Dimensionality and the category of major depressive episode

Major depressive episode (MDE) is a chronic disease typified by episodes that remit and recur. It is a major contributor to the burden of disease. The diagnosis of a disorder is an expert opinion that the disorder is present. The nine symptoms of MDE exist on dimensions of greater or lesser intensity, persistence over time, change in usual state, distress and impairment. It is the clinician's task to judge whether the elicited symptoms warrant the diagnosis. The surprise is that trained clinicians can do this reliably and that diagnostic interviews and questionnaires can emulate this process. The distribution of symptoms in community surveys is exponential, with no obvious discontinuity at the diagnostic threshold. Taxometric and primary care studies confirm this. The number of symptoms predicts severity, comorbidity, family history, disability, help seeking and treatment recommendations. The latent structure of mental disorders places MDE in the distress misery cluster. Measures of well-being, distress, disability and neuroticism correlate with the number of symptoms but the relation is not perfect. The Patient Health Questionnaire is derived from the diagnostic criteria and does not suffer this limitation. The introduction of measures like this would acknowledge dimensionality, would facilitate recognition, guide treatment, and be acceptable to consumers, providers and funders.     

Semiautomated MIP images created directly on 16-section multidetector CT console for evaluation of living renal donors

Institutional Review Board approval was obtained and informed consent was waived for this HIPAA-compliant study. The aim of this study was to retrospectively compare the accuracy of semiautomated maximum intensity projection (MIP) images created at a 16-section multidetector CT console with three-dimensional (3D)-workstation-generated images for the definition of renal donor anatomy, with intraoperative findings as a reference standard. In examining 40 renal donors (21 men and 19 women; age range, 24-56 years; mean age, 40.4 years), the sensitivity and accuracy for mapping donor anatomy by two readers were greater than 95%, interobserver agreement was excellent (kappa = 0.89-1.00). The 95% confidence interval for sensitivity was also calculated. Simple MIPs compared well with 3D-workstation images. MIPs from a predesigned protocol on the scanner console were generated more quickly than similar images from 3D workstations; postprocessing demands (eg, for renal donors) can be quickly fulfilled at the scanner console itself. The average time to generate simple MIPs at the console was 3.4 minutes (range, 1.7-4.4 minutes), and 22.3 minutes (range, 15-30 minutes) to create images at the 3D workstation.     

Acute cholecystitis: MR findings and differentiation from chronic cholecystitis

PURPOSE: To retrospectively determine the sensitivity and specificity of magnetic resonance (MR) imaging for differentiation between acute and chronic cholecystitis, with histopathologic analysis as the reference standard. MATERIALS AND METHODS: Institutional review board approval with waived informed consent was obtained for this HIPAA-compliant study. Four reviewers blinded to the cholecystitis type but aware that cholecystitis was present retrospectively evaluated MR images for predetermined findings in 32 patients (15 male, 17 female; mean age +/- standard deviation, 55 years +/- 20) with histopathologically proved acute or chronic cholecystitis. The final MR diagnoses and MR findings in both groups were compared with each other and with the histopathologic diagnoses to determine the sensitivity and specificity of MR imaging. Chi(2) tests were used to detect differences in MR findings between the acute and chronic cholecystitis groups. RESULTS: MR imaging sensitivity and specificity for detection of acute cholecystitis were 95% (18 of 19 patients) and 69% (nine of 13 patients), respectively. The sensitivities of increased gallbladder wall enhancement and increased transient pericholecystic hepatic enhancement were 74% (14 of 19 patients) and 62% (10 of 16 patients), respectively. Both findings had 92% (12 of 13 patients) specificity. Sensitivities of increased wall thickness, pericholecystic fluid, and adjacent fat signal intensity changes were 100% (19 of 19 patients), 95% (18 of 19 patients), and 95% (18 of 19 patients), respectively; specificities were 54% (seven of 13 patients), 38% (five of 13 patients), and 54% (seven of 13 patients), respectively. Pericholecystic abscess, intraluminal membranes, and wall irregularity or defect each had 100% (13 of 13 patients) specificity; sensitivities were 11% (two of 19 patients), 26% (five of 19 patients), and 21% (four of 19 patients), respectively. Increased gallbladder wall enhancement (P<.001) and increased transient pericholecystic hepatic enhancement (P=.003) were the most significantly different between acute and chronic cholecystitis. CONCLUSION: Increased gallbladder wall enhancement and increased transient pericholecystic hepatic enhancement had the highest combination of sensitivity and specificity for the diagnosis and differentiation of acute and chronic cholecystitis.     

Focal hepatic activity during ventilation-perfusion scintigraphy due to systemic-portal shunt due to superior vena cava obstruction from histoplasmosis-induced fibrosing mediastinitis

A 59-year-old woman with a history of fibrosing mediastinitis secondary to histoplasmosis diagnosed on mediastinoscopy presented with dyspnea. A ventilation-perfusion scan demonstrated decreased perfusion to the entire right lung. In addition, the perfusion images demonstrated focal abnormal activity in part of the liver. On computed tomography of the chest, there was significant soft tissue opacification in the mediastinum occluding the right pulmonary artery, with passage of the injected contrast via collateral vessels to the liver. The main collateral pathway was via the right internal thoracic vein and the umbilical vein. Pulmonary angiography confirmed complete occlusion of the right pulmonary artery.     

Pancreatic cancer: correlation of MR findings, clinical features, and tumor grade

PURPOSE: To assess the frequency of occurrence of poorly-marginated and focally-defined pancreatic ductal adenocarcinoma by MRI and to determine whether these appearances correlate with clinical features and histopathological grade. MATERIALS AND METHODS: Institutional review board with waiver of informed consent was obtained for this HIPAA compliant study. A total of 33 patients (16 female, 17 male, mean age = 63.5 +/- 12.8, ranging from 41 to 80 years) with histopathologically-proven pancreatic ductal adenocarcinoma who underwent MR examination between August 2000 and February 2005 were retrospectively evaluated. Clinical data and histopathological tumoral grade were obtained from clinical charts; nine of 33 patients were excluded of the histopathological evaluation since their diagnosis was performed by fine needle aspiration biopsy and it was not possible to obtain the histopathological grade. Two radiologists reviewed all cases independently to identify whether cancers were poorly-marginated or focally-defined. Agreement between radiologists was assessed using the kappa coefficient. The overall correlation between imaging findings, clinical features, and histopathological grade was assessed with contingency tables using the Fisher's exact test. RESULTS: Of the 33 patients, nine (27.2%) were classified as poorly-marginated and 24 (72.8%) as focally-defined. Agreement between the two reviewers was excellent (k = 0.92, 95% confidence interval (CI) = 0.78-1.0). Poorly-marginated cancers exhibited well- to moderately-differentiated histopathology in 71.4% of cases, while focally-defined cancers had well- to moderately-differentiated histopathology in 17.6% of cases, P = 0.02. CONCLUSION: A poorly-marginated appearance of pancreatic ductal carcinoma on MRI is not uncommon. These cancers exhibited statistically significant moderate- to well-differentiated histopathology compared to focally-defined cancers.     

Ballistic arterial trauma to the lower extremity: recent South African experience

The aim of this study was to determine the current outcome of gunshots to the arteries of the lower extremity. The authors conducted a retrospective analysis of 104 patients with gunshots to the femoral (n=71) and popliteal (n=33) artery. One hundred four patients presented over the 60-month period. Ninety-six (92%) were male and eight of 104 female. Ninety-nine were gunshot injuries, five from shotguns. Nine patients had injury to the common femoral artery, 62 patients had injury to the superficial femoral artery, and 33 had popliteal artery injury. One patient died in the emergency room and another died in the postoperative period, giving an overall in-hospital mortality of two of 104 (1.9%). Forty-three of 70 femoral reconstructions had completion angiograms compared with 20 of 32 popliteal artery reconstructions (P=1). Nineteen of 63 (30%) of the completion angiograms prompted revision of the reconstruction. Of the 63 patients who had completion angiograms, two of 63 (3%) required amputation. Seven of 39 (18%) patients who did not have completion angiograms required amputation (P = 0.025). Including the primary amputation, there were 10 amputations in the 103 patients (9.7%) who survived to undergo operation. Ballistic arterial trauma of the lower limb leads to significant disability. Completion arteriography leads to revision of the reconstruction in nearly one-third of instances and significantly reduces amputation rate.