Journal of vascular and interventional radiology : JVIR, 2014
To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequen... more To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequency (RF) ablation of liver metastases, using predefined patterns on contrast-enhanced computed tomography (CT) and positron emission tomography (PET) combined with CT (PET/CT) acquired 24 hours after RF ablation. There were 45 metastases in 20 patients treated. After 24 hours, imaging of the ablation zones was performed with contrast-enhanced PET/CT. Three independent radiologists prospectively assessed contrast-enhanced CT and combined PET/CT images to identify three patterns: pattern I, no tissue enhancement or fluorodeoxyglucose uptake between the ablation zone and the liver parenchyma; pattern II, a rimlike pattern; and pattern III, a peripheral nodule. PET/CT images obtained after 8-10 weeks were evaluated for LTP. The patterns were analyzed for their sensitivity, specificity, positive predictive value, and negative predictive value for predicting LTP. Pattern I was most frequently o...
PURPOSE/AIM The purpose of this exhibit is: 1. To demonstrate typical artifacts and clinical pitf... more PURPOSE/AIM The purpose of this exhibit is: 1. To demonstrate typical artifacts and clinical pitfalls related uniquely to MR-PET 2. To review the technical principles of MR-PET, as a basis to understand artifacts and pitfalls 3. To revise MR-based attenuation correction methods, as a source for artifacts and pitfalls unique to MR-PET as compared to PET-CT CONTENT ORGANIZATION Imaging artifacts and their implication on clinical assessment Metal artifacts related to implants and medical devices Truncation artifacts Respiratory and motion artifacts and their impact on lesion detection Technical principles, design and operation of combined MR- PET scanners Inbuilt and in-line solutions of MR-PET scanner design Hardware and software adjustments Principles of MR based attenuation correction: MR attenuation correction sequences (3D T1 weighted GRE; UTE) Model based segmentation; 3-segment model SUMMARY The major teaching points of this exhibit are: The specific technical design of MR-PET s...
The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emph... more The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emphasis is placed on the appearances following intravenous administration of both non-specific and liver-specific MR contrast agents. On post-gadolinium gradient-echo (GE) images an early, intense, and peripheral enhancement was followed by a homogeneous, complete, and persistent enhancement. Lesions showed no uptake following administration of ferumoxides particles nor mangafodipir trisodium, respectively. During follow-up, a peripheral hyperintense rim appeared on precontrast T1-weighted images, a feature not previously described.
Rationale and ObjectivesPatients with cancer who are referred to a dedicated oncology center usua... more Rationale and ObjectivesPatients with cancer who are referred to a dedicated oncology center usually have undergone previous imaging studies that the oncologists typically desire to have reviewed by radiologists. Such reinterpretations can be complex and time-consuming, yet many institutions do not systematically account for them as part of the total workload. The purpose of this study was to ascertain the
The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emph... more The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emphasis is placed on the appearances following intravenous administration of both non-specific and liver-specific MR contrast agents. On post-gadolinium gradient-echo (GE) images an early, intense, and peripheral enhancement was followed by a homogeneous, complete, and persistent enhancement. Lesions showed no uptake following administration of ferumoxides particles nor mangafodipir trisodium, respectively. During follow-up, a peripheral hyperintense rim appeared on precontrast T1-weighted images, a feature not previously described.
LEARNING OBJECTIVES 1) Understand the need to offer incentive compensation (bonus) to faculty in ... more LEARNING OBJECTIVES 1) Understand the need to offer incentive compensation (bonus) to faculty in Academic Radiology Departments. 2) To be able to describe the advantages and disadvantages of productivity only incentive plans in Academic Radiology. 3)Understand methods of providing incentives other than clinical productivity. 4) Understand how to insure fairness and a feeling of working as a team with incentive-based compensation plans. 5) Understand how incentive systems used by private practices are different from that of an Academic Radiology Department. (This course is part of the Leadership Track)
... P. Ros a , J. Corral b , V. Roldán c , F. Marín d , V. Vicente a and R. González-Conejero b ,... more ... P. Ros a , J. Corral b , V. Roldán c , F. Marín d , V. Vicente a and R. González-Conejero b , Corresponding Author ... 55 patients with spontaneous intracranial hemorrhage (SIH), 206 with deep venous thrombosis (DVT) and 281 with premature myocardial infarction (AMI < 45). ...
ABSTRACT The spleen can be either primarily or secondarily involved with neoplasia. However, comp... more ABSTRACT The spleen can be either primarily or secondarily involved with neoplasia. However, compared with other abdominal organs, primary tumoral anomalies of the spleen are relatively uncommon. Both benign and malignant primary neoplastic involvement of the spleen have been described, although the malignant causes are considered to be more frequent, with lymphoma being the most common primary splenic malignant tumor (Taylor et al. 1991). Of nonlymphoid primary neoplastic lesions, those of vascular origin constitute the majority, with hemangiomas and angiosarcomas being the tumors most frequently encountered (Ferrozzi et al. 1996). Other, more uncommon primary lesions encountered in the spleen include benign entities, such as cyst, lymphangioma, hamartoma and, less commonly, lesions with variable biologic behavior, such as hemangiopericytoma, epithelioid vascular tumor and littoral cell angioma. Far more commonly, however, the spleen will be secondarily involved by metastatic disease.
JBR-BTR: organe de la Société royale belge de radiologie (SRBR) = orgaan van de Koninklijke Belgische Vereniging voor Radiologie (KBVR)
Immunosuppression for therapeutic reasons (e.g. post transplantation, post chemotherapy), as well... more Immunosuppression for therapeutic reasons (e.g. post transplantation, post chemotherapy), as well as pathologic immunodeficiency due to certain pathologic conditions (e.g. AIDS, leukemia), is increasingly encountered in daily medical practice. As a result, the concomitant risk for opportunistic infections is higher and immunocompromised patients may present with uncommon clinical and radiologic conditions. We report on a case of a 33-year-old immunocompromised woman with a history of recurrent T-cell lymphoblastic lymphoma, which presented with abdominal pain. Computed tomography (CT) images demonstrated significant small bowel dilatation, wall thickening, and high-density intestinal content, with a focal point of transition in the pelvis. Extensive fungal enteritis due to Candida Albicans with partial small bowel obstruction was found on autopsy.
PURPOSE/AIM MR/PET is a hybrid imaging technology which was recently introduced in the clinical a... more PURPOSE/AIM MR/PET is a hybrid imaging technology which was recently introduced in the clinical arena. The MR component has a high soft-tissue contrast and reveals biological information when performing functional sequences like diffusion-weighted imaging (DWI). The PET component enables to visualize metabolism with a high sensitivity. The aim of this educational exhibit is to compare MR/PET vs. PET/CT for rectal cancer staging and to demonstrate MR/PET as a one stop approach for this clinical indication. CONTENT ORGANIZATION Current standard for rectal cancer staging: T staging with MRI. N and M staging with PET/CT MR/PET in rectal cancer staging for T, N and M staging as one stop approach Role of DWI for discordant cases when comparing MR/PET vs. PET/CT SUMMARY MR/PET is feasible and promising in rectal cancer patients. Originally proper staging in rectal cancer required two different imaging techniques, namely MRI and PET/CT. MR/PET offers an evolving one stop solution for stagin...
PURPOSE/AIM To illustrate the imaging appearance of a variety of pancreatic pathologies using PET... more PURPOSE/AIM To illustrate the imaging appearance of a variety of pancreatic pathologies using PET/MRI as a new hybrid imaging modality To outline the advantages and potential value of PET/MRI in pancreatic imaging CONTENT ORGANIZATION Current role and diagnostic value of PET (/CT) and MRI in the diagnosis of pancreatic pathology Specific technology key features of PET/MRI Scanner design MR based attenuation correction and 3-segment model attenuation map Sequential image acquisition with state-of-the-art Time of Flight PET technology and 3Tesla MRI Propose and discuss an appropriate integrated imaging protocol/workflow for PET/MRI in pancreatic pathology Whole body attenuation correction and anatomic reference Organ specific protocols for pancreas and liver Whole body PET Pictorial review of a variety of benign and malignant pancreatic To discuss the potential benefits and incremental value of PET/MRI in pancreatic imaging over current standard of care imaging protocols SUMMARY Teach...
PET/MR is a new imaging modality which is currently being evaluated for research and clinical pur... more PET/MR is a new imaging modality which is currently being evaluated for research and clinical purposes. The necessary space requirements, the implementation of MR safety zone restrictions and controls, and the benefits of the system for anatomical localization are discussed. Appropriate staffing is of critical importance, as Nuclear Medicine technologists supporting the PET/MR need to be trained in the MRI magnet environment and MR specific patient screening, while MRI technologists require training in radiation safety. A close collaboration between nuclear medicine and radiology physicians is critical to maximize the benefit from the PET/MR in the clinical setting. This collaboration must address protocols used for clinical cases as well as reporting. For research purposes, an appropriate funding infrastructure needs to be in place to operate and maintain the system.
We report on a 58-year-old man with known diabetes, congestive heart failure, and need for chroni... more We report on a 58-year-old man with known diabetes, congestive heart failure, and need for chronic hemodialysis presenting with right lower abdominal quadrant pain, fever, and leukocytosis. Although initial clinical findings were highly suggestive of acute appendicitis, CT revealed marked circumferential wall thickening of the cecum, which was interpreted as cecal infarction by the radiologist. Intraoperatively, cecal necrosis was confirmed, but the ileocecal valve and, especially, the appendix showed no ischemia. No vascular occlusions were found. Histopathologic analysis of the resected cecum demonstrated isolated transmural cecal necrosis with marked infiltration of the cecal wall by numerous bacteria and neutrophils. We present the CT features and histopathologic findings of isolated cecal gangrene, review the pathogenesis of occlusive and nonocclusive cecal ischemia or infarction, and discuss the role of bacterial superinfection as a potential cofactor in the pathogenesis of is...
This study identifies the major sources of overhead fees/costs and subsidies in academic radiolog... more This study identifies the major sources of overhead fees/costs and subsidies in academic radiology departments (ARDs) in the US and determines the differences between them based on geographic location or the size of their affiliated hospital. ARDs in the Northeast had the highest level of financial support from their affiliated hospitals when compared to those in the South/Southwest; however, a greater number of Midwest ARDs receive high levels of funding for teaching from their medical schools when compared to the northeast. Significantly fewer ARDs affiliated with hospitals of less than 200 beds receive subsidies for their activities when compared to those affiliated with larger hospitals. Differences in levels of overhead costs/ subsidies available to ARDs are associated with either geographic location or the size of the affiliated hospital. The reasons for these differences may be related to a variety of legal, contractual, or fiscal factors. Investigation of existing geographic...
World journal of gastrointestinal oncology, Jan 15, 2013
Pneumo-computed tomography (PnCT) is a technique primarily developed and used to study stenotic l... more Pneumo-computed tomography (PnCT) is a technique primarily developed and used to study stenotic lesions of the esophagus, gastroesophageal junction and stomach for pre-surgical planning. It helps to define both upper and lower borders of neoplasms located in the aforementioned areas. It achieves maximum lumen distension with CO2 highlighting thickened areas of the esophageal wall, thus allowing an accurate quantification of their extents. Although there are other alternatives for distension (oral contrast agents, water and effervescent granules), they may be suboptimal. Patients with locally advanced esophageal cancer have a dismal prognosis despite surgical resection. Therefore, neoadjuvant treatment strategies using radiation therapy and chemotherapy were developed to improve survival. Neoadjuvant therapy improves esophageal tumor prognosis in a substantial proportion of patients, and the use of imaging techniques is mandatory to detect their response. PnCT combined with virtual e...
International journal of clinical and experimental medicine, 2014
PET/MRI is an evolving hybrid imaging modality which combines the inherent strengths of MRIs soft... more 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.
American journal of nuclear medicine and molecular imaging, 2014
Positron emission tomography/magnetic resonance imaging (PET/MRI) leverages the high soft-tissue ... more Positron emission tomography/magnetic resonance imaging (PET/MRI) leverages the high soft-tissue contrast and the functional sequences of MR with the molecular information of PET in one single, hybrid imaging technology. This technology, which was recently introduced into the clinical arena in a few medical centers worldwide, provides information about tumor biology and microenvironment. Studies on indirect PET/MRI (use of positron emission tomography/computed tomography (PET/CT) images software fused with MRI images) have already generated interesting preliminary data to pave the ground for potential applications of PET/MRI. These initial data convey that PET/MRI is promising in neuro-oncology and head & neck cancer applications as well as neoplasms in the abdomen and pelvis. The pediatric and young adult oncology population requiring frequent follow-up studies as well as pregnant woman might benefit from PET/MRI due to its lower ionizing radiation dose. The indication and planning...
Journal of vascular and interventional radiology : JVIR, 2014
To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequen... more To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequency (RF) ablation of liver metastases, using predefined patterns on contrast-enhanced computed tomography (CT) and positron emission tomography (PET) combined with CT (PET/CT) acquired 24 hours after RF ablation. There were 45 metastases in 20 patients treated. After 24 hours, imaging of the ablation zones was performed with contrast-enhanced PET/CT. Three independent radiologists prospectively assessed contrast-enhanced CT and combined PET/CT images to identify three patterns: pattern I, no tissue enhancement or fluorodeoxyglucose uptake between the ablation zone and the liver parenchyma; pattern II, a rimlike pattern; and pattern III, a peripheral nodule. PET/CT images obtained after 8-10 weeks were evaluated for LTP. The patterns were analyzed for their sensitivity, specificity, positive predictive value, and negative predictive value for predicting LTP. Pattern I was most frequently o...
Journal of vascular and interventional radiology : JVIR, 2014
To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequen... more To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequency (RF) ablation of liver metastases, using predefined patterns on contrast-enhanced computed tomography (CT) and positron emission tomography (PET) combined with CT (PET/CT) acquired 24 hours after RF ablation. There were 45 metastases in 20 patients treated. After 24 hours, imaging of the ablation zones was performed with contrast-enhanced PET/CT. Three independent radiologists prospectively assessed contrast-enhanced CT and combined PET/CT images to identify three patterns: pattern I, no tissue enhancement or fluorodeoxyglucose uptake between the ablation zone and the liver parenchyma; pattern II, a rimlike pattern; and pattern III, a peripheral nodule. PET/CT images obtained after 8-10 weeks were evaluated for LTP. The patterns were analyzed for their sensitivity, specificity, positive predictive value, and negative predictive value for predicting LTP. Pattern I was most frequently o...
PURPOSE/AIM The purpose of this exhibit is: 1. To demonstrate typical artifacts and clinical pitf... more PURPOSE/AIM The purpose of this exhibit is: 1. To demonstrate typical artifacts and clinical pitfalls related uniquely to MR-PET 2. To review the technical principles of MR-PET, as a basis to understand artifacts and pitfalls 3. To revise MR-based attenuation correction methods, as a source for artifacts and pitfalls unique to MR-PET as compared to PET-CT CONTENT ORGANIZATION Imaging artifacts and their implication on clinical assessment Metal artifacts related to implants and medical devices Truncation artifacts Respiratory and motion artifacts and their impact on lesion detection Technical principles, design and operation of combined MR- PET scanners Inbuilt and in-line solutions of MR-PET scanner design Hardware and software adjustments Principles of MR based attenuation correction: MR attenuation correction sequences (3D T1 weighted GRE; UTE) Model based segmentation; 3-segment model SUMMARY The major teaching points of this exhibit are: The specific technical design of MR-PET s...
The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emph... more The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emphasis is placed on the appearances following intravenous administration of both non-specific and liver-specific MR contrast agents. On post-gadolinium gradient-echo (GE) images an early, intense, and peripheral enhancement was followed by a homogeneous, complete, and persistent enhancement. Lesions showed no uptake following administration of ferumoxides particles nor mangafodipir trisodium, respectively. During follow-up, a peripheral hyperintense rim appeared on precontrast T1-weighted images, a feature not previously described.
Rationale and ObjectivesPatients with cancer who are referred to a dedicated oncology center usua... more Rationale and ObjectivesPatients with cancer who are referred to a dedicated oncology center usually have undergone previous imaging studies that the oncologists typically desire to have reviewed by radiologists. Such reinterpretations can be complex and time-consuming, yet many institutions do not systematically account for them as part of the total workload. The purpose of this study was to ascertain the
The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emph... more The MRI characteristics of a multifocal inflammatory pseudotumor of the liver are described. Emphasis is placed on the appearances following intravenous administration of both non-specific and liver-specific MR contrast agents. On post-gadolinium gradient-echo (GE) images an early, intense, and peripheral enhancement was followed by a homogeneous, complete, and persistent enhancement. Lesions showed no uptake following administration of ferumoxides particles nor mangafodipir trisodium, respectively. During follow-up, a peripheral hyperintense rim appeared on precontrast T1-weighted images, a feature not previously described.
LEARNING OBJECTIVES 1) Understand the need to offer incentive compensation (bonus) to faculty in ... more LEARNING OBJECTIVES 1) Understand the need to offer incentive compensation (bonus) to faculty in Academic Radiology Departments. 2) To be able to describe the advantages and disadvantages of productivity only incentive plans in Academic Radiology. 3)Understand methods of providing incentives other than clinical productivity. 4) Understand how to insure fairness and a feeling of working as a team with incentive-based compensation plans. 5) Understand how incentive systems used by private practices are different from that of an Academic Radiology Department. (This course is part of the Leadership Track)
... P. Ros a , J. Corral b , V. Roldán c , F. Marín d , V. Vicente a and R. González-Conejero b ,... more ... P. Ros a , J. Corral b , V. Roldán c , F. Marín d , V. Vicente a and R. González-Conejero b , Corresponding Author ... 55 patients with spontaneous intracranial hemorrhage (SIH), 206 with deep venous thrombosis (DVT) and 281 with premature myocardial infarction (AMI < 45). ...
ABSTRACT The spleen can be either primarily or secondarily involved with neoplasia. However, comp... more ABSTRACT The spleen can be either primarily or secondarily involved with neoplasia. However, compared with other abdominal organs, primary tumoral anomalies of the spleen are relatively uncommon. Both benign and malignant primary neoplastic involvement of the spleen have been described, although the malignant causes are considered to be more frequent, with lymphoma being the most common primary splenic malignant tumor (Taylor et al. 1991). Of nonlymphoid primary neoplastic lesions, those of vascular origin constitute the majority, with hemangiomas and angiosarcomas being the tumors most frequently encountered (Ferrozzi et al. 1996). Other, more uncommon primary lesions encountered in the spleen include benign entities, such as cyst, lymphangioma, hamartoma and, less commonly, lesions with variable biologic behavior, such as hemangiopericytoma, epithelioid vascular tumor and littoral cell angioma. Far more commonly, however, the spleen will be secondarily involved by metastatic disease.
JBR-BTR: organe de la Société royale belge de radiologie (SRBR) = orgaan van de Koninklijke Belgische Vereniging voor Radiologie (KBVR)
Immunosuppression for therapeutic reasons (e.g. post transplantation, post chemotherapy), as well... more Immunosuppression for therapeutic reasons (e.g. post transplantation, post chemotherapy), as well as pathologic immunodeficiency due to certain pathologic conditions (e.g. AIDS, leukemia), is increasingly encountered in daily medical practice. As a result, the concomitant risk for opportunistic infections is higher and immunocompromised patients may present with uncommon clinical and radiologic conditions. We report on a case of a 33-year-old immunocompromised woman with a history of recurrent T-cell lymphoblastic lymphoma, which presented with abdominal pain. Computed tomography (CT) images demonstrated significant small bowel dilatation, wall thickening, and high-density intestinal content, with a focal point of transition in the pelvis. Extensive fungal enteritis due to Candida Albicans with partial small bowel obstruction was found on autopsy.
PURPOSE/AIM MR/PET is a hybrid imaging technology which was recently introduced in the clinical a... more PURPOSE/AIM MR/PET is a hybrid imaging technology which was recently introduced in the clinical arena. The MR component has a high soft-tissue contrast and reveals biological information when performing functional sequences like diffusion-weighted imaging (DWI). The PET component enables to visualize metabolism with a high sensitivity. The aim of this educational exhibit is to compare MR/PET vs. PET/CT for rectal cancer staging and to demonstrate MR/PET as a one stop approach for this clinical indication. CONTENT ORGANIZATION Current standard for rectal cancer staging: T staging with MRI. N and M staging with PET/CT MR/PET in rectal cancer staging for T, N and M staging as one stop approach Role of DWI for discordant cases when comparing MR/PET vs. PET/CT SUMMARY MR/PET is feasible and promising in rectal cancer patients. Originally proper staging in rectal cancer required two different imaging techniques, namely MRI and PET/CT. MR/PET offers an evolving one stop solution for stagin...
PURPOSE/AIM To illustrate the imaging appearance of a variety of pancreatic pathologies using PET... more PURPOSE/AIM To illustrate the imaging appearance of a variety of pancreatic pathologies using PET/MRI as a new hybrid imaging modality To outline the advantages and potential value of PET/MRI in pancreatic imaging CONTENT ORGANIZATION Current role and diagnostic value of PET (/CT) and MRI in the diagnosis of pancreatic pathology Specific technology key features of PET/MRI Scanner design MR based attenuation correction and 3-segment model attenuation map Sequential image acquisition with state-of-the-art Time of Flight PET technology and 3Tesla MRI Propose and discuss an appropriate integrated imaging protocol/workflow for PET/MRI in pancreatic pathology Whole body attenuation correction and anatomic reference Organ specific protocols for pancreas and liver Whole body PET Pictorial review of a variety of benign and malignant pancreatic To discuss the potential benefits and incremental value of PET/MRI in pancreatic imaging over current standard of care imaging protocols SUMMARY Teach...
PET/MR is a new imaging modality which is currently being evaluated for research and clinical pur... more PET/MR is a new imaging modality which is currently being evaluated for research and clinical purposes. The necessary space requirements, the implementation of MR safety zone restrictions and controls, and the benefits of the system for anatomical localization are discussed. Appropriate staffing is of critical importance, as Nuclear Medicine technologists supporting the PET/MR need to be trained in the MRI magnet environment and MR specific patient screening, while MRI technologists require training in radiation safety. A close collaboration between nuclear medicine and radiology physicians is critical to maximize the benefit from the PET/MR in the clinical setting. This collaboration must address protocols used for clinical cases as well as reporting. For research purposes, an appropriate funding infrastructure needs to be in place to operate and maintain the system.
We report on a 58-year-old man with known diabetes, congestive heart failure, and need for chroni... more We report on a 58-year-old man with known diabetes, congestive heart failure, and need for chronic hemodialysis presenting with right lower abdominal quadrant pain, fever, and leukocytosis. Although initial clinical findings were highly suggestive of acute appendicitis, CT revealed marked circumferential wall thickening of the cecum, which was interpreted as cecal infarction by the radiologist. Intraoperatively, cecal necrosis was confirmed, but the ileocecal valve and, especially, the appendix showed no ischemia. No vascular occlusions were found. Histopathologic analysis of the resected cecum demonstrated isolated transmural cecal necrosis with marked infiltration of the cecal wall by numerous bacteria and neutrophils. We present the CT features and histopathologic findings of isolated cecal gangrene, review the pathogenesis of occlusive and nonocclusive cecal ischemia or infarction, and discuss the role of bacterial superinfection as a potential cofactor in the pathogenesis of is...
This study identifies the major sources of overhead fees/costs and subsidies in academic radiolog... more This study identifies the major sources of overhead fees/costs and subsidies in academic radiology departments (ARDs) in the US and determines the differences between them based on geographic location or the size of their affiliated hospital. ARDs in the Northeast had the highest level of financial support from their affiliated hospitals when compared to those in the South/Southwest; however, a greater number of Midwest ARDs receive high levels of funding for teaching from their medical schools when compared to the northeast. Significantly fewer ARDs affiliated with hospitals of less than 200 beds receive subsidies for their activities when compared to those affiliated with larger hospitals. Differences in levels of overhead costs/ subsidies available to ARDs are associated with either geographic location or the size of the affiliated hospital. The reasons for these differences may be related to a variety of legal, contractual, or fiscal factors. Investigation of existing geographic...
World journal of gastrointestinal oncology, Jan 15, 2013
Pneumo-computed tomography (PnCT) is a technique primarily developed and used to study stenotic l... more Pneumo-computed tomography (PnCT) is a technique primarily developed and used to study stenotic lesions of the esophagus, gastroesophageal junction and stomach for pre-surgical planning. It helps to define both upper and lower borders of neoplasms located in the aforementioned areas. It achieves maximum lumen distension with CO2 highlighting thickened areas of the esophageal wall, thus allowing an accurate quantification of their extents. Although there are other alternatives for distension (oral contrast agents, water and effervescent granules), they may be suboptimal. Patients with locally advanced esophageal cancer have a dismal prognosis despite surgical resection. Therefore, neoadjuvant treatment strategies using radiation therapy and chemotherapy were developed to improve survival. Neoadjuvant therapy improves esophageal tumor prognosis in a substantial proportion of patients, and the use of imaging techniques is mandatory to detect their response. PnCT combined with virtual e...
International journal of clinical and experimental medicine, 2014
PET/MRI is an evolving hybrid imaging modality which combines the inherent strengths of MRIs soft... more 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.
American journal of nuclear medicine and molecular imaging, 2014
Positron emission tomography/magnetic resonance imaging (PET/MRI) leverages the high soft-tissue ... more Positron emission tomography/magnetic resonance imaging (PET/MRI) leverages the high soft-tissue contrast and the functional sequences of MR with the molecular information of PET in one single, hybrid imaging technology. This technology, which was recently introduced into the clinical arena in a few medical centers worldwide, provides information about tumor biology and microenvironment. Studies on indirect PET/MRI (use of positron emission tomography/computed tomography (PET/CT) images software fused with MRI images) have already generated interesting preliminary data to pave the ground for potential applications of PET/MRI. These initial data convey that PET/MRI is promising in neuro-oncology and head & neck cancer applications as well as neoplasms in the abdomen and pelvis. The pediatric and young adult oncology population requiring frequent follow-up studies as well as pregnant woman might benefit from PET/MRI due to its lower ionizing radiation dose. The indication and planning...
Journal of vascular and interventional radiology : JVIR, 2014
To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequen... more To assess a classification scheme for predicting local tumor progression (LTP) after radiofrequency (RF) ablation of liver metastases, using predefined patterns on contrast-enhanced computed tomography (CT) and positron emission tomography (PET) combined with CT (PET/CT) acquired 24 hours after RF ablation. There were 45 metastases in 20 patients treated. After 24 hours, imaging of the ablation zones was performed with contrast-enhanced PET/CT. Three independent radiologists prospectively assessed contrast-enhanced CT and combined PET/CT images to identify three patterns: pattern I, no tissue enhancement or fluorodeoxyglucose uptake between the ablation zone and the liver parenchyma; pattern II, a rimlike pattern; and pattern III, a peripheral nodule. PET/CT images obtained after 8-10 weeks were evaluated for LTP. The patterns were analyzed for their sensitivity, specificity, positive predictive value, and negative predictive value for predicting LTP. Pattern I was most frequently o...
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Papers by Pablo Ros