The OSPE.

OBJECTIVES: Resident assessment tends to consist of multiple-choice examinations, even in nuanced areas, such as quality assurance. Internal medicine and many other specialties use objective structured clinical examinations, or OSCEs, to evaluate residents. We adapted the OSCE for pathology, termed the Objective Structured Pathology Examination (OSPE). METHODS: The OSPE was used to evaluate first- and second-year residents over 2 years. The simulation included an anatomic pathology sign-out session, where the resident could be evaluated on diagnostic skills and knowledge of key information for cancer staging reports, as well as simulated frozen-section analysis, where the resident could be evaluated on communication skills with a "surgeon." The OSPE also included smaller cases with challenging quality issues, such as mismatched slides or gross description irregularities. All cases were scored based on the Pathology Milestones created by the Accreditation Council for Graduate Medical Education. RESULTS: Using this OSPE, we were able to demonstrate that simulated experiences can be an appropriate tool for standardized evaluation of pathology residents. CONCLUSIONS: Yearly evaluation using the OSPE could be used to track the progress of both individual residents and the residency program as a whole, identifying problem areas for which further educational content can be developed.

Extracellular and intracellular melanin in inflammatory middle ear disease.

OBJECTIVES/HYPOTHESIS: Melanin is a pigmented polymer with a known role in dermal solar protection. In vertebrates, melanogenesis has been reported in leukocyte populations, suggesting a potential role in innate immunity. In this study, we report the novel finding of melanin associated with chronic inflammation and speculate on its potential role in the middle ear and mastoid. STUDY DESIGN: Retrospective review of case series. METHODS: Medical records of six patients who demonstrated melanin in the ear were reviewed. RESULTS: Six patients from 1 to 63 years of age were identified with extracellular melanin and melanin-laden histiocytes within the middle ear and/or mastoid air cells at time of surgery. Concurrent intraoperative findings included cholesteatoma (n = 3), chronic suppurative otitis media (n = 2), and coalescent mastoiditis (n = 1). Histologically, extracellular melanin and melanin-laden histiocytes were identified by Fontana-Masson stain; absence of melanocytes was confirmed by the absence of Melan-A staining. One patient had a positive stain for CD163 (a marker for macrophages). CONCLUSION: This case series is the first demonstration of melanin within middle ear mucosa without melanocytes in immediate proximity or metastatic melanocytic lesions. Melanin's presence in the setting of inflammation suggests that there may be a heretofore unreported link between the pigmentary and immune systems in the middle ear. LEVEL OF EVIDENCE: 4.

Advanced liver fibrosis: diagnosis with 3D whole-liver perfusion MR imaging--initial experience.

Institutional review board approval and informed consent were obtained for this HIPAA-compliant study. The purpose of this study was to prospectively evaluate sensitivity and specificity of various estimated perfusion parameters at three-dimensional (3D) perfusion magnetic resonance (MR) imaging of the liver in the diagnosis of advanced liver fibrosis (stage >or= 3), with histologic analysis, liver function tests, or MR imaging as the reference standard. Whole-liver 3D perfusion MR imaging was performed in 27 patients (17 men, 10 women; mean age, 55 years) after dynamic injection of 8-10 mL of gadopentetate dimeglumine. The following estimated perfusion parameters were measured with a dual-input single-compartment model: absolute arterial blood flow (F(a)), absolute portal venous blood flow (F(p)), absolute total liver blood flow (F(t)) (F(t) = F(a) + F(p)), arterial fraction (ART), portal venous fraction (PV), distribution volume (DV), and mean transit time (MTT) of gadopentetate dimeglumine. Patients were assigned to two groups (those with fibrosis stage or= 3), and the nonparametric Mann-Whitney test was used to compare F(a), F(p), F(t), ART, PV, DV, and MTT between groups. Receiver operating characteristic curve analysis was used to assess the utility of perfusion estimates as predictors of advanced liver fibrosis. There were significant differences for all perfusion MR imaging-estimated parameters except F(p) and F(t). There was an increase in F(a), ART, DV, and MTT and a decrease in PV in patients with advanced fibrosis compared with those without advanced fibrosis. DV had the best performance, with an area under the receiver operating characteristic curve of 0.824, a sensitivity of 76.9% (95% confidence interval: 46.2%, 94.7%), and a specificity of 78.5% (95% confidence interval: 49.2%, 95.1%) in the prediction of advanced fibrosis.

Diffusion-weighted MRI for quantification of liver fibrosis: preliminary experience.

OBJECTIVE: The purpose of this study was to evaluate our preliminary experience using diffusion-weighted MRI for quantification of liver fibrosis. SUBJECTS AND METHODS: Diffusion-weighted MRI with single-shot echo-planar technique at b values of 50, 300, 500, 700, and 1,000 s/mm2 was prospectively performed on 23 patients with chronic hepatitis and on seven healthy volunteers. The apparent diffusion coefficient (ADC) was measured in four locations in the liver. Liver biopsy results (n = 19) were retrospectively reviewed by two hepatopathologists in consensus to determine stage of fibrosis and grade of inflammation. A Mann-Whitney test was used to compare the ADCs between patients classified with respect to having stage 2 or greater versus stage 1 or less fibrosis and stage 3 or greater versus stage or less 2 fibrosis. Receiver operating characteristics analysis was used to assess the performance of ADC in prediction of the presence of stage 2 or greater and stage 3 or greater fibrosis. RESULTS: Using a b value of 500 s/mm2 and all combined b values, we found significantly lower hepatic ADCs in stage 2 or greater versus stage 1 or less fibrosis and stage 3 or greater versus stage 2 or less fibrosis. The mean ADCs (x 10(-3) mm2/s) with all b values were 1.47 +/- 0.11 (SD) versus 1.65 +/- 0.10 for stage 2 or greater versus stage 1 or less fibrosis (p < 0.001) and 1.44 +/- 0.07 versus 1.66 +/- 0.10 for stage 3 or greater versus stage 2 or less fibrosis (p <0.001). Hepatic ADC was a significant predictor of stage 2 or greater and stage 3 or greater fibrosis, with areas under the curve of 0.896 and 0.896, sensitivity of 83.3% and 88.9%, and specificity of 83.3% and 80.0% (ADC with all b values, 1.54-1.53 x 10(-3) mm2/s or less). CONCLUSION: Diffusion-weighted MRI can be used for prediction of the presence of moderate and advanced liver fibrosis.