Diagnostic performance of MDCT in identifying closed loop small bowel obstruction.

PURPOSE: To assess the diagnostic performance of MDCT in the diagnosis of closed loop small bowel obstruction. MATERIALS AND METHODS: One hundred fifty patients with CT reports including "small bowel obstruction (SBO)" between 1/30/2011 and 12/4/2012 were included (65 men, 85 women, mean age 63 years). CT examinations were independently and blindly reviewed by five radiologists to determine the presence of closed loop obstruction (CL-SBO) and to assess findings of bowel ischemia. Clinical records were reviewed to determine management and operative findings. Using operative findings as a gold standard, reader agreement for the diagnosis of and the CT findings associated with CLO was analyzed using Pearson's correlation (r). Positive predictive value (PPV) and negative predictive value for the diagnosis of CL-SBO and CT signs of bowel ischemia were analyzed. RESULTS: Eighty-eight of 150 patients underwent operative intervention for SBO and 24/88 were considered CL-SBO operatively. Average reader sensitivity and specificity for CL-SBO was 53 % (95 % CI 44-63 %) and 83 % (95 % CI 79-87 %). Reader agreement on CL-SBO was poor to moderate (K = 0.39-0.63). Reader agreement for CT signs of bowel ischemia resulting in a diagnosis of CL-SBO was weak (r = 0.19-0.32). CONCLUSION: The CT diagnosis of CL-SBO is complex and associated imaging findings have variable sensitivity for predicting a closed loop operative diagnosis. CT can be helpful in excluding a closed loop component in patients with SBO.

Concordance of hypervascular liver nodule characterization between the organ procurement and transplant network and liver imaging reporting and data system classifications.

PURPOSE: To determine the rate of agreement between the Organ Procurement and Transplant Network (OPTN) and Liver Imaging Reporting and Data System (LI-RADS) classifications for hypervascular liver nodules at least 1 cm in diameter, and for patient eligibility for hepatocellular/MELD (Model for Endstage Liver Disease) exception points. MATERIALS AND METHODS: This retrospective study was approved by our Institutional Review Board and was compliant with the Health Insurance Portability and Accountability Act. The requirement for informed consent was waived. This study included 200 hypervascular hepatocellular nodules at least 1 cm in diameter on computed tomography (CT) or magnetic resonance imaging (MRI) examinations in 105 patients with chronic liver disease. Three radiologists blinded to clinical data independently evaluated nodule characteristics, including washout, capsule, size, and size on prior examination. Based on those characteristics, nodules were automatically classified as definite hepatocellular carcinoma (HCC) or not definite HCC using both the OPTN and LI-RADS classifications. Using these classifications and the Milan criteria, each examination was determined to be "below transplant criteria," "within transplant criteria," or "beyond transplant criteria." Agreement was assessed between readers and classification systems, using Fleiss' kappa, intraclass correlation coefficients (ICCs), and simple proportions. RESULTS: Interreader agreement was moderate for nodule features (κ = 0.59-0.69) and nodule classification (0.66-0.69). The two systems were in nearly complete agreement on nodule category assignment (98.7% [592/600]) and patient eligibility for transplant exemption priority (99.4% [313/315]). A few discrepancies occurred for the nodule feature of growth (1.3% [8/600]) and for nodule category assignment (1.3% [8/600]). CONCLUSION: Agreement between the OPTN and LI-RADS classifications is very strong for categorization of hypervascular liver nodules at least 1 cm in diameter, and for patient eligibility for hepatocellular/MELD exception points. Interreader variability is much higher than intersystem variability.

Role of breast ultrasound and mammography in evaluating patients presenting with focal breast pain in the absence of a palpable lump.

To determine if ultrasound and/or mammography is helpful in detecting breast cancers in patients presenting with focal breast pain. Patients who presented between February 2008 and April 2011 with focal breast pain without a lump were included in the study. The mammographic and US findings were retrospectively reviewed. BIRADS 0, 4, and 5 were considered positive on mammogram while BIRADS 4 and 5 were considered positive on US. The efficacy of mammogram-alone, ultrasound-alone, and in combination to detect breast cancer was evaluated. The performance of mammography for detecting any mass lesions that were present on subsequent US was also evaluated. A total of 257 patients were evaluated with US and 206 (80.1%) of these also had mammograms prior to the US. Cancer incidence was 1.2% (n = 3). The sensitivity, specificity, PPV, and NPV of mammogram-alone and US-alone for detection of breast cancer in these patients were 100%, 87.6%, 10.7%, 100% and 100%, 92.5%, 13.6%, and 100%, respectively, while for combined mammogram and US was 100%, 83.7%, 8.3%, and 100%. The sensitivity, specificity, PPV, and NPV of mammogram for identifying an underlying suspicious mass lesion that was subsequently detected by US was 58%, 91%, 39%, and 95%. The NPV of a BIRADS 1 mammogram for any underlying mass lesion was 75%. Addition of an ultrasound to a mammogram did not detect additional cancers; likely due to low cancer incidence in these patients. However, US detected underlying mass lesions in 25% cases with a BIRADS 1 mammogram result.

Preliminary evaluation of ultra-high pitch computed tomography enterography.

BACKGROUND: CT enterography (CTE) is a valuable tool in the management of patients with inflammatory bowel disease. Reducing imaging time, reduced motion artifacts, and decreased radiation exposure are important goals for optimizing CTE examinations. PURPOSE: To assess the potential impact of new CT technology (ultra-high pitch CTE) for the ability to reduce scan time and also potentially reduce radiation exposure while maintaining image quality. MATERIAL AND METHODS: This retrospective study compared 13 patients who underwent ultra-high pitch CTE with 25 patients who underwent routine CTE on the same CT scanner with identical radiation emission settings. Total scan time and radiation exposure were recorded for each patient. Image quality was assessed by measurement of image noise and also qualitatively by two independent observers. RESULTS: Total scan time was significantly lower for patients who underwent ultra-high pitch CTE (2.1 s ± 0.2) than by routine CTE (18.6 s ± 0.9) (P < 0.0001). The mean radiation exposure for ultra-high pitch CTE was also significantly lower (10.1 mGy ± 1.0) than routine CTE (15.8 mGy ± 4.5) (P < 0.0001). No significant difference in image noise was found between ultra-high pitch CTE (16.0 HU ± 2.5) and routine CTE (15.5 HU ± 3.7) (P > 0.74). There was also no significant difference in image quality noted by either of the two readers. CONCLUSION: Ultra-high pitch CTE can be performed more rapidly than standard CTE and offers the potential for radiation exposure reduction while maintaining image quality.

Use of high-pitch dual-source computed tomography of the abdomen and pelvis to markedly reduce scan time: clinical feasibility study.

BACKGROUND: Increasing image pitch in computed tomographic (CT) imaging is a method through which scan time can be reduced, which can reduce motion artifacts. In this study, we assess the clinical feasibility of ultrahigh-pitch CT imaging made possible by dual-source CT. METHODS: Image pitch, total scan time, and image quality assessments were compared between 45 patients who underwent a high-pitch dual-source CT and 34 patients imaged by standard CT technique. Image noise and diagnostic image quality were assessed by 2 independent blinded readers on a 5-point scale. RESULTS: Mean pitch of high-pitch CT was 2.5 (mean scan time, 1.9 seconds) compared with the standard CT mean pitch of 0.6 (mean scan time, 9.8 seconds). There was no statistically significant difference in image noise between high-pitch CT (12.6) and standard CT (12.0); P > 0.3. Although reader 1 rated standard CT as superior to high-pitch CT (P 0.005), reader 2 rated no significant difference. No high-pitch CT studies were rated as limited diagnostically by either reader. CONCLUSION: High-pitch dual-source CT can reduce scan time while leading to minor losses of image quality, which may be useful in some patients.

Interleukin-6 inhibits cell proliferation in a rat model of hepatocellular carcinoma.

BACKGROUND: Interleukin-6 (IL-6) plays a critical role in normal hepatic growth and liver regeneration. The aims of the present study are to determine the expression of components of IL-6 signaling in an in vivo model of hepatocellular carcinoma (HCC) and address the role of IL-6 signaling in the progression of HCC. METHODS: An in vivo rat HCC model was established and IL-6 receptor (IL-6R) and downstream signaling pathway expression and activity were determined in HCC and normal liver specimens. Tumorigenic HCC cells from resected HCC samples and normal hepatocytes were then isolated and cultured in the presence and absence of recombinant human IL-6 (rhIL-6). RESULTS: HCC specimens demonstrated decreased IL-6Ralpha/gp130 expression as compared with the normal liver. In contrast, HCC samples had significantly increased IL-6 messenger RNA expression and signal transducers and activators of transcription (STAT)3 activity. Using in vitro cell cultures, we demonstrated that IL-6 stimulated STAT3 and extracellular regulated kinase (ERK) activity in both HCC cells and isolated hepatocytes. However, while STAT3 activation profiles were similar, IL-6 stimulated ERK activity in a biphasic manner in HCC cells and a monophasic, sustained ERK activation in hepatocytes. In HCC cells, a significant induction of cyclin-dependent kinase (CDK) inhibitors, p21(waf1/cip1) and p27(Kip1) occurred, an effect that was not observed in normal hepatocytes. Finally, we established that IL-6 acted to inhibit serum-stimulated DNA synthesis and cell mitogenesis in HCC cells in vitro. CONCLUSIONS: These data demonstrate altered expression of components of IL-6 signaling in HCC in vivo. IL-6 treatment of HCC cells inhibits serum-stimulated mitogenesis, possibly via differences in activation profiles of intracellular signaling pathways and their effect on CDK inhibitor expression/activity.