David M. Hough

Prospective Comparison of State-of-the-Art MR Enterography and CT Enterography in Small-Bowel Crohn's Disease

OBJECTIVE The objective of our study was to prospectively obtain pilot data on the accuracy of MR enterography for detecting small-bowel Crohns disease compared with CT enterography and with a clinical reference standard based on imaging, clinical information, and ileocolonoscopy. SUBJECTS AND METHODS The study group for this blinded prospective study was composed of 33 patients with suspected active Crohns ileal inflammation who were scheduled for clinical CT enterography and ileocolonoscopy and had consented to also undergo MR enterography. The MR enterography and CT enterography examinations were each interpreted by two radiologists with disagreements resolved by consensus. The reports from ileocolonoscopy with or without mucosal biopsy were interpreted by a gastroenterologist. The reference standard for the presence of small-bowel Crohns disease was based on the final clinical diagnosis by the referring gastroenterologist after reviewing all of the available information. RESULTS All 33 patients underwent CT enterography and ileocolonoscopy, 30 of whom also underwent MR enterography. The sensitivities of MR enterography and CT enterography for detecting active small-bowel Crohns disease were similar (90.5% vs 95.2%, respectively; p = 0.32). The image quality scores for MR enterography examinations were significantly lower than those for CT enterography (p = 0.005). MR enterography and CT enterography identified eight cases (24%) with a final diagnosis of active small-bowel inflammation in which the ileal mucosa appeared normal at ileocolonoscopy. Furthermore, enterography provided the only available imaging in three additional patients who did not have ileal intubation. CONCLUSION MR enterography and CT enterography have similar sensitivities for detecting active small-bowel inflammation, but image quality across the study cohort was better with CT. Cross-sectional enterography provides complementary information to ileocolonoscopy.

Dual-Energy and Dual-Source CT: Is There a Role in the Abdomen and Pelvis?

Dual-energy CT refers to the use of CT data representing two different energy spectra and allows for the possibility of differentiating and classifying tissue to obtain material-specific images. Dual-energy CT data can be acquired using various CT hardware platforms, with numerous approaches also existing for display of anatomic and material-specific dual-energy information. Dual-source CT refers to the use of two x-ray sources and two x-ray detectors mounted on a single CT gantry and can be used in either a dual-energy or single-energy mode. This article summarizes and reviews current and potential applications for dual-energy and dual-source CT in the abdomen and pelvis.

Pancreatic ductal adenocarcinoma radiology reporting template: Consensus statement of the society of abdominal radiology and the american pancreatic association

Pancreatic ductal adenocarcinoma is an aggressive malignancy with a high mortality rate. Proper determination of the extent of disease on imaging studies at the time of staging is one of the most important steps in optimal patient management. Given the variability in expertise and definition of disease extent among different practitioners as well as frequent lack of complete reporting of pertinent imaging findings at radiologic examinations, adoption of a standardized template for radiology reporting, using universally accepted and agreed on terminology for solid pancreatic neoplasms, is needed. A consensus statement describing a standardized reporting template authored by a multi-institutional group of experts in pancreatic ductal adenocarcinoma that included radiologists, gastroenterologists, and hepatopancreatobiliary surgeons was developed under the joint sponsorship of the Society of Abdominal Radiologists and the American Pancreatic Association. Adoption of this standardized imaging reporting template should improve the decision-making process for the management of patients with pancreatic ductal adenocarcinoma by providing a complete, pertinent, and accurate reporting of disease staging to optimize treatment recommendations that can be offered to the patient. Standardization can also help to facilitate research and clinical trial design by using appropriate and consistent staging by means of resectability status, thus allowing for comparison of results among different institutions.

Appropriate Patient Selection at Abdominal Dual-Energy CT Using 80 kV: Relationship between Patient Size, Image Noise, and Image Quality

PURPOSE To determine the computed tomographic (CT) detector configuration, patient size, and image noise limitations that will result in acceptable image quality of 80-kV images obtained at abdominal dual-energy CT. MATERIALS AND METHODS The Institutional Review Board approved this HIPAA-compliant retrospective study from archival material from patients consenting to the use of medical records for research purposes. A retrospective review of contrast material-enhanced abdominal dual-energy CT scans in 116 consecutive patients was performed. Three gastrointestinal radiologists noted detector configuration and graded image quality and artifacts at specified levels-midliver, midpancreas, midkidneys, and terminal ileum-by using two five-point scales. In addition, an organ-specific enhancement-to-noise ratio and background noise were measured in each patient. Patient size was measured by using the longest linear dimension at the level of interest, weight, lean body weight, body mass index, and body surface area. Detector configuration, patient sizes, and image noise levels that resulted in unacceptable image quality and artifact rankings (score of 4 or higher) were determined by using multivariate logistic regression. RESULTS A 14 × 1.2-mm detector configuration resulted in fewer images with unacceptable quality than did the 64 × 0.6-mm configuration at all anatomic levels (P = .004, .01, and .02 for liver, pancreas, and kidneys, respectively). Image acceptability for the kidneys and ileum was significantly greater than that for the liver for all readers and detector configurations (P < .001). For the 14 × 1.2-mm detector configuration, patient longest linear dimensions yielding acceptable image quality across readers ranged from 34.9 to 35.8 cm at the four anatomic levels. CONCLUSION An 80-kV abdominal CT can be performed with appropriate diagnostic quality in a substantial percentage of the population, but it is not recommended beyond the described patient size for each anatomic level. The 14 × 1.2-mm detector configuration should be preferred.

Anatomical basis of chronic pelvic pain syndrome: the ischial spine and pudendal nerve entrapment

Chronic pelvic pain syndrome is a conundrum that may be explained partly by pudendal nerve entrapment (PNE), which causes neuropathic pain. In men with PNE, aberrant development and subsequent malpositioning of the ischial spine appear to be associated with athletic activities during their youth. The changes occur during the period of development and ossification of the spinous process of the ischium.

Dual-phase CT of autoimmune pancreatitis: a multireader study.

OBJECTIVE The purpose of this study was to identify findings that aid in differentiating autoimmune pancreatitis from pancreatic carcinoma using dual-phase CT. MATERIALS AND METHODS Dual-phase CT scans of 74 patients (25 with autoimmune pancreatitis, 33 with pancreatic carcinoma, and 16 with a normal pancreas) were independently evaluated by three radiologists for enhancement of the pancreas; the presence of a capsule-like rim, peripancreatic strands, and pancreatic calcifications; pancreatic duct or bile duct changes; and renal involvement. The frequency of CT characteristics was compared between autoimmune pancreatitis and carcinoma. Interobserver agreement for the three reviewers for the assessment of CT characteristics was evaluated using kappa statistics. RESULTS Diffusely decreased enhancement of the pancreas (autoimmune pancreatitis vs carcinoma: 28% vs 3%; p = 0.02, kappa = 0.33-0.75), capsule-like rim (40% vs 9%; p = 0.009, kappa = 0.42-0.66), peripancreatic strands (60% vs 27%; p = 0.02, kappa = 0.45-0.54), pancreatic calcifications (32% vs 9%; p = 0.04, kappa = 0.14-0.47), bile duct wall enhancement (52% vs 6%; p = 0.0001, kappa = 0.28-0.47), and renal involvement (28% vs 0%; p = 0.002, kappa = 0.32-0.74) were more frequent in patients with autoimmune pancreatitis. Pancreatic duct dilation (24% vs 67%; p = 0.001, kappa = 0.65-0.73) and abrupt cutoff (16% vs 55%; p = 0.003, kappa = 0.60-0.65) were more frequent in patients with carcinoma. CONCLUSION Diffusely decreased enhancement of the pancreas, a capsule-like rim, bile duct enhancement, and renal involvement are useful signs of autoimmune pancreatitis.

Autoimmune pancreatitis: pancreatic and extrapancreatic imaging findings.

OBJECTIVE The purpose of this article is to discuss the systemic nature of autoimmune pancreatitis and its various pancreatic and extrapancreatic imaging findings. CONCLUSION Autoimmune pancreatitis is a systemic disease with a wide range of pancreatic and extrapancreatic imaging findings. These findings can mimic those of other diseases in the pancreas or other organs and therefore are commonly misdiagnosed and mistreated. It is important for radiologists to understand both the pancreatic and extrapancreatic imaging findings of autoimmune pancreatitis to make accurate and timely diagnoses.

Pancreatic Ductal Adenocarcinoma Radiology Reporting Template: Consensus Statement of the Society of Abdominal Radiology and the American Pancreatic Association

Pancreatic ductal adenocarcinoma is an aggressive malignancy with a high mortality rate. Proper determination of the extent of disease on imaging studies at the time of staging is one of the most important steps in optimal patient management. Given the variability in expertise and definition of disease extent among different practitioners as well as frequent lack of complete reporting of pertinent imaging findings at radiologic examinations, adoption of a standardized template for radiology reporting, using universally accepted and agreed on terminology for solid pancreatic neoplasms, is needed. A consensus statement describing a standardized reporting template authored by a multi-institutional group of experts in pancreatic ductal adenocarcinoma that included radiologists, gastroenterologists, and hepatopancreatobiliary surgeons was developed under the joint sponsorship of the Society of Abdominal Radiologists and the American Pancreatic Association. Adoption of this standardized imaging reporting template should improve the decision-making process for the management of patients with pancreatic ductal adenocarcinoma by providing a complete, pertinent, and accurate reporting of disease staging to optimize treatment recommendations that can be offered to the patient. Standardization can also help to facilitate research and clinical trial design by using appropriate and consistent staging by means of resectability status, thus allowing for comparison of results among different institutions.

Autoimmune Pancreatitis: Differentiation From Pancreatic Carcinoma and Normal Pancreas on the Basis of Enhancement Characteristics at Dual-Phase CT

OBJECTIVE The purposes of this study were to define the pancreatic enhancement of autoimmune pancreatitis at dual-phase CT and to compare it with that of pancreatic carcinoma and a normal pancreas. MATERIALS AND METHODS Dual-phase CT scans of 101 patients (43 with autoimmune pancreatitis, 13 cases of which were focal; 33 with pancreatic carcinoma, and 25 with a normal pancreas) were evaluated. One radiologist measured the CT attenuation of the pancreatic parenchyma and pancreatic masses in both the pancreatic and hepatic phases of imaging. The mean CT attenuation value of the pancreatic parenchyma in patients with autoimmune pancreatitis was compared with that in patients with a normal pancreas. The mean CT attenuation value of the focal masses in the focal form of autoimmune pancreatitis was compared with that of carcinomas. RESULTS In the pancreatic phase, the mean CT attenuation value of the pancreatic parenchyma in patients with autoimmune pancreatitis was significantly lower than that in patients with a normal pancreas (autoimmune pancreatitis, 85 HU; normal pancreas, 104 HU; p < 0.05). In the hepatic phase, however, the mean CT attenuation values were not significantly different (autoimmune pancreatitis, 96 HU; normal pancreas, 89 HU; p = 0.6). In the pancreatic phase, the mean CT attenuation value of the mass in autoimmune pancreatitis was not significantly different from that of carcinoma (autoimmune pancreatitis, 71 HU; carcinoma, 59 HU; p = 0.06), but in the hepatic phase, the value was significantly higher than that of carcinoma (autoimmune pancreatitis, 90 HU; carcinoma, 64 HU; p < 0.001). CONCLUSION At dual-phase CT, the enhancement patterns of the pancreas and pancreatic masses in patients with autoimmune pancreatitis are different from those of pancreatic carcinoma and normal pancreas.

Abdominal Findings in Hereditary Hemorrhagic Telangiectasia: Pictorial Essay on 2D and 3D Findings with Isotropic Multiphase CT

The rapid evolution in multidetector computed tomographic (CT) technology has produced improvements in temporal and spatial resolution, leading to greater recognition of the spectrum of abdominal findings in hereditary hemorrhagic telangiectasia (HHT). In this multisystem vascular disorder, the abdominal findings are predominantly within the liver. Hepatic vascular lesions in HHT range from tiny telangiectases to transient perfusion abnormalities and large confluent vascular masses. Focal hepatic lesions are often associated with arteriovenous, arterioportal, or portovenous shunts. Pancreatic, splenic, and other vascular abnormalities are also observed because they are included in the field of view. By taking advantage of the increased z-axis spatial resolution and faster scanning times, and by using a bolus tracking technique, multiphase CT can be used to identify hepatic and extrahepatic lesions in HHT and to characterize the associated vascular shunts. Coronal maximum intensity projection images are particularly helpful in depiction of small hepatic vascular lesions.