be evaluated. We could detect the NCP, differentiate fat tissue from soft tissue and evaluate the morphology of the plaque in EBT.

Study of Image Qualities From 6D Robot-Based CBCT Imaging System of Small Animal Irradiator.

PubMed

Sharma, Sunil; Narayanasamy, Ganesh; Clarkson, Richard; Chao, Ming; Moros, Eduardo G; Zhang, Xin; Yan, Yulong; Boerma, Marjan; Paudel, Nava; Morrill, Steven; Corry, Peter; Griffin, Robert J

2017-01-01

To assess the quality of cone beam computed tomography images obtained by a robotic arm-based and image-guided small animal conformal radiation therapy device. The small animal conformal radiation therapy device is equipped with a 40 to 225 kV X-ray tube mounted on a custom made gantry, a 1024 × 1024 pixels flat panel detector (200 μm resolution), a programmable 6 degrees of freedom robot for cone beam computed tomography imaging and conformal delivery of radiation doses. A series of 2-dimensional radiographic projection images were recorded in cone beam mode by placing and rotating microcomputed tomography phantoms on the "palm' of the robotic arm. Reconstructed images were studied for image quality (spatial resolution, image uniformity, computed tomography number linearity, voxel noise, and artifacts). Geometric accuracy was measured to be 2% corresponding to 0.7 mm accuracy on a Shelley microcomputed tomography QA phantom. Qualitative resolution of reconstructed axial computed tomography slices using the resolution coils was within 200 μm. Quantitative spatial resolution was found to be 3.16 lp/mm. Uniformity of the system was measured within 34 Hounsfield unit on a QRM microcomputed tomography water phantom. Computed tomography numbers measured using the linearity plate were linear with material density ( R 2 > 0.995). Cone beam computed tomography images of the QRM multidisk phantom had minimal artifacts. Results showed that the small animal conformal radiation therapy device is capable of producing high-quality cone beam computed tomography images for precise and conformal small animal dose delivery. With its high-caliber imaging capabilities, the small animal conformal radiation therapy device is a powerful tool for small animal research.

Morphometric analysis - Cone beam computed tomography to predict bone quality and quantity.

PubMed

Hohlweg-Majert, B; Metzger, M C; Kummer, T; Schulze, D

2011-07-01

Modified quantitative computed tomography is a method used to predict bone quality and quantify the bone mass of the jaw. The aim of this study was to determine whether bone quantity or quality was detected by cone beam computed tomography (CBCT) combined with image analysis. MATERIALS AND PROCEDURES: Different measurements recorded on two phantoms (Siemens phantom, Comac phantom) were evaluated on images taken with the Somatom VolumeZoom (Siemens Medical Solutions, Erlangen, Germany) and the NewTom 9000 (NIM s.r.l., Verona, Italy) in order to calculate a calibration curve. The spatial relationships of six sample cylinders and the repositioning from four pig skull halves relative to adjacent defined anatomical structures were assessed by means of three-dimensional visualization software. The calibration curves for computer tomography (CT) and cone beam computer tomography (CBCT) using the Siemens phantom showed linear correlation in both modalities between the Hounsfield Units (HU) and bone morphology. A correction factor for CBCT was calculated. Exact information about the micromorphology of the bone cylinders was only available using of micro computer tomography. Cone-beam computer tomography is a suitable choice for analysing bone mass, but, it does not give any information about bone quality. 2010 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Italian Chapter of the International Society of Cardiovascular Ultrasound expert consensus document on coronary computed tomography angiography: overview and new insights.

PubMed

Sozzi, Fabiola B; Maiello, Maria; Pelliccia, Francesco; Parato, Vito Maurizio; Canetta, Ciro; Savino, Ketty; Lombardi, Federico; Palmiero, Pasquale

2016-09-01

Coronary computed tomography angiography is a noninvasive heart imaging test currently undergoing rapid development and advancement. The high resolution of the three-dimensional pictures of the moving heart and great vessels is performed during a coronary computed tomography to identify coronary artery disease and classify patient risk for atherosclerotic cardiovascular disease. The technique provides useful information about the coronary tree and atherosclerotic plaques beyond simple luminal narrowing and plaque type defined by calcium content. This application will improve image-guided prevention, medical therapy, and coronary interventions. The ability to interpret coronary computed tomography images is of utmost importance as we develop personalized medical care to enable therapeutic interventions stratified on the bases of plaque characteristics. This overview provides available data and expert's recommendations in the utilization of coronary computed tomography findings. We focus on the use of coronary computed tomography to detect coronary artery disease and stratify patients at risk, illustrating the implications of this test on patient management. We describe its diagnostic power in identifying patients at higher risk to develop acute coronary syndrome and its prognostic significance. Finally, we highlight the features of the vulnerable plaques imaged by coronary computed tomography angiography. © 2016, Wiley Periodicals, Inc.

Comparison of computed tomography and magnetic resonance imaging for the evaluation of canine intranasal neoplasia

PubMed Central

Drees, R.; Forrest, L. J.; Chappell, R.

2009-01-01

Objectives Canine intranasal neoplasia is commonly evaluated using computed tomography to indicate the diagnosis, to determine disease extent, to guide histological sampling location and to plan treatment. With the expanding use of magnetic resonance imaging in veterinary medicine, this modality has been recently applied for the same purpose. The aim of this study was to compare the features of canine intranasal neoplasia using computed tomography and magnetic resonance imaging. Methods Twenty-one dogs with confirmed intranasal neoplasia underwent both computed tomography and magnetic resonance imaging. The images were reviewed retrospectively for the bony and soft tissue features of intranasal neoplasia. Results Overall computed tomography and magnetic resonance imaging performed very similarly. However, lysis of bones bordering the nasal cavity and mucosal thickening was found on computed tomography images more often than on magnetic resonance images. Small amounts of fluid in the nasal cavity were more often seen on magnetic resonance images. However, fluid in the frontal sinuses was seen equally well with both modalities. Clinical Significance We conclude that computed tomography is satisfactory for evaluation of canine intranasal neoplasia, and no clinically relevant benefit is gained using magnetic resonance imaging for intranasal neoplasia without extent into the cranial cavity. PMID:19508490

Measurement of Three-dimensional Density Distributions by Holographic Interferometry and Computer Tomography

NASA Technical Reports Server (NTRS)

Vest, C. M.

1982-01-01

The use of holographic interferometry to measure two and threedimensional flows and the interpretation of multiple-view interferograms with computer tomography are discussed. Computational techniques developed for tomography are reviewed. Current research topics are outlined including the development of an automated fringe readout system, optimum reconstruction procedures for when an opaque test model is present in the field, and interferometry and tomography with strongly refracting fields and shocks.

Unique Angiographic Appearances of Moyamoya Disease Detected with 3-Dimensional Rotational Digital Subtraction Angiography Imaging Showing the Hemodynamic Status.

PubMed

Karakama, Jun; Nariai, Tadashi; Hara, Shoko; Hayashi, Shihori; Sumita, Kazutaka; Inaji, Motoki; Tanaka, Yoji; Wagatsuma, Kei; Ishii, Kenji; Nemoto, Shigeru; Maehara, Taketoshi

2018-04-10

The aim of this study was to identify the unique morphological arterial features in patients with moyamoya disease on 3-dimensional rotational digital subtraction angiography. One hundred seven hemispheres of 58 consecutive patients with moyamoya disease that were analyzed with fused 3-dimensional images of internal carotid angiograms and vertebral angiograms that were marked with different colors were reviewed. Angiographic findings in the posterior watershed area were classified, and the utility of the classification was analyzed by comparing it with clinical presentations and quantitative hemodynamic parameters obtained with positron emission tomography. Two unique angiographic appearances were identified. A vacant vessel appearance (no arterial inflow despite absence of cortical infarction) was observed mostly in transient ischemic attack hemispheres. In hemispheres with a vacant vessel appearance, cerebral blood flow was decreased, cerebral blood volume was increased, and mean transit time was prolonged significantly (P = .00017, P = .0061, and P = .00026, respectively). A cocktail vessel appearance (mixture of carotid and vertebral arterial flow) was most commonly observed in asymptomatic cases, as well as in ischemic hemispheres. Cerebral blood volume increased and mean transit time was prolonged significantly (P = .036 and P = .014, respectively) in hemispheres with a cocktail vessel appearance. The trend of progression in hemodynamic severity in the order of normal appearance, cocktail vessel appearance, and vacant vessel appearance in the watershed area was statistically significant. Fused 3-dimensional digital subtraction angiography demonstrated unique angiographic features in the watershed area, and this represented the degree of cerebral hemodynamic impairment in moyamoya disease. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Revascularization decisions in patients with stable angina and intermediate lesions: results of the international survey on interventional strategy.

PubMed

Toth, Gabor G; Toth, Balint; Johnson, Nils P; De Vroey, Frederic; Di Serafino, Luigi; Pyxaras, Stylianos; Rusinaru, Dan; Di Gioia, Giuseppe; Pellicano, Mariano; Barbato, Emanuele; Van Mieghem, Carlos; Heyndrickx, Guy R; De Bruyne, Bernard; Wijns, William

2014-12-01

Fractional flow reserve (FFR) measurement of intermediate coronary stenoses is recommended by guidelines when demonstration of ischemia by noninvasive testing is unavailable. The study aims to evaluate the penetration of this recommendation into current thinking about revascularization strategies for stable coronary artery disease. International Survey on Interventional Strategy was conducted via a web-based platform. First, participants' experiences in interventional cardiology were queried. Second, 5 complete angiograms were provided, presenting only focal intermediate stenoses. FFR and quantitative coronary angiography values were known; however, remained undisclosed. Determination of stenosis significance was asked for each lesion. In cases of uncertainty, the most appropriate adjunctive invasive diagnostic method among quantitative coronary angiography, intravascular ultrasound, optical coherence tomography, or FFR needed to be selected. International Survey on Interventional Strategy was taken by 495 participants who provided 4421 lesion evaluations. In 3158 (71%) decisions, participants relied solely on angiographic appearance that was discordant in 47% with the known FFR, using 0.80 as cutoff value. The use of FFR and imaging modalities was requested in 21% and 8%, respectively. Comparing 4 groups of participants according to the experience in FFR, angiogram-based decisions were less frequent with increasing experience (77% versus 72% versus 69% versus 67%, respectively; P<0.001). As a result, requests for FFR were more frequent (14% versus 19% versus 24% versus 28%, respectively; P<0.001) and rates of discordant decisions decreased (51% versus 49% versus 47% versus 43%, respectively; P<0.022). The findings confirm that, even when all potential external constraints are virtually eliminated, visual estimation continues to dominate the treatment decisions for intermediate stenoses, indicative of a worrisome disconnect between recommendations and current practice. © 2014 American Heart Association, Inc.

Improving early diagnosis of pulmonary infections in patients with febrile neutropenia using low-dose chest computed tomography.

PubMed

Gerritsen, M G; Willemink, M J; Pompe, E; van der Bruggen, T; van Rhenen, A; Lammers, J W J; Wessels, F; Sprengers, R W; de Jong, P A; Minnema, M C

2017-01-01

We performed a prospective study in patients with chemotherapy induced febrile neutropenia to investigate the diagnostic value of low-dose computed tomography compared to standard chest radiography. The aim was to compare both modalities for detection of pulmonary infections and to explore performance of low-dose computed tomography for early detection of invasive fungal disease. The low-dose computed tomography remained blinded during the study. A consensus diagnosis of the fever episode made by an expert panel was used as reference standard. We included 67 consecutive patients on the first day of febrile neutropenia. According to the consensus diagnosis 11 patients (16.4%) had pulmonary infections. Sensitivity, specificity, positive predictive value and negative predictive value were 36%, 93%, 50% and 88% for radiography, and 73%, 91%, 62% and 94% for low-dose computed tomography, respectively. An uncorrected McNemar showed no statistical difference (p = 0.197). Mean radiation dose for low-dose computed tomography was 0.24 mSv. Four out of 5 included patients diagnosed with invasive fungal disease had radiographic abnormalities suspect for invasive fungal disease on the low-dose computed tomography scan made on day 1 of fever, compared to none of the chest radiographs. We conclude that chest radiography has little value in the initial assessment of febrile neutropenia on day 1 for detection of pulmonary abnormalities. Low-dose computed tomography improves detection of pulmonary infiltrates and seems capable of detecting invasive fungal disease at a very early stage with a low radiation dose.

Improving early diagnosis of pulmonary infections in patients with febrile neutropenia using low-dose chest computed tomography

PubMed Central

Pompe, E.; van der Bruggen, T.; van Rhenen, A.; Lammers, J. W. J.; Wessels, F.; Sprengers, R. W.; de Jong, P. A.; Minnema, M. C.

2017-01-01

We performed a prospective study in patients with chemotherapy induced febrile neutropenia to investigate the diagnostic value of low-dose computed tomography compared to standard chest radiography. The aim was to compare both modalities for detection of pulmonary infections and to explore performance of low-dose computed tomography for early detection of invasive fungal disease. The low-dose computed tomography remained blinded during the study. A consensus diagnosis of the fever episode made by an expert panel was used as reference standard. We included 67 consecutive patients on the first day of febrile neutropenia. According to the consensus diagnosis 11 patients (16.4%) had pulmonary infections. Sensitivity, specificity, positive predictive value and negative predictive value were 36%, 93%, 50% and 88% for radiography, and 73%, 91%, 62% and 94% for low-dose computed tomography, respectively. An uncorrected McNemar showed no statistical difference (p = 0.197). Mean radiation dose for low-dose computed tomography was 0.24 mSv. Four out of 5 included patients diagnosed with invasive fungal disease had radiographic abnormalities suspect for invasive fungal disease on the low-dose computed tomography scan made on day 1 of fever, compared to none of the chest radiographs. We conclude that chest radiography has little value in the initial assessment of febrile neutropenia on day 1 for detection of pulmonary abnormalities. Low-dose computed tomography improves detection of pulmonary infiltrates and seems capable of detecting invasive fungal disease at a very early stage with a low radiation dose. PMID:28235014

Nasal computed tomography.

PubMed

Kuehn, Ned F

2006-05-01

Chronic nasal disease is often a challenge to diagnose. Computed tomography greatly enhances the ability to diagnose chronic nasal disease in dogs and cats. Nasal computed tomography provides detailed information regarding the extent of disease, accurate discrimination of neoplastic versus nonneoplastic diseases, and identification of areas of the nose to examine rhinoscopically and suspicious regions to target for biopsy.

Multislice Computed Tomography Accurately Detects Stenosis in Coronary Artery Bypass Conduits

PubMed Central

Duran, Cihan; Sagbas, Ertan; Caynak, Baris; Sanisoglu, Ilhan; Akpinar, Belhhan; Gulbaran, Murat

2007-01-01

The aim of this study was to evaluate the accuracy of multislice computed tomography in detecting graft stenosis or occlusion after coronary artery bypass grafting, using coronary angiography as the standard. From January 2005 through May 2006, 25 patients (19 men and 6 women; mean age, 54 ± 11.3 years) underwent diagnostic investigation of their bypass grafts by multislice computed tomography within 1 month of coronary angiography. The mean time elapsed after coronary artery bypass grafting was 6.2 years. In these 25 patients, we examined 65 bypass conduits (24 arterial and 41 venous) and 171 graft segments (the shaft, proximal anastomosis, and distal anastomosis). Compared with coronary angiography, the segment-based sensitivity, specificity, and positive and negative predictive values of multislice computed tomography in the evaluation of stenosis were 89%, 100%, 100%, and 99%, respectively. The patency rate for multislice compu-ted tomography was 85% (55/65: 3 arterial and 7 venous grafts were occluded), with 100% sensitivity and specificity. From these data, we conclude that multislice computed tomography can accurately evaluate the patency and stenosis of bypass grafts during outpatient follow-up. PMID:17948078

Differences between postmortem computed tomography and conventional autopsy in a stabbing murder case

PubMed Central

Zerbini, Talita; da Silva, Luiz Fernando Ferraz; Ferro, Antonio Carlos Gonçalves; Kay, Fernando Uliana; Junior, Edson Amaro; Pasqualucci, Carlos Augusto Gonçalves; do Nascimento Saldiva, Paulo Hilario

2014-01-01

OBJECTIVE: The aim of the present work is to analyze the differences and similarities between the elements of a conventional autopsy and images obtained from postmortem computed tomography in a case of a homicide stab wound. METHOD: Comparison between the findings of different methods: autopsy and postmortem computed tomography. RESULTS: In some aspects, autopsy is still superior to imaging, especially in relation to external examination and the description of lesion vitality. However, the findings of gas embolism, pneumothorax and pulmonary emphysema and the relationship between the internal path of the instrument of aggression and the entry wound are better demonstrated by postmortem computed tomography. CONCLUSIONS: Although multislice computed tomography has greater accuracy than autopsy, we believe that the conventional autopsy method is fundamental for providing evidence in criminal investigations. PMID:25518020

Interlaced X-ray diffraction computed tomography

PubMed Central

Vamvakeros, Antonios; Jacques, Simon D. M.; Di Michiel, Marco; Senecal, Pierre; Middelkoop, Vesna; Cernik, Robert J.; Beale, Andrew M.

2016-01-01

An X-ray diffraction computed tomography data-collection strategy that allows, post experiment, a choice between temporal and spatial resolution is reported. This strategy enables time-resolved studies on comparatively short timescales, or alternatively allows for improved spatial resolution if the system under study, or components within it, appear to be unchanging. The application of the method for studying an Mn–Na–W/SiO2 fixed-bed reactor in situ is demonstrated. Additionally, the opportunities to improve the data-collection strategy further, enabling post-collection tuning between statistical, temporal and spatial resolutions, are discussed. In principle, the interlaced scanning approach can also be applied to other pencil-beam tomographic techniques, like X-ray fluorescence computed tomography, X-ray absorption fine structure computed tomography, pair distribution function computed tomography and tomographic scanning transmission X-ray microscopy. PMID:27047305

Colovesical fistula causing an uncommon reason for failure of computed tomography colonography: a case report.

PubMed

Neroladaki, Angeliki; Breguet, Romain; Botsikas, Diomidis; Terraz, Sylvain; Becker, Christoph D; Montet, Xavier

2012-07-23

Computed tomography colonography, or virtual colonoscopy, is a good alternative to optical colonoscopy. However, suboptimal patient preparation or colon distension may reduce the diagnostic accuracy of this imaging technique. We report the case of an 83-year-old Caucasian woman who presented with a five-month history of pneumaturia and fecaluria and an acute episode of macrohematuria, leading to a high clinical suspicion of a colovesical fistula. The fistula was confirmed by standard contrast-enhanced computed tomography. Optical colonoscopy was performed to exclude the presence of an underlying colonic neoplasm. Since optical colonoscopy was incomplete, computed tomography colonography was performed, but also failed due to inadequate colon distension. The insufflated air directly accumulated within the bladder via the large fistula. Clinicians should consider colovesical fistula as a potential reason for computed tomography colonography failure.

Computed tomography and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography findings in adrenal candidiasis and histoplasmosis: two cases.

PubMed

Altinmakas, Emre; Guo, Ming; Kundu, Uma R; Habra, Mouhammed Amir; Ng, Chaan

2015-01-01

We report the contrast-enhanced computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography findings in adrenal histoplasmosis and candidiasis. Both demonstrated bilateral hypermetabolic heterogeneous adrenal masses with limited wash-out on delayed CT. Adrenal candidiasis has not been previously reported, nor have the CT wash-out findings in either infection. The adrenal imaging findings are indistinguishable from malignancy, which is more common; but in this setting, physicians should be alert to the differential diagnosis of fungal infections, since it can be equally deadly. Published by Elsevier Inc.

Incidental renal tumours on low-dose CT lung cancer screening exams.

PubMed

Pinsky, Paul F; Dunn, Barbara; Gierada, David; Nath, P Hrudaya; Munden, Reginald; Berland, Lincoln; Kramer, Barnett S

2017-06-01

Introduction Renal cancer incidence has increased markedly in the United States in recent decades, largely due to incidentally detected tumours from computed tomography imaging. Here, we analyze the potential for low-dose computed tomography lung cancer screening to detect renal cancer. Methods The National Lung Screening Trial randomized subjects to three annual screens with either low-dose computed tomography or chest X-ray. Eligibility criteria included 30 + pack-years, current smoking or quit within 15 years, and age 55-74. Subjects were followed for seven years. Low-dose computed tomography screening forms collected information on lung cancer and non-lung cancer abnormalities, including abnormalities below the diaphragm. A reader study was performed on a sample of National Lung Screening Trial low-dose computed tomography images assessing presence of abnormalities below the diaphragms and abnormalities suspicious for renal cancer. Results There were 26,722 and 26,732 subjects enrolled in the low-dose computed tomography and chest X-ray arms, respectively, and there were 104 and 85 renal cancer cases diagnosed, respectively (relative risk = 1.22, 95% CI: 0.9-1.5). From 75,126 low-dose computed tomography screens, there were 46 renal cancer diagnoses within one year. Abnormalities below the diaphragm rates were 39.1% in screens with renal cancer versus 4.1% in screens without (P < 0.001). Cases with abnormalities below the diaphragms had shorter median time to diagnosis than those without (71 vs. 160 days, P = 0.004). In the reader study, 64% of renal cancer cases versus 13% of non-cases had abnormalities below the diaphragms; 55% of cases and 0.8% of non-cases had a finding suspicious for renal cancer (P < 0.001). Conclusion Low-dose computed tomography screens can potentially detect renal cancers. The benefits to harms tradeoff of incidental detection of renal tumours on low-dose computed tomography is unknown.

Meta-Analysis of Stress Myocardial Perfusion Imaging

ClinicalTrials.gov

2017-06-06

Coronary Disease; Echocardiography; Fractional Flow Reserve, Myocardial; Hemodynamics; Humans; Magnetic Resonance Imaging; Myocardial Perfusion Imaging; Perfusion; Predictive Value of Tests; Single Photon Emission Computed Tomography; Positron Emission Tomography; Multidetector Computed Tomography; Echocardiography, Stress; Coronary Angiography

Positron Computed Tomography: Current State, Clinical Results and Future Trends

DOE R&D Accomplishments Database

Schelbert, H. R.; Phelps, M. E.; Kuhl, D. E.

1980-09-01

An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)

Diagnostic dilemma of degenerative joint disease, chronic avascular necrosis or metastasis in planar Tc-99m-methylene diphosphonate planar skeletal scintigraphy excluded by single positron emission computed tomography/computed tomography.

PubMed

Jain, Tarun Kumar; Phulsunga, Rohit Kumar; Basher, Rajender Kumar; Kumar, Narendra; Bhattacharya, Anish; Mittal, Bhagwant Rai

2015-01-01

We present a 71-year-old male patient subjected to skeletal scintigraphy for metastasis work up of prostate cancer. Whole body planar images revealed a solitary focal tracer uptake in left femoral head mimicking as solitary metastatic focus. Single positron emission computed tomography/computed tomography images localized this increased tracer uptake to the subchondral cysts with minimal sclerosis in left femur head with no decrease in size of femur head and was reported as (degenerative joint disease).

Diagnostic dilemma of degenerative joint disease, chronic avascular necrosis or metastasis in planar Tc-99m-methylene diphosphonate planar skeletal scintigraphy excluded by single positron emission computed tomography/computed tomography

PubMed Central

Jain, Tarun Kumar; Phulsunga, Rohit Kumar; Basher, Rajender Kumar; Kumar, Narendra; Bhattacharya, Anish; Mittal, Bhagwant Rai

2015-01-01

We present a 71-year-old male patient subjected to skeletal scintigraphy for metastasis work up of prostate cancer. Whole body planar images revealed a solitary focal tracer uptake in left femoral head mimicking as solitary metastatic focus. Single positron emission computed tomography/computed tomography images localized this increased tracer uptake to the subchondral cysts with minimal sclerosis in left femur head with no decrease in size of femur head and was reported as (degenerative joint disease). PMID:26170582

The early development of medial coronoid disease in growing Labrador retrievers: radiographic, computed tomographic, necropsy and micro-computed tomographic findings.

PubMed

Lau, S F; Wolschrijn, C F; Hazewinkel, H A W; Siebelt, M; Voorhout, G

2013-09-01

Medial coronoid disease (MCD) encompasses lesions of the entire medial coronoid process (MCP), both of the articular cartilage and the subchondral bone. To detect the earliest signs of MCD, radiography and computed tomography were used to monitor the development of MCD in 14 Labrador retrievers, from 6 to 7 weeks of age until euthanasia. The definitive diagnosis of MCD was based on necropsy and micro-computed tomography findings. The frequency of MCD in the dogs studied was 50%. Radiographic findings did not provide evidence of MCD, ulnar subtrochlear sclerosis or blunting of the cranial edge of the MCP. Computed tomography was more sensitive (30.8%) than radiography (0%) in detecting early MCD, with the earliest signs detectable at 14 weeks of age. A combination of the necropsy and micro-computed tomography findings of the MCP showed that MCD was manifested as a lesion of only the subchondral bone in dogs <18 weeks of age. In all dogs (affected and unaffected), there was close contact between the base of the MCP and the proximal radial head in the congruent joints. Computed tomography and micro-computed tomography findings indicated that the lesions of MCD probably originated at the base of the MCP. Copyright © 2013 Elsevier Ltd. All rights reserved.

Angiographic assessment of atherosclerotic load at the lower extremity in patients with diabetic foot and charcot neuro-arthropathy.

PubMed

Çildağ, Mehmet B; Ertuğrul, Bülent M; Köseoğlu, Ömer Fk; Çildağ, Songül; Armstrong, David G

2018-06-01

The aim of this study was to investigate atherosclerotic load at the lower extremity in patients with diabetic foot and charcot neuro-arthropathy and compare them with patients with diabetic foot without charcot neuro-arthropathy. This retrospective study consists of 78 patients with diabetic foot who had lower extremity angiography with antegrade approach. All patients were classified into two groups; neuro ischemic wounds with charcot neuro-arthropathy (30/78) and without charcot neuro-arthropathy (48/78).Atherosclerotic load at the side of diabetic foot was determined by using the Bollinger angiogram scoring method. Comparison of atherosclerotic load between the two groups was performed. The mean of total and infrapopliteal level angiogram scoring of all patients was 33.3 (standard deviation, sd:±17.2) and 29.3 (sd:±15.6), respectively. The mean of total and infrapopliteal level angiogram scoring of neuroischemic wounds with charcot neuro-arthropathy group was 18.1 (sd:±11.6) and 15.7 (sd:±10.4), respectively. The mean of total and infrapopliteal level angiogram scoring of neuroischemic wounds without charcot neuro-arthropathy group was 42.8 (sd:±12.7) and 37.7 (sd:±12.0), respectively. There was a statistically significant difference between the two groups of mean total and infrapopliteal angiogram scoring (p < 0.01). This angiographic study confirms that the atherosclerotic load in patients with diabetic foot and chronic charcot neuro-arthropathy is significantly less than in patients with neuroischemic diabetic foot wounds without chronic charcot neuro-arthropathy. Copyright © 2017. Published by Elsevier Taiwan LLC.

Tomography in Geology: 3D Modeling and Analysis of Structural Features of Rocks Using Computed MicroTomography

NASA Astrophysics Data System (ADS)

Ponomarev, A. A.; Mamadaliev, R. A.; Semenova, T. V.

2016-10-01

The article presents a brief overview of the current state of computed tomography in the sphere of oil and gas production in Russia and in the world. Operation of computed microtomograph Skyscan 1172 is also provided, as well as personal examples of its application in solving geological problems.

Aerosolized intranasal midazolam for safe and effective sedation for quality computed tomography imaging in infants and children.

PubMed

Mekitarian Filho, Eduardo; de Carvalho, Werther Brunow; Gilio, Alfredo Elias; Robinson, Fay; Mason, Keira P

2013-10-01

This pilot study introduces the aerosolized route for midazolam as an option for infant and pediatric sedation for computed tomography imaging. This technique produced predictable and effective sedation for quality computed tomography imaging studies with minimal artifact and no significant adverse events. Copyright © 2013 Mosby, Inc. All rights reserved.

Computed Tomography Measuring Inside Machines

NASA Technical Reports Server (NTRS)

Wozniak, James F.; Scudder, Henry J.; Anders, Jeffrey E.

1995-01-01

Computed tomography applied to obtain approximate measurements of radial distances from centerline of turbopump to leading edges of diffuser vanes in turbopump. Use of computed tomography has significance beyond turbopump application: example of general concept of measuring internal dimensions of assembly of parts without having to perform time-consuming task of taking assembly apart and measuring internal parts on coordinate-measuring machine.

A Heat Pipe Coupled Planar Thermionic Converter: Performance Characterization, Nondestructive Testing, and Evaluation.

DTIC Science & Technology

1992-03-15

Pipes, Computer Modelling, Nondestructive Testing. Tomography , Planar Converter, Cesium Reservoir 19. ABSTRACT (Continue on reverse if necessary and...Investigation ........................ 32 4.3 Computed Tomography ................................ 33 4.4 X-Ray Radiography...25 3.4 LEOS generated output data for Mo-Re converter ................ 26 4.1 Distance along converter imaged by the computed tomography

Nondestructive microimaging during preclinical pin-on-plate testing of novel materials for arthroplasty.

PubMed

Teeter, Matthew G; Langohr, G Daniel G; Medley, John B; Holdsworth, David W

2014-02-01

The purpose of this study was to determine the ability of micro-computed tomography to quantify wear in preclinical pin-on-plate testing of materials for use in joint arthroplasty. Wear testing of CoCr pins articulating against six polyetheretherketone plates was performed using a pin-on-plate apparatus over 2 million cycles. Change in volume due to wear was quantified with gravimetric analysis and with micro-computed tomography, and the volumes were compared. Separately, the volume of polyetheretherketone pin-on-plate specimens that had been soaking in fluid for 52 weeks was quantified with both gravimetric analysis and micro-computed tomography, and repeated after drying. The volume change with micro-computed tomography was compared to the mass change with gravimetric analysis. The mean wear volume measured was 8.02 ± 6.38 mm(3) with gravimetric analysis and 6.76 ± 5.38 mm(3) with micro-computed tomography (p = 0.06). Micro-computed tomography volume measurements did not show a statistically significant change with drying for either the plates (p = 0.60) or the pins (p = 0.09), yet drying had a significant effect on the gravimetric mass measurements for both the plates (p = 0.03) and the pins (p = 0.04). Micro-computed tomography provided accurate measurements of wear in polyetheretherketone pin-on-plate test specimens, and no statistically significant change was caused by fluid uptake. Micro-computed tomography quantifies wear depth and wear volume, mapped to the specific location of damage on the specimen, and is also capable of examining subsurface density as well as cracking. Its noncontact, nondestructive nature makes it ideal for preclinical testing of materials, in which further additional analysis techniques may be utilized.

Preoperative (3-dimensional) computed tomography lung reconstruction before anatomic segmentectomy or lobectomy for stage I non-small cell lung cancer.

PubMed

Chan, Ernest G; Landreneau, James R; Schuchert, Matthew J; Odell, David D; Gu, Suicheng; Pu, Jiantao; Luketich, James D; Landreneau, Rodney J

2015-09-01

Accurate cancer localization and negative resection margins are necessary for successful segmentectomy. In this study, we evaluate a newly developed software package that permits automated segmentation of the pulmonary parenchyma, allowing 3-dimensional assessment of tumor size, location, and estimates of surgical margins. A pilot study using a newly developed 3-dimensional computed tomography analytic software package was performed to retrospectively evaluate preoperative computed tomography images of patients who underwent segmentectomy (n = 36) or lobectomy (n = 15) for stage 1 non-small cell lung cancer. The software accomplishes an automated reconstruction of anatomic pulmonary segments of the lung based on bronchial arborization. Estimates of anticipated surgical margins and pulmonary segmental volume were made on the basis of 3-dimensional reconstruction. Autosegmentation was achieved in 72.7% (32/44) of preoperative computed tomography images with slice thicknesses of 3 mm or less. Reasons for segmentation failure included local severe emphysema or pneumonitis, and lower computed tomography resolution. Tumor segmental localization was achieved in all autosegmented studies. The 3-dimensional computed tomography analysis provided a positive predictive value of 87% in predicting a marginal clearance greater than 1 cm and a 75% positive predictive value in predicting a margin to tumor diameter ratio greater than 1 in relation to the surgical pathology assessment. This preoperative 3-dimensional computed tomography analysis of segmental anatomy can confirm the tumor location within an anatomic segment and aid in predicting surgical margins. This 3-dimensional computed tomography information may assist in the preoperative assessment regarding the suitability of segmentectomy for peripheral lung cancers. Published by Elsevier Inc.

Role of post-mapping computed tomography in virtual-assisted lung mapping.

PubMed

Sato, Masaaki; Nagayama, Kazuhiro; Kuwano, Hideki; Nitadori, Jun-Ichi; Anraku, Masaki; Nakajima, Jun

2017-02-01

Background Virtual-assisted lung mapping is a novel bronchoscopic preoperative lung marking technique in which virtual bronchoscopy is used to predict the locations of multiple dye markings. Post-mapping computed tomography is performed to confirm the locations of the actual markings. This study aimed to examine the accuracy of marking locations predicted by virtual bronchoscopy and elucidate the role of post-mapping computed tomography. Methods Automated and manual virtual bronchoscopy was used to predict marking locations. After bronchoscopic dye marking under local anesthesia, computed tomography was performed to confirm the actual marking locations before surgery. Discrepancies between marking locations predicted by the different methods and the actual markings were examined on computed tomography images. Forty-three markings in 11 patients were analyzed. Results The average difference between the predicted and actual marking locations was 30 mm. There was no significant difference between the latest version of the automated virtual bronchoscopy system (30.7 ± 17.2 mm) and manual virtual bronchoscopy (29.8 ± 19.1 mm). The difference was significantly greater in the upper vs. lower lobes (37.1 ± 20.1 vs. 23.0 ± 6.8 mm, for automated virtual bronchoscopy; p < 0.01). Despite this discrepancy, all targeted lesions were successfully resected using 3-dimensional image guidance based on post-mapping computed tomography reflecting the actual marking locations. Conclusions Markings predicted by virtual bronchoscopy were dislocated from the actual markings by an average of 3 cm. However, surgery was accurately performed using post-mapping computed tomography guidance, demonstrating the indispensable role of post-mapping computed tomography in virtual-assisted lung mapping.

Utility of screening computed tomography of chest, abdomen and pelvis in patients after heart transplantation.

PubMed

Dasari, Tarun W; Pavlovic-Surjancev, Biljana; Dusek, Linda; Patel, Nilamkumar; Heroux, Alain L

2011-12-01

Malignancy is a late cause of mortality in heart transplant recipients. It is unknown if screening computed tomography scan would lead to early detection of such malignancies or serious vascular anomalies post heart transplantation. This is a single center observational study of patients undergoing surveillance computed tomography of chest, abdomen and pelvis at least 5 years after transplantation. Abnormal findings, included pulmonary nodules, lymphadenopathy and intra-thoracic and intra-abdominal masses and vascular anomalies such as abdominal aortic aneurysm. The clinical follow up of each of these major abnormal findings is summarized. A total of 63 patients underwent computed tomography scan of chest, abdomen and pelvis at least 5 years after transplantation. Of these, 54 (86%) were male and 9 (14%) were female. Mean age was 52±9.2 years. Computed tomography revealed 1 lung cancer (squamous cell) only. Non specific pulmonary nodules were seen in 6 patients (9.5%). The most common incidental finding was abdominal aortic aneurysms (N=6 (9.5%)), which necessitated follow up computed tomography (N=5) or surgery (N=1). Mean time to detection of abdominal aortic aneurysms from transplantation was 14.6±4.2 years. Mean age at the time of detection of abdominal aortic aneurysms was 74.5±3.2 years. Screening computed tomography scan in patients 5 years from transplantation revealed only one malignancy but lead to increased detection of abdominal aortic aneurysms. Thus the utility is low in terms of detection of malignancy. Based on this study we do not recommend routine computed tomography post heart transplantation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Petamenophis (Padiamenemipet), an Egyptian Child Mummy Protected for Eternity: Revelation by Multidetector Computed Tomography.

PubMed

Martina, Maria Cristina; Cesarani, Federico; Boano, Rosa; Fiore Marochetti, Elisa; Gandini, Giovanni

The objective of our work was to report the most recent findings obtained with multidetector computed tomography of a child mummy from the Roman period (119-123 CE) housed at the Egyptian Museum in Turin, Italy. Multidetector computed tomography and postprocessing were applied to understand the embalming techniques, the nature of a foreign object, and anthropometrical values. The information was compared with that from other mummies that were buried in the same tomb, but today housed in different museums. New information regarding the embalming technique was revealed. Multidetector computed tomography allowed the identification of a knife-like metallic object, probably an amulet for the child's protection in the afterlife. Multidetector computed tomography and image postprocessing confirm their valuable role in noninvasive studies in ancient mummies and provided evidence of a unique cultural practice in the late history of Ancient Egypt such as placing a knife possibly as an amulet.

Diagnosis of sinusoidal obstruction syndrome by positron emission tomography/computed tomography: report of two cases treated by defibrotide.

PubMed

Gauthé, Mathieu; Bozec, Laurence; Bedossa, Pierre

2014-11-01

Sinusoidal obstruction syndrome (SOS) is a potentially fatal liver injury that mainly occurs after myeloablative chemotherapy. We report two cases of SOS investigated by 18F-fluorodeoxyglucose positron emission tomography/computed tomography and treated with defibrotide. © 2014 by the American Association for the Study of Liver Diseases.

Measuring Weld Profiles By Computer Tomography

NASA Technical Reports Server (NTRS)

Pascua, Antonio G.; Roy, Jagatjit

1990-01-01

Noncontacting, nondestructive computer tomography system determines internal and external contours of welded objects. System makes it unnecessary to take metallurgical sections (destructive technique) or to take silicone impressions of hidden surfaces (technique that contaminates) to inspect them. Measurements of contours via tomography performed 10 times as fast as measurements via impression molds, and tomography does not contaminate inspected parts.

Parallel Computing for the Computed-Tomography Imaging Spectrometer

NASA Technical Reports Server (NTRS)

Lee, Seungwon

2008-01-01

This software computes the tomographic reconstruction of spatial-spectral data from raw detector images of the Computed-Tomography Imaging Spectrometer (CTIS), which enables transient-level, multi-spectral imaging by capturing spatial and spectral information in a single snapshot.

[The comparison of the expansion of polyps according to the Ki-67 and computed tomography scores].

PubMed

Aydin, Sedat; Sanli, Arif; Tezer, Ilter; Hardal, Umit; Barişik, Nagehan Ozdemir

2009-01-01

The disease extention in nasal polyps was compared by using the mitotic activity rates and the computed tomography scores. This study was conducted on 19 nasal polyposis patients (8 males, 11 females; mean age 40.0+/-13.7 years; range 20 to 63 years). The preoperative computed tomography records of the patients were evaluated according to the Lund-Mackay grading system. The polyp tissues of the same patients were stained with the Ki-67 antigen for immunohistochemical evaluation. The correlation between the radiologic results and the Ki-67 values was compared by means of the Spearman's correlation test. The mean computed tomography score was observed as 14.3+/-4.7 (range 7-24). The mean Ki-67 score resulting from the immunohistochemical staining was calculated as 24.3+/-18.5 (range 3.3-73.5%). A significant correlation was determined between the Ki-67 values and the computed tomography scores. ("Spearman's" correlation factor: 0.677; p<0.001). As the mitotic activity rate of nasal polyps increases, both the volume of the polyps and the computed tomography scores increase as a result of the blockage of the sinus ostiums by the increased polyp volume.

A Projection Quality-Driven Tube Current Modulation Method in Cone-Beam CT for IGRT: Proof of Concept.

PubMed

Men, Kuo; Dai, Jianrong

2017-12-01

To develop a projection quality-driven tube current modulation method in cone-beam computed tomography for image-guided radiotherapy based on the prior attenuation information obtained by the planning computed tomography and then evaluate its effect on a reduction in the imaging dose. The QCKV-1 phantom with different thicknesses (0-400 mm) of solid water upon it was used to simulate different attenuation (μ). Projections were acquired with a series of tube current-exposure time product (mAs) settings, and a 2-dimensional contrast to noise ratio was analyzed for each projection to create a lookup table of mAs versus 2-dimensional contrast to noise ratio, μ. Before a patient underwent computed tomography, the maximum attenuation [Formula: see text] within the 95% range of each projection angle (θ) was estimated according to the planning computed tomography images. Then, a desired 2-dimensional contrast to noise ratio value was selected, and the mAs setting at θ was calculated with the lookup table of mAs versus 2-dimensional contrast to noise ratio,[Formula: see text]. Three-dimensional cone-beam computed tomography images were reconstructed using the projections acquired with the selected mAs. The imaging dose was evaluated with a polymethyl methacrylate dosimetry phantom in terms of volume computed tomography dose index. Image quality was analyzed using a Catphan 503 phantom with an oval body annulus and a pelvis phantom. For the Catphan 503 phantom, the cone-beam computed tomography image obtained by the projection quality-driven tube current modulation method had a similar quality to that of conventional cone-beam computed tomography . However, the proposed method could reduce the imaging dose by 16% to 33% to achieve an equivalent contrast to noise ratio value. For the pelvis phantom, the structural similarity index was 0.992 with a dose reduction of 39.7% for the projection quality-driven tube current modulation method. The proposed method could reduce the additional dose to the patient while not degrading the image quality for cone-beam computed tomography. The projection quality-driven tube current modulation method could be especially beneficial to patients who undergo cone-beam computed tomography frequently during a treatment course.

Shock Index Correlates with Extravasation on Angiographs of Gastrointestinal Hemorrhage: A Logistics Regression Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakasone, Yutaka, E-mail: n-yutaka@cd5.so-net.ne.jp; Ikeda, Osamu; Yamashita, Yasuyuki

We applied multivariate analysis to the clinical findings in patients with acute gastrointestinal (GI) hemorrhage and compared the relationship between these findings and angiographic evidence of extravasation. Our study population consisted of 46 patients with acute GI bleeding. They were divided into two groups. In group 1 we retrospectively analyzed 41 angiograms obtained in 29 patients (age range, 25-91 years; average, 71 years). Their clinical findings including the shock index (SI), diastolic blood pressure, hemoglobin, platelet counts, and age, which were quantitatively analyzed. In group 2, consisting of 17 patients (age range, 21-78 years; average, 60 years), we prospectively appliedmore » statistical analysis by a logistics regression model to their clinical findings and then assessed 21 angiograms obtained in these patients to determine whether our model was useful for predicting the presence of angiographic evidence of extravasation. On 18 of 41 (43.9%) angiograms in group 1 there was evidence of extravasation; in 3 patients it was demonstrated only by selective angiography. Factors significantly associated with angiographic visualization of extravasation were the SI and patient age. For differentiation between cases with and cases without angiographic evidence of extravasation, the maximum cutoff point was between 0.51 and 0.0.53. Of the 21 angiograms obtained in group 2, 13 (61.9%) showed evidence of extravasation; in 1 patient it was demonstrated only on selective angiograms. We found that in 90% of the cases, the prospective application of our model correctly predicted the angiographically confirmed presence or absence of extravasation. We conclude that in patients with GI hemorrhage, angiographic visualization of extravasation is associated with the pre-embolization SI. Patients with a high SI value should undergo study to facilitate optimal treatment planning.« less

Basilar artery atherosclerotic plaques in paramedian and lacunar pontine infarctions: a high-resolution MRI study.

PubMed

Klein, Isabelle F; Lavallée, Philippa C; Mazighi, Mikael; Schouman-Claeys, Elisabeth; Labreuche, Julien; Amarenco, Pierre

2010-07-01

Pontine infarction is most often related to basilar artery atherosclerosis when the lesion abuts on the basal surface (paramedian pontine infarction), whereas small medial pontine lesion is usually attributed to small vessel lipohyalinosis. A previous study has found that high-resolution MRI can detect basilar atherosclerotic plaques in up to 70% of patient with paramedian pontine infarction, even in patients with normal angiograms, but none has evaluated the presence of basilar artery plaque by high-resolution MRI in patients with small medial pontine lesion in the medial part of the pons. Consecutive patients with pontine infarction underwent basilar angiography using time-of-flight and contrast-enhanced 3-dimensional MR angiography to assess the presence of basilar artery stenosis and high-resolution MRI to assess the presence of atherosclerotic plaque. Basilar artery angiogram was scored as "normal," "irregular," or "stenosed" >or=30%" and basilar artery by high-resolution MRI was scored as "normal" or "presence of plaque." Medial pontine infarcts were divided into paramedian pontine infarction and small medial pontine lesion groups. Forty-one patients with pontine infarction were included, 26 with paramedian pontine infarction and 15 with small medial pontine lesion. High-resolution MRI detected basilar artery atherosclerosis in 42% of patients with a pontine infarction and normal basilar angiograms. Among patients with paramedian pontine infarction, 65% had normal basilar angiograms but 77% had basilar artery atherosclerosis detected on high-resolution MRI. Among patients with small medial pontine lesion, 46% had normal basilar angiograms but 73% had basilar artery plaques detected on by high-resolution MRI. This study suggests that medial pontine lacunes may be due to a penetrating artery disease secondary to basilar artery atherosclerosis. High-resolution MRI could help precise stroke subtyping.

Just Scan It!-Weapon Reconstruction in Computed Tomography on Historical and Current Swiss Military Guns.

PubMed

Franckenberg, Sabine; Binder, Thomas; Bolliger, Stephan; Thali, Michael J; Ross, Steffen G

2016-09-01

Cross-sectional imaging, such as computed tomography, has been increasingly implemented in both historic and recent postmortem forensic investigations. It aids in determining cause and manner of death as well as in correlating injuries to possible weapons. This study illuminates the feasibility of reconstructing guns in computed tomography and gives a distinct overview of historic and recent Swiss Army guns.

The use of computed tomography to diagnose chronic shoulder arthritis in an American white pelican (Pelecanus erythrorhynchos).

PubMed

Whitehead, Michelle C; Parker, Dennilyn L

2015-03-01

An American white pelican was presented with a complete left wing droop and no abnormal findings on conventional radiography. Computed tomography was used to diagnose chronic shoulder arthritis as a sequela to a suspected traumatic compressive fracture. This is the first case report to describe use of computed tomography to evaluate the avian shoulder joint.

Embracing Statistical Challenges in the Information Technology Age

DTIC Science & Technology

2006-01-01

computation and feature selection. Moreover, two research projects on network tomography and arctic cloud detection are used throughout the paper to bring...prominent Network Tomography problem, origin- destination (OD) traffic estimation. It demonstrates well how the two modes of data collection interact...software debugging (Biblit et al, 2005 [2]), and network tomography for computer network management. Computer sys- tem problems exist long before the IT

Computed Tomography For Internal Inspection Of Castings

NASA Technical Reports Server (NTRS)

Hanna, Timothy L.

1995-01-01

Computed tomography used to detect internal flaws in metal castings before machining and otherwise processing them into finished parts. Saves time and money otherwise wasted on machining and other processing of castings eventually rejected because of internal defects. Knowledge of internal defects gained by use of computed tomography also provides guidance for changes in foundry techniques, procedures, and equipment to minimize defects and reduce costs.

The Impact of Computed Tomography on Decision Making in Tibial Plateau Fractures.

PubMed

Castiglia, Marcello Teixeira; Nogueira-Barbosa, Marcello Henrique; Messias, Andre Marcio Vieira; Salim, Rodrigo; Fogagnolo, Fabricio; Schatzker, Joseph; Kfuri, Mauricio

2018-02-14

Schatzker introduced one of the most used classification systems for tibial plateau fractures, based on plain radiographs. Computed tomography brought to attention the importance of coronal plane-oriented fractures. The goal of our study was to determine if the addition of computed tomography would affect the decision making of surgeons who usually use the Schatzker classification to assess tibial plateau fractures. Image studies of 70 patients who sustained tibial plateau fractures were uploaded to a dedicated homepage. Every patient was linked to a folder which contained two radiographic projections (anteroposterior and lateral), three interactive videos of computed tomography (axial, sagittal, and coronal), and eight pictures depicting tridimensional reconstructions of the tibial plateau. Ten attending orthopaedic surgeons, who were blinded to the cases, were granted access to the homepage and assessed each set of images in two different rounds, separated to each other by an interval of 2 weeks. Each case was evaluated in three steps, where surgeons had access, respectively to radiographs, two-dimensional videos of computed tomography, and three-dimensional reconstruction images. After every step, surgeons were asked to present how would they classify the case using the Schatzker system and which surgical approaches would be appropriate. We evaluated the inter- and intraobserver reliability of the Schatzker classification using the Kappa concordance coefficient, as well as the impact of computed tomography in the decision making regarding the surgical approach for each case, by using the chi-square test and likelihood ratio. The interobserver concordance kappa coefficients after each assessment step were, respectively, 0.58, 0.62, and 0.64. For the intraobserver analysis, the coefficients were, respectively, 0.76, 0.75, and 0.78. Computed tomography changed the surgical approach selection for the types II, V, and VI of Schatzker ( p  < 0.01). The addition of computed tomography scans to plain radiographs improved the interobserver reliability of Schatzker classification. Computed tomography had a statistically significant impact in the selection of surgical approaches for the lateral tibial plateau. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Functional anatomy of the prostate: implications for treatment planning.

PubMed

McLaughlin, Patrick W; Troyer, Sara; Berri, Sally; Narayana, Vrinda; Meirowitz, Amichay; Roberson, Peter L; Montie, James

2005-10-01

To summarize the functional anatomy relevant to prostate cancer treatment planning. Coronal, axial, and sagittal T2 magnetic resonance imaging (MRI) and MRI angiography were fused by mutual information and registered with computed tomography (CT) scan data sets to improve definition of zonal anatomy of the prostate and critical adjacent structures. The three major prostate zones (inner, outer, and anterior fibromuscular) are visible by T2 MRI imaging. The bladder, bladder neck, and internal (preprostatic) sphincter are a continuous muscular structure and clear definition of the preprostatic sphincter is difficult by MRI. Transition zone hypertrophy may efface the bladder neck and internal sphincter. The external "lower" sphincter is clearly visible by T2 MRI with wide variations in length. The critical erectile structures are the internal pudendal artery (defined by MRI angiogram or T2 MRI), corpus cavernosum, and neurovascular bundle. The neurovascular bundle is visible along the posterior lateral surface of the prostate on CT and MRI, but its terminal branches (cavernosal nerves) are not visible and must be defined by their relationship to the urethra within the genitourinary diaphragm. Visualization of the ejaculatory ducts within the prostate is possible on sagittal MRI. The anatomy of the prostate-rectum interface is clarified by MRI, as is the potentially important distinction of rectal muscle and rectal mucosa. Improved understanding of functional anatomy and imaging of the prostate and critical adjacent structures will improve prostate radiation therapy by improvement of dose and toxicity correlation, limitation of dose to critical structures, and potential improvement in post therapy quality of life.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oshima, M.; Port, S.C.; Ray, G.

Forty-two patients (pts) with 1VD(greater than or equal to 70% stenosis and no prior infarction) undergoing PTCA provide a model to study the efficacy with which non-invasive tests can a) detect stress induced ischemia and b) reflect the reduction in stress induced ischemia expected from arteriographically successful PTCA. The diseased coronary was the right in 12, the circumflex in 3 and the LAD in 27 pts. Pre- and post- PTCA paired data were available from treadmill (ETT), planar thallium (Qual-T1), 7 pinhole tomography and 1st pass radionuclide angiograms (RNA) in 29, 26, 31 and 25 pts. After tomographic images weremore » digitized and analyzed by a computer, the intensity (=area/range, a numerical index of the severity of a defect) served as a quantitative T1 (Quant-T1). Criteria for ischemia were: significant ST change on ETT, unequivocal stress defects on Qual-T1, Quant-T1 intensity greater than or equal to 2.0, and exercise ejection fraction (Ex EF) greater than or equal to 0.55 or a new wall motion abnormality on Ex RNA. Ex EF was .61 +- .13 pre- and .63 +- .10 post-PTCA (p=NS). Quant-T1 intensity was 9.5 +- 7.1 pre- and 4.0 +- 5.5 post-PTCA (p=.0003). T1 testing was the most sensitive for detecting ischemia pre-PTCA. However, given an ischemic response pre-PTCA, the RNA showed the greatest trend toward normalization post-PTCA. If one test must be chosen Quant-T1 seems most appropriate in the evaluation of pre- and post- PTCA pts with 1VD.« less

General practitioner understanding of abbreviations used in hospital discharge letters.

PubMed

Chemali, Mark; Hibbert, Emily J; Sheen, Adrian

2015-08-03

To determine the incidence of abbreviation use in electronic hospital discharge letters (eDLs) and general practitioner understanding of abbreviations used in eDLsDesign, setting and participants: Retrospective audit of abbreviation use in 200 sequential eDLs was conducted at Nepean Hospital, Sydney, a tertiary referral centre, from 18 December to 31 December 2012. The 15 most commonly used abbreviations and five clinically important abbreviations were identified from the audit. A survey questionnaire using these abbreviations in context was then mailed to 240 GPs in the area covered by the Nepean Blue Mountains Local Health District to determine their understanding of these abbreviations. Number of abbreviations and frequency of their use in eDLs, and GPs' understanding of abbreviations used in the survey. 321 abbreviations were identified in the eDL audit; 48.6% were used only once. Fifty five per cent of GPs (132) responded to the survey. No individual abbreviation was correctly interpreted by all GPs. Six abbreviations were misinterpreted by more than a quarter of GPs. These were SNT (soft non-tender), TTE (transthoracic echocardiogram), EST (exercise stress test), NKDA (no known drug allergies), CTPA (computed tomography pulmonary angiogram), ORIF (open reduction and internal fixation). These abbreviations were interpreted incorrectly by 47.0% (62), 33.3% (44), 33.3% (44) 32.6% (43), 31.1% (41) and 28.0% (37) of GPs, respectively. Abbreviations used in hospital eDLs are not well understood by the GPs who receive them. This has potential to adversely affect patient care in the transition from hospital to community care.

Incidental Finding of Bronchopulmonary Sequestration in a 64-Year-Old Female.

PubMed

Tunsupon, Pichapong; Arshad, Ayesha; Patel, Sumit; Mador, M Jeffery

2017-01-01

Bronchopulmonary sequestration is a congenital abnormality of the primitive foregut. In adults, the typical age at presentation is 20-25 years. A 64-year-old female was referred for evaluation of an 8 × 6-cm right lower lobe cystic lesion. Her medical history was significant for recurrent right lower lobe pneumonia requiring multiple hospitalizations. Her physical examination was significant for crackles at the right lung base. Computed tomography (CT) of the chest with contrast showed cystic changes with thickened septation of the medial segment of the right lower lobe lacking distinct visceral pleura and with arterial supply from the anomalous branch of the thoracic aorta arising near the celiac trunk. Pulmonary angiography confirmed the diagnosis of intralobar pulmonary sequestration. The patient underwent celiac endovascular coil embolization of the anomalous artery to lessen the risk of hemorrhage prior to video-assisted thoracoscopic surgery (VATS) resection of the right lower lobe. She recovered well and was discharged home 1 week after VATS lobectomy. Follow-up CT of the chest 2 months later showed normal postsurgical changes related to right lower lobe lobectomy. The patient remained asymptomatic and resumed her daily activities. Pulmonary sequestration can present with recurrent pneumonia in late adulthood. Physicians must review any previous imaging studies of the chest to identify the structural abnormality and be cognizant of differential diagnoses such as infected cystic bronchiectasis, bronchogenic cyst, congenital diaphragmatic hernia, or cystic adenomatoid malformation that can occur in conjunction with bronchopulmonary sequestration. Pulmonary angiogram is the gold standard to confirm the diagnosis of bronchopulmonary sequestration. Surgical resection is the standard of care.

An algorithm for intelligent sorting of CT-related dose parameters.

PubMed

Cook, Tessa S; Zimmerman, Stefan L; Steingall, Scott R; Boonn, William W; Kim, Woojin

2012-02-01

Imaging centers nationwide are seeking innovative means to record and monitor computed tomography (CT)-related radiation dose in light of multiple instances of patient overexposure to medical radiation. As a solution, we have developed RADIANCE, an automated pipeline for extraction, archival, and reporting of CT-related dose parameters. Estimation of whole-body effective dose from CT dose length product (DLP)--an indirect estimate of radiation dose--requires anatomy-specific conversion factors that cannot be applied to total DLP, but instead necessitate individual anatomy-based DLPs. A challenge exists because the total DLP reported on a dose sheet often includes multiple separate examinations (e.g., chest CT followed by abdominopelvic CT). Furthermore, the individual reported series DLPs may not be clearly or consistently labeled. For example, "arterial" could refer to the arterial phase of the triple liver CT or the arterial phase of a CT angiogram. To address this problem, we have designed an intelligent algorithm to parse dose sheets for multi-series CT examinations and correctly separate the total DLP into its anatomic components. The algorithm uses information from the departmental PACS to determine how many distinct CT examinations were concurrently performed. Then, it matches the number of distinct accession numbers to the series that were acquired and anatomically matches individual series DLPs to their appropriate CT examinations. This algorithm allows for more accurate dose analytics, but there remain instances where automatic sorting is not feasible. To ultimately improve radiology patient care, we must standardize series names and exam names to unequivocally sort exams by anatomy and correctly estimate whole-body effective dose.

Microsurgical Repair of Ruptured Aneurysms Associated with Moyamoya-Pattern Collateral Vessels of the Middle Cerebral Artery: A Report of Two Cases.

PubMed

Lang, Min; Moore, Nina Z; Witek, Alex M; Kshettry, Varun R; Bain, Mark D

2017-09-01

Patients with Moyamoya or other intracranial steno-occlusive disease are at risk for developing aneurysms associated with flow through collateral vessels. Because these lesions are rare, the optimal management remains unclear. Here, we describe 2 cases of microsurgical repair of ruptured collateral vessel aneurysms associated with middle cerebral artery (MCA) occlusion. The first patient was a 61-year-old man who presented with right frontal and intraventricular hemorrhage. Angiography revealed chronic right M1 occlusion and a 3-mm spherical lenticulostriate aneurysm. The frontal lobe hematoma was evacuated to reveal the aneurysm, which was safely cauterized and resected by coagulating and dividing the lenticulostriate parent vessel. The procedure was carried out with neuronavigation guidance and intraoperative neuromonitoring. The patient was discharged with no neurologic deficits. The second patient was a 53-year-old woman who presented with subarachnoid and intracerebral hemorrhage. Computed tomography angiogram showed a 2-mm saccular MCA aneurysm. Emergency left decompressive hemicraniectomy and hematoma evacuation were performed. The aneurysm, arising from a small collateral type vessel, was safely clipped without complications. Postoperative angiography revealed absence of the superior MCA trunk with a dense network of collateral vessels at the site of the clipped aneurysm. The patient recovered well and was ambulating independently 6 months postoperatively. No rebleeding occurred in the 2 patients. Our experience suggests that patients with MCA occlusion can harbor associated aneurysms related to flow through collateral vessels and can present with hemorrhage. Microsurgical repair of these aneurysms can be performed safely to prevent rebleeding. Copyright © 2017 Elsevier Inc. All rights reserved.

Descriptive Analysis of the Arterial Supply to the Auricle in Patients with Unilateral Microtia

PubMed Central

Márquez-Gutiérrez, Erik Agustín; Gutiérrez-Gómez del Hierro, Claudia; Pereyra-Arzate, Jorge Enrique; Rivera-Martínez, Rodolfo

2017-01-01

Background: Microtia is a congenital auricular deformity that occurs in 1:5,000–10,000 births. It can cause severe impairment to the patient’s self-esteem and problems regarding social integration. Multiple measures have been described in attempt to better operative outcomes of these patients. We used computed tomography (CT) angiography to analyze the vascular pattern of the auricular region before surgery. Methods: Fourteen patients with unilateral microtia were included. All underwent CT angiogram plus tridimensional reconstruction. Both healthy and microtic auricles were analyzed descriptively in terms of main arterial supply, pattern, diameter of subbranches, and angulation. The sample was divided in 2 age groups for better understanding of the data. Results: Blood supply to the auricle was found to depend on 2 main vessels: temporal superficial artery (TSA) and its subbranches (superior, middle, and lower branch) and posterior auricular (PA) artery. In the microtic group, TSA was the dominant artery in 13 of 14 cases (92%). Superior, middle, and inferior branches were present in 4, 3, and 0 cases, respectively. Three of the microtic auricles presented supply from PA artery, from which in 1 case, it represented the only supply to the region. Conclusions: There is wide variability in the blood supply of both healthy and microtic auricles; however, we were able to identify some tendencies in our sample. Further research is needed to prove the benefit of a preoperative imaging study in these patients. Still, in our experience, we found it useful as a complement for surgical planning. PMID:29632773

Standardized methodology for transfemoral transcatheter aortic valve replacement with the Edwards Sapien XT valve under fluoroscopy guidance.

PubMed

Kasel, Albert M; Shivaraju, Anupama; Schneider, Stephan; Krapf, Stephan; Oertel, Frank; Burgdorf, Christof; Ott, Ilka; Sumer, Christian; Kastrati, Adnan; von Scheidt, Wolfgang; Thilo, Christian

2014-09-01

To provide a simplified, standardized methodology for a successful transfemoral transcatheter aortic valve replacement (TAVR) procedure with the Sapien XT valve in patients with severe aortic stenosis (AS). TAVR is currently reserved for patients with severe, symptomatic AS who are inoperable or at high operative risk. In many institutions, TAVR is performed under general anesthesia with intubation or with conscious sedation. In addition, many institutions still use transesophageal echo (TEE) during the procedure for aortic root angulations and positioning of the valve prior to implantation. Methods. We enrolled 100 consecutive patients (mean age, 80 ± 7 years; range, 50-94 years; female n=59) with severe symptomatic AS. Annulus measurements were based on computed tomography angiograms. All patients underwent fluoroscopy-guided transfemoral TAVR with little to no sedation and without simultaneous TEE. TAVR was predominantly performed with the use of local and central analgesics; only 36% of our cohort received conscious sedation. Procedural success of TAVR was 99%. Transthoracic echocardiography before discharge excluded aortic regurgitation (AR) >2 in all patients (AR >1; n=6). In-hospital stroke rate was 6%. The vessel closure system was successfully employed in 96%. Major vascular complication rate was 1%. The 30-day mortality was 2%. Fluoroscopy-guided TAVR with the use of just analgesics with or without conscious sedation is safe and effective, and this potentially enables a more time-effective and cost-effective procedure. This paper provides simplified, stepwise guidance on how to perform transfemoral TAVR with the Sapien XT valve.

Virtual Reality Cerebral Aneurysm Clipping Simulation With Real-time Haptic Feedback

PubMed Central

Alaraj, Ali; Luciano, Cristian J.; Bailey, Daniel P.; Elsenousi, Abdussalam; Roitberg, Ben Z.; Bernardo, Antonio; Banerjee, P. Pat; Charbel, Fady T.

2014-01-01

Background With the decrease in the number of cerebral aneurysms treated surgically and the increase of complexity of those treated surgically, there is a need for simulation-based tools to teach future neurosurgeons the operative techniques of aneurysm clipping. Objective To develop and evaluate the usefulness of a new haptic-based virtual reality (VR) simulator in the training of neurosurgical residents. Methods A real-time sensory haptic feedback virtual reality aneurysm clipping simulator was developed using the Immersive Touch platform. A prototype middle cerebral artery aneurysm simulation was created from a computed tomography angiogram. Aneurysm and vessel volume deformation and haptic feedback are provided in a 3-D immersive VR environment. Intraoperative aneurysm rupture was also simulated. Seventeen neurosurgery residents from three residency programs tested the simulator and provided feedback on its usefulness and resemblance to real aneurysm clipping surgery. Results Residents felt that the simulation would be useful in preparing for real-life surgery. About two thirds of the residents felt that the 3-D immersive anatomical details provided a very close resemblance to real operative anatomy and accurate guidance for deciding surgical approaches. They believed the simulation is useful for preoperative surgical rehearsal and neurosurgical training. One third of the residents felt that the technology in its current form provided very realistic haptic feedback for aneurysm surgery. Conclusion Neurosurgical residents felt that the novel immersive VR simulator is helpful in their training especially since they do not get a chance to perform aneurysm clippings until very late in their residency programs. PMID:25599200

Role of Adding Spironolactone and Renal Denervation in True Resistant Hypertension: One-Year Outcomes of Randomized PRAGUE-15 Study.

PubMed

Rosa, Ján; Widimský, Petr; Waldauf, Petr; Lambert, Lukáš; Zelinka, Tomáš; Táborský, Miloš; Branny, Marian; Toušek, Petr; Petrák, Ondřej; Čurila, Karol; Bednář, František; Holaj, Robert; Štrauch, Branislav; Václavík, Jan; Nykl, Igor; Krátká, Zuzana; Kociánová, Eva; Jiravský, Otakar; Rappová, Gabriela; Indra, Tomáš; Widimský, Jiří

2016-02-01

This randomized, multicenter study compared the relative efficacy of renal denervation (RDN) versus pharmacotherapy alone in patients with true resistant hypertension and assessed the effect of spironolactone addition. We present here the 12-month data. A total of 106 patients with true resistant hypertension were enrolled in this study: 52 patients were randomized to RDN and 54 patients to the spironolactone addition, with baseline systolic blood pressure of 159±17 and 155±17 mm Hg and average number of drugs 5.1 and 5.4, respectively. Twelve-month results are available in 101 patients. The intention-to-treat analysis found a comparable mean 24-hour systolic blood pressure decline of 6.4 mm Hg, P=0.001 in RDN versus 8.2 mm Hg, P=0.002 in the pharmacotherapy group. Per-protocol analysis revealed a significant difference of 24-hour systolic blood pressure decline between complete RDN (6.3 mm Hg, P=0.004) and the subgroup where spironolactone was added, and this continued within the 12 months (15 mm Hg, P= 0.003). Renal artery computed tomography angiograms before and after 1 year post-RDN did not reveal any relevant changes. This study shows that over a period of 12 months, RDN is safe, with no serious side effects and no major changes in the renal arteries. RDN in the settings of true resistant hypertension with confirmed compliance is not superior to intensified pharmacological treatment. Spironolactone addition (if tolerated) seems to be more effective in blood pressure reduction. © 2015 American Heart Association, Inc.

Limitations of PET/CT in the Detection of Occult N1 Metastasis in Clinical Stage I(T1-2aN0) Non-Small Cell Lung Cancer for Staging Prior to Stereotactic Body Radiotherapy.

PubMed

Akthar, Adil S; Ferguson, Mark K; Koshy, Matthew; Vigneswaran, Wickii T; Malik, Renuka

2017-02-01

Patients receiving stereotactic body radiotherapy for stage I non-small cell lung cancer are typically staged clinically with positron emission tomography-computed tomography. Currently, limited data exist for the detection of occult hilar/peribronchial (N1) disease. We hypothesize that positron emission tomography-computed tomography underestimates spread of cancer to N1 lymph nodes and that future stereotactic body radiotherapy patients may benefit from increased pathologic evaluation of N1 nodal stations in addition to N2 nodes. A retrospective study was performed of all patients with clinical stage I (T1-2aN0) non-small cell lung cancer (American Joint Committee on Cancer, 7th edition) by positron emission tomography-computed tomography at our institution from 2003 to 2011, with subsequent surgical resection and lymph node staging. Findings on positron emission tomography-computed tomography were compared to pathologic nodal involvement to determine the negative predictive value of positron emission tomography-computed tomography for the detection of N1 nodal disease. An analysis was conducted to identify predictors of occult spread. A total of 105 patients with clinical stage I non-small cell lung cancer were included in this study, of which 8 (7.6%) patients were found to have occult N1 metastasis on pathologic review yielding a negative predictive value for N1 disease of 92.4%. No patients had occult mediastinal nodes. The negative predictive value for positron emission tomography-computed tomography in patients with clinical stage T1 versus T2 tumors was 72 (96%) of 75 versus 25 (83%) of 30, respectively ( P = .03), and for peripheral versus central tumor location was 77 (98%) of 78 versus 20 (74%) of 27, respectively ( P = .0001). The negative predictive values for peripheral T1 and T2 tumors were 98% and 100%, respectively; while for central T1 and T2 tumors, the rates were 85% and 64%, respectively. Occult lymph node involvement was not associated with primary tumor maximum standard uptake value, histology, grade, or interval between positron emission tomography-computed tomography and surgery. Our results support pathologic assessment of N1 lymph nodes in patients with stage Inon-small cell lung cancer considered for stereotactic body radiotherapy, with the greatest benefit in patients with central and T2 tumors. Diagnostic evaluation with endoscopic bronchial ultrasound should be considered in the evaluation of stereotactic body radiotherapy candidates.

Postmortem whole-body computed tomography angiography visualizing vascular rupture in a case of fatal car crash.

PubMed

Flach, Patricia M; Ross, Steffen G; Bolliger, Stephan A; Preiss, Ulrich S; Thali, Michael J; Spendlove, Danny

2010-01-01

In addition to the increasingly significant role of multislice computed tomography in forensic pathology, the performance of whole-body computed tomography angiography provides outstanding results. In this case, we were able to detect multiple injuries of the parenchymal organs in the upper abdomen as well as lesions of the brain parenchyma and vasculature of the neck. The radiologic findings showed complete concordance with the autopsy and even supplemented the autopsy findings in areas that are difficult to access via a manual dissection (such as the vasculature of the neck). This case shows how minimally invasive computed tomography angiography can serve as an invaluable adjunct to the classic autopsy procedure.

Computed tomography in the evaluation of Crohn disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldberg, H.I.; Gore, R.M.; Margulis, A.R.

1983-02-01

The abdominal and pelvic computed tomographic examinations in 28 patients with Crohn disease were analyzed and correlated with conventional barium studies, sinograms, and surgical findings. Mucosal abnormalities such as aphthous lesions, pseudopolyps, and ulcerations were only imaged by conventional techniques. Computed tomography proved superior in demonstrating the mural, serosal, and mesenteric abnormalities such as bowel wall thickening (82%), fibrofatty proliferation of mesenteric fat (39%), mesenteric abscess (25%), inflammatory reaction of the mesentery (14%), and mesenteric lymphadenopathy (18%). Computed tomography was most useful clinically in defining the nature of mass effects, separation, or displacement of small bowel segments seen on smallmore » bowel series. Although conventional barium studies remain the initial diagnostic procedure in evaluating Crohn disease, computed tomography can be a useful adjunct in resolving difficult clinical and radiologic diagnostic problems.« less

Coronary artery stenosis detection with holographic display of 3D angiograms

NASA Astrophysics Data System (ADS)

Ritman, Erik L.; Schwanke, Todd D.; Simari, Robert D.; Schwartz, Robert S.; Thomas, Paul J.

1995-05-01

The objective of this study was to establish the accuracy of an holographic display approach for detection of stenoses in coronary arteries. The rationale for using an holographic display approach is that multiple angles of view of the coronary arteriogram are provided by a single 'x-ray'-like film, backlit by a special light box. This should be more convenient in that the viewer does not have to page back and forth through a cine angiogram to obtain the multiple angles of view. The method used to test this technique involved viewing 100 3D coronary angiograms. These images were generated from the 3D angiographic images of nine normal coronary arterial trees generated with the Dynamic Spatial Reconstructor (DSR) fast CT scanner. Using our image processing programs, the image of the coronary artery lumen was locally 'narrowed' by an amount and length and at a location determined by a random look-up table. Two independent, blinded, experienced angiographers viewed the holographic displays of these angiograms and recorded their confidence about the presence, location, and severity of the stenoses. This procedure evaluates the sensitivity and specificity of the detection of coronary artery stenoses as a function of the severity, size, and location along the arteries.

The efficacy of preoperative positron emission tomography-computed tomography (PET-CT) for detection of lymph node metastasis in cervical and endometrial cancer: clinical and pathological factors influencing it.

PubMed

Nogami, Yuya; Banno, Kouji; Irie, Haruko; Iida, Miho; Kisu, Iori; Masugi, Yohei; Tanaka, Kyoko; Tominaga, Eiichiro; Okuda, Shigeo; Murakami, Koji; Aoki, Daisuke

2015-01-01

We studied the diagnostic performance of (18)F-fluoro-2-deoxy-d-glucose-positron emission tomography/computed tomography in cervical and endometrial cancers with particular focus on lymph node metastases. Seventy patients with cervical cancer and 53 with endometrial cancer were imaged with (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography before lymphadenectomy. We evaluated the diagnostic performance of (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography using the final pathological diagnoses as the golden standard. We calculated the sensitivity, specificity, positive predictive value and negative predictive value of (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography. In cervical cancer, the results evaluated by cases were 33.3, 92.7, 55.6 and 83.6%, respectively. When evaluated by the area of lymph nodes, the results were 30.6, 98.9, 55.0 and 97.0%, respectively. As for endometrial cancer, the results evaluated by cases were 50.0, 93.9, 40.0 and 95.8%, and by area of lymph nodes, 45.0, 99.4, 64.3 and 98.5%, respectively. The limitation of the efficacy was found out by analyzing it by the region of the lymph node, the size of metastatic node, the historical type of tumor in cervical cancer and the prevalence of lymph node metastasis. The efficacy of positron emission tomography/computed tomography regarding the detection of lymph node metastasis in cervical and endometrial cancer is not established and has limitations associated with the region of the lymph node, the size of metastasis lesion in lymph node and the pathological type of primary tumor. The indication for the imaging and the interpretation of the results requires consideration for each case by the pretest probability based on the information obtained preoperatively. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Diagnostic ability of computed tomography using DentaScan software in endodontics: case reports.

PubMed

Siotia, Jaya; Gupta, Sunil K; Acharya, Shashi R; Saraswathi, Vidya

2011-01-01

Radiographic examination is essential in diagnosis and treatment planning in endodontics. Conventional radiographs depict structures in two dimensions only. The ability to assess the area of interest in three dimensions is advantageous. Computed tomography is an imaging technique which produces three-dimensional images of an object by taking a series of two-dimensional sectional X-ray images. DentaScan is a computed tomography software program that allows the mandible and maxilla to be imaged in three planes: axial, panoramic, and cross-sectional. As computed tomography is used in endodontics, DentaScan can play a wider role in endodontic diagnosis. It provides valuable information in the assessment of the morphology of the root canal, diagnosis of root fractures, internal and external resorptions, pre-operative assessment of anatomic structures etc. The aim of this article is to explore the clinical usefulness of computed tomography and DentaScan in endodontic diagnosis, through a series of four cases of different endodontic problems.

Recent Scientific Evidence and Technical Developments in Cardiovascular Computed Tomography.

PubMed

Marcus, Roy; Ruff, Christer; Burgstahler, Christof; Notohamiprodjo, Mike; Nikolaou, Konstantin; Geisler, Tobias; Schroeder, Stephen; Bamberg, Fabian

2016-05-01

In recent years, coronary computed tomography angiography has become an increasingly safe and noninvasive modality for the evaluation of the anatomical structure of the coronary artery tree with diagnostic benefits especially in patients with a low-to-intermediate pretest probability of disease. Currently, increasing evidence from large randomized diagnostic trials is accumulating on the diagnostic impact of computed tomography angiography for the management of patients with acute and stable chest pain syndrome. At the same time, technical advances have substantially reduced adverse effects and limiting factors, such as radiation exposure, the amount of iodinated contrast agent, and scanning time, rendering the technique appropriate for broader clinical applications. In this work, we review the latest developments in computed tomography technology and describe the scientific evidence on the use of cardiac computed tomography angiography to evaluate patients with acute and stable chest pain syndrome. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Routine Clinical Quantitative Rest Stress Myocardial Perfusion for Managing Coronary Artery Disease: Clinical Relevance of Test-Retest Variability.

PubMed

Kitkungvan, Danai; Johnson, Nils P; Roby, Amanda E; Patel, Monika B; Kirkeeide, Richard; Gould, K Lance

2017-05-01

Positron emission tomography (PET) quantifies stress myocardial perfusion (in cc/min/g) and coronary flow reserve to guide noninvasively the management of coronary artery disease. This study determined their test-retest precision within minutes and daily biological variability essential for bounding clinical decision-making or risk stratification based on low flow ischemic thresholds or follow-up changes. Randomized trials of fractional flow reserve-guided percutaneous coronary interventions established an objective, quantitative, outcomes-driven standard of physiological stenosis severity. However, pressure-derived fractional flow reserve requires invasive coronary angiogram and was originally validated by comparison to noninvasive PET. The time course and test-retest precision of serial quantitative rest-rest and stress-stress global myocardial perfusion by PET within minutes and days apart in the same patient were compared in 120 volunteers undergoing serial 708 quantitative PET perfusion scans using rubidium 82 (Rb-82) and dipyridamole stress with a 2-dimensional PET-computed tomography scanner (GE DST 16) and University of Texas HeartSee software with our validated perfusion model. Test-retest methodological precision (coefficient of variance) for serial quantitative global myocardial perfusion minutes apart is ±10% (mean ΔSD at rest ±0.09, at stress ±0.23 cc/min/g) and for days apart is ±21% (mean ΔSD at rest ±0.2, at stress ±0.46 cc/min/g) reflecting added biological variability. Global myocardial perfusion at 8 min after 4-min dipyridamole infusion is 10% higher than at standard 4 min after dipyridamole. Test-retest methodological precision of global PET myocardial perfusion by serial rest or stress PET minutes apart is ±10%. Day-to-different-day biological plus methodological variability is ±21%, thereby establishing boundaries of variability on physiological severity to guide or follow coronary artery disease management. Maximum stress increases perfusion and coronary flow reserve, thereby reducing potentially falsely low values mimicking ischemia. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Dental application of novel finite element analysis software for three-dimensional finite element modeling of a dentulous mandible from its computed tomography images.

PubMed

Nakamura, Keiko; Tajima, Kiyoshi; Chen, Ker-Kong; Nagamatsu, Yuki; Kakigawa, Hiroshi; Masumi, Shin-ich

2013-12-01

This study focused on the application of novel finite-element analysis software for constructing a finite-element model from the computed tomography data of a human dentulous mandible. The finite-element model is necessary for evaluating the mechanical response of the alveolar part of the mandible, resulting from occlusal force applied to the teeth during biting. Commercially available patient-specific general computed tomography-based finite-element analysis software was solely applied to the finite-element analysis for the extraction of computed tomography data. The mandibular bone with teeth was extracted from the original images. Both the enamel and the dentin were extracted after image processing, and the periodontal ligament was created from the segmented dentin. The constructed finite-element model was reasonably accurate using a total of 234,644 nodes and 1,268,784 tetrahedral and 40,665 shell elements. The elastic moduli of the heterogeneous mandibular bone were determined from the bone density data of the computed tomography images. The results suggested that the software applied in this study is both useful and powerful for creating a more accurate three-dimensional finite-element model of a dentulous mandible from the computed tomography data without the need for any other software.

Rib Radiography versus Chest Computed Tomography in the Diagnosis of Rib Fractures.

PubMed

Sano, Atsushi

2018-05-01

 The accurate diagnosis of rib fractures is important in chest trauma. Diagnostic images following chest trauma are usually obtained via chest X-ray, chest computed tomography, or rib radiography. This study evaluated the diagnostic characteristics of rib radiography and chest computed tomography.  Seventy-five rib fracture patients who underwent both chest computed tomography and rib radiography between April 2008 and December 2013 were included. Rib radiographs, centered on the site of pain, were taken from two directions. Chest computed tomography was performed using a 16-row multidetector scanner with 5-mm slice-pitch without overlap, and axial images were visualized in a bone window.  In total, 217 rib fractures were diagnosed in 75 patients. Rib radiography missed 43 rib fractures in 24 patients. The causes were overlap with organs in 15 cases, trivial fractures in 21 cases, and injury outside the imaging range in 7 cases. Left lower rib fractures were often missed due to overlap with the heart, while middle and lower rib fractures were frequently not diagnosed due to overlap with abdominal organs. Computed tomography missed 21 rib fractures in 17 patients. The causes were horizontal fractures in 10 cases, trivial fractures in 9 cases, and insufficient breath holding in 1 case.  In rib radiography, overlap with organs and fractures outside the imaging range were characteristic reasons for missed diagnoses. In chest computed tomography, horizontal rib fractures and insufficient breath holding were often responsible. We should take these challenges into account when diagnosing rib fractures. Georg Thieme Verlag KG Stuttgart · New York.

64 slice-coronary computed tomography sensitivity and specificity in the evaluation of coronary artery bypass graft stenosis: A meta-analysis.

PubMed

Barbero, Umberto; Iannaccone, Mario; d'Ascenzo, Fabrizio; Barbero, Cristina; Mohamed, Abdirashid; Annone, Umberto; Benedetto, Sara; Celentani, Dario; Gagliardi, Marco; Moretti, Claudio; Gaita, Fiorenzo

2016-08-01

A non-invasive approach to define grafts patency and stenosis in the follow-up of coronary artery bypass graft (CABG) patients may be an interesting alternative to coronary angiography. 64-slice-coronary computed tomography is nowadays a diffused non-invasive method that permits an accurate evaluation of coronary stenosis, due to a high temporal and spatial resolution. However, its sensitivity and specificity in CABG evaluation has to be clearly defined, since published studies used different protocols and scanners. We collected all studies investigating patients with stable symptoms and previous CABG and reporting the comparison between diagnostic performances of invasive coronary angiography and 64-slice-coronary computed tomography. As a result, sensitivity and specificity of 64-slice-coronary computed tomography for CABG occlusion were 0.99 (95% CI 0.97-1.00) and 0.99 (95% CI: 0.99-1.00) with an area under the curve (AUC) of 0.99. 64-slice-coronary computed tomography sensitivity and specificity for the presence of any CABG stenosis >50% were 0.98 (95% CI: 0.97-0.99) and 0.98 (95% CI: 0.96-0.98), while AUC was 0.99. At meta-regression, neither the age nor the time from graft implantation had effect on sensitivity and specificity of 64-slice-coronary computed tomography detection of significant CABG stenosis or occlusion. In conclusion 64-slice-coronary computed tomography confirmed its high sensitivity and specificity in CABG stenosis or occlusion evaluation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Quadruple Axis Neutron Computed Tomography

NASA Astrophysics Data System (ADS)

Schillinger, Burkhard; Bausenwein, Dominik

Neutron computed tomography takes more time for a full tomography than X-rays or Synchrotron radiation, because the source intensity is limited. Most neutron imaging detectors have a square field of view, so if tomography of elongated, narrow samples, e.g. fuel rods, sword blades is recorded, much of the detector area is wasted. Using multiple rotation axes, several samples can be placed inside the field of view, and multiple tomographies can be recorded at the same time by later splitting the recorded images into separate tomography data sets. We describe a new multiple-axis setup using four independent miniaturized rotation tables.

Impact of Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) and Positron Emission Tomography/Computed Tomography (PET/CT) in the Diagnosis of Traumatic Brain Injury (TBI): Case Report.

PubMed

Molina-Vicenty, Irma L; Santiago-Sánchez, Michelaldemar; Vélez-Miró, Iván; Motta-Valencia, Keryl

2016-09-01

Traumatic brain injury (TBI) is defined as damage to the brain resulting from an external force. TBI, a global leading cause of death and disability, is associated with serious social, economic, and health problems. In cases of mild-to-moderate brain damage, conventional anatomical imaging modalities may or may not detect the cascade of metabolic changes that have occurred or are occurring at the intracellular level. Functional nuclear medicine imaging and neurophysiological parameters can be used to characterize brain damage, as the former provides direct visualization of brain function, even in the absence of overt behavioral manifestations or anatomical findings. We report the case of a 30-year-old Hispanic male veteran who, after 2 traumatic brain injury events, developed cognitive and neuropsychological problems with no clear etiology in the presence of negative computed tomography (CT) findings.

Computational Fluid Dynamics modeling of contrast transport in basilar aneurysms following flow-altering surgeries.

PubMed

Vali, Alireza; Abla, Adib A; Lawton, Michael T; Saloner, David; Rayz, Vitaliy L

2017-01-04

In vivo measurement of blood velocity fields and flow descriptors remains challenging due to image artifacts and limited resolution of current imaging methods; however, in vivo imaging data can be used to inform and validate patient-specific computational fluid dynamics (CFD) models. Image-based CFD can be particularly useful for planning surgical interventions in complicated cases such as fusiform aneurysms of the basilar artery, where it is crucial to alter pathological hemodynamics while preserving flow to the distal vasculature. In this study, patient-specific CFD modeling was conducted for two basilar aneurysm patients considered for surgical treatment. In addition to velocity fields, transport of contrast agent was simulated for the preoperative and postoperative conditions using two approaches. The transport of a virtual contrast passively following the flow streamlines was simulated to predict post-surgical flow regions prone to thrombus deposition. In addition, the transport of a mixture of blood with an iodine-based contrast agent was modeled to compare and verify the CFD results with X-ray angiograms. The CFD-predicted patterns of contrast flow were qualitatively compared to in vivo X-ray angiograms acquired before and after the intervention. The results suggest that the mixture modeling approach, accounting for the flow rates and properties of the contrast injection, is in better agreement with the X-ray angiography data. The virtual contrast modeling assessed the residence time based on flow patterns unaffected by the injection procedure, which makes the virtual contrast modeling approach better suited for prediction of thrombus deposition, which is not limited to the peri-procedural state. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of clinical presentation and pretest likelihood on the relation between calcium score and computed tomographic coronary angiography.

PubMed

van Werkhoven, Jacob M; de Boer, Stephanie M; Schuijf, Joanne D; Cademartiri, Filippo; Maffei, Erica; Jukema, J Wouter; Boogers, Mark J; Kroft, Lucia J; de Roos, Albert; Bax, Jeroen J

2010-12-15

The purpose of the present study was to assess the impact of clinical presentation and pretest likelihood on the relation between coronary calcium score (CCS) and computed tomographic coronary angiography (CTA) to determine the role of CCS as a gatekeeper to CTA in patients presenting with chest pain. In 576 patients with suspected coronary artery disease (CAD), CCS and CTA were performed. CCS was categorized as 0, 1 to 400, and >400. On CT angiogram the presence of significant CAD (≥50% luminal narrowing) was determined. Significant CAD was observed in 14 of 242 patients (5.8%) with CCS 0, in 94 of 260 patients (36.2%) with CCS 1 to 400, and in 60 of 74 patients (81.1%) with CCS >400. In patients with CCS 0, prevalence of significant CAD increased from 3.9% to 4.1% and 14.3% in nonanginal, atypical, and typical chest pain, respectively, and from 3.4% to 3.9% and 27.3% with a low, intermediate, and high pretest likelihood, respectively. In patients with CCS 1 to 400, prevalence of significant CAD increased from 27.4% to 34.7% and 51.7% in nonanginal, atypical, and typical chest pain, respectively, and from 15.4% to 35.6% and 50% in low, intermediate, and high pretest likelihood, respectively. In patients with CCS >400, prevalence of significant CAD on CT angiogram remained high (>72%) regardless of clinical presentation and pretest likelihood. In conclusion, the relation between CCS and CTA is influenced by clinical presentation and pretest likelihood. These factors should be taken into account when using CCS as a gatekeeper for CTA. Copyright © 2010 Elsevier Inc. All rights reserved.

Advanced Computed-Tomography Inspection System

NASA Technical Reports Server (NTRS)

Harris, Lowell D.; Gupta, Nand K.; Smith, Charles R.; Bernardi, Richard T.; Moore, John F.; Hediger, Lisa

1993-01-01

Advanced Computed Tomography Inspection System (ACTIS) is computed-tomography x-ray apparatus revealing internal structures of objects in wide range of sizes and materials. Three x-ray sources and adjustable scan geometry gives system unprecedented versatility. Gantry contains translation and rotation mechanisms scanning x-ray beam through object inspected. Distance between source and detector towers varied to suit object. System used in such diverse applications as development of new materials, refinement of manufacturing processes, and inspection of components.

Usefulness of Tc99m-mebrofenin Hepatobiliary Scintigraphy and Single Photon Emission Computed Tomography/Computed Tomography in the Diagnosis of Bronchobiliary Fistula.

PubMed

Parghane, Rahul Vithalrao; Phulsunga, Rohit Kumar; Gupta, Rajesh; Basher, Rajender Kumar; Bhattacharya, Anish; Mittal, Bhagwant Rai

2017-01-01

Bronchobiliary fistula (BBF), a rare complication of liver disease, is an abnormal communication between the biliary tract and bronchial tree. BBF may occur as a consequence of local liver infections such as hydatid or amebic disease, pyogenic liver abscess or trauma to the liver, obstruction of biliary tract, and tumor. As such management of liver disease with BBF is very difficult and often associated with a high rate of morbidity and mortality. Therefore, timely diagnosis of BBF is imperative. Hepatobiliary scintigraphy along with hybrid single photon emission computed tomography/computed tomography using Tc99m-mebrofenin is a very useful noninvasive imaging modality, in the diagnosis of BBF.

Usefulness of Tc99m-mebrofenin Hepatobiliary Scintigraphy and Single Photon Emission Computed Tomography/Computed Tomography in the Diagnosis of Bronchobiliary Fistula

PubMed Central

Parghane, Rahul Vithalrao; Phulsunga, Rohit Kumar; Gupta, Rajesh; Basher, Rajender Kumar; Bhattacharya, Anish; Mittal, Bhagwant Rai

2017-01-01

Bronchobiliary fistula (BBF), a rare complication of liver disease, is an abnormal communication between the biliary tract and bronchial tree. BBF may occur as a consequence of local liver infections such as hydatid or amebic disease, pyogenic liver abscess or trauma to the liver, obstruction of biliary tract, and tumor. As such management of liver disease with BBF is very difficult and often associated with a high rate of morbidity and mortality. Therefore, timely diagnosis of BBF is imperative. Hepatobiliary scintigraphy along with hybrid single photon emission computed tomography/computed tomography using Tc99m-mebrofenin is a very useful noninvasive imaging modality, in the diagnosis of BBF. PMID:29033682

Weightbearing Computed Tomography of the Foot and Ankle: Emerging Technology Topical Review.

PubMed

Barg, Alexej; Bailey, Travis; Richter, Martinus; de Cesar Netto, Cesar; Lintz, François; Burssens, Arne; Phisitkul, Phinit; Hanrahan, Christopher J; Saltzman, Charles L

2018-03-01

In the last decade, cone-beam computed tomography technology with improved designs allowing flexible gantry movements has allowed both supine and standing weight-bearing imaging of the lower extremity. There is an increasing amount of literature describing the use of weightbearing computed tomography in patients with foot and ankle disorders. To date, there is no review article summarizing this imaging modality in the foot and ankle. Therefore, we performed a systematic literature review of relevant clinical studies targeting the use of weightbearing computed tomography in diagnosis of patients with foot and ankle disorders. Furthermore, this review aims to offer insight to those with interest in considering possible future research opportunities with use of this technology. Level V, expert opinion.

Evaluating the risk of appendiceal perforation when using ultrasound as the initial diagnostic imaging modality in children with suspected appendicitis.

PubMed

Alerhand, Stephen; Meltzer, James; Tay, Ee Tein

2017-08-01

Ultrasound scan has gained attention for diagnosing appendicitis due to its avoidance of ionizing radiation. However, studies show that ultrasound scan carries inferior sensitivity to computed tomography scan. A non-diagnostic ultrasound scan could increase the time to diagnosis and appendicectomy, particularly if follow-up computed tomography scan is needed. Some studies suggest that delaying appendicectomy increases the risk of perforation. To investigate the risk of appendiceal perforation when using ultrasound scan as the initial diagnostic imaging modality in children with suspected appendicitis. We retrospectively reviewed 1411 charts of children ≤17 years old diagnosed with appendicitis at two urban academic medical centers. Patients who underwent ultrasound scan first were compared to those who underwent computed tomography scan first. In the sub-group analysis, patients who only received ultrasound scan were compared to those who received initial ultrasound scan followed by computed tomography scan. Main outcome measures were appendiceal perforation rate and time from triage to appendicectomy. In 720 children eligible for analysis, there was no significant difference in perforation rate between those who had initial ultrasound scan and those who had initial computed tomography scan (7.3% vs. 8.9%, p = 0.44), nor in those who had ultrasound scan only and those who had initial ultrasound scan followed by computed tomography scan (8.0% vs. 5.6%, p = 0.42). Those patients who had ultrasound scan first had a shorter triage-to-incision time than those who had computed tomography scan first (9.2 (IQR: 5.9, 14.0) vs. 10.2 (IQR: 7.3, 14.3) hours, p = 0.03), whereas those who had ultrasound scan followed by computed tomography scan took longer than those who had ultrasound scan only (7.8 (IQR: 5.3, 11.6) vs. 15.1 (IQR: 10.6, 20.6), p < 0.001). Children < 12 years old receiving ultrasound scan first had lower perforation rate (p = 0.01) and shorter triage-to-incision time (p = 0.003). Children with suspected appendicitis receiving ultrasound scan as the initial diagnostic imaging modality do not have increased risk of perforation compared to those receiving computed tomography scan first. We recommend that children <12 years of age receive ultrasound scan first.

Neural networks for calibration tomography

NASA Technical Reports Server (NTRS)

Decker, Arthur

1993-01-01

Artificial neural networks are suitable for performing pattern-to-pattern calibrations. These calibrations are potentially useful for facilities operations in aeronautics, the control of optical alignment, and the like. Computed tomography is compared with neural net calibration tomography for estimating density from its x-ray transform. X-ray transforms are measured, for example, in diffuse-illumination, holographic interferometry of fluids. Computed tomography and neural net calibration tomography are shown to have comparable performance for a 10 degree viewing cone and 29 interferograms within that cone. The system of tomography discussed is proposed as a relevant test of neural networks and other parallel processors intended for using flow visualization data.

Use of cone beam computed tomography in implant dentistry: current concepts, indications and limitations for clinical practice and research.

PubMed

Bornstein, Michael M; Horner, Keith; Jacobs, Reinhilde

2017-02-01

Diagnostic radiology is an essential component of treatment planning in the field of implant dentistry. This narrative review will present current concepts for the use of cone beam computed tomography imaging, before and after implant placement, in daily clinical practice and research. Guidelines for the selection of three-dimensional imaging will be discussed, and limitations will be highlighted. Current concepts of radiation dose optimization, including novel imaging modalities using low-dose protocols, will be presented. For preoperative cross-sectional imaging, data are still not available which demonstrate that cone beam computed tomography results in fewer intraoperative complications such as nerve damage or bleeding incidents, or that implants inserted using preoperative cone beam computed tomography data sets for planning purposes will exhibit higher survival or success rates. The use of cone beam computed tomography following the insertion of dental implants should be restricted to specific postoperative complications, such as damage of neurovascular structures or postoperative infections in relation to the maxillary sinus. Regarding peri-implantitis, the diagnosis and severity of the disease should be evaluated primarily based on clinical parameters and on radiological findings based on periapical radiographs (two dimensional). The use of cone beam computed tomography scans in clinical research might not yield any evident beneficial effect for the patient included. As many of the cone beam computed tomography scans performed for research have no direct therapeutic consequence, dose optimization measures should be implemented by using appropriate exposure parameters and by reducing the field of view to the actual region of interest. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

How reliably can computed tomography predict thyroid invasion prior to laryngectomy?

PubMed

Harris, Andrew S; Passant, Carl D; Ingrams, Duncan R

2018-05-01

There is little evidence to support the removal of thyroid tissue during total laryngectomy. Although oncological control of the tumor is the priority, thyroidectomy can lead to hypothyroidism and hypoparathyroidism. This study aimed to test the usefulness of preoperative computed tomography in predicting histological invasion of the thyroid. Ambispective cohort study. All patients undergoing total laryngectomy for squamous cell carcinoma at one center from 2006 to 2016 were included. Data were recorded prospectively as part of the patients' standard care, but were collated retrospectively, giving this study an ambispective design. The histology report for thyroid invasion was taken as the gold standard. The computed tomography report was categorized by invasion of tumor into intralaryngeal, laryngeal cartilage involvement, and extralaryngeal tissues. Seventy-nine patients were included. Nine patients had thyroid involvement on histology, translating to an incidence of 11.29% in this population. The positive predictive value for cartilage involvement on computed tomography for thyroid invasion was 52.9% (95% confidence interval [CI]: 28.5%-76.1%) and the negative predictive value was 100% (95% CI: 92.7%-100%).The positive predictive value for extralaryngeal spread on computed tomography for thyroid involvement was 100% (95% CI: 62.9%-100%), and the negative predictive value was also 100% (95% CI: 93.5%-100%). This study has shown that preoperative computed tomography is an effective method of ruling out thyroid gland invasion. The absence of extralaryngeal spread on computed tomography has been shown to be the most useful finding, with a high negative predictive value and a narrow 95% CI. 4. Laryngoscope, 128:1099-1102, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Diverticular Disease of the Colon: News From Imaging.

PubMed

Flor, Nicola; Soldi, Simone; Zanchetta, Edoardo; Sbaraini, Sara; Pesapane, Filippo

2016-10-01

Different scenarios embrace computed tomography imaging and diverticula, including asymptomatic (diverticulosis) and symptomatic patients (acute diverticulitis, follow-up of acute diverticulitis, chronic diverticulitis). If the role of computed tomography is validated and widely supported by evidence in case of acute diverticulitis, this is not the case of patients in their follow-up for acute diverticulitis or with symptoms related to diverticula, but without acute inflammation. In these settings, computed tomography colonography is gaining consensus as the preferred radiologic test.

Plain X-ray, computed tomography and magnetic resonance imaging findings of telangiectatic osteosarcoma: a case report.

PubMed

Skiadas, Vasilios; Koutoulidis, Vasilios; Koureas, Andreas; Moulopoulos, Lia; Gouliamos, Athanasios

2009-09-16

An 18-year-old male patient presented with chronic nonspecific pain of three months located at his left proximal tibia. The patient was admitted to our department for plain X-ray, computed tomography and magnetic resonance imaging examination. Plain X-ray and computed tomography revealed a geographic lytic lesion at the medial aspect of the proximal tibia. Biopsy of the lesion showed telangiectatic osteosarcoma. Image findings of all modalities are presented.

Advances in equine computed tomography and use of contrast media.

PubMed

Puchalski, Sarah M

2012-12-01

Advances in equine computed tomography have been made as a result of improvements in software and hardware and an increasing body of knowledge. Contrast media can be administered intravascularly or intrathecally. Contrast media is useful to differentiate between tissues of similar density. Equine computed tomography can be used for many different clinical conditions, including lameness diagnosis, fracture identification and characterization, preoperative planning, and characterization of skull diseases. Copyright © 2012 Elsevier Inc. All rights reserved.

[The radiologist physician in major trauma evaluation].

PubMed

Motta-Ramírez, Gaspar Alberto

2016-01-01

Trauma is the most common cause of death in young adults. A multidisciplinary trauma team consists of at least a surgical team, an anesthesiology team, radiologic team, and an emergency department team. Recognize the integration of multidisciplinary medical team in managing the trauma patient and which must include the radiologist physician responsible for the institutional approach to the systematization of the trauma patient regarding any radiological and imaging study with emphasis on the FAST (del inglés, Focused Assessment with Sonography in Trauma)/USTA, Whole body computed tomography. Ultrasound is a cross-sectional method available for use in patients with major trauma. Whole-body multidetector computed tomography became the imaging modality of choice in the late 1990s. In patients with major trauma, examination FAST often is the initial imaging examination, extended to extraabdominal regions. Patients who have multitrauma from blunt mechanisms often require multiple diagnostic examinations, including Computed Tomography imaging of the torso as well as abdominopelvic Computed Tomography angiography. Multiphasic Whole-body trauma imaging is feasible, helps detect clinically relevant vascular injuries, and results in diagnostic image quality in the majority of patients. Computed Tomography has gained importance in the early diagnostic phase of trauma care in the emergency room. With a single continuous acquisition, whole-body computed tomography angiography is able to demonstrate all potentially injured organs, as well as vascular and bone structures, from the circle of Willis to the symphysis pubis.

Development of computational small animal models and their applications in preclinical imaging and therapy research.

PubMed

Xie, Tianwu; Zaidi, Habib

2016-01-01

The development of multimodality preclinical imaging techniques and the rapid growth of realistic computer simulation tools have promoted the construction and application of computational laboratory animal models in preclinical research. Since the early 1990s, over 120 realistic computational animal models have been reported in the literature and used as surrogates to characterize the anatomy of actual animals for the simulation of preclinical studies involving the use of bioluminescence tomography, fluorescence molecular tomography, positron emission tomography, single-photon emission computed tomography, microcomputed tomography, magnetic resonance imaging, and optical imaging. Other applications include electromagnetic field simulation, ionizing and nonionizing radiation dosimetry, and the development and evaluation of new methodologies for multimodality image coregistration, segmentation, and reconstruction of small animal images. This paper provides a comprehensive review of the history and fundamental technologies used for the development of computational small animal models with a particular focus on their application in preclinical imaging as well as nonionizing and ionizing radiation dosimetry calculations. An overview of the overall process involved in the design of these models, including the fundamental elements used for the construction of different types of computational models, the identification of original anatomical data, the simulation tools used for solving various computational problems, and the applications of computational animal models in preclinical research. The authors also analyze the characteristics of categories of computational models (stylized, voxel-based, and boundary representation) and discuss the technical challenges faced at the present time as well as research needs in the future.

High-resolution PET [Positron Emission Tomography] for Medical Science Studies

DOE R&D Accomplishments Database

Budinger, T. F.; Derenzo, S. E.; Huesman, R. H.; Jagust, W. J.; Valk, P. E.

1989-09-01

One of the unexpected fruits of basic physics research and the computer revolution is the noninvasive imaging power available to today's physician. Technologies that were strictly the province of research scientists only a decade or two ago now serve as the foundations for such standard diagnostic tools as x-ray computer tomography (CT), magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), ultrasound, single photon emission computed tomography (SPECT), and positron emission tomography (PET). Furthermore, prompted by the needs of both the practicing physician and the clinical researcher, efforts to improve these technologies continue. This booklet endeavors to describe the advantages of achieving high resolution in PET imaging.

Use of Noncontrast Computed Tomography and Computed Tomographic Perfusion in Predicting Intracerebral Hemorrhage After Intravenous Alteplase Therapy.

PubMed

Batchelor, Connor; Pordeli, Pooneh; d'Esterre, Christopher D; Najm, Mohamed; Al-Ajlan, Fahad S; Boesen, Mari E; McDougall, Connor; Hur, Lisa; Fainardi, Enrico; Shankar, Jai Jai Shiva; Rubiera, Marta; Khaw, Alexander V; Hill, Michael D; Demchuk, Andrew M; Sajobi, Tolulope T; Goyal, Mayank; Lee, Ting-Yim; Aviv, Richard I; Menon, Bijoy K

2017-06-01

Intracerebral hemorrhage is a feared complication of intravenous alteplase therapy in patients with acute ischemic stroke. We explore the use of multimodal computed tomography in predicting this complication. All patients were administered intravenous alteplase with/without intra-arterial therapy. An age- and sex-matched case-control design with classic and conditional logistic regression techniques was chosen for analyses. Outcome was parenchymal hemorrhage on 24- to 48-hour imaging. Exposure variables were imaging (noncontrast computed tomography hypoattenuation degree, relative volume of very low cerebral blood volume, relative volume of cerebral blood flow ≤7 mL/min·per 100 g, relative volume of T max ≥16 s with all volumes standardized to z axis coverage, mean permeability surface area product values within T max ≥8 s volume, and mean permeability surface area product values within ipsilesional hemisphere) and clinical variables (NIHSS [National Institutes of Health Stroke Scale], onset to imaging time, baseline systolic blood pressure, blood glucose, serum creatinine, treatment type, and reperfusion status). One-hundred eighteen subjects (22 patients with parenchymal hemorrhage versus 96 without, median baseline NIHSS score of 15) were included in the final analysis. In multivariable regression, noncontrast computed tomography hypoattenuation grade ( P <0.006) and computerized tomography perfusion white matter relative volume of very low cerebral blood volume ( P =0.04) were the only significant variables associated with parenchymal hemorrhage on follow-up imaging (area under the curve, 0.73; 95% confidence interval, 0.63-0.83). Interrater reliability for noncontrast computed tomography hypoattenuation grade was moderate (κ=0.6). Baseline hypoattenuation on noncontrast computed tomography and very low cerebral blood volume on computerized tomography perfusion are associated with development of parenchymal hemorrhage in patients with acute ischemic stroke receiving intravenous alteplase. © 2017 American Heart Association, Inc.

Use of radiography, computed tomography and magnetic resonance imaging for evaluation of navicular syndrome in the horse.

PubMed

Widmer, W R; Buckwalter, K A; Fessler, J F; Hill, M A; VanSickle, D C; Ivancevich, S

2000-01-01

Radiographic evaluation of navicular syndrome is problematic because of its inconsistent correlation with clinical signs. Scintigraphy often yields false positive and false negative results and diagnostic ultrasound is of limited value. Therefore, we assessed the use of computed tomography and magnetic resonance imaging in a horse with clinical and radiographic signs of navicular syndrome. Cadaver specimens were examined with spiral computed tomographic and high-field magnetic resonance scanners and images were correlated with pathologic findings. Radiographic changes consisted of bony remodeling, which included altered synovial fossae, increased medullary opacity, cyst formation and shape change. These osseous changes were more striking and more numerous on computed tomographic and magnetic resonance images. They were most clearly defined with computed tomography. Many osseous changes seen with computed tomography and magnetic resonance imaging were not radiographically evident. Histologically confirmed soft tissue alterations of the deep digital flexor tendon, impar ligament and marrow were identified with magnetic resonance imaging, but not with conventional radiography. Because of their multiplanar capability and tomographic nature, computed tomography and magnetic resonance imaging surpass conventional radiography for navicular imaging, facilitating earlier, more accurate diagnosis. Current advances in imaging technology should make these imaging modalities available to equine practitioners in the future.

Quantitative Comparison of Virtual Monochromatic Images of Dual Energy Computed Tomography Systems: Beam Hardening Artifact Correction and Variance in Computed Tomography Numbers: A Phantom Study.

PubMed

Wu, Rongli; Watanabe, Yoshiyuki; Satoh, Kazuhiko; Liao, Yen-Peng; Takahashi, Hiroto; Tanaka, Hisashi; Tomiyama, Noriyuki

2018-05-21

The aim of this study was to quantitatively compare the reduction in beam hardening artifact (BHA) and variance in computed tomography (CT) numbers of virtual monochromatic energy (VME) images obtained with 3 dual-energy computed tomography (DECT) systems at a given radiation dose. Five different iodine concentrations were scanned using dual-energy and single-energy (120 kVp) modes. The BHA and CT number variance were evaluated. For higher iodine concentrations, 40 and 80 mgI/mL, BHA on VME imaging was significantly decreased when the energy was higher than 50 keV (P = 0.003) and 60 keV (P < 0.001) for GE, higher than 80 keV (P < 0.001) and 70 keV (P = 0.002) for Siemens, and higher than 40 keV (P < 0.001) and 60 keV (P < 0.001) for Toshiba, compared with single-energy CT imaging. Virtual monochromatic energy imaging can decrease BHA and improve CT number accuracy in different dual-energy computed tomography systems, depending on energy levels and iodine concentrations.

Virtopsy: postmortem imaging of laryngeal foreign bodies.

PubMed

Oesterhelweg, Lars; Bolliger, Stephan A; Thali, Michael J; Ross, Steffen

2009-05-01

Death from corpora aliena in the larynx is a well-known entity in forensic pathology. The correct diagnosis of this cause of death is difficult without an autopsy, and misdiagnoses by external examination alone are common. To determine the postmortem usefulness of modern imaging techniques in the diagnosis of foreign bodies in the larynx, multislice computed tomography, magnetic resonance imaging, and postmortem full-body computed tomography-angiography were performed. Three decedents with a suspected foreign body in the larynx underwent the 3 different imaging techniques before medicolegal autopsy. Multislice computed tomography has a high diagnostic value in the noninvasive localization of a foreign body and abnormalities in the larynx. The differentiation between neoplasm or soft foreign bodies (eg, food) is possible, but difficult, by unenhanced multislice computed tomography. By magnetic resonance imaging, the discrimination of the soft tissue structures and soft foreign bodies is much easier. In addition to the postmortem multislice computed tomography, the combination with postmortem angiography will increase the diagnostic value. Postmortem, cross-sectional imaging methods are highly valuable procedures for the noninvasive detection of corpora aliena in the larynx.

Isolated benign cerebral vasculitis or migrainous vasospasm?

PubMed Central

Serdaru, M; Chiras, J; Cujas, M; Lhermitte, F

1984-01-01

A 39-year-old woman experienced severe headache, epilepsy and rapidly progressive aphasia and hemianopia. Carotid angiograms displayed segmentary narrowing of intracranial arteries as previously described in benign cerebral vasculitis. Her superficial temporal artery was also involved, allowing a biopsy of the abnormal part of the vessel. Microscopical study of this artery was normal. A second carotid angiogram, 14 days later, showed normal intracranial arteries. These findings suggest arterial spasm rather than distal arteritis. Images PMID:6693916

Gunshot wounds to the thigh. Evaluation of vascular and subclinical vascular injuries.

PubMed

Payne, W K; Gabriel, R A; Massoud, R P

1995-01-01

A retrospective review of 173 patient charts, angiograms, surgical reports, and plain radiographs were performed for all patients admitted with gunshot wounds to the thigh from May 1988 to January 1991 at Martin Luther King, Jr. Hospital. A zonal classification of gunshot wounds to the thigh was created and defined to determine if a zonal classification was predictive of a positive angiogram. Associations and relationships of patients with vascular injury are presented.

Leg CT scan

MedlinePlus

CAT scan - leg; Computed axial tomography scan - leg; Computed tomography scan - leg; CT scan - leg ... CT scan makes detailed pictures of the body very quickly. The test may help look for: An abscess ...

Arm CT scan

MedlinePlus

CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... Healing problems or scar tissue following surgery A CT scan may also be used to guide a surgeon ...

USE OF COMPUTED TOMOGRAPHY FOR INVESTIGATION OF HEPATIC LIPIDOSIS IN CAPTIVE CHELONOIDIS CARBONARIA (SPIX, 1824).

PubMed

Marchiori, Adriano; da Silva, Ieverton Cleiton Correia; de Albuquerque Bonelli, Marília; de Albuquerque Zanotti, Luciana Carla Rameh; Siqueira, Daniel B; Zanotti, Alexandre Pinheiro; Costa, Fabiano Séllos

2015-06-01

Computed tomography is a sensitive and highly applicable technique for determining the degree of radiographic attenuation of the hepatic parenchyma. Radiodensity measurements of the liver can help in the diagnosis of hepatic lipidosis in humans and animals. The objective was to investigate the presence of hepatic lipidosis in captive red-footed tortoises (Chelonoidis carbonaria) using computed tomography. Computed tomography was performed in 10 male red-footed tortoises. Mean radiographic attenuation values for the hepatic parenchyma were 11.2±3.0 Hounsfield units (HU). Seven red-footed tortoises had values lower than 20 HU, which is compatible with C. carbonaria hepatic lipidosis. These results allowed an early diagnosis of the hepatic changes and suggested corrective measures regarding feeding and management protocols.

Multidetector Computed Tomography for Congenital Anomalies of the Aortic Arch: Vascular Rings.

PubMed

García-Guereta, Luis; García-Cerro, Estefanía; Bret-Zurita, Montserrat

2016-07-01

The development of multidetector computed tomography has triggered a revolution in the study of the aorta and other large vessels and has replaced angiography in the diagnosis of congenital anomalies of the aortic arch, particularly vascular rings. The major advantage of multidetector computed tomography is that it permits clear 3-dimensional assessment of not only vascular structures, but also airway and esophageal compression. The current update aims to summarize the embryonic development of the aortic arch and the developmental anomalies leading to vascular ring formation and to discuss the current diagnostic and therapeutic role of multidetector computed tomography in this field. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Comprehensive Digital Imaging Network Project At Georgetown University Hospital

NASA Astrophysics Data System (ADS)

Mun, Seong K.; Stauffer, Douglas; Zeman, Robert; Benson, Harold; Wang, Paul; Allman, Robert

1987-10-01

The radiology practice is going through rapid changes due to the introduction of state-of-the-art computed based technologies. For the last twenty years we have witnessed the introduction of many new medical diagnostic imaging systems such as x-ray computed tomo-graphy, digital subtraction angiography (DSA), computerized nuclear medicine, single pho-ton emission computed tomography (SPECT), positron emission tomography (PET) and more re-cently, computerized digital radiography and nuclear magnetic resonance imaging (MRI). Other than the imaging systems, there has been a steady introduction of computed based information systems for radiology departments and hospitals.

Utility of three-dimensional and multiplanar reformatted computed tomography for evaluation of pediatric congenital spine abnormalities.

PubMed

Newton, Peter O; Hahn, Gregory W; Fricka, Kevin B; Wenger, Dennis R

2002-04-15

A retrospective radiographic review of 31 patients with congenital spine abnormalities who underwent conventional radiography and advanced imaging studies was conducted. To analyze the utility of three-dimensional computed tomography with multiplanar reformatted images for congenital spine anomalies, as compared with plain radiographs and axial two-dimensional computed tomography imaging. Conventional radiographic imaging for congenital spine disorders often are difficult to interpret because of the patient's small size, the complexity of the disorder, a deformity not in the plane of the radiographs, superimposed structures, and difficulty in forming a mental three-dimensional image. Multiplanar reformatted and three-dimensional computed tomographic imaging offers many potential advantages for defining congenital spine anomalies including visualization of the deformity in any plane, from any angle, with the overlying structures subtracted. The imaging studies of patients who had undergone a three-dimensional computed tomography for congenital deformities of the spine between 1992 and 1998 were reviewed (31 cases). All plain radiographs and axial two-dimensional computed tomography images performed before the three-dimensional computed tomography were reviewed and the findings documented. This was repeated for the three-dimensional reconstructions and, when available, the multiplanar reformatted images (15 cases). In each case, the utility of the advanced imaging was graded as one of the following: Grade A (substantial new information obtained), Grade B (confirmatory with improved visualization and understanding of the deformity), and Grade C (no added useful information obtained). In 17 of 31 cases, the multiplanar reformatted and three-dimensional images allowed identification of unrecognized malformations. In nine additional cases, the advanced imaging was helpful in better visualizing and understanding previously identified deformities. In five cases, no new information was gained. The standard and curved multiplanar reformatted images were best for defining the occiput-C1-C2 anatomy and the extent of segmentation defects. The curved multiplanar reformatted images were especially helpful in keeping the spine from "coming in" and "going out" of the plane of the image when there was significant spine deformity in the sagittal or coronal plane. The three-dimensional reconstructions proved valuable in defining failures of formation. Advanced computed tomography imaging (three-dimensional computed tomography and curved/standard multiplanar reformatted images) allows better definition of congenital spine anomalies. More than 50% of the cases showed additional abnormalities not appreciated on plain radiographs or axial two-dimensional computed tomography images. Curved multiplanar reformatted images allowed imaging in the coronal and sagittal planes of the entire deformity.

Heart CT scan

MedlinePlus

... Computed tomography scan - heart; Calcium scoring; Multi-detector CT scan - heart; Electron beam computed tomography - heart; Agatston ... table that slides into the center of the CT scanner. You will lie on your back with ...

Evaluation of 3D airway imaging of obstructive sleep apnea with cone-beam computed tomography.

PubMed

Ogawa, Takumi; Enciso, Reyes; Memon, Ahmed; Mah, James K; Clark, Glenn T

2005-01-01

This study evaluates the use of cone-beam Computer Tomography (CT) for imaging the upper airway structure of Obstructive Sleep Apnea (OSA) patients. The total airway volume and the anteroposterior dimension of oropharyngeal airway showed significant group differences between OSA and gender-matched controls, so if we increase sample size these measurements may distinguish the two groups. We demonstrate the utility of diagnosis of anatomy with the 3D airway imaging with cone-beam Computed Tomography.

Cone beam computed tomography in Endodontics - a review.

PubMed

Patel, S; Durack, C; Abella, F; Shemesh, H; Roig, M; Lemberg, K

2015-01-01

Cone beam computed tomography (CBCT) produces undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a lower effective radiation dose than computed tomography. The aim of this paper is to: (i) review the current literature on the applications and limitations of CBCT; (ii) make recommendations for the use of CBCT in Endodontics; (iii) highlight areas of further research of CBCT in Endodontics. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

White Paper of the Society of Computed Body Tomography and Magnetic Resonance on Dual-Energy CT, Part 1: Technology and Terminology.

PubMed

Siegel, Marilyn J; Kaza, Ravi K; Bolus, David N; Boll, Daniel T; Rofsky, Neil M; De Cecco, Carlo N; Foley, W Dennis; Morgan, Desiree E; Schoepf, U Joseph; Sahani, Dushyant V; Shuman, William P; Vrtiska, Terri J; Yeh, Benjamin M; Berland, Lincoln L

This is the first of a series of 4 white papers that represent Expert Consensus Documents developed by the Society of Computed Body Tomography and Magnetic Resonance through its task force on dual-energy computed tomography (DECT). This article, part 1, describes the fundamentals of the physical basis for DECT and the technology of DECT and proposes uniform nomenclature to account for differences in proprietary terms among manufacturers.

[Cardiac computed tomography: new applications of an evolving technique].

PubMed

Martín, María; Corros, Cecilia; Calvo, Juan; Mesa, Alicia; García-Campos, Ana; Rodríguez, María Luisa; Barreiro, Manuel; Rozado, José; Colunga, Santiago; de la Hera, Jesús M; Morís, César; Luyando, Luis H

2015-01-01

During the last years we have witnessed an increasing development of imaging techniques applied in Cardiology. Among them, cardiac computed tomography is an emerging and evolving technique. With the current possibility of very low radiation studies, the applications have expanded and go further coronariography In the present article we review the technical developments of cardiac computed tomography and its new applications. Copyright © 2014 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

Plain X-ray, computed tomography and magnetic resonance imaging findings of telangiectatic osteosarcoma: a case report

PubMed Central

Koutoulidis, Vasilios; Koureas, Andreas; Moulopoulos, Lia; Gouliamos, Athanasios

2009-01-01

An 18-year-old male patient presented with chronic nonspecific pain of three months located at his left proximal tibia. The patient was admitted to our department for plain X-ray, computed tomography and magnetic resonance imaging examination. Plain X-ray and computed tomography revealed a geographic lytic lesion at the medial aspect of the proximal tibia. Biopsy of the lesion showed telangiectatic osteosarcoma. Image findings of all modalities are presented. PMID:19918488

Accuracy and Precision of Radioactivity Quantification in Nuclear Medicine Images

PubMed Central

Frey, Eric C.; Humm, John L.; Ljungberg, Michael

2012-01-01

The ability to reliably quantify activity in nuclear medicine has a number of increasingly important applications. Dosimetry for targeted therapy treatment planning or for approval of new imaging agents requires accurate estimation of the activity in organs, tumors, or voxels at several imaging time points. Another important application is the use of quantitative metrics derived from images, such as the standard uptake value commonly used in positron emission tomography (PET), to diagnose and follow treatment of tumors. These measures require quantification of organ or tumor activities in nuclear medicine images. However, there are a number of physical, patient, and technical factors that limit the quantitative reliability of nuclear medicine images. There have been a large number of improvements in instrumentation, including the development of hybrid single-photon emission computed tomography/computed tomography and PET/computed tomography systems, and reconstruction methods, including the use of statistical iterative reconstruction methods, which have substantially improved the ability to obtain reliable quantitative information from planar, single-photon emission computed tomography, and PET images. PMID:22475429

Management and decision-making process leading to coronary angiography and revascularization in octogenarians with coronary artery disease: Insights from a large single-center registry.

PubMed

Martin, Anne-Céline; Dumas, Florence; Spaulding, Christian; Manzo-Silberman, Stéphane

2015-05-01

Cardiovascular diseases remain the most common cause of death in older adults. Guidelines state that advanced age alone should not limit the use of invasive therapy. However, coronary angiograms and subsequent revascularization are often not carried out in octogenarians. The benefit/risk balance of an invasive strategy and the decision-making process are not clearly defined. The aim of the present study was to assess the decision-making process, and the in-hospital and long-term mortality based on the clinical presentation, the diagnostic approach (coronary angiogram or conservative) and the therapeutic management (revascularization or not). The present study was a single-center retrospective analysis. A total of 522 patients aged ≥80 years, with a diagnosis of coronary disease were included from 2003 to 2009. The mean age was 82 ± 2.6 years. A total of 195 of 522 (37%) presented with a ST segment elevation myocardial infarction (STEMI). A coronary angiogram was carried out in 316 patients (60.5%) and 71% were treated by percutaneous coronary revascularization. A total of 39.5% were considered ineligible for a coronary angiogram due to cardiological reasons or comorbidities. Excluding cardiogenic shock, overall in-hospital mortality was 4.9%. Clinical presentation strongly influenced both in-hospital and 6-month mortality rates (cardiogenic shock 20% and 28.7%, stable angina 1% and 4.1%, respectively, P < 0.001). Long-term mortality was reduced in the coronary angiography arm compared with the conservative group (14.3% vs 20.9%, P = 0.04) whether or not revascularization was carried out. In the present study, in octogenarians, long-term mortality was lower in the group of patients who underwent a coronary angiogram, regardless of revascularization. The selection process for coronary angiography and angioplasty was mostly influenced by the existence of age-associated comorbidities. Risk prediction models are required to reduce age-dependent biases. © 2014 Japan Geriatrics Society.

Meaning of Interior Tomography

PubMed Central

Wang, Ge; Yu, Hengyong

2013-01-01

The classic imaging geometry for computed tomography is for collection of un-truncated projections and reconstruction of a global image, with the Fourier transform as the theoretical foundation that is intrinsically non-local. Recently, interior tomography research has led to theoretically exact relationships between localities in the projection and image spaces and practically promising reconstruction algorithms. Initially, interior tomography was developed for x-ray computed tomography. Then, it has been elevated as a general imaging principle. Finally, a novel framework known as “omni-tomography” is being developed for grand fusion of multiple imaging modalities, allowing tomographic synchrony of diversified features. PMID:23912256

Correlation between Preoperative High Resolution Computed Tomography (CT) Findings with Surgical Findings in Chronic Otitis Media (COM) Squamosal Type.

PubMed

Karki, S; Pokharel, M; Suwal, S; Poudel, R

Background The exact role of High resolution computed tomography (HRCT) temporal bone in preoperative assessment of Chronic suppurative otitis media atticoantral disease still remains controversial. Objective To evaluate the role of high resolution computed tomography temporal bone in Chronic suppurative otitis media atticoantral disease and to compare preoperative computed tomographic findings with intra-operative findings. Method Prospective, analytical study conducted among 65 patients with chronic suppurative otitis media atticoantral disease in Department of Radiodiagnosis, Kathmandu University Dhulikhel Hospital between January 2015 to July 2016. The operative findings were compared with results of imaging. The parameters of comparison were erosion of ossicles, scutum, facial canal, lateral semicircular canal, sigmoid and tegmen plate along with extension of disease to sinus tympani and facial recess. Sensitivity, specificity, negative predictive value, positive predictive values were calculated. Result High resolution computed tomography temporal bone offered sensitivity (Se) and specificity (Sp) of 100% for visualization of sigmoid and tegmen plate erosion. The performance of HRCT in detecting malleus (Se=100%, Sp=95.23%), incus (Se=100%,Sp=80.48%) and stapes (Se=96.55%, Sp=71.42%) erosion was excellent. It offered precise information about facial canal erosion (Se=100%, Sp=75%), scutum erosion (Se=100%, Sp=96.87%) and extension of disease to facial recess and sinus tympani (Se=83.33%,Sp=100%). high resolution computed tomography showed specificity of 100% for lateral semicircular canal erosion (Sp=100%) but with low sensitivity (Se=53.84%). Conclusion The findings of high resolution computed tomography and intra-operative findings were well comparable except for lateral semicircular canal erosion. high resolution computed tomography temporal bone acts as a road map for surgeon to identify the extent of disease, plan for appropriate procedure that is required and prepare for potential complications that can be encountered during surgery.

CALIPSO: an interactive image analysis software package for desktop PACS workstations

NASA Astrophysics Data System (ADS)

Ratib, Osman M.; Huang, H. K.

1990-07-01

The purpose of this project is to develop a low cost workstation for quantitative analysis of multimodality images using a Macintosh II personal computer. In the current configuration the Macintosh operates as a stand alone workstation where images are imported either from a central PACS server through a standard Ethernet network or recorded through video digitizer board. The CALIPSO software developed contains a large variety ofbasic image display and manipulation tools. We focused our effort however on the design and implementation ofquantitative analysis methods that can be applied to images from different imaging modalities. Analysis modules currently implemented include geometric and densitometric volumes and ejection fraction calculation from radionuclide and cine-angiograms Fourier analysis ofcardiac wall motion vascular stenosis measurement color coded parametric display of regional flow distribution from dynamic coronary angiograms automatic analysis ofmyocardial distribution ofradiolabelled tracers from tomoscintigraphic images. Several of these analysis tools were selected because they use similar color coded andparametric display methods to communicate quantitative data extracted from the images. 1. Rationale and objectives of the project Developments of Picture Archiving and Communication Systems (PACS) in clinical environment allow physicians and radiologists to assess radiographic images directly through imaging workstations (''). This convenient access to the images is often limited by the number of workstations available due in part to their high cost. There is also an increasing need for quantitative analysis ofthe images. During thepast decade

Trails on 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Leading to Diagnosis of Testicular Adrenal Rest Tumor.

PubMed

Kashyap, Raghava

2018-01-01

Testicular adrenal rest tumors (TARTs) are secondary to hypertrophy of adrenal rest cells in the rete testis in settings of hypersecretion of androgens. We present a case of congenital adrenal hyperplasia with TART with clues to the diagnosis on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT). To the best of our knowledge, this is the first reported case on the role of 18 F-FDG PET/CT in TART.

Pleuroperitoneal Mesothelioma: A Rare Entity on 18F-FDG PET/CT

PubMed Central

Sahoo, Manas Kumar; Mukherjee, Anirban; Girish; Parida, Kumar; Agarwal, Krishan Kant; Bal, Chandrasekhar; Tripathi, Madhavi; Das, Chandan Jyoti; Shamim, Shamim Ahmed

2017-01-01

Pleuroperitoneal mesothelioma is an extremely rare entity. Only few cases are reported worldwide. We hereby represent a case of pleural mesothelioma referred for F-18-Fluorodeoxyglucose positron emission tomography/computed tomography for response evaluation. Diffuse F-18-Fluorodeoxyglucose avid peritoneal and omental thickening noted which subsequently turned out to be mesothelial involvement on peritoneal biopsy. This case demonstrates the role of F-18-Fluorodeoxyglucose positron emission tomography/computed tomography in detecting other sites of involvement in case of malignant mesothelioma. PMID:28242997

Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography in Disseminated Cryptococcosis.

PubMed

Tripathy, Sarthak; Parida, Girish Kumar; Roy, Shambo Guha; Singhal, Abhinav; Mallick, Saumya Ranjan; Tripathi, Madhavi; Shamim, Shamim Ahmed

2017-01-01

Disseminated cryptococcosis without pulmonary involvement is a very rare phenomenon. Patterns of organ involvement in cryptococcosis resemble various other infective conditions as well as malignant conditions on fluorodeoxyglucose positron emission tomography-computed tomography. We present a case of a 43-year-old male patient who had disseminated cryptococcosis. The rarity of the case being noninvolvement of lungs and meninges and resembling more like lymphoma due to the diffuse involvement of the lymph nodes on both sides of the diaphragm.

CT Perfusion of the Head

MedlinePlus

... News Physician Resources Professions Site Index A-Z CT Perfusion of the Head Computed tomography (CT) perfusion ... of CT Perfusion of the Head? What is CT Perfusion of the Head? Computed tomography (CT) perfusion ...

Quantification of pericardial effusions by echocardiography and computed tomography.

PubMed

Leibowitz, David; Perlman, Gidon; Planer, David; Gilon, Dan; Berman, Philip; Bogot, Naama

2011-01-15

Echocardiography is a well-accepted tool for the diagnosis and quantification of pericardial effusion (PEff). Given the increasing use of computed tomographic (CT) scanning, more PEffs are being initially diagnosed by computed tomography. No study has compared quantification of PEff by computed tomography and echocardiography. The objective of this study was to assess the accuracy of quantification of PEff by 2-dimensional echocardiography and computed tomography compared to the amount of pericardial fluid drained at pericardiocentesis. We retrospectively reviewed an institutional database to identify patients who underwent chest computed tomography and echocardiography before percutaneous pericardiocentesis with documentation of the amount of fluid withdrawn. Digital 2-dimensional echocardiographic and CT images were retrieved and quantification of PEff volume was performed by applying the formula for the volume of a prolate ellipse, π × 4/3 × maximal long-axis dimension/2 × maximal transverse dimension/2 × maximal anteroposterior dimension/2, to the pericardial sac and to the heart. Nineteen patients meeting study qualifications were entered into the study. The amount of PEff drained was 200 to 1,700 ml (mean 674 ± 340). Echocardiographically calculated pericardial effusion volume correlated relatively well with PEff volume (r = 0.73, p <0.001, mean difference -41 ± 225 ml). There was only moderate correlation between CT volume quantification and actual volume drained (r = 0.4, p = 0.004, mean difference 158 ± 379 ml). In conclusion, echocardiography appears a more accurate imaging technique than computed tomography in quantitative assessment of nonloculated PEffs and should continue to be the primary imaging in these patients. Copyright © 2011 Elsevier Inc. All rights reserved.

Development of computational small animal models and their applications in preclinical imaging and therapy research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Tianwu; Zaidi, Habib, E-mail: habib.zaidi@hcuge.ch; Geneva Neuroscience Center, Geneva University, Geneva CH-1205

The development of multimodality preclinical imaging techniques and the rapid growth of realistic computer simulation tools have promoted the construction and application of computational laboratory animal models in preclinical research. Since the early 1990s, over 120 realistic computational animal models have been reported in the literature and used as surrogates to characterize the anatomy of actual animals for the simulation of preclinical studies involving the use of bioluminescence tomography, fluorescence molecular tomography, positron emission tomography, single-photon emission computed tomography, microcomputed tomography, magnetic resonance imaging, and optical imaging. Other applications include electromagnetic field simulation, ionizing and nonionizing radiation dosimetry, and themore » development and evaluation of new methodologies for multimodality image coregistration, segmentation, and reconstruction of small animal images. This paper provides a comprehensive review of the history and fundamental technologies used for the development of computational small animal models with a particular focus on their application in preclinical imaging as well as nonionizing and ionizing radiation dosimetry calculations. An overview of the overall process involved in the design of these models, including the fundamental elements used for the construction of different types of computational models, the identification of original anatomical data, the simulation tools used for solving various computational problems, and the applications of computational animal models in preclinical research. The authors also analyze the characteristics of categories of computational models (stylized, voxel-based, and boundary representation) and discuss the technical challenges faced at the present time as well as research needs in the future.« less

[Computed tomography semiotics of osteonecrosis and sequestration in chronic hematogenic osteomyelitis].

PubMed

D'iachkova, G V; Mitina, Iu L

2007-01-01

Based on the data of computed tomography, radiography and densitometry in 39 patients the authors describe in detail the signs of osteonecrosis and sequestration of different localization and extension.

Pelvic CT scan

MedlinePlus

CAT scan - pelvis; Computed axial tomography scan - pelvis; Computed tomography scan - pelvis; CT scan - pelvis ... Risks of CT scans include: Being exposed to radiation Allergic reaction to contrast dye CT scans do expose you to more radiation ...

Lumbar spine CT scan

MedlinePlus

CAT scan - lumbar spine; Computed axial tomography scan - lumbar spine; Computed tomography scan - lumbar spine; CT - lower back ... CT scans rapidly makes detailed pictures of the lower back. The test may be used to look for: ...

Shoulder CT scan

MedlinePlus

CAT scan - shoulder; Computed axial tomography scan - shoulder; Computed tomography scan - shoulder; CT scan - shoulder ... Risks of CT scans include: Being exposed to radiation Allergic reaction to contrast dye Birth defect if done during pregnancy CT scans ...

SPECT/CT in imaging foot and ankle pathology-the demise of other coregistration techniques.

PubMed

Mohan, Hosahalli K; Gnanasegaran, Gopinath; Vijayanathan, Sanjay; Fogelman, Ignac

2010-01-01

Disorders of the ankle and foot are common and given the complex anatomy and function of the foot, they present a significant clinical challenge. Imaging plays a crucial role in the management of these patients, with multiple imaging options available to the clinician. The American College of radiology has set the appropriateness criteria for the use of the available investigating modalities in the management of foot and ankle pathologies. These are broadly classified into anatomical and functional imaging modalities. Recently, single-photon emission computed tomography and/or computed tomography scanners, which can elegantly combine functional and anatomical images have been introduced, promising an exciting and important development. This review describes our clinical experience with single-photon emission computed tomography and/or computed tomography and discusses potential applications of these techniques.

Comparison of radiological and morphologic assessments of myocardial bridges.

PubMed

Ercakmak, Burcu; Bulut, Elif; Hayran, Mutlu; Kaymaz, Figen; Bilgin, Selma; Hazirolan, Tuncay; Bayramoglu, Alp; Erbil, Mine

2015-09-01

In this study we aimed to compare the findings of coronary dual-source computed tomography angiography of myocardial bridges with cadaveric dissections. Forty-one isolated, non-damaged fresh sheep hearts were used in this study. Myocardial bridges of the anterior interventricular branch of the left coronary artery were demonstrated and analyzed by a coronary dual-source computed tomography angiography. Dissections along the left anterior interventricular branch of the left coronary artery were performed by using Zeiss OPMI pico microscope and the length of the bridges were measured. The depths of the myocardial bridges were measured from the stained sections by using the light microscope (Leica DM 6000B). MBs were found in all 41 hearts (100%) during dissections. Dual-source computed tomography angiography successfully detected 87.8% (36 of the 41 hearts) of the myocardial bridges measured on left anterior interventricular branch of left coronary artery. The lengths of the myocardial bridges were found 5-40 and 8-50 mm with dissection and dual-source computed tomography angiography, respectively. And the depths were found 0.7-4.5 mm by dual-source computed tomography angiography and 0.745-4.632 mm morphologically. Comparison of the mean values of the lengths showed statistically significantly higher values (22.0 ± 8.5, 17.7 ± 7.7 mm, p = 0.003) for the dissections. Radiological assessment also effectively discriminated complete bridges from incomplete ones. Our study showed that coronary computed tomography angiography is reliable in evaluating the presence and depth of myocardial bridges.

Sinus CT scan

MedlinePlus

CAT scan - sinus; Computed axial tomography scan - sinus; Computed tomography scan - sinus; CT scan - sinus ... Risks for a CT scan includes: Being exposed to radiation Allergic reaction to contrast dye CT scans expose you to more radiation than regular ...

Brain PET scan

MedlinePlus

... tissues are working. Other imaging tests, such as magnetic resonance imaging ( MRI ) and computed tomography ( CT ) scans only reveal ... M, Hellwig S, Kloppel S, Weiller C. Functional neuroimaging: functional magnetic resonance imaging, positron emission tomography, and single-photon emission computed ...

Chemoembolization for Hepatocellular Carcinoma Supplied by a Lumbar Artery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Han Myun, E-mail: seoul49@naver.com; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Woo, Sungmin, E-mail: j-crew7@hotmail.com

PurposeTo describe the radiologic findings and imaging response of hepatocellular carcinoma (HCC) supplied by the lumbar artery.MethodsBetween April 2004 and December 2012, we encountered HCC supplied by a lumbar artery in 21 patients. Two investigators retrospectively reviewed clinical and radiological findings of HCC supplied by the lumbar artery using computed tomography (CT) scans and digital subtraction angiograms.ResultsPatients had received 1–27 sessions of previous chemoembolization procedures (mean 7.7 sessions, median 4 sessions). Mean tumor size was 5.3 cm. The locations of HCC supplied by lumbar artery were the bare area (n = 14, 67 %) and segment VI (n = 7, 33 %). Tumor-feeding arteries arose from themore » main lumbar artery (n = 7), proximal anterior division (n = 4), and distal anterior division (n = 14). In 20 patients, selective chemoembolization through the tumor-feeding arteries of the lumbar artery was achieved. In 1 patient, nonselective embolization at the main lumbar artery was performed. There was no complication such as skin necrosis or paralysis. On the first follow-up enhanced CT scan, target tumors fed by the lumbar artery showed complete response (n = 6), partial response (n = 4), stable disease (n = 3), and progressive disease (n = 8), but overall tumor response was partial response (n = 1) and progressive disease (n = 20).ConclusionWhen HCC is located in the inferior tip or bare area of the liver, a lumbar artery may supply the tumor. Although selective chemoembolization via the tumor-feeding vessel of the lumbar artery can be achieved in most cases, overall tumor response is commonly unfavorable.« less

Effect of the human chorionic gonadotropin diet on patient outcomes.

PubMed

Goodbar, Nancy H; Foushee, Jaime A; Eagerton, David H; Haynes, Katie B; Johnson, Amanda A

2013-05-01

To report a case of left lower extremity deep vein thrombosis (DVT) and bilateral pulmonary embolisms in a patient who initiated the human chorionic gonadotropin (HCG) diet 2 weeks prior to presentation. A 64-year-old white female presented with leg swelling and shortness of breath. Lower extremity ultrasound revealed left leg DVT, and a computed tomography angiogram revealed bilateral pulmonary embolisms. A complete history and physical examination were unremarkable for any risk factors for acute thrombosis, with the exception of the initiation of the HCG diet approximately 2 weeks prior to presentation; the patient was taking 20 sublingual drops of HCG twice daily. Results of her hypercoagulable workup were negative. Upon admission, therapy was started with enoxaparin 120 mg subcutaneously twice daily and warfarin 5 mg orally once daily. According to the Naranjo probability scale, initiation of the HCG diet was a probable cause of our patient's adverse effects. The HCG diet has very few efficacy studies and no significant safety studies associated with its use. Six relevant studies were identified for assessment of efficacy, and only 1 was associated with a significant weight reduction in the HCG diet study population. All of these studies evaluated the use of the HCG diet via injections of the hormone and significant calorie restriction, which is known as the Simeons method. Currently marketed HCG products include sublingual drops, lozenges, and pellets, but none of these methods has an evidence-based efficacy and safety standard. As popularity of the HCG diet continues to increase, so do the potential adverse events associated with the management of weight loss via an unproven strategy. Patient safety information regarding this dieting strategy should be recognized by medical professionals.

Unilateral Acute Closed-Angle Glaucoma After Elective Lumbar Surgery Reveals Multiple Intracranial Aneurysms. A Case Report and Discussion on Workup of Differential Diagnoses.

PubMed

Storey, Christopher; Menger, Richard; Hefner, Matthew; Keating, Patrick; Ahmed, Osama; Guthikonda, Bharat

2015-11-01

The purpose of our paper is to present a case of a rare complication of posterior lumbar surgery. Our patient presented for elective lumbar decompression, which was complicated by durotomy. She then developed sudden headache and right eye pain once upright on postoperative day 2. Then on postoperative day 3, she developed a dilated nonreactive pupil with extraocular movements intact. A computed tomography scan of the head was negative for subarachnoid hemorrhage. Magnetic resonance angiography showed a possible right posterior communicating artery aneurysm. She was transferred to a tertiary center with a severe headache and a nonreactive pupil, raising concern for evolving third nerve palsy due to aneurysm. A cerebral angiogram was performed and showed multiple aneurysms. Aneurysm location did not explain the patient's symptoms, and ophthalmology was consulted. Elevated intraocular pressure was noted, and the patient was diagnosed with acute angle-closure glaucoma (AACG). Our patient was medically treated and subsequently underwent laser peripheral iridotomy. She has had improved vision and pupillary function at 1 month follow-up. The diagnosis is complicated by a durotomy, which led to cascade in the differential diagnosis to rule out intracranial pathology. Her age and home medications, which had sympathomimetic effects, placed her at increased risk, but lying prone in the dark under the drapes was likely the lead causative factor. In conclusion, a postoperative posterior spine patient with eye pain and changes in vision and pupils should be evaluated with AACG in mind due to the devastating consequences if left untreated or treatment is delayed. Copyright © 2015 Elsevier Inc. All rights reserved.

Vascular anatomy in children with univentricular hearts regarding transcatheter bidirectional Glenn anastomosis.

PubMed

Sizarov, Aleksander; Raimondi, Francesca; Bonnet, Damien; Boudjemline, Younes

2017-04-01

Transcatheter stent-secured Glenn anastomosis, aiming to reduce the invasiveness of palliation in patients with univentricular heart defects, has been reported in large experimental animals. The advent of biodegradable stents and tissue-engineered vascular grafts will make this procedure a reality in human patients. However, the relationship between the superior vena cava (SVC) and the right pulmonary artery (RPA) is different in humans. To characterise vascular anatomy in children with univentricular hearts, regarding technical aspects and device design for this procedure. Retrospective analysis of 35 thoracic computed tomography angiograms at a mean age of 18.1±22.4 months. Two types of arrangement between the SVC and the RPA were identified: anatomy convenient for immediate wire passage and stent deployment between the two vessels (60%); and pattern of early RPA branching, requiring the perforation wire to traverse the intervascular space to avoid entrance into the upper RPA branch (40%). In patients with the convenient vascular arrangement, the vessels were nearly perpendicular, having immediate contact, with the posterior SVC aspect partially "wrapping" the adjacent RPA in most patients. In patients with early RPA branching, the mean shortest SVC-to-central RPA distance was 4.3±2.7mm. For the total population, the mean length of proximal SVC that allowed stent deployment without covering the brachiocephalic vein was 15.6±5.1mm. A trumpet-shaped covered stent in a craniocaudal orientation reaching from the SVC into the prebranching RPA seems most suitable for achieving bidirectional Glenn anastomosis percutaneously in humans. However, the short length of the proximal SVC and the presence of early RPA branching pose challenges for optimal design of the dedicated device. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Establishment of a canine model of acute pulmonary embolism with definite right ventricular dysfunction through introduced autologous blood clots.

PubMed

Zhao, Lin-Bo; Jia, Zhen-Yu; Lu, Guang-Dong; Zhu, Yin-Su; Jing, Lei; Shi, Hai-Bin

2015-04-01

To establish a canine model of acute pulmonary embolism (PE) with right ventricular (RV) dysfunction using autologous blood clots and evaluate by echocardiography and contrast-enhanced Computed Tomography (CT). Autologous blood clots formed in vitro were introduced sequentially into the pulmonary arteries of eight healthy mixed-breed dogs while monitoring pulmonary and systemic hemodynamic function. Blood clots were injected until the mean pulmonary artery pressure (MPAP) reached two-three times the baseline pressure, which was maintained up to 1 hour. The RV function was assessed by echocardiography and ECG-gated dual-source contrast CT. All animals survived the imaging procedure. The post-injection pulmonary angiograms showed extensive PE, and MPAP increased from 16.50±2.45 mmHg to 43.13±4.91 mmHg (P<0.001). On echocardiography, the RV fractional area change decreased from 42.06±3.36 to 27.96±3.54 (P<0.001), and the RV myocardial performance increased from 0.20±0.05 to 0.63±0.16 (P<0.001). On CT, the RV end-systolic volume increased from 11.11±1.81 ml to 24.71±4.60 ml (P<0.001), RV end-diastolic volume from 20.73±2.83 ml to 34.63±5.76 ml (P<0.001), and the four-chamber RV/left ventricular diameter ratio from 0.38±0.07 to 0.81±0.14 (P<0.001). Acute PE with RV dysfunction was established in a large animal model through controlled injection of autologous blood clots, which may be useful for developing and evaluating new therapeutic approaches for acute PE with RV dysfunction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Myxedema coma and cardiac ischemia in relation to thyroid hormone replacement therapy in a 38-year-old Japanese woman.

PubMed

Taguchi, Takafumi; Iwasaki, Yasumasa; Asaba, Koichi; Takao, Toshihiro; Hashimoto, Kozo

2007-12-01

Although thyroid hormone deficiency, either clinical or subclinical, is an established risk factor for cardiovascular disease, coronary ischemia in a premenopausal woman in her 30s is relatively rare. A 38-year-old woman was referred to our hospital with severe breathlessness and depressed consciousness. Physical examination found facial, abdominal, and pretibial edema; coarse hair, hoarse voice, and dry skin; engorged jugular veins; a distant heart sound; and reduced bilateral entry of air into the chest. Laboratory examinations revealed severe hypothyroidism, hyperlipidemia, and elevated serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 125 (CA125). A computed tomography scan showed massive pleural and pericardial effusions. After 3 months of levothyroxine replacement therapy (initial dose: 12.5 microg/d; maintenance dose: 125 microg/d), all abnormal laboratory values associated with hypothyroidism returned to within normal ranges, with the exception of a transient and paradoxical rise in serum thyroid-stimulating hormone levels. However, 3 weeks after the initiation of therapy, the patient reported intermittent chest pains during the course of therapy, and a coronary artery angiogram revealed diffuse stenosis of all 3 branches. The patient underwent coronary artery bypass grafting, with subsequent improvement in coronary perfusion. Careful cardiovascular evaluation is recommended before the start of thyroid hormone replacement therapy. In addition, care should be taken in the interpretation of serum biomarkers of malignancy (eg, CEA, CA125) in patients with myxedema, as values may be elevated in a hypothyroid state. Long-standing hypothyroidism may be associated with severe coronary atherosclerosis, even in a relatively young, premenopausal woman. The potential adverse cardiovascular effects of thyroid hormone must be considered during replacement therapy, even in relatively young patients.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sailer, Anna M., E-mail: anni.sailer@mumc.nl; Haan, Michiel W. de, E-mail: m.de.haan@mumc.nl; Graaf, Rick de, E-mail: r.de.graaf@mumc.nl

PurposeThis study was designed to evaluate the feasibility of endovascular guidance by means of live fluoroscopy fusion with magnetic resonance angiography (MRA) and computed tomography angiography (CTA).MethodsFusion guidance was evaluated in 20 endovascular peripheral artery interventions in 17 patients. Fifteen patients had received preinterventional diagnostic MRA and two patients had undergone CTA. Time for fluoroscopy with MRA/CTA coregistration was recorded. Feasibility of fusion guidance was evaluated according to the following criteria: for every procedure the executing interventional radiologists recorded whether 3D road-mapping provided added value (yes vs. no) and whether PTA and/or stenting could be performed relying on the fusionmore » road-map without need for diagnostic contrast-enhanced angiogram series (CEAS) (yes vs. no). Precision of the fusion road-map was evaluated by recording maximum differences between the position of the vasculature on the virtual CTA/MRA images and conventional angiography.ResultsAverage time needed for image coregistration was 5 ± 2 min. Three-dimensional road-map added value was experienced in 15 procedures in 12 patients. In half of the patients (8/17), intervention was performed relying on the fusion road-map only, without diagnostic CEAS. In two patients, MRA roadmap showed a false-positive lesion. Excluding three patients with inordinate movements, mean difference in position of vasculature on angiography and MRA/CTA road-map was 1.86 ± 0.95 mm, implying that approximately 95 % of differences were between 0 and 3.72 mm (2 ± 1.96 standard deviation).ConclusionsFluoroscopy with MRA/CTA fusion guidance for peripheral artery interventions is feasible. By reducing the number of CEAS, this technology may contribute to enhance procedural safety.« less

Non-Acute Coronary Syndrome Anginal Chest Pain

PubMed Central

Agarwal, Megha; Mehta, Puja K.; Merz, C. Noel Bairey

2010-01-01

Anginal chest pain is one of the most common complaints in the outpatient setting. While much of the focus has been on identifying obstructive atherosclerotic coronary artery disease (CAD) as the cause of anginal chest pain, it is clear that microvascular coronary dysfunction (MCD) can also cause anginal chest pain as a manifestation of ischemic heart disease (IHD), and carries an increased cardiovascular risk. Epicardial coronary vasospasm, aortic stenosis, left ventricular hypertrophy, congenital coronary anomalies, mitral valve prolapse and abnormal cardiac nociception can also present as angina of cardiac origin. For non-acute coronary syndrome (ACS) stable chest pain, exercise treadmill testing (ETT) remains the primary tool for diagnosis of ischemia and cardiac risk stratification; however, in certain subsets of patients, such as women, ETT has a lower sensitivity and specificity for identifying obstructive CAD. When combined with an imaging modality, such as nuclear perfusion or echocardiography testing, the sensitivity and specificity of stress testing for detection of obstructive CAD improves significantly. Advancements in stress cardiac magnetic resonance imaging (MRI) enables detection of perfusion abnormalities in a specific coronary artery territory, as well as subendocardial ischemia associated with MCD. Coronary computed tomography angiography (CCTA) enables visual assessment of obstructive CAD, albeit with a higher radiation dose. Invasive coronary angiography (CA) remains the gold standard for diagnosis and treatment of obstructive lesions that cause medically refractory stable angina. Furthermore, in patients with normal coronary angiograms, the addition of coronary reactivity testing (CRT) can help diagnose endothelial dependent and independent microvascular dysfunction. Life-style modification and pharmacologic intervention remains the cornerstone of therapy to reduce morbidity and mortality in patients with stable angina. This review focuses on the pathophysiology, diagnosis, and treatment of stable, non-ACS anginal chest pain. PMID:20380951

Angiographic Evaluation of Feeding Arteries of Hepatocellular Carcinoma in the Caudate Lobe of the Liver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyayama, Shiro, E-mail: s-miyayama@fukui.saiseikai.or.jp; Yamashiro, Masashi; Hattori, Yuki

2011-12-15

Purpose: To evaluate the origins of feeders of hepatocellular carcinoma (HCC) in the caudate lobe (S1). Materials and Methods: Eighty-eight HCCs (mean diameter 21.4 mm) were treated by chemoembolization. The tumor-feeding caudate artery was confirmed when a tumor stain was demonstrated on angiogram and iodized oil was accumulated into the HCC and S1 on computed tomography (CT). The origins were divided into R{sub 1} (right proximal), R{sub 2} (right distal), L{sub 1} (left proximal), L{sub 2} (left distal), A (anterior segmental), P (posterior segmental), M (middle hepatic or medial segmental), Ph (proper hepatic), Ch (common hepatic), and Ex (extrahepatic). Themore » origins of feeders supplying HCCs in the Spiegel lobe (SP; n = 36), the paracaval portion (PC; n = 38), and the caudate process (CP; n = 14) were also analyzed. Results: One hundred sixteen feeders were identified: 11 (9.5%) arose from R{sub 1}; 21 (18.1%) arose from R{sub 2}; nine arose (0.9%) from L{sub 1}; 15 (12.9%) arose from L{sub 2}; 24 (20.7%) arose from A; 25 (21.6%) arose from P; seven (6.0%) arose from M; one (0.9%) arose from Ph; and three (2.6%) arose from Ex. HCCs in the SP and the PC were fed by feeders from both hepatic arteries (the ratios of right to left were 3:2 and 3:1, respectively), and HCCs in the CP were dominantly fed by feeders from the right hepatic artery. Conclusion: The caudate artery most frequently arises from the right hepatic artery, followed with almost equal frequency by the left hepatic, the anterior segmental, and the posterior segmental artery. The origins of the caudate arteries differ according to the subsegmental locations.« less

Unenhanced and Contrast-Enhanced Ultrasonography During Hepatic Transarterial Embolization and Chemoembolization With Drug-Eluting Beads

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moschouris, Hippocrates, E-mail: hipmosch@gmail.co; Malagari, Katerina; Kornezos, Ioannis

2010-12-15

The purpose of this study was to describe and evaluate the findings of unenhanced ultrasonography (US) and contrast-enhanced ultrasonography (CEUS) when these modalities are applied during transarterial embolization (TAE) or transarterial chemoembolization (TACE) of liver tumors. Sixteen tumors (9 hepatocellular carcinomas, 5 metastases from colorectal cancer, and 2 hemangiomas) were treated with TAE with microspheres and/or TACE with drug-eluting beads. All of these lesions were studied with intraprocedural unenhanced US and 12 were studied with intraprocedural CEUS. For the latter, a second-generation echo-enhancer (SonoVue; Bracco, Milan, Italy) and a low mechanical index technique were used. Intraprocedural findings were classified accordingmore » to an arbitrary scale and were compared with pretreatment imaging (CEUS and computed tomography or CEUS and magnetic resonance imaging), with postembolization angiography, and with follow-up results. On unenhanced intraprocedural US, 13 of 16 tumors demonstrated intralesional high-level echoes of varying extent. These feature correlated poorly (r = 0.33, p = 0.097) with and generally underestimated the actual extent of necrosis. Exceptionally, high-level echoes that occupied the largest part of the treated lesions were associated with >50% tumor necrosis. Intraprocedural CEUS clearly depicted immediate partial or complete disappearance of tumor enhancement as a result of TAE/TACE. Three of 6 tumors with complete devascularization on postembolization angiogram showed residual enhancement on intraprocedural CEUS. Intraprocedural CEUS findings correlated closely (r = 0.91, p = 0.002) with follow-up findings. Intraprocedural sonography, particularly with echo-enhancers, could be used for intraprocedural monitoring in selected cases of liver tumors that undergo TAE or TACE.« less

Pitfalls and Rewards for Implementing Ocular Motor Testing in Acute Vestibular Syndrome: A Pilot Project.

PubMed

Dumitrascu, Oana M; Torbati, Sam; Tighiouart, Mourad; Newman-Toker, David E; Song, Shlee S

2017-03-01

Isolated acute vestibular syndrome (iAVS) presentations to the emergency department (ED) pose management challenges, given the concerns for posterior circulation strokes. False-negative brain imaging may erroneously reassure clinicians, whereas HINTS-plus examination outperforms imaging to screen for strokes in iAVS. We studied the feasibility of implementing HINTS-plus testing in the ED, aiming to reduce neuroimaging in patients with iAVS. We launched an institutional Quality Improvement initiative, using DMAIC methodology. The outcome measures [proportion of iAVS subjects who had HINTS-plus examinations and underwent neuroimaging by computed tomography/magnetic resonance imaging (CT/MRI)] were compared before and after the established intervention. The intervention consisted of formal training for neurologists and emergency physicians on how to perform, document, and interpret HINTS-plus and implementation of novel iAVS management algorithm. Neuroimaging was not recommended if HINTS-plus suggested peripheral vestibular etiology. If a central process was suspected, brain MRI/MR angiogram was performed. Head CT was reserved only for thrombolytic time-window cases. In the first 2 months postimplementation, HINTS-plus testing performance by neurologists increased from 0% to 80% (P=0.007), and by ED providers from 0% to 9.09% (P=0.367). Head CT scans were reduced from 18.5% to 6.25%. Brain MRI use was reduced from 51.8% to 31.2%. About 60% of the iAVS subjects were discharged from the ED; none were readmitted or had another ED presentation in the ensuing 30 days. Implementation of HINTS-plus evaluation in the ED is valuable and feasible for neurologists, but challenging for emergency physicians. Future studies should determine the "dose-response" curve of educational interventions.

Implications of renal artery anatomy for endovascular repair using fenestrated, branched, or parallel stent graft techniques.

PubMed

Mendes, Bernardo C; Oderich, Gustavo S; Reis de Souza, Leonardo; Banga, Peter; Macedo, Thanila A; DeMartino, Randall R; Misra, Sanjay; Gloviczki, Peter

2016-05-01

This study evaluated renal artery (RA) and accessory renal artery (ARA) anatomy and implications for endovascular repair using fenestrated, branched, or parallel (chimney, snorkel, and periscope) stent graft techniques. We analyzed the digital computed tomography angiograms of 520 consecutive patients treated by open or fenestrated endovascular repair for complex abdominal aortic aneurysms (2000-2012). RA/ARA anatomy was assessed using diameter, length, angles, and kidney perfusion based on analysis of estimated volumetric kidney parenchyma. Endovascular suitability was determined by RA diameter ≥4 mm, length to RA bifurcation ≥13 mm, and preservation of >75% of a single kidney or >60% of two kidneys by volumetric kidney parenchyma analysis. There were 222 juxtarenal (43%), 241 suprarenal (46%), and 57 type IV thoracoabdominal aortic aneurysms (11%), Analysis of 1009 RAs and 177 ARAs showed endovascular incorporation was possible in 884 RAs (88%) and 30 ARAs (17%) using the proposed criteria. One or more factors rendered RA incorporation unsuitable in 97 patients (19%), including early bifurcation in 45 (9%), small diameter in 28 (5%), or inability to preserve kidney parenchyma in 28 (5%). Other anatomic issues were present in 170 patients (33%) that would increase technical difficulty to RA incorporation using transfemoral access, including excessive downward angulation in 125 (24%), high-grade stenosis in 51 (10%), or prior renal stents in 11 (2%). Independent of the endovascular technique that is selected to treat a complex abdominal aortic aneurysm, one of five patients has anatomic limitations to endovascular incorporation. In these patients, open repair may provide the best alterative to maximize RA patency and preserve renal function. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Classification of gutter type in parallel stenting during endovascular aortic aneurysm repair.

PubMed

Overeem, Simon P; Boersen, Johannes T; Schuurmann, Richte C L; Groot Jebbink, Erik; Slump, Cornelis H; Reijnen, Michel M P J; de Vries, Jean-Paul P M

2017-08-01

Gutters can be described as the loss of continuous apposition between the main body of the endograft, the chimney stent graft, and the aortic wall. Gutters have been associated with increased risk of type IA endoleaks and are considered to be the Achilles' heel of chimney endovascular aneurysm repair (ch-EVAR). However, there is no classification yet to classify and quantify gutter types after ch-EVAR. Different gutter types can be distinguished by their morphologic appearance in two- and three-dimensional views and reconstructed slices perpendicular to the center lumen line. Three main categories are defined by (1) the most proximal beginning of the gutter, (2) the length of gutter alongside the endograft, and (3) its distal end. Type A gutters originate at the proximal fabric of an endograft, type B gutters originate as loss of apposition of the chimney stent graft in the branch vessel, and type C gutters start below the fabric of the endograft. To determine eventual changes of gutter size during follow-up computed tomography angiograms (CTAs), measurements may be performed with dedicated software on the follow-up CTA scan to assess the extent of gutters over the aortic circumference, ranging from 0° to 360° of freedom, together with the maximum gap between the endograft material and the aortic wall as it appears on reconstructed axial CTA scan slices. The proposed gutter classification enables a uniform nomenclature in the current ch-EVAR literature and a more accurate risk assessment of gutter-associated endoleaks. Moreover, it allows monitoring of eventual progression of gutter size during follow-up. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Cone beam computed tomography: basics and applications in dentistry.

PubMed

Venkatesh, Elluru; Elluru, Snehal Venkatesh

2017-01-01

The introduction of cone beam computed tomography (CBCT) devices, changed the way oral and maxillofacial radiology is practiced. CBCT was embraced into the dental settings very rapidly due to its compact size, low cost, low ionizing radiation exposure when compared to medical computed tomography. Alike medical CT, 3 dimensional evaluation of the maxillofacial region with minimal distortion is offered by the CBCT. This article provides an overview of basics of CBCT technology and reviews the specific application of CBCT technology to oral and maxillofacial region with few illustrations.

Microstructure of cotton fibrous assemblies based on computed tomography

NASA Astrophysics Data System (ADS)

Jing, Hui; Yu, Weidong

2017-12-01

This paper describes for the first time the analysis of inner microstructure of cotton fibrous assemblies using computed tomography. Microstructure parameters such as packing density, fractal dimension as well as porosity including open porosity, closed porosity and total porosity are calculated based on 2D data from computed tomography. Values of packing density and fractal dimension are stable in random oriented fibrous assemblies, and there exists a satisfactory approximate linear relationship between them. Moreover, poles analysis indicates that porosity represents the tightness of fibrous assemblies and open poles are main existence.

Progress of projection computed tomography by upgrading of the beamline 37XU of SPring-8

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terada, Yasuko, E-mail: yterada@spring8.or.jp; Suzuki, Yoshio; Uesugi, Kentaro

2016-01-28

Beamline 37XU at SPring-8 has been upgraded for nano-focusing applications. The length of the beamline has been extended to 80 m. By utilizing this length, the beamline has advantages for experiments such as X-ray focusing, X-ray microscopic imaging and X-ray computed tomography. Projection computed tomography measurements were carried out at experimental hutch 3 located 80 m from the light source. CT images of a microcapsule have been successfully obtained with a wide X-ray energy range.

The use of iohexol as oral contrast for computed tomography of the abdomen and pelvis.

PubMed

Horton, Karen M; Fishman, Elliot K; Gayler, Bob

2008-01-01

Positive oral contrast agents (high-osmolar iodinated solutions [high-osmolar contrast medium] or barium sulfate suspensions) are used routinely for abdominal computed tomography. However, these agents are not ideal. Patients complain about the taste and, sometimes, refuse to drink the required quantity. Nausea, vomiting, and diarrhea are frequent. In certain clinical indications, either barium suspensions or high-osmolar contrast mediums may be contraindicated. This technical note describes the potential advantages of using low-osmolar iodinated solutions as an oral contrast agent for computed tomography.

Phase-contrast x-ray computed tomography for observing biological specimens and organic materials

NASA Astrophysics Data System (ADS)

Momose, Atsushi; Takeda, Tohoru; Itai, Yuji

1995-02-01

A novel three-dimensional x-ray imaging method has been developed by combining a phase-contrast x-ray imaging technique with x-ray computed tomography. This phase-contrast x-ray computed tomography (PCX-CT) provides sectional images of organic specimens that would produce absorption-contrast x-ray CT images with little contrast. Comparing PCX-CT images of rat cerebellum and cancerous rabbit liver specimens with corresponding absorption-contrast CT images shows that PCX-CT is much more sensitive to the internal structure of organic specimens.

Stored-fluorography mode reduces radiation dose during cardiac catheterization measured with OSLD dosimeter

NASA Astrophysics Data System (ADS)

Ting, Chien-Yi; Chen, Zhih-Cherng; Tang, Kuo-Ting; Liu, Wei-Chung; Lin, Chun-Chih; Wang, Hsin-Ell

2015-12-01

Coronary angiogram is an imperative tool for diagnosis of coronary artery diseases, in which cine-angiography is a commonly used method. Although the angiography proceeds under radiation, the potential risk of radiation exposure for both the patients and the operators was seldom noticed. In this study, the absorbed radiation dose in stored-fluorography mode was compared with that in cine-angiography mode by using optically simulated luminescent dosimeters to realize their effects on radiation dose. Patients received coronary angiogram via radial artery approach were randomized into the stored-fluorography group (N=30) or the cine-angiography group (N=30). The excluded criteria were: 1. women at pregnancy or on breast feeding, 2. chronic kidney diseases with glomerular filtration rate less than 60 mL/min. During the coronary angiogram, absorbed dose of the patients and the operator radiation exposure was measured with optically simulated luminescent dosimeter (OSLD). The absorbed dose of the patients in the stored-fluorography group (3.13±0.25 mGy) was apparently lower than that in the cine-angiography group (65.57±5.37 mGy; P<0.001). For the operator, a statistical difference (P<0.001) was also found between the stored-fluorography group (0.09163 μGy) and the cine-angiography (0.6519μGy). Compared with traditional cine-angiography mode, the stored-fluorography mode can apparently reduce radiation exposure of the patients and the operator in coronary angiogram.

Customized CT angiogram planning for intraoperative transesophageal echography-guided endovascular exclusion of thoracic aorta penetrating ulcer.

PubMed

Piazza, Michele; Lupia, Mario; Grego, Franco; Antonello, Michele

2015-04-01

The technique is demonstrated in a 78-year-old man; the preoperative CT angiogram showed a descending thoracic aorta ulcer of 5.9 cm in maximum diameter and 3.8 cm longitudinal extension. A ZTEG-2P-36-127-PF (Cook Medical) single tubular endograft was planned to be deployed. From the preoperative CT angiogram we planned to land 4.7 cm above the midline of the descending thoracic aorta ulcer and 8.0 cm below. In the operating room, under radioscopic vision the centre of the transesophageal echography probe was used as marker to identify the correspondent midline of the descending thoracic aorta ulcer and a centimeter-sized pigtail catheter in the aorta was used to calculate the desired length above and below the ulcer midline. The endograft was introduced and placed in the desired position compared to the transesophageal echography probe and the catheter; under transesophageal echography vision the graft was finally deployed. The CT angiogram at 1 month showed the correct endograft position, descending thoracic aorta ulcer exclusion with no signs of endoleak. In selected cases, this method allows planning in advance safe stent graft positioning and deployment totally assisted by transesophageal echography, with no risk of periprocedural contrast-related renal failure and reduced radiation exposure for the patient and operators. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Three-Station Three-dimensional Bolus-Chase MR Angiography with Real-time Fluoroscopic Tracking

PubMed Central

Johnson, Casey P.; Weavers, Paul T.; Borisch, Eric A.; Grimm, Roger C.; Hulshizer, Thomas C.; LaPlante, Christine C.; Rossman, Phillip J.; Glockner, James F.; Young, Phillip M.

2014-01-01

Purpose To determine the feasibility of using real-time fluoroscopic tracking for bolus-chase magnetic resonance (MR) angiography of peripheral vasculature to image three stations from the aortoiliac bifurcation to the pedal arteries. Materials and Methods This prospective study was institutional review board approved and HIPAA compliant. Eight healthy volunteers (three men; mean age, 48 years; age range, 30–81 years) and 13 patients suspected of having peripheral arterial disease (five men; mean age, 67 years; age range, 47–81 years) were enrolled and provided informed consent. All subjects were imaged with the fluoroscopic tracking MR angiographic protocol. Ten patients also underwent a clinical computed tomographic (CT) angiographic runoff examination. Two readers scored the MR angiographic studies for vessel signal intensity and sharpness and presence of confounding artifacts and venous contamination at 35 arterial segments. Mean aggregate scores were assessed. The paired MR angiographic and CT angiographic studies also were scored for visualization of disease, reader confidence, and overall diagnostic quality and were compared by using a Wilcoxon signed rank test. Results Real-time fluoroscopic tracking performed well technically in all studies. Vessel segments were scored good to excellent in all but the following categories: For vessel signal intensity and sharpness, the abdominal aorta, iliac arteries, distal plantar arteries, and plantar arch were scored as fair to good; and for presence of confounding artifacts, the abdominal aorta and iliac arteries were scored as fair. The MR angiograms and CT angiograms did not differ significantly in any scoring category (reader 1: P = .50, .39, and .39; reader 2: P = .41, .61, and .33, respectively). CT scores were substantially better in 20% (four of 20) and 25% (five of 20) of the pooled evaluations for the visualization of disease and overall image quality categories, respectively, versus 5% (one of 20) for MR scores in both categories. Conclusion Three-station bolus-chase MR angiography with real-time fluoroscopic tracking provided high-spatial-resolution arteriograms of the peripheral vasculature, enabled precise triggering of table motion, and compared well with CT angiograms. © RSNA, 2014 Online supplemental material is available for this article. PMID:24635676

Contours identification of elements in a cone beam computed tomography for investigating maxillary cysts

NASA Astrophysics Data System (ADS)

Chioran, Doina; Nicoarǎ, Adrian; Roşu, Şerban; Cǎrligeriu, Virgil; Ianeş, Emilia

2013-10-01

Digital processing of two-dimensional cone beam computer tomography slicesstarts by identification of the contour of elements within. This paper deals with the collective work of specialists in medicine and applied mathematics in computer science on elaborating and implementation of algorithms in dental 2D imagery.

Neuroanatomy of cranial computed tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kretschmann, H.J.; Weinrich, W.

1985-01-01

Based on the fundamental structures visualized by means of computed tomography, the authors present the functional systems which are relevant in neurology by means of axial cross-sections. All drawings were prepared from original preparations by means of a new technique which is similar to the grey values of X-ray CT and nuclear magnetic resonance tomography. A detailed description is given of the topics of neurofunctional lesions.

Frozen Gaussian approximation for 3D seismic tomography

NASA Astrophysics Data System (ADS)

Chai, Lihui; Tong, Ping; Yang, Xu

2018-05-01

Three-dimensional (3D) wave-equation-based seismic tomography is computationally challenging in large scales and high-frequency regime. In this paper, we apply the frozen Gaussian approximation (FGA) method to compute 3D sensitivity kernels and seismic tomography of high-frequency. Rather than standard ray theory used in seismic inversion (e.g. Kirchhoff migration and Gaussian beam migration), FGA is used to compute the 3D high-frequency sensitivity kernels for travel-time or full waveform inversions. Specifically, we reformulate the equations of the forward and adjoint wavefields for the purpose of convenience to apply FGA, and with this reformulation, one can efficiently compute the Green’s functions whose convolutions with source time function produce wavefields needed for the construction of 3D kernels. Moreover, a fast summation method is proposed based on local fast Fourier transform which greatly improves the speed of reconstruction as the last step of FGA algorithm. We apply FGA to both the travel-time adjoint tomography and full waveform inversion (FWI) on synthetic crosswell seismic data with dominant frequencies as high as those of real crosswell data, and confirm again that FWI requires a more sophisticated initial velocity model for the convergence than travel-time adjoint tomography. We also numerically test the accuracy of applying FGA to local earthquake tomography. This study paves the way to directly apply wave-equation-based seismic tomography methods into real data around their dominant frequencies.

Pediatric minor head trauma: do cranial CT scans change the therapeutic approach?

PubMed

Andrade, Felipe P; Montoro, Roberto; Oliveira, Renan; Loures, Gabriela; Flessak, Luana; Gross, Roberta; Donnabella, Camille; Puchnick, Andrea; Suzuki, Lisa; Regacini, Rodrigo

2016-10-01

1) To verify clinical signs correlated with appropriate cranial computed tomography scan indications and changes in the therapeutic approach in pediatric minor head trauma scenarios. 2) To estimate the radiation exposure of computed tomography scans with low dose protocols in the context of trauma and the additional associated risk. Investigators reviewed the medical records of all children with minor head trauma, which was defined as a Glasgow coma scale ≥13 at the time of admission to the emergency room, who underwent computed tomography scans during the years of 2013 and 2014. A change in the therapeutic approach was defined as a neurosurgical intervention performed within 30 days, hospitalization, >12 hours of observation, or neuro-specialist evaluation. Of the 1006 children evaluated, 101 showed some abnormality on head computed tomography scans, including 49 who were hospitalized, 16 who remained under observation and 36 who were dismissed. No patient underwent neurosurgery. No statistically significant relationship was observed between patient age, time between trauma and admission, or signs/symptoms related to trauma and abnormal imaging results. A statistically significant relationship between abnormal image results and a fall higher than 1.0 meter was observed (p=0.044). The mean effective dose was 2.0 mSv (0.1 to 6.8 mSv), corresponding to an estimated additional cancer risk of 0.05%. A computed tomography scan after minor head injury in pediatric patients did not show clinically relevant abnormalities that could lead to neurosurgical indications. Patients who fell more than 1.0 m were more likely to have changes in imaging tests, although these changes did not require neurosurgical intervention; therefore, the use of computed tomography scans may be questioned in this group. The results support the trend of more careful indications for cranial computed tomography scans for children with minor head trauma.

Computed Tomography Perfusion, Magnetic Resonance Imaging, and Histopathological Findings After Laparoscopic Renal Cryoablation: An In Vivo Pig Model.

PubMed

Nielsen, Tommy Kjærgaard; Østraat, Øyvind; Graumann, Ole; Pedersen, Bodil Ginnerup; Andersen, Gratien; Høyer, Søren; Borre, Michael

2017-08-01

The present study investigates how computed tomography perfusion scans and magnetic resonance imaging correlates with the histopathological alterations in renal tissue after cryoablation. A total of 15 pigs were subjected to laparoscopic-assisted cryoablation on both kidneys. After intervention, each animal was randomized to a postoperative follow-up period of 1, 2, or 4 weeks, after which computed tomography perfusion and magnetic resonance imaging scans were performed. Immediately after imaging, open bilateral nephrectomy was performed allowing for histopathological examination of the cryolesions. On computed tomography perfusion and magnetic resonance imaging examinations, rim enhancement was observed in the transition zone of the cryolesion 1week after laparoscopic-assisted cryoablation. This rim enhancement was found to subside after 2 and 4 weeks of follow-up, which was consistent with the microscopic examinations revealing of fibrotic scar tissue formation in the peripheral zone of the cryolesion. On T2 magnetic resonance imaging sequences, a thin hypointense rim surrounded the cryolesion, separating it from the adjacent renal parenchyma. Microscopic examinations revealed hemorrhage and later hemosiderin located in the peripheral zone. No nodular or diffuse contrast enhancement was found in the central zone of the cryolesions at any follow-up stage on neither computed tomography perfusion nor magnetic resonance imaging. On microscopic examinations, the central zone was found to consist of coagulative necrosis 1 week after laparoscopic-assisted cryoablation, which was partially replaced by fibrotic scar tissue 4 weeks following laparoscopic-assisted cryoablation. Both computed tomography perfusion and magnetic resonance imaging found the renal collecting system to be involved at all 3 stages of follow-up, but on microscopic examination, the urothelium was found to be intact in all cases. In conclusion, cryoablation effectively destroyed renal parenchyma, leaving the urothelium intact. Both computed tomography perfusion and magnetic resonance imaging reflect the microscopic findings but with some differences, especially regarding the peripheral zone. Magnetic resonance imaging seems an attractive modality for early postoperative follow-up.

Validation of a computational knee joint model using an alignment method for the knee laxity test and computed tomography.

PubMed

Kang, Kyoung-Tak; Kim, Sung-Hwan; Son, Juhyun; Lee, Young Han; Koh, Yong-Gon

2017-01-01

Computational models have been identified as efficient techniques in the clinical decision-making process. However, computational model was validated using published data in most previous studies, and the kinematic validation of such models still remains a challenge. Recently, studies using medical imaging have provided a more accurate visualization of knee joint kinematics. The purpose of the present study was to perform kinematic validation for the subject-specific computational knee joint model by comparison with subject's medical imaging under identical laxity condition. The laxity test was applied to the anterior-posterior drawer under 90° flexion and the varus-valgus under 20° flexion with a series of stress radiographs, a Telos device, and computed tomography. The loading condition in the computational subject-specific knee joint model was identical to the laxity test condition in the medical image. Our computational model showed knee laxity kinematic trends that were consistent with the computed tomography images, except for negligible differences because of the indirect application of the subject's in vivo material properties. Medical imaging based on computed tomography with the laxity test allowed us to measure not only the precise translation but also the rotation of the knee joint. This methodology will be beneficial in the validation of laxity tests for subject- or patient-specific computational models.

Computed tomography or rhinoscopy as the first-line procedure for suspected nasal tumor: a pilot study.

PubMed

Finck, Marlène; Ponce, Frédérique; Guilbaud, Laurent; Chervier, Cindy; Floch, Franck; Cadoré, Jean-Luc; Chuzel, Thomas; Hugonnard, Marine

2015-02-01

There are no evidence-based guidelines as to whether computed tomography (CT) or endoscopy should be selected as the first-line procedure when a nasal tumor is suspected in a dog or a cat and only one examination can be performed. Computed tomography and rhinoscopic features of 17 dogs and 5 cats with a histopathologically or cytologically confirmed nasal tumor were retrospectively reviewed. The level of suspicion for nasal neoplasia after CT and/or rhinoscopy was compared to the definitive diagnosis. Twelve animals underwent CT, 14 underwent rhinoscopy, and 4 both examinations. Of the 12 CT examinations performed, 11 (92%) resulted in the conclusion that a nasal tumor was the most likely diagnosis compared with 9/14 (64%) for rhinoscopies. Computed tomography appeared to be more reliable than rhinoscopy for detecting nasal tumors and should therefore be considered as the first-line procedure.

Computed tomography or rhinoscopy as the first-line procedure for suspected nasal tumor: A pilot study

PubMed Central

Finck, Marlène; Ponce, Frédérique; Guilbaud, Laurent; Chervier, Cindy; Floch, Franck; Cadoré, Jean-Luc; Chuzel, Thomas; Hugonnard, Marine

2015-01-01

There are no evidence-based guidelines as to whether computed tomography (CT) or endoscopy should be selected as the first-line procedure when a nasal tumor is suspected in a dog or a cat and only one examination can be performed. Computed tomography and rhinoscopic features of 17 dogs and 5 cats with a histopathologically or cytologically confirmed nasal tumor were retrospectively reviewed. The level of suspicion for nasal neoplasia after CT and/or rhinoscopy was compared to the definitive diagnosis. Twelve animals underwent CT, 14 underwent rhinoscopy, and 4 both examinations. Of the 12 CT examinations performed, 11 (92%) resulted in the conclusion that a nasal tumor was the most likely diagnosis compared with 9/14 (64%) for rhinoscopies. Computed tomography appeared to be more reliable than rhinoscopy for detecting nasal tumors and should therefore be considered as the first-line procedure. PMID:25694669

Review of cardiovascular imaging in The Journal of Nuclear Cardiology in 2014: Part 1 of 2: Positron emission tomography, computed tomography, and neuronal imaging.

PubMed

AlJaroudi, Wael A; Hage, Fadi G

2015-06-01

The year 2014 has been an exciting year for the cardiovascular imaging community with significant advances in the realm of nuclear and multimodality cardiac imaging. In this new feature of the Journal of Nuclear Cardiology, we will summarize some of the breakthroughs that were published in the Journal in 2014 in 2 sister articles. This first article will concentrate on publications dealing with cardiac positron emission tomography (PET), computed tomography (CT), and neuronal imaging.

Trends in micro- and nanoComputed Tomography 2008-2010

NASA Astrophysics Data System (ADS)

Stock, S. R.

2010-09-01

Trends in micro- and nanoComputed Tomography (CT) from January 2008 through July 2010 are the subject of this brief report which takes up where a previous report in Developments in X-ray Tomography VI (2008) concluded. First, the number of systems operating world-wide is estimated. The main focus is on what searches of three citation indices (Web of Science, Compendex and PubMed) reveal about the field of micro- and nanoCT. Given research-fielddependent and disparate terminology used by investigators, searches were on "microtomography", "microCT" and "synchrotron tomography".

Incidental renal stones in potential live kidney donors: prevalence, assessment and donation, including role of ex vivo ureteroscopy.

PubMed

Olsburgh, Jonathon; Thomas, Kay; Wong, Kathie; Bultitude, Matthew; Glass, Jonathan; Rottenberg, Giles; Silas, Lisa; Hilton, Rachel; Koffman, Geoff

2013-05-01

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Previously, donors with asymptomatic stones found incidentally on CT were not considered ideal donor candidates because of the presumed risk of morbidity to both the donor and recipient. Increasingly, studies show that these risks are low. This study aims to evaluate the long-term safety of using ex vivo ureteroscopy to remove the stones from the donor kidney on the bench before donation. Outcomes so far suggest that this technique can safely render a kidney stone-free before transplantation. This has led to 20 more transplants in our institution than would otherwise be possible. To evaluate the prevalence of asymptomatic renal stones in our potential donor population. To assess the safety and success of ex vivo ureteroscopy (ExURS) to remove stones from explanted donor kidneys before transplantation. We conducted a retrospective analysis of 377 computed tomography (CT) angiograms of potential kidney donors between October 2004 and May 2007 to assess the prevalence of asymptomatic renal stones in our donor population. Between October 2005 and October 2011, kidneys from suitable donors underwent ExURS. Stones were removed using basket extraction or were fragmented with holmium laser on bench before transplantation. Immediate and long-term complications of the transplanted recipients were recorded. Donors were followed with yearly ultrasonography of the remaining kidney in addition to standard follow-up protocol. Review of 377 CT angiograms between October 2004 to May 2007 showed a 5% prevalence of asymptomatic renal stones. Out of 55 potential donors (19 identified between October 2004 to May 2007 and a further 36 identified since May 2007), 20 donors with stones proceeded to donation, with stone size ranging from 2 to 12 mm. Of the patients, 17 proceeded to ExURS. Stones were removed in 10 patients; five with basket retrieval, four with laser fragmentation and one with both laser fragmentation and basket retrieval. There were no early or late allograft stone-related complications and no evidence of stones on follow-up imaging at a mean (range) of 10 (1-24) months. There has been no reported stone recurrence in any of the donors to date and no stone on ultrasonography of eight donors with >1-year follow-up (mean 26 months, range 12-49 months). Asymptomatic renal stones are present in 5% of our donors. ExURS can be safely used to remove stones in these kidneys before transplantation, without the risk of subjecting the donor to an additional stone-removing procedure. Continued long-term follow-up of donors and recipients is still required to ensure the safety of this approach. © 2012 The Authors. BJU International © 2012 BJU International.

[Measurement of intracranial hematoma volume by personal computer].

PubMed

DU, Wanping; Tan, Lihua; Zhai, Ning; Zhou, Shunke; Wang, Rui; Xue, Gongshi; Xiao, An

2011-01-01

To explore the method for intracranial hematoma volume measurement by the personal computer. Forty cases of various intracranial hematomas were measured by the computer tomography with quantitative software and personal computer with Photoshop CS3 software, respectively. the data from the 2 methods were analyzed and compared. There was no difference between the data from the computer tomography and the personal computer (P>0.05). The personal computer with Photoshop CS3 software can measure the volume of various intracranial hematomas precisely, rapidly and simply. It should be recommended in the clinical medicolegal identification.

Computed Tomography of the Musculoskeletal System.

PubMed

Ballegeer, Elizabeth A

2016-05-01

Computed tomography (CT) has specific uses in veterinary species' appendicular musculoskeletal system. Parameters for acquisition of images, interpretation limitations, as well as published information regarding its use in small animals is reviewed. Copyright © 2016 Elsevier Inc. All rights reserved.

Cholangiocarcinoma associated with limbic encephalitis and early cerebral abnormalities detected by 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography-positron emission tomography: a case report.

PubMed

Schmidt, Sergio L; Schmidt, Juliana J; Tolentino, Julio C; Ferreira, Carlos G; de Almeida, Sergio A; Alvarenga, Regina P; Simoes, Eunice N; Schmidt, Guilherme J; Canedo, Nathalie H S; Chimelli, Leila

2016-07-20

Limbic encephalitis was originally described as a rare clinical neuropathological entity involving seizures and neuropsychological disturbances. In this report, we describe cerebral patterns visualized by positron emission tomography in a patient with limbic encephalitis and cholangiocarcinoma. To our knowledge, there is no other description in the literature of cerebral positron emission tomography findings in the setting of limbic encephalitis and subsequent diagnosis of cholangiocarcinoma. We describe a case of a 77-year-old Caucasian man who exhibited persistent cognitive changes 2 years before his death. A cerebral scan obtained at that time by 2-deoxy-2-[fluorine-18]fluoro- D -glucose integrated with computed tomography-positron emission tomography showed low radiotracer uptake in the frontal and temporal lobes. Cerebrospinal fluid analysis indicated the presence of voltage-gated potassium channel antibodies. Three months before the patient's death, a lymph node biopsy indicated a cholangiocarcinoma, and a new cerebral scan obtained by 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography-positron emission tomography showed an increment in the severity of metabolic deficit in the frontal and parietal lobes, as well as hypometabolism involving the temporal lobes. Two months before the patient's death, cerebral metastases were detected on a contrast-enhanced computed tomographic scan. Postmortem examination revealed a cholangiocarcinoma with multiple metastases including the lungs and lymph nodes. The patient's brain weighed 1300 g, and mild cortical atrophy, ex vacuo dilation of the ventricles, and mild focal thickening of the cerebellar leptomeninges, which were infiltrated by neoplastic epithelial cells, were observed. These findings support the need for continued vigilance in malignancy surveillance in patients with limbic encephalitis and early cerebral positron emission tomographic scan abnormalities. The difficulty in early diagnosis of small tumors, such as a cholangiocarcinoma, is discussed in the context of the clinical utility of early cerebral hypometabolism detected by 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography-positron emission tomography in patients with rapidly progressive dementia.

Intraoperative 3-Dimensional Computed Tomography and Navigation in Foot and Ankle Surgery.

PubMed

Chowdhary, Ashwin; Drittenbass, Lisca; Dubois-Ferrière, Victor; Stern, Richard; Assal, Mathieu

2016-09-01

Computer-assisted orthopedic surgery has developed dramatically during the past 2 decades. This article describes the use of intraoperative 3-dimensional computed tomography and navigation in foot and ankle surgery. Traditional imaging based on serial radiography or C-arm-based fluoroscopy does not provide simultaneous real-time 3-dimensional imaging, and thus leads to suboptimal visualization and guidance. Three-dimensional computed tomography allows for accurate intraoperative visualization of the position of bones and/or navigation implants. Such imaging and navigation helps to further reduce intraoperative complications, leads to improved surgical outcomes, and may become the gold standard in foot and ankle surgery. [Orthopedics.2016; 39(5):e1005-e1010.]. Copyright 2016, SLACK Incorporated.

Domain identification in impedance computed tomography by spline collocation method

NASA Technical Reports Server (NTRS)

Kojima, Fumio

1990-01-01

A method for estimating an unknown domain in elliptic boundary value problems is considered. The problem is formulated as an inverse problem of integral equations of the second kind. A computational method is developed using a splice collocation scheme. The results can be applied to the inverse problem of impedance computed tomography (ICT) for image reconstruction.

Fast automatic segmentation of anatomical structures in x-ray computed tomography images to improve fluorescence molecular tomography reconstruction.

PubMed

Freyer, Marcus; Ale, Angelique; Schulz, Ralf B; Zientkowska, Marta; Ntziachristos, Vasilis; Englmeier, Karl-Hans

2010-01-01

The recent development of hybrid imaging scanners that integrate fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) allows the utilization of x-ray information as image priors for improving optical tomography reconstruction. To fully capitalize on this capacity, we consider a framework for the automatic and fast detection of different anatomic structures in murine XCT images. To accurately differentiate between different structures such as bone, lung, and heart, a combination of image processing steps including thresholding, seed growing, and signal detection are found to offer optimal segmentation performance. The algorithm and its utilization in an inverse FMT scheme that uses priors is demonstrated on mouse images.

Clinical applications of cone beam computed tomography in endodontics: A comprehensive review.

PubMed

Cohenca, Nestor; Shemesh, Hagay

2015-09-01

The use of cone beam computed tomography (CBCT) in endodontics has been extensively reported in the literature. Compared with the traditional spiral computed tomography, limited field of view (FOV) CBCT results in a fraction of the effective absorbed dose of radiation. The purpose of this manuscript is to review the application and advantages associated with advanced endodontic problems and complications, while reducing radiation exposure during complex endodontic procedures. The benefits of the added diagnostic information provided by intraoperative CBCT images in select cases justify the risk associated with the limited level of radiation exposure.

Dry coupling for whole-body small-animal photoacoustic computed tomography

NASA Astrophysics Data System (ADS)

Yeh, Chenghung; Li, Lei; Zhu, Liren; Xia, Jun; Li, Chiye; Chen, Wanyi; Garcia-Uribe, Alejandro; Maslov, Konstantin I.; Wang, Lihong V.

2017-04-01

We have enhanced photoacoustic computed tomography with dry acoustic coupling that eliminates water immersion anxiety and wrinkling of the animal and facilitates incorporating complementary modalities and procedures. The dry acoustic coupler is made of a tubular elastic membrane enclosed by a closed transparent water tank. The tubular membrane ensures water-free contact with the animal, and the closed water tank allows pressurization for animal stabilization. The dry coupler was tested using a whole-body small-animal ring-shaped photoacoustic computed tomography system. Dry coupling was found to provide image quality comparable to that of conventional water coupling.

Linear-array based full-view high-resolution photoacoustic computed tomography of whole mouse brain functions in vivo

NASA Astrophysics Data System (ADS)

Li, Lei; Zhang, Pengfei; Wang, Lihong V.

2018-02-01

Photoacoustic computed tomography (PACT) is a non-invasive imaging technique offering high contrast, high resolution, and deep penetration in biological tissues. We report a photoacoustic computed tomography (PACT) system equipped with a high frequency linear array for anatomical and functional imaging of the mouse whole brain. The linear array was rotationally scanned in the coronal plane to achieve the full-view coverage. We investigated spontaneous neural activities in the deep brain by monitoring the hemodynamics and observed strong interhemispherical correlations between contralateral regions, both in the cortical layer and in the deep regions.

Broadband Terahertz Computed Tomography Using a 5k-pixel Real-time THz Camera

NASA Astrophysics Data System (ADS)

Trichopoulos, Georgios C.; Sertel, Kubilay

2015-07-01

We present a novel THz computed tomography system that enables fast 3-dimensional imaging and spectroscopy in the 0.6-1.2 THz band. The system is based on a new real-time broadband THz camera that enables rapid acquisition of multiple cross-sectional images required in computed tomography. Tomographic reconstruction is achieved using digital images from the densely-packed large-format (80×64) focal plane array sensor located behind a hyper-hemispherical silicon lens. Each pixel of the sensor array consists of an 85 μm × 92 μm lithographically fabricated wideband dual-slot antenna, monolithically integrated with an ultra-fast diode tuned to operate in the 0.6-1.2 THz regime. Concurrently, optimum impedance matching was implemented for maximum pixel sensitivity, enabling 5 frames-per-second image acquisition speed. As such, the THz computed tomography system generates diffraction-limited resolution cross-section images as well as the three-dimensional models of various opaque and partially transparent objects. As an example, an over-the-counter vitamin supplement pill is imaged and its material composition is reconstructed. The new THz camera enables, for the first time, a practical application of THz computed tomography for non-destructive evaluation and biomedical imaging.

[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. Copyright © 2011 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

Inter- and intraobserver reliability of the vertebral, local and segmental kyphosis in 120 traumatic lumbar and thoracic burst fractures: evaluation in lateral X-rays and sagittal computed tomographies

PubMed Central

Brunner, Alexander; Gühring, Markus; Schmälzle, Traude; Weise, Kuno; Badke, Andreas

2009-01-01

Evaluation of the kyphosis angle in thoracic and lumbar burst fractures is often used to indicate surgical procedures. The kyphosis angle could be measured as vertebral, segmental and local kyphosis according to the method of Cobb. The vertebral, segmental and local kyphosis according to the method of Cobb were measured at 120 lateral X-rays and sagittal computed tomographies of 60 thoracic and 60 lumbar burst fractures by 3 independent observers on 2 separate occasions. Osteoporotic fractures were excluded. The intra- and interobserver reliability of these angles in X-ray and computed tomogram, using the intra class correlation coefficient (ICC) were evaluated. Highest reproducibility showed the segmental kyphosis followed by the vertebral kyphosis. For thoracic fractures segmental kyphosis shows in X-ray “excellent” inter- and intraobserver reliabilities (ICC 0.826, 0.802) and for lumbar fractures “good” to “excellent” inter- and intraobserver reliabilities (ICC = 0.790, 0.803). In computed tomography, the segmental kyphosis showed “excellent” inter- and intraobserver reliabilities (ICC = 0.824, 0.801) for thoracic and “excellent” inter- and intraobserver reliabilities (ICC = 0.874, 0.835) for the lumbar fractures. Regarding both diagnostic work ups (X-ray and computed tomography), significant differences were evaluated in interobserver reliabilities for vertebral kyphosis measured in lumbar fracture X-rays (p = 0.035) and interobserver reliabilities for local kyphosis, measured in thoracic fracture X-rays (p = 0.010). Regarding both fracture localizations (thoracic and lumbar fractures), significant differences could only be evaluated in interobserver reliabilities for the local kyphosis measured in computed tomographies (p = 0.045) and in intraobserver reliabilities for the vertebral kyphosis measured in X-rays (p = 0.024). “Good” to “excellent” inter- and intraobserver reliabilities for vertebral, segmental and local kyphosis in X-ray make these angles to a helpful tool, indicating surgical procedures. For the practical use in lateral X-ray, we emphasize the determination of the segmental kyphosis, because of the highest reproducibility of this angle. “Good” to “excellent” inter- and intraobserver reliabilities for these three angles could also be evaluated in computed tomographies. Therefore, also in computed tomography, the use of these three angles seems to be generally possible. For a direct correlation of the results in lateral X-ray and in computed tomography, further studies should be needed. PMID:19953277

Dipyridamole stress myocardial perfusion by computed tomography in patients with left bundle branch block.

PubMed

Cabeda, Estêvan Vieira; Falcão, Andréa Maria Gomes; Soares, José; Rochitte, Carlos Eduardo; Nomura, César Higa; Ávila, Luiz Francisco Rodrigues; Parga, José Rodrigues

2015-12-01

Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB). To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP) by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA) (stenosis ≥ 70%) as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA) and compare the results with those of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy. Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography. Independent examiners performed per-patient and per-coronary territory assessments. All patients gave written informed consent to participate in the study that was approved by the institution's ethics committee. The patients' mean age was 62 ± 10 years. The mean dose of radiation for the tomography protocol was 9.3 ± 4.6 mSv. With regard to CTP, the per-patient values for sensitivity, specificity, positive and negative predictive values, and accuracy were 86%, 81%, 80%, 87%, and 83%, respectively (p = 0.001). The per-territory values were 63%, 86%, 65%, 84%, and 79%, respectively (p < 0.001). In both analyses, the addition of CTP to CTA achieved higher diagnostic accuracy for detecting myocardial ischemia than SPECT (p < 0.001). The use of the stress tomography protocol is feasible and has good diagnostic accuracy for assessing myocardial ischemia in patients with LBBB.

Association of heat shock protein70-2 (HSP70-2) gene polymorphism with coronary artery disease in an Iranian population.

PubMed

Mardan-Nik, Maryam; Pasdar, Alireza; Jamialahmadi, Khadijeh; Biabangard-Zak, Atefeh; Mirhafez, Seyed Reza; Ghalandari, Marzieh; Tajfard, Mohammad; Mohebati, Mohsen; Esmaily, Habibollah; Ferns, Gordon A; Ghayour-Mobarhan, Majid

2014-10-25

Coronary artery disease (CAD) is an inflammatory process and a major cause of mortality and morbidity. The (heat shock protein70-2) HSP70-2 gene is reported to be associated with coronary artery disease possibly by affecting the regulation of pro-inflammatory cytokines such as TNF-α. The association between CAD and the HSP70-2 gene +1267A>G polymorphism has been studied in some populations but there are no data about this association in the Iranian population. We have investigated the association between the HSP70-2 gene +1267A>G polymorphism and angiographically defined CAD within an Iranian population. We determined the presence of the HSP70-2 gene +1267A>G polymorphism in 628 patients with CAD and 307 healthy individuals using PCR-RFLP. Of the patients, 433 (68%) had >50% stenosis (CAD+) and the remaining 195 patients had <50% stenosis (CAD-), based on coronary angiography. Angiogram positive patients were subdivided into three groups: those with single (n=113), double (n=134), and triple vessels (n=186) disease. A significant higher frequency of AG+GG genotypes (G allele carriers) was observed in angiogram positive and angiogram negative groups compared to controls in a dominant analysis model of the HSP70-2 gene +1267A>G position (51.2 vs. 43.2, P=0.002, OR=1.37) (51.0 vs. 43.2, P=0.01, OR=1.37). The allele frequency of the HSP70-2 G was also significantly higher in angiogram positive and angiogram negative groups compared to the control group (51.2 vs. 43.2, P=0.002, OR=1.37) (51.0 vs. 43.2, P=0.01, OR=1.37). These results suggest that HSP70-2 +1267 polymorphism may influence the risk of CAD in Iranian population, however further studies are needed to clarify the role of other HSP70-2 gene polymorphisms in the pathogenesis of the CAD. Copyright © 2014 Elsevier B.V. All rights reserved.

Role of positron emission tomography/computed tomography in breast cancer.

PubMed

Bourgeois, Austin C; Warren, Lance A; Chang, Ted T; Embry, Scott; Hudson, Kathleen; Bradley, Yong C

2013-09-01

Although positron emission tomography (PET) imaging may not be used in the diagnosis of breast cancer, the use of PET/computed tomography is imperative in all aspects of breast cancer staging, treatment, and follow-up. PET will continue to be relevant in personalized medicine because accurate tumor status will be even more critical during and after the transition from a generic metabolic agent to receptor imaging. Positron emission mammography is an imaging proposition that may have benefits in lower doses, but its use is limited without new radiopharmaceuticals. Copyright © 2013 Elsevier Inc. All rights reserved.

Transurethral Ultrasound Diffraction Tomography

DTIC Science & Technology

2007-03-01

the covariance matrix was derived. The covariance reduced to that of the X- ray CT under the assumptions of linear operator and real data.[5] The...the covariance matrix in the linear x- ray computed tomography is a special case of the inverse scattering matrix derived in this paper. The matrix was...is derived in Sec. IV, and its relation to that of the linear x- ray computed tomography appears in Sec. V. In Sec. VI, the inverse scattering

APPLICATION OF COMPUTER AIDED TOMOGRAPHY (CAT) TO THE STUDY OF MARINE BENTIC COMMUNITIES

EPA Science Inventory

Sediment cores were imaged using a Computer-Aided Tomography (CT) scanner at Massachusetts General Hospital, Boston, Massachusetts, United States. Procedures were developed, using the attenuation of X-rays, to differentiate between sediment and the water contained in macrobenthic...

How to interpret computed tomography of the lumbar spine

PubMed Central

Mobasheri, R; Das, T; Vaidya, S; Mallik, S; El-Hussainy, M; Casey, A

2014-01-01

Computed tomography (CT) of the spine has remained an important tool in the investigation of spinal pathology. This article helps to explain the basics of CT of the lumbar spine to allow the clinician better use of this diagnostic tool. PMID:25245727

Clinical and computed tomography features of secondary renal hyperparathyroidism

PubMed Central

Vanbrugghe, Benoît; Blond, Laurent; Carioto, Lisa; Carmel, Eric Norman; Nadeau, Marie-Eve

2011-01-01

An atypical case of secondary renal hyperparathyroidism was diagnosed in a 9-year-old miniature schnauzer after a skull computed tomography (CT) showed the presence of 2 bilateral and symmetrical soft tissue maxillary masses, and osteopenia of the skull. PMID:21532826

[Embolization of the feeding artery of a meningioma with dangerous vascular anastomosis between the middle meningeal artery and the ophthalmic artery].

PubMed

Meguro, Toshinari; Tomita, Yusuke; Tanabe, Tomoyuki; Muraoka, Kenichiro; Terada, Kinya; Hirotsune, Nobuyuki; Nishino, Shigeki

2013-11-01

Preoperative embolization of intracranial meningioma has been applied to reduce intraoperative blood loss and to facilitate microsurgical removal of a tumor. It is well known that one of the reasons of the neurological risk of embolization is due to dangerous anastomosis between the extracranial and the intracranial arteries. One of the most known and dangerous case of anastomosis is between the middle meningeal artery to the ophthalmic artery. A 48-year-old woman underwent preoperative embolization of a large right middle cranial fossa meningioma. The right external carotid angiogram showed that the tumor was fed by the right middle meningeal artery and there was no branch to the right orbital region. The right internal carotid angiogram showed that the right ophthalmic artery originated from the right internal carotid artery and there was no branch to the tumor. The selective angiogram of the anterior branch of the middle meningeal artery disclosed the anastomosis to the right ophthalmic artery. Following embolization of the anterior branch of the middle meningeal artery, the patient underwent embolization of the main feeding branch of the meningioma. She successfully underwent surgical removal of the tumor without any blood transfusion and was discharged without neurological deficit. In addition, to avoid complication in embolization of the feeding artery of a skull base meningioma, clinicians must be aware of the dangerous anastomosis between the middle meningeal artery and the ophthalmic artery, even if conventional external and internal carotid angiograms do not show any anastomosis.

Young man presenting with out-of-hospital cardiac arrest.

PubMed

Huang, Hans David; Lombardi, William L; Steinberg, Zachary Louis

2018-06-22

A man in his early 30s with remote history of a febrile rash as a toddler presented to the emergency room following an out-of-hospital cardiac arrest while riding his bicycle. He received bystander cardiopulmonary resuscitation and one shock from an automatic external defibrillator, successfully restoring sinus rhythm. On arrival, he was haemodynamically stable without ECG evidence of ST segment changes to suggest active ischaemia, and an initial troponin I was mildly elevated at 0.10 ng/mL (normal <0.04 ng/mL). A CT angiogram (CTA) was obtained showing a normal-appearing aorta and no abnormal extracardiac findings. Urgent coronary angiography was performed; images are shown in figure 1A-C. Echocardiogram revealed a mildly reduced left ventricular ejection fraction (45%) with a hypokinetic inferior wall.heartjnl;heartjnl-2018-312966v1/F1F1F1Figure 1(A) Right coronary artery angiogram in the left anterior oblique cranial projection. (B) Left coronary artery angiogram in the right anterior oblique caudal projection. (C) Left coronary artery angiogram in the right anterior oblique cranial projection. CAUD, caudal; CRAN, cranial; LAO, left anterior oblique; RAO, right anterior oblique. What is the next best step in the management of this patient at this time?Complete revascularisation via percutaneous coronary intervention (PCI).Referral for coronary artery bypass surgery (CABG).Initiation of high-dose steroids.Initiation of dual-antiplatelet therapy without planned revascularisation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Magnetic resonance fingerprinting based on realistic vasculature in mice

PubMed Central

Pouliot, Philippe; Gagnon, Louis; Lam, Tina; Avti, Pramod K.; Bowen, Chris; Desjardins, Michèle; Kakkar, Ashok K.; Thorin, E.; Sakadzic, Sava; Boas, David A.; Lesage, Frédéric

2017-01-01

Magnetic resonance fingerprinting (MRF) was recently proposed as a novel strategy for MR data acquisition and analysis. A variant of MRF called vascular MRF (vMRF) followed, that extracted maps of three parameters of physiological importance: cerebral oxygen saturation (SatO2), mean vessel radius and cerebral blood volume (CBV). However, this estimation was based on idealized 2-dimensional simulations of vascular networks using random cylinders and the empirical Bloch equations convolved with a diffusion kernel. Here we focus on studying the vascular MR fingerprint using real mouse angiograms and physiological values as the substrate for the MR simulations. The MR signal is calculated ab initio with a Monte Carlo approximation, by tracking the accumulated phase from a large number of protons diffusing within the angiogram. We first study the identifiability of parameters in simulations, showing that parameters are fully estimable at realistically high signal-to-noise ratios (SNR) when the same angiogram is used for dictionary generation and parameter estimation, but that large biases in the estimates persist when the angiograms are different. Despite these biases, simulations show that differences in parameters remain estimable. We then applied this methodology to data acquired using the GESFIDE sequence with SPIONs injected into 9 young wild type and 9 old atherosclerotic mice. Both the pre injection signal and the ratio of post-to-pre injection signals were modeled, using 5-dimensional dictionaries. The vMRF methodology extracted significant differences in SatO2, mean vessel radius and CBV between the two groups, consistent across brain regions and dictionaries. Further validation work is essential before vMRF can gain wider application. PMID:28043909

Peri-implant assessment via cone beam computed tomography and digital periapical radiography: an ex vivo study.

PubMed

Silveira-Neto, Nicolau; Flores, Mateus Ericson; De Carli, João Paulo; Costa, Max Dória; Matos, Felipe de Souza; Paranhos, Luiz Renato; Linden, Maria Salete Sandini

2017-11-01

This research evaluated detail registration in peri-implant bone using two different cone beam computer tomography systems and a digital periapical radiograph. Three different image acquisition protocols were established for each cone beam computer tomography apparatus, and three clinical situations were simulated in an ex vivo fresh pig mandible: buccal bone defect, peri-implant bone defect, and bone contact. Data were subjected to two analyses: quantitative and qualitative. The quantitative analyses involved a comparison of real specimen measures using a digital caliper in three regions of the preserved buccal bone - A, B and E (control group) - to cone beam computer tomography images obtained with different protocols (kp1, kp2, kp3, ip1, ip2, and ip3). In the qualitative analyses, the ability to register peri-implant details via tomography and digital periapical radiography was verified, as indicated by twelve evaluators. Data were analyzed with ANOVA and Tukey's test (α=0.05). The quantitative assessment showed means statistically equal to those of the control group under the following conditions: buccal bone defect B and E with kp1 and ip1, peri-implant bone defect E with kp2 and kp3, and bone contact A with kp1, kp2, kp3, and ip2. Qualitatively, only bone contacts were significantly different among the assessments, and the p3 results differed from the p1 and p2 results. The other results were statistically equivalent. The registration of peri-implant details was influenced by the image acquisition protocol, although metal artifacts were produced in all situations. The evaluators preferred the Kodak 9000 3D cone beam computer tomography in most cases. The evaluators identified buccal bone defects better with cone beam computer tomography and identified peri-implant bone defects better with digital periapical radiography.

Single-Photon Emission Computed Tomography/Computed Tomography Imaging in a Rabbit Model of Emphysema Reveals Ongoing Apoptosis In Vivo

PubMed Central

Goldklang, Monica P.; Tekabe, Yared; Zelonina, Tina; Trischler, Jordis; Xiao, Rui; Stearns, Kyle; Romanov, Alexander; Muzio, Valeria; Shiomi, Takayuki; Johnson, Lynne L.

2016-01-01

Evaluation of lung disease is limited by the inability to visualize ongoing pathological processes. Molecular imaging that targets cellular processes related to disease pathogenesis has the potential to assess disease activity over time to allow intervention before lung destruction. Because apoptosis is a critical component of lung damage in emphysema, a functional imaging approach was taken to determine if targeting apoptosis in a smoke exposure model would allow the quantification of early lung damage in vivo. Rabbits were exposed to cigarette smoke for 4 or 16 weeks and underwent single-photon emission computed tomography/computed tomography scanning using technetium-99m–rhAnnexin V-128. Imaging results were correlated with ex vivo tissue analysis to validate the presence of lung destruction and apoptosis. Lung computed tomography scans of long-term smoke–exposed rabbits exhibit anatomical similarities to human emphysema, with increased lung volumes compared with controls. Morphometry on lung tissue confirmed increased mean linear intercept and destructive index at 16 weeks of smoke exposure and compliance measurements documented physiological changes of emphysema. Tissue and lavage analysis displayed the hallmarks of smoke exposure, including increased tissue cellularity and protease activity. Technetium-99m–rhAnnexin V-128 single-photon emission computed tomography signal was increased after smoke exposure at 4 and 16 weeks, with confirmation of increased apoptosis through terminal deoxynucleotidyl transferase dUTP nick end labeling staining and increased tissue neutral sphingomyelinase activity in the tissue. These studies not only describe a novel emphysema model for use with future therapeutic applications, but, most importantly, also characterize a promising imaging modality that identifies ongoing destructive cellular processes within the lung. PMID:27483341

Quantitative X-ray fluorescence computed tomography for low-Z samples using an iterative absorption correction algorithm

NASA Astrophysics Data System (ADS)

Huang, Rong; Limburg, Karin; Rohtla, Mehis

2017-05-01

X-ray fluorescence computed tomography is often used to measure trace element distributions within low-Z samples, using algorithms capable of X-ray absorption correction when sample self-absorption is not negligible. Its reconstruction is more complicated compared to transmission tomography, and therefore not widely used. We describe in this paper a very practical iterative method that uses widely available transmission tomography reconstruction software for fluorescence tomography. With this method, sample self-absorption can be corrected not only for the absorption within the measured layer but also for the absorption by material beyond that layer. By combining tomography with analysis for scanning X-ray fluorescence microscopy, absolute concentrations of trace elements can be obtained. By using widely shared software, we not only minimized the coding, took advantage of computing efficiency of fast Fourier transform in transmission tomography software, but also thereby accessed well-developed data processing tools coming with well-known and reliable software packages. The convergence of the iterations was also carefully studied for fluorescence of different attenuation lengths. As an example, fish eye lenses could provide valuable information about fish life-history and endured environmental conditions. Given the lens's spherical shape and sometimes the short distance from sample to detector for detecting low concentration trace elements, its tomography data are affected by absorption related to material beyond the measured layer but can be reconstructed well with our method. Fish eye lens tomography results are compared with sliced lens 2D fluorescence mapping with good agreement, and with tomography providing better spatial resolution.

Qualitative assessment of contrast-enhanced magnetic resonance angiography using breath-hold and non-breath-hold techniques in the portal venous system

NASA Astrophysics Data System (ADS)

Goo, Eun-Hoe; Kim, Sun-Ju; Dong, Kyung-Rae; Kim, Kwang-Choul; Chung, Woon-Kwan

2016-09-01

The purpose of this study is to evaluate the image quality in delineation of the portal venous systems with two different methods, breath-hold and non-breath-hold by using the 3D FLASH sequence. We used a 1.5 T system to obtain magnetic resonance(MR)images. Arterial and portal phase 3D FLASH images were obtained with breath-hold after a bolus injection of GD-DOTA. The detection of PVS on the MR angiograms was classified into three grades. First, the angiograms of the breath-hold method showed well the portal vein, the splenic vein and the superior mesenteric vein systems in 13 of 15 patients (86%) and the inferior mesenteric vein system in 6 of 15 patients (40%), Second, MR angiograms of the non-breath-hold method demonstrated the PVS and the SMV in 12 of 15 patients (80%) and the IMV in 5 of 15 patients (33%). Our study showed contrast-enhanced 3D FLASH MR angiography, together with the breath-hold technique, may provide reliable and accurate information on the portal venous system.

Correlation of computed tomography, magnetic resonance imaging and clinical outcome in acute carbon monoxide poisoning.

PubMed

Ozcan, Namik; Ozcam, Giray; Kosar, Pinar; Ozcan, Ayse; Basar, Hulya; Kaymak, Cetin

2016-01-01

Carbon monoxide is a toxic gas for humans and is still a silent killer in both developed and developing countries. The aim of this case series was to evaluate early radiological images as a predictor of subsequent neuropsychological sequelae, following carbon monoxide poisoning. After carbon monoxide exposure, early computed tomography scans and magnetic resonance imaging findings of a 52-year-old woman showed bilateral lesions in the globus pallidus. This patient was discharged and followed for 90 days. The patient recovered without any neurological sequela. In a 58-year-old woman exposed to carbon monoxide, computed tomography showed lesions in bilateral globus pallidus and periventricular white matter. Early magnetic resonance imaging revealed changes similar to that like in early tomography images. The patient recovered and was discharged from hospital. On the 27th day of exposure, the patient developed disorientation and memory impairment. Late magnetic resonance imaging showed diffuse hyperintensity in the cerebral white matter. White matter lesions which progress to demyelination and end up in neuropsychological sequelae cannot always be diagnosed by early computed tomography and magnetic resonance imaging in carbon monoxide poisoning. Copyright © 2014 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

Radiation-Induced Liver Injury Mimicking Metastatic Disease in a Patient With Esophageal Cancer: Correlation of Positron Emission Tomography/Computed Tomography With Magnetic Resonance Imaging and Literature Review.

PubMed

Rabe, Tiffany M; Yokoo, Takeshi; Meyer, Jeffrey; Kernstine, Kemp H; Wang, David; Khatri, Gaurav

2016-01-01

Post-radiation therapy evaluation of distal esophageal cancers with positron emission tomography/computed tomography can be problematic. Differentiation of recurrent neoplasm from postradiation changes is difficult in areas of fluorodeoxyglucose avidity in adjacent, incidentally irradiated organs. Few studies have described the magnetic resonance imaging appearance of radiation-induced hepatic injury. We report a case of focal radiation-induced liver injury with a new focus of fluorodeoxyglucose uptake on posttreatment positron emission tomography as well as masslike enhancement and signal abnormality on magnetic resonance imaging, thus mimicking new liver metastasis. Correlation with radiation planning images suggested the correct diagnosis, which was confirmed on follow-up imaging.

A multiresolution approach to iterative reconstruction algorithms in X-ray computed tomography.

PubMed

De Witte, Yoni; Vlassenbroeck, Jelle; Van Hoorebeke, Luc

2010-09-01

In computed tomography, the application of iterative reconstruction methods in practical situations is impeded by their high computational demands. Especially in high resolution X-ray computed tomography, where reconstruction volumes contain a high number of volume elements (several giga voxels), this computational burden prevents their actual breakthrough. Besides the large amount of calculations, iterative algorithms require the entire volume to be kept in memory during reconstruction, which quickly becomes cumbersome for large data sets. To overcome this obstacle, we present a novel multiresolution reconstruction, which greatly reduces the required amount of memory without significantly affecting the reconstructed image quality. It is shown that, combined with an efficient implementation on a graphical processing unit, the multiresolution approach enables the application of iterative algorithms in the reconstruction of large volumes at an acceptable speed using only limited resources.

X-ray Computed Tomography.

ERIC Educational Resources Information Center

Michael, Greg

2001-01-01

Describes computed tomography (CT), a medical imaging technique that produces images of transaxial planes through the human body. A CT image is reconstructed mathematically from a large number of one-dimensional projections of a plane. The technique is used in radiological examinations and radiotherapy treatment planning. (Author/MM)

The Power of Computer-aided Tomography to Investigate Marine Benthic Communities

EPA Science Inventory

Utilization of Computer-aided-Tomography (CT) technology is a powerful tool to investigate benthic communities in aquatic systems. In this presentation, we will attempt to summarize our 15 years of experience in developing specific CT methods and applications to marine benthic co...

Three-dimensional evaluation of human jaw bone microarchitecture: correlation between the microarchitectural parameters of cone beam computed tomography and micro-computer tomography.

PubMed

Kim, Jo-Eun; Yi, Won-Jin; Heo, Min-Suk; Lee, Sam-Sun; Choi, Soon-Chul; Huh, Kyung-Hoe

2015-12-01

To evaluate the potential feasibility of cone beam computed tomography (CBCT) in the assessment of trabecular bone microarchitecture. Sixty-eight specimens from four pairs of human jaw were scanned using both micro-computed tomography (micro-CT) of 19.37-μm voxel size and CBCT of 100-μm voxel size. The correlation of 3-dimensional parameters between CBCT and micro-CT was evaluated. All parameters, except bone-specific surface and trabecular thickness, showed linear correlations between the 2 imaging modalities (P < .05). Among the parameters, bone volume, percent bone volume, trabecular separation, and degree of anisotropy (DA) of CBCT images showed strong correlations with those of micro-CT images. DA showed the strongest correlation (r = 0.693). Most microarchitectural parameters from CBCT were correlated with those from micro-CT. Some microarchitectural parameters, especially DA, could be used as strong predictors of bone quality in the human jaw. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of a continuous-rotation, high-speed scanning protocol for micro-computed tomography.

PubMed

Kerl, Hans Ulrich; Isaza, Cristina T; Boll, Hanne; Schambach, Sebastian J; Nolte, Ingo S; Groden, Christoph; Brockmann, Marc A

2011-01-01

Micro-computed tomography is used frequently in preclinical in vivo research. Limiting factors are radiation dose and long scan times. The purpose of the study was to compare a standard step-and-shoot to a continuous-rotation, high-speed scanning protocol. Micro-computed tomography of a lead grid phantom and a rat femur was performed using a step-and-shoot and a continuous-rotation protocol. Detail discriminability and image quality were assessed by 3 radiologists. The signal-to-noise ratio and the modulation transfer function were calculated, and volumetric analyses of the femur were performed. The radiation dose of the scan protocols was measured using thermoluminescence dosimeters. The 40-second continuous-rotation protocol allowed a detail discriminability comparable to the step-and-shoot protocol at significantly lower radiation doses. No marked differences in volumetric or qualitative analyses were observed. Continuous-rotation micro-computed tomography significantly reduces scanning time and radiation dose without relevantly reducing image quality compared with a normal step-and-shoot protocol.

Management of Liver Cancer Argon-helium Knife Therapy with Functional Computer Tomography Perfusion Imaging.

PubMed

Wang, Hongbo; Shu, Shengjie; Li, Jinping; Jiang, Huijie

2016-02-01

The objective of this study was to observe the change in blood perfusion of liver cancer following argon-helium knife treatment with functional computer tomography perfusion imaging. Twenty-seven patients with primary liver cancer treated with argon-helium knife and were included in this study. Plain computer tomography (CT) and computer tomography perfusion (CTP) imaging were conducted in all patients before and after treatment. Perfusion parameters including blood flows, blood volume, hepatic artery perfusion fraction, hepatic artery perfusion, and hepatic portal venous perfusion were used for evaluating therapeutic effect. All parameters in liver cancer were significantly decreased after argon-helium knife treatment (p < 0.05 to all). Significant decrease in hepatic artery perfusion was also observed in pericancerous liver tissue, but other parameters kept constant. CT perfusion imaging is able to detect decrease in blood perfusion of liver cancer post-argon-helium knife therapy. Therefore, CTP imaging would play an important role for liver cancer management followed argon-helium knife therapy. © The Author(s) 2014.

Stress Computed Tomography Myocardial Perfusion Imaging: A New Topic in Cardiology.

PubMed

Seitun, Sara; Castiglione Morelli, Margherita; Budaj, Irilda; Boccalini, Sara; Galletto Pregliasco, Athena; Valbusa, Alberto; Cademartiri, Filippo; Ferro, Carlo

2016-02-01

Since its introduction about 15 years ago, coronary computed tomography angiography has become today the most accurate clinical instrument for noninvasive assessment of coronary atherosclerosis. Important technical developments have led to a continuous stream of new clinical applications together with a significant reduction in radiation dose exposure. Latest generation computed tomography scanners (≥ 64 slices) allow the possibility of performing static or dynamic perfusion imaging during stress by using coronary vasodilator agents (adenosine, dipyridamole, or regadenoson), combining both functional and anatomical information in the same examination. In this article, the emerging role and state-of-the-art of myocardial computed tomography perfusion imaging are reviewed and are illustrated by clinical cases from our experience with a second-generation dual-source 128-slice scanner (Somatom Definition Flash, Siemens; Erlangen, Germany). Technical aspects, data analysis, diagnostic accuracy, radiation dose and future prospects are reviewed. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Overcoming spatio-temporal limitations using dynamically scaled in vitro PC-MRI - A flow field comparison to true-scale computer simulations of idealized, stented and patient-specific left main bifurcations.

PubMed

Beier, Susann; Ormiston, John; Webster, Mark; Cater, John; Norris, Stuart; Medrano-Gracia, Pau; Young, Alistair; Gilbert, Kathleen; Cowan, Brett

2016-08-01

The majority of patients with angina or heart failure have coronary artery disease. Left main bifurcations are particularly susceptible to pathological narrowing. Flow is a major factor of atheroma development, but limitations in imaging technology such as spatio-temporal resolution, signal-to-noise ratio (SNRv), and imaging artefacts prevent in vivo investigations. Computational fluid dynamics (CFD) modelling is a common numerical approach to study flow, but it requires a cautious and rigorous application for meaningful results. Left main bifurcation angles of 40°, 80° and 110° were found to represent the spread of an atlas based 100 computed tomography angiograms. Three left mains with these bifurcation angles were reconstructed with 1) idealized, 2) stented, and 3) patient-specific geometry. These were then approximately 7× scaled-up and 3D printing as large phantoms. Their flow was reproduced using a blood-analogous, dynamically scaled steady flow circuit, enabling in vitro phase-contrast magnetic resonance (PC-MRI) measurements. After threshold segmentation the image data was registered to true-scale CFD of the same coronary geometry using a coherent point drift algorithm, yielding a small covariance error (σ 2 <;5.8×10 -4 ). Natural-neighbour interpolation of the CFD data onto the PC-MRI grid enabled direct flow field comparison, showing very good agreement in magnitude (error 2-12%) and directional changes (r 2 0.87-0.91), and stent induced flow alternations were measureable for the first time. PC-MRI over-estimated velocities close to the wall, possibly due to partial voluming. Bifurcation shape determined the development of slow flow regions, which created lower SNRv regions and increased discrepancies. These can likely be minimised in future by testing different similarity parameters to reduce acquisition error and improve correlation further. It was demonstrated that in vitro large phantom acquisition correlates to true-scale coronary flow simulations when dynamically scaled, and thus can overcome current PC-MRI's spatio-temporal limitations. This novel method enables experimental assessment of stent induced flow alternations, and in future may elevate CFD coronary flow simulations by providing sophisticated boundary conditions, and enable investigations of stenosis phantoms.

Fatal Road Traffic Vehicle Collisions With Pedestrian Victims: Forensic Postmortem Computed Tomography and Autopsy Correlation.

PubMed

Chatzaraki, Vasiliki; Thali, Michael J; Ampanozi, Garyfalia; Schweitzer, Wolf

2018-06-01

Fatal car-to-pedestrian collisions regularly appear in the forensic pathologist's routine, particularly in places of extended urbanization. Postmortem computed tomography has gained an exceptional role to supplement autopsy worldwide, giving information that is supplementary or complimentary to conventional autopsy. In this retrospective study, a total number of 320 findings in a series of 21 pedestrians fatally hit by cars and trucks of both postmortem computed tomography and autopsy were correlated. According to our results, it is best to combine both methods to give well-founded answers to questions pertaining to both collision reconstruction and cause of death.

[Axial computer tomography of the neurocranium (author's transl)].

PubMed

Stöppler, L

1977-05-27

Computer tomography (CT), a new radiographic examination technique, is very highly efficient, for it has high informative content with little stress for the patient. In contrast to the conventional X-ray technology, CT succeeds, by direct presentation of the structure of the soft parts, in obtaining information which comes close to that of macroscopic neuropathology. The capacity and limitations of the method at the present stage of development are reported. Computer tomography cannot displace conventional neuroradiological methods of investigation, although it is rightly presented as a screening method and helps towards selective use. Indications, technical integration and handling of CT are prerequisites for the exhaustive benefit of the excellent new technique.

Ambient noise adjoint tomography for a linear array in North China

NASA Astrophysics Data System (ADS)

Zhang, C.; Yao, H.; Liu, Q.; Yuan, Y. O.; Zhang, P.; Feng, J.; Fang, L.

2017-12-01

Ambient noise tomography based on dispersion data and ray theory has been widely utilized for imaging crustal structures. In order to improve the inversion accuracy, ambient noise tomography based on the 3D adjoint approach or full waveform inversion has been developed recently, however, the computational cost is tremendous. In this study we present 2D ambient noise adjoint tomography for a linear array in north China with significant computational efficiency compared to 3D ambient noise adjoint tomography. During the preprocessing, we first convert the observed data in 3D media, i.e., surface-wave empirical Green's functions (EGFs) from ambient noise cross-correlation, to the reconstructed EGFs in 2D media using a 3D/2D transformation scheme. Different from the conventional steps of measuring phase dispersion, the 2D adjoint tomography refines 2D shear wave speeds along the profile directly from the reconstructed Rayleigh wave EGFs in the period band 6-35s. With the 2D initial model extracted from the 3D model from traditional ambient noise tomography, adjoint tomography updates the model by minimizing the frequency-dependent Rayleigh wave traveltime misfits between the reconstructed EGFs and synthetic Green function (SGFs) in 2D media generated by the spectral-element method (SEM), with a preconditioned conjugate gradient method. The multitaper traveltime difference measurement is applied in four period bands during the inversion: 20-35s, 15-30s, 10-20s and 6-15s. The recovered model shows more detailed crustal structures with pronounced low velocity anomaly in the mid-lower crust beneath the junction of Taihang Mountains and Yin-Yan Mountains compared with the initial model. This low velocity structure may imply the possible intense crust-mantle interactions, probably associated with the magmatic underplating during the Mesozoic to Cenozoic evolution of the region. To our knowledge, it's first time that ambient noise adjoint tomography is implemented in 2D media. Considering the intensive computational cost and storage of 3D adjoint tomography, this 2D ambient noise adjoint tomography has potential advantages to get high-resolution 2D crustal structures with limited computational resource.

X-Ray Radiography of Gas Turbine Ceramics.

DTIC Science & Technology

1979-10-20

Microfocus X-ray equipment. 1a4ihe definition of equipment concepts for a computer assisted tomography ( CAT ) system; and 4ffthe development of a CAT ...were obtained from these test coupons using Microfocus X-ray and image en- hancement techniques. A Computer Assisted Tomography ( CAT ) design concept...monitor. Computer reconstruction algorithms were investigated with respect to CAT and a preferred approach was determined. An appropriate CAT algorithm

Spontaneous intracranial hemorrhage and multiple intracranial aneurysms in a patient with Roberts/SC phocomelia syndrome.

PubMed

Wang, Anthony C; Gemmete, Joseph J; Keegan, Catherine E; Witt, Cordelie E; Muraszko, Karin M; Than, Khoi D; Maher, Cormac O

2011-11-01

Roberts/SC phocomelia syndrome (RBS) is a rare but distinct genetic disorder with an autosomal recessive inheritance pattern. It has been associated with microcephaly, craniofacial malformation, cavernous hemangioma, encephalocele, and hydrocephalus. There are no previously reported cases of RBS with intracranial aneurysms. The authors report on a patient with a history of RBS who presented with a spontaneous posterior fossa hemorrhage. Multiple small intracranial aneurysms were noted on a preoperative CT angiogram. The patient underwent emergency craniotomy for evacuation of the hemorrhage. A postoperative angiogram confirmed the presence of multiple, distal small intracranial aneurysms.

RADIAL COMPUTED TOMOGRAPHY OF AIR CONTAMINANTS USING OPTICAL REMOTE SENSING

EPA Science Inventory

The paper describes the application of an optical remote-sensing (ORS) system to map air contaminants and locate fugitive emissions. Many ORD systems may utilize radial non-overlapping beam geometry and a computed tomography (CT) algorithm to map the concentrations in a plane. In...

Micro computed tomography (CT) scanned anatomical gateway to insect pest bioinformatics

USDA-ARS?s Scientific Manuscript database

An international collaboration to establish an interactive Digital Video Library for a Systems Biology Approach to study the Asian citrus Psyllid and psyllid genomics/proteomics interactions is demonstrated. Advances in micro-CT, digital computed tomography (CT) scan uses X-rays to make detailed pic...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

21 CFR 892.1200 - Emission computed tomography system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Emission computed tomography system. 892.1200 Section 892.1200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component...

A computer-aided system for automatic extraction of femur neck trabecular bone architecture using isotropic volume construction from clinical hip computed tomography images.

PubMed

Vivekanandhan, Sapthagirivasan; Subramaniam, Janarthanam; Mariamichael, Anburajan

2016-10-01

Hip fractures due to osteoporosis are increasing progressively across the globe. It is also difficult for those fractured patients to undergo dual-energy X-ray absorptiometry scans due to its complicated protocol and its associated cost. The utilisation of computed tomography for the fracture treatment has become common in the clinical practice. It would be helpful for orthopaedic clinicians, if they could get some additional information related to bone strength for better treatment planning. The aim of our study was to develop an automated system to segment the femoral neck region, extract the cortical and trabecular bone parameters, and assess the bone strength using an isotropic volume construction from clinical computed tomography images. The right hip computed tomography and right femur dual-energy X-ray absorptiometry measurements were taken from 50 south-Indian females aged 30-80 years. Each computed tomography image volume was re-constructed to form isotropic volumes. An automated system by incorporating active contour models was used to segment the neck region. A minimum distance boundary method was applied to isolate the cortical and trabecular bone components. The trabecular bone was enhanced and segmented using trabecular enrichment approach. The cortical and trabecular bone features were extracted and statistically compared with dual-energy X-ray absorptiometry measured femur neck bone mineral density. The extracted bone measures demonstrated a significant correlation with neck bone mineral density (r > 0.7, p < 0.001). The inclusion of cortical measures, along with the trabecular measures extracted after isotropic volume construction and trabecular enrichment approach procedures, resulted in better estimation of bone strength. The findings suggest that the proposed system using the clinical computed tomography images scanned with low dose could eventually be helpful in osteoporosis diagnosis and its treatment planning. © IMechE 2016.

Direct estimation of human trabecular bone stiffness using cone beam computed tomography.

PubMed

Klintström, Eva; Klintström, Benjamin; Pahr, Dieter; Brismar, Torkel B; Smedby, Örjan; Moreno, Rodrigo

2018-04-10

The aim of this study was to evaluate the possibility of estimating the biomechanical properties of trabecular bone through finite element simulations by using dental cone beam computed tomography data. Fourteen human radius specimens were scanned in 3 cone beam computed tomography devices: 3-D Accuitomo 80 (J. Morita MFG., Kyoto, Japan), NewTom 5 G (QR Verona, Verona, Italy), and Verity (Planmed, Helsinki, Finland). The imaging data were segmented by using 2 different methods. Stiffness (Young modulus), shear moduli, and the size and shape of the stiffness tensor were studied. Corresponding evaluations by using micro-CT were regarded as the reference standard. The 3-D Accuitomo 80 (J. Morita MFG., Kyoto, Japan) showed good performance in estimating stiffness and shear moduli but was sensitive to the choice of segmentation method. NewTom 5 G (QR Verona, Verona, Italy) and Verity (Planmed, Helsinki, Finland) yielded good correlations, but they were not as strong as Accuitomo 80 (J. Morita MFG., Kyoto, Japan). The cone beam computed tomography devices overestimated both stiffness and shear compared with the micro-CT estimations. Finite element-based calculations of biomechanics from cone beam computed tomography data are feasible, with strong correlations for the Accuitomo 80 scanner (J. Morita MFG., Kyoto, Japan) combined with an appropriate segmentation method. Such measurements might be useful for predicting implant survival by in vivo estimations of bone properties. Copyright © 2018 Elsevier Inc. All rights reserved.

Creation of a simple natural language processing tool to support an imaging utilization quality dashboard.

PubMed

Swartz, Jordan; Koziatek, Christian; Theobald, Jason; Smith, Silas; Iturrate, Eduardo

2017-05-01

Testing for venous thromboembolism (VTE) is associated with cost and risk to patients (e.g. radiation). To assess the appropriateness of imaging utilization at the provider level, it is important to know that provider's diagnostic yield (percentage of tests positive for the diagnostic entity of interest). However, determining diagnostic yield typically requires either time-consuming, manual review of radiology reports or the use of complex and/or proprietary natural language processing software. The objectives of this study were twofold: 1) to develop and implement a simple, user-configurable, and open-source natural language processing tool to classify radiology reports with high accuracy and 2) to use the results of the tool to design a provider-specific VTE imaging dashboard, consisting of both utilization rate and diagnostic yield. Two physicians reviewed a training set of 400 lower extremity ultrasound (UTZ) and computed tomography pulmonary angiogram (CTPA) reports to understand the language used in VTE-positive and VTE-negative reports. The insights from this review informed the arguments to the five modifiable parameters of the NLP tool. A validation set of 2,000 studies was then independently classified by the reviewers and by the tool; the classifications were compared and the performance of the tool was calculated. The tool was highly accurate in classifying the presence and absence of VTE for both the UTZ (sensitivity 95.7%; 95% CI 91.5-99.8, specificity 100%; 95% CI 100-100) and CTPA reports (sensitivity 97.1%; 95% CI 94.3-99.9, specificity 98.6%; 95% CI 97.8-99.4). The diagnostic yield was then calculated at the individual provider level and the imaging dashboard was created. We have created a novel NLP tool designed for users without a background in computer programming, which has been used to classify venous thromboembolism reports with a high degree of accuracy. The tool is open-source and available for download at http://iturrate.com/simpleNLP. Results obtained using this tool can be applied to enhance quality by presenting information about utilization and yield to providers via an imaging dashboard. Copyright © 2017 Elsevier B.V. All rights reserved.

Craniovertebral junction evaluation by computed tomography in asymptomatic individuals in the Indian population.

PubMed

Dash, Chinmaya; Singla, Raghav; Agarwal, Mohit; Kumar, Ambuj; Kumar, Hitesh; Mishra, Shashwat; Sharma, Bhawani S

2018-01-01

The available literature on the anatomy and imaging of the craniovertebral junction (CVJ) focusses on the osteometric indices described for the detection of abnormal relationships between the components of CVJ. However, a knowledge of the normal osteometry of this region in the Indian population is critically important for the operating surgeon as it may influence the surgical technique as well as the choice, size and configurations of the implants. It is also important to determine whether critical differences exist between the osteometric data of Indians and the rest of the world for this part of the anatomy. Accordingly, the present study is an attempt to quantitate the osteometric indices for the anatomically normal CVJ in Indian subjects. We retrospectively studied the imaging data of 49 consecutive adult patients (31 males, 18 females) who underwent a computed tomographic (CT) angiogram for suspected vascular conditions unrelated to the craniovertebral junction. Several parameters related to the atlanto-dental relationship, foramen magnum, atlas and axis vertebrae were recorded, including the dimensions of the commonly instrumented bony regions and also the indices related to the CVJ bony relationships. The data was also compared between the two genders, statistically through the Student's t-test using the statistical program "R". No patient had an atlanto dens interval >2.5 mm. The mean distance of the odontoid tip from the McRae line in this series was 5.11 mm and no patient had the odontoid tip above the McRae line. Female subjects had significantly smaller diameters of C1 lateral masses and odontoid screw trajectory length when compared to males. Additionally, in the Indian population, the length range of odontoid screw trajectory and the thickness of the narrowest part of the C2 pedicles was smaller with respect to similar data from other geographical regions. However, the rest of the parameters resembled the data from studies conducted on populations with other ethnicities. The osteometric parameters of the CVJ in the Indian population are largely similar to those described globally. However, there are some important differences too which can influence the design of surgical implants suited to the Indian population.

Positron emission tomography/computed tomography in melanoma.

PubMed

Bourgeois, Austin C; Chang, Ted T; Fish, Lindsay M; Bradley, Yong C

2013-09-01

Fludeoxyglucose F 18 positron emission tomography/computed tomography (PET/CT) has been invaluable in the assessment of melanoma throughout the course of the disease. As with any modality, the studies are incomplete and more information will be gleaned as our experience progresses. Additionally, it is hoped that a newer PET agent in the pipeline will give us even greater success in the identification and subsequent treatment of melanoma. This article aims to examine the utilization of PET/CT in the staging, prognostication, and follow-up of melanoma while providing the physicians who order and interpret these studies practical guidelines and interpretive pitfalls. Copyright © 2013 Elsevier Inc. All rights reserved.

Miscellaneous indications in bone scintigraphy: metabolic bone diseases and malignant bone tumors.

PubMed

Cook, Gary J R; Gnanasegaran, Gopinath; Chua, Sue

2010-01-01

The diphosphonate bone scan is ideally suited to assess many global, focal or multifocal metabolic bone disorders and there remains a role for conventional bone scintigraphy in metabolic bone disorders at diagnosis, investigation of complications, and treatment response assessment. In contrast, the role of bone scintigraphy in the evaluation of primary malignant bone tumors has reduced with the improvement of morphologic imaging, such as computed tomography and magnetic resonance imaging. However, an increasing role for (18)F-fluorodeoxyglucose positron emission tomography and positron emission tomography/computed tomography is emerging as a functional assessment at diagnosis, staging, and neoadjuvant treatment response assessment.

Usefulness of fluorodeoxyglucose positron emission tomography/computed tomography for detection of a neuroblastic nodule in a ganglioneuroblastoma: a case report.

PubMed

Takeda, Yuka; Sano, Hideki; Kawano, Asuka; Mochizuki, Kazuhiro; Takahashi, Nobuhisa; Kobayashi, Shogo; Ohara, Yoshihiro; Tasaki, Kazuhiro; Hosoya, Mitusuaki; Kikuta, Atsushi

2018-05-03

Ganglioneuroblastoma, nodular is defined as a composite tumor of biologically distinct clones. The peripheral neuroblastic tumors in this category are characterized by the presence of grossly visible neuroblastoma nodules coexisting with ganglioneuroblastoma, intermixed, or with ganglioneuroma. Making a correct diagnosis of ganglioneuroblastoma, nodular is often difficult by biopsy or partial tumor resection, because the neuroblastic nodule could be hidden and not sampled for pathological examination. We report a case of a Japanese boy aged 3 years, 8 months, with an unresectable abdominal tumor and elevated vanillylmandelic acid and homovanillic acid levels. The initial biopsy was ganglioneuroma. However, after the second biopsy from a hidden neuroblastoma nodule that was clearly highlighted by fluorodeoxyglucose positron emission tomography/computed tomography, we reached the diagnosis of ganglioneuroblastoma, nodular. Because the nodule demonstrated neuroblastoma, differentiating subtype, with a low mitosis-karyorrhexis index (favorable histology) and nonamplified MYCN, the boy was treated according to the intermediate-risk protocol and is now alive and well 4 years after the diagnosis. This case illustrates the critical role of fluorodeoxyglucose positron emission tomography/computed tomography for detecting a neuroblastoma nodule in a ganglioneuroblastoma.

FDG-PET/CT in the evaluation of anal carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cotter, Shane E.; Medical Scientist Training Program, Washington University School of Medicine, St. Louis, MO; Grigsby, Perry W.

2006-07-01

Purpose: Surgical staging and treatment of anal carcinoma has been replaced by noninvasive staging studies and combined modality therapy. In this study, we compare computed tomography (CT) and physical examination to [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) in the staging of carcinoma of the anal canal, with special emphasis on determination of spread to inguinal lymph nodes. Methods and Materials: Between July 2003 and July 2005, 41 consecutive patients with biopsy-proved anal carcinoma underwent a complete staging evaluation including physical examination, CT, and 2-FDG-PET/CT. Patients ranged in age from 30 to 89 years. Nine men were HIV-positive. Treatment was withmore » standard Nigro regimen. Results: [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) detected 91% of nonexcised primary tumors, whereas CT visualized 59%. FDG-PET/CT detected abnormal uptake in pelvic nodes of 5 patients with normal pelvic CT scans. FDG-PET/CT detected abnormal nodes in 20% of groins that were normal by CT, and in 23% without abnormality on physical examination. Furthermore, 17% of groins negative by both CT and physical examination showed abnormal uptake on FDG-PET/CT. HIV-positive patients had an increased frequency of PET-positive lymph nodes. Conclusion: [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography detects the primary tumor more often than CT. FDG-PET/CT detects substantially more abnormal inguinal lymph nodes than are identified by standard clinical staging with CT and physical examination.« less

Segmenting root systems in xray computed tomography images using level sets

USDA-ARS?s Scientific Manuscript database

The segmentation of plant roots from soil and other growing mediums in xray computed tomography images is needed to effectively study the shapes of roots without excavation. However, segmentation is a challenging problem in this context because the root and non-root regions share similar features. ...

Retroperitoneal tumour radiotherapy: clinical improvements using kilovoltage cone beam computed tomography.

PubMed

Juan-Senabre, Xavier J; Ferrer-Albiach, Carlos; Rodríguez-Cordón, Marta; Santos-Serra, Agustín; López-Tarjuelo, Juan; Calzada-Feliu, Salvador

2009-04-01

We present a clinical case of a patient diagnosed with a retroperitoneal sarcoma, which received preoperative treatment with daily verification via computed tomography obtained with kilovoltage cone beam. We compare the benefit of this treatment compared to other conventional treatment without image guiding, reporting quantitative results.

Imaging Techniques in Endodontics: An Overview

PubMed Central

Deepak, B. S.; Subash, T. S.; Narmatha, V. J.; Anamika, T.; Snehil, T. K.; Nandini, D. B.

2012-01-01

This review provides an overview of the relevance of imaging techniques such as, computed tomography, cone beam computed tomography, and ultrasound, to endodontic practice. Many limitations of the conventional radiographic techniques have been overcome by the newer methods. Advantages and disadvantages of various imaging techniques in endodontic practice are also discussed. PMID:22530184

SIMULATION STUDY FOR GASEOUS FLUXES FROM AN AREA SOURCE USING COMPUTED TOMOGRAPHY AND OPTICAL REMOTE SENSING

EPA Science Inventory

The paper presents a new approach to quantifying emissions from fugitive gaseous air pollution sources. Computed tomography (CT) and path-integrated optical remote sensing (PI-ORS) concentration data are combined in a new field beam geometry. Path-integrated concentrations are ...

Computed tomography as a diagnostic aid for extracanal invasive resorption.

PubMed

Kim, Euiseong; Kim, Kee-Deog; Roh, Byoung-Duck; Cho, Yong-Sik; Lee, Seung-Jong

2003-07-01

A case of multiple extracanal invasive resorption is reported. The patient had a history of hypothyroidism for approximately 1 yr before the dental visit. Utilization of computed tomography and a rapid prototyping tooth model in diagnosing the exact location and the size of the resorption area are discussed.

Single photon emission computed tomography in motor neuron disease with dementia.

PubMed

Sawada, H; Udaka, F; Kishi, Y; Seriu, N; Mezaki, T; Kameyama, M; Honda, M; Tomonobu, M

1988-01-01

Single photon emission computed tomography with [123 I] isopropylamphetamine was carried out on a patient with motor neuron disease with dementia. [123 I] uptake was decreased in the frontal lobes. This would reflect the histopathological findings such as neuronal loss and gliosis in the frontal lobes.

APPLICATION OF 3D COMPUTER-AIDED TOMOGRAPHY TO THE QUANTIFICATION OF MARINE SEDIMENT COMMUNITIES IN POLLUTION GRADIENTS

EPA Science Inventory

Computer-Aided Tomography (CT) has been demonstrated to be a cost efficient tool for the qualitative and quantitative study of estuarine benthic communities along pollution gradients.
Now we have advanced this technology to successfully visualize and discriminate three dimen...

Spatial image modulation to improve performance of computed tomography imaging spectrometer

NASA Technical Reports Server (NTRS)

Bearman, Gregory H. (Inventor); Wilson, Daniel W. (Inventor); Johnson, William R. (Inventor)

2010-01-01

Computed tomography imaging spectrometers ("CTIS"s) having patterns for imposing spatial structure are provided. The pattern may be imposed either directly on the object scene being imaged or at the field stop aperture. The use of the pattern improves the accuracy of the captured spatial and spectral information.

Advanced imaging in COPD: insights into pulmonary pathophysiology

PubMed Central

Milne, Stephen

2014-01-01

Chronic obstructive pulmonary disease (COPD) involves a complex interaction of structural and functional abnormalities. The two have long been studied in isolation. However, advanced imaging techniques allow us to simultaneously assess pathological processes and their physiological consequences. This review gives a comprehensive account of the various advanced imaging modalities used to study COPD, including computed tomography (CT), magnetic resonance imaging (MRI), and the nuclear medicine techniques positron emission tomography (PET) and single-photon emission computed tomography (SPECT). Some more recent developments in imaging technology, including micro-CT, synchrotron imaging, optical coherence tomography (OCT) and electrical impedance tomography (EIT), are also described. The authors identify the pathophysiological insights gained from these techniques, and speculate on the future role of advanced imaging in both clinical and research settings. PMID:25478198

Viewing Welds By Computer Tomography

NASA Technical Reports Server (NTRS)

Pascua, Antonio G.; Roy, Jagatjit

1990-01-01

Computer tomography system used to inspect welds for root penetration. Source illuminates rotating welded part with fan-shaped beam of x rays or gamma rays. Detectors in circular array on opposite side of part intercept beam and convert it into electrical signals. Computer processes signals into image of cross section of weld. Image displayed on video monitor. System offers only nondestructive way to check penetration from outside when inner surfaces inaccessible.

Comparison of computed tomography with radiography as a noninvasive diagnostic technique for chronic nasal disease in dogs.

PubMed

Codner, E C; Lurus, A G; Miller, J B; Gavin, P R; Gallina, A; Barbee, D D

1993-04-01

Computed tomography was evaluated as a noninvasive technique for the diagnosis of chronic nasal disease in dogs. Computed tomographic images, radiographs, and histopathologic findings were compared in 11 dogs with chronic nasal disease. Definitive diagnosis was made following traumatic nasal flush, exploratory surgery, or necropsy. The study included 8 dogs with intranasal tumors, 2 dogs with bacterial rhinitis (Pasteurella sp), and 1 dog with mycotic rhinitis (Aspergillus sp). Computed tomography was superior to radiography in defining the extent of the disease process and in differentiating infectious rhinitis from nasal neoplasms. It defined lesions in the palate, nasopharyngeal meatus, maxillary sinus, caudal ethmoturbinates, and periorbital tissues that were difficult to demonstrate by use of conventional radiography. Tumors appeared as space-occupying lesions that obliterated the turbinates, caused deviation of the nasal septum, and eroded bone. Rhinitis appeared as a cavitating lesion that spared the paranasal sinuses, thickened and distorted the turbinates, and widened the meatus. Although morphologically distinct on computed tomographic images, infectious rhinitis and nasal neoplasms could not be differentiated by attenuation measurements or degree of contrast enhancement. Computed tomography appeared to be a reliable, noninvasive technique for the diagnosis of chronic nasal disease in dogs, and a promising alternative to diagnostic techniques currently in use.

[CONE BEAM COMPUTED TOMOGRAPHY IN DIAGNOSTICS OF ODONTOGENIC MAXILLARY SINUSITIS (CASE REPORTS)].

PubMed

Demidova, E; Khurdzidze, G

2017-06-01

Diagnostic studies performed by cone beam computed tomography Morita 3D made possible to obtain high resolution images of hard tissues of upper jawbone and maxillary sinus, to detect bony tissue defects, such as odontogenic cysts, cystogranulomas and granulomas. High-resolution and three dimensional tomographic image reconstructions allowed for optimal and prompt determination of the scope of surgical treatment and planning of effective conservative treatment regimen. Interactive diagnostics helped to estimate cosmetic and functional results of surgical treatment, to prevent the occurrence of surgical complications, and to evaluate the efficacy of conservative treatment. The obtained data contributed to determination of particular applications of cone beam computed tomography in the diagnosis of odontogenic maxillary sinusitis, detection of specific defects with cone beam tomography as the most informative method of diagnosis; as well as to determination of weak and strong sides, and helped to offer mechanisms of x-ray diagnostics to dental surgeons and ENT specialists.

Dynamic contrast enhanced CT in nodule characterization: How we review and report.

PubMed

Qureshi, Nagmi R; Shah, Andrew; Eaton, Rosemary J; Miles, Ken; Gilbert, Fiona J

2016-07-18

Incidental indeterminate solitary pulmonary nodules (SPN) that measure less than 3 cm in size are an increasingly common finding on computed tomography (CT) worldwide. Once identified there are a number of imaging strategies that can be performed to help with nodule characterization. These include interval CT, dynamic contrast enhanced computed tomography (DCE-CT), (18)F-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG-PET-CT). To date the most cost effective and efficient non-invasive test or combination of tests for optimal nodule characterization has yet to be determined.DCE-CT is a functional test that involves the acquisition of a dynamic series of images of a nodule before and following the administration of intravenous iodinated contrast medium. This article provides an overview of the current indications and limitations of DCE- CT in nodule characterization and a systematic approach to how to perform, analyse and interpret a DCE-CT scan.

Thrombus Formation After Percutaneous Catheterization and Manual Compression of the Femoral Artery in Heparinized Sheep

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Young Hwan; Pavcnik, Dusan, E-mail: pavcnikd@ohsu.edu; Kakizawa, Hideyaki

The purpose of this study was to evaluate the angiographic and histopathologic changes in the superficial femoral artery (SFA) in heparinized sheep shortly after catheterization with an 8-Fr sheath and manual compression hemostasis either with standard manual compression (SMC) or with the use of a procoagulant chitosan-based HemCon Bandage. The evaluation was done in 38 SFAs of 19 heparinized (100 mg/kg) sheep. After a 5-min catheterization with an 8-Fr sheath, a 5-min compression was applied. Follow-up angiograms to evaluate hemostasis were done immediately after release of compression and then at 2.5-min intervals until no extravasation was present. Compression was reappliedmore » between angiograms. Final angiograms were performed approximately 30 min after hemostasis and after 3 min of passive flexion and extension of sheep hind limbs. Sheep were then euthanized and SFA specimens with surrounding tissues excised for histopathologic evaluation. Both types of compression caused similar changes in the catheterized SFAs. Follow-up angiograms showed mild arterial narrowing in 14 SFAs and intraluminal clots in 9 SFAs. Histology revealed periarterial hematoma in all 38 specimens. Intraluminal thrombi consisting predominantly of platelets and fibrin were present in 32 SFAs. Their size varied from superficial elevations (8 arteries) to medium-sized, 1- to 2-mm, polypoid protrusions (15 arteries) to large polypoid clots, 3-4 mm long (9 arteries). In six SFAs, the arterial access sites were not included in the obtained specimens. In conclusion, hemostasis with manual compression is achieved in the acute phase by formation of a predominantly platelet-fibrin thrombus occluding the arterial wall access site and often extending significantly into the arterial lumen. The healing process of arterial access sites should be explored several days after catheterization.« less

Magnetic resonance fingerprinting based on realistic vasculature in mice.

PubMed

Pouliot, Philippe; Gagnon, Louis; Lam, Tina; Avti, Pramod K; Bowen, Chris; Desjardins, Michèle; Kakkar, Ashok K; Thorin, Eric; Sakadzic, Sava; Boas, David A; Lesage, Frédéric

2017-04-01

Magnetic resonance fingerprinting (MRF) was recently proposed as a novel strategy for MR data acquisition and analysis. A variant of MRF called vascular MRF (vMRF) followed, that extracted maps of three parameters of physiological importance: cerebral oxygen saturation (SatO 2 ), mean vessel radius and cerebral blood volume (CBV). However, this estimation was based on idealized 2-dimensional simulations of vascular networks using random cylinders and the empirical Bloch equations convolved with a diffusion kernel. Here we focus on studying the vascular MR fingerprint using real mouse angiograms and physiological values as the substrate for the MR simulations. The MR signal is calculated ab initio with a Monte Carlo approximation, by tracking the accumulated phase from a large number of protons diffusing within the angiogram. We first study the identifiability of parameters in simulations, showing that parameters are fully estimable at realistically high signal-to-noise ratios (SNR) when the same angiogram is used for dictionary generation and parameter estimation, but that large biases in the estimates persist when the angiograms are different. Despite these biases, simulations show that differences in parameters remain estimable. We then applied this methodology to data acquired using the GESFIDE sequence with SPIONs injected into 9 young wild type and 9 old atherosclerotic mice. Both the pre injection signal and the ratio of post-to-pre injection signals were modeled, using 5-dimensional dictionaries. The vMRF methodology extracted significant differences in SatO 2 , mean vessel radius and CBV between the two groups, consistent across brain regions and dictionaries. Further validation work is essential before vMRF can gain wider application. Copyright © 2017 Elsevier Inc. All rights reserved.

Dynamical relations for left ventricular ejection - Flow rate, momentum, force and impulse

NASA Technical Reports Server (NTRS)

Back, L. H.; Selzer, R. H.; Gordon, D. G.; Ledbetter, D. C.; Crawford, D. W.

1984-01-01

An investigation was carried out to quantitatively evaluate left ventricular volume flow rate, momentum, force and impulse derived from application of conservation principles for mass and momentum of blood within the ventricle during the ejection phase. An automated digital image processing system was developed and applied to left ventricular angiograms which are computer processed and analyzed frame by frame to determine the dynamical relations by numerical methods. The initial experience with force and impulse has indicated that neither quantity seemed to be a sensitive indicator of coronary artery disease as evaluated by qualitative angiography for the particular patient group studied. Utilization of the dynamical relations in evaluating human left ventricular performance requires improved means of measurement and interpretation of clinical studies.

Imaging ischemic strokes in rodents using visible-light optical coherence tomography (Conference Presentation)

NASA Astrophysics Data System (ADS)

Chen, Siyu; Liu, Qi; Shu, Xiao; Soetikno, Brian T.; Tong, Shanbao; Zhang, Hao F.

2017-02-01

Monitoring cortical hemodynamic response after ischemic stroke (IS) is essential for understanding the pathophysiological mechanisms behind IS-induced neuron loss. Functional optical coherence tomography (OCT) is an emerging technology that can fulfill the requirement, providing label-free, high-resolution 3D images of cerebral hemodynamics. Unfortunately, strong tissue scattering pose a significant challenge for existing OCT oximetry techniques, as they either ignore the effect or compensate it numerically. Here we developed a novel dual-depth sampling and normalization strategy using visible-light OCT (vis-OCT) angiograms that can provide robust and precise sO2 estimations within cerebral circulation. The related theoretical formulation were established, and its implication and limitations were discussed. We monitored mouse cortical hemodynamics using the newly-developed method. Focal ischemic stroke was induced through photothrombosis. The analysis on pre- and post-IS vis-OCT images revealed both vascular morphology and oxygenation altered substantially after the occlusion. First, the ischemic core could be clearly identified as angiographic intensity fell below the detection limit. In addition, vessel dilation presented universally in the penumbra region. Notably for pial arteriles, the percentage of increase demonstrated inverse relationship with their pre-occlusion, pre-dilation dimeter. Vis-OCT oxygenation maps on intact cortex revealed spatial sO2 variations within pial vessels. Specifically, sO2 in arterioles decreased as it bifurcated and plunged into deeper tissue. Similarly, venous sO2 was higher in the larger, more superficial pial brunches. However, such difference was no longer appreciable after photothrombosis. Averaged arteriole sO2 dropped to 64% - 67% in the penumbra region.

Automated Quantitative Analysis of Retinal Microvasculature in Normal Eyes on Optical Coherence Tomography Angiography.

PubMed

Lupidi, Marco; Coscas, Florence; Cagini, Carlo; Fiore, Tito; Spaccini, Elisa; Fruttini, Daniela; Coscas, Gabriel

2016-09-01

To describe a new automated quantitative technique for displaying and analyzing macular vascular perfusion using optical coherence tomography angiography (OCT-A) and to determine a normative data set, which might be used as reference in identifying progressive changes due to different retinal vascular diseases. Reliability study. A retrospective review of 47 eyes of 47 consecutive healthy subjects imaged with a spectral-domain OCT-A device was performed in a single institution. Full-spectrum amplitude-decorrelation angiography generated OCT angiograms of the retinal superficial and deep capillary plexuses. A fully automated custom-built software was used to provide quantitative data on the foveal avascular zone (FAZ) features and the total vascular and avascular surfaces. A comparative analysis between central macular thickness (and volume) and FAZ metrics was performed. Repeatability and reproducibility were also assessed in order to establish the feasibility and reliability of the method. The comparative analysis between the superficial capillary plexus and the deep capillary plexus revealed a statistically significant difference (P < .05) in terms of FAZ perimeter, surface, and major axis and a not statistically significant difference (P > .05) when considering total vascular and avascular surfaces. A linear correlation was demonstrated between central macular thickness (and volume) and the FAZ surface. Coefficients of repeatability and reproducibility were less than 0.4, thus demonstrating high intraobserver repeatability and interobserver reproducibility for all the examined data. A quantitative approach on retinal vascular perfusion, which is visible on Spectralis OCT angiography, may offer an objective and reliable method for monitoring disease progression in several retinal vascular diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparative study of cranial anthropometric measurement by traditional calipers to computed tomography and three-dimensional photogrammetry.

PubMed

Mendonca, Derick A; Naidoo, Sybill D; Skolnick, Gary; Skladman, Rachel; Woo, Albert S

2013-07-01

Craniofacial anthropometry by direct caliper measurements is a common method of quantifying the morphology of the cranial vault. New digital imaging modalities including computed tomography and three-dimensional photogrammetry are similarly being used to obtain craniofacial surface measurements. This study sought to compare the accuracy of anthropometric measurements obtained by calipers versus 2 methods of digital imaging.Standard anterior-posterior, biparietal, and cranial index measurements were directly obtained on 19 participants with an age range of 1 to 20 months. Computed tomographic scans and three-dimensional photographs were both obtained on each child within 2 weeks of the clinical examination. Two analysts measured the anterior-posterior and biparietal distances on the digital images. Measures of reliability and bias between the modalities were calculated and compared.Caliper measurements were found to underestimate the anterior-posterior and biparietal distances as compared with those of the computed tomography and the three-dimensional photogrammetry (P < 0.001). Cranial index measurements between the computed tomography and the calipers differed by up to 6%. The difference between the 2 modalities was statistically significant (P = 0.021). The biparietal and cranial index results were similar between the digital modalities, but the anterior-posterior measurement was greater with the three-dimensional photogrammetry (P = 0.002). The coefficients of variation for repeated measures based on the computed tomography and the three-dimensional photogrammetry were 0.008 and 0.007, respectively.In conclusion, measurements based on digital modalities are generally reliable and interchangeable. Caliper measurements lead to underestimation of anterior-posterior and biparietal values compared with digital imaging.

Imaging of a parapharyngeal hemangiopericytoma. Radioimmunoscintigraphy (SPECT) with indium-111-labeled anti-CEA antibody, and comparison to digital subtraction angiography, computed tomography, and immunohistochemistry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kairemo, K.J.; Hopsu, E.V.; Melartin, E.J.

1991-01-01

A 27-year-old male patient with a parapharyngeal hemangiopericytoma was investigated radiologically with orthopantomography, computed tomography, and digital subtraction angiography before the operation. Because a malignancy was suspected, the patient was imaged with gamma camera using radiolabeled monoclonal anticarcinoembryonal antigen antibody including single photon emission computed tomography. The radioantibody accumulated strongly into the neoplasm. Tumor to background ratio was 2.2. Samples of the excised tumor were stained immunohistochemically for desmin, vimentin, muscle actin, cytokeratin, CEA (carcinoembryonic antigen), and factor VIII. They showed that the antibody uptake was of unspecific nature and not due to CEA expression in the tumor.

Normal Variants and Pitfalls Encountered in PET Assessment of Gynecologic Malignancies.

PubMed

Yu, Jian Q; Doss, Mohan; Alpaugh, R Katherine

2018-04-01

Combined PET/computed tomography is used for oncological indications. PET/computed tomography benefits from the metabolic information of PET and the anatomic localization of computed tomography. The integrated scanner provides data with accurate registration of anatomy and molecular information. Many physiologic conditions, normal variants, and benign lesions within the pelvis and the body can cause confusion and uncertainty. False-negative results owing to low 18 F-fluorodeoxyglucose uptake from the tumor can produce diagnostic challenges and inaccurate conclusions. This article reviews normal variants and potential pitfalls encountered in PET assessment of gynecologic malignancies to provide useful information for the referring and reporting physicians. Copyright © 2017 Elsevier Inc. All rights reserved.

Computed Tomography and Thermography Increases CMC Material and Process Development Efficiency and Testing Effectiveness

NASA Technical Reports Server (NTRS)

Effinger, Michael; Beshears, Ron; Hufnagle, David; Walker, James; Russell, Sam; Stowell, Bob; Myers, David

2002-01-01

Nondestructive characterization techniques have been used to steer development and testing of CMCs. Computed tomography is used to determine the volumetric integrity of the CMC plates and components. Thermography is used to determine the near surface integrity of the CMC plates and components. For process and material development, information such as density uniformity, part delamination, and dimensional tolerance conformity is generated. The information from the thermography and computed tomography is correlated and then specimen cutting maps are superimposed on the thermography images. This enables for tighter data and potential explanation of off nominal test data. Examples of nondestructive characterization utilization to make decisions in process and material development and testing are presented.

UNSEDATED COMPUTED TOMOGRAPHY FOR DIAGNOSIS OF PELVIC CANAL OBSTRUCTION IN A LEOPARD GECKO (EUBLEPHARIS MACULARIUS).

PubMed

DeCourcy, Kelly; Hostnik, Eric T; Lorbach, Josh; Knoblaugh, Sue

2016-12-01

An adult leopard gecko ( Eublepharis macularius ) presented for lethargy, hyporexia, weight loss, decreased passage of waste, and a palpable caudal coelomic mass. Computed tomography showed a heterogeneous hyperattenuating (∼143 Hounsfield units) structure within the right caudal coelom. The distal colon-coprodeum lumen or urinary bladder was hypothesized as the most likely location for the heterogeneous structure. Medical support consisted of warm water and lubricant enema, as well as a heated environment. Medical intervention aided the passage of a plug comprised centrally of cholesterol and urates with peripheral stratified layers of fibrin, macrophages, heterophils, and bacteria. Within 24 hr, a follow-up computed tomography scan showed resolution of the pelvic canal plug.

Diffraction scattering computed tomography: a window into the structures of complex nanomaterials

PubMed Central

Birkbak, M. E.; Leemreize, H.; Frølich, S.; Stock, S. R.

2015-01-01

Modern functional nanomaterials and devices are increasingly composed of multiple phases arranged in three dimensions over several length scales. Therefore there is a pressing demand for improved methods for structural characterization of such complex materials. An excellent emerging technique that addresses this problem is diffraction/scattering computed tomography (DSCT). DSCT combines the merits of diffraction and/or small angle scattering with computed tomography to allow imaging the interior of materials based on the diffraction or small angle scattering signals. This allows, e.g., one to distinguish the distributions of polymorphs in complex mixtures. Here we review this technique and give examples of how it can shed light on modern nanoscale materials. PMID:26505175

Evaluation of dosimetry and image of very low-dose computed tomography attenuation correction for pediatric positron emission tomography/computed tomography: phantom study

NASA Astrophysics Data System (ADS)

Bahn, Y. K.; Park, H. H.; Lee, C. H.; Kim, H. S.; Lyu, K. Y.; Dong, K. R.; Chung, W. K.; Cho, J. H.

2014-04-01

In this study, phantom was used to evaluate attenuation correction computed tomography (CT) dose and image in case of pediatric positron emission tomography (PET)/CT scan. Three PET/CT scanners were used along with acryl phantom in the size for infant and ion-chamber dosimeter. The CT image acquisition conditions were changed from 10 to 20, 40, 80, 100 and 160 mA and from 80 to 100, 120 and 140 kVp, which aimed at evaluating penetrate dose and computed tomography dose indexvolume (CTDIvol) value. And NEMA PET Phantom™ was used to obtain PET image under the same CT conditions in order to evaluate each attenuation-corrected PET image based on standard uptake value (SUV) value and signal-to-noise ratio (SNR). In general, the penetrate dose was reduced by around 92% under the minimum CT conditions (80 kVp and 10 mA) with the decrease in CTDIvol value by around 88%, compared with the pediatric abdomen CT conditions (100 kVp and 100 mA). The PET image with its attenuation corrected according to each CT condition showed no change in SUV value and no influence on the SNR. In conclusion, if the minimum dose CT that is properly applied to body of pediatric patient is corrected for attenuation to ensure that the effective dose is reduced by around 90% or more compared with that for adult patient, this will be useful to reduce radiation exposure level.

Fusion Imaging: A Novel Staging Modality in Testis Cancer

PubMed Central

Sterbis, Joseph R.; Rice, Kevin R.; Javitt, Marcia C.; Schenkman, Noah S.; Brassell, Stephen A.

2010-01-01

Objective: Computed tomography and chest radiographs provide the standard imaging for staging, treatment, and surveillance of testicular germ cell neoplasms. Positron emission tomography has recently been utilized for staging, but is somewhat limited in its ability to provide anatomic localization. Fusion imaging combines the metabolic information provided by positron emission tomography with the anatomic precision of computed tomography. To the best of our knowledge, this represents the first study of the effectiveness using fusion imaging in evaluation of patients with testis cancer. Methods: A prospective study of 49 patients presenting to Walter Reed Army Medical Center with testicular cancer from 2003 to 2009 was performed. Fusion imaging was compared with conventional imaging, tumor markers, pathologic results, and clinical follow-up. Results: There were 14 true positives, 33 true negatives, 1 false positive, and 1 false negative. Sensitivity, specificity, positive predictive value, and negative predictive value were 93.3, 97.0, 93.3, and 97.0% respectively. In 11 patient scenarios, fusion imaging differed from conventional imaging. Utility was found in superior lesion detection compared to helical computed tomography due to anatomical/functional image co-registration, detection of micrometastasis in lymph nodes (pathologic nodes < 1cm), surveillance for recurrence post-chemotherapy, differentiating fibrosis from active disease in nodes < 2.5cm, and acting as a quality assurance measure to computed tomography alone. Conclusions: In addition to demonstrating a sensitivity and specificity comparable or superior to conventional imaging, fusion imaging shows promise in providing additive data that may assist in clinical decision-making. PMID:21103077

Fusion imaging: a novel staging modality in testis cancer.

PubMed

Sterbis, Joseph R; Rice, Kevin R; Javitt, Marcia C; Schenkman, Noah S; Brassell, Stephen A

2010-11-05

Computed tomography and chest radiographs provide the standard imaging for staging, treatment, and surveillance of testicular germ cell neoplasms. Positron emission tomography has recently been utilized for staging, but is somewhat limited in its ability to provide anatomic localization. Fusion imaging combines the metabolic information provided by positron emission tomography with the anatomic precision of computed tomography. To the best of our knowledge, this represents the first study of the effectiveness using fusion imaging in evaluation of patients with testis cancer. A prospective study of 49 patients presenting to Walter Reed Army Medical Center with testicular cancer from 2003 to 2009 was performed. Fusion imaging was compared with conventional imaging, tumor markers, pathologic results, and clinical follow-up. There were 14 true positives, 33 true negatives, 1 false positive, and 1 false negative. Sensitivity, specificity, positive predictive value, and negative predictive value were 93.3, 97.0, 93.3, and 97.0% respectively. In 11 patient scenarios, fusion imaging differed from conventional imaging. Utility was found in superior lesion detection compared to helical computed tomography due to anatomical/functional image co-registration, detection of micrometastasis in lymph nodes (pathologic nodes < 1cm), surveillance for recurrence post-chemotherapy, differentiating fibrosis from active disease in nodes < 2.5cm, and acting as a quality assurance measure to computed tomography alone. In addition to demonstrating a sensitivity and specificity comparable or superior to conventional imaging, fusion imaging shows promise in providing additive data that may assist in clinical decision-making.

Computational adaptive optics for broadband interferometric tomography of tissues and cells

NASA Astrophysics Data System (ADS)

Adie, Steven G.; Mulligan, Jeffrey A.

2016-03-01

Adaptive optics (AO) can shape aberrated optical wavefronts to physically restore the constructive interference needed for high-resolution imaging. With access to the complex optical field, however, many functions of optical hardware can be achieved computationally, including focusing and the compensation of optical aberrations to restore the constructive interference required for diffraction-limited imaging performance. Holography, which employs interferometric detection of the complex optical field, was developed based on this connection between hardware and computational image formation, although this link has only recently been exploited for 3D tomographic imaging in scattering biological tissues. This talk will present the underlying imaging science behind computational image formation with optical coherence tomography (OCT) -- a beam-scanned version of broadband digital holography. Analogous to hardware AO (HAO), we demonstrate computational adaptive optics (CAO) and optimization of the computed pupil correction in 'sensorless mode' (Zernike polynomial corrections with feedback from image metrics) or with the use of 'guide-stars' in the sample. We discuss the concept of an 'isotomic volume' as the volumetric extension of the 'isoplanatic patch' introduced in astronomical AO. Recent CAO results and ongoing work is highlighted to point to the potential biomedical impact of computed broadband interferometric tomography. We also discuss the advantages and disadvantages of HAO vs. CAO for the effective shaping of optical wavefronts, and highlight opportunities for hybrid approaches that synergistically combine the unique advantages of hardware and computational methods for rapid volumetric tomography with cellular resolution.

Asymptomatic Emphysematous Pyelonephritis - Positron Emission Tomography Computerized Tomography Aided Diagnostic and Therapeutic Elucidation

PubMed Central

Pathapati, Deepti; Shinkar, Pawan Gulabrao; kumar, Satya Awadhesh; Jha; Dattatreya, Palanki Satya; Chigurupati, Namrata; Chigurupati, Mohana Vamsy; Rao, Vatturi Venkata Satya Prabhakar

2017-01-01

The authors report an interesting coincidental unearthing by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) of a potentially serious medical condition of emphysematous pyelonephritis in a case of nasopharyngeal carcinoma. The management by conservative ureteric stenting and antibiotics was done with gratifying clinical outcome. PMID:28242985

[Multispiral computed tomographic semiotics of laryngeal cancer].

PubMed

Vasil'ev, P V; Iudin, A L; Sdvizhkov, A M; Kozhanov, L G

2007-01-01

Multispiral computed tomography (MSCT) with intravenous bolus contrasting is a currently available method for radiodiagnosis of laryngeal cancer. MSCT is of much higher informative value in estimating the extent of a tumorous lesion than the traditional radiodiagnostic techniques: linear tomography, lateral X-ray study, roentgenoscopy and roentgenography of the laryngopharynx and esophagus with barium meal.

Diffuse cylindrical bronchiectasis due to eosinophilic bronchopneumopathy in a dog

PubMed Central

Meler, Erika; Pressler, Barrak M.; Heng, Hock Gan; Baird, Debra K.

2010-01-01

A miniature pinscher-cross was evaluated for chronic coughing. Computed tomography and bronchoscopy revealed severe, diffuse, cylindrical bronchiectasis secondary to eosinophilic bronchopneumopathy. Computed tomography is the gold standard for diagnosis of bronchiectasis in humans, and should be further investigated in dogs as a means of characterizing severity and pattern of disease. PMID:20885829

Abernethy malformation with portal vein aneurysm in a child.

PubMed

Chandrashekhara, Sheragaru H; Bhalla, Ashu Seith; Gupta, Arun Kumar; Vikash, C S; Kabra, Susheel Kumar

2011-01-01

Abernethy malformation is an extremely rare anomaly of the splanchnic venous system. We describe multidetector computed tomography findings of an incidentally detected Abernethy malformation with portal vein aneurysm in a two-and-half-year old child. The computed tomography scan was performed for the evaluation of respiratory distress, poor growth, and loss of appetite.

Computed tomography guided localization of clinically occult breast carcinoma-the ''N'' skin guide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kopans, D.B.; Meyer, J.E.

1982-10-01

Standard computed tomography (CT) can be used for the three-dimensional localization of clinically occult suspicious breast lesions whose exact position cannot be determined by standard mammographic views. A method is described that facilitates accurate preoperative needle localization using CT guidance, once the position of these lesions is defined.

Presence of gas in left ventricle due to infective endocarditis.

PubMed

Laiq, Zenab; Yarmohammadi, Hirad; Nabeel, Yassar; Adatya, Sirtaz

2016-01-01

Gas in myocardium is a rare manifestation of infective endocarditis caused by gas producing bacteria. We present a case of infective endocarditis caused by Citrobacter Koseri initially diagnosed by computed tomography and confirmed with transesophageal echocardiogram. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

21 CFR 892.1750 - Computed tomography x-ray system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Computed tomography x-ray system. 892.1750 Section 892.1750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... same axial plane taken at different angles. This generic type of device may include signal analysis and...

Use of Computed Tomography Imaging for Qualifying Coarse Roots, Rhizomes, Peat, and Particle Densities in Marsh Soils

EPA Science Inventory

Computed tomography (CT) imaging has been used to describe and quantify subtidal, benthic animals such as polychaetes, amphipods, and shrimp. Here, for the first time, CT imaging is used to successfully quantify wet mass of coarse roots, rhizomes, and peat in cores collected from...

Use of Computer-Aided Tomography (CT) Imaging for Quantifying Coarse Roots, Rhizomes, Peat, and Particle Densities in Marsh Soils

EPA Science Inventory

Computer-aided Tomography (CT) imaging was utilized to quantify wet mass of coarse roots, rhizomes, and peat in cores collected from organic-rich (Jamaica Bay, NY) and mineral (North Inlet, SC) Spartina alterniflora soils. Calibration rods composed of materials with standard dens...

APPLICATION OF COMPUTER-AIDED TOMOGRAPHY TO VISUALIZE AND QUANTIFY BIOGENIC STRUCTURES IN MARINE SEDIMENTS

EPA Science Inventory

We used computer-aided tomography (CT) for 3D visualization and 2D analysis of

marine sediment cores from 3 stations (at 10, 75 and 118 m depths) with different environmental

impact. Biogenic structures such as tubes and burrows were quantified and compared among st...

Micro-computed tomography of pupal metamorphosis in the solitary bee Megachile rotundata

USDA-ARS?s Scientific Manuscript database

Insect metamorphosis involves a complex change in form and function, but most of these changes are internal and treated as a black box. In this study, we examined development of the solitary bee, Megachile rotundata, using micro-computed tomography (µCT) and digital volume analysis. We describe deve...

Reliability of voxel gray values in cone beam computed tomography for preoperative implant planning assessment.

PubMed

Parsa, Azin; Ibrahim, Norliza; Hassan, Bassam; Motroni, Alessandro; van der Stelt, Paul; Wismeijer, Daniel

2012-01-01

To assess the reliability of cone beam computed tomography (CBCT) voxel gray value measurements using Hounsfield units (HU) derived from multislice computed tomography (MSCT) as a clinical reference (gold standard). Ten partially edentulous human mandibular cadavers were scanned by two types of computed tomography (CT) modalities: multislice CT and cone beam CT. On MSCT scans, eight regions of interest (ROI) designating the site for preoperative implant placement were selected in each mandible. The datasets from both CT systems were matched using a three-dimensional (3D) registration algorithm. The mean voxel gray values of the region around the implant sites were compared between MSCT and CBCT. Significant differences between the mean gray values obtained by CBCT and HU by MSCT were found. In all the selected ROIs, CBCT showed higher mean values than MSCT. A strong correlation (R=0.968) between mean voxel gray values of CBCT and mean HU of MSCT was determined. Voxel gray values from CBCT deviate from actual HU units. However, a strong linear correlation exists, which may permit deriving actual HU units from CBCT using linear regression models.

Renal vein thrombosis mimicking urinary calculus: a dilemma of diagnosis.

PubMed

Wang, Yimin; Chen, Shanwen; Wang, Wei; Liu, Jianyong; Jin, Baiye

2015-07-02

Renal vein thrombosis (RVT) with flank pain, and hematuria, is often mistaken with renal colic originating from ureteric or renal calculus. Especially in young and otherwise healthy patients, clinicians are easily misled by clinical presentation and calcified RVT. A 38-year-old woman presented with flank pain and hematuria suggestive of renal calculus on ultrasound. She underwent extracorporeal shock wave lithotripsy that failed, leading to the recommendation that percutaneous lithotomy was necessary to remove the renal calculus. In preoperative view of the unusual shape of the calculus without hydronephrosis, noncontrast computed tomography was taken and demonstrated left ureteric calculus. However computed tomography angiography revealed, to our surprise, a calcified RVT that was initially thought to be a urinary calculus. This case shows that a calcified RVT might mimic a urinary calculus on conventional ultrasonography and ureteric calculus on noncontrast computed tomography. Subsequent computed tomography angiography disclosed that a calcified RVT caused the imaging findings, thus creating a potentially dangerous clinical pitfall. Hence, it is suggested that the possibility of a RVT needs to be considered in the differential diagnosis whenever one detects an uncommon shape for a urinary calculus.

Inflammatory Pseudotumor-Like Follicular Dendritic Cell Sarcoma of the Spleen: Computed Tomography Imaging Characteristics in 5 Patients.

PubMed

Li, Xiumei; Shi, Zhenshan; You, Ruixiong; Li, Yueming; Cao, Dairong; Lin, Renjie; Huang, Xinming

The purpose of this study was to retrospectively review the computed tomography (CT) and clinicopathological characteristics of inflammatory pseudotumor (IPT)-like follicular dendritic cell sarcoma (FDCS) of the spleen in 5 patients. Clinical, pathologic, and CT imaging findings of 5 patients with IPT-like FDCS of the spleen were reviewed and analyzed. Computed tomography imaging and pathologic features were compared. Abdominal unenhanced CT revealed a well-defined hypodense mass in the spleen with complex internal architecture with focal necrosis and/or speckle-strip calcification. On postcontrast CT, slightly delayed enhancement was observed in 5 cases. Four patients had a normalized spleen. The fourth patient had lung metastasis. The fifth patient had 2 relatively small lesions as well as metastases to the spine. Computed tomography imaging features of IPT-like FDCS of the spleen are distinctly different from other hypovascular splenic neoplasm; however, the definitive diagnosis requires further confirmation with needle biopsy or surgery. Inflammatory pseudotumor-like FDCS of the spleen should be suggested by using the CT imaging features of the splenic mass with evidence of metastatic disease.

Malignant head and neck tumours in Radiology Department JPMC Karachi -- a tertiary care experience.

PubMed

Kadri, Shazia; Uddin, Sami; Ahmed, Naveed; Mahmood, Tariq

2015-08-01

To study age, gender and sites of malignant head and neck tumours on contrast-enhanced computed tomography and to elucidate its role. The retrospective study was conducted at the Jinnah Postgraduate Medical Centre, Karachi, and comprised data of patients with histologically proven malignant head and neck tumours reporting from February 2013 to February 2014. Contrast enhanced computed tomography with puffed cheek technique was done in cases of oral cancer, while routine contrast computed tomography was done in cases of other head and neck tumours. SPSS 19 was used for statistical analysis. A total of 100 biopsy-proven cases of malignant tumours comprised the study sample. The male: female ratio was 1.5:1 with an overall mean age of 46.4±16-76 years. . The most common histopathologically proven tumour was squamous cell carcinoma affecting oral mucosa 43(43%), followed by larynx 27(27%) and pharynx 10(10%) . Oral squamous cell carcinoma was the commonest tumour. Compute tomography scan with puffed cheek technique played a beneficial role in locating the site of primary tumour.

Imaging of the midpalatal suture in a porcine model: flat-panel volume computed tomography compared with multislice computed tomography.

PubMed

Hahn, Wolfram; Fricke-Zech, Susanne; Fialka-Fricke, Julia; Dullin, Christian; Zapf, Antonia; Gruber, Rudolf; Sennhenn-kirchner, Sabine; Kubein-Meesenburg, Dietmar; Sadat-Khonsari, Reza

2009-09-01

An investigation was conducted to compare the image quality of prototype flat-panel volume computed tomography (fpVCT) and multislice computed tomography (MSCT) of suture structures. Bone samples were taken from the midpalatal suture of 5 young (16 weeks) and 5 old (200 weeks) Sus scrofa domestica and fixed in formalin solution. An fpVCT prototype and an MSCT were used to obtain images of the specimens. The facial reformations were assessed by 4 observers using a 1 (excellent) to 5 (poor) rating scale for the weighted criteria visualization of the suture structure. A linear mixed model was used for statistical analysis. Results with P < .05 were considered to be statistically significant. The visualization of the suture of young specimens was significantly better than that of older animals (P < .001). The visualization of the suture with fpVCT was significantly better than that with MSCT (P < .001). Compared with MSCT, fpVCT produces superior results in the visualization of the midpalatal suture in a Sus scrofa domestica model.

Spectrally resolving and scattering-compensated x-ray luminescence/fluorescence computed tomography

PubMed Central

Cong, Wenxiang; Shen, Haiou; Wang, Ge

2011-01-01

The nanophosphors, or other similar materials, emit near-infrared (NIR) light upon x-ray excitation. They were designed as optical probes for in vivo visualization and analysis of molecular and cellular targets, pathways, and responses. Based on the previous work on x-ray fluorescence computed tomography (XFCT) and x-ray luminescence computed tomography (XLCT), here we propose a spectrally-resolving and scattering-compensated x-ray luminescence/fluorescence computed tomography (SXLCT or SXFCT) approach to quantify a spatial distribution of nanophosphors (other similar materials or chemical elements) within a biological object. In this paper, the x-ray scattering is taken into account in the reconstruction algorithm. The NIR scattering is described in the diffusion approximation model. Then, x-ray excitations are applied with different spectra, and NIR signals are measured in a spectrally resolving fashion. Finally, a linear relationship is established between the nanophosphor distribution and measured NIR data using the finite element method and inverted using the compressive sensing technique. The numerical simulation results demonstrate the feasibility and merits of the proposed approach. PMID:21721815

Radiolabeling, whole-body single photon emission computed tomography/computed tomography imaging, and pharmacokinetics of carbon nanohorns in mice

PubMed Central

Zhang, Minfang; Jasim, Dhifaf A; Ménard-Moyon, Cécilia; Nunes, Antonio; Iijima, Sumio; Bianco, Alberto; Yudasaka, Masako; Kostarelos, Kostas

2016-01-01

In this work, we report that the biodistribution and excretion of carbon nanohorns (CNHs) in mice are dependent on their size and functionalization. Small-sized CNHs (30–50 nm; S-CNHs) and large-sized CNHs (80–100 nm; L-CNHs) were chemically functionalized and radiolabeled with [111In]-diethylenetriaminepentaacetic acid and intravenously injected into mice. Their tissue distribution profiles at different time points were determined by single photon emission computed tomography/computed tomography. The results showed that the S-CNHs circulated longer in blood, while the L-CNHs accumulated faster in major organs like the liver and spleen. Small amounts of S-CNHs- and L-CNHs were excreted in urine within the first few hours postinjection, followed by excretion of smaller quantities within the next 48 hours in both urine and feces. The kinetics of excretion for S-CNHs were more rapid than for L-CNHs. Both S-CNH and L-CNH material accumulated mainly in the liver and spleen; however, S-CNH accumulation in the spleen was more prominent than in the liver. PMID:27524892

Clinical and Radiographic Response of Extramedullary Leukemia in Patients Treated With Gemtuzumab Ozogamicin.

PubMed

McNeil, Michael J; Parisi, Marguerite T; Hijiya, Nobuko; Meshinchi, Soheil; Cooper, Todd; Tarlock, Katherine

2018-05-04

Extramedullary leukemia (EML) is common in pediatric acute leukemia and can present at diagnosis or relapse. CD33 is detected on the surface of myeloid blasts in many patients with acute myelogenous leukemia and is the target of the antibody drug conjugate gemtuzumab ozogamicin (GO). Here we present 2 patients with CD33 EML treated with GO. They achieved significant response, with reduction of EML on both clinical and radiographic exams, specifically fluorine fluorodeoxyglucose positron emission tomography/computed tomography, demonstrating potential for targeted therapy with GO as a means of treating EML in patients with CD33 leukemia and the utility of fluorine fluorodeoxyglucose positron emission tomography/computed tomography monitoring in EML.

68Gallium-Arginine-Glycine-Aspartic Acid and 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Chondroblastic Osteosarcoma of the Skull.

PubMed

Orunmuyi, Akintunde; Modiselle, Moshe; Lengana, Thabo; Ebenhan, Thomas; Vorster, Mariza; Sathekge, Mike

2017-09-01

We report the case of a 32 year-old male with Chondroblastic Osteosarcoma of the skull, which was imaged with both 18 [F]fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) and 68 Gallium-arginine-glycine-aspartic acid ( 68 Ga-RGD) PET/CT. The 18 F-FDG PET/CT did not demonstrate the tumour, whereas the 68 Ga-RGD PET/CT clearly depicted a left-sided frontal tumour. 68 Ga-RGD PET/CT may be a clinically useful imaging modality for early detection of recurrent osteosarcoma, considering the limitations of 18 F-FDG PET in a setting of low glycolytic activity.

Nonmetastatic Castration-resistant Prostate Cancer: A Modern Perspective.

PubMed

Cancian, Madeline; Renzulli, Joseph F

2018-06-01

Nonmetastatic castration-resistant prostate cancer (nmCRPC) presents a challenge to urologists as currently there are no Food and Drug Administration-approved therapies. However, there are new imaging modalities, including fluciclovine positron emission tomography-computed tomography and Ga-PSMA (prostate specific membrane antigent) positron emission tomography-computed tomography, which are improving accuracy of diagnosis. With improved imaging, we are better able to target therapy. Today there are 3 ongoing clinical trials studying second-generation antiandrogens in nmCRPC, which hold the promise of a new treatment paradigm. In this article, we will review the new imaging techniques and the rationale behind novel treatment modalities in nmCRPC. Copyright © 2018 Elsevier Inc. All rights reserved.

Optimization of a Solid-State Electron Spin Qubit Using Gate Set Tomography (Open Access, Publisher’s Version)

DTIC Science & Technology

2016-10-13

enielse@sandia.gov and a.morello@unsw.edu.au Keywords: quantum computing , silicon, tomography Supplementarymaterial for this article is available online...Abstract State of the art qubit systems are reaching the gatefidelities required for scalable quantum computation architectures. Further improvements in...and addressedwhen the qubit is usedwithin a fault-tolerant quantum computation scheme. 1. Introduction One of themain challenges in the physical

Adaptive-optics optical coherence tomography processing using a graphics processing unit.

PubMed

Shafer, Brandon A; Kriske, Jeffery E; Kocaoglu, Omer P; Turner, Timothy L; Liu, Zhuolin; Lee, John Jaehwan; Miller, Donald T

2014-01-01

Graphics processing units are increasingly being used for scientific computing for their powerful parallel processing abilities, and moderate price compared to super computers and computing grids. In this paper we have used a general purpose graphics processing unit to process adaptive-optics optical coherence tomography (AOOCT) images in real time. Increasing the processing speed of AOOCT is an essential step in moving the super high resolution technology closer to clinical viability.

High-Resolution Computed Tomography and Pulmonary Function Findings of Occupational Arsenic Exposure in Workers.

PubMed

Ergün, Recai; Evcik, Ender; Ergün, Dilek; Ergan, Begüm; Özkan, Esin; Gündüz, Özge

2017-05-05

The number of studies where non-malignant pulmonary diseases are evaluated after occupational arsenic exposure is very few. To investigate the effects of occupational arsenic exposure on the lung by high-resolution computed tomography and pulmonary function tests. Retrospective cross-sectional study. In this study, 256 workers with suspected respiratory occupational arsenic exposure were included, with an average age of 32.9±7.8 years and an average of 3.5±2.7 working years. Hair and urinary arsenic levels were analysed. High-resolution computed tomography and pulmonary function tests were done. In workers with occupational arsenic exposure, high-resolution computed tomography showed 18.8% pulmonary involvement. In pulmonary involvement, pulmonary nodule was the most frequently seen lesion (64.5%). The other findings of pulmonary involvement were 18.8% diffuse interstitial lung disease, 12.5% bronchiectasis, and 27.1% bullae-emphysema. The mean age of patients with pulmonary involvement was higher and as they smoked more. The pulmonary involvement was 5.2 times higher in patients with skin lesions because of arsenic. Diffusing capacity of lung for carbon monoxide was significantly lower in patients with pulmonary involvement. Besides lung cancer, chronic occupational inhalation of arsenic exposure may cause non-malignant pulmonary findings such as bronchiectasis, pulmonary nodules and diffuse interstitial lung disease. So, in order to detect pulmonary involvement in the early stages, workers who experience occupational arsenic exposure should be followed by diffusion test and high-resolution computed tomography.

The Influence of Reconstruction Kernel on Bone Mineral and Strength Estimates Using Quantitative Computed Tomography and Finite Element Analysis.

PubMed

Michalski, Andrew S; Edwards, W Brent; Boyd, Steven K

2017-10-17

Quantitative computed tomography has been posed as an alternative imaging modality to investigate osteoporosis. We examined the influence of computed tomography convolution back-projection reconstruction kernels on the analysis of bone quantity and estimated mechanical properties in the proximal femur. Eighteen computed tomography scans of the proximal femur were reconstructed using both a standard smoothing reconstruction kernel and a bone-sharpening reconstruction kernel. Following phantom-based density calibration, we calculated typical bone quantity outcomes of integral volumetric bone mineral density, bone volume, and bone mineral content. Additionally, we performed finite element analysis in a standard sideways fall on the hip loading configuration. Significant differences for all outcome measures, except integral bone volume, were observed between the 2 reconstruction kernels. Volumetric bone mineral density measured using images reconstructed by the standard kernel was significantly lower (6.7%, p < 0.001) when compared with images reconstructed using the bone-sharpening kernel. Furthermore, the whole-bone stiffness and the failure load measured in images reconstructed by the standard kernel were significantly lower (16.5%, p < 0.001, and 18.2%, p < 0.001, respectively) when compared with the image reconstructed by the bone-sharpening kernel. These data suggest that for future quantitative computed tomography studies, a standardized reconstruction kernel will maximize reproducibility, independent of the use of a quantitative calibration phantom. Copyright © 2017 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

Assessment of cardiovascular risk profile based on measurement of tophus volume in patients with gout.

PubMed

Lee, Kyung-Ann; Ryu, Se-Ri; Park, Seong-Jun; Kim, Hae-Rim; Lee, Sang-Heon

2018-05-01

Hyperuricemia and gout are associated with increased risk of cardiovascular disease and metabolic syndrome. The aim of this study was to evaluate the correlation of total tophus volumes, measured using dual-energy computed tomography, with cardiovascular risk and the presence of metabolic syndrome. Dual-energy computed tomography datasets from 91 patients with a diagnosis of gout were analyzed retrospectively. Patients who received urate lowering therapy were excluded to avoid the effect on tophus volume. The total volumes of tophaceous deposition were quantified using automated volume assessment software. The 10-year cardiovascular risk using the Framingham Risk Score and metabolic syndrome based on the Third Adult Treatment Panel criteria were estimated. Fifty-five and 36 patients with positive and negative dual-energy computed tomography results, respectively, were assessed. Patients with positive dual-energy computed tomography results showed significantly higher systolic blood pressure, diastolic blood pressure, fasting glucose, and higher prevalence of chronic kidney disease, compared with those with negative dual-energy computed tomography results. The total tophus volumes were significantly correlated with the Framingham Risk Score, and the number of metabolic syndrome components (r = 0.22 and p = 0.036 and r = 0.373 and p < 0.001, respectively). The total tophus volume was one of the independent prognostic factors for the Framingham Risk Score in a multivariate analysis. This study showed the correlation of total tophus volumes with cardiovascular risk and metabolic syndrome-related comorbidities. A high urate burden could affect unfavorable cardiovascular profiles.

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

Thrombus aspiration catheter is a Dottering balloon.

PubMed

Sheshagiri Rao, D; Barik, Ramachandra; Prasad, Akula Siva

2016-01-01

Coronary angiogram in a young man with history of STEMI with delayed presentation revealed subtotal occlusion of left anterior descending artery (LAD) with large thrombotic filling defect distal to the critical lesion. PCI was preferred without delay because of ongoing chest pain. Several runs of thrombus aspiration failed to detect any visible thrombus. However, the immediate angiogram after thrombus aspiration showed complete distal embolization of the thrombus which could have been achieved by Dottering or balloon dilatation. In contrary to the general perception, does thrombus aspiration push more thrombus than it can aspirate? Copyright © 2016 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Single photon emission computed tomography and oth selected computer topics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frey, G.D.

1981-07-01

This book, the proceedings of a meeting in January 1980, contains 21 papers. Thirteen are devoted to aspects of emission tomography, four to nuclear cardiology, and five to other topics. The initial set of papers consists of reviews of the single photon emission tomography process. These include transverse axial tomography using scintillation cameras and other devices, longitudinal section tomography, and pin-hole and slant-hole systems. These reviews are generally well done, but as might be expected, lack any coherence from paper to paper. The papers on nuclear cardiology include several of Fourier analysis in nuclear cardiology and one on shunt quantification.more » Other clinical papers are on quantifying Tc-99m glucoheptonate uptake in the brain and on iron-59 retention studies. A general criticism of the book is the poor quality of photographic reproductions.« less

Automatic vasculature identification in coronary angiograms by adaptive geometrical tracking.

PubMed

Xiao, Ruoxiu; Yang, Jian; Goyal, Mahima; Liu, Yue; Wang, Yongtian

2013-01-01

As the uneven distribution of contrast agents and the perspective projection principle of X-ray, the vasculatures in angiographic image are with low contrast and are generally superposed with other organic tissues; therefore, it is very difficult to identify the vasculature and quantitatively estimate the blood flow directly from angiographic images. In this paper, we propose a fully automatic algorithm named adaptive geometrical vessel tracking (AGVT) for coronary artery identification in X-ray angiograms. Initially, the ridge enhancement (RE) image is obtained utilizing multiscale Hessian information. Then, automatic initialization procedures including seed points detection, and initial directions determination are performed on the RE image. The extracted ridge points can be adjusted to the geometrical centerline points adaptively through diameter estimation. Bifurcations are identified by discriminating connecting relationship of the tracked ridge points. Finally, all the tracked centerlines are merged and smoothed by classifying the connecting components on the vascular structures. Synthetic angiographic images and clinical angiograms are used to evaluate the performance of the proposed algorithm. The proposed algorithm is compared with other two vascular tracking techniques in terms of the efficiency and accuracy, which demonstrate successful applications of the proposed segmentation and extraction scheme in vasculature identification.

Potential risk of alpha-glucosidase inhibitor administration in prostate cancer external radiotherapy by exceptional rectal gas production: a case report.

PubMed

Nishimura, Takuya; Yamazaki, Hideya; Iwama, Kazuki; Oota, Yoshitaka; Aibe, Norihiro; Nakamura, Satoaki; Yoshida, Ken; Okabe, Haruumi; Yamada, Kei

2014-05-05

Radiotherapy is a standard treatment for prostate cancer, and image-guided radiotherapy is increasingly being used to aid precision of dose delivery to targeted tissues. However, precision during radiotherapy cannot be maintained when unexpected intrafraction organ motion occurs. We report our experience of internal organ motion caused by persistent gas production in a patient taking an alpha-glucosidase inhibitor. A 68-year-old Japanese man with prostate cancer visited our institution for treatment with helical tomotherapy. He suffered from diabetes mellitus and took an alpha-glucosidase inhibitor. Routine treatment planning computed tomography showed a large volume of rectal gas; an enema was given to void the rectum. Subsequent treatment planning computed tomography again showed a large volume of gas. After exercise (walking) to remove the intestinal gas, a third scan was performed as a test scan without tight fixation, which showed a sufficiently empty rectum for planning. However, after only a few minutes, treatment planning computed tomography again showed extreme accumulation of gas. Therefore, we postponed treatment planning computed tomography and consulted his doctor to suspend the alpha-glucosidase inhibitor, which was the expected cause of his persistent gas. Four days after the alpha-glucosidase inhibitor regimen was suspended, we took a fourth treatment planning computed tomography and made a treatment plan without gas accumulation. Thereafter, the absence of rectal gas accumulation was confirmed using daily megavolt computed tomography before treatment, and the patient received 37 fractions of intensity-modified radiotherapy at 74 Gy without rectal gas complications. In this case study, the alpha-glucosidase inhibitor induced the accumulation of intestinal gas, which may have caused unexpected organ motion, untoward reactions, and insufficient doses to clinical targets. We suggest that patients who are taking an alpha-glucosidase inhibitor for diabetes should discontinue use of that particular medicine prior to beginning radiotherapy.

Comparison of Online 6 Degree-of-Freedom Image Registration of Varian TrueBeam Cone-Beam CT and BrainLab ExacTrac X-Ray for Intracranial Radiosurgery.

PubMed

Li, Jun; Shi, Wenyin; Andrews, David; Werner-Wasik, Maria; Lu, Bo; Yu, Yan; Dicker, Adam; Liu, Haisong

2017-06-01

The study was aimed to compare online 6 degree-of-freedom image registrations of TrueBeam cone-beam computed tomography and BrainLab ExacTrac X-ray imaging systems for intracranial radiosurgery. Phantom and patient studies were performed on a Varian TrueBeam STx linear accelerator (version 2.5), which is integrated with a BrainLab ExacTrac imaging system (version 6.1.1). The phantom study was based on a Rando head phantom and was designed to evaluate isocenter location dependence of the image registrations. Ten isocenters at various locations representing clinical treatment sites were selected in the phantom. Cone-beam computed tomography and ExacTrac X-ray images were taken when the phantom was located at each isocenter. The patient study included 34 patients. Cone-beam computed tomography and ExacTrac X-ray images were taken at each patient's treatment position. The 6 degree-of-freedom image registrations were performed on cone-beam computed tomography and ExacTrac, and residual errors calculated from cone-beam computed tomography and ExacTrac were compared. In the phantom study, the average residual error differences (absolute values) between cone-beam computed tomography and ExacTrac image registrations were 0.17 ± 0.11 mm, 0.36 ± 0.20 mm, and 0.25 ± 0.11 mm in the vertical, longitudinal, and lateral directions, respectively. The average residual error differences in the rotation, roll, and pitch were 0.34° ± 0.08°, 0.13° ± 0.09°, and 0.12° ± 0.10°, respectively. In the patient study, the average residual error differences in the vertical, longitudinal, and lateral directions were 0.20 ± 0.16 mm, 0.30 ± 0.18 mm, 0.21 ± 0.18 mm, respectively. The average residual error differences in the rotation, roll, and pitch were 0.40°± 0.16°, 0.17° ± 0.13°, and 0.20° ± 0.14°, respectively. Overall, the average residual error differences were <0.4 mm in the translational directions and <0.5° in the rotational directions. ExacTrac X-ray image registration is comparable to TrueBeam cone-beam computed tomography image registration in intracranial treatments.

Spine Trabecular Bone Score as an Indicator of Bone Microarchitecture at the Peripheral Skeleton in Kidney Transplant Recipients.

PubMed

Luckman, Matthew; Hans, Didier; Cortez, Natalia; Nishiyama, Kyle K; Agarawal, Sanchita; Zhang, Chengchen; Nikkel, Lucas; Iyer, Sapna; Fusaro, Maria; Guo, Edward X; McMahon, Donald J; Shane, Elizabeth; Nickolas, Thomas L

2017-04-03

Studies using high-resolution peripheral quantitative computed tomography showed progressive abnormalities in cortical and trabecular microarchitecture and biomechanical competence over the first year after kidney transplantation. However, high-resolution peripheral computed tomography is a research tool lacking wide availability. In contrast, the trabecular bone score is a novel and widely available tool that uses gray-scale variograms of the spine image from dual-energy x-ray absorptiometry to assess trabecular quality. There are no studies assessing whether trabecular bone score characterizes bone quality in kidney transplant recipients. Between 2009 and 2010, we conducted a study to assess changes in peripheral skeletal microarchitecture, measured by high-resolution peripheral computed tomography, during the first year after transplantation in 47 patients managed with early corticosteroid-withdrawal immunosuppression. All adult first-time transplant candidates were eligible. Patients underwent imaging with high-resolution peripheral computed tomography and dual-energy x-ray absorptiometry pretransplantation and 3, 6, and 12 months post-transplantation. We now test if, during the first year after transplantation, trabecular bone score assesses the evolution of bone microarchitecture and biomechanical competence as determined by high-resolution peripheral computed tomography. At baseline and follow-up, among the 72% and 78%, respectively, of patients having normal bone mineral density by dual-energy x-ray absorptiometry, 53% and 50%, respectively, were classified by trabecular bone score as having high fracture risk. At baseline, trabecular bone score correlated with spine, hip, and ultradistal radius bone mineral density by dual-energy x-ray absorptiometry and cortical area, density, thickness, and porosity; trabecular density, thickness, separation, and heterogeneity; and stiffness and failure load by high-resolution peripheral computed tomography. Longitudinally, each percentage increase in trabecular bone score was associated with increases in trabecular number (0.35%±1.4%); decreases in trabecular thickness (-0.45%±0.15%), separation (-0.40%±0.15%), and network heterogeneity (-0.48%±0.20%); and increases in failure load (0.22%±0.09%) by high-resolution peripheral computed tomography (all P <0.05). Trabecular bone score may be a useful method to assess and monitor bone quality and strength and classify fracture risk in kidney transplant recipients. Copyright © 2017 by the American Society of Nephrology.

Spine Trabecular Bone Score as an Indicator of Bone Microarchitecture at the Peripheral Skeleton in Kidney Transplant Recipients

PubMed Central

Luckman, Matthew; Hans, Didier; Cortez, Natalia; Nishiyama, Kyle K.; Agarawal, Sanchita; Zhang, Chengchen; Nikkel, Lucas; Iyer, Sapna; Fusaro, Maria; Guo, Edward X.; McMahon, Donald J.; Shane, Elizabeth

2017-01-01

Background and objectives Studies using high-resolution peripheral quantitative computed tomography showed progressive abnormalities in cortical and trabecular microarchitecture and biomechanical competence over the first year after kidney transplantation. However, high-resolution peripheral computed tomography is a research tool lacking wide availability. In contrast, the trabecular bone score is a novel and widely available tool that uses gray-scale variograms of the spine image from dual-energy x-ray absorptiometry to assess trabecular quality. There are no studies assessing whether trabecular bone score characterizes bone quality in kidney transplant recipients. Design, settings, participants, & measurements Between 2009 and 2010, we conducted a study to assess changes in peripheral skeletal microarchitecture, measured by high-resolution peripheral computed tomography, during the first year after transplantation in 47 patients managed with early corticosteroid–withdrawal immunosuppression. All adult first-time transplant candidates were eligible. Patients underwent imaging with high-resolution peripheral computed tomography and dual-energy x-ray absorptiometry pretransplantation and 3, 6, and 12 months post-transplantation. We now test if, during the first year after transplantation, trabecular bone score assesses the evolution of bone microarchitecture and biomechanical competence as determined by high-resolution peripheral computed tomography. Results At baseline and follow-up, among the 72% and 78%, respectively, of patients having normal bone mineral density by dual-energy x-ray absorptiometry, 53% and 50%, respectively, were classified by trabecular bone score as having high fracture risk. At baseline, trabecular bone score correlated with spine, hip, and ultradistal radius bone mineral density by dual-energy x-ray absorptiometry and cortical area, density, thickness, and porosity; trabecular density, thickness, separation, and heterogeneity; and stiffness and failure load by high-resolution peripheral computed tomography. Longitudinally, each percentage increase in trabecular bone score was associated with increases in trabecular number (0.35%±1.4%); decreases in trabecular thickness (−0.45%±0.15%), separation (−0.40%±0.15%), and network heterogeneity (−0.48%±0.20%); and increases in failure load (0.22%±0.09%) by high-resolution peripheral computed tomography (all P<0.05). Conclusions Trabecular bone score may be a useful method to assess and monitor bone quality and strength and classify fracture risk in kidney transplant recipients. PMID:28348031

X-ray Micro-Tomography of Ablative Heat Shield Materials

NASA Technical Reports Server (NTRS)

Panerai, Francesco; Ferguson, Joseph; Borner, Arnaud; Mansour, Nagi N.; Barnard, Harold S.; MacDowell, Alastair A.; Parkinson, Dilworth Y.

2016-01-01

X-ray micro-tomography is a non-destructive characterization technique that allows imaging of materials structures with voxel sizes in the micrometer range. This level of resolution makes the technique very attractive for imaging porous ablators used in hypersonic entry systems. Besides providing a high fidelity description of the material architecture, micro-tomography enables computations of bulk material properties and simulations of micro-scale phenomena. This presentation provides an overview of a collaborative effort between NASA Ames Research Center and Lawrence Berkeley National Laboratory, aimed at developing micro-tomography experiments and simulations for porous ablative materials. Measurements are carried using x-rays from the Advanced Light Source at Berkeley Lab on different classes of ablative materials used in NASA entry systems. Challenges, strengths and limitations of the technique for imaging materials such as lightweight carbon-phenolic systems and woven textiles are discussed. Computational tools developed to perform numerical simulations based on micro-tomography are described. These enable computations of material properties such as permeability, thermal and radiative conductivity, tortuosity and other parameters that are used in ablator response models. Finally, we present the design of environmental cells that enable imaging materials under simulated operational conditions, such as high temperature, mechanical loads and oxidizing atmospheres.Keywords: Micro-tomography, Porous media, Ablation

Mesenteric angiography

MedlinePlus

... Arteriogram - abdomen; Mesenteric angiogram Images Mesenteric arteriography References Kaufman JA. Fundamentals of angiography. In: Kaufman JA, Lee MJ, eds. Vascular and Interventional Radiology: ...

Abernethy malformation with portal vein aneurysm in a child

PubMed Central

Chandrashekhara, Sheragaru H.; Bhalla, Ashu Seith; Gupta, Arun Kumar; Vikash, C. S.; Kabra, Susheel Kumar

2011-01-01

Abernethy malformation is an extremely rare anomaly of the splanchnic venous system. We describe multidetector computed tomography findings of an incidentally detected Abernethy malformation with portal vein aneurysm in a two-and-half-year old child. The computed tomography scan was performed for the evaluation of respiratory distress, poor growth, and loss of appetite. PMID:21430844

Transmission of Hepatitis C Virus during Computed Tomography Scanning with Contrast

PubMed Central

Rius, Cristina; Caylà, Joan A.

2008-01-01

Six cases of acute hepatitis C related to computed tomography scanning with contrast were identified in 3 hospitals. A patient with chronic hepatitis C had been subjected to the same procedure immediately before each patient who developed acute infection. Viral molecular analysis showed identity between isolates from cases with acute and chronic hepatitis C. PMID:18258135

An Integrated Teaching Method of Gross Anatomy and Computed Tomography Radiology

ERIC Educational Resources Information Center

Murakami, Tohru; Tajika, Yuki; Ueno, Hitoshi; Awata, Sachiko; Hirasawa, Satoshi; Sugimoto, Maki; Kominato, Yoshihiko; Tsushima, Yoshito; Endo, Keigo; Yorifuji, Hiroshi

2014-01-01

It is essential for medical students to learn and comprehend human anatomy in three dimensions (3D). With this in mind, a new system was designed in order to integrate anatomical dissections with diagnostic computed tomography (CT) radiology. Cadavers were scanned by CT scanners, and students then consulted the postmortem CT images during cadaver…

Computed tomography findings of gaseous necrosis in epithelial ovarian cancer: a report of three cases.

PubMed

Cronin, Paul; Crosse, Barbara; Lane, Geoff; Spencer, John A

2002-01-01

Necrosis in pathologic specimens of ovarian cancer is well documented; however, computed tomography (CT) evidence of gaseous necrosis in the absence of fistulation with bowel has not yet been described. We report three cases of ovarian adenocarcinoma that on CT showed evidence of gross gaseous necrosis, mimicking a pelvic abscess.

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance

Science.gov Websites

Finding Aids dropdown arrow Site Map A-Z Index Menu Synopsis Non-medical Uses of Computed Tomography (CT materials characterizations, and to provide non-destructive evaluations for discovering flaws in parts presence and facilitate the recovery/extraction of oil, water, coal, and/or gas; and to provide non

Utilization of high resolution computed tomography to visualize the three dimensional structure and function of plant vasculature

USDA-ARS?s Scientific Manuscript database

High resolution x-ray computed tomography (HRCT) is a non-destructive diagnostic imaging technique with sub-micron resolution capability that is now being used to evaluate the structure and function of plant xylem network in three dimensions (3D). HRCT imaging is based on the same principles as medi...

Tangential scanning of hardwood logs: developing an industrial computer tomography scanner

Treesearch

Nand K. Gupta; Daniel L. Schmoldt; Bruce Isaacson

1999-01-01

It is generally believed that noninvasive scanning of hardwood logs such as computer tomography (CT) scanning prior to initial breakdown will greatly improve the processing of logs into lumber. This belief, however, has not translated into rapid development and widespread installation of industrial CT scanners for log processing. The roadblock has been more operational...

An Easily Assembled Laboratory Exercise in Computed Tomography

ERIC Educational Resources Information Center

Mylott, Elliot; Klepetka, Ryan; Dunlap, Justin C.; Widenhorn, Ralf

2011-01-01

In this paper, we present a laboratory activity in computed tomography (CT) primarily composed of a photogate and a rotary motion sensor that can be assembled quickly and partially automates data collection and analysis. We use an enclosure made with a light filter that is largely opaque in the visible spectrum but mostly transparent to the near…

Documentation of the ISA Micro Computed Tomography System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, William D.; Smith, Jerel A.

2013-12-18

This document is intended to provide information on the ISA Micro Computed Tomography (MicroCT) system that will be installed in Yavne, Israel. X-ray source, detector, and motion control hardware are specified as well as specimen platforms, containers, and reference material types. Most of the details on the system are derived from Reference 1 and 2.

The Role of High-resolution Peripheral Quantitative Computed Tomography as a Biomarker for Joint Damage in Inflammatory Arthritis.

PubMed

Tam, Lai-Shan

2016-10-01

Since 2011, members of the SPECTRA Collaboration (Study grouP for xtrEme-Computed Tomography in Rheumatoid Arthritis) have investigated the validity, reliability, and responsiveness of high-resolution peripheral quantitative computed tomography (HR-pQCT) as a biomarker for joint damage in inflammatory arthritis. Presented in this series of articles are a systematic review of HR-pQCT-related findings to date, a review of selected images of cortical and subchondral trabecular bone of metacarpophalangeal (MCP) joints, results of a consensus process to standardize the definition of erosions and their quantification, as well as an examination of the effect of joint flexion on width and volume assessment of the joint space.

Electron tomography and computer visualisation of a three-dimensional 'photonic' crystal in a butterfly wing-scale.

PubMed

Argyros, A; Manos, S; Large, M C J; McKenzie, D R; Cox, G C; Dwarte, D M

2002-01-01

A combination of transmission electron tomography and computer modelling has been used to determine the three-dimensional structure of the photonic crystals found in the wing-scales of the Kaiser-I-Hind butterfly (Teinopalpus imperialis). These scales presented challenges for electron microscopy because the periodicity of the structure was comparable to the thickness of a section and because of the complex connectivity of the object. The structure obtained has been confirmed by taking slices of the three-dimensional computer model constructed from the tomography and comparing these with transmission electron microscope (TEM) images of microtomed sections of the actual scale. The crystal was found to have chiral tetrahedral repeating units packed in a triclinic lattice.

Dysphagia lusorium in elderly: A case report

PubMed Central

Kantarceken, Bulent; Bulbuloglu, Ertan; Yuksel, Murvet; Cetinkaya, Ali

2004-01-01

AIM: Late unset of dysphagia due to vascular abnormalities is a rare condition. We aimed to present a case of right subclavian artery abnormalities caused dysphagia in the elderly. METHODS: A 68-year-old female was admitted with dysphagia seven months ago. Upper endoscopic procedures and routine examinations could not demonstrate any etiology. Multislice computed thorax tomography was performed for probable extra- esophagial lesions. RESULTS: Multislice computed thorax tomography showed right subclavian artery abnormality and esophagial compression with this aberrant artery. CONCLUSION: Causes of dysphagia in the elderly are commonly malignancies, strictures and/or motility disorders. If routine examinations and endoscopic procedures fail to show any etiology, rare vascular abnormalities can be considered in such patients. Multislice computed tomography is a usefull choice in such conditions. PMID:15285045

Finance for practicing radiologists.

PubMed

Berlin, Jonathan W; Lexa, Frank James

2005-03-01

This article reviews basic finance for radiologists. Using the example of a hypothetical outpatient computed tomography center, readers are introduced to the concept of net present value. This concept refers to the current real value of anticipated income in the future, realizing that revenue in the future has less value than it does today. Positive net present value projects add wealth to a practice and should be pursued. The article details how costs and revenues for a hypothetical outpatient computed tomography center are determined and elucidates the difference between fixed costs and variable costs. The article provides readers with the steps used to calculate the break-even volume for an outpatient computed tomography center given situation-specific assumptions regarding staff, equipment lease rates, rent, and third-party payer mix.

Contrast‐enhanced computed tomography with myocardial three‐dimensional printing can guide treatment in symptomatic hypertrophic obstructive cardiomyopathy

PubMed Central

Hamatani, Yasuhiro; Amaki, Makoto; Kanzaki, Hideaki; Yamashita, Kizuku; Nakashima, Yasuteru; Shibata, Atsushi; Okada, Atsushi; Takahama, Hiroyuki; Hasegawa, Takuya; Shimahara, Yusuke; Sugano, Yasuo; Fujita, Tomoyuki; Shiraishi, Isao; Yasuda, Satoshi; Kobayashi, Junjiro

2017-01-01

Abstract Both surgical myectomy and percutaneous transluminal septal myocardial ablation are effective treatments for drug‐refractory symptomatic hypertrophic obstructive cardiomyopathy (HOCM). However, in some cases, it is not easy to elucidate the abnormal structure of left ventricular outflow obstruction to adopt these treatments. Here, we presented a young female patient with drug‐refractory symptomatic HOCM. In this case, contrast‐enhanced computed tomography enabled us to assess the suitability of percutaneous transluminal septal myocardial ablation. By creating three‐dimensional printed models using computed tomography data, we could also visualize intracardiac structure and simulate the surgical procedure. A multimodality assessment strategy is useful for evaluating patients complicated with drug‐refractory symptomatic HOCM. PMID:29154429

Patients who reattend after head injury: a high risk group.

PubMed Central

Voss, M.; Knottenbelt, J. D.; Peden, M. M.

1995-01-01

OBJECTIVE--To assess risk factors for important neurosurgical effects in patients who reattend after head injury. DESIGN--Retrospective study. SUBJECTS--606 patients who reattended a trauma unit after minor head injury. MAIN OUTCOME MEASURES--Intracranial abnormality detected on computed tomography or the need for neurosurgical intervention. RESULTS--Five patients died: two from unrelated causes and three from raised intracranial pressure. On multiple regression analysis the only significant predictor for both abnormality on computed tomography (14.4% of reattenders) and the need for operation (5% of reattenders) was vault fracture seen on the skull radiograph (P < 10(-6)); predictors for abnormal computed tomogram were a Glasgow coma scale score < 15 at either first or second attendance (P < 0.0001) and convulsion at second attendance (P < 0.05); predictive for operation only was penetrating injury of the skull (P < 10(-6)). On contingency table analysis these associations were confirmed. In addition significant associations with both abnormality on computed tomography and operation were focal neurological abnormality, weakness, or speech disturbance. Amnesia or loss of consciousness at the time of initial injury, personality change, and seizures were significantly associated only with abnormality on computed tomography. Headache, dizziness, nausea, and vomiting were common in reattenders but were found to have no independent significance. CONCLUSIONS--All patients who reattend after head injury should undergo computed tomography as at least 14% of scans can be expected to yield positive results. Where this facility is not available patients with predictors for operation should be urgently referred for neurosurgical opinion. Other patients can be readmitted and need referral only if symptoms persist despite symptomatic treatment or there is neurological deterioration while under observation. These patients are a high risk group and should be treated seriously. PMID:8520273

Lung Hot Spot Without Corresponding Computed Tomography Abnormality on Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography: Artifactual or Real, Iatrogenic or Pathologic?

PubMed

Liu, Yiyan

Focal lung uptake without corresponding lesions or abnormalities on computed tomography (CT) scan poses a dilemma in the interpretation of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT). A limited number of case reports have previously suggested an artifactual or iatrogenic nature of the uptake. In the present study, 8 relevant cases were included within a retrospective search of the database. Medical records were reviewed for follow-up radiological and pathologic information. In 7 of 8 cases with focal increased FDG uptake but no corresponding lesions or abnormalities on CT scan, the lung hot spots were artifactual or iatrogenic upon follow-up diagnostic chest CT or repeated PET/CT or both the scans. Microemboli were most likely a potential cause of the pulmonary uptake, with or without partial paravenous injection. One case in the series had a real pulmonary lesion demonstrated on follow-up PET/CT scans and on surgical pathology, although the initial integrated CT and follow-up diagnostic chest CT scans revealed negative findings to demonstrate pulmonary abnormalities corresponding to the hot spot on the PET scan. In conclusion, the finding of a lung hot spot in the absence of anatomical abnormality on FDG PET/CT was most likely artifactual or iatrogenic, but it might also represent a real pulmonary lesion. Nonvisualization of anatomical abnormality could be because of its small size and position directly overlying a segmental vessel. Further image follow-up is necessary and important to clarify the nature of the uptake. Copyright © 2017 Elsevier Inc. All rights reserved.

Hybrid SPECT/CT imaging in neurology.

PubMed

Ciarmiello, Andrea; Giovannini, Elisabetta; Meniconi, Martina; Cuccurullo, Vincenzo; Gaeta, Maria Chiara

2014-01-01

In recent years, the SPECT/CT hybrid modality has led to a rapid development of imaging techniques in nuclear medicine, opening new perspectives for imaging staff and patients as well. However, while, the clinical role of positron emission tomography-computed tomography (PET-CT) is well consolidated, the diffusion and the consequent value of single-photon emission tomography-computed tomography (SPECT-CT) has yet to be weighed, Hence, there is a need for a careful analysis, comparing the "potential" benefits of the hybrid modality with the "established" ones of the standalone machine. The aim of this article is to analyze the impact of this hybrid tool on the diagnosis of diseases of the central nervous system, comparing strengths and weaknesses of both modalities through the use of SWOT analysis.

Stomach metastasis of breast carcinoma mimicking primary gastric neoplasm on fluorodeoxy glucose-positron emission tomography-computed tomography.

PubMed

Joshi, Prathamesh; Lele, Vikram; Jain, Reetu; Khubchandani, Shaila; Sinhasan, Shraddha

2013-04-01

We present fluorodeoxy glucose positron emission tomography-computed tomography (FDG-PET/CT) findings in a case of breast carcinoma. The PET/CT findings in this case were suspicious of second primary neoplasm in the stomach. However, on endoscopic biopsy, the lesion was found to be stomach metastasis of breast carcinoma with estrogen receptor positivity. Stomach is a rare site of breast carcinoma metastasis. Our case suggests that it is difficult to distinguish a stomach metastasis of breast cancer from a primary gastric cancer on the basis of clinical and imaging features. However, this differential diagnosis must be kept in mind and it is important to make such distinction because of its implications on patient management.

Performance dependence of hybrid x-ray computed tomography/fluorescence molecular tomography on the optical forward problem.

PubMed

Hyde, Damon; Schulz, Ralf; Brooks, Dana; Miller, Eric; Ntziachristos, Vasilis

2009-04-01

Hybrid imaging systems combining x-ray computed tomography (CT) and fluorescence tomography can improve fluorescence imaging performance by incorporating anatomical x-ray CT information into the optical inversion problem. While the use of image priors has been investigated in the past, little is known about the optimal use of forward photon propagation models in hybrid optical systems. In this paper, we explore the impact on reconstruction accuracy of the use of propagation models of varying complexity, specifically in the context of these hybrid imaging systems where significant structural information is known a priori. Our results demonstrate that the use of generically known parameters provides near optimal performance, even when parameter mismatch remains.

Ceramic and polymeric dental onlays evaluated by photo-elasticity, optical coherence tomography, and micro-computed tomography

NASA Astrophysics Data System (ADS)

Sinescu, Cosmin; Negrutiu, Meda; Topala, Florin; Ionita, Ciprian; Negru, Radu; Fabriky, Mihai; Marcauteanu, Corina; Bradu, Adrian; Dobre, George; Marsavina, Liviu; Rominu, Mihai; Podoleanu, Adrian

2011-10-01

Dental onlays are restorations used to repair rear teeth that have a mild to moderate amount of decay. They can also be used to restore teeth that are cracked or fractured if the damage is not severe enough to require a dental crown. The use of onlays requires less tooth reduction than does the use of metal fillings. This allows dentists to conserve more of a patient's natural tooth structure in the treatment process. The aims of this study are to evaluate the biomechanical comportment of the dental onlays, by using the 3D photo elasticity method and to investigate the integrity of the structures and their fitting to the dental support. For this optical coherence tomography and micro-computed tomography were employed. Both methods were used to investigate 37 dental onlays, 17 integral polymeric and 20 integral ceramic. The results permit to observe materials defects inside the ceramic or polymeric onlays situate in the biomechanically tensioned areas that could lead to fracture of the prosthetic structure. Marginal fitting problems of the onlays related to the teeth preparations were presented in order to observe the possibility of secondary cavities. The resulted images from the optical coherence tomography were verified by the micro-computed tomography. In conclusion, the optical coherence tomography can be used as a clinical method in order to evaluate the integrity of the dental ceramic and polymeric onlays and to investigate the quality of the marginal fitting to the teeth preparations.

Framework for cognitive analysis of dynamic perfusion computed tomography with visualization of large volumetric data

NASA Astrophysics Data System (ADS)

Hachaj, Tomasz; Ogiela, Marek R.

2012-10-01

The proposed framework for cognitive analysis of perfusion computed tomography images is a fusion of image processing, pattern recognition, and image analysis procedures. The output data of the algorithm consists of: regions of perfusion abnormalities, anatomy atlas description of brain tissues, measures of perfusion parameters, and prognosis for infracted tissues. That information is superimposed onto volumetric computed tomography data and displayed to radiologists. Our rendering algorithm enables rendering large volumes on off-the-shelf hardware. This portability of rendering solution is very important because our framework can be run without using expensive dedicated hardware. The other important factors are theoretically unlimited size of rendered volume and possibility of trading of image quality for rendering speed. Such rendered, high quality visualizations may be further used for intelligent brain perfusion abnormality identification, and computer aided-diagnosis of selected types of pathologies.

Computerized analysis of coronary artery disease: Performance evaluation of segmentation and tracking of coronary arteries in CT angiograms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Chuan, E-mail: chuan@umich.edu; Chan, Heang-Ping; Chughtai, Aamer

2014-08-15

Purpose: The authors are developing a computer-aided detection system to assist radiologists in analysis of coronary artery disease in coronary CT angiograms (cCTA). This study evaluated the accuracy of the authors’ coronary artery segmentation and tracking method which are the essential steps to define the search space for the detection of atherosclerotic plaques. Methods: The heart region in cCTA is segmented and the vascular structures are enhanced using the authors’ multiscale coronary artery response (MSCAR) method that performed 3D multiscale filtering and analysis of the eigenvalues of Hessian matrices. Starting from seed points at the origins of the left andmore » right coronary arteries, a 3D rolling balloon region growing (RBG) method that adapts to the local vessel size segmented and tracked each of the coronary arteries and identifies the branches along the tracked vessels. The branches are queued and subsequently tracked until the queue is exhausted. With Institutional Review Board approval, 62 cCTA were collected retrospectively from the authors’ patient files. Three experienced cardiothoracic radiologists manually tracked and marked center points of the coronary arteries as reference standard following the 17-segment model that includes clinically significant coronary arteries. Two radiologists visually examined the computer-segmented vessels and marked the mistakenly tracked veins and noisy structures as false positives (FPs). For the 62 cases, the radiologists marked a total of 10191 center points on 865 visible coronary artery segments. Results: The computer-segmented vessels overlapped with 83.6% (8520/10191) of the center points. Relative to the 865 radiologist-marked segments, the sensitivity reached 91.9% (795/865) if a true positive is defined as a computer-segmented vessel that overlapped with at least 10% of the reference center points marked on the segment. When the overlap threshold is increased to 50% and 100%, the sensitivities were 86.2% and 53.4%, respectively. For the 62 test cases, a total of 55 FPs were identified by radiologist in 23 of the cases. Conclusions: The authors’ MSCAR-RBG method achieved high sensitivity for coronary artery segmentation and tracking. Studies are underway to further improve the accuracy for the arterial segments affected by motion artifacts, severe calcified and noncalcified soft plaques, and to reduce the false tracking of the veins and other noisy structures. Methods are also being developed to detect coronary artery disease along the tracked vessels.« less

Pulmonary infection caused by Mycobacterium kansasii: findings on computed tomography of the chest*

PubMed Central

Mogami, Roberto; Goldenberg, Telma; de Marca, Patricia Gomes Cytrangulo; Mello, Fernanda Carvalho de Queiroz; Lopes, Agnaldo José

2016-01-01

Objective To describe the main tomography findings in patients diagnosed with pulmonary infection caused by Mycobacterium kansasii. Materials and Methods Retrospective study of computed tomography scans of 19 patients with pulmonary infection by M. kansasii. Results Of the 19 patients evaluated, 10 (52.6%) were male and 9 (47.4%) were female. The mean age of the patients was 58 years (range, 33-76 years). Computed tomography findings were as follows: architectural distortion, in 17 patients (89.5%); reticular opacities and bronchiectasis, in 16 (84.2%); cavities, in 14 (73.7%); centrilobular nodules, in 13 (68.4%); small consolidations, in 10 (52.6%); atelectasis and large consolidations, in 9 (47.4%); subpleural blebs and emphysema, in 6 (31.6%); and adenopathy, in 1 (5.3%). Conclusion There was a predominance of cavities, as well as of involvement of the small and large airways. The airway disease was characterized by bronchiectasis and bronchiolitis presenting as centrilobular nodules. PMID:27777472

Comparison of lens- and fiber-coupled CCD detectors for X-ray computed tomography

PubMed Central

Uesugi, K.; Hoshino, M.; Yagi, N.

2011-01-01

X-ray imaging detectors with an identical phosphor and a CCD chip but employing lens- and fiber-coupling between them have been compared. These are designed for X-ray imaging experiments, especially computed tomography, at the medium-length beamline at the SPring-8 synchrotron radiation facility. It was found that the transmittance of light to the CCD is about four times higher in the fiber-coupled detector. The uniformity of response in the lens-coupled detector has a global shading of up to 40%, while pixel-to-pixel variation owing to a chicken-wire pattern was dominant in the fiber-coupled detector. Apart from the higher transmittance, the fiber-coupled detector has a few characteristics that require attention when it is used for computed tomography, which are browning of the fiber, discontinuity in the image, image distortion, and dark spots in the chicken-wire pattern. Thus, it is most suitable for high-speed tomography of samples that tend to deform, for example biological and soft materials. PMID:21335908

A Smartphone Client-Server Teleradiology System for Primary Diagnosis of Acute Stroke

PubMed Central

2011-01-01

Background Recent advances in the treatment of acute ischemic stroke have made rapid acquisition, visualization, and interpretation of images a key factor for positive patient outcomes. We have developed a new teleradiology system based on a client-server architecture that enables rapid access to interactive advanced 2-D and 3-D visualization on a current generation smartphone device (Apple iPhone or iPod Touch, or an Android phone) without requiring patient image data to be stored on the device. Instead, a server loads and renders the patient images, then transmits a rendered frame to the remote device. Objective Our objective was to determine if a new smartphone client-server teleradiology system is capable of providing accuracies and interpretation times sufficient for diagnosis of acute stroke. Methods This was a retrospective study. We obtained 120 recent consecutive noncontrast computed tomography (NCCT) brain scans and 70 computed tomography angiogram (CTA) head scans from the Calgary Stroke Program database. Scans were read by two neuroradiologists, one on a medical diagnostic workstation and an iPod or iPhone (hereafter referred to as an iOS device) and the other only on an iOS device. NCCT brain scans were evaluated for early signs of infarction, which includes early parenchymal ischemic changes and dense vessel sign, and to exclude acute intraparenchymal hemorrhage and stroke mimics. CTA brain scans were evaluated for any intracranial vessel occlusion. The interpretations made on an iOS device were compared with those made at a workstation. The total interpretation times were recorded for both platforms. Interrater agreement was assessed. True positives, true negatives, false positives, and false negatives were obtained, and sensitivity, specificity, and accuracy of detecting the abnormalities on the iOS device were computed. Results The sensitivity, specificity, and accuracy of detecting intraparenchymal hemorrhage were 100% using the iOS device with a perfect interrater agreement (kappa = 1). The sensitivity, specificity, and accuracy of detecting acute parenchymal ischemic change were 94.1%, 100%, and 98.09% respectively for reader 1 and 97.05%, 100%, and 99.04% for reader 2 with nearly perfect interrater agreement (kappa = .8). The sensitivity, specificity, and accuracy of detecting dense vessel sign were 100%, 95.4%, and 96.19% respectively for reader 1 and 72.2%, 100%, and 95.23% for reader 2 using the iOS device with a good interrater agreement (kappa = .69). The sensitivity, specificity, and accuracy of detecting vessel occlusion on CT angiography scans were 94.4%, 100%, and 98.46% respectively for both readers using the iOS device, with perfect interrater agreement (kappa = 1). No significant difference (P < .05) was noted in the interpretation time between the workstation and iOS device. Conclusion The smartphone client-server teleradiology system appears promising and may have the potential to allow urgent management decisions in acute stroke. However, this study was retrospective, involved relatively few patient studies, and only two readers. Generalizing conclusions about its clinical utility, especially in other diagnostic use cases, should not be made until additional studies are performed. PMID:21550961

A smartphone client-server teleradiology system for primary diagnosis of acute stroke.

PubMed

Mitchell, J Ross; Sharma, Pranshu; Modi, Jayesh; Simpson, Mark; Thomas, Monroe; Hill, Michael D; Goyal, Mayank

2011-05-06

Recent advances in the treatment of acute ischemic stroke have made rapid acquisition, visualization, and interpretation of images a key factor for positive patient outcomes. We have developed a new teleradiology system based on a client-server architecture that enables rapid access to interactive advanced 2-D and 3-D visualization on a current generation smartphone device (Apple iPhone or iPod Touch, or an Android phone) without requiring patient image data to be stored on the device. Instead, a server loads and renders the patient images, then transmits a rendered frame to the remote device. Our objective was to determine if a new smartphone client-server teleradiology system is capable of providing accuracies and interpretation times sufficient for diagnosis of acute stroke. This was a retrospective study. We obtained 120 recent consecutive noncontrast computed tomography (NCCT) brain scans and 70 computed tomography angiogram (CTA) head scans from the Calgary Stroke Program database. Scans were read by two neuroradiologists, one on a medical diagnostic workstation and an iPod or iPhone (hereafter referred to as an iOS device) and the other only on an iOS device. NCCT brain scans were evaluated for early signs of infarction, which includes early parenchymal ischemic changes and dense vessel sign, and to exclude acute intraparenchymal hemorrhage and stroke mimics. CTA brain scans were evaluated for any intracranial vessel occlusion. The interpretations made on an iOS device were compared with those made at a workstation. The total interpretation times were recorded for both platforms. Interrater agreement was assessed. True positives, true negatives, false positives, and false negatives were obtained, and sensitivity, specificity, and accuracy of detecting the abnormalities on the iOS device were computed. The sensitivity, specificity, and accuracy of detecting intraparenchymal hemorrhage were 100% using the iOS device with a perfect interrater agreement (kappa=1). The sensitivity, specificity, and accuracy of detecting acute parenchymal ischemic change were 94.1%, 100%, and 98.09% respectively for reader 1 and 97.05%, 100%, and 99.04% for reader 2 with nearly perfect interrater agreement (kappa=.8). The sensitivity, specificity, and accuracy of detecting dense vessel sign were 100%, 95.4%, and 96.19% respectively for reader 1 and 72.2%, 100%, and 95.23% for reader 2 using the iOS device with a good interrater agreement (kappa=.69). The sensitivity, specificity, and accuracy of detecting vessel occlusion on CT angiography scans were 94.4%, 100%, and 98.46% respectively for both readers using the iOS device, with perfect interrater agreement (kappa=1). No significant difference (P<.05) was noted in the interpretation time between the workstation and iOS device. The smartphone client-server teleradiology system appears promising and may have the potential to allow urgent management decisions in acute stroke. However, this study was retrospective, involved relatively few patient studies, and only two readers. Generalizing conclusions about its clinical utility, especially in other diagnostic use cases, should not be made until additional studies are performed. ©J Ross Mitchell, Pranshu Sharma, Jayesh Modi, Mark Simpson, Monroe Thomas, Michael D. Hill, Mayank Goyal.

Emission Computed Tomography: A New Technique for the Quantitative Physiologic Study of Brain and Heart in Vivo

DOE R&D Accomplishments Database

Phelps, M. E.; Hoffman, E. J.; Huang, S. C.; Schelbert, H. R.; Kuhl, D. E.

1978-01-01

Emission computed tomography can provide a quantitative in vivo measurement of regional tissue radionuclide tracer concentrations. This facility when combined with physiologic models and radioactively labeled physiologic tracers that behave in a predictable manner allow measurement of a wide variety of physiologic variables. This integrated technique has been referred to as Physiologic Tomography (PT). PT requires labeled compounds which trace physiologic processes in a known and predictable manner, and physiologic models which are appropriately formulated and validated to derive physiologic variables from ECT data. In order to effectively achieve this goal, PT requires an ECT system that is capable of performing truly quantitative or analytical measurements of tissue tracer concentrations and which has been well characterized in terms of spatial resolution, sensitivity and signal to noise ratios in the tomographic image. This paper illustrates the capabilities of emission computed tomography and provides examples of physiologic tomography for the regional measurement of cerebral and myocardial metabolic rate for glucose, regional measurement of cerebral blood volume, gated cardiac blood pools and capillary perfusion in brain and heart. Studies on patients with stroke and myocardial ischemia are also presented.

Waste inspection tomography (WIT)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernardi, R.T.

1996-12-31

WIT is a self-sufficient mobile semitrailer for nondestructive evaluation and nondestructive assay of nuclear waste drums using x-ray and gamma-ray tomography. The recently completed Phase I included the design, fabrication, and initial testing of all WIT subsystems installed on-board the trailer. Initial test results include 2 MeV digital radiography, computed tomography, Anger camera imaging, single photon emission computed tomography, gamma-ray spectroscopy, collimated gamma scanning, and active and passive computed tomography using a 1.4 mCi source of {sup 166}Ho. These techniques were initially demonstrated on a 55-gallon phantom drum with 3 simulated waste matrices of combustibles, heterogeneous metals, and cement usingmore » check sources of gamma active isotopes such as {sup 137}Cs and {sup 133}Ba with 9-250 {mu}Ci activities. Waste matrix identification, isotopic identification, and attenuation-corrected gamma activity determination were demonstrated nondestructively and noninvasively in Phase I. Currently ongoing Phase II involves DOE site field test demonstrations at LLNL, RFETS, and INEL with real nuclear waste drums. Current WIT experience includes 55 gallon drums of cement, graphite, sludge, glass, metals, and combustibles. Thus far WIT has inspected drums with 0-20 gms of {sup 239}Pu.« less

Six-dimensional real and reciprocal space small-angle X-ray scattering tomography

NASA Astrophysics Data System (ADS)

Schaff, Florian; Bech, Martin; Zaslansky, Paul; Jud, Christoph; Liebi, Marianne; Guizar-Sicairos, Manuel; Pfeiffer, Franz

2015-11-01

When used in combination with raster scanning, small-angle X-ray scattering (SAXS) has proven to be a valuable imaging technique of the nanoscale, for example of bone, teeth and brain matter. Although two-dimensional projection imaging has been used to characterize various materials successfully, its three-dimensional extension, SAXS computed tomography, poses substantial challenges, which have yet to be overcome. Previous work using SAXS computed tomography was unable to preserve oriented SAXS signals during reconstruction. Here we present a solution to this problem and obtain a complete SAXS computed tomography, which preserves oriented scattering information. By introducing virtual tomography axes, we take advantage of the two-dimensional SAXS information recorded on an area detector and use it to reconstruct the full three-dimensional scattering distribution in reciprocal space for each voxel of the three-dimensional object in real space. The presented method could be of interest for a combined six-dimensional real and reciprocal space characterization of mesoscopic materials with hierarchically structured features with length scales ranging from a few nanometres to a few millimetres—for example, biomaterials such as bone or teeth, or functional materials such as fuel-cell or battery components.

Six-dimensional real and reciprocal space small-angle X-ray scattering tomography.

PubMed

Schaff, Florian; Bech, Martin; Zaslansky, Paul; Jud, Christoph; Liebi, Marianne; Guizar-Sicairos, Manuel; Pfeiffer, Franz

2015-11-19

When used in combination with raster scanning, small-angle X-ray scattering (SAXS) has proven to be a valuable imaging technique of the nanoscale, for example of bone, teeth and brain matter. Although two-dimensional projection imaging has been used to characterize various materials successfully, its three-dimensional extension, SAXS computed tomography, poses substantial challenges, which have yet to be overcome. Previous work using SAXS computed tomography was unable to preserve oriented SAXS signals during reconstruction. Here we present a solution to this problem and obtain a complete SAXS computed tomography, which preserves oriented scattering information. By introducing virtual tomography axes, we take advantage of the two-dimensional SAXS information recorded on an area detector and use it to reconstruct the full three-dimensional scattering distribution in reciprocal space for each voxel of the three-dimensional object in real space. The presented method could be of interest for a combined six-dimensional real and reciprocal space characterization of mesoscopic materials with hierarchically structured features with length scales ranging from a few nanometres to a few millimetres--for example, biomaterials such as bone or teeth, or functional materials such as fuel-cell or battery components.

Computed Tomographic Blend Sign Is Associated With Computed Tomographic Angiography Spot Sign and Predicts Secondary Neurological Deterioration After Intracerebral Hemorrhage.

PubMed

Sporns, Peter B; Schwake, Michael; Schmidt, Rene; Kemmling, André; Minnerup, Jens; Schwindt, Wolfram; Cnyrim, Christian; Zoubi, Tarek; Heindel, Walter; Niederstadt, Thomas; Hanning, Uta

2017-01-01

Significant early hematoma growth in patients with intracerebral hemorrhage is an independent predictor of poor functional outcome. Recently, the novel blend sign (BS) has been introduced as a new imaging sign for predicting hematoma growth in noncontrast computed tomography. Another parameter predicting increasing hematoma size is the well-established spot sign (SS) visible in computed tomographic angiography. We, therefore, aimed to clarify the association between established SS and novel BS and their values predicting a secondary neurological deterioration. Retrospective study inclusion criteria were (1) spontaneous intracerebral hemorrhage confirmed on noncontrast computed tomography and (2) noncontrast computed tomography and computed tomographic angiography performed on admission within 6 hours after onset of symptoms. We defined a binary outcome (secondary neurological deterioration versus no secondary deterioration). As secondary neurological deterioration, we defined (1) early hemicraniectomy under standardized criteria or (2) secondary decrease of Glasgow Coma Scale of >3 points, both within the first 48 hours after symptom onset. Of 182 patients with spontaneous intracerebral hemorrhage, 37 (20.3%) presented with BS and 39 (21.4%) with SS. Of the 81 patients with secondary deterioration, 31 (38.3%) had BS and SS on admission. Multivariable logistic regression analysis identified hematoma volume (odds ratio, 1.07 per mL; P≤0.001), intraventricular hemorrhage (odds ratio, 3.08; P=0.008), and the presence of BS (odds ratio, 11.47; P≤0.001) as independent predictors of neurological deterioration. The BS, which is obtainable in noncontrast computed tomography, shows a high correlation with the computed tomographic angiography SS and is a reliable predictor of secondary neurological deterioration after spontaneous intracerebral hemorrhage. © 2016 American Heart Association, Inc.

Usefulness of 64-detector computed tomography in the diagnosis and management of patients with congenital heart disease.

PubMed

Bret-Zurita, Montserrat; Cuesta, Emilio; Cartón, Antonio; Díez, Jesús; Aroca, Ángel; Oliver, José M; Gutiérrez-Larraya, Federico

2014-11-01

Although congenital heart defects are the most common major congenital abnormalities, the associated mortality has been decreasing due to improvements in their diagnosis and treatment. We assessed the usefulness of 64-multidetector computed tomography in the diagnosis and management of these patients. This 5-year observational, analytical, retrospective, cohort study included a total of 222 tomographic studies of patients with congenital heart disease. Computed tomography scans were read twice and medical records were reviewed. We assessed the complexity of the disease, patient, and radiological technique, and evaluated the contribution of new data in relation to clinical suspicion and diagnostic change. A confidence interval was set at 95% and a P value of<.05 was used as the cutoff for statistical significance. In 35.1% of patients, the treatment procedure was performed after computed tomography without other tests. Additional diagnostic catheterization was performed in 12.5% of patients. There were new findings in 77% of patients (82.9% with complex disease), which prompted a change in patient management in 35.6%. All unexpected reports described new findings. No significant differences were found by age, sex, study period, urgency of the test order, patient complexity, or difficulty of the technique. Use of 64-detector computed tomography yields good diagnostic performance in congenital heart disease, prompts changes in management in more than one-third of patients, and reveals new findings in relation to the presumed diagnosis in 77% of patients. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Diagnostic accuracy of oblique chest radiograph for occult pneumothorax: comparison with ultrasonography.

PubMed

Matsumoto, Shokei; Sekine, Kazuhiko; Funabiki, Tomohiro; Orita, Tomohiko; Shimizu, Masayuki; Hayashida, Kei; Kazamaki, Taku; Suzuki, Tatsuya; Kishikawa, Masanobu; Yamazaki, Motoyasu; Kitano, Mitsuhide

2016-01-01

An occult pneumothorax is a pneumothorax that is not seen on a supine chest X-ray but is detected by computed tomography scanning. However, critical patients are difficult to transport to the computed tomography suite. We previously reported a method to detect occult pneumothorax using oblique chest radiography (OXR). Several authors have also reported that ultrasonography is an effective technique for detecting occult pneumothorax. The aim of this study was to evaluate the usefulness of OXR in the diagnosis of the occult pneumothorax and to compare OXR with ultrasonography. All consecutive blunt chest trauma patients with clinically suspected pneumothorax on arrival at the emergency department were prospectively included at our tertiary-care center. The patients underwent OXR and ultrasonography, and underwent computed tomography scans as the gold standard. Occult pneumothorax size on computed tomography was classified as minuscule, anterior, or anterolateral. One hundred and fifty-nine patients were enrolled. Of the 70 occult pneumothoraces found in the 318 thoraces, 19 were minuscule, 32 were anterior, and 19 were anterolateral. The sensitivity and specificity of OXR for detecting occult pneumothorax was 61.4 % and 99.2 %, respectively. The sensitivity and specificity of lung ultrasonography was 62.9 % and 98.8 %, respectively. Among 27 occult pneumothoraces that could not be detected by OXR, 16 were minuscule and 21 could be conservatively managed without thoracostomy. OXR appears to be as good method as lung ultrasonography in the detection of large occult pneumothorax. In trauma patients who are difficult to transfer to computed tomography scan, OXR may be effective at detecting occult pneumothorax with a risk of progression.