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1

Angiographic imaging evaluation of patient-specific bifurcation-aneurysm phantom treatment with pre-shaped, self-expanding, flow-diverting stents: feasibility study  

NASA Astrophysics Data System (ADS)

Aneurysm treatment using flow diversion could become the treatment of choice in the near future. While such side-wall aneurysm treatments have been studied in many publications and even implemented in selected clinical cases, bifurcation aneurysm treatment using flow diversion has not been addressed in detail. Using angiographic imaging, we evaluated treatment of such cases with several stent designs using patient-specific aneurysm phantoms. The aim is to find a way under fluoroscopic image guidance to place a low-porosity material across the aneurysm orifice while keeping the vessel blockage minimal. Three pre-shaped self-expanding stent designs were developed: the first design uses a middle-flap wing stent, the second uses a two-tapered-wing-ended stent, and the third is a slight modification of the first design in which the middle-flap is anchored tightly against the aneurysm using a standard stent. Treatment effects on flow were evaluated using high-speed angiography (30 fps) and compared with the untreated aneurysm. Contrast inflow was reduced in all the cases: 25% for Type 1, 63% for type 2 and 88% for Type 3. The first and the second stent design allowed some but substantially-reduced flow inside the aneurysm neck as indicated by the time-density curves. The third stent design eliminated almost all flow directed at the aneurysm dome, and only partial filling was observed. In the same time Type 1 and 3 delayed the inflow in the branches up to 100% compared to the untreated phantom. The results are quite promising and warrant future study.

Ionita, Ciprian N.; Suri, Himansu; Nataranjian, Sabareesh; Siddiqui, Adnan; Levy, Elad; Hopkins, Nelson L.; Bednarek, Daniel R.; Rudin, Stephen

2011-03-01

2

Potential risks and artifacts of magnetic resonance imaging of self-expandable esophageal stents  

Microsoft Academic Search

Background: Several types of coated and uncoated self-expandable stents composed of various metals are available for palliation of malignant esophageal stenoses and fistulas. We encountered poor visualization of the mediastinum and skeletal axis with magnetic resonance imaging in a patient with a Gianturco self-expandable stent. Methods: To evaluate potential problems, such as stent migration in the magnetic field of the

Babs G. Taal; Muller Sara; Henk Boot; Wim Koops

1997-01-01

3

Expanded beam non-imaging fiber optic connector  

DOEpatents

There is disclosed an expanded beam fiber to fiber connector, based on non-imaging optic principles for coupling light beams from one optical fiber to another. The system consists of two identical connector parts, referred to herein as a collimating part and a concentrating part, each having a preferred partially curved reflective boundary surface for minimizing power loss and surrounding either a hollow space or a space filled with a uniform transparent medium. In one embodiment the boundary is metallic while in a second embodiment the boundary is in the form of an interface allowing total internal reflection. In both the hollow and filled case a lens may be located at the expanded end of both the collimater part and the concentrator part forming the connector. The connector is preferably located in a housing in order to protect and preserve the mechanical stability of the coupler.

Jannson, Tommasz (Redondo Beach, CA); Jannson, Joanna (Redondo Beach, CA); Yeung, Peter (Redondo Beach, CA)

1990-01-01

4

As Patient Navigation Expands and Evolves, Nurses Assume Many Roles  

Cancer.gov

It can be difficult to access care in our labyrinthine health care system. Oncology nurses are joining the ranks of patient navigators—a diverse group of people who help patients at all stages of cancer care, from screening and diagnosis to treatment and survivorship.

5

Gene expression analysis of ex vivo expanded and freshly isolated NK cells from cancer patients.  

PubMed

The infusion of natural killer (NK) cells is a promising therapy for patients with advanced malignancies. Clinical expanded NK-cell products were compared with freshly isolated NK cells. Autologous peripheral blood mononuclear cells were collected by apheresis from 8 patients. NK cells were isolated by anti-CD3-negative selection followed by anti-CD56-positive selection. They were then expanded by co-culture with interleukin-2 and an irradiated Epstein-Barr virus (EBV)-transformed lymphoblastoid cell line (EBV-TM-LCL) to produce 14 NK-cell products. Molecular changes in the 14 NK-cell products were characterized using gene and microRNA expression microarrays. EBV-TM-LCL feeder cells from 3 lots were also analyzed as they were expanded for over 90 days and each lot was used for multiple NK-cell expansions. The gene expression profiles among the 3 EBV-TM-LCL lots used showed no differences and were not affected by their time in culture. Freshly isolated and expanded NK cells had distinct gene and microRNA expression profiles. Compared with fresh NK cells, expanded NK cells overexpressed 1098 genes and 28 human microRNAs. Genes in the crosstalk between dendritic and NK cells and metabolic pathways were up-regulated in expanded NK cells, whereas genes in a number of immune function pathways were down-regulated. Among all the most up-regulated genes were the NK cell-activating receptor natural cytotoxicity triggering receptor 3, myxovirus restistance 1, lymphotoxin ?, and BCL2-associated X protein. Although some expanded NK-cell product variability was observed, perhaps related to patient factors, further studies on larger numbers of products will be needed to determine the impact of these differences on clinical outcomes. PMID:20948442

Park, Kyoung Un; Jin, Ping; Sabatino, Marianna; Feng, Ji; Civini, Sara; Khuu, Hanh; Berg, Maria; Childs, Richard; Stroncek, David

2010-01-01

6

Does immediate tissue expander placement increase immediate postoperative complications in patients with breast cancer?  

PubMed

The objectives of this study were to evaluate 1) the rate of immediate breast reconstruction; 2) the frequency of immediate tissue expander placement; and 3) to compare perioperative outcomes in patients who underwent breast reconstruction after mastectomy for breast cancer with immediate tissue expander placement (TE) with those with no reconstruction (NR). Using the Nationwide Inpatient Sample database, we examined the clinical data of patients with breast cancer who underwent mastectomy with or without immediate TE from 2006 to 2010 in the United States. A total of 344,253 patients with breast cancer underwent mastectomy in this period in the United States. Of these patients, 31 per cent had immediate breast reconstruction. We only included patients with mastectomy and no reconstruction (NR: 237,825 patients) and patients who underwent only TE placement with no other reconstruction combination (TE: 61,178 patients) to this study. Patients in the TE group had a lower overall postoperative complication rate (2.6 vs 5.5%; P < 0.01) and lower in-hospital mortality rate (0.01 vs 0.09%; P < 0.01) compared with the NR group. Fifty-three per cent of patients in the NR group were discharged the day of surgery compared with 36 per cent of patients in the TE group. Using multivariate regression analyses and adjusting patient characteristics and comorbidities, patients in the TE group had a significantly lower overall complication rate (adjusted odds ratio [AOR], 0.6) and lower in-hospital mortality (AOR, 0.2) compared with the NR group. The rate of immediate reconstruction is 31 per cent. TE alone is the most common type of immediate reconstruction (57%). There is a lower complication rate for the patients who underwent immediate TE versus the no-reconstruction cohort. PMID:25642875

Masoomi, Hossein; Paydar, Keyianoosh Z; Evans, Gregory R D; Tan, Emily; Lane, Karen T; Wirth, Garrett A

2015-02-01

7

Photon beam dose distributions for patients with implanted temporary tissue expanders  

NASA Astrophysics Data System (ADS)

This study examines the effects of temporary tissue expanders (TTEs) on the dose distributions of photon beams in breast cancer radiotherapy treatments. EBT2 radiochromic film and ion chamber measurements were taken to quantify the attenuation and backscatter effects of the inhomogeneity. Results illustrate that the internal magnetic port present in a tissue expander causes a dose reduction of approximately 25% in photon tangent fields immediately downstream of the implant. It was also shown that the silicone elastomer shell of the tissue expander reduced the dose to the target volume by as much as 8%. This work demonstrates the importance for an accurately modelled high-density implant in the treatment planning system for post-mastectomy breast cancer patients.

Asena, A.; Kairn, T.; Crowe, S. B.; Trapp, J. V.

2015-01-01

8

Patient attitudes regarding the role of the pharmacist and interest in expanded pharmacist services  

PubMed Central

Background: Pharmacists are consistently ranked among the most trusted professionals, and research shows high levels of satisfaction with pharmacist services. Studies have also shown that the public is generally unaware of the full range of roles and responsibilities of a pharmacist. The purpose of this study was to explore the public’s knowledge and attitudes regarding the role of the community pharmacist and to determine their likelihood of using expanded pharmacist services. Methods: Adults across Newfoundland and Labrador were surveyed by telephone. Survey questions addressed how frequently participants visited the pharmacy, understanding of duties undertaken by pharmacists, perceptions and attitudes regarding pharmacists as health care professionals, likelihood of using expanded pharmacist services and participant demographics. Comparisons were made between responses from urban and rural participants and frequent versus nonfrequent pharmacy users, to determine if there were any differences. Results: The majority of participants were generally aware of what pharmacists do when filling prescriptions; those who visited the pharmacy more frequently appeared to be more informed. Participants indicated they would take advantage of the expanded services suggested, with greatest interest in receiving advice for minor ailment management and prescription refills from pharmacists. Results support the prevailing view that pharmacists are trusted health professionals who should have access to patients’ health information to provide best care. Conclusion: The public is aware of aspects of the pharmacist’s role, but opportunities exist to better educate the public on the knowledge, skills and unique professional abilities of pharmacists to support uptake of expanded pharmacist services. PMID:25360150

Young, Stephanie; Phillips, Leslie; Clark, Deidre

2014-01-01

9

Expanded image database of pistachio x-ray images and classification by conventional methods  

NASA Astrophysics Data System (ADS)

In order to develop sorting methods for insect damaged pistachio nuts, a large data set of pistachio x-ray images (6,759 nuts) was created. Both film and linescan sensor images were acquired, nuts dissected and internal conditions coded using the U.S. Grade standards and definitions for pistachios. A subset of 1199 good and 686 insect damaged nuts was used to calculate and test discriminant functions. Statistical parameters of image histograms were evaluated for inclusion by forward stepwise discrimination. Using three variables in the discriminant function, 89% of test set nuts were correctly identified. Comparable data for 6 human subjects ranged from 67 to 92%. If the loss of good nuts is held to 1% by requiring a high probability to discard a nut as insect damaged, approximately half of the insect damage present in clean pistachio nuts may be detected and removed by x-ray inspection.

Keagy, Pamela M.; Schatzki, Thomas F.; Le, Lan Chau; Casasent, David P.; Weber, David

1996-12-01

10

Expanding neurosurgery.  

PubMed

The history of medicine is replete with innovations in neurosurgery that have spurred further developments across the medical spectrum. Surgeons treating pathologies in the head and spine have broken ground with new approaches, techniques, and technologies since ancient times. Neurosurgeons occupy a vital nexus in patient care, interfacing with the clinical symptoms and signs afflicting patients, the pathology at surgery, and imaging studies. No other physicians occupy this role within the nervous system. This power of observation and the ability to intercede place neurosurgeons in a unique position for impacting disease. Yet despite these pioneering achievements, more recently, forces in the workplace may be challenging neurosurgery's opportunities to contribute to the future growth of the neurosciences and medicine. The authors posit that, in the current health care climate, revenue generation by neurosurgical clinical activity is valued by the system more than neurosurgical research and academic output. Without providing the talented stream of new neurosurgeons with the opportunities and, in fact, the directive to achieve beyond simple financial success, the specialty is missing the opportunity to optimize its progress. The authors contend that the key to remaining relevant with the incorporation of new technologies to the treatment of neurosurgical patients will be to be flexible, open-minded, and nimble with the adaptation of new procedures by training and encouraging neurosurgical residents to pursue new or neglected areas of the specialty. Only by doing so can neurosurgery continue to expand. PMID:25434710

Couldwell, William T; Mortimer, Vance; Kraus, Kristin L

2014-12-01

11

Use of two expanded-criteria-donor renal allografts in a single patient  

PubMed Central

The disparity between the number of available renal donors and the number of patients on the transplant waiting list has prompted the use of expanded-criteria-donor (ECD) renal allografts to expand the donor pool. ECD allografts have shown good results in appropriately selected recipients, yet a number of renal allografts are still discarded. The use of dual renal transplantation may lower the discard rate. Additionally, the use of perfusion systems may improve acute tubular necrosis rates with these allografts. We report a successful case of a dual transplant with ECD allografts using a perfusion system. The biopsy appearance and the pump characteristics were suboptimal for these kidneys, making them unsuitable for single transplantation; however, the pair of transplanted kidneys provided increased nephron mass and functioned well. We recommend that ECD kidneys that are individually nontransplantable be evaluated for potential dual renal transplantation. Biopsy criteria and perfusion data guidelines must be developed to improve the success rates with ECD dual renal allografts. Finally, recipient selection is of utmost importance. PMID:17637877

Fischbach, Bernard V.; Narasimhan, Gomathy; Chinnakotla, Srinath; Nikitin, Dmitriy; Khan, Tariq; Randall, Henry B.; McKenna, Gregory J.; Ruiz, Richard; Goldstein, Robert M.; Klintmalm, Göran B.; Levy, Marlon F.

2007-01-01

12

Thallium-201 stress imaging in hypertensive patients  

SciTech Connect

To assess the potential effect of hypertension on the results of thallium-201 stress imaging in patients with chest pain, 272 thallium-201 stress tests performed in 133 hypertensive patients and 139 normotensive patients over a 1-year period were reviewed. Normotensive and hypertensive patients were similar in age, gender distribution, prevalence of cardiac risk factors (tobacco smoking, hyperlipidemia, and diabetes mellitus), medications, and clinical symptoms of coronary disease. Electrocardiographic criteria for left ventricular hypertrophy were present in 16 hypertensive patients. Stepwise probability analysis was used to determine the likelihood of coronary artery disease for each patient. In patients with mid to high likelihood of coronary disease (greater than 25% probability), abnormal thallium-201 stress images were present in 54 of 60 (90%) hypertensive patients compared with 51 of 64 (80%) normotensive patients. However, in 73 patients with a low likelihood of coronary disease (less than or equal to 25% probability), abnormal thallium-201 stress images were present in 21 patients (29%) of the hypertensive group compared with only 5 of 75 (7%) of the normotensive patients (p less than 0.001). These findings suggest that in patients with a mid to high likelihood of coronary artery disease, coexistent hypertension does not affect the results of thallium-201 exercise stress testing. However, in patients with a low likelihood of coronary artery disease, abnormal thallium-201 stress images are obtained more frequently in hypertensive patients than in normotensive patients.

Schulman, D.S.; Francis, C.K.; Black, H.R.; Wackers, F.J.

1987-07-01

13

Aneurysmal Lesions of Patients with Abdominal Aortic Aneurysm Contain Clonally Expanded T Cells  

PubMed Central

Abdominal aortic aneurysm (AAA) is a common disease with often life-threatening consequences. This vascular disorder is responsible for 1–2% of all deaths in men aged 65 years or older. Autoimmunity may be responsible for the pathogenesis of AAA. Although it is well documented that infiltrating T cells are essentially always present in AAA lesions, little is known about their role in the initiation and/or progression of the disease. To determine whether T cells infiltrating AAA lesions contain clonally expanded populations of T cells, we amplified ?-chain TCR transcripts by the nonpalindromic adaptor–PCR/V?-specific PCR and/or V?-specific PCR, followed by cloning and sequencing. We report in this article that aortic abdominal aneurysmal lesions from 8 of 10 patients with AAA contained oligoclonal populations of T cells. Multiple identical copies of ?-chain TCR transcripts were identified in these patients. These clonal expansions are statistically significant. These results demonstrate that ?? TCR+ T lymphocytes infiltrating aneurysmal lesions of patients with AAA have undergone proliferation and clonal expansion in vivo at the site of the aneurysmal lesion, in response to unidentified self- or nonself Ags. This evidence supports the hypothesis that AAA is a specific Ag–driven T cell disease. PMID:24752442

Lu, Song; White, John V.; Lin, Wan Lu; Zhang, Xiaoying; Solomides, Charalambos; Evans, Kyle; Ntaoula, Nectaria; Nwaneshiudu, Ifeyinwa; Gaughan, John; Monos, Dimitri S.; Oleszak, Emilia L.

2014-01-01

14

Spectroscopic, imaging, and probe diagnostics of laser plasma plumes expanding between confining surfaces  

SciTech Connect

Laser plasma plumes were generated in aluminum rectangular cavities of fixed depth (6 mm) and varying height (2.0, 1.5, and 1.0 mm). Space and time resolved visible emission spectroscopy, gated intensified visible imaging, and Langmuir probe diagnostics were utilized to diagnose the evolution of the confined plasma plumes in comparison to freely expanding plasma plume generated from ablation of a planar target. The constrained plasma behavior displayed a multiphase history. Early stage interactions (t<100 ns) resulted in enhanced continuum and line emission, shockwave formation and plasma plume rebound. Later phase, long duration plasma-surface interactions (t>160 ns) resulted in sustained 'decay', i.e., a rapid termination of continuum emission, in concert with decreases in peak electron density (N{sub e}) and plasma temperature (T). This later phase originates from loss mechanisms which bleed the plasma plume of thermal energy and charged particles. These loss mechanisms increase in magnitude as the duration of the plasma-surface interaction increases. The transition from enhancement phase, originating from hydrodynamic containment, and plasma-surface collisions, to decay phase is described and occurs for each cavity at a different point in the space time history.

Yeates, P. [National Centre for Plasma Science and Technology, Dublin City University, Dublin 9 (Ireland); Kennedy, E. T. [School of Physical Sciences, Dublin City University, Dublin 9 (Ireland)

2010-11-15

15

Postoperative spine imaging in cancer patients.  

PubMed

Primary or metastatic spine tumors can present with pain and/or neurologic compromise depending on their location within the spinal axis. Metastases and multiple myeloma comprise most of these lesions. Management of spinal tumors includes surgical decompression with stabilization (neo), adjuvant chemotherapy and radiation therapy, curettage, bone grafting, bone marrow replacement, and palliative treatment with vertebral augmentation. Pre- and postoperative imaging plays a critical role in the diagnosis and management of patients with spinal tumors. This article reviews postoperative imaging of the spine, including imaging protocols, immediate and long-term routine imaging findings, and emergent findings in symptomatic patients. PMID:24792611

Coronel, Esther E; Lien, Ruby J; Ortiz, A Orlando

2014-05-01

16

Immunophenotypic and functional characterization of ex vivo expanded natural killer cells for clinical use in acute lymphoblastic leukemia patients.  

PubMed

The management of acute lymphoblastic leukemia (ALL) patients has witnessed profound changes in recent years. Nonetheless, most patients tend to relapse, underlining the need for new therapeutic approaches. The anti-leukemic potential of natural killer (NK) cells has over the years raised considerable interest. In this study, we developed an efficient method for the expansion and activation of NK cells isolated from healthy donors and ALL patients for clinical use. NK cell products were derived from peripheral blood mononuclear cells of 35 healthy donors and 4 B-lineage ALL by immunomagnetic CD3 T cell depletion followed by CD56 cell enrichment. Isolated NK cells were expanded and stimulated in serum-free medium supplemented with irradiated autologous feeder cells and autologous plasma in the presence of clinical grade interleukin (IL)-2 and IL-15 for 14 days. Healthy donor NK cells expanded on average 34.9 ± 10.4 fold and were represented, after expansion, by a highly pure population of CD3(-)CD56(+) cells showing a significant upregulation of natural cytotoxicity receptors, activating receptors and maturation markers. These expanded effectors showed cytolytic activity against K562 cells and, most importantly, against primary adult B-lineage ALL blasts. NK cells could be efficiently isolated and expanded-on average 39.5 ± 20.3 fold-also from primary B-lineage ALL samples of patients in complete remission. The expanded NK cells from these patients showed a significantly increased expression of the NKG2D- and DNAM1-activating receptors and were cytotoxic against K562 cells. These data provide the basis for developing new immunotherapeutic strategies for the management of ALL patients. PMID:25341808

Peragine, Nadia; Torelli, Giovanni F; Mariglia, Paola; Pauselli, Simona; Vitale, Antonella; Guarini, Anna; Foà, Robin

2015-02-01

17

Transapical Aortic Valve Replacement under Real-time Magnetic Resonance Imaging Guidance: Experimental Results with Balloon-Expandable and Self-Expanding Stents  

PubMed Central

Objective Aortic valves have been implanted on self-expanding (SE) and balloon-expandable (BE) stents minimally invasively. We have demonstrated the advantages of transapical aortic valve implantation (tAVI) under real-time magnetic resonance imaging (rtMRI) guidance. Whether there are different advantages to SE or BE stents is unknown. We report rtMRI guided tAVI in a porcine model using both SE and BE stents, and compare the differences between the stents. Methods Twenty-two Yucatan pigs (45-57kgs.) underwent tAVI. Commercially available stentless bioprostheses (21-25mm) were mounted on either BE platinum-iridium stents or SE nitinol stents. rtMRI guidance was employed as the intraoperative imaging. Markers on both types of stents were used to enhance the visualization in rtMRI. Pigs were allowed to survive and had follow-up MRI scans and echocardiography at 1, 3 and 6 months postoperatively. Results rtMRI provided excellent visualization of the aortic valve implantation mounted on both stent types. The implantation times were shorter with the SE stents (60±14 seconds) than BE (74±18s), (p=0.027). Total procedure time was 31 and 37 minutes respectively (p=0.12). It was considerably easier to manipulate the SE stent during deployment without hemodynamic compromise. This was not always the case with the BE stent and its placement occasionally resulted in coronary obstruction and death. Long-term results demonstrated stability of the implants with preservation of myocardial perfusion and function over time for both stents. Conclusions SE stents were easier to position and deploy thus leading to fewer complications during tAVI. Future optimization of SE stent design should improve clinical results. PMID:20971017

Horvath, Keith A.; Mazilu, Dumitru; Kocaturk, Ozgur; Li, Ming

2010-01-01

18

Serious Complications after Self-expandable Metallic Stent Insertion in a Patient with Malignant Lymphoma  

PubMed Central

An 18-year-old woman was evaluated for a chronic productive cough and dyspnea. She was subsequently diagnosed with mediastinal non-Hodgkin lymphoma (NHL). A covered self-expandable metallic stent (SEMS) was implanted to relieve narrowing in for both main bronchi. The NHL went into complete remission after six chemotherapy cycles, but atelectasis developed in the left lower lobe 18 months after SEMS insertion. The left main bronchus was completely occluded by granulation tissue. However, the right main bronchus and intermedius bronchus were patent. Granulation tissue was observed adjacent to the SEMS. The granulation tissue and the SEMS were excised, and a silicone stent was successfully implanted using a rigid bronchoscope. SEMS is advantageous owing to its easy implantation, but there are considerable potential complications such as severe reactive granulation, stent rupture, and ventilation failure in serious cases. Therefore, SEMS should be avoided whenever possible in patients with benign airway disease. This case highlights that SEMS implantation should be avoided even in malignant airway obstruction cases if the underlying malignancy is curable. PMID:25653695

Cho, Sung Bae; Cha, Seon Ah; Choi, Joon Young; Lee, Jong Min; Kang, Hyeon Hui; Moon, Hwa Sik; Kim, Sei Won; Yeo, Chang Dong

2015-01-01

19

Axon reactive B cells clonally expanded in the cerebrospinal fluid of patients with multiple sclerosis.  

PubMed

Demyelination and axonal loss have been described as the histological hallmarks of inflammatory lesions of multiple sclerosis (MS) and are the pathological correlates of persistent disability. However, the immune mechanisms underlying axonal damage in MS remain unknown. Here, we report the use of single chain-variable domain fragments (scFv) from clonally expanded cerebrospinal fluid (CSF) B cells to show the role of an anti-axon immune response in the central nervous system (CNS) in MS. The cellular and subcellular distribution of the antigen(s) recognized by these CSF-derived clonal scFv antibodies (CSFC-scFv Abs) was studied by immunochemical staining of brain tissues obtained at autopsy from patients with MS. Immunochemistry showed specific binding of CSFC-scFv Abs to axons in acute MS lesions. The stained axons showed three major types of axonal pathological changes: 1) linear axons, axonal ovoid formation, and axonal transection were seen in the myelinated white matter adjacent to the lesion; 2) accumulation of axonal ovoid formations and Wallerian degeneration were seen at the border between demyelinated lesions and the adjacent white matter; and 3) Wallerian degeneration occurred at the center and edge of acute demyelinated lesions. These findings suggest a B cell axonal specific immune response in the CNS in MS. PMID:15981091

Zhang, Yiping; Da, Reng-Rong; Guo, Wenzhong; Ren, Hui-Min; Hilgenberg, Lutz G; Sobel, Raymond A; Tourtellotte, Wallace W; Smith, Martin A; Olek, Michael; Gupta, Sudhir; Robertson, Richard T; Nagra, Rashed; Van Den Noort, Stanley; Qin, Yufen

2005-05-01

20

Serious Complications after Self-expandable Metallic Stent Insertion in a Patient with Malignant Lymphoma.  

PubMed

An 18-year-old woman was evaluated for a chronic productive cough and dyspnea. She was subsequently diagnosed with mediastinal non-Hodgkin lymphoma (NHL). A covered self-expandable metallic stent (SEMS) was implanted to relieve narrowing in for both main bronchi. The NHL went into complete remission after six chemotherapy cycles, but atelectasis developed in the left lower lobe 18 months after SEMS insertion. The left main bronchus was completely occluded by granulation tissue. However, the right main bronchus and intermedius bronchus were patent. Granulation tissue was observed adjacent to the SEMS. The granulation tissue and the SEMS were excised, and a silicone stent was successfully implanted using a rigid bronchoscope. SEMS is advantageous owing to its easy implantation, but there are considerable potential complications such as severe reactive granulation, stent rupture, and ventilation failure in serious cases. Therefore, SEMS should be avoided whenever possible in patients with benign airway disease. This case highlights that SEMS implantation should be avoided even in malignant airway obstruction cases if the underlying malignancy is curable. PMID:25653695

Cho, Sung Bae; Cha, Seon Ah; Choi, Joon Young; Lee, Jong Min; Kang, Hyeon Hui; Moon, Hwa Sik; Kim, Sei Won; Yeo, Chang Dong; Lee, Sang Haak

2015-01-01

21

Image navigation as a means to expand the boundaries of fluorescence-guided surgery  

NASA Astrophysics Data System (ADS)

Hybrid tracers that are both radioactive and fluorescent help extend the use of fluorescence-guided surgery to deeper structures. Such hybrid tracers facilitate preoperative surgical planning using (3D) scintigraphic images and enable synchronous intraoperative radio- and fluorescence guidance. Nevertheless, we previously found that improved orientation during laparoscopic surgery remains desirable. Here we illustrate how intraoperative navigation based on optical tracking of a fluorescence endoscope may help further improve the accuracy of hybrid surgical guidance. After feeding SPECT/CT images with an optical fiducial as a reference target to the navigation system, optical tracking could be used to position the tip of the fluorescence endoscope relative to the preoperative 3D imaging data. This hybrid navigation approach allowed us to accurately identify marker seeds in a phantom setup. The multispectral nature of the fluorescence endoscope enabled stepwise visualization of the two clinically approved fluorescent dyes, fluorescein and indocyanine green. In addition, the approach was used to navigate toward the prostate in a patient undergoing robot-assisted prostatectomy. Navigation of the tracked fluorescence endoscope toward the target identified on SPECT/CT resulted in real-time gradual visualization of the fluorescent signal in the prostate, thus providing an intraoperative confirmation of the navigation accuracy.

Brouwer, Oscar R.; Buckle, Tessa; Bunschoten, Anton; Kuil, Joeri; Vahrmeijer, Alexander L.; Wendler, Thomas; Valdés-Olmos, Renato A.; van der Poel, Henk G.; van Leeuwen, Fijs W. B.

2012-05-01

22

Efficacy of ex vivo activated and expanded natural killer cells and T lymphocytes for colorectal cancer patients.  

PubMed

Immune cell-based therapies using natural killer (NK) cells and cytotoxic T cells are under constant scrutiny, with the aim to design an effective and reduced-toxicity therapy, which will benefit patients via improved quality of life and improved prognosis. Four patients with stage IV colon cancer were administered 1, 3, 5 and 6 effector cell intravenous infusions, respectively. Peripheral blood was collected from the patients and the ex vivo activation and expansion of NK and T cells was performed in Good Manufacturing Practice-certified clean rooms for ~12-15 days. Immunophenotypic analysis of the peripheral blood mononuclear cells (PBMCs) and expanded NK and T cells was conducted using flow cytometry and the patients were followed up. On average, 4.8×10(7) initial PBMCs and 2.7×10(9) total expanded cells were obtained. The intravenous infusions of the expanded cells were not accompanied by adverse reactions. Improved prognosis, reflected by a considerable decrease in the cancer markers, accompanied by an improved quality of life in the patients were observed. In conclusion, potential strategies are currently under development for the large-scale production of effectors cells; therefore, autologous immune enhancement therapy (AIET) may be considered as a viable approach to cancer treatment. PMID:24944796

Subramani, Baskar; Pullai, Chithra Ramanathan; Krishnan, Kohila; Sugadan, Sheela Devi; Deng, Xuewen; Hiroshi, Terunuma; Ratnavelu, Kananathan

2014-07-01

23

Isolation and characterization of ex vivo expanded mesenchymal stem cells obtained from a surgical patient  

PubMed Central

The aim of the present study was to investigate the morphological characteristics and pluripotent differentiation potential of human bone marrow mesenchymal stem cells (hBMMSCs) in vitro and in vivo. Bone marrow cells were isolated from a rib fragment of an adult surgical patient, hBMMSCs were isolated based on plastic adherence and expanded ex vivo and phenotyping was performed. Pluripotent differentiation assays for adipogenesis, myogenesis and osteogenesis were conducted. Hematopoietic reconstruction of sublethally irradiated nude mice was performed by infusion of hBMMSCs. The gene expression profiles of early and late hBMMSCs were examined. The rate of CD31-positive cells was 31.1% in passage (P)4 hBMMSCs and 18.6% in P10 hBMMSCs. CD105 and CD106 were expressed in 99 and 95% of P25 hBMMSCs, respectively. Lipid droplets appeared at day 18 post induction. For osteogenesis, palpable masses were grossly observed from day 35 post inoculation of hBMMSCs. Hematoxylin and eosin staining further revealed chondrocytes and bone tissues. For myogenesis, at day six post subcutaneous inoculation, hBMMSCs differentiated into myocytes and were positive for myoglobin and MyoD1. In irradiated nude mice reconstituted by hBMMSCs, the white blood cell count briefly decreased following irradiation; however, it gradually recovered. In the irradiated nude mice reconstituted with hBMMSCs, CD45- and CD34-positive cells were detected 72 h post induction. Gene microarray analysis of P7 and P57 hBMMSCs demonstrated that 20 genes were upregulated >2 fold and 40 genes were downregulated >2 fold in P57 hBMMSCs. In conclusion, the isolated HBMMSCs possessed pluripotent differentiation potential and it was feasible and safe to use hBMMSCs within 30 passages. PMID:25376882

HUANG, JIA; SHA, HUIFAN; WANG, GUAN; BAO, GUOLIANG; LU, SHUN; LUO, QINGQUAN; TAN, QIANG

2015-01-01

24

Isolation and characterization of ex vivo expanded mesenchymal stem cells obtained from a surgical patient.  

PubMed

The aim of the present study was to investigate the morphological characteristics and pluripotent differentiation potential of human bone marrow mesenchymal stem cells (hBMMSCs) in vitro and in vivo. Bone marrow cells were isolated from a rib fragment of an adult surgical patient, hBMMSCs were isolated based on plastic adherence and expanded ex vivo and phenotyping was performed. Pluripotent differentiation assays for adipogenesis, myogenesis and osteogenesis were conducted. Hematopoietic reconstruction of sublethally irradiated nude mice was performed by infusion of hBMMSCs. The gene expression profiles of early and late hBMMSCs were examined. The rate of CD31?positive cells was 31.1% in passage (P)4 hBMMSCs and 18.6% in P10 hBMMSCs. CD105 and CD106 were expressed in 99 and 95% of P25 hBMMSCs, respectively. Lipid droplets appeared at day 18 post induction. For osteogenesis, palpable masses were grossly observed from day 35 post inoculation of hBMMSCs. Hematoxylin and eosin staining further revealed chondrocytes and bone tissues. For myogenesis, at day six post subcutaneous inoculation, hBMMSCs differentiated into myocytes and were positive for myoglobin and MyoD1. In irradiated nude mice reconstituted by hBMMSCs, the white blood cell count briefly decreased following irradiation; however, it gradually recovered. In the irradiated nude mice reconstituted with hBMMSCs, CD45? and CD34?positive cells were detected 72 h post induction. Gene microarray analysis of P7 and P57 hBMMSCs demonstrated that 20 genes were upregulated >2 fold and 40 genes were downregulated >2 fold in P57 hBMMSCs. In conclusion, the isolated HBMMSCs possessed pluripotent differentiation potential and it was feasible and safe to use hBMMSCs within 30 passages. PMID:25376882

Huang, Jia; Sha, Huifan; Wang, Guan; Bao, Guoliang; Lu, Shun; Luo, Qingquan; Tan, Qiang

2015-03-01

25

Ex Vivo-expanded Natural Killer Cells Demonstrate Robust Proliferation In Vivo in High-risk Relapsed Multiple Myeloma Patients.  

PubMed

Highly activated/expanded natural killer (NK) cells can be generated by stimulation with the human leukocyte antigen-deficient cell line K562, genetically modified to express 41BB-ligand and membrane-bound interleukin (IL)15. We tested the safety, persistence, and activity of expanded NK cells generated from myeloma patients (auto-NK) or haploidentical family donors (allo-NK) in heavily pretreated patients with high-risk relapsing myeloma. The preparative regimen comprised bortezomib only or bortezomib and immunosuppression with cyclophosphamide, dexamethasone, and fludarabine. NK cells were shipped overnight either cryopreserved or fresh. In 8 patients, up to 1×10 NK cells/kg were infused on day 0 and followed by daily administrations of IL2. Significant in vivo expansion was observed only in the 5 patients receiving fresh products, peaking at or near day 7, with the highest NK-cell counts in 2 subjects who received cells produced in a high concentration of IL2 (500 U/mL). Seven days after infusion, donor NK cells comprised >90% of circulating leukocytes in fresh allo-NK cell recipients, and cytolytic activity against allogeneic myeloma targets was retained in vitro. Among the 7 evaluable patients, there were no serious adverse events that could be related to NK-cell infusion. One patient had a partial response and in another the tempo of disease progression decreased; neither patient required further therapy for 6 months. In the 5 remaining patients, disease progression was not affected by NK-cell infusion. In conclusion, infusion of large numbers of expanded NK cells was feasible and safe; infusing fresh cells was critical to their expansion in vivo. PMID:25415285

Szmania, Susann; Lapteva, Natalia; Garg, Tarun; Greenway, Amy; Lingo, Joshuah; Nair, Bijay; Stone, Katie; Woods, Emily; Khan, Junaid; Stivers, Justin; Panozzo, Susan; Campana, Dario; Bellamy, William T; Robbins, Molly; Epstein, Joshua; Yaccoby, Shmuel; Waheed, Sarah; Gee, Adrian; Cottler-Fox, Michele; Rooney, Cliona; Barlogie, Bart; van Rhee, Frits

2015-01-01

26

Antigen Specificity of Clonally Expanded and Receptor Edited Cerebrospinal Fluid B cells from Patients with Relapsing Remitting MS  

PubMed Central

We re-engineered the immunoglobulin rearrangements from clonally expanded CSF B cells of three Multiple Sclerosis patients as Fab fragments, and used three methods to test for their Ag-specificity. Nine out of ten Fab fragments were reactive to Myelin Basic Protein (MBP). The one Fab that did not react to MBP was a product of receptor editing. Two of the nine MBP-reactive Fabs were also reactive to GFAP and CNPase, indicating that these clones were polyreactive. Targeting the mechanisms that allows these self-reactive B cells to reside in the CSF of MS patients may prove to be a potent immunotherapeutic strategy. PMID:17451814

Lambracht-Washington, Doris; O’Connor, Kevin C.; Cameron, Elizabeth; Jowdry, Andrea; Ward, E. Sally; Frohman, Elliot; Racke, Michael K.; Monson, Nancy L.

2009-01-01

27

Axon Reactive B Cells Clonally Expanded in the Cerebrospinal Fluid of Patients with Multiple Sclerosis  

Microsoft Academic Search

Demyelination and axonal loss have been described as the histological hallmarks of inflammatory lesions of multiple sclerosis (MS) and are the pathological correlates of persistent disability. However, the immune mechanisms underlying axonal damage in MS remain unknown. Here, we report the use of single chain-variable domain fragments (scFv) from clonally expanded cerebrospinal fluid (CSF) B cells to show the role

Yiping Zhang; Reng-Rong Da; Wenzhong Guo; Hui-Min Ren; Lutz G. Hilgenberg; Raymond A. Sobel; Wallace W. Tourtellotte; Martin A. Smith; Michael Olek; Sudhir Gupta; Richard T. Robertson; Rashed Nagra; Stanley Van Den Noort; Yufen Qin

2005-01-01

28

Specific lymphocyte subsets predict response to adoptive cell therapy using expanded autologous tumor-infiltrating lymphocytes in metastatic melanoma patients  

PubMed Central

Purpose Adoptive cell therapy (ACT) using autologous tumor-infiltrating lymphocytes (TIL) is a promising treatment for metastatic melanoma unresponsive to conventional therapies. We report here on the results of an ongoing Phase II clinical trial testing the efficacy of ACT using TIL in metastatic melanoma patients and the association of specific patient clinical characteristics and the phenotypic attributes of the infused TIL with clinical response. Experimental Design Altogether, 31 transiently lymphodepleted patients were treated with their expanded TIL followed by two cycles of high-dose (HD) IL-2 therapy. The effects of patient clinical features and the phenotypes of the T-cells infused on clinical response were determined. Results Overall, 15/31 (48.4%) patients had an objective clinical response using immune-related response criteria (irRC), with two patients (6.5%) having a complete response. Progression-free survival of >12 months was observed for 9/15 (60%) of the responding patients. Factors significantly associated with objective tumor regression included a higher number of TIL infused, a higher proportion of CD8+ T-cells in the infusion product, a more differentiated effector phenotype of the CD8+ population and a higher frequency of CD8+ T-cells co-expressing the negative costimulation molecule “B- and T-lymphocyte attenuator” (BTLA). No significant difference in telomere lengths of TIL between responders and non-responders was identified. Conclusion These results indicate that immunotherapy with expanded autologous TIL is capable of achieving durable clinical responses in metastatic melanoma patients and that CD8+ T-cells in the infused TIL, particularly differentiated effectors cells and cells expressing BTLA, are associated with tumor regression. PMID:23032743

Radvanyi, Laszlo G.; Bernatchez, Chantale; Zhang, Minying; Fox, Patricia S.; Miller, Priscilla; Chacon, Jessica; Wu, Richard; Lizee, Gregory; Mahoney, Sandy; Alvarado, Gladys; Glass, Michelle; Johnson, Valen E.; McMannis, John D.; Shpall, Elizabeth; Prieto, Victor; Papadopoulos, Nicholas; Kim, Kevin; Homsi, Jade; Bedikian, Agop; Hwu, Wen-Jen; Patel, Sapna; Ross, Merrick I.; Lee, Jeffrey E.; Gershenwald, Jeffrey E.; Lucci, Anthony; Royal, Richard; Cormier, Janice N.; Davies, Michael A.; Mansaray, Rahmatu; Fulbright, Orenthial J.; Toth, Christopher; Ramachandran, Renjith; Wardell, Seth; Gonzalez, Audrey; Hwu, Patrick

2012-01-01

29

A Pilot Imaging Line Survey of RW LMi and IK Tau Using the Expanded Very Large Array  

NASA Astrophysics Data System (ADS)

We report on a pilot imaging line survey (36.0-37.0 GHz, with ~1 km s-1 spectral channels) with the Expanded Very Large Array for two asymptotic giant branch stars, RW LMi (= CIT6, which has a carbon-rich circumstellar envelope, CSE) and IK Tau (=NML Tau, with an oxygen-rich CSE). Radio continuum emission consistent with photospheric emission was detected from both stars. From RW LMi we imaged the HC3N (J = 4?3) emission. The images show several partial rings of emission; these multiple shells trace the evolution of the CSE from 400 to 1200 years. SiS (J = 2?1) emission was detected from both RW LMi and IK Tau. For both stars the SiS emission is centrally condensed with the peak line emission coincident with the stellar radio continuum emission. In addition, we have detected weak HC7N (J = 32?31) emission from RW LMi.

Claussen, M. J.; Sjouwerman, L. O.; Rupen, M. P.; Olofsson, H.; Schöier, F. L.; Bergman, P.; Knapp, G. R.

2011-09-01

30

HLA-haploidentical bone marrow transplantation with posttransplant cyclophosphamide expands the donor pool for patients with sickle cell disease.  

PubMed

Allogeneic marrow transplantation can cure sickle cell disease; however, HLA-matched donors are difficult to find, and the toxicities of myeloablative conditioning are prohibitive for most adults with this disease. We developed a nonmyeloablative bone marrow transplantation platform using related, including HLA-haploidentical, donors for patients with sickle cell disease. The regimen consisted of antithymocyte globulin, fludarabine, cyclophosphamide, and total body irradiation, and graft-versus-host disease prophylaxis with posttransplantation high-dose cyclophosphamide, mycophenolate mofetil, and tacrolimus or sirolimus. After screening 19 patients, we transplanted 17, 14 from HLA-haploidentical and 3 from HLA-matched related donors. Eleven patients engrafted durably. With a median follow-up of 711 days (minimal follow up 224 days), 10 patients are asymptomatic, and 6 patients are off immunosupression. Only 1 patient developed skin-only acute graft-versus-host disease that resolved without any therapy; no mortality was seen. Nonmyeloablative conditioning with posttransplantation high-dose cyclophosphamide expands the donor pool, making marrow transplantation feasible for most patients with sickle cell disease, and is associated with a low risk of complications, even with haploidentical related donors. Graft failure, 43% in haploidentical pairs, remains a major obstacle but may be acceptable in a fraction of patients if the majority can be cured without serious toxicities. PMID:22955919

Bolaños-Meade, Javier; Fuchs, Ephraim J; Luznik, Leo; Lanzkron, Sophie M; Gamper, Christopher J; Jones, Richard J; Brodsky, Robert A

2012-11-22

31

Patient requests for office-based imaging.  

PubMed

The rising cost of health care affects our economy and can impact the health of our citizens. Costs can be divided into direct costs, which are incurred in the provision of services and procedures, and ancillary costs, such as labs and imaging. While ancillary services greatly assist providers in diagnosing and treating medical conditions, they can be overused or inappropriately used and can lead to adverse events. All providers should work to order the most appropriate imaging and tests and to protect patients at all times. PMID:24663139

Flick, Conrad L

2014-01-01

32

Prospectively versus retrospectively ECG-gated 256-slice coronary CT angiography: image quality and radiation dose over expanded heart rates  

Microsoft Academic Search

To compare image quality and radiation dose estimates for coronary computed tomography angiography (CCTA) obtained with a\\u000a prospectively gated transaxial (PGT) CT technique and a retrospectively gated helical (RGH) CT technique using a 256-slice\\u000a multidetector CT (MDCT) scanner and establish an upper limit of heart rate to achieve reliable diagnostic image quality using\\u000a PGT. 200 patients (135 males, 65 females)

Yang HouYong; Yong Yue; Wenli Guo; Guoqiang Feng; Tao Yu; Guangwei Li; Mani Vembar; Mark E. Olszewski; Qiyong Guo

33

Analysis of Teladoc use seems to indicate expanded access to care for patients without prior connection to a provider.  

PubMed

Despite the potential benefits of telehealth applications, little is known about their overall impact on care. This is critical because rising health care costs and a shortage of primary care providers make it likely that telehealth services will play an increasingly important role in health care delivery. To help fill this gap in knowledge, we describe early experiences with Teladoc, one of the largest telemedicine providers in the United States, which provides care directly to patients over the telephone or via the Internet. We analyzed claims data for a large California agency serving public employees that recently offered Teladoc as a covered service. The 3,701 Teladoc "visits" we studied were for a broad range of diagnostic categories, the most common of which were acute respiratory conditions, urinary tract infections, and skin problems. Compared to patients who visited a physician's office for a similar condition, adult Teladoc users were younger and less likely to have used health care before the introduction of Teladoc. Patients who used Teladoc were less likely to have a follow-up visit to any setting, compared to those patients who visited a physician's office or emergency department. Teladoc appears to be expanding access to patients who are not connected to other providers. Future research should assess the impact of Teladoc and other telehealth interventions on the quality and cost of care. PMID:24493769

Uscher-Pines, Lori; Mehrotra, Ateev

2014-02-01

34

Four-Year Treatment Outcomes of Adult Patients Enrolled in Mozambique's Rapidly Expanding Antiretroviral Therapy Program  

PubMed Central

Background In Mozambique during 2004–2007 numbers of adult patients (?15 years old) enrolled on antiretroviral therapy (ART) increased about 16-fold, from <5,000 to 79,500. All ART patients were eligible for co-trimoxazole. ART program outcomes, and determinants of outcomes, have not yet been reported. Methodology/Principal Findings In a retrospective cohort study, we investigated rates of mortality, attrition (death, loss to follow-up, or treatment cessation), immunologic treatment failure, and regimen-switch, as well as determinants of selected outcomes, among a nationally representative sample of 2,596 adults initiating ART during 2004–2007. At ART initiation, median age of patients was 34 and 62% were female. Malnutrition and advanced disease were common; 18% of patients weighed <45 kilograms, and 15% were WHO stage IV. Median baseline CD4+ T-cell count was 153/µL and was lower for males than females (139/µL vs. 159/µL, p<0.01). Stavudine, lamivudine, and nevirapine or efavirenz were prescribed to 88% of patients; only 31% were prescribed co-trimoxazole. Mortality and attrition rates were 3.4 deaths and 19.8 attritions per 100 patient-years overall, and 12.9 deaths and 57.2 attritions per 100 patient-years in the first 90 days. Predictors of attrition included male sex [adjusted hazard ratio (AHR) 1.5; 95% confidence interval (CI), 1.3–1.8], weight <45 kg (AHR 2.1; 95% CI, 1.6–2.9, reference group >60 kg), WHO stage IV (AHR 1.7; 95% CI, 1.3–2.4, reference group WHO stage I/II), lack of co-trimoxazole prescription (AHR 1.4; 95% CI, 1.0–1.8), and later calendar year of ART initiation (AHR 1.5; 95% CI, 1.2–1.8). Rates of immunologic treatment failure and regimen-switch were 14.0 and 0.6 events per 100-patient years, respectively. Conclusions ART initiation at earlier disease stages and scale-up of co-trimoxazole among ART patients could improve outcomes. Research to determine reasons for low regimen-switch rates and increasing rates of attrition during program expansion is needed. PMID:21483703

Auld, Andrew F.; Mbofana, Francisco; Shiraishi, Ray W.; Sanchez, Mauro; Alfredo, Charity; Nelson, Lisa J.; Ellerbrock, Tedd

2011-01-01

35

Near infra-red photoluminescent graphene nanoparticles greatly expand their use in noninvasive biomedical imaging.  

PubMed

A simple reaction process is developed to synthesize blue, green, yellow and red colour graphene nanoparticles (GNPs) from carbon fibers. Here, we have focused on synthesis of near infra-red GNPs and their biological application for optical imaging of deep tissues and organs. PMID:23624441

Nurunnabi, Md; Khatun, Zehedina; Reeck, Gerald R; Lee, Dong Yun; Lee, Yong-kyu

2013-06-01

36

Designing the Expanded Programme on Immunisation (EPI) as a service: Prioritising patients over administrative logic.  

PubMed

Expanded Programme on Immunisation (EPI) vaccination rates remain well below herd immunity in regions of many countries despite huge international resources devoted to both financing and access. We draw upon service marketing theory, organisational sociology, development anthropology and cultural consumer research to conduct an ethnographic study of vaccination delivery in Jimma Zone, Ethiopia - one such region. We find that Western public health sector policies are dominated by an administrative logic. Critical failures in delivery are produced by a system that obfuscates the on-the-ground problems that mothers face in trying to vaccinate their children, while instead prioritising administrative processes. Our ethnographic analysis of 83 mothers who had not vaccinated their children reveals key barriers to vaccination from a 'customer' perspective. While mothers value vaccination, it is a 'low involvement' good compared to the acute daily needs of a subsistence life. The costs imposed by poor service - such as uncaring staff with class hostilities, unpredictable and missed schedules and long waits - are too much and so they forego the service. Our service design framework illuminates specific service problems from the mother's perspective and points towards simple service innovations that could improve vaccination rates in regions that have poor uptake. PMID:25363481

McKnight, Jacob; Holt, Douglas B

2014-12-01

37

A clinical and pharmacokinetic study of the combination of etravirine plus raltegravir in HIV patients with expanded intolerance or resistance  

PubMed Central

Introduction The combination of etravirine (ETR) plus raltegravir (RAL) could be an option for HIV patients with resistance, intolerance or important interactions with other drugs. However, there are few data on the efficacy, safety and pharmacokinetics of this dual therapy, taking into account the effect of HCV co-infection or the possible induction of ETR in the drug metabolism of RAL. Material and Methods Cohort study of HIV patients initiating ETR plus RAL as dual therapy. Plasma trough levels of RAL were measured by LC/MS after at least one month on therapy. Results A total of 25 patients have been included in this combination since 2009. Mean age was 46 years, 72% were male, and 20 patients (80%) had HCV co-infection (seven patients with fibrosis 3–4). Median nadir CD4+ count was 109 (60–209), and 21 patients had an HIV RNA level below 50 copies/mL. Median time on previous therapy was 473 months (IQR, 395–570), and reasons for this dual therapy was toxicity/intolerance in 19, and interactions in nine (two chemotherapy, three DAAs, two methadone, two other). After a median follow up of 722 days (473–1088: 53.3 patients-year), there were no cases of blips or virological failure. Six patients (24%) discontinued therapy after more than 1.5 year on therapy, in four cases due to lost follow up and in two due to simplification after finishing the reason for interaction. There were no cases of liver toxicity, and only two patients increased slightly transaminases values (grade 1 and 2). Total cholesterol and triglycerides levels decrease significantly after initiation (TC, from 182 to 165 at one year; p=0.01; TG from 185 to 143 mg/dL; p=0.01). CT/HDL ratio decreases from 4.35 to 4.28 after six months. Geometric mean plasma trough level of RAL was 166 ng/mL (IQR, 40–249) and only one patient (6%) was below the in vitro IC50 of the wild type. Conclusions The combination of ETR plus RAL as dual therapy is effective and safe in patients with expanded intolerance or interactions. There are no significant pharmacokinetic interactions between both drugs. PMID:25397548

Bañón, Sara; Moreno, Ana; Quereda, Carmen; Gomez, Cristina; Diaz de Santiago, Alberto; Perez-Elías, María J; Moreno, Santiago; Luis Casado, Jose

2014-01-01

38

Hubble Space Telescope Imaging of the Expanding Nebular Remnant of the 2006 Outburst of RS Ophiuchi  

E-print Network

We report {\\it Hubble Space Telescope} imaging obtained 155 days and 449 days after the 2006 outburst of RS Ophiuchi. Both epochs show evidence of extended emission, consistent with that seen in earlier radio observations, and a maximum expansion rate of $3200\\pm300$ km s$^{-1}$ (in the plane of the sky). The extended structure is consistent with the remnant having a bipolar morphology with an inclination similar to that determined for the binary.

D. J. Harman; M. F. Bode; M. J. Darnley; T. J. O'Brien; H. E. Bond; S. Starrfield; A. Evans; S. P. S. Eyres; V. A. R. M. Ribeiro; J. M. Echevarria

2008-09-26

39

Expanding the clinical phenotype of patients with a ZDHHC9 mutation.  

PubMed

In 2007, 250 families with X-linked intellectual disability (XLID) were screened for mutations in genes on the X-chromosome, and in 4 of these families, mutations in the ZDHHC9 gene were identified. The ID was either isolated or associated with a marfanoid habitus. ZDHHC9 encodes a palmitoyl transferase that catalyzes the posttranslational modification of NRAS and HRAS. Since this first description, no additional patient with a ZDHHC9 mutation has been reported in the literature. Here, we describe a large family in which we identified a novel pathogenic ZDHHC9 nonsense mutation (p.Arg298*) by parallel sequencing of all X-chromosome exons. The mutation cosegregated with the clinical phenotype in this family. An 18-year-old patient and his 40-year-old maternal uncle were evaluated. Clinical examination showed normal growth parameters, lingual fasciculation, limited extension of the elbows and metacarpophalangeal joints, and acrocyanosis. There was neither facial dysmorphism nor marfanoid habitus. Brain MRI detected a dysplastic corpus callosum. Neuropsychological testing showed mild intellectual disability. They both displayed generalized anxiety disorder, and the younger patient also suffered from significant behavior impairment that required attention or treatment. Speech evaluation detected satisfactory spoken language since both were able to provide information and to understand conversations of everyday life. Occupational therapy examination showed impaired visual-spatial and visual-motor performance with poor drawing/graphic skills. These manifestations are not specific enough to guide ZDHHC9 screening in patients with ID, and emphasize the value of next generation sequencing for making a molecular diagnosis and genetic counseling in families with XLID. PMID:24357419

Masurel-Paulet, Alice; Kalscheuer, Vera M; Lebrun, Nicolas; Hu, Hao; Levy, Fabienne; Thauvin-Robinet, Christel; Darmency-Stamboul, Véronique; El Chehadeh, Salima; Thevenon, Julien; Chancenotte, Sophie; Ruffier-Bourdet, Marie; Bonnet, Marlène; Pinoit, Jean-Michel; Huet, Frédéric; Desportes, Vincent; Chelly, Jamel; Faivre, Laurence

2014-03-01

40

The expanded Global Registry of Acute Coronary Events: Baseline characteristics, management practices, and hospital outcomes of patients with acute coronary syndromes  

Microsoft Academic Search

BACKGROUND: The Global Registry of Acute Coronary Events (GRACE)-a prospective, multinational study of patients hospitalized with acute coronary syndromes (ACSs)-was designed to improve the quality of care for patients with an ACS. Expanded GRACE aims to test the feasibility of a simplified data collection tool and provision of quarterly feedback to index individual hospital management practices to an international reference

Shaun G. Goodman; Wei Huang; Andrew T. Yan; Andrzej Budaj; Brian M. Kennelly; Joel M. Gore; Keith A. A. Fox; Robert J. Goldberg; Frederick A. Anderson Jr

2009-01-01

41

Geodetic Imaging: Expanding the Boundaries of Geodesy in the 21st Century  

NASA Astrophysics Data System (ADS)

High resolution (sub-meter) geodetic images covering tens to thousands of square kilometers have extended the boundaries of geodesy into related areas of the earth sciences, such as geomorphology and geodynamics, during the past decade, to archaeological exploration and site mapping during the past few years, and are now poised to transform studies of flora and fauna in the more remote regions of the world. Geodetic images produced from airborne laser scanning (ALS), a.k.a. airborne light detection and ranging (LiDAR) have proven transformative to the modern practice of geomorphology where researchers have used decimeter resolution digital elevation models (DEMs) to determine the spatial frequencies of evenly spaced features in terrain, and developed models and mathematical equations to explain how the terrain evolved to its present state and how it is expected to change in the future (Perron et al., 2009). In geodynamics researchers have used ';before' and ';after' geodetic images of the terrain near earthquakes, such as the 2010 El Mayor-Cucapah Earthquake, to quantify surface displacements and suggest models to explain the observed deformations (Oskin et. al., 2012). In archaeology, the ability of ALS to produce ';bare earth' DEMs of terrain covered with dense vegetation, including even tropical rain forests, has revolutionized the study of archaeology in highly forested areas, finding ancient structures and human modifications of landscapes not discovered by archaeologists working at sites for decades (Chase et al., 2011 & Evans et al., 2013), and finding previously unknown ruins in areas that ground exploration has not been able to penetrate since the arrival of the conquistadors in the new world in the 17th century (Carter et al., 2012). The improved spatial resolution and ability of the third generation ALS units to obtain high resolution bare earth DEMs and canopy models in areas covered in dense forests, brush, and even shallow water (steams, lakes, and coastal waters) is just beginning to attract the attention of researchers studying such plant life as marsh vegetation and sea grasses, and the habitats of animals as diverse as fish, migratory birds, and lions (Vierling et al., 2008). From thousands and thousands of survey markers covering large regions of the earth common to geodesy a half century ago, the focus of some geodesist has changed to billions and billions of points covering landscapes, which are enabling them to redefine and extend the limits of geodesy in the 21st century. References: Carter, W. E. et al., (2012), 'Geodetic Imaging: A New Tool for Mesoamerican Archaeology,' Eos, Trans. American Geophysical Union, Vol. 93, No. 42, pages 413-415. Chase, A. F. et al., (2010) 'Airborne LiDAR, archaeology, and the ancient Maya landscape at Caracol, Belize,' Journal Of Archaeological Science, vol. 38, no. 2, p. 387-398. Evans, D. H. et al., (2013), 'Uncovering archaeological landscapes at Angkor using lidar.' PNAS. Oskin, M. E. et al., (2012), 'Near-Field Deformation from the El Mayor-Cucapah Earthquake Revealed by Differential LIDAR,' Science. Vol. 335 no.6069, pp. 702-705. Perron, J. Taylor, et al (2009), 'Formation of evenly spaced ridges and valleys,' Nature, Vol. 460/23. Vierling, K. T. et al., (2008),'Lidar: shedding new light on habitat characterization and modeling,' Front Ecol Environ 2008, 6(2): 90-98.

Fernandez Diaz, J. C.; Carter, W. E.; Shrestha, R. L.; Glennie, C. L.

2013-12-01

42

Patient-centered medical home initiatives expanded in 2009-13: providers, patients, and payment incentives increased.  

PubMed

Patient-centered medical home initiatives are central to many efforts to reform the US health care delivery system. To better understand the extent and nature of these initiatives, in 2013 we performed a nationwide cross-sectional survey of initiatives that included payment reform incentives in their models, and we compared the results to those of a similar survey we conducted in 2009. We found that the number of initiatives featuring payment reform incentives had increased from 26 in 2009 to 114 in 2013. The number of patients covered by these initiatives had increased from nearly five million to almost twenty-one million. We also found that the proportion of time-limited initiatives--those with a planned end date--was 20 percent in 2013, a decrease from 77 percent in 2009. Finally, we found that the dominant payment model for patient-centered medical homes remained fee-for-service payments augmented by per member per month payments and pay-for-performance bonuses. However, those payments and bonuses were higher in 2013 than they were in 2009, and the use of shared-savings models was greater. The patient-centered medical home model is likely to continue both to become more common and to play an important role in delivery system reform. PMID:25288429

Edwards, Samuel T; Bitton, Asaf; Hong, Johan; Landon, Bruce E

2014-10-01

43

The Self-Expanding Symetis Acurate Does Not Increase Cerebral Microembolic Load When Compared to the Balloon-Expandable Edwards Sapien Prosthesis: A Transcranial Doppler Study in Patients Undergoing Transapical Aortic Valve Implantation  

PubMed Central

Objectives The aim of this study was to quantify potential differences in count, frequency and pattern of high-intensity transient signals (HITS) during transapical transcatheter aortic valve implantation (TA-TAVI), by comparing the Symetis Acurate TA (SA) with the balloon-expandable Edwards Sapien XT (ES) system. Background Recently, the Symetis Acurate TA revalving system has been introduced for TA-TAVI. The Symetis Acurate TA aortic bioprosthesis is self-expanding and is deployed by a specific two-step implantation technique. Whether this novel method increases the load of intraprocedural emboli, detected by transcranial Doppler ultrasound (TCD) as HITS, or not is not clear. Methods Twenty-two patients (n?=?11 in each study arm, median logistic EuroScore 20%, median STS score 7%) displayed continuous TCD signals of good quality throughout the entire TA-TAVI procedure and were included in the final analysis. Data are presented as median with interquartile ranges. Results No significant differences were detected in total procedural or interval-related HITS load (SA: 303 [200; 594], ES: 499 [285; 941]; p?=?0.16). With both devices, HITS peaked during prosthesis deployment (PD), whereas significantly fewer HITS occurred during instrumentation (SA: p?=?0.002; ES: <0.001) or post-implantation PI (SA: p?=?0.007; ES: <0.001). PD-associated HITS amounted to almost half of the total HITS load. One patient suffered new disabling stroke at 30 days. Thirty-day mortality amounted to 13.6% (3 of 22 patients). Conclusions Simplified transapical delivery using the self-expanding SA device does not increase HITS, despite of a two-step deployment technique with more interactions with the native aortic valve, when compared to the balloon-expandable ES valve. The similarity in HITS count, frequency and pattern with the two systems suggests a common mechanism for the release of cerebral microemboli. PMID:25289688

Erdoes, Gabor; Huber, Christoph; Basciani, Reto; Stortecky, Stefan; Windecker, Stephan; Wenaweser, Peter; Carrel, Thierry; Eberle, Balthasar

2014-01-01

44

Comparison of an expanded ataxia interactome with patient medical records reveals a relationship between macular degeneration and ataxia  

PubMed Central

Spinocerebellar ataxias 6 and 7 (SCA6 and SCA7) are neurodegenerative disorders caused by expansion of CAG repeats encoding polyglutamine (polyQ) tracts in CACNA1A, the alpha1A subunit of the P/Q-type calcium channel, and ataxin-7 (ATXN7), a component of a chromatin-remodeling complex, respectively. We hypothesized that finding new protein partners for ATXN7 and CACNA1A would provide insight into the biology of their respective diseases and their relationship to other ataxia-causing proteins. We identified 118 protein interactions for CACNA1A and ATXN7 linking them to other ataxia-causing proteins and the ataxia network. To begin to understand the biological relevance of these protein interactions within the ataxia network, we used OMIM to identify diseases associated with the expanded ataxia network. We then used Medicare patient records to determine if any of these diseases co-occur with hereditary ataxia. We found that patients with ataxia are at 3.03-fold greater risk of these diseases than Medicare patients overall. One of the diseases comorbid with ataxia is macular degeneration (MD). The ataxia network is significantly (P= 7.37 × 10?5) enriched for proteins that interact with known MD-causing proteins, forming a MD subnetwork. We found that at least two of the proteins in the MD subnetwork have altered expression in the retina of Ataxin-7266Q/+ mice suggesting an in vivo functional relationship with ATXN7. Together these data reveal novel protein interactions and suggest potential pathways that can contribute to the pathophysiology of ataxia, MD, and diseases comorbid with ataxia. PMID:21078624

Kahle, Juliette J.; Gulbahce, Natali; Shaw, Chad A.; Lim, Janghoo; Hill, David E.; Barabási, Albert-László; Zoghbi, Huda Y.

2011-01-01

45

Small Bowel Imaging in Managing Crohn's Disease Patients  

PubMed Central

The small bowel is essential to sustain alimentation and small bowel Crohn's disease (CD) may severely limit its function. Small bowel imaging is a crucial element in diagnosing small bowel CD, and treatment control with imaging is increasingly used to optimize the patients outcome. Thereby, capsule endoscopy, Balloon-assisted enteroscopy, and Magnetic resonance imaging have become key players to manage CD patients. In this review, role of small bowel imaging is detailed discussed for use in diagnosing and managing Crohn's disease patients. PMID:22474438

Albert, Jörg G.

2012-01-01

46

Preprocedural Imaging for Patients with Atrial Fibrillation and Heart Failure  

PubMed Central

Various electrophysiological procedures and device implantation has been shown to improve morbidity and mortality in patients with atrial fibrillation (AF) and patients with heart failure (HF). Non-invasive cardiac imaging is used extensively in the pre-procedural patient selection and for procedural guidance. In this review, we will discuss the application of pre-procedural cardiac imaging in patients with AF prior to pulmonary vein and left atrial ablation as well as insertion of left atrial occluder device. We also discuss the role of non-invasive cardiac imaging in the selection of appropriate HF patients for device therapy as well as their use in guiding implantation of biventricular pacemaker for cardiac resynchronization therapy by assessing left ventricular ejection fraction, coronary venous anatomy, mechanical dyssynchrony and myocardial scar. We describe new research associated with pre-procedural imaging in these patient cohorts. PMID:22828754

Thai, Wai-ee; Wai, Bryan; Truong, Quynh A.

2012-01-01

47

Magnetic source imaging supports clinical decision making in glioma patients  

Microsoft Academic Search

Objective: This study addresses the potential utility of preoperative functional imaging with magnetoencephalography (MEG) for the selection of glioma patients who are likely to benefit from resective surgical treatment regarding postoperative morbidity. Methods: One hundred and nineteen patients with gliomas adjacent to sensorimotor, visual and speech related brain areas were investigated preoperatively with a MAGNES II biomagnetometer. In each patient

O. Ganslandt; M. Buchfelder; P. Hastreiter; P. Grummich; R. Fahlbusch; C. Nimsky

2004-01-01

48

MR imaging in the management of patients with breast cancer.  

PubMed

Magnetic resonance (MR) imaging has high sensitivity in detecting and determining the extent of breast cancer and the information provided by this modality has proven valuable in patient management. Investigations defining the strengths of MR imaging, technical advances, and greater standardization of protocols have led to its increased use in patients with breast cancer, both before and following treatment. This article reviews techniques and procedures used in the performance and interpretation of breast MR examinations. Applications of MR imaging in the management of patients with breast cancer are also summarized, including preoperative evaluation of extent of disease, postoperative assessment of residual disease, and the detection of recurrent carcinoma. The use of MR imaging to evaluate patient response to chemotherapy and to assess patients with axillary lymph node metastases with an unknown primary lesion will also be discussed. PMID:16916000

Newstead, Gillian Maclaine

2006-08-01

49

Expanding Universe  

Microsoft Academic Search

A universe that expands with time. Although the possibility had been raised earlier through theoretical work carried out by Willem de Sitter (1872-1934), Aleksandr Friedmann (1888-1925), and the Abbé Georges Lemaître (1894-1966), that our universe is expanding was first demonstrated observationally in 1929 by Edwin P Hubble (1889-1953), through his measurements of the redshifts in the spectra of ...

P. Murdin

2000-01-01

50

Coma Patient Monitoring System Using Image Processing  

NASA Astrophysics Data System (ADS)

COMA PATIENT MONITORING SYSTEM provides high quality healthcare services in the near future. To provide more convenient and comprehensive medical monitoring in big hospitals since it is tough job for medical personnel to monitor each patient for 24 hours.. The latest development in patient monitoring system can be used in Intensive Care Unit (ICU), Critical Care Unit (CCU), and Emergency Rooms of hospital. During treatment, the patient monitor is continuously monitoring the coma patient to transmit the important information. Also in the emergency cases, doctor are able to monitor patient condition efficiently to reduce time consumption, thus it provides more effective healthcare system. So due to importance of patient monitoring system, the continuous monitoring of the coma patient can be simplified. This paper investigates about the effects seen in the patient using "Coma Patient Monitoring System" which is a very advanced product related to physical changes in body movement of the patient and gives Warning in form of alarm and display on the LCD in less than one second time. It also passes a sms to a person sitting at the distant place if there exists any movement in any body part of the patient. The model for the system uses Keil software for the software implementation of the developed system.

Sankalp, Meenu

2011-12-01

51

Imaging of orbital disorders in pediatric patients  

Microsoft Academic Search

.  \\u000a The spectrum of orbital lesions occurring in childhood is wide, including a variety of both benign and malignant disorders.\\u000a Although physical examination and fundoscopy may aid in establishing the diagnosis of retro-ocular lesions, imaging remains\\u000a a critical step in the evaluation of the pediatric orbit. Ultrasonography, CT, and MR imaging are the primary modalities for\\u000a the evaluation of the

Luis Gorospe; Aránzazu Royo; Teresa Berrocal; Pilar García-Raya; Pilar Moreno; José Abelairas

2003-01-01

52

Body Image Screening for Cancer Patients Undergoing Reconstructive Surgery  

PubMed Central

Objectives Body image is a critical issue for cancer patients undergoing reconstructive surgery, as they can experience disfigurement and functional impairment. Distress related to appearance changes can lead to various psychosocial difficulties, and patients are often reluctant to discuss these issues with their healthcare team. Our goals were to design and evaluate a screening tool to aid providers in identifying patients who may benefit from referral for specialized psychosocial care to treat body image concerns. Methods We designed a brief 4-item instrument and administered it at a single time point to cancer patients who were undergoing reconstructive treatment. We used simple and multinomial regression models to evaluate whether survey responses, demographic, or clinical variables predicted interest and enrollment in counseling. Results Over 95% of the sample (n = 248) endorsed some concerns, preoccupation, or avoidance due to appearance changes. Approximately one-third of patients were interested in obtaining counseling or additional information to assist with body image distress. Each survey item significantly predicted interest and enrollment in counseling. Concern about future appearance changes was the single best predictor of counseling enrollment. Sex, age, and cancer type were not predictive of counseling interest or enrollment. Conclusions We present initial data supporting use of the Body Image Screener for Cancer Reconstruction. Our findings suggest benefits of administering this tool to patients presenting for reconstructive surgery. It is argued that screening and treatment for body image distress should be provided to this patient population at the earliest possible time point. PMID:25066586

Fingeret, Michelle Cororve; Nipomnick, Summer; Guindani, Michele; Baumann, Donald; Hanasono, Matthew; Crosby, Melissa

2014-01-01

53

Accurate setup of paraspinal patients using a noninvasive patient immobilization cradle and portal imaging  

SciTech Connect

Because of the proximity of the spinal cord, effective radiotherapy of paraspinal tumors to high doses requires highly conformal dose distributions, accurate patient setup, setup verification, and patient immobilization. An immobilization cradle has been designed to facilitate the rapid setup and radiation treatment of patients with paraspinal disease. For all treatments, patients were set up to within 2.5 mm of the design using an amorphous silicon portal imager. Setup reproducibility of the target using the cradle and associated clinical procedures was assessed by measuring the setup error prior to any correction. From 350 anterior/posterior images, and 303 lateral images, the standard deviations, as determined by the imaging procedure, were 1.3 m, 1.6 m, and 2.1 in the ant/post, right/left, and superior/inferior directions. Immobilization was assessed by measuring patient shifts between localization images taken before and after treatment. From 67 ant/post image pairs and 49 lateral image pairs, the standard deviations were found to be less than 1 mm in all directions. Careful patient positioning and immobilization has enabled us to develop a successful clinical program of high dose, conformal radiotherapy of paraspinal disease using a conventional Linac equipped with dynamic multileaf collimation and an amorphous silicon portal imager.

Lovelock, D. Michael; Hua Chiaho; Wang Ping; Hunt, Margie; Fournier-Bidoz, Nathalie; Yenice, Kamil; Toner, Sean; Lutz, Wendell; Amols, Howard; Bilsky, Mark; Fuks, Zvi; Yamada, Yoshiya [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York, 10021 (United States); Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, New York, New York 10021 (United States); Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021 (United States)

2005-08-15

54

Zirconium-89 Labeled Antibodies: A New Tool for Molecular Imaging in Cancer Patients  

PubMed Central

Antibody based positron emission tomography (immuno-PET) imaging is of increasing importance to visualize and characterize tumor lesions. Additionally, it can be used to identify patients who may benefit from a particular therapy and monitor the therapy outcome. In recent years the field is focused on 89Zr, a radiometal with near ideal physical and chemical properties for immuno-PET. In this review we will discuss the production of??89Zr, the bioconjugation strategies, and applications in (pre-)clinical studies of??89Zr-based immuno-PET in oncology. To date, 89Zr-based PET imaging has been investigated in a wide variety of cancer-related targets. Moreover, clinical studies have shown the feasibility for 89Zr-based immuno-PET to predict and monitor treatment, which could be used to tailor treatment for the individual patient. Further research should be directed towards the development of standardized and robust conjugation methods and improved chelators to minimize the amount of released Zr4+ from the antibodies. Additionally, further validation of the imaging method is required. The ongoing development of new 89Zr-labeled antibodies directed against novel tumor targets is expected to expand applications of??89Zr-labeled immuno-PET to a valuable method in the medical imaging. PMID:24991539

van de Watering, Floor C. J.; Rijpkema, Mark; Perk, Lars; Brinkmann, Ulrich; Oyen, Wim J. G.; Boerman, Otto C.

2014-01-01

55

Are tactile acuity and clinical symptoms related to differences in perceived body image in patients with chronic nonspecific lower back pain?  

PubMed

Clinically, perceived image of the lower back and the two-point discrimination (TPD) test are used as markers for evaluating alterations of cortical reorganization. The purpose of the present study was to examine whether TPD and selected clinical findings are different in subgroups of individuals with chronic nonspecific lower back pain (CNLBP) based on body image drawings. Forty-two patients with CNLBP and seventeen healthy individuals were recruited. Perceived body image, TPD and clinical profiles was measured. Of the patients with CNLBP, 42.8% had a normal perceived body image, 28.5% an expanded image, and 28.5% a shrunken image. The TPD distance threshold was significantly larger for the expanded subgroup (13.3 ± 6.8 mm) compared with the control (5.5 ± 3.8 mm; Difference, 7.8; 95%CI, 1.83 to 13.66; p < 0.05) and normal subgroups (4.5 ± 5.5 mm; Difference, 8.8; 95%CI, 2.90 to 14.59; p < 0.05). No significant differences in pain intensity, duration of pain, Roland Morris Disability Questionnaire (RDQ), and Pain Catastrophizing Scale (PCS) scores were found between three body image subgroups. Our results suggest that TPD is increased in patients who report an expanded perceived image of the lower back compared with healthy individuals and patients who report a normal image. The effectiveness of new rehabilitation techniques may be evaluated by assessing perceived image of the lower back and TPD values for patients with CNLBP before and after treatment. PMID:25081221

Nishigami, Tomohiko; Mibu, Akira; Osumi, Michihiro; Son, Kouki; Yamamoto, Shyogo; Kajiwara, Saori; Tanaka, Katsuyoshi; Matsuya, Ayako; Tanabe, Akihito

2015-02-01

56

Cotransplantation of HLA-Identical Sibling Culture-Expanded Mesenchymal Stem Cells and Hematopoietic Stem Cells in Hematologic Malignancy Patients  

Microsoft Academic Search

Mesenchymal stem cells (MSCs) are found in a variety of tissues, including human bone marrow; secrete hematopoietic cytokines; support hematopoietic progenitors in vitro; and possess potent immunosuppressive properties. We hypothesized that cotransplantation of culture-expanded MSCs and hematopoietic stem cells (HSCs) from HLA-identical sibling donors after myeloablative therapy could facilitate engraftment and lessen graft-versus-host disease (GVHD); however, the safety and feasibility

Hillard M. Lazarus; Omer N. Koc; Steven M. Devine; Peter Curtin; Richard T. Maziarz; H. Kent Holland; Elizabeth J. Shpall; Philip McCarthy; Kerry Atkinson; Brenda W. Cooper; Stanton L. Gerson; Mary J. Laughlin; Fausto R. Loberiza; Annemarie B. Moseley; Andrea Bacigalupo

2005-01-01

57

The Value of Perioperative Imaging in Patients with Uterine Sarcomas  

PubMed Central

Objective To explore the yield and impact of perioperative imaging on management among patients undergoing surgical resection and treatment of uterine sarcomas. Methods A retrospective chart review was done for women with histologically confirmed uterine sarcomas treated at Barnes Jewish Hospital/Washington University from 2001–2007. Descriptive statistics, Cox multivariate models, and Kaplan-Meier plots were used to evaluate associations and survival. Results A total of 92 patients were identified and 55(60%) were diagnosed with stage III–IV disease. Perioperative imaging was obtained in 84 (91%) cases, including chest x-ray in 66 (72%), computerized tomography (CT) of the abdomen and pelvis in 59 (64%), chest CT in 33 (36%), positron emission tomography (PET) in 8 (9%), and CT of the head, pelvic magnetic resonance imaging (MRI), or bone scan in a total of 2 (2.2%). Imaging identified abnormalities concerning for metastases in 30 (32%) studies. Thirty-four recurrences have been documented, and 21 (62%) of these treatment failures were extrapelvic. Multivariate analysis of this series noted that tomographic evidence of extrauterine disease predicted recurrence (p=0.028) and incomplete surgical resection (p=0.003, HR 6.0 95% CI 1.9–19.9) predicted disease free survival. Imaging contributed to change in surgical and postsurgical treatment decisions in 8 (9%) patients. Conclusion Pretreatment imaging studies change management in a minority of patients with newly diagnosed uterine sarcomas. PMID:19577795

Nugent, Elizabeth K; Zighelboim, Israel; Case, Ashley S; Gao, Feng; Thaker, Premal H; Rader, Janet S; Mutch, David G; Massad, L Stewart

2015-01-01

58

Clinical and imaging heterogeneity of polymicrogyria: a study of 328 patients  

PubMed Central

Polymicrogyria is one of the most common malformations of cortical development and is associated with a variety of clinical sequelae including epilepsy, intellectual disability, motor dysfunction and speech disturbance. It has heterogeneous clinical manifestations and imaging patterns, yet large cohort data defining the clinical and imaging spectrum and the relative frequencies of each subtype are lacking. The aims of this study were to determine the types and relative frequencies of different polymicrogyria patterns, define the spectrum of their clinical and imaging features and assess for clinical/imaging correlations. We studied the imaging features of 328 patients referred from six centres, with detailed clinical data available for 183 patients. The ascertainment base was wide, including referral from paediatricians, geneticists and neurologists. The main patterns of polymicrogyria were perisylvian (61%), generalized (13%), frontal (5%) and parasagittal parieto-occipital (3%), and in 11% there was associated periventricular grey matter heterotopia. Each of the above patterns was further divided into subtypes based on distinguishing imaging characteristics. The remaining 7% were comprised of a number of rare patterns, many not described previously. The most common clinical sequelae were epileptic seizures (78%), global developmental delay (70%), spasticity (51%) and microcephaly (50%). Many patients presented with neurological or developmental abnormalities prior to the onset of epilepsy. Patients with more extensive patterns of polymicrogyria presented at an earlier age and with more severe sequelae than those with restricted or unilateral forms. The median age at presentation for the entire cohort was 4 months with 38% presenting in either the antenatal or neonatal periods. There were no significant differences between the prevalence of epilepsy for each polymicrogyria pattern, however patients with generalized and bilateral forms had a lower age at seizure onset. There was significant skewing towards males with a ratio of 3:2. This study expands our understanding of the spectrum of clinical and imaging features of polymicrogyria. Progression from describing imaging patterns to defining anatomoclinical syndromes will improve the accuracy of prognostic counselling and will aid identification of the aetiologies of polymicrogyria, including genetic causes. PMID:20403963

Jansen, Anna; Pilz, Daniela T.; Stoodley, Neil; Marini, Carla; Dubeau, Francois; Malone, Jodie; Mitchell, L. Anne; Mandelstam, Simone; Scheffer, Ingrid E.; Berkovic, Samuel F.; Andermann, Frederick; Andermann, Eva; Guerrini, Renzo; Dobyns, William B.

2010-01-01

59

Expanding the clinical spectrum of the 16p11.2 chromosomal rearrangements: three patients with syringomyelia  

PubMed Central

16p11.2 rearrangements are associated with developmental delay, cognitive impairment, autism spectrum disorder, behavioral problems (especially attention-deficit hyperactivity disorder), seizures, obesity, dysmorphic features, and abnormal head size. In addition, congenital anomalies and abnormal brain findings were frequently observed in patients with these rearrangements. We identified and performed a detailed microarray, phenotypic, and radiological characterization of three new patients with 16p11.2 rearrangements: two deletion patients and one patient with the reciprocal duplication. All patients have a heterozygous loss (deletion) or gain (duplication) corresponding to chromosomal coordinates (chr16: 29?528?190–30?107?184) with a minimal size of 579?kb. The deletion patients had language delay and learning disabilities and one met criteria for pervasive developmental disorder not otherwise specified. The duplication patient received a diagnosis of autism and had academic deficits and behavioral problems. The patients with deletion had long cervicothoracic syringomyelia and the duplication patient had long thoracolumbar syringomyelia. The syringomyelia in one patient with deletion was associated with Chiari malformation. Our findings highlight the broad spectrum of clinical and neurological manifestations in patients with 16p11.2 rearrangements. Our observation suggests that genes (or a single gene) within the implicated interval have significant roles in the pathogenesis of syringomyelia. A more comprehensive and systematic research is warranted to study the frequency and spectrum of malformations in the central nervous system in these patients. PMID:20959866

Schaaf, Christian P; Goin-Kochel, Robin P; Nowell, Kerri P; Hunter, Jill V; Aleck, Kirk A; Cox, Sarah; Patel, Ankita; Bacino, Carlos A; Shinawi, Marwan

2011-01-01

60

[Typical patient radiation doses in diagnostic imaging].  

PubMed

Radiologists should be able to appreciate the radiation dose delivered to patients for routine diagnostic procedures. The radiology report should include data necessary to calculate the patient dose in Gray. Using the effective dose, it is possible to compare with other source of radiation exposure. Simple formulas, taking into account different anatomical regions, derived from dose-area product (conventional radiography) or dose-length product (CT) are provided to calculate the effective dose in Sievert. For conventional (non-interventional) radiography, the effective dose for a given exam is inferior or equal to the yearly background radiation. For CT, the effective dose corresponds to 1 to 10 years of yearly background radiation. PMID:21178891

Chateil, J-F; Aubert, B; Brisse, H

2010-11-01

61

Nuclear Medicine Imaging in the Pediatric Patient  

PubMed Central

Pediatric nuclear medicine provides a wealth of information on a variety of disease states; however, precautions on dosing have to be taken into consideration. Also, expertise in conducting procedures and interpreting the results in pediatric patients is necessary. Emphasis is placed on diagnostic studies involving the central nervous system, musculoskeletal system, genitourinary system, gastrointestinal system, endocrine system, pulmonary system, and cardiovascular system along with a brief explanation of the mechanism of localization of the radiopharmaceuticals involved. Radiation safety issues are addressed when the expectant mother or nursing mother is administered radiopharmaceuticals. PMID:23115536

Loveless, Vivian

2006-01-01

62

HIGH-RESOLUTION EXPANDED VERY LARGE ARRAY IMAGE OF DIMETHYL ETHER (CH{sub 3}){sub 2}O IN ORION-KL  

SciTech Connect

We report the first subarcsecond (0.''65 x 0.''51) image of the dimethyl ether molecule, (CH{sub 3}){sub 2}O, toward the Orion Kleinmann-Low nebula. The observations were carried at 43.4 GHz with the Expanded Very Large Array (EVLA). The distribution of the lower energy transition 6{sub 1,5}-6{sub 0,6}, EE (E {sub u} = 21 K) mapped in this study is in excellent agreement with the published dimethyl ether emission maps imaged with a lower resolution. The main emission peaks are observed toward the Compact Ridge and Hot Core southwest components, at the northern parts of the Compact Ridge and in an intermediate position between the Compact Ridge and the Hot Core. A notable result is that the distribution of dimethyl ether is very similar to that of another important larger O-bearing species, the methyl formate (HCOOCH{sub 3}), imaged at a lower resolution. Our study shows that higher spectral resolution (WIDAR correlator) and increased spectral coverage provided by the EVLA offer new possibilities for imaging complex molecular species. The sensitivity improvement and the other EVLA improvements make this instrument well suited for high sensitivity, high angular resolution, and molecular line imaging.

Favre, C. [Department of Physics and Astronomy, University of Arhus, Ny Munkegade 120, DK-8000 Arhus C (Denmark); Wootten, H. A.; Remijan, A. J. [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475 (United States); Brouillet, N.; Despois, D.; Baudry, A. [Universite de Bordeaux, OASU, 2 rue de l'Observatoire, BP 89, 33271 Floirac Cedex (France); Wilson, T. L., E-mail: favre@phys.au.dk, E-mail: brouillet@obs.u-bordeaux1.fr, E-mail: despois@obs.u-bordeaux1.fr, E-mail: baudry@obs.u-bordeaux1.fr, E-mail: awootten@nrao.edu, E-mail: aremijan@nrao.edu, E-mail: tom.wilson@nrl.navy.mil [Naval Research Laboratory, Code 7210, Washington, DC 20375 (United States)

2011-09-20

63

Magnetic resonance imaging in patients with congenital heart disease.  

PubMed

Magnetic resonance imaging (MRI) was conducted with use of the spin-echo technique (0.35 Tesla) in 22 patients with a variety of congenital and cardiovascular anomalies and in 16 normal volunteers. Electrocardiographic (ECG) synchronization of the data acquisition produced transverse, parasagittal, and coronal tomograms that were used to define size and relationship of the great vessels and internal cardiac structures. MRI findings were corroborated by angiography and sector-scan echocardiography. In most patients the diagnosis had been established before the MRI study. MRI detected all of 11 abnormalities at the level of the great vessels, all of six atrial septal abnormalities, and 10 of 11 ventricular septal defects. Images of poor quality resulting from patient motion were obtained in the one instance in which a small ventricular septal defect was not imaged. Of two patients with Ebstein's anomaly, the displacement of the tricuspid leaflets was shown in one patient but was not evident in another. Complex anomalies such as double-outlet right ventricle, uncorrected L-transposition, single atrioventricular valve, single ventricle, and common ventricle were clearly shown by MRI. Initial experience with MRI has indicated the effectiveness of this technique for defining great vessel and internal cardiac anatomy in patients with congenital heart disease. This is accomplished without the use of contrast media and is thus a completely noninvasive technique for cardiovascular diagnosis. PMID:6488498

Higgins, C B; Byrd, B F; Farmer, D W; Osaki, L; Silverman, N H; Cheitlin, M D

1984-11-01

64

Patient positioning method based on binary image correlation between two edge images for proton-beam radiation therapy  

Microsoft Academic Search

A new technique based on normalized binary image correlation between two edge images has been proposed for positioning proton-beam radiotherapy patients. A Canny edge detector was used to extract two edge images from a reference x-ray image and a test x-ray image of a patient before positioning. While translating and rotating the edged test image, the absolute value of the

Akira Sawada; Kiyoshi Yoda; Masumi Numano; Yasuyuki Futami; Haruo Yamashita; Shigeyuki Murayama; Hironobu Tsugami

2005-01-01

65

Imaging of patients treated with bariatric surgery  

PubMed Central

Summary Over the past few years, obesity has become a major clinical and population concern in the majority of developed countries. Obesity leads to significant systemic disorders, such as hypertension, hypercholesterolemia, hypertriglyceridemia and insulin resistance, and also increases the risk of developing cardiovascular diseases (ischemic heart disease, ischemic stroke), metabolic diseases (type 2 diabetes), certain types of cancer, and degenerative bone disorders (osteoarthritis). Health hazards associated with epidemic of obesity and potential benefits of weight loss have spurred interest in new treatment methods. Bariatric surgical procedures constitute a recognized alternative in cases where conservative management of obesity fails. Several bariatric operations can be distinguished: restrictive procedures, such as adjustable gastric band (AGB) and vertical banded gastroplasty (VBG); predominantly malabsorptive procedures, such as biliopancreatic diversion (BPD), and a combination of both methods, such as Roux-en-Y gastric bypass. The adverse consequences of surgical treatment of obesity include i.a.: intestinal anastomotic leakage, impaired intestinal permeability and internal hernia, dilatation of the stomach, gastrointestinal anastomotic stenosis, marginal ulceration, incisional hernia. Basic knowledge of procedures in the surgical treatment of obesity is of vital importance for the radiologist during evaluation of upper gastrointestinal tract in the early and late postoperative period, allowing correct interpretation of acquired images as well as recognition of typical complications. PMID:24497896

Lemanowicz, Adam; Serafin, Zbigniew

2014-01-01

66

Diagnostic imaging in a patient with an acute knee injury.  

PubMed

The patient was a 23-year-old man, currently serving in a military airborne operations unit. During a jump training exercise, the patient's right lower extremity became entangled in his parachute equipment upon exiting the aircraft, which caused hyperextension and valgus forces upon his right knee. Due to concern for a fracture, the patient was transported to an emergency department, where conventional radiographs were completed and interpreted by a radiologist as negative for a fracture. Following further physical examination by a physical therapist, magnetic resonance imaging of the right knee was ordered, revealing ruptures of the anterior cruciate ligament and medial collateral ligament. PMID:23277192

Sago, Carrie E; Labuda, Craig S

2013-01-01

67

IR imaging of blood circulation of patients with vascular disease  

Microsoft Academic Search

We conducted a preliminary IR imaging study of blood circulation in patients with peripheral vascular diseases. Abnormal blood flow is common in older adults, especially those with elevated blood lipids, diabetes, hypertension, and a history of smoking. All of these conditions have a high prevalence in our population, often with more than one condition in the same individual. The differences

Hsin Wang; Dwight R. Wade Jr.; Jack Kam

2004-01-01

68

Septicemia in neutropenic patients infected with Clostridium tertium resistant to cefepime and other expanded-spectrum cephalosporins.  

PubMed

Clostridium tertium was isolated from two immunocompromised patients with septicemia, fever, and gastrointestinal symptoms. The strains were resistant to ceftazidime, cefepime, and clindamycin; intermediately resistant to penicillin; and susceptible to metronidazole, quinolones, and vancomycin. PMID:10523601

Steyaert, S; Peleman, R; Vaneechoutte, M; De Baere, T; Claeys, G; Verschraegen, G

1999-11-01

69

Stem cell treatment for patients with autoimmune disease by systemic infusion of culture-expanded autologous adipose tissue derived mesenchymal stem cells  

PubMed Central

Prolonged life expectancy, life style and environmental changes have caused a changing disease pattern in developed countries towards an increase of degenerative and autoimmune diseases. Stem cells have become a promising tool for their treatment by promoting tissue repair and protection from immune-attack associated damage. Patient-derived autologous stem cells present a safe option for this treatment since these will not induce immune rejection and thus multiple treatments are possible without any risk for allogenic sensitization, which may arise from allogenic stem cell transplantations. Here we report the outcome of treatments with culture expanded human adipose-derived mesenchymal stem cells (hAdMSCs) of 10 patients with autoimmune associated tissue damage and exhausted therapeutic options, including autoimmune hearing loss, multiple sclerosis, polymyotitis, atopic dermatitis and rheumatoid arthritis. For treatment, we developed a standardized culture-expansion protocol for hAdMSCs from minimal amounts of fat tissue, providing sufficient number of cells for repetitive injections. High expansion efficiencies were routinely achieved from autoimmune patients and from elderly donors without measurable loss in safety profile, genetic stability, vitality and differentiation potency, migration and homing characteristics. Although the conclusions that can be drawn from the compassionate use treatments in terms of therapeutic efficacy are only preliminary, the data provide convincing evidence for safety and therapeutic properties of systemically administered AdMSC in human patients with no other treatment options. The authors believe that ex-vivo-expanded autologous AdMSCs provide a promising alternative for treating autoimmune diseases. Further clinical studies are needed that take into account the results obtained from case studies as those presented here. PMID:22017805

2011-01-01

70

Can radiologic images be incorporated into the electronic patient record?  

PubMed

As radiology makes advances toward filmlessness, all of medicine is headed, just as rapidly, toward paperless transmission of patient information. While there are obvious advantages to this electronic approach, and several standards to conform to for the transmission of textual (Health Level 7 [HL-7]) and image (Digital Imaging and Communications in Medicine [DICOM]) data, it is the integration of these two data sets that is clinically essential and yet poorly defined. This report defines an approach for, and the successful implementation of, the integration of radiologic image data with textual data contained within the electronic patient record (EPR) through the use of standard internet protocols. Incorporation of medical images in the EPR has proven to be critical to the successful deployment of picture archiving and communications systems (PACS) and the reduction of film consumption at Massachusetts General Hospital (MGH). Since the installation of the first internet-based Image Data Repository (IDR) at MGH in 1995, the system has adequately served to meet the needs of clinical requests by both radiology-only browser users and users of the EPR. It has drastically reduced the need for film and provided concurrent display of images and text throughout the institution and beyond. PMID:10847383

Dreyer, K J; Mehta, A; Thrall, J

2000-05-01

71

Indium-111 leukocyte imaging in patients with rheumatoid arthritis  

SciTech Connect

This study evaluates the usefulness of labeled leukocyte imaging in patients with rheumatoid arthritis. In 33 patients, the incidence of pain and swelling in 66 wrist joints and 66 knee joints was compared with the accumulation of (/sup 111/In)leukocytes. No accumulation of (/sup 111/In)leukocytes was seen in any of the patients' wrists (0/12) or knee joints (0/14) when both pain and swelling were absent. In contrast, 93% (25/27) of wrist joints and 80% (24/30) of knee joints with both pain and swelling were positive by (/sup 111/In)leukocyte scintigraphy. There was little correlation between the stage of the disease, as determined by radiography, and (/sup 111/In)leukocyte accumulation. This study suggests that (/sup 111/In)leukocyte imaging may be a reliable procedure for monitoring the activity of rheumatoid arthritis, especially for confirming the lack of an ongoing inflammatory response.

Uno, K.; Matsui, N.; Nohira, K.; Suguro, T.; Kitakata, Y.; Uchiyama, G.; Miyoshi, T.; Uematsu, S.; Inoue, S.; Arimizu, N.

1986-03-01

72

Expanding multimodal microscopy by high spectral resolution coherent anti-Stokes Raman scattering imaging for clinical disease diagnostics.  

PubMed

Over the past years fast label-free nonlinear imaging modalities providing molecular contrast of endogenous disease markers with subcellular spatial resolution have been emerged. However, applications of these imaging modalities in clinical settings are still at the very beginning. This is because single nonlinear imaging modalities such as second-harmonic generation (SHG) and two-photon excited fluorescence (TPEF) have only limited value for diagnosing diseases due to the small number of endogenous markers. Coherent anti-Stokes Raman scattering (CARS) microscopy on the other hand can potentially be added to SHG and TPEF to visualize a much broader range of marker molecules. However, CARS requires a second synchronized laser source and the detection of a certain wavenumber range of the vibrational spectrum to differentiate multiple molecules, which results in increased experimental complexity and often inefficient excitation of SHG and TPEF signals. Here we report the application of a novel near-infrared (NIR) fiber laser of 1 MHz repetition rate, 65 ps pulse duration, and 1 cm(-1) spectral resolution to realize an efficient but experimentally simple SGH/TPEF/multiplex CARS multimodal imaging approach for a label-free characterization of composition of complex tissue samples. This is demonstrated for arterial tissue specimens demonstrating differentiation of elastic fibers, triglycerides, collagen, myelin, cellular cytoplasm, and lipid droplets by analyzing the CARS spectra within the C-H stretching region only. A novel image analysis approach for multispectral CARS data based on colocalization allows correlating spectrally distinct pixels to morphologic structures. Transfer of this highly precise but compact and simple to use imaging approach into clinical settings is expected in the near future. PMID:23781826

Meyer, Tobias; Chemnitz, Mario; Baumgartl, Martin; Gottschall, Thomas; Pascher, Torbjörn; Matthäus, Christian; Romeike, Bernd F M; Brehm, Bernhard R; Limpert, Jens; Tünnermann, Andreas; Schmitt, Michael; Dietzek, Benjamin; Popp, Jürgen

2013-07-16

73

Patient-centered imaging: shared decision making for cardiac imaging procedures with exposure to ionizing radiation.  

PubMed

The current paper details the recommendations arising from an NIH-NHLBI/NCI-sponsored symposium held in November 2012, aiming to identify key components of a radiation accountability framework fostering patient-centered imaging and shared decision-making in cardiac imaging. Symposium participants, working in 3 tracks, identified key components of a framework to target critical radiation safety issues for the patient, the laboratory, and the larger population of patients with known or suspected cardiovascular disease. The use of ionizing radiation during an imaging procedure should be disclosed to all patients by the ordering provider at the time of ordering, and reinforced by the performing provider team. An imaging protocol with effective dose ?3 mSv is considered very low risk, not warranting extensive discussion or written informed consent. However, a protocol effective dose >20 mSv was proposed as a level requiring particular attention in terms of shared decision-making and either formal discussion or written informed consent. Laboratory reporting of radiation dosimetry is a critical component of creating a quality laboratory fostering a patient-centered environment with transparent procedural methodology. Efforts should be directed to avoiding testing involving radiation, in patients with inappropriate indications. Standardized reporting and diagnostic reference levels for computed tomography and nuclear cardiology are important for the goal of public reporting of laboratory radiation dose levels in conjunction with diagnostic performance. The development of cardiac imaging technologies revolutionized cardiology practice by allowing routine, noninvasive assessment of myocardial perfusion and anatomy. It is now incumbent upon the imaging community to create an accountability framework to safely drive appropriate imaging utilization. PMID:24530677

Einstein, Andrew J; Berman, Daniel S; Min, James K; Hendel, Robert C; Gerber, Thomas C; Carr, J Jeffrey; Cerqueira, Manuel D; Cullom, S James; DeKemp, Robert; Dickert, Neal W; Dorbala, Sharmila; Fazel, Reza; Garcia, Ernest V; Gibbons, Raymond J; Halliburton, Sandra S; Hausleiter, Jörg; Heller, Gary V; Jerome, Scott; Lesser, John R; Raff, Gilbert L; Tilkemeier, Peter; Williams, Kim A; Shaw, Leslee J

2014-04-22

74

Initial Experiences of Young Cardiologists with Balloon-Expandable Transcatheter Aortic Valve Implantation in Turkey: A Case Series of Eleven Patients  

PubMed Central

Objective: Surgical aortic valve replacement is the gold standard of treatment for symptomatic severe aortic stenosis in all age groups. Transcatheter aortic valve implantation (TAVI), which is performed by senior interventional cardiologists in experienced centers, is an alternative therapy for patients considered to be at high risk for surgery. The aim of this study is to describe the procedural success and short-term results of TAVI performed by young interventional cardiologists in Trabzon, Turkey. Materials and Methods: Eleven patients, 10 women and 1 man, who were treated by balloon-expandable TAVI through transfemoral access between January 2012 and April 2012, were included in the study. The clinical and echocardiographic parameters of the patients were compared before and three months after the procedure. Results: The median calculated logistic EuroSCORE and Society of Thoracic Surgeons (STS) score of patients were 28% (24%–34%) and 14% (12%–18%), respectively. The median age of the patients was 83 years and ranged from 80–85 years. The mean aortic valve pressure gradient and the aortic valve area were significantly improved after TAVI. The mean aortic valve pressure gradient was 48 (46–53) mmHg before treatment and 20 (16–23) mmHg after treatment (p=0.003). The aortic valve area was 0.65 (0.55–0.70) cm2 before treatment and 1.7 (1.6–1.8) cm2 after treatment. The functional status of the patients improved from NYHA class 3–4 to NYHA class 1–2. Intraprocedural mortality was not observed, and the overall 3 month mortality was 9%. Conclusion: TAVI can be performed successfully by young cardiologists. In centers with high patient loads, we encourage young cardiologists to perform TAVI if they have received the appropriate training and to form specialized, cooperating teams with a focus on TAVI.

Gokdeniz, Tayyar; Aykan, Ahmet Cagri; Agac, Mustafa Tarik; Parlar, Ali Ihsan; Dogan, Orhan Veli; Celik, Sukru

2013-01-01

75

Depression in adults with congenital heart disease-public health challenge in a rapidly expanding new patient population  

PubMed Central

There is a growing population of adults with congenital heart disease (CHD) due to improved survival beyond childhood. It has been suggested that adults with CHD may be at increased risk for mental health problems, particularly depression. The reported incidence of depression in CHD varies from 9% to 30%. This review examines the evidence for a higher depression rate in CHD vs general population. Possible explanations are offered from a variety of disease models, ranging from brain injury to the psychoanalytical approach. Risk factors for an abnormal emotional adjustment and depression include early exposure to stress from illness and medical interventions in infancy, separation from the parents during hospitalizations and brain organic syndromes. Later in life, patients often have to cope with physical limitations. Recent improvements in care may be protective. Current patients may benefit from an earlier age at first surgical intervention, fewer reoperations and inclusion to the mainstream schooling, among other factors. At this point, there is little systematic knowledge about evidence-based therapeutic interventions for depression in adults with CHD. Health care providers of patients with CHD should be aware of mental health challenges and may take a more proactive approach to identifying patients at risk for depression. PMID:23802047

Pauliks, Linda B

2013-01-01

76

CASE REPORT Septicemia in Neutropenic Patients Infected with Clostridium tertium Resistant to Cefepime and Other Expanded-Spectrum Cephalosporins  

Microsoft Academic Search

Clostridium tertium was isolated from two immunocompromised patients with septicemia, fever, and gastro- intestinal symptoms. The strains were resistant to ceftazidime, cefepime, and clindamycin; intermediately resistant to penicillin; and susceptible to metronidazole, quinolones, and vancomycin. CASE REPORTS Case 1. A 65-year-old male was diagnosed with acute my- eloid leukemia and treated with chemotherapy. During neu- tropenia, he became febrile and

SOPHIA STEYAERT; RENAAT PELEMAN; MARIO VANEECHOUTTE; THIERRY DE BAERE; GEERT CLAEYS; GERDA VERSCHRAEGEN

1999-01-01

77

Expanding the horizons of histoplasmosis: disseminated histoplasmosis in a renal transplant patient after a trip to Bangladesh.  

PubMed

Histoplasmosis is recognized to occur in the Ohio and Mississippi River Valleys of the United States, but less widely appreciated is its worldwide distribution. We report a case of disseminated histoplasmosis with disease involving skin, lungs, and epiglottis in a renal transplant patient 6 months after a trip to Bangladesh, to highlight the potential risk of acquisition of this infection in the Indian subcontinent. PMID:19878490

Rappo, U; Beitler, J R; Faulhaber, J R; Firoz, B; Henning, J S; Thomas, K M; Maslow, M; Goldfarb, D S; Horowitz, H W

2010-04-01

78

Spectral CT imaging in patients with Budd-Chiari syndrome: investigation of image quality.  

PubMed

To assess the image quality of monochromatic imaging from spectral CT in patients with Budd-Chiari syndrome (BCS), fifty patients with BCS underwent spectral CT to generate conventional 140 kVp polychromatic images (group A) and monochromatic images, with energy levels from 40 to 80, 40 + 70, and 50 + 70 keV fusion images (group B) during the portal venous phase (PVP) and the hepatic venous phase (HVP). Two-sample t tests compared vessel-to-liver contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) for the portal vein (PV), hepatic vein (HV), inferior vena cava. Readers' subjective evaluations of the image quality were recorded. The highest SNR values in group B were distributed at 50 keV; the highest CNR values in group B were distributed at 40 keV. The higher CNR values and SNR values were obtained though PVP of PV (SNR 18.39 ± 6.13 vs. 10.56 ± 3.31, CNR 7.81 ± 3.40 vs. 3.58 ± 1.31) and HVP of HV (3.89 ± 2.08 vs. 1.27 ± 1.55) in the group B; the lower image noise for group B was at 70 keV and 50 + 70 keV (15.54 ± 8.39 vs. 18.40 ± 4.97, P = 0.0004 and 18.97 ± 7.61 vs. 18.40 ± 4.97, P = 0.0691); the results show that the 50 + 70 keV fusion image quality was better than that in group A. Monochromatic energy levels of 40-70, 40 + 70, and 50 + 70 keV fusion image can increase vascular contrast and that will be helpful for the diagnosis of BCS, we select the 50 + 70 keV fusion image to acquire the best BCS images. PMID:24833430

Su, Lei; Dong, Junqiang; Sun, Qiang; Liu, Jie; Lv, Peijie; Hu, Lili; Yan, Liangliang; Gao, Jianbo

2014-11-01

79

Using a patient image archive to diagnose retinopathy  

SciTech Connect

Diabetes has become an epidemic that is expected to impact 365 million people worldwide by 2025. Consequently, diabetic retinopathy is the leading cause of blindness in the industrialized world today. If detected early, treatments can preserve vision and significantly reduce debilitating blindness. Through this research we are developing and testing a method for automating the diagnosis of retinopathy in a screening environment using a patient archive and digital fundus imagery. We present an overview of our content-based image retrieval (CBIR) approach and provide performance results for a dataset of 98 images from a study in Canada when compared to an archive of 1,355 patients from a study in the Netherlands. An aggregate performance of 89% correct diagnosis is achieved, demonstrating the potential of automated, web-based diagnosis for a broad range of imagery collected under different conditions and with different cameras.

Tobin Jr, Kenneth William [ORNL; Abramoff, M.D. [University of Iowa; Chaum, Edward [University of Tennessee, Knoxville (UTK); Giancardo, Luca [ORNL; Govindaswamy, Priya [Oak Ridge National Laboratory (ORNL); Karnowski, Thomas Paul [ORNL; Tennant, M [University of Alberta; Swainson, Stephen [University of Alberta

2008-01-01

80

A GMP-compliant protocol to expand and transfect cancer patient T cells with mRNA encoding a tumor-specific chimeric antigen receptor.  

PubMed

Chimeric antigen receptors (CARs), which combine an antibody-derived binding domain (single chain fragment variable) with T-cell-activating signaling domains, have become a promising tool in the adoptive cellular therapy of cancer. Retro- and lenti-viral transductions are currently the standard methods to equip T cells with a CAR; permanent CAR expression, however, harbors several risks like uncontrolled auto-reactivity. Modification of T cells by electroporation with CAR-encoding RNA to achieve transient expression likely circumvents these difficulties. We here present a GMP-compliant protocol to activate and expand T cells for clinical application. The protocol is optimized in particular to produce CAR-modified T cells in clinically sufficient numbers under full GMP-compliance from late-stage cancer patients. This protocol allows the generation of 6.7 × 10(8) CAR-expressing T cells from one patient leukapheresis. The CAR-engineered T cells produced pro-inflammatory cytokines after stimulation with antigen-bearing tumor cells and lysed tumor cells in an antigen-specific manner. This functional capacity was maintained after cryopreservation. Taken together, we provide a clinically applicable protocol to transiently engineer sufficient numbers of antigen-specific patient T cells for use in adoptive cell therapy of cancer. PMID:24938475

Krug, Christian; Wiesinger, Manuel; Abken, Hinrich; Schuler-Thurner, Beatrice; Schuler, Gerold; Dörrie, Jan; Schaft, Niels

2014-10-01

81

A Case of Aorto-Bronchial Fistula After Insertion of Left Main Bronchial Self-Expanding Metallic Stent in a Patient with Recurrent Esophageal Cancer  

SciTech Connect

We report a case of aorto-bronchial fistula (ABF) caused by a self-expanding metallic stent (EMS) 51 days after insertion into the left main bronchus. The patient presented with left main bronchial stenosis caused by post-operative local recurrence of esophageal cancer. Post-operative radio therapy totaling 40 Gy and post-recurrence radiotherapy totaling 34 Gy were administered, with daily fractions of 2 Gy. Stenosis of the left main bronchus improved slightly, and was followed with insertion of EMS to prevent re-stenosis. The patient experienced massive hemoptysis for 3 days before sudden death. Autopsy revealed the EMS edge perforating the descending aortic lumen. Tumor infiltration and bacterial infection were observed on the wall of the left bronchus, and atherosclerosis was present on the aortic wall around the fistula. It should be noted that the left main bronchus was at considerable risk of ABF after insertion of EMS for malignant stenosis, and prophylactic stent insertion into the bronchus without imperative need must be avoided.

Onishi, Hiroshi, E-mail: honishi@res.yamanashi-med.ac.jp; Kuriyama, Kengo; Komiyama, Takafumi; Tanaka, Shiho; Marino, Kan; Tsukamoto, Tatsuaki; Araki, Tsutomu [Yamanashi Medical University, Department of Radiation Oncology (Japan)

2004-09-15

82

Fox Chase study finds breast cancer patients face increasing number of imaging visits before surgery:  

Cancer.gov

Breast cancer patients frequently undergo imaging like mammograms or ultrasounds between their first breast cancer-related doctor visit and surgery to remove the tumor. In recent years, however, imaging has increased in dramatic and significant ways, say researchers from Fox Chase Cancer Center. More patients have repeat visits for imaging than they did 20 years ago, and single imaging appointments increasingly include multiple types of imaging.

83

Factor Analysis of the Expanded Prostate Cancer Index Composite in a Patient Group after Primary (External Beam Radiotherapy and Permanent Iodine125 Brachytherapy) and Postoperative Radiotherapy for Prostate Cancer  

Microsoft Academic Search

Background: The Expanded Prostate Cancer Index Composite questionnaire is widely used as a comprehensive assessment of health-related quality of life issues in prostate cancer management, distinguishing urinary, bowel, sexual, hormonal domains. The primary purpose of this study was to assess the factor structure of this questionnaire. Patients and Methods: A principal component analysis with orthogonal (varimax) rotation was conducted on

Eftychia Volz-Sidiropoulou; Michael Pinkawa; Karin Fischedick; Gerhard Jakse; Siegfried Gauggel; Michael J. Eble

2008-01-01

84

Registration of electronic portal images for patient set-up verification  

Microsoft Academic Search

Images acquired from an electronic portal imaging device are aligned with digitally reconstructed radiographs (DRRs) or other portal images to verify patient positioning during radiation therapy. Most of the currently available computer aided registration methods are based on the manual placement of corresponding landmarks. The purpose of the paper is twofold: (a) the establishment of a methodology for patient set-up

George K. Matsopoulos; Pantelis A. Asvestas; Konstantinos K. Delibasis; Vassilios Kouloulias; Nikolaos Uzunoglu; Pantelis Karaiskos; Panagiotis Sandilos

2004-01-01

85

A complete treatment of adult living donor liver transplantation: a review of surgical technique and current challenges to expand indication of patients.  

PubMed

The growing disparity between the number of liver transplant candidates and the supply of deceased donor organs has motivated the development of living donor liver transplantation (LDLT). Over the last two decades, the operation has been markedly improved by innovations rendering modern results comparable with those of deceased donor liver transplantation (DDLT). However, there remains room for further innovation, particularly in adult living donor liver transplantation (ALDLT). Unlike whole-size DDLT and pediatric LDLT, size-mismatching between ALDLT graft and recipient body weight and changing dynamics of posttransplant allograft regeneration have remained major challenges. A better understanding of the complex surgical anatomy and physiologic differences of ALDLT helps avoid small-for-size graft syndrome, graft congestion from outflow obstruction and graft hypoperfusion from portal flow steal. ALDLT for high-urgency patients (Model for End-Stage Liver Disease score >30) can achieve results comparable to DDLT in high volume centers. Size limitations of partial grafts and donor safety issues can be overcome with dual grafts and modified right-lobe grafts that preserve the donor's middle hepatic vein trunk. Extended application of LDLT for unresectable hepatocellular carcinoma above Milan criteria is an optional strategy at the cost of slightly compromised survival. ABO-blood group incompatibility obstacles have been broken down by introducing a paired donor exchange program and refined peri-operative management of ABO-incompatible ALDLT. This review focuses on recent innovations of surgical techniques, safe donor selection, current strategies to expand ALDLT with broadened patient selection criteria and important aspects of teamwork required for success. PMID:25358749

Lee, S-G

2015-01-01

86

Fundus autofluorescence imaging of patients with idiopathic macular hole  

PubMed Central

AIM To investigate the role of fundus autofluorescence (FAF) both in the diagnosis and the preoperative and postoperative evaluation of patients with idiopathic macular hole (MH). METHODS Forty eyes of 40 patients diagnosed as idiopathic MH between May 2010 and May 2011 were included in this retrospective study. All patients underwent full ophthalmologic examinations and imagings including fluorescein angiography, fundus autofluorescence (FAF) and optical coherence tomography. Thirty of these patients underwent MH surgery. FAF findings were associated with duration of symptoms, visual acuity at presentation, stage of MH, and postoperative anatomical correction. RESULTS The mean duration of patients' symptoms was 3.8±2.0 (1–9) months. The MH was stage 2 in 4 (10%), stage 3 in 24 (60%) and stage 4 in 12 (30%) eyes. The median preoperative best corrected visual acuity was 20/200 (between 20/800 and 20/100). Twenty-eight of cases (70%) showed a stellate appearance with dark radiating striae. Having a visual acuity ?20/200 was significantly more common in eyes with stellate appearance (P<0.001). The mean duration of symptoms was significantly shorter in eyes with stellate appearance (2.75±0.8 vs 6.33±1.61 months) (P<0.001). The frequency of stage 4 MH was significantly higher in eyes with non-stellate appearance (P<0.001). Anatomical correction of MH was achieved in 91.3% (21/23) of eyes with stellate appearance and 71.4% (5/7) of eyes without this appearance (P=0.225). CONCLUSION Stellate appearance in FAF is associated with earlier stages of macular hole, better visual acuity at presentation, shorter duration of symptoms, thus more favorable prognosis. PMID:24195050

Teke, Mehmet Yasin; Cakar-Ozdal, Pinar; ?en, Emine; Elgin, Ufuk; Nalcac?oglu-Yuksekkaya, Pinar; Ozturk, Faruk

2013-01-01

87

Radiographic imaging for patients with contagious infectious diseases: how to acquire chest radiographs of patients infected with the ebola virus.  

PubMed

OBJECTIVE. Contagious infectious diseases add a new dimension to radiology and pose many unanswered questions. In particular, what is the safest way to image patients with contagious and potentially lethal infectious diseases? Here, we describe protocols used by Emory University to successfully acquire chest radiographs of patients with Ebola virus disease. CONCLUSION. Radiology departments need to develop new protocols for various modalities used in imaging patients with contagious and potentially lethal infectious diseases. PMID:25402496

Auffermann, William F; Kraft, Colleen S; Vanairsdale, Sharon; Lyon, G Marshall; Tridandapani, Srini

2015-01-01

88

Visual search performance of patients with vision impairment: effect of JPEG image enhancement  

E-print Network

Visual search performance of patients with vision impairment: effect of JPEG image enhancement Gang & Peli E. Visual search performance of patients with vision impairment: effect of JPEG image enhancement option for patients with vision impairment resulting from loss of visual acuity and or contrast

Peli, Eli

89

Correlation of PET Images of Metabolism, Proliferation and Hypoxia to Characterize Tumor Phenotype in Patients with Cancer of the Oropharynx  

PubMed Central

Spatial organization of tumor phenotype is of great interest to radiotherapy target definition and outcome prediction. We characterized tumor phenotype in patients with cancers of the oropharynx through voxel-based correlation of PET images of metabolism, proliferation, and hypoxia. Methods Patients with oropharyngeal cancer received 18F-fluorodeoxyglucose (FDG) PET/CT, 18F-fluorothymidine (FLT) PET/CT, and 61Cu-diacetyl-bis(N4-methylthiosemicarbazone) (Cu-ATSM) PET/CT. Images were co-registered and standardized uptake values (SUV) were calculated for all modalities. Voxel-based correlation was evaluated with Pearson’s correlation coefficient in tumor regions. Additionally, sensitivity studies were performed to quantify the effects of image segmentation, registration, noise, and segmentation on R. Results On average, FDG PET and FLT PET images were most highly correlated (RFDG:FLT=0.76, range 0.53–0.85), while Cu-ATSM PET showed greater heterogeneity in correlation to other tracers (RFDG:Cu-ATSM=0.64, range 0.51–0.79; RFLT:Cu-ATSM=0.61, range 0.21–0.80). Of the tested parameters, correlation was most sensitive to image registration. Misregistration of one voxel lead to ?RFDG=0.25, ?RFLT=0.39, and ?RCu-ATSM=0.27. Image noise and reconstruction also had quantitative effects on correlation. No significant quantitative differences were found between GTV, expanded GTV, or CTV regions. Conclusions Voxel-based correlation represents a first step into understanding spatial organization of tumor phenotype. These results have implications for radiotherapy target definition and provide a framework to test outcome prediction based on pretherapy distribution of phenotype. PMID:23068711

Nyflot, Matthew J; Harari, Paul M; Yip, Stephen; Perlman, Scott B; Jeraj, Robert

2012-01-01

90

[Imaging modalities and therapy options in patients with acute flank pain].  

PubMed

The objective of this article is the description of imaging techniques for the evaluation of patients with acute flank pain and suspicion of urolithiasis and the impact of these techniques in the therapy management of patients with calculi. PMID:24981448

Grosse, A; Grosse, C

2014-07-01

91

Measurement of patient imaging dose for real-time kilovoltage x-ray intrafraction tumour position monitoring in prostate patients  

NASA Astrophysics Data System (ADS)

The dose for image-based motion monitoring of prostate tumours during radiotherapy delivery has not been established. This study aimed to provide quantitative analysis and optimization of the fluoroscopic patient imaging dose during radiotherapy for IMRT and VMAT treatments using standard and hypofractionated treatment schedules. Twenty-two patients with type T1c N0/M0 prostate cancer and three implanted fiducial markers were considered. Minimum field sizes encompassing all fiducial markers plus a 7.5 mm motion margin were determined for each treatment beam, each patient and the complete cohort. Imaging doses were measured for different field sizes and depths in a phantom at 75 and 120 kV. Based on these measurements, the patient imaging doses were then estimated according to beam-on time for clinical settings. The population minimum field size was 5.3 × 6.1 cm2, yielding doses of 406 and 185 mGy over the course of an IMRT treatment for 75 kV (10 mAs) and 120 kV (1.04 mAs) imaging respectively, at 1 Hz. The imaging dose was reduced by an average of 28% and 32% by adopting patient-specific and treatment-beam-specific field sizes respectively. Standard fractionation VMAT imaging doses were 37% lower than IMRT doses over a complete treatment. Hypofractionated IMRT stereotactic body radiotherapy (SBRT) and VMAT SBRT imaging doses were 58% and 76% lower than IMRT doses respectively. The patient dose for kilovoltage intrafraction monitoring of the prostate was quantified. Tailoring imaging field sizes to specific patients yielded a significant reduction in the imaging dose, as did adoption of faster treatment modalities such as VMAT.

Crocker, James K.; Aun Ng, Jin; Keall, Paul J.; Booth, Jeremy T.

2012-05-01

92

Measurement of patient imaging dose for real-time kilovoltage x-ray intrafraction tumour position monitoring in prostate patients.  

PubMed

The dose for image-based motion monitoring of prostate tumours during radiotherapy delivery has not been established. This study aimed to provide quantitative analysis and optimization of the fluoroscopic patient imaging dose during radiotherapy for IMRT and VMAT treatments using standard and hypofractionated treatment schedules. Twenty-two patients with type T1c N0/M0 prostate cancer and three implanted fiducial markers were considered. Minimum field sizes encompassing all fiducial markers plus a 7.5 mm motion margin were determined for each treatment beam, each patient and the complete cohort. Imaging doses were measured for different field sizes and depths in a phantom at 75 and 120 kV. Based on these measurements, the patient imaging doses were then estimated according to beam-on time for clinical settings. The population minimum field size was 5.3 × 6.1 cm², yielding doses of 406 and 185 mGy over the course of an IMRT treatment for 75 kV (10 mAs) and 120 kV (1.04 mAs) imaging respectively, at 1 Hz. The imaging dose was reduced by an average of 28% and 32% by adopting patient-specific and treatment-beam-specific field sizes respectively. Standard fractionation VMAT imaging doses were 37% lower than IMRT doses over a complete treatment. Hypofractionated IMRT stereotactic body radiotherapy (SBRT) and VMAT SBRT imaging doses were 58% and 76% lower than IMRT doses respectively. The patient dose for kilovoltage intrafraction monitoring of the prostate was quantified. Tailoring imaging field sizes to specific patients yielded a significant reduction in the imaging dose, as did adoption of faster treatment modalities such as VMAT. PMID:22517054

Crocker, James K; Ng, Jin Aun; Keall, Paul J; Booth, Jeremy T

2012-05-21

93

Patient-controlled sharing of medical imaging data across unaffiliated healthcare organizations  

PubMed Central

Background Current image sharing is carried out by manual transportation of CDs by patients or organization-coordinated sharing networks. The former places a significant burden on patients and providers. The latter faces challenges to patient privacy. Objective To allow healthcare providers efficient access to medical imaging data acquired at other unaffiliated healthcare facilities while ensuring strong protection of patient privacy and minimizing burden on patients, providers, and the information technology infrastructure. Methods An image sharing framework is described that involves patients as an integral part of, and with full control of, the image sharing process. Central to this framework is the Patient Controlled Access-key REgistry (PCARE) which manages the access keys issued by image source facilities. When digitally signed by patients, the access keys are used by any requesting facility to retrieve the associated imaging data from the source facility. A centralized patient portal, called a PCARE patient control portal, allows patients to manage all the access keys in PCARE. Results A prototype of the PCARE framework has been developed by extending open-source technology. The results for feasibility, performance, and user assessments are encouraging and demonstrate the benefits of patient-controlled image sharing. Discussion The PCARE framework is effective in many important clinical cases of image sharing and can be used to integrate organization-coordinated sharing networks. The same framework can also be used to realize a longitudinal virtual electronic health record. Conclusion The PCARE framework allows prior imaging data to be shared among unaffiliated healthcare facilities while protecting patient privacy with minimal burden on patients, providers, and infrastructure. A prototype has been implemented to demonstrate the feasibility and benefits of this approach. PMID:22886546

Ahn, David K; Unde, Bhagyashree; Gage, H Donald; Carr, J Jeffrey

2013-01-01

94

Early molecular imaging of interstitial changes in patients after myocardial infarction: Comparison with delayed contrast-enhanced magnetic resonance imaging  

PubMed Central

Introduction The clinical feasibility of noninvasive imaging of interstitial alterations after myocardial infarction (MI) was assessed using a technetium-99m-labeled RGD imaging peptide (RIP). In experimental studies, RIP has been shown to target integrins associated with collagen-producing myofibroblasts (MFB). Methods and Results Ten patients underwent myocardial perfusion imaging (MPI) within the first week after MI. At 3 and 8 weeks after MI, RIP was administered intravenously and SPECT images acquired for interstitial imaging. RIP imaging was compared to initial MPI and to the extent of scar formation defined by late gadolinium-enhanced (LGE) cardiac magnetic resonance (CMR) imaging 1 year after MI. RIP uptake was observed in 7 of the 10 patients at both 3 and 8 weeks. Although, RIP uptake corresponded to areas of perfusion defects, it usually extended beyond the infarct zone to a variable extent; 2 of 7 patients showed tracer uptake throughout myocardium. In all positive cases, RIP uptake was similar to the extent of scar observed at 1 year by LGE-CMR imaging. Conclusion This study demonstrates that RGD-based imaging early after MI may predict the eventual extent of scar formation, which often exceeds initial MPI deficit but colocalizes with LGE in CMR imaging performed subsequently. PMID:20658273

Verjans, Johan; Wolters, Sander; Laufer, Ward; Schellings, Mark; Lax, Michelle; Lovhaug, Dagfinn; Boersma, Hendrikus; Kemerink, Gerrit; Schalla, Simon; Gordon, Paul; Teule, Jaap

2010-01-01

95

An Adaptive Approach to Decomposing Patient-Motion Tracking Data Acquired During Cardiac SPECT Imaging  

Microsoft Academic Search

Patient motion during cardiac SPECT imaging can cause diagnostic imaging artifacts. We have implemented a Neural Network (NN) approach to decompose monitored patient motion data, gathered during cardiac SPECT imaging, using the Polaris stereo-IR real-time motion-tracking system. Herein, we show the successful decomposition of Polaris motion data into rigid body motion (RBM) and respiratory motion (RM). The motivation for separating

Richard D. Beach; Hans Depold; Guido Boening; Philippe P. Bruyant; Bing Feng; Howard C. Gifford; Michael A. Gennert; Suman Nadella; Michael A. King

2007-01-01

96

Vibration Response Imaging (VRI) of the Lungs in Pediatric Patients  

Microsoft Academic Search

Background: Pediatric chest imaging such as chest radiology and computed tomography largely contribute to the diagnosis and management of pediatric pulmonary disorders 1 . However, these technologies emit radiation 2 and cannot detect the whole range of pulmonary complaints 3,4 . Vibration Response Imaging (VRI) is a novel technology providing a non-invasive, radiation free dynamic image of the lungs. A

G. Livnat; F. Hakim; L. Bentur

97

Patterns of Acute Cerebral Infarcts in Patients with Active Malignancy Using Diffusion-Weighted Imaging  

Microsoft Academic Search

Background and Purpose: It is still controversial whether the nature of cerebral infarcts differs between cancer patients and the general population. The aim of this study is to delineate the characteristics of acute cerebral infarction in patients with active malignancy using diffusion-weighted imaging (DWI). Materials and Methods: Seventy consecutive patients with both active malignancy and acute cerebral infarction (confirmed by

Chien-Tai Hong; Li-Kai Tsai; Jiann-Shing Jeng

2009-01-01

98

Value of Surgery In Patients With Negative Imaging And Sporadic Zollinger-Ellison Syndrome (ZES)  

PubMed Central

Objectives To address the value of surgery in sporadic Zollinger-Ellison syndrome (ZES) patients with negative imaging studies. Background Medical control of acid hypersecretion in patients with sporadic Zollinger-Ellison syndrome (ZES) is highly effective. This has led to these patients frequently not sent to surgery, especially if preoperative imaging studies are negative, due in large part because almost no data exists on the success of surgery in this group. Methods 58 prospectively studied sporadic ZES patients (17% of total studied) had negative imaging studies and their surgical outcome was compared to 117 patients with positive imaging results. Results 35 patients had negative imaging in the pre-somatostatin receptor scintigraphy era (SRS) and 23 in the post-SRS era. The image negative patients had long disease histories prior to surgery (mean±SEM, from onset=7.9±1[range ?0.25-35 yrs]) and 25% were followed ?2yrs from diagnosis. At surgery, gastrinoma was found in 57/58 patients (98%). Tumors were small (mean=0.8cm, 60% < 1 cm). The most common primary sites were: duodenal 64%, pancreatic 17%, and lymph node (LN)(10%). 50% had a primary only, 41% primary + LN, and 7% had liver metastases. 35/58(60%) were cured immediately postoperatively and at last follow-up [mean-9.4yrs, range 0.2-22yrs], 27 patients (46%) remained cured. During follow-up 3 patients died, each was found to have liver metastases at surgery. In comparison to the image positive patients, those with negative imaging had lower preop fasting gastrin levels; a longer delay prior to surgery; more frequently had a small duodenal tumors; less frequently had a pancreatic tumor, multiple tumors or developed a new lesion postoperatively and had a longer survival. Conclusions Imaging negative sporadic ZES patients are not rare even in the post-SRS period. An experienced surgeon can find gastrinoma in almost every patient (98%) and nearly one-half (46%) are cured, a rate similar to imaging positive tumor patients. Because liver metastases were found in 7%, which may have been caused by a long delay in surgery and all the disease-related deaths occurred in this group, surgery should be routinely undertaken early in ZES patients despite negative imaging studies. PMID:22868363

Norton, Jeffrey A.; Fraker, Douglas L.; Alexander, H. Richard; Jensen, Robert T

2012-01-01

99

Patient specific dynamic geometric models from sequential volumetric time series image data.  

PubMed

Generating patient specific dynamic models is complicated by the complexity of the motion intrinsic and extrinsic to the anatomic structures being modeled. Using a physics-based sequentially deforming algorithm, an anatomically accurate dynamic four-dimensional model can be created from a sequence of 3-D volumetric time series data sets. While such algorithms may accurately track the cyclic non-linear motion of the heart, they generally fail to accurately track extrinsic structural and non-cyclic motion. To accurately model these motions, we have modified a physics-based deformation algorithm to use a meta-surface defining the temporal and spatial maxima of the anatomic structure as the base reference surface. A mass-spring physics-based deformable model, which can expand or shrink with the local intrinsic motion, is applied to the metasurface, deforming this base reference surface to the volumetric data at each time point. As the meta-surface encompasses the temporal maxima of the structure, any extrinsic motion is inherently encoded into the base reference surface and allows the computation of the time point surfaces to be performed in parallel. The resultant 4-D model can be interactively transformed and viewed from different angles, showing the spatial and temporal motion of the anatomic structure. Using texture maps and per-vertex coloring, additional data such as physiological and/or biomechanical variables (e.g., mapping electrical activation sequences onto contracting myocardial surfaces) can be associated with the dynamic model, producing a 5-D model. For acquisition systems that may capture only limited time series data (e.g., only images at end-diastole/end-systole or inhalation/exhalation), this algorithm can provide useful interpolated surfaces between the time points. Such models help minimize the number of time points required to usefully depict the motion of anatomic structures for quantitative assessment of regional dynamics. PMID:15544239

Cameron, B M; Robb, R A

2004-01-01

100

Expanded-function Auxiliaries in General Dentistry  

PubMed Central

A simulation model of private dental practice has been developed to evaluate the effects of introducing expanded-function auxiliary personnel. The model permits the experimental investigation of a variety of staffing patterns and facility configurations. Results indicate that a solo practice can expand its patient volume 169 percent and increase net revenue 233 percent by adding expanded-function auxiliaries, while simultaneously reducing patient waiting time and the time spent at chairside by the dentist. Field validations of the simulation results are described. PMID:4652600

Kilpatrick, Kerry E.; Mackenzie, Richard S.; Delaney, Allen G.

1972-01-01

101

Who am I? Reflections on self-image among patients with cancer in clinical trials.  

PubMed

Patients with cancer who participate in research face difficult challenges. Their lives change in many ways, and they often question their self-image. Self-image includes how patients see themselves and who they want to become. The current commentary addresses the issue of self-image in patients with cancer who participate in clinical trials and how their sense of who they were changes as they shift from patients with cancer to research participants. Patients with cancer who participate in research may suffer from multiple identity transitions, ranging from physical alterations in appearance and bodily capabilities to psychological burdens of job loss and the inability to contribute financially to their families. The author aims to provide insight as to how researchers can help patients find meaning in their lives during the process of participation in clinical trials as they undergo identity transitions. PMID:24305493

Ulrich, Connie M

2013-12-01

102

Prognostic value of intravenous dipyridamole thallium imaging in patients with diabetes mellitus considered for renal transplantation  

SciTech Connect

Patients with diabetes and end-stage renal failure are known to have a high risk for cardiac morbidity and mortality associated with renal transplantation. The most efficient method to determine preoperative cardiac risk has not been established. To determine the effectiveness of intravenous dipyridamole thallium imaging in predicting cardiac events, 40 diabetic renal transplant candidates were studied preoperatively in a prospective trial. The study group consisted of 40 patients whose average age was 42 years (range 27 to 64); 34 (85%) were hypertensive and 21 (53%) were cigarette smokers. Cardiac history included chest pain in 6 patients and prior myocardial infarction in 3 patients. Dipyridamole thallium imaging showed reversible defects in 9 patients, fixed defects in 8 patients and normal scans in 23 patients. Dipyridamole thallium imaging was performed using 0.56 mg/kg of dipyridamole infused intravenously over 4 minutes. Cardiac events occurred only in patients with reversible thallium defects, of which there were 6. Of these 6 patients, 3 had cardiac events before transplantation and 3 had them in the early postoperative phase (within 6 weeks of surgery). Of 21 patients who underwent renal transplantation, 3 had cardiac events within 6 weeks of transplantation. The average duration of follow-up was 11 months (range 1 to 21). Thus, dipyridamole thallium imaging is an effective method of identifying renal transplant candidates likely to develop cardiac complications. Routine coronary angiography may not be necessary to screen all renal transplant candidates for coronary artery disease before surgery.

Camp, A.D.; Garvin, P.J.; Hoff, J.; Marsh, J.; Byers, S.L.; Chaitman, B.R. (St. Louis Univ. School of Medicine, MO (USA))

1990-06-15

103

Self-image and perception of mother and father in psychotic and borderline patients.  

PubMed

Psychotic and borderline patients rated their self-image and their perception of their mother and father using the Structural Analysis of Social Behavior model (SASB). The borderline patients had more negative images of themselves and their parents, especially their fathers, than did the psychotic patients and the normal subjects, while the psychotic patients' ratings did not differ much from those of the normal subjects. The self-image was related to the images of both parents for borderline patients and normal subjects, while for the psychotic patients only the image of the mother was important for the self-image. In addition, the psychotic patients did not differentiate between the poles of control and autonomy in the introjected self-image. It was concluded that borderline patients are characterized by negative attachment, while psychotic patients are characterized by poor separation from the mother and poor differentiation between autonomy and control. The paper also discusses how this may influence the patients' relations to others. Psychotische und Borderline Patienten beurteilten ihr Selbstbild und ihre Wahrnehmung von Mutter und Vater mit Hilfe der strukturalen Analyse sozialen Verhaltens (SASB). Die Borderline Patienten hattten negativere Selbstbilder und Elternbilder (speziell Vaterbilder) als die psychotischen Patienten und gesunde Personen. Die Beurteilungen der psychotischen Patienten unterschieden sich dagegen nicht besonders von jenen Gesunder. Das Selbstbild stand in Beziehung zu beiden Elternbildern bei den Borderline Patienten und den Gesunden, während bei den psychotischen Patienten nur das Mutterbild für das Selbstbild bedeutsam war. Außerdem konnte bei den psychotischen Patienten nicht zwischen den Polen der Kontrolle und Autonomie bzgl. der introjizierten Selbstbilder differenziert werden. Aus den Ergebnissen wird gefolgert, dass Borderline Patienten durch eine negative Bindung charackterisiert sind, psychotische Patienten dagegen durch eine mangelnde Separation von ihren Müttern und eine geringe Differenzierung zwischen Autonomie und Kontrolle. Es wird außerdem diskutiert, wie die Ergebnisse auf die realen Beziehungen der Patienten zu anderen Menschen Einflus nehmen könnten. Des patients psychotiques et Borderline ont évalué leur image d'eux-mêmes et leur perception de leur mère et père à l'aide du modèle de l'Analyse Structural du Comportement Social (SASB. Les patients Borderline avaient des imagess plus négatives d'eux-mêmes et de leurs parents, surtout de leur père, que les patients psychotiques et les sujets normaux, alors que les patients psychotiques se jugeaient à peine différemment des sujets normaux. L'image de soi était en relation avec les images des deux parents pour les patients Borderline et pour les sujets normaux, alors que pour les patients psychotiques, seulement l'image de la mère jouait un rôle pour leur image. En plus, les patients psychotiques ne différenciaient pas entre les pôles de contrôle et d'autonomie dans l'image de soi introjectée. Nous en avons conclu que les patients Borderline se caractérisent par un attachement négatif, et les patients psychotiques par une faible séparation de la mère ainsi qu'une différenciation modeste entre autonomie et contrôle. L'influence de ceci sur les relations des patients avec les autrs est discutée dans cet article. Pacientes limítrofes y psicóticos evaluaron su autoimagen y la percepción que tenían de sus padres usando el modelo de Análisis estructural del comportamiento social (SASB). Los pacientes limítrofes registraron imágenes más negativas de sí mismos y de sus progenitores, especialmente de su padre, que los pacientes psicóticos y los normales, mientras que las evaluaciones de los pacientes psicóticos no difirieron mucho de las de los sujetos normales. La autoimagen tuvo relación con la imagen de ambos progenitores tanto en el caso de los pacientes limítrofes como de los sujetos normales, mientras que para los pacientes psicóticos no diferenciaron entre control y autonomía en la a

Armelius, K; Granberg

2000-02-01

104

Towards adapting a normal patient database for SPECT brain perfusion imaging  

NASA Astrophysics Data System (ADS)

Single-photon emission computerized tomography (SPECT) is a tool which can be used to image perfusion in the brain. Clinicians can use such images to help diagnose dementias such as Alzheimer's disease. Due to the intrinsic stochasticity in the photon imaging system, some form of statistical comparison of an individual image with a 'normal' patient database gives a clinician additional confidence in interpreting the image. Due to the variations between SPECT camera systems, ideally a normal patient database is required for each individual system. However, cost or ethical considerations often prohibit the collection of such a database for each new camera system. Some method of adapting existing normal patient databases to new camera systems would be beneficial. This paper introduces a method which may be regarded as a 'first-pass' attempt based on 2-norm regularization and a codebook of discrete spatially stationary convolutional kernels. Some preliminary illustrative results are presented, together with discussion on limitations and possible improvements.

Smith, N. D.; Holmes, R. B.; Soleimani, M.; Evans, M. J.; Cade, S. C.; Mitchell, C. N.

2012-06-01

105

Conventional magnetic resonance imaging features in patients with tropical spastic paraparesis  

Microsoft Academic Search

Conventional brain and spinal cord magnetic resonance images were performed in 21 patients with human T-cell lymphotropic\\u000a virus (HTLV)-1 associated myelopathy\\/tropical spastic paraparesis, to assess the role of conventional magnetic resonance imaging\\u000a (MRI) in the disease diagnosis. These patients had no other central nervous system conditions or related risk factors at the\\u000a time of tropical spastic paraparesis diagnosis. Eleven (52.4%)

Francesca Bagnato; John A. Butman; Carlos A. Mora; Shiva Gupta; Yoshima Yamano; Talin A. Tasciyan; Jeffrey M. Solomon; Waldyr J. Santos; Roger D. Stone; Henry F. McFarland; Steven Jacobson

2005-01-01

106

Combination of Image Registration Algorithms for Patient Alignement in Proton Beam Therapy  

Microsoft Academic Search

\\u000a We propose a measure of patient alignment in a video by combining different image representations : grey level, edges, and\\u000a a set of feature points. When patient head is correctly positionned, a reference image with its ellipse is stored as a template\\u000a of correct alignment. Edges detection results in a second template of the correct head location. Corners inside the

Rachid Belaroussi; Guillaume Morel

2008-01-01

107

Registration of electronic portal images for patient set-up verification.  

PubMed

Images acquired from an electronic portal imaging device are aligned with digitally reconstructed radiographs (DRRs) or other portal images to verify patient positioning during radiation therapy. Most of the currently available computer aided registration methods are based on the manual placement of corresponding landmarks. The purpose of the paper is twofold: (a) the establishment of a methodology for patient set-up verification during radiotherapy based on the registration of electronic portal images, and (b) the evaluation of the proposed methodology in a clinical environment. The estimation of set-up errors, using the proposed methodology, can be accomplished by matching the portal image of the current fraction of the treatment with the portal image of the baseline treatment (reference portal image) using a nearly automated technique. The proposed registration method is tested on a number of phantom data as well as on data from four patients. The phantom data included portal images that corresponded to various positions of the phantom on the treatment couch. For each patient, a set of 30 portal images was used. For the phantom data (for both transverse and lateral portal images), the maximum absolute deviations of the translational shifts were within 1.5 mm, whereas the in-plane rotation angle error was less than 0.5 degrees. The two-way Anova revealed no statistical significant variability both within observer and between-observer measurements (P > 0.05). For the patient data, the mean values obtained with manual and the proposed registration methods were within 0.5 mm. In conclusion, the proposed registration method has been incorporated within a system, called ESTERR-PRO. Its image registration capability achieves high accuracy and both intra- and inter-user reproducibility. The system is fully operational within the Radiotherapy Department of 'HYGEIA' Hospital in Athens and it could be easily installed in any other clinical environment since it requires standardized hardware specifications and minimal human intervention. PMID:15357197

Matsopoulos, George K; Asvestas, Pantelis A; Delibasis, Konstantinos K; Kouloulias, Vassilios; Uzunoglu, Nikolaos; Karaiskos, Pantelis; Sandilos, Panagiotis

2004-07-21

108

Occupational and patient exposure as well as image quality for full spine examinations with the EOS imaging system  

SciTech Connect

Purpose: EOS (EOS imaging S.A, Paris, France) is an x-ray imaging system that uses slot-scanning technology in order to optimize the trade-off between image quality and dose. The goal of this study was to characterize the EOS system in terms of occupational exposure, organ doses to patients as well as image quality for full spine examinations. Methods: Occupational exposure was determined by measuring the ambient dose equivalents in the radiological room during a standard full spine examination. The patient dosimetry was performed using anthropomorphic phantoms representing an adolescent and a five-year-old child. The organ doses were measured with thermoluminescent detectors and then used to calculate effective doses. Patient exposure with EOS was then compared to dose levels reported for conventional radiological systems. Image quality was assessed in terms of spatial resolution and different noise contributions to evaluate the detector's performances of the system. The spatial-frequency signal transfer efficiency of the imaging system was quantified by the detective quantum efficiency (DQE). Results: The use of a protective apron when the medical staff or parents have to stand near to the cubicle in the radiological room is recommended. The estimated effective dose to patients undergoing a full spine examination with the EOS system was 290?Sv for an adult and 200 ?Sv for a child. MTF and NPS are nonisotropic, with higher values in the scanning direction; they are in addition energy-dependent, but scanning speed independent. The system was shown to be quantum-limited, with a maximum DQE of 13%. The relevance of the DQE for slot-scanning system has been addressed. Conclusions: As a summary, the estimated effective dose was 290?Sv for an adult; the image quality remains comparable to conventional systems.

Damet, J., E-mail: jerome.damet@chuv.ch; Fournier, P.; Monnin, P.; Sans-Merce, M.; Verdun, F. R.; Baechler, S. [Institute of Radiation Physics, Lausanne University Hospital, Lausanne 1007 (Switzerland)] [Institute of Radiation Physics, Lausanne University Hospital, Lausanne 1007 (Switzerland); Ceroni, D. [Department of Paediatrics, Division of paediatric orthopaedic, University Hospitals of Geneva, Geneva 1205 (Switzerland)] [Department of Paediatrics, Division of paediatric orthopaedic, University Hospitals of Geneva, Geneva 1205 (Switzerland); Zand, T. [Department of Radiology, Division of paediatric radiology, University Hospitals of Geneva, Geneva 1205 (Switzerland)] [Department of Radiology, Division of paediatric radiology, University Hospitals of Geneva, Geneva 1205 (Switzerland)

2014-06-15

109

Computer-aided prognosis: predicting patient and disease outcome via multi-modal image analysis  

Microsoft Academic Search

Computer-aided prognosis (CAP) is a new and exciting complement to the field of computer-aided diagnosis (CAD) and involves developing computerized image analysis and multi-modal data fusion algorithms for helping physicians predict disease outcome and patient survival. At the Laboratory for Computational Imaging and Bioinformatics (LCIB) at Rutgers University we have been developing computerized algorithms for high dimensional data and image

Anant Madabhushi; Ajay Basavanhally; Scott Doyle; Shannon Agner; George Lee

2010-01-01

110

Gd-DTPA-Enhanced MR Imaging of the Brain in Patients with Meningitis: Comparison with CT  

Microsoft Academic Search

Plain and Gd-DTPA-enhanced MR images of the brain were obtained in 18 consecutive patients with meningitis (eight with tuberculous, five with bacterial, three with viral, and two with fungal infections); the MR images were compared with CT scans. MR images were obtained on a 2.O-T superconducting unit with both Ti- and T2-weighted pulse sequences before injectionand with a TI-weighted sequence

Kee Hyun Chang; Moon Hee Han; Jae Kyu Roh; Man Chung Han; Chu-Wan Kim

111

A knowledge-based imaging informatics approach to managing patients treated with proton beam therapy  

Microsoft Academic Search

Last year we presented work on an imaging informatics approach towards developing quantitative knowledge and tools based on standardized DICOM-RT objects for Image-Guided Radiation Therapy. In this paper, we have extended this methodology to perform knowledge-based medical imaging informatics research on specific clinical scenarios where brain tumor patients are treated with Proton Beam Therapy (PT). PT utilizes energized charged particles,

B. J. Liu; H. K. Huang; M. Law; Anh Le; Jorge Documet; Arek Gertych

2007-01-01

112

Elements of the patient-centered medical home associated with health outcomes among veterans: the role of primary care continuity, expanded access, and care coordination.  

PubMed

Care continuity, access, and coordination are important features of the patient-centered medical home model and have been emphasized in the Veterans Health Administration patient-centered medical home implementation, called the Patient Aligned Care Team. Data from more than 4.3 million Veterans were used to assess the relationship between these attributes of Patient Aligned Care Team and Veterans Health Administration hospitalization and mortality. Controlling for demographics and comorbidity, we found that continuity with a primary care provider was associated with a lower likelihood of hospitalization and mortality among a large population of Veterans receiving VA primary care. PMID:25180648

Nelson, Karin; Sun, Haili; Dolan, Emily; Maynard, Charles; Beste, Laruen; Bryson, Christopher; Schectman, Gordon; Fihn, Stephan D

2014-01-01

113

Abnormal brain magnetic resonance imaging in two patients with Smith-Magenis syndrome.  

PubMed

Smith-Magenis syndrome (SMS) is a clinically recognizable contiguous gene syndrome ascribed to an interstitial deletion in chromosome 17p11.2. Seventy percent of SMS patients have a common deletion interval spanning 3.5 megabases (Mb). Clinical features of SMS include characteristic mild dysmorphic features, ocular anomalies, short stature, brachydactyly, and hypotonia. SMS patients have a unique neurobehavioral phenotype that includes intellectual disability, self-injurious behavior and severe sleep disturbance. Little has been reported in the medical literature about anatomical brain anomalies in patients with SMS. Here we describe two patients with SMS caused by the common deletion in 17p11.2 diagnosed using chromosomal microarray (CMA). Both patients had a typical clinical presentation and abnormal brain magnetic resonance imaging (MRI) findings. One patient had subependymal periventricular gray matter heterotopia, and the second had a thin corpus callosum, a thin brain stem and hypoplasia of the cerebellar vermis. This report discusses the possible abnormal MRI images in SMS and reviews the literature on brain malformations in SMS. Finally, although structural brain malformations in SMS patients are not a common feature, we suggest baseline routine brain imaging in patients with SMS in particular, and in patients with chromosomal microdeletion/microduplication syndromes in general. Structural brain malformations in these patients may affect the decision-making process regarding their management. PMID:24788350

Maya, Idit; Vinkler, Chana; Konen, Osnat; Kornreich, Liora; Steinberg, Tamar; Yeshaya, Josepha; Latarowski, Victoria; Shohat, Mordechai; Lev, Dorit; Baris, Hagit N

2014-08-01

114

Clinical Application of 3D-FIESTA Image in Patients with Unilateral Inner Ear Symptom  

PubMed Central

Background and Objectives Unilateral auditory dysfunction such as tinnitus and hearing loss could be a warning sign of a retrocochlear lesion. Auditory brainstem response (ABR) and internal auditory canal magnetic resonance image (MRI) are suggested as novel diagnostic tools for retrocochlear lesions. However, the high cost of MRI and the low sensitivity of the ABR test could be an obstacle when assessing patients with unilateral ear symptoms. The purpose of this study was to introduce the clinical usefulness of three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) MRI in patients with unilateral ear symptoms. Subjects and Methods Two hundred and fifty-three patients with unilateral tinnitus or unilateral hearing loss who underwent 3D-FIESTA temporal bone MRI as a screening test were enrolled. We reviewed the abnormal findings in the 3D-FIESTA images and ear symptoms using the medical records. Results In patients with unilateral ear symptoms, 51.0% of the patients had tinnitus and 32.8% patients were assessed to have sudden sensory neural hearing loss. With 3D-FIESTA imaging, twelve patients were diagnosed with acoustic neuroma, four with enlarged vestibular aqueduct syndrome, and two with posterior inferior cerebellar artery aneurysm. Inner ear anomalies and vestibulocochlear nerve aplasia could be diagnosed with 3D-FIESTA imaging. Conclusions 3D-FIESTA imaging is a highly sensitive method for the diagnosis of cochlear or retrocochlear lesions. 3D-FIESTA imaging is a useful screening tool for patients with unilateral ear symptoms. PMID:24653918

Oh, Jae Ho; Chung, Jae Ho; Min, Hyun Jung; Cho, Seok Hyun; Park, Chul Won

2013-01-01

115

Measurement of sacroiliac joint stiffness in peripartum pelvic pain patients with Doppler imaging of vibrations (DIV)  

Microsoft Academic Search

Objectives. The research question of the present study was: are sacroiliac joint stiffness levels of peripartum pelvic pain patients different from those of healthy subjects?Study design. A cross-sectional comparative sacroiliac joint stiffness analysis of peripartum pelvic pain patients with healthy subjects. In previous studies we introduced a new technique, Doppler imaging of vibrations (DIV), to assess sacroiliac joint stiffness using

H. Muzaffer Buyruk; Hendrik J. Stam; Christian J. Snijders; Johan S. Laméris; Wim P. J. Holland; Theo H. Stijnen

1999-01-01

116

Patent foramen ovale size and embolic brain imaging findings among patients with ischemic stroke  

Microsoft Academic Search

Background and Purpose—Although the cause of stroke among patients with patent foramen ovale (PFO) may be due to paradoxical cerebral embolism (PCE), this mechanism is often difficult to prove. The aim of our study was to evaluate the association between brain imaging findings suggestive of embolism and PFO among ischemic stroke patients. Methods—As part of the Northern Manhattan Stroke Study,

Michaela M. Steiner; Di Tullio; Tanja Rundek; Robert Gan; Xun Chen; Chiara Liguori; Michael Brainin; Shunichi Homma; Ralph L. Sacco

1998-01-01

117

Joint Simulation of Transmission X-ray Imaging on GPU and Patient's Respiration on CPU  

E-print Network

Joint Simulation of Transmission X-ray Imaging on GPU and Patient's Respiration on CPU F. P. Vidal1's respiration on the CPU. It has been initially deployed into a medical simulator for training percutaneous transhepatic cholangiography (PTC), i.e. fluoroscopy guidance of needles. The patient's respiration is modelled

Paris-Sud XI, Université de

118

Functionalized expanded porphyrins  

DOEpatents

Disclosed are functionalized expanded porphyrins that can be used as spectrometric sensors for high-valent actinide cations. The disclosed functionalized expanded porphyrins have the advantage over unfunctionalized systems in that they can be immobilized via covalent attachment to a solid support comprising an inorganic or organic polymer or other common substrates. Substrates comprising the disclosed functionalized expanded porphyrins are also disclosed. Further, disclosed are methods of making the disclosed compounds (immobilized and free), methods of using them as sensors to detect high valent actinides, devices that comprise the disclosed compounds, and kits.

Sessler, Jonathan L; Pantos, Patricia J

2013-11-12

119

Surface imaging for patient setup and monitoring for breast radiotherapy  

E-print Network

Approximately one in eight women will get breast cancer at some point in their lives. A promising new treatment is partial breast irradiation, in which multiple radiation beams cross at the tumor site within the patient. ...

Book, Lynn Novella

2007-01-01

120

Recent advances in MRI technology: Implications for image quality and patient safety  

PubMed Central

Recent advances in MRI technology are presented, with emphasis on how this new technology impacts clinical operations (better image quality, faster exam times, and improved throughput). In addition, implications for patient safety are discussed with emphasis on the risk of patient injury due to either high local specific absorption rate (SAR) or large cumulative energy doses delivered during long exam times. Patient comfort issues are examined as well. PMID:23961024

Sobol, Wlad T.

2012-01-01

121

Imaging acute complications in cancer patients: what should be evaluated in the emergency setting?  

PubMed Central

Increased incidence world-wide of cancer and increased survival has also resulted in physicians seeing more complications in patients with cancer. In many cases, complications are the first manifestations of the disease. They may be insidious and develop over a period of months, or acute and manifest within minutes to days. Imaging examinations play an essential role in evaluating cancer and its complications. Plain radiography and ultrasonography (US) are generally performed initially in an urgent situation due to their wide availability, low cost, and minimal or no radiation exposure. However, depending on a patient’s symptoms, evaluation with cross-sectional imaging methods such as computed tomography (CT) and magnetic resonance imaging (MRI) is often necessary. In this review article, we discuss some of the most important acute noninfectious oncological complications for which imaging methods play an essential role in diagnosis. PMID:25609051

2014-01-01

122

Value of magnetic resonance imaging in patients with penile induration (Peyronie's disease).  

PubMed

Magnetic resonance imaging (MRI) is a noninvasive procedure that enables exact imaging of penile anatomy. A total of 34 patients with clinical Peyronie's disease underwent palpation, ultrasound and MRI after intracavernous injection of 10 micrograms. prostaglandin E1. MRI images were obtained before and after intravenous application of gadolinium-diethylenetriaminepentaacetic acid. In 34 patients 45 plaques were palpable. Ultrasound revealed evidence of lesions in 66.6% of the cases. On MRI 36 of 45 palpable plaques (80%) were detected. Not palpable or sonographically revealed indurations could be shown in 4 cases. After intravenous application of gadolinium-diethylenetriaminepentaacetic acid 4 plaques demonstrated contrast enhancement, thus indicating local inflammatory activity. The combination of clinical examination and sonography remains the method of choice for diagnosis and observation of patients with Peyronie's disease. MRI enables exact imaging of penile structures but it does not provide a significant advantage over standard investigative procedures. PMID:7869479

Vosshenrich, R; Schroeder-Printzen, I; Weidner, W; Fischer, U; Funke, M; Ringert, R H

1995-04-01

123

Quantitative cardiac SPECT reconstruction with reduced image degradation due to patient anatomy  

SciTech Connect

Patient anatomy has complicated effects on cardiac SPECT images. The authors investigated reconstruction methods which substantially reduced these effects for improved image quality. A 3D mathematical cardiac-torso (MCAT) phantom which models the anatomical structures in the thorax region were used in the study. The phantom was modified to simulate variations in patient anatomy including regions of natural thinning along the myocardium, body size, diaphragmatic shape, gender, and size and shape of breasts for female patients. Distributions of attenuation coefficients and Tl-201 uptake in different organs in a normal patient were also simulated. Emission projection data were generated from the phantoms including effects of attenuation and detector response. The authors have observed the attenuation-induced artifacts caused by patient anatomy in the conventional FBP reconstructed images. Accurate attenuation compensation using iterative reconstruction algorithms and attenuation maps substantially reduced the image artifacts and improved quantitative accuracy. They conclude that reconstruction methods which accurately compensate for non-uniform attenuation can substantially reduce image degradation caused by variations in patient anatomy in cardiac SPECT.

Tsui, B.M.W.; Zhao, X.D.; Gregoriou, G.K.; Lalush, D.S.; Frey, E.C.; Johnston, R.E.; McCartney, W.H. (Univ. of North Carolina, Chapel Hill, NC (United States))

1994-12-01

124

Expanding the Universe  

NASA Astrophysics Data System (ADS)

Proceedings of the International Conference EXPANDING THE UNIVERSE, On the occasion of the 200th anniversary of the Tartu Observatory, Tartu, Estonia 2011 April 27-29. C. Sterken, L. Leedjarv, E. Tempel (Eds.)

Sterken, Christiaan; Leedjärv, Laurits; Tempel, Elmo

2011-12-01

125

The expandable network disk  

E-print Network

This thesis presents a virtual disk cluster called END, the Expandable Network Disk. END aggregates storage on a cluster of servers into a single virtual disk. END's main goals are to offer good performance during normal ...

Muthitacharoen, Athicha, 1976-

2008-01-01

126

Cardiac electrophysiological activation pattern estimation from images using a patient-specific database of synthetic image sequences.  

PubMed

While abnormal patterns of cardiac electrophysiological activation are at the origin of important cardiovascular diseases (e.g., arrhythmia, asynchrony), the only clinically available method to observe detailed left ventricular endocardial surface activation pattern is through invasive catheter mapping. However, this electrophysiological activation controls the onset of the mechanical contraction; therefore, important information about the electrophysiology could be deduced from the detailed observation of the resulting motion patterns. In this paper, we present the study of this inverse cardiac electrokinematic relationship. The objective is to predict the activation pattern knowing the cardiac motion from the analysis of cardiac image sequences. To achieve this, we propose to create a rich patient-specific database of synthetic time series of the cardiac images using simulations of a personalized cardiac electromechanical model, in order to study this complex relationship between electrical activity and kinematic patterns in the context of this specific patient. We use this database to train a machine-learning algorithm which estimates the depolarization times of each cardiac segment from global and regional kinematic descriptors based on displacements or strains and their derivatives. Finally, we use this learning to estimate the patient’s electrical activation times using the acquired clinical images. Experiments on the inverse electrokinematic learning are demonstrated on synthetic sequences and are evaluated on clinical data with promising results. The error calculated between our prediction and the invasive intracardiac mapping ground truth is relatively small (around 10 ms for ischemic patients and 20 ms for nonischemic patient). This approach suggests the possibility of noninvasive electrophysiological pattern estimation using cardiac motion imaging. PMID:24058008

Prakosa, Adityo; Sermesant, Maxime; Allain, Pascal; Villain, Nicolas; Rinaldi, C Aldo; Rhode, Kawal; Razavi, Reza; Delingette, Hervé; Ayache, Nicholas

2014-02-01

127

Time Dependence of Intrafraction Patient Motion Assessed by Repeat Stereoscopic Imaging  

SciTech Connect

Purpose: To quantify intrafraction patient motion and its time dependence in immobilized intracranial and extracranial patients. The data can be used to optimize the intrafraction imaging frequency and consequent patient setup correction with an image guidance and tracking system, and to establish the required safety margins in the absence of such a system. Method and Materials: The intrafraction motion of 32 intracranial patients, immobilized with a thermoplastic mask, and 11 supine- and 14 prone-treated extracranial spine patients, immobilized with a vacuum bag, were analyzed. The motion was recorded by an X-ray, stereoscopic, image-guidance system. For each group, we calculated separately the systematic (overall mean and SD) and the random displacement as a function of elapsed intrafraction time. Results: The SD of the systematic intrafraction displacements increased linearly over time for all three patient groups. For intracranial-, supine-, and prone-treated patients, the SD increased to 0.8, 1.2, and 2.2 mm, respectively, in a period of 15 min. The random displacements for the prone-treated patients were significantly higher than for the other groups, namely 1.6 mm (1 SD), probably caused by respiratory motion. Conclusions: Despite the applied immobilization devices, patients drift away from their initial position during a treatment fraction. These drifts are in general small if compared with conventional treatment margins, but will significantly contribute to the margin for high-precision radiation treatments with treatment times of 15 min or longer.

Hoogeman, Mischa S. [Department of Radiation Oncology, Erasmus MC - Daniel den Hoed Cancer Center, Rotterdam (Netherlands)], E-mail: m.hoogeman@erasmusmc.nl; Nuyttens, Joost J.; Levendag, Peter C.; Heijmen, Ben J.M. [Department of Radiation Oncology, Erasmus MC - Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

2008-02-01

128

Vessel architectural imaging identifies cancer patient responders to anti-angiogenic therapy.  

PubMed

Measurement of vessel caliber by magnetic resonance imaging (MRI) is a valuable technique for in vivo monitoring of hemodynamic status and vascular development, especially in the brain. Here, we introduce a new paradigm in MRI termed vessel architectural imaging (VAI) that exploits an overlooked temporal shift in the magnetic resonance signal, forming the basis for vessel caliber estimation, and show how this phenomenon can reveal new information on vessel type and function not assessed by any other noninvasive imaging technique. We also show how this biomarker can provide new biological insights into the treatment of patients with cancer. As an example, we demonstrate using VAI that anti-angiogenic therapy can improve microcirculation and oxygen saturation and reduce vessel calibers in patients with recurrent glioblastomas and, more crucially, that patients with these responses have prolonged survival. Thus, VAI has the potential to identify patients who would benefit from therapies. PMID:23955713

Emblem, Kyrre E; Mouridsen, Kim; Bjornerud, Atle; Farrar, Christian T; Jennings, Dominique; Borra, Ronald J H; Wen, Patrick Y; Ivy, Percy; Batchelor, Tracy T; Rosen, Bruce R; Jain, Rakesh K; Sorensen, A Gregory

2013-09-01

129

Diagnostic imaging and risk stratification of patients with acute pulmonary embolism.  

PubMed

Pulmonary embolism (PE) is the third most common acute cardiovascular disease after myocardial infarction and stroke. The prompt diagnosis, risk stratification, and treatment of patients with acute PE can reduce mortality. Multidetector row computed tomography pulmonary angiography (CTPA) is the most common study used to make the diagnosis of acute PE. CTPA may additionally identify right heart dysfunction or alternative diagnoses. There is a growing body of evidence that computed tomography signs of right heart failure predict patients at higher risk of mortality. At the same time, CTPA has about a 6-fold greater whole body effective dose than ventilation-perfusion (V/Q) scintigraphy, and a much higher dose to breast tissue in particular. V/Q scintigraphy should be considered for patients with contraindications to iodinated contrast or for patients with normal chest radiographs, especially young women. Compression ultrasonography of the proximal lower extremities, an imaging study without ionizing radiation, should be considered for patients suspected of acute PE with signs of lower extremity deep venous thrombosis or for patients with negative CTPA or V/Q scan with discordant clinical probability. This article reviews factors affecting the selection of the best imaging test for a particular patient suspected of acute PE, performance characteristics of diagnostic imaging tests, and imaging findings that correlate with higher mortality. PMID:22143281

Burns, Stephanie K; Haramati, Linda B

2012-01-01

130

Value of exercise thallium-201 imaging in patients with diagnostic and nondiagnostic exercise electrocardiograms  

SciTech Connect

The role of exercise imaging with thallium-201 in the evaluation of patients suspected of having coronary artery disease was studied in 194 patients undergoing diagnostic coronary arteriography. Ninety-eight patients had 70 percent or more narrowing of one or more coronary vessels and 96 patients had either no or insignificant coronary artery disease. One hundren twenty-three of the 194 patients had conclusive treadmill exercise electrocardiograms (either positive or negative), and 71 had inconclusive exercise electrocardiograms. The specificity of exercise imaging (97 percent) was higher than that of exercise electrocardiograms (86 percent, p less than 0.02). The specificity of both tests combined was not significantly different from that of exercise electrocardiograms alone. The sensitivity (79 percent) and specificity (95 percent) of exercise imaging were not significantly different in patients with inconclusive exercise electrocardiograms when compared with those in patients whose exercise electrocardiograms were conclusive. These data indicate that exercise imaging is sensitive and specific in diagnosing coronary artery disease in the presence of diagnostic as well as nondiagnostic exercise electrocardiograms and that propranolol therapy does not affect the results.

Iskandrian, A.S.; Segal, B.L.

1981-08-01

131

Clinical review: Lung imaging in acute respiratory distress syndrome patients - an update  

PubMed Central

Over the past 30 years lung imaging has greatly contributed to the current understanding of the pathophysiology and the management of acute respiratory distress syndrome (ARDS). In the past few years, in addition to chest X-ray and lung computed tomography, newer functional lung imaging techniques, such as lung ultrasound, positron emission tomography, electrical impedance tomography and magnetic resonance, have been gaining a role as diagnostic tools to optimize lung assessment and ventilator management in ARDS patients. Here we provide an updated clinical review of lung imaging in ARDS over the past few years to offer an overview of the literature on the available imaging techniques from a clinical perspective. PMID:24238477

2013-01-01

132

Video surveillance of epilepsy patients using color image processing.  

PubMed

This paper introduces a method for tracking patients under video surveillance based on a color marker system. The patients are not restricted in their movements, which requires a tracking system that can overcome non-ideal scenes e.g. occlusions, very fast movements, lighting issues and other moving objects. The suggested marker system consists of twelve unique markers that are located at each joint. By using a color marker system, each marker (if visible) can be found in every frame disregarding the possibility that it was occluded in the previous frame, compared to other tracking systems. PMID:25571054

Bager, Gitte; Vilic, Kenan; Vilic, Adnan; Alving, Jorgen; Wolf, Peter; Sams, Thomas; Sorensen, Helge B D

2014-08-01

133

High-Resolution Imaging of Patients with Bietti Crystalline Dystrophy with CYP4V2 Mutation  

PubMed Central

The purpose of this study was to determine the retinal morphology of eyes with Bietti crystalline dystrophy (BCD) associated with a CYP4V2 mutation using high-resolution imaging techniques. Three subjects with BCD underwent detailed ophthalmic examinations. High-resolution fundus images were obtained with an adaptive optics (AO) fundus camera. A common homozygous mutation was detected in the three patients. Funduscopic examination of the three patients revealed the presence of crystalline deposits in the retina, and all of the crystalline deposits were also detected in the infrared (IR) images. The crystals observed in the IR images were seen as bright reflective plaques located on the RPE layer in the SD-OCT images. The clusters of hyperreflective signals in the AO images corresponded to the crystals in the IR images. High-magnification AO images revealed that the clusters of hyperreflective signals consisted of circular spots that are similar to the signals of cone photoreceptors. Most of these circular spots were detected in healthy areas in the FAF images. There is a possibility that circular spots observed by AO are residual cone photoreceptors located over the crystals. PMID:25276414

Gocho, Kiyoko; Kameya, Shuhei; Akeo, Keiichiro; Kikuchi, Sachiko; Usui, Ayumi; Yamaki, Kunihiko; Hayashi, Takaaki; Tsuneoka, Hiroshi; Mizota, Atsushi; Takahashi, Hiroshi

2014-01-01

134

Dose reduction and image quality optimizations in CT of pediatric and adult patients: phantom studies  

NASA Astrophysics Data System (ADS)

Multi-detector computed tomography (MDCT) can be used to easily and rapidly perform numerous acquisitions, possibly leading to a marked increase in the radiation dose to individual patients. Technical options dedicated to automatically adjusting the acquisition parameters according to the patient's size are of specific interest in pediatric radiology. A constant tube potential reduction can be achieved for adults and children, while maintaining a constant detector energy fluence. To evaluate radiation dose, the weighted CT dose index (CTDIw) was calculated based on the CT dose index (CTDI) measured using an ion chamber, and image noise and image contrast were measured from a scanned image to evaluate image quality. The dose-weighted contrast-to-noise ratio (CNRD) was calculated from the radiation dose, image noise, and image contrast measured from a scanned image. The noise derivative (ND) is a quality index for dose efficiency. X-ray spectra with tube voltages ranging from 80 to 140 kVp were used to compute the average photon energy. Image contrast and the corresponding contrast-to-noise ratio (CNR) were determined for lesions of soft tissue, muscle, bone, and iodine relative to a uniform water background, as the iodine contrast increases at lower energy (i.e., k-edge of iodine is 33 keV closer to the beam energy) using mixed water-iodine contrast normalization (water 0, iodine 25, 100, 200, and 1000 HU, respectively). The proposed values correspond to high quality images and can be reduced if only high-contrast organs are assessed. The potential benefit of lowering the tube voltage is an improved CNRD, resulting in a lower radiation dose and optimization of image quality. Adjusting the tube potential in abdominal CT would be useful in current pediatric radiography, where the choice of X-ray techniques generally takes into account the size of the patient as well as the need to balance the conflicting requirements of diagnostic image quality and radiation dose optimization.

Jeon, P.-H.; Lee, C.-L.; Kim, D.-H.; Lee, Y.-J.; Jeon, S.-S.; Kim, H.-J.

2014-03-01

135

Investigation of Gamma Knife image registration errors resulting from misalignment between the patient and the imaging axis  

SciTech Connect

The ability of Leksell GammaPlan to perform stereotactic space localizations with image sets where there is misalignment of the patient's head (stereotactic frame and fiducial apparatus) relative to the computed tomography (CT) scanner coordinate system was studied. Misalignment is sometimes necessary for patient comfort. Results equally apply to magnetic resonance imaging. Seven 0.5 mm diameter CT-visible spheres were rigidly mounted to a string tied tightly at each end to diagonally opposite posts attached to a Leksell stereotactic frame. A standard CT fiducial box was applied to the frame in the usual clinical manner. A baseline CT scan (1 mm slice thickness) was obtained with the fiducial box perfectly aligned with the scanner axis. After localization of the image set, the (x,y,z) coordinate of the center of each sphere was recorded. Repeat CT scans with varying fiducial box misalignments with the imaging axis were subsequently obtained. The mean difference between the base line and the respective coordinates in misaligned geometries was approximately 0.2 mm ({sigma}=0.2 mm), well within the accuracy of the image sets and the delivery of radiosurgery with the Gamma Knife.

Cernica, George; Wang Zhou; Malhotra, Harish; Boer, Steven de; Podgorsak, Matthew B. [Department of Physics, State University of New York, Buffalo, New York 14260 (United States) and Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States)

2006-04-15

136

High-accuracy patient-to-image registration for the facilitation of image-guided robotic microsurgery on the head.  

PubMed

Image-guided microsurgery requires accuracies an order of magnitude higher than today's navigation systems provide. A critical step toward the achievement of such low-error requirements is a highly accurate and verified patient-to-image registration. With the aim of reducing target registration error to a level that would facilitate the use of image-guided robotic microsurgery on the rigid anatomy of the head, we have developed a semiautomatic fiducial detection technique. Automatic force-controlled localization of fiducials on the patient is achieved through the implementation of a robotic-controlled tactile search within the head of a standard surgical screw. Precise detection of the corresponding fiducials in the image data is realized using an automated model-based matching algorithm on high-resolution, isometric cone beam CT images. Verification of the registration technique on phantoms demonstrated that through the elimination of user variability, clinically relevant target registration errors of approximately 0.1 mm could be achieved. PMID:23340586

Gerber, Nicolas; Gavaghan, Kate A; Bell, Brett J; Williamson, Tom M; Weisstanner, Christian; Caversaccio, Marco-Domenico; Weber, Stefan

2013-04-01

137

Reliable and robust transmission and storage techniques for medical images with patient information.  

PubMed

There is an increased emphasis on the use of digital techniques in all aspects of human life today. Broadcast radio and television, cellular phone services, consumer and entertainment electronics etc are increasingly using digital signal processing techniques to improve the quality of service. Transmission and storage of documentation and images pertaining to patient records cannot remain an exception to this global trend. Hence, patient records (text and image information) are increasingly stored and processed in digital form. Currently, text and image information, which constitute two separate pieces of data are handled as different files. Thus, there is a possibility of the text and message information, pertaining to different patients, being interchanged and thus mishandled. This can be avoided by merging text and image information in such a manner that the two can be separated without perceptible damage to information contained in either file. Digital watermarking techniques can be used to interleave patient information with medical images. In this work, we have employed digital watermarking along with strong cryptographic protocols and powerful error correcting codes. This reduces the probability of sensitive patient information falling into the wrong hands and ensures information integrity when it is conveyed over noisy channels. PMID:20703594

Nergui, Myagmarbayar; Acharya, U Sripati; Acharya U, Rajendra; Yu, Wenwei

2010-12-01

138

Improved Late Gadolinium Enhancement MR Imaging for Patients with Implanted Cardiac Devices  

PubMed Central

Purpose To propose and test a modified wideband late gadolinium enhancement (LGE) magnetic resonance (MR) imaging technique to overcome hyperintensity image artifacts caused by implanted cardiac devices. Materials and Methods Written informed consent was obtained from all participants, and the HIPAA-compliant study protocol was approved by the institutional review board. Studies in phantoms and in a healthy volunteer were performed to test the hypothesis that the hyperintensity artifacts that are typically observed on LGE images in patients with implanted cardiac devices are caused by insufficient inversion of the affected myocardial signal. The conventional LGE MR imaging pulse sequence was modified by replacing the nonselective inversion pulse with a wideband inversion pulse. The modified LGE sequence, along with the conventional LGE sequence, was evaluated in 12 patients with implantable cardioverter defibrillators (ICDs) who were referred for cardiac MR imaging. Results The ICD causes 2–6 kHz in frequency shift at locations 5–10 cm away from the device. This off-resonance falls outside the typical spectral bandwidth of the nonselective inversion pulse used in conventional LGE, which results in the hyperintensity artifact. In 10 of the 12 patients, the conventional LGE technique produced severe, uninterpretable hyperintensity artifacts in the anterior and lateral portions of the left ventricular wall. These artifacts were eliminated with use of the wideband LGE sequence, thereby enabling confident evaluation of myocardial viability. Conclusion The modified wideband LGE MR imaging technique eliminates the hyperintensity artifacts seen in patients with cardiac devices. The technique may enable LGE MR imaging in patients with cardiac devices, in whom LGE MR imaging otherwise could not be used for diagnosis. © RSNA, 2013 Online supplemental material is available for this article. PMID:24086074

Rashid, Shams; Rapacchi, Stanislas; Vaseghi, Marmar; Tung, Roderick; Shivkumar, Kalyanam; Finn, J. Paul

2014-01-01

139

An optically stimulated luminescence dosimeter for measuring patient exposure from imaging guidance procedures  

NASA Astrophysics Data System (ADS)

There is a growing interest in patient exposure resulting from an x-ray imaging procedure used in image-guided radiation therapy. This study explores a feasibility to use a commercially available optically stimulated luminescence (OSL) dosimeter, nanoDot, for estimating imaging radiation exposure to patients. The kilovoltage x-ray sources used for kV-cone-beam CT (CBCT) imaging acquisition procedures were from a Varian on-board imager (OBI) image system. An ionization chamber was used to determine the energy response of nanoDot dosimeters. The chamber calibration factors for x-ray beam quality specified by half-value layer were obtained from an Accredited Dosimetry Calibration Laboratory. The Monte Carlo calculated dose distributions were used to validate the dose distributions measured by using the nanoDot dosimeters in phantom and in vivo. The range of the energy correction factors for the nanoDot as a function of photon energy and bow-tie filters was found to be 0.88-1.13 for different kVp and bow-tie filters. Measurement uncertainties of nanoDot were approximately 2-4% after applying the energy correction factors. The tests of nanoDot placed on a RANDO phantom and on patient's skin showed consistent results. The nanoDot is suitable dosimeter for in vivo dosimetry due to its small size and manageable energy dependence. The dosimeter placed on a patient's skin has potential to serve as an experimental method to monitor and to estimate patient exposure resulting from a kilovoltage x-ray imaging procedure. Due to its large variation in energy response, nanoDot is not suitable to measure radiation doses resulting from mixed beams of megavoltage therapeutic and kilovoltage imaging radiations.

Ding, George X.; Malcolm, Arnold W.

2013-09-01

140

Computer-extracted MR imaging features are associated with survival in glioblastoma patients.  

PubMed

Automatic survival prognosis in glioblastoma (GBM) could result in improved treatment planning for the patient. The purpose of this research is to investigate the association of survival in GBM patients with tumor features in pre-operative magnetic resonance (MR) images assessed using a fully automatic computer algorithm. MR imaging data for 68 patients from two US institutions were used in this study. The images were obtained from the Cancer Imaging Archive. A fully automatic computer vision algorithm was applied to segment the images and extract eight imaging features from the MRI studies. The features included tumor side, proportion of enhancing tumor, proportion of necrosis, T1/FLAIR ratio, major axis length, minor axis length, tumor volume, and thickness of enhancing margin. We constructed a multivariate Cox proportional hazards regression model and used a likelihood ratio test to establish whether the imaging features are prognostic of survival. We also evaluated the individual prognostic value of each feature through multivariate analysis using the multivariate Cox model and univariate analysis using univariate Cox models for each feature. We found that the automatically extracted imaging features were predictive of survival (p = 0.031). Multivariate analysis of individual features showed that two individual features were predictive of survival: proportion of enhancing tumor (p = 0.013), and major axis length (p = 0.026). Univariate analysis indicated the same two features as significant (p = 0.021, and p = 0.017 respectively). We conclude that computer-extracted MR imaging features can be used for survival prognosis in GBM patients. PMID:25151504

Mazurowski, Maciej A; Zhang, Jing; Peters, Katherine B; Hobbs, Hasan

2014-12-01

141

Imaging changes in neural circuits in patients with depression using 1H-magnetic resonance spectroscopy and diffusion tensor imaging?  

PubMed Central

1H-magnetic resonance spectroscopy imaging and diffusion tensor imaging were performed in 19 patients with mild depression and in 13 controls. The mean age of the patients was 31 years. The mean Hamilton depression score of the patients was 22.5 ± 13.2. N-acetylaspartate, choline and creatine concentrations and the average diffusion coefficient and fractional anisotropy values were measured in the bilateral hippocampus, striatum, thalamus and prefrontal deep white matter. Compared with the control group, the mild depressed patients had: (1) a higher choline/creatine ratio and a negative correlation between the choline/creatine ratio and the average diffusion coefficient in the hippocampus; (2) a lower choline/creatine ratio and a higher fractional anisotropy in the striatum; (3) a lower fractional anisotropy and a positive correlation between the fractional anisotropy and the choline/creatine ratio in the prefrontal deep white matter; and (4) a higher average diffusion coefficient and a positive correlation between the choline/creatine ratio and the N-acetylaspartate/creatine ratio in the thalamus, as well as positive correlation between the choline/creatine ratio and Hamilton depression scores. These data suggest evidence of abnormal connectivity in neurofibrotic microstructures and abnormal metabolic alterations in the limbic-cortical-striatal-pallidal-thalamic neural circuit in patients with mild depression.

Chen, Shaoqiong; Lai, Lisha; Kang, Zhuang; Luo, Xiao; Zhang, Jiansheng; Li, Jianfang

2012-01-01

142

Expanding perfusion across disciplines: the use of thrombelastography technology to reduce risk in an obstetrics patient with Gray Platelet Syndrome--a case study.  

PubMed

It is important that our speciality continues to push its boundaries. Our perfusion team has invested time lecturing to non-cardiac specialties about perfusion-led technology. This resulted in working closely with the obstetrics team to treat a pregnant patient with the bleeding disorder Gray Platelet Syndrome. In the first instance, we used our Thromboelastograph (TEG) platelet mapping programme to assess the patient. These results agreed with the platelet aggregation tests, showing a degree of platelet inhibition, but it was the overall clotting profile (basic thrombelastograph), showing a borderline hyper-coagulable state, that was of most interest and commonly seen in pregnancy. We believe a TEG result within acceptable limits could help re-adjust the risk of spinal haematomas following regional anaesthesia, thereby, reducing the risks of difficult intubation and general anaesthetic exposure to the baby. The case study describes both basic and platelet mapping thrombelastographs and their potential role in not only this patient with Gray Platelet Syndrome, but any obstetric patient where there are bleeding concerns. PMID:21227981

Clements, Ann; Jindal, Sucheta; Morris, Chris; Srivastava, Garima; Ikomi, Amaju; Mulholland, John

2011-05-01

143

Influence of exposure parameters on patient dose and image noise in computed tomography  

NASA Astrophysics Data System (ADS)

This work presents the results of investigation of influence of main exposure parameters on the patient dose and image noise on five clinical computed tomography units. Patient dose was determined by means of the quantity CTDIair free on air measured with pencil shaped ionization chamber. The image noise was estimated as a standard deviation of CT numbers in a 500 mm2 central region of interest in a water-equivalent phantom positioned in the centre of rotation. The alteration of tube voltage and tube current show the potential in patient dose reduction up to 40% but may deteriorate image quality and has to be carefully applied in order to optimize the clinical CT protocols taking into account the specific clinical task. This survey is essential for optimization of routine CT protocols especially for CT units without automatic exposure control systems, which are main part of CT units in Bulgaria.

Stoyanov, Desislav; Vassileva, Jenia

2009-01-01

144

Clinical assessment and magnetic resonance imaging of the shoulder of patients with spinal cord injury  

PubMed Central

Objective To study the shoulder of this group of patients using magnetic resonance imaging to detect clinical and subclinical disorders and establish a rehabilitation program. Methods Nine patients with spinal cord injury followed in the Laboratory of Biomechanics and Rehabilitation of the Locomotive System at HC/UNICAMP were divided into two groups according to the presence of paraplegia and tetraplegia and were clinically assessed for correlation with the imaging exams. Results Normal results were found in 41% of the shoulders. Most common injuries were tendinopathy of the supraspinatus and acromioclavicular joint degeneration. Eighty percent of injured shoulders had combined lesions. Conclusion A great variety of causes of shoulder pain was identified in paraplegic and tetraplegic subjects. Routine clinical assessment and imaging studies of the shoulder may contribute to the evolution of rehabilitation and reduction of pain and musculoskeletal disorders. Level of Evidence II, Development of Diagnostic Criteria on Consecutive Patients, With Universally Applied Reference "Gold" Standard. PMID:24453620

Alves, Alex Pereira; Terrabuio Junior, Alberto Antonio; Pimenta, Ciro Jabur; Medina, Giovanna Ignácio Subirá; Rimkus, Carolina de Medeiros; Cliquet Júnior, Alberto

2012-01-01

145

Results of stereotactic radiosurgery for patients with imaging defined cavernous sinus meningiomas  

SciTech Connect

Introduction: The purpose of this study was to evaluate the efficacy and safety of stereotactic radiosurgery as primary management for patients with imaging defined cavernous sinus meningiomas. Methods: Between 1992 and 2001, 49 patients had radiosurgery for dural-based masses of the cavernous sinus presumed to be meningiomas. The mean patient age was 55.5 years. The mean tumor volume was 10.2 mL; the mean tumor margin dose was 15.9 Gy. The mean follow-up was 58 months (range, 16-144 months). Results: No tumor enlarged after radiosurgery. Twelve of 38 patients (26%) with preexisting diplopia or facial numbness/pain had improvement in cranial nerve function. Five patients (10%) had new (n = 3) or worsened (n = 2) trigeminal dysfunction; 2 of these patients (4%) underwent surgery at 20 and 25 months after radiosurgery despite no evidence of tumor progression. Neither patient improved after partial tumor resection. One patient (2%) developed an oculomotor nerve injury. One patient (2%) had an ischemic stroke related to occlusion of the cavernous segment of the internal carotid artery. Event-free survival was 98%, 85%, and 80% at 1, 3, and 7 years after radiosurgery, respectively. Univariate analysis of patient and dosimetric factors found no analyzed factor correlated with postradiosurgical morbidity. Conclusions: Radiosurgery was an effective primary management strategy for patients with an imaging defined cavernous sinus meningioma. Except in situations of symptomatic mass effect, unusual clinical presentation, or atypical imaging features, surgery to confirm the histologic diagnosis is unlikely to provide clinical benefit.

Pollock, Bruce E. [Department of Neurological Surgery, Mayo Clinic College of Medicine, Rochester, MN (United States) and Division of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States)]. E-mail: pollock.bruce@mayo.edu; Stafford, Scott L. [Division of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, MN (United States)

2005-08-01

146

Imaging of the small bowel: Crohn’s disease in paediatric patients  

PubMed Central

In more than 20% of all patients, the Crohn’s disease presents before the age of 18years. The diagnosis and management of Crohn’s disease in children has changed dramatically over the last decade, mainly due to increased awareness, availability of newer diagnostic modalities such as magnetic resonance imaging (MRI) and newer, more powerful treatments such as biologics. Imaging of the small bowel is needed for diagnosis, management, follow-up and also evaluation of the disease in terms of location, extent, activity and complications. We review all the methods (barium examinations, ultrasonography, computed tomography, MR, and computed tomography- positron emission tomography) commonly used for imaging the small bowel in paediatric patients with Crohn’s disease analyzing the advantages and disadvantages of each modality, with particular emphasis on MR imaging. PMID:24976933

Casciani, Emanuele; De Vincentiis, Chiara; Polettini, Elisabetta; Masselli, Gabriele; Di Nardo, Giovanni; Civitelli, Fortunata; Cucchiara, Salvatore; Gualdi, Gian Franco

2014-01-01

147

Image-Based Electronic Patient Records for Secured Collaborative Medical Applications  

Microsoft Academic Search

We developed a Web-based system to interactively display image-based electronic patient records (EPR) for secured intranet and Internet collaborative medical applications. The system consists of four major components: EPR DICOM gateway (EPR-GW), image-based EPR repository server (EPR-Server), Web server and EPR DICOM viewer (EPR-Viewer). In the EPR-GW and EPR-Viewer, the security modules of digital signature and authentication are integrated to

Jianguo Zhang; Jianyong Sun; Yuanyuan Yang; Chenwen Liang; Yihong Yao; Jin Jin; Weihua Cai; Kun Sun; Guozhen Zhang

2005-01-01

148

N-isopropyl-p-(I-123)iodoamphetamine lung imaging in a patient with chronic pulmonary thromboembolism  

SciTech Connect

A patient with a brain infarct was found to have chronic pulmonary embolism associated with perfusion defects on blood flow imaging with N-isopropyl-p-(I-123)iodoamphetamine (I-123 IMP). However, gradually increasing uptake of I-123 IMP was seen in later images, in areas distal to the embolus. The increased uptake to the embolized lung seemed to be through the systemic collateral circulation.

Kosuda, S.; Kawahara, S.; Tamura, K.; Ishikawa, N.; Ono, A.; Kubo, A.; Hashimoto, S. (Okura National Hospital, Tokyo (Japan))

1989-10-01

149

Protection of patients in diagnostic and interventional medical imaging: collaboration is the key.  

PubMed

The radiology community (medical physicists, radiologic technologists, radiologists, and interventional proceduralists) has led the educational and awareness efforts in the medical arena to reduce radiation dose to patients through effective collaborations that bridge traditional medical specialty silos to reach health worker stakeholders. These successful collaborations have also included both vendors and regulators, with the overarching goal of radiation protection of patients (justification, optimization, and use of dose reference levels). This focus on patients often raises overall safety awareness and lowers occupational radiation doses as well. It is critical that the entire radiology community continue to act as leaders in these radiation safety efforts for both employees and patients. In order to be successful, it is important to understand safety culture and the growing, worldwide, multimedia resources that are available. There is little time or budget to recreate or duplicate training materials or risk communication information that may already exist. Together with the increasingly fast-paced and demanding healthcare environment and sharp focus on quality, it has never been more important to understand how to achieve better quality care for radiology departments. It is also important to measure and report quality for many customers, including patients, referring providers, and many other stakeholders. This short report will briefly define safety culture and describe methods for using collective learning tools that document radiation protection of patients in diagnostic and interventional imaging. These tools include the use of imaging modality registries, such as the Computed Tomography Does Index Registry, peer review of imaging reports, the use of clinical decision support, and guidelines. Finally, the Image Gently and Image Wisely campaigns provide examples of cross-disciplinary collaboration to improve radiation protection of patients. PMID:25551505

Applegate, Kimberly E

2015-02-01

150

Prospective Imaging Biomarker Assessment of Mortality Risk in Patients Treated with Head and Neck Radiotherapy  

PubMed Central

Purpose The optimal roles for imaging-based biomarkers in the management of head and neck cancer remain undefined. Unresolved questions include whether functional or anatomic imaging biomarkers might improve mortality risk assessment for this disease. We addressed these issues in a prospective institutional trial. Methods and Materials Ninety-eight patients with locally advanced pharyngolaryngeal squamous cell cancer were enrolled. Each underwent pre-and post-chemoradiotherapy contrast-enhanced CT and FDG-PET/CT imaging. Imaging parameters were correlated with survival outcomes. Results Low post-radiation primary tumor FDG avidity correlated with improved survival on multivariate analysis; so too did complete primary tumor response by CT alone. Although both imaging modalities lacked sensitivity, each had high specificity and negative predictive value for disease-specific mortality risk assessment. Kaplan-Meier estimates confirmed that both CT and FDG-PET/CT stratify patients into distinct high- and low-probability survivorship groups on the basis of primary tumor response to radiotherapy. Subset analyses demonstrated that the prognostic value for each biomarker was primarily derived from patients at high risk for local treatment failure (HPV-negative disease, non-oropharyngeal primary disease, or tobacco use). Conclusions CT- and FDG-PET/CT-based biomarkers are useful clinical tools in head and neck cancer-specific mortality risk assessment following radiotherapy, particularly for high-risk HPV-unrelated disease. Focus should be placed on further refinement and corroboration of imaging-based biomarkers in future studies. PMID:20171802

Moeller, Benjamin J.; Rana, Vishal; Cannon, Blake A.; Williams, Michelle D.; Sturgis, Erich M.; Ginsberg, Lawrence E.; Macapinlac, Homer A.; Lee, J. Jack; Ang, K. Kian; Chao, K.S. Clifford; Chronowski, Gregory M.; Frank, Steven J.; Morrison, William H.; Rosenthal, David I.; Weber, Randal S.; Garden, Adam S.; Lippman, Scott M.; Schwartz, David L.

2010-01-01

151

Contrast-Enhanced MR Imaging of Lymph Nodes in Cancer Patients  

PubMed Central

The accurate identification and characterization of lymph nodes by modern imaging modalities has important therapeutic and prognostic significance for patients with newly diagnosed cancers. The presence of nodal metastases limits the therapeutic options, and it generally indicates a worse prognosis for the patients with nodal metastases. Yet anatomic imaging (CT and MR imaging) is of limited value for depicting small metastatic deposits in normal-sized nodes, and nodal size is a poor criterion when there is no extracapsular extension or focal nodal necrosis to rely on for diagnosing nodal metastases. Thus, there is a need for functional methods that can be reliably used to identify small metastases. Contrast-enhanced MR imaging of lymph nodes is a non-invasive method for the analysis of the lymphatic system after the interstitial or intravenous administration of contrast media. Moreover, some lymphotrophic contrast media have been developed and used for detecting lymph node metastases, and this detection is independent of the nodal size. This article will review the basic principles, the imaging protocols, the interpretation and the accuracies of contrast-enhanced MR imaging of lymph nodes in patients with malignancies, and we also focus on the recent issues cited in the literature. In addition, we discuss the results of several pre-clinical studies and animal studies that were conducted in our institution. PMID:20592922

Choi, Seung Hong

2010-01-01

152

Optimization of diagnostic imaging use in patients with acute abdominal pain (OPTIMA): Design and rationale  

PubMed Central

Background The acute abdomen is a frequent entity at the Emergency Department (ED), which usually needs rapid and accurate diagnostic work-up. Diagnostic work-up with imaging can consist of plain X-ray, ultrasonography (US), computed tomography (CT) and even diagnostic laparoscopy. However, no evidence-based guidelines exist in current literature. The actual diagnostic work-up of a patient with acute abdominal pain presenting to the ED varies greatly between hospitals and physicians. The OPTIMA study was designed to provide the evidence base for constructing an optimal diagnostic imaging guideline for patients with acute abdominal pain at the ED. Methods/design Thousand consecutive patients with abdominal pain > 2 hours and < 5 days will be enrolled in this multicentre trial. After clinical history, physical and laboratory examination all patients will undergo a diagnostic imaging protocol, consisting of plain X-ray (upright chest and supine abdomen), US and CT. The reference standard will be a post hoc assignment of the final diagnosis by an expert panel. The focus of the analysis will be on the added value of the imaging modalities over history and clinical examination, relative to the incremental costs. Discussion This study aims to provide the evidence base for the development of a diagnostic algorithm that can act as a guideline for ED physicians to evaluate patients with acute abdominal pain. PMID:17683592

Laméris, Wytze; van Randen, Adrienne; Dijkgraaf, Marcel GW; Bossuyt, Patrick MM; Stoker, Jaap; Boermeester, Marja A

2007-01-01

153

Digital imaging and electronic patient records in pathology using an integrated department information system with PACS.  

PubMed

Picture archiving and communication systems have been widely used in radiology thus far. Owing to the progress made in digital photo technology, their use in medicine opens up further opportunities. In the field of pathology, digital imaging offers new possiblities for the documentation of macroscopic and microscopic findings. Digital imaging has the advantage that the data is permanently and readily available, independent of conventional archives. In the past, PACS was a separate entity. Meanwhile, however, PACS has been integrated in DIS, the department information system, which was also run separately in former times. The combination of these two systems makes the administration of patient data, findings and images easier. Moreover, thanks to the introduction of special communication standards, a data exchange between different department information systems and hospital information systems (HIS) is possible. This provides the basis for a communication platform in medicine, constituting an electronic patient record (EPR) that permits an interdisciplinary treatment of patients by providing data of findings and images from clinics treating the same patient. As the pathologic diagnosis represents a central and often therapy-determining component, it is of utmost importance to add pathologic diagnoses to the EPR. Furthermore, the pathologist's work is considerably facilitated when he is able to retrieve additional data from the patient file. In this article, we describe our experience gained with the combined PACS and DIS systems recently installed at the Department of Pathology, University of Magdeburg. Moreover, we evaluate the current situation and future prospects for PACS in pathology. PMID:12498223

Kalinski, Thomas; Hofmann, Harald; Franke, Dagmar-Sybilla; Roessner, Albert

2002-01-01

154

Brain magnetic resonance imaging screening is not useful for HIV-1-infected patients without neurological symptoms.  

PubMed

We investigated the diagnostic usefulness of brain magnetic resonance imaging (MRI) screening in HIV-1-infected patients without neurological symptoms in detecting intracranial diseases at early stages. In this retrospective analysis, the study patients were HIV-1-infected patients who underwent brain MRI scan in clinical practice between 2001 and 2013. We excluded patients with MRI for (1) follow-up examination for prediagnosed intracranial diseases, (2) cancer staging, (3) screening mycobacterium/bacteria/fungi disease proliferation in the brain, and (4) evaluation for meningitis/encephalitis. The study patients (n=485) were classified into two groups: those who underwent brain MRI scan without any neurological symptoms/signs (asymptomatic patients, n=158) and those who underwent MRI due to such symptoms (symptomatic patients, n=327). Asymptomatic patients had lower CD4 counts than symptomatic patients (median 78 versus 241/?l). Intracranial diseases were detected in three (2%) of the asymptomatic patients [two toxoplasmosis and one progressive multifocal leukoencephalopathy (PML)] compared to 58 (19%) of the symptomatic patients (the ?(2) test, p<0.01). The latter included toxoplasmosis (n=10), PML (n=7), cytomegalovirus encephalitis (n=3), primary central nervous system lymphoma (n=3), cryptococcoma/meningitis (n=3), and HIV-associated dementia (n=17). Among symptomatic patients, intracranial diseases were common in those with slurred speech (3/6, 50%), seizure (4/10, 40%), eyesight/vision abnormality (5/16, 31%), altered mental status (8/31, 26%), and hemiplegia/numbness (13/50, 26%). For patients with CD4 count <200/?l, intracranial diseases were detected in only 3 (3%) of 144 asymptomatic patients, compared with 46 (32%) of 113 symptomatic patients (p<0.01). Brain MRI screening for HIV-1-infected patients without neurological symptoms is of little value. PMID:25084148

Nishijima, Takeshi; Gatanaga, Hiroyuki; Teruya, Katsuji; Tajima, Tsuyoshi; Kikuchi, Yoshimi; Hasuo, Kanehiro; Oka, Shinichi

2014-10-01

155

Pain and disability correlated with disc degeneration via magnetic resonance imaging in scoliosis patients  

PubMed Central

Prior imaging studies of scoliosis patients attempted to demonstrate a relationship between plain radiographic curve patterns and curve progression and pain, or used magnetic resonance imaging (MRI) to focus on spinal cord abnormalities. Pain in scoliosis patients may differ from nondeformity patients, yet may still be discogenic. The purpose of this study was to assess the possible relationship of degenerative disc findings on MRI to scoliosis patients’ pain. This prospective study enrolled scoliosis and control patients, all of whom had assessment for back pain (visual analog scale) and disability (Oswestry Index) and spinal MRI to identify prevalence and distribution of degenerative disc findings. Specifically, we assessed 60 consecutive pediatric and adult idiopathic scoliosis patients who had progressed to surgical treatment, 60 age- and gender-matched asymptomatic controls, and 172 nondeformity symptomatic degenerative disc disease patients who had progressed to surgical treatment. All subjects had independent analysis of their preoperative MRI for disc degeneration, disc herniation, Schmorl’s nodes, and inflammatory end plate changes. Imaging findings of the scoliosis patients were compared to those from asymptomatic and symptomatic control groups. Our results found that both pediatric and adult scoliosis patients had significantly more pain and disability than did asymptomatic controls (P < 0.001). The adult idiopathic scoliosis patients had pain and disability similar to those of surgical degenerative disc disease control groups. Disc degeneration and herniation (contained) were not related to pain. However, in the pediatric scoliosis patients, those with Schmorl’s nodes often had greater pain than those without (P = 0.01). Adults with painful scoliosis, typically occurring at the apex of the scoliosis or at the lumbosacral junction, had a significantly higher frequency of inflammatory end plate changes on MRI than did controls (P < 0.001). Prior studies have demonstrated a correlation of inflammatory end plate changes to lumbar discogenic pain. In conclusions, scoliosis patients who have progressed to surgical intervention, pediatric patients have varying degrees of pain, and those with Schmorl’s nodes may be at greater risk for pain. Adult scoliosis patients have multifactorial pain of which one component may be related to degeneration of the lower lumbar discs similar to that in nondeformity patients. Additionally, adult scoliosis patients may have MRI findings consistent with discogenic pain at the apex of their curvature, most commonly at the proximal lumbar levels. PMID:17973128

Mullin, William J.

2007-01-01

156

Sociodemographic and Disease Correlates of Body Image Distress among Patients with Systemic Sclerosis  

Microsoft Academic Search

BackgroundBody image concerns are infrequently studied in systemic sclerosis (SSc), even though significant visible disfigurement is common. The objective of this study was to identify sociodemographic and disease-related correlates of dissatisfaction with appearance and social discomfort among people with SSc.MethodsSSc patients came from the 15-center Canadian Scleroderma Research Group Registry. Sociodemographic information was based on patient self-report. Disease characteristics were

Lisa R. Jewett; Marie Hudson; Vanessa L. Malcarne; Murray Baron; Brett D. Thombs

2012-01-01

157

Diffusion-Weighted Imaging of White Matter Abnormalities in Patients with Phenylketonuria  

Microsoft Academic Search

Summary: Phenylketonuria (PKU) is an autosomal reces- sive disorder caused by a deficiency of the enzyme phenyl- alanine hydroxylase (EC 1.14.16.1). Affected patients de- velop elevated plasma and tissue levels of phenylalanine and its related ketoacids. Untreated patients usually exhibit severe mental retardation and poor motor function, with characteristic T2 white matter signal abnormalities on con- ventional MR images. In

Micheal D. Phillips; Peter McGraw; Mark J. Lowe; Vincent P. Mathews; Bryan E. Hainline

2001-01-01

158

Accurate positioning for head and neck cancer patients using 2D and 3D image guidance.  

PubMed

Our goal is to determine an optimized image-guided setup by comparing setup errors determined by two-dimensional (2D) and three-dimensional (3D) image guidance for head and neck cancer (HNC) patients immobilized by customized thermoplastic masks. Nine patients received weekly imaging sessions, for a total of 54, throughout treatment. Patients were first set up by matching lasers to surface marks (initial) and then translationally corrected using manual registration of orthogonal kilovoltage (kV) radiographs with DRRs (2D-2D) on bony anatomy. A kV cone beam CT (kVCBCT) was acquired and manually registered to the simulation CT using only translations (3D-3D) on the same bony anatomy to determine further translational corrections. After treatment, a second set of kVCBCT was acquired to assess intrafractional motion. Averaged over all sessions, 2D-2D registration led to translational corrections from initial setup of 3.5 ± 2.2 (range 0-8) mm. The addition of 3D-3D registration resulted in only small incremental adjustment (0.8 ± 1.5 mm). We retrospectively calculated patient setup rotation errors using an automatic rigid-body algorithm with 6 degrees of freedom (DoF) on regions of interest (ROI) of in-field bony anatomy (mainly the C2 vertebral body). Small rotations were determined for most of the imaging sessions; however, occasionally rotations > 3° were observed. The calculated intrafractional motion with automatic registration was < 3.5 mm for eight patients, and < 2° for all patients. We conclude that daily manual 2D-2D registration on radiographs reduces positioning errors for mask-immobilized HNC patients in most cases, and is easily implemented. 3D-3D registration adds little improvement over 2D-2D registration without correcting rotational errors. We also conclude that thermoplastic masks are effective for patient immobilization. PMID:21330971

Kang, Hyejoo; Lovelock, Dale M; Yorke, Ellen D; Kriminski, Sergey; Lee, Nancy; Amols, Howard I

2011-01-01

159

Accurate positioning for head and neck cancer patients using 2D and 3D image guidance  

PubMed Central

Our goal is to determine an optimized image-guided setup by comparing setup errors determined by two-dimensional (2D) and three-dimensional (3D) image guidance for head and neck cancer (HNC) patients immobilized by customized thermoplastic masks. Nine patients received weekly imaging sessions, for a total of 54, throughout treatment. Patients were first set up by matching lasers to surface marks (initial) and then translationally corrected using manual registration of orthogonal kilovoltage (kV) radiographs with DRRs (2D-2D) on bony anatomy. A kV cone beam CT (kVCBCT) was acquired and manually registered to the simulation CT using only translations (3D-3D) on the same bony anatomy to determine further translational corrections. After treatment, a second set of kVCBCT was acquired to assess intrafractional motion. Averaged over all sessions, 2D-2D registration led to translational corrections from initial setup of 3.5 ± 2.2 (range 0–8) mm. The addition of 3D-3D registration resulted in only small incremental adjustment (0.8 ± 1.5 mm). We retrospectively calculated patient setup rotation errors using an automatic rigid-body algorithm with 6 degrees of freedom (DoF) on regions of interest (ROI) of in-field bony anatomy (mainly the C2 vertebral body). Small rotations were determined for most of the imaging sessions; however, occasionally rotations > 3° were observed. The calculated intrafractional motion with automatic registration was < 3.5 mm for eight patients, and < 2° for all patients. We conclude that daily manual 2D-2D registration on radiographs reduces positioning errors for mask-immobilized HNC patients in most cases, and is easily implemented. 3D-3D registration adds little improvement over 2D-2D registration without correcting rotational errors. We also conclude that thermoplastic masks are effective for patient immobilization. PMID:21330971

Kang, Hyejoo; Lovelock, Dale M.; Yorke, Ellen D.; Kriminiski, Sergey; Lee, Nancy; Amols, Howard I.

2011-01-01

160

Deformable image registration for geometrical evaluation of DIBH radiotherapy treatment of lung cancer patients  

NASA Astrophysics Data System (ADS)

Respiration and anatomical variation during radiotherapy (RT) of lung cancer yield dosimetric uncertainties of the delivered dose, possibly affecting the clinical outcome if not corrected for. Adaptive radiotherapy (ART), based on deformable image registration (DIR) and Deep-Inspiration-Breath-Hold (DIBH) gating can potentially improve the accuracy of RT. Purpose: The objective was to investigate the performance of contour propagation on repeated CT and Cone Beam CT (CBCT) images in DIBH compared to images acquired in free breathing (FB), using a recently released DIR software. Method: Three locally advanced non-small cell lung cancer patients were included, each with a planning-, midterm- and final CT (pCT, mCT, fCT) and 7 CBCTs acquired weekly and on the same day as the mCT and fCT. All imaging were performed in both FB and DIBH, using Varian RPM system for respiratory tracking. Delineations of anatomical structures were performed on each image set. The CT images were retrospective rigidly and deformable registered to all obtained images using the Varian Smart Adapt v. 11.0. The registered images were analysed for volume change and Dice Similarity Coefficient (DSC). Result: Geometrical similarities were found between propagated and manually delineated structures, with a slightly favour of FB imaging. Special notice should be taken to registrations where image artefacts or low tissue contrast are present. Conclusion: This study does not support the hypothesis that DIBH images perform better image registration than FB images. However DIR is a feasible tool for ART of lung cancer.

Ottosson, W.; Lykkegaard Andersen, J. A.; Borrisova, S.; Mellemgaard, A.; Behrens, C. F.

2014-03-01

161

Grazing incidence beam expander  

Microsoft Academic Search

A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be

P. R. Akkapeddi; P. Glenn; A. Fuschetto; Q. Appert; V. K. Viswanathan

1985-01-01

162

Magnetic Resonance Imaging in Multiple Sclerosis – Patients' Experiences, Information Interests and Responses to an Education Programme  

PubMed Central

Background Magnetic resonance imaging (MRI) is a key diagnostic and monitoring tool in multiple sclerosis (MS) management. However, many scientific uncertainties, especially concerning correlates to impairment and prognosis remain. Little is known about MS patients' experiences, knowledge, attitudes, and unmet information needs concerning MRI. Methods We performed qualitative interviews (n?=?5) and a survey (n?=?104) with MS patients regarding MRI patient information, and basic MRI knowledge. Based on these findings an interactive training program of 2 hours was developed and piloted in n?=?26 patients. Results Interview analyses showed that patients often feel lost in the MRI scanner and left alone with MRI results and images while 90% of patients in the survey expressed a high interest in MRI education. Knowledge on MRI issues was fair with some important knowledge gaps. Major information interests were relevance of lesions as well as the prognostic and diagnostic value of MRI results. The education program was highly appreciated and resulted in a substantial knowledge increase. Patients reported that, based on the program, they felt more competent to engage in encounters with their physicians. Conclusion This work strongly supports the further development of an evidence-based MRI education program for MS patients to enhance participation in health-care. PMID:25415501

Brand, Judith; Köpke, Sascha; Kasper, Jürgen; Rahn, Anne; Backhus, Imke; Poettgen, Jana; Stellmann, Jan-Patrick; Siemonsen, Susanne; Heesen, Christoph

2014-01-01

163

BodyWise: Evaluating a Pilot Body Image Group for Patients with Anorexia Nervosa.  

PubMed

Body image disturbance can be enduring and distressing to individuals with eating disorders and effective treatments remain limited. This pilot study evaluated a group-based treatment-BodyWise-developed for use in full and partial hospitalization with patients with anorexia nervosa at low weight. A partial crossover waitlist design was used. BodyWise (N?=?50) versus treatment as usual (N?=?40) were compared on standardized measures of body image disturbance. Results demonstrated significant improvement in the group compared to treatment as usual for the primary outcome measure (Eating Disorder Examination-Questionnaire Shape Concern subscale) and other manifestations of body image disturbance including body checking and body image quality of life. BodyWise appeared acceptable to participants, and was easy to deliver within the pragmatics of a busy eating disorder service. There is potential for its wider dissemination as a precursor to more active body image interventions. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association. PMID:25382845

Mountford, Victoria A; Brown, Amy; Bamford, Bryony; Saeidi, Saeideh; Morgan, John F; Lacey, Hubert

2014-11-01

164

New Imaging Strategies Using a Motion-Resistant Liver Sequence in Uncooperative Patients  

PubMed Central

MR imaging has unique benefits for evaluating the liver because of its high-resolution capability and ability to permit detailed assessment of anatomic lesions. In uncooperative patients, motion artifacts can impair the image quality and lead to the loss of diagnostic information. In this setting, the recent advances in motion-resistant liver MR techniques, including faster imaging protocols (e.g., dual-echo magnetization-prepared rapid-acquisition gradient echo (MP-RAGE), view-sharing technique), the data under-sampling (e.g., gradient recalled echo (GRE) with controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA), single-shot echo-train spin-echo (SS-ETSE)), and motion-artifact minimization method (e.g., radial GRE with/without k-space-weighted image contrast (KWIC)), can provide consistent, artifact-free images with adequate image quality and can lead to promising diagnostic performance. Understanding of the different motion-resistant options allows radiologists to adopt the most appropriate technique for their clinical practice and thereby significantly improve patient care. PMID:25243115

Kim, Bong Soo; Lee, Kyung Ryeol; Goh, Myeng Ju

2014-01-01

165

Longitudinal changes in patients with traumatic brain injury assessed with diffusion tensor and volumetric imaging  

PubMed Central

Traumatic brain injury (TBI) is associated with brain volume loss, but there is little information on the regional gray matter (GM) and white matter (WM) changes that contribute to overall loss. Since axonal injury is a common occurrence in TBI, imaging methods that are sensitive to WM damage such as diffusion-tensor imaging (DTI) may be useful for characterizing microstructural brain injury contributing to regional WM loss in TBI. High-resolution T1-weighted imaging and DTI were used to evaluate regional changes in TBI patients compared to matched controls. Patients received neuropsychological testing and were imaged approximately 2 months and 12.7 months post injury. Paradoxically, neuropsychological function improved from Visit 1 to Visit 2, while voxel-based analyses of fractional anisotropy (FA), and mean diffusivity (MD) from the DTI images, and voxel-based analyses of the GM and WM probability maps from the T1-weighted images, mainly revealed significantly greater deleterious GM and WM change over time in patients compared to controls. Cross-sectional comparisons of the DTI measures indicated that patients have decreased FA and increased MD compared to controls over large regions of the brain. TBI affected virtually all of the major fiber bundles in the brain including the corpus callosum, cingulum, the superior and inferior longitudinal fascicules, the uncinate fasciculus, and brain stem fiber tracts. The results indicate that both GM and WM degeneration are significant contributors to brain volume loss in the months following brain injury, and also suggest that DTI measures may be more useful than high-resolution anatomical images in assessment of group differences. PMID:18556217

Bendlin, Barbara; Ries, Michele L.; Lazar, Mariana; Alexander, Andrew L.; Dempsey, Robert J.; Rowley, Howard A.; Sherman, Jack E.; Johnson, Sterling C.

2008-01-01

166

Imaging strategies for detection of urgent conditions in patients with acute abdominal pain: diagnostic accuracy study  

PubMed Central

Objective To identify an optimal imaging strategy for the accurate detection of urgent conditions in patients with acute abdominal pain. Design Fully paired multicentre diagnostic accuracy study with prospective data collection. Setting Emergency departments of two university hospitals and four large teaching hospitals in the Netherlands. Participants 1021 patients with non-traumatic abdominal pain of >2 hours’ and <5 days’ duration. Exclusion criteria were discharge from the emergency department with no imaging considered warranted by the treating physician, pregnancy, and haemorrhagic shock. Intervention All patients had plain radiographs (upright chest and supine abdominal), ultrasonography, and computed tomography (CT) after clinical and laboratory examination. A panel of experienced physicians assigned a final diagnosis after six months and classified the condition as urgent or non-urgent. Main outcome measures Sensitivity and specificity for urgent conditions, percentage of missed cases and false positives, and exposure to radiation for single imaging strategies, conditional imaging strategies (CT after initial ultrasonography), and strategies driven by body mass index and age or by location of pain. Results 661 (65%) patients had a final diagnosis classified as urgent. The initial clinical diagnosis resulted in many false positive urgent diagnoses, which were significantly reduced after ultrasonography or CT. CT detected more urgent diagnoses than did ultrasonography: sensitivity was 89% (95% confidence interval 87% to 92%) for CT and 70% (67% to 74%) for ultrasonography (P<0.001). A conditional strategy with CT only after negative or inconclusive ultrasonography yielded the highest sensitivity, missing only 6% of urgent cases. With this strategy, only 49% (46% to 52%) of patients would have CT. Alternative strategies guided by body mass index, age, or location of the pain would all result in a loss of sensitivity. Conclusion Although CT is the most sensitive imaging investigation for detecting urgent conditions in patients with abdominal pain, using ultrasonography first and CT only in those with negative or inconclusive ultrasonography results in the best sensitivity and lowers exposure to radiation. PMID:19561056

2009-01-01

167

Circulating CD56(dim) natural killer cells and CD56(+) T cells that produce interferon-? or interleukin-10 are expanded in asymptomatic, E antigen-negative patients with persistent hepatitis B virus infection.  

PubMed

Infection with hepatitis B virus (HBV) can result in spontaneous resolution or chronic infection, which can remain asymptomatic or can progress to cirrhosis and/or hepatocellular carcinoma. The host immune response is thought to be a major determinant of the outcome of HBV infection and virus-specific cytotoxic T lymphocytes (CTL) can mediate immunity against the virus and cause liver pathology. Antigen-nonspecific innate lymphocytes may also contribute to HBV infection and liver disease, therefore, we examined the frequencies, phenotypes, cytolytic activities and cytokine profiles of circulating natural killer (NK) cells, CD1d-restricted invariant natural killer T (iNKT) cells and CD56(+) T cells in 102 asymptomatic HBV-infected patients and compared them with those in 66 uninfected control subjects. NK cells expressing low levels of CD56 (CD56(dim) ) and CD56(+) T cells were significantly expanded in the circulation of HBV-infected patients compared with control subjects. CD1d expression and iNKT cell frequencies were similar in both groups. Despite these expansions, we did not detect augmented natural or cytokine-induced cytotoxicity in the HBV-infected subjects. All lymphocyte populations studied produced interferon-? (IFN-?) significantly more frequently when taken from HBV-infected patients compared with when taken from healthy controls. Additionally, NK cells from the patients more frequently produced interleukin-10. As our HBV-infected cohort consisted of asymptomatic patients with low viral loads, we propose that CD56(dim) NK cells and CD56(+) T cells control HBV infection by noncytolytic mechanisms. PMID:25186004

Conroy, M J; Mac Nicholas, R; Grealy, R; Taylor, M; Otegbayo, J A; O'Dea, S; Mulcahy, F; Ryan, T; Norris, S; Doherty, D G

2015-03-01

168

[Usefulness of magnetic resonance imaging for managing patients with prosthetic carbon valve in the mitral position].  

PubMed

The safety, findings and clinical usefulness of magnetic resonance (MR) imaging were assessed in patients with a prosthetic carbon valve in the mitral position. In vitro deflection, heating and image distortion due to the magnetic field of a 1.5 tesla MR machine were examined in three carbon valves (CarboMedics, St. Jude Medical and Björk-Shiley valves). In vivo MR imaging of the left ventricular horizontal long-axis, vertical long-axis and short-axis views was performed by electrocardiographically synchronized spin echo and field (gradient) echo techniques in eight patients with prosthetic mitral carbon valves, consisting of six CarboMedics valves, one St. Jude Medical valve and one Björk-Shiley valve. No deflection and significant heating was seen in all three valves in vitro. Although little image distortion was shown in the CarboMedics and St. Jude Medical valves, a small distortion toward the frequency encoded direction was seen in the Björk-Shiley valve but caused no difficulty in assessing the surrounding images. Four of the eight patients had normal sinus rhythm and the other four had atrial fibrillation. The prosthetic valves were depicted as signal voids in the images taken by both spin echo and field echo techniques in vivo. Clear structural information with little image distortion of the adjacent tissues of the prosthetic valves were obtained in all patients, although the image of the Björk-Shiley valve which contained stainless steel in the frame had a slightly stronger distortion than those of the CarboMedics and St. Jude Medical valves which contained titanium. The stainless wire suture material used to close the sternal incision was depicted as a signal void, and the areas of the signal loss were larger in the images taken by the field echo technique than those by the spin echo technique. The images taken by the spin echo technique in patients with atrial fibrillation had reduced quality due to the irregularity of repetition time. Cine MR imaging by the field echo technique showed physiological mitral regurgitant jets as signal loss within the flowing blood, which appeared as high signal intensity, bidirectionally in the bileaflet mechanical valve and unidirectionally in the monoleaflet mechanical valve. An abnormal cavity was seen behind the basal left ventricular myocardium in one patient with a CarboMedics valve. The wall of the abnormal cavity was disrupted abruptly and the rest of the wall consisted of pericardium and adjacent tissue in the image taken by the spin echo technique. The image taken by the field echo technique showed an abnormal jet flow from the basal part of the left ventricular cavity into the abnormal cavity, which was compatible with left ventricular pseudoaneurysm. Two-dimensional echocardiography and Doppler color flow mapping disclosed the abnormal cavity and the abnormal flow inside, but failed to show the connection between the left ventricle and the cavity due to reverberation of the ultrasound signal by the prosthetic valve. These findings suggest that MR imaging is a safe and promising method to assess the complications and valvular function in patients with a prosthetic carbon valve in the mitral position. PMID:9395956

Koito, H; Imai, Y; Suzuki, J; Ohkubo, N; Nakamura, C; Takahashi, H; Iwasaka, T; Inada, M

1997-11-01

169

Shaped, lead-loaded acrylic filters for patient exposure reduction and image-quality improvement  

SciTech Connect

Shaped filters that are constructed of lead-loaded acrylic material for use in patient radiography are discussed. Use of the filters will result in improved overall image quality with significant exposure reduction to the patient (approximately a 2X reduction in breast exposure and a 3X reduction in thyroid gland exposure). Detailed drawings of the shaped filters for scoliosis radiography, cervical spine radiography, and for long film changers in special procedures are provided. The use of the scoliosis filters is detailed and includes phantom and patient radiographs and dose reduction information.

Gray, J.E.; Stears, J.G.; Frank, E.D.

1983-03-01

170

A Patient-Specific Segmentation Framework for Longitudinal MR Images of Traumatic Brain Injury  

E-print Network

A Patient-Specific Segmentation Framework for Longitudinal MR Images of Traumatic Brain Injury Bo of California, Los Angeles, California. ABSTRACT Traumatic brain injury (TBI) is a major cause of death, Longitudinal analysis 1. INTRODUCTION Traumatic brain injury (TBI) occurs when an external force traumatically

Utah, University of

171

Imaging of patients with severe emphysema considered for lung volume reduction surgery  

Microsoft Academic Search

Lung volume reduction surgery has recently been reintroduced as a palliative treatment for patients with severe emphysema. Selection criteria vary between centres and imaging is exten- sively used, but the exact role of individual techniques in the selection process is still emerging. In the UK, pulmonary emphysema and chronic bronchitis are the commonest causes of respiratory morbidity in adults characterized

J R CLEVERLEY; D M HANSELL

172

Radiation dose to patients and image quality evaluation from coronary 256-slice computed tomographic angiography  

Microsoft Academic Search

The aim of this study is to assess radiation dose and the corresponding image quality from suggested CT protocols which depends on different mean heart rate and high heart rate variability by using 256-slice CT. Fifty consecutive patients referred for a cardiac CT examination were included in this study. All coronary computed tomographic angiography (CCTA) examinations were performed on a

Liang-Kuang Chen; Tung-Hsin Wu; Ching-Ching Yang; Chia-Jung Tsai; Jason J. S. Lee

2010-01-01

173

Comparison of setup error using different reference images: a phantom and lung cancer patients study  

SciTech Connect

The purpose of this study was to compare setup errors obtained with kilovoltage cone-beam computed tomography (CBCT) and 2 different kinds of reference images, free-breathing 3D localization CT images (FB-CT) and the average images of 4-D localization CT images (AVG-CT) for phantom and lung cancer patients. This study also explored the correlation between the difference of translational setup errors and the gross tumor volume (GTV) motion. A respiratory phantom and 14 patients were enrolled in this study. For phantom and each patient, 3D helical CT and 4D CT images were acquired, and AVG-CT images were generated from the 4D CT. The setup errors were determined based on the image registration between the CBCT and the 2 different reference images, respectively. The data for both translational and rotational setup errors were analyzed and compared. The GTV centroid movement as well as its correlation with the translational setup error differences was also evaluated. In the phantom study, the AVG-CT method was more accurate than the FB-CT method. For patients, the translational setup errors based on FB-CT were significantly larger than those from AVG-CT in the left-right (LR), superior-inferior (SI), and anterior-posterior (AP) directions (p < 0.05). Translational setup errors differed by >1 mm in 32.6% and >2 mm in 12.9% of CBCT scans. The rotational setup errors from FB-CT were significantly different from those from AVG-CT in the LR and AP directions (p < 0.05). The correlation coefficient of the translational setup error differences and the GTV centroid movement in the LR, SI, and AP directions was 0.515 (p = 0.060), 0.902 (p < 0.001), and 0.510 (p = 0.062), respectively. For lung cancer patients, respiration may affect the on-line target position location. AVG-CT provides different reference information than FB-CT. The difference in SI direction caused by the 2 methods increases with the GTV movement. Therefore, AVG-CT should be the prefered choice of reference images.

Jiang Bo [Department of Radiation Oncology, Cancer Institute (Hospital), Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing (China); Dai Jianrong, E-mail: jiangbo122@126.com [Department of Radiation Oncology, Cancer Institute (Hospital), Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing (China); Zhang Ye; Zhang Ke; Men Kuo; Zhou Zongmei; Liang Jun; Wang Lvhua [Department of Radiation Oncology, Cancer Institute (Hospital), Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing (China)

2012-04-01

174

Chagasic granulomatous encephalitis in immunosuppressed patients. Computed tomography and magnetic resonance imaging findings.  

PubMed

American trypanosomiasis (Chagas' disease), a zoonosis caused by Trypanosoma cruzi with a high incidence in Latin America, may induce an uncommon form of localized encephalitis termed "chagoma", found in few immunocompromised patients. The computed tomography (CT) and magnetic resonance imaging (MRI) findings of brain chagoma are reported for 3 males (ages 32, 32 and 9 yr), the first 2 infected with human immunodeficiency virus (HIV) and the third with acute lymphoblastic leukemia. Diagnosis was confirmed by biopsy. CT disclosed a single, supratentorial, nodular-shaped lesion that substantially enhanced with contrast material, localized in parietal or frontal lobes. T1-weighted MRI showed hypointense lesions that enhanced with gadolinium-diethylenetriaminepentaacetic acid, corresponding to extensive hyperintense areas on T2-weighted images, producing mass effect. The imaging pattern of brain chagoma presented here is similar to that of cerebral toxoplasmosis and should be considered in the differential diagnosis of an intracerebral mass lesion in immunocompromised patients. PMID:8634494

Di Lorenzo, G A; Pagano, M A; Taratuto, A L; Garau, M L; Meli, F J; Pomsztein, M D

1996-04-01

175

Malignant lymphoma of the breast in a male patient: ultrasound imaging features.  

PubMed

Non-Hodgkin lymphoma (NHL) of the breast is a rare disease. Herein, we report a rare case of secondary involvement of the breast by NHL in a male patient and the ultrasound imaging findings. A 70-year-old man noticed an induration of the subareolar region of the right breast. He had been diagnosed as having mantle cell lymphoma 5 years before and treated with several series of chemoradiotherapy. On supine examination, palpation revealed bilateral breast enlargement, but detection of a lump was difficult. Ultrasonography showed a hypoechoic non-mass image-forming lesion in the subareolar region of the right breast. The final pathological diagnosis was recurrence of mantle cell lymphoma in the right breast. The diagnosis of malignant lymphoma of the breast by imaging modalities is difficult because there are no specific features. Breast lymphoma should be included with gynecomastia and breast cancer in the differential diagnosis of male patients with breast enlargement. PMID:22396322

Ikeda, Tatsuhiko; Bando, Hiroko; Iguchi, Akiko; Tanaka, Yuko; Tohno, Eriko; Hara, Hisato

2015-03-01

176

Brain Magnetic Resonance Imaging Findings in Young Patients with Hepatosplenic Schistosomiasis Mansoni without Overt Symptoms  

PubMed Central

The purpose of this study was to describe the brain magnetic resonance imaging (MRI) findings in young patients with hepatosplenic schistosomiasis mansoni without overt neurologic manifestations. This study included 34 young persons (age range = 9–25 years) with hepatosplenic schistosomiasis mansoni who had been previously treated. Patients were scanned on a 1.5-T system that included multiplanar pre-contrast and post-contrast sequences, and reports were completed by two radiologists after a consensus review. Twenty (58.8%) patients had MRI signal changes that were believed to be related to schistosomiasis mansoni. Twelve of the 20 patients had small focal hyperintensities on T2WI in the cerebral white matter, and eight patients had symmetric hyperintense basal ganglia on T1WI. There was a high frequency of brain MRI signal abnormalities in this series. Although not specific, these findings may be related to schistosomiasis. PMID:22665605

Manzella, Adonis; Borba-Filho, Paulo; Brandt, Carlos T.; Oliveira, Keyla

2012-01-01

177

Potential Applications of Imaging and Image-Guided Radiotherapy for Brain Metastases and Glioblastoma to Improve Patient Quality of Life  

PubMed Central

Treatment of glioblastoma multiforme (GBM) and brain metastasis remains a challenge because of the poor survival and the potential for brain damage following radiation. Despite concurrent chemotherapy and radiation dose escalation, local recurrence remains the predominant pattern of failure in GBM most likely secondary to repopulation of cancer stem cells. Even though radiotherapy is highly effective for local control of radio-resistant tumors such as melanoma and renal cell cancer, systemic disease progression is the cause of death in most patients with brain metastasis. Preservation of quality of life (QOL) of cancer survivors is the main issue for patients with brain metastasis. Image-guided radiotherapy (IGRT) by virtue of precise radiation dose delivery may reduce treatment time of patients with GBM without excessive toxicity and potentially improve neurocognitive function with preservation of local control in patients with brain metastasis. Future prospective trials for primary brain tumors or brain metastasis should include IGRT to assess its efficacy to improve patient QOL. PMID:24312897

Nguyen, Nam P.; Nguyen, Mai L.; Vock, Jacqueline; Lemanski, Claire; Kerr, Christine; Vinh-Hung, Vincent; Chi, Alexander; Khan, Rihan; Woods, William; Altdorfer, Gabor; D’Andrea, Mark; Karlsson, Ulf; Hamilton, Russ; Ampil, Fred

2013-01-01

178

Will imaging assist in the selection of patients with heart failure for an ICD?  

PubMed

Sudden cardiac death remains the leading cause of death in the U.S. A left ventricular ejection fraction (LVEF)<30% to 35% identifies a population of patients at increased risk for sudden cardiac death. Once identified, an implantable cardioverter-defibrillator (ICD) is effective in reducing the occurrence of sudden cardiac death. Yet in a substantial proportion of patients who receive an ICD based on reduced LVEF, the device never delivers therapy. Furthermore, the majority of patients who die suddenly do not qualify for ICD placement under current LVEF-based criteria in the guidelines. This review considers the potential role of cardiac imaging in improving the selection of patients most likely to benefit from an ICD. The presence of myocardial scar and/or unrevascularized myocardial ischemia provides an important substrate for the occurrence of potentially fatal ventricular arrhythmias. The presence of clinical heart failure further increases the risk of ventricular arrhythmia. The sympathetic nervous system provides an important trigger for major arrhythmic events, both through global overactivity and through regional heterogeneity of sympathetic activity. A mismatch of myocardial perfusion and innervation may pose a particularly great risk. Imaging modalities provide unique opportunities to investigate the anatomic and pathophysiologic substrates, as well as the triggering effects of cardiac sympathetic innervation. Combining imaging and electrophysiologic modalities offers promise for improved accuracy in future selection of patients with heart failure for ICD placement. PMID:20129539

Gerson, Myron C; Abdallah, Mouhamad; Muth, James N; Costea, Alexandru I

2010-01-01

179

Grazing incidence beam expander  

SciTech Connect

A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.

1985-01-01

180

The Expanding Universe  

NSDL National Science Digital Library

This lesson plan is part of the Center for Educational Resources (CERES), a series of web-based astronomy lessons created by a team of master teachers, university faculty, and NASA researchers. In this lesson, students gain a deeper understanding of cosmology by gathering evidence for the Big Bang theory. They explore the Hubble Law and create a model of the expanding universe. This lesson contains expected outcomes for students, materials, background information, follow-up questions, and assessment procedures.

George Tuthill

181

Diffusion kurtosis imaging discriminates patients with white matter lesions from healthy subjects.  

PubMed

This work illustrates that DKI reveals white matter lesions and also discriminates healthy subjects from patients with white matter lesions. To show this capability, we have investigated DKI images of a healthy subject and a patient with white matter lesions. The analysis was performed both between and within subjects. Regions of Interest (ROIs) for lesion and normal white matter in the patient images are selected manually (for within subject study) and also the corresponding ROIs in the healthy subject are defined (for between subject study). The results of comparing the estimated values for apparent diffusion and kurtosis parameters show that both D(app) and K(app) can distinguish normal and abnormal tissues. K(app) (D(app)) of the normal regions is greater (lower) than that of the abnormal regions. Another investigation over all voxels in the brain shows an important feature of kurtosis in determining white matter lesions. PMID:22254922

Iraji, Armin; Davoodi-Bojd, Esmaeil; Soltanian-Zadeh, Hamid; Hossein-Zadeh, Gholam-Ali; Jiang, Quan

2011-01-01

182

To see or not to see: a qualitative interview study of patients’ views on their own diagnostic images  

PubMed Central

Objectives To ascertain what meaning individuals attach to perceiving images of their own interior body and how the images and their meanings affect the clinical consultation. Design Face-to-face semistructured interviews. Participants 25 adult patients in southern England who, within the preceding 12?months, had been referred for diagnostic imaging. Setting Community. Results For patients, being shown their own X-rays, MRIs or CT images creates a variety of effects: (1) a sense of better understanding of the diagnosis; (2) validation of their sensory and emotional response to the illness or injury and (3) an alteration to the tenor and nature of the clinical encounter between patient and physician. In addition to meanings attached to these images, patients also impute meaning to the physician's decision not to share an image with them. The desire to see their image was greater in those patients with a skeletal injury; patients are less keen on viewing abdominal or other soft tissue images. Conclusions Viewing images of one's interior, invisible body is powerful and resonant in a number of ways. The experience of not seeing, whether through the patient's or the physician's choice, is also fraught with meaning. PMID:25082418

Carlin, Leslie E; Smith, Helen E; Henwood, Flis

2014-01-01

183

Transient MR Signal Changes in Patients with Generalized Tonicoclonic Seizure or Status Epilepticus: Periictal Diffusion-weighted Imaging  

Microsoft Academic Search

BACKGROUND AND PURPOSE:Our purpose was to investigate transient MR signal chang- es on periictal MR images of patients with generalized tonicoclonic seizure or status epilepticus and to evaluate the clinical significance of these findings for differential diagnosis and under- standing of the pathophysiology of seizure-induced brain changes. METHODS: Eight patients with MR images that were obtained within 3 days after

Jeong-Ah Kim; Jin Il Chung; Pyeong Ho Yoon; Dong Ik Kim; Tae-Sub Chung; Eun-Ju Kim; Eun-Kee Jeong

184

Implementing novel imaging methods for improved diagnosis of disorder of consciousness patients.  

PubMed

The clinical evaluation of consciousness in disorder of consciousness (DOC) patients based on their exhibited behavior is difficult and remains erroneous in many cases. Recent studies demonstrated different levels of stimulus processing as well as evidence of some level of awareness in sub-groups of these patients. The aim of the current study was to examine the plausibility and challenges of implementing a clinical service for evaluation of consciousness level in DOC patients. Eleven Patients (ages 11-67) diagnosed as being in vegetative or minimal conscious states were included. Functional MRI evaluations included auditory, language, voice familiarity, imagery, and visual tests. In 9 patients auditory-related activation was found, however only in 5 of the subjects was differential activation found for language. Six patients exhibited differential response to their own name. In three patients a response to visual stimuli was identified. In one patient the auditory and linguistic systems were clearly activated in a hierarchical pattern, and moreover willful modulation of brain activity was identified in the imagery test. We discuss the importance of using a wide battery of tests, the difference between our clinical cohort and previous publications, as well as the challenges of clinically implementing this method. Translating novel imaging methods into the clinical evaluation of DOC patients is essential for better diagnosis and may encourage treatment development. PMID:24007872

Bick, Atira S; Leker, Ronen R; Ben-Hur, Tamir; Levin, Netta

2013-11-15

185

Image cytometric DNA analysis of mucosal biopsies in patients with primary achalasia  

PubMed Central

AIM: To determine DNA aneuploidy in mucosal biopsies of achalasia patients for subsequent rapid diagnosis. METHODS: Biopsies from the middle third of the esophagus were obtained in 15 patients with achalasia. Immunohistochemical staining was carried out with monoclonal antibodies MIB-1 for Ki67 and PAb 1801 for p53, in addition to the conventional histologic examination for dysplasia. Nuclei of fresh biopsy material were enzymatically and mechanically isolated, and the DNA content was determined with image cytometry after Feulgen staining. DNA grading of malignancy was assessed according to Boecking to determine the variability of DNA values noted around the normal diploid peak. Further indices measured included the aneuploid rate, and the 5c-, 7c- and 9c-exceeding rate. RESULTS: The histological examination did not demonstrate dysplasia; while MIB-1 (basal) showed a positive reaction in 8/15 achalasia specimens, p53 was negative in all specimens. Image cytometric DNA analysis detected aneuploidy in 4/15 (26.7%) specimens. Samples from 15 patients with squamous cell carcinoma as well as specimens obtained exclusively 2 cm proximal to the tumor served as reference tests. All carcinomas (15/15) as well as 9 of the peritumoral samples (9/15) were aneuploid. The comparison of biopsies from achalasia patients with peritumoral and carcinoma specimens revealed statistically significant differences regarding the aneuploid rate (diploid: P < 0.0001; tetraploid: P = 0.001), grading of malignancy according to Boecking (P < 0.0001) and the 5c- (P < 0.0001), 7c- (P < 0.0001), and 9c- (P = 0.0001) exceeding rate with progredient DNA alterations in the respective order. CONCLUSION: The finding that DNA aneuploidy was identified by image cytometry in esophageal specimens of patients with achalasia, which may be due to specific chromosomal alterations presenting as precancerous lesions in 27% of patients, leads us to conclude that image cytometry represents a valuable screening tool. PMID:16718781

Gockel, I; Kämmerer, P; Brieger, J; Heinrich, UR; Mann, WJ; Bittinger, F; Eckardt, VF; Junginger, T

2006-01-01

186

Indium-111 chloride imaging in patients with suspected abscesses: concise communication  

SciTech Connect

Two hundred and fifty-eight patients with clinically suspected inflammatory processes were studied. Seventy-two images were categorized as true positive; 211 as true negative. There were nine false-positive studies, four of which were due to activity in beds of excised organs. There were six false-negative studies, four of which were due to walled-off abscesses found either at surgery or biopsy. The sensitivity was 92%, the specificity 95%, and the accuracy 94%. This study shows that indium-111 chloride imaging provides a reliable way to locate inflammatory processes and overcomes the disadvantages of other imaging agents, for example gastrointestinal activity or the demonstration of healing surgical wounds with gallium-67, and the false-positive images due to cystic fibrosis and other respiratory diseases, or accessory spleens as seen with In-111-labeled white cells.

Sayle, B.A.; Balachandran, S.; Rogers, C.A.

1983-12-01

187

Population of 100 realistic, patient-based computerized breast phantoms for multi-modality imaging research  

NASA Astrophysics Data System (ADS)

Breast imaging is an important area of research with many new techniques being investigated to further reduce the morbidity and mortality of breast cancer through early detection. Computerized phantoms can provide an essential tool to quantitatively compare new imaging systems and techniques. Current phantoms, however, lack sufficient realism in depicting the complex 3D anatomy of the breast. In this work, we created one-hundred realistic and detailed 3D computational breast phantoms based on high-resolution CT datasets from normal patients. We also developed a finiteelement application to simulate different compression states of the breast, making the phantoms applicable to multimodality imaging research. The breast phantoms and tools developed in this work were packaged into user-friendly software applications to distribute for breast imaging research.

Segars, W. Paul; Veress, Alexander I.; Wells, Jered R.; Sturgeon, Gregory M.; Kiarashi, Nooshin; Lo, Joseph Y.; Samei, Ehsan; Dobbins, James T.

2014-03-01

188

Body image disturbance in patients with borderline personality disorder: impact of eating disorders and perceived childhood sexual abuse.  

PubMed

Body image disturbances occur in women with borderline personality disorder (BPD). Systematic research on these characteristics in well-defined BPD groups is lacking. It is unknown, if the disturbances are related to eating disorders and childhood sexual abuse (CSA), which frequently co-occur in patients with BPD. In the present study, cognitive-affective and behavioral components of body image for 89 female patients with BPD (49 with lifetime eating disorders) and 41 healthy participants were assessed via Body Image Avoidance Questionnaire (BIAQ) and Multidimensional Body-Self Relations Questionnaire (MBSRQ). Within the BPD group, 43 patients reported a history of CSA. Compared to healthy controls, BPD patients reported significantly more negative scores in the BIAQ and the MBSRQ. Both a history of CSA and a comorbid eating disorder were independently associated with an even more negative body image. Results suggest a disturbance of cognitive-affective and behavioral components of body image in female BPD patients. PMID:23375838

Dyer, Anne; Borgmann, Elisabeth; Feldmann, Robert E; Kleindienst, Nikolaus; Priebe, Kathlen; Bohus, Martin; Vocks, Silja

2013-03-01

189

Quantitative thallium-201 myocardial imaging in assessing right ventricular pressure in patients with congenital heart defects.  

PubMed Central

Thallium-201 myocardial scintigraphy was performed in patients with congenital heart defects to determine whether, by quantification of right ventricular isotope uptake, one could assess the degree of right ventricular hypertrophy and so predict the level of right ventricular pressure. A total of 24 patients ranging in age from 7 months to 30 years was studied; 18 were studied before corrective surgery and six after operation. All but three had congenital heart defects which had resulted in pressure and/or volume-overload of the right ventricle. At routine cardiac catheterisation, 20 microCi/kg thallium-201 as thallous chloride was injected through the venous catheter and myocardial images were recorded in anterior and left anterior oblique projections; these were subsequently analysed quantitatively and qualitatively. Insignificant right ventricular thallium-201 counts judged as being less than 1 per cent of the injected dose or less than 0.3 of the left ventricular counts were present in six patients all with right ventricular peak systolic pressure less than 30 mmHg. In the remaining 18 patients there was a good correlation between the right ventricular/left ventricular peak systolic pressure ratio and the right ventricular/left ventricular thallium-201 counts ratio. All patients with right ventricular/left ventricular peak systolic pressure less than 0.5 had right ventricular/left ventricular thallium-201 counts less than 0.4. Qualitative evaluation of right ventricular isotope intensity proved helpful mainly in distinguishing the patients with right ventricular pressures at or above systemic levels. Thus quantitative analysis of myocardial imaging with thallium-201 is of use clinically in patients with congenital heart defects, in assessing the severity of pulmonary stenosis or the presence of pulmonary artery hypertension. Images PMID:7459178

Rabinovitch, M; Fischer, K C; Treves, S

1981-01-01

190

Myeloid differentiation and maturation of SCF+IL-3+IL-11 expanded AC133+/CD34+ cells selected from high-risk breast cancer patients.  

PubMed

The AC133 antigen is selectively expressed on subset of CD 34+ cells isolated from leukapheresis products from high risk breast cancer patients receiving chemotherapy plus G-CSF. MiniMACS AC133+ isolated cells contained a mean of 85% (80-90) AC133+ cells. Enriched AC133+ cells coexpressed 80% CD34+, 6.6% CD33+ and 2% CD15+. Separated AC133+ cells contained 600 GFU-GM/10(4) cells and 70 BFU-E/10(4) cells. Flow-cytometric analysis indicated that AC133+ cells were isolated from cells population with low granularity (SS), while CD33+ a CD15+ cells had a high granularity. After a seven-day ex vivo expansion in the presence of SCF + IL-3 + IL11, the expansion of cells increased 19.4 times. The mean percentage of blasts decreased from 100% at the start of culture to 81% on day 3 and 30% on day 7. Promyelocytes were slow to appear with 10% present on day 3, but thereafter increased to 33% on day 7. The appearance of myelocytes and metamyelocytes lagged 3 days behind promyelocytes and continued to increase during culture to become the predominant (30%) cell type on day 7. Very few neutrophils (2%) were observed in any of the cultures on day 7. Monocytes or macrophages were not detected on day 7. By day 7 megakaryocytes were present at low levels (10%). The mean value of CFU-GM in the culture after day 7 of ex vivo expansion in the presence of SCF+IL-3+IL-11 had increased 45-fold, BFU-E 5-fold. After 7 days of expansion with IL-3+SCF+IL-11 cells expressed a mean of 12% CD34+, 8% AC133+, 59% CD33+ and 30% CD15+. The aim of this experiment was to determine whether ex vivo culture of peripheral blood AC133+ cells could generate sufficient numbers of progenitors to potentially abrogate cytopenia after transplantation and passive purging of tumor cells. PMID:10985471

Filip, S; Vávrová, J; Vokurková, D; Bláha, M; Vanásek, J

2000-01-01

191

MR enterography imaging of Crohn’s disease in pediatric patients  

PubMed Central

Summary Background Crohn disease (CD) is a chronic inflammatory process of gastrointestinal tract, which frequently affects children. Recent advances in Magnetic Resonance Imaging (MRI) technique have made small bowel imaging possible, what is extremely useful in pediatrics. The purpose of this article is to describe the characteristic MR enterography findings and to present the advantages of this modality in pediatric patients. Material/Methods A group of 40 patients referred from the Department of Pediatric Gastroenterology and Nutrition, Medical University of Warsaw was included in the analysis. The patients’ age ranged from 7 to 18 years (mean age 14 years). Among the study participants, 28 patients were diagnosed with CD, whereas 12 patients had a history of ulcerative colitis or were strongly suspected of CD based on clinical data. The examinations were performed on GE Signa HD 1,5 T system. Small bowel distention was achieved by oral administration of 600–1000 ml of hyperosmotic solution of polyetylenglycol (PEG). Prior to the examination, 20–40 mg of a spasmolytic drug, hioscine-N-butylobromide (Buscolysin®), was administrated to reduce peristaltic movements. Results The abnormal small bowel segments were found in 21 patients and the features of colonic disease were detected in 5 patients. In 2 patients the lesions involved both small and large bowel. In 16 subjects mural changes were not found. Among studied patients, following signs of small bowel inflammation were fund: bowel wall thickening (n=21), submucosal edema (n=8), segment wall hyperenhancement (n=18), deep ulceration (n=6), fistula (n=3), stenosis (n=7), mesenteric signs such as hyperemia (n=9), fibrofatty proliferation (n=8) and lymphadenopathy (n=28). Conclusions MR enterography is an excellent examination, which provides an accurate information about severity and activity of and complications related to CD. It is especially valuable in children, because of lack of the negative consequences of repeated exposure to ionizing radiation. PMID:24778747

Podgórska, Joanna; Pacho, Ryszard; Albrecht, Piotr

2014-01-01

192

Is preoperative high-resolution magnetic resonance imaging accurate in predicting neurovascular compression in patients with trigeminal neuralgia?  

Microsoft Academic Search

High-resolution magnetic resonance imaging (HR-MRI) using three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) and double-dose contrast-enhanced three-dimensional fast spoiled gradient echo (3D-FSPGR) sequences is considered to be a useful tool in detecting neurovascular compression in patients with trigeminal neuralgia. The purpose of this study was to analyze the accuracy and preoperative diagnostic value of these high-resolution imaging techniques in patients

Ludwig Benes; Kiyoshi Shiratori; Mariana Gurschi; Ulrich Sure; Wuttipong Tirakotai; Boris Krischek; Helmut Bertalanffy

2005-01-01

193

Expandable Metallic Stent Treatment for Malignant Colorectal Strictures  

SciTech Connect

Four patients were treated by placement of an expandable metallic stent (two Gianturco Z-stents, two Ultraflex stents) for malignant colorectal strictures. All four patients were able to defecate after stent placement. Stent migration was recognized in one patient. Two patients suffered from tenesmus after stent placement.

Mishima, Kazuya; Sawada, Satoshi; Tanigawa, Noboru; Okuda, Yoshikazu [Department of Radiology, University Hospital of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-01 (Japan); Kobayashi, Masami [Department of Radiology, Tottori University Hospital, 36-1 Nishimachi, Yonago 683 (Japan); Koyama, Tsukasa [Department of Radiology, Yohka Hospital, 1878-1 Yohka, Hyougo 667 (Japan)

1999-03-15

194

[Roentgen image presentation in the patient's room. Simple equipment for demonstration and storage of roentgen images].  

PubMed

Immediate presentation of the more significant X-ray pictures facilitates planning and supervision of therapy in trauma surgery and orthopedics. If a wire rope is stretched in front of the window X-ray pictures can be clipped onto it, which avoids time-consuming searches. Suspended filing boxes placed in each sickroom make appropriate storage of each patient's X-ray pictures possible. The expenditure for all this amounted to 100 DM for each two-bedded room. Wire ropes and boxes were technically easy to install with a minimum investment of time. The presentation of X-ray pictures considerably increased the patients' understanding of their illness. It was also very rare for X-ray pictures to get mixed up once this system had been instituted. PMID:9082570

Prokop, A; Rehm, K E; Sagebiel, A

1996-12-01

195

Integration of patient specific modeling and advanced image processing techniques for image-guided neurosurgery  

NASA Astrophysics Data System (ADS)

A major challenge in neurosurgery oncology is to achieve maximal tumor removal while avoiding postoperative neurological deficits. Therefore, estimation of the brain deformation during the image guided tumor resection process is necessary. While anatomic MRI is highly sensitive for intracranial pathology, its specificity is limited. Different pathologies may have a very similar appearance on anatomic MRI. Moreover, since fMRI and diffusion tensor imaging are not currently available during the surgery, non-rigid registration of preoperative MR with intra-operative MR is necessary. This article presents a translational research effort that aims to integrate a number of state-of-the-art technologies for MRI-guided neurosurgery at the Brigham and Women's Hospital (BWH). Our ultimate goal is to routinely provide the neurosurgeons with accurate information about brain deformation during the surgery. The current system is tested during the weekly neurosurgeries in the open magnet at the BWH. The preoperative data is processed, prior to the surgery, while both rigid and non-rigid registration algorithms are run in the vicinity of the operating room. The system is tested on 9 image datasets from 3 neurosurgery cases. A method based on edge detection is used to quantitatively validate the results. 95% Hausdorff distance between points of the edges is used to estimate the accuracy of the registration. Overall, the minimum error is 1.4 mm, the mean error 2.23 mm, and the maximum error 3.1 mm. The mean ratio between brain deformation estimation and rigid alignment is 2.07. It demonstrates that our results can be 2.07 times more precise then the current technology. The major contribution of the presented work is the rigid and non-rigid alignment of the pre-operative fMRI with intra-operative 0.5T MRI achieved during the neurosurgery.

Archip, Neculai; Fedorov, Andriy; Lloyd, Bryn; Chrisochoides, Nikos; Golby, Alexandra; Black, Peter M.; Warfield, Simon K.

2006-03-01

196

Leg Edema Quantification for Heart Failure Patients via 3D Imaging  

PubMed Central

Heart failure is a common cardiac disease in elderly patients. After discharge, approximately 50% of all patients are readmitted to a hospital within six months. Recent studies show that home monitoring of heart failure patients can reduce the number of readmissions. Still, a large number of false positive alarms as well as underdiagnoses in other cases require more accurate alarm generation algorithms. New low-cost sensors for leg edema detection could be the missing link to help home monitoring to its breakthrough. We evaluated a 3D camera-based measurement setup in order to geometrically detect and quantify leg edemas. 3D images of legs were taken and geometric parameters were extracted semi-automatically from the images. Intra-subject variability for five healthy subjects was evaluated. Thereafter, correlation of 3D parameters with body weight and leg circumference was assessed during a clinical study at the Medical University of Graz. Strong correlation was found in between both reference values and instep height, while correlation in between curvature of the lower leg and references was very low. We conclude that 3D imaging might be a useful and cost-effective extension of home monitoring for heart failure patients, though further (prospective) studies are needed. PMID:23948874

Hayn, Dieter; Fruhwald, Friedrich; Riedel, Arthur; Falgenhauer, Markus; Schreier, Günter

2013-01-01

197

Magnetic resonance imaging in the follow-up of patients after aortic root reconstruction.  

PubMed

Long-term survival after replacement of the aortic root with a composite graft is improving. Late deaths are in several cases due to complications related to the previous surgery or to pathologies of the remaining aorta. Regular follow-up of these patients is of paramount importance. The purpose of this study is to evaluate the reliability of magnetic resonance imaging (MRI) in such cases. Twenty-seven patients (9 dissections and 18 aneurysms) who had undergone replacement of the aortic root with a composite graft were studied 20 to 167 months after surgery using magnetic resonance imaging with a 1.5 Tesla magnet. The left-ventricular outflow tract, the mechanical valve function, the proximal part of the coronary arteries, the graft, and the remaining aorta could be examined. No aortic insufficiency, ectasy of the proximal part of the coronaries, or pseudoaneurysms were seen. A widening of the remaining ascending aorta was noted in 4 cases. A still open, dissected pipe was visualized in 7 patients. Our conclusions are that MRI provides excellent images of the thoracic and abdominal aorta following surgical repair. The examination is becoming cost-competitive. More import is its very low risk for the patient group considered here: since it is non-invasive and requires no contrast medium or X-ray exposure, examinations can be repeated as required. PMID:8896161

Lepore, V; Lamm, C; Bugge, M; Larsson, S

1996-08-01

198

Cardiovascular magnetic resonance imaging as applied to patients with pulmonary arterial hypertension.  

PubMed

Numerous imaging techniques are currently used to evaluate pulmonary arterial hypertension (PAH), including echocardiography, x-ray, electrocardiogram (ECG), computed tomography and magnetic resonance imaging (MRI). All such modalities have inherent advantages and disadvantages governed by physical principles that result in their clinical utility. In that PAH is a progressive disorder characterised by abnormally elevated blood pressure of the pulmonary circulation that leads to extensive vascular remodelling and increased pulmonary vascular resistance, a technique that can encapsulate those specific features that depict the multiple facets of this disease has obvious advantages. Recent advances in cardiovascular MRI (CMR) technology have led to the development of dedicated techniques for non-invasive assessment of cardiovascular structure and function, including haemodynamical parameters in the pulmonary circulation, which are superior in their identification of pulmonary arterial right ventricular morphological changes. These advantages make CMR a very attractive modality for diagnosing, following and providing prognoses for PAH patients. In this review, we highlight the developments in the use of CMR for the diagnosis, assessment and monitoring of patients with PAH. These remarkable improvements in image acquisition, physiological imaging and contrast techniques place CMR in a prime position for defining this disease. In the coming decade, it is anticipated that continued improvements in CMR image acquisition, spatial and temporal resolution and analytical techniques will result in improved understanding of PAH pathophysiology, diagnosis and prognostic variables, as well as the replacement of the most, if not all, invasive procedures currently applied routinely to the evaluation of PAH. PMID:19624797

Biederman, R W W

2009-09-01

199

Clinical Decision Making With Myocardial Perfusion Imaging in Patients With Known or Suspected Coronary Artery Disease  

PubMed Central

Myocardial perfusion imaging (MPI) to diagnose coronary artery disease (CAD) is best performed in patients with intermediate pretest likelihood of disease; unfortunately, pretest likelihood is often overestimated, resulting in the inappropriate use of perfusion imaging. A good functional capacity often predicts low risk, and MPI for diagnosing CAD should be reserved for individuals with poor exercise capacity, abnormal resting electrocardiography, or an intermediate or high probability of CAD. With respect to anatomy-based testing, coronary CT angiography has a good negative predictive value, but stenosis severity correlates poorly with ischemia. Therefore decision making with respect to revascularization may be limited when a purely noninvasive anatomical test is used. Regarding perfusion imaging, the diagnostic accuracies of SPECT, PET, and cardiac magnetic resonance are similar, though fewer studies are available with cardiac magnetic resonance. PET coronary flow reserve may offer a negative predictive value sufficiently high to exclude severe CAD such that patients with mild to moderate reversible perfusion defects can forego invasive angiography. In addition, combined anatomical and perfusion-based imaging may eventually offer a definitive evaluation for diagnosing CAD, even in higher risk patients. Any remarkable findings on single-photon emission computed tomography and PET MPI studies are valuable for prognostication. Furthermore, assessment of myocardial blood flow with PET is particularly powerful for prognostication as it reflects the end result of many processes that lead to atherosclerosis. Decision making with respect to revascularization is limited for cardiac MRI and PET MPI. In contrast, retrospective radionuclide studies have identified an ischemic threshold, but randomized trials are needed. In patients with at least moderately reduced left ventricular systolic function, viable myocardium as assessed by PET or MRI, appears to identify patients who benefit from revascularization, but well-executed randomized trials are lacking. PMID:24948154

Cremer, Paul; Hachamovitch, Rory; Tamarappoo, Balaji

2015-01-01

200

Expanding the Visibility of Women's Work: Policy Implications.  

ERIC Educational Resources Information Center

Social conceptualization and media images of women's work affect health and social policy formation. Nurses can expand the visibility of women's work and promote gender-sensitive policies within and outside the profession. (SK)

Messias, DeAnne K. Hilfinger; Regev, Hanna; Im, Eun-Ok; Spiers, Judith A.; Van, Paulina; Meleis, Afaf Ibrahim

1997-01-01

201

Expanding impulsive gravitational waves  

E-print Network

We explicitly demonstrate that the known solutions for expanding impulsive spherical gravitational waves that have been obtained by a "cut and paste" method may be considered to be impulsive limits of the Robinson-Trautman vacuum type N solutions. We extend these results to all the generically distinct subclasses of these solutions in Minkowski, de Sitter and anti-de Sitter backgrounds. For these we express the solutions in terms of a continuous metric. Finally, we also extend the class of spherical shock gravitational waves to include a non-zero cosmological constant.

J. Podolsky; J. B. Griffiths

1999-07-06

202

Is the Earth Expanding ?  

NASA Astrophysics Data System (ADS)

Whether the Earth is expanding or contracting is an interesting problem in geoscience. The information of the secular change of the Earth's gravity field supports the conclusion that the Earth is expanding at least in recent years. The gravitational potential could be expressed as a spherical harmonic series outside the Earth. In practical applications, it could be approximately realized by a truncated series, e.g., EGM96 (the Earth Gravity Model 96), EIGEN-GL04C, etc. The principal moments of inertia of the Earth are related to the second-order coeffients of the spherical harmonic series. Based on EGM96 as well as EIGEN-GL04C, the principal moments of inertia and especially their temporal variations are determined. All the three principal moments of inertia are gradually increasing at almost the same rate in recent 10 years, which might be due to the following three causes: 1) the rise of the sea level; 2) the increase of the total mass of the Earth; 3) the expansion of the Earth in the general sense. Calculations show that the rise of the sea level has too week influence on the variation of the principal moments of inertia comparing with the actual observations, and consequently the cause 1) could be given up. As to the increase of the total mass of the Earth, there does not exist any definite evidence, especially, it has not been found that the geocentric constant GM (where G and M are gravitational constant and the total mass of the Earth respectively) varies with time by various satellite approaches. Hence, it is reasonable to assume that the increase of the principal moments of inertia is caused by the expansion of the interior of the Earth or at least the whole mantle. This clearly demonstrates that the Earth is expanding at least in recent 10 years. Preliminary numerical calculations show that the Earth is expanding at the rate around 0.6 mm/yr at least in recent 10 years. Taking into account the Dirac's large number postulate, it could be concluded that the Earth expansion has and will have happened continuously in a long geological history.

Shen, W.; Chen, W.; Li, J.

2007-12-01

203

Feasibility of Image-Guided Radiotherapy for Elderly Patients with Locally Advanced Rectal Cancer  

PubMed Central

Purpose The study aims to assess the tolerance of elderly patients (70 years or older) with locally advanced rectal cancers to image-guided radiotherapy (IGRT). A retrospective review of 13 elderly patients with locally advanced rectal cancer who underwent preoperative chemoradiation using IGRT was performed. Grade 3–4 acute toxicities, survival, and long-term complications were compared to 17 younger patients (<70 years) with the same disease stage. Results Grade 3–4 hematologic toxicities occurred in 7.6% and 0% (p?=?0.4) and gastrointestinal toxicities, and, in 15.2% and 5% (p?=?0.5), of elderly and younger patients, respectively. Surgery was aborted in three patients, two in the elderly group and one in the younger group. One patient in the elderly group died after surgery from cardiac arrhythmia. After a median follow-up of 34 months, five patients had died, two in the elderly and three in the younger group. The 3-year survival was 90.9% and 87.5% (p?=?0.7) for the elderly and younger group respectively. Two patients in the younger group developed ischemic colitis and fecal incontinence. There was no statistically significant difference in acute and late toxicities as well as survival between the two groups. Conclusions and Clinical Relevance Elderly patients with locally advanced rectal cancers may tolerate preoperative chemoradiation with IGRT as well as younger patients. Further prospective studies should be performed to investigate the potential of IGRT for possible cure in elderly patients with locally advanced rectal cancer. PMID:23967173

Nguyen, Nam P.; Ceizyk, Misty; Vock, Jacqueline; Vos, Paul; Chi, Alexander; Vinh-Hung, Vincent; Pugh, Judy; Khan, Rihan; Truong, Christina; Albala, Gabby; Locke, Angela; Karlsson, Ulf; Gelumbauskas, Steve; Smith-Raymond, Lexie

2013-01-01

204

The Primary Patency and Fracture Rates of Self-Expandable Nitinol Stents Placed in the Popliteal Arteries, Especially in the P2 and P3 Segments, in Korean Patients  

PubMed Central

Objective We wanted to evaluate the status of self-expandable nitinol stents implanted in the P2 and P3 segments of the popliteal artery in Korean patients. Materials and Methods We retrospectively analyzed 189 consecutive patients who underwent endovascular treatment for stenoocclusive lesions in the femoropopliteal artery from July 2003 to March 2009, and 18 patients who underwent stent placement in popliteal arterial P2 and P3 segments were finally enrolled. Lesion patency was evaluated by ultrasound or CT angiography, and stent fracture was assessed by plain X-rays at 1, 3, 6 and 12 months and annually thereafter. Results At the 1-month follow-up, stent fracture (Type 2) was seen in one limb (up to P3, 1 of 18, 6%) and it was identified in seven limbs at the 3-month follow-up (Type 2, Type 3, Type 4) (n = 1: up to P2; n = 6: P3). At the 6-month follow-up, one more fracture (Type 1) (up to P3) was noted. At the 1-year follow-up, there were no additional stent fractures. Just four limbs (up to P2) at the 2-year follow-up did not have stent fracture. The primary patency was 94%, 61% and 44% at 1, 3 and 6 months, respectively, and the group with stent implantation up to P3 had a higher fracture rate than that of the group that underwent stenting up to P2 (p < 0.05). Conclusion We suggest that stent placement up to the popliteal arterial P3 segment and over P2 in an Asian population can worsen the stent patency owing to stent fracture. It may be necessary to develop a stent design and structure for the Asian population that can resist the bending force in the knee joint. PMID:21430937

Chang, Il Soo; Park, Sang Woo; Yun, Ik Jin; Hwang, Jae Joon; Lee, Song Am; Kim, Jun Seok; Chang, Seong-Hwan; Jung, Hong Geun

2011-01-01

205

Feasibility of monitoring patient motion with opposed stereo infrared cameras during supine medical imaging  

NASA Astrophysics Data System (ADS)

Patient motion during single photon emission computed tomographic (SPECT) acquisition causes inconsistent projection data and reconstruction artifacts which can significantly affect diagnostic accuracy. We have investigated use of the Polaris stereo infrared motion-tracking system to track 6-Degrees-of-Freedom (6-DOF) motion of spherical reflectors (markers) on stretchy bands about the patient's chest and abdomen during cardiac SPECT imaging. The marker position information, obtained by opposed stereo infrared-camera systems, requires processing to correctly record tracked markers, and map Polaris co-ordinate data into the SPECT co-ordinate system. One stereo camera views the markers from the patient's head direction, and the other from the patient's foot direction. The need for opposed cameras is to overcome anatomical and geometrical limitations which sometimes prevent all markers from being seen by a single stereo camera. Both sets of marker data are required to compute rotational and translational 6-DOF motion of the patient which ultimately will be used for SPECT patient-motion corrections. The processing utilizes an algorithm involving least-squares fitting, to each other, of two 3-D point sets using singular value decomposition (SVD) resulting in the rotation matrix and translation of the rigid body centroid. We have previously demonstrated the ability to monitor multiple markers for twelve patients viewing from the foot end, and employed a neural network to separate the periodic respiratory motion component of marker motion from aperiodic body motion. We plan to initiate routine 6-DOF tracking of patient motion during SPECT imaging in the future, and are herein evaluating the feasibility of employing opposed stereo cameras.

Beach, Richard D.; McNamara, Joseph E.; Terlecki, George; King, Michael A.

2006-10-01

206

Correlative Imaging in a Patient with Cystic Thymoma: CT, MR and PET/CT Comparison  

PubMed Central

Summary Background Cystic thymoma is a rare variant of thymic neoplasm characterized by almost complete cystic degeneration with mixed internal structure. We describe a case of a 60 year-old woman with a cystic thymoma studied with advanced tomographic imaging stydies. CT, MRI and PET/CT with 18F-FDG were performed; volumetric CT and MRI images provided better anatomic evaluation for pre-operative assessment, while PET/CT was helpful for lesion characterization based on 18F-FDG uptake. Although imaging studies are mandatory for pre-operative evaluation of cystic thymoma, final diagnosis still remains surgical. Case Report A 60-year-old woman with recent chest pain and no history of previous disease was admitted to our departement to investigate the result of a previous chest X-ray that showed bilateral mediastinal enlargement; for this purpose, enhanced chest CT scan was performed using a 64-rows scanner (Toshiba, Aquilion 64, Japan) before and after intravenous bolus administration of iodinated non ionic contrast agent; CT images demonstrated the presence of a large mediastinal mass (11×8 cm) located in the anterior mediastinum who extended from the anonymous vein to the cardio-phrenic space, compressing the left atrium and causing medium lobe atelectasis; bilateral pleural effusion was also present. Conclusions In conclusion, correlative imaging plays a foundamental role for the diagnostic evaluation of patient with cystic thymoma. In particular, volumetric CT and MRI studies can provide better anatomic informations regarding internal structure and local tumor spread for pre-operative assessment. Conversely, metabolic imaging using 18F-FDG PET/CT is helpful for lesion characterization differentiating benign from malignant lesion on the basis of intense tracer uptake. The role of PET/MRI is still under investigation. However, final diagnosis still remains surgical even though imaging studies are mandatory for pre-operative patient management.

Romeo, Valeria; Esposito, Alfredo; Maurea, Simone; Camera, Luigi; Mainenti, Pier Paolo; Palmieri, Giovannella; Buonerba, Carlo; Salvatore, Marco

2015-01-01

207

Estimating Patient Dose from X-ray Tube Output Metrics: Automated Measurement of Patient Size from CT Images Enables Large-scale Size-specific Dose Estimates  

PubMed Central

Purpose To test the hypothesis that patient size can be accurately calculated from axial computed tomographic (CT) images, including correction for the effects of anatomy truncation that occur in routine clinical CT image reconstruction. Materials and Methods Institutional review board approval was obtained for this HIPAA-compliant study, with waiver of informed consent. Water-equivalent diameter (DW) was computed from the attenuation-area product of each image within 50 adult CT scans of the thorax and of the abdomen and pelvis and was also measured for maximal field of view (FOV) reconstructions. Linear regression models were created to compare DW with the effective diameter (Deff) used to select size-specific volume CT dose index (CTDIvol) conversion factors as defined in report 204 of the American Association of Physicists in Medicine. Linear regression models relating reductions in measured DW to a metric of anatomy truncation were used to compensate for the effects of clinical image truncation. Results In the thorax, DW versus Deff had an R2 of 0.51 (n = 200, 50 patients at four anatomic locations); in the abdomen and pelvis, R2 was 0.90 (n = 150, 50 patients at three anatomic locations). By correcting for image truncation, the proportion of clinically reconstructed images with an extracted DW within ±5% of the maximal FOV DW increased from 54% to 90% in the thorax (n = 3602 images) and from 95% to 100% in the abdomen and pelvis (6181 images). Conclusion The DW extracted from axial CT images is a reliable measure of patient size, and varying degrees of clinical image truncation can be readily corrected. Automated measurement of patient size combined with CT radiation exposure metrics may enable patient-specific dose estimation on a large scale. © RSNA, 2013 PMID:24086075

Ikuta, Ichiro; Warden, Graham I.; Andriole, Katherine P.; Khorasani, Ramin

2014-01-01

208

Quantitative Diffusion Tensor Imaging Tractography Metrics are Associated with Cognitive Performance Among HIV-Infected Patients  

PubMed Central

There have been many studies examining HIV-infection-related alterations of magnetic resonance imaging (MRI) diffusion metrics. However, examining scalar diffusion metrics ignores the orientation aspect of diffusion imaging, which can be captured with tractography. We examined five different tractography metrics obtained from global tractography maps (global tractography FA, average tube length, normalized number of streamtubes, normalized weighted streamtube length, and normalized total number of tubes generated) for differences between HIV positive and negative patients and the association between the metrics and clinical variables of disease severity. We also examined the relationship between these metrics and cognitive performance across a wide range of cognitive domains for the HIV positive and negative patient groups separately. The results demonstrated a significant difference between the groups for global tractography FA (t=2.13, p= 0.04), but not for any of the other tractography metrics examined (p-value range=0.39 to 0.95). There were also several significant associations between the tractography metrics and cognitive performance (i.e., tapping rates, switching 1 and 2, verbal interference, mazes; r?0.42) for HIV infected patients. In particular, associations were noted between tractography metrics, speed of processing, fine motor control/speed, and executive function for the HIV-infected patients. These findings suggest that tractography metrics capture clinically relevant information regarding cognitive performance among HIV infected patients and suggests the importance of subtle white matter changes in examining cognitive performance. PMID:20503115

Conley, Jared; Paul, Robert H.; Coop, Kathryn; Zhang, Song; Zhou, Wenjin; Laidlaw, David H.; Taylor, Lynn E.; Flanigan, Timothy; Navia, Bradford; Cohen, Ronald; Tashima, Karen

2010-01-01

209

Quantitative diffusion tensor imaging tractography metrics are associated with cognitive performance among HIV-infected patients.  

PubMed

There have been many studies examining HIV-infection-related alterations of magnetic resonance imaging (MRI) diffusion metrics. However, examining scalar diffusion metrics ignores the orientation aspect of diffusion imaging, which can be captured with tractography. We examined five different tractography metrics obtained from global tractography maps (global tractography FA, average tube length, normalized number of streamtubes, normalized weighted streamtube length, and normalized total number of tubes generated) for differences between HIV positive and negative patients and the association between the metrics and clinical variables of disease severity. We also examined the relationship between these metrics and cognitive performance across a wide range of cognitive domains for the HIV positive and negative patient groups separately. The results demonstrated a significant difference between the groups for global tractography FA (t = 2.13, p = 0.04), but not for any of the other tractography metrics examined (p-value range = 0.39 to 0.95). There were also several significant associations between the tractography metrics and cognitive performance (i.e., tapping rates, switching 1 and 2, verbal interference, mazes; r > or = 0.42) for HIV infected patients. In particular, associations were noted between tractography metrics, speed of processing, fine motor control/speed, and executive function for the HIV-infected patients. These findings suggest that tractography metrics capture clinically relevant information regarding cognitive performance among HIV infected patients and suggests the importance of subtle white matter changes in examining cognitive performance. PMID:20503115

Tate, David F; Conley, Jared; Paul, Robert H; Coop, Kathryn; Zhang, Song; Zhou, Wenjin; Laidlaw, David H; Taylor, Lynn E; Flanigan, Timothy; Navia, Bradford; Cohen, Ronald; Tashima, Karen

2010-03-01

210

Indium111-antimyosin images compared with triphenyl tetrazolium chloride staining in a patient six days after myocardial infarction  

Microsoft Academic Search

The results of indium-111 (¹¹¹In) antimyosin imaging during life and the findings on postmortem imaging and triphenyl tetrazolium chloride (TTC) staining of the heart are reported from a patient who received ¹¹¹In-antimyosin on the sixth day following myocardial infarction and died after imaging the next day. The planar images obtained during life showed abnormal ¹¹¹In-antimyosin uptake in the posterior, lateral,

D. Jain; J. C. Crawley; A. Lahiri; E. B. Raftery

1990-01-01

211

Predictive value of longitudinal whole-body magnetic resonance imaging in patients with smoldering multiple myeloma.  

PubMed

Previous studies demonstrated the relevance of focal lesions (FL) in whole-body magnetic resonance imaging (wb-MRI) at the initial workup of patients with smoldering multiple myeloma (SMM). The aim of this study was to assess the effects of longitudinal wb-MRIs on progression into multiple myeloma (MM). Sixty-three patients with SMM were analyzed who received at least two wb-MRIs for follow-up before progression into MM. Radiological progressive disease (MRI-PD) was defined as detection of new FL or increase in diameter of existing FL and a novel or progressive diffuse infiltration. Radiological stable disease (MRI-SD) was defined by no change compared with the prior MRI. Patients were followed-up every 3-6 months, including a serological and clinical evaluation. One Hundred and eighty-two wb-MRIs were analyzed. MRI-PD occurred in 31 patients (49%), and 25 (40%) patients developed MM. MRI-PD was highly significantly associated with progression into MM, regardless of findings at the initial MRI. In multivariate analysis, MRI-PD remained a risk factor, independent of relevant baseline parameters like serum monoclonal protein or ?95% aberrant plasma cells in the bone marrow. Patients with MRI-SD had no higher risk of progression, even when FL were present at the initial MRI. Therefore, MRI is suitable for the follow-up of patients with SMM. PMID:24535407

Merz, M; Hielscher, T; Wagner, B; Sauer, S; Shah, S; Raab, M S; Jauch, A; Neben, K; Hose, D; Egerer, G; Weber, M A; Delorme, S; Goldschmidt, H; Hillengass, J

2014-09-01

212

Dosimetry and Image Quality in Control Studies in Computerised Tomography Realized to Paediatric Patients  

NASA Astrophysics Data System (ADS)

Computerised tomography (CT) is a favourite method of medical diagnosis. Its use has thus increased rapidly throughout the world, particularly in studies relating to children. However to avoid administering unnecessarily high doses of radiation to paediatric patients it is important to have correct dose reference levels to minimize risk. The research is being developed within the public health sector at the Hospital Infantil de México "Dr. Federico Gómez." We measured the entrance surface air kerma (KP) in paediatric patients, during the radiological studies of control in CT (studies of head, thorax and abdomen). Phantom was used to evaluate image quality as the tomograph requires a high resolution image in order to operate at its optimum level.

Hernández, M. R.; Dies, P.; Gamboa-deBuen, I.; Rickards, J.; Ruiz, C.

2008-08-01

213

Dosimetry and Image Quality in Control Studies in Computerised Tomography Realized to Paediatric Patients  

SciTech Connect

Computerised tomography (CT) is a favourite method of medical diagnosis. Its use has thus increased rapidly throughout the world, particularly in studies relating to children. However to avoid administering unnecessarily high doses of radiation to paediatric patients it is important to have correct dose reference levels to minimize risk. The research is being developed within the public health sector at the Hospital Infantil de Mexico 'Dr. Federico Gomez.' We measured the entrance surface air kerma (K{sub P}) in paediatric patients, during the radiological studies of control in CT (studies of head, thorax and abdomen). Phantom was used to evaluate image quality as the tomograph requires a high resolution image in order to operate at its optimum level.

Hernandez, M. R.; Gamboa-deBuen, I. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, A.P. 70-543, Mexico 04510 DF (Mexico); Dies, P. [Hospital Infantil de Mexico 'Dr. Federico Gomez', Dr.Marquez 162, Mexico 06720 DF (Mexico); Rickards, J.; Ruiz, C. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A.P. 20-364, Mexico 01000 DF (Mexico)

2008-08-11

214

Carotid Plaque CT Imaging in Stroke and Non-Stroke Patients  

PubMed Central

OBJECTIVE To identify a set of computed tomography (CT) features of carotid atherosclerotic plaques that is significantly associated with ischemic stroke. METHODS In a cross-sectional study, we retrospectively identified 136 consecutive patients admitted to our emergency department with suspected stroke who underwent a CT-angiogram (CTA) of the cervical and intracranial carotid arteries. CTA studies of the carotid arteries were processed automatically using a custom, CT-based automated computer classifier algorithm that quantitatively assesses a battery of carotid CT features. Acute stroke patients were categorized into "acute carotid stroke patients" and "non-acute carotid stroke patients" independent of carotid wall CT features, using the Causative Classification System for Ischemic Stroke, which includes the neuroradiologist’s review of the imaging studies of the brain parenchyma and of the degree of carotid stenosis, and charted test results (such as EKG and Holter). Univariate followed by multivariate analyses were used to build models to differentiate between these patient groups and to differentiate between the infarct and unaffected sides in the "acute carotid stroke patients". A receiver operating characteristic curve analysis determined which model was most accurate. RESULTS Forty "acute carotid stroke" patients and 50 "non-acute carotid stroke" patients were identified. Multivariate modeling identified a small number of the carotid wall CT features that were significantly associated with acute carotid stroke, including: wall volume, fibrous cap thickness, number and location of lipid clusters, and number of calcium clusters. INTERPRETATION Patients with acute carotid stroke demonstrate significant differences in the appearance of their carotid wall ipsilateral to the side of their infarct, when compared with either non-acute carotid stroke patients or the carotid wall contralateral to the infarct side. PMID:18756475

Wintermark, Max; Arora, Sandeep; Tong, Elizabeth; Vittinghoff, Eric; Lau, Benison C.; Chien, Jeffrey D.; Dillon, William P.; Saloner, David

2008-01-01

215

Segmenting CT prostate images using population and patient-specific statistics for radiotherapy  

SciTech Connect

Purpose: In the segmentation of sequential treatment-time CT prostate images acquired in image-guided radiotherapy, accurately capturing the intrapatient variation of the patient under therapy is more important than capturing interpatient variation. However, using the traditional deformable-model-based segmentation methods, it is difficult to capture intrapatient variation when the number of samples from the same patient is limited. This article presents a new deformable model, designed specifically for segmenting sequential CT images of the prostate, which leverages both population and patient-specific statistics to accurately capture the intrapatient variation of the patient under therapy. Methods: The novelty of the proposed method is twofold: First, a weighted combination of gradient and probability distribution function (PDF) features is used to build the appearance model to guide model deformation. The strengths of each feature type are emphasized by dynamically adjusting the weight between the profile-based gradient features and the local-region-based PDF features during the optimization process. An additional novel aspect of the gradient-based features is that, to alleviate the effect of feature inconsistency in the regions of gas and bone adjacent to the prostate, the optimal profile length at each landmark is calculated by statistically investigating the intensity profile in the training set. The resulting gradient-PDF combined feature produces more accurate and robust segmentations than general gradient features. Second, an online learning mechanism is used to build shape and appearance statistics for accurately capturing intrapatient variation. Results: The performance of the proposed method was evaluated on 306 images of the 24 patients. Compared to traditional gradient features, the proposed gradient-PDF combination features brought 5.2% increment in the success ratio of segmentation (from 94.1% to 99.3%). To evaluate the effectiveness of online learning mechanism, the authors carried out a comparison between partial online update strategy and full online update strategy. Using the full online update strategy, the mean DSC was improved from 86.6% to 89.3% with 2.8% gain. On the basis of full online update strategy, the manual modification before online update strategy was introduced and tested, the best performance was obtained; here, the mean DSC and the mean ASD achieved 92.4% and 1.47 mm, respectively. Conclusions: The proposed prostate segmentation method provided accurate and robust segmentation results for CT images even under the situation where the samples of patient under radiotherapy were limited. A conclusion that the proposed method is suitable for clinical application can be drawn.

Feng, Qianjin; Foskey, Mark; Chen Wufan; Shen Dinggang [Biomedical Engineering College, South Medical University, Guangzhou (China) and Department of Radiology, University of North Carolina, Chapel Hill, North Carolina 27510 (United States); Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Biomedical Engineering College, South Medical University, Guangzhou 510510 (China); Department of Radiology, University of North Carolina, Chapel Hill, North Carolina 27510 (United States)

2010-08-15

216

Diffusion-weighted imaging in noncompressive myelopathies: a 33-patient prospective study  

Microsoft Academic Search

Diffusion-weighted imaging (DWI) is frequently used to differentiate cerebral lesions. The aim of our study was to evaluate\\u000a the diagnostic value of DWI and the measurement of the apparent diffusion coefficient (ADC) in noncompressive myelopathy explorations.\\u000a Thirty-three patients presenting a spinal cord syndrome due to a noncompressive myelopathy underwent spinal cord MRI between\\u000a September 2005 and November 2008. For each

Christophe Marcel; Stéphane Kremer; Jérémy Jeantroux; Frédéric Blanc; Jean-Louis Dietemann; Jérôme De Sèze

2010-01-01

217

Magnetic Resonance Imaging of Brain in Patients with Cirrhotic and Non-Cirrhotic Portal Hypertension  

Microsoft Academic Search

Background Hyperintense signals in the basal ganglia, namely the globus pallidus, have been reported on magnetic resonance imaging (MRI)\\u000a in 70–100% of patients with cirrhosis of the liver. Deposition of paramagnetic substances, particularly manganese (Mn), has\\u000a been reported to be responsible for these hyperintense signals. They are found in cirrhotics with or without overt\\/subclinical\\u000a hepatic encephalopathy. Deposition of Mn has

Kshaunish Das; Paramjeet Singh; Yogesh Chawla; Ajay Duseja; Radha Krishan Dhiman; Sudha Suri

2008-01-01

218

Molecular imaging in patients with mood disorders: a review of PET findings  

Microsoft Academic Search

Mood disorders are chronic, recurrent psychiatric disorders with high morbidity rates that cause severe disability. Researchers\\u000a have used molecular imaging extensively in studies of mood disorders. In this article, we concisely and selectively review\\u000a the major findings of positron emission tomography studies of patients with mood disorders. Specifically, we describe findings\\u000a from cerebral blood flow, cerebral glucose\\/oxygen metabolism, and radioligand

Qiaozhen Chen; Weibo Liu; Huichun Li; Hong Zhang; Mei Tian

2011-01-01

219

Assessment of Cardiovascular Anatomy in Patients with Congenital Heart Disease by Magnetic Resonance Imaging  

Microsoft Academic Search

.   The following discussion addresses the assessment of cardiovascular anatomy in patients with congenital heart disease by\\u000a magnetic resonance (MR). The focus of this review is on the techniques of performing the MR examination. In particular, individual\\u000a pulse sequences are described and illustrated with their strengths and weaknesses. Imaging strategies using the described\\u000a pulse sequences are proposed. The pulse sequences

T. Chung

2000-01-01

220

Regionally Specific Neuronal Pathology in Untreated Patients with Schizophrenia: A Proton Magnetic Resonance Spectroscopic Imaging Study  

Microsoft Academic Search

Background: Proton magnetic resonance spectroscopic imaging (1H-MRSI) studies have reported reductions of N-acetyl aspartate (NAA), a marker of neuronal integrity, in the hippocampal region (HIPPO) and dorsolateral prefrontal cortex (DLPFC) of pharmacologically treated patients with schizophrenia. The purpose of the present study was twofold: to exclude drug treatment as a source of the previous findings and to examine NAA relative

Alessandro Bertolino; Joseph H. Callicott; Igor Elman; Venkata S. Mattay; Gioacchino Tedeschi; Joseph A. Frank; Alan Breier; Daniel R. Weinberger

1998-01-01

221

Patient Dose and Image Quality Evaluation in Common Radiographic Examinations in Sudan  

Microsoft Academic Search

\\u000a Image quality and radiation dose were evaluated in 8radiography rooms in 5 several hospitals in Sudan as part of an International\\u000a Atomic Energy Agency (IAEA) project RAF\\/9\\/033. Entrance Skin Air Kerma (ESAK) was measured in 452 patients in five Sudanese\\u000a hospitals. The six most common X-ray examinations were selected: Chest posterioranterior (PA), abdomen, lumbar spine anterior-posterior\\u000a (AP), lumbar spine lateral

N. A. Ahmed; I. I. Suliman; V. Tsapaki; M. M. Rehani

222

Imaging Lymphatic System in Breast Cancer Patients with Magnetic Resonance Lymphangiography  

PubMed Central

Objective To investigate the feasibility of gadolinium (Gd) contrast-enhanced magnetic resonance lymphangiography (MRL) in breast cancer patients within a typical clinical setting, and to establish a Gd-MRL protocol and identify potential MRL biomarkers for differentiating metastatic from non-metastatic lymph nodes. Materials and Methods 32 patients with unilateral breast cancer were enrolled and divided into 4 groups of 8 patients. Groups I, II, and III received 1.0, 0.5, and 0.3 ml of intradermal contrast; group IV received two 0.5 ml doses of intradermal contrast. MRL images were acquired on a 3.0 T system and evaluated independently by two radiologists for the number and size of enhancing lymph nodes, lymph node contrast uptake kinetics, lymph vessel size, and contrast enhancement patterns within lymph nodes. Results Group III patients had a statistically significant decrease in the total number of enhancing axillary lymph nodes and lymphatic vessels compared to all other groups. While group IV patients had a statistically significant faster time to reach the maximum peak enhancement over group I and II (by 3 minutes), there was no other statistically significant difference between imaging results between groups I, II, and IV. 27 out of 128 lymphatic vessels (21%) showed dilatation, and all patients with dilated lymphatic vessels were pathologically proven to have metastases. Using the pattern of enhancement defects as the sole criterion for identifying metastatic lymph nodes during Gd-MRL interpretation, and using histopathology as the gold standard, the sensitivity and specificity were estimated to be 86% and 95%, respectively. Conclusion Gd-MRL can adequately depict the lymphatic system, can define sentinel lymph nodes, and has the potential to differentiate between metastatic and non-metastatic lymph nodes in breast cancer patients. PMID:23861979

Lu, Qing; Hua, Jia; Kassir, Mohammad M.; Delproposto, Zachary; Dai, Yongming; Sun, Jingyi; Haacke, Mark; Hu, Jiani

2013-01-01

223

Predicting intracerebral hemorrhage by baseline magnetic resonance imaging in stroke patients undergoing systemic thrombolysis  

PubMed Central

Objectives Intracerebral hemorrhage (ICH) remains a serious complication in ischemic stroke patients undergoing systemic thrombolysis. Here, we examined whether the risk of treatment-associated hemorrhage can be predicted from magnetic resonance imaging (MRI) using fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI) within 3 h after symptom onset. Methods In this single-center observational study involving 122 ischemic stroke patients between January 2005 and December 2008, the incidence of FLAIR-positive lesions within diffusion-restricted areas was determined on baseline MRI, which was carried out prior to treatment with tissue plasminogen activator (Actilyse®) within 3 h from symptom onset. The rate of ICH was assessed by computed tomography performed within 24 h after treatment. Relationships between FLAIR-positive lesions, DWI lesion size, proportion of FLAIR/DWI-positive lesions, and occurrence of bleeding were explored. Results Data from 97 patients were evaluated. FLAIR-positive lesions were present in 25 patients (25.8%) and ICH occurred in 32 patients (33.0%). FLAIR-positive lesions were associated with a bleeding rate of 80.0% compared with 16.7% in FLAIR-negative patients (P < 0.001; odds ratio 20.0, positive predictive value 0.8). DWI lesion size was significantly correlated with the rate of ICH (P = 0.001). In contrast, FLAIR/DWI proportion was not associated with ICH (P = 0.788). Conclusions In ischemic stroke patients within 3 h from symptom onset, the existence of FLAIR-positive lesions on pretreatment MRI is significantly associated with an increased bleeding risk due to systemic thrombolysis. Therefore, considering FLAIR-positive lesions on baseline MRI might guide treatment decisions in ischemic stroke. PMID:25040041

Hobohm, C; Fritzsch, D; Budig, S; Classen, J; Hoffmann, K-T; Michalski, D

2014-01-01

224

Motion tracking on elbow tissue from ultrasonic image sequence for patients with lateral epicondylitis.  

PubMed

In this study, Kinesio Tape(R) is used in patients with lateral epicondylitis. The ultrasonic image sequences of elbow are recorded dynamically, and then motion tracking is applied to assist in understanding the effect of the therapy. Motion tracking, based on optical flow method, is used to track certain landmark on the ultrasound image, which is very ambiguous, for estimating the motion of muscle. Hierarchical block tracking technique is proposed to perform this task. The motions with and without Kinesio Taping are compared and can be used as quantitative indicators for the treatment. The experimental results show that Kinesio Taping makes the motion of muscle on the ultrasonic images enlarge. It means that the performance of muscle motion gets improve. PMID:18001897

Liu, Yuh-Hwan; Chen, Shu-Min; Lin, Chi-Yi; Huang, Chung-I; Sun, Yung-Nien

2007-01-01

225

Diffusion tensor imaging and white matter abnormalities in patients with disorders of consciousness  

PubMed Central

Progress in neuroimaging has yielded new powerful tools which, potentially, can be applied to clinical populations, improve the diagnosis of neurological disorders and predict outcome. At present, the diagnosis of consciousness disorders is limited to subjective assessment and objective measurements of behavior, with an emerging role for neuroimaging techniques. In this review we focus on white matter alterations measured using Diffusion Tensor Imaging on patients with consciousness disorders, examining the most common diffusion imaging acquisition protocols and considering the main issues related to diffusion imaging analyses. We conclude by considering some of the remaining challenges to overcome, the existing knowledge gaps and the potential role of neuroimaging in understanding the pathogenesis and clinical features of disorders of consciousness. PMID:25610388

Cavaliere, Carlo; Aiello, Marco; Di Perri, Carol; Fernandez-Espejo, Davinia; Owen, Adrian M.; Soddu, Andrea

2015-01-01

226

Elemental bio-imaging of calcium phosphate crystal deposits in knee samples from arthritic patients  

PubMed Central

Laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) was employed to image deposits of calcium phosphate based crystals in knee cartilage and synovial fluid from arthritic patients. A reaction/collision cell containing hydrogen minimised plasma interferences on calcium and also improved the image quality without significant sensitivity reduction. Areas of high calcium and phosphorus intensities consistent with crystal deposits were observed for both the cartilage and synovial fluid samples. These areas were also characterised by high magnesium and strontium intensities. Distribution patterns of other elements such as copper and sulfur did not correlate with the crystal deposits. Filtered and non-filtered solutions of calcium phosphate crystals grown in synthetic synovial fluid were also imaged as further evidence of crystal deposits. The crystal deposits were detected in the unfiltered solution, and were absent from the filtered solutions. PMID:21305107

Austin, Christine; Hare, Dominic; Rozelle, Andrew L.; Robinson, William H.; Grimm, Rudolf

2012-01-01

227

[Cerebral toxoplasmosis in AIDS patients, CT and MRI images and differential diagnostic problems].  

PubMed

Cranial computed-tomographies (CT) and magnetic resonance imaging (MRI) of 14 patients with AIDS and central nervous system toxoplasmosis (CNST) were reviewed. In spite of the low specificity of CT and MRI findings in CNS mass lesions of AIDS patients, there are some features which have been observed as more typical of CNST, namely: 94.9% of the lesions were round shaped and 94.5% had ring or nodular enhancement; 81.3% of the cases presented multiple lesions; 60.2% of the lesions were localized at the cerebral cortical or corticomedullary junction (100% of the cases showed at least 1 lesion in this localization); 34.6% of the lesions had less than 1cm in diameter.; on nonenhanced CT, 91.3% of the lesions were hypodense.; On T2-weighted MR images, 53.4% of the lesions had at least one hypointense zone on T2-weighted images. The existence of target-shaped lesions with hypointense centre on T2-weighted MR images (29.3% the observed lesions) is also suggestive of CNST, which, to our belief, had not been previously reported and will need confirmation with larger series. The visualization of iso/hyperdense lesions on nonenhanced CT or irregular shape lesions is uncommon in CNST. The finding of a solitary lesion, on CT or MR, it is not, by itself, a good criterion of differential diagnosis. PMID:8638472

Miguel, J; Champalimaud, J L; Borges, A; Chorão, M; Branco, G; Doroana, M; Medina, E

1996-01-01

228

Simultaneous Bilateral Magnetic Resonance Imaging of the Femoral Arteries in Peripheral Arterial Disease Patients  

PubMed Central

Purpose To image the femoral arteries in peripheral arterial disease (PAD) patients using a bilateral receive coil. Materials and Methods An eight-channel surface coil array for bilateral MRI of the femoral arteries at 3T was constructed and evaluated. Results The bilateral array enabled imaging of a 25-cm segment of the superficial femoral arteries (SFA) from the profunda to the popliteal. The array provided improved the signal-to-noise ratio (SNR) at the periphery and similar SNR in the middle of a phantom compared to three other commercially available coils (4-channel torso, quadrature head, whole body). Multicontrast bilateral images of the in vivo SFA with 1 mm inplane resolution made it possible to directly compare lesions in the index SFA to the corresponding anatomical site in the contralateral vessel without repositioning the patient or coil. A set of bilateral time-of-flight, T1-weighted, T2-weighted, and proton density-weighted images was acquired in a clinically acceptable exam time of ?45 minutes. Conclusion The developed bilateral coil is well suited for monitoring dimensional changes in atherosclerotic lesions of the SFA. PMID:21598344

Brown, Ryan; Karmonik, Christof; Brunner, Gerd; Lumsden, Alan; Ballantyne, Christie; Johnson, Shawna; Wang, Yi; Morrisett, Joel

2013-01-01

229

Patient dosimetry for 90Y selective internal radiation treatment based on 90Y PET imaging.  

PubMed

Until recently, the radiation dose to patients undergoing the 90Y selective internal radiation treatment (SIRT) procedure is determined by applying the partition model to 99mTc MAA pretreatment scan. There can be great uncertainty in radiation dose calculated from this approach and we presented a method to compute the 3D dose distributions resulting from 90Y SIRT based on 90Y positron emission tomography (PET) imaging. Five 90Y SIRT treatments were retrospectively analyzed. After 90Y SIRT, patients had 90Y PET/CT imaging within 6 hours of the procedure. To obtain the 3D dose distribution of the patients, their respective 90Y PET images were convolved with a Monte Carlo generated voxel dose kernel. The sensitivity of the PET/CT scanner for 90Y was determined through phantom studies. The 3D dose distributions were then presented in DICOM RT dose format. By applying the linear quadratic model to the dose data, we derived the biologically effective dose and dose equivalent to 2 Gy/fraction delivery, taking into account the spatial and temporal dose rate variations specific for SIRT. Based on this data, we intend to infer tumor control probability and risk of radiation induced liver injury from SIRT by comparison with established dose limits. For the five cases, the mean dose to target ranged from 51.7 ± 28.6 Gy to 163 ± 53.7 Gy. Due to the inhomogeneous nature of the dose distribution, the GTVs were not covered adequately, leading to very low values of tumor control probability. The mean dose to the normal liver ranged from 21.4 ± 30.7 to 36.7 ± 25.9 Gy. According to QUANTEC recommendation, a patient with primary liver cancer and a patient with metastatic liver cancer has more than 5% risk of radiotherapy-induced liver disease (RILD). PMID:24036875

Ng, Sherry C; Lee, Victor H; Law, Martin W; Liu, Rico K; Ma, Vivian W; Tso, Wai Kuen; Leung, To Wai

2013-01-01

230

Dynamic kine magnetic resonance imaging in whiplash patients and in age- and sex-matched controls.  

PubMed

The multitude of symptoms following a whiplash injury has given rise to much discussion because of the lack of objective radiological findings. The ligaments that stabilize the upper cervical spine can be injured. Dynamic kine magnetic resonance imaging (dMRI) may reveal the pathological motion patterns caused by injury to these ligaments. To compare the findings and motion patterns in the upper cervical spine, 25 whiplash trauma patients with longstanding pain, limb symptoms and loss of balance indicating a problem at the level of C0-C2, as well as matched healthy controls were imaged using dMRI. Imaging was performed with an Intera 1.5 T (Philips Healthcare, USA) magnet. A physiotherapist performed the bending and rotation of the upper cervical spine for the subjects to ensure that the movements were limited to the C0-C2 level. An oblique coronal T2- and proton density-weighted sequence and a balanced fast field echo axial sequence were used. The movements between C0-C2 and the signal from the alar ligaments were analyzed. Contact of the transverse ligament and the medulla in rotation was seen in two patients. The signal from the alar ligaments was abnormal in 92% of the patients and in 24% of the control subjects (P<0.0001). Abnormal movements at the level of C1-C2 were more common in patients than in controls (56% versus 20%, P=0.028). Whiplash patients with longstanding symptoms had both more abnormal signals from the alar ligaments and more abnormal movements on dMRI at the C0-C2 level than controls. PMID:20011712

Lindgren, Karl-August; Kettunen, J A; Paatelma, M; Mikkonen, R H M

2009-01-01

231

Expanding Patient Options: Minilaparotomy for Hysterectomy  

MedlinePLUS

... a three- part question. “What’s the rate of conversion? Why not lap” -- I assume that means Lap ... of the final question, “What’s the rate of conversion?” I think they’re asking, how many times ...

232

Mechanically expandable annular seal  

DOEpatents

A mechanically expandable annular reusable seal assembly to form an annular hermetic barrier between two stationary, parallel, and planar containment surfaces is described. A rotatable ring, attached to the first surface, has ring wedges resembling the saw-tooth array of a hole saw. Matching seal wedges are slidably attached to the ring wedges and have their motion restricted to be perpendicular to the second surface. Each seal wedge has a face parallel to the second surface. An annular elastomer seal has a central annular region attached to the seal wedges' parallel faces and has its inner and outer circumferences attached to the first surface. A rotation of the ring extends the elastomer seal's central region perpendicularly towards the second surface to create the fluid tight barrier. A counter rotation removes the barrier. 6 figs.

Gilmore, R.F.

1983-07-19

233

Mechanically expandable annular seal  

DOEpatents

A mechanically expandable annular reusable seal assembly to form an annular hermetic barrier between two stationary, parallel, and planar containment surfaces. A rotatable ring, attached to the first surface, has ring wedges resembling the saw-tooth array of a hole saw. Matching seal wedges are slidably attached to the ring wedges and have their motion restricted to be perpendicular to the second surface. Each seal wedge has a face parallel to the second surface. An annular elastomer seal has a central annular region attached to the seal wedges' parallel faces and has its inner and outer circumferences attached to the first surface. A rotation of the ring extends the elastomer seal's central region perpendicularly towards the second surface to create the fluidtight barrier. A counterrotation removes the barrier.

Gilmore, Richard F. (Kennewick, WA)

1983-01-01

234

White Matter Changes in Patients with Amnestic Mild Cognitive Impairment Detected by Diffusion Tensor Imaging  

PubMed Central

Compared to normal aging adults, individuals with amnestic mild cognitive impairment (aMCI) have significantly increased risk for progressing into Alzheimer’s disease (AD). Autopsy studies found that most of the brains of aMCI cases showed anatomical features associated with AD pathology. The recent development of non-invasive neuroimaging technique, such as diffusion tensor imaging (DTI), makes it possible to investigate the microstructures of the cerebral white matter in vivo. We hypothesized that disrupted white matter (WM) integrity existed in aMCI. So we used DTI technique, by measuring fractional anisotropy (FA) and mean diffusivity (MD), to test the brain structures involved in patients with aMCI. DTI scans were collected from 40 patients with aMCI, and 28 normal controls (NC). Tract-based spatial statistics (TBSS) analyses of whole-brain FA and MD images in each individual and group comparisons were carried out. Compared to NC, aMCI patients showed significant FA reduction bilaterally, in the association and projection fibers of frontal, parietal, and temporal lobes, corpus callosum, bilateral corona radiation, right posterior thalamic radiation and right sagittal stratum. aMCI patients also showed significantly increased MD widespreadly in the association and projection fibers of frontal, parietal and temporal lobes, and corpus callosum. Assessment of the WM integrity of the frontal, parietal, temporal lobes, and corpus callosum by using DTI measures may aid early diagnosis of aMCI. PMID:23555673

Xia, Shugao; Jia, Longfei; Guo, Yanqin; Zhao, Zhilian; Li, Xiaobo; Han, Ying; Jia, Jianping

2013-01-01

235

Motor co-activation in siblings of patients with juvenile myoclonic epilepsy: an imaging endophenotype?  

PubMed Central

Juvenile myoclonic epilepsy is a heritable idiopathic generalized epilepsy syndrome, characterized by myoclonic jerks and frequently triggered by cognitive effort. Impairment of frontal lobe cognitive functions has been reported in patients with juvenile myoclonic epilepsy and their unaffected siblings. In a recent functional magnetic resonance imaging study we reported abnormal co-activation of the motor cortex and increased functional connectivity between the motor system and prefrontal cognitive networks during a working memory paradigm, providing an underlying mechanism for cognitively triggered jerks. In this study, we used the same task in 15 unaffected siblings (10 female; age range 18–65 years, median 40) of 11 of those patients with juvenile myoclonic epilepsy (six female; age range 22–54 years, median 35) and compared functional magnetic resonance imaging activations with 20 age- and gender-matched healthy control subjects (12 female; age range 23–46 years, median 30.5). Unaffected siblings showed abnormal primary motor cortex and supplementary motor area co-activation with increasing cognitive load, as well as increased task-related functional connectivity between motor and prefrontal cognitive networks, with a similar pattern to patients (P < 0.001 uncorrected; 20-voxel threshold extent). This finding in unaffected siblings suggests that altered motor system activation and functional connectivity is not medication- or seizure-related, but represents a potential underlying mechanism for impairment of frontal lobe functions in both patients and siblings, and so constitutes an endophenotype of juvenile myoclonic epilepsy. PMID:25001494

Wandschneider, Britta; Centeno, Maria; Vollmar, Christian; Symms, Mark; Thompson, Pamela J.; Duncan, John S.

2014-01-01

236

Motor co-activation in siblings of patients with juvenile myoclonic epilepsy: an imaging endophenotype?  

PubMed

Juvenile myoclonic epilepsy is a heritable idiopathic generalized epilepsy syndrome, characterized by myoclonic jerks and frequently triggered by cognitive effort. Impairment of frontal lobe cognitive functions has been reported in patients with juvenile myoclonic epilepsy and their unaffected siblings. In a recent functional magnetic resonance imaging study we reported abnormal co-activation of the motor cortex and increased functional connectivity between the motor system and prefrontal cognitive networks during a working memory paradigm, providing an underlying mechanism for cognitively triggered jerks. In this study, we used the same task in 15 unaffected siblings (10 female; age range 18-65 years, median 40) of 11 of those patients with juvenile myoclonic epilepsy (six female; age range 22-54 years, median 35) and compared functional magnetic resonance imaging activations with 20 age- and gender-matched healthy control subjects (12 female; age range 23-46 years, median 30.5). Unaffected siblings showed abnormal primary motor cortex and supplementary motor area co-activation with increasing cognitive load, as well as increased task-related functional connectivity between motor and prefrontal cognitive networks, with a similar pattern to patients (P < 0.001 uncorrected; 20-voxel threshold extent). This finding in unaffected siblings suggests that altered motor system activation and functional connectivity is not medication- or seizure-related, but represents a potential underlying mechanism for impairment of frontal lobe functions in both patients and siblings, and so constitutes an endophenotype of juvenile myoclonic epilepsy. PMID:25001494

Wandschneider, Britta; Centeno, Maria; Vollmar, Christian; Symms, Mark; Thompson, Pamela J; Duncan, John S; Koepp, Matthias J

2014-09-01

237

Elderly depression diagnostic of diabetic patients by brain tissue pulsatility imaging  

NASA Astrophysics Data System (ADS)

Pulsatile motion of brain parenchyma results from cardiac and breathing cycles and consists in a rapid displacement in systole, with slow diastolic recovery. Based on the vascular depression concept and recent studies where a correlation was found between cerebral haemodynamics and depression in the elderly, we emitted the hypothesis that tissue brain motion due to perfusion is correlated to elderly depression associated with cardiovascular risk factors. Tissue Pulsatlity Imaging (TPI) is a new ultrasound technique developed firstly at the University of Washington to assess the brain tissue motion. We used TPI technique to measure the brain displacement of two groups of elderly patients with diabetes as a vascular risk factor. The first group is composed of 11 depressed diabetic patients. The second group is composed of 12 diabetic patients without depressive symptoms. Transcranial acquisitions were performed with a 1.8 MHz ultrasound phased array probe through the right temporal bone window. The acquisition of six cardiac cycles was realized on each patient with a frame rate of 23 frames/s. Displacements estimation was performed by off-line analysis. A significant decrease in brain pulsatility was observed in the group of depressed patients compared to the group of non depressed patients. Mean displacement magnitude was about 44±7 ?m in the first group and 68±13 ?m in the second group.

Hachemi, Mélouka Elkateb; Remeniéras, Jean-pierre; Desmidt, Thomas; Camus, Vincent; Tranquart, François

2010-01-01

238

Management of patients with thyroid carcinoma: Application of thallium-201 scintigraphy and magnetic resonance imaging  

SciTech Connect

Thyroid carcinoma has the ability to concentrate radioiodine, an attribute that can be used both for detection of thyroid cells and for treatment. Unfortunately, however, radioiodine uptake is not observed in all patients and a radioiodine scan requires that the patient be rendered hypothyroid for 4-6 wk. In the present study, we analyzed the utility of thallium-201 scanning and the usefulness of magnetic resonance imaging (MRI) in the detection of thyroid cancer. Nineteen patients with thyroid cancer had a total of 24 radioiodine scans, 33 thallium scans, and 10 MRI examinations. Of the 19 patients in the study, 17 had differentiated thyroid carcinoma. In these 17 cases, all paired studies were concordant for the presence (n = 7) or absence (n = 10) of disease. However, in one case (Patient 10), the {sup 201}Tl studies showed far more extensive disease than was observed on the {sup 131}I scan. Thyroid cancer was also detected on seven MRI studies. In summary, thallium and MRI scans are adjunctive techniques to radioiodine scanning that can either confirm the presence of neck bed activity, residual disease or metastatic cancer and may delineate tumor deposits not detected by radioiodine scanning. Thallium may be capable of detecting tumor deposits even while a patient remains euthyroid.

Burman, K.D.; Anderson, J.H.; Wartofsky, L.; Mong, D.P.; Jelinek, J.J. (Walter Reed Army Medical Center, Washington, DC (USA))

1990-12-01

239

Imaging of the common bile duct in patients undergoing laparoscopic cholecystectomy.  

PubMed Central

Options for managing the common bile duct during laparoscopic cholecystectomy include routine peroperative cholangiography and selected preoperative endoscopic retrograde cholangiopancreatography (ERCP). The use of these methods was reviewed in 350 patients with symptomatic gall stones referred for laparoscopic cholecystectomy. Unit A (n = 114) performed routine cystic duct cholangiography but undertook preoperative ERCP in patients at very high risk of duct stones only; unit B (n = 236) performed selected preoperative ERCP on the basis of known risk factors for duct stones. The detection rate for common bile duct stones was similar for units A and B (16% v 20%). In unit A, five of seven patients who had preoperative ERCP had duct stones. Operative cholangiography was technically successful in 90% of patients and duct stones were confidently identified in 13, one of whom went on to immediate open duct exploration. Postoperative ERCP identified duct stones in only four patients, indicating spontaneous passage in eight. In unit B, preoperative ERCP was undertaken in 76 of 236 (32%) patients and duct stones were identified in 47 (20%). Duct clearance was successful in 42 (18%) but failed in five (2%), necessitating elective open duct exploration. Both protocols for imaging the common bile duct worked well and yielded satisfactory short term results. PMID:8063230

Hainsworth, P J; Rhodes, M; Gompertz, R H; Armstrong, C P; Lennard, T W

1994-01-01

240

Image Analyzer Study of the Skin in Patients With Morbid Obesity and Massive Weight Loss  

PubMed Central

Objective: Studies in literature on skin of patients with massive weight loss are limited and somehow conflicting in their results. The aim of this study was to quantitatively assess the skin change after massive weight loss. Method: This study was performed on 30 patients from whom skin biopsies were taken from the skin excised during operations, divided into 3 main groups. The first included patients who were undergoing cosmetic contouring procedures without history of massive weight loss. The second included patients with morbid obesity, who were undergoing bariatric surgery. The third included patients with massive weight loss submitted to cosmetic contouring procedures after stable weight reduction for 6 months. Biopsies were taken from the skin for histological testing. Hematoxylin and Eosin, Mallory, and Aldehyde fuchsin Stains were used to assess the skin collagen and elastic fibers. For quantitative assessment, the Image Analyzer System (Leica Q 500 MC program) was employed. Tensile tests were applied to skin samples using (Instron 5500R) Universal testing machine to measure the skin tensile strength to determine the maximum stress (Burst strength) that skin can induce before damage. Results: Collagen was significantly thinner in massive weight loss group in both papillary and reticular dermis and significantly less dense in reticular dermis with damage to the elastic fiber network. Conclusion: The skin of the patients with massive weight loss is weak due to lower density and thickness of collagen fibers and damage to its elastic fibers.

Sami, Khaled; Moussa, Manal; Abbas, Alaa; Mahmoud, Amr

2015-01-01

241

An adaptive patient specific deformable registration for breast images of positron emission tomography and magnetic resonance imaging using finite element approach  

NASA Astrophysics Data System (ADS)

A patient specific registration model based on finite element method was investigated in this study. Image registration of Positron Emission Tomography (PET) and Magnetic Resonance imaging (MRI) has been studied a lot. Surface-based registration is extensively applied in medical imaging. We develop and evaluate a registration method combine surface-based registration with biomechanical modeling. .Four sample cases of patients with PET and MRI breast scans performed within 30 days were collected from hospital. K-means clustering algorithm was used to segment images into two parts, which is fat tissue and neoplasm [2]. Instead of placing extrinsic landmarks on patients' body which may be invasive, we proposed a new boundary condition to simulate breast deformation during two screening. Then a three dimensional model with meshes was built. Material properties were assigned to this model according to previous studies. The whole registration was based on a biomechanical finite element model, which could simulate deformation of breast under pressure.

Xue, Cheng; Tang, Fuk-Hay

2014-03-01

242

Investigating novel patient bed designs for use in a hybrid dual modality dedicated 3D breast imaging system  

NASA Astrophysics Data System (ADS)

A hybrid SPECT-CT system for dedicated 3D breast cancer imaging (mammotomography) is in development. Using complex 3D imaging acquisition trajectories, the versatile integrated system will be capable of contouring and imaging an uncompressed breast suspended in a 3D volume located below a radio-opaque patient bed, providing co-registered volumetric anatomical and functional information. This study examines tradeoffs involved in the design of the patient bed to satisfy concomitant and competing technical and ergonomic requirements specific to this imaging paradigm. The complementary source-detector arrangement of the CT system is geometrically more restrictive than that of the single detector SPECT system. Additionally, the compact dimensions and size of the CT system components (primarily the x-ray tube) are key constraints on the bed design and so the focus is concentrated there. Using computer-aided design software, several design geometry options are examined to simultaneously consider and optimize the following parameters: image magnification, imaged breast volume, azimuthal imaging span, and patient comfort. Several CT system source to image distances are examined (55-80cm), as well as axial patient tilt up to 35°. An optimal patient bed design for a completely under-bed hybrid imaging system was determined. A 60cm SID, magnification factor of ~1.5, and patient bed angled at ~15° provided the optimal dimensions. Additional bed dimensions allow the CT projection beam to nearly entirely image the chest wall, however at the cost of reduced angular sampling for CT. Acquired x-ray mammotomographic image data is used to assess the feasibility of this reduced angle acquisition approach.

Crotty, Dominic J.; Madhav, Priti; McKinley, Randolph L.; Tornai, Martin P.

2007-03-01

243

Retrospective review of image quality of CT in polytrauma patients: comparison of patients scanned using a scoop stretcher and without a scoop stretcher.  

PubMed

Increasingly pre-hospital trauma management involves transfer of patients using a scoop stretcher; a number of computed tomography (CT) compatible scoops have recently appeared on the market. We sought to evaluate any differences in image quality in polytrauma patients scanned in a scoop stretcher. CT studies of 234 consecutive patients presenting between December 2011 and August 2012 at our regional level 1 tertiary trauma centre were retrospectively reviewed. Patients were allocated into two groups: those scanned with a scoop stretcher and without. CTs were reviewed by a consultant radiologist and two senior radiology trainees and graded separately for quality/artefact. A scale of 1-5 was employed: 1-uninterpretable, 2-borderline image quality, 3-acceptable, 4-good, 5-excellent. A total of 128 (54.7 %) patients were scanned in a scoop stretcher and 106 (45.3 %) were scanned without, 183 males and 51 females (average age, 46 (16-94) years; SD, 20). The average quality grading for the patients scanned in the scoop was 4.64 compared to 4.68 in those without the scoop. There was no significant grading difference between the groups, consultant (p?=?0.096) and trainees (p?=?0.782). No artefacts were attributable to the scoop stretcher 0/128 (0 %). Following our experience, the use of scoop stretchers is recommended for efficient, safe and practical management of trauma patients and in terms of imaging, with no detrimental effect on image quality. PMID:23978869

Modi, Sachin; Gadvi, Rakesh; Yeo, David; Galea-Soler, Sandro

2014-02-01

244

Electrophysiological and diffusion tensor imaging evidence of delayed corollary discharges in patients with schizophrenia  

PubMed Central

Patients with schizophrenia (SZ) characteristically exhibit supranormal levels of cortical activity to self-induced sensory stimuli, ostensibly because of abnormalities in the neural signals (corollary discharges, CDs) normatively involved in suppressing the sensory consequences of self-generated actions. The nature of these abnormalities is unknown. This study investigated whether SZ patients experience CDs that are abnormally delayed in their arrival at the sensory cortex. Twenty-one patients with SZ and 25 matched control participants underwent electroencephalography (EEG). Participants’ level of cortical suppression was calculated as the amplitude of the N1 component evoked by a button press-elicited auditory stimulus, subtracted from the N1 amplitude evoked by the same stimulus presented passively. In the three experimental conditions, the auditory stimulus was delivered 0, 50 or 100 ms subsequent to the button-press. Fifteen SZ patients and 17 healthy controls (HCs) also underwent diffusion tensor imaging (DTI), and the fractional anisotropy (FA) of participants’ arcuate fasciculus was used to predict their level of cortical suppression in the three conditions. While the SZ patients exhibited subnormal N1 suppression to undelayed, self-generated auditory stimuli, these deficits were eliminated by imposing a 50-ms, but not a 100-ms, delay between the button-press and the evoked stimulus. Furthermore, the extent to which the 50-ms delay normalized a patient’s level of N1 suppression was linearly related to the FA of their arcuate fasciculus. These data suggest that SZ patients experience temporally delayed CDs to self-generated auditory stimuli, putatively because of structural damage to the white-matter (WM) fasciculus connecting the sites of discharge initiation and destination. PMID:20663254

Whitford, T. J.; Mathalon, D. H.; Shenton, M. E.; Roach, B. J.; Bammer, R.; Adcock, R. A.; Bouix, S.; Kubicki, M.; De Siebenthal, J.; Rausch, A. C.; Schneiderman, J. S.; Ford, J. M.

2013-01-01

245

Assessment of Diffuse Myocardial Fibrosis by Using MR Imaging in Asymptomatic Patients with Aortic Stenosis.  

PubMed

Purpose To assess whether native T1 mapping provides noninvasive estimation of diffuse myocardial fibrosis and whether it correlates with subclinical myocardial dysfunction in asymptomatic patients with aortic stenosis (AS). Materials and Methods The local institutional review board approved the study, and all patients gave informed consent. Eighty asymptomatic patients with moderate or severe AS and normal left ventricular (LV) ejection fraction (mean age, 67 years; range, 31-81 years) and 15 sex-matched control subjects (mean age, 33 years; range, 23-41 years) were prospectively enrolled. Patients underwent two-dimensional echocardiography, speckle tracking imaging, and cardiac 3.0-T magnetic resonance (MR) imaging, including mapping of T1 relaxation time by using the modified Look-Locker inversion-recovery sequence. Correlations between native T1 values and the degree of diffuse fibrosis in myocardial specimens obtained during aortic valve replacement surgery were analyzed in a subset of 20 patients. Correlations between parameters of myocardial function and structure and native T1 values were assessed with Pearson correlation coefficients. Results Native T1 values correlated well with the degree of diffuse myocardial fibrosis in intraoperative myocardial biopsy specimens (r = 0.777, P < .001) and differed significantly between patients with AS and control subjects (1208 msec ± 45 vs 1169 msec ± 21, P < .001). LV volumes and mass differed significantly according to AS groups, categorized by T1 tertiles (all P < .001), as well as degree of AS severity (0.55 cm(2)/m(2) ± 0.14 for lowest native T1 tertile, 0.46 cm(2)/m(2) ± 0.12 for middle native T1 tertile, and 0.45 cm(2)/m(2) ± 0.13 for highest native T1 tertile [P = .008] for indexed aortic valve area at echocardiography). Native T1 correlated significantly with global longitudinal strain measured with two-dimensional speckle tracking imaging (r = 0.598, P < .001), e' velocity (r = -0.437, P < .001), and indexed left atrial volume (r = 0.475, P < .001). Conclusion Native T1 mapping provides a noninvasive estimation of diffuse myocardial fibrosis and correlates with subclinical myocardial dysfunction in asymptomatic patients with AS. © RSNA, 2014 Online supplemental material is available for this article. PMID:25251584

Lee, Seung-Pyo; Lee, Whal; Lee, Joo Myung; Park, Eun-Ah; Kim, Hyung-Kwan; Kim, Yong-Jin; Sohn, Dae-Won

2015-02-01

246

Magnetic Resonance Imaging of the Ear for Patient-Specific Reconstructive Surgery  

PubMed Central

Introduction Like a fingerprint, ear shape is a unique personal feature that should be reconstructed with a high fidelity during reconstructive surgery. Ear cartilage tissue engineering (TE) advantageously offers the possibility to use novel 3D manufacturing techniques to reconstruct the ear, thus allowing for a detailed auricular shape. However it also requires detailed patient-specific images of the 3D cartilage structures of the patient’s intact contralateral ear (if available). Therefore the aim of this study was to develop and evaluate an imaging strategy for acquiring patient-specific ear cartilage shape, with sufficient precision and accuracy for use in a clinical setting. Methods and Materials Magnetic resonance imaging (MRI) was performed on 14 volunteer and six cadaveric auricles and manually segmented. Reproducibility of cartilage volume (Cg.V), surface (Cg.S) and thickness (Cg.Th) was assessed, to determine whether raters could repeatedly define the same volume of interest. Additionally, six cadaveric auricles were harvested, scanned and segmented using the same procedure, then dissected and scanned using high resolution micro-CT. Correlation between MR and micro-CT measurements was assessed to determine accuracy. Results Good inter- and intra-rater reproducibility was observed (precision errors <4% for Cg.S and <9% for Cg.V and Cg.Th). Intraclass correlations were good for Cg.V and Cg.S (>0.82), but low for Cg.Th (<0.23) due to similar average Cg.Th between patients. However Pearson’s coefficients showed that the ability to detect local cartilage shape variations is unaffected. Good correlation between clinical MRI and micro-CT (r>0.95) demonstrated high accuracy. Discussion and Conclusion This study demonstrated that precision and accuracy of the proposed method was high enough to detect patient-specific variation in ear cartilage geometry. The present study provides a clinical strategy to access the necessary information required for the production of 3D ear scaffolds for TE purposes, including detailed patient-specific shape. Furthermore, the protocol is applicable in daily clinical practice with existing infrastructure. PMID:25144306

Nimeskern, Luc; Feldmann, Eva-Maria; Kuo, Willy; Schwarz, Silke; Goldberg-Bockhorn, Eva; Dürr, Susanne; Müller, Ralph; Rotter, Nicole; Stok, Kathryn S.

2014-01-01

247

Expanding the frontiers of  

E-print Network

BREEDS SAVED ALCUIN'S LOST LIBRARY IBM chief launches new era for Computer Science #12;T he forthcoming Grenville, Pro-Vice-Chancellor for Students CONTENTS Cover image: The new Department of Computer Science and their overview of sports and societies. Students know what students enjoy doing and in responding to a `social

248

Regional myocardial velocity imaged by magnetic resonance in patients with ischaemic heart disease.  

PubMed Central

OBJECTIVE--To assess the pattern of global and regional left ventricular long axis motion during early diastole in patients with ischaemic heart disease with and without myocardial infarction using magnetic resonance velocity mapping. DESIGN--Prospective study of 26 patients with a history of myocardial infarction (age 29-78, mean 55 years) and 21 patients with coronary artery disease without infarction (age range 39-71, mean 58 years). Values were compared with a control group (19 controls, age 35-76, mean 52 years) with a low likelihood of cardiovascular disease. RESULTS--Regional long axis velocity varied with time and position around the ventricle. All measurements were taken at the time of maximum early diastolic long axis velocity. Patients with coronary artery disease without infarction had lower values for maximum (mean (SD)) (99 (30) v 125 (33) mm/s, P < 0.05) and mean peak early diastolic wall motion (63 (13) v 82 (22) mm/s, P < 0.05) than controls. The coefficient of variation showed greater inhomogeneity of relaxation in patients than in controls (38 (18)% v 27 (10)%). All values were lower in patients with previous infarction than in patients with coronary artery disease without infarction and normal subjects. In patients with previous myocardial infarction the maximum (mean (SD)) early diastolic velocity was 80 (22) mm/s (P < 0.01 compared with controls and P < 0.05 compared with patients without infarction) and the mean (SD) velocity was 47 (18) mm/s (P < 0.01 compared with controls). The coefficient of variation was greater (52 (33)%) than for controls (P < 0.05) and patients with coronary artery disease without infarction. 18 of 26 patients with previous myocardial infarction and 13 of 21 patients with coronary artery disease without infarction had regional abnormalities corresponding to areas of fixed or reversible ischaemia on exercise electrocardiography or thallium myocardial perfusion tomography. CONCLUSIONS--Magnetic resonance velocity mapping can be used to assess regional long axis myocardial velocity. Ischaemic heart disease causes alterations in the patterns of left ventricular long axis velocity during early diastole. Images PMID:7833190

Karwatowski, S P; Mohiaddin, R H; Yang, G Z; Firmin, D N; St John Sutton, M; Underwood, S R

1994-01-01

249

Can Breast Cancer Molecular Subtype Help to Select Patients for Preoperative MR Imaging?  

PubMed

Purpose To assess whether breast cancer molecular subtype classified by surrogate markers can be used to predict the extent of clinically relevant disease with preoperative breast magnetic resonance (MR) imaging. Materials and Methods In this HIPAA-compliant, institutional review board-approved study, informed consent was waived. Preoperative breast MR imaging reports from 441 patients were reviewed for multicentric and/or multifocal disease, lymph node involvement, skin and/or nipple invasion, chest wall and/or pectoralis muscle invasion, or contralateral disease. Pathologic reports were reviewed to confirm the MR imaging findings and for hormone receptors (estrogen and progesterone subtypes), human epidermal growth factor receptor type 2 (HER2 subtype), tumor size, and tumor grade. Surrogates were used to categorize tumors by molecular subtype: hormone receptor positive and HER2 negative (luminal A subtype); hormone receptor positive and HER2 positive (luminal B subtype); hormone receptor negative and HER2 positive (HER2 subtype); hormone receptor negative and HER2 negative (basal subtype). All patients included in the study had a histologic correlation with MR imaging findings or they were excluded. ?(2) analysis was used to compare differences between subtypes, with multivariate logistic regression analysis used to assess for variable independence. Results Identified were 289 (65.5%) luminal A, 45 (10.2%) luminal B, 26 (5.9%) HER2, and 81 (18.4%) basal subtypes. Among subtypes, significant differences were found in the frequency of multicentric and/or multifocal disease (luminal A, 27.3% [79 of 289]; luminal B, 53.3% [24 of 45]; HER2, 65.4% [17 of 26]; basal, 27.2% [22 of 81]; P < .001) and lymph node involvement (luminal A, 17.3% [50 of 289]; luminal B, 35.6% [26 of 45]; HER2, 34.6% [nine of 26]; basal 24.7% [20 of 81]; P = .014). Multivariate analysis showed that molecular subtype was independently predictive of multifocal and/or multicentric disease. Conclusion Preoperative breast MR imaging is significantly more likely to help detect multifocal and/or multicentric disease and lymph node involvement in luminal B and HER2 molecular subtype breast cancers. Molecular subtype may help to select patients for preoperative breast MR imaging. © RSNA, 2014. PMID:25325325

Grimm, Lars J; Johnson, Karen S; Marcom, P Kelly; Baker, Jay A; Soo, Mary S

2015-02-01

250

A comparative study of coping skills and body image: Mastectomized vs. lumpectomized patients with breast carcinoma  

PubMed Central

Background: The diagnosis of breast cancer encompasses not only physical, but also social and psychological implications because of the importance of the breast in a woman's body image, sexuality and motherhood. Women may experience a range of concerns and fears including physical appearance and disfigurement, the uncertainty about recurrence and the fear of death. There are no Indian studies on this subject. Aim: This study explores the various concerns of mastectomized and lumpectomized (breast conserved) patients, determines the coping mechanisms employed and the resolution of concerns. The levels of anxiety and depression in both groups were also studied. Methods: Seventy-five patients with breast carcinoma (50 mastectomized and 25 lumpectomized) were evaluated. The concern and coping checklist of Devlen was used. The severity of anxiety and depression was measured using the Hospital Anxiety and Depression Scale (HADS). Results: Body image or disfigurement was a concern only in the mastectomized group. Concerns were equally resolved between the two groups except for sexual role and performance, wherein the concern was resolved to a lesser extent in the mastectomized group. Coping strategies employed were effective in the resolution of concerns except for sexual role and performance, and recurrence or relapse. No statistically significant difference was found in the depression and anxiety levels of the two groups. Conclusion: Concern regarding sexual role and performance was resolved to a lesser extent in the mastectomized group. Specific psychological intervention is necessary to enhance coping strategies with regard to concerns of body image, and sexual role and performance. PMID:20711305

Mahapatro, Fiona; Parkar, Shubhangi R.

2005-01-01

251

Incidental Findings on Simulation CT Images for Adjuvant Radiotherapy in Breast Cancer Patients.  

PubMed

We designed this study to evaluate the incidence of incidental findings on computed tomography (CT) scan implemented as simulation for adjuvant radiotherapy in breast cancer patients and to emphasize the need for careful review of simulation CT images before planning radiotherapy. A Resident and attending radiation oncologists retrospectively reviewed the medical records and simulation CT images of 776 patients treated with adjuvant radiotherapy at Samsung Medical Center during 2008. Previously undetected abnormal findings on simulation CT images were defined as incidental findings and interpreted by diagnostic radiologist. If the incidental findings required further evaluation or follow-up, they were defined as indeterminate findings. If subsequent cancers were diagnosed according incidental findings, they were defined as malignancy-related findings. There were 81 indeterminate findings (10.8%) including thyroid nodule, solitary pulmonary nodule, mediastinal lymph node, supraclavicular or axillary lymph node. Among them, there were nine malignancy-related findings (1.3%), including four thyroid cancers, three lung metastases, one primary lung cancer, and one axillary lymph node recurrence. The incidence of incidental findings in this study was low, but some of the findings were related to malignancy. Radiation oncologists should be alert to incidental findings on simulation CT, and incidental findings should be evaluated by diagnostic radiologists. PMID:24645749

Park, J S; Choi, D H; Huh, S J; Park, W; Nam, S J; Lee, J E; Kil, W H; Lee, K S

2014-03-17

252

Effectiveness of adherence therapy in patients with early psychosis: a mirror image study.  

PubMed

In patients with early psychosis, medication non-adherence is associated with more frequent relapse. Observational studies have reported that up to 60% of patients fail to take medication as prescribed. This study aimed to establish the effectiveness of adherence therapy (AT) training for two multidisciplinary early intervention in psychosis (EIIP) teams in preventing relapse in their patients. This intervention involved six 1-day team AT training sessions delivered monthly over a 6-month period. Participants were patients with early psychosis who were on the caseload of the EIIP teams during the study period. A mirror-image design was used, comparing clinician ratings of relapse in the year preceding training (year 0) and the subsequent year (year 1). Results showed that in year 0, the mean number of relapses was 0.96 (standard deviation (SD) = 1.10). During year 1, relapses reduced significantly (P < 0.01) to 0.34 (SD = 0.64). No unexpected effects of training were reported. A thematic analysis of staff views of training, and service users' views of their care received from EIIP teams, was also completed. Challenges in faithfully incorporating AT skills into practice were reported. In conclusion, AT training coincided with reductions in relapse rates in patients receiving services from an EIIP team, but no other changes in outcomes were detected. PMID:22697292

Brown, Ellie; Gray, Richard; Jones, Martin; Whitfield, Simon

2013-02-01

253

Image-Guided Hypofractionated Radiotherapy in Low-Risk Prostate Cancer Patients  

PubMed Central

Aim. To evaluate efficacy and toxicity of image-guided hypofractionated radiotherapy (HFRT) in the treatment of low-risk prostate cancer. Outcomes and toxicities of this series of patients were compared to another group of 32 low-risk patients treated with conventional fractionation (CFRT). Methods. Fifty-nine patients with low-risk prostate cancer were analysed. Total dose for the prostate and proximal seminal vesicles was 60?Gy delivered in 20 fractions. Results. The median follow-up was 30 months. The actuarial 4-year overall survival, biochemical free survival, and disease specific survival were 100%, 97.4%, and 97.4%, respectively. Acute grade 1-2 gastrointestinal (GI) and genitourinary (GU) toxicity rates were 11.9% and 40.7%, respectively. Grade 1?GI and GU late toxicity rates were 8.5% and 13.6%, respectively. No grade ?2 late toxicities were recorded. Acute grade 2-3?GU toxicity resulted significantly lower (P = 0.04) in HFRT group compared to the CFRT group. The cumulative 4-year incidence of grade 1-2?GU toxicity was significantly higher (P < 0.001) for HFRT patients. Conclusions. Our study demonstrated that hypofractionated regimen provided excellent biochemical control in favorable risk prostate cancer patients. The incidence of GI and GU toxicity was low. However, HFRT presented higher cumulative incidence of low-grade late GU toxicity than CFRT. PMID:24864248

Valeriani, Maurizio; Carnevale, Alessia; Bonome, Paolo; Montalto, Adelaide; Nicosia, Luca; Osti, Mattia F.; De Sanctis, Vitaliana; Minniti, Giuseppe; Maurizi Enrici, Riccardo

2014-01-01

254

Promoting medical tourism to India: messages, images, and the marketing of international patient travel.  

PubMed

The practice of medical tourism depends on successfully informing potential patients about procedure options, treatment facilities, tourism opportunities, travel arrangements, and destination countries. The promotion of medical tourism includes a wide range of marketing materials such as flyers, booklets, and websites. Yet, there is a paucity of knowledge about the dissemination, content, and reception of these promotional materials. Drawing on a thematic content analysis of the promotional print material distributed at the first medical tourism trade show in Canada in 2009, the main purpose of this article is to identify and understand the messages and images that companies use to market India as a global destination. While researchers and news media frequently cite low cost procedures as a key determinant for international patient travel, particularly to developing nations, our analysis reveals few low cost-related images or messages in the promotional materials distributed at the trade show. To help explain this surprising disjuncture, we consider four related issues: (1) promotional materials may be designed to be circulated amongst potential patients' concerned family and friends who privilege knowing about things such as the use of advanced technologies; (2) developing nations need to portray safe and advanced treatment facilities in order to dispel potential patients' suspicions that their medical care is inferior; (3) companies may avoid making cost saving claims that cannot be fulfilled for all of their international patients, especially those traveling from developing nations; and (4) messages of low cost may detract from and even undermine messages about quality. We conclude by identifying numerous avenues for future research by social and health scientists, and by considering the implications of our findings for existing knowledge gaps and debates within health geography specifically. PMID:21310519

Crooks, Valorie A; Turner, Leigh; Snyder, Jeremy; Johnston, Rory; Kingsbury, Paul

2011-03-01

255

Transit Dosimetry for Patient Treatment Verification with an Electronic Portal Imaging Device  

NASA Astrophysics Data System (ADS)

The complex and individualized photon fluence patterns constructed during intensity modulated radiation therapy (IMRT) treatment planning must be verified before they are delivered to the patient. There is a compelling argument for additional verification throughout the course of treatment due to the possibility of data corruption, unintentional modification of the plan parameters, changes in patient anatomy, errors in patient alignment, and even mistakes in identifying the correct patient for treatment. Amorphous silicon (aSi) Electronic Portal Imaging Devices (EPIDs) can be utilized for IMRT verification. The goal of this thesis is to implement EPID transit dosimetry, measurement of the dose at a plane behind the patient during their treatment, within the clinical process. In order to achieve this goal, a number of the EPID's dosimetric shortcomings were studied and subsequently resolved. Portal dose images (PDIs) acquired with an aSi EPID suffer from artifacts related to radiation backscattered asymmetrically from the EPID support structure. This backscatter signal varies as a function of field size (FS) and location on the EPID. Its presence can affect pixel values in the measured PDI by up to 3.6%. Two methods to correct for this artifact are offered: discrete FS specific correction matrices and a single generalized equation. The dosimetric comparison between the measured and predicted through-air dose images for 49 IMRT treatment fields was significantly improved (p << .001) after the application of these FS specific backscatter corrections. The formulation of a transit dosimetry algorithm followed the establishment of the backscatter correction and a confirmation of the EPID's positional stability with linac gantry rotation. A detailed characterization of the attenuation, scatter, and EPID response behind an object in the beam's path is necessary to predict transit PDIs. In order to validate the algorithm's performance, 49 IMRT fields were delivered to a number of homogeneous and heterogeneous slab phantoms. A total of 33 IMRT fields were delivered to an anthropomorphic phantom. On average, 98.1% of the pixels in the dosimetric comparison between the measured and predicted transit dose images passed a 3%/3mm gamma analysis. Further validation of the transit dosimetry algorithm was performed on nine human subjects under an institutional review board (IRB) approved protocol. The algorithm was shown to be feasible for patient treatment verification. Comparison between measured and predicted transit dose images resulted in an average of 89.1% of pixels passing a 5%/3mm gamma analysis. A case study illustrated the important role that EPID transit dosimetry can play in indicating when a treatment delivery is inconsistent with the original plan. The impact of transit dosimetry on the clinical workflow for these nine patients was analyzed to identify improvements that could be made to the procedure in order to ease widespread clinical implementation. EPID transit dosimetry is a worthwhile treatment verification technique that strikes a balance between effectiveness and efficiency. This work, which focused on the removal of backscattered radiation artifacts, verification of the EPID's stability with gantry rotation, and the formulation and validation of a transit dosimetry algorithm, has improved the EPID's dosimetric performance. Future research aimed at online transit verification would maximize the benefit of transit dosimetry and greatly improve patient safety.

Berry, Sean L.

256

Study and design of beam expander with wide aperture  

NASA Astrophysics Data System (ADS)

In order to improve the capacity of beam collimation for laser beam expander, it is necessary to design a more reasonable and feasible structure of beam expander system. Laser beam expander is used to compress the laser divergence angle, in order to reduce the energy losing in long distance scanning acquisition system. This paper introduces the working principle and design idea of the laser beam expander, the collimating multiplying power focal length and the collimated magnification formula of expander main, secondary mirror. According to the third-order aberration theory, Considering the spherical aberration, sine difference and divergence angle, the reasonable analysis of optical path, ZEMAX optical design software was used to design large-diameter laser beam expander and analysis and optimize, And given the actual design data and results. Display the maximum optical path difference is +/-0.01? of the main light ray and each light ray. To combination the rear- group objective lens of Galileo and Kepler beam expander, a large-diameter(1.475m) laser beam expander was designed with 0.2m in the diameter, 1/2m in the relative caliber. In the objective lens System, a high-order aspherical was used to the aberration of extra-axial point. we can see that the image quality is close to the diffraction limit from the curves of wavefront. In addition to improve image quality effectively, the system has the characteristics of simple structure, less costly and less design difficulty to compare with the other beam expanding system. And make the output beam's divergence angle smaller, energy density higher, and the beam quality has been greatly improved. The results show that the beam expander is fully meet the design requirements, the use effect is good. Design and research of laser beam expanding system not only improves the quality of the laser beam in the laser system, but also enlarge the application field of laser technology in photoelectric system.

Guo, Ming; Jin, Guangyong; Cai, Jixing; Zhang, Wei; Wei, Zhi

2014-12-01

257

A longitudinal evaluation of diffusion kurtosis imaging in patients with mild traumatic brain injury.  

PubMed

Abstract Primary objective: To investigate longitudinal diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) changes in white and grey matter in patients with mild traumatic brain injury (mTBI). Research design: A prospective case-control study. Methods and procedures: DKI data was obtained from 24 patients with mTBI along with cognitive assessments within 10 days, 1 month and 6 months post-injury and compared with age-matched control (n?=?24). Fractional anisotropy (FA), mean diffusivity (MD), radial diffusion (?r), mean kurtosis (MK) and radial kurtosis (Kr) were extracted from the thalamus, internal capsule and corpus callosum. Main outcomes and results: Results demonstrate reduced Kr and MK in the anterior internal capsule in patients with mTBI across the three visits, and reduced MK in the posterior internal capsule during the 10?day time point. Correlations were observed between the change in MK or Kr between 1-6 months and the improvements in cognition between the 1 and 6 month visits in the thalamus, internal capsule and corpus callosum. Conclusions: These data demonstrate that DKI may be sensitive in tracking pathophysiological changes associated with mTBI and may provide additional information to conventional DTI parameters in evaluating longitudinal changes following TBI. PMID:25259786

Stokum, Jesse A; Sours, Chandler; Zhuo, Jiachen; Kane, Robert; Shanmuganathan, Kathirkamanthan; Gullapalli, Rao P

2015-01-01

258

Malignant transformation in monostotic fibrous dysplasia: clinical features, imaging features, outcomes in 10 patients, and review.  

PubMed

Malignant transformation in fibrous dysplasia (FD) is uncommon. The purpose of this study was to investigate clinical and imaging features, and outcomes of malignant transformation in monostotic FD.Data for 10 pathologically confirmed malignant transformations in monostotic FD from January 2005 to December 2013 were retrospectively reviewed. Patient data were recorded, and radiographs (n?=?10), computed tomography (CT) (n?=?5), magnetic resonance (MR) (n?=?4), and bone scintigrams (n?=?10) were evaluated for lesion location, margin, cortical destruction, marrow involvement, periosteal reaction, and soft tissue mass by 2 musculoskeletal radiologists with agreement by consensus. Clinical features, management, and prognosis were also analyzed for each of the 10 cases.There were 8 male and 2 female patients (mean age 46.5?±?15.9 years). The affected sites were the femur (n?=?4), humerus (n?=?2), tibia (n?=?3), and ilium (n?=?1). Five cases had received previous surgery and 5 cases had no history of surgery. No patients had been given prior irradiation treatment. For the 5 cases with surgery, radiographs and CT showed purely osteolytic lesions with poor margination in the curettage area (n?=?5), cortical destruction (n?=?5), obvious soft tissue mass (n?=?1), and mineralization (n?=?2). For the 5 cases without surgery, radiographs and CT identified poorly marginated, osteolytic lesions within or near the area with "ground-glass" opacity (n?=?4), cortical erosion (n?=?4), and mineralization (n?=?2). Magnetic resonance imaging (MRI) also identified lesions with heterogeneous signal intensity and pronounced enhancement. Bone scintigraphy revealed eccentric increased uptake of radionuclide in monostotic lesion (n?=?10). Pathology reports revealed osteosarcoma (n?=?7), fibrosarcoma (n?=?2), and malignant fibrous histiocytoma (MFH) (n?=?1). At the end of the study, 1 patient died from tumors, 1 patient was alive with lung metastasis, 1 patient experienced recurrence, and 7 patients were alive without recurrence.Patients with FD and a history of surgery should be followed up, for the osteolytic lesions in the operative areas strongly indicate the malignant transformation. The radiographic feature of FD-related malignancies is poorly marginated, mineralized, and osteolytic lesions with cortical destruction. Further investigations are needed to explore the pathogenesis of malignancies in FD and to establish optimal therapeutic strategies. PMID:25621678

Qu, Nan; Yao, Weiwu; Cui, Xiaojiang; Zhang, Huizhen

2015-01-01

259

Advanced expander test bed engine  

NASA Technical Reports Server (NTRS)

The Advanced Expander Test Bed (AETB) is a key element in NASA's Space Chemical Engine Technology Program for development and demonstration of expander cycle oxygen/hydrogen engine and advanced component technologies applicable to space engines as well as launch vehicle upper stage engines. The AETB will be used to validate the high pressure expander cycle concept, study system interactions, and conduct studies of advanced mission focused components and new health monitoring techniques in an engine system environment. The split expander cycle AETB will operate at combustion chamber pressures up to 1200 psia with propellant flow rates equivalent to 20,000 lbf vacuum thrust.

Mitchell, J. P.

1992-01-01

260

SUMMER 2013 CENTER EXPANDS  

E-print Network

sleep onset and sleep maintenance insomnia are common in patients with PD and are likely multi), may contribute to insomnia in PD. Motor fluctuations related to wearing-off of dopaminergic therapy be necessary. Other causes of insomnia not specific to the PD population include psychophysiologic insomnia (in

Bushman, Frederic

261

Practice Briefs: Impacting Practice through Evidence. Patients who injure their foot or ankle should be referred for imaging if they  

E-print Network

Practice Briefs: Impacting Practice through Evidence. Patients who injure their foot or ankle (indicated in black) When does an individual who has sustained an acute ankle or foot injury need imaging? Rationale Imaging of those with acute foot and ankle pain results in many costly radiographs that reveal

Guenther, Frank

262

A method to obtain the same levels of CT image noise for patients of various sizes, to minimize radiation dose  

Microsoft Academic Search

The aim of this study was to develop a method of obtaining the same levels of CT image noise for patients of various sizes to minimize radiation dose. Two CT systems were evaluated regarding noise characteristics using phantoms and dosimetric measurements. Both CT systems performed well at dose levels used in normal clinical imaging, but only one was found to

G STARCK; LL ONN; E FORSSELL; L SJOSTROM; M ALPSTEN

263

Central Nervous System PET-CT Imaging Reveals Regional Impairments in Pediatric Patients with Wolfram Syndrome  

PubMed Central

Wolfram syndrome (WFS) is inherited as an autosomal recessive disease with main clinical features of diabetes mellitus, optic atrophy, diabetes insipidus and deafness. However, various neurological defects may also be detected. The aim of this study was to evaluate aspects of brain structure and function using PET-CT (positron emission tomography and computed tomography) and MRI (magnetic resonance imaging) in pediatric patients with WFS. Regional changes in brain glucose metabolism were measured using standardized uptake values (SUVs) based on images of (18F) fluorodeoxyglucose (FDG) uptake in 7 WFS patients aged 10.1–16.0 years (mean 12.9±2.4) and in 20 healthy children aged 3–17.9 years (mean 12.8±4.1). In all patients the diagnosis of WFS was confirmed by DNA sequencing of the WFS1 gene. Hierarchical clustering showed remarkable similarities of glucose uptake patterns among WFS patients and their differences from the control group. SUV data were subsequently standardized for age groups <13 years old and>13 years old to account for developmental differences. Reduced SUVs in WFS patients as compared to the control group for the bilateral brain regions such as occipital lobe (?1.24±1.20 vs. ?0.13±1.05; p?=?0.028) and cerebellum (?1.11±0.69 vs. ?0.204±1.00; p?=?0.036) were observed and the same tendency for cingulate (?1.13±1.05 vs. ?0.15±1.12; p?=?0.056), temporal lobe (?1.10±0.98 vs. ?0.15±1.10; p?=?0.057), parietal lobe (?1.06±1.20 vs. ?0.08±1.08; p?=?0.058), central region (?1.01±1.04 vs. ?0.09±1.06; p?=?0.060), basal ganglia (?1.05±0.74 vs. ?0.20±1.07; p?=?0.066) and mesial temporal lobe (?1.06±0.82 vs. ?0.26±1.08; p?=?0.087) was also noticed. After adjusting for multiple hypothesis testing, the differences in glucose uptake were non-significant. For the first time, regional differences in brain glucose metabolism among patients with WFS were shown using PET-CT imaging. PMID:25542043

Fendler, Wojciech; Borowiec, Maciej; Antosik, Karolina; Gnys, Piotr; Baranska, Dobromila; Mlynarski, Wojciech

2014-01-01

264

Relationship of pre-surgery metabolic and physiological MR imaging parameters to survival for patients with untreated GBM  

Microsoft Academic Search

Glioblastoma Multiforme (GBM) are heterogeneous lesions, both in terms of their appearance on anatomic images and their response\\u000a to therapy. The goal of this study was to evaluate the prognostic value of parameters derived from physiological and metabolic\\u000a images of these lesions. Fifty-six patients with GBM were scanned immediately before surgical resection using conventional\\u000a anatomical MR imaging and, where possible,

Forrest W. Crawford; Inas S. Khayal; Colleen McGue; Suja Saraswathy; Andrea Pirzkall; Soonmee Cha; Kathleen R. Lamborn; Susan M. Chang; Mitchel S. Berger; Sarah J. Nelson

2009-01-01

265

Multi-observation PET image analysis for patient follow-up quantitation and therapy assessment  

PubMed Central

In Positron Emission Tomography (PET) imaging, an early therapeutic response is usually characterized by variations of semi-quantitative parameters restricted to maximum SUV measured in PET scans during the treatment. Such measurements do not reflect overall tumour volume and radiotracer uptake variations. The proposed approach is based on multi-observation image analysis for merging several PET acquisitions to assess tumour metabolic volume and uptake variations. The fusion algorithm is based on iterative estimation using stochastic expectation maximization (SEM) algorithm. The proposed method was applied to simulated and clinical follow-up PET images. We compared the multi-observation fusion performance to threshold-based methods, proposed for the assessment of the therapeutic response based on functional volumes. On simulated datasets, the adaptive threshold applied independently on both images led to higher errors than the ASEM fusion and on the clinical datasets, it failed to provide coherent measurements for four patients out of seven due to aberrant delineations. The ASEM method demonstrated improved and more robust estimation of the evaluation leading to more pertinent measurements. Future work will consist in extending the methodology and applying it to clinical multi-tracers datasets in order to evaluate its potential impact on the biological tumour volume definition for radiotherapy applications. PMID:21846937

David, Simon; Visvikis, Dimitris; Roux, Christian; Hatt, Mathieu

2011-01-01

266

The Artful Universe Expanded  

NASA Astrophysics Data System (ADS)

Our love of art, writes John Barrow, is the end product of millions of years of evolution. How we react to a beautiful painting or symphony draws upon instincts laid down long before humans existed. Now, in this enhanced edition of the highly popular The Artful Universe , Barrow further explores the close ties between our aesthetic appreciation and the basic nature of the Universe. Barrow argues that the laws of the Universe have imprinted themselves upon our thoughts and actions in subtle and unexpected ways. Why do we like certain types of art or music? What games and puzzles do we find challenging? Why do so many myths and legends have common elements? In this eclectic and entertaining survey, Barrow answers these questions and more as he explains how the landscape of the Universe has influenced the development of philosophy and mythology, and how millions of years of evolutionary history have fashioned our attraction to certain patterns of sound and color. Barrow casts the story of human creativity and thought in a fascinating light, considering such diverse topics as our instinct for language, the origins and uses of color in nature, why we divide time into intervals as we do, the sources of our appreciation of landscape painting, and whether computer-generated fractal art is really art. Drawing on a wide variety of examples, from the theological questions raised by St. Augustine and C.S. Lewis to the relationship between the pure math of Pythagoras and the music of the Beatles, The Artful Universe Expanded covers new ground and enters a wide-ranging debate about the meaning and significance of the links between art and science.

Barrow, John D.

2005-07-01

267

Correction of congenital microtia using the tissue expander.  

PubMed

We attempted auricular reconstruction using Radovan-type inflatable silicone expanders in six children and one adult, with the complete hypoplastic, the conchal remnant, and constricted type of microtia. Ear frameworks, including the helix, anthelix, concha, and tragus, were prepared using autologous rib cartilage. Based on the surface area of the normal adult auricle, the silicone expander was tentatively shaped and sized into a rotated semiellipse and expanded with 70 cc saline. Auricular reconstruction on the framework was completed at the time of insertion in four of the seven patients, requiring no elevation of the ear. The reconstructed auricle was satisfactory in both color and texture and had nearly normal sensation. Mild complications were noted in three of the seven patients. However, no resorption of the inserted rib cartilage has been observed 14 months to 2 years and 5 months after the operation. Slight shrinkage of the expanded skin was noted in each patient. PMID:2813583

Hata, Y; Hosokawa, K; Yano, K; Matsuka, K; Ito, O

1989-11-01

268

Comparing the Use of Diagnostic Imaging and Receipt of Carotid Endarterectomy in Elderly Black and White Stroke Patients  

PubMed Central

Background and Purpose Prior studies show that black patients have carotid endarterectomy less frequently than white patients. Diagnostic imaging is necessary to determine whether a patient is a candidate for the operation. We determined whether there were differences in the use of diagnostic carotid imaging and the frequency of carotid endarterectomy between elderly black and white ischemic stroke patients. Materials and Methods Medicare fee-for-service beneficiaries with discharge diagnoses of ischemic stroke (International Classification of Diseases 9th revision: 433, 434, 436) were randomly selected for inclusion in the National Stroke Project 1998-1999, 2000-2001. Receipt of at least one type of carotid imaging study was compared for black and white patients. Binomial logistic regression models were used to evaluate the associations between race and receipt of carotid imaging and carotid endarterectomy with adjustment for demographics, degree of carotid artery stenosis, and other clinical covariates. Findings Among 19,639 stroke patients (1,974 black; 17,655 white), 69.6% received at least one diagnostic carotid imaging test (blacks, 68.4%; whites, 69.7%; p=0.233). After risk-adjustment, blacks were less likely to receive carotid imaging (adjusted OR, 0.87; 95%CI, 0.78-0.97). There was no relationship between race and the receipt of carotid endarterectomy after adjustment for degree of carotid stenosis and other covariates (adjusted OR, 1.14; 95%CI, 0.66-1.96). Conclusions Black ischemic stroke patients were less likely to receive diagnostic carotid imaging than white patients, although the difference was small, and only significant after risk-adjustment. There was no difference in the proportion having carotid endarterectomy after adjustment for degree of carotid artery stenosis and other clinical factors. PMID:21411337

Martin, Kimberly D.; Naert, Lisa; Goldstein, Larry B.; Kasl, Stanislav; Molinaro, Annette M.; Lichtman, Judith H.

2011-01-01

269

False-positive imaging of In-111 labeled monoclonal antibody conjugate CYT-103 in a patient with metastatic colorectal carcinoma.  

PubMed

In-111 satumomab whole-body imaging is used in the evaluation of patients with colorectal carcinoma. The authors report a case of false-positive In-111 localization in a nonfunctional adrenal adenoma in a patient with metastatic colon carcinoma. PMID:8565379

Bhatia, M; Baron, P L; Alderman, D F; Gordon, L

1995-11-01

270

NOTE Thyroid volume measurement in external beam radiotherapy patients using CT imaging: correlation with clinical and anthropometric characteristics  

Microsoft Academic Search

The aim of this study is to define criteria for accurate representation of the thyroid in human models used to represent external beam radiotherapy (EBRT) patients and evaluate the relationship between the volume of this organ and clinical and anthropometric characteristics. From CT images, we segmented the thyroid gland and calculated its volume for a population of 188 EBRT patients

C. Veres; J. P. Garsi; C. Rubino; F. Pouzoulet; F. Bidault; J. Chavaudra; A. Bridier; M. Ricard; I. Ferreira; D. Lefkopoulos; F. de Vathaire; I. Diallo

2010-01-01

271

Application of flat panel digital imaging for improvement of ocular melanoma patient set-up in proton beam therapy  

Microsoft Academic Search

In order to reduce the dose to surrounding critical tissues and also minimize the probability of recurrence of the tumor the placement of radiation fields relative to patient anatomy is very essential in proton beam therapy of ocular tumors. To achieve this objective, patient setup and field placement have been verified before treatment by analyzing the portal images obtained with

Inder K. Daftari; Timothy Essert; Theodore L. Phillips

2009-01-01

272

Clinical Usefulness of Novel Serum and Imaging Biomarkers in Risk Stratification of Patients with Stable Angina  

PubMed Central

Inflammatory mediators appear to be the most intriguing yet confusing subject, regarding the management of patients with acute coronary syndromes (ACS). The current inflammatory concept of atherosclerotic coronary artery disease (CAD) led many investigators to concentrate on systemic markers of inflammation, as well as imaging techniques, which may be helpful in risk stratification and prognosis assessment for cardiovascular events. In this review, we try to depict many of the recently studied markers regarding stable angina (SA), their clinical usefulness, and possible future applications in the field. PMID:25045198

Ikonomidis, Ignatios; Tsantes, Argirios

2014-01-01

273

The spectrum of Castleman's disease: mimics, radiologic pathologic correlation and role of imaging in patient management.  

PubMed

Castleman's disease (CD) is a rare benign lymphoid disorder with variable clinical course. The two principal histologic subtypes of CD are hyaline-vascular and plasma cell variants and the major clinicoradiological entities are unicentric and multicentric CD. Management of CD is tailored to clinicoradiologic subtype. In this review, we describe the CT, MR and PET/CT findings in Castleman's disease which can help suggest a diagnosis of CD as well as emphasize role of imaging in management of patients with CD. PMID:20643523

Madan, Rachna; Chen, Jey-Hsin; Trotman-Dickenson, Beatrice; Jacobson, Francine; Hunsaker, Andetta

2012-01-01

274

Automated Patient Identification and Localization Error Detection Using 2-Dimensional to 3-Dimensional Registration of Kilovoltage X-Ray Setup Images  

SciTech Connect

Purpose: To determine whether kilovoltage x-ray projection radiation therapy setup images could be used to perform patient identification and detect gross errors in patient setup using a computer algorithm. Methods and Materials: Three patient cohorts treated using a commercially available image guided radiation therapy (IGRT) system that uses 2-dimensional to 3-dimensional (2D-3D) image registration were retrospectively analyzed: a group of 100 cranial radiation therapy patients, a group of 100 prostate cancer patients, and a group of 83 patients treated for spinal lesions. The setup images were acquired using fixed in-room kilovoltage imaging systems. In the prostate and cranial patient groups, localizations using image registration were performed between computed tomography (CT) simulation images from radiation therapy planning and setup x-ray images corresponding both to the same patient and to different patients. For the spinal patients, localizations were performed to the correct vertebral body, and to an adjacent vertebral body, using planning CTs and setup x-ray images from the same patient. An image similarity measure used by the IGRT system image registration algorithm was extracted from the IGRT system log files and evaluated as a discriminant for error detection. Results: A threshold value of the similarity measure could be chosen to separate correct and incorrect patient matches and correct and incorrect vertebral body localizations with excellent accuracy for these patient cohorts. A 10-fold cross-validation using linear discriminant analysis yielded misclassification probabilities of 0.000, 0.0045, and 0.014 for the cranial, prostate, and spinal cases, respectively. Conclusions: An automated measure of the image similarity between x-ray setup images and corresponding planning CT images could be used to perform automated patient identification and detection of localization errors in radiation therapy treatments.

Lamb, James M., E-mail: jlamb@mednet.ucla.edu; Agazaryan, Nzhde; Low, Daniel A.

2013-10-01

275

MR imaging assessment of juxta cortical edema in osteoid osteoma in 28 patients.  

PubMed

Osteoid osteoma (OO) is a benign skeletal neoplasm. Twenty-eight patients with proven OO were studied with MRI regarding soft tissue involvement which was diagnosed when high proton-density and T2-weighted signal intensity and low signal intensity on T1-weighted images were found close to bone. Most tumors were located in the femur and tibia; 6 cases diaphyseal, 12 metaphyso-diaphyseal, and 10 epiphyseal. In relation to the cortex, 15 were located centrally or in its outer margin. Soft tissue involvement was found in 15 patients (53.6 %). A statistical relationship was found between soft tissue involvement and the tumor's location with regard to the cortex, being more frequent in peripherally located tumors. Therefore, soft tissue involvement is a frequent finding in peripherally located OO. PMID:9477273

Nogués, P; Martí-Bonmatí, L; Aparisi, F; Saborido, M C; Garci, J; Dosdá, R

1998-01-01

276

Eating disorder symptoms, psychiatric correlates and self-image in normal, overweight and obese eating disorder patients.  

PubMed

The impression from Swedish eating disorder (ED) units is that there has been an increase in the number of overweight or obese patients. There is, however, no research studying whether these patients differ from normal-weight ED patients in other aspects than weight. Differences between normal-weight and overweight or obese ED patients could indicate that these groups of patients need different treatment approaches. The aim of this study was to investigate possible differences between normal-weight and overweight or obese ED patients in psychiatric and psychological pre-treatment variables. The study was based on data from a Swedish quality assurance system for ED care. In total, data from 3,798 adult patients with body mass index ? 18.5 were used. The sample included all normal-weight ED diagnoses. Significant differences between normal-weight, overweight and obese patients were found for five of eight self-image variables, for all eating disorder examination questionnaire subscales and for most key diagnostic symptoms. However, effect sizes were mostly small or very small. Overweight or obese patients did not display greater levels of psychiatric psychopathology than normal-weight patients. They did, however, show a tendency towards more negative self-image and more severe ED symptoms than normal-weight patients. Overweight and obesity in ED patients are thus not only associated with physical health problems, but also with mental health issues. Further studies are required to investigate the clinical relevance of these findings. PMID:24639071

Lapidoth, Joakim de Man; von Hausswolff-Juhlin, Yvonne

2014-06-01

277

Natural Gas Expanders-Compressors  

Microsoft Academic Search

Natural gas expanders-compressors serve a variety of natural gas plants, ranging from primary treatment at the well (installations for comprehensive treatment of natural gas) to liquefaction for separation, storage, and transport. Natural gas expanders-compressors take on particular importance for wells with throttling cold. The growing demand for this equipment has been satisfied by imports until recently. The most popular was

V. M. Kulakov; V. V. Kulakov; A. V. Kulakov

2002-01-01

278

Short paths in expander graphs  

SciTech Connect

Graph expansion has proved to be a powerful general tool for analyzing the behavior of routing algorithms and the interconnection networks on which they run. We develop new routing algorithms and structural results for bounded-degree expander graphs. Our results are unified by the fact that they are all based upon, and extend, a body of work asserting that expanders are rich in short, disjoint paths. In particular, our work has consequences for the disjoint paths problem, multicommodify flow, and graph minor containment. We show: (i) A greedy algorithm for approximating the maximum disjoint paths problem achieves a polylogarithmic approximation ratio in bounded-degree expanders. Although our algorithm is both deterministic and on-line, its performance guarantee is an improvement over previous bounds in expanders. (ii) For a multicommodily flow problem with arbitrary demands on a bounded-degree expander, there is a (1 + {epsilon})-optimal solution using only flow paths of polylogarithmic length. It follows that the multicommodity flow algorithm of Awerbuch and Leighton runs in nearly linear time per commodity in expanders. Our analysis is based on establishing the following: given edge weights on an expander G, one can increase some of the weights very slightly so the resulting shortest-path metric is smooth - the min-weight path between any pair of nodes uses a polylogarithmic number of edges. (iii) Every bounded-degree expander on n nodes contains every graph with O(n/log{sup O(1)} n) nodes and edges as a minor.

Kleinberg, J. [MIT, Cambridge, MA (United States); Rubinfeld, R. [Cornell Univ., Ithaca, NY (United States)

1996-12-31

279

11C-Acetate PET Imaging in Patients with Multiple Sclerosis  

PubMed Central

Background Activation of glial cells is a cardinal feature in multiple sclerosis (MS) pathology, and acetate has been reported to be selectively uptaken by astrocytes in the CNS. The aim of this study was to investigate the efficacy of PET with 11C-acetate for MS diagnosis. Materials and Methods Six patients with relapsing-remitting MS and 6 healthy volunteers (HV) were enrolled. The 11C-acetate brain uptake on PET was measured in patients with MS and HV. Volume-of-interest analysis of cerebral gray and white matter based on the segmentation technique for co-registered MRI and voxel-based statistical parametric analysis were performed. Correlation between 11C-acetate uptake and the lesion number in T1- and T2- weighted MR images were also assessed. Results The standardized uptake value (SUV) of 11C-acetate was increased in both white and gray matter in MS patients compared to HV. Voxel-based statistical analysis revealed a significantly increased SUV relative to that in the bilateral thalami (SUVt) in a broad area of white matter, particularly in the subcortical white matter of MS patients. The numbers of T2 lesions and T1 black holes were significantly correlated with SUV of 11C-acetate in white and gray matter. Conclusions The 11C-acetate uptake significantly increased in MS patients and correlated to the number of MRI lesions. These preliminary data suggest that 11C-acetate PET can be a useful clinical examination for MS patients. PMID:25369426

Shimosegawa, Eku; Okuno, Tatsusada; Koda, Toru; Sugimoto, Tomoyuki; Mochizuki, Hideki; Hatazawa, Jun; Nakatsuji, Yuji

2014-01-01

280

Reduced subcortical brain volumes in nonpsychotic siblings of schizophrenic patients: a pilot magnetic resonance imaging study.  

PubMed

Substantial evidence suggests that nonpsychotic relatives of schizophrenia patients manifest subtle abnormalities in communication, eye movements, event-related potentials, and neuropsychological processes of attention, reasoning, and memory. We sought to determine whether adult relatives without psychosis or schizophrenia spectrum diagnoses might also have structural brain abnormalities, particularly in subcortical regions found to be impaired in patients with schizophrenia itself. Subjects were six sisters of schizophrenic patients and eleven normal female controls. Sixty contiguous 3 mm coronal, T1-weighted 3D magnetic resonance images (MRI) of the entire brain were acquired on a 1.5 Tesla magnet. Cortical and subcortical gray and white matter was segmented using a semiautomated intensity contour mapping algorithm. Volumes were adjusted for total brain volumes. Adjusted gray matter subcortical volumes were significantly smaller in relatives than in controls in total hippocampus, right amygdala, right putamen, left thalamus, and brainstem. Relatives had significantly enlarged left and total inferior lateral ventricles. These results, though preliminary, suggest that some never-psychotic relatives of schizophrenic patients have abnormal brain structure. If replicated in a larger sample including both sexes, these results would suggest that the genetic liability to schizophrenia is also expressed as structural brain abnormalities. PMID:9342202

Seidman, L J; Faraone, S V; Goldstein, J M; Goodman, J M; Kremen, W S; Matsuda, G; Hoge, E A; Kennedy, D; Makris, N; Caviness, V S; Tsuang, M T

1997-09-19

281

Diffusion Tensor Imaging Studies on Chinese Patients with Social Anxiety Disorder  

PubMed Central

The aim of this study was to explore white-matter disruption in social anxiety disorder (SAD) patients by using diffusion tensor imaging (DTI) and to investigate the relationship between cerebral abnormalities and the severity of the symptoms. Eighteen SAD patients and age- and gender-matched healthy controls were recruited. DTI scans were performed to measure fractional anisotropy (FA) and apparent diffusion coefficient (ADC) for each subject. We used voxel-based analysis to determine the differences of FA and ADC values between the two groups with two-sample t-tests. The SAD patient showed significantly decreased FA values in the white matter of the left insula, left inferior frontal gyrus, left middle temporal gyrus, and left inferior parietal gyrus and increased ADC values in the left insula, bilateral inferior frontal gyrus, bilateral middle temporal gyrus, and left inferior parietal gyrus. In SAD patients, we observed a significant negative correlation between FA values in the left insula and the total LSAS scores and a positive correlation between the ADC values in the left inferior frontal gyrus and the total LSAS scores. Above results suggested that white-matter microstructural changes might contribute to the neuropathology of SAD. PMID:24724105

Qiu, Changjian; Zhu, Chunyan; Zhang, Jingna; Nie, Xiaojing; Feng, Yuan; Meng, Yajing; Wu, Ruizhi; Huang, Xiaoqi; Zhang, Wei; Gong, Qiyong

2014-01-01

282

Immune complex processing in patients with systemic lupus erythematosus. In vivo imaging and clearance studies.  

PubMed Central

Abnormal processing of immune complexes (IC) may be important in the pathogenesis of systemic lupus erythematosus (SLE). The clearance of large soluble IC (comprising hepatitis B surface antigen (HBsAg)/anti-HBsAg) radiolabeled with 123I was examined in 12 normal subjects and 10 patients with SLE. IC localization was analyzed by static and dynamic gamma-scintigraphy. Initial IC clearance from blood was more rapid in patients (median t1/2 = 2.15 min) than normals (median t1/2 = 5.15 min) due to more rapid uptake in the liver. However, in the SLE group, up to 12% of complexes were released from the liver after 30-50 min. Splenic uptake of immune complexes was reduced in the patients and there was reduced ability to retain IC in this organ. Plasma complement levels and erythrocyte complement receptor type 1 numbers were reduced in the patients, resulting in defective opsonization of IC and reduced red cell binding in vivo. These observations support the hypothesis that IC handling is abnormal in SLE. Images PMID:1430231

Davies, K A; Peters, A M; Beynon, H L; Walport, M J

1992-01-01

283

The Role of Imaging in Patient Selection, Preoperative Planning, and Postoperative Monitoring in Human Upper Extremity Allotransplantation  

PubMed Central

Objective. To describe the role of imaging in vascular composite allotransplantation based on one institution's experience with upper extremity allotransplant patients. Methods. The institutional review board approved this review of HIPAA-compliant patient data without the need for individual consent. A retrospective review was performed of imaging from 2008 to 2011 on individuals undergoing upper extremity transplantation. This demonstrated that, of the 19 patients initially considered, 5 patients with a mean age of 37 underwent transplantation. Reports were correlated clinically to delineate which preoperative factors lead to patient selection versus disqualification and what concerns dictated postoperative imaging. Findings were subdivided into musculoskeletal and vascular imaging criterion. Results. Within the screening phase, musculoskeletal exclusion criterion included severe shoulder arthropathy, poor native bone integrity, and marked muscular atrophy. Vascular exclusion criterion included loss of sufficient arterial or venous supply and significant distortion of the native vascular architecture. Postoperative imaging was used to document healing and hardware integrity. Postsurgical angiography and ultrasound were used to monitor for endothelial proliferation or thrombosis as signs of rejection and vascular complication. Conclusion. Multimodality imaging is an integral component of vascular composite allotransplantation surgical planning and surveillance to maximize returning form and functionality while minimizing possible complications. PMID:24800056

Roth, Eira S.; Buck, David G.; Gorantla, Vijay S.; Losee, Joseph E.; Foust, Daniel E.; Britton, Cynthia A.

2014-01-01

284

Visualization of Coronary Wall Atherosclerosis in Asymptomatic Subjects and Patients with Coronary Artery Disease Using Magnetic Resonance Imaging  

Microsoft Academic Search

BackgroundMagnetic resonance imaging (MRI) is sensitive to early atherosclerotic changes such as positive remodeling in patients with coronary artery disease (CAD). We assessed prevalence, quality, and extent of coronary atherosclerosis in a group of healthy subjects compared to patients with confirmed CAD.MethodologyTwenty-two patients with confirmed CAD (15M, 7F, mean age 60.4±10.4 years) and 26 healthy subjects without history of CAD

Suzanne C. Gerretsen; M. Eline Kooi; Alfons G. Kessels; Simon Schalla; Marcus Katoh; Rob J. van der Geest; Warren J. Manning; Johannes Waltenberger; Jos M. A. van Engelshoven; Rene M. Botnar; Tim Leiner

2010-01-01

285

Can Dynamic MR Imaging Predict Response in Patients with Rectal Cancer Undergoing Cetuximab-Based Neoadjuvant Chemoradiation?  

Microsoft Academic Search

SummaryBackground: The aim of this study was to evaluate therapy response in patients undergoing cetuximab-CapIri-based chemoradiation for rectal cancer using dynamic magnetic resonance imaging (dMRI). Patients and Methods: The volumetric degree of tumor regression and contrast media perfusion were compared to the results of the histopathologic ypTN staging. 33 patients were examined using a 1.5-T scanner with repetitive 2D FLASH

Dietmar J. Dinter; Karoline Horisberger; Christian Zechmann; Frederik Wenz; Joachim Brade; Frank Willeke; K. Wolfgang Neff; Stefan O. Schoenberg; Ralf-Dieter Hofheinz

2009-01-01

286

Magnetic resonance imaging guided corticosteroid injection of sacroiliac joints in patients with spondylarthropathy. Are multiple injections more beneficial?  

Microsoft Academic Search

Efficacy of a second magnetic resonance (MR) imaging guided corticosteroid injection of inflamed sacroiliac joints (SIJ) in\\u000a patients with spondylarthropathy. Thirty-one patients received 50 injections in an outpatient basis. Fifteen of 31 patients\\u000a who relapsed or were non-responders received a second injection. All had MR guided injection of 40 mg triamcinolone acetonide\\u000a into SIJ using an open 0.2 Tesla unit. Twenty of

I. Günaydin; P. L. Pereira; J. Fritz; C. König; I. Kötter

2006-01-01

287

The Role of the Nurse in the Rehabilitation of Patients with Radical Changes in Body Image Due to Burn Injuries  

PubMed Central

Summary Burn injuries are among the most serious causes of radical changes in body image. The subject of body image and self-image is essential in rehabilitation, and the nurse must be aware of the issues related to these concepts and take them seriously into account in drafting out the nursing programme. This paper defines certain key words related to body image and discusses the social context of body image. Burn injuries are considered in relation to the way each of these affects the patient's body image. The aim of nursing is defined and the nurse's role in cases of severe changes in body image due to burn injuries is discussed. PMID:21990985

Aacovou, I.

2005-01-01

288

Cardiac assessment of limb-girdle muscular dystrophy 2I patients: an echography, Holter ECG and magnetic resonance imaging study.  

PubMed

Mutations in the FKRP gene may be associated with cardiac involvement. The aim of our study was to assess myocardial involvement in patients with LGMD2I, using physical examination, echocardiography, resting and 24-h ambulatory electrocardiogram and cardiac magnetic resonance imaging, with particular attention to the detection of myocardial morphologic abnormalities. Patients were compared to matched controls. Twenty-three patients were enrolled (men 10--women 13; 32.3+/-9.5 years). Twenty-two had the C826A gene mutation (homozygous 12, heterozygous 10). Nine patients had severe muscle alterations, 10 had milder muscle involvement and 4 had isolated exertional myoglobinuria. When compared to controls, LGMD2I patients had reduced left ventricular ejection fraction (50.8+/-13.9 versus 66.6+/-3.8%, p<0.0001). Sixty percent of patients had reduced left ventricular ejection fraction, including 8% with severe reduced left ventricular ejection fraction <30%. None had significant arrhythmia. Gene mutation and the severity of the muscle disease were not predictive of cardiac involvement. Cardiac magnetic resonance imaging displayed a high prevalence of myocardial functional abnormalities, fatty replacement and fibrosis, among the 13 patients investigated. Reduced contractility and cardiac magnetic resonance imaging morphological abnormalities are highly prevalent in LGMD2I patients suggesting that all patients should be referred for cardiac evaluation. PMID:18639457

Wahbi, Karim; Meune, Christophe; Hamouda, El Hadi; Stojkovic, Tania; Laforêt, Pascal; Bécane, Henri Marc; Eymard, Bruno; Duboc, Denis

2008-08-01

289

Diffusion-weighted MR imaging for assessing synovitis of wrist and hand in patients with rheumatoid arthritis: a feasibility study.  

PubMed

The purpose of this study was to investigate the feasibility of diffusion-weighted imaging (DWI) in detecting synovitis of wrist and hand in patients with rheumatoid arthritis (RA) and evaluate its sensitivity, specificity and accuracy as compared to T2-weighted imaging (T2WI) with short tau inversion recovery (STIR) with the reference standard contrast-enhanced magnetic resonance imaging (CE-MRI). Twenty-five patients with RA underwent MR examinations including DWI, T2WI with STIR and CE-MRI. MR images were reviewed for the presence and location of synovitis of wrist and hand. The sensitivity, specificity and accuracy of DWI and T2WI with STIR were calculated respectively and then compared. All patients included in this study completed MR examinations and yielded diagnostic image quality of DWI. For individual joint, there was good to excellent inter-observer agreement (k=0.62-0.83) using DWI images, T2WI with STIR images and CE-MR images, respectively. There was a significance between DWI and T2WI with STIR in analyzing proximal interphalangeal joints II-V, respectively (P<0.05). The k-values for the detection of synovitis indicated excellent overall inter-observer agreements using DWI images (k=0.86), T2WI with STIR images (k=0.85) and CE-MR images (k=0.91), respectively. Overall, DWI demonstrated a sensitivity, specificity and accuracy of 75.6%, 89.3% and 84.6%, respectively, for detection of synovitis, while 43.0%, 95.7% and 77.6% for T2WI with STIR, respectively. DWI showed positive lesions much better and more than T2WI with STIR. Our results indicate that DWI presents a novel non-invasive approach to contrast-free imaging of synovitis. It may play a role as an addition to standard protocols. PMID:24512797

Li, Xubin; Liu, Xia; Du, Xiangke; Ye, Zhaoxiang

2014-05-01

290

Effect of disease and recovery on functional anatomy in brain tumor patients: insights from functional MRI and diffusion tensor imaging  

PubMed Central

Patients with brain tumors provide a unique opportunity to understand functional brain plasticity. Using advanced imaging techniques, such as functional MRI and diffusion tensor imaging, we have gained tremendous knowledge of brain tumor behavior, transformation, infiltration and destruction of nearby structures. Using these advanced techniques as an adjunct with more proven techniques, such as direct cortical stimulation, intraoperative navigation and advanced microsurgical techniques, we now are able to better formulate safer resection trajectories, perform larger resections at reduced risk and better counsel patients and their families about possible complications. Brain mapping in patients with brain tumors and other lesions has shown us that the old idea of fixed function of the adult cerebral cortex is not entirely true. Improving care for patients with brain lesions in the future will depend on better understanding of the functional organization and plasticity of the adult brain. Advanced noninvasive brain imaging will undoubtedly play a role in advancing this understanding. PMID:24660024

Abd-El-Barr, Muhammad M; Saleh, Emam; Huang, Raymond Y; Golby, Alexandra J

2014-01-01

291

Evaluation of exercise electrocardiography and thallium tomographic imaging in detecting asymptomatic coronary artery disease in diabetic patients.  

PubMed Central

Thallium tomographic imaging and exercise electrocardiography were performed on 136 diabetic patients without symptoms of heart disease. Thirty three patients had post-exercise thallium defects and 19 had ST 1 mm greater than or equal to segment depression during exercise electrocardiography. Both tests were positive in 13 patients. Coronary angiography was subsequently performed on 33 patients with either scintigraphic and/or electrocardiographic evidence of myocardial ischaemia. Angiographically significant coronary artery disease (greater than or equal to 50% narrowing of the coronary artery lumen) was detected in 13 patients. Six patients had minimal coronary artery stenosis (less than 50%), and 14 had normal coronary arteries. Six patients refused cardiac catheterisation. In 14 out of 27 patients with post-exercise thallium defects coronary angiography did not show any coronary artery stenoses (positive predictive accuracy 48%). Exercise electrocardiography showed only one false positive result (positive predictive accuracy 94%) but failed to detect coronary artery disease in three patients with a positive scintigraphic result. The accuracy of a positive exercise electrocardiographic test seems to be better than that of a positive thallium tomographic scan for detecting asymptomatic coronary artery disease in diabetic patients. The high number of false positive thallium defects may be the result of technical features inherent in thallium tomography and/or the possible disease of the small intramyocardial arteries in diabetic patients. Images PMID:2310651

Koistinen, M J; Huikuri, H V; Pirttiaho, H; Linnaluoto, M K; Takkunen, J T

1990-01-01

292

Functional MR imaging of the motor cortex in healthy volunteers and patients with brain tumours: qualitative and quantitative results.  

PubMed

The purpose of this study was to compare functional magnetic resonance (MR) imaging of the motor cortex in healthy volunteers and patients with brain tumours. Functional MR imaging was performed in 14 healthy volunteers and 14 patients with tumours in or near the primary motor cortex with groups being matched for age, sex, and handedness. Functional images were acquired during motion of the right and left hand. Time courses of signal intensity within the contralateral, ipsilateral, and supplementary motor cortex as well as z-maps were calculated, their quality being assessed visually. Mean signal increase between activation and rest were evaluated within the contralateral, ipsilateral, and supplementary motor cortex, the activated area in those regions of interest was measured using z-maps. The quality of functional MR experiments was generally lower in patients than in volunteers. The quantitative results showed a trend towards increased ipsilateral activation in volunteers during left hand compared to right hand motion and in patients during motion of the affected compared to the non-affected hand. Considering quantitative and qualitative results, significantly increased ipsilateral activation was found in patients compared to healthy volunteers. In conclusion, functional MR imaging quality was significantly reduced in patient studies compared to healthy volunteers, even if influences of age, sex, and handedness were excluded. Increased ipsilateral activation was found in patients with brain tumours which can be interpreted by an improved connectivity between both hemispheres. PMID:10321113

Fellner, C; Schlaier, J; Fellner, F; Held, P; Blank, M; Schwerdtner, J; Brawanski, A; Kalender, W A

1999-01-01

293

Assessment of allograft function using diffusion-weighted magnetic resonance imaging in kidney transplant patients.  

PubMed

Developing a non-invasive method such as diffusion-weighted magnetic resonance imaging (DWMRI) could be used as a feasible and reproducible modality in the differential diagnosis of allograft dysfunction. We assessed the functional status of the renal allograft by DWMRI and its applicability in assessment of graft dysfunction on all end-stage renal transplant patients who attained normal renal function on the 7 th day post-transplantation. Follow-up imaging of the recipient allograft was performed at the end of 90 and 180 days and in case of graft dysfunction. Kidney biopsies were performed to correlate with the corresponding MRI. The apparent diffusion coefficient (ADC) maps of the cortex and medulla were obtained by studying the DWMRI. The ADC values were significantly lower in the medulla compared with the cortex in normal donor kidneys and normally functioning transplanted kidneys, while they decreased significantly when rejection occurred. The reduction in ADC values occurred both in the cortex and in the medulla, and correlated with the degree of rejection on the kidney biopsies. The ADC values increased significantly during the recovery from rejection. We conclude that DWMRI can be beneficial in the diagnosis and follow-up of transplant patients during acute rejection. PMID:25394428

Kaul, Anupma; Sharma, Raj Kumar; Gupta, Rakesh Kumar; Lal, Hira; Yadav, Abhishek; Bhadhuria, Dharmendra; Prasad, Narayan; Gupta, Amit

2014-01-01

294

Respiration-Correlated Image Guidance Is the Most Important Radiotherapy Motion Management Strategy for Most Lung Cancer Patients  

SciTech Connect

Purpose: The purpose of this study was to quantify the effects of four-dimensional computed tomography (4DCT), 4D image guidance (4D-IG), and beam gating on calculated treatment field margins in a lung cancer patient population. Materials and Methods: Images were acquired from 46 lung cancer patients participating in four separate protocols at three institutions in Europe and the United States. Seven patients were imaged using fluoroscopy, and 39 patients were imaged using 4DCT. The magnitude of respiratory tumor motion was measured. The required treatment field margins were calculated using a statistical recipe (van Herk M, et al. Int J Radiat Oncol Biol Phys 2000;474:1121-1135), with magnitudes of all uncertainties, except respiratory peak-to-peak displacement, the same for all patients, taken from literature. Required margins for respiratory motion management were calculated using the residual respiratory tumor motion for each patient for various motion management strategies. Margin reductions for respiration management were calculated using 4DCT, 4D-IG, and gated beam delivery. Results: The median tumor motion magnitude was 4.4 mm for the 46 patients (range 0-29.3 mm). This value corresponded to required treatment field margins of 13.7 to 36.3 mm (median 14.4 mm). The use of 4DCT, 4D-IG, and beam gating required margins that were reduced by 0 to 13.9 mm (median 0.5 mm), 3 to 5.2 mm (median 5.1 mm), and 0 to 7 mm (median 0.2 mm), respectively, to a total of 8.5 to 12.4 mm (median 8.6 mm). Conclusion: A respiratory management strategy for lung cancer radiotherapy including planning on 4DCT scans and daily image guidance provides a potential reduction of 37% to 47% in treatment field margins. The 4D image guidance strategy was the most effective strategy for >85% of the patients.

Korreman, Stine, E-mail: korreman@ruc.dk [Department of Science, Systems and Models, Roskilde University, Roskilde (Denmark); Department of Radiation Oncology, The Finsen Centre, Rigshospitalet, Copenhagen (Denmark); Niels Bohr Institute, University of Copenhagen, Copenhagen (Denmark); Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison (United States); Persson, Gitte; Nygaard, Ditte [Department of Radiation Oncology, The Finsen Centre, Rigshospitalet, Copenhagen (Denmark); Brink, Carsten [Laboratory of Radiation Physics, Odense University Hospital, Odense (Denmark); Faculty of Health Sciences, University of Southern Denmark, Odense (Denmark); Juhler-Nottrup, Trine [Department of Oncology, Herlev Hospital, Copenhagen (Denmark)

2012-07-15

295

[Cost effectiveness and patient benefit of digital image management systems for radiology].  

PubMed

In many countries today, politicians are faced with the difficulty of having to reduce the overproportional increase in the cost of healthcare. In this context the contribution of medical technology to costs in the total spent are nearly always overestimated and its potential for savings underestimated. Based on international studies, investment and subsequent running costs for large, high-tech systems for diagnosis and therapy will be shown to account for only about 1% of the total cost of healthcare. Impressive examples of the application of computed tomography, magnetic resonance tomography and digital angiography deliver statistics regarding valid patient benefits and efficiency of modern diagnostic imaging systems. Studies about related therapeutic possibilities of angioplasty and extra-corporal lithotripsy demonstrate the overall economic advantages of modern medical technology. Arising from the positive results due to the use of such equipment, the additional cost savings potential to be expected by networking these digital modalities with one another, as well as with other information and communications technology systems, will be analysed. The results will be assessed and compared to experience gained from routine clinical operation of such integrated systems. 72% of the total turnover of the Medical Engineering Group of Siemens AG for diagnostic imaging modalities in 1991/1992 arose from digital imaging modalities, and this percentage is expected to continue to increase. This paper will concentrate on these modern digital methods. PMID:7918710

Grassmann, P; Greinacher, C F; Maly, W

1994-07-01

296

Endovascular Repair of Arterial Iliac Vessel Wall Lesions with a Self-Expandable Nitinol Stent Graft System  

PubMed Central

Objective To assess the therapeutic outcome after endovascular repair of iliac arterial lesions (IALs) using a self-expandable Nitinol stent graft system. Methods Between July 2006 and March 2013, 16 patients (13 males, mean age: 68 years) with a self-expandable Nitinol stent graft. A total of 19 lesions were treated: nine true aneurysms, two anastomotic aneurysms, two dissections, one arteriovenous fistula, two type 1B endoleaks after endovascular aneurysm repair, one pseudoaneurysm, and two perforations after angioplasty. Pre-, intra-, and postinterventional imaging studies and the medical records were analyzed for technical and clinical success and postinterventional complications. Results The primary technical and clinical success rate was 81.3% (13/16 patients) and 75.0% (12/16), respectively. Two patients had technical failure due to persistent type 1A endoleak and another patient due to acute stent graft thrombosis. One patient showed severe stent graft kinking on the first postinterventional day. In two patients, a second intervention was performed. The secondary technical and clinical success rate was 87.5% (14/16) and 93.8% (15/16). The minor complication rate was 6.3% (patient with painful hematoma at the access site). The major complication rate was 6.3% (patient with ipsilateral deep vein thrombosis). During median follow-up of 22.4 months, an infection of the aneurysm sac in one patient and a stent graft thrombosis in another patient were observed. Conclusion Endovascular repair of various IALs with a self-expandable Nitinol stent graft is safe and effective. PMID:25119346

Mensel, Birger; Kühn, Jens-Peter; Hoene, Andreas; Hosten, Norbert; Puls, Ralf

2014-01-01

297

Metabolic imaging of patients with prostate cancer using hyperpolarized [1-¹³C]pyruvate.  

PubMed

This first-in-man imaging study evaluated the safety and feasibility of hyperpolarized [1-¹³C]pyruvate as an agent for noninvasively characterizing alterations in tumor metabolism for patients with prostate cancer. Imaging living systems with hyperpolarized agents can result in more than 10,000-fold enhancement in signal relative to conventional magnetic resonance (MR) imaging. When combined with the rapid acquisition of in vivo ¹³C MR data, it is possible to evaluate the distribution of agents such as [1-¹³C]pyruvate and its metabolic products lactate, alanine, and bicarbonate in a matter of seconds. Preclinical studies in cancer models have detected elevated levels of hyperpolarized [1-¹³C]lactate in tumor, with the ratio of [1-¹³C]lactate/[1-¹³C]pyruvate being increased in high-grade tumors and decreased after successful treatment. Translation of this technology into humans was achieved by modifying the instrument that generates the hyperpolarized agent, constructing specialized radio frequency coils to detect ¹³C nuclei, and developing new pulse sequences to efficiently capture the signal. The study population comprised patients with biopsy-proven prostate cancer, with 31 subjects being injected with hyperpolarized [1-¹³C]pyruvate. The median time to deliver the agent was 66 s, and uptake was observed about 20 s after injection. No dose-limiting toxicities were observed, and the highest dose (0.43 ml/kg of 230 mM agent) gave the best signal-to-noise ratio for hyperpolarized [1-¹³C]pyruvate. The results were extremely promising in not only confirming the safety of the agent but also showing elevated [1-¹³C]lactate/[1-¹³C]pyruvate in regions of biopsy-proven cancer. These findings will be valuable for noninvasive cancer diagnosis and treatment monitoring in future clinical trials. PMID:23946197

Nelson, Sarah J; Kurhanewicz, John; Vigneron, Daniel B; Larson, Peder E Z; Harzstark, Andrea L; Ferrone, Marcus; van Criekinge, Mark; Chang, Jose W; Bok, Robert; Park, Ilwoo; Reed, Galen; Carvajal, Lucas; Small, Eric J; Munster, Pamela; Weinberg, Vivian K; Ardenkjaer-Larsen, Jan Henrik; Chen, Albert P; Hurd, Ralph E; Odegardstuen, Liv-Ingrid; Robb, Fraser J; Tropp, James; Murray, Jonathan A

2013-08-14

298

Metabolic Imaging of Patients with Prostate Cancer Using Hyperpolarized [1-13C]Pyruvate  

PubMed Central

This first-in-man imaging study evaluated the safety and feasibility of hyperpolarized [1-13C]pyruvate as an agent for noninvasively characterizing alterations in tumor metabolism for patients with prostate cancer. Imaging living systems with hyperpolarized agents can result in more than 10,000-fold enhancement in signal relative to conventional magnetic resonance (MR) imaging. When combined with the rapid acquisition of in vivo 13C MR data, it is possible to evaluate the distribution of agents such as [1-13C]pyruvate and its metabolic products lactate, alanine, and bicarbonate in a matter of seconds. Preclinical studies in cancer models have detected elevated levels of hyperpolarized [1-13C]lactate in tumor, with the ratio of [1-13C]lactate/[1-13C]pyruvate being increased in high-grade tumors and decreased after successful treatment. Translation of this technology into humans was achieved by modifying the instrument that generates the hyperpolarized agent, constructing specialized radio frequency coils to detect 13C nuclei, and developing new pulse sequences to efficiently capture the signal. The study population comprised patients with biopsy-proven prostate cancer, with 31 subjects being injected with hyperpolarized [1-13C]pyruvate. The median time to deliver the agent was 66 s, and uptake was observed about 20 s after injection. No dose-limiting toxicities were observed, and the highest dose (0.43 ml/kg of 230 mM agent) gave the best signal-to-noise ratio for hyperpolarized [1-13C]pyruvate. The results were extremely promising in not only confirming the safety of the agent but also showing elevated [1-13C]lactate/[1-13C]pyruvate in regions of biopsy-proven cancer. These findings will be valuable for noninvasive cancer diagnosis and treatment monitoring in future clinical trials. PMID:23946197

Nelson, Sarah J.; Kurhanewicz, John; Vigneron, Daniel B.; Larson, Peder E. Z.; Harzstark, Andrea L.; Ferrone, Marcus; van Criekinge, Mark; Chang, Jose W.; Bok, Robert; Park, Ilwoo; Reed, Galen; Carvajal, Lucas; Small, Eric J.; Munster, Pamela; Weinberg, Vivian K.; Ardenkjaer-Larsen, Jan Henrik; Chen, Albert P.; Hurd, Ralph E.; Odegardstuen, Liv-Ingrid; Robb, Fraser J.; Tropp, James; Murray, Jonathan A.

2014-01-01

299

Ocular findings in patients with alopecia areata: role of ultra-wide-field retinal imaging.  

PubMed

Alopecia areata is understood as an autoimmune disease T cell-mediated mainly involving hair follicles in humans. It is a multifactorial aetiologic disease characterised by non-scarring alopecia and asymptomatic areas, affecting approximately 2 % of dermatology patients. Recent studies suggest that the pathogenesis of AA plays an important role in the association of certain HLA groups, neuroendocrine parameters and immunogenic factors. During 3 months (March to May 2013) at Hospital Clínic de Barcelona, 22 patients with severe alopecia areata underwent ophthalmic examination to determine whether there were ocular findings in the following parameters: Best-corrected visual acuity on decimal Snellen optotype, anterior segment slit-lamp examination and photograph, intraocular pressure measurement and dilated fundoscopy. Ultra-wide-field retinal imaging with or without red-free photograph was carried out with the Optomap 200 Tx (Optos, DunFermline, UK). Forty-four eyes of 22 patients were analysed [15 females (68.2 %)]. The mean age was 38.9 (SD 13.7) and mean time of evolution was 19.9 years (SD 16.3). Alopecia areata clinical patterns were multifocal [n = 10 (45.5 %)], universalis [n = 7 (31.8 %)], totalis [n = 3 (13.6 %)] and focal [n = 2 (9.1 %)]. Best-corrected visual acuity was 1.0 in almost all patients, but only three eyes (6.8 %) had vision of 0.7. Ocular findings were as follows: madarosis [n = 7 partial loss of eyelashes (31.85 %) and n = 4 total loss (18.2 %)], lens changes [n = 4 (18.2 %)], cataract [n = 3 (13.65 %)]. Ultra-wide fundus photography examination showed peripheral drusen [n = 17 eyes (38.6 %)], white-without-pressure changes [n = 8 eyes (18.22 %)] and peripheral retinal degenerations [n = 3 eyes (6.81 %)]. Ocular findings in patients with alopecia areata are reported and discussed by dermatologic and ophthalmic evaluation. PMID:25450413

de Andrade, Francisco Assis; Giavedoni, Priscila; Keller, Johannes; Sainz-de-la-Maza, Maria Tereza; Ferrando, Juan

2014-12-01

300

Analysis of diaphragmatic movement before and after pulmonary rehabilitation using fluoroscopy imaging in patients with COPD  

PubMed Central

Background The diaphragm is the principal inspiratory muscle. The purpose of this study was to assess improvements in diaphragmatic movement before and after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD), using a fluoroscopy-guided chest X-ray. Patients and methods Among 117 patients with COPD receiving pulmonary rehabilitation who underwent the initial fluoroscopy-guided chest X-ray and pulmonary function test, 37 of those patients who underwent both initial and follow-up fluoroscopy and pulmonary function tests were enrolled in this study. After hospital education, participants received pulmonary rehabilitation through regular home-based training for at least 3 months by the same physiatrist. We assessed the changes in diaphragm area with fluoroscopy-guided posteroanterior chest X-rays between pre- and postpulmonary rehabilitation. To minimize radiation hazards for subjects, the exposure time for fluoroscopy to take chest X-rays was limited to less than 5 seconds. Results There were significant improvements (2,022.8±1,548.3 mm2 to 3,010.7±1,495.6 mm2 and 2,382.4±1,475.9 mm2 to 3,315.9±1,883.5 mm2; right side P=0.001 and left side P=0.019, respectively) in diaphragmatic motion area during full inspiration and expiration in both lungs after pulmonary rehabilitation. Pulmonary function tests showed no statistically significant difference between pre- and postpulmonary rehabilitation. Conclusion The study suggests that the strategy to assess diaphragm movement using fluoroscopy is a relatively effective tool for the evaluation of pulmonary rehabilitation in COPD patients in terms of cost and time savings compared with computed tomography or magnetic resonance imaging.

Chun, Eun Mi; Han, Soo Jeong; Modi, Hitesh N

2015-01-01

301

Lesion comparison of multiple sclerosis in hispanic and caucasian patients utilizing an imaging informatics-based eFolder system  

NASA Astrophysics Data System (ADS)

Multiple sclerosis (MS) is a demyelinating disease in the central nervous system. Genetics have been considered as a leading factor in the prevalence and disease course of MS. We have presented an informatics-based eFolder system for integrating patients' clinical data with MR images and lesion quantification results. The completed eFolder system has been designed and developed in aiding to evaluate disease manifestation differences in Hispanic and Caucasian MS patients. MS lesion data, as shown in MRI, can be extracted by the 3-D automatic lesion detection tool in the eFolder, and data storing and mining tools in eFolder is able to extract and compare data from individual patients. The computer-aided detection (CAD) algorithm has been modified and enhanced to include spatial information as detection criteria. For this study, 36 Caucasian MS patients and 36 matched Hispanic patients have been selected. Most recent MR images of the patients are collected, and images are evaluated both by the CAD tool in the eFolder and radiologists. The results are compared between Caucasian and Hispanic patients and statistically evaluated to see if the two populations have significant difference in lesion presentations. The results can be used to evaluate differences in the two groups of patients and to evaluate the new CAD algorithm's performance with radiologists' contours. Significant findings can further evaluate effectiveness of MS eFolder in MS-related research.

Ma, Kevin; Fernandez, James; Amezcua, Lilyana; Lerner, Alex; Shiroishi, Mark; Liu, Brent

2012-02-01

302

Monolithical aspherical beam expanding systems  

NASA Astrophysics Data System (ADS)

Beam expanding is a common task, where Galileo telescopes are preferred. However researches and customers have found limitations when using these systems. A new monolithical solution which is based on the usage of only one aspherical component will be presented. It will be shown how to combine up to five monolithical beam expanding systems and to keep the beam quality at diffraction limitation. Insights will be given how aspherical beam expanding systems will help using larger incoming beams and reducing the overall length of such a system. Additionally an add-on element for divergence and wavelength adaption will be presented.

Fuchs, U.; Matthias, Sabrina

2014-10-01

303

A comparison of dipyridamole-thallium imaging and exercise testing in the prediction of postoperative cardiac complications in patients requiring arterial reconstruction  

Microsoft Academic Search

The individual and combined predictive values of dipyridamole-thallium imaging and exercise testing were compared in a prospective study of 70 patients who had abdominal aortic aneurysms or aortoiliac occlusive disease that required surgical repair. All patients were evaluated clinically by the same cardiologist and had exercise stress testing and dipyridamole-thallium imaging before admission for surgery. Ten patients were excluded from

N. V. McPhail; T. D. Ruddy; J. E. Calvin; R. A. Davies; G. G. Barber

1989-01-01

304

Imagery special issue: intrusive images and memories of earlier adverse events in patients with obsessive compulsive disorder.  

PubMed

Mental imagery is increasingly considered to be an important feature in anxiety disorders. The aim of this study was to investigate the prevalence and characteristics of mental images in obsessive compulsive disorder (OCD) and their possible association with earlier adverse events. A consecutive sample of 37 patients with OCD admitted to a specialist unit was interviewed using a semi-structured interview. Thirty (81%) patients with OCD reported mental images. Most images were either memories of earlier adverse events (n=10 or 34%) or were associated with them (n=13 or 45%). Patients with mental images had more obsessive compulsive symptoms, responsibility beliefs and anxiety than those without. Previous research has shown that patients with OCD and comorbid posttraumatic stress disorder might not benefit as much from standard behavioural treatment as those without. Consequently, additional therapeutic interventions such as imaginal reliving and restructuring of meaning or imagery modification of traumatic memories might be helpful in OCD patients with mental images that are linked to earlier adverse events. PMID:18005933

Speckens, Anne E M; Hackmann, Ann; Ehlers, Anke; Cuthbert, Bea

2007-12-01

305

Seizure source imaging by means of FINE spatio-temporal dipole localization and directed transfer function in partial epilepsy patients  

PubMed Central

Objective To investigate the usage of a high-density EEG recording system and source imaging technique for localizing seizure activity in patients with medically intractable partial epilepsy. Methods High-density, 76-channel scalp EEG signals were recorded in ten patients with partial epilepsy. The patients underwent routine clinical pre-surgical evaluation and all had resective surgery with seizure free outcome. After applying a FINE (first principle vectors) spatial-temporal source localization and DTF (directed transfer function) connectivity analysis approach, ictal sources were imaged. Effects of number of scalp EEG electrodes on the seizure localization were also assessed using 76, 64, 48, 32, and 21 electrodes, respectively. Results Surgical resections were used to assess the source imaging results. Results from the 76-channel EEG in the ten patients showed high correlation with the surgically resected brain regions. The localization of seizure onset zone from 76-channel EEG showed improved source detection accuracy compared to other EEG configurations with fewer electrodes. Conclusions FINE together with DTF was able to localize seizure onset zones of partial epilepsy patients. High-density EEG recording can help achieve improved seizure source imaging. Significance The present results suggest the promise of high-density EEG and electrical source imaging for noninvasively localizing seizure onset zones. PMID:22172768

Lu, Yunfeng; Yang, Lin; Worrell, Gregory; He, Bin

2011-01-01

306

Imaging technique for the complete edentulous patient treated conventionally or with mini implant overdenture  

PubMed Central

Rationale. The imaging methods are more and more used in the clinical process of modern dentistry. Once the implant based treatment alternatives are nowadays seen as being the standard of care in edentulous patients, these techniques must be integrated in the complete denture treatment. Aim. The study presents some evaluation techniques for the edentulous patient treated by conventional dentures or mini dental implants (mini SKY Bredent) overdentures, using the profile teleradiography. These offer data useful for an optimal positioning of the artificial teeth and the mini dental implants, favoring to obtain an esthetic and functional treatment outcome. We proposed also a method to conceive a simple surgical guide that allows the prosthetically driven implants placement. Material and method. Clinical case reports were made, highlighting the importance of cephalometric evaluation on lateral teleradiographs in complete edentulous patients. A clinical case that gradually reports the surgical guide preparation (Bredent silicon radio opaque), in order to place the mini dental implants in the best prosthetic and anatomic conditions, was presented. Conclusions. The profile teleradiograph is a useful tool for the practitioner. It allows establishing the optimal site for implant placement, in a good relation with the overdenture. The conventional denture can be easily and relatively costless transformed in a surgical guide used during implant placement. PMID:23599828

Mele?canu Imre, M; Preoteasa, E; ?âncu, AM; Preoteasa, CT

2013-01-01

307

Acute colonic pseudo-obstruction complicating chemotherapy in paediatric oncohaematological patients: clinical and imaging features  

PubMed Central

Objective Although acute colonic pseudo-obstruction (ACPO) complicating chemotherapy is still a controversial entity, it is one with which radiologists should be familiar. We describe the imaging features of ACPO in children following chemotherapy for treatment of a haematological malignancy. Methods We retrospectively reviewed the imaging features of eight children (age 3–14 years) with chemotherapy-related ACPO, all of whom had undergone plain radiography and CT examinations. The diagnosis of ACPO was based on both clinical features and imaging findings. Results Abnormalities noted on plain radiography included faecal gaseous distension of the transverse colon (4/8), faecal gaseous distension of the ascending colon (3/8), gaseous distended transverse colon (3/8) and gaseous small bowel loops (6/8). As seen on CT scans, findings of faecal fluid distended the ascending and transverse colon (5/8), faecal gas distended the transverse and ascending colon (3/8), and small bowel dilatation (5/8) and pneumatosis intestinalis (2/8) were noted. Seven of the eight patients had colonic dilatation from the caecum to the transverse colon with the transition zone near the splenic flexure. Conclusion In children presenting with abdominal pain and constipation following chemotherapy, imaging features of progressive colonic dilatation seen on radiography and dilatation from the caecum to the transverse colon with the transition zone near the splenic flexure, as noted on CT, are suggestive of ACPO. CT is more successful than plain radiography for evaluating this finding, particularly in colonic segments filled primarily with fluid, but CT should not be necessary for making the diagnosis as plain radiographs and clinical evaluation should be adequate. PMID:21828148

Lee, G E; Lim, G-Y; Lee, J-W; Cho, B

2012-01-01

308

Expanding Disparity Range in an FPGA Stereo System While Keeping Resource Utilization Low  

E-print Network

Expanding Disparity Range in an FPGA Stereo System While Keeping Resource Utilization Low Divyang K adapting a system to deal with larger image sizes or, in the case of stereo disparity estimation, larger to expand the dispar- ity range and input image size of an existing FPGA-based stereo system [8] while

MacLean, W. James

309

Longitudinal HR-pQCT and Image Registration Detects Endocortical Bone Loss in Kidney Transplantation Patients.  

PubMed

Patients with chronic kidney disease (CKD) who undergo kidney transplantation experience bone loss and increased risk of fracture. However, the mechanisms of this bone loss are unclear. Our objective was to use image registration to define the cortex to assess changes in cortical porosity (Ct.Po) in patients undergoing first time kidney transplantation. We obtained serial measurements of parathyroid hormone (PTH) and bone turnover markers and used high-resolution peripheral quantitative computed tomography (HR-pQCT) to scan the distal radius and tibia in 31 patients (21 men, 10 women; age: 51.9?±?13.4) at transplant and after 1 year. Baseline and 1 year images were aligned using a fully automated, intensity-based image registration framework. We compared three methods to define the cortical region of interest (ROI) and quantify the changes: 1) cortical bone was independently defined in baseline and follow-up scans; 2) cortical bone was defined as the common cortical ROI; and 3) the cortical ROI at baseline was carried forward to 1 year follow-up (baseline-indexed). By the independently defined ROI, Ct.Po increased 11.7% at the radius and 9.1% at the tibia, whereas by the common ROI, Ct.Po increased 14.6% at the radius and 9.1% at the tibia. By the baseline-indexed ROI, which provides insight into changes at the endocortical region, Ct.Po increased 63.4% at the radius and 17.6% at the tibia. We found significant relationships between changes in Ct.Po and bone formation and resorption markers at the radius. The strongest associations were found between markers and Ct.Po using the baseline-index method. We conclude that Ct.Po increases throughout the cortex after kidney transplant and this increase is particularly marked at the endocortical surface. These methods may prove useful for all HR-pQCT longitudinal studies, particularly when changes are expected at the endocortical region. © 2014 American Society for Bone and Mineral Research. PMID:25213758

Nishiyama, Kyle K; Pauchard, Yves; Nikkel, Lucas E; Iyer, Sapna; Zhang, Chiyuan; McMahon, Donald J; Cohen, David; Boyd, Steven K; Shane, Elizabeth; Nickolas, Thomas L

2014-09-11

310

Application of flat panel digital imaging for improvement of ocular melanoma patient set-up in proton beam therapy  

NASA Astrophysics Data System (ADS)

In order to reduce the dose to surrounding critical tissues and also minimize the probability of recurrence of the tumor the placement of radiation fields relative to patient anatomy is very essential in proton beam therapy of ocular tumors. To achieve this objective, patient setup and field placement have been verified before treatment by analyzing the portal images obtained with Polaroid film-camera system. The Polaroid films are becoming expensive and obsolete, making new methods of verifying the patient treatment position essential. The objective of this study was to implement an orthogonal flat panel digital imaging (FPDI) system as a tool to image-guided radiation therapy (IGRT) on the UC Davis cyclotron proton beam therapy line and to use the system for patient setup verification. The image quality of the system is sufficient to see an air hole with a diameter of 0.5 mm at a depth of 9 mm, in a 10 cm Lucite phantom. The subject contrast of the FPDI system varied from 16% to 29% by varying the size of the air hole in the phantom from 1 to 5 mm and changing the depth from 9 to 15 mm. The subject contrast for 0.5 mm air hole was 11%. The comparison of the setup variations as measured from Polaroid port films and FPDI was 0.1±0.7 mm in the X-direction, 0.2±0.2 mm in the Y-direction and 0.04±0.1 mm in Z-direction, respectively. The day-to-day positional variations in-patient set-ups were studied for 30 patients using the FPDI system. The patient position set-up on first day of treatment [defined by the X, Y, Z coordinates of the chair and head holder] was registered as the reference image. The comparison of day-to-day patient position with reference image indicated net translation along the three orthogonal axes as 0.3±1.88 mm in right-left direction, -0.3±1.78 in superior-inferior direction and -0.6±2.8 mm in anterior-posterior direction. The image quality of the FPDI system was sufficient to clearly reveal the radio-opaque markers on the digital image. In conclusion a FPDI system can accurately replace the Polaroid system and will facilitate daily portal alignment and true electronic IGRT verification of patient position and tumor location relative to the proton beam.

Daftari, Inder K.; Essert, Timothy; Phillips, Theodore L.

2009-01-01

311

Improvement in toxicity in high risk prostate cancer patients treated with image-guided intensity-modulated radiotherapy compared to 3D conformal radiotherapy without daily image guidance  

PubMed Central

Background Image-guided radiotherapy (IGRT) facilitates the delivery of a very precise radiation dose. In this study we compare the toxicity and biochemical progression-free survival between patients treated with daily image-guided intensity-modulated radiotherapy (IG-IMRT) and 3D conformal radiotherapy (3DCRT) without daily image guidance for high risk prostate cancer (PCa). Methods A total of 503 high risk PCa patients treated with radiotherapy (RT) and endocrine treatment between 2000 and 2010 were retrospectively reviewed. 115 patients were treated with 3DCRT, and 388 patients were treated with IG-IMRT. 3DCRT patients were treated to 76 Gy and without daily image guidance and with 1–2 cm PTV margins. IG-IMRT patients were treated to 78 Gy based on daily image guidance of fiducial markers, and the PTV margins were 5–7 mm. Furthermore, the dose-volume constraints to both the rectum and bladder were changed with the introduction of IG-IMRT. Results The 2-year actuarial likelihood of developing grade?>?= 2 GI toxicity following RT was 57.3% in 3DCRT patients and 5.8% in IG-IMRT patients (p??= 2 GI toxicity compared to IG-IMRT (p?image guidance and margin reduction. PMID:24495815

2014-01-01

312

Serial analysis of imaging parameters in patients with newly diagnosed glioblastoma multiforme  

PubMed Central

The objective of this study was to test the predictive value of serial MRI data in relation to clinical outcome for patients with glioblastoma multiforme (GBM). Sixty-four patients with newly diagnosed GBM underwent conventional MRI and diffusion-weighted and perfusion-weighted imaging postsurgery and prior to radiation/chemotherapy (pre-RT), immediately after RT (post-RT), and every 1–2 months thereafter until tumor progression, up to a maximum of 1 year. Tumor volumes and perfusion and diffusion parameters were calculated and subject to time-independent and time-dependent Cox proportional hazards models that were adjusted for age and MR scanner field strength. Larger volumes of the T2 hyperintensity lesion (T2ALL) and nonenhancing lesion (NEL) at pre-RT, as well as increased anatomic volumes at post-RT, were associated with worse overall survival (OS). Higher normalized cerebral blood volumes (nCBVs), normalized peak height (nPH) and normalized recirculation factors (nRF) at pre-RT, and nCBV at post-RT, in the T2ALL and NEL, were associated with shorter progression-free survival (PFS). From pre- to post-RT, there was a reduction in nCBV and nPH and an increase in apparent diffusion coefficient (ADC). Patients with lower nRF values at pre-RT, or a larger increase in nRF from pre-RT to post-RT, had significantly longer PFS. Time-dependent analysis showed that patterns of changes in ADC and anatomic volumes were associated with OS, while changes in nCBV, nPH, and the contrast-enhancing volume were associated with PFS. Our studies suggest that quantitative MRI variables derived from anatomic and physiological MRI provide useful information for predicting outcome in patients with GBM. PMID:21297128

Li, Yan; Lupo, Janine M.; Polley, Mei-Yin; Crane, Jason C.; Bian, Wei; Cha, Soonmee; Chang, Susan; Nelson, Sarah J.

2011-01-01

313

Head model and electrical source imaging: a study of 38 epileptic patients.  

PubMed

Electrical source imaging (ESI) aims at reconstructing the electrical brain activity from scalp EEG. When applied to interictal epileptiform discharges (IEDs), this technique is of great use for identifying the irritative zone in focal epilepsies. Inaccuracies in the modeling of electro-magnetic field propagation in the head (forward model) may strongly influence ESI and lead to mislocalization of IED generators. However, a systematic study on the influence of the selected head model on the localization precision of IED in a large number of patients with known focus localization has not yet been performed. We here present such a performance evaluation of different head models in a dataset of 38 epileptic patients who have undergone high-density scalp EEG, intracranial EEG and, for the majority, subsequent surgery. We compared ESI accuracy resulting from three head models: a Locally Spherical Model with Anatomical Constraints (LSMAC), a Boundary Element Model (BEM) and a Finite Element Model (FEM). All of them were computed from the individual MRI of the patient and ESI was performed on averaged IED. We found that all head models provided very similar source locations. In patients having a positive post-operative outcome, at least 74% of the source maxima were within the resection. The median distance from the source maximum to the nearest intracranial electrode showing IED was 13.2, 15.6 and 15.6 mm for LSMAC, BEM and FEM, respectively. The study demonstrates that in clinical applications, the use of highly sophisticated and difficult to implement head models is not a crucial factor for an accurate ESI. PMID:25003030

Birot, Gwénael; Spinelli, Laurent; Vulliémoz, Serge; Mégevand, Pierre; Brunet, Denis; Seeck, Margitta; Michel, Christoph M

2014-01-01

314

EVOLUTION OF TUMEFACTIVE LESIONS IN MULTIPLE SCLEROSIS: A 12-YEAR STUDY WITH SERIAL IMAGING IN A SINGLE PATIENT  

PubMed Central

Objective We describe the acute presentation and the long-term evolution of recurrent tumefactive lesions (TLs) in a patient with relapsing-remitting multiple sclerosis. Background Five TLs occurred at three separate timepoints over 12 years and these were followed by 73 serial magnetic resonance images. Methods TL evolution was described by means of magnetization transfer (MT) imaging and cerebrospinal fluid tissue specific imaging (TSI) over the period of the follow-up. Results During the study period, the patient had three clinical relapses with only minimal disability progression. MT imaging demonstrated that only the peripheral portion of each TL reverted to pre-lesional MT ratios within six months post-enhancement. Conclusions Recurring TLs may present a similar pattern of recovery that may be associated with a long-term favorable clinical outcome. PMID:24062416

Ikonomidou, Vasiliki N.; Richert, Nancy D.; Vortmeyer, Alexander; Tovar-Moll, Fernanda; Bielekova, Bibiana; Cook, Natalie E.; Duyn, Jeff H.; Bagnato, Francesca

2013-01-01

315

Multidimensional body image comparisons among patients with eating disorders, body dysmorphic disorder, and clinical controls: a multisite study.  

PubMed

Body image disturbance is considered a core characteristic of eating disorders and body dysmorphic disorder (BDD), however its definition has been unclear within the literature. This study examined the multidimensional nature of body image functioning among individuals with either anorexia nervosa (AN; n=35), bulimia nervosa (BN; n=26), or BDD (n=56), relative to female (n=34) and male (n=36) psychiatric controls. Participants were recruited from 10 treatment centers in the United States and England and completed psychometrically validated and standardized self-report measures of body image. Overall, the AN, BN, and BDD groups were characterized by significantly elevated disturbances in most body image dimensions relative to their gender-matched clinical controls. There was variability, however, in the comparisons among the three groups of interest, including foci of body dissatisfaction and body image coping patterns. On omnibus indices of body image disturbance and body image quality of life, patients with BDD reported more body image impairment than those with eating disorders. Although AN, BN, and BDD are characterized by body image disturbances, similar and partially distinctive cognitive, behavioral, and emotional elements of body image functioning exist among these groups. The study's empirical and clinical implications are considered. PMID:19410528

Hrabosky, Joshua I; Cash, Thomas F; Veale, David; Neziroglu, Fugen; Soll, Elizabeth A; Garner, David M; Strachan-Kinser, Melissa; Bakke, Bette; Clauss, Laura J; Phillips, Katharine A

2009-06-01

316

Calyceal Diverticulum of the Kidney – Diagnostic Imaging Dilemma in Pediatric Patients – Case Report  

PubMed Central

Summary Background Calyceal diverticula are rarely diagnosed in children. They can mimic other renal cystic lesions and correct diagnosis can be difficult to establish. Connection between fluid collection and collecting system confirmed by imaging studies is the key diagnostic finding. Case Report In this report we present a case of pediatric patient with calyceal diverticulum, with initial ultrasonographic diagnosis of simple renal cyst. Final diagnosis was established after extended diagnostics following infection of a fluid collection. Conclusions 1. Differential diagnosis of well-circumscribed solitary renal fluid collections in children should include particularly: simple cyst, calyceal diverticulum and the first demonstration of ADPKD. 2. Diagnosis of calyceal diverticulum should be confirmed by contrast studies. 3. Standard management of calyceal diverticula in children includes ultrasonographic follow-up and conservative treatment and rarely requires surgical intervention. PMID:25610511

Bombi?ski, Przemys?aw; Warcho?, Stanis?aw; Brzewski, Micha?; Biejat, Agnieszka; Dudek-Warcho?, Teresa; Krzemie?, Gra?yna; Szmigielska, Agnieszka; Toth, Krzysztof

2015-01-01

317

Impact of total activity variation in 18F-FDG injected with the overall PET image quality in oncology patients  

NASA Astrophysics Data System (ADS)

The preliminary study aims to investigate whether variation on dose activity 18F-FDG will influence the overall PET image quality in oncology patients. This is a retrospective analysis of 10 oncology patients who were injected with an average of 337.40 ± 38.43 MBq of 18F-FDG for PET/CT whole body examination. Patients were divided into 2 groups based on total activity of 18F-FDG injected: less than 333 MBq (302.96±12.65 MBq) (group 1) and more than 333 MBq (371.85±14.00 MBq) (group 2). Multiple Image Projection (MIP) PET images were scored visually by two qualified nuclear radiologists using a two-point scoring scale (poor and excellent). The agreement between radiologists was analysed using kappa measure of agreement (K). The prediction on poor-to-excellent PET image by the total activity of 18F-FDG injected was analysed using a Chi-squared test (x2). A p value of < 0.05 was considered significant. Agreement on PET image scoring was substantial, with a kappa value of 0.737. However, the prediction of the PET image quality by the total activity injected has been found to be insignificant (p > 0.05). Therefore, there is no strong evidence suggest that the dose injected will influence the PET image quality. Hence, it is recommended to use low-dosed of 18F-FDG technique as it also potentially yields a comparable PET image and reduces radiation burden to the patients.

Hishar, H.; Fathinul Fikri, A. S.; Salasiah, M.; Noramaliza, M. N.; Abdul Jalil, N.

2013-05-01

318

Retrospective versus prospective ECG-gated dual-source CT in pediatric patients with congenital heart diseases: comparison of image quality and radiation dose  

Microsoft Academic Search

We wanted to compare the image quality and radiation dose of retrospective versus prospective ECG-gated dual-source CT imaging\\u000a in pediatric patients with congenital heart diseases. We retrospectively evaluated 44 thorax CT images that were obtained\\u000a using two different protocols (retrospective helical ECG-gated [n = 22] versus prospective non-helical ECG-triggering [n = 22]) in patients younger than 5 years. Two radiologists evaluated the image quality, using

Kwang Nam Jin; Eun-Ah Park; Cheong-il Shin; Whal Lee; Jin Wook Chung; Jae Hyung Park

2010-01-01

319

The Palliative care has an expanding future in the heart of health care in New Zealand. It is founded on an interdisciplinary, patient centered model of care delivered in people's homes, hospice,  

E-print Network

The Palliative care has an expanding future in the heart of health care in New Zealand Diploma in Health Sciences (Palliative Care) This qualification consists of four papers, HLTH401: Health and Health Systems, HLTH450: Palliative Care: Advanced theory and practice, Students who have the Whitiriea

Hickman, Mark

320

Three-dimensional brain metabolic imaging in patients with toxic encephalopathy  

SciTech Connect

Thirty-three workers, ages 24 to 63, developed clinical toxic encephalopathy after exposure to neurotoxins and were studied by SPECT brain scans. Five were exposed to pesticides, 13 were acutely exposed to mixtures of solvents, 8 were chronically exposed to mixtures of hazardous wastes that contained organic solvents, 2 were acutely exposed to phosgene and other toxins, and 5 had exposures to hydrogen sulfide. Twenty-nine had neuropsychological testing and all had a medical history and physical. Of the workers who had a clinical diagnosis of toxic encephalopathy, 31 (93.9%) had abnormal SPECT brain scans with the most frequent areas of abnormality being temporal lobes (67.7%), frontal lobes (61.3%), basal ganglia (45.2%), thalamus (29.0%), parietal lobes (12.9%), motorstrip (9.68%), cerebral hemisphere (6.45%), occipital lobes (3.23%), and caudate nucleus (3.23%). Twenty-three out of 29 (79.3%) neuropsychological evaluations were abnormal. Other modalities when performed included the following percentages of abnormals: NCV, 33.3%; CPT sensory nerve testing, 91.3%, vestibular function testing, 71.4%; olfactory testing, 89.2%; sleep EEG analysis, 85.7%; EEG, 8.33%; CT, 7.14%; and MRI brain scans, 28.6%. The complex of symptoms seen in toxic encephalopathy implies dysfunction involving several CNS regions. This series of patients adds to the previous experience of brain metabolic imaging and demonstrates that certain areas of the brain are typically affected despite differences in toxin structure, that these lesions can be globally defined by SPECT/PET brain scans, that these lesions correlate well with clinical and neuropsychological testing, and that such testing is a useful adjunct to previous methods. EEG and structural brain imaging such as CT and MRI are observed to have poor sensitivity in this type of patient. 32 refs., 5 tabs.

Callender, T.J.; Duhon, D.; Ristovv, M. (Med-Health, Ltd. Clinic, Lafayette, LA (United States)); Morrow, L. (Univ. of Pittsburgh, PA (United States)); Subramanian, K. (Lafayette General Hospital, LA (United States))

1993-02-01

321

Magnetic Resonance Imaging Profile of Blood–Brain Barrier Injury in Patients With Acute Intracerebral Hemorrhage  

PubMed Central

Background Spontaneous intracerebral hemorrhage (ICH) is associated with blood–brain barrier (BBB) injury, which is a poorly understood factor in ICH pathogenesis, potentially contributing to edema formation and perihematomal tissue injury. We aimed to assess and quantify BBB permeability following human spontaneous ICH using dynamic contrast?enhanced magnetic resonance imaging (DCE MRI). We also investigated whether hematoma size or location affected the amount of BBB leakage. Methods and Results Twenty?five prospectively enrolled patients from the Diagnostic Accuracy of MRI in Spontaneous intracerebral Hemorrhage (DASH) study were examined using DCE MRI at 1 week after symptom onset. Contrast agent dynamics in the brain tissue and general tracer kinetic modeling were used to estimate the forward leakage rate (Ktrans) in regions of interest (ROI) in and surrounding the hematoma and in contralateral mirror–image locations (control ROI). In all patients BBB permeability was significantly increased in the brain tissue immediately adjacent to the hematoma, that is, the hematoma rim, compared to the contralateral mirror ROI (P<0.0001). Large hematomas (>30 mL) had higher Ktrans values than small hematomas (P<0.005). Ktrans values of lobar hemorrhages were significantly higher than the Ktrans values of deep hemorrhages (P<0.005), independent of hematoma volume. Higher Ktrans values were associated with larger edema volumes. Conclusions BBB leakage in the brain tissue immediately bordering the hematoma can be measured and quantified by DCE MRI in human ICH. BBB leakage at 1 week is greater in larger hematomas as well as in hematomas in lobar locations and is associated with larger edema volumes. PMID:23709564

Aksoy, Didem; Bammer, Roland; Mlynash, Michael; Venkatasubramanian, Chitra; Eyngorn, Irina; Snider, Ryan W.; Gupta, Sandeep N.; Narayana, Rashmi; Fischbein, Nancy; Wijman, Christine A. C.

2013-01-01

322

Temporomandibular joints in patients with rheumatoid arthritis using magnetic resonance imaging.  

PubMed

The aim of this study was to determine the relationship between the pathogenic duration of rheumatoid arthritis in joints other than the temporomandibular joint and bone and soft tissue involvement of the temporomandibular joint using magnetic resonance imaging. Twenty-six symptomatic patients diagnosed with rheumatoid arthritis were enrolled in this study. All patients were classified according to the duration of rheumatoid arthritis in joints other than the temporomandibular joint. The relationships between the duration of rheumatoid arthritis in these various joints and magnetic resonance findings in the temporomandibular joint were analyzed using the chi-square test. Bony changes in the mandibular condyle were observed in 43 of 52 (82.7 %) temporomandibular joints, but the frequency of such changes was not significantly correlated with the duration of rheumatoid arthritis in other joints. We found a significant correlation between the duration of rheumatoid arthritis in other joints and the type and number of bony changes in the mandibular condyle (P?images demonstrated effusion in the joint space in 38 of 52 (73.1 %) temporomandibular joints. A biplanar disc configuration was the most frequent configuration in all groups. The duration of rheumatoid arthritis in other joints was significantly correlated with the mobility of the mandibular condyle (P?

Uchiyama, Yuka; Murakami, Shumei; Furukawa, Souhei

2013-11-01

323

Imaging tumour heterogeneity of the consequences of a PKC?-substrate interaction in breast cancer patients.  

PubMed

Breast cancer heterogeneity demands that prognostic models must be biologically driven and recent clinical evidence indicates that future prognostic signatures need evaluation in the context of early compared with late metastatic risk prediction. In pre-clinical studies, we and others have shown that various protein-protein interactions, pertaining to the actin microfilament-associated proteins, ezrin and cofilin, mediate breast cancer cell migration, a prerequisite for cancer metastasis. Moreover, as a direct substrate for protein kinase C?, ezrin has been shown to be a determinant of cancer metastasis for a variety of tumour types, besides breast cancer; and has been described as a pivotal regulator of metastasis by linking the plasma membrane to the actin cytoskeleton. In the present article, we demonstrate that our tissue imaging-derived parameters that pertain to or are a consequence of the PKC-ezrin interaction can be used for breast cancer prognostication, with inter-cohort reproducibility. The application of fluorescence lifetime imaging microscopy (FLIM) in formalin-fixed paraffin-embedded patient samples to probe protein proximity within the typically <10 nm range to address the oncological challenge of tumour heterogeneity, is discussed. PMID:25399560

Weitsman, Gregory; Lawler, Katherine; Kelleher, Muireann T; Barrett, James E; Barber, Paul R; Shamil, Eamon; Festy, Frederic; Patel, Gargi; Fruhwirth, Gilbert O; Huang, Lufei; Tullis, Iain D C; Woodman, Natalie; Ofo, Enyinnaya; Ameer-Beg, Simon M; Irshad, Sheeba; Condeelis, John; Gillett, Cheryl E; Ellis, Paul A; Vojnovic, Borivoj; Coolen, Anthony C C; Ng, Tony

2014-12-01

324

Automated segmentation of outer retinal layers in macular OCT images of patients with retinitis pigmentosa  

PubMed Central

To provide a tool for quantifying the effects of retinitis pigmentosa (RP) seen on spectral domain optical coherence tomography images, an automated layer segmentation algorithm was developed. This algorithm, based on dual-gradient information and a shortest path search strategy, delineates the inner limiting membrane and three outer retinal boundaries in optical coherence tomography images from RP patients. In addition, an automated inner segment (IS)/outer segment (OS) contour detection method based on the segmentation results is proposed to quantify the locus of points at which the OS thickness goes to zero in a 3D volume scan. The segmentation algorithm and the IS/OS contour were validated with manual segmentation data. The segmentation and IS/OS contour results on repeated measures showed good within-day repeatability, while the results on data acquired on average 22.5 months afterward demonstrated a possible means to follow disease progression. In particular, the automatically generated IS/OS contour provided a possible objective structural marker for RP progression. PMID:21991543

Yang, Qi; Reisman, Charles A.; Chan, Kinpui; Ramachandran, Rithambara; Raza, Ali; Hood, Donald C.

2011-01-01

325

Measuring the relative extent of pulmonary infiltrates by hierarchical classification of patient-specific image features  

NASA Astrophysics Data System (ADS)

Pulmonary infiltrates are common radiological findings indicating the filling of airspaces with fluid, inflammatory exudates, or cells. They are most common in cases of pneumonia, acute respiratory syndrome, atelectasis, pulmonary oedema and haemorrhage, whereas their extent is usually correlated with the extent or the severity of the underlying disease. In this paper we propose a novel pattern recognition framework for the measurement of the extent of pulmonary infiltrates in routine chest radiographs. The proposed framework follows a hierarchical approach to the assessment of image content. It includes the following: (a) sampling of the lung fields; (b) extraction of patient-specific grey-level histogram signatures from each sample; (c) classification of the extracted signatures into classes representing normal lung parenchyma and pulmonary infiltrates; (d) the samples for which the probability of belonging to one of the two classes does not reach an acceptable level are rejected and classified according to their textural content; (e) merging of the classification results of the two classification stages. The proposed framework has been evaluated on real radiographic images with pulmonary infiltrates caused by bacterial infections. The results show that accurate measurements of the infiltration areas can be obtained with respect to each lung field area. The average measurement error rate on the considered dataset reached 9.7% ± 1.0%.

Tsevas, S.; Iakovidis, D. K.

2011-11-01

326

Imaging tumour heterogeneity of the consequences of a PKC?–substrate interaction in breast cancer patients  

PubMed Central

Breast cancer heterogeneity demands that prognostic models must be biologically driven and recent clinical evidence indicates that future prognostic signatures need evaluation in the context of early compared with late metastatic risk prediction. In pre-clinical studies, we and others have shown that various protein–protein interactions, pertaining to the actin microfilament-associated proteins, ezrin and cofilin, mediate breast cancer cell migration, a prerequisite for cancer metastasis. Moreover, as a direct substrate for protein kinase C?, ezrin has been shown to be a determinant of cancer metastasis for a variety of tumour types, besides breast cancer; and has been described as a pivotal regulator of metastasis by linking the plasma membrane to the actin cytoskeleton. In the present article, we demonstrate that our tissue imaging-derived parameters that pertain to or are a consequence of the PKC–ezrin interaction can be used for breast cancer prognostication, with inter-cohort reproducibility. The application of fluorescence lifetime imaging microscopy (FLIM) in formalin-fixed paraffin-embedded patient samples to probe protein proximity within the typically <10 nm range to address the oncological challenge of tumour heterogeneity, is discussed. PMID:25399560

Weitsman, Gregory; Lawler, Katherine; Kelleher, Muireann T.; Barrett, James E.; Barber, Paul R.; Shamil, Eamon; Festy, Frederic; Patel, Gargi; Fruhwirth, Gilbert O.; Huang, Lufei; Tullis, Iain D.C.; Woodman, Natalie; Ofo, Enyinnaya; Ameer-Beg, Simon M.; Irshad, Sheeba; Condeelis, John; Gillett, Cheryl E.; Ellis, Paul A.; Vojnovic, Borivoj; Coolen, Anthony C.C.; Ng, Tony

2014-01-01

327

IMAGES, IMAGES, IMAGES  

SciTech Connect

The role of images of information (charts, diagrams, maps, and symbols) for effective presentation of facts and concepts is expanding dramatically because of advances in computer graphics technology, increasingly hetero-lingual, hetero-cultural world target populations of information providers, the urgent need to convey more efficiently vast amounts of information, the broadening population of (non-expert) computer users, the decrease of available time for reading texts and for decision making, and the general level of literacy. A coalition of visual performance experts, human engineering specialists, computer scientists, and graphic designers/artists is required to resolve human factors aspects of images of information. The need for, nature of, and benefits of interdisciplinary effort are discussed. The results of an interdisciplinary collaboration are demonstrated in a product for visualizing complex information about global energy interdependence. An invited panel will respond to the presentation.

Marcus, A.

1980-07-01

328

Proton magnetic resonance spectroscopic imaging in the clinical evaluation of patients with Niemann-Pick type C disease  

Microsoft Academic Search

OBJECTIVES10 patients with Niemann-Pick disease type C (NP-C) were studied by proton magnetic resonance spectroscopic imaging (1H-MRSI) to assess the biochemical pathology of the brain and to determine whether this method can be useful to clinically evaluate these patients.METHODS1H-MRSI permits the simultaneous measurement of N-acetyl aspartate (NA), compounds containing choline (Cho), creatine plus phosphocreatine (Cre), and lactate (Lac) signal intensities

G Tedeschi; S Bonavita; N W Barton; A Bertolino; J A Frank; N J Patronas; J R Alger; R Schiffmann

1998-01-01

329

Discrepant 99mTc-ECD images of CBF in patients with subacute cerebral infarction: a comparison of CBF, CMRO2 and 99mTc-HMPAO imaging.  

PubMed

Three patients with subacute ischemic cerebral infarction examined by SPECT with 99mTc-ECD and PET within the same day showed signs of luxury perfusion in the subacute phase, which is between 9 to 20 days after the onset. A 99mTc-HMPAO SPECT study was also performed within 2 days of the ECD-SPECT study. ECD-SPECT images of three patients displayed a focal decreased uptake in the infarcted lesions, while in infarcted foci, there was almost equivalent or increased CBF compared to normal and unaffected areas, decreased CMRO2, and high HMPAO uptake. The ECD-SPECT results were similar to those of CMRO2 rather than CBF, though the HMPAO-SPECT image was similar to that of CBF. In one patient, HMPAO images revealed hyperfixation of the tracer. In the chronic phase and in the acute phase before 5 days after the onset, there were no discrepancies among the ECD-SPECT, CBF, HMPAO-SPECT, and CMRO2 images. These observations indicated that 99mTc-ECD is a good indicator of damaged brain tissues in subacute ischemic infarction. They also suggested that 99mTc-ECD is a potential agent with which to evaluate cerebral tissue viability in some pathological states of cerebrovascular disease. The characteristics may be suitable for confirming the effects of thrombolytic therapy in acute ischemia, because these conditions often show signs of luxury perfusion when the therapy is successful. PMID:8534592

Shishido, F; Uemura, K; Inugami, A; Ogawa, T; Fujita, H; Shimosegawa, E; Nagata, K

1995-08-01

330

Volume measurement of bone erosions in magnetic resonance images of patients with rheumatoid arthritis.  

PubMed

The volume of bone erosions in the metacarpophalangeal joints is a radiological feature that can be used to track the progression of rheumatoid arthritis. We introduce a hybrid segmentation algorithm that combines region growing and level-set segmentation algorithms to semiautomatically measure the volume of bone erosions in magnetic resonance images. A total of 40 rheumatoid arthritis patients were included in the study. The scans of eight patients were used for training, whereas the remaining 32 scans were used to determine the accuracy, precision, and speed of the technique. The reproducibility of the semiautomated technique and that of manual segmentation was defined in terms of intraclass correlation coefficients. Both techniques were equally precise with intraclass correlation coefficient values greater than 0.9. The hybrid algorithm was highly accurate: the least squares fit between the semiautomated segmentations to those manually traced by a musculoskeletal radiologist resulted in a slope of 1.030 with an x-intercept of 1.385 mm(3) and an R(2) value of 0.923. The semiautomated technique was significantly faster than manual segmentation, which took two to four times longer to complete. Our hybrid algorithm shows promise in the quantitative assessment of radiological features of rheumatoid arthritis in a clinical setting. PMID:21688319

Emond, P D; Inglis, D; Choi, A; Tricta, J; Adachi, J D; Gordon, C L

2012-03-01

331

Advanced magnetic resonance imaging methods for planning and monitoring radiation therapy in patients with high-grade glioma.  

PubMed

This review explores how the integration of advanced imaging methods with high-quality anatomical images significantly improves the characterization, target definition, assessment of response to therapy, and overall management of patients with high-grade glioma. Metrics derived from diffusion-, perfusion-, and susceptibility-weighted magnetic resonance imaging in conjunction with magnetic resonance spectroscopic imaging, allows us to characterize regions of edema, hypoxia, increased cellularity, and necrosis within heterogeneous tumor and surrounding brain tissue. Quantification of such measures may provide a more reliable initial representation of tumor delineation and response to therapy than changes in the contrast-enhancing or T2 lesion alone and have a significant effect on targeting resection, planning radiation, and assessing treatment effectiveness. In the long term, implementation of these imaging methodologies can also aid in the identification of recurrent tumor and its differentiation from treatment-related confounds and facilitate the detection of radiationinduced vascular injury in otherwise normal-appearing brain tissue. PMID:25219809

Lupo, Janine M; Nelson, Sarah J

2014-10-01

332

Feasibility study of patient positioning verification in electron beam radiotherapy with an electronic portal imaging device (EPID).  

PubMed

The purpose of this study is to demonstrate the feasibility of verification and documentation in electron beam radiotherapy using the photon contamination detected with an electronic portal imaging device. For investigation of electron beam verification with an EPID, the portal images are acquired irradiating two different tissue equivalent phantoms at different electron energies. Measurements were performed on an Elekta SL 25 linear accelerator with an amorphous-Si electronic portal imaging device (EPID: iViewGT, Elekta Oncology Systems, Crawley, UK). As a measure of EPID image quality contrast (CR) and signal-to-noise ratio (SNR) are determined. For characterisation of the imaging of the EPID RW3 slabs and a Gammex 467 phantom with different material inserts are used. With increasing electron energy the intensity of photon contamination increases, yielding an increasing signal-to-noise ratio, but images are showing a decreasing contrast. As the signal-to-noise ratio saturates with increasing dose a minimum of 50 MUs is recommended. Even image quality depends on electron energy and diameter of the patient, the acquired results are mostly sufficient to assess the accuracy of beam positioning. In general, the online EPID acquisition has been demonstrated to be an effective electron beam verification and documentation method. The results are showing that this procedure can be recommended to be routinely and reliably done in patient treatment with electron beams. PMID:23850512

Ramm, U; Köhn, J; Rodriguez Dominguez, R; Licher, J; Koch, N; Kara, E; Scherf, C; Rödel, C; Weiß, C

2014-03-01

333

Selecting a Variable for Predicting the Diagnosis of PTB Patients From Comparison of Chest X-ray Images  

NASA Astrophysics Data System (ADS)

A statistical method of comparing two digital chest radiographs for Pulmonary Tuberculosis (PTB) patients has been proposed. After applying appropriate image registration procedures, a selected subset of each image is converted to an image histogram (or box plot). Comparing two chest X-ray images is equivalent to the direct comparison of the two corresponding histograms. From each histogram, eleven percentiles (of image intensity) are calculated. The number of percentiles that shift to the left (NLSP) when second image is compared to the first has been shown to be an indicator of patients` progress. In this study, the values of NLSP is to be compared with the actual diagnosis (Y) of several medical practitioners. A logistic regression model is used to study the relationship between NLSP and Y. This study showed that NLSP may be used as an alternative or second opinion for Y. The proposed regression model also show that important explanatory variables such as outcomes of sputum test (Z) and degree of image registration (W) may be omitted when estimating Y-values.

Mohd. Rijal, Omar; Mohd. Noor, Norliza; Teng, Shee Lee

334

Counterview: Pre-operative breast MRI (magnetic resonance imaging) is not recommended for all patients with newly diagnosed breast cancer.  

PubMed

For the woman with a newly diagnosed early stage breast cancer, the routine use of pre-operative breast MRI (magnetic resonance imaging) is not indicated beyond conventional breast imaging (i.e., mammography with correlation ultrasound as indicated). There is no consistent evidence that a pre-operative breast MRI confers a benefit to the patient by improving clinical outcomes or surgical procedures. In a meta-analysis of studies reporting on the use of pre-operative breast MRI for the patient with an established index cancer, multifocal or multicentric disease was found on breast MRI in 16% of the patients, a rate substantially higher than the rate of local recurrence after breast conserving surgery plus definitive radiation treatment. In the largest retrospective study of patients treated with breast conserving surgery plus radiation, no gain was found for adding a breast MRI to conventional breast imaging. No randomized clinical trial has been designed to evaluate long term clinical outcomes associated with adding a pre-operative breast MRI. Adding pre-operative breast MRI can alter clinical management in ways that are potentially harmful to patients, for example, increased ipsilateral mastectomies, increased contralateral prophylactic mastectomies, increased work-ups, and delay to definitive surgery. In summary, the routine use of pre-operative breast MRI is not warranted for the typical patient with a newly diagnosed early stage breast cancer. PMID:20159457

Solin, Lawrence J

2010-02-01

335

Frontal White Matter Alterations in Short-Term Medicated Panic Disorder Patients without Comorbid Conditions: A Diffusion Tensor Imaging Study  

PubMed Central

The frontal cortex might play an important role in the fear network, and white matter (WM) integrity could be related to the pathophysiology of panic disorder (PD). A few studies have investigated alterations of WM integrity in PD. The aim of this study was to determine frontal WM integrity differences between patients with PD without comorbid conditions and healthy control (HC) subjects by using diffusion tensor imaging. Thirty-six patients with PD who had used medication within 1 week and 27 age- and sex-matched HC subjects participated in this study. Structural brain magnetic resonance imaging was performed on all participants. Panic Disorder Severity Scale and Beck Anxiety Inventory (BAI) scores were assessed. Tract-based spatial statistics (TBSS) was used for image analysis. TBSS analysis showed decreased fractional anisotropy (FA) in frontal WM and WM around the frontal lobe, including the corpus callosum of both hemispheres, in patients with PD compared to HC subjects. Moreover, voxel-wise correlation analysis revealed that the BAI scores for patients with PD were positively correlated with their FA values for regions showing group differences in the FA of frontal WM of both hemispheres. Altered integrity in frontal WM of patients with PD without comorbid conditions might represent the structural pathophysiology in these patients, and these changes could be related to clinical symptoms of PD. PMID:24788587

Kim, Borah; Kim, Jeong Hoon; Kim, Min-Kyoung; Lee, Kang Soo; Kim, Youngki; Choi, Tai Kiu; Kim, Yun Tai; Lee, Sang-Hyuk

2014-01-01

336

Increased Protein Stability of CDKN1C Causes a Gain-of-Function Phenotype in Patients with IMAGe Syndrome  

PubMed Central

Mutations in the proliferating cell nuclear antigen (PCNA)-binding domain of the CDKN1C gene were recently identified in patients with IMAGe syndrome. However, loss of PCNA binding and suppression of CDKN1C monoubiquitination by IMAGe-associated mutations hardly explain the reduced-growth phenotype characteristic of IMAGe syndrome. We demonstrate here that IMAGe-associated mutations in the CDKN1C gene dramatically increased the protein stability. We identified a novel heterozygous mutation, c.815T>G (p.Ile272Ser), in the CDKN1C gene in three siblings manifesting clinical symptoms associated with IMAGe syndrome and their mother (unaffected carrier). PCNA binding to CDKN1C was disrupted in the case of p.Ile272Ser, and for two other IMAGe-associated mutations, p.Asp274Asn and p.Phe276Val. Intriguingly, the IMAGe-associated mutant CDKN1C proteins were fairly stable even in the presence of cycloheximide, whereas the wild-type protein was almost completely degraded via the proteasome pathway, as shown by the lack of degradation with addition of a proteasome inhibitor, MG132. These results thus suggested that the reduced-growth phenotype of IMAGe syndrome derives from CDKN1C gain-of-function due to IMAGe-associated mutations driving increased protein stability. PMID:24098681

Hamajima, Naoki; Johmura, Yoshikazu; Suzuki, Satoshi; Nakanishi, Makoto; Saitoh, Shinji

2013-01-01

337

The limit of detection in scintigraphic imaging with I-131 in patients with differentiated thyroid carcinoma  

NASA Astrophysics Data System (ADS)

Radioiodine scintigraphy influences staging and treatment in patients with differentiated thyroid carcinoma. The limit of detection for fractional uptake in an iodine avid focus in a scintigraphic image was determined from the number of lesion net counts and the count density of the tissue background. The count statistics were used to calculate the diagnostic activity required to elevate the signal from a lesion with a given uptake significantly above a homogeneous background with randomly distributed counts per area. The dependences of the minimal uptake and the minimal size of lesions visible in a scan on several parameters of influence were determined by linking the typical biokinetics observed in iodine avid tissue to the lesion mass and to the absorbed dose received in a radioiodine therapy. The detection limits for fractional uptake in a neck lesion of a typical patient are about 0.001% after therapy with 7000 MBq, 0.01% for activities typically administered in diagnostic assessments (74-185 MBq), and 0.1% after the administration of 10 MBq I-131. Lesions at the limit of detection in a diagnostic scan with biokinetics eligible for radioiodine therapy are small with diameters of a few millimeters. Increasing the diagnostic activity by a factor of 4 reduces the diameter of visible lesions by 25% or about 1 mm. Several other determinants have a comparable or higher influence on the limit of detection than the administered activity; most important are the biokinetics in both blood pool and target tissue and the time of measurement. A generally valid recommendation for the timing of the scan is impossible as the time of the highest probability to detect iodine avid tissue depends on the administered activity as well as on the biokinetics in the lesion and background in the individual patient.

Hänscheid, H.; Lassmann, M.; Buck, A. K.; Reiners, C.; Verburg, F. A.

2014-05-01

338

Longitudinal diffusion tensor imaging and neuropsychological correlates in traumatic brain injury patients  

PubMed Central

Traumatic brain injury (TBI) often involves focal cortical injury and white matter (WM) damage that can be measured shortly after injury. Additionally, slowly evolving WM change can be observed but there is a paucity of research on the duration and spatial pattern of long-term changes several years post-injury. The current study utilized diffusion tensor imaging to identify regional WM changes in 12 TBI patients and nine healthy controls at three time points over a four year period. Neuropsychological testing was also administered to each participant at each time point. Results indicate that TBI patients exhibit longitudinal changes to WM indexed by reductions in fractional anisotropy (FA) in the corpus callosum, as well as FA increases in bilateral regions of the superior longitudinal fasciculus (SLF) and portions of the optic radiation (OR). FA changes appear to be driven by changes in radial (not axial) diffusivity, suggesting that observed longitudinal FA changes may be related to changes in myelin rather than to axons. Neuropsychological correlations indicate that regional FA values in the corpus callosum and sagittal stratum (SS) correlate with performance on finger tapping and visuomotor speed tasks (respectively) in TBI patients, and that longitudinal increases in FA in the SS, SLF, and OR correlate with improved performance on the visuomotor speed (SS) task as well as a derived measure of cognitive control (SLF, OR). The results of this study showing progressive WM deterioration for several years post-injury contribute to a growing literature supporting the hypothesis that TBI should be viewed not as an isolated incident but as a prolonged disease state. The observations of long-term neurological and functional improvement provide evidence that some ameliorative change may be occurring concurrently with progressive degeneration. PMID:22723773

Farbota, Kimberly D.; Bendlin, Barbara B.; Alexander, Andrew L.; Rowley, Howard A.; Dempsey, Robert J.; Johnson, Sterling C.

2012-01-01

339

A modified VMAT adaptive radiotherapy for nasopharyngeal cancer patients based on CT-CT image fusion  

PubMed Central

Background To investigate the feasibility and benefits of a modified adaptive radiotherapy (ART) by replanning in the initial CT (iCT) with new contours from a repeat CT (rCT) based on CT-CT image fusion for nasopharyngeal cancer (NPC) patients underwent volumetric modulated arc radiotherapy (VMAT). Materials and methods Nine NPC patients underwent VMAT treatment with a rCT at 23rd fraction were enrolled in this study. Dosimetric differences for replanning VMAT plans in the iCT and in the rCT were compared. Volumetric and dosimetric changes of gross tumor volume (GTV) and organs at risk (OARs) of this modified ART were also investigated. Results No dosimetric differences between replanning in the iCT and in the rCT were observed. The average volume of GTV decreased from 78.83?±?38.42 cm3 in the iCT to 71.44?±?37.46 cm3 in the rCT, but with no significant difference (p?=?0.42).The average volume of the left and right parotid decreased from 19.91?±?4.89 cm3 and 21.58?±?6.16 cm3 in the iCT to 11.80?±?2.79 cm3 and 13.29?±?4.17 cm3 in the rCT (both p?Patients with NPC undergoing VMAT have significant anatomic and dosimetric changes to parotids. Repeat CT as an anatomic changes reference and re-optimization in the iCT based on CT-CT image fusion was accurate enough to identify the volume changes and to ensure safe dose to parotids. PMID:24279414

2013-01-01

340

Characterization of mammographic masses based on level set segmentation with new image features and patient information  

SciTech Connect

Computer-aided diagnosis (CAD) for characterization of mammographic masses as malignant or benign has the potential to assist radiologists in reducing the biopsy rate without increasing false negatives. The purpose of this study was to develop an automated method for mammographic mass segmentation and explore new image based features in combination with patient information in order to improve the performance of mass characterization. The authors' previous CAD system, which used the active contour segmentation, and morphological, textural, and spiculation features, has achieved promising results in mass characterization. The new CAD system is based on the level set method and includes two new types of image features related to the presence of microcalcifications with the mass and abruptness of the mass margin, and patient age. A linear discriminant analysis (LDA) classifier with stepwise feature selection was used to merge the extracted features into a classification score. The classification accuracy was evaluated using the area under the receiver operating characteristic curve. The authors' primary data set consisted of 427 biopsy-proven masses (200 malignant and 227 benign) in 909 regions of interest (ROIs) (451 malignant and 458 benign) from multiple mammographic views. Leave-one-case-out resampling was used for training and testing. The new CAD system based on the level set segmentation and the new mammographic feature space achieved a view-based A{sub z} value of 0.83{+-}0.01. The improvement compared to the previous CAD system was statistically significant (p=0.02). When patient age was included in the new CAD system, view-based and case-based A{sub z} values were 0.85{+-}0.01 and 0.87{+-}0.02, respectively. The study also demonstrated the consistency of the newly developed CAD system by evaluating the statistics of the weights of the LDA classifiers in leave-one-case-out classification. Finally, an independent test on the publicly available digital database for screening mammography with 132 benign and 197 malignant ROIs containing masses achieved a view-based A{sub z} value of 0.84{+-}0.02.

Shi Jiazheng; Sahiner, Berkman; Chan Heangping; Ge Jun; Hadjiiski, Lubomir; Helvie, Mark A.; Nees, Alexis; Wu Yita; Wei Jun; Zhou Chuan; Zhang Yiheng; Cui Jing [Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109-0904 (United States)

2008-01-15

341

Prognostic value of exercise stress technetium-99m-tetrofosmin myocardial perfusion imaging in patients with normal baseline electrocardiograms.  

PubMed

Exercise stress electrocardiography is the recommended method for cardiac evaluation of patients with normal electrocardiograms (ECGs). There are no data to indicate an independent value of myocardial perfusion imaging (MPI) in predicting mortality in these patients. This study assessed the value of exercise stress MPI in predicting mortality in patients with normal baseline ECGs. We studied 319 patients (55 +/- 10 years of age; 180 men) with normal ECGs by exercise stress technetium-99m tetrofosmin MPI. End points during follow-up were cardiac and all-cause mortalities and hard cardiac events. A normal scan was detected in 190 patients (60%). Myocardial perfusion abnormalities were fixed in 59 patients (18%) and reversible in 70 (23%). During a mean follow-up of 7 +/- 1.2 years, 46 patients (14%) died. Death was considered cardiac in 28 patients (9%). Nonfatal myocardial infarction occurred in 12 patients (4%). Annual cardiac death rates were 0.4% in patients with normal perfusion, and 2.7% in patients with reversible defects. Annual total mortality rates were 1.1% in patients with normal perfusion and 3.4% in patients with reversible defects. In a multivariate analysis model, reversible perfusion abnormalities were associated with cardiac death (RR 2.8, 95% confidence interval 1.6 to 5.1) and hard cardiac events (RR 2.7, 95% confidence interval 1.5 to 4.5). Perfusion abnormalities in multivessel distribution were predictive of all-cause mortality (RR 2, 95% confidence interval 1.4 to 3.2). ST-segment depression was not significantly associated with events. In conclusion, stress technetium-99m tetrofosmin MPI provides independent information for predicting cardiac and overall mortalities in patients with normal ECGs. Reversible perfusion abnormalities, but not ischemic electrocardiographic changes, are predictive of outcome in these patients. PMID:16923441

Elhendy, Abdou; Schinkel, Arend F L; van Domburg, Ron T; Bax, Jeroen J; Valkema, Roelf; Huurman, Aukje; Feringa, Harm H H; Poldermans, Don

2006-09-01

342

Diastolic Function in Several Stages of Chronic Kidney Disease in Patients with Autosomal Dominant Polycystic Kidney Disease: A Tissue Doppler Imaging Study  

Microsoft Academic Search

Background: This study evaluates the prevalence of diastolic dysfunction (DD) in several stages of chronic kidney disease (CKD) in patients with autosomal dominant polycystic kidney disease (ADPKD). Methods: 107 ADPKD patients performed echocardiographic and Doppler studies and a tissue Doppler imaging (TDI) study. Patients were divided in three groups: group 1, 57 patients with CKD stage I, group 2, 37

Edgar A. F. de Almeida; Eduardo I. de Oliveira; José António Lopes; Ana G. Almeida; Mário G. Lopes; M. Martins Prata

2007-01-01

343

Imaging characteristics of contralateral asymptomatic patellofemoral joints in patients with unilateral instability.  

PubMed

Purpose To test the hypothesis that in patients with unilateral patellofemoral instability ( PI patellofemoral instability ), the contralateral asymptomatic joints have abnormal morphology and imaging features of osteoarthritis ( OA osteoarthritis ) at four-dimensional ( 4D four-dimensional ) computed tomography (CT). Materials and Methods The institutional review board approved this HIPAA-compliant retrospective study. Informed consent was waived. Radiology records were reviewed to identify 25 patients (male-female ratio, 0.56; median age, 20 years; range, 13-43 years) with unilateral PI patellofemoral instability undergoing 4D four-dimensional CT and 25 age- and sex-matched control patients undergoing multidetector CT. Trochlear groove depth ( TGD trochlear groove depth ), tibial tuberosity-trochlear groove ( TT-TG tibial tuberosity-trochlear groove ) distance, and patellar height ratio ( PHR patellar height ratio ) were determined to compare morphology, and bisect offset ( BO bisect offset ) measurements were obtained to compare lateral displacement of the patella between the two groups by using the Wilcoxon rank-sum test. All images were interpreted by trained observers. Tracking patterns of the patellae were determined by obtaining BO bisect offset measurements at various flexion angles with 4D four-dimensional CT. Results In the contralateral asymptomatic joints, TGD trochlear groove depth (median, 3.0 mm; 95% confidence interval [ CI confidence interval ]: 2.5, 4.6; P < .0001), TT-TG tibial tuberosity-trochlear groove (median, 15 mm; 95% CI confidence interval : 12.7, 18; P = .008), PHR patellar height ratio (median, 1.17; 95% CI confidence interval : 1.09, 1.2; P = .002), and patellar lateral displacement ( BO bisect offset , 85%; 95% CI confidence interval : 76.2%, 98.2%; P < .0001) were different from measurements obtained in the control group: TGD trochlear groove depth median, 5.0 mm (95% CI confidence interval : 2.2, 7.6); TT-TG tibial tuberosity-trochlear groove median, 10.9 mm (95% CI confidence interval : 3.4, 20.7); PHR patellar height ratio median, 0.92 (95% CI confidence interval : 0.67, 1.36); and BO bisect offset median, 63% (95% CI confidence interval : 59%, 68.4%). OA osteoarthritis was detected in 40% of asymmetrical contralateral joints (10 of 25). By using 4D four-dimensional CT data, multiple regression analysis demonstrated that TGD trochlear groove depth (P = .026) and BO bisect offset measurements obtained at 30° of knee flexion (P = .047) had an association with the presence of OA osteoarthritis . Conclusion Abnormal morphology and imaging features of OA osteoarthritis are relatively common in contralateral asymptomatic joints of young patients with unilateral PI patellofemoral instability . © RSNA, 2014 Online supplemental material is available for this article. PMID:25153158

Demehri, Shadpour; Thawait, Gaurav K; Williams, Ariel A; Kompel, Andrew; Elias, John J; Carrino, John A; Cosgarea, Andrew J

2014-12-01

344

Intravenous administration of auto serum-expanded autologous mesenchymal stem cells in stroke.  

PubMed

Transplantation of human mesenchymal stem cells has been shown to reduce infarct size and improve functional outcome in animal models of stroke. Here, we report a study designed to assess feasibility and safety of transplantation of autologous human mesenchymal stem cells expanded in autologous human serum in stroke patients. We report an unblinded study on 12 patients with ischaemic grey matter, white matter and mixed lesions, in contrast to a prior study on autologous mesenchymal stem cells expanded in foetal calf serum that focused on grey matter lesions. Cells cultured in human serum expanded more rapidly than in foetal calf serum, reducing cell preparation time and risk of transmissible disorders such as bovine spongiform encephalomyelitis. Autologous mesenchymal stem cells were delivered intravenously 36-133 days post-stroke. All patients had magnetic resonance angiography to identify vascular lesions, and magnetic resonance imaging prior to cell infusion and at intervals up to 1 year after. Magnetic resonance perfusion-imaging and 3D-tractography were carried out in some patients. Neurological status was scored using the National Institutes of Health Stroke Scale and modified Rankin scores. We did not observe any central nervous system tumours, abnormal cell growths or neurological deterioration, and there was no evidence for venous thromboembolism, systemic malignancy or systemic infection in any of the patients following stem cell infusion. The median daily rate of National Institutes of Health Stroke Scale change was 0.36 during the first week post-infusion, compared with a median daily rate of change of 0.04 from the first day of testing to immediately before infusion. Daily rates of change in National Institutes of Health Stroke Scale scores during longer post-infusion intervals that more closely matched the interval between initial scoring and cell infusion also showed an increase following cell infusion. Mean lesion volume as assessed by magnetic resonance imaging was reduced by >20% at 1 week post-cell infusion. While we would emphasize that the current study was unblinded, did not assess overall function or relative functional importance of different types of deficits, and does not exclude placebo effects or a contribution of recovery as a result of the natural history of stroke, our observations provide evidence supporting the feasibility and safety of delivery of a relatively large dose of autologous mesenchymal human stem cells, cultured in autologous human serum, into human subjects with stroke and support the need for additional blinded, placebo-controlled studies on autologous mesenchymal human stem cell infusion in stroke. PMID:21493695

Honmou, Osamu; Houkin, Kiyohiro; Matsunaga, Takuya; Niitsu, Yoshiro; Ishiai, Sumio; Onodera, Rie; Waxman, Stephen G; Kocsis, Jeffery D

2011-06-01

345

The distance discordance metric - A novel approach to quantifying spatial uncertainties in intra- and inter-patient deformable image registration  

PubMed Central

Previous methods to estimate the inherent accuracy of deformable image registration (DIR) have typically been performed relative to a known ground truth, such as tracking of anatomic landmarks or known deformations in a physical or virtual phantom. In this study, we propose a new approach to estimate the spatial geometric uncertainty of DIR using statistical sampling techniques that can be applied to the resulting deformation vector fields (DVFs) for a given registration. The proposed DIR performance metric, the distance discordance metric (DDM), is based on the variability in the distance between corresponding voxels from different images, which are co-registered to the same voxel at location (X) in an arbitrarily chosen “reference” image. The DDM value, at location (X) in the reference image, represents the mean dispersion between voxels, when these images are registered to other images in the image set. The method requires at least four registered images to estimate the uncertainty of the DIRs, both for inter-and intra-patient DIR. To validate the proposed method, we generated an image set by deforming a software phantom with known DVFs. The registration error was computed at each voxel in the “reference” phantom and then compared to DDM, inverse consistency error (ICE), and transitivity error (TE) over the entire phantom. The DDM showed a higher Pearson correlation (Rp) with the actual error (Rp ranged from 0.6 to 0.9) in comparison with ICE and TE (Rp ranged from 0.2 to 0.8). In the resulting spatial DDM map, regions with distinct intensity gradients had a lower discordance and therefore, less variability relative to regions with uniform intensity. Subsequently, we applied DDM for intra-patient DIR in an image set of 10 longitudinal computed tomography (CT) scans of one prostate cancer patient and for inter-patient DIR in an image set of 10 planning CT scans of different head and neck cancer patients. For both intra- and inter-patient DIR, the spatial DDM map showed large variation over the volume of interest (the pelvis for the prostate patient and the head for the head and neck patients). The highest discordance was observed in the soft tissues, such as the brain, bladder, and rectum, due to higher variability in the registration. The smallest DDM values were observed in the bony structures in the pelvis and the base of the skull. The proposed metric, DDM, provides a quantitative tool to evaluate the performance of DIR when a set of images is available. Therefore, DDM can be used to estimate and visualize the uncertainty of intra- and/or inter-patient DIR based on the variability of the registration rather than the absolute registration error. PMID:24440838

Saleh, Ziad H.; Apte, Aditya P.; Sharp, Gregory C.; Shusharina, Nadezhda P.; Wang, Ya; Veeraraghavan, Harini; Thor, Maria; Muren, Ludvig P.; Rao, Shyam S.; Lee, Nancy Y.; Deasy, Joseph O.

2014-01-01

346

Radiofrequency thermal ablation with expandable needle of focal liver malignancies: complication report  

Microsoft Academic Search

The aim of this study was to describe type and rate of complications in a series of patients with liver tumors treated by the radiofrequency (RF) expandable system. A total of 166 patients, 114 with hepatocellular carcinoma (HCC; 92 small HCC, 22 large) and 52 with liver metastasis, were treated by the percutaneous RF expandable system. In large HCCs, RF

Elisabetta Buscarini; Luigi Buscarini

2004-01-01

347

Mechanisms of ischemic stroke in patients with intracranial atherosclerosis: A high-resolution magnetic resonance imaging study  

PubMed Central

High-resolution magnetic resonance imaging (HRMRI) has a unique ability to provide an evaluation of the intracranial artery wall. This study aimed to investigate the possible mechanisms of ischemic stroke in patients with intracranial atherosclerosis using HRMRI. HRMRI was performed on 55 patients (38 male and 17 female) with acute cerebral infarction to investigate the lumen-intruding plaque at the stenotic portion of the middle cerebral artery (MCA) and basilar artery (BA) and to attempt to identify the mechanisms of stroke. Penetrating artery disease (PAD) was diagnosed in 20 patients (36%) and large-artery atherosclerosis (LAA) was diagnosed in 35 patients, including 19 with parent artery plaques occluding a penetrating artery (POPA; 35%) and 16 with artery-to-artery embolisms (29%). Patients with PAD had a higher frequency of hypertension compared with that of the patients with LAA (80 versus 29%; P<0.001), and patients with LAA had a higher frequency of diabetes compared with that of the patients with PAD (40% versus 15%; P=0.054). Magnetic resonance angiography revealed mild to moderate stenosis in the patients with POPA, while border zone infarction and artery-to-artery embolism occurred in the majority of the patients with severe stenosis or occlusion of the MCA and BA. HRMRI has the ability to identify the mechanisms of intracranial atherosclerotic ischemic stroke through the detection of luminal plaques. PMID:24940449

GAO, TIANLI; YU, WEI; LIU, CHUNJIE

2014-01-01

348

Correlation of Patient Weight and Cross-Sectional Dimensions with Subjective Image Quality at Standard Dose Abdominal CT  

Microsoft Academic Search

Results: A statistically significant negative linear correlation of 0.46, 0.47, 0.47, 0.58, 0.56, 0.54, and 0.56 between patient weight, anterior abdominal fat thick- ness, anteroposterior and transverse diameter, circumference, cross-sectional area and image quality at standard scanning parameters was found (p<0.01).

Mannudeep K. Kalra; Michael M. Maher; Srinivasa R. Prasad; M. Sikandar Hayat; Michael A. Blake; Jose Varghese; Elkan F. Halpern; Sanjay Saini

2003-01-01

349

Evaluation of a Cognitive-Behavioral Intervention for Reducing Distress in Pediatric Cancer Patients Undergoing Magnetic Resonance Imaging Procedures  

Microsoft Academic Search

We evaluated efficacy of a cognitive-behavioral therapy (CBT) intervention compared to a standard care condition (SCC) in 55 pediatric patients with central nervous system cancer, aged 6 to 18 years, undergoing magnetic resonance imaging (MRI). There were no significant differences between the CBT and the SCC groups on child, parent, or staff ratings of MRI distress, child self-reports of expected

Vida L. Tyc; Laurie Leigh; Raymond K. Mulhern; Deo Kumar Srivastava; Debra Bruce

1997-01-01

350

Lethal midline granuloma: impact of imaging studies on the investigation and management of destructive mid facial disease in 13 patients  

Microsoft Academic Search

In 13 patients presenting as lethal midline granuloma (LMG), computed tomography proved essential for determining the extent of the disease, guiding biopsy and planning radiotherapy. Magnetic resonance imaging (MRI) was also helpful for the latter, because it could distinguish fluid retained within the paranasal sinuses from solid masses and tumour from granulation tissue; it was of little value for detecting

K. Marsot-Dupuch; J. Cabane; V. Raveau; N. Aoun; J. M. Tubiana

1992-01-01

351

High-precision prostate cancer irradiation by clinical application of an offline patient setup verification procedure, using portal imaging  

Microsoft Academic Search

Purpose: To investigate in three institutions, The Netherlands Cancer Institute (Antoni van Leeuwenhoek Huis [AvL]), Dr. Daniel den Hoed Cancer Center (DDHC), and Dr, Bernard Verbeeten Institute (BVI). how much the patient setup accuracy for irradiation of prostate cancer can be improved by an offline setup verification and correction procedure, using portal imaging.Methods and Materials: The verification procedure consisted of

Arjan Bel; Pieter H. Vos; Patrick T. R. Rodrigus; Carien L. Creutzberg; Andries G. Visser; Joep C. Stroom; Joos V. Lebesque

1996-01-01

352

Imagery special issue: Intrusive images and memories of earlier adverse events in patients with obsessive compulsive disorder  

Microsoft Academic Search

Mental imagery is increasingly considered to be an important feature in anxiety disorders. The aim of this study was to investigate the prevalence and characteristics of mental images in obsessive compulsive disorder (OCD) and their possible association with earlier adverse events. A consecutive sample of 37 patients with OCD admitted to a specialist unit was interviewed using a semi-structured interview.

Anne E. M. Speckens; Ann Hackmann; Anke Ehlers; Bea Cuthbert

2007-01-01

353

Optical fibre sensors embedded into technical textile for a continuous monitoring of patients under Magnetic Resonance Imaging  

Microsoft Academic Search

The potential impact of optical fiber sensors embedded into medical textiles for the continuous monitoring of the patient during Magnetic Resonance Imaging (MRI) is presented. In that way, we report on several pure optical sensing technologies for pulse oximetry and respiratory movements monitoring. The technique for pulse oximetry measurement is known as NIRS (Near Infra-Red Spectroscopy) in a reflectance mode.

J. De jonckheere; F. Narbonneau; D. Kinet; J. Zinke; B. Paquet; A. Depre; M. Jeanne; R. Logier

2008-01-01

354

Evolution of tumefactive lesions in multiple sclerosis: a 12-year study with serial imaging in a single patient.  

PubMed

We describe the acute presentation and the long-term evolution of recurrent tumefactive lesions (TLs) in a patient with relapsing-remitting multiple sclerosis. Five TLs occurred on three different occasions over a period of 12 years and these were followed by 73 serial magnetic resonance images (MRI). TL evolution was described by means of magnetization transfer imaging (MTI) and cerebrospinal fluid tissue specific imaging (TSI) over the follow-up period. During the study period, the patient had three clinical relapses with only minimal disability progression. MTI demonstrated that only the peripheral portion of each TL reverted to pre-lesional MT ratios within six months' post-enhancement. Recurring TLs may present a similar pattern of evolution that may be associated with a long-term favourable clinical outcome. PMID:24062416

Ikonomidou, Vasiliki N; Richert, Nancy D; Vortmeyer, Alexander; Tovar-Moll, Fernanda; Bielekova, Bibiana; Cook, Natalie E; Duyn, Jeff H; Bagnato, Francesca

2013-10-01

355

Quantitative cone-beam CT imaging in radiation therapy using planning CT as a prior: First patient studies  

SciTech Connect

Purpose: Quantitative cone-beam CT (CBCT) imaging is on increasing demand for high-performance image guided radiation therapy (IGRT). However, the current CBCT has poor image qualities mainly due to scatter contamination. Its current clinical application is therefore limited to patient setup based on only bony structures. To improve CBCT imaging for quantitative use, we recently proposed a correction method using planning CT (pCT) as the prior knowledge. Promising phantom results have been obtained on a tabletop CBCT system, using a correction scheme with rigid registration and without iterations. More challenges arise in clinical implementations of our method, especially because patients have large organ deformation in different scans. In this paper, we propose an improved framework to extend our method from bench to bedside by including several new components. Methods: The basic principle of our correction algorithm is to estimate the primary signals of CBCT projections via forward projection on the pCT image, and then to obtain the low-frequency errors in CBCT raw projections by subtracting the estimated primary signals and low-pass filtering. We improve the algorithm by using deformable registration to minimize the geometry difference between the pCT and the CBCT images. Since the registration performance relies on the accuracy of the CBCT image, we design an optional iterative scheme to update the CBCT image used in the registration. Large correction errors result from the mismatched objects in the pCT and the CBCT scans. Another optional step of gas pocket and couch matching is added into the framework to reduce these effects. Results: The proposed method is evaluated on four prostate patients, of which two cases are presented in detail to investigate the method performance for a large variety of patient geometry in clinical practice. The first patient has small anatomical changes from the planning to the treatment room. Our algorithm works well even without the optional iterations and the gas pocket and couch matching. The image correction on the second patient is more challenging due to the effects of gas pockets and attenuating couch. The improved framework with all new components is used to fully evaluate the correction performance. The enhanced image quality has been evaluated using mean CT number and spatial nonuniformity (SNU) error as well as contrast improvement factor. If the pCT image is considered as the ground truth, on the four patients, the overall mean CT number error is reduced from over 300 HU to below 16 HU in the selected regions of interest (ROIs), and the SNU error is suppressed from over 18% to below 2%. The average soft-tissue contrast is improved by an average factor of 2.6. Conclusions: We further improve our pCT-based CBCT correction algorithm for clinical use. Superior correction performance has been demonstrated on four patient studies. By providing quantitative CBCT images, our approach significantly increases the accuracy of advanced CBCT-based clinical applications for IGRT.

Niu Tianye; Al-Basheer, Ahmad; Zhu Lei [Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Georgia Radiation Therapy Center, Department of Radiology, Georgia Health Sciences University, Augusta, Georgia 30912 (United States); Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2012-04-15

356

Visualization of Coronary Wall Atherosclerosis in Asymptomatic Subjects and Patients with Coronary Artery Disease Using Magnetic Resonance Imaging  

PubMed Central

Background Magnetic resonance imaging (MRI) is sensitive to early atherosclerotic changes such as positive remodeling in patients with coronary artery disease (CAD). We assessed prevalence, quality, and extent of coronary atherosclerosis in a group of healthy subjects compared to patients with confirmed CAD. Methodology Twenty-two patients with confirmed CAD (15M, 7F, mean age 60.4±10.4 years) and 26 healthy subjects without history of CAD (11M, 15F, mean age 56.1±4.4 years) underwent MRI of the right coronary artery (RCA) and vessel wall (MR-CVW) on a clinical 1.5T MR-scanner. Wall thickness measurements of both groups were compared. Principal Findings Stenoses of the RCA (both < and ?50% on CAG) were present in all patients. In 21/22 patients, stenoses detected at MRI corresponded to stenoses detected with conventional angiography. In 19/26 asymptomatic subjects, there was visible luminal narrowing in the MR luminography images. Fourteen of these subjects demonstrated corresponding increase in vessel wall thickness. In 4/26 asymptomatic subjects, vessel wall thickening without luminal narrowing was present. Maximum and mean wall thicknesses in patients were significantly higher (2.16 vs 1.92 mm, and 1.38 vs 1.22 mm, both p<0.05). Conclusions In this cohort of middle-aged individuals, both patients with stable angina and angiographically proven coronary artery disease, as well as age-matched asymptomatic subjects. exhibited coronary vessel wall thickening detectable with MR coronary vessel wall imaging. Maximum and mean wall thicknesses were significantly higher in patients. The vast majority of asymptomatic subjects had either positive remodeling without luminal narrowing, or non-significant stenosis. Trial registration ClinicalTrials.gov NCT00456950 PMID:20927368

Gerretsen, Suzanne C.; Kooi, M. Eline; Kessels, Alfons G.; Schalla, Simon; Katoh, Marcus; van der Geest, Rob J.; Manning, Warren J.; Waltenberger, Johannes; van Engelshoven, Jos M. A.; Botnar, Rene M.; Leiner, Tim

2010-01-01

357

Body image in idiopathic scoliosis: a comparison study of psychometric properties between four patient-reported outcome instruments  

PubMed Central

Background Four patient-reported outcome (PRO) instruments are commonly used to assess body image in idiopathic scoliosis (IS): the Quality of Life Profile for Spinal Deformities (QLPSD), SRS-22 Self-Image scale, Spinal Appearance Questionnaire (SAQ), and Trunk Appearance Perception Scale (TAPS). The aim of this study is to compare the psychometric properties of these instruments in patients with IS and report the translational/cultural adaptation of the SAQ to Spanish. Methods The four instruments in a Spanish version were administered to 80 patients with IS aged 10 to 40 years old. The sample was stratified according to scoliosis magnitude (less and more than 45º). Analysis was also conducted for age groups. The psychometric properties studied included convergent and divergent construct validity, as well as internal consistency. Convergent validity was evaluated by correlation analysis between the self-image instruments and Cobb angle. Divergent validity was assessed with correlation analysis between PRO scores and SRS-22 dimensions scores such as Function, Pain and Mental Health. Results In the overall sample, each of the PRO instruments demonstrated high internal consistency (QLPSD Body Image, ??=?0.80; SRS-22 Self Image, ??=?0.78; SAQ, ??=?0.89; TAPS, ??=?0.87), also both for younger and adult patients subgroups. Correlation with curve magnitude was significant for each of the four scales. However, the correlation was higher for the pictorial scales (SAQ Appearance r?=?0.61, TAPS r?=?- 0.62) than for the textual scales (QLPSD-bi r?=?0.36, SRS-22 Self-Image scale r?=?- 0.41). In the younger group, correlation between Cobb angle and textual scales (QLPSD-bi and SRS-22 Self-Image Scale) was not significant. Body Image scales showed significant correlations with SRS-22 Pain, Function and Mental Health dimensions. Conclusions All four instruments tested have good psychometric properties. Pictorial scales (SAQ Appearance and TAPS) correlated better with the radiological magnitude of the curve and this correlation is independent of age. Unexpectedly, all four scales demonstrated significant correlations with non-body image dimensions and the divergent hypothesis was not confirmed. Globally, pictorial scales showed slightly better construct validity to test body image perception than textual scales. PMID:24894714

2014-01-01

358

When does Subliminal Affective Image Priming Influence the Ability of Schizophrenic Patients to Perceive Face Emotions?  

PubMed Central

Background Deficits in face emotion perception are among the most pervasive aspects of schizophrenia impairments which strongly affects interpersonal communication and social skills. Material/Methods Schizophrenic patients (PSZ) and healthy control subjects (HCS) performed 2 psychophysical tasks. One, the SAFFIMAP test, was designed to determine the impact of subliminally presented affective or neutral images on the accuracy of face-expression (angry or neutral) perception. In the second test, FEP, subjects saw pictures of face-expression and were asked to rate them as angry, happy, or neutral. The following clinical scales were used to determine the acute symptoms in PSZ: Positive and Negative Syndrome (PANSS), Young Mania Rating (YMRS), Hamilton Depression (HAM-D), and Hamilton Anxiety (HAM-A). Results On the SAFFIMAP test, different from the HCS group, the PSZ group tended to categorize the neutral expression of test faces as angry and their response to the test-face expression was not influenced by the affective content of the primes. In PSZ, the PANSS-positive score was significantly correlated with correct perception of angry faces for aggressive or pleasant primes. YMRS scores were strongly correlated with PSZ’s tendency to recognize angry face expressions when the prime was a pleasant or a neutral image. The HAM-D score was positively correlated with categorizing the test-faces as neutral, regardless of the affective content of the prime or of the test-face expression (angry or neutral). Conclusions Despite its exploratory nature, this study provides the first evidence that conscious perception and categorization of facial emotions (neutral or angry) in PSZ is directly affected by their positive or negative symptoms of the disease as defined by their individual scores on the clinical diagnostic scales. PMID:25537115

Vaina, Lucia M.; Rana, Kunjan D.; Cotos, Ionela; Li-Yang, Chen; Huang, Melissa A.; Podea, Delia

2014-01-01

359

When does Subliminal Affective Image Priming Influence the Ability of Schizophrenic Patients to Perceive Face Emotions?  

PubMed

Background Deficits in face emotion perception are among the most pervasive aspects of schizophrenia impairments which strongly affects interpersonal communication and social skills. Material and Methods Schizophrenic patients (PSZ) and healthy control subjects (HCS) performed 2 psychophysical tasks. One, the SAFFIMAP test, was designed to determine the impact of subliminally presented affective or neutral images on the accuracy of face-expression (angry or neutral) perception. In the second test, FEP, subjects saw pictures of face-expression and were asked to rate them as angry, happy, or neutral. The following clinical scales were used to determine the acute symptoms in PSZ: Positive and Negative Syndrome (PANSS), Young Mania Rating (YMRS), Hamilton Depression (HAM-D), and Hamilton Anxiety (HAM-A). Results On the SAFFIMAP test, different from the HCS group, the PSZ group tended to categorize the neutral expression of test faces as angry and their response to the test-face expression was not influenced by the affective content of the primes. In PSZ, the PANSS-positive score was significantly correlated with correct perception of angry faces for aggressive or pleasant primes. YMRS scores were strongly correlated with PSZ's tendency to recognize angry face expressions when the prime was a pleasant or a neutral image. The HAM-D score was positively correlated with categorizing the test-faces as neutral, regardless of the affective content of the prime or of the test-face expression (angry or neutral). Conclusions Despite its exploratory nature, this study provides the first evidence that conscious perception and categorization of facial emotions (neutral or angry) in PSZ is directly affected by their positive or negative symptoms of the disease as defined by their individual scores on the clinical diagnostic scales. PMID:25537115

Vaina, Lucia Maria; Rana, Kunjan D; Cotos, Ionela; Li-Yang, Chen; Huang, Melissa A; Podea, Delia

2014-01-01

360

Automatic detection and segmentation of ischemic lesions in computed tomography images of stroke patients  

NASA Astrophysics Data System (ADS)

Stroke is the third most common cause of death in developed countries. Clinical trials are currently investigating whether advanced Computed Tomography can be of benefit for diagnosing stroke at the acute phase. These trials are based on large patients cohorts that need to be manually annotated to obtain a reference standard of tissue loss at follow-up, resulting in extensive workload for the radiologists. Therefore, there is a demand for accurate and reliable automatic lesion segmentation methods. This paper presents a novel method for the automatic detection and segmentation of ischemic lesions in CT images. The method consists of multiple sequential stages. In the initial stage, pixel classification is performed using a naive Bayes classifier in combination with a tissue homogeneity algorithm in order to localize ischemic lesion candidates. In the next stage, the candidates are segmented using a marching cubes algorithm. Regional statistical analysis is used to extract features based on local information as well as contextual information from the contra-lateral hemisphere. Finally, the extracted features are summarized into a likelihood of ischemia by a supervised classifier. An area under the Receiver Operating Characteristic curve of 0.91 was obtained for the identification of ischemic lesions. The method performance on lesion segmentation reached a Dice similarity coeficient (DSC) of 0.74+/-0.09, whereas an independent human observer obtained a DSC of 0.79+/-0.11 in the same dataset. The experiments showed that it is feasible to automatically detect and segment ischemic lesions in CT images, obtaining a comparable performance as human observers.

Vos, Pieter C.; Biesbroek, J. Matthijs; Weaver, Nick A.; Velthuis, Birgitta K.; Viergever, Max A.

2013-03-01

361

A patient specific 4D MRI liver motion model based on sparse imaging and registration  

NASA Astrophysics Data System (ADS)

Introduction: Image-guided minimally invasive procedures are becoming increasingly popular. Currently, High-Intensity Focused Ultrasound (HIFU) treatment of lesions in mobile organs, such as the liver, is in development. A requirement for such treatment is automatic motion tracking, such that the position of the lesion can be followed in real time. We propose a 4D liver motion model, which can be used during planning of this procedure. During treatment, the model can serve as a motion predictor. In a similar fashion, this model could be used for radiotherapy treatment of the liver. Method: The model is built by acquiring 2D dynamic sagittal MRI data at six locations in the liver. By registering these dynamics to a 3D MRI liver image, 2D deformation fields are obtained at every location. The 2D fields are ordered according to the position of the liver at that specific time point, such that liver motion during an average breathing period can be simulated. This way, a sparse deformation field is created over time. This deformation field is finally interpolated over the entire volume, yielding a 4D motion model. Results: The accuracy of the model is evaluated by comparing unseen slices to the slice predicted by the model at that specific location and phase in the breathing cycle. The mean Dice coefficient of the liver regions was 0.90. The mean misalignment of the vessels was 1.9 mm. Conclusion: The model is able to predict patient specific deformations of the liver and can predict regular motion accurately.

Noorda, Y. H.; Bartels, L. W.; van Stralen, Marijn; Pluim, J. P. W.

2013-03-01

362

Lymph node shape in computed tomography imaging as a predictor for axillary lymph node metastasis in patients with breast cancer  

PubMed Central

The aim of the present study was to evaluate whether preoperative computed tomography (CT) is a useful modality for the diagnosis of axillary lymph node metastasis. The axillary lymph node status was examined in patients with primary breast cancer who had undergone surgery. In total, 75 patients were analyzed with preoperative contrast CT images, following which the patients underwent an intraoperative sentinel lymph node biopsy to determine possible predictors of axillary lymph node metastasis. The lymph node shape was classified into three groups, which included fat-, clear-and obscure-types. Multivariate analysis revealed that clear-type lymph nodes in preoperative contrast CT imaging may be an independent predictor of lymph node metastasis (odds ratio, 15; P=0.003). Therefore, the results indicated that preoperative CT examination is useful to predict axillary lymph node metastasis. PMID:25009640

KUTOMI, GORO; OHMURA, TOUSEI; SATOMI, FUKINO; TAKAMARU, TOMOKO; SHIMA, HIROAKI; SUZUKI, YASUYO; OTOKOZAWA, SEIKO; ZEMBUTSU, HITOSHI; MORI, MITSURU; HIRATA, KOICHI

2014-01-01

363

Medical image analysis of electron micrographs in diabetic patients using contrast enhancement  

Microsoft Academic Search

Today, there is almost no area of technical endeavor that is not impacted in some way or the other by digital image processing. The principle objective of enhancement is to process an image so that the result is more suitable than original image for specific application. When an image is processed for visual interpretation, the viewer is the ultimate judge

F. Shaik; M. N. Giri Prasad; J. Rao; B. Abdul Rahim; A. SomaSekhar

2010-01-01

364

Expanded Plain TEX Steven Smith  

E-print Network

Expanded Plain TEX Sept 2004 2.8.4 Karl Berry Steven Smith #12;This manual documents the Eplain Berry. Steven Smith wrote the documentation for the commutative diagram macros. (He also wrote the macros.) Some additions/corrections by Adam Lewenberg. Permission is granted to make and distribute

Mintmire, John W.

365

Expanding the eukaryotic genetic code  

SciTech Connect

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Chin, Jason W. (Cambridge, GB); Cropp, T. Ashton (Bethesda, MD); Anderson, J. Christopher (San Francisco, CA); Schultz, Peter G. (La Jolla, CA)

2009-12-01

366

Expanding the eukaryotic genetic code  

DOEpatents

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Chin, Jason W. (Cambridge, GB); Cropp, T. Ashton (Bethesda, MD); Anderson, J. Christopher (San Francisco, CA); Schultz, Peter G. (La Jolla, CA)

2010-09-14

367

Expanding the eukaryotic genetic code  

SciTech Connect

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Chin, Jason W. (Cambridge, GB); Cropp, T. Ashton (Bethesda, MD); Anderson, J. Christopher (San Francisco, CA); Schultz, Peter G. (La Jolla, CA)

2009-11-17

368

Expanding the eukaryotic genetic code  

SciTech Connect

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Chin, Jason W. (Cambridge, GB); Cropp, T. Ashton (Bethesda, MD); Anderson, J. Christopher (San Francisco, CA); Schultz, Peter G. (La Jolla, CA)

2009-10-27

369

The Expanding Frontier of Pluralism.  

ERIC Educational Resources Information Center

Looks at the expanding frontier of pluralism in terms of reappraising the relationship of formal education to the advent of the constant change (occupational and social) accelerated by the microprocessor revolution and readjusting provisions in educational systems to meet the different needs of different populations. (AH)

King, Edmund

1983-01-01

370

Expanding the Trilinos developer community  

Microsoft Academic Search

The Trilinos Project started approximately nine years ago as a small effort to enable research, development and ongoing support of small, related solver software efforts. The 'Tri' in Trilinos was intended to indicate the eventual three packages we planned to develop. In 2007 the project expanded its scope to include any package that was an enabling technology for technical computing.

Heroux; Michael Allen

2010-01-01

371

Expanding the eukaryotic genetic code  

DOEpatents

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Chin, Jason W.; Cropp, T. Ashton; Anderson, J. Christopher; Schultz, Peter G.

2013-01-22

372

Expanding the eukaryotic genetic code  

DOEpatents

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Chin, Jason W. (Cambridge, GB); Cropp, T. Ashton (Bethesda, MD); Anderson, J. Christopher (San Francisco, CA); Schultz, Peter G. (La Jolla, CA)

2012-02-14

373

Expanding the eukaryotic genetic code  

DOEpatents

This invention provides compositions and methods for producing translational components that expand the number of genetically encoded amino acids in eukaryotic cells. The components include orthogonal tRNAs, orthogonal aminoacyl-tRNA synthetases, orthogonal pairs of tRNAs/synthetases and unnatural amino acids. Proteins and methods of producing proteins with unnatural amino acids in eukaryotic cells are also provided.

Chin, Jason W. (Cambridge, GB); Cropp, T. Ashton (Bethesda, MD); Anderson, J. Christopher (San Francisco, CA); Schultz, Peter G. (La Jolla, CA)

2012-05-08

374

Teleteach Expanded Delivery System: Evaluation.  

ERIC Educational Resources Information Center

In order to meet the demand for Air Force Institute of Technology (AFIT) professional continuing education (PCE) courses within the School of Systems and Logistics and the School of Engineering, the Teleteach Expanded Delivery System (TEDS) for instruction of Air Force personnel at remote locations was developed and evaluated. TEDS uses a device…

Christopher, G. Ronald; Milam, Alvin L.

375

Paul Hanna and "Expanding Communities"  

ERIC Educational Resources Information Center

The development and promotion of the "expanding communities" curriculum design model for teaching elementary school social studies was a crucial episode in the history of social studies. This article profiles how the model developed in the mind of its most effective promoter, Paul Robert Hanna. Paul Hanna understood early in his career the…

Stallones, Jared R.

2004-01-01

376

Common Ground: Expanding Our Horizons.  

ERIC Educational Resources Information Center

In "Common Ground: Dialogue, Understanding, and the Teaching of Composition," Kurt Spellmeyer seeks to familiarize students and teachers with the linguistic and cultural no-man's-land separating them. Reinstating the value of two writing conventions often used by traditional students--expressive and commonplaces--can help expand on the horizons of…

McDevitt, Michele J.

377