Description: Autoimmune hepatitis (AIH) is an uncommon, chronic inflammatory, and relapsing liver disease of unknown origin that may lead to liver cirrhosis, hepatocellular carcinoma, liver transplantation, or death. AIH occurs in all age groups and races but can frequently manifest as acute fulminant hepatitis. Clinical presentation of AIH can have features similar to primary sclerosing cholangitis (PSC) and primary biliary cirrhosis (PBC), and these diseases may coexist leading to overlap syndromes. Although histological diagnosis is necessary, imaging features often can demonstrate characteristics that may be helpful to distinguish these diseases. Imaging features of AIH are those of chronic liver disease, and imaging plays important role in detection of complications and ruling out other possible causes of chronic liver disease. Emerging techniques such as elastography provide non-invasive options for diagnosis of significant fibrosis and cirrhosis during clinical follow-up as well as assessment of response to treatment. In this study, we will describe imaging findings in AIH and overlap syndromes.

Description: Purpose To assess the frequency of blood glucose level higher than 150 mg/dL in non-diabetic patients presenting for FDG PET. Methods We reviewed the electronic medical record (EMR) of all lymphoma patients who had at least one FDG PET/CT from July 1, 2014 through June 30, 2015. We extracted the blood glucose level at the time of the FDG PET during this 1-year time period and any previous PET scans these patients had. Patients’ diabetic status was determined from EMR. Results One hundred seventeen patients with 574 scans were included: 91 non-diabetic with 429 scans and 26 diabetic patients with 145 scans. Blood glucose level ranged from 44 to 259 mg/dL: 44 to 144 mg/dL in non-diabetic patients and 73 to 259 mg/dL in diabetic patients. There was no non-diabetic patient with a glucose level higher than 150 mg/dL at any occasion. Only one scan was performed with 144 mg/dL of glucose. All other scans were performed with a glucose level less than 140 mg/dL. There were nine diabetic patients with glucose level less than 150 mg/dL prior to all of their scans and 17 diabetic patients with a glucose level higher than 150 mg/dL prior to PET at least on one occasion. Conclusions In all non-diabetic patients, blood glucose level was below the lower limit of the recommended range prior to all their FDG PET scans while this was not the case in diabetic patients. We conclude that measuring blood glucose level prior to FDG PET may be limited to diabetic patients.

Description: Non-alcoholic fatty liver disease is the most common cause of chronic liver disease and affects nearly one-third of US population. With the increasing trend of obesity in the population, associated fatty change in the liver will be a common feature observed in imaging studies. Fatty liver causes changes in liver parenchyma appearance on imaging modalities including ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) and may affect the imaging characteristics of focal liver lesions (FLLs). The imaging characteristics of FLLs were classically described in a non-fatty liver. In addition, focal fatty change and focal fat sparing may also simulate FLLs. Knowledge of characteristic patterns of fatty change in the liver (diffuse, geographical, focal, subcapsular, and perivascular) and their impact on the detection and characterization of FLL is therefore important. In general, fatty change may improve detection of FLLs on MRI using fat suppression sequences, but may reduce sensitivity on a single-phase (portal venous) CT and conventional ultrasound. In patients with fatty liver, MRI is generally superior to ultrasound and CT for detection and characterization of FLL. In this pictorial essay, we describe the imaging patterns of fatty change in the liver and its effect on detection and characterization of FLLs on ultrasound, CT, MRI, and PET.

Description: Focal small bowel lesions present a diagnostic challenge for both the radiologist and gastroenterologist. Both the detection and characterization of small bowel masses have greatly improved with the advent of multidetector CT enterography (MD-CTE). As such, MD-CTE is increasingly utilized in the workup of occult gastrointestinal bleeding. In this article, we review the spectrum of focal small bowel masses with pathologic correlation. Adenocarcinoma, the most common primary small bowel malignancy, presents as a focal irregular mass occasionally with circumferential extension leading to obstruction. Small bowel carcinoid tumors most commonly arise in the ileum and are characterized by avid enhancement and marked desmoplastic response of metastatic lesions. Aneurysmal dilatation of small bowel is pathognomonic for lymphoma and secondary findings of lymphadenopathy and splenomegaly should be sought. Benign small bowel masses such as leiomyoma and adenoma may be responsible for occult gastrointestinal bleeding. However, primary vascular lesions of the small bowel remain the most common cause for occult small bowel gastrointestinal bleeding. The arterial phase of contrast obtained with CTE aids in recognition of the vascular nature of these lesions. Systemic conditions such as Peutz–Jeghers syndrome and Crohn’s disease may be suggested by the presence of multiple small bowel lesions. Lastly, potential pitfalls such as ingested material should be considered when faced with focal small bowel masses.

Description: Purpose Image-guided percutaneous pelvic procedures often play an important role in the management of women with gynecologic cancers. The purpose of this study is to evaluate the utilization of and indications for these procedures, and quantify their impact on patient management. Methods IRB-approved retrospective record review of percutaneous pelvic procedures requested by gynecologic oncology, 2005 to 2015. Descriptive statistics and logistic regression were performed. Results 392 pelvic procedures, including fluid aspiration, core biopsy, and fine needle aspiration, were performed in 225 women. Procedures were performed under sonographic guidance (303/392, 77.30%), CT guidance (87/392, 22.19%), or both (2/392, 0.51%). Pathology results included: no specimen sent (157/392, 40.05%), new cancer diagnosis (55/392, 14.03%), recurrence or metastasis of known primary cancer (107/392, 27.30%), benign tissue (67/392, 17.09%), and nondiagnostic (6/392, 1.53%). In terms of management, some procedures led to oncologic surgery, radiation, or chemotherapy (158/392, 40.31%), cessation of oncologic treatment (36/392, 9.18%), or treatment of infection (10/392, 2.55%). Many procedures were therapeutic (178/392, 45.41%), while a minority were performed for genomics (1/392, 0.26%) or did not impact clinical management (9/392, 2.30%). The number of procedures per year increased over time during the period of data collection. Date of service was a significant positive predictor of a purely therapeutic procedure (OR 1.69 [95 % CI 1.44–1.98], p  〈 0.0001) and a significant negative predictor of a malignant diagnosis (OR 0.72 [95 % CI 0.64–0.81], p  〈 0.0001), for each year later in the 10-year cycle. Conclusion In this single institution study, we identified a trend toward increased utilization of image-guided percutaneous pelvic interventions in women with gynecologic cancers. The case mix has shifted over the past 10 years, with procedures for symptom management constituting a larger proportion and diagnostic procedures constituting a smaller proportion of procedures over time.

Description: Purpose The purpose of the study was to assess the diagnostic performance of qualitative and quantitative diffusion-weighted imaging (DWI) in differentiating benign from malignant ovarian and uterine masses. Materials and methods Institutional review board approval was obtained for this HIPAA-compliant retrospective study, with waiver of informed consent. DWI MRIs of 222 women acquired over 1.5 years were evaluated. Reference standard was pathology or follow-up imaging. For qualitative assessment, two radiologists independently reviewed DWI and apparent diffusion coefficient (ADC) images for diffusion restriction. Differences were resolved by consensus. For quantitative assessment, a single reader measured ADC values. Readers were blinded to the reference standard. Results 222 lesions, 121 ovarian (99 benign and 22 malignant) and 101 uterine (54 benign and 47 malignant), were included. Final diagnosis was established with pathology in 129 (58%) or with imaging follow-up in 93 (42%). Mean (range) follow-up interval was 27 (13–48) months. Qualitative assessment yielded sensitivity (ratio, 95% CI), specificity, PPV and NPV of 100% (22/22, 85–100), 68% (68/99, 58–76), 41% (22/54, 27–54), and 100% (68/68, 94–100) for ovarian and 94% (44/47, 83–98), 91% (49/54, 80–96), 90% (44/49, 78–95) and 94% (49/52, 84–98) for uterine malignancies. ADC (mean ± SD) between benign ovarian [(1.11 ± 0.76) × 10 −3  mm 2 /s] vs. malignant [(0.71 ± 0.26) × 10 −3  mm 2 /s] lesions was significantly different ( p  〈 0.001). ADC cutoff value of 1.55 × 10 −3  mm 2 /s for ovarian lesions resulted in 99.9% confidence for the absence of malignancy. ADC (mean ± SD) of benign uterine [(0.64 ± 0.38) × 10 −3  mm 2 /s] vs. malignant [(0.68 ± 0.19) × 10 −3 mm 2 /s] lesions was not significantly different ( P  〈 0.54). Conclusion Quantitative and qualitative DWI assessment can be used to confidently characterize a subset of ovarian lesions as benign. With uterine lesions, although DWI is useful in differentiating benign from malignant lesions, the technique does not allow for definitive quantitative characterization.

Description: Neuroendocrine (NE) neoplasms of the genitourinary (GU) tract in adults are rare tumors with distinct histopathology and variable biological behavior and imaging findings. They may be primary or metastatic in origin. The spectrum of primary GU tract NE neoplasms includes carcinoid, small cell carcinoma, large cell NE carcinoma, and paraganglioma. The tumors commonly show positivity to specific immunohistochemical markers and characteristic dense-core granules at the ultra-structural level. Although imaging findings are nonspecific and accurate differentiation from the more common malignancies of the individual organs is not possible, cross-sectional imaging modalities play an important role in the diagnosis, staging, and surveillance of these tumors. Somatostatin receptor scintigraphy (octreotide scan) may be useful in the detection and treatment of metastatic disease in select patients. Knowledge of the various NE tumors of the adult GU tract and familiarity with their pathological and imaging findings permit optimal patient management.

Description: Complete hydatidiform mole is a common cause of gestational bleeding of the first trimester, commonly assessed by ultrasound. It represents an abnormal proliferation of trophoblastic tissue, with no fetal formation, just hydropic villi. These abnormal villi seen in ultrasound are compared to a “bunch of grapes,” a classic description of this disease.