The Impact of Rapid On-site Evaluation on Diagnostic Performance of Computed Tomography-Guided Core Needle Biopsy in Lung Cancer.

PURPOSE: Rapid on-site-evaluation (ROSE) is a technique aimed at improving the diagnostic performance of computed tomography (CT)-guided core needle biopsy (CNB) in lung cancer. The aim of this retrospective study was to investigate the impact of ROSE on the rate of nondiagnostic specimens and on accuracy computed on diagnostic specimens. MATERIALS AND METHODS: During a 3-year period, 417 CT-guided CNBs were performed at our center. The biopsies were retrospectively classified into 2 groups: 141 procedures were assisted by ROSE and 276 were not. All of them were reviewed for clinical, procedural, and pathological data. Pathology results were classified as diagnostic (positive or negative for malignancy) or nondiagnostic. The results were compared with the final diagnosis after surgery or clinical follow-up. Nondiagnostic rate, sensitivity/specificity/negative predictive value/positive predictive value for the ROSE and non-ROSE groups were calculated. Finally, procedural complications and the adequacy of the specimens for the molecular analysis were recorded. RESULTS: The study evaluated 417 CNBs (mean patients' age 71 years, 278 men). Nondiagnostic rates with and without ROSE were 4% (6/142) and 11% (29/276), respectively ( P = 0.028). Sensitivity/specificity/negative predictive value/positive predictive value with and without ROSE did not show statistically significant differences, and no difference in major/minor complication rates was observed between the 2 groups. The adequacy of specimen for subsequent molecular analysis was 100% with (42/42) and 82% without ROSE (51/62). CONCLUSIONS: Rapid on-site-evaluation reduced the rate of nondiagnostic specimens by 50% with no change in complication rates or accuracy and increased by 20% the chances of a successful subsequent molecular analysis.

Omental infarction and its mimics: imaging features of acute abdominal conditions presenting with fat stranding greater than the degree of bowel wall thickening.

The segmental omental infarction is a rare self-limited disorder presenting with aspecific clinical symptoms that may mimic several acute abdominal conditions. Therefore, a correct noninvasive diagnosis is important because treatment approaches range from monitoring to surgery. As omental infarction results in an important fat stranding that is much greater than the degree of bowel wall thickening, it suggests a narrower differential diagnosis: appendicitis, diverticulitis, epiploic appendagitis, and mesenteric panniculitis. In this pictorial essay, we point out the importance of imaging in identifying this typical sign allowing alternate diagnoses such as segmental omental infarction that can be conservatively managed.

Monitoring of Thermal-Induced Changes in Liver Stiffness During Controlled Hyperthermia and Microwave Ablation in an Ex Vivo Bovine Model Using Point Shear Wave Elastography.

PURPOSE: To investigate liver stiffness changes-evaluated by point shear wave elastography (pSWE)-in controlled hyperthermia and microwave ablation (MWA) in an ex vivo animal model. MATERIALS AND METHODS: Five samples of ex vivo bovine liver were uniformly heated to temperatures ranging from 40 to 100 °C. B-mode ultrasound imaging and pSWE were acquired simultaneously, and shear wave velocity (SWV) was measured in a region of interest (ROI). The threshold value of SWV at 60 °C (avg60) was identified. Subsequently, MWA was performed in 11 liver samples at 60 W until avg60 + 0.5 m/s was reached. SWV was measured in ROIs at 10-40 mm from the antenna feed. The correlation of mean values of SWV with location (within, border, or outside necrotic area) at gross pathology was evaluated. RESULTS: In controlled hyperthermia experiments, a steep transition in liver stiffness was observed at 63.0 ± 2.4 °C (SWV 3.54 ± 0.68 m/s). Avg60 was of 2.5 m/s. In 8/9 MWA experiments, interrupted when SWV of 3 m/s was measured, the ROI was at the inner side of the necrotic area border at pathology (accuracy 89%). No correlation between SWV values for outside, border, and within necrosis could be identified. CONCLUSIONS: pSWE can provide a velocity threshold predictive of the presence of coagulation necrosis during MWA in ex vivo liver model. However, pSWE is not able to reliably capture changes in stiffness within, at the border, and outside the necrotic zone in this experimental model.