Charles D. Levine

CT findings of bowel and mesenteric injury.

Bowel and mesenteric injuries are common sequelae of blunt abdominal trauma. CT represents a valuable modality in the diagnosis of bowel and mesenteric injuries. While certain findings on CT are highly specific, such as free air and extravasation of oral contrast agent, they are insensitive and seen only in the minority of patients. Therefore, radiologists must focus their attention on the bowel wall and mesentery to improve their diagnostic accuracy in these injuries. Bowel wall thickening and/or abnormal bowel wall enhancement must be noted. Mesenteric abnormalities, which can consist of mesenteric infiltration, interloop fluid, or fluid trapped in the leaves of the small bowel mesentery, may be crucial yet subtle clues. Knowledge of their typical appearance may aid in their diagnosis. This pictorial essay illustrates the range of findings in bowel and mesenteric injuries as well as possible pitfalls to help in their prompt recognition and diagnosis.

Tumor lesion detection: when is integrated positron emission tomography/computed tomography more accurate than side-by-side interpretation of positron emission tomography and computed tomography?

Objectives: To determine if there is added value to oncology studies performed with a dedicated in-line positron emission tomography (PET)/computed tomography (CT) scanner as compared with PET read side by side with diagnostic CT (DCT). Methods: Forty-one consecutive oncology patients referred for PET/CT who had contemporary DCT scans for review were enrolled. Body regions assessed on a DCT scan were assessed on PET/CT and by side-by-side reading of PET and DCT (SBS PET/DCT). Lesions identified on DCT, the CT portion of PET/CT, SBS PET/DCT, and the reading of fused PET/CT images were scored as benign or malignant. The PET portion of the PET/CT study was read by 2 teams: the first read the SBS PET/DCT scan and the other read the complete fused PET/CT scan. For discordant lesions, the final diagnosis was determined by pathologic findings (n = 6) or imaging follow-up (n = 21). Results: Twenty-seven (16.1%) of the 168 lesions were discordant when comparing analysis of fused PET/CT and SBS PET/DCT. Sixteen (9.5%) were fundamentally discordant, and 11(6.6%) were discordant in degree of confidence. For all discordant lesions only, the sensitivity, specificity, negative predictive value, positive predictive value, and accuracy for PET/CT were 100%, 33%, 100%, 94%, and 78%, respectively, and for SBS PET/DCT, they were 38%, 50%, 19%, 73%, and 30%, respectively (P < 0.001 for sensitivity, P = not specific for specificity). The 2 main causes for misclassification on SBS PET/DCT were incorrect localization (n = 12) and changes occurring in the time gap between DCT and PET/CT (n = 4). Conclusions: In-line PET/CT offers better lesion localization in comparison to the visual fusion of PET and CT, especially for small lymph nodes, lesions adjacent to mobile organs, or lesions adjacent to the chest or abdominal wall.

Pelvic marrow in adults

The appearance of hematopoietic marrow in magnetic resonance (MR) imaging is variable and differences between normal and pathologic marrow may be subtle. To aid in the evaluation of this problem, we reviewed 82 consecutive pelvic MR examinations in men with no evidence of osseous metastases. Images were evaluated with regard to the overall fraction of residual hematopoietic marrow present and the characteristics of this marrow. The patient population in our study was older (mean age 66 years) than the patient populations in previous papers documenting normal marrow patterns. The overall amount of hematopoietic marrow present was less in this older patient population, with 80% of patients having less then 40% residual hematopoietic marrow. A consistent pattern of morphologic change was noted as hematopoietic marrow converted to fatty marrow with increasing age. Initially, hematopoietic marrow tended to appear diffuse, heterogeneous, and with poorly defined margins on MR imaging. As conversion to fatty marrow continued, hematopoietic marrow became more focal and sharply defined, usually in the form of islands of residual hematopoietic marrow. Periarticular hematopoietic marrow predominated in the sacroiliac region (72% of patients) with little residual hematopoietic marrow noted in the symphysis pubis (5%) and hip joints (30%). Hematopoietic marrow persisted longer in juxtacortical locations (87%), was always symmetric (100%), remained less intense than fat on T2-weighted images (100%), and usually had a central focus of fat (98%). These morphologic criteria may be of value in establishing the MR appearance and patterns of marrow in the pelvis, and in the recognition and confident diagnosis of foci of hematopoietic marrow.

Narrowing of the upper abdominal inferior vena cava in patients with elevated intraabdominal pressure

AbstractBackground: Previous investigators have suggested that narrowing of the suprahepatic inferior vena cava (IVC) occurs in patients with increased intraabdominal pressure (IAP). Subjects and methods: We retrospectively reviewed 59 contrast-enhanced computed tomographic (CT) scans performed over a 2-year period in patients with evidence of increased IAP. We also reviewed CT scans performed in a control group of 30 normal patients. The intrahepatic and suprahepatic IVC segments were assessed for narrowing. Results: Narrowing of the suprahepatic IVC was never observed in the patients with elevated IAP. Slit-like narrowing of the upper intrahepatic IVC was noted in 11 (44%) of 25 patients; the intrahepatic IVC was not evaluated in 34 other patients with liver abnormalities or unsatisfactory opacification of the intrahepatic IVC. In control subjects, narrowing was not observed in either the intrahepatic or suprahepatic IVC. Conclusion: Narrowing of the upper intrahepatic IVC can be seen in some patients with increased IAP. The cause and significance of this phenomenon remain to be determined.

Sarcoid myopathy: Imaging findings

Sarcoidosis is a granulomatous multisystem disorder that may uncommonly involve muscle. Muscular sarcoid may be nodular, atrophic myopathic, or acute myositic. We illustrate a case of the myopathic type of muscular sarcoid that is unusual because the abdominal wall muscles, rather than the extremity muscles, were involved. Muscular involvement by sarcoid should be considered in the differential diagnosis of focal muscle disease, especially in a patient with a known history of sarcoid. The presence of typical bilateral hilar adenopathy on a chest radiograph as well as the presence of abdominal findings (hepatosplenomegaly and retroperitoneal adenopathy) may help establish the diagnosis. Otherwise, sonographically guided biopsy may be necessary for definitive diagnosis.

Transcapsular arterial collateralization of a liver allograft after hepatic artery occlusion in an adult: color Doppler ultrasonographic diagnosis.

Thrombosis of the HA after OLT usually causes severe hepatobiliary ischemic damage and is an indication for retransplantation.1 CCDU is the premier noninvasive technique used to screen for HA thrombosis and stenosis.2 Particularly in children with HA compromise, arterial collaterals may develop and mimic a patent HA during CCOU.l Arterial collateralization after HA thrombosis has been reported rarely in adults.4..5 In virtually all reported cases of collateralized HA thrombosis of which we are aware, the collaterals have been located in the vicinity of the porta hepatis. In native livers, HA ligation is followed rapidly by extensive arterial collateralization, typically via the phrenic, intercostal, and gastric arteries.6 We report a

CT evaluation of pararectal varices

PURPOSE This study was undertaken to determine the prevalence of pararectal varices on CT scan in patients with portal hypertension and to see if dilatation of the inferior mesenteric vein (IMV) or the presence of pararectal varices on CT correlates with rectal varices noted on colonoscopy. METHOD We reviewed 83 consecutive CT scans of the abdomen and pelvis performed in patients with portal hypertension. The size and prevalence of pararectal varices were determined. Correlation with colonoscopic and endoscopic reports was performed. The diameter of the IMV was compared in those patients with pararectal varices with that in those patients without, as was the presence of esophageal varices. RESULTS Twenty patients (24%) had CT evidence of pararectal varices, ranging from 5 to 11 mm in diameter (mean 7.8 mm). Colonoscopic correlation was available in 30 patients. Of these, 6 of 30 (20%) had pararectal varices on CT and no rectal varices on colonoscopy, 3 of 30 (10%) had pararectal varices on CT and rectal varices on colonoscopy, and 3 of 30 (10%) had no pararectal varices on CT but did have rectal varices on colonoscopy. Endoscopic correlation (available in 48 patients) demonstrated esophageal varices in 88% of patients with rectal or pararectal varices and in 66% of patients without rectal or pararectal varices (p = 0.170). The IMV was significantly larger in patients with pararectal varices (mean diameter 7.5 mm, SD 2.3) as compared with those without (mean diameter 5.8 mm, SD 2.0) (p = 0.014). However, in patients with colonoscopically proven rectal varices, only two of six (33%) had an IMV diameter of > or = 7 mm. CONCLUSION Inclusion of the pelvis on CT scans of patients with portal hypertension can yield further information about the presence and extent of pararectal venous collaterals, which may be of particular importance in those patients requiring pelvic surgery. The presence of pararectal varices on CT and the diameter of the IMV do not correlate with the presence of rectal varices on colonoscopy. Decompression of portal hypertension by rectal and pararectal varices does not result in a decreased incidence of esophageal varices.

Inflammatory fibroid polyp of the esophagus in an HIV-infected individual: Case study

We report an unusual case of a large esophegeal inflammatory fibroid polyp in a man infected with the human immunodeficiency virus complaining of dysphagia. Barium studies and computed tomography demonstrated a long, submucosal-appearing, distal esophageal mass which extended into a hiatal hernia. Inflammatory fibroid polyps should be considered in the differential diagnosis of submucosal and polypoid esophageal masses, although distinctive radiographic features are not found.

Dilatation of the inferior vena cava in patients with cirrhotic portal hypertension: Causes and imaging findings

Dilatation of the inferior vena cava is a frequent finding in patients with cirrhosis and portal hypertension, and may be produced by various mechanisms. In this article we illustrate the spectrum of causes and appearances of inferior vena caval dilatation in patients with cirrhosis and portal hypertension.

Pleural effusions associated with acute pancreatitis: Incidence and appearance based on computed tomography

Recognition of pleural effusions in acute pancreatitis is important since it carries prognostic implications. This study evaluates the incidence and characteristics of pleural effusions on computed tomography (CT) of patients with mainly an alcohol ingestion etiology of acute pancreatitis. A review of medical records and abdominal CT scans in 50 patients with clinical and laboratory evidence of acute pancreatitis was carried out. All patients were referred for abdominal CT scanning based on an initial clinical presentation consistent with acute pancreatitis and had confirmatory elevation of the corresponding serum enzyme levels. The presence, laterality, and size of any pleural effusions were recorded from the initial sections through the lung bases.Based on a review of medical records, 36 patients (72%) had an alcohol-related etiology of acute pancreatitis.Overall, 10 patients (20%) with acute pancreatitis had pleural effusions on abdominal CT imaging. Five of the effusions were bilateral, three were unilateral right sided, and two were unilateral left sided. Nine of the effusions were small (<1 cm in maximal height) or medium (1–2 cm) in size.Small and medium-sized pleural effusions are not uncommon in acute pancreatitis. The higher incidence in this study compared to that in earlier reports likely represents the increased sensitivity of cross-sectional imaging for small amounts of pleural fluid. The absence of left-sided effusion predominance in our study group is contrary to much of the earlier literature and may reflect demographic factors, such as etiology and previous history of pancreatitis, although statistical variability must also be considered.