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Background: The effect of differing post-contrast phases on CT body composition measurements is not yet known. Methods: A fully automated AI-based body composition analysis using DAFS was performed on a retrospective cohort of 278 subjects undergoing pre-treatment triple-phase CT for pancreatic intraductal papillary mucinous neoplasm. The CT contrast phases included noncontrast (NON), arterial (ART), and venous (VEN) phases. The software selected a single axial CT image at mid-L3 on each phase for body compartment segmentation. The areas (cm2) were calculated for skeletal muscle (SM), intermuscular adipose tissue (IMAT), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT). The mean Hounsfield units of skeletal muscle (SMHU) within the segmented regions were calculated. Bland–Altman and Chi Square analyses were performed. Results: SM-NON had a lower percentage of bias [LOA] than SM-ART, −0.7 [−7.6, 6.2], and SM-VEN, −0.3 [−7.6, 7.0]; VAT-NON had a higher percentage of bias than ART, 3.4 [−18.2, 25.0], and VEN, 5.8 [−15.0, 26.6]; and this value was lower for SAT-NON than ART, −0.4 [−14.9, 14.2], and VEN, −0.5 [−14.3, 13.4]; and higher for IMAT-NON than ART, 5.9 [−17.9, 29.7], and VEN, 9.5 [−17.0, 36.1]. The bias in SMHU NON [LOA] was lower than that in ART, −3.8 HU [−9.8, 2.1], and VEN, −7.8 HU [−14.8, −0.8]. Conclusions: IV contrast affects the voxel HU of fat and muscle, impacting CT analysis of body composition. We noted a relatively smaller bias in the SM, VAT, and SAT areas across the contrast phases. However, SMHU and IMAT experienced larger bias. During threshold risk stratification for CT-based measurements of SMHU and IMAT, the IV contrast phase should be taken into consideration. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: This study aimed to determine the frequency of hepatic contour abnormalities and signs of portal hypertension at serial CT in patients receiving chemotherapy for breast cancer metastatic to the liver. Materials and Methods: We retrospectively identified 91 women with breast cancer metastatic to the liver who received chemotherapy and underwent serial CT at our institution between 1998 and 2002. Two readers independently categorized hepatic contour abnormalities on the final CT examination as none, limited retraction, widespread retraction, or diffuse nodularity. Readers also recorded the development of hepatic atrophy or enlargement, ascites, portosystemic collateral veins, and splenomegaly. Interpretative discrepancies were resolved by consensus. Portal hypertension was defined as the presence of at least two of the following CT signs: simple ascites, portosystemic collateral veins, and splenomegaly. Results: After a median follow-up interval of 15 months (range, 1–46), hepatic contour abnormalities were seen in 68 of 91 patients (75%) and consisted of limited retraction (n=42), widespread retraction (n=10), or diffuse nodularity (n=16). Portal hypertension was found in 1 of 23 patients without contour abnormalities, in 1 of 42 patients with limited retraction, in none of 10 patients with widespread retraction, and in 6 of 16 patients with diffuse nodularity (P<.01). Conclusion: Hepatic contour abnormalities commonly develop at serial CT in patients undergoing chemotherapy for breast cancer metastatic to the liver and may be accompanied by signs of portal hypertension; the latter are particularly, but not exclusively, associated with the development of diffuse hepatic nodularity. [Copyright &y& Elsevier]

Abstract: Objective: To determine the relative accuracy of CT or MR imaging in the detection of inoperable tumor sites prior to cytoreductive surgery in a large series of patients with newly diagnosed primary epithelial ovarian cancer. Methods: One hundred thirty-seven women with newly diagnosed primary epithelial ovarian cancer underwent CT (n = 91) or MR imaging (n = 46) prior to cytoreductive surgery. The following imaging criteria were used to identify inoperable tumor sites: (1) peritoneal implants greater than 2 cm in maximum diameter in the porta hepatis, intersegmental fissure, gall bladder fossa, subphrenic space, gastrohepatic ligament, gastrosplenic ligament, lesser sac, or root of the small bowel mesentery; (2) retroperitoneal adenopathy greater than 2 cm in maximum diameter above the renal hila; (3) hepatic metastases or abdominal wall invasion. Imaging results were compared with operability at surgery. Results: Cytoreductive surgery was suboptimal in 21 of the 137 (15%) patients. Sixteen of these patients had inoperable tumor on preoperative imaging, while one additional patient had apparently inoperable tumor on imaging but was optimally debulked at surgery. The sensitivity, specificity, positive predictive value, and negative predictive value of preoperative imaging for the prediction of suboptimal debulking were 76% (16/21), 99% (115/116), 94% (16/17), and 96% (115/120), respectively. CT and MR imaging were equally effective (P = 1.0) in the detection of inoperable tumor. Conclusion: Preoperative CT and MR imaging are equally accurate in the detection of inoperable tumor and the prediction of suboptimal debulking in newly diagnosed epithelial ovarian cancer. This suggests imaging may help select patients who might be more appropriately managed by neoadjuvant chemotherapy. [Copyright &y& Elsevier]

Because liver fibrosis can be treated, it is important to diagnose liver fibrosis noninvasively and monitor response to treatment. Although ultrasound (grayscale and Doppler) can diagnose cirrhosis, it does so unreliably using morphologic and sonographic features and cannot diagnose the earlier, treatable stages of hepatic fibrosis. Transient elastography, ultrasound elastography with acoustic radiation force impulse, and MR elastography are modalities that can assess for hepatic fibrosis. Although all international organizations recommend ultrasound for screening for hepatocellular carcinoma, ultrasound is particularly limited for identifying hepatocellular carcinoma in patients with obesity, nonalcoholic fatty liver disease, and nodular cirrhotic livers. In these patients, as well as patients who are on the liver transplant wait list, ultrasound is so limited that consideration can be made for screening for hepatocellular carcinoma with either MRI or multiphase CT. Additionally, patients who have been previously diagnosed with and treated for hepatocellular carcinoma require continued surveillance for recurrent hepatocellular carcinoma. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment. [ABSTRACT FROM AUTHOR]

Abstract: We retrospectively reviewed the records of 153 patients with breast cancer undergoing serial abdominal computed tomography (CT). During a median follow-up of 40 months, 2 (1.4%) of 153 patients developed bilateral hydronephrosis in the absence of radiologically visible obstructing pathology. Surgery confirmed malignant infiltration of the ureters by metastatic lobular carcinoma in both patients, suggesting that new unexplained bilateral hydronephrosis on serial CT in patients with breast cancer is likely to reflect infiltrative retroperitoneal involvement of the ureters by metastatic lobular carcinoma. [Copyright &y& Elsevier]

Abstract: Two patients with renal cell carcinoma and one patient with metastasis to the kidney from colorectal cancer are reported because all three cases manifested at computed tomography (CT) as a renal mass invading the pelvicaliceal system and radiologically simulating transitional cell carcinoma. Recognition that the CT finding of a renal mass with invasion of the pelvicaliceal system is not always indicative of a transitional cell carcinoma broadens the differential diagnosis in this setting and might potentially alter the diagnostic and therapeutic approach. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To evaluate whether supine or prone positioning improves pelvicalyceal and ureteral opacification at multi-detector row computed tomographic (CT) urography. Methods: We retrospectively reviewed the CT urograms of 114 consecutive patients performed for hematuria. Using a “split-bolus” technique, all patients were imaged 340 s after the injection of intravenous contrast, 63 in the supine and 51 in the prone position. The right and left pelvicalyceal systems and ureters were divided into six segments: anterior calyces, posterior calyces, renal pelvis, proximal ureter, mid ureter, and distal ureter. Two readers rated the opacification of each segment in consensus on a four-point scale from 0 (no opacification) to 3 (excellent opacification). Opacification scores were compared between supine and prone CT urograms using generalized estimating equation models. Results: Supine positioning resulted in higher opacification scores of the renal pelvis and the posterior calyces than prone positioning (P<.01). Prone positioning resulted in higher opacification scores of the anterior calyces only (P<.01). No significant differences were seen between the supine and prone opacification scores for the proximal, mid, or distal ureters (P values all >.5). Conclusion: Supine positioning results in overall greater opacification of the pelvicalyceal system compared to prone positioning at CT urography. [Copyright &y& Elsevier]

Abstract: Purpose: To determine if small hypoattenuating renal masses can be characterized as simple cysts or renal cell carcinomas on contrast-enhanced computed tomography (CT). Materials and methods: We retrospectively identified 20 small (≤1.5 cm) hypoattenuating renal masses seen on contrast enhanced CT, consisting of 14 simple cysts and six renal cell carcinomas. Three independent readers recorded subjective visual impression (five-point scale from 1=definitely fluid to 5=definitely solid), CT attenuation, border (well circumscribed or ill defined), and shape (ovoid or irregular) for each lesion. Results: The overall area under the receiver operator characteristic curves for subjective visual impression, CT attenuation, border, and shape were 0.97, 0.82, 0.59, and 0.55, respectively. Using dichotomized ratings (1–2=cyst and 3–5=carcinoma), subjective impression had a sensitivity and specificity of 100% and 79–100%, respectively, for the diagnosis of renal cell carcinoma. Using a threshold of 50 Hounsfield Units (HU) or more, CT attenuation had a sensitivity and specificity of 100% and 43–64%, respectively. Conclusion: Small hypoattenuating renal masses can be characterized with reasonable accuracy by subjective impression and CT attenuation; lesions that appear solid on visual inspection or have an attenuation value of 50 HU or more are likely to be renal cell carcinoma. [Copyright &y& Elsevier]