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1

Tissue Expander versus Tissue Expander and Latissimus Flap in Morbidly Obese Breast Reconstruction Patients  

PubMed Central

Background: Immediate postmastectomy breast reconstruction in morbidly obese patients represents a challenge because neither prosthetic nor abdominal-based options may be suitable. Methods: This study compared a previously published cohort of immediate prosthetic reconstruction of 346 patients (511 breasts) of whom 49 patients (67 breasts) were morbidly obese (defined as a body mass index > 35) with a morbidly obese patient population whose breasts were reconstructed immediately following postmastectomy with latissimus flap and tissue expander (21 patients and 22 breasts) in the same time period. The preoperative risk factors of mastectomy such as tobacco use, diabetes, and prior radiation and the postoperative complications of mastectomy such as skin necrosis, seroma, and prosthesis loss were examined. The explantation of the tissue expander provided a defined endpoint of reconstruction failure. Results: The average body mass index in the tissue expander/implant group and in the latissimus flap plus tissue expander/implant group was 40.9 and 40.1, respectively. The risk profile of diabetes and tobacco use was similar in both groups. Fifteen of the 67 breasts (22.3%) of the tissue expander/implant group and 15 of the 23 breasts (65.2%) of the latissimus flap group had received prior radiation. The prosthesis loss was 13 of 67 breasts (19.4%) that had tissue-expander–alone reconstruction and 1 of 22 (4.8%) in the latissimus group that had tissue expander reconstruction. Modification of donor-site incision and skin-island location in the latissimus group of patients can minimize scar deformity. Conclusion: The loss rate in immediate postmastectomy reconstruction in morbidly obese patients with latissimus flap plus tissue expander was substantially lower than the loss rate in those with breast reconstructed with tissue expander alone.

Adams, Robert L.; Chandler, Robert G.; Parks, Joseph

2015-01-01

2

Expanding Perspectives for Comprehending Visual Images in Multimodal Texts  

ERIC Educational Resources Information Center

The texts that adolescents encounter today are often multimodal, meaning they incorporate a variety of modes, including visual images, hypertext, and graphic design elements along with written text. Expanding the perspectives readers use to make sense of the multimodal texts is an important aspect of comprehension instruction. Moving beyond the…

Serafini, Frank

2011-01-01

3

Beyond Patient Health Escalating populations, expanding urban environments, poverty,  

E-print Network

Beyond Patient Health Escalating populations, expanding urban environments, poverty, pollution fellowships and an endowed Chair in Ecosystem Health · The Department of Biology offers undergraduates a Major health · The Chair also leads the development of the ecosystem health curriculum in the Faculty

Denham, Graham

4

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

5

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 collimator 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. 13 figs.

Jannson, T.; Jannson, J.; Yeung, P.

1990-02-06

6

Nanoscale imaging reveals laterally expanding antimicrobial pores in lipid bilayers  

PubMed Central

Antimicrobial peptides are postulated to disrupt microbial phospholipid membranes. The prevailing molecular model is based on the formation of stable or transient pores although the direct observation of the fundamental processes is lacking. By combining rational peptide design with topographical (atomic force microscopy) and chemical (nanoscale secondary ion mass spectrometry) imaging on the same samples, we show that pores formed by antimicrobial peptides in supported lipid bilayers are not necessarily limited to a particular diameter, nor they are transient, but can expand laterally at the nano-to-micrometer scale to the point of complete membrane disintegration. The results offer a mechanistic basis for membrane poration as a generic physicochemical process of cooperative and continuous peptide recruitment in the available phospholipid matrix. PMID:23671080

Rakowska, Paulina D.; Jiang, Haibo; Ray, Santanu; Pyne, Alice; Lamarre, Baptiste; Carr, Matthew; Judge, Peter J.; Ravi, Jascindra; M. Gerling, Ulla I.; Koksch, Beate; Martyna, Glenn J.; Hoogenboom, Bart W.; Watts, Anthony; Crain, Jason; Grovenor, Chris R. M.; Ryadnov, Maxim G.

2013-01-01

7

Complications and patient satisfaction following expander\\/implant breast reconstruction with and without radiotherapy  

Microsoft Academic Search

Purpose: To compare the rates of complications and patient satisfaction among breast cancer patients treated with mastectomy and tissue expander\\/implant reconstruction with and without radiotherapy.Methods and Materials: As part of the Michigan Breast Reconstruction Outcome Study (MBROS), breast cancer patients undergoing mastectomy with reconstruction were prospectively evaluated with respect to complications, general patient satisfaction with reconstruction, and esthetic satisfaction. Included

Editha A Krueger; Edwin G Wilkins; Myla Strawderman; Paul Cederna; Sherry Goldfarb; Frank A Vicini; Lori J Pierce

2001-01-01

8

Osteoma of long bone: an expanding spectrum of imaging findings.  

PubMed

Osteoma of long bone is an extremely rare, benign bone-forming surface lesion with the largest published case series consisting of only 14 patients. The most important and often most difficult lesion to differentiate from osteoma of long bone radiographically is parosteal osteosarcoma, which is a rare, low-grade surface osteosarcoma with the potential for dedifferentiation. Reports of imaging studies of osteoma of long bone depict a well-defined ossified mass arising from the surface of the diaphysis or metadiaphysis of a long bone. A characteristic feature is the homogeneity of the mass, with uniform density near or equal to that of cortical bone from the base of the lesion to its periphery. The 45-year-old female in this case presented with left hip fullness and was subsequently found to have a proximal femoral osteoma, which was unique in that it contained large fatty marrow spaces that corresponded to bands of relatively low density on plain radiography and computed tomography, giving it a heterogeneous appearance atypical of osteoma of long bone. Furthermore, the osteoma reported here was associated with a small but separate nodular focus of ossification in the adjacent soft tissue. These findings led to a presumptive diagnosis of parosteal osteosarcoma with a local soft tissue metastasis or satellite nodule resulting in radical resection of the tumor. Definitive diagnosis of osteoma was made on histology of both the parent lesion and ossified nodule as no neoplastic spindle cell proliferation was present to establish a diagnosis of low-grade osteosarcoma. This represents, to the best of our knowledge, the first such presentation of osteoma of long bone. PMID:25380570

Hansford, Barry Glenn; Pytel, Peter; Moore, Drew D; Stacy, Gregory Scott

2015-05-01

9

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.

10

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

11

Sacrococcygeal chordoma: MR imaging in 30 patients  

Microsoft Academic Search

ObjectiveTo evaluate MR imaging of sacrococcygeal chordoma.Design and patientsThirty patients (age range 22–80 years) underwent MR imaging for the diagnosis and preoperative evaluation of sacrococcygeal chordomas. Eight patients had follow-up MR examination after treatment. The MR images were performed with T1- and T2-weighted imaging, and gadolinium (Gd)-enhanced imaging. The MR images were analyzed for the signal intensity, enhancing pattern, tumor size,

Mi Sook Sung; Gyung Kyu Lee; Heung Sik Kang; Soon Tae Kwon; Jin Gyoon Park; Jin Suk Suh; Gil Ho Cho; Sung Moon Lee; Myung Hee Chung; Donald Resnick

2005-01-01

12

Is the Vertebral Expandable Prosthetic Titanium Rib a Surgical Alternative in Patients with Spina Bifida?  

Microsoft Academic Search

Background  Nonambulatory children with myelodysplasia are most likely to develop spinal deformity. As the deformity progresses, the overall\\u000a health of the patient deteriorates. Traditional management of the deformity with fusion results in a short trunk, crankshaft\\u000a deformity, and spine and lung growth inhibition. One alternative that potentially minimizes these problems is the vertebral\\u000a expandable prosthetic titanium rib (VEPTR).\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We therefore asked

John M. Flynn; Norman Ramirez; John B. Emans; John T. Smith; Mary Jane Mulcahey; Randal R. Betz

2011-01-01

13

The Precision Expandable Radar Calibration Sphere (PERCS) With Applications for Laser Imaging and Ranging  

NASA Astrophysics Data System (ADS)

The Naval Research Laboratory will provide an orbiting calibration sphere to be used with ground-based laser imaging telescopes and HF radio systems. The Precision Expandable Radar Calibration Sphere (PERCS) is a practical, reliable, high-performance HF calibration sphere and laser imaging target to orbit at about 600 km altitude. The sphere will be made of a spherical wire frame with aspect independent radar cross section in the 3 to 35 MHz frequency range. The necessary launch vehicle to place the PERCS in orbit will be provided by the Department of Defense Space Test Program. The expandable calibration target has a stowed diameter of 1 meter and a fully deployed diameter of 10.2 meters. A separate deployment mechanism is provided for the sphere. After deployment, the Precision Expandable Radar Calibration Sphere (PERCS) with 180 vertices will be in a high inclination orbit to scatter radio pulses from a number of ground systems, including (1) over-the-horizon (OTH) radars operated by the United States and Australia; (2) high power HF facilities such as HAARP in Alaska, EISCAT in Norway, and Arecibo in Puerto Rico; (3) the chain of high latitude SuperDARN radars used for auroral region mapping; and (4) HF direction finding for Navy ships. With the PERCS satellite, the accuracy of HF radars can be periodically checked for range, elevation, and azimuth errors. In addition, each of the 360 vertices on the PERCS sphere will support an optical retro-reflector for operations with ground laser facilities used to track satellites. The ground laser systems will be used to measure the precise location of the sphere within one cm accuracy and will provide the spatial orientation of the sphere as well as the rotation rate. The Department of Defense facilities that can use the corner-cube reflectors on the PERCS include (1) the Air Force Maui Optical Site (AMOS), (2) the Starfire Optical Range (SOR), and (3) the NRL Optical Test Facility (OTF).

Bernhardt, P.; Nicholas, A.; Thomas, L.; Davis, M.; Hoberman, C.; Davis, M.

14

Clonally expanded plasma cells in the cerebrospinal fluid of MS patients produce myelin-specific antibodies.  

PubMed

Clonally expanded plasma cells (cePC) and their presumed products, oligoclonal immunoglobulin G bands (OCB), are characteristic findings in the cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS). While cePC and OCB strongly suggest an involvement of B cell-dependent immune mechanisms in the pathogenesis of MS, their actual pathological relevance and target antigens remain unknown. To further understand the potential role played by cePC, we generated a panel of monoclonal antibodies (MS-mAb) from CSF-derived cePC from four patients with early or definite MS. Single-cell RT-PCR of correctly paired heavy and light chain immunoglobulin genes from individual cePC ensured the subsequent resurrection of their original antigen specificity. Immunofluorescence stainings of MS lesion tissue with MS-mAb revealed myelin reactivity in the cePC repertoire of all four patients and intracellular filament reactivity in one patient. While myelin staining by MS-mAb was only rarely detectable in non-MS CNS white matter tissue, it was greatly enhanced at the edge of demyelinating lesions in MS brain tissue. Our findings provide conclusive evidence for the presence of an antigen-driven B cell response in the CSF of MS patients directed against epitopes present in areas of myelin degradation. PMID:18521957

von Büdingen, Hans-Christian; Harrer, Melanie D; Kuenzle, Sandra; Meier, Mirjam; Goebels, Norbert

2008-07-01

15

JAMA Patient Page: Magnetic Resonance Imaging  

MedlinePLUS

... of the American Medical Association JAMA PATIENT PAGE Magnetic Resonance Imaging M agnetic resonance imaging (MRI) uses magnetic fields ... of magnetic fields processed with highly sophisticated computers, MRI scans produce detailed and clear pictures of body parts. ...

16

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

17

Frequent occurrence of highly expanded but unrelated B-cell clones in patients with multiple myeloma.  

PubMed

Clonal diversity in multiple myeloma (MM) includes both MM-related and MM-unrelated clonal expansions which are subject to dominance exerted by the MM clone. Here we show evidence for the existence of minor but highly expanded unrelated B-cell clones in patients with MM defined by their complementary determining region 3 (CDR3) peak. We further characterize these clones over the disease and subsequent treatment. Second clones were identified by their specific IgH-VDJ sequences that are distinct from those of dominant MM clones. Clonal frequencies were determined through semi-quantitative PCR, quantitative PCR and single-cell polymerase chain reaction of the clone-specific sequence. In 13/74 MM patients, more than one dominant CDR3 peak was identified with 12 patients (16%) being truly biclonal. Second clones had different frequencies, were found in different locations and were found in different cell types from the dominant MM clone. Where analysis was possible, they were shown to have chromosomal characteristic distinct from those of the MM clone. The frequency of the second clone also changed over the course of the disease and often persisted despite treatment. Molecularly-defined second clones are infrequent in monoclonal gammopathy of undetermined significance (MGUS, 1/43 individuals or 2%), suggesting that they may arise at relatively late stages of myelomagenesis. In further support of our findings, biclonal gammopathy and concomitant MM and CLL (chronic lymphocytic leukemia) were confirmed to originate from two unrelated clones. Our data supports the idea that the clone giving rise to symptomatic myeloma exerts clonal dominance to prevent expansion of other clones. MM and second clones may arise from an underlying niche permissive of clonal expansion. The clinical significance of these highly expanded but unrelated clones remains to be confirmed. Overall, our findings add new dimensions to evaluating related and unrelated clonal expansions in MM and the impact of disease evolution and treatment on clonal diversity. PMID:23724106

Kriangkum, Jitra; Motz, Sarah N; Debes Marun, Carina S; Lafarge, Sandrine T; Gibson, Spencer B; Venner, Christopher P; Johnston, James B; Belch, Andrew R; Pilarski, Linda M

2013-01-01

18

Frequent Occurrence of Highly Expanded but Unrelated B-Cell Clones in Patients with Multiple Myeloma  

PubMed Central

Clonal diversity in multiple myeloma (MM) includes both MM-related and MM-unrelated clonal expansions which are subject to dominance exerted by the MM clone. Here we show evidence for the existence of minor but highly expanded unrelated B-cell clones in patients with MM defined by their complementary determining region 3 (CDR3) peak. We further characterize these clones over the disease and subsequent treatment. Second clones were identified by their specific IgH-VDJ sequences that are distinct from those of dominant MM clones. Clonal frequencies were determined through semi-quantitative PCR, quantitative PCR and single-cell polymerase chain reaction of the clone-specific sequence. In 13/74 MM patients, more than one dominant CDR3 peak was identified with 12 patients (16%) being truly biclonal. Second clones had different frequencies, were found in different locations and were found in different cell types from the dominant MM clone. Where analysis was possible, they were shown to have chromosomal characteristic distinct from those of the MM clone. The frequency of the second clone also changed over the course of the disease and often persisted despite treatment. Molecularly-defined second clones are infrequent in monoclonal gammopathy of undetermined significance (MGUS, 1/43 individuals or 2%), suggesting that they may arise at relatively late stages of myelomagenesis. In further support of our findings, biclonal gammopathy and concomitant MM and CLL (chronic lymphocytic leukemia) were confirmed to originate from two unrelated clones. Our data supports the idea that the clone giving rise to symptomatic myeloma exerts clonal dominance to prevent expansion of other clones. MM and second clones may arise from an underlying niche permissive of clonal expansion. The clinical significance of these highly expanded but unrelated clones remains to be confirmed. Overall, our findings add new dimensions to evaluating related and unrelated clonal expansions in MM and the impact of disease evolution and treatment on clonal diversity. PMID:23724106

Kriangkum, Jitra; Motz, Sarah N.; Debes Marun, Carina S.; Lafarge, Sandrine T.; Gibson, Spencer B.; Venner, Christopher P.; Johnston, James B.; Belch, Andrew R.; Pilarski, Linda M.

2013-01-01

19

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

20

Expanding Imaging Capabilities for Microfluidics: Applicability of Darkfield Internal Reflection Illumination (DIRI) to Observations in Microfluidics  

PubMed Central

Microfluidics is used increasingly for engineering and biomedical applications due to recent advances in microfabrication technologies. Visualization of bubbles, tracer particles, and cells in a microfluidic device is important for designing a device and analyzing results. However, with conventional methods, it is difficult to observe the channel geometry and such particles simultaneously. To overcome this limitation, we developed a Darkfield Internal Reflection Illumination (DIRI) system that improved the drawbacks of a conventional darkfield illuminator. This study was performed to investigate its utility in the field of microfluidics. The results showed that the developed system could clearly visualize both microbubbles and the channel wall by utilizing brightfield and DIRI illumination simultaneously. The methodology is useful not only for static phenomena, such as clogging, but also for dynamic phenomena, such as the detection of bubbles flowing in a channel. The system was also applied to simultaneous fluorescence and DIRI imaging. Fluorescent tracer beads and channel walls were observed clearly, which may be an advantage for future microparticle image velocimetry (?PIV) analysis, especially near a wall. Two types of cell stained with different colors, and the channel wall, can be recognized using the combined confocal and DIRI system. Whole-slide imaging was also conducted successfully using this system. The tiling function significantly expands the observing area of microfluidics. The developed system will be useful for a wide variety of engineering and biomedical applications for the growing field of microfluidics. PMID:25748425

Kawano, Yoshihiro; Otsuka, Chino; Sanzo, James; Higgins, Christopher; Nirei, Tatsuo; Schilling, Tobias; Ishikawa, Takuji

2015-01-01

21

Expanding Imaging Capabilities for Microfluidics: Applicability of Darkfield Internal Reflection Illumination (DIRI) to Observations in Microfluidics.  

PubMed

Microfluidics is used increasingly for engineering and biomedical applications due to recent advances in microfabrication technologies. Visualization of bubbles, tracer particles, and cells in a microfluidic device is important for designing a device and analyzing results. However, with conventional methods, it is difficult to observe the channel geometry and such particles simultaneously. To overcome this limitation, we developed a Darkfield Internal Reflection Illumination (DIRI) system that improved the drawbacks of a conventional darkfield illuminator. This study was performed to investigate its utility in the field of microfluidics. The results showed that the developed system could clearly visualize both microbubbles and the channel wall by utilizing brightfield and DIRI illumination simultaneously. The methodology is useful not only for static phenomena, such as clogging, but also for dynamic phenomena, such as the detection of bubbles flowing in a channel. The system was also applied to simultaneous fluorescence and DIRI imaging. Fluorescent tracer beads and channel walls were observed clearly, which may be an advantage for future microparticle image velocimetry (?PIV) analysis, especially near a wall. Two types of cell stained with different colors, and the channel wall, can be recognized using the combined confocal and DIRI system. Whole-slide imaging was also conducted successfully using this system. The tiling function significantly expands the observing area of microfluidics. The developed system will be useful for a wide variety of engineering and biomedical applications for the growing field of microfluidics. PMID:25748425

Kawano, Yoshihiro; Otsuka, Chino; Sanzo, James; Higgins, Christopher; Nirei, Tatsuo; Schilling, Tobias; Ishikawa, Takuji

2015-01-01

22

Aneurysmal lesions of patients with abdominal aortic aneurysm contain clonally expanded T cells.  

PubMed

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; Platsoucas, Chris D

2014-05-15

23

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

24

Finding of a clinical trial on symptoms and patients satisfaction under surgery with tissue expander with external port  

PubMed Central

Background: Tissue expanders are devices which are used to create enough skin to form suitable flap in restoration of great skin deficiencies which are not modified initially. The current study aimed at investigating the patients’ satisfaction and the complications such as rupture, hematoma, wound infection, seroma, leakage, chronic pain, and expander expose of internal (implanted under the skin) and external (implanted outside) ports. Materials and Methods: In a prospective quasiexperimental study conducted at Alzahra and Imam Musa al-Kadhim educational referral hospitals in Isfahan, two matched groups of patients each one contained 38 patients undergone, external and internal ports, were followed-up weekly until the removal of expander and the injection was done weekly through port. The frequency of complications and patients’ satisfaction between two groups were compared. Results: The of age for patients in internal and external groups were 25.5 ± 8.7 and 24.7 ± 9, respectively (P = 0.71). There was significant difference between average of operation time of internal and external group (97.3 vs. 79.6; P < 0.001). The rate of complications such as infection, hematoma, skin necrosis, and expander expose between two groups was comparable, while significant difference was found between groups in terms of pain intensity in injection [4.92(1.2) vs. 1.53(0.69), P < 0.001]. There was no significant difference between groups in terms of symptom incidence and tissue expander insertion place as well as patients’ satisfaction. Conclusion: Although internal port has favorite appearance; however, some complications such as skin infection due to frequent injection, pain rate are higher than external port lead to its more acceptability by the patients.

Abdali, Hosein; Hadilou, Mansour

2015-01-01

25

Development of a bent Laue beam-expanding double-crystal monochromator for biomedical X-ray imaging  

PubMed Central

The Biomedical Imaging and Therapy (BMIT) beamline at the Canadian Light Source has produced some excellent biological imaging data. However, the disadvantage of a small vertical beam limits its usability in some applications. Micro-computed tomography (micro-CT) imaging requires multiple scans to produce a full projection, and certain dynamic imaging experiments are not possible. A larger vertical beam is desirable. It was cost-prohibitive to build a longer beamline that would have produced a large vertical beam. Instead, it was proposed to develop a beam expander that would create a beam appearing to originate at a source much farther away. This was accomplished using a bent Laue double-crystal monochromator in a non-dispersive divergent geometry. The design and implementation of this beam expander is presented along with results from the micro-CT and dynamic imaging tests conducted with this beam. Flux (photons per unit area per unit time) has been measured and found to be comparable with the existing flat Bragg double-crystal monochromator in use at BMIT. This increase in overall photon count is due to the enhanced bandwidth of the bent Laue configuration. Whilst the expanded beam quality is suitable for dynamic imaging and micro-CT, further work is required to improve its phase and coherence properties. PMID:24763635

Martinson, Mercedes; Samadi, Nazanin; Belev, George; Bassey, Bassey; Lewis, Rob; Aulakh, Gurpreet; Chapman, Dean

2014-01-01

26

Imaging of trauma in the pregnant patient.  

PubMed

The pregnant trauma patient presents an important and challenging encounter for the clinical team and radiologist. In this article, we present several key aspects of the imaging workup of pregnant trauma patients, beginning with a review of the modalities that are used in this setting. Ultrasonography plays an important role in initial evaluation of the fetus but a limited role in evaluation of maternal injuries. Given that conventional radiography and computed tomography are the "workhorse" modalities for evaluation of pregnant trauma patients, radiologists must pay particular attention to radiation dose concerns. Magnetic resonance imaging can be used after the initial evaluation and for follow-up imaging, and safety concerns related to its use in pregnant patients are addressed. At imaging interpretation, radiologists must contend not only with the typical spectrum of injuries that can be seen in any trauma patient but also with pregnancy-specific injuries, such as placental abruption and uterine rupture. Particularly unusual situations, such as a ruptured ectopic pregnancy in a trauma patient, are presented. Although pregnant trauma patients are infrequently encountered, familiarity with imaging findings of injuries in these patients is essential to providing the best care for the mother and fetus. PMID:24819793

Raptis, Constantine A; Mellnick, Vincent M; Raptis, Demetrios A; Kitchin, Douglas; Fowler, Kathryn J; Lubner, Meghan; Bhalla, Sanjeev; Menias, Christine O

2014-01-01

27

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

28

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

29

Type II collagen is a target antigen of clonally expanded T cells in the synovium of patients with rheumatoid arthritis  

PubMed Central

OBJECTIVE—To investigate whether type II collagen (CII) is recognised by oligoclonally expanded synovial T cells of patients with rheumatoid arthritis (RA).?METHODS—Peripheral blood mononuclear cells (PBMC) from 15 RA patients were stimulated with CII in vitro. T cell clones expanded by such stimulation were compared with the clonally expanded synovial T cells by using T cell receptor (TCR) B chain gene specific reverse transcription-polymerase chain reaction and subsequent single strand conformation polymorphism analyses.?RESULTS—Stimulation of the heterogeneous peripheral T cells with CII induced clonal expansion of T cells. In three of 15 patients, a proportion of these clones (approximately 17% to 25%) was found to be identical to expanded T cell clones in the synovium in vivo.?CONCLUSION—T cell clones that had TCR CDR3 sequences identical to those induced by purified CII were found in a proportion of RA patients. This finding suggests that CII is recognised by T cells that accumulate clonally in RA joints. Oligoclonal T cell expansion in RA joints is probably driven, at least in part, by intra-articular components such as CII.?? PMID:10381490

Sekine, T.; Kato, T.; Masuko-Hongo, K.; Nakamura, H.; Yoshino, S.; Nishioka, K.; Yamamoto, K.

1999-01-01

30

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

31

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

32

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

33

Selling the female image as mental patient  

Microsoft Academic Search

Tabulations of the sex and role (patient, helping professional, other) of all human images found in advertisements for psychoactive drugs in one half of the issues of The American Journal of Psychiatry from years 1963 to 1974 were made. Women were found to be portrayed as mentally ill significantly more often than men, while the images of men were used

David W. Stockburger; James O. Davis

1978-01-01

34

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

35

Ex Vivo Expanded Natural Killer Cells Demonstrate Robust Proliferation In Vivo In High-Risk Relapsed Multiple Myeloma Patients  

PubMed Central

Highly activated/expanded natural killer (NK) cells can be generated via stimulation with the HLA-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 haplo-identical 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 1×108 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 units/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

36

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

37

Clonally expanded plasma cells in the cerebrospinal fluid of patients with central nervous system autoimmune demyelination produce "oligoclonal bands".  

PubMed

Clonally expanded plasma cells (cePC) and oligoclonal IgG (oligoclonal bands, OCB) in the cerebrospinal fluid (CSF) suggest an involvement of B cell mechanisms in autoimmune CNS demyelination. Due to their CSF-restricted occurrence, OCB are commonly believed to be the products of B cells inside the borders of the blood brain barrier. A comparison of CSF cell Ig transcriptomes and CSF-Ig proteomes recently demonstrated, that in multiple sclerosis patients CSF cells are the origin of CSF immunoglobulins. We expand these findings by applying anti-idiotypic antibodies to detect specific heavy chain CDR3 idiotopes of cePC-produced antibodies amongst OCB in the CSF of a patient each with MS and acute disseminated encephalomyelitis. PMID:19900722

von Büdingen, Hans-Christian; Gulati, Monica; Kuenzle, Sandra; Fischer, Katja; Rupprecht, Tobias A; Goebels, Norbert

2010-01-25

38

A comparison of balloon-expandable-stent implantation with balloon angioplasty in patients with coronary artery disease  

Microsoft Academic Search

BACKGROUND. Balloon-expandable coronary-artery stents were developed to prevent coronary restenosis after coronary angioplasty. These devices hold coronary vessels open at sites that have been dilated. However, it is unknown whether stenting improves long-term angiographic and clinical outcomes as compared with standard balloon angioplasty. METHODS. A total of 520 patients with stable angina and a single coronary-artery lesion were randomly assigned

Patrick W. Serruys; Peter de Jaegere; Ferdinand Kiemeneij; C. M. Miguel; Wolfgang Rutsch; Guy Heyndrickx; Hakan Emanuelsson; Jean Marco; Victor Legrand; Pierre Materne; Jorge Belardi; Ulrich Sigwart; Antonio Colombo; Jean Jacques Goy; Paul van den Heuvel; Juan Delcan; Marie-angele Morel

1994-01-01

39

The effect of a vertical expandable prosthetic titanium rib on shoulder balance in patients with congenital scoliosis  

Microsoft Academic Search

Purpose  To evaluate the effect of a vertical expandable prosthetic titanium rib (VEPTR) on shoulder balance in patients with congenital\\u000a scoliosis.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Fifteen patients had a thoracic congenital scoliosis. The Cobb angles of the thoracic primary curves were measured. Preoperative\\u000a measurements of the coracoid height difference (CHD; expressed in millimeters) and the clavicular tilt angle difference (CTAD;\\u000a expressed in degrees) were performed

Mohamed Ahmed Samy; Zayed Saleh Al Zayed; Mahmood Farouk Shaheen

2009-01-01

40

The effect of a vertical expandable prosthetic titanium rib on shoulder balance in patients with congenital scoliosis  

PubMed Central

Purpose To evaluate the effect of a vertical expandable prosthetic titanium rib (VEPTR) on shoulder balance in patients with congenital scoliosis. Methods Fifteen patients had a thoracic congenital scoliosis. The Cobb angles of the thoracic primary curves were measured. Preoperative measurements of the coracoid height difference (CHD; expressed in millimeters) and the clavicular tilt angle difference (CTAD; expressed in degrees) were performed for all patients. All of the patients were treated with VEPTR open wedge thoracostomy. Result There was a statistically significant improvement in thoracic Cobb angle. At the end of follow-up there was a significant improvement in CHD; all but three of the patients had CHD < 9 mm. Preoperatively, CTAD was 8.9°. It improved to 4.4° postoperatively and significantly decreased to 3.9° by the end of follow-up. Complications included device migration (one patient), infection (one patient), and pedicle screw loosening or displacement (two patients). Conclusion VEPTR is able to produce a modest intraoperative correction of shoulder imbalance. PMID:19730916

Al Zayed, Zayed Saleh; Shaheen, Mahmood Farouk

2009-01-01

41

Megahertz Schlieren Imaging of Shock Structure and Sound Waves in Under-Expanded, Impinging Jets  

E-print Network

The accompanying fluid dynamics videos visualize the temporal evolution of shock structures and sound waves in and around an under-expanded jet that is impinging on a rigid surface at varying pressure ratios. The recordings were obtained at frame rates of 500 kHz to 1 Mhz using a novel pulsed illumination source based on a high power light emitting diode (LED) which is operated in pulsed current mode synchronized to the camera frame rate.

Willert, Christian; Soria, Julio

2010-01-01

42

How to image patients with spine pain.  

PubMed

Different radiological methods play an important role in the work-up of patients complaining of spine pain. Depending on the symptoms and the suspected underlying etiology different methods are selected. In the following presentation we briefly present the different radiological and magnetic resonance tomography methods that are at hand, give some guidance in which method to use, and present the typical imaging findings in some of the most common conditions that presents with spine pain. PMID:25048978

Siemund, R; Thurnher, M; Sundgren, P C

2015-05-01

43

Sexual Abuse Images in Cyberspace: Expanding the Ecology of the Child  

ERIC Educational Resources Information Center

Cyberspace has added a new dimension to the ecology of children made the subjects of sexual abuse images distributed online. These images cannot be permanently removed and can continue to circulate in cyberspace forever. A review of the current literature suggests that helping professionals are not consistently aware of or do not probe…

Martin, Jennifer; Alaggia, Ramona

2013-01-01

44

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

45

Expanded palette of Nano-lanterns for real-time multicolor luminescence imaging.  

PubMed

Fluorescence live imaging has become an essential methodology in modern cell biology. However, fluorescence requires excitation light, which can sometimes cause potential problems, such as autofluorescence, phototoxicity, and photobleaching. Furthermore, combined with recent optogenetic tools, the light illumination can trigger their unintended activation. Because luminescence imaging does not require excitation light, it is a good candidate as an alternative imaging modality to circumvent these problems. The application of luminescence imaging, however, has been limited by the two drawbacks of existing luminescent protein probes, such as luciferases: namely, low brightness and poor color variants. Here, we report the development of bright cyan and orange luminescent proteins by extending our previous development of the bright yellowish-green luminescent protein Nano-lantern. The color change and the enhancement of brightness were both achieved by bioluminescence resonance energy transfer (BRET) from enhanced Renilla luciferase to a fluorescent protein. The brightness of these cyan and orange Nano-lanterns was ?20 times brighter than wild-type Renilla luciferase, which allowed us to perform multicolor live imaging of intracellular submicron structures. The rapid dynamics of endosomes and peroxisomes were visualized at around 1-s temporal resolution, and the slow dynamics of focal adhesions were continuously imaged for longer than a few hours without photobleaching or photodamage. In addition, we extended the application of these multicolor Nano-lanterns to simultaneous monitoring of multiple gene expression or Ca(2+) dynamics in different cellular compartments in a single cell. PMID:25831507

Takai, Akira; Nakano, Masahiro; Saito, Kenta; Haruno, Remi; Watanabe, Tomonobu M; Ohyanagi, Tatsuya; Jin, Takashi; Okada, Yasushi; Nagai, Takeharu

2015-04-01

46

Expanded palette of Nano-lanterns for real-time multicolor luminescence imaging  

PubMed Central

Fluorescence live imaging has become an essential methodology in modern cell biology. However, fluorescence requires excitation light, which can sometimes cause potential problems, such as autofluorescence, phototoxicity, and photobleaching. Furthermore, combined with recent optogenetic tools, the light illumination can trigger their unintended activation. Because luminescence imaging does not require excitation light, it is a good candidate as an alternative imaging modality to circumvent these problems. The application of luminescence imaging, however, has been limited by the two drawbacks of existing luminescent protein probes, such as luciferases: namely, low brightness and poor color variants. Here, we report the development of bright cyan and orange luminescent proteins by extending our previous development of the bright yellowish-green luminescent protein Nano-lantern. The color change and the enhancement of brightness were both achieved by bioluminescence resonance energy transfer (BRET) from enhanced Renilla luciferase to a fluorescent protein. The brightness of these cyan and orange Nano-lanterns was ?20 times brighter than wild-type Renilla luciferase, which allowed us to perform multicolor live imaging of intracellular submicron structures. The rapid dynamics of endosomes and peroxisomes were visualized at around 1-s temporal resolution, and the slow dynamics of focal adhesions were continuously imaged for longer than a few hours without photobleaching or photodamage. In addition, we extended the application of these multicolor Nano-lanterns to simultaneous monitoring of multiple gene expression or Ca2+ dynamics in different cellular compartments in a single cell. PMID:25831507

Takai, Akira; Nakano, Masahiro; Saito, Kenta; Haruno, Remi; Watanabe, Tomonobu M.; Ohyanagi, Tatsuya; Jin, Takashi; Okada, Yasushi; Nagai, Takeharu

2015-01-01

47

Sexual abuse images in cyberspace: expanding the ecology of the child.  

PubMed

Cyberspace has added a new dimension to the ecology of children made the subjects of sexual abuse images distributed online. These images cannot be permanently removed and can continue to circulate in cyberspace forever. A review of the current literature suggests that helping professionals are not consistently aware of or do not probe possibilities of online sexual victimization in the investigation, assessment, and treatment of child sexual abuse. Nor is this issue adequately addressed in their education and training. There are gaps in the literature regarding how to identify and provide treatment for these children. New assessment and treatment targets are needed to enhance existing practice approaches. A contemporary ecological model that incorporates an explicit consideration of the cybersystem is provided as a starting point for practitioners to be aware of the possibility that images of child sexual abuse were recorded and distributed online. PMID:23682766

Martin, Jennifer; Alaggia, Ramona

2013-01-01

48

Unusual phenotype and function of an expanded subpopulation of T cells in patients with haemopoietic disorders.  

PubMed Central

We have studied two patients, one with red cell aplasia and the other with neutropenia. Both showed lymphocytosis. In both cases, 90-100% of E rosetting cells were T cells as defined by the monoclonal antibodies UCHT1 and OKT3. The majority of these cells also carried the OKT8 suppressor/cytotoxic marker and were HLA-DR- and Fc gamma R-positive. In spite of the similarity of this phenotype to that reported for suppressor cells, these cells failed to suppress pokeweed mitogen-induced polyclonal Ig synthesis. Cells from both patients also failed to respond significantly to Con A and PHA. They were, however, unable to suppress the Con A responses of normal donors although cells from one patient were able to suppress completely a normal PHA response. These results demonstrate the existence of a genuine subset of T cells with Fc gamma receptors but suggest that not all such cells have typical suppressor function. PMID:7026093

Callard, R E; Smith, C M; Worman, C; Linch, D; Cawley, J C; Beverley, P C

1981-01-01

49

Imaging in Patients with Merkel Cell Carcinoma  

PubMed Central

Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine tumor of the skin with a mortality rate of approximately 25% (Peloschek et al., 2010). Accurate assessment of nodal involvement in patients with MCC predicts significantly overall outcome (Smith et al., 2012 and Ortin-Perez et al., 2007). Due to the rarity of this highly aggressive disease, only a few imaging reports on MCC were published, and subsequently still to date no accepted imaging algorithm for MCC is available. For primary staging of MCC, general recommendations have included ultrasonography, chest X-ray CT, and MRI, but recent articles show that the use of sentinel node and FDG-PET/PET-CT is gaining more and more importance. PMID:23476783

Enzenhofer, Elisabeth; Ubl, Philipp; Czerny, Christian; Erovic, Boban M.

2013-01-01

50

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

51

Vorapaxar expands antiplatelet options. Which patients may benefit from thrombin receptor antagonism?  

PubMed

Vorapaxar is the first substance of a new class of antiplatelet drugs that has been tested in large clinical trials. The protease-activated receptor 1 (PAR-1) antagonist inhibits thrombin-induced platelet activation to prevent atherothrombosis. In the phase 3 trials TRACER (acute coronary syndrome) and TRA 2P-TIMI 50 (stable atherosclerosis) reducing ischemic events with vorapaxar came at the cost of bleeding. TRACER compared vorapaxar to placebo in 12,944 patients who had non-ST-segment elevation acute coronary syndromes on top of contemporary treatment including dual antiplatelet therapy (aspirin and clopidogrel). Vorapaxar reduced ischemic events non-significantly, but increased bleeding significantly, therefore not justifying triple antiplatelet therapy in this setting. Follow-up was stopped early because of bleeding. TRA 2P-TIMI 50 examined 26,449 patients who had a history of myocardial infarction, ischemic stroke, or peripheral arterial disease. Vorapaxar reduced ischemic events and increased bleeding both significantly. Recruitment of patients with prior stroke was stopped early. Net clinical outcome and subgroup analyses suggested that vorapaxar could be beneficial for patients with prior myocardial infarction - but no history of stroke. PMID:22777302

Duerschmied, D; Bode, C

2012-01-01

52

Advances and New Approaches in Imaging Technology: Expanding the Reach of High-Content Analysis  

NSDL National Science Digital Library

Over the past decade, high-content analysis (HCA) has become widely adopted in both academic research and drug discovery laboratories. This webinar will discuss the pros and cons of the most commonly used imaging methods across a range of applications and highlight recent advances which promise to increase the power of HCA to answer more complex research questions and to yield deeper insights to advance the drug discovery process.

n/a n/a (AAAS; )

2011-05-25

53

A PILOT IMAGING LINE SURVEY OF RW LMi AND IK Tau USING THE EXPANDED VERY LARGE ARRAY  

SciTech Connect

We report on a pilot imaging line survey (36.0-37.0 GHz, with {approx}1 km s{sup -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 HC{sub 3}N (J = 4{yields}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{yields}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 HC{sub 7}N (J = 32{yields}31) emission from RW LMi.

Claussen, M. J.; Sjouwerman, L. O.; Rupen, M. P. [National Radio Astronomy Observatory, Socorro, NM 87801 (United States); Olofsson, H.; Schoeier, F. L.; Bergman, P. [Onsala Space Observatory, Department of Radio and Space Science, Chalmers University of Technology, 43992 Onsala (Sweden); Knapp, G. R. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

2011-09-20

54

Optimizing HIV Care by Expanding the Nursing Role: Patient and Provider Perspectives  

PubMed Central

Aim This paper is a report of a study conducted to explore HIV healthcare services from the perspectives of both healthcare providers and patients in order to understand how to optimize HIV nursing care. Background In China, healthcare providers usually first diagnose HIV in a general hospital. Then, HIV-positive individuals are transferred to a specialist hospital. Between healthcare providers and healthcare institutions, there are many gaps in the process from diagnosis to treatment. Methods One focus group with 6 healthcare providers and 29 in-depth interviews with people living with HIV/AIDS were conducted during 2005. Findings Patients who were diagnosed with HIV in a general hospital often did not discuss their condition with a healthcare provider before being sent to a specialist hospital. Furthermore, since the patients had already been diagnosed, healthcare providers in the specialist hospital did not deal adequately with the disclosure process and emotional reactions to the diagnosis. They reported feeling overwhelmed in their role in providing healthcare services. Nurses reported that they were responsible for many “non-nursing” tasks and did not have the opportunity to give the type of care they were trained to offer. Conclusion Optimizing HIV care in China will involve establishing clear boundaries between general and specialist hospitals and a division of labour among healthcare providers that eases the burden of care and takes advantage of the full scope of practice that nurses are trained to provide. PMID:20423409

Chen, Wei-Ti; Shiu, Cheng-Shi; Simoni, Jane; Fredriksen-Goldsen, Karen; Zhang, Fujie; Zhao, Hongxin

2009-01-01

55

Identification of an HD patient with a (CAG) 180 repeat expansion and the propagation of highly expanded CAG repeats in lambda phage  

Microsoft Academic Search

The Huntington’s disease mutation has been identified as a CAG\\/polyglutamine repeat expansion in a large gene of unknown\\u000a function. In order to develop the transgenic systems necessary to uncover the molecular pathology of this disorder, it is\\u000a necessary to be able to manipulate highly expanded CAG repeats in a cloned form. We have identified a patient with an expanded\\u000a allele

Kirupa Sathasivam; Iheoma Amaechi; Laura Mangiarini; Gillian Bates

1997-01-01

56

Mesenchymal stromal cells from patients with acute myeloid leukemia have altered capacity to expand differentiated hematopoietic progenitors.  

PubMed

The bone marrow microenvironment may be permissive to the emergence and progression of acute myeloid leukemia (AML). Studying interactions between the microenvironment and leukemia cells should provide new insight for therapeutic advances. Mesenchymal stromal cells (MSCs) are central to the maintenance of the hematopoietic niche. Here we compared the functions and gene expression patterns of MSCs derived from bone marrow aspirates of healthy donors and patients with AML. MSCs expanded from AML patients had heterogeneous morphology and displayed a wide range of proliferation capacity compared to MSCs from healthy controls. The ability of AML-MSCs to support the expansion of committed hematopoietic progenitors from umbilical cord blood-derived CD34(+) cells may be impaired while the expression of genes associated with maintaining hematopoietic quiescence appeared to be increased in AML-MSCs compared to healthy donors. These results highlight important potential differences in the biologic profile of MSCs from AML patients compared to healthy donors that may contribute to the emergence or progression of leukemia. PMID:25703353

Chandran, Priya; Le, Yevgeniya; Li, Yuhua; Sabloff, Mitchell; Mehic, Jelica; Rosu-Myles, Michael; Allan, David S

2015-04-01

57

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

58

Megapixel imaging camera for expanded H{sup {minus}} beam measurements  

SciTech Connect

A charge coupled device (CCD) imaging camera system has been developed as part of the Ground Test Accelerator project at the Los Alamos National Laboratory to measure the properties of a large diameter, neutral particle beam. The camera is designed to operate in the accelerator vacuum system for extended periods of time. It would normally be cooled to reduce dark current. The CCD contains 1024 {times} 1024 pixels with pixel size of 19 {times} 19 {mu}m{sup 2} and with four phase parallel clocking and two phase serial clocking. The serial clock rate is 2.5{times}10{sup 5} pixels per second. Clock sequence and timing are controlled by an external logic-word generator. The DC bias voltages are likewise located externally. The camera contains circuitry to generate the analog clocks for the CCD and also contains the output video signal amplifier. Reset switching noise is removed by an external signal processor that employs delay elements to provide noise suppression by the method of double-correlated sampling. The video signal is digitized to 12 bits in an analog to digital converter (ADC) module controlled by a central processor module. Both modules are located in a VME-type computer crate that communicates via ethernet with a separate workstation where overall control is exercised and image processing occurs. Under cooled conditions the camera shows good linearity with dynamic range of 2000 and with dark noise fluctuations of about {plus_minus}1/2 ADC count. Full well capacity is about 5{times}10{sup 5} electron charges.

Simmons, J.E.; Lillberg, J.W.; McKee, R.J.; Slice, R.W.; Torrez, J.H. [Los Alamos National Lab., NM (United States); McCurnin, T.W.; Sanchez, P.G. [EG and G Energy Measurements, Inc., Los Alamos, NM (United States). Los Alamos Operations

1994-02-01

59

Expanding patient access to quality medication-related information: the potential of medication hotlines to improve patient adherence in schizophrenia.  

PubMed

Medication nonadherence is a widespread problem that compromises treatment outcomes, particularly in schizophrenia. Weersink et al. (Soc Psychiatry Psychiatr Epidemiol, 2015) describe telephone calls to a national medicines information line, with a focus on queries related to antipsychotic medications. Their analysis of callers' questions and concerns offers a valuable window into patient and caregiver perspectives. Given that many callers reported that they had not shared these concerns with a health care provider, this study also highlights the capacity of medication hotlines to address unmet needs. Establishing and maintaining long-term treatment regimens is a complex task, and truly patient-centered care requires a variety of creative and accessible support resources. Medication lines have the potential to serve as a resource and to provide proactive and timely adherence support. PMID:25859753

Pettit, Amy R; Marcus, Steven C

2015-05-01

60

Expanding the scope of fiduciary duties to fill a gap in the law: the role of nonprofit hospital directors to ensure patient safety.  

PubMed

In the wake of the patient safety movement, there is a glaring disconnect between the increasing responsibilities placed on hospital board members and the limited accountability for those board members if they fail to meet their responsibilities. This Article discusses how the effectiveness of new patient safety laws is diminished by the lack of accountability of nonprofit board members. The Article suggests that an expanded notion of corporatefiduciary duties, enhanced by shifts in social norms, would contribute to patient safety reform. PMID:15968941

Kaput, Sarah

2005-01-01

61

Dynamic imaging of seizure activity in pediatric epilepsy patients  

PubMed Central

Objective To investigate the feasibility of using noninvasive EEG source imaging approach to image continuous seizure activity in pediatric epilepsy patients. Methods Nine pediatric patients with medically intractable epilepsy were included in this study. Eight of the patients had extratemporal lobe epilepsy and one had temporal lobe epilepsy. All of the patients underwent resective surgery and seven of them underwent intracranial EEG (iEEG) monitoring. The ictal EEG was analyzed using a noninvasive dynamic seizure imaging (DSI) approach. The DSI approach separates scalp EEGs into independent components and extracts the spatio-temporal ictal features to achieve dynamic imaging of seizure sources. Surgical resection and intracranial recordings were used to validate the noninvasive imaging results. Results The DSI determined seizure onset zones (SOZs) in these patients were localized within or in close vicinity to the surgically resected region. In the seven patients with intracranial monitoring, the estimated seizure onset sources were concordant with the seizure onset zones of iEEG. The DSI also localized the multiple foci involved in the later seizure propagation, which were confirmed by the iEEG recordings. Conclusions Dynamic seizure imaging can noninvasively image the seizure activations in pediatric patients with both temporal and extratemporal lobe epilepsy. Significance EEG seizure imaging can potentially be used to noninvasively image the SOZs and aid the pre-surgical planning in pediatric epilepsy patients. PMID:22608485

Lu, Yunfeng; Yang, Lin; Worrell, Gregory A.; Brinkmann, Benjamin; Nelson, Cindy; He, Bin

2012-01-01

62

Exercise thallium imaging in patients with diabetes mellitus. Prognostic implications  

SciTech Connect

We used exercise thallium 201 imaging in 123 patients with diabetes mellitus (77 men and 46 women, aged 56 +/- 8 years), 75% of whom had angina pectoris (typical or atypical). During exercise testing, 18 patients (15%) had angina pectoris, 28 (23%) had ischemic ST changes, and 69 (56%) had abnormal thallium images. During follow-up (up to 36 months), there were 12 cardiac events; four patients died of cardiac causes and eight had nonfatal acute myocardial infarction. Univariate and multivariate survival analysis identified two independent predictors of cardiac events: the event rate was significantly less in patients with normal images and exercise heart rate over 120 beats per minute than in patients with abnormal images and exercise heart rate of 120 beats per minute or less (0% vs 22%). The patients with abnormal images or exercise heart rate of 120 beats per minute or less had an intermediate event rate (11.5%). Furthermore, two of the 54 patients with normal images and ten of 69 patients with abnormal images had subsequent cardiac events. Thus, exercise thallium imaging is useful in risk stratification in patients with diabetes mellitus.

Felsher, J.; Meissner, M.D.; Hakki, A.H.; Heo, J.; Kane-Marsch, S.; Iskandrian, A.S.

1987-02-01

63

The influence of patient thickness and imaging system on patient dose and physical image quality in digital chest imaging.  

PubMed

The aim of this work was to study the influence of patient thickness, tube voltage and image detector on patient dose, contrast and ideal observer signal-to-noise ratio (SNR(I)), for pathological details positioned at different regions in the image in posterior-anterior (PA) chest radiology. A Monte Carlo computational model was used to compute measures of physical image quality (contrast, SNR(I)) and patient effective dose, E. Two metastasis-like details positioned in the central right lung and right lung near the spine, respectively, were studied. The tube voltage was varied between 100 and 150 kV and the patient thickness between 20 and 28 cm. Both, a computed radiography (CR) system and a direct radiography (DR) system, were investigated. The DR system provides both lower doses and better image quality compared with the CR system. The SNR(I)2/E is approximately 2.9 times higher for the DR system compared with the CR system. PMID:15933124

Ullman, Gustaf; Sandborg, Michael; Dance, David R; Hunt, Roger; Alm Carlsson, Gudrun

2005-01-01

64

Comparison of balloon-expandable versus self-expandable valves for transcatheter aortic valve implantation in patients with low-gradient severe aortic stenosis and preserved left ventricular ejection fraction.  

PubMed

A relevant proportion of patients, classified as severe aortic stenosis on the basis of valve area ?1 cm(2), have a mean transvalvular gradient ?40 mm Hg, despite a preserved left ventricular ejection fraction (LGSAS). We assessed the clinical and hemodynamic impact of transcatheter aortic valve implantation in patients with symptomatic LGSAS at high risk for surgery or inoperable, according to the type of percutaneous valve implanted. Ninety-five patients received an Edwards SAPIEN valve (Edwards Lifesciences, Irvine, California) and 51 received a Medtronic CoreValve (Medtronic, Inc., Minneapolis, Minnesota). The hemodynamic performance of the 2 valves was similar in term of final transvalvular gradients (10 mm Hg, p = 0.069). Early mortality rate was 7% and was not different between the 2 valves (p = 0.73). During follow-up, cardiovascular mortality rate was similar between groups, and valve type was not a predictor of outcome (p = 0.72). Estimated survival by Kaplan-Meier at 2 years was 70%. At multivariate analysis, life-threatening or major bleeding, postprocedural aortic insufficiency, and acute kidney injury were the major predictors of an adverse outcome. In patients with LGSAS treated by transcatheter aortic valve implantation, the use of balloon-expandable versus self-expandable valves resulted in similar hemodynamic, early, and long-term clinical outcomes. PMID:25620039

Covolo, Elisa; Saia, Francesco; Napodano, Massimo; Frigo, Anna Chiara; Agostoni, Pierfrancesco; Mojoli, Marco; Fraccaro, Chiara; Ciuca, Cristina; Presbitero, Patrizia; Moretti, Claudio; D'Ascenzo, Fabrizio; Tarantini, Giuseppe

2015-03-15

65

Colloquial descriptions of body image in older surgical patients  

Microsoft Academic Search

Major surgery and associated experiences in critical care settings affect patients’ perceptions of their body images. This paper discusses several colloquial terms related to body image used in interviews by elderly patients following major surgery for abdominal aortic aneurysm. The terms ‘badly failed, and well mended’, and ‘out of sorts’, and ‘in tune with my body’ recurred. These referred to

Pat Deeny; Michael Kirk-Smith

2000-01-01

66

Brain Perfusion Imaging in Asymptomatic Patients Receiving Cyclosporin  

Microsoft Academic Search

BACKGROUND AND PURPOSE:Cyclosporin has neurotoxic effects in a significant number of transplant patients that are associated with characteristic findings on MR images. Focal abnormalities in cerebral perfusion have been implicated in the pathophysiology of cyclosporin neurotoxicity. In the clinically asymptomatic patient, however, it is not known whether any imaging evidence of cyclosporin's effect on the brain is demonstrable. Our hypothesis

Tarang N. Sheth; Masanori Ichise; Walter Kucharczyk

67

Multidetector CT imaging features of solid pseudopapillary tumours of the pancreas in male patients: distinctive imaging features with female patients  

PubMed Central

Objective: To describe multidetector CT imaging features of solid pseudopapillary tumours (SPTs) in male patients and to compare these imaging features with those found in female patients. Methods: The institutional review board approved this retrospective study. We included the CT images of 72 patients (M:F?=?12:60; mean age, 35.0 years) diagnosed with SPT by histology. CT images were reviewed on the following: location of the tumour, maximal diameter, shape, margin and the fraction of the tumour composition. Statistical differences in CT imaging features were analysed. Results: Male patients with SPTs were significantly older than female patients (42.4 years vs 33.4 years, p?=?0.0408) and the mean size of the SPTs in male patients was larger (6.3?cm vs 4.6?cm, p?=?0.0413) than that of SPTs in female patients. Lobulated shape of the SPTs was most frequent in male patients, whereas oval shape was most frequent in female patients (p?=?0.0133). SPTs in male patients tended to have a solid component (p?=?0.0434). Progressive enhancement in the solid portion of the tumour was seen in 9 (81.8%) of 11 SPTs in male patients and in 30 (79.0%) of 38 SPTs in female patients on multiphasic CT. Conclusion: The imaging features of SPTs in male patients usually appeared as a somewhat large-sized solid mass with a lobulated margin and progressive enhancement. These imaging features may help to differentiate SPTs from other pancreatic tumours for their proper management. Advances in knowledge: SPTs in male patients appear as somewhat large-sized solid masses with lobulated margins, and this form occurs more frequently in older male patients than in female patients. PMID:24472726

Park, M J; Kim, J K; Kim, Y C; Park, M-S; Yu, J-S; Kim, Y B; Lee, D

2014-01-01

68

Expanded Notation  

NSDL National Science Digital Library

With this step-by-step, interactive video from StudyJams students can earn more about expanded notation. Expanded notation, also called expanded form, is a handy way to write numbers that shows the place value of each digit. It looks like an addition problem and will help you break numbers down and understand their place value. A short, self-checking quiz is also included with this link.

StudyJam – Scholastic

2011-06-28

69

Contemporary imaging modalities for the surveillance of patients with renal cell carcinoma.  

PubMed

In recent years, there have been multiple advances in imaging technologies that have improved the surveillance for recurrence of neoplasms. Multidetector row CT and dynamic contrast enhanced MRI now provide excellent anatomic detail and are beginning to show functional detail as the rapid capture of images following contrast administration improves. Positron emission tomography is emerging as a useful tool in evaluating patients with suspected metastatic disease to the abdomen and bone, particularly when combined with CT. The role of ultrasound in the surveillance of renal cell carcinoma is yet unclear, but its role may be expanding with use of newly developed contrast drugs. Herein we review the relevance of these modalities to the follow-up of patients with renal cell carcinoma. PMID:17239315

Tollefson, Matthew K; Takahashi, Naoki; Leibovich, Bradley C

2007-01-01

70

Wave Expander  

Microsoft Academic Search

A schematic description of the design of a wave expander is presented. A mathematical model of the operation process has been substantiated. The operational characteristics of a reciprocating wave expander have been obtained within the framework of the numerical integration of the system of nonstationary gas-dynamics equations in a one-dimensional formulation. The stages of the operation process have been considered

S. V. Bulovich; R. L. Petrov

2002-01-01

71

Body image disturbance in patients with acne vulgaris.  

PubMed

Psychosocial outcome measures, which attempt to examine acne from the patient's perspective, have become increasingly important in dermatology research. One such measure is the Body Image Disturbance Questionnaire. The authors' primary aim was to determine the validity and internal consistency of the Body Image Disturbance Questionnaire in patients with acne vulgaris. The secondary aim was to investigate the relationship between body image disturbance and quality of life. This cross-sectional investigation included 52 consecutive acne patients presenting to an outpatient dermatology clinic. Subjects completed the Body Image Disturbance Questionnaire, Skindex-16, and other body image and psychosocial functioning measures. An objective assessment of acne was performed. The Body Image Disturbance Questionnaire was internally consistent and converged with other known body image indices. Body Image Disturbance Questionnaire scores also correlated with Skindex-16 scores, confirming that quality of life and body image are related psychosocial constructs. The Body Image Disturbance Questionnaire appears to be an accurate instrument that can assess appearance-related concern and impairment in patients with acne vulgaris. Limitations include a small sample size and the cross-sectional design. PMID:21779418

Bowe, Whitney P; Doyle, Amanda K; Crerand, Canice E; Margolis, David J; Shalita, Alan R

2011-07-01

72

Body Image Disturbance in Patients with Acne Vulgaris  

PubMed Central

Psychosocial outcome measures, which attempt to examine acne from the patient's perspective, have become increasingly important in dermatology research. One such measure is the Body Image Disturbance Questionnaire. The authors' primary aim was to determine the validity and internal consistency of the Body Image Disturbance Questionnaire in patients with acne vulgaris. The secondary aim was to investigate the relationship between body image disturbance and quality of life. This cross-sectional investigation included 52 consecutive acne patients presenting to an outpatient dermatology clinic. Subjects completed the Body Image Disturbance Questionnaire, Skindex-16, and other body image and psychosocial functioning measures. An objective assessment of acne was performed. The Body Image Disturbance Questionnaire was internally consistent and converged with other known body image indices. Body Image Disturbance Questionnaire scores also correlated with Skindex-16 scores, confirming that quality of life and body image are related psychosocial constructs. The Body Image Disturbance Questionnaire appears to be an accurate instrument that can assess appearance-related concern and impairment in patients with acne vulgaris. Limitations include a small sample size and the cross-sectional design. PMID:21779418

Bowe, Whitney P.; Crerand, Canice E.; Margolis, David J.; Shalita, Alan R.

2011-01-01

73

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

74

Impact of sirolimus-eluting stents on outcome in diabetic patients: A SIRIUS (SIRolImUS-coated Bx Velocity balloon-expandable stent in the treatment of patients with de novo coronary artery lesions) substudy  

Microsoft Academic Search

Background—Randomized clinical trials have shown that a sirolimus-eluting stent significantly reduces restenosis after percutaneous coronary revascularization. Diabetic patients are known to have a higher risk of restenosis compared with nondiabetic patients. The purpose of this analysis was to determine the impact of sirolimus-eluting stents on outcomes of diabetic compared with nondiabetic patients. Methods and Results—The SIRIUS (SIRolImUS-coated Bx Velocity balloon-expandable

Issam Moussa; Martin B. Leon; Donald S. Baim

2004-01-01

75

Imaging Approaches to Patients with Polycystic Kidney Disease  

PubMed Central

Imaging is an important approach to diagnosis, monitoring and predicting outcomes for patients with Autosomal Dominant polycystic Kidney Disease (ADPKD). This paper reviews three common clinical imaging techniques, ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI) and their role in management of ADPKD. Ultrasonographic criteria for diagnosis in children and adults are reviewed. Total kidney volume (TKV), as measured by MRI, is suggested as important potential marker to determine disease progression and overall prognosis. Renal blood flow (RBF) and a novel approach to interpreting non-cystic renal parenchymal by CT images are other innovative imaging approaches described. PMID:21784272

Chapman, Arlene B.; Wei, Wenjing

2011-01-01

76

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

77

Expanding Universe  

NASA Astrophysics Data System (ADS)

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 ...

Murdin, P.

2000-11-01

78

Image-Guided Drainage of Pericardial Effusions in Oncology Patients  

Microsoft Academic Search

The purpose of this study was to report our clinical experience with image-guided drainage of pericardial effusions in oncology\\u000a patients. IRB approval was obtained for this retrospective, HIPAA-compliant study. From November 2002 to January 2008, 40\\u000a patients underwent 43 image-guided drainages of pericardial effusions. The medical records were reviewed to analyze the technical\\u000a aspects of the procedures, complications, and clinical

Alda Tam; Joe E. Ensor; Holly Snyder; Sanjay Gupta; Jean-Bernard Durand; Michael J. Wallace

2009-01-01

79

A body image scale for use with cancer patients  

Microsoft Academic Search

Body image is an important endpoint in quality of life evaluation since cancer treatment may result in major changes to patients' appearance from disfiguring surgery, late effects of radiotherapy or adverse effects of systemic treatment. A need was identified to develop a short body image scale (BIS) for use in clinical trials. A 10-item scale was constructed in collaboration with

P Hopwood; I Fletcher; A Lee; S Al Ghazal

2001-01-01

80

IMAGE ANALYSIS OF DOPPLER ECHOCARDIOGRAPHY FOR PATIENTS WITH ATRIAL FIBRILLATION  

E-print Network

IMAGE ANALYSIS OF DOPPLER ECHOCARDIOGRAPHY FOR PATIENTS WITH ATRIAL FIBRILLATION Oron Shechner(1, Tel Aviv University, Tel-Aviv, Israel 69978 (2)The Neufeld Cardiac Research Institute, Sheba Medical from Doppler Echocardiography images. Currently, manual methods are subject to large inter- and intra

Greenspan, Hayit

81

First successful treatment of a circumferential intramural esophageal dissection with perforation in a patient with eosinophilic esophagitis using a partially covered self-expandable metal stent.  

PubMed

Intramural esophageal dissection (IED) is a rare disease characterized by a partial (PIED) or circumferential (CIED) mucosal rupture. Whereas PIED responds well to nonoperative treatment, complicated courses have been reported necessitating surgery, up to the point of esophagectomy despite complex endoscopic interventions, in CIED. We report the first case of an iatrogenic CIED with perforation in a young patient with underlying eosinophilic esophagitis treated successfully by endoscopy alone, using a partially covered self-expandable metal stent. PMID:25683073

Fischer, Andreas; Höppner, Jens; Richter-Schrag, Hans-Jürgen

2015-02-01

82

Outcomes of patients with advanced non-small cell lung cancer treated with gefitinib (ZD1839, ‘Iressa’) on an expanded access study  

Microsoft Academic Search

Purpose: To investigate the anti-tumor activity and toxicity of the epidermal growth factor receptor (EGFR) inhibitor gefitinib (ZD1839 or Iressa™; AstraZeneca Pharmaceuticals, Wilmington, DE), in patients with advanced non-small cell lung cancer (NSCLC). Methods: This was an open label, expanded access program (EAP) of oral gefitinib administered at 250mg per day continuously until evidence of undue toxicity or disease progression.

Pasi A. Jänne; Sarada Gurubhagavatula; Beow Y. Yeap; Joan Lucca; Patricia Ostler; Arthur T. Skarin; Panos Fidias; Thomas J. Lynch; Bruce E. Johnson

2004-01-01

83

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

84

[Brain imaging of patients with memory disorders].  

PubMed

Indications for brain imaging include potentially treatable intracranial causes (e.g. normal-pressure hydrocephalus, tumors, subdural hematoma) and especially characteristic features of memory disorders and differential diagnostics of such conditions. Since the primary structural changes in the most common progressive memory disorder, Alzheimer's disease, are seen in the inner temporal lobe, appropriate imaging of these structures is essential in early diagnosis. PMID:22320104

Vanninen, Ritva; Mäntylä, Riitta; Salonen, Oili; Valanne, Leena; Rinne, Juha; Erkinjuntti, Timo

2011-01-01

85

Watermarking Medical Images with Anonymous Patient Identification to Verify Authenticity  

Microsoft Academic Search

Abstract: When dealing with medical image management, there is a need to ensure information ,authenticity and ,dependability. Being able to verify ,the information belongs to the correct patient and is issued from the right source is a major concern. Verification can help to reduce the risk of errors when,identifying documents,in daily practice or when sending a patient's Electronic Health Record.

Gouenou Coatrieux; Catherine Quantin; Julien Montagner; Maniane Fassa; François-andré Allaert; Christian Roux

2008-01-01

86

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

87

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

88

Watermarking medical images with anonymous patient identification to verify authenticity.  

PubMed

When dealing with medical image management, there is a need to ensure information authenticity and dependability. Being able to verify the information belongs to the correct patient and is issued from the right source is a major concern. Verification can help to reduce the risk of errors when identifying documents in daily practice or when sending a patient's Electronic Health Record. At the same time, patient privacy issues may appear during the verification process when the verifier accesses patient data without appropriate authorization. In this paper we discuss the combination of watermarking with different identifiers ranging from DICOM standard UID to an Anonymous European Patient Identifier in order to improve medical image protection in terms of authenticity and maintainability. PMID:18487808

Coatrieux, Gouenou; Quantin, Catherine; Montagner, Julien; Fassa, Maniane; Allaert, François-André; Roux, Christian

2008-01-01

89

Imaging of patients with congenital heart disease  

Microsoft Academic Search

Congenital defects most-commonly affect the heart, with an estimated incidence of up to 10 in 1,000 live births. Over the past few decades, mortality has decreased and subsequent survival has increased; approximately 90% of all patients with congenital heart disease (CHD) reach adulthood. Echocardiography is sufficient in most cases for prenatal and postnatal diagnosis of CHD and to plan an

Albert de Roos; Arno A. W. Roest

2011-01-01

90

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

91

Clonally expanded plasma cells in the cerebrospinal fluid of patients with central nervous system autoimmune demyelination produce “oligoclonal bands”  

Microsoft Academic Search

Clonally expanded plasma cells (cePC) and oligoclonal IgG (oligoclonal bands, OCB) in the cerebrospinal fluid (CSF) suggest an involvement of B cell mechanisms in autoimmune CNS demyelination. Due to their CSF-restricted occurrence, OCB are commonly believed to be the products of B cells inside the borders of the blood brain barrier. A comparison of CSF cell Ig transcriptomes and CSF-Ig

Hans-Christian von Büdingen; Monica Gulati; Sandra Kuenzle; Katja Fischer; Tobias A. Rupprecht; Norbert Goebels

2010-01-01

92

Metabolic imaging of patients with cardiomyopathy  

SciTech Connect

The cardiomyopathies comprise a diverse group of illnesses that can be characterized functionally by several techniques. However, the delineation of derangements of regional perfusion and metabolism have been accomplished only relatively recently with positron emission tomography (PET). Regional myocardial accumulation and clearance of 11C-palmitate, the primary myocardial substrate under most conditions, demonstrate marked spatial heterogeneity when studied under fasting conditions or with glucose loading. PET with 11C-palmitate permits the noninvasive differentiation of patients with nonischemic from ischemic dilated cardiomyopathy, since patients with ischemic cardiomyopathy demonstrate large zones of intensely depressed accumulation of 11C-palmitate, probably reflecting prior infarction. Patients with hypertrophic cardiomyopathy and Duchenne's muscular dystrophy demonstrate relatively unique patterns of myocardial abnormalities of perfusion and metabolism. The availability of new tracers and techniques for the evaluation of myocardial metabolism (11C-acetate), perfusion (H2(15)O), and autonomic tone (11-C-hydroxyephedrine) should facilitate further understanding of the pathogenesis of the cardiomyopathies.

Geltman, E.M. (Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (United States))

1991-09-01

93

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

94

Imaging the pyramidal tract in patients with brain tumors  

Microsoft Academic Search

The clinical usefulness of diffusion-weighted magnetic resonance imaging (DWI) of the pyramidal tract was evaluated in patients with brain tumors. Five normal volunteers and seven patients with glioma (n=4) or meningioma (n=3) near the pyramidal tract underwent coronal echo planar DWI. Greyscale DWIs in each of the three orthogonal diffusion gradients were transformed into graduations, color-coded as red, green or

Takashi Inoue; Hiroaki Shimizu; Takashi Yoshimoto

1999-01-01

95

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

96

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

97

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

98

Magnetic resonance imaging of patients with large vestibular aqueducts  

Microsoft Academic Search

The vestibular aqueduct (VA) and endolymphatic sac (ES) were examined by magnetic resonance imaging in eight patients (14 ears) with large VAs, and the results were compared with those obtained in five normal volunteers (10 ears). It was not possible to identify either the VA or ES in any of the control ears. However, in all the 14 ears with

T. Okumura; I. Honjo; H. Takahashi; A. Takagi; R. Azato

1996-01-01

99

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

100

Does a continuous local anaesthetic pain treatment after immediate tissue expander reconstruction in breast carcinoma patients more efficiently reduce acute postoperative pain - a prospective randomised study  

PubMed Central

Background Immediate breast reconstruction with an expander is a reasonable option for properly selected patients. After reconstruction, patients have severe postoperative pain, which responds poorly to opioids. Our aim was to evaluate if continuous wound infusion of a local anaesthetic into the surgical wound reduces postoperative pain, consumption of opioids and incidence of chronic pain compared to standard intravenous piritramide after primary breast reconstruction in breast carcinoma patients. Methods Altogether, 60 patients were enrolled in our study; one half in the group with wound infusion of a local anaesthetic, and the other half in the standard (piritramide) group. Parameters measured included: pain intensity (visual analogue scale), drug requirements, alertness, hospitalisation, side-effects and late complications. A p-value of?expander breast reconstruction, wound infusion of a local anaesthetic significantly reduces acute pain and enables reduced opioid consumption, resulting in less postoperative sedation and reduced need for antiemetic drugs. Wound infusion of a local anaesthetic reduces chronic pain. PMID:24433317

2014-01-01

101

Patient-Centered Imaging: Shared Decision Making for Cardiac Imaging Procedures with Exposure to Ionizing Radiation  

PubMed Central

Objective To identify key components of a radiation accountability framework fostering patient-centered imaging and shared decision-making in cardiac imaging. Background An NIH-NHLBI/NCI-sponsored symposium was held in November 2012 to address these issues. Methods Symposium participants, working in three 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. Results 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 ?3mSv is considered very low risk, not warranting extensive discussion or written consent. However, a protocol effective dose <20mSv 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. Conclusions 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; Dorbala, Sharmila; Garcia, Ernest V.; Gibbons, Raymond J.; Halliburton, Sandra S.; Hausleiter, Jörg; Heller, Gary V.; Jerome, Scott; Lesser, John R.; Fazel, Reza; Raff, Gilbert L.; Tilkemeier, Peter; Williams, Kim A.; Shaw, Leslee J.

2014-01-01

102

Telomere length of in vivo expanded CD4 + CD25 + regulatory T-cells is preserved in cancer patients  

Microsoft Academic Search

Purpose: CD4+CD25+ regulatory T-cells (Treg) are increased in the peripheral blood of cancer patients. It remains unclear whether this is due to redistribution or active proliferation. The latter would require the upregulation of telomerase activity, whose regulation also remains unknown for Treg. Experimental Design: Treg and CD4+CD25? T-cells were isolated from peripheral blood of cancer patients (n=23) and healthy age-matched

Dominik Wolf; Holger Rumpold; Christian Koppelstätter; Guenther A. Gastl; Michael Steurer; Gert Mayer; Eberhard Gunsilius; Herbert Tilg; Anna M. Wolf

2006-01-01

103

The role of functional imaging in the tumor patient.  

PubMed

Functional imaging studies complement structural magnetic resonance imaging (MRI) in the assessment of patients with brain tumor-associated focal epilepsy. (11)C-Methionine (MET) and (18) F-fluoro-ethyl-L-tyrosine (FET) are amino acid analogues that highlight metabolically active areas in positron emission tomography (PET). Ictal single photon emission computed tomography (SPECT) can provide information about perilesional areas of seizure onset and early propagation. Functional MRI (fMRI) and diffusion tensor imaging (DTI) allow noninvasive identification of potentially eloquent motor, sensory, and language cortical areas and pathways with an accuracy of 10-15 mm compared to electrocortical stimulation (ECS). Repetitive navigated transcranial magnetic stimulation (TMS) allows even more precise noninvasive delineation of primary motor cortex. Information from functional imaging studies helps in the planning of brain tumor biopsies, resections, and the planning of intracranial video-electroencephalography (EEG) studies. PMID:24328872

Wehner, Tim

2013-12-01

104

QUANTITATIVE T2? IMAGING IN PATIENTS WITH CLINICALLY ISOLATED SYNDROME  

PubMed Central

Objective T2? imaging has been shown to be sensitive to oxygen saturation changes in normal appearing white and grey matter (NAWM, NAGM) in patients with relapsing-remitting multiple sclerosis (RRMS). We aimed to explore the presence and extent of T2? changes in patients with a clinically isolated syndrome (CIS) and a possible association of T2? with conventional MRI and clinical outcomes. Material & methods Quantitative T2- and T2*-weighted images were acquired in 32 treatment-naive patients with a CIS within 3 months of presentation and 15 age-matched healthy controls (HC). Quantitative T2? values were determined in six regions of interest (ROIs). Results T2? values in CIS did not differ significantly from those in HC. Among patients, T2? values correlated positively with the T2 lesion volume (T2LV, r=0.34, p<0.05). T2? values of the frontal NAWM correlated with the T2LV (r=0.35, p<0.05) and T2 lesion count (r=0.4, p=0.02). Conclusion As opposed to RRMS, patients with CIS did not show T2? alterations compared to HC. However, the association between the T2LV and higher T2? values suggests that T2? reflects disease evolution. In CIS metabolic changes might be masked by compensatory mechanisms and become overt when disease progresses as has been shown for RRMS patients. PMID:22211987

Reitz, Liza Yamila; Inglese, Matilde; Fiehler, Jens; Finsterbusch, Jürgen; Holst, Brigitte; Heesen, Christoph; Martin, Roland; Schippling, Sven

2011-01-01

105

Expanded access to investigational drugs.  

PubMed

To the Editor: Darrow et al. (Jan. 15 issue)(1) highlight the challenges posed by expanded patient access to unapproved drugs, including an application process that may have been complicated by the time and complexity for physicians to complete the form currently used by the Food and Drug Administration (FDA) and multiple associated documents.(2) On February 4, 2015, the FDA published draft guidance on a streamlined process for individual-patient expanded-access submissions by physicians treating single patients with investigational drugs.(3) The process continues to protect patients while not undermining clinical-trial enrollment. Feedback from academia, physicians, patients, advocacy groups, and industry helped the . . . PMID:25839859

Lurie, Peter; Chan-Tack, Kirk M; Woodcock, Janet

2015-04-01

106

Expanded access to investigational drugs.  

PubMed

To the Editor: Darrow et al. (Jan. 15 issue)(1) highlight the challenges posed by expanded patient access to unapproved drugs, including an application process that may have been complicated by the time and complexity for physicians to complete the form currently used by the Food and Drug Administration (FDA) and multiple associated documents.(2) On February 4, 2015, the FDA published draft guidance on a streamlined process for individual-patient expanded-access submissions by physicians treating single patients with investigational drugs.(3) The process continues to protect patients while not undermining clinical-trial enrollment. Feedback from academia, physicians, patients, advocacy groups, and industry helped the . . . PMID:25839858

2015-04-01

107

Cardiac imaging in evaluating patients prone to sudden death  

PubMed Central

Identifying subjects who are at risk for SCD and stratifying them correctly into low or high-risk groups is the holy grail of Cardiology. While imaging shows a lot of promise, it is plagued by the fact that most SCD occurs in relatively healthy subjects, a massive group who would not ordinarily be subjected to imaging. Left ventricular ejection fraction (LVEF) currently is our primary parameter for risk stratification for sudden cardiac death but is a poor marker with low sensitivity and specificity. Current data shows that sophisticated imaging with techniques, mainly Cardiac magnetic resonance Imaging (CMR), have the potential to identify novel high-risk markers underlying SCD, beyond ejection fraction. Imaging seems to further refine risk in patients with low LVEF as well as in those with normal EF; this is a major strength of advanced imaging. Clinical application has been slow and not fully prime time. It is important to remember that while promising, imaging techniques including CMR, have not been tested in rigorous prospective studies and thus have not as yet replaced EF as the gatekeeper to ICD implantation. PMID:24568832

Tamene, Ashenafi; Tholakanahalli, Venkatakrishna N.; Chandrashekhar, Y.

2014-01-01

108

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. PMID:25610261

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

2013-01-01

109

Multiorgan dysfunctions in diabetic patients: the role of functional imaging.  

PubMed

Functional imaging plays a central role in the evaluation of some of the clinical problems faced by diabetic patients. In cardiovascular disease, myocardial perfusion imaging, particularly when complemented by gated SPECT, is a powerful tool not only for establishing the diagnosis of coronary artery disease, but also for providing prognostic information in both the general and diabetic populations. Although promising, its role in screening of asymptomatic diabetic patients is yet to be established, and its role as a potential 'one-stop shop' also needs further study. PET is currently the gold standard for viability assessment, and also provides prognostic data, but its widespread use is limited by cost and availability. Hybrid imaging with PET/CT is promising, and could revolutionise cardiac imaging by combining functional and anatomic information. In the investigation of the diabetic foot, labelled leukocyte imaging is the nuclear medicine test of choice to diagnose osteomyelitis. It is likely that SPECT/CT will further improve diagnostic accuracy, but more studies are needed. Combined leukocyte and bone marrow imaging is of value in distinguishing osteomyelitis from neuropathic osteoarthropathy in the diabetic foot; PET and PET/CT may also be of value in these cases, but their wider role is currently inconclusive. The value of bone scintigraphy in the diabetic foot, even as a screening test, is questionable. Functional imaging methods can also be employed in the evaluation of other diabetic complications, including the assessment of left ventricular function, renal scarring and gastric emptying, but these methods are not widely used in current clinical practice. PMID:19859045

Shah, S; Win, Z; Al-Nahhas, A

2009-09-01

110

The Expanding Role of Mitral Valve Repair in Triple Valve Operations: Contemporary North American Outcomes in 8,021 Patients  

PubMed Central

Background Although the operative risk of multivalve operations has historically been high, current outcomes are poorly understood. We sought to evaluate factors influencing contemporary results of triple-valve operations using The Society of Thoracic Surgeons Adult Cardiac Surgery Database. Methods Among patients undergoing combined mitral, aortic, and tricuspid valve (triple- valve) operations between 1993 and 2011, aortic valve repair patients were excluded and those having aortic valve replacement were analyzed according to whether they underwent repair vs replacement of the mitral valve (MV) and tricuspid valve (TV). Temporal trends in operative death and clinical outcomes were examined using unadjusted and adjusted analyses. Results A total of 8,021 triple-valve patients were studied. The median (25th percentile, 75th percentile) age was 67 years (59, 77 years), 4,809 (60%) were women, 4,488 (56%) had New York Heart Association class III to IV symptoms, and the mean (25th percentile, 75th percentile) ejection fraction was 50% (40%, 60%). MV repair was performed in 2,728 (34%) patients overall and increased over time from 13% (1993 to 1997) to 41% (2008 to 2011). TV repair was performed in 7,512 (94%) patients overall and increased over time from 86% (1993 to 1997) to 96% (2008 to 2011). Unadjusted operative mortality decreased from 17% in 1993 to 9% in 2011. Adjusted odds ratios (95% confidence intervals) of operative mortality were lower in those having MV repair (0.72 [0.61 to 0.85]), TV repair (0.64 [0.50 to 0.83]), and MV D TV repair (0.46 [0.34 to 0.63]) compared with those having replacements. Unadjusted and adjusted odds of stroke were similar between groups and not significant for all. Conclusions This large series demonstrates that surgical results of triple-valve operations have continued to improve during the past 18 years. MV and TV repair were associated with improvements in early survival. Although further study is required to understand late outcomes, these data suggest that broader efforts to perform MV repair instead of replacement in this high-risk patient population appear warranted. PMID:24680034

Suri, Rakesh M.; Thourani, Vinod H.; Englum, Brian R.; Rankin, J. Scott; Badhwar, Vinay; Svensson, Lars G.; Ailawadi, Gorav; Mack, Michael J.; He, Max; Brennan, J. Matthew; Schaff, Hartzell V.; Gammie, James S.

2015-01-01

111

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

112

268. CD19-Targeted Normal and CLL Patient T Cells Expanded with Beads Can Eradicate Systemic Tumors In Vivo  

Microsoft Academic Search

In order to conduct a clinical trial of adoptive therapy with genetically modified T cells in patients with CLL, we are investigating the feasibility of ex vivo T cell transduction and expansion using Xcyte™ Dynabeads® to generate sufficient numbers of biologically active tumor-reactive T cells. T cells are genetically modified to express 19-28z chimeric antigen receptor (CAR). The 19-28z CAR

J. Stefanski; R. Brentjens; D. Hollyman; M. Bonyhadi; M. Sadelain; I. Rivière

2006-01-01

113

IR imaging of blood circulation of patients with vascular disease  

NASA Astrophysics Data System (ADS)

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 in blood flow is revealed by temperature differences in areas of the extremities as well as other regions of the body. However, what is needed is an imaging technique that is relatively inexpensive and can reveal the blood flow in real time. The IR imaging can show detailed venous system and small tempearture changes associated with blood flow. Six patients with vascular diseases were tested in a clinic set up. Their legs and feet were imaged. We observed large temperature differences (cooling of more than 10° C) at the foot, especially toes. More valuable information were obtained from the temperature distribution maps. IR thermography is potentially a very valuable tool for medical application, especially for vascular diseases.

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

2004-04-01

114

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

115

Cardiac magnetic resonance imaging in patients with Fabry's disease.  

PubMed

Fabry's disease (FD) is a rare hereditary disorder caused by the loss of alpha galactosidase A activity leading to accumulation of glycosphingolipids in various organs including hypertrophy of the heart. Most reports on cardiac involvement in FD focus on the left ventricular hypertrophy (LVH) and its relation to diastolic function. However, recent studies demonstrated large subset of patients with FD and right ventricle (RV) hypertophy. The accurate depiction of RV volumes, function and mass is possible with cardiovascular magnetic resonance (CMR). The CMR study can be also used to identify typically localised regions of intramyocardial fibrosis (infero-lateral segments of the LV), which have been shown to be a marker of inefficacious response to enzyme replacement therapy. We present series of 8 patients with genetically confirmed FD who underwent CMR study. We demonstrated a typical concentric and diffuse pattern of LVH with RV involvement in patients with the most severe LVH without significant impact on RV function and volumes. We showed that myocardial fibrosis can be observed not only in LV but also in RV. In 2 patients FD coexisted with symptomatic coronary artery disease with evidence of subendocardial myocardial fibrosis typical for ischaemic origin in one patient. The CMR confirmation of the presence of FD in one patient at an early stage of the disease, before the onset of advanced hypertrophy or failure of other organs, supports the value of this imaging technique in differential diagnosis of concentric and diffuse LVH. PMID:20730727

Ma?ek, Lukasz A; Chojnowska, Lidia; Spiewak, Mateusz; K?opotowski, Mariusz; Mi?ko, Jolanta; Petryka, Joanna; Mi?osz, Barbara; Ruzy??o, Witold

2010-08-01

116

Cerebella segmentation on MR images of pediatric patients with medulloblastoma  

NASA Astrophysics Data System (ADS)

In this study, an automated method has been developed to identify the cerebellum from T1-weighted MR brain images of patients with medulloblastoma. A new objective function that is similar to Gibbs free energy in classic physics was defined; and the brain structure delineation was viewed as a process of minimizing Gibbs free energy. We used a rigid-body registration and an active contour (snake) method to minimize the Gibbs free energy in this study. The method was applied to 20 patient data sets to generate cerebellum images and volumetric results. The generated cerebellum images were compared with two manually drawn results. Strong correlations were found between the automatically and manually generated volumetric results, the correlation coefficients with each of manual results were 0.971 and 0.974, respectively. The average Jaccard similarities with each of two manual results were 0.89 and 0.88, respectively. The average Kappa indexes with each of two manual results were 0.94 and 0.93, respectively. These results showed this method was both robust and accurate for cerebellum segmentation. The method may be applied to various research and clinical investigation in which cerebellum segmentation and quantitative MR measurement of cerebellum are needed.

Shan, Zu Y.; Ji, Qing; Glass, John; Gajjar, Amar; Reddick, Wilburn E.

2005-04-01

117

Magnetization Transfer Imaging of Suicidal Patients with Major Depressive Disorder  

PubMed Central

Magnetization transfer imaging (MTI) provides a quantitative measure of the macromolecular structural integrity of brain tissue, as represented by magnetization transfer ratio (MTR). In this study, we utilized MTI to identify biophysical alterations in MDD patients with a history of suicide attempts relative to MDD patients without such history. The participants were 36 medication-free MDD patients, with (N = 17) and without (N = 19) a history of a suicide attempt, and 28 healthy controls matched for age and gender. Whole brain voxel-based analysis was used to compare MTR across three groups and to analyze correlations with symptom severity and illness duration. We identified decreased MTR in left inferior parietal lobule and right superior parietal lobule in suicide attempters relative to both non-attempters and controls. Non-attempters also showed significantly reduced MTR in left inferior parietal lobule relative to controls, as well as an MTR reduction in left cerebellum. These abnormalities were not correlated with symptom severity or illness duration. Depressed patients with a history of suicide attempt showed bilateral abnormalities in parietal cortex compared to nonsuicidal depressed patients and healthy controls. Parietal lobe abnormalities might cause attentional dysfunction and impaired decision making to increase risk for suicidal behavior in MDD. PMID:25853872

Chen, Ziqi; Zhang, Huawei; Jia, Zhiyun; Zhong, Jingjie; Huang, Xiaoqi; Du, Mingying; Chen, Lizhou; Kuang, Weihong; Sweeney, John A.; Gong, Qiyong

2015-01-01

118

Magnetization transfer imaging of suicidal patients with major depressive disorder.  

PubMed

Magnetization transfer imaging (MTI) provides a quantitative measure of the macromolecular structural integrity of brain tissue, as represented by magnetization transfer ratio (MTR). In this study, we utilized MTI to identify biophysical alterations in MDD patients with a history of suicide attempts relative to MDD patients without such history. The participants were 36 medication-free MDD patients, with (N = 17) and without (N = 19) a history of a suicide attempt, and 28 healthy controls matched for age and gender. Whole brain voxel-based analysis was used to compare MTR across three groups and to analyze correlations with symptom severity and illness duration. We identified decreased MTR in left inferior parietal lobule and right superior parietal lobule in suicide attempters relative to both non-attempters and controls. Non-attempters also showed significantly reduced MTR in left inferior parietal lobule relative to controls, as well as an MTR reduction in left cerebellum. These abnormalities were not correlated with symptom severity or illness duration. Depressed patients with a history of suicide attempt showed bilateral abnormalities in parietal cortex compared to nonsuicidal depressed patients and healthy controls. Parietal lobe abnormalities might cause attentional dysfunction and impaired decision making to increase risk for suicidal behavior in MDD. PMID:25853872

Chen, Ziqi; Zhang, Huawei; Jia, Zhiyun; Zhong, Jingjie; Huang, Xiaoqi; Du, Mingying; Chen, Lizhou; Kuang, Weihong; Sweeney, John A; Gong, Qiyong

2015-01-01

119

Patient specific tumor growth prediction using multimodal images.  

PubMed

Personalized tumor growth model is valuable in tumor staging and therapy planning. In this paper, we present a patient specific tumor growth model based on longitudinal multimodal imaging data including dual-phase CT and FDG-PET. The proposed Reaction-Advection-Diffusion model is capable of integrating cancerous cell proliferation, infiltration, metabolic rate and extracellular matrix biomechanical response. To bridge the model with multimodal imaging data, we introduce Intracellular Volume Fraction (ICVF) measured from dual-phase CT and Standardized Uptake Value (SUV) measured from FDG-PET into the model. The patient specific model parameters are estimated by fitting the model to the observation, which leads to an inverse problem formalized as a coupled Partial Differential Equations (PDE)-constrained optimization problem. The optimality system is derived and solved by the Finite Difference Method. The model was evaluated by comparing the predicted tumors with the observed tumors in terms of average surface distance (ASD), root mean square difference (RMSD) of the ICVF map, average ICVF difference (AICVFD) of tumor surface and tumor relative volume difference (RVD) on six patients with pathologically confirmed pancreatic neuroendocrine tumors. The ASD between the predicted tumor and the reference tumor was 2.4±0.5mm, the RMSD was 4.3±0.4%, the AICVFD was 2.6±0.6%, and the RVD was 7.7±1.3%. PMID:24607911

Liu, Yixun; Sadowski, Samira M; Weisbrod, Allison B; Kebebew, Electron; Summers, Ronald M; Yao, Jianhua

2014-04-01

120

CDAWeb and SSCWeb: Expanding Correlative Sun-Earth-Connections Science Services in the New Era of IMAGE and Cluster  

NASA Astrophysics Data System (ADS)

The Coordinated Data Analysis [Workshop] Web service (CDAWeb) supports graphical and data retrieval access to a uniquely broad and still growing database of multi-mission Sun-Earth-Connections (SEC) data. SSCWeb serves satellite orbits and various multi-mission conjunctions queries. By May 2001, CDAWeb will be serving public data from all IMAGE instruments and Cluster Summary Parameters, as well as Cluster Prime Parameters to authorized Cluster science investigators. These systems make current data quickly accessible to a wide research community and immediately available in the context of simultaneous data from almost all other current space physics missions. These systems are first working prototypes for delivering the class of integrated, multi-mission data view essential to the programs like Living with a Star (LWS). These systems' databases, capabilities, and usage continue to grow. CDAWeb has served 150,000 separate plots and listings in the last year alone, SSCWeb 26,000 listings, query results and plots. CDAWeb now has over 1450 days (4 years) with data from more 100 data sets available for every day. Over the last year, CDAWeb has been extended to 350+ GBytes and added new datasets from Wind, Polar and IMP-8, as well as ongoing flows of data from many other missions. CDAWeb remains supported by three mirror sites (in Germany-MPE, England-RAL and Japan-ISAS) as well as by the primary site at Goddard. ASCII listing and file retrieval services have been extended to include compressed (gzip) and multiple-file combined (tar) "one-keystroke" retrievals. Supported by the NASA Office of Space Science, CDAWeb and SSCWeb are joint efforts of the NASA GSFC Space Physics Data Facility (SPDF) and the National Space Science Data Center (NSSDC). These services are only possible in turn by data flows from various project data facilities and the work of the instrument science teams on the many missions now supported.

McGuire, R. E.; Candey, R. M.; Fung, S. F.; Green, J. L.; Kessel, R. L.; Kovalick, T. J.

2001-05-01

121

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

122

Surgical transposition of the ovaries: Imaging findings in 14 patients  

SciTech Connect

Pelvic radiation therapy for cervical or vaginal cancer often leads to ovarian failure. To remove the ovaries from the radiation portal and preserve their function, they can be transposed to the lateral abdomen. Serial imaging studies in 14 patients who had undergone ovarian transposition (five bilateral, nine unilateral) were reviewed. Images obtained included 32 CT scans, 20 sonograms, and one MR image. Most transposed ovaries were located along the paracolic gutters near the iliac crests, creating an extrinsic mass effect on adjacent bowel. Detection of surgical clips on the ovary on CT scans allowed confident recognition of all 19 transposed ovaries. Cysts in the transposed ovaries, noted on most imaging studies, did not correlate with complications of pain or hormonal dysfunction. In one case, a large physiologic cyst in a transposed ovary distorted the cecum and was mistaken for a mucocele of the appendix. In another case, a large ovarian cyst was thought to be tumor recurrence or a lymphocele. These findings indicate that although the transposed ovaries can be recognized on CT scans by the surgical clips attached to the ovaries, the appearance of the ovary does not predict reliably the development of complications.

Kier, R.; Chambers, S.K. (Yale Univ. School of Medicine, New Haven, CT (USA))

1989-11-01

123

Mitochondrial neurogastrointestinal encephalomyopathy: imaging and clinical findings in three patients.  

PubMed

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare multisystemic autosomal recessive disorder characterized by ptosis, gastrointestinal dysmotility, cachexia, peripheral neuropathy, and leukoencephalopathy. We aimed to raise awareness in radiologists regarding this difficult-to-diagnose syndrome, which occurs in the presence of coexistent gastrointestinal dysmotility, cachexia, and neurologic manifestations. We report imaging and clinical findings of three patients with MNGIE. Our findings indicate that early diagnosis of the disease, together with the timely treatment of acute intercurrent illnesses, may retard the progression of MNGIE. PMID:23302282

Çoban, Gökçen; Göktürk, Sava?; Yildirim, Erkan; Çal??kan, Zuhal; Horasanli, Bahriye; Akça, Hatice Aysun

2013-01-01

124

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.

125

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

126

Patient and Family Impact of Pediatric Genitourinary Diagnostic Imaging Tests  

PubMed Central

Purpose The impact of diagnostic genito-urinary imaging (GUI) on patients and families is poorly understood. We study sought to measure patient and family reaction to commonly performed GUI studies, using a standardized measurement tool. Methods We surveyed families undergoing GUI (renal ultrasound (RUS), voiding cystourethrography (VCUG), radionuclide cystogram (RNC), static renal scintigraphy (DMSA), and diuretic renal scintigraphy (MAG3)), using a Likert-scaled 11-item survey to assess impact across four domains (pain, anxiety, time, satisfaction). Survey scores were analyzed using ANOVA and linear regression. Results 263 families were surveyed (61 RUS, 52 VCUG, 55 RNC, 47 MAG3, 48 DMSA). Mean age was 2.1 years. 45% were male. 77% were white. Patient age, gender, and prior GUI experience varied by study type. Study type was significantly associated with both total and weighted scores on the GUI survey (both p<0.0001). RUS was better and MAG3 was worse than VCUG, RNC, and DMSA, which did not differ from each other. Other factors associated with worse total scores included patient age 1–3 years (p<0.001) and non-white race (p=0.04). Gender, prior testing history, wait time, and parent education were not associated with total scores. In the multivariate model, RUS remained the best and MAG3 the worst (p<0.0001). Compared directly, DMSA and VCUG total scores did not differ (p=0.59). Conclusion There are significant differences among GUI studies regarding the patient/family experience, but there was no overall difference between DMSA and VCUG. These findings may be useful to aid decision-making when considering GUI for children. PMID:22910271

Nelson, Caleb P.; Chow, Jeanne S.; Rosoklija, Ilina; Ziniel, Sonja; Routh, Jonathan C.; Cilento, Barley G.

2013-01-01

127

Protecting patient privacy against unauthorized release of medical images in a group communication environment  

E-print Network

on privacy of patients' information. Constant efforts are being made to provide security solutions [2Protecting patient privacy against unauthorized release of medical images in a group communication identify and study an important patient privacy protection problem related to medical images. Following

Poovendran, Radha

128

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

129

Multislice CT Scans in Patients on Extracorporeal Membrane Oxygenation: Emphasis on Hemodynamic Changes and Imaging Pitfalls  

PubMed Central

This pictorial review provides the principles of extracorporeal membrane oxygenation (ECMO) support and associated CT imaging features with emphasis on the hemodynamic changes and possible imaging pitfalls encountered. It is important that radiologists in ECMO centers apply well-designed imaging protocols and familiarize themselves with post-contrast CT imaging findings in patients on ECMO. PMID:24843236

Liu, Kao-Lang; Wang, Yu-Feng; Chang, Yeun-Chung; Huang, Shu-Chien; Chen, Shyh-Jye; Tsang, Yuk-Ming

2014-01-01

130

89Zr-huJ591 immuno-PET imaging in patients with advanced metastatic prostate cancer  

PubMed Central

Purpose Given the bone tropism of prostate cancer, conventional imaging modalities poorly identify or quantify metastatic disease. 89Zr-huJ591 positron emission tomography (PET) imaging was performed in patients with metastatic prostate cancer to analyze and validate this as an imaging biomarker for metastatic disease. The purpose of this initial study was to assess safety, biodistribution, normal organ dosimetry, and optimal imaging time post-injection for lesion detection. Methods Ten patients with metastatic prostate cancer received 5 mCi of 89Zr-huJ591. Four whole-body scans with multiple whole-body count rate measurements and serum activity concentration measurements were obtained in all patients. Biodistribution, clearance, and lesion uptake by 89Zr-huJ591 immuno-PET imaging was analyzed and dosimetry was estimated using MIRD techniques. Initial assessment of lesion targeting of 89Zr-huJ591 was done. Optimal time for imaging post-injection was determined. Results The dose was well tolerated with mild chills and rigors seen in two patients. The clearance of 89Zr-huJ591 from serum was bi-exponential with biological half-lives of 7 ± 4.5 h (range 1.1–14 h) and 62 ± 13 h (range 51–89 h) for initial rapid and later slow phase. Whole-body biological clearance was 219 ± 48 h (range 153–317 h). The mean whole-body and liver residence time was 78.7 and 25.6 h, respectively. Dosimetric estimates to critical organs included liver 7.7 ± 1.5 cGy/mCi, renal cortex 3.5 ± 0.4 cGy/mCi, and bone marrow 1.2 ± 0.2 cGy/mCi. Optimal time for patient imaging after injection was 7 ± 1 days. Lesion targeting of bone or soft tissue was seen in all patients. Biopsies were performed in 8 patients for a total 12 lesions, all of which were histologically confirmed as metastatic prostate cancer. One biopsy-proven lesion was not positive on 89Zr-huJ591, while the remaining 11 lesions were 89Zr-huJ591 positive. Two biopsy-positive nodal lesions were noted only on 89Zr-huJ591 study, while the conventional imaging modality was negative. Conclusion 89Zr-huJ591 PET imaging of prostate-specific membrane antigen expression is safe and shows good localization of disease in prostate cancer patients. Liver is the critical organ for dosimetry, and 7 ± 1 days is the optimal imaging time. A larger study is underway to determine lesion detection in an expanded cohort of patients with metastatic prostate cancer. PMID:25143071

O’Donoghue, Joseph A.; Beylergil, Volkan; Lyashchenko, Serge; Ruan, Shutian; Solomon, Stephen B.; Durack, Jeremy C.; Carrasquillo, Jorge A.; Lefkowitz, Robert A.; Gonen, Mithat; Lewis, Jason S.; Holland, Jason P.; Cheal, Sarah M.; Reuter, Victor E.; Osborne, Joseph R.; Loda, Massimo F.; Smith-Jones, Peter M.; Weber, Wolfgang A.; Bander, Neil H.; Scher, Howard I.; Morris, Michael J.; Larson, Steven M.

2015-01-01

131

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

132

Computer-Based Assessment of Body Image Distortion in Anorexia Nervosa Patients  

E-print Network

Abstract. A computer-based method for the assessment of body image distortions in anorexia nervosa and other eating-disordered patients is presented. At the core of the method is a realistic pictorial simulation of lifelike weight-changes, applied to a real source image of the patient. The patients, using a graphical user interface, adjust their body shapes until they meet their self-perceived appearance. Measuring the extent of virtual fattening or slimming of a body with respect to its real shape and size, allows direct, quantitative evaluation of the cognitive distortion in body image. In a preliminary experiment involving 20 anorexia-nervosa patients, 70 % of the subjects chose an image with simulated visual weight gain of about 20 % as their “real ” body image. None of them recognized the original body image, thus demonstrating the quality of the transformed images. The method presented can be applied in the research, diagnosis, evaluation and treatment of eating disorders. 1

Daniel Harari; Miriam Furst; Nahum Kiryati; Michael Davidson

133

Treatment of acutely ruptured wide-necked intracranial aneurysms using self-expanding stent  

PubMed Central

Objectives: To evaluate the effectiveness and safety of self-expanding stent in treatment of acutely ruptured wide-necked intracranial aneurysms in the acute stage. Method: Treatment of 38 patients with self-expanding stent was retrospectively analyzed. Results: From January 2009 to May 2014, a total of 38 patients with 44 acutely ruptured wide-necked intracranial aneurysms were embolized with self-expanding stents at our center. Immediate post-operative imaging demonstrated that the aneurysms were densely packed in 17 patients, subtotally embolized in 2 patients, and subtotally embolized with residual aneurysm necks in 19 patients. At discharge, the patients were assessed for prognosis and the results revealed nerve dysfunction in 3 patients (7.9%), coma in 6 patients (15.8%), hospital death in 1 case (2.6%). Twenty-eight (73.7%) patients were asymptomatic at discharge. Ten of the 38 patients were followed up by angiography for a period of 3.7 months on average, which showed complete occlusion in 9 patients (90%), remnant aneurysm necks in 1 patient (10%), and no recanalization was observed in all the followed-up patients. Stent related complications also were recorded. Conclusion: Stent-assisted coiling is effective in treating acutely ruptured wide-necked intracranial aneurysms. Angiographic investigation and clinical follow-up is needed for evaluation of long-term clinical outcomes. PMID:25785122

Li, Hui; Guan, Jinqun; Liu, Jianfeng; Hou, Kai; Zhao, Di; Wu, Guobiao; Xu, Lifeng; Liu, Linlin

2015-01-01

134

Quantification of radiographic image quality based on patient anatomical contrast-to-noise ratio: a preliminary study with chest images  

NASA Astrophysics Data System (ADS)

The quality of a digital radiograph for diagnostic imaging depends on many factors, such as the capture system DQE and MTF, the exposure technique factors, the patient anatomy, and the particular image processing method and processing parameters used. Therefore, the overall image quality as perceived by the radiologists depends on many factors. This work explores objective image quality metrics directly from display-ready patient images. A preliminary study was conducted based on a multi-frequency analysis of anatomy contrast and noise magnitude from 250 computed radiography (CR) chest radiographs (150 PA, 50 AP captured with anti-scatter grids, and 50 AP without grids). The contrast and noise values were evaluated in different sub-bands separately according to their frequency properties. Contrast-Noise ratio (CNR) was calculated, the results correlated well with the human observers' overall impression on the images captured with and without grids.

Lin, Yuan; Wang, Xiaohui; Sehnert, William J.; Foos, David H.; Barski, Lori; Samei, Ehsan

2010-02-01

135

Managing Body Image Difficulties of Adult Cancer Patients: Lessons from Available Research  

PubMed Central

Background Body image is a critical psychosocial issue for cancer patients as they often undergo significant changes to appearance and functioning. In this review article, our primary purpose was to identify empirically-supported approaches to treat body image difficulties of adult cancer patients that can be incorporated into high-quality comprehensive cancer care. Methods We provided an overview of theoretical models of body image relevant to cancer patients, and presented findings from published literature on body image and cancer from 2003–2013. We integrated these data with information from the patient-doctor communication literature to delineate a practical approach for assessing and treating body image concerns of adult cancer patients. Results Body image difficulties were found across patients with diverse cancer sites, and were most prevalent in the immediate postoperative and treatment period. Age, body mass index, and specific cancer treatments have been identified as potential risk factors for body image disturbance in cancer patients. Current evidence supports the use of time-limited cognitive-behavioral therapy interventions for addressing these difficulties. Other intervention strategies also show promise but require further study. We identified potential indicators of body image difficulties to alert healthcare professionals when to refer patients for psychosocial care, and proposed a framework for approaching conversations about body image that can be used by the oncologic treatment team. Conclusions Body image issues affect a wide array of cancer patients. Providers can use available evidence combined with information from the healthcare communication literature to develop practical strategies for treating body image concerns of cancer patients. PMID:24895287

Fingeret, Michelle Cororve; Teo, Irene; Epner, Daniel E.

2013-01-01

136

Integrated multimedia electronic patient record and graph-based image information for cerebral tumors.  

PubMed

Current electronic patient record (EPR) implementations do not incorporate medical images, nor structural information extracted from them, despite images increasing role for diagnosis. This paper presents an integration framework into EPRs of anatomical and pathological knowledge extracted from segmented magnetic resonance imaging (MRI), applying a graph of representation for anatomical and functional information for individual patients. Focusing on cerebral tumors examination and patient follow-up, multimedia EPRs were created and evaluated through a 3D navigation application, developed with open-source libraries and standards. Results suggest that the enhanced clinical information scheme could lead to original changes in the way medical experts utilize image-based information. PMID:18325489

Puentes, John; Batrancourt, Bénédicte; Atif, Jamal; Angelini, Elsa; Lecornu, Laurent; Zemirline, Abdelhamid; Bloch, Isabelle; Coatrieux, Gouenou; Roux, Christian

2008-04-01

137

Body image among eating disorder patients with disabilities: a review of published case studies.  

PubMed

While individual cases of eating disorder (ED) patients with disabilities have been reported, there has been little synthesis of their experiences of body image and thin idealization. This study reviews 19 published clinical reports of ED patients with sensory, mobility-related, or intellectual disabilities and evaluates the extent to which their experiences align with or challenge current conceptions of body image in ED. ED patients with visual impairment reported a profound disturbance of body image, perceived intersubjectively and through tactile sensations. Reducing dependence in mobility was an important motivation to control body size for ED patients with mobility-related disabilities. ED as a way of coping with and compensating for the psychosocial consequences of disability was a recurrent theme for patients across a range of disabilities. These experiential accounts of ED patients with disabilities broaden current understandings of body image to include touch and kinaesthetic awareness, intersubjective dynamics, and perceptions of normalcy. PMID:24958662

Cicmil, Nela; Eli, Karin

2014-06-01

138

Changes in the surgical management of patients with breast carcinoma based on preoperative magnetic resonance imaging  

Microsoft Academic Search

BACKGROUND. Breast magnetic resonance imaging (MRI) is a developing technique for the evaluation of patients with primary breast carcinoma. The authors assessed the impact of preoperative breast MRI on surgical management. METHODS. The current study was a retrospective review of 267 patients with primary breast tumors who had MRI studies prior to undergoing definitive surgery. RESULTS. Two hundred sixty-seven patients

Isabelle Bedrosian; Rosemarie Mick; Susan G. Orel; Mitchell Schnall; Carol Reynolds; Francis R. Spitz; Linda S. Callans; Gordon P. Buzby; Ernest F. Rosato; Douglas L. Fraker; Brian J. Czerniecki

2003-01-01

139

Developing a Theoretical Framework to Illustrate Associations Among Patient Satisfaction, Body Image and Quality of Life for Women Undergoing Breast Reconstruction  

PubMed Central

Within the field of breast reconstruction there is increasing focus on patient-reported outcomes related to satisfaction, body image, and quality of life. These outcomes are deemed highly relevant because the primary goal of breast reconstruction is to recreate the appearance of a breast (or breasts) that is satisfying to the patient. Prominent researchers have suggested the need to develop improved standards for outcome evaluation which can ultimately benefit patients as well as physicians. The purpose of this article is to summarize key findings in the area of patient-reported outcomes for breast reconstruction and introduce a theoretical framework for advancing research in this field. We conducted an extensive literature review of outcome studies for breast reconstruction focusing on patient-reported results. We developed a theoretical framework illustrating core patient-reported outcomes related to breast reconstruction and factors associated with these outcomes. Our theoretical model highlights domains and distinguishing features of patient satisfaction, body image, and quality of life outcomes for women undergoing breast reconstruction. This model further identifies a broad range of variables (e.g., historical/premorbid influences, disease and treatment-related factors) that have been found to influence patient-reported outcomes and need to be taken into consideration when designing future research in this area. Additional attention is given to examining the relationship between patient reported outcomes and outside evaluation of breast reconstruction. Our proposed theoretical framework suggests key opportunities to expand research in this area with the goal of optimizing body image adjustment, satisfaction, and psychosocial outcomes for the individual patient. PMID:23380309

Fingeret, Michelle Cororve; Nipomnick, Summer; Crosby, Melissa A.; Reece, Gregory P.

2013-01-01

140

Relationships between patient size, dose and image noise under automatic tube current modulation systems.  

PubMed

Automatic tube current modulation (ATCM) systems are now used for the majority of CT scans. The principles of ATCM operation are different in CT scanners from different manufacturers. Toshiba and GE scanners base the current modulation on a target noise setting, while Philips and Siemens scanners use reference image and reference mAs concepts respectively. Knowledge of the relationships between patient size, dose and image noise are important for CT patient dose optimisation. In this study, the CT patient doses were surveyed for 14 CT scanners from four different CT scanner manufacturers. The patient cross sectional area, the tube current modulation and the image noise from the CT images were analysed using in-house software. The Toshiba and GE scanner results showed that noise levels are relatively constant but tube currents are dependent on patient size. As a result of this there is a wide range in tube current values across different patient sizes, and doses for large patients are significantly higher in these scanners. In contrast, in the Philips and Siemens scanners, tube currents are less dependent on patient size, the range in tube current is narrower, and the doses for larger patients are not as high. Image noise is more dependent on the patient size. PMID:24334678

Sookpeng, S; Martin, C J; Gentle, D J; Lopez-Gonzalez, M R

2014-03-01

141

A Computer-Based Method for the Assessment of Body Image Distortions in Anorexia Nervosa Patients  

E-print Network

A computer-based method for the assessment of body image distortions in anorexia nervosa and other eating-disordered patients is presented. At the core of the method is a realistic pictorial simulation of lifelike weight-changes, applied to a real source image of the patient. The patients, using a graphical user interface, adjust their body shapes until they meet their self-perceived appearance. Measuring the extent of virtual fattening or slimming of a body with respect to its real shape and size, allows direct, quantitative evaluation of the cognitive distortion in body image. In a preliminary experiment involving 33 anorexia-nervosa patients, 70% of the subjects chose an image with simulated visual weight gain of between 8% and 16% as their "real" body image, while only one of them recognized the original body image. In a second experiment involving 30 healthy participants, the quality of the weight modified images was evaluated by pairwise selection trials. Over a weight change range of-16% to +28%, in about 30% of the trials, artificially modified images were mistakenly taken as "original" images, thus demonstrating the quality of the artificial images. The method presented is currently in a clinical validation phase, towards application in the research, diagnosis, evaluation and treatment of eating disorders.

Daniel Harari; Daniel Harari; Miriam Furst; Miriam Furst; Nahum Kiryati; Nahum Kiryati; Asaf Caspi; Asaf Caspi; Michael Davidson; Michael Davidson

2001-01-01

142

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

143

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

144

Magnetic resonance imaging in patients with unstable angina: comparison with acute myocardial infarction and normals  

SciTech Connect

The role of magnetic resonance imaging in characterizing normal, ischemic and infarcted segments of myocardium was examined in 8 patients with unstable angina, 11 patients with acute myocardial infarction, and 7 patients with stable angina. Eleven normal volunteers were imaged for comparison. Myocardial segments in short axis magnetic resonance images were classified as normal or abnormal on the basis of perfusion changes observed in thallium-201 images in 22 patients and according to the electrocariographic localization of infarction in 4 patients. T2 relaxation time was measured in 57 myocardial segments with abnormal perfusion (24 with reversible and 33 with irreversible perfusion changes) and in 25 normally perfused segments. T2 measurements in normally perfused segments of patients with acute myocardial infarction, unstable angina and stable angina were within normal range derived from T2 measurements in 48 myocardial segments of 11 normal volunteers (42 +/- 10 ms). T2 in abnormal myocardial segments of patients with stable angina also was not significantly different from normal. T2 of abnormal segments in patients with unstable angina (64 +/- 14 in reversibly ischemic and 67 +/- 21 in the irreversibly ischemic segments) was prolonged when compared to normal (p less than 0.0001) and was not significantly different from T2 in abnormal segments of patients with acute myocardial infarction (62 +/- 18 for reversibly and 66 +/- 11 for irreversibly ischemic segments). The data indicate that T2 prolongation is not specific for acute myocardial infarction and may be observed in abnormally perfused segments of patients with unstable angina.

Ahmad, M.; Johnson, R.F. Jr.; Fawcett, H.D.; Schreiber, M.H.

1988-09-01

145

Exercise thallium-201 imaging for risk stratification of elderly patients with coronary artery disease  

SciTech Connect

Although coronary artery disease (CAD) may be asymptomatic, it is the most common cause of death in elderly patients in the U.S. This study examined the prognosis of 449 patients with a mean age of 65 years using exercise thallium-201 imaging. At a follow-up of 25 months, 45 patients underwent coronary artery revascularization, 8 died of cardiac causes and 10 had nonfatal acute myocardial infarctions (AMIs). Thus, the total of patients with ''hard'' events was 18. The events included 12 of 276 patients with atypical or non-anginal symptoms versus 6 of 128 with typical angina (p = not significant); 7 of 51 patients (14%) with Q-wave AMI versus 11 of 353 (3%) without Q-wave AMI (p less than 0.001); 1 of 183 patients (1%) with normal versus 17 of 221 (8%) with abnormal exercise thallium-201 images (p less than 0.002); 10 of 76 patients (13%) with multi vessel thallium-201 abnormality vs 8 of 328 (2%) with no or 1-vessel thallium-201 abnormality (p less than 0.001) and 10 of 96 patients (10%) with greater than or equal to 3 abnormal segments by thallium-201 imaging (total segments = 9) versus 8 of 308 patients with no or less than 3 abnormal segments (p less than 0.001). The number of segments with thallium-201 defects was 1 +/- 2 patients without and 3 +/- 2 in patients with hard events (p less than 0.002).

Iskandrian, A.S.; Heo, J.; Decoskey, D.; Askenase, A.; Segal, B.L.

1988-02-01

146

Analysis of complications after EUS-FNA in patients with obstructive jaundice and drained with plastic biliary stents or self-expandable metal stent (SEMS): do complications differ between the type of stent?  

PubMed Central

Background and aims The standard of care for relieving malignant obstructive jaundice is endoscopic biliary stenting. There is debate on use of plastic biliary stents vs. self-expanding metal stents (SEMS) for biliary decompression. While the latter is more expensive, it tends to have a longer patency. Endoscopic ultrasound-fine needle aspiration (EUS-FNA) can be performed after biliary decompression for diagnostic and staging purposes. This retrospective study compares the complications of EUS-FNA in patients drained with plastic stents vs. SEMS. Materials and methods Seventy-six patients underwent EUS-FNA after biliary stenting. 31 patients received plastic stents and 45 patients received SE MS. All 76 patients underwent EUS-FNA by dedicated pancreatico-biliary endoscopists. All immediate complications within 48 hours of the EUS-FNA were recorded. Complication rates were statistically compared between patients with plastic stents vs. SEMS. Results A total of 76 patients with a mean age of 64.3 years were collected and analyzed retrospectively. 31 patients underwent plastic stenting and 45 patients underwent SE MS placement for biliary decompression for head of pancreas masses. A total of 4/31 patients had complications in the plastic stent group while 0/45 of patients had complications in the SE MS group (p=0.025). The complications in the plastic stent group were abdominal pain (n=2) and cholangitis (n=2). Conclusion This study suggests that EUS-FNA in patients who underwent biliary decompression with a plastic stent had significantly more complications than patients who underwent placement of a SEMS. We hypothesize that the smaller caliber biliary stent is more likely to occlude after FNA secondary to bleeding and/or edema. PMID:24498529

Rude, Katie; Wang, Andrew; Sauer, Bryan; White, Grace E; Kahaleh, Michel; Shami, Vanessa M

2013-01-01

147

Imaging Surveillance of Patients with Breast Cancer after Primary Treatment: Current Recommendations  

PubMed Central

Women who have been treated for breast cancer are at risk for second breast cancers, such as ipsilateral recurrence or contralateral metachronous breast cancer. As the number of breast cancer survivors increases, interest in patient management and surveillance after treatment has also increased. However, post-treatment surveillance programs for patients with breast cancer have not been firmly established. In this review, we focus on the imaging modalities that have been used in post-treatment surveillance for patients with breast cancer, such as mammography, ultrasonography, magnetic resonance imaging, and positron emission tomography, the effectiveness of each modality for detecting recurrence, and how they can be applied to manage patients. PMID:25741186

Yoon, Jung Hyun; Kim, Eun-Kyung; Moon, Hee Jung

2015-01-01

148

Patient-blaming and representation of risk factors in breast cancer images.  

PubMed

Media coverage of some cancers in the past often equated cancer with a death sentence. Breast cancer coverage in 1990s magazines, however, has become less fatalistic, more frequent, and discusses a broader range of issues than before. This study examined whether the visual images accompanying magazine articles about breast cancer have also evolved. We used Goffman's (1976) rituals of subordination to measure patient-blaming and subordinating, disempowering images. We also analyzed race/ethnicity, body type, and age of females in the images to gauge whether these demographic risk factors were represented in a random sample of images from nine magazines over a 30-year period. Magazines analyzed represented three genres-women's magazines, fashion/beauty, and general news. Findings suggest that patient-blaming images have decreased in some categories and women portrayed are slightly more representative of risk factors of age and race/ethnicity. Magazine images tended to reinforce stereotyped portrayals of femininity to the detriment of cancer patients. Fashion/beauty magazines, aimed at younger women, were most likely to portray breast cancer images in stereotyped, patient-blaming ways, with the least representative images of risk factors. The social construction of feminine beauty seems to overpower accuracy in creating these images. PMID:11289686

Andsager, J L; Hust, S J; Powers, A

2000-01-01

149

Dual source CT (DSCT) imaging of obese patients: evaluation of CT number accuracy, uniformity, and noise  

NASA Astrophysics Data System (ADS)

Obese patients present challenges in obtaining sufficient x-ray exposure over reasonable time periods for acceptable CT image quality. To overcome this limitation, the exposure can be divided between two x-ray sources using a dualsource (DS) CT system. However, cross-scatter issues in DS CT may also compromise image quality. We evaluated a DS CT system optimized for imaging obese patients, comparing the CT number accuracy and uniformity to the same images obtained with a single-source (SS) acquisition. The imaging modes were compared using both solid cylindrical PMMA phantoms and a semi-anthropomorphic thorax phantom fitted with extension rings to simulate different size patients. Clinical protocols were used and CTDIvol and kVp were held constant between SS and DS modes. Results demonstrated good agreement in CT number between SS and DS modes in CT number, with the DS mode showing better axial uniformity for the largest phantoms.

Walz-Flannigan, A.; Schmidt, B.,; Apel, A.; Eusemann, C.; Yu, L.; McCollough, C. H.

2009-02-01

150

Incidental parenchymal magnetic resonance imaging findings in the brains of patients with neurofibromatosis type 2?  

PubMed Central

Purpose Whereas T2 hyperintensities known as NF-associated bright spots are well described in patients with neurofibromatosis type I (NF-1), there is a paucity of data on incidental findings in patients with neurofibromatosis type II (NF-2). We aim to characterize unexplained imaging findings in the brains of patients with NF-2. Materials and methods This study is retrospective, HIPAA-compliant and approved by the institutional review board. 34 patients with NF-2 underwent brain magnetic resonance imaging (MRI) between January 2000 and December 2012. T2 and T1-weighted imaging characteristics, diffusion weighted imaging (DWI) characteristics, and enhancement patterns were analyzed by visual inspection. Clinical information at time of imaging was available for all patients. Neuropathologic data was available for one patient. Results We found unexplained T2 hyperintensities present on initial imaging in 23/34 patients (67%). Of the 23 patients with unexplained MRI findings, 15 (65%) had wedge-shaped T2 hyperintensities in the subcortical white matter extending to the cortex suggestive of a cortical dysplasia. 3 additional cases (17%) had a lesion within the cerebellum suggestive of a neuronal migration anomaly. In one patient where the MRI was suggestive of focal cortical dysplasia, histopathologic analysis revealed dysplastic glial foci without other alterations of cortical architecture or other cytologic abnormalities. Conclusion Unexplained T2 hyperintensities occur frequently in patients with NF-2. While they may not be the NF-2 equivalent of NF-associated bright spots seen in NF-1, some of these T2 hyperintensities in patients with NF-2 may represent underlying disorders of neuronal migration. Further studies are needed to validate our findings. PMID:24501699

Vargas, Wendy S.; Heier, Linda A.; Rodriguez, Fausto; Bergner, Amanda; Yohay, Kaleb

2014-01-01

151

Prospective comparative study of ability of MR imaging and other imaging modalities to localize tumors in patients with Zollinger-Ellison syndrome  

Microsoft Academic Search

The role of magnetic resonance (MR) imaging in patients with pancreatic endocrine tumors such as Zollinger-Ellison syndrome (ZES) is controversial. In the present study we have examined the ability of current MR imaging compared with other imaging modalities, to localize gastrinomas in 43 patients with ZES. All results were subsequently assessed at exploratory laparotomy (N=34) or by liver biopsy (N=9).

Joseph R. Pisegna; John L. Doppman; Jeffrey A. Norton; David C. Metz; Robert T. Jensen

1993-01-01

152

Upper extremity peripheral neuropathies: role and impact of MR imaging on patient management  

Microsoft Academic Search

To investigate the role of MR imaging (MRI) in the evaluation of peripheral nerve lesions of the upper extremities and to\\u000a assess its impact on the patient management. Fifty-one patients with clinical evidence of radial, median, and\\/or ulnar nerve\\u000a lesions and unclear or ambiguous clinical findings had MRI of the upper extremity at 1.5 T. MR images and clinical data were

Gustav Andreisek; Doris Burg; Ansgar Studer; Dominik Weishaupt

2008-01-01

153

Intraoperative gamma imaging of axillary sentinel lymph nodes in breast cancer patients.  

PubMed

Sentinel lymph node (SLN) biopsy is now standard practice in the management of many breast cancer patients. Localization protocols vary in complexity and rates of success. The least complex involve only intraoperative gamma counting of radiotracer uptake or intraoperative visualization of blue-dye uptake; the most complex involve preoperative gamma imaging, intraoperative counting and intraoperative dye visualization. Intraoperative gamma imaging may improve some protocols. This study was conducted to obtain preliminary experience and information regarding intraoperative imaging. Sixteen patients were enrolled: 8 in a protocol that included intraoperative counting and dye visualization (probe/dye), 8 in a protocol that involved intraoperative imaging, counting and dye visualization (camera/probe/dye). Preoperative imaging of all 16 patients was performed using a GE 500 gamma camera with a LEAP collimator (300 cpm/muCi). The results of this imaging were not, however, given to the surgeon until the surgeon had completed the procedures required for the study. A Care Wise C-Trak probe was used for intraoperative counting. A Gamma Medica Inc. GammaCAM/OR (12.5 x 12.5 cm FOV) with a LEHR collimator (135 cpm/muCi) was used for intraoperative imaging. Times from start of surgery to external detection of a radioactive focus and to completion of excision of SLNs were recorded. Foci were detected preoperatively via imaging in 16/16 patients. Intraoperative external detection using the probe was accomplished in less than 4 min (mean = 1.5 min) in 15/16 patients, and via intraoperative imaging in 6/8 patients. The average time for completion of excision of nodes was 19 min for probe/dye and 28 min for camera/probe/dye. In one probe/dye case, review of the preoperative images prompted the surgeon to resume axillary dissection and remove one additional SLN. PMID:17646000

Aarsvod, John N; Greene, Carmen M; Mintzer, Robert A; Grant, Sandra F; Styblo, Toncred M; Alazraki, Naomi P; Patt, Bradley E; Caravaglia, Gina M; Li, Joshua; Iwanczyk, Jan S

2006-01-01

154

SOLITARY FIBROUS TUMORS IN THE EXTREMITIES: IMAGING FINDINGS FOR SIX PATIENTS  

PubMed Central

ABSTRACT The purpose of this study was to describe the magnetic resonance imaging (MRI) and computed tomography (CT) findings for solitary fibrous tumors (SFTs) in the extremities in correlation with histopathological findings. Between 2006 and 2013, 6 consecutive patients with SFT in an extremity were studied with MRI (6 patients) and CT (4 patients). Diffusion-weighted images were also performed in 3 patients and dynamic contrast-enhanced CT in 2 patients. All 6 tumors were diagnosed after surgical excision, and the pre-surgical imaging findings were correlated with the histopathological findings. As a result, all 6 patients were female, and each had a clearly palpable, well-circumscribed, round or oval mass adjacent to fascia in an extremity, of less than 10 cm maximum diameter in 5 patients. On MRI, the tumors were iso-intense with muscle on T1-weighted image, and appeared heterogeneous and high-intensity on T2-weighted image. After injection of a contrast agent, the tumors demonstrated strong enhancement. A vascular pedicle was detected in 4 patients with tumors having a maximum diameter more than 5 cm. Diffusion-weighted images demonstrated high signal intensities, and apparent diffusion coefficient values were iso to high compared to muscle (from 1.41–2.10×10–3 mm2/s). All the tumors were benign histopathologically and clinically. In 1 patient, the imaging appearance revealed underlying histopathological components, including fibrous-rich, cellular-rich, and myxoid change areas. In conclusion, a SFT in an extremity comprises a well-circumscribed mass adjacent to fascia having a fibrous-dominant area, strong contrast enhancement, and a vascular pedicle. PMID:25797981

HYODO, RYOTA; KOMADA, TOMOHIRO; TAKADA, AKIRA; KAWAI, HISASHI; ITO, SHINJI; NISHIDA, YOSHIHIRO; NAGANAWA, SHINJI

2015-01-01

155

Solitary fibrous tumors in the extremities: imaging findings for six patients.  

PubMed

The purpose of this study was to describe the magnetic resonance imaging (MRI) and computed tomography (CT) findings for solitary fibrous tumors (SFTs) in the extremities in correlation with histopathological findings. Between 2006 and 2013, 6 consecutive patients with SFT in an extremity were studied with MRI (6 patients) and CT (4 patients). Diffusion-weighted images were also performed in 3 patients and dynamic contrast-enhanced CT in 2 patients. All 6 tumors were diagnosed after surgical excision, and the pre-surgical imaging findings were correlated with the histopathological findings. As a result, all 6 patients were female, and each had a clearly palpable, well-circumscribed, round or oval mass adjacent to fascia in an extremity, of less than 10 cm maximum diameter in 5 patients. On MRI, the tumors were iso-intense with muscle on T1-weighted image, and appeared heterogeneous and high-intensity on T2-weighted image. After injection of a contrast agent, the tumors demonstrated strong enhancement. A vascular pedicle was detected in 4 patients with tumors having a maximum diameter more than 5 cm. Diffusion-weighted images demonstrated high signal intensities, and apparent diffusion coefficient values were iso to high compared to muscle (from 1.41-2.10×10(-3) mm(2)/s). All the tumors were benign histopathologically and clinically. In 1 patient, the imaging appearance revealed underlying histopathological components, including fibrous-rich, cellular-rich, and myxoid change areas. In conclusion, a SFT in an extremity comprises a well-circumscribed mass adjacent to fascia having a fibrous-dominant area, strong contrast enhancement, and a vascular pedicle. PMID:25797981

Hyodo, Ryota; Komada, Tomohiro; Takada, Akira; Kawai, Hisashi; Ito, Shinji; Nishida, Yoshihiro; Naganawa, Shinji

2015-02-01

156

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

157

Development of A Novel Image Guidance Alternative for Patient Localization using Topographic Images for TomoTherapy  

NASA Astrophysics Data System (ADS)

To develop a faster and lower dose topogram based image registration for TomoTherapy as an alternative image guidance tool to volumetric megavoltage computed tomography (MVCT). Topogram procedures were performed for an anthropomorphic thorax phantom on a TomoTherapy HD unit (Accuray Inc., Sunnyvale, CA) using couch speeds from 1-4 cm/s and gantry angles of 0 and 90 degrees, other scanning parameters are: 1 mm imaging jaw, compression factor of 1, 30 seconds scanning duration with all multileaf collimators (MLCs) open. The raw exit detector data was exported after each scan. The topogram was reconstructed from a fan beam source for TomoTherapy beam and detector geometry at a SSD of 85 cm. A reference image, so called Digitally Reconstructed Topogram (DRT) was created by integrating the trajectories through the kVCT simulation with the topogram geometry. Image registration was performed by visually aligning the bony structure in topogram to the DRT. Image resolution was determined by the radius of curvature for the detector array, source to axis distance, source to detector distance, detector spacing, and number of detectors. The localization errors were 1.5, 2.5 mm in medio-lateral and anterior-posterior direction, larger errors in cranial-caudal direction was observed for faster couch speeds (i.e., >=3cm/s). The topographic imaging time was 30 sec (versus 3-5 minutes for MVCT thorax scan) with imaging dose less than 1% of MVCT scan. Topograms with appropriate couch speed provide reliable patient localization images while significantly reducing pre-treatment imaging time. Topogram can be used as an alternative and/or additional patient alignment tool to MVCT on TomoTherapy.

Qi, X. Sharon; White, Benjamin; Low, Daniel A.

2014-03-01

158

Development of patient-specific breast electromagnetic model based on clinical magnetic resonance images  

Microsoft Academic Search

A method for the development of patient-specific electromagnetic breast model based on clinical breast MR images is presented. Numerical example of a breast model demonstrates the feasibility of the method. The developed model is not only limited to the use for modeling clinical studies of microwave imaging for breast cancer detection, but also to cancer treatment using hyperthermia.

Hoi-Shun Lui; Maria Widmark; Göran Starck; Yan Li; Mikael Persson

2010-01-01

159

Evaluation of the effects of patient arm attenuation in SPECT cardiac perfusion imaging  

Microsoft Academic Search

It was hypothesized that the use of attenuation correction could compensate for degradation in the uniformity of apparent localization of imaging agents seen in cardiac walls when patients are imaged with arms at their sides. Noise-free simulations of the digital MCAT phantom were employed to investigate this hypothesis. Four variations in camera size and collimation scheme were investigated. We observed

Dershan Lou; Michael A. King; Tin-Su Pan; Weishi Xia

1996-01-01

160

Intraoperative gamma imaging of axillary sentinel lymph nodes in breast cancer patients  

Microsoft Academic Search

Sentinel lymph node (SLN) biopsy is now standard practice in the management of many breast cancer patients. Localization protocols vary in complexity and rates of success. The least complex involve only intraoperative gamma counting of radiotracer uptake or intraoperative visualization of blue-dye uptake; the most complex involve preoperative gamma imaging, intraoperative counting and intraoperative dye visualization. Intraoperative gamma imaging may

John N. Aarsvod; Carmen M. Greene; Robert A. Mintzer; Sandra F. Grant; Toncred M. Styblo; Naomi P. Alazraki; Bradley E. Patt; Gina M. Caravaglia; Joshua Li; Jan S. Iwanczyk

2006-01-01

161

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

162

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

163

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

164

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

165

Method and system for the diagnosis of disease using retinal image content and an archive of diagnosed human patient data  

DOEpatents

A method for diagnosing diseases having retinal manifestations including retinal pathologies includes the steps of providing a CBIR system including an archive of stored digital retinal photography images and diagnosed patient data corresponding to the retinal photography images, the stored images each indexed in a CBIR database using a plurality of feature vectors, the feature vectors corresponding to distinct descriptive characteristics of the stored images. A query image of the retina of a patient is obtained. Using image processing, regions or structures in the query image are identified. The regions or structures are then described using the plurality of feature vectors. At least one relevant stored image from the archive based on similarity to the regions or structures is retrieved, and an eye disease or a disease having retinal manifestations in the patient is diagnosed based on the diagnosed patient data associated with the relevant stored image(s).

Tobin, Kenneth W; Karnowski, Thomas P; Chaum, Edward

2013-08-06

166

[Epiduroscopy in patients with chronic low back pain without remarkable findings on magnetic resonance imaging].  

PubMed

Two patients with chronic low back pain and sciatica failed to respond to conservative treatments. In these patients, magnetic resonance imaging (MRI) showed no remarkable findings corresponding to their symptoms. We treated these patients using epiduroscopy. Epiduroscopic visualization of the spinal canal permits efficient adhesiolysis and irrigation. One patient got better after two epiduroscopic procedures, and the other did not. Epiduroscopy may be an effective, minimally invasive treatment as well as examination for patients with chronic low back pain without remarkable findings on MRI. PMID:11758339

Saitoh, K; Igarashi, T; Hirabayashi, Y; Horikawa, Y; Seo, N; Motegi, R; Miyashita, K

2001-11-01

167

A CD3 +CD8 + T Cell Population Lacking CD5 Antigen Expression Is Expanded in Peripheral Blood of Human Immunodeficiency Virus-Infected Patients  

Microsoft Academic Search

In this study we analyzed the behavior of a CD3+ T cell subpopulation lacking CD5 antigen expression in PBMC from HIV-1-infected patients. CD3+CD5- lymphocytes were greatly increased in peripheral blood of HIV-1+ patients, accounting for 20.6 ± 9.9% of the total CD3+ cells, compared to seronegative individuals (5.5 ± 3.2%). In both seropositive patients and controls, CD3+CD5- cells belonged to

Stefano Indraccolo; Marta Mion; Rita Zamarchi; Vincenzo Coppola; Francesca Calderazzo; Alberto Amadori; Luigi Chieco-Bianchi

1995-01-01

168

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

169

Patient dose from kilovoltage cone beam computed tomography imaging in radiation therapy  

Microsoft Academic Search

Kilovoltage cone-beam computerized tomography (kV-CBCT) systems integrated into the gantry of linear accelerators can be used to acquire high-resolution volumetric images of the patient in the treatment position. Using on-line software and hardware, patient position can be determined accurately with a high degree of precision and, subsequently, set-up parameters can be adjusted to deliver the intended treatment. While the patient

Mohammad K. Islam; Thomas G. Purdie; Bernhard D. Norrlinger; Hamideh Alasti; Douglas J. Moseley; Michael B. Sharpe; Jeffrey H. Siewerdsen; David A. Jaffray

2006-01-01

170

Nasolacrimal system aeration on computed tomographic imaging: effects of patient positioning and scan orientation  

PubMed Central

Purpose To determine the impact of patient positioning and scan orientation on the appearance of air in the nasolacrimal drainage system on computed tomography (CT) imaging, and the repeatability of the observations. Methods This was a retrospective analysis of CT images for 92 patients. Results Air was found to be present more fully in the upright-position group as compared with the supine-position group. Comparing axial and coronal scan orientation, no difference in aeration was found, except for the nasolacrimal duct in the upright-position group. Conclusion Patient position should be accounted for in diagnostic conclusions and treatment decisions based on CT.

Czyz, Craig N; Bacon, Thomas S; Stacey, Andrew W; Cahill, Eva N; Costin, Bryan R; Karanfilov, Boris I; Cahill, Kenneth V

2015-01-01

171

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

172

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

173

Impacts of MR spectroscopic imaging on glioma patient management.  

PubMed

Magnetic resonance (MR) modalities are routine imaging tools in the diagnosis and management of gliomas. MR spectroscopic imaging (MRSI), which relies on the metabolic characteristics of tissues, has been developed to accelerate the understanding of gliomas and to aid in effective clinical decision making and development of targeted therapies. In this review, the potentials and practical challenges to frequently use this technique in clinical management of gliomas are discussed. The applications of new biomarkers detectable by MRSI in differential glioma diagnosis, pre- and post-treatment evaluations, and neurosurgery are also addressed. PMID:24628262

Chronaiou, Ioanna; Stensjøen, Anne Line; Sjøbakk, Torill Eidhammer; Esmaeili, Morteza; Bathen, Tone Frost

2014-05-01

174

Modeling Cardiovascular Anatomy from Patient-Specific Imaging  

NASA Astrophysics Data System (ADS)

The importance of modern imaging techniques for capturing detailed structural information of a biological system cannot be understated. Unfortunately images do not reveal the "full functional story" and a spatially realistic computer model is often necessary for a comprehensive understanding of the complicated structural and physiological properties of the biological system's entities under investigation [1]. Deeper insights into structure-to-function relationships of different entities is achieved via finite element simulations of the modeled biomedical process. A 3D (three dimensional) finite element meshed computer model of the biological system is therefore a first step to perform such simulations.

Bajaj, Chandrajit; Goswami, Samrat

175

Magnetic resonance imaging of the chest in the evaluation of cancer patients: state of the art  

PubMed Central

Magnetic resonance imaging (MRI) has several advantages in the evaluation of cancer patients with thoracic lesions, including involvement of the chest wall, pleura, lungs, mediastinum, esophagus and heart. It is a quite useful tool in the diagnosis, staging, surgical planning, treatment response evaluation and follow-up of these patients. In the present review, the authors contextualize the relevance of MRI in the evaluation of thoracic lesions in cancer patients. Considering that MRI is a widely available method with high contrast and spatial resolution and without the risks associated with the use of ionizing radiation, its use combined with new techniques such as cine-MRI and functional methods such as perfusion- and diffusion-weighted imaging may be useful as an alternative tool with performance comparable or complementary to conventional radiological methods such as radiography, computed tomography and PET/CT imaging in the evaluation of patients with thoracic neoplasias. PMID:25798006

Guimaraes, Marcos Duarte; Hochhegger, Bruno; Santos, Marcel Koenigkam; Santana, Pablo Rydz Pinheiro; Sousa, Arthur Soares; Souza, Luciana Soares; Marchiori, Edson

2015-01-01

176

Prognostic PET 18F-FDG uptake imaging features are associated with major oncogenomic alterations in patients with resected non-small cell lung cancer  

PubMed Central

Although 18F-2-fluoro-2-deoxyglucose (FDG) uptake during positron emission tomography (PET) predicts post-surgical outcome in patients with non-small-cell lung cancer (NSCLC), the biologic basis for this observation is not fully understood. Here we analyzed 25 tumors from NSCLC patients to identify tumor 18F-FDG PET uptake features associated with gene expression signatures and survival. Fourteen quantitative PET imaging features describing FDG uptake were correlated with gene expression for single genes and co-expressed gene clusters (metagenes). For each FDG uptake feature, an associated metagene signature was derived and a prognostic model was identified in an external and tested in a validation cohort of NSCLC patients. Four of 8 single genes associated with FDG uptake (LY6E, RNF149, MCM6, FAP) were also associated with survival. The most prognostic metagene signature was associated with a multivariate FDG uptake feature (SUVmax, SUVvariance and SUVPCA2), each highly associated with survival in the external (HR 5.87, confidence interval [CI] 2.49-13.8) and validation (HR 6.12, CI 1.08-34.8) cohorts, respectively. Cell cycle, proliferation, death, and self-recognition pathways were altered in this radiogenomic profile. Together, our findings suggest that leveraging tumor genomics with an expanded collection of PET-FDG imaging features may enhance our understanding of FDG uptake as an imaging biomarker beyond its association with glycolysis. PMID:22710433

Nair, Viswam S.; Gevaert, Olivier; Davidzon, Guido; Napel, Sandy; Graves, Edward E.; Hoang, Chuong D.; Shrager, Joseph B.; Quon, Andrew; Rubin, Daniel L.; Plevritis, Sylvia K.

2012-01-01

177

Evidence for the Expanding Universe  

NSDL National Science Digital Library

In this activity, students examine the first line of evidence, galactic motion, for the notion of an expanding universe. By examining the spectrum of light from a galaxy, students can determine whether a galaxy is moving toward or away from us, and how fast. Students will look at optical images of four galaxies, compare the emission spectra from these same four galaxies, and measure the wavelength of the red hydrogen line for each galaxy. This activity is part of the "Cosmic Questions" educator's guide developed to support the Cosmic Questions exhibit. This activity can be used in conjunction with, or independently of, the exhibit.

178

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

179

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

180

Wide-field imaging and OCT vs clinical evaluation of patients referred from diabetic retinopathy screening  

PubMed Central

Purpose Compare wide-field Optomap imaging and optical coherence tomography (OCT) with clinical examination in diabetic retinopathy (DR). Methods Patients referred from Diabetic Eye Screening Programmes to three centres underwent dilated ophthalmoscopy and were assigned a DR grade. Wide-field colour imaging and OCT were then examined by the same clinician at that visit and a combined grade was assigned. Independent graders later reviewed the images and assigned an imaging-only grade. These three grades (clinical, combined, and imaging) were compared. The method that detected the highest grade of retinopathy, including neovascularisation, was determined. Results Two thousand and forty eyes of 1023 patients were assessed. Wide-field imaging compared with clinical examination had a sensitivity and specificity of 73% and 96%, respectively, for detecting proliferative DR, 84% and 69% for sight-threatening DR, and 64% and 90% for diabetic macular oedema. Imaging alone found 35 more eyes with new vessels (19% of eyes with new vessels) and the combined grade found 14 more eyes than clinical examination alone. Conclusions Assessment of wide-field images and OCT alone detected more eyes with higher grades of DR compared with clinical examination alone or when combined with imaging in a clinical setting. The sensitivity was not higher as the techniques were not the same, with imaging alone being more sensitive. Wide-field imaging with OCT could be used to assess referrals from DR screening to determine management, to enhance the quality of assessment in clinics, and to follow-up patients whose DR is above the screening referral threshold but does not actually require treatment. PMID:25592127

Manjunath, V; Papastavrou, V; Steel, D H W; Menon, G; Taylor, R; Peto, T; Talks, J

2015-01-01

181

Wide-field imaging and OCT vs clinical evaluation of patients referred from diabetic retinopathy screening.  

PubMed

PurposeCompare wide-field Optomap imaging and optical coherence tomography (OCT) with clinical examination in diabetic retinopathy (DR).MethodsPatients referred from Diabetic Eye Screening Programmes to three centres underwent dilated ophthalmoscopy and were assigned a DR grade. Wide-field colour imaging and OCT were then examined by the same clinician at that visit and a combined grade was assigned. Independent graders later reviewed the images and assigned an imaging-only grade. These three grades (clinical, combined, and imaging) were compared. The method that detected the highest grade of retinopathy, including neovascularisation, was determined.ResultsTwo thousand and forty eyes of 1023 patients were assessed. Wide-field imaging compared with clinical examination had a sensitivity and specificity of 73% and 96%, respectively, for detecting proliferative DR, 84% and 69% for sight-threatening DR, and 64% and 90% for diabetic macular oedema. Imaging alone found 35 more eyes with new vessels (19% of eyes with new vessels) and the combined grade found 14 more eyes than clinical examination alone.ConclusionsAssessment of wide-field images and OCT alone detected more eyes with higher grades of DR compared with clinical examination alone or when combined with imaging in a clinical setting. The sensitivity was not higher as the techniques were not the same, with imaging alone being more sensitive. Wide-field imaging with OCT could be used to assess referrals from DR screening to determine management, to enhance the quality of assessment in clinics, and to follow-up patients whose DR is above the screening referral threshold but does not actually require treatment. PMID:25592127

Manjunath, V; Papastavrou, V; Steel, D H W; Menon, G; Taylor, R; Peto, T; Talks, J

2015-03-01

182

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

183

Different imaging characteristics of concurrent pituitary adenomas in a patient with Cushing's disease.  

PubMed

We report a patient with Cushing's disease (CD) and two pituitary adenomas that demonstrated different imaging characteristics and therefore suggest an alternative imaging strategy for these patients. A 42-year-old woman presented with signs and symptoms of CD. Biochemical evaluation confirmed hypercortisolemia and suggested CD. On pituitary MRI with spoiled gradient recalled acquisition in the steady-state and T1-weighted spin echo protocols, a 5mm hypoenhancing region typical for a pituitary adenoma was identified on the left. However, after surgical resection the patient remained hypercortisolemic and pathology revealed a non-functional adenoma. At early repeat surgical exploration a 10mm adenoma was found in the right side of the gland. Postoperatively the patient became hypocortisolemic and pathology demonstrated an adrenocorticotropic hormone (ACTH)-staining adenoma. On review of the initial MRI this tumor corresponded to a region of contrast retention best visualized on delayed fluid attenuated inversion recovery (FLAIR) imaging. While the incidentaloma in this case demonstrated classical imaging characteristics of a pituitary adenoma the larger ACTH-secreting tumor was best appreciated by contrast retention. This suggests a role for delayed postcontrast FLAIR imaging in the preoperative evaluation of CD. ACTH-secreting tumors causing CD cause significant morbidity. Due to their small size, a pituitary adenoma is frequently not identified on imaging despite endocrinologic testing suggesting CD. Regardless of improvements in MRI, many tumors are only identified at surgical exploration. PMID:25827866

Mehta, Gautam U; Montgomery, Blake K; Raghavan, Pooja; Sharma, Susmeeta; Nieman, Lynnette K; Patronas, Nicholas; Oldfield, Edward H; Chittiboina, Prashant

2015-05-01

184

Advanced diffusion imaging sequences could aid assessing patients with focal cortical dysplasia and epilepsy?  

PubMed Central

Summary Malformations of cortical development (MCD), particularly focal cortical dysplasia (FCD), are a common cause of refractory epilepsy but are often invisible on structural imaging. NODDI (neurite orientation dispersion and density imaging) is an advanced diffusion imaging technique that provides additional information on tissue microstructure, including intracellular volume fraction (ICVF), a marker of neurite density. We applied this technique in 5 patients with suspected dysplasia to show that the additional parameters are compatible with the underlying disrupted tissue microstructure and could assist in the identification of the affected area. The consistent finding was reduced ICVF in the area of dysplasia. In one patient, an area of reduced ICVF and increased fibre dispersion was identified that was not originally seen on the structural imaging. The focal reduction in ICVF on imaging is compatible with previous iontophoretic data in surgical specimens, was more conspicuous than on other clinical or diffusion images (supported by an increased contrast-to-noise ratio) and more localised than on previous DTI studies. NODDI may therefore assist the clinical identification and localisation of FCD in patients with epilepsy. Future studies will assess this technique in a larger cohort including MRI negative patients. PMID:24315018

Winston, Gavin P.; Micallef, Caroline; Symms, Mark R.; Alexander, Daniel C.; Duncan, John S.; Zhang, Hui

2014-01-01

185

Imaging of Cerebral Blood Flow in Patients with Severe Traumatic Brain Injury in the Neurointensive Care  

PubMed Central

Ischemia is a common and deleterious secondary injury following traumatic brain injury (TBI). A great challenge for the treatment of TBI patients in the neurointensive care unit (NICU) is to detect early signs of ischemia in order to prevent further advancement and deterioration of the brain tissue. Today, several imaging techniques are available to monitor cerebral blood flow (CBF) in the injured brain such as positron emission tomography (PET), single-photon emission computed tomography, xenon computed tomography (Xenon-CT), perfusion-weighted magnetic resonance imaging (MRI), and CT perfusion scan. An ideal imaging technique would enable continuous non-invasive measurement of blood flow and metabolism across the whole brain. Unfortunately, no current imaging method meets all these criteria. These techniques offer snapshots of the CBF. MRI may also provide some information about the metabolic state of the brain. PET provides images with high resolution and quantitative measurements of CBF and metabolism; however, it is a complex and costly method limited to few TBI centers. All of these methods except mobile Xenon-CT require transfer of TBI patients to the radiological department. Mobile Xenon-CT emerges as a feasible technique to monitor CBF in the NICU, with lower risk of adverse effects. Promising results have been demonstrated with Xenon-CT in predicting outcome in TBI patients. This review covers available imaging methods used to monitor CBF in patients with severe TBI. PMID:25071702

Rostami, Elham; Engquist, Henrik; Enblad, Per

2014-01-01

186

Initial Clinical Experience Performing Patient Treatment Verification With an Electronic Portal Imaging Device Transit Dosimeter  

SciTech Connect

Purpose: To prospectively evaluate a 2-dimensional transit dosimetry algorithm's performance on a patient population and to analyze the issues that would arise in a widespread clinical adoption of transit electronic portal imaging device (EPID) dosimetry. Methods and Materials: Eleven patients were enrolled on the protocol; 9 completed and were analyzed. Pretreatment intensity modulated radiation therapy (IMRT) patient-specific quality assurance was performed using a stringent local 3%, 3-mm ? criterion to verify that the planned fluence had been appropriately transferred to and delivered by the linear accelerator. Transit dosimetric EPID images were then acquired during treatment and compared offline with predicted transit images using a global 5%, 3-mm ? criterion. Results: There were 288 transit images analyzed. The overall ? pass rate was 89.1% ± 9.8% (average ± 1 SD). For the subset of images for which the linear accelerator couch did not interfere with the measurement, the ? pass rate was 95.7% ± 2.4%. A case study is presented in which the transit dosimetry algorithm was able to identify that a lung patient's bilateral pleural effusion had resolved in the time between the planning CT scan and the treatment. Conclusions: The EPID transit dosimetry algorithm under consideration, previously described and verified in a phantom study, is feasible for use in treatment delivery verification for real patients. Two-dimensional EPID transit dosimetry can play an important role in indicating when a treatment delivery is inconsistent with the original plan.

Berry, Sean L., E-mail: BerryS@MSKCC.org [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York (United States); Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Polvorosa, Cynthia; Cheng, Simon; Deutsch, Israel; Chao, K. S. Clifford; Wuu, Cheng-Shie [Department of Radiation Oncology, Columbia University, New York, New York (United States)

2014-01-01

187

Image quality in obese patients undergoing 256-row computed tomography coronary angiography.  

PubMed

To evaluate, objectively and subjectively, the feasibility of 256-row computed tomography coronary angiography (CTCA) in obese patients. 256-row CTCA was performed in 68 symptomatic patients (age 61 ± 10 years, 37 females), 39 obese (body mass index-BMI > 30 kg/m(2)) and 29 non-obese. Retrospective analysis was performed by two observers who assessed the image quality of each coronary segment using a 4-point subjective scale (1 excellent to 4 non-diagnostic), and another blinded observer measured objective image parameters. BMI in the obese group was 35 ± 5 (32-65) Kg/m(2), and 24 ± 3 (16-29) Kg/m(2) in the non-obese (P = 0.004). Average subjective image quality was similar in obese (1.41 ± 0.40) and non-obese (1.34 ± 0.40) patients, P = 0.17. Proportion of coronary artery segments with non-diagnostic image quality was low in both groups (0.7% in obese and 0.2% in non-obese, P = 0.31). Signal to noise and contrast to noise ratios were not significantly lower in obese than in non-obese patients (9.4 ± 3 vs. 12 ± 2.5, P = 0.16 and 11.1 ± 3.8 vs. 13.7 ± 2.9, P = 0.07 respectively). However, dose length product (1167 ± 567 vs. 827 ± 375 mGy × cm, P = 0.014) and image noise (44 ± 13 vs. 35 ± 5 HU, P < 0.001) were higher in the obese patient group. Image quality was preserved in obese patients undergoing 256-row CTCA at the cost of increased radiation exposure and image noise. PMID:21424151

Segev, Orit Lesman; Gaspar, Tamar; Halon, David A; Peled, Nathan; Domachevsky, Liran; Lewis, Basil S; Rubinshtein, Ronen

2012-03-01

188

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

189

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

PubMed

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. PMID:23920245

Ding, George X; Malcolm, Arnold W

2013-09-01

190

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

191

Imaging of Microglia in Patients with Neurodegenerative Disorders  

PubMed Central

Microglia constitute the main immune defense in the central nervous system. In response to neuronal injury, microglia become activated, acquire phagocytic properties, and release a wide range of pro-inflammatory mediators that are essential for the annihilation of the neuronal insult. Although the role of microglial activation in acute neuronal damage is well defined, the pathophysiological processes underlying destructive or protective role to neurons following chronic exposure to microglial activation is still a subject of debate. It is likely that chronic exposure induces detrimental effects by promoting neuronal death through the release of neurotoxic factors. Positron emission tomography (PET) imaging with the use of translocator protein (TSPO) radioligands provides an in vivo tool for tracking the progression and severity of neuroinflammation in neurodegenerative disease. TSPO expression is correlated to the extent of microglial activation and the measurement of TSPO uptake in vivo with PET is a useful indicator of active disease. Although understanding of the interaction between radioligands and TSPO is not completely clear, there is a wide interest in application of TSPO imaging in neurodegenerative disease. In this article, we aim to review the applications of in vivo microglia imaging in neurodegenerative disorders such as Parkinson’s disease, Huntington’s disease, Dementias, and Multiple Sclerosis. PMID:22661951

Politis, Marios; Su, Paul; Piccini, Paola

2012-01-01

192

Expanded spectrum of exon 33 and 34 mutations in SRCAP and follow-up in patients with Floating-Harbor syndrome.  

PubMed

BackgroundFloating-Harbor syndrome is a rare autosomal dominant short stature syndrome with retarded speech development, intellectual disability and dysmorphic facial features. Recently dominant mutations almost exclusively located in exon 34 of the Snf2-related CREBBP activator protein gene were identified to cause FHS.MethodsHere we report the genetic analysis of 5 patients fulfilling the diagnostic criteria of FHS obtained by Sanger sequencing. All of them presented with short stature, speech delay as well as psychomotor delay and typical facial dysmorphism. Three patients showed a good response to growth hormone treatment.ResultsTwo patients demonstrate novel, heterozygous de novo frameshift mutations in exon 34 (c.7396delA and c.7218dupT) leading to premature stop mutations in SRCAP (p.Val2466Tyrfs*9 and p.Gln2407Serfs*36, respectively). In two further patients we found already known SRCAP mutations in exon 34, c.7330C¿>¿T and c.7303C¿>¿T, respectively, which also lead to premature stop codons: p.Arg2444* and p.Arg2435*. In one patient, we identified a novel de novo stop mutation in exon 33 (c.6985C¿>¿T, p.Arg2329*) demonstrating that not all FHS cases are caused by mutations in exon 34 of SRCAP.ConclusionsOur data confirm a mutational hot spot in the final exon of SRCAP in the majority of FHS patients but also show that exon 33 of this gene can be affected. PMID:25433523

Seifert, Wenke; Meinecke, Peter; Krüger, Gabriele; Rossier, Eva; Heinritz, Wolfram; Wüsthof, Achim; Horn, Denise

2014-11-30

193

Optimization of expander plants  

SciTech Connect

A computer program that uses the Tomich technique to solve multistage, multi-feed distillation problems was modified. The MSEQ method was utilized to generate initial temperature and vapor rate profiles. The modified fractionator program coupled with the MSEQ method was used to generate required rigorous data for expander-plant demethanizer splits. Furthermore, a shortcut method was developed to facilitate expander process simulation. Calculated demethanizer results from a simulation were compared with a commercial program with good agreement. The results from the shortcut method were in good agreement with rigorous calculations. Computer simulations were made for four different natural gases ranging from lean to rich in liquefiable hydrocarbons for various turboexpander plant processes. These processes included self-refrigerated expander process with/without external refrigeration, and with/without demethanizer heat recovery. Only lean gases can be utilized in the self-refrigerated expander process with high ethane recovery. While the use of external refrigeration in conjunction with the expander process can reduce overall horsepower requirements, it may not be economical to do so. In general, the processing should be carried out at the highest practical processing pressure. The use of demethanizer heat recovery is an efficient method to reduce both refrigeration horsepower and recompression energy requirements. This work emphasizes high ethane recovery. Further study of expander processes emphasizing ethane rejection is advisable.

Wang, W.B.

1985-01-01

194

Longitudinal evaluation of patients with oral potentially malignant disorders using optical imaging and spectroscopy  

NASA Astrophysics Data System (ADS)

Dysplastic and cancerous alterations in oral tissue can be detected noninvasively in vivo using optical techniques including autofluorescence imaging, high-resolution imaging, and spectroscopy. Interim results are presented from a longitudinal study in which optical imaging and spectroscopy were used to evaluate the progression of lesions over time in patients at high risk for development of oral cancer. Over 100 patients with oral potentially malignant disorders have been enrolled in the study to date. Areas of concern in the oral cavity are measured using widefield autofluorescence imaging and depth-sensitive optical spectroscopy during successive clinical visits. Autofluorescence intensity patterns and autofluorescence spectra are tracked over time and correlated with clinical observations. Patients whose lesions progress and who undergo surgery are also measured in the operating room immediately prior to surgery using autofluorescence imaging and spectroscopy, with the addition of intraoperative high-resolution imaging to characterize nuclear size, nuclear crowding, and tissue architecture at selected sites. Optical measurements are compared to histopathology results from biopsies and surgical specimens collected from the measured sites. Autofluorescence imaging and spectroscopy measurements are continued during post-surgery followup visits. We examined correlations between clinical impression and optical classification over time with an average followup period of 4 months. The data collected to date suggest that multimodal optical techniques may aid in noninvasive monitoring of the progression of oral premalignant lesions, biopsy site selection, and accurate delineation of lesion extent during surgery.

Schwarz, Richard A.; Pierce, Mark C.; Mondrik, Sharon; Gao, Wen; Quinn, Mary K.; Bhattar, Vijayashree; Williams, Michelle D.; Vigneswaran, Nadarajah; Gillenwater, Ann M.; Richards-Kortum, Rebecca

2012-02-01

195

Patient-specific biomechanical model as whole-body CT image registration tool.  

PubMed

Whole-body computed tomography (CT) image registration is important for cancer diagnosis, therapy planning and treatment. Such registration requires accounting for large differences between source and target images caused by deformations of soft organs/tissues and articulated motion of skeletal structures. The registration algorithms relying solely on image processing methods exhibit deficiencies in accounting for such deformations and motion. We propose to predict the deformations and movements of body organs/tissues and skeletal structures for whole-body CT image registration using patient-specific non-linear biomechanical modelling. Unlike the conventional biomechanical modelling, our approach for building the biomechanical models does not require time-consuming segmentation of CT scans to divide the whole body into non-overlapping constituents with different material properties. Instead, a Fuzzy C-Means (FCM) algorithm is used for tissue classification to assign the constitutive properties automatically at integration points of the computation grid. We use only very simple segmentation of the spine when determining vertebrae displacements to define loading for biomechanical models. We demonstrate the feasibility and accuracy of our approach on CT images of seven patients suffering from cancer and aortic disease. The results confirm that accurate whole-body CT image registration can be achieved using a patient-specific non-linear biomechanical model constructed without time-consuming segmentation of the whole-body images. PMID:25721296

Li, Mao; Miller, Karol; Joldes, Grand Roman; Doyle, Barry; Garlapati, Revanth Reddy; Kikinis, Ron; Wittek, Adam

2015-05-01

196

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

PubMed Central

Purpose To measure natural image search performance in patients with central vision impairment. To evaluate the performance effect for a JPEG based image enhancement technique using the visual search task. Method 150 JPEG images were presented on a touch screen monitor in either an enhanced or original version to 19 patients (visual acuity 0.4 to 1.2 logMAR, 6/15 to 6/90, 20/50 to 20/300) and 7 normally sighted controls (visual acuity ?0.12 to 0.1 logMAR, 6/4.5 to 6/7.5, 20/15 to 20/25). Each image fell into one of three categories: faces, indoors, and collections. The enhancement was realized by moderately boosting a mid-range spatial frequency band in the discrete cosine transform (DCT) coefficients of the image luminance component. Participants pointed to an object in a picture that matched a given target displayed at the upper-left corner of the monitor. Search performance was quantified by the percentage of correct responses, the median search time of correct responses, and an “integrated performance” measure – the area under the curve of cumulative correct response rate over search time. Results Patients were able to perform the search tasks but their performance was substantially worse than the controls. Search performances for the 3 image categories were significantly different (p?0.001) for all the participants, with searching for faces being the most difficult. When search time and correct response were analyzed separately, the effect of enhancement led to increase in one measure but decrease in another for many patients. Using the integrated performance, it was found that search performance declined with decrease in acuity (p=0.005). An improvement with enhancement was found mainly for the patients whose acuity ranged from 0.4 to 0.8 logMAR (6/15 to 6/38, 20/50 to 20/125). Enhancement conferred a small but significant improvement in integrated performance for indoor and collection images (p=0.025) in the patients. Conclusion Search performance for natural images can be measured in patients with impaired vision to evaluate the effect of image enhancement. Patients with moderate vision loss might benefit from the moderate level of enhancement used here. PMID:22540926

Luo, Gang; Satgunam, PremNandhini; Peli, Eli

2012-01-01

197

Neural processing of negative word stimuli concerning body image in patients with eating disorders: An fMRI study  

Microsoft Academic Search

Eating disorders (EDs) are associated with abnormalities of body image perception. The aim of the present study was to investigate the functional abnormalities in brain systems during processing of negative words concerning body images in patients with EDs. Brain responses to negative words concerning body images (task condition) and neutral words (control condition) were measured using functional magnetic resonance imaging

Yoshie Miyake; Yasumasa Okamoto; Keiichi Onoda; Naoko Shirao; Yuri Okamoto; Yoko Otagaki; Shigeto Yamawaki

2010-01-01

198

Correction for patient and organ movement in SPECT: application to exercise thallium-201 cardiac imaging  

SciTech Connect

We describe a technique for correction of artifacts in exercise /sup 201/Tl single photon emission computed tomography (SPECT) images arising from abrupt or gradual translational movement of the heart during acquisition. The procedure involves the tracking of the center of the heart in serial projection images using an algorithm which we call diverging squares. Each projection image is then realigned in the x-y plane so that the heart center conforms to the projected position of a fixed point in space. The shifted projections are reconstructed using the normal filtered backprojection algorithm. In validation studies, the motion correction procedure successfully eliminated movement artifacts in a heart phantom. Image quality was also improved in over one-half of 36 exercise thallium patient studies. The corrected images had smoother and more continuous left ventricular walls, greater clarity of the left ventricular cavity, and reduced streak artifacts. Rest injected or redistribution images, however, were often made worse, due to reduced heart to liver activity ratios and poor tracking of the heart center. Analysis of curves of heart position versus projection angle suggests that translation of the heart is common during imaging after exercise, and results from both abrupt patient movements, and a gradual upward shift of the heart. Our motion correction technique appears to represent a promising new approach for elimination of movement artifacts and enhancement of resolution in exercise /sup 201/Tl cardiac SPECT images.

Geckle, W.J.; Frank, T.L.; Links, J.M.; Becker, L.C.

1988-04-01

199

Development of Fast and Highly Efficient Gas Ionization Chamber For Patient Imaging and Dosimetry in Radiation Therapy  

SciTech Connect

In radiation therapy of cancer, more accurate delivery techniques spur the need for improved patient imaging during treatment. To this purpose, the megavoltage radiation protocol that is used for treatment is also used for imaging.

R. Hinderler; H. Keller; T.R. Mackie; M.L. Corradini

2003-09-08

200

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

201

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

PubMed

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

Guimaraes, Marcos D; Bitencourt, Almir G V; Marchiori, Edson; Chojniak, Rubens; Gross, Jefferson L; Kundra, Vikas

2014-01-01

202

Prevalence of microdeletion 22q11 in patients with hypernasal speech due to velopharyngeal insufficiency: Expanded phenotype and clinical comparison to nondeletion  

SciTech Connect

Microdeletion 22q11.2 has been reported as a frequent ethiology of both velocardiofacial (VCF) and DiGeorge syndromes. We have studied the prevalence of microdeletion 22q11 in a group of patients ascertained through a Speech and Language clinic presenting with (1) velopharyngeal insufficiency (VPI) and (2) difficultly in school. Growth parameters were measured, and facies were scored for features of VCF. Microdeletions were detected at locus D22S75 by FISH with probe N25 (Oncor), and at 22q11.2 with high resolution banding analysis (HRB). One child with typical VCF facies was considered to have a deletion at 22q11 with HRB, but is not deleted with N25, indicating that N25 may not detect all deletion patients. An additional 8/30 children tested to date were deleted with the N25 probe. Heart defects were present in only 2/8 deletion patients: VSD/ASD and PS/AS. One N25 deletion patient was atypica; he has a tall, lanky habitus (height = 90%), and facies not characteristic of CVF. As expected, there is a trend to lower head size, smaller ear size, and more typical facies in deletion patients; however, four of the nondeletion patients also had a clinical diagnosis of VCF. Medially displaced carotid arteries were present in both groups, which is therefore not a diagnostic feature of microdeletion 22q11. Our findings indicate that the microdeletion 22q11 is frequent (26% in this series) in a population with VPI, even when not selected for typical facies. We believe this series supports the view that microdeletion 22q11 has a broader clinical phenotype than previously recognized.

Siegel-Bartelt, J.; Cytrynbaum, C.; Witzel, M.A.; Teshima, I.E. [Univ. of Toronto, Ontario (Canada)

1994-09-01

203

Effect of imaging and catheter characteristics on clinical outcome for patients in the PRECISE study  

PubMed Central

The PRECISE study used convection enhanced delivery (CED) to infuse IL13-PE38QQR in patients with recurrent glioblastoma multiforme (GBM) and compared survival to Gliadel Wafers (GW). The objectives of this retrospective evaluation were to assess: (1) catheter positioning in relation to imaging features and (2) to examine the potential impact of catheter positioning, overall catheter placement and imaging features on long term clinical outcome in the PRECISE study. Catheter positioning and overall catheter placement were scored and used as a surrogate of adequate placement. Imaging studies obtained on day 43 and day 71 after resection were each retrospectively reviewed. Catheter positioning scores, catheter overall placement scores, local tumor control and imaging change scores were reviewed and correlated using Generalized Linear Mixed Models. Cox PH regression analysis was used to examine whether these imaging based variables predicted overall survival (OS) and progression free survival (PFS) after adjusting for age and KPS. Of 180 patients in the CED group, 20 patients did not undergo gross total resection. Of the remaining 160 patients only 53% of patients had fully conforming catheters in respect to overall placement and 51% had adequate catheter positioning scores. Better catheter positioning scores were not correlated with local tumor control (P = 0.61) or imaging change score (P = 0.86). OS and PFS were not correlated with catheter positioning score (OS: P = 0.53; PFS: P = 0.72 respectively), overall placement score (OS: P = 0.55; PFS: P = 0.35) or imaging changes on day 43 MRI (P = 0.88). Catheter positioning scores and overall catheter placement scores were not associated with clinical outcome in this large prospective trial. PMID:20563833

Polley, Mei-Yin; Lee, Benjamin; Kunwar, Sandeep; Pedain, Christoph; Wembacher-Schröder, Eva; Mittermeyer, Stephan; Westphal, Manfred; Sampson, John H.; Vogelbaum, Michael A.; Croteau, David; Chang, Susan M.

2010-01-01

204

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

205

Ultrasound, computed tomography, and magnetic resonance imaging of ovarian vein thrombosis in obstetrical and nonobstetrical patients.  

PubMed

Ovarian vein thrombosis is an uncommon clinical entity, most familiar to radiologists as a source of postpartum sepsis, which, if unrecognized and left untreated, has the potential for septic shock, pulmonary thromboembolism, and death. Ovarian vein thrombosis also occurs with other common inflammatory and malignant conditions in the nonobstetrical patient. This article reviews the pathophysiology, predisposing conditions, clinical findings, imaging features on ultrasonography, computed tomography, and magnetic resonance imaging of acute and chronic ovarian vein thrombosis and its appropriate clinical management. PMID:20870377

Virmani, Vivek; Kaza, Ravi; Sadaf, Arifa; Fasih, Najla; Fraser-Hill, Margaret

2012-05-01

206

The influence of patient centering on CT dose and image noise  

SciTech Connect

Although x-ray intensity shaping filters (bowtie filters) have been used since the introduction of some of the earliest CT scanner models, the clinical implications on dose and noise are not well understood. To achieve the intended dose and noise advantage requires the patient to be centered in the scan field of view. In this study we explore the implications of patient centering in clinical practice. We scanned various size and shape phantoms on a GE LightSpeed VCT scanner using each available source filter with the phantom centers positioned at 0, 3, and 6 cm below the center of rotation (isocenter). Surface doses were measured along with image noise over a large image region. Regression models of surface dose and noise were generated as a function of phantom size and centering error. Methods were also developed to determine the amount of miscentering using a scout scan projection radiograph (SPR). These models were then used to retrospectively evaluate 273 adult body patients for clinical implications. When miscentered by 3 and 6 cm, the surface dose on a 32 cm CTDI phantom increased by 18% and 41% while image noise also increased by 6% and 22%. The retrospective analysis of adult body scout SPR scans shows that 46% of patients were miscentered in elevation by 20-60 mm with a mean position 23 mm below the center of rotation (isocenter). The analysis indicated a surface dose penalty of up to 140% with a mean dose penalty of 33% assuming that tube current is increased to compensate for the increased noise due to miscentering. Clinical image quality and dose efficiency can be improved on scanners with bowtie filters if care is exercised when positioning patients. Automatically providing patient specific centering and scan parameter selection information can help the technologist improve workflow, achieve more consistent image quality and reduce patient dose.

Toth, Thomas; Ge Zhanyu; Daly, Michael P. [CT Systems Engineering W-1140, G.E. Healthcare, General Electric Company, 3000 N. Grandview Boulevard, Waukesha, Wisconsin 53201-0414 (United States); Electromagnetics Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

2007-07-15

207

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

208

[Clinical care of lung cancer patients with body image changes after targeted therapy].  

PubMed

Lung cancer has a relatively short survival prognosis and advanced disease progression. Therefore, targeted therapy has become one of the most frequent treatments of this disease. Targeted therapy has several features that effectively extend the survival period; is easy to apply and use; and has fewer side effects than chemotherapy. Therefore, this therapy approach has become the preferred choice of patients with advanced lung cancer. However, current targeted therapies like Iressa and Tarceva produce side effects such as skin dryness and acneiform eruption that may bother patients. These side effects may further cause patient concern over negative changes in their body image, and these concerns may influence their work and social lives. Additionally, some patients treated with targeted therapy worry about their chances of survival if they reduce or stop the medication to avoid the side effects. Consequently, patients may struggle with both physical and psychological impacts, and may have problems sustaining a good quality of life. This article focuses on delivering relevant information to patients receiving targeted therapy who suffer from dermatological toxicity and damage to their body image. We demonstrate an assessment tool and information to help patients cope with physical and psychosocial issues through daily skin care routines, mental / psychological supports, and cognitive behavior therapy. These measures may help patients rebuild a positive self-concept. We plan to develop further associated training to provide professionals / care providers with the appropriate knowledge and skills to care for cancer patients in a resource-limited environment so that they may improve the quality of nursing care for patients with body image changes. PMID:25116319

Chan, Jui-Chun; Liao, Yu-Chien; Lee, Yun-Hsiang; Lai, Yeur-Hur

2014-08-01

209

Multimodality Imaging in an Adult Patient with Scimitar Syndrome  

PubMed Central

The “Scimitar syndrome” is a rare congenital anomaly characterized by combination of partial or complete pulmonary venous return from the right lung to the inferior vena cava either above or below the diaphragm together with hypoplasia of the right lung and sometimes systemic arterial supply to the right lung. In this case, multimodality imaging findings such as the vein draining into the inferior vena cava, the presence of hypertrophied and dilated right ventricle, the absence of other cardiac abnormalities, displacement of the heart without malrotation and the mediastinum to the right, normal bronchial and vascular continuity in the whole lung, absence of pulmonary sequestration and systemic collaterals, normal perfusion and systolic functions of the left ventricle were reported. PMID:24963450

Karaçal?o?lu, Alper Özgür; Gümü?, Seyfettin; ?nce, Semra; Demirkol, Sait

2014-01-01

210

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

211

Clinical and imaging characterization of a patient with idiopathic progressive ataxia and palatal tremor.  

PubMed

We describe clinical and imaging features of a patient with sporadic progressive ataxia and palatal tremor (PAPT) of unknown etiology. There was hypertrophy of bilateral inferior olivary nuclei with hyperintense T2-weighted signal and mild cerebellar atrophy at brain magnetic resonance imaging. 18F-fluoro-2-desoxy-d-glucose positron emission tomography scanning (FDG-PET) showed hypometabolism in the red nucleus, external globus pallidus and precuneus while FP-CIT-SPECT imaging revealed mild and progressive loss of striatal dopaminergic terminals. Our findings suggest that in idiopathic PAPT involvement of the dentato-rubro-olivary pathway occurs along with some dopaminergic dysfunction. PMID:17662021

Cilia, R; Righini, A; Marotta, G; Benti, R; Marconi, R; Isaias, I U; Pezzoli, G; Antonini, A

2007-08-01

212

Follow-up study using iodine-131 metaiodobenzylguanidine imaging in a patient with neuroblastoma  

SciTech Connect

A new radiopharmaceutical, I-131 metaiodobenzylguanidine (I-131 MIBG) was used to determine the location and to follow-up tumors in a 13-month-old girl with neuroblastoma. I-131 MIBG imaging revealed both a primary abdominal tumor and a distant metastatic orbital tumor. Follow-up study with I-131 MIBG imaging demonstrated significant resolution of tumors after external radiotherapy and chemotherapy. I-131 MIBG imaging is a simple, safe, and specific method of determining the location of tumors and also is clinically useful in the evaluation and management of patients with neuroblastoma.

Ikekubo, K.; Habuchi, Y.; Jeong, S.; Yamaguchi, H.; Saiki, Y.; Ito, H.; Hino, M.; Higa, T.

1986-11-01

213

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

214

Kilovoltage Imaging Doses in the Radiotherapy of Pediatric Cancer Patients  

SciTech Connect

Purpose: To investigate doses induced by kilovoltage cone-beam computed tomography (kVCBCT) to pediatric cancer patients undergoing radiotherapy, as well as strategies for dose reduction. Methods and Materials: An EGS4 Monte Carlo code was used to calculate three-dimensional dose deposition due to kVCBCT on 4 pediatric cancer patients. Absorbed doses to various organs were analyzed for both half-fan and full-fan modes. Clinical conditions, such as distance from organ at risk (OAR) to CBCT field border, kV peak energy, and testicular shielding, were studied. Results: The mean doses induced by one CBCT scan operated at 125 kV in half-fan mode to testes, liver, kidneys, femoral heads, spinal cord, brain, eyes, lens, and optical nerves were 2.9, 4.7, 7.7, 10.5, 8.8, 7.6, 7.7, 7.8, and 7.2 cGy, respectively. Increasing the distances from OARs to CBCT field border greatly reduced the doses to OARs, ranging from 33% reduction for spinal cord to 2300% reduction for testes. As photon beam energy increased from 60 to 125 kV, the dose increase due to kVCBCT ranged from 170% for lens to 460% for brain and spinal cord. A testicular shielding made of 1-cm cerrobend could reduce CBCT doses down to 31%, 51%, 68%, and 82%, respectively, for 60, 80, 100, and 125 kV when the testes lay within the CBCT field. Conclusions: Generally speaking, kVCBCT deposits much larger doses to critical structures in children than in adults, usually by a factor of 2 to 3. Increasing the distances from OARs to CBCT field border greatly reduces doses to OARs. Depending on OARs, kVCBCT-induced doses increase linearly or exponentially with photon beam energy. Testicular shielding works more efficiently at lower kV energies. On the basis of our study, it is essential to choose an appropriate scanning protocol when kVCBCT is applied to pediatric cancer patients routinely.

Deng Jun, E-mail: jun.deng@yale.edu [Department of Therapeutic Radiology, Yale University, New Haven, CT (United States); Chen Zhe; Roberts, Kenneth B.; Nath, Ravinder [Department of Therapeutic Radiology, Yale University, New Haven, CT (United States)

2012-04-01

215

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. PMID:25382845

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

2015-01-01

216

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

217

64-MDCT can depict the thrombi expanded from the left lower pulmonary vein to the left atrium in the patient with angina pectoris  

PubMed Central

Stroke is an important clinical problem and some strokes are caused by a cardiac thrombus. Although large thrombus in the left atrium (LA) is known, small-sized LA thrombus is rare. LA thrombus or a left atrial appendage (LAA) thrombus is well known to cause ischaemic stroke in patients with atrial fibrillation (AF). For patients with AF, anticoagulants are recommended to prevent stroke. 64-slice multidetector CT (64-MDCT) can estimate not only the coronary artery stenosis, but LAA thrombus and small pulmonary vein thrombus (PVT). This study demonstrated the thrombi in the left lower pulmonary vein to LA in a 70-year-old man without AF by 64-MDCT. The LA thrombi were identified by transthoracic echocardiography, the size of which was 30.2?mm×8.1?mm. PVT and the small LA thrombus seem to have been significantly underestimated. 64-MDCT is a useful tool to estimate PVT and LA thrombi promptly. PMID:23559655

Takeuchi, Hidekazu

2013-01-01

218

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

219

Model-based estimation of breast percent density in raw and processed full-field digital mammography images from image-acquisition physics and patient-image characteristics  

NASA Astrophysics Data System (ADS)

Breast percent density (PD%), as measured mammographically, is one of the strongest known risk factors for breast cancer. While the majority of studies to date have focused on PD% assessment from digitized film mammograms, digital mammography (DM) is becoming increasingly common, and allows for direct PD% assessment at the time of imaging. This work investigates the accuracy of a generalized linear model-based (GLM) estimation of PD% from raw and postprocessed digital mammograms, utilizing image acquisition physics, patient characteristics and gray-level intensity features of the specific image. The model is trained in a leave-one-woman-out fashion on a series of 81 cases for which bilateral, mediolateral-oblique DM images were available in both raw and post-processed format. Baseline continuous and categorical density estimates were provided by a trained breast-imaging radiologist. Regression analysis is performed and Pearson's correlation, r, and Cohen's kappa, ?, are computed. The GLM PD% estimation model performed well on both processed (r=0.89, p<0.001) and raw (r=0.75, p<0.001) images. Model agreement with radiologist assigned density categories was also high for processed (?=0.79, p<0.001) and raw (?=0.76, p<0.001) images. Model-based prediction of breast PD% could allow for a reproducible estimation of breast density, providing a rapid risk assessment tool for clinical practice.

Keller, Brad M.; Nathan, Diane L.; Conant, Emily F.; Kontos, Despina

2012-03-01

220

Patient dose considerations for routine megavoltage cone-beam CT imaging  

SciTech Connect

Megavoltage cone-beam CT (MVCBCT), the recent addition to the family of in-room CT imaging systems for image-guided radiation therapy (IGRT), uses a conventional treatment unit equipped with a flat panel detector to obtain a three-dimensional representation of the patient in treatment position. MVCBCT has been used for more than two years in our clinic for anatomy verification and to improve patient alignment prior to dose delivery. The objective of this research is to evaluate the image acquisition dose delivered to patients for MVCBCT and to develop a simple method to reduce the additional dose resulting from routine MVCBCT imaging. Conventional CT scans of phantoms and patients were imported into a commercial treatment planning system (TPS: Phillips, Pinnacle) and an arc treatment mimicking the MVCBCT acquisition process was generated to compute the delivered acquisition dose. To validate the dose obtained from the TPS, a simple water-equivalent cylindrical phantom with spaces for MOSFETs and an ion chamber was used to measure the MVCBCT image acquisition dose. Absolute dose distributions were obtained by simulating MVCBCTs of 9 and 5 monitor units (MU) on pelvis and head and neck patients, respectively. A compensation factor was introduced to generate composite plans of treatment and MVCBCT imaging dose. The article provides a simple equation to compute the compensation factor. The developed imaging compensation method was tested on routinely used clinical plans for prostate and head and neck patients. The quantitative comparison between the calculated dose by the TPS and measurement points on the cylindrical phantom were all within 3%. The dose percentage difference for the ion chamber placed in the center of the phantom was only 0.2%. For a typical MVCBCT, the dose delivered to patients forms a small anterior-posterior gradient ranging from 0.6 to 1.2 cGy per MVCBCT MU. MVCBCT acquisitions in the pelvis and head and neck areas deliver slightly more dose than current portal imaging but render soft tissue information for positioning. Overall, the additional dose from daily 9 MU MVCBCTs of prostate patients is small compared to the treatment dose (<4%). Dose-volume histograms of compensated plans for pelvis and head and neck patients imaged daily with MVCBCT showed no additional dose to the target and small increases at low doses. The results indicate that the dose delivered for MVCBCT imaging can be precisely calculated in the TPS and therefore included in the treatment plan. This allows simple plan compensations, such as slightly reducing the treatment dose, to minimize the total dose received by critical structures from daily positioning with MVCBCT. The proposed compensation factor reduces the number of MU per treatment beam per fraction. Both the number of fractions and the beam arrangement are kept unchanged. Reducing the imaging volume in the cranio-caudal direction can further reduce the dose delivered for MVCBCT. This is a useful feature to eliminate the imaging dose to the eyes or to focus on a specific region of interest for alignment.

Morin, Olivier; Gillis, Amy; Descovich, Martina; Chen, Josephine; Aubin, Michele; Aubry, Jean-Francois; Chen Hong; Gottschalk, Alexander R.; Xia Ping; Pouliot, Jean [Comprehensive Cancer Center, Department of Radiation Oncology, University of California San Francisco, San Francisco, California 94143 (United States) and UCSF/UC Berkeley Joint Graduate Group in Bioengineering, San Francisco, California 94158 (United States); Comprehensive Cancer Center, Department of Radiation Oncology, University of California San Francisco, San Francisco, California 94143 (United States); Comprehensive Cancer Center, Department of Radiation Oncology, University of California San Francisco, San Francisco, California 94143 (United States) and UCSF/UC Berkeley Joint Graduate Group in Bioengineering, San Francisco, California 94158 (United States)

2007-05-15

221

Expanding the Focus of Admissions Marketing Utility.  

ERIC Educational Resources Information Center

An expanded perspective for admissions marketing is suggested and examples of how such information can become a force for planning are provided. Implementing a broad-based program of information dissemination will better serve the prime interest groups of the university and enhance the image of professional admissions personnel. (MLW)

Lolli, Anthony; Scannell, James

1983-01-01

222

Improvement of the clinical use of computed radiography for mobile chest imaging: Image quality and patient dose  

NASA Astrophysics Data System (ADS)

Chest radiography is technically difficult because of the wide variation of tissue attenuations in the chest and limitations of screen-film systems. Mobile chest radiography, performed bedside on hospital inpatients, presents additional difficulties due to geometrical and equipment limitations inherent to mobile x-ray procedures and the severity of illness in patients. Computed radiography (CR) offers a new approach for mobile chest radiography by utilizing a photostimulable phosphor. Photostimulable phosphors are more efficient in absorbing lower-energy x-rays than standard intensifying screens and overcome some image quality limitations of mobile chest imaging, particularly because of the inherent latitude. This study evaluated changes in imaging parameters for CR to take advantage of differences between CR and screen-film radiography. Two chest phantoms, made of acrylic and aluminum, simulated x-ray attenuation for average-sized and large- sized adult chests. The phantoms contained regions representing the lungs, heart and subdiaphragm. Acrylic and aluminum disks (1.9 cm diameter) were positioned in the chest regions to make signal-to-noise ratio (SNR) measurements for different combinations of imaging parameters. Disk thicknesses (contrast) were determined from disk visibility. Effective dose to the phantom was also measured for technique combinations. The results indicated that using an anti-scatter grid and lowering x- ray tube potential improved the SNR significantly; however, the dose to the phantom also increased. An evaluation was performed to examine the clinical applicability of the observed improvements in SNR. Parameter adjustments that improved phantom SNRs by more than 50% resulted in perceived image quality improvements in the lung region of clinical mobile chest radiographs. Parameters that produced smaller improvements in SNR had no apparent effect on clinical image quality. Based on this study, it is recommended that a 3:1 grid be used for mobile chest radiography with CR in order to improve image quality. Using a higher kVp (+15 kVp) did not have a detrimental effect on image quality and offered a patient dose savings, including effective dose and breast dose. Higher kVp techniques should be considered when using a grid is not possible.

Rill, Lynn Neitzey

223

Diffusion tensor imaging of the brain in patients with Alzheimer’s disease and cerebrovascular lesions  

Microsoft Academic Search

Background  Recent autopsy study showed a high incidence of cerebrovascular lesions in Alzheimer’s disease (AD). To assess the impact\\u000a of cerebrovascular pathology in AD, we used diffusion tensor imaging (DTI) to study AD patients with and without cerebrovascular\\u000a lesions.\\u000a \\u000a \\u000a \\u000a Materials and Methods  Conventional and DTI scans were obtained from 10 patients with probable AD, 10 AD\\/V patients (probable AD with cerebrovascular\\u000a lesions)

Shao-qiong Chen; Zhuang Kang; Xi-quan Hu; Bing Hu; Yan Zou

2007-01-01

224

A retrospective analysis of negative diffusion-weighted image results in patients with acute cerebral infarction  

PubMed Central

We aimed to investigate the clinicoradiologic determinants of negative diffusion-weighted image (DWI) results in patients with acute cerebral infarction (ACI). The medical records were reviewed of ACI patients. Patients were divided to the DWI positive and negative group. Positive DWI was used as independent variable and patients' clinicoradiologic factors were used as co-variables for multivariate logistic regression analysis. 349 patients received initial cerebral MRI within 72?hours of admission. Lacunar infarction was most common (42.1%) followed by posterior circulation infarction (30.1%) and partial anterior circulation infarction (18.1%). The majority of the patients (72.2%) had an NIHSS score of less than 5 at admission. 316 patients (90.54%) were positive on initial DWI. Patients with smoking, initial SBP ? 140 or DBP ? 90?mmHg, initial fasting plasma glucose (FPG) ?7.0?mmol/L, initial MRI from onset of disease >1?d and anterior circulation infarction were liable to show positive DWI. Furthermore, DWI negative patients had significantly lower NIHSS scores (IQR 0,1,2) than DWI positive patients (IQR 1,2,4) (P = 0.000) at two weeks post onset of acute cerebral infarction. In conclusion, multiple clinicoradiologic factors are associated with negative and positive DWI and further delineation of these factors is required in future prospective studies. PMID:25777182

Zuo, Lian; Zhang, Yue; Xu, Xiahong; Li, Ying; Bao, Huan; Hao, Junjie; Wang, Xin; Li, Gang

2015-01-01

225

Dual energy CT in patients with acute abdomen; is it possible for virtual non-enhanced images to replace true non-enhanced images?  

PubMed

This study aims to determine whether virtual non-enhanced images derived from dual-energy computed tomography (CT) can replace true non-enhanced images in patients with acute abdomen. Patients with acute abdomen (n?=?202) underwent multidetector CT including non-enhanced and contrast-enhanced images obtained at the portal phase using the dual-energy technique. CT attenuation values were measured in abdominal organs. Image quality, noise, artifacts, and acceptability for virtual non-enhanced images compared to true non-enhanced images were rated. Mean sizes of clinically significant stones and mean attenuation values of intraabdominal hemorrhages were compared by means of five-point scales. Effective radiation doses were calculated. Mean CT attenuation values of virtual non-enhanced and true non-enhanced images were similar. Virtual non-enhanced images showed good image quality, mild noise, mild artifacts, and good acceptability compared to true non-enhanced images. A total of 71 clinically significant stones (11 appendicoliths, 33 gallbladder stones, 11 bile duct stones, and 16 urinary stones) and 15 intraabdominal hemorrhages were included in the study. Small stones were detected better on true non-enhanced images than on virtual non-enhanced images. Hemorrhage was similarly detected on both virtual non-enhanced and true non-enhanced images. Mean radiation dose reductions by omitting true non-enhanced images were 33 % in the virtual triple protocol and 47 % in the virtual dual protocol. Image qualities of virtual non-enhanced images are comparable to those of true non-enhanced images. Small stones can be obscured on virtual non-enhanced images. Therefore, tailored application of dual-energy CT is needed for evaluation of patients with acute abdomen. PMID:23821015

Im, A Lan; Lee, Young Hwan; Bang, Dong Ho; Yoon, Kwon Ha; Park, Sang Hyun

2013-12-01

226

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

E-print Network

1 Multi observation PET image analysis for patient follow-up quantitation and therapy assessment S Institut Telecom - Telecom Bretagne, Brest, F-29200 France. Abstract. In Positron Emission Tomography (PET-quantitative parameters restricted to maximum SUV measured in PET scans during the treatment. Such measurements do

Brest, Université de

227

Gated SPECT myocardial perfusion imaging in patients referred with isolated complaints of Dyspnea  

Microsoft Academic Search

Background: Dyspnea is a common indication for referral for cardiovascular stress testing. We sought to characterize the utility of gated SPECT stress perfusion imaging in patients referred because of a chief complaint of dyspnea. In this group comorbidities included cad 22%, hyperternsion 74%, hyperlipidemia 49%, diabetes 38%, chf 20%, copd 17%.Methods: a total of 89 consecutive (66 ± 13 yrs)

M. D Greenberg; F Liu; O Frankenberger; P Kokkinos; D Hanumara; E Goheen; C Wu; D Panagiotakos; R Fletcher

2004-01-01

228

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

229

Tc99m HMPAO brain perfusion imaging in young Down's syndrome patients  

Microsoft Academic Search

Down's syndrome (DS) is characterized by moderate mental retardation and a variety of abnormalities involving multiple organ systems. There is a high incidence of Alzheimer's disease (AD) type dementia beyond the age of 35. In this study, single photon emission computed tomography (SPECT) brain perfusion imaging of young Down's syndrome patients was performed to define the perfusion pattern. Tc-99m HMPAO

Nahide Gökçora; Tamer Atasever; Ne?e ?lgin Karabacak; Gülin Vural; K?v?lc?m Gücüyener

1999-01-01

230

Renal uptake of Tl-201 in hypertensive patients undergoing myocardial perfusion imaging  

SciTech Connect

The detection of renovascular disease (RVD) has particular relevance in hypertensive patients (HP) who have symptoms of target organ damage. To evaluate the possibility of RVD in HP undergoing myocardial perfusion scintigraphy for chest pain symptoms, posterior renal images were obtained at 1-3 hours after Tl-201 injection. Analog and computer images were obtained for 5 minutes in 45 HP; 12 patients with no history of hypertension or renal disease served as normal controls. For qualitative analysis, images were coded and read by three observers as to symmetry of renal uptake. Differential renal uptake of Tl-201 (DRU) was quantitated on computer images. In normal controls, uptake was agreed on as symmetric. In HP, 6 patients had marked asymmetry of DRU and 4 had possibly significant asymmetry; 2 had decreased uptake in both kidneys suggesting bilateral RVD or nephrosclerosis. Objective correlation with DRU was obtained in 10 HP who had contrast angiography, confirming 4 cases of unilateral RVD and 2 of bilateral RVD. Thirteen patients also had renography with Tc-99m DTPA; differential renal function by this modality correlated well with DRU of Tl-201 (r = 0.98). Thus, DRU of Tl-201 can be used as a supplement to myocardial scintigraphy to identify HP who require further evaluation and treatment of RVD.

Hurwitz, G.A.; Mattar, A.G.; Bhargava, R.; Driedger, A.A.; Hogendoorn, P.; Wesolowski, C.A. (Univ. of Western Ontario, London (Canada))

1990-02-01

231

Texture analysis of MR images of patients with Mild Traumatic Brain Injury  

Microsoft Academic Search

BACKGROUND: Our objective was to study the effect of trauma on texture features in cerebral tissue in mild traumatic brain injury (MTBI). Our hypothesis was that a mild trauma may cause microstructural changes, which are not necessarily perceptible by visual inspection but could be detected with texture analysis (TA). METHODS: We imaged 42 MTBI patients by using 1.5 T MRI

Kirsi K Holli; Lara Harrison; Prasun Dastidar; Minna Wäljas; Suvi Liimatainen; Tiina Luukkaala; Juha Öhman; Seppo Soimakallio; Hannu Eskola

2010-01-01

232

Modulation of brain response to emotional images by alcohol cues in alcohol-dependent patients  

Microsoft Academic Search

Alcohol is often used to modulate mood states. Alcohol drinkers report that they use alcohol both to enhance positive affect and to reduce dysphoria, and alcohol-dependent patients specifically state reduction of negative affect as a primary reason for drinking.The current study proposes that alcohol cues may reduce negative affect in alcoholics. We used functional magnetic resonance imaging to examine brain

Jodi M. Gilman; Daniel W. Hommer

2008-01-01

233

Magnetic resonance imaging of the pituitary gland in patients with secondary hypogonadism due to transfusional hemochromatosis.  

PubMed

To identify pituitary iron overload in patients with transfusional hemochromatosis causing secondary hypogonadism, we prospectively evaluated signal intensity abnormalities of the anterior lobe of the pituitary gland of 18 patients affected by transfusion-dependent thalassemia major and secondary hypogonadism. Magnetic resonance (MR) imaging is useful to assess pituitary iron overload in patients with transfusional hemochromatosis and secondary hypogonadism by detection of a significant decreased signal intensity of the anterior lobe of the pituitary gland on GRE T2*-weighted images. The decreased signal intensity of the anterior lobe of the pituitary gland on GRE T2*-weighted images was correlated to increasing serum ferritin level (r = -0.84, r2 = -0.70, P < 0.001). Indeed, the lower the signal intensity of the pituitary gland, the greater the serum ferritin level. However an exact quantification of pituitary iron overload by correlation with serum ferritin level is not allowed. No correlation was found between MR imaging results and hormonal status; however, the detection of pituitary iron overload on GRE T2*-weighted images is consistent with the hypothesis of hypogonadotrophic pituitary insufficiency due to iron-induced cellular damage. PMID:10456370

Sparacia, G; Midiri, M; D'Angelo, P; Lagalla, R

1999-05-01

234

Expanding the Literary Canon  

ERIC Educational Resources Information Center

For most college students, literature courses began in high school and consisted almost entirely of the classics of America and Western Europe. English professor Norma E. Cantu says the emergence of Hispanic literature and its growing popularity on college campuses around the country--and the world--is proof that American literature is expanding

Horwedel, Dina

2007-01-01

235

EXPANDED BED BIOLOGICAL TREATMENT  

EPA Science Inventory

A three-year pilot-scale research investigation at the EPA Lebanon Pilot Plant was conducted to evaluate the feasibility of a unique biological secondary treatment process, designated the Expanded Bed Biological Treatment Process (EBBT). The EBBT process is a three-phase (oxygen/...

236

Expanding the Mainstream  

Microsoft Academic Search

HE NOTION of expanding the mainstream assumes a main- stream; but in thinking about and talking with colleagues about this paper, the primary question that arose was, whose main- stream? Over the past four years, while I was preparing the exhibition The Art of Romare Bearden for the National Gallery of Art, Washing- ton, D.C., it became increasingly clear to

RUTH FINE

2005-01-01

237

An expanded servicescape perspective  

Microsoft Academic Search

Purpose – The purpose of this paper is to put forth an expanded servicescape framework that shows that a perceived servicescape comprises physical, social, socially symbolic, and natural environmental dimensions. Design\\/methodology\\/approach – This conceptual paper offers an in-depth literature review on servicescape topics from a variety of disciplines, both inside and outside marketing, to advance a logical framework built on

Mark S. Rosenbaum; Carolyn Massiah

2011-01-01

238

Centrifugal piston expander  

Microsoft Academic Search

The improved method and apparatus for operating a centrifugal piston expander of the type wherein a free piston is mounted in a rotating fluid pressure chamber having a longitudinal axis that is non-radial with respect to the axis of rotation, but extends from a position remote from the rotation axis to a position proximate to the rotation axis. To bring

Dibrell

1985-01-01

239

Cryogenic expander recovery process  

Microsoft Academic Search

A process is described for treating a gaseous hydrocarbon-containing feed stream such as natural gas or refinery gas to leave the ethane in the hydrocarbon gaseous stream and to separate and recover the Câ and heavier hydrocarbon components. Increased recovery is achieved with the expenditure of less power by expanding the hydrocarbon gaseous feed stream in a cryogenic expansion step

J. D. Hammond; E. H. Deng

1981-01-01

240

Circulating CD56dim 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

241

Role of Sodium Fluoride PET Imaging for Identification of Bony Metastases in Prostate Cancer Patients.  

PubMed

Sodium fluoride (Na-F) PET/CT is an imaging technique which allows radiolabeled fluoride to help detect areas of bone turnover. Detecting metastatic prostate cancer earlier than is currently possible with standard imaging may help prevent unnecessary morbidity for patients and improve staging in an effort to more accurately select the appropriate therapy at an appropriate time. Na-F PET/CT has been investigated as a means to help detect osseous metastatic disease in prostate cancer. It is still unclear which clinical circumstances are beneficial for a patient to undergo Na-F PET/CT in addition to, or instead of, the current standard imaging. This review examines the most recent publications related to this topic. PMID:25794498

Hughes, C Tanner; Nix, Jeffrey Wells

2015-05-01

242

Clinical findings and imaging features of 67 nasopharyngeal carcinoma patients with postradiation nasopharyngeal necrosis  

PubMed Central

Postradiation nasopharyngeal necrosis is an important late effect of radiotherapy that affects prognosis in patients with nasopharyngeal carcinoma. In the present study, we reviewed the clinical and imaging features of 67 patients with pathologically diagnosed postradiation nasopharyngeal necrosis who were treated at Sun Yat-sen University Cancer Center between June 2006 and January 2010. Their clinical manifestations, endoscopic findings, and imaging features were analyzed. Early nasopharyngeal necrosis was limited to a local site in the nasopharyngeal region, and the tissue defect was not obvious, whereas deep parapharyngeal ulcer or signs of osteoradionecrosis in the basilar region was observed in serious cases. Those with osteoradionecrosis and/or exposed carotid artery had a high mortality. In conclusion, Postradiation nasopharyngeal necrosis has characteristic magnetic resonance imaging appearances, which associate well with clinical findings, but pathologic examination is essential to make the diagnosis. PMID:23816556

Chen, Ming-Yuan; Mai, Hai-Qiang; Sun, Rui; Guo, Xiang; Zhao, Chong; Hong, Ming-Huang; Hua, Yi-Jun

2013-01-01

243

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

244

The Role of Magnetic Resonance Imaging in Preoperative Planning for Patients Undergoing Therapeutic Mammoplasty  

PubMed Central

Background. Assessment of the ratio between tumour volume and breast volume in therapeutic mammoplasty is paramount. Traditionally based on clinical assessment and conventional breast imaging, the role of breast magnetic resonance imaging (MRI) in this context has not been established. Methods. Data was collected from all women undergoing therapeutic mammoplasty (TM) between 2006 and 2011. Each case was discussed at an MDT where MRI was considered to facilitate surgical planning. The contribution of MRI to disease assessment and surgical outcome was then reviewed. Results. 35 women underwent TM, 15 of whom had additional MRI. 33% of patients within the MRI subgroup had abnormalities not seen on either mammography or USS. Of those undergoing MRI, 1/15 patients required completion mastectomy versus 3 patients requiring completion mastectomy and 1 patient requiring further wide local excision (4/20) in the conventional imaging group. No statistical difference was seen between size on MRI and size on mammography versus final histological size, but a general trend for greater correlation between size on MRI and final histological size was seen. Conclusion. MRI should be considered in selected patients undergoing therapeutic mammoplasty. Careful planning can identify those who are most likely to benefit from MRI, potentially reducing the need for further surgery. PMID:24455305

Turton, Philip; Rajan, Sree; Nunn, April; Sharma, Nisha; Achuthan, Raj

2013-01-01

245

Magnetic resonance imaging in patients with cardiac pacemakers: era of "MR Conditional" designs.  

PubMed

Advances in cardiac device technology have led to the first generation of magnetic resonance imaging (MRI) conditional devices, providing more diagnostic imaging options for patients with these devices, but also new controversies. Prior studies of pacemakers in patients undergoing MRI procedures have provided groundwork for design improvements. Factors related to magnetic field interactions and transfer of electromagnetic energy led to specific design changes. Ferromagnetic content was minimized. Reed switches were modified. Leads were redesigned to reduce induced currents/heating. Circuitry filters and shielding were implemented to impede or limit the transfer of certain unwanted electromagnetic effects. Prospective multicenter clinical trials to assess the safety and efficacy of the first generation of MR conditional cardiac pacemakers demonstrated no significant alterations in pacing parameters compared to controls. There were no reported complications through the one month visit including no arrhythmias, electrical reset, inhibition of generator output, or adverse sensations. The safe implementation of these new technologies requires an understanding of the well-defined patient and MR system conditions. Although scanning a patient with an MR conditional device following the strictly defined patient and MR system conditions appears straightforward, issues related to patients with pre-existing devices remain complex. Until MR conditional devices are the routine platform for all of these devices, there will still be challenging decisions regarding imaging patients with pre-existing devices where MRI is required to diagnose and manage a potentially life threatening or serious scenario. A range of other devices including ICDs, biventricular devices, and implantable physiologic monitors as well as guidance of medical procedures using MRI technology will require further biomedical device design changes and testing. The development and implementation of cardiac MR conditional devices will continue to require the expertise and collaboration of multiple disciplines and will need to prove safety, effectiveness, and cost effectiveness in patient care. PMID:22032338

Shinbane, Jerold S; Colletti, Patrick M; Shellock, Frank G

2011-01-01

246

Essential pre-treatment imaging examinations in patients with endoscopically-diagnosed early gastric cancer  

PubMed Central

Background There have been no reports discussing which imaging procedures are truly necessary before treatment of endoscopically-diagnosed early gastric cancer (eEGC). The aim of this pilot study was to show which imaging examinations are essential to select indicated treatment or appropriate strategy in patients with eEGC. Methods In 140 consecutive patients (95 men, 45 women; age, 66.4 +/- 11.3 years [mean +/- standard deviation], range, 33-90) with eEGC which were diagnosed during two years, the pre-treatment results of ultrasonography (US) and contrast-enhanced computed tomography (CT) of the abdomen, barium enema (BE) and chest radiography (CR) were retrospectively reviewed. Useful findings that might affect indication or strategy were evaluated. Results US demonstrated useful findings in 13 of 140 patients (9.3%): biliary tract stones (n = 11) and other malignant tumors (n = 2). Only one useful finding was demonstrated on CT (pancreatic intraductal papillary mucinous tumor) but not on US (0.7%; 95% confidential interval [CI], 2.1%). BE demonstrated colorectal carcinomas in six patients and polyps in 10 patients, altering treatment strategy (11.4%; 95%CI, 6.1-16.7%). Of these, only two colorectal carcinomas were detected on CT. CR showed three relevant findings (2.1%): pulmonary carcinoma (n = 1) and cardiomegaly (n = 2). Seventy-nine patients (56%) were treated surgically and 56 patients were treated by endoscopic intervention. The remaining five patients received no treatment due to various reasons. Conclusions US, BE and CR may be essential as pre-treatment imaging examinations because they occasionally detect findings which affect treatment indication and strategy, although abdominal contrast-enhanced CT rarely provide additional information. PMID:20534137

2010-01-01

247

Balancing dose and image registration accuracy for cone beam tomosynthesis (CBTS) for breast patient setup  

SciTech Connect

Purpose: To balance dose reduction and image registration accuracy in breast setup imaging. In particular, the authors demonstrate the relationship between scan angle and dose delivery for cone beam tomosynthesis (CBTS) when employed for setup verification of breast cancer patients with surgical clips. Methods: The dose measurements were performed in a female torso phantom for varying scan angles of CBTS. Setup accuracy was measured using three registration methods: Clip centroid localization accuracy and the accuracy of two semiautomatic registration algorithms. The dose to the organs outside of the ipsilateral breast and registration accuracy information were compared to determine the optimal scan angle for CBTS for breast patient setup verification. Isocenter positions at the center of the patient and at the breast-chest wall interface were considered. Results: Image registration accuracy was within 1 mm for the CBTS scan angles {theta} above 20 deg. for some scenarios and as large as 80 deg. for the worst case, depending on the imaged breast and registration algorithm. Registration accuracy was highest based on clip centroid localization. For left and right breast imaging with the isocenter at the chest wall, the dose to the contralateral side of the patient was very low (<0.5 cGy) for all scan angles considered. For central isocenter location, the optimal scan angles were 30 deg. - 50 deg. for the left breast imaging and 40 deg. - 50 deg. for the right breast imaging, with the difference due to the geometric asymmetry of the current clinical imaging system. Conclusions: The optimal scan angles for CBTS imaging were found to be between 10 deg. and 50 deg., depending on the isocenter location and ipsilateral breast. Use of the isocenter at the breast-chest wall locations always resulted in greater accuracy of image registration (<1 mm) at smaller angles (10 deg. - 20 deg.) and at lower doses (<0.1 cGy) to the contralateral organs. For chest wall isocenters, doses delivered to organs outside of the target breast were much smaller than the scattered and leakage doses of the treatment beams. The complete volumetric information of all clips in the region of interest, combined with the small dose to the contralateral organs and the small scan angle, could result in an advantage for small angle CBTS with off center isocenters over simple orthogonal pairs.

Winey, B. A.; Zygmanski, P.; Cormack, R. A.; Lyatskaya, Y. [Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center, Harvard Medical School, Boston, Massachusetts 02115 (United States)

2010-08-15

248

Image-guided radiotherapy for cardiac sparing in patients with left-sided breast cancer.  

PubMed

Patients with left-sided breast cancer are at risk of cardiac toxicity because of cardiac irradiation during radiotherapy with the conventional 3-dimensional conformal radiotherapy technique. In addition, many patients may receive chemotherapy prior to radiation, which may damage the myocardium and may increase the potential for late cardiac complications. New radiotherapy techniques such as intensity-modulated radiotherapy (IMRT) may decrease the risk of cardiac toxicity because of the steep dose gradient limiting the volume of the heart irradiated to a high dose. Image-guided radiotherapy (IGRT) is a new technique of IMRT delivery with daily imaging, which may further reduce excessive cardiac irradiation. Preliminary results of IGRT for cardiac sparing in patients with left-sided breast cancer are promising and need to be investigated in future prospective clinical studies. PMID:25295227

Lemanski, Claire; Thariat, Juliette; Ampil, Federico L; Bose, Satya; Vock, Jacqueline; Davis, Rick; Chi, Alexander; Dutta, Suresh; Woods, William; Desai, Anand; Godinez, Juan; Karlsson, Ulf; Mills, Melissa; Nguyen, Nam Phong; Vinh-Hung, Vincent

2014-01-01

249

Image-Guided Radiotherapy for Cardiac Sparing in Patients with Left-Sided Breast Cancer  

PubMed Central

Patients with left-sided breast cancer are at risk of cardiac toxicity because of cardiac irradiation during radiotherapy with the conventional 3-dimensional conformal radiotherapy technique. In addition, many patients may receive chemotherapy prior to radiation, which may damage the myocardium and may increase the potential for late cardiac complications. New radiotherapy techniques such as intensity-modulated radiotherapy (IMRT) may decrease the risk of cardiac toxicity because of the steep dose gradient limiting the volume of the heart irradiated to a high dose. Image-guided radiotherapy (IGRT) is a new technique of IMRT delivery with daily imaging, which may further reduce excessive cardiac irradiation. Preliminary results of IGRT for cardiac sparing in patients with left-sided breast cancer are promising and need to be investigated in future prospective clinical studies. PMID:25295227

Lemanski, Claire; Thariat, Juliette; Ampil, Federico L.; Bose, Satya; Vock, Jacqueline; Davis, Rick; Chi, Alexander; Dutta, Suresh; Woods, William; Desai, Anand; Godinez, Juan; Karlsson, Ulf; Mills, Melissa; Nguyen, Nam Phong; Vinh-Hung, Vincent

2014-01-01

250

Dynamic aspects of expanding cava septi pellucidi et Vergae.  

PubMed

Two paediatric patients with expanding cysts of the cava Vergae et septi pellucidi are presented. In the first patient, consecutive CT scans showed a growing cavum thought to be responsible for his dramatic increase in head circumference. In the other patient, the expanding cavum was discovered because a routine skull X-ray after minor head trauma revealed marked impressiones digitatae. Both patients were successfully treated with stereotactically placed internal shunts from the cysts via the lateral ventricle to the subarachnoid space. During this procedure, contrast medium was instilled, and the cysts were visualized on postoperative CT scans. Some dynamic aspects of such expanding cava are discussed. PMID:2251944

Wester, K; Pedersen, P H; Larsen, J L; Waaler, P E

1990-01-01

251

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

252

Radioimmune imaging of bone marrow in patients with suspected bone metastases from primary breast cancer  

SciTech Connect

Radioimmune imaging of bone marrow was performed by technetium-99m- (99mTc) labeled antigranulocyte monoclonal antibody BW 250/183 (AGMoAb) scans in 32 patients with suspected bone metastases from primary breast cancer. AGMoAb scans showed bone marrow defects in 25/32 (78%) patients; bone invasion was subsequently confirmed in 23 (72%) patients. Conventional bone scans performed within the same week detected bone metastases in 17/32 (53%) patients (p less than 0.001). AGMoAb scans detected more sites indicating metastatic disease than bone scans in 12 of these 17 patients (71%). All patients with bone metastases in the axial skeleton had bone marrow defects at least at the sites of bone metastases. Of 15 patients with normal, or indicative of, benign disease bone scans, 8 patients (53%) presented with bone marrow defects in the AGMoAb scans. Bone invasion was confirmed in six of them. AGMoAb bone marrow scans provide a method for the early detection of bone metastatic invasion in patients with breast cancer and suspected bone metastases.

Duncker, C.M.; Carrio, I.; Berna, L.; Estorch, M.; Alonso, C.; Ojeda, B.; Blanco, R.; Germa, J.R.; Ortega, V. (Hospital de Sant Pau, Barcelona (Spain))

1990-09-01

253

Patient-specific CT dose determination from CT images using Monte Carlo simulations  

NASA Astrophysics Data System (ADS)

Radiation dose from computed tomography (CT) has become a public concern with the increasing application of CT as a diagnostic modality, which has generated a demand for patient-specific CT dose determinations. This thesis work aims to provide a clinically applicable Monte-Carlo-based CT dose calculation tool based on patient CT images. The source spectrum was simulated based on half-value layer measurements. Analytical calculations along with the measured flux distribution were used to estimate the bowtie-filter geometry. Relative source output at different points in a cylindrical phantom was measured and compared with Monte Carlo simulations to verify the determined spectrum and bowtie-filter geometry. Sensitivity tests were designed with four spectra with the same kVp and different half-value layers, and showed that the relative output at different locations in a phantom is sensitive to different beam qualities. An mAs-to-dose conversion factor was determined with in-air measurements using an Exradin A1SL ionization chamber. Longitudinal dose profiles were measured with thermoluminescent dosimeters (TLDs) and compared with the Monte-Carlo-simulated dose profiles to verify the mAs-to-dose conversion factor. Using only the CT images to perform Monte Carlo simulations would cause dose underestimation due to the lack of a scatter region. This scenario was demonstrated with a cylindrical phantom study. Four different image extrapolation methods from the existing CT images and the Scout images were proposed. The results show that performing image extrapolation beyond the scan region improves the dose calculation accuracy under both step-shoot scan mode and helical scan mode. Two clinical studies were designed and comparisons were performed between the current CT dose metrics and the Monte-Carlo-based organ dose determination techniques proposed in this work. The results showed that the current CT dosimetry failed to show dose differences between patients with the same scan parameters. The methodology proposed in this work required simple measurements on the CT scanner for scanner-specific Monte Carlo model establishment, and uses patient CT images to provide patient-specific organ dose calculations. This is an improvement on current CT dosimetry and benefits the patient dose tracking and individual risk estimates.

Liang, Qing

254

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

255

Tomographic and planar radionuclide imaging in patients suspected meniscal injury: Arthroscopic correlation  

SciTech Connect

In patients (pts) with knee pain which may be related to meniscal tears, clinical judgment is used to determine whether medical management or arthroscopy is indicated. Based on the assumption that meniscal injury will result in adjacent changes in Tc-99m MDP bone images, studies using both planar and tomographic techniques were performed in 12 pts referred for arthroscopy. Planar imaging was performed in the anterior, posterior, and posterior medial and lateral oblique positions of the symptomatic knee. Single photon emission computed tomography was performed using a 64 view 360/sup 0/ acquisition of both knees. In this series, both imaging techniques were accurate in identifying abnormality, but analysis of transaxial tomographic data showed greater contrast and facilitated localization because of the better spatial orientation provided by this method. Thus, tomographic bone imaging appears valuable in defining areas of localized abnormality in the knees of pts with meniscal injury.

Fajman, W.A.; Diehl, M.; Dunaway, E.; Stephenson, R.; Eisner, R.; Riggins, R.S.; Berger, H.J.

1985-05-01

256

Reconstruction of patient-specific femurs using X-ray and sparse CT images.  

PubMed

Three-dimensional patient-specific bone models have been used in computer-aided planning and biomechanical analysis of orthopaedic surgeries. Reconstruction methods using X-ray images have been developed recently. However, these reconstruction methods have limited ability to generate femur models with severe rotational deformities. In this study, a new X-ray-based reconstruction method was proposed using the free form deformation method with two X-ray images and three CT images. The obtained femur model is closer to a CT-based 3D femur model in comparison with the reconstruction method using only X-ray images. This method will have benefits for many clinical and biomechanical applications. PMID:21641590

Koh, Kyung; Kim, Yoon Hyuk; Kim, Kyungsoo; Park, Won Man

2011-07-01

257

Thallium-201 versus technetium-99m pyrophosphate myocardial imaging in detection and evaluation of patients with acute myocardial infarction  

SciTech Connect

Thallium-201 myocardial imaging is of value in the early detection and evaluation of patients with suspected acute infarction. Thallium imaging may have a special value in characterizing patients with cardiogenic shock and in detecting patients at risk for subsequent infarction or death or death or both, before hospital discharge. Approximately 95 percent of pateints with transmural or nontransmural myocardial infarction can be detected with technetium-99m pyrophosphate myocardial imaging if the imaging is performed 24 to 72 hours after the onset of symptoms. Pyrophosphate imaging may have an important role in the evaluation of patients during the early follow-up period after hospital discharge from an episode of acute infarction. The finding of a persistently positive pyrophosphate image suggests a poor prognosis and is associated with a relatively large incidence of subsequent myocardial infarction and death.

Pitt, B.; Thrall, J.H.

1980-12-18

258

Magnetic resonance imaging in patients with newly diagnosed breast cancer: a review of the literature.  

PubMed

The use of magnetic resonance imaging (MRI) in patients with newly diagnosed breast cancer remains controversial. Here we review the current use of breast MRI and the impact of MRI on short-term surgical outcomes and rates of local recurrence. In addition, we address the use of MRI in specific patient populations, such as those with ductal carcinoma in situ, invasive lobular carcinoma, and occult primary breast cancer, and discuss the potential role of MRI for assessing response to neoadjuvant chemotherapy. Although MRI has improved sensitivity compared with conventional imaging, this has not translated into improved short-term surgical outcomes or long-term patient benefit, such as improved local control or survival, in any patient population. MRI is an important diagnostic test in the evaluation of patients presenting with occult primary breast cancer and has shown promise in monitoring response to neoadjuvant chemotherapy; however, the data do not support the routine use of perioperative MRI in patients with newly diagnosed breast cancer. Cancer 2014;120:120:2080-2089. © 2014 American Cancer Society. PMID:24752817

Pilewskie, Melissa; King, Tari A

2014-07-15

259

What Does PET Imaging Add to Conventional Staging of Head and Neck Cancer Patients?  

SciTech Connect

Purpose: To determine the value of PET scans in the staging of patients with head and neck carcinoma. Methods and Materials: The charts of 25 patients who underwent neck dissection, computed tomography (CT) scan, and F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging as part of their initial work-up for a head and neck squamous cell cancer between 2000-2003 were reviewed. All patients underwent clinical examination, triple endoscopy, and chest radiograph as part of their clinical staging, adhering to American Joint Commission for Cancer criteria. In addition to the clinical nodal (N) stage, PET findings were incorporated to determine a second type of N staging: clinical N + PET stage. The number of neck sides and nodal levels involved on CT or PET and on pathologic examination were recorded. Results: The sensitivity and specificity for detection of nodal disease were similar for CT and FDG-PET. Positive and negative likelihood ratios were similar for both diagnostic tests. None of our 25 patients had unsuspected distant disease detected by PET. Conclusion: The addition of PET imaging did not improve diagnostic accuracy in our patients compared with CT. PET scanning did not alter clinical management in any of the patients.

Pohar, Surjeet [Department of Radiation Oncology, SUNY Upstate Medical University, Syracuse, NY (United States) and Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA (United States)]. E-mail: poharss@evms.edu; Brown, Robert B.S. [Department of Radiation Oncology, SUNY Upstate Medical University, Syracuse, NY (United States); Newman, Nancy [Department of Medicine, SUNY Upstate Medical University, Syracuse, NY (United States); Koniarczyk, Michael [Department of Radiation Oncology, SUNY Upstate Medical University, Syracuse, NY (United States); Hsu, Jack [Department of Otolaryngology, SUNY Upstate Medical University, Syracuse, NY (United States); Feiglin, David [Department of Radiology, SUNY Upstate Medical University, Syracuse, NY (United States)

2007-06-01

260

PRACTICAL PARALLEL IMAGING COMPRESSED SENSING MRI: SUMMARY OF TWO YEARS OF EXPERIENCE IN ACCELERATING BODY MRI OF PEDIATRIC PATIENTS.  

E-print Network

years1 , we have been experimenting with ap- plying compressed sensing parallel imaging for body imagPRACTICAL PARALLEL IMAGING COMPRESSED SENSING MRI: SUMMARY OF TWO YEARS OF EXPERIENCE IN ACCELERATING BODY MRI OF PEDIATRIC PATIENTS. SS Vasanawala2 MJ Murphy 1 MT Alley2 P Lai3 K Keutzer1 JM Pauly4 M

Lustig, Michael 'Miki'

261

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

PubMed Central

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 optimisation 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 7.5mm 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 75kV and 120kV. 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 × 6.1cm2, yielding doses of 406mGy and 185mGy over the course of an IMRT treatment for 75kV (10 mAs) and 120kV (1.04 mAs) imaging, respectively at 1Hz. 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 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

2012-01-01

262

Imaging observations of pulmonary inflammatory myofibroblastic tumors in patients over 40 years old  

PubMed Central

Pulmonary inflammatory myofibroblastic tumors (PIMTs) are extremely rare in adults. If occurring in patients >40 years old, PIMT should be rapidly distinguished from lung cancer. The present study aimed to characterize the imaging features of PIMT in patients >40 years old in order to improve the diagnosis of PIMT. The imaging data of 10 patients with PIMT were reviewed retrospectively. Of the patients, eight underwent computed tomography (CT), two underwent positron emission tomography (PET)/CT and four underwent single-photon emission computed tomography (SPECT). Unenhanced CT revealed 10 lesions with a maximum diameter ranging between 5 and 57 mm located in the lower (n=6) or upper (n=4) lobe, in a peripheral (n=9) or central (n=1) region, and that were well- (n=4) or ill-defined (n=6), and round to oval (n=5) or irregular (n=5) in shape. Calcification (n=3), necrosis (n=6), cavity (n=4), air bronchogram (n=6) and obstructive pneumonia (n=1) were also observed in the patients. Contrast-enhanced CT revealed six lesions with moderate to high contrast enhancement in the arterial and venous phases, including four lesions with delayed enhancement. PET/CT identified two lesions with increased tracer uptake that were homogeneous and heterogeneous and each exhibited a maximal standard uptake value (SUVmax) of 6.0 and 5.4, respectively. The delayed PET/CT revealed foci that each exhibited an increased SUVmax of 6.9 and 5.9, respectively. SPECT demonstrated no definitive bone metastases, but did reveal atypical hypertrophic pulmonary osteoarthropathy in one patient. The combined imaging methods may lead to a more precise evaluation of PIMT in patients >40 years old. PMID:25789060

WU, JIANG; ZHU, HONG; LI, KAI; YUAN, CAI-YUN; WANG, YAN-FEN; LU, GUANG-MING

2015-01-01

263

Infrared Thermal Imaging in Patients with Medial Collateral Ligament Injury of the Knee - A Retrospective Study  

PubMed Central

Objectives: Digital infrared thermographic imaging (DITI) has been used widely for various inflammatory diseases, circulatory diseases, skin diseases, musculoskeletal diseases and cancers. In cases of ligament injury, obviously the temperature of the damaged area increases due to local inflammation; however, whether the temperature also increases due to DITI has not been determined. The purpose of the present study was to identify whether or not the changes of temperature in patient’s with medial collateral ligament injury were really due to infrared thermography and to determine the applicability of DITI for assessing ligament injuries. Methods: Twenty patient’s who underwent DITI for a medial collateral ligament injury from September 2012 to June 2014 were included in the current study. The thermographic images from the patient’s knees were divided to cover seven sub-areas: the middle of the patella, and the inferomedial, the inferolateral, the superomedial, the superolateral, the medial, and the lateral regions of patella. The temperatures of the seven regions were measured, and the temperature differences between affected and unaffected regions were analyzed by using the Wilcoxon signed rank test. Results: The 20 patient’s were composed of 14 women (70%) and 6 men (30%), with a mean age of 62.15 ± 15.71 (mean ± standard deviation (SD)) years. The temperature of the affected side, which included the middle of the patella, and the inferomedial, the superomedial, the superolateral, and the medial regions, showed a significant increase compared to that of the unaffected side (P < 0.05). The inferolateral and the lateral regions showed no significant changes. Conclusion: Our study results suggest that DITI can show temperature changes if a patient has a ligament injury and that it can be applied in the evaluation of a medial collateral ligament injury. PMID:25780719

Yang, HyunJung; Park, HaeIn; Lim, Chungsan; Park, SangKyun; Lee, KwangHo

2014-01-01

264

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

265

Expandable LED array interconnect  

DOEpatents

A light emitting device that can function as an array element in an expandable array of such devices. The light emitting device comprises a substrate that has a top surface and a plurality of edges. Input and output terminals are mounted to the top surface of the substrate. Both terminals comprise a plurality of contact pads disposed proximate to the edges of the substrate, allowing for easy access to both terminals from multiple edges of the substrate. A lighting element is mounted to the top surface of the substrate. The lighting element is connected between the input and output terminals. The contact pads provide multiple access points to the terminals which allow for greater flexibility in design when the devices are used as array elements in an expandable array.

Yuan, Thomas Cheng-Hsin; Keller, Bernd

2011-03-01

266

The Expanding Place Value  

NSDL National Science Digital Library

This collection of three lesson plans is designed to provide students with practice understanding place value (0 to 999), using standard and word form to represent numbers, and using expanded form to represent place value. Each lesson plan provides activities that will help build student understanding of the concepts and practice to help reinforce the skill. Thirteen resource sheets are included and can be used with these lessons or as independent activities.

Erin Thomson

2005-01-01

267

[Development of an automated patient recognition method for chest CT images using a template-matching technique].  

PubMed

If patient information, such as identification number or patient name, has been entered incorrectly in a picture archiving and communication system (PACS) environment, the image may be stored in the wrong place. To prevent such cases of misfiling, we have developed an automated patient recognition system for chest CT images. The image database consisted of 100 cases with present and previous chest CT images. A volume of interest (VOI) measuring 40 × 40 pixels was selected from the left lung region, bronchus region, and right lung region. Next, the overall lung region and these three regions in a current chest CT image were used as a template for determining the residual value with the corresponding four regions in previous chest CT images. To ensure separation between the same and different patients, we applied a combined analysis that employed the ruled-based plus artificial neural network (ANN) method. The overall performance of the method developed was examined in terms of receiver operating characteristic (ROC) curves. The performance of the rule-based plus ANN method using a combination of the four regions was higher than obtained using a rule-based method using these four regions separately. The automated patient recognition system using the rule-based plus ANN method achieved an area under the curve (AUC) value of 0.987. This automated patient recognition method for chest CT images is promising for helping to retrieve misfiled patient images, especially in a PACS environment. PMID:25327422

Okumura, Eiichiro; Aridome, Kazushige; Iwakiri, Chika; Oda, Kenji; Nakamura, Keita; Yamamoto, Masateru

2014-10-01

268

IVUS Validation of Patient Coronary Artery Lumen Area Obtained from CT Images  

PubMed Central

Aims Accurate computed tomography (CT)-based reconstruction of coronary morphometry (diameters, length, bifurcation angles) is important for construction of patient-specific models to aid diagnosis and therapy. The objective of this study is to validate the accuracy of patient coronary artery lumen area obtained from CT images based on intravascular ultrasound (IVUS). Methods and Results Morphometric data of 5 patient CT scans with 11 arteries from IVUS were reconstructed including the lumen cross sectional area (CSA), diameter and length. The volumetric data from CT images were analyzed at sub-pixel accuracy to obtain accurate vessel center lines and CSA. A new center line extraction approach was used where an initial estimated skeleton in discrete value was obtained using a traditional thinning algorithm. The CSA was determined directly without any circular shape assumptions to provide accurate reconstruction of stenosis. The root-mean-square error (RMSE) for CSA and diameter were 16.2% and 9.5% respectively. Conclusions The image segmentation and CSA extraction algorithm for reconstruction of coronary arteries proved to be accurate for determination of vessel lumen area. This approach provides fundamental morphometric data for patient-specific models to diagnose and treat coronary artery disease. PMID:24489811

Luo, Tong; Wischgoll, Thomas; Kwon Koo, Bon; Huo, Yunlong; Kassab, Ghassan S.

2014-01-01

269

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

270

Clinical and imaging predictors of intracerebral haemorrhage in stroke patients treated with intravenous tissue plasminogen activator  

PubMed Central

Objective: To evaluate clinical, biological, and pretreatment imaging variables for predictors of tissue plasminogen activator (tPA) related intracerebral haemorrhage (ICH) in stroke patients. Methods: 48 consecutive patients with hemispheric stroke were given intravenous tPA within seven hours of symptom onset, after computed tomography (CT) and magnetic resonance imaging (MRI) of the brain. Baseline diffusion weighted (DWI) and perfusion weighted (PWI) imaging volumes, time to peak, mean transit time, regional cerebral blood flow index, and regional cerebral blood volume were evaluated. The distribution of apparent diffusion coefficient (ADC) values was determined within each DWI lesion. Results: The symptomatic ICH rate was 8.3% (four of 48); the rate for any ICH was 43.8% (21 of 48). Univariate analysis showed that age, weight, history of hyperlipidaemia, baseline NIHSS score, glucose level, red blood cell count, and lacunar state on MRI were associated with ICH. However, mean 24 hour systolic blood pressure and a hyperdense artery sign on pretreatment CT were the only independent predictors of ICH. Patients with a hyperdense artery sign had larger pretreatment PWI and DWI lesion volumes and a higher NIHSS score. Analysis of the distribution of ADC values within DWI lesions showed that a greater percentage of pixels had lower ADCs (<400x10–6 mm2/s) in patients who experienced ICH than in those who did not. Conclusion: Key clinical and biological variables, pretreatment CT signs, and MRI indices are associated with tPA related intracerebral haemorrhage. PMID:15607998

Derex, L; Hermier, M; Adeleine, P; Pialat, J; Wiart, M; Berthezene, Y; Philippeau, F; Honnorat, J; Froment, J; Trouillas, P; Nighoghossian, N

2005-01-01

271

The Role of Magnetic Resonance Imaging in Management of Patients With Nonlobar Hypertensive Intracerebral Hemorrhage  

PubMed Central

Background and Purpose: Despite the increased use and availability of magnetic resonance imaging (MRI), its role in hypertensive intracerebral hemorrhage (ICH) remains uncertain. In this retrospective study, we assessed the utility of MRI in diagnosis and management of patients with hypertensive ICH. Methods: We retrospectively reviewed the charts of patients with ICH presenting to our hospital over an 18-month period. We included patients who presented with hypertensive ICH in typical locations and excluded lobar hemorrhages. We further isolated cases that had undergone MRI. Collected data included mean age, gender, location of hematoma, neuroradiologist’s interpretative report of the MRI, and management steps taken in response to the results of the MRI. Logistic regression was used to determine whether the overall yield of MRI in these patients was significant. Results: We found 222 patients with ICH in our database. Forty-eight patients met our inclusion criteria, of which 24 had brain MRI done as a part of their hospital workup. Brain MRI obtained in 2 (8%) of the 24 patients revealed abnormalities that led to a change in management. The diagnostic yield of MRI and the management decisions that followed were both insignificant. Conclusions: The diagnostic yield of brain MRI in patients with nonlobar hypertensive ICH is low and does not result in significant changes in management. PMID:25829985

Adeli, Amir

2015-01-01

272

Quantitative Ultrasound Spectroscopic Imaging for Characterization of Disease Extent in Prostate Cancer Patients1  

PubMed Central

Three-dimensional quantitative ultrasound spectroscopic imaging of prostate was investigated clinically for the noninvasive detection and extent characterization of disease in cancer patients and compared to whole-mount, whole-gland histopathology of radical prostatectomy specimens. Fifteen patients with prostate cancer underwent a volumetric transrectal ultrasound scan before radical prostatectomy. Conventional-frequency (~ 5 MHz) ultrasound images and radiofrequency data were collected from patients. Normalized power spectra were used as the basis of quantitative ultrasound spectroscopy. Specifically, color-coded parametric maps of 0-MHz intercept, midband fit, and spectral slope were computed and used to characterize prostate tissue in ultrasound images. Areas of cancer were identified in whole-mount histopathology specimens, and disease extent was correlated to that estimated from quantitative ultrasound parametric images. Midband fit and 0-MHz intercept parameters were found to be best associated with the presence of disease as located on histopathology whole-mount sections. Obtained results indicated a correlation between disease extent estimated noninvasively based on midband fit parametric images and that identified histopathologically on prostatectomy specimens, with an r2 value of 0.71 (P < .0001). The 0-MHz intercept parameter demonstrated a lower level of correlation with histopathology. Spectral slope parametric maps offered no discrimination of disease. Multiple regression analysis produced a hybrid disease characterization model (r2 = 0.764, P < .05), implying that the midband fit biomarker had the greatest correlation with the histopathologic extent of disease. This work demonstrates that quantitative ultrasound spectroscopic imaging can be used for detecting prostate cancer and characterizing disease extent noninvasively, with corresponding gross three-dimensional histopathologic correlation. PMID:25749174

Sadeghi-Naini, Ali; Sofroni, Ervis; Papanicolau, Naum; Falou, Omar; Sugar, Linda; Morton, Gerard; Yaffe, Martin J.; Nam, Robert; Sadeghian, Alireza; Kolios, Michael C.; Chung, Hans T.; Czarnota, Gregory J.

2015-01-01

273

Quantitative ultrasound spectroscopic imaging for characterization of disease extent in prostate cancer patients.  

PubMed

Three-dimensional quantitative ultrasound spectroscopic imaging of prostate was investigated clinically for the noninvasive detection and extent characterization of disease in cancer patients and compared to whole-mount, whole-gland histopathology of radical prostatectomy specimens. Fifteen patients with prostate cancer underwent a volumetric transrectal ultrasound scan before radical prostatectomy. Conventional-frequency (~5MHz) ultrasound images and radiofrequency data were collected from patients. Normalized power spectra were used as the basis of quantitative ultrasound spectroscopy. Specifically, color-coded parametric maps of 0-MHz intercept, midband fit, and spectral slope were computed and used to characterize prostate tissue in ultrasound images. Areas of cancer were identified in whole-mount histopathology specimens, and disease extent was correlated to that estimated from quantitative ultrasound parametric images. Midband fit and 0-MHz intercept parameters were found to be best associated with the presence of disease as located on histopathology whole-mount sections. Obtained results indicated a correlation between disease extent estimated noninvasively based on midband fit parametric images and that identified histopathologically on prostatectomy specimens, with an r(2) value of 0.71 (P<.0001). The 0-MHz intercept parameter demonstrated a lower level of correlation with histopathology. Spectral slope parametric maps offered no discrimination of disease. Multiple regression analysis produced a hybrid disease characterization model (r(2)=0.764, P<.05), implying that the midband fit biomarker had the greatest correlation with the histopathologic extent of disease. This work demonstrates that quantitative ultrasound spectroscopic imaging can be used for detecting prostate cancer and characterizing disease extent noninvasively, with corresponding gross three-dimensional histopathologic correlation. PMID:25749174

Sadeghi-Naini, Ali; Sofroni, Ervis; Papanicolau, Naum; Falou, Omar; Sugar, Linda; Morton, Gerard; Yaffe, Martin J; Nam, Robert; Sadeghian, Alireza; Kolios, Michael C; Chung, Hans T; Czarnota, Gregory J

2015-02-01

274

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

275

Using patient-specific phantoms to evaluate deformable image registration algorithms for adaptive radiation therapy.  

PubMed

The quality of adaptive treatment planning depends on the accuracy of its underlying deformable image registration (DIR). The purpose of this study is to evaluate the performance of two DIR algorithms, B-spline-based deformable multipass (DMP) and deformable demons (Demons), implemented in a commercial software package. Evaluations were conducted using both computational and physical deformable phantoms. Based on a finite element method (FEM), a total of 11 computational models were developed from a set of CT images acquired from four lung and one prostate cancer patients. FEM generated displacement vector fields (DVF) were used to construct the lung and prostate image phantoms. Based on a fast-Fourier transform technique, image noise power spectrum was incorporated into the prostate image phantoms to create simulated CBCT images. The FEM-DVF served as a gold standard for verification of the two registration algorithms performed on these phantoms. The registration algorithms were also evaluated at the homologous points quantified in the CT images of a physical lung phantom. The results indicated that the mean errors of the DMP algorithm were in the range of 1.0 ~ 3.1 mm for the computational phantoms and 1.9 mm for the physical lung phantom. For the computational prostate phantoms, the corresponding mean error was 1.0-1.9 mm in the prostate, 1.9-2.4mm in the rectum, and 1.8-2.1 mm over the entire patient body. Sinusoidal errors induced by B-spline interpolations were observed in all the displacement profiles of the DMP registrations. Regions of large displacements were observed to have more registration errors. Patient-specific FEM models have been developed to evaluate the DIR algorithms implemented in the commercial software package. It has been found that the accuracy of these algorithms is patient dependent and related to various factors including tissue deformation magnitudes and image intensity gradients across the regions of interest. This may suggest that DIR algorithms need to be verified for each registration instance when implementing adaptive radiation therapy. PMID:24257278

Stanley, Nick; Glide-Hurst, Carri; Kim, Jinkoo; Adams, Jeffrey; Li, Shunshan; Wen, Ning; Chetty, Indrin J; Zhong, Hualiang

2013-01-01

276

Using patient-specific phantoms to evaluate deformable image registration algorithms for adaptive radiation therapy  

PubMed Central

The quality of adaptive treatment planning depends on the accuracy of its underlying deformable image registration (DIR). The purpose of this study is to evaluate the performance of two DIR algorithms, B-spline–based deformable multipass (DMP) and deformable demons (Demons), implemented in a commercial software package. Evaluations were conducted using both computational and physical deformable phantoms. Based on a finite element method (FEM), a total of 11 computational models were developed from a set of CT images acquired from four lung and one prostate cancer patients. FEM generated displacement vector fields (DVF) were used to construct the lung and prostate image phantoms. Based on a fast-Fourier transform technique, image noise power spectrum was incorporated into the prostate image phantoms to create simulated CBCT images. The FEM-DVF served as a gold standard for verification of the two registration algorithms performed on these phantoms. The registration algorithms were also evaluated at the homologous points quantified in the CT images of a physical lung phantom. The results indicated that the mean errors of the DMP algorithm were in the range of 1.0 ~ 3.1 mm for the computational phantoms and 1.9 mm for the physical lung phantom. For the computational prostate phantoms, the corresponding mean error was 1.0–1.9 mm in the prostate, 1.9–2.4 mm in the rectum, and 1.8–2.1 mm over the entire patient body. Sinusoidal errors induced by B-spline interpolations were observed in all the displacement profiles of the DMP registrations. Regions of large displacements were observed to have more registration errors. Patient-specific FEM models have been developed to evaluate the DIR algorithms implemented in the commercial software package. It has been found that the accuracy of these algorithms is patient-dependent and related to various factors including tissue deformation magnitudes and image intensity gradients across the regions of interest. This may suggest that DIR algorithms need to be verified for each registration instance when implementing adaptive radiation therapy. PMID:24257278

Stanley, Nick; Glide-Hurst, Carri; Kim, Jinkoo; Adams, Jeffrey; Li, Shunshan; Wen, Ning; Chetty, Indrin J.; Zhong, Hualiang

2014-01-01

277

Myocardial perfusion imaging with thallium-201 to evaluate patients before and after percutaneous transluminal coronary angioplasty  

SciTech Connect

Thallium-201 imaging may be used to help determine the distribution and amount of myocardium in jeopardy and the success of revascularization after percutaneous transluminal coronary angioplasty. Single photon emission computed tomography is particularly advantageous because of its ability to differentiate vascular territories and thus evaluate patients with multivessel disease. Myocardial infarction resulting from complications such as distal embolization and side-branch occlusion can be detected. Thallium-201 imaging early after angioplasty may show abnormal results caused by transiently insufficient coronary flow reserve. However, studies performed 6 weeks or more after angioplasty accurately detect early restenosis and may identify those individuals likely to become symptomatic and eventually develop restenosis in the future.

DePuey, E.G. (St. Luke's-Roosevelt Hospital, Department of Nuclear Medicine, New York, NY (United States))

1991-09-01

278

Improving Soft-Tissue Contrast in Four-Dimensional Computed Tomography Images of Liver Cancer Patients Using a Deformable Image Registration Method  

SciTech Connect

Purpose: To investigate a deformable image registration method to improve soft-tissue contrast in four-dimensional (4D) computed tomography (CT) images of the liver. Methods and Materials: Ten patients with hepatocellular carcinoma underwent 4D CT scan for radiotherapy treatment planning on a positron emission tomography/CT scanner. Four-dimensional CT images were binned into 10 equispaced phases. The exhale phase served as the reference phase, and images from the other nine phases were coregistered to the reference phase image using an intensity-based, automatic deformable image registration method. Then the coregistered images were combined to create a single, high-quality reconstructed CT image at exhale phase as the new reference for target delineation. The extent of image quality enhancement was quantified relative to the original CT by calculating the signal-to-noise ratio and the contrast-to-noise ratio. Results: The soft tissue image contrast was noticeably better after deformable image registration than in the original scans. Signal-to-noise ratios inside the liver region of interest increased for all patients by a factor of 3.0 (range, 2.3-3.7). The improvement in image quality was not linearly proportionate to the number of images averaged. Using only 6 phases can achieve at least 85% of the contrast enhancement that can be achieved using all 10 phases. We also found that contrast enhancement was inversely proportional to the original image quality (p = 0.006), and the contrast enhancement is attained with little loss of spatial resolution. Conclusions: This deformable image registration method is feasible to improve soft-tissue image quality in 4D CT images.

Wang He [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Krishnan, Sunil [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Wang Xiaochun; Beddar, A. Sam; Briere, Tina M. [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Crane, Christopher H. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Mohan, Radhe [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Dong Lei [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)], E-mail: ldong@mdanderson.org

2008-09-01

279

Nuclear Medicine Imaging of Infection in Cancer Patients (With Emphasis on FDG-PET)  

PubMed Central

Infections are a common cause of death and an even more common cause of morbidity in cancer patients. Timely and adequate diagnosis of infection is very important. This article provides clinicians as well as nuclear medicine specialists with a concise summary of the most important and widely available nuclear medicine imaging techniques for infectious and inflammatory diseases in cancer patients with an emphasis on fluorodeoxyglucose positron emission tomography (FDG-PET). 67Ga-citrate has many unfavorable characteristics, and the development of newer radiopharmaceuticals has resulted in the replacement of 67Ga-citrate scintigraphy by scintigraphy with labeled leukocytes or FDG-PET for the majority of conditions. The sensitivity of labeled leukocyte scintigraphy in non-neutropenic cancer patients is comparable with that in patients without malignancy. The specificity, however, is lower because of the uptake of labeled leukocytes in many primary tumors and metastases, most probably as a result of their inflammatory component. In addition, labeled leukocyte scintigraphy cannot be used for febrile neutropenia because of the inability to harvest sufficient peripheral leukocytes for in vitro labeling. FDG-PET has several advantages over these conventional scintigraphic techniques. FDG-PET has shown its usefulness in diagnosing septic thrombophlebitis in cancer patients. It has also been shown that imaging of infectious processes using FDG-PET is possible in patients with severe neutropenia. Although larger prospective studies examining the value of FDG-PET in cancer patients suspected of infection, especially in those with febrile neutropenia, are needed, FDG-PET appears to be the most promising scintigraphic technique for the diagnosis of infection in this patient group. PMID:21680576

Vos, Fidel J.; van der Graaf, Winette T.A.; Oyen, Wim J.G.

2011-01-01

280

Impact of thallium-201 imaging on clinical assessment and management of patients with chest pain  

SciTech Connect

The histories, rest, and exercise ECG results of 60 patients without myocardial infarction complaining of chest pain were submitted to 6 physicians (3 cardiologists and 3 noncardiologists) who were unaware of the angiographic findings. The physicians were requested to estimate the probability of coronary artery disease present in percentages and to assess the need for coronary angiography on a five-point scale (1 . definitely not indicated, 5 . definitely indicated). After obtaining the results of thallium-201 imaging following dipyridamole (0.50 mg/kg intravenously) administration, the physicians were again requested to estimate probability and need for angiography. In the 43 patients with coronary artery disease the judgment of probability was increased significantly after /sup 201/Tl from 75.6 +/- 20.2% to 82.9 +/- 23.2% (p less than 0.001) and the need for angiography from 4.3 +/- 0.9% to 4.5 +/- 0.9% (p less than 0.001). In the subgroup of patients with atypical angina the relative change in probability was higher than in other subgroups of patients with coronary artery disease. In the 17 patients with normal coronary arteries the probability estimation fell after /sup 201/Tl from 36.7 +/- 22.0% to 24.8 +/- 21.0% (p less than 0.001), the need for angiography was decreased from 2.7 +/- 1.1% to 2.2 +/- 1.2% (p less than 0.001). With the /sup 201/Tl information, cardiologists performed a better diagnostic differentiation of patients with and without coronary artery disease than noncardiologists. The study demonstrates the improvement of clinical diagnosis in patients with chest pain by thallium-201 imaging and confirms the favorable influence of the method on the management of the patients in terms of indications for coronary angiography.

Schmoliner, R.; Dudczak, R.; Kronik, G.; Moesslacher, H.; Zangeneh, M.; Pollak, C.; Schurz, B.; Schoberwalter, A.

1984-12-01

281

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

282

[Imaging of cancer of the uterine cervix].  

PubMed

Imaging of uterine cervix carcinoma has evolved during the last decade. Recent developments in magnetic resonance imaging have expanded the role of MRI in evaluating the pathology of uterine cervix carcinoma. MRI is now the modality of choice for tumor staging, evaluating tumor response to treatment, diagnosing recurrences and for evaluating pregnant patients. MRI images will soon be used to calculate dosimetry for brachytherapy with matching and fusion software. PMID:10812355

Viala, J

2000-01-01

283

Tc-99m-diethyl-IDA imaging: clinical evaluation in jaundiced patients  

SciTech Connect

Hepatobiliary imaging with Tc-99m-N,..cap alpha..-(2,6-diethylacetanilide)-iminodiacetic acid (Tc-diethyl-IDA) was performed in 91 jaundiced patients with documented hepatobiliary damage and serum total bilirubin up to 35 mg/dl. There were 56 patients with obstructive jaundice and 35 with hepatocellular disease. Correct discrimination between hepatocellular and obstructive jaundice was possible with an overall accuracy of 90%. Agreement with the final clinical diagnosis was obtained in 97% of patients with hepatocellular disease, and in 86% of patients with obstructive jaundice. The reliability of the test was inversely related to the serum bilirubin levels below 10 mg/dl to 83% for bilirubin between 10 and 20 mg/dl. Above 20 mg/dl, the demonstration of a mechanical obstruction was possible in only one out of the four patients with obstructive jaundice. The high predictive values of the test illustrate that Tc-diethyl-IDA imaging constitutes a reliable method to demonstrate an obstructive cause for the jaundice as long as the bilirubin level remains below 20 mg/dl.

Pauwels, S.; Piret, L.; Schoutens, A.; Vandermoten, G.; Beckers, C.

1980-11-01

284

Simultaneous liver iron and fat measures by magnetic resonance imaging in patients with hyperferritinemia.  

PubMed

Abstract Objective. Hyperferritinemia is frequent in chronic liver diseases of any cause, but the extent to which ferritin truly reflects iron stores is variable. In these patients, both liver iron and fat are found in variable amount and association. Liver biopsy is often required to quantify liver fat and iron, but sampling variability and invasiveness limit its use. We aimed to assess single breath-hold multiecho magnetic resonance imaging (MRI) for the simultaneous lipid and iron quantification in patients with hyperferritinemia. Material and methods. We compared MRI results for both iron and fat with their respective gold standards - liver iron concentration and computer-assisted image analysis for steatosis on biopsy. We prospectively studied 67 patients with hyperferritinemia and other 10 consecutive patients were used for validation. We estimated two linear calibration equations for the prediction of iron and fat based on MRI. The agreement between MRI and biopsy was evaluated. Results. MRI showed good performances in both the training and validation samples. MRI information was almost completely in line with that obtained from liver biopsy. Conclusion. Single breath-hold multiecho MRI is an accurate method to obtain a valuable measure of both liver iron and steatosis in patients with hyperferritinemia. PMID:25633726

Galimberti, Stefania; Trombini, Paola; Bernasconi, Davide Paolo; Redaelli, Irene; Pelucchi, Sara; Bovo, Giorgio; Di Gennaro, Filiberto; Zucchini, Nicola; Paruccini, Nicoletta; Piperno, Alberto

2015-04-01

285

Hemodynamic analysis of patients in intensive care unit based on diffuse optical spectroscopic imaging system  

NASA Astrophysics Data System (ADS)

Diffuse optical spectroscopic imaging (DOSI) is a technique to assess the spatial variation in absorption and scattering properties of the biological tissues and provides the monitoring of changes in concentrations of oxy-hemoglobin and deoxy-hemoglobin. In our preliminary study, the temporal tracings of hemodynamic oxygenation are measured with DOSI and venous occlusion test (VOT) from normal subjects, patients with heart failure and patients with sepsis in intensive care unit (ICU). In experiments, the obvious differences of hemodynamic signals can be observed among the three groups. The physiological relevance of VOT hemodynamics with respect to diseases is also discussed in this paper.

Hsieh, Yao-Sheng; Wang, Chun-Yang; Ling, Yo-Wei; Chuang, Ming-Lung; Chuang, Ching-Cheng; Tsai, Jui-che; Lu, Chih-Wei; Sun, Chia-Wei

2010-02-01

286

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

287

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

288

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

289

MR imaging and cognitive correlates of relapsing-remitting multiple sclerosis patients with cerebellar symptoms.  

PubMed

Multiple sclerosis (MS) is a demyelinating disease affecting the central nervous system, frequently associated with cognitive impairments. Damages of the cerebellum are very common features of patients with MS, although the impact of this clinical factor is generally neglected. Recent evidence from our group demonstrated that MS patients with cerebellar damages are characterized by selective cognitive dysfunctions related to attention and language abilities. Here, we aimed at investigating the presence of neuroanatomical abnormalities in relapsing-remitting MS patients with (RR-MSc) and without (RR-MSnc) cerebellar signs. Twelve RR-MSc patients, 14 demographically, clinically, and radiologically, matched RR-MSnc patients and 20 controls were investigated. All patients underwent neuropsychological assessment. After refilling of FLAIR lesions on the 3D T1-weighted images, VBM was performed using SPM8 and DARTEL. A correlation analysis was performed between VBM results and neuropsychological variables characterizing RR-MSc patients. Despite a similar clinical status, RR-MSc patients were characterized by more severe cognitive damages in attention and language domains with respect to RR-MSnc and controls. With respect to controls, RR-MSnc patients were characterized by a specific atrophy of the bilateral thalami that became more widespread (including motor cortex) in the RR-MSc group (FWE < 0.05). However, consistent with their well-defined neuropsychological deficits, RR-MSc group showed atrophies in the prefrontal and temporal cortical areas when directly compared with RR-MSnc group. Our results demonstrated that RR-MS patients having cerebellar signs were characterized by a distinct neuroanatomical profile, mainly involving cortical regions underpinning executive functions and verbal fluency. PMID:23271221

Cerasa, Antonio; Valentino, Paola; Chiriaco, Carmelina; Pirritano, Domenico; Nisticò, Rita; Gioia, Cecilia M; Trotta, Maria; Del Giudice, Francesco; Tallarico, Tiziana; Rocca, Federico; Augimeri, Antonio; Bilotti, Giacinta; Quattrone, Aldo

2013-05-01

290

Positron Emission Tomography Imaging of Risperidone Augmentation in Serotonin Reuptake Inhibitor-Refractory Patients  

Microsoft Academic Search

We studied 15 nondepressed patients with obsessive-compulsive disorder (OCD) who were nonresponders to serotonin reuptake inhibitors with an additive trial of risperidone. Positron emission tomography with 18F-deoxyglucose and magnetic resonance imaging was obtained at baseline and following 8 weeks of either risperidone or placebo in a double-blind parallel group design. Risperidone treatment was associated with significant increases in relative metabolic

Monte S. Buchsbaum; Eric Hollander; Stefano Pallanti; Nicolò Baldini Rossi; Jimcy Platholi; Randall Newmark; Rachel Bloom; Erica Sood

2006-01-01

291

An Expanding Trapezium Cluster?  

E-print Network

Simulations with Aarseth's (1994) NBODY5 code are presented of an initially dense binary-rich cluster. It is assumed that the star formation efficiency is 50 per cent with instantaneous mass loss. The model central density and velocity dispersion agree with the observational constraints if expansion is only about 6x10^4 yr old. Additionally, the observed binary proportion constrains the primordial proportion to have been significantly less than in Taurus--Auriga. The claim that a variation of the birth binary proportion with gas cloud parameters has been detected, however, can only be verified if the cluster can be shown to be expanding rapidly.

Kroupa, P

1998-01-01

292

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

293

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

294

High Total Hospitalization Cost but Low Cost of Imaging Studies in Recurrent Acute Ischemic Stroke Patients  

PubMed Central

Background Due to the high risk and severity of recurrence after stroke attack, recurrence is a major reason contributing to the disease burden. This study aims to determine whether recurrence is a significant contributor of hospitalization cost in items for ischemic stroke patients. Methods This study assessed acute ischemic stroke patients admitted to an academic medical center in 2003 through 2009. The t-test and Chi-square tests were used to compare first-ever and recurrent ischemic stroke groups in terms of total and categorized hospitalization cost, and multiple regression was performed to assess the influence of stroke recurrence. Results Recurrent ischemic strokes were associated with higher total cost, but examination cost showed no difference between the two groups. The recurrent stroke group showed higher laboratory but lower imaging cost. Of imaging studies, there was no significant difference in computed tomography scan cost while the first-ever stroke group spent more on magnetic resonance imaging and sonography. Controlling for other influential factors, recurrence was discovered to be a significant factor in lowering examination cost. Conclusions The findings of stroke recurrence in lowering examination cost could be explained from two perspectives, different clinical patterns of healthcare utilization and patients' economic status in recurrent stroke. PMID:25047140

Kwon, Young Dae; Yoon, Sung Sang; Chang, Hyejung

2014-01-01

295

Application of image analysis in the myocardial biopsies of patients with dilated cardiomyopathy  

NASA Astrophysics Data System (ADS)

The aim of our study is to investigate if myocardial fibrosis measured by image analysis may be considered as an important and accurate index of dilated cardiomyopathy and its prognosis. The study group consisted of 24 patients with dilated cardiomyopathy which was diagnosed by echocardiography, radionuclide ventriculography, cardiac catheterization and left ventricular endomyocardial biopsy. The patients' overall disability was conventionally expressed with the criteria for functional capacity. Using image analysis the percentage of fibrosis in a total of 35 myocardial biopsies was measured accurately. A comparison study between the percentage of myocardial fibrosis and the clinical parameters (left ventricular ejection fraction and overall functional capacity) showing the degree of each patient's heart failure followed. A correlation was found among fibrosis, left ventricular ejection fraction and overall functional capacity. The cases with small values of fibrosis (less than 10%) have big values of ejection fraction and belong in Class I of overall functional capacity. The cases with big values of fibrosis (greater than 10%) belong in Classes III and IV of overall functional capacity and have small values of ejection fraction. The results of the comparison study were presented graphically and were considered significant. Myocardial fibrosis measured by image analysis might be considered an important prognostic index of dilated cardiomyopathy.

Agapitos, Emanuel; Kavantzas, Nikolaos; Bakouris, M. G.; Kassis, Kyriakos A.; Nanas, J.; Margari, Z.; Davaris, P.

1996-04-01

296

Hybrid SPECT/CT Imaging in the Evaluation of Coronary Stenosis: Role in Diabetic Patients  

PubMed Central

Purpose. Our purpose was to combine the results of the MDCT (multidetector computed tomography) morphological data and the SPECT (single-photon emission computed tomography) data using hybrid imaging to overcome the limits of the MDCT in the evaluation of coronary stenosis in diabetic patients with large amount of calcium in the coronary arteries. Method and Materials. 120 diabetic patients underwent MDCT examination and SPECT examination. We evaluated 324 coronary arteries. After the examinations, we merged CT and SPECT images. Results. CT evaluation: 52 (32.8%) coronaries with stenosis ? 50%, 228 (70.4%) with stenosis < 50%, and 44 (13.6%) with a doubtful evaluation. SPECT evaluation: 80 (24.7%) areas with hypoperfusion, 232 (71.6%) with normal perfusion, and 12 (3.7%) with a doubtful evaluation. Of 324 coronary arteries and corresponding areas, the hybrid SPECT/CT evaluation showed 92 (28.4%) areas with hypoperfusion, and 232 (71.6%) with normal perfusion. Conclusion. Hybrid CT/SPECT imaging could be useful in the detection of significant coronary stenosis in patients with large amount of coronary calcifications. PMID:24959556

Romagnoli, Andrea; Schillaci, Orazio; Arganini, Chiara; Gaspari, Eleonora; Ricci, Aurora; Morosetti, Daniele; Coco, Irene; Crusco, Sonia; Calabria, Ferdinando; Sperandio, Massimiliano; Simonetti, Giovanni

2013-01-01

297

[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

298

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

299

Optomap ultrawide field imaging identifies additional retinal abnormalities in patients with diabetic retinopathy  

PubMed Central

Purpose To compare diabetic retinopathy (DR) severity grading between Optomap ultrawide field scanning laser ophthalmoscope (UWFSLO) 200° images and an Early Treatment Diabetic Retinopathy Study (ETDRS) seven-standard field view. Methods Optomap UWFSLO images (total: 266) were retrospectively selected for evidence of DR from a database of eye clinic attendees. The Optomap UWFSLO images were graded for DR severity by two masked assessors. An ETDRS seven-field mask was overlaid on the Optomap UWFSLO images, and the DR grade was assessed for the region inside the mask. Any interassessor discrepancies were adjudicated by a senior retinal specialist. Kappa agreement levels were used for statistical analysis. Results Fifty images (19%) (P<0.001) were assigned a higher DR level in the Optomap UWFSLO view compared to the ETDRS seven-field view, which resulted in 40 images (15%) (P<0.001) receiving a higher DR severity grade. DR severity grades in the ETDRS seven-field view compared with the Optomap UWFSLO view were identical in 85% (226) of the images and within one severity level in 100% (266) of the images. Agreement between the two views was substantial: unweighted ? was 0.74±0.04 (95% confidence interval: 0.67–0.81) and weighted ? was 0.80±0.03 (95% confidence interval: 0.74–0.86). Conclusion Compared to the ETDRS seven-field view, a significant minority of patients are diagnosed with more severe DR when using the Optomap UWFSLO view. The clinical significance of additional peripheral lesions requires evaluation in future prospective studies using large cohorts. PMID:25848202

Price, Liam D; Au, Stephanie; Chong, N Victor

2015-01-01

300

Robust spectral analysis of videocapsule images acquired from celiac disease patients  

PubMed Central

Background Dominant frequency (DF) analysis of videocapsule endoscopy images is a new method to detect small intestinal periodicities that may result from mechanical rhythms such as peristalsis. Longer periodicity is related to greater image texture at areas of villous atrophy in celiac disease. However, extraneous features and spatiotemporal phase shift may mask DF rhythms. Method The robustness of Fourier and ensemble averaging spectral analysis to compute DF was tested. Videocapsule images from the distal duodenum of 11 celiac patients (frame rate 2/s and pixel resolution 576 × 576) were analyzed. For patients 1, 2, ... 11, respectively, a total of 10, 11, ..., 20 sequential images were extracted from a randomly selected time epoch. Each image sequence was artificially repeated to 200 frames, simulating periodicities of 0.2, 0.18, ..., 0.1Hz, respectively. Random white noise at four different levels, spatiotemporal phase shift, and frames with air bubbles were added. Power spectra were constructed pixel-wise over 200 frames, and an average spectrum was computed from the 576 × 576 individual spectra. The largest spectral peak in the average spectrum was the estimated DF. Error was defined as the absolute difference between actual DF and estimated DF. Results For Fourier analysis, the mean absolute error between estimated and actual DF was 0.032 ± 0.052Hz. Error increased with greater degree of random noise imposed. In contrast, all ensemble average estimates precisely predicted the simulated DF. Conclusions The ensemble average DF estimate of videocapsule images with simulated periodicity is robust to noise and spatiotemporal phase shift as compared with Fourier analysis. Accurate estimation of DF eliminates the need to impose complex masking, extraction, and/or corrective preprocessing measures. PMID:21906318

2011-01-01

301

Neurological adverse events in patients receiving anti-TNF therapy: a prospective imaging and electrophysiological study  

PubMed Central

Introduction The aim was to investigate the frequency of neurological adverse events in patients with rheumatoid arthritis (RA) and spondylarthropathies (SpA) treated with tumor necrosis factor (TNF) ? antagonists. Methods Seventy-seven patients eligible for anti-TNF? therapy were evaluated. There were 36 patients with RA, 41 with SpA [24 psoriatic arthritis (PsA) and 17 with ankylosing spondylitis (AS)]. All patients had a complete physical and neurological examination. Brain and cervical spine magnetic resonance imaging (MRI) and neurophysiological tests were performed in all patients before the initiation of anti-TNF? therapy and after a mean of 18 months or when clinical symptoms and signs indicated a neurological disease. Exclusion criteria included hypertension, diabetes mellitus, dyslipidemia, heart arrhythmias, atherothrombotic events, vitamin B12 and iron deficiency, head and neck trauma and neurological surgeries. Results Two patients did not receive anti-TNF? therapy because brain MRIs at baseline revealed lesions compatible with demyelinating diseases. Thus, 75 patients received anti-TNF? (38 infliximab, 19 adalimumab and 18 etanercept). Three patients developed neurological adverse events. A 35-year-old man with PsA after 8 months of infliximab therapy presented with paresis of the left facial nerve and brain MRI showed demyelinating lesions. Infliximab was discontinued and he was treated with pulses of corticosteroids recovering completely after two months. The second patient was a 45-year-old woman with RA who after 6 months of adalimumab therapy presented with optic neuritis. The third patient was a 50-year-old woman with AS, whom after 25 months of infliximab therapy, presented with tingling and numbness of the lower extremities and neurophysiological tests revealed peripheral neuropathy. In both patients anti-TNF were discontinued and they improved without treatment after 2 months. The rest of our patients showed no symptoms and MRIs showed no abnormalities. The estimated rate of neurological adverse events in patients treated with anti-TNF therapy is 4% (3/75). Conclusions Neurological adverse events after anti-TNF? therapy were observed in our patient. Brain MRI and neurophysiological tests are essential tools to discriminate neurological diseases. PMID:24938855

2014-01-01

302

Morphological and functional imaging in neurological and non-neurological Wilson's patients.  

PubMed

Wilson's disease causes disturbances of the central nervous system, affecting it both directly through copper toxicity and indirectly subject to a copper-induced hepatopathy, resulting in morphological and physiological changes in brain structures that can be captured by means of magnetic resonance imaging (MRI), (123)I-?-CIT (2?-carbomethoxy-3? (4-iodophenyl)tropane)-SPECT (single photon emission computed tomography), (123)I-IBZM (benzamide)-SPECT and [(18)F]FDG -PET (fluorodeoxyglucose-positron emission tomography). MRI can reveal even slight morphological changes in non-neurological Wilson's patients. More marked findings in neurological Wilson's patients become evident in T1- and T2-weighted MRI. T1-weighted MRI predominantly detects atrophic changes, whereas T2-weighted MRI regularly records signal changes in the putamen. With the aid of these three nuclear-medicine examinations, nigrostriatal and metabolic disturbances are identified in neurological Wilson's patients only. Sufficient decoppering therapy prevents progression and even tends to improve symptoms. A correlation between any of the imaging findings in patients with the genetic phenotype and the incidence of the most common mutation H1069Q (homozygote or compound heterozygote) or other mutations could not be substantiated. PMID:24495036

Hermann, Wieland

2014-05-01

303

Patient experiences and preferences: development of practice guidelines in a cancer imaging department  

PubMed Central

Abstract Objective: To improve patient management based on analysis of the results of a survey conducted during their visit to the imaging department of a cancer centre. Materials and methods: A questionnaire comprising 30 single-response questions on a dichotomous scale or a 3- or 4-modality scale was developed by three radiologists specialized in oncology, the head of our quality assurance department, a psycho-oncologist, a psycho-sociologist, a biostatistician and a member of our institute's Patient Committee. Questions concerned reception, information provided about the examinations, examination experiences, the relational qualities and availability of health care professionals, the interview with the radiologist and announcement of the examination results. Results: The questionnaire was given to 190 patients in the waiting room before a standard radiography or ultrasound examination (33%), mammography and breast ultrasound (33%), computed tomography (CT) or magnetic resonance imaging (MRI) (34%). The return rate was 81%. This article analyses the responses to the various questions in terms of either percentages or detailed replies and suggestions. Conclusion: Analysis of the patients’ experience and their suggestions provided objective elements concerning their real wishes in relation to each step of their management and identified changes and improvements to be made to the organization and daily functioning of the department. PMID:19965300

Apiou, F.; Leclère, J.; Sévellec, M.; Asselain, B.; Brédart, A.; Neuenschwander, S.

2009-01-01

304

Cardiac MR imaging in constrictive pericarditis: multiparametric assessment in patients with surgically proven constriction.  

PubMed

To assess the utility of cardiac magnetic resonance (MR) imaging in the diagnosis of constrictive pericarditis (CP). This study was approved by the institutional review board, with a waiver of informed consent. A total of 42 consecutive patients (mean age, 55 ± 16 years; 3 women, 39 men) with CP treated with pericardiectomy who had undergone cardiac MR before surgery were evaluated retrospectively. An additional 21 patients were evaluated as a control group; of these, 10 consecutive patients received cardiac MR for reasons other than suspected pericardial disease, and 11 consecutive patients had a history of pericarditis but no clinical suspicion of pericardial constriction. MR imaging parameters were analyzed independently and with a decision tree algorithm for usefulness in the prediction of CP. Catheterization data were also reviewed when available. A model combining pericardial thickness and relative interventricular septal (IVS) excursion provided the best overall performance in prediction of CP (C statistic, 0.98, 100 % sensitivity, 90 % specificity). Several individual parameters also showed strong predictive value in the assessment of constriction, including relative IVS excursion (sensitivity, 93 %; specificity, 95 %), pericardial thickness (sensitivity, 83 %; specificity, 100 %), qualitative assessment of pathologic coupling (sensitivity, 88 %; specificity, 100 %), diastolic IVS bounce (sensitivity, 90 %; specificity, 85 %), left ventricle area change (sensitivity, 86 %; specificity, 100 %), and eccentricity index (sensitivity, 86 %; specificity, 90 %; all P < 0.001). Strong agreement was observed between catheterization and surgical findings of constriction (97 %). Cardiac MR provides robust quantitative and qualitative analysis for the diagnosis of CP. PMID:25672267

Bolen, Michael A; Rajiah, Prabhakar; Kusunose, Kenya; Collier, Patrick; Klein, Allan; Popovi?, Zoran B; Flamm, Scott D

2015-04-01

305

Prognostic value of exercise thallium-201 imaging in patients presenting for evaluation of chest pain  

SciTech Connect

Accurate prognostic information is important in determining optimal management of patients presenting for evaluation of chest pain. In this study, the ability of exercise thallium-201 myocardial imaging to predict future cardiac events (cardiovascular death or nonfatal myocardial infarction) was correlated with clinical, coronary and left ventricular angiographic and exercise electrocardiographic data in 139 consecutive, nonsurgically managed patients followed-up over a 3 to 5 year period (mean follow-up, 3.7 +/- 0.9), using a logistic regression analysis. Among patients without prior myocardial infarction (100 of 139), the number of myocardial segments with transient thallium-201 defects was the only statistically significant predictor of future cardiac events when all patient variables were evaluated. Among patients with myocardial infarction before evaluation (39 of 139), angiographic ejection fraction was the only significant predictor of future cardiac events when all variables were considered. This study suggests an approach to evaluate the risk of future cardiac events in patients with possible ischemic heart disease.

Brown, K.A.; Boucher, C.A.; Okada, R.D.; Guiney, T.E.; Newell, J.B.; Strauss, H.W.; Pohost, G.M.

1983-04-01

306

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

307

Quality of life for our patients: how media images and messages: influence their perceptions.  

PubMed

Media messages and images shape patients' perceptions about quality of life (QOL) through various "old" media-literature, film, television, and music-and so-called "new" media-the Internet, e-mail, blogs, and cell phones. In this article, the author provides a brief overview of QOL from the academic perspectives of nursing, psychology, behavioral medicine, multicultural studies, and consumer marketing. Selected theories about mass communication are discussed, as well as new technologies and their impact on QOL in our society. Examples of media messages about QOL and the QOL experience reported by patients with cancer include an excerpt from the Canadian Broadcasting Corporation radio interview with author Carol Shields, the 60 Minutes television interview focusing on Elizabeth Edwards (wife of presidential candidate John Edwards), and an excerpt from the 1994 filmThe Shawshank Redemption. Nurses are challenged to think about how they and their patients develop their perceptions about QOL through the media. PMID:18258574

Carr, Ellen R

2008-02-01

308

Vector Analysis of Prostate Patient Setup With Image-Guided Radiation Therapy via kV Cone Beam Computed Tomography  

SciTech Connect

Purpose: To analyze the daily setup variations in a cohort of intensity-modulated radiation therapy (IMRT) prostate cancer patients who had received daily image-guided RT without the use of fiducial markers to determine if daily image guidance is necessary. Methods and Materials: 2134 Kilovoltage (kV) cone beam computed tomography (CBCT) images were analyzed, with three shifts recorded for each image. The number of times that the vector of the combined shifts would have exceeded the planning tumor volume (PTV) margin was tallied. Then, the average scalar shift of the first five images was removed from all subsequent images for a given patient, and the number of days for which the shift vector was greater than the three-dimensional clinical tumor volume-PTV (3D CTV-PTV) margin (8 mm, created with rolling ball technique) was recorded. Additionally, the scalar shifts from every other fraction were studied to determine if the individual patient's shift vector would be adequately sampled if CBCT was not performed daily, thus reducing patient imaging dose without compromising treatment quality. Results: There were 297 cases where the vector shift was initially greater than the PTV margin. By correcting each patient's data set by the average shift of their first five images the total was 248 cases. By considering only every other image of each patient data set (after correction for the first 5 days), only 137 days in which the CTV was outside the PTV would have been seen. Conclusions: Daily imaging is recommended for prostate cancer IMRT patients in order to know the 3D (vector) position of the CTV and to ensure that it is always within the PTV margin. Correcting the data set by the average shift from the first 5 days reduces the overall number of outlier days but does not eliminate them completely.

Perks, Julian, E-mail: julian.perks@ucdmc.ucdavis.ed [Department of Radiation Oncology, University of California, Davis, Sacramento, California (United States); Turnbull, Helen; Liu Tianxiao; Purdy, James; Valicenti, Richard [Department of Radiation Oncology, University of California, Davis, Sacramento, California (United States)

2011-03-01

309

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

310

Expanded Clinical Spectrum of Enhanced S-Cone Syndrome  

PubMed Central

IMPORTANCE New funduscopic findings in patients with enhanced S-cone syndrome (ESCS) may help clinicians in diagnosing this rare autosomal recessive retinal dystrophy. OBJECTIVE To expand the clinical spectrum of ESCS due to mutations in the NR2E3 gene. DESIGN Retrospective, noncomparative case series of 31 patients examined between 1983 and 2012. SETTING Academic and private ophthalmology practices specialized in retinal dystrophies. PARTICIPANTS A cohort of patients diagnosed with ESCS and harboring known NR2E3 mutations. INTERVENTION Patients had ophthalmic examinations including visual function testing that led to the original diagnosis. MAIN OUTCOMES AND MEASURES New fundus features captured with imaging modalities. RESULTS New clinical observations in ESCS include (1) torpedo-like, deep atrophic lesions with a small hyperpigmented rim, variably sized and predominantly located along the arcades; (2) circumferential fibrotic scars in the posterior pole with a spared center and large fibrotic scars around the optic nerve head; and (3) yellow dots in areas of relatively normal-appearing retina. CONCLUSIONS AND RELEVANCE Enhanced S-cone syndrome has more pleiotropy than previously appreciated. While the nummular type of pigmentation at the level of the retinal pigment epithelium and cystoid or schisis-like maculopathy with typical functional findings remain classic hallmarks of the disease, changes such as circumferential fibrosis of the macula or peripapillary area and “torpedo-like” lesions along the vascular arcades may also direct the clinical diagnosis and focus on screening the NR2E3 gene for a molecular diagnosis. PMID:23989059

Yzer, Suzanne; Barbazetto, Irene; Allikmets, Rando; van Schooneveld, Mary J.; Bergen, Arthur; Tsang, Stephen H.; Jacobson, Samuel G.; Yannuzzi, Lawrence A.

2015-01-01

311

Attitudinal and perceptual factors in body image distortion: an exploratory study in patients with anorexia nervosa  

PubMed Central

Background Body image disturbance is a core feature of anorexia nervosa (AN). Attitudinal and cognitive biases as well as fundamental perceptual differences have been hypothesized to play a role in this disturbance. Method This study investigated body image dissatisfaction and distortion, haptic perception and perfectionism in 30 patients with AN and 31 age-matched healthy controls. Participants completed perceptual tasks and self-report measures. Results As predicted, participants with AN scored significantly higher on body dissatisfaction, perfectionism measures and had greater body distortion (as assessed by a body size estimation task). Cognitive–affective factors and perfectionism were highly correlated with body image distortion in AN. No significant differences were found between groups on the generic perception task. Conclusions Findings did not confirm the hypothesis of fundamental perceptual inefficiencies in body image disturbance in individuals with AN. Despite renewed interest in fundamental perceptual factors implicated in body image disturbance, these findings suggest that it continues to be important to focus treatment on cognitive affective biases versus fundamental perceptual inefficiencies. PMID:24999398

2013-01-01

312

Expanding Patient Options: Minilaparotomy for Hysterectomy  

MedlinePLUS

... recovery, it’s very comparable. Again, one approach is never something that you should always use for every hysterectomy. Last week ... finally, I’d like to end by leaving you with a story that I recently heard. There was a concept ... they took the best of everything. I like to talk about the company like ...

313

Transplantation of ex vivo expanded cord blood.  

PubMed

Umbilical cord blood (CB) from unrelated donors is increasingly used to restore hematopoiesis after myeloablative therapy. CB transplants are associated with higher rates of delayed and failed engraftment than are bone marrow transplants, particularly for adult patients. We studied the ex vivo expansion of CB in an attempt to improve time to engraftment and reduce the graft failure rate in the recipients. In this feasibility study, 37 patients (25 adults, 12 children) with hematologic malignancies (n = 34) or breast cancer (n = 3) received high-dose therapy followed by unrelated allogeneic CB transplantation. A fraction of each patient's CB allograft was CD34-selected and cultured ex vivo for 10 days prior to transplantation in defined media with stem cell factor, granulocyte colony-stimulating factor, and megakaryocyte growth and differentiation factor. The remainder of the CB graft was infused without further manipulation. Two sequential cohorts of patients were accrued to the study. The first cohort had 40% and the second cohort had 60% of their CB graft expanded. Patients received a median of 0.99 x 10(7) total nucleated cells (expanded plus unexpanded) per kilogram. The median time to engraftment of neutrophils was 28 days (range, 15-49 days) and of platelets was 106 days (range, 38-345 days). All evaluable patients who were followed for 28 days or longer achieved engraftment of neutrophils. Grade III/IV acute GVHD was documented in 40% and extensive chronic GVHD in 63% of patients. At a median follow-up of 30 months, 13 (35%) of 37 of patients survived. This study demonstrates that the CD34 selection and ex vivo expansion of CB prior to transplantation of CB is feasible. Additional accrual will be required to assess the clinical efficacy of expanded CB progenitors. PMID:12171483

Shpall, Elizabeth J; Quinones, Ralph; Giller, Roger; Zeng, Chan; Baron, Anna E; Jones, Roy B; Bearman, Scott I; Nieto, Yago; Freed, Brian; Madinger, Nancy; Hogan, Christopher J; Slat-Vasquez, Vicki; Russell, Peggy; Blunk, Betsy; Schissel, Deborah; Hild, Elaine; Malcolm, Janet; Ward, William; McNiece, Ian K

2002-01-01

314

Optical imaging of progenitor cell homing to patient-derived tumors.  

PubMed

Capitalizing on cellular homing to cancer is a promising strategy for targeting malignant cells for diagnostic, monitoring and therapeutic purposes. Murine C17.2 neural progenitor cells (NPC) demonstrate a tropism for cell line-derived tumors, but their affinity for patient-derived tumors is unknown. We tested the hypothesis that NPC accumulate in patient-derived tumors at levels detectable by optical imaging. Mice bearing solid tumors after transplantation with patient-derived leukemia cells and untransplanted controls received 10(6) fluorescent DiR-labeled NPC daily for 1-4 days, were imaged, then sacrificed. Tissues were analyzed by immunofluorescence and flow cytometry to detect tumor cell engraftment (CD45) and NPC (FITC-? galactosidase or DiR). Tumors consisted primarily of CD45-positive cells and demonstrated mild fluorescence, corresponding to frequent clusters of FITC-? gal-positive cells. Both transplanted and control mice demonstrated the highest fluorescent signal in the spleens and other tissues of the reticuloendothelial activating system. However, only rare FITC-? gal-positive cells were detected in the mildly engrafted transplanted spleens and none in the control spleens, suggesting that their high DiR signal reflects the sequestration of DiR-positive debris. The mildly engrafted transplanted kidneys demonstrated low fluorescent signal and rare FITC-? gal-positive cells whereas control kidneys were negative. Results indicate that NPC accumulate in tissues containing patient-derived tumor cells in a manner that is detectable by ex vivo optical imaging and proportional to the level of tumor engraftment, suggesting a capacity to home to micrometastatic disease. As such, NPC could have significant clinical applications for the targeted diagnosis and treatment of cancer. PMID:22991319

Newton, Isabel G; Plaisted, Warren C; Messina-Graham, Steven; Abrahamsson Schairer, Annelie E; Shih, Alice Y; Snyder, Evan Y; Jamieson, Catriona H M; Mattrey, Robert F

2012-01-01

315

Expanding hollow metal rings  

DOEpatents

A sealing device that may expand more planar dimensions due to internal thermal expansion of a filler material. The sealing material is of a composition such that when desired environment temperatures and internal actuating pressures are reached, the sealing materials undergoes a permanent deformation. For metallic compounds, this permanent deformation occurs when the material enters the plastic deformation phase. Polymers, and other materials, may be using a sealing mechanism depending on the temperatures and corrosivity of the use. Internal pressures are generated by either rapid thermal expansion or material phase change and may include either liquid or solid to gas phase change, or in the gaseous state with significant pressure generation in accordance with the gas laws. Sealing material thickness and material composition may be used to selectively control geometric expansion of the seal such that expansion is limited to a specific facing and or geometric plane.

Peacock, Harold B. (Evans, GA); Imrich, Kenneth J. (Grovetown, GA)

2009-03-17

316

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

317

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

318

Centrifugal piston expander  

SciTech Connect

The improved method and apparatus for operating a centrifugal piston expander of the type wherein a free piston is mounted in a rotating fluid pressure chamber having a longitudinal axis that is non-radial with respect to the axis of rotation, but extends from a position remote from the rotation axis to a position proximate to the rotation axis. To bring the free piston to a cushioned stop when it is moving radially inwardly under the influence of applied gas pressure, a normally open exhaust valve in the inner end of the fluid pressure chamber is closed to trap a column of gas in the path of the oncoming piston. After the inward motion of the piston is arrested, the valve may be opened to exhaust the trapped gas or may be maintained closed for a brief period to permit the energy stored in the trapped gas to initiate the acceleration of the piston in its return outward movement.

Dibrell, E. W.

1985-04-30

319

Diffusion-weighted MR imaging with single-shot echo-planar imaging in the upper abdomen: preliminary clinical experience in 61 patients  

Microsoft Academic Search

Background: To determine the potential ability of diffusion-weighted magnetic resonance (MR) imaging with single-shot echo-planar imaging\\u000a (DW imaging) in the upper abdomen by apparent diffusion coefficient (ADC) and signal:intensity ratio (SIR) measurements.\\u000a \\u000a \\u000a \\u000a \\u000a Methods: DW imaging was performed in 61 clinical patients. ADCs in the liver, pancreas, spleen, kidney, and different pathological\\u000a conditions were calculated. Spleen-to-liver SIR and segmental intensity difference

T. Ichikawa; H. Haradome; J. Hachiya; T. Nitatori; T. Araki

1999-01-01

320

Dynamic infrared imaging of cutaneous melanoma and normal skin in patients treated with BNCT.  

PubMed

We recently initiated a program aimed to investigate the suitability of dynamic infrared imaging for following-up nodular melanoma patients treated with BNCT. The reason that makes infrared imaging attractive is the fact that it constitutes a functional and non-invasive imaging method, providing information on the normal and abnormal physiologic response of the nervous and vascular systems, as well as the local metabolic rate and inflammatory processes that ultimately appear as differences in the skin temperature. An infrared camera, with a focal plane array of 320 x 240 uncooled ferroelectric detectors is employed, which provides a video stream of the infrared emission in the 7-14 microm wavelength band. A double blackbody is used as reference for absolute temperature calibration. After following a protocol for patient preparation and acclimatization, a basal study is performed. Subsequently, the anatomic region of interest is subjected to a provocation test (a cold stimulus), which induces an autonomic vasoconstriction reflex in normal structures, thus enhancing the thermal contrast due to the differences in the vasculature of the different skin regions. Radiation erythema reactions and melanoma nodules possess typically a faster temperature recovery than healthy, non-irradiated skin. However, some other non-pathological structures are also detectable by infrared imaging, (e.g. scars, vessels, arteriovenous anastomoses and injuries), thus requiring a multi-study comparison in order to discriminate the tumor signal. Besides the superficial nodules, which are readily noticeable by infrared imaging, we have detected thermal signals that are coincident with the location of non-palpable nodules, which are observable by CT and ultrasound. Diffuse regions of fast temperature recovery after a cold stimulus were observed between the third and sixth weeks post-BNCT, concurrent with the clinical manifestation of radiation erythema. The location of the erythematous visible and infrared regions is consistent with the 3D dosimetry calculations. PMID:19380232

Santa Cruz, G A; Bertotti, J; Marín, J; González, S J; Gossio, S; Alvarez, D; Roth, B M C; Menéndez, P; Pereira, M D; Albero, M; Cubau, L; Orellano, P; Liberman, S J

2009-07-01

321

Autofluorescence imaging and narrow-band imaging for the detection of early neoplasia in patients with Barrett's esophagus.  

PubMed

High-resolution endoscopy (HRE), magnifying endoscopy, auto-fluorescence endoscopy, and narrow-band imaging (NBI) are promising techniques that could improve the detection of early neoplasia and the efficacy of endoscopic surveillance in patients with Barrett's esophagus. HRE improves the detection of lesions by white light, and video autofluorescence imaging (AFI) may have additional value in terms of sensitivity. The strengths ofAFI are its high sensitivity and a high negative predictive value,while potential limitations are its moderate specificity and positive predictive value. NBI enhances the mucosal and vascular patterns (i. e. the mucosal morphology) without the need for chromoendoscopy. The mucosal morphology features may be used to distinguish early neoplasia from nondysplastic Barrett's esophagus. Magnification is required for optimal use of NBI,which is a limitation of this technique. NBI with magnifying endoscopy could, however, be used for targeted inspection of lesions detected first by HRE or AFI. This approach has been shown to reduce the false-positive rate associated with AFI while maintaining its high sensitivity. To date, AFI and NBI have been used separately in two different prototypes, but a prototype endoscope that incorporates all of these techniques has recently become available. It is expected that future refinement of the autofluorescence and narrow-band modules may further increase their diagnostic value and ultimately improve the effectiveness of surveillance of Barrett's esophagus. PMID:16802271

Kara, M A; Bergman, J J

2006-06-01

322

[Self concept and parental images in patients with affective disorders--a clinical study with the Giessen Test].  

PubMed

The relationship between self, ideal self and normative self was studied in a sample of 139 patients with affective disorders and 73 patients with orthopaedic complaints. The depressive patients showed significant-asymmetric relationships between self and ideal self even after recovery from the clinical depression. Neurotic depressive patients could be distinguished from unipolar depressive patients in this regard. The self-concept of the depressive patients was characterised by means of the bipolar Giessen-test dimensions "insufficiency of performance", "lack of social adjustment" and "lack of social contact" and by means of the GT-dimensions "negative social resonance" and "depressive mood". There were no specific relationships between self-image and parental images in the depressive sample. The results underline the necessity of therapeutic interventions in depressive patients during the so-called symptom-free interval. PMID:10780159

Böker, H; Budischewski, K; Walesch, K; Nikisch, G

2000-01-01

323

Adaptive optics-assisted optical coherence tomography for imaging of patients with age related macular degeneration  

NASA Astrophysics Data System (ADS)

We developed an optical coherence tomography (OCT) prototype with a sample arm that uses a 3.4 mm beam, which is considerably larger than the 1.2 to 1.5 mm beam that is used in commercialized OCT systems. The system is equipped with adaptive optics (AO), and to distinguish it from traditional AO-OCT systems with a larger 6 mm beam we have coined this concept AO-assisted OCT. Compared to commercialized OCT systems, the 3.4 mm aperture combined with AO improves light collection efficiency and imaging lateral resolution. In this paper, the performance of the AOa-OCT system was compared to a standard OCT system and demonstrated for imaging of age-related macular degeneration (AMD). Measurements were performed on the retinas of three human volunteers with healthy eyes and on one eye of a patient diagnosed with AMD. The AO-assisted OCT system imaged retinal structures of healthy human eyes and a patient eye affected by AMD with higher lateral resolution and a 9° by 9° field of view. This combination of a large isoplanatic patch and high lateral resolution can be expected to fill a gap between standard OCT with a 1.2 mm beam and conventional AO-OCT with a 6 mm beam and a 1.5° by 1.5° isoplanatic patch.

Sudo, Kenta; Cense, Barry

2013-03-01

324

Multiphase CT Angiography: A New Tool for the Imaging Triage of Patients with Acute Ischemic Stroke.  

PubMed

Purpose To describe the use of an imaging selection tool, multiphase computed tomographic (CT) angiography, in patients with acute ischemic stroke (AIS) and to demonstrate its interrater reliability and ability to help determine clinical outcome. Materials and Methods The local ethics board approved this study. Data are from the pilot phase of PRoveIT, a prospective observational study analyzing utility of multimodal imaging in the triage of patients with AIS. Patients underwent baseline unenhanced CT, single-phase CT angiography of the head and neck, multiphase CT angiography, and perfusion CT. Multiphase CT angiography generates time-resolved images of pial arteries. Pial arterial filling was scored on a six-point ordinal scale, and interrater reliability was tested. Clinical outcomes included a 50% or greater decrease in National Institutes of Health Stroke Scale (NIHSS) over 24 hours and 90-day modified Rankin Scale (mRS) score of 0-2. The ability to predict clinical outcomes was compared between single-phase CT angiography, multiphase CT angiography, and perfusion CT by using receiver operating curve analysis, Akaike information criterion (AIC), and Bayesian information criterion (BIC). Results A total of 147 patients were included. Interrater reliability for multiphase CT angiography is excellent (n = 30, ? = 0.81, P < .001). At receiver operating characteristic curve analysis, the ability to predict clinical outcome is modest (C statistic = 0.56, 95% confidence interval [CI]: 0.52, 0.63 for ?50% decrease in NIHSS over 24 hours; C statistic = 0.6, 95% CI: 0.53, 0.68 for 90-day mRS score of 0-2) but better than that of models using single-phase CT angiography and perfusion CT (P < .05 overall). With AIC and BIC, models that use multiphase CT angiography are better than models that use single-phase CT angiography and perfusion CT for a decrease of 50% or more in NIHSS over 24 hours (AIC = 166, BIC = 171.7; values were lowest for multiphase CT angiography) and a 90-day mRS score of 0-2 (AIC = 132.1, BIC = 137.4; values were lowest for multiphase CT angiography). Conclusion Multiphase CT angiography is a reliable tool for imaging selection in patients with AIS. (©) RSNA, 2015 Online supplemental material is available for this article. PMID:25633505

Menon, Bijoy K; d'Esterre, Christopher D; Qazi, Emmad M; Almekhlafi, Mohammed; Hahn, Leszek; Demchuk, Andrew M; Goyal, Mayank

2015-05-01

325

Prevalence and Imaging Characteristics of Palatine Tonsilloliths Detected by CT in 2,873 Consecutive Patients  

PubMed Central

Aim. Tonsilloliths are calcified structures that develop in tonsillar crypts. They are commonly detected in daily clinical practice. The prevalence of tonsilloliths was 16 to 24% in previous reports, but it is inconsistent with clinical experience. The aim of this study is to clarify the prevalence, number, and size distribution of tonsilloliths using computed tomography (CT) in a relatively large number of patients. Materials and Methods. We retrospectively reviewed the scans of 2,873 patients referred for CT examinations with regard to tonsilloliths. Results. Palatine tonsilloliths were found in 1,145 out of 2,873 patients (39.9%). The prevalence of tonsilloliths increased with age, and most commonly in patients of ages 50–69. The prevalence in the 30s and younger was statistically lower than in the 40s and older (P < 0.05). The number of tonsilloliths per palatine tonsil ranged from one to 18. The size of the tonsilloliths ranged from 1 to 10?mm. For the patients with multiple CT examinations,the number of tonsilloliths increased in 51 (3.9%) and decreased in 84 (6.5%) of the tonsils. Conclusions. As palatine tonsilloliths are common conditions, screenings for tonsilloliths during the diagnosis of soft tissue calcifications should be included in routine diagnostic imaging. PMID:25389536

Takahashi, Akira; Sugawara, Chieko; Kudoh, Takaharu; Uchida, Daisuke; Tamatani, Tetsuya; Nagai, Hirokazu; Miyamoto, Youji

2014-01-01

326

Dynamic contrast–enhanced magnetic resonance imaging in patients with pulmonary arterial hypertension  

PubMed Central

Abstract Dynamic contrast–enhanced (DCE) time-resolved magnetic resonance (MR) imaging is a technique whereby the passage of an intravenous contrast bolus can be tracked through the pulmonary vascular system. The aim of this study was to investigate the prognostic significance of DCE-MR pulmonary blood transit times in patients with pulmonary arterial hypertension (PAH). Seventy-nine patients diagnosed with PAH underwent pulmonary DCE imaging at 1.5 T using a time-resolved three-dimensional spoiled gradient echo sequence. The prognostic significance of two DCE parameters, full width at half maximum (FWHM) of the first-pass clearance curve and pulmonary transit time (PTT), along with demographic and invasive catheter measurements, was evaluated by univariate and bivariate Cox proportional hazards regression and Kaplan-Meier analysis. DCE-MR transit times were most closely correlated with cardiac index (CI) and pulmonary vascular resistance index (PVRI) and were both found to be accurate for detecting reduced CI (FWHM area under the curve [AUC] at receiver operating characteristic analysis = 0.91 and PTT AUC = 0.92, respectively) and for detecting elevated PVRI (FWHM AUC = 0.88 and PTT AUC = 0.84, respectively). During the follow-up period, 25 patients died. Patients with longer measurements of FWHM (P = 0.0014) and PTT (P = 0.004) were associated with poor outcome at Kaplan-Meier analysis, and both parameters were strong predictors of adverse outcome from Cox proportional hazards analysis (P = 0.013 and 0.010, respectively). At bivariate analysis, DCE measurements predicted mortality independent of age, gender, and World Health Organization functional class; however, invasive hemodynamic indexes CI, PVRI, and DCE measurements were not independent of one another. In conclusion, DCE-MR transit times predict mortality in patients with PAH and are closely associated with clinical gold standards CI and PVRI. PMID:25006422

Condliffe, Robin; Marshall, Helen; Elliot, Charlie; Kiely, David G.; Wild, Jim M.

2014-01-01

327

Dynamic contrast-enhanced magnetic resonance imaging in patients with pulmonary arterial hypertension.  

PubMed

Dynamic contrast-enhanced (DCE) time-resolved magnetic resonance (MR) imaging is a technique whereby the passage of an intravenous contrast bolus can be tracked through the pulmonary vascular system. The aim of this study was to investigate the prognostic significance of DCE-MR pulmonary blood transit times in patients with pulmonary arterial hypertension (PAH). Seventy-nine patients diagnosed with PAH underwent pulmonary DCE imaging at 1.5 T using a time-resolved three-dimensional spoiled gradient echo sequence. The prognostic significance of two DCE parameters, full width at half maximum (FWHM) of the first-pass clearance curve and pulmonary transit time (PTT), along with demographic and invasive catheter measurements, was evaluated by univariate and bivariate Cox proportional hazards regression and Kaplan-Meier analysis. DCE-MR transit times were most closely correlated with cardiac index (CI) and pulmonary vascular resistance index (PVRI) and were both found to be accurate for detecting reduced CI (FWHM area under the curve [AUC] at receiver operating characteristic analysis = 0.91 and PTT AUC = 0.92, respectively) and for detecting elevated PVRI (FWHM AUC = 0.88 and PTT AUC = 0.84, respectively). During the follow-up period, 25 patients died. Patients with longer measurements of FWHM (P = 0.0014) and PTT (P = 0.004) were associated with poor outcome at Kaplan-Meier analysis, and both parameters were strong predictors of adverse outcome from Cox proportional hazards analysis (P = 0.013 and 0.010, respectively). At bivariate analysis, DCE measurements predicted mortality independent of age, gender, and World Health Organization functional class; however, invasive hemodynamic indexes CI, PVRI, and DCE measurements were not independent of one another. In conclusion, DCE-MR transit times predict mortality in patients with PAH and are closely associated with clinical gold standards CI and PVRI. PMID:25006422

Swift, Andrew J; Telfer, Adam; Rajaram, Smitha; Condliffe, Robin; Marshall, Helen; Capener, Dave; Hurdman, Judith; Elliot, Charlie; Kiely, David G; Wild, Jim M

2014-03-01

328

A protocol for magnetic resonance imaging of the temporomandibular joints.  

PubMed

The complex concepts and procedures of magnetic resonance imaging (MRI) are unfamiliar to many dentists. Similarly, many radiologists lack understanding of the clinical requirements of the dentist for accurate assessment of TMJ abnormalities. Thus, TMJ imaging procedures may be inadequate or incomplete, may vary from facility to facility, and sometimes from patient to patient in a given facility. A protocol for TMJ imaging is presented which meets dental requirements and is rapidly performed in the MRI facility. The protocol may be copied and attached to the prescription to the imaging center. It may be modified or expanded to accommodate specific patient requirements or equipment performance. PMID:10029751

Gibbs, S J; Simmons, H C

1998-10-01

329

Technetium-99m (v) dimercaptosuccinic acid uptake in patients with head and neck squamous carcinoma: Experience in imaging  

SciTech Connect

A recently developed imaging agent, technetium-99m (v) dimercaptosuccinic acid (/sup 99m/Tc (v) DMSA), has been used to assess head and neck squamous carcinoma (SCC). We have prospectively studied 62 patients of whom 53 had a histologically proven head and neck SCC. The remaining nine had benign lesions. The results of planar imaging in patients with primary disease yielded an 85% sensitivity and 78% specificity. Planar imaging in patients with cervical lymphadenopathy revealed a 59% sensitivity. Nineteen patients also had single photon emission computed tomography imaging which improved the image quality, spatial resolution and sensitivity of the investigation. Twenty-seven patients were scanned before and after radiotherapy and, of these, 96% showed positive uptake in the salivary glands with no evidence of tumor recurrence. This study has shown /sup 99m/Tc (v) DMSA imaging provides a cheap and rapid method of investigating head and neck SCC and further studies are necessary to evaluate its role in the management of patients with this disease.

Watkinson, J.C.; Lazarus, C.R.; Mistry, R.; Shaheen, O.H.; Maisey, M.N.; Clarke, S.E.

1989-02-01

330

Observer success rates for identification of 3D surface reconstructed facial images and implications for patient privacy and security  

NASA Astrophysics Data System (ADS)

3D and multi-planar reconstruction of CT images have become indispensable in the routine practice of diagnostic imaging. These tools cannot only enhance our ability to diagnose diseases, but can also assist in therapeutic planning as well. The technology utilized to create these can also render surface reconstructions, which may have the undesired potential of providing sufficient detail to allow recognition of facial features and consequently patient identity, leading to violation of patient privacy rights as described in the HIPAA (Health Insurance Portability and Accountability Act) legislation. The purpose of this study is to evaluate whether 3D reconstructed images of a patient's facial features can indeed be used to reliably or confidently identify that specific patient. Surface reconstructed images of the study participants were created used as candidates for matching with digital photographs of participants. Data analysis was performed to determine the ability of observers to successfully match 3D surface reconstructed images of the face with facial photographs. The amount of time required to perform the match was recorded as well. We also plan to investigate the ability of digital masks or physical drapes to conceal patient identity. The recently expressed concerns over the inability to truly "anonymize" CT (and MRI) studies of the head/face/brain are yet to be tested in a prospective study. We believe that it is important to establish whether these reconstructed images are a "threat" to patient privacy/security and if so, whether minimal interventions from a clinical perspective can substantially reduce this possibility.

Chen, Joseph J.; Siddiqui, Khan M.; Fort, Leslie; Moffitt, Ryan; Juluru, Krishna; Kim, Woojin; Safdar, Nabile; Siegel, Eliot L.

2007-03-01

331

In vivo molecular imaging of chemokine receptor CXCR4 expression in patients with advanced multiple myeloma  

PubMed Central

CXCR4 is a G-protein-coupled receptor that mediates recruitment of blood cells toward its ligand SDF-1. In cancer, high CXCR4 expression is frequently associated with tumor dissemination and poor prognosis. We evaluated the novel CXCR4 probe [68Ga]Pentixafor for in vivo mapping of CXCR4 expression density in mice xenografted with human CXCR4-positive MM cell lines and patients with advanced MM by means of positron emission tomography (PET). [68Ga]Pentixafor PET provided images with excellent specificity and contrast. In 10 of 14 patients with advanced MM [68Ga]Pentixafor PET/CT scans revealed MM manifestations, whereas only nine of 14 standard [18F]fluorodeoxyglucose PET/CT scans were rated visually positive. Assessment of blood counts and standard CD34+ flow cytometry did not reveal significant blood count changes associated with tracer application. Based on these highly encouraging data on clinical PET imaging of CXCR4 expression in a cohort of MM patients, we conclude that [68Ga]Pentixafor PET opens a broad field for clinical investigations on CXCR4 expression and for CXCR4-directed therapeutic approaches in MM and other diseases. PMID:25736399

Philipp-Abbrederis, Kathrin; Herrmann, Ken; Knop, Stefan; Schottelius, Margret; Eiber, Matthias; Lückerath, Katharina; Pietschmann, Elke; Habringer, Stefan; Gerngroß, Carlos; Franke, Katharina; Rudelius, Martina; Schirbel, Andreas; Lapa, Constantin; Schwamborn, Kristina; Steidle, Sabine; Hartmann, Elena; Rosenwald, Andreas; Kropf, Saskia; Beer, Ambros J; Peschel, Christian; Einsele, Hermann; Buck, Andreas K; Schwaiger, Markus; Götze, Katharina; Wester, Hans-Jürgen; Keller, Ulrich

2015-01-01

332

Fusion of SPECT and Multidetector CT Images for Accurate Localization of Pelvic Sentinel Lymph Nodes in Prostate Cancer Patients  

Microsoft Academic Search

Objective: The present study was performed to investigate the feasibility of fusion of images obtained by SPECT and multidetector CT (MDCT) for the accurate localization of sentinel lymph nodes in prostate cancer patients. Methods: To facilitate the fusion of both SPECT and CT images, a pelvic MDCT scan was performed with 3 markers of small plastic bullets attached to the

Hiroto Kizu; Teruhiko Takayama; Mamoru Fukuda; Masayuki Egawa; Hiroyuki Tsushima; Masato Yamada; Kenji Ichiyanagi; Kunihiko Yokoyama; Masahisa Onoguchi; Norihisa Tonami

333

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

334

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

335

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

NASA Astrophysics Data System (ADS)

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 tumor volume and radiotracer uptake variations. The proposed approach is based on multi-observation image analysis for merging several PET acquisitions to assess tumor metabolic volume and uptake variations. The fusion algorithm is based on iterative estimation using a 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 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-tracer datasets in order to evaluate its potential impact on the biological tumor volume definition for radiotherapy applications.

David, S.; Visvikis, D.; Roux, C.; Hatt, M.

2011-09-01

336

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

PubMed

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 tumor volume and radiotracer uptake variations. The proposed approach is based on multi-observation image analysis for merging several PET acquisitions to assess tumor metabolic volume and uptake variations. The fusion algorithm is based on iterative estimation using a 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 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-tracer datasets in order to evaluate its potential impact on the biological tumor volume definition for radiotherapy applications. PMID:21846937

David, S; Visvikis, D; Roux, C; Hatt, M

2011-09-21

337

Automated classification of patients with coronary artery disease using grayscale features from left ventricle echocardiographic images.  

PubMed

Coronary Artery Disease (CAD), caused by the buildup of plaque on the inside of the coronary arteries, has a high mortality rate. To efficiently detect this condition from echocardiography images, with lesser inter-observer variability and visual interpretation errors, computer based data mining techniques may be exploited. We have developed and presented one such technique in this paper for the classification of normal and CAD affected cases. A multitude of grayscale features (fractal dimension, entropies based on the higher order spectra, features based on image texture and local binary patterns, and wavelet based features) were extracted from echocardiography images belonging to a huge database of 400 normal cases and 400 CAD patients. Only the features that had good discriminating capability were selected using t-test. Several combinations of the resultant significant features were used to evaluate many supervised classifiers to find the combination that presents a good accuracy. We observed that the Gaussian Mixture Model (GMM) classifier trained with a feature subset made up of nine significant features presented the highest accuracy, sensitivity, specificity, and positive predictive value of 100%. We have also developed a novel, highly discriminative HeartIndex, which is a single number that is calculated from the combination of the features, in order to objectively classify the images from either of the two classes. Such an index allows for an easier implementation of the technique for automated CAD detection in the computers in hospitals and clinics. PMID:23958645

Acharya, U Rajendra; Sree, S Vinitha; Muthu Rama Krishnan, M; Krishnananda, N; Ranjan, Shetty; Umesh, Pai; Suri, Jasjit S

2013-12-01

338

[A review of the position adopted by patients when acquiring images of the base of the hamate hook].  

PubMed

The hamate bone, one of the carpal (wrist) bones, has a large uncinate process protruding from the palm side. In sports such as golf and tennis, the hamate bone can break if is subjected to a high external force, such as from the handle of a racquet or club. At our hospital we take X-ray images of the hamate bone from two directions: an axial image through the carpal tunnel and an image at the base of the hamate hook (conventional method). While the conventional method makes it easy to create images of the base of the hamate hook, the patient may suffer pain during image-taking because the hamate bone is pulled to cause radial flexion. We therefore investigated a method of imaging that would create three-dimensional computed tomography (3DCT) images of the base of the hamate hook in which the patient would only have to only rotate the wrist externally and elevate the fore-arm without any radial flexion. Our results suggest that it is possible to obtain images of the base of the hamate hook as clear as those acquired using the conventional method with the patient in a comfortable and painless position taking images at an external rotation angle of 50.3° and a forearm elevation angle of 20.3°. PMID:24953320

Takamatsu, Shunsuke; Miyakawa, Seiichirou; Sato, Hisaya; Suzuki, Wataru; Nishizawa, Takeshi; Nakamura, Masami; Umeda, Hirotaka; Sai, Shogo; Kato, Kyoichi; Nakazawa, Yasuo; Ikeda, Jun

2014-06-01

339

SU-E-J-86: Lobar Lung Function Quantification by PET Galligas and CT Ventilation Imaging in Lung Cancer Patients  

SciTech Connect

Purpose: The purpose of this study was to quantify the lobar lung function using the novel PET Galligas ([68Ga]-carbon nanoparticle) ventilation imaging and the investigational CT ventilation imaging in lung cancer patients pre-treatment. Methods: We present results on our first three lung cancer patients (2 male, mean age 78 years) as part of an ongoing ethics approved study. For each patient a PET Galligas ventilation (PET-V) image and a pair of breath hold CT images (end-exhale and end-inhale tidal volumes) were acquired using a Siemens Biograph PET CT. CT-ventilation (CT-V) images were created from the pair of CT images using deformable image registration (DIR) algorithms and the Hounsfield Unit (HU) ventilation metric. A comparison of ventilation quantification from each modality was done on the lobar level and the voxel level. A Bland-Altman plot was used to assess the difference in mean percentage contribution of each lobe to the total lung function between the two modalities. For each patient, a voxel-wise Spearmans correlation was calculated for the whole lungs between the two modalities. Results: The Bland-Altman plot demonstrated strong agreement between PET-V and CT-V for assessment of lobar function (r=0.99, p<0.001; range mean difference: ?5.5 to 3.0). The correlation between PET-V and CT-V at the voxel level was moderate(r=0.60, p<0.001). Conclusion: This preliminary study on the three patients data sets demonstrated strong agreement between PET and CT ventilation imaging for the assessment of pre-treatment lung function at the lobar level. Agreement was only moderate at the level of voxel correlations. These results indicate that CT ventilation imaging has potential for assessing pre-treatment lobar lung function in lung cancer patients.

Eslick, E; Kipritidis, J; Keall, P [University of Sydney, Camperdown, NSW (Australia); Bailey, D; Bailey, E [Royal North Shore Hospital, St. Leonards, NSW (Australia)

2014-06-01

340

Segmentation of Individual Renal Cysts from MR Images in Patients with Autosomal Dominant Polycystic Kidney Disease  

PubMed Central

Summary Objective To evaluate the performance of a semi-automated method for the segmentation of individual renal cysts from magnetic resonance (MR) images in patients with autosomal dominant polycystic kidney disease (ADPKD). Design, setting, participants, & measurements This semi-automated method was based on a morphologic watershed technique with shape-detection level set for segmentation of renal cysts from MR images. T2-weighted MR image sets of 40 kidneys were selected from 20 patients with mild to moderate renal cyst burden (kidney volume < 1500 ml) in the Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP). The performance of the semi-automated method was assessed in terms of two reference metrics in each kidney: the total number of cysts measured by manual counting and the total volume of cysts measured with a region-based thresholding method. The proposed and reference measurements were compared using intraclass correlation coefficient (ICC) and Bland-Altman analysis. Results Individual renal cysts were successfully segmented with the semi-automated method in all 20 cases. The total number of cysts in each kidney measured with the two methods correlated well (ICC, 0.99), with a very small relative bias (0.3% increase with the semi-automated method; limits of agreement, 15.2% reduction to 17.2% increase). The total volume of cysts measured using both methods also correlated well (ICC, 1.00), with a small relative bias of <10% (9.0% decrease in the semi-automated method; limits of agreement, 17.1% increase to 43.3% decrease). Conclusion This semi-automated method to segment individual renal cysts in ADPKD kidneys provides a quantitative indicator of severity in early and moderate stages of the disease. PMID:23520042

Bae, Kyungsoo; Park, Bumwoo; Sun, Hongliang; Wang, Jinhong; Tao, Cheng; Chapman, Arlene B.; Torres, Vicente E.; Grantham, Jared J.; Mrug, Michal; Bennett, William M.; Flessner, Michael F.; Landsittel, Doug P.

2013-01-01

341

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

342

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

343

No loss of cartilage volume over three years in patients with knee osteoarthritis as assessed by magnetic resonance imaging  

Microsoft Academic Search

Objective Magnetic resonance imaging (MRI) has the potential to provide accurate quantification of structural changes in joint disease, with sensitivity to change, as it can provide direct visualization of the cartilage and bone. In this study, we investigated whether knee cartilage volume, as assessed by MRI, is sensitive to change over time in patients with osteoarthritis (OA).Design Sixteen patient volunteers

S. J. Gandy; P. A. Dieppe; M. C. Keen; R. A. Maciewicz; I. Watt; J. C. Waterton

2002-01-01

344

Patient dose from kilovoltage cone beam computed tomography imaging in radiation therapy  

SciTech Connect

Kilovoltage cone-beam computerized tomography (kV-CBCT) systems integrated into the gantry of linear accelerators can be used to acquire high-resolution volumetric images of the patient in the treatment position. Using on-line software and hardware, patient position can be determined accurately with a high degree of precision and, subsequently, set-up parameters can be adjusted to deliver the intended treatment. While the patient dose due to a single volumetric imaging acquisition is small compared to the therapy dose, repeated and daily image guidance procedures can lead to substantial dose to normal tissue. The dosimetric properties of a clinical CBCT system have been studied on an Elekta linear accelerator (Synergy[reg] RP, XVI system) and additional measurements performed on a laboratory system with identical geometry. Dose measurements were performed with an ion chamber and MOSFET detectors at the center, periphery, and surface of 30 and 16-cm-diam cylindrical shaped water phantoms, as a function of x-ray energy and longitudinal field-of-view (FOV) settings of 5,10,15, and 26 cm. The measurements were performed for full 360 deg.CBCT acquisition as well as for half-rotation scans for 120 kVp beams using the 30-cm-diam phantom. The dose at the center and surface of the body phantom were determined to be 1.6 and 2.3 cGy for a typical imaging protocol, using full rotation scan, with a technique setting of 120 kVp and 660 mAs. The results of our measurements have been presented in terms of a dose conversion factor f{sub CBCT}, expressed in cGy/R. These factors depend on beam quality and phantom size as well as on scan geometry and can be utilized to estimate dose for any arbitrary mAs setting and reference exposure rate of the x-ray tube at standard distance. The results demonstrate the opportunity to manipulate the scanning parameters to reduce the dose to the patient by employing lower energy (kVp) beams, smaller FOV, or by using half-rotation scan.

Islam, Mohammad K.; Purdie, Thomas G.; Norrlinger, Bernhard D.; Alasti, Hamideh; Moseley, Douglas J.; Sharpe, Michael B.; Siewerdsen, Jeffrey H.; Jaffray, David A. [Department of Radiation Physics, Princess Margaret Hospital and Department of Radiation Oncology, University of Toronto, Toronto (Canada); Department of Radiation Physics, Princess Margaret Hospital and Department of Radiation, University of Toronto, Toronto (Canada); Department of Radiation Physics, Princess Margaret Hospital, Toronto (Canada); Department of Radiation Physics, Princess Margaret Hospital and Department of Radiation Oncology, University of Toronto, Toronto (Canada); Ontario Cancer Institute Princess Margaret Hospital and Department of Medical Biophysics, University of Toronto, Toronto (Canada); Department of Radiation Physics and Ontario Cancer Institute, Princess Margaret Hospital and Department of Radiation Oncology and Department of Medical Biophysics, University of Toronto, Toronto (Canada)

2006-06-15

345

FDG PET images in a patient with Erdheim-Chester Disease  

PubMed Central

Erdheim-Chester disease (ECD) is an uncommon non-Langerhans-cell histiocytosis, due to excessive production of histiocytes deposited in various organs and tissues in the human body. FDG PET was performed in a 68-year-old man with documented active ECD to evaluate the extent of the disease. The patient was previously treated with high dose subcutaneous Interferon alpha 2b, 1,000,000 units 3 times a week, but treatment was interrupted approximately 5 weeks prior to evaluation at NIH due to side effects of the medication. FDG PET/CT showed lesions were imaged in brain, heart, mediastinum and abdomen. PMID:23640213

Sioka, Chrissa; Estrada-Veras, Juvianee; Maric, Irinia; Gahl, William A.; Chen, Clara C.

2013-01-01

346

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

347

Reversibly expanded encapsulation complexes.  

PubMed

Synthetic receptors that surround their target molecules - self assembled capsules and deep cavitands - have emerged as the most realistic models of enzymes active sites. They were introduced to study the behaviour of molecules isolated in small spaces and it has become increasingly clear that the behavior of molecules in dilute aqueous solution does not reflect their behavior in confimed spaces. The synthetic receptors fold around their target guests, isolate them from the bulk solvent, provide a hydrophobic environment and present the guests with each other in a limited space. These features combine to show high binding selectivity, large rate from the ground up; they are designed, synthesized then tested. In recent years, we have found a short-cut to total synthesis; some capsules readily insert spacer elements in the presence of suitable guests that fill the enlarged spaces. This expands the repertoire of containers and the present review describes their structures, the nature of the spaces inside, the exchange dynamics, and the rules that govern their formation. PMID:22048687

Ajami, Dariush; Rebek, Julius

2012-01-01

348

Radionuclide scrotal imaging: further experience with 210 patients. Part I. Anatomy, pathophysiology, and methods  

SciTech Connect

Ten years' experience with radionuclide scrotal imaging (RSI) to evaluate perfusion of the scrotal contents has confirmed the value of this examination. In 1973, Nadel et al. first proposed using sodium pertechnetate (Tc-99m) to diagnose testicular torsion. By the end of 1982, more than thirty articles have been published on this topic, with most emphasizing the usefulness of RSI in managing patients with acute scrotal pain. The present communication describes our findings in 210 patients, not previously reported. There were four groups with relatively distinct clinical presentations: (a) acute scrotal pain, (b) chronic scrotal pain, (c) scrotal injury, and (d) scrotal mass. The anatomic and pathophysiologic bases for the scan findings will be emphasized. We discuss the staging of testicular torsion; viability of the compromised testicle; variability in the presentation of acute infection; anatomy of trauma, varicocele, and inguinal hernia; and the correlation with scrotal sonography.

Chen, D.C.P.; Holder, L.E.; Melloul, M.

1983-08-01

349

Hybrid PET/MR imaging in two sarcoma patients – clinical benefits and implications for future trials  

PubMed Central

PET/MRI is an evolving hybrid imaging modality which combines the inherent strengths of MRIs soft-tissue and contrast resolution and PETs functional metabolic capabilities. Bone and soft-tissue sarcoma are a relatively rare tumor entity, relying on MRI for local staging and often on PET/CT for lymph node involvement and metastatic spread evaluation. The purpose of this article is to demonstrate the successful use of PET/MRI in two sarcoma patients. We also use these patients as a starting point to discuss how PET/MRI might be of value in sarcoma. Among its potential benefits are: superior TNM staging than either modality alone, decreased radiation dose, more sensitive and specific follow-up and better assessment of treatment response. These potentials need to be investigated in future PET/MRI soft-tissue sarcoma trials. PMID:24753758

Partovi, Sasan; Kohan, Andres A; Zipp, Lisa; Faulhaber, Peter; Kosmas, Christos; Ros, Pablo R; Robbin, Mark R

2014-01-01

350

Value of planar 201Tl imaging in risk stratification of patients recovering from acute myocardial infarction  

SciTech Connect

Although exercise ECG testing has been shown to have important prognostic value after acute myocardial infarction, exercise 201Tl scintigraphy offers several potential advantages, including: (1) increased sensitivity for detecting residual myocardial ischemia; (2) the ability to localize ischemia to a specific area or areas subtended by a specific coronary artery; (3) the ability to identify exercise-induced left ventricular dysfunction, which is manifested by increased lung uptake or transient left ventricular dilation; and (4) more reliable risk stratification of individual patients. The more optimal prognostic efficiency of 201Tl scintigraphy partially results from the fact that the error rate in falsely classifying patients as low risk is significantly smaller with 201Tl scintigraphy than with stress ECG. Because of these substantial advantages, there seems to be adequate rationale for recommending exercise perfusion imaging rather than exercise ECG alone as the preferred method for evaluating mortality and morbidity risks after acute myocardial infarction.

Gibson, R.S.; Watson, D.D. (Medical Center, University of Virginia Health Sciences Center, Charlottesville (United States))

1991-09-01

351

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

352

Image-Based Modeling and Precision Medicine: Patient-Specific Carotid and Coronary Plaque Assessment and Predictions  

PubMed Central

Atherosclerotic plaques may rupture without warning and cause acute cardiovascular events such as heart attack and stroke. Current clinical screening tools are insufficient to identify those patients with risks early and prevent the adverse events from happening. Medical imaging and image-based modeling have made considerable progress in recent years in identifying plaque morphological and mechanical risk factors which may be used in developing improved patient screening strategies. The key steps and factors in image-based models for human carotid and coronary plaques were illustrated, as well as grand challenges facing the researchers in the field to develop more accurate screening tools. PMID:23362245

Yang, Chun; Zheng, Jie; Canton, Gador; Bach, Richard; Hatsukami, Thomas S.; Wang, Liang; Yang, Deshan; Billiar, Kristen L.; Yuan, Chun

2013-01-01

353

Comparison Between Infrared Optical and Stereoscopic X-Ray Technologies for Patient Setup in Image Guided Stereotactic Radiotherapy  

SciTech Connect

Purpose: To compare infrared (IR) optical vs. stereoscopic X-ray technologies for patient setup in image-guided stereotactic radiotherapy. Methods and Materials: Retrospective data analysis of 233 fractions in 127 patients treated with hypofractionated stereotactic radiotherapy was performed. Patient setup at the linear accelerator was carried out by means of combined IR optical localization and stereoscopic X-ray image fusion in 6 degrees of freedom (6D). Data were analyzed to evaluate the geometric and dosimetric discrepancy between the two patient setup strategies. Results: Differences between IR optical localization and 6D X-ray image fusion parameters were on average within the expected localization accuracy, as limited by CT image resolution (3 mm). A disagreement between the two systems below 1 mm in all directions was measured in patients treated for cranial tumors. In extracranial sites, larger discrepancies and higher variability were observed as a function of the initial patient alignment. The compensation of IR-detected rotational errors resulted in a significantly improved agreement with 6D X-ray image fusion. On the basis of the bony anatomy registrations, the measured differences were found not to be sensitive to patient breathing. The related dosimetric analysis showed that IR-based patient setup caused limited variations in three cases, with 7% maximum dose reduction in the clinical target volume and no dose increase in organs at risk. Conclusions: In conclusion, patient setup driven by IR external surrogates localization in 6D featured comparable accuracy with respect to procedures based on stereoscopic X-ray imaging.

Tagaste, Barbara, E-mail: tagaste@cnao.it [Division of Radiation Oncology, European Institute of Oncology, Milano (Italy); Centro Nazionale di Adroterapia Oncologica, Pavia (Italy); Riboldi, Marco [Centro Nazionale di Adroterapia Oncologica, Pavia (Italy); TBM Lab, Department of Bioengineering, Politecnico di Milano University, Milano (Italy); Spadea, Maria F. [TBM Lab, Department of Bioengineering, Politecnico di Milano University, Milano (Italy); Department of Experimental and Clinical Medicine, Universita degli Studi Magna Graecia, Catanzaro (Italy); Bellante, Simone [TBM Lab, Department of Bioengineering, Politecnico di Milano University, Milano (Italy); Baroni, Guido [Centro Nazionale di Adroterapia Oncologica, Pavia (Italy); TBM Lab, Department of Bioengineering, Politecnico di Milano University, Milano (Italy); Cambria, Raffaella; Garibaldi, Cristina [Medical Physics, European Institute of Oncology, Milano (Italy); Ciocca, Mario [Centro Nazionale di Adroterapia Oncologica, Pavia (Italy); Medical Physics, European Institute of Oncology, Milano (Italy); Catalano, Gianpiero [Division of Radiation Oncology, European Institute of Oncology, Milano (Italy); Unit of Radiotherapy, Multimedica Holding Clinical Institute, Castellanza (Italy); Alterio, Daniela [Division of Radiation Oncology, European Institute of Oncology, Milano (Italy); Orecchia, Roberto [Division of Radiation Oncology, European Institute of Oncology, Milano (Italy); Centro Nazionale di Adroterapia Oncologica, Pavia (Italy); Department of Science and Biomedical Technologies, Universita di Milano, Milano (Italy)

2012-04-01

354

Advanced expander test bed program  

NASA Technical Reports Server (NTRS)

The Advanced Expander Test Bed (AETB) is a key element in NASA's Chemical Transfer Propulsion Program for development and demonstration of expander cycle oxygen/hydrogen engine technology component technology for the next space engine. The AETB will be used to validate the high-pressure expander cycle concept, investigate system interactions, and conduct investigations of advanced missions focused components and new health monitoring techniques. 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.

Masters, A. I.; Mitchell, J. C.

1991-01-01

355

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

356

Multimodality Imaging to Predict Response to Systemic Treatment in Patients with Advanced Colorectal Cancer  

PubMed Central

Aim Aim of this study was to investigate the potential of 18F-FDG PET, diffusion weighted imaging (DWI) and susceptibility-weighted (T2*) MRI to predict response to systemic treatment in patients with colorectal liver metastases. The predictive values of pretreatment measurements and of early changes one week after start of therapy, were evaluated. Methods Imaging was performed prior to and one week after start of first line chemotherapy in 39 patients with colorectal liver metastases. 18F-FDG PET scans were performed on a PET/CT scanner and DWI and T2* were performed on a 1.5T MR scanner. The maximum standardized uptake values (SUV), total lesion glycolysis (TLG), apparent diffusion coefficient (ADC) and T2* value were assessed in the same lesions. Up to 5 liver metastases per patient were analyzed. Outcome measures were progression free survival (PFS), overall survival (OS) and size response. Results Pretreatment, high SUVmax, high TLG, low ADC and high T2* were associated with a shorter OS. Low pretreatment ADC value was associated with shorter PFS. After 1 week a significant drop in SUVmax and rise in ADC were observed. The drop in SUV was correlated with the rise in ADC (r=-0.58, p=0.002). Neither change in ADC nor in SUV was predictive of PFS or OS. T2* did not significantly change after start of treatment. Conclusion Pretreatment SUVmax, TLG, ADC, and T2* values in colorectal liver metastases are predictive of patient outcome. Despite sensitivity of DWI and 18F-FDG PET for early treatment effects, change in these parameters was not predictive of long term outcome. PMID:25831053

Heijmen, Linda; ter Voert, Edwin E. G. W.; Oyen, Wim J. G.; Punt, Cornelis J. A.; van Spronsen, Dick Johan; Heerschap, Arend; de Geus-Oei, Lioe-Fee; van Laarhoven, Hanneke W. M.

2015-01-01

357

Glutamate quantification in patients with supratentorial gliomas using chemical shift imaging.  

PubMed

This study aimed to evaluate and validate chemical shift imaging (CSI) for in vivo glutamate (Glu) quantification in patients with supratentorial gliomas. If validated, CSI could become an extremely useful tool to investigate metabolic dysfunction of Glu in excitotoxic neuropathologies. Quantitative CSI estimates of Glu concentrations were compared with known concentrations of Glu in aqueous phantom solutions. Forty-one patients with known or likely supratentorial gliomas underwent preoperative CSI. The spectra obtained were analyzed for Glu concentrations and Glu to creatine (Cr) ratios. These in vivo measurements were correlated against ex vivo Glu content quantified by high performance liquid chromatography (HPLC) measured in 65 resected brain tumor and peritumoral brain specimens. For the phantom solutions the CSI estimates of Glu concentration and the Glu/Cr ratios were highly correlated with known Glu concentration (r² ?=?0.95, p?=?0.002, and r² ?=?0.97, p?patients with supratentorial gliomas using CSI. The in vitro and in vivo results suggest that this has the potential to be a reliable quantitative imaging assay for brain tumor patients. This may have wide clinical research applications in a number of neurological disorders where Glu excitotoxicity and metabolic dysfunction are known to play a role in pathogenesis, including tumor associated epilepsy, epilepsy, stroke and neurotrauma. PMID:24664947

Liubinas, S V; Drummond, K J; Desmond, P M; Bjorksten, A; Morokoff, A P; Kaye, A H; O'Brien, T J; Moffat, B A

2014-05-01

358

The catatonic dilemma expanded  

Microsoft Academic Search

Catatonia is a common syndrome that was first described in the literature by Karl Kahlbaum in 1874. The literature is still developing and remains unclear on many issues, especially classification, diagnosis, and pathophysiology. Clinicians caring for psychiatric patients with catatonic syndromes continue to face many dilemmas in diagnosis and treatment. We discuss many of the common problems encountered in the

Heath R Penland; Natalie Weder; Rajesh R Tampi

2006-01-01

359

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

360

Virtual center for renal support: technological approach to patient physiological image.  

PubMed

The patient physiological image (PPI) is a novel concept which manages the knowledge of the virtual center for renal support (VCRS), currently being developed by the Biomedical Engineering Group of the University of Seville. PPI is a virtual "replica" of the patient, built by means of a mathematical model, which represents several physiological subsystems of a renal patient. From a technical point of view, PPI is a component-oriented software module based on cutting-edge modeling and simulation technology. This paper provides a methodological and technological approach to the PPI. Computational architecture of PPI-based VCRS is also described. This is a multi-tier and multi-protocol system. Data are managed by several ORDBMS instances. Communications design is based on the virtual private network (VPN) concept. Renal patients have a minimum reliable access to the VCRS through a public switch telephone network--X.25 gateway. Design complies with the universal access requirement, allowing an efficient and inexpensive connection even in rural environments and reducing computational requirements in the patient's remote access unit. VCRS provides support for renal patients' healthcare, increasing the quality and quantity of monitored biomedical signals, predicting events as hypotension or low dialysis dose, assisting further to avoid them by an online therapy modification and easing diagnostic tasks. An online therapy adjustment experiment simulation is presented. Finally, the presented system serves as a computational aid for research in renal physiology. This is achieved by an open and reusable modeling and simulation architecture which allows the interaction among models and data from different scales and computer platforms, and a faster transference of investigation models toward clinical applications. PMID:12542237

Prado, Manuel; Roa, Laura; Reina-Tosina, Javier; Palma, Alfonso; Milán, José Antonio

2002-12-01

361

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

362

Quantitative Magnetic Resonance Imaging Volumetry of Facial Muscles in Healthy Patients with Facial Palsy  

PubMed Central

Background: Magnetic resonance imaging (MRI) has not yet been established systematically to detect structural muscular changes after facial nerve lesion. The purpose of this pilot study was to investigate quantitative assessment of MRI muscle volume data for facial muscles. Methods: Ten healthy subjects and 5 patients with facial palsy were recruited. Using manual or semiautomatic segmentation of 3T MRI, volume measurements were performed for the frontal, procerus, risorius, corrugator supercilii, orbicularis oculi, nasalis, zygomaticus major, zygomaticus minor, levator labii superioris, orbicularis oris, depressor anguli oris, depressor labii inferioris, and mentalis, as well as for the masseter and temporalis as masticatory muscles for control. Results: All muscles except the frontal (identification in 4/10 volunteers), procerus (4/10), risorius (6/10), and zygomaticus minor (8/10) were identified in all volunteers. Sex or age effects were not seen (all P > 0.05). There was no facial asymmetry with exception of the zygomaticus major (larger on the left side; P = 0.012). The exploratory examination of 5 patients revealed considerably smaller muscle volumes on the palsy side 2 months after facial injury. One patient with chronic palsy showed substantial muscle volume decrease, which also occurred in another patient with incomplete chronic palsy restricted to the involved facial area. Facial nerve reconstruction led to mixed results of decreased but also increased muscle volumes on the palsy side compared with the healthy side. Conclusions: First systematic quantitative MRI volume measures of 5 different clinical presentations of facial paralysis are provided. PMID:25289366

Volk, Gerd F.; Karamyan, Inna; Klingner, Carsten M.; Reichenbach, Jürgen R.

2014-01-01

363

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

364

Diffusion tensor imaging studies on chinese patients with social anxiety disorder.  

PubMed

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

365

Imaging correlates of motor recovery from cerebral infarction and their physiological significance in well-recovered patients  

Microsoft Academic Search

We studied motor representation in well-recovered stroke patients. Eighteen right-handed stroke patients and eleven age-matched control subjects underwent functional Magnetic Resonance Imaging (fMRI) while performing unimanual index finger (abduction–adduction) and wrist movements (flexion–extension) using their recovered and non-affected hand. A subset of these patients underwent Transcranial Magnetic Stimulation (TMS) to elicit motor evoked potentials (MEP) in the first dorsal interosseous

Dinesh G. Nair; Siobhan Hutchinson; Felipe Fregni; Michael Alexander; Alvaro Pascual-Leone; Gottfried Schlaug

2007-01-01

366

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

367

Chronic myeloid leukemia detected on FDG PET/CT imaging in a patient with renal cell carcinoma.  

PubMed

It is well known that hematopoietic cytokine stimulation can cause increased fluorodeoxyglucose (FDG) accumulation in bone marrow on PET/CT imaging, which simulates that seen in patients with bone marrow metastases. However, increased bone marrow FDG uptake can be caused by other etiologies. We report a patient with operated renal cell carcinoma had no history of hematopoietic cytokine stimulation. The FDG PET/CT images showed increased bone marrow FDG uptake, and the patient was diagnosed as chronic myeloid leukemia. This case revealed that increased FDG uptake on bone marrow may be related to neoplastic disease of the hematopoietic tissues. PMID:23177344

Varoglu, E; Kaya, B; Sari, O

2013-01-01

368

A clinical comparison of image quality and patient exposure reduction in panoramic radiography with heavy metal filtration.  

PubMed

Laboratory and clinical studies with the use of rare earth intensifying screens and four different forms of heavy metal elements serving as additional beam filtration were performed for panoramic radiography to identify the most efficacious system. Balanced density images were evaluated for contrast indices, resolution, relative dose reduction, and subjective image quality. Clinical studies were performed with a standard calcium tungstate imaging system and the four most promising experimental imaging systems that showed improvement over the standard system. Dosimetric studies were performed with the use of ionization chambers and thermoluminescent dosimetry (TLD) dosimeters. Exposure reductions of 34% to 79%, depending on the anatomic site and the imaging system used, were achieved. Subjective image quality was evaluated and analyzed statistically. This study concluded that the use of a Kodak Lanex regular screen/T-Mat G film with either Lanex screen or yttrium added beam filtration results in reduced patient exposure in panoramic radiography while image quality is maintained or improved. PMID:2740096

Kapa, S F; Tyndall, D A

1989-06-01

369

Neuro-imaging in Patients Referred to a Neuro-ophthalmology Service: The Rates of Appropriateness and Concordance in Interpretation  

PubMed Central

Objective Neuro-imaging studies are frequently ordered to investigate neuro-ophthalmic symptoms. When misused these studies are expensive and time-consuming. This study aimed to describe the type and frequency of neuro-imaging errors in patients referred to an academic neuro-ophthalmology service and to measure how frequently these neuro-imaging studies were re-interpreted. Design Prospective cohort study Participants 84 consecutive patients referred to an academic neuro-ophthalmology practice Methods From November 2009 through July 2010 we prospectively enrolled 84 consecutive new patients who had received a neuro-imaging study in the last 12 months specifically in evaluation of their presenting neuro-ophthalmic symptoms. Participants then underwent a complete neuro-ophthalmic evaluation followed by a review of prior neuro-imaging. Questions regarding appropriateness of the most recent imaging, concordance of radiological interpretation, and re-evaluation of referring diagnoses were answered by the attending physician. Main Outcome Measures 1. The frequency and types of errors committed in the utilization of neuro-imaging. 2. The frequency of re-interpretation of pre-referral neuro-imaging studies following neuro-ophthalmic history and examination. Results Most study participants (84.5%; 71/84) underwent magnetic resonance imaging (MRI) prior to referral; 15.5% (13/84) underwent only computed tomography (CT). The rate of sub-optimal neuro-imaging studies was 38.1% (32/84). The three most common reasons for sub-optimal studies were incomplete area of imaging (34.4%; 11/32), wrong study type (28.1%; 9/32), and poor image quality (21.9%; 7/32). 24 of 84 subjects (28.6%) required additional neuro-imaging. We agreed with the radiology interpretation of the prior neuro-imaging studies in the majority (77.4%; 65/84) of patients. The most common anatomic locations for discordance in interpretation were the intraorbital optic nerve (35%; 7/20) and the brainstem (20%; 4/20). Conclusions There was a high rate of sub-optimal neuro-imaging studies performed in patients referred to neuro-ophthalmology. These findings have significant implications given the increasing attention to resource utilization currently and in the near future. PMID:22484117

McClelland, Collin; Van Stavern, Gregory P.; Shepherd, J. Banks; Gordon, Mae; Huecker, Julia

2012-01-01

370

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

371

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

372

Cardiac Imaging for Ischemia in Asymptomatic Patients: Use of Coronary Artery Calcium Scanning to Improve Patient Selection: Lessons from the EISNER Study  

Microsoft Academic Search

\\u000a We review emerging data that identify how coronary artery calcium (CAC) scanning can complement radionuclide cardiac stress\\u000a testing for ischemia in the work-up of patients with suspected coronary artery disease (CAD). First, among screening populations,\\u000a i.e., patients with low (<15%) Bayesian likelihood of CAD, stress imaging is characterized by a high false-positive test rate\\u000a for CAD prediction and inability to

Alan Rozanski; Heidi Gransar; Nathan D. Wong; Leslee J. Shaw; Michael J. Zellweger; Daniel S. Berman

373

Clinical outcomes of percutaneous drainage of breast fluid collections following mastectomy with expander-based breast reconstruction  

PubMed Central

PURPOSE To determine clinical outcomes of patients who underwent imaging-guided percutaneous drainage of breast fluid collections following mastectomy and breast reconstruction. MATERIAL AND METHODS Retrospective review included all consecutive patients who underwent percutaneous drainage of fluid collections following mastectomy with tissue expander-based reconstruction between January 2007 and September 2012. A total of 879 mastectomies (563 patients) with expander-based breast reconstruction were performed during this period. 28 patients (5%) developed fluid collections, which led to 30 imaging-guided percutaneous drainage procedures. The median follow up time was 533 days. Patient characteristics, surgical technique, microbiology analysis, and clinical outcomes were reviewed. RESULTS The mean age was 51.5 years (range 30.9 to 69.4 years) and the median time between breast reconstruction and drainage was 35 days (range 4 to 235 days). Erythema and swelling were the most common presenting symptoms. The median volume of fluid evacuated at the time of drain placement was 70 mL. Drains were left in place for a median 14 days (range 6 to 34 days). Microorganisms were detected in the fluid in 12 of 30 drainage procedures, with Staphylococcus aureus being the most common microorganism. No further intervention was needed in 21 of 30 drainage procedures (70%). However, surgical intervention (removal of expanders) was needed following 6 (20%) drainages, and additional percutaneous drainage procedures were performed following 3 (10%) drainages. CONCLUSION Percutaneous drainage is an effective means of treating post operative fluid collections after expander-based breast reconstruction and can obviate the need for repeat surgery in most cases. PMID:23810309

2015-01-01

374

[Skeletal muscle magnetic resonance imaging study in a patient with diabetic lumbosacral radiculoplexus neuropathy].  

PubMed

A 63-year-old man with type 2 diabetes mellitus developed deep aching and numbness in the right hip and lower extremity with rapid body weight loss. Neurological examination revealed weakness of the right hamstrings, tibialis anterior, and peroneus longus muscles with diminished ankle tendon reflex. We diagnosed him with diabetic lumbosacral radicuoloplexus neuropathy (DLRPN) based on neurological, radiological, and neurophysiological findings. Magnetic resonance imaging (MRI) of skeletal muscles showed high intensity signals on T2-weighted images in bilateral hamstrings, adductor magnus and right tensor fasciae latae, and lower leg extensor muscles. The MRI findings suggested muscle edema caused by acute denervation. DLRPN, or diabetic amyotrophy, is known to be caused by ischemic axonal degeneration. Our patient showed good functional recovery, and abnormal MRI signals in the involved muscles mostly disappeared in parallel to the clinical course. Distribution of the denervated muscles suggested that our patient had either patchy lesions in the lumbosacaral plexus or mononeuropathy multiplex in the nerve branches. The current study highlights the potential of skeletal muscle MRI for clinical evaluation of DLRPN. PMID:25283832

Matsuda, Nozomu; Kobayashi, Shunsuke; Ugawa, Yoshikazu

2014-01-01

375

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

376

Imaging the lungs in asthmatic patients by using hyperpolarized helium-3 magnetic resonance: Assessment of response to methacholine and exercise challenge  

Microsoft Academic Search

Background: Imaging of gas distribution in the lungs of patients with asthma has been restricted because of the lack of a suitable gaseous contrast agent. Hyperpolarized helium-3 (HHe3) provides a new technique for magnetic resonance imaging of lung diseases. Objective: We sought to investigate the use of HHe3 gas to image the lungs of patients with moderate or severe asthma

Saba Samee; Talissa Altes; Patrick Powers; Eduard E. de Lange; Jack Knight-Scott; Gary Rakes; John P. Mugler III; Jonathan M. Ciambotti; Bennet A. Alford; James R. Brookeman; Thomas A. E. Platts-Mills

2003-01-01

377

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

378

Feeling unreal: a functional imaging study in patients with Kleine-Levin syndrome.  

PubMed

Kleine-Levin syndrome is characterized by relapsing-remitting episodes of severe hypersomnia, cognitive impairment, apathy, derealization and behavioural disturbances. Between episodes, patients have normal sleep, mood and behaviour. Functional imaging studies performed in small series of patients with Kleine-Levin syndrome with visual or semi-quantitative, uncontrolled analysis yielded equivocal brain changes. Using whole brain voxel-based group analysis, we compared brain perfusion scintigraphy during and between episodes in consecutive patients with Kleine-Levin syndrome versus healthy control subjects and correlated perfusion changes with disease severity and symptoms, focusing on less studied but disabling symptoms, such as apathy and derealization. During asymptomatic periods, 41 patients (mean age of 22.3 ± 8.1 years, 56.1% male) and 15 age- and sex-matched healthy control subjects underwent single-photon emission computed tomography scanning with technetium-99m ethyl cysteinate dimer. Eleven patients repeated the test during a symptomatic period. Compared with controls, patients during asymptomatic periods had persistent hypoperfusion in the hypothalamus, the thalamus (mainly the right posterior part), the caudate nucleus, and cortical associative areas, including the anterior cingulate, (Brodmann area 25), the orbito-frontal (Brodmann area 11) and the right superior temporal cortices (Brodmann area 22), extending to the insula (P < 0.001 in all area). Two additional hypoperfused areas emerged during symptomatic periods (P < 0.001), located in the right dorsomedial prefrontal cortex (Brodmann area 8) and the right parieto-temporal junction (Brodmann areas 22 and 39). These two areas were more affected between episodes, when the mean episode duration was longer (r = -0.53; P < 0.001). The score for the Depersonalization/Derealization Inventory during symptomatic periods strongly correlated with the hypoperfusion of the right (r = -0.74, P < 0.001) and left (r = -0.59, P < 0.005) parieto-temporal junctions. No hyperperfusion was found. Because the parieto-temporal junction (including the angular gyrus) is involved in cross-modal association between somatosensory (body knowledge), auditory and visual information, the robust hypoperfusions and correlations observed in this area may underlie the striking derealization reported by patients during episodes. Defects in the dorsomedial prefrontal cortex may cause apathy. Persistent hypoperfusion in the diencephalic and associative cortical area during asymptomatic periods is a marker of the disease, suggestive of a scenario wherein patients compensate for these deficient circuitries. PMID:24785943

Kas, Aurelie; Lavault, Sophie; Habert, Marie-Odile; Arnulf, Isabelle

2014-07-01

379

Dynamic positron tomographic imaging with nitrogen-13 glutamate in patients with coronary artery disease: Comparison with nitrogen-13 ammonia and fluorine-18 fluorodeoxyglucose imaging  

SciTech Connect

This study was designed to test the usefulness of nitrogen-13 (N-13) glutamate imaging with positron emission tomography in defining myocardial ischemia in humans. Seventeen patients who had undergone coronary arteriography were studied with N-13 glutamate at peak supine exercise using a bicycle ergometer, as well as with the flow tracer N-13 ammonia at peak exercise during a second similar exercise test. Six of the patients also underwent imaging with N-13 glutamate at rest before exercise testing; in the remaining 11 patients imaging with fluorine-18 (F-18) fluorodeoxyglucose was performed to assess glucose metabolism after the second exercise test. Seven patients had classic metabolism-flow mismatches consistent with ischemia (that is, decreased N-13 ammonia uptake in a region with relatively increased F-18 fluorodeoxyglucose uptake). There was no evidence of increased N-13 glutamate uptake in the ischemic mismatched regions in any of these patients. In all 17 patients, the uptake of N-13 glutamate during exercise paralleled the uptake of N-13 ammonia during exercise, suggesting that N-13 glutamate behaves as a flow tracer rather than as a metabolic marker of ischemia in humans.

Krivokapich, J.; Barrio, J.R.; Huang, S.C.; Schelbert, H.R. (Univ. of California, Los Angeles (USA))

1990-11-01

380

Hypovolemia in toxemia of pregnancy: Plasma expander therapy with surveillance of central venous pressure  

Microsoft Academic Search

The influence of plasma expanders on hemodynamics of the placenta, the maternal blood pressure and kidney function was investigated in 20 patients with EPH gestosis. The plasma expanders were administered under surveillance of the central venous pressure (CVP), measured in the superior vena cava. In 18 of the patients, abnormally low values of the CVP similar to those in patients

S. E. Cloeren; T. H. Lippert; M. Hinselmann

1973-01-01

381

Transfer patient imaging: a survey of members of the American Society of Emergency Radiology.  

PubMed

When trauma patients are transferred from outside hospitals, the receiving clinicians often consult their local radiologists for definitive interpretations of outside examinations (IOE). Such requests introduce a host of logistical, medicolegal, and financial concerns related to quality control and resource utilization. We surveyed 701 members of the American Society of Emergency Radiology to elucidate these concerns. We found that the majority of emergency departments still rely on compact disks for conveyance of outside images; hard film and network transfers were minor mechanisms for most respondents. Sixty-nine percent of the respondents indicated that radiologist reports accompany fewer than 25 % of all transferred imaging studies; of the reports that do arrive, most are unverified preliminary reads. There is considerable variability in billing practices and reimbursement patterns for radiologic second opinions; 68 % of the respondents do not know how often their IOEs are reimbursed. Suboptimal communication between community hospitals and referral centers may result in duplicated efforts and inconsistent quality of medical imaging studies. Further investigation into the role of radiology trainees in the handling of outside studies is also highly recommended. PMID:22527362

Robinson, Jeffrey D; McNeeley, Michael F

2012-10-01

382

Three-Dimensional Microwave Breast Imaging: Dispersive Dielectric Properties Estimation using Patient-Specific Basis Functions  

PubMed Central

Breast imaging via microwave tomography involves estimating the distribution of dielectric properties within the patient's breast on a discrete mesh. The number of unknowns in the discrete mesh can be very large for three-dimensional imaging, and this results in computational challenges. We propose a new approach where the discrete mesh is replaced with a relatively small number of smooth basis functions. The dimension of the tomography problem is reduced by estimating the coefficients of the basis functions instead of the dielectric properties at each element in the discrete mesh. The basis functions are constructed using knowledge of the location of the breast surface. The number of functions used in the basis can be varied to balance resolution and computational complexity. The reduced dimension of the inverse problem enables application of a computationally efficient, multiple-frequency inverse scattering algorithm in 3-D. The efficacy of the proposed approach is verified using two 3-D anatomically realistic numerical breast phantoms. It is shown for the case of single-frequency microwave tomography that the imaging accuracy is comparable to that obtained when the original discrete mesh is used, despite the reduction of the dimension of the inverse problem. Results are also shown for a multiple-frequency algorithm where it is computationally challenging to use the original discrete mesh. PMID:19211350

Winters, David W.; Shea, Jacob D.; Kosmas, Panagiotis; Van Veen, Barry D.; Hagness, Susan C.

2009-01-01

383

Smaragdyrins: emeralds of expanded porphyrin family.  

PubMed

Porphyrins are tetrapyrrolic 18 ? electron conjugated macrocycles with wide applications that range from materials to medicine. Expanded porphyrins, synthetic analogues of porphyrins that contain more than 18 ? electrons in the conjugated pathway, have an increased number of pyrroles or other heterocyles or multiple meso-carbon bridges. The expanded porphyrins have attracted tremendous attention because of unique features such as anion binding or transport that are not present in porphyrins. Expanded porphyrins exhibit wide applications that include their use in the coordination of large metal ions, as contrasting agents in magnetic resonance imaging (MRI), as sensitizers for photodynamic therapy (PDT) and as materials for nonlinear optical (NLO) studies. Pentaphyrin 1, sapphyrin 2, and smaragdyrin 3 are expanded porphyrins that include five pyrroles or heterocyclic rings. They differ from each other in the number of bridging carbons and direct bonds that connect the five heterocyclic rings. Sapphyrins were the first stable expanded porphyrins reported in the literature and remain one of the most extensively studied macrocycles. The strategies used to synthesize sapphyrins are well established, and these macrocycles are versatile anion binding agents. They possess rich porphyrin-like coordination chemistry and have been used in diverse applications. This Account reviews developments in smaragdyrin chemistry. Although smaragdyrins were discovered at the same time as sapphyrins, the chemistry of smaragdyrins remained underdeveloped because of synthetic difficulties and their comparative instability. Earlier efforts resulted in the isolation of stable ?-substituted smaragdyrins and meso-aryl isosmaragdyrins. Recently, res