Abdominal pelvic CT findings compared between COVID-19 positive and COVID-19 negative patients in the emergency department setting.

PURPOSE: Manifestations of COVID-19 are primarily respiratory based, however, gastrointestinal symptoms are now recognized as an important component of the disease. The purpose of this study is to evaluate differences in abdominal pelvic CT findings in the emergency department by COVID-19 test result. METHODS: This retrospective study identified patients tested by PCR for COVID-19 infection who underwent abdominal pelvic CT scan in the ED across an academic health system from March 15 to April 15, 2020. Radiology reports were reviewed for the presence of ground glass opacity in the lungs and acute abdominal pathology. A subset of patients with acute abdominal pathology were identified with inflammatory pathology in organs with high ACE2 receptor expression including bowel, pancreas, urinary bladder, and kidney. CT findings for COVID positive versus negative patients were compared with Chi-square test. RESULTS: 597 patients tested by PCR for COVID-19 infection underwent abdominal pelvic CT scan, 44% were COVID-19 positive. COVID-19 positive patients demonstrated significantly more ground glass opacity at the lung bases, 65.1%, (222/341) versus 12.4% (33/266), p < 0.001), and significantly less acute abdominal findings, 23.8% (81/341) versus 45.5% (121/266), p ≤ 0.001). When abdominal pathology was present, COVID-19 positive patients had higher rate of inflammatory pathology 58% (47/81) versus 29.8% (36/121). CONCLUSIONS: In patients undergoing abdominopelvic CT from the ED, COVID-19 positive patients are more likely to have ground glass opacities at the lung bases and less likely to have acute abdominal pathology compared with COVID-19 negative patients. Further, COVID-19 positive patients are more likely to have inflammation of organs with high expression of ACE2 receptors than other types of acute abdominal pathology.

Role of CT in the management of recurrent ovarian cancer.

OBJECTIVE: The purpose of this study was to evaluate the potential role of preoperative CT in patients with recurrent ovarian cancer who undergo secondary cytoreductive surgery. MATERIALS AND METHODS: Preoperative CT examinations of 36 consecutive patients (age range, 30-75 years; mean age, 55 years) were reviewed retrospectively. Patients had recurrent ovarian cancer and secondary cytoreduction within a mean CT-surgery interval of 22 days (range, 2-69 days). The CT findings recorded were upper abdominal metastases (e.g., peritoneal carcinomatosis; perihepatic, perisplenic, gastrohepatic or gastrosplenic ligaments; gallbladder fossa; falciform ligament; lesser sac), lymphadenopathy (above or below the renal hilum), liver metastasis, large- and small-bowel obstruction, hydronephrosis, ascites, and the presence of a pelvic mass. CT findings and cancer antigen-125 (CA-125) levels were correlated with surgical resectability. RESULTS: At surgery, tumors in 27 patients were optimally debulked (residual disease of

Ovarian malignancies.

Ovarian cancer is the second most common pelvic tumor and the leading cause of death from a gynecologic malignancy. MRI plays a strategic role in patient care for initial evaluation and treatment planning in patients with ovarian cancer. This article reviews the pathologic classification and characteristic findings on MRI of ovarian malignancies, patterns of tumor spread and staging, and the utility of cross-sectional imaging prior to primary and secondary to cytoreproductive surgery.

Utility of sonography for small hepatic lesions found on computed tomography in patients with cancer.

OBJECTIVE: To assess the performance of sonography in evaluating small indeterminate liver lesions detected on computed tomography in patients with cancer. METHODS: Radiology database review from January 1, 1998, to August 4, 2000, identified 76 patients with 124 indeterminate hepatic lesions smaller than 1.5 cm on computed tomography who had abdominal sonography within 3 months. Sonographic reports and images were reviewed to assess whether lesions were referenced or specifically sought and to verify lesion correspondence, detection, and characterization. The validity of sonographic characterization was determined by histopathologic examination or follow-up imaging (mean time to follow up, 17 months; range, 6.5-38.8 months). RESULTS: Sixty (48%) of 124 indeterminate lesions were evident on sonography. Detection improved when lesions were specifically sought and lesion size was greater than 0.5 cm. Forty (66%) of 61 lesions were detected when the radiologist referenced the preceding computed tomography versus 20 (32%) of 63 lesions when the computed tomographic findings were not referenced (P = .0004). Fifty-one (67%) of 76 lesions measuring 0.6 to 1.5 cm were detected on sonography versus 9 (19%) of 48 lesions measuring 0.1 to 0.5 cm. Lesion size (P < .0001) and body habitus (P = .02) were significant factors influencing lesion detection. Sonography characterized 56 (93%) of 60 detected lesions (33 cysts, 18 solid lesions/metastases, and 5 hemangiomas). Sonographic diagnoses were supported in 42 (93%) of 45 lesions by follow-up imaging (37 of 40) or histopathologic examination (5 of 5). CONCLUSIONS: Sonography may be useful in cancer patients with average body habitus to characterize small (0.6- to 1.5-cm) indeterminate liver lesions detected on computed tomography.

Subcutaneous nodules at the injection site of low-molecular-weight heparin: a mimic of metastatic disease at CT.

PURPOSE: To describe the appearance and prevalence of subcutaneous nodules in the anterior abdominal wall seen at CT in cancer patients receiving subcutaneous injections of low-molecular-weight heparin (LMWH). METHODS: CT examinations were reviewed in 426 patients receiving subcutaneous abdominal wall injections of LMWH for the presence of nodules. Nodules were evaluated for contour, maximal diameter, CT attenuation, and presence of hazy changes or air in the surrounding fat. RESULTS: Fourteen (3%) of the 426 patients had nodules attributable to subcutaneous injections of LMWH. Findings included poorly defined borders (100%), adjacent hazy soft tissue changes (100%), adjacent air (57%), and a mean CT attenuation of -4.4 HU (range: -50-40 HU). Three (0.7%) of 426 patients had nodules caused by metastatic disease. One (33%) nodule had poorly defined borders, two (67%) had surrounding hazy changes, one (33%) had air in adjacent tissue, and there was a mean CT attenuation of 44 HU (range: 14-140 HU). One (0.2%) patient had a subcutaneous nodule of uncertain etiology. CONCLUSION: Patients receiving subcutaneous injections of LMWH may develop nodules at the injection sites. Such nodules can resemble metastatic tumor deposits at CT, and careful correlation with clinical history and growth trends of metastatic deposits elsewhere in the patient is needed to avoid misdiagnosis.

Detection and characterization of adnexal masses.

The main challenge to the radiologist is to differentiate benign from malignant adnexal masses. Both US and MRI perform well for prediction of benignity. There is less specificity for diagnosis of malignancy but features, such as papillary projections, thickened septations, and internal vascularity within nodules, aid in this differentiation. The combination of morphology and Doppler characteristics provide the most accurate US diagnosis. For sonographically indeterminate masses, MRI is useful for additional lesion characterization. Analysis of T1- and T2-weighted signal intensities for benign-appearing lesions with the addition of fat saturation for high signal on T1-weighted sequences may lead to an exact diagnosis or a narrow differential. For cases considered suspicious by TVUS, more specific diagnosis by MRI may obviate the need for surgery or otherwise change management by identification of benign etiology.