Multicenter Validation of Abbreviated MRI for Detecting Early-Stage Hepatocellular Carcinoma.

Background Abbreviated MRI is a proposed paradigm shift for hepatocellular carcinoma (HCC) surveillance, but data on its performance are lacking for histopathologically confirmed early-stage HCC. Purpose To evaluate the sensitivity and specificity of dynamic contrast-enhanced abbreviated MRI for early-stage HCC detection, using surgical pathologic findings as the reference standard. Materials and Methods This retrospective study was conducted at three U.S. liver transplant centers in patients with cirrhosis who underwent liver resection or transplant between January 2009 and December 2019 and standard "full" liver MRI with and without contrast enhancement within 3 months before surgery. Patients who had HCC-directed treatment before surgery were excluded. Dynamic abbreviated MRI examinations were simulated from the presurgical full MRI by selecting the coronal T2-weighted and axial three-dimensional fat-suppressed T1-weighted dynamic contrast-enhanced sequences at precontrast, late arterial, portal venous, and delayed phases. Two abdominal radiologists at each center independently interpreted the simulated abbreviated examinations with use of the Liver Imaging Reporting and Data System version 2018. Patients with any high-risk liver observations (>LR-3) were classified as positive; otherwise, they were classified as negative. With liver pathologic findings as the reference standard for the presence versus absence of early-stage HCC, the sensitivity, specificity, and their 95% CIs were calculated. Logistic regression was used to identify factors associated with correct classification. Results A total of 161 patients with early-stage HCC (median age, 62 years [IQR, 58-67 years]; 123 men) and 138 patients without HCC (median age, 55 years [IQR, 47-63 years]; 85 men) were confirmed with surgical pathologic findings. The sensitivity and specificity of abbreviated MRI were 88.2% (142 of 161 patients) (95% CI: 83.5, 92.5) and 89.1% (123 of 138 patients) (95% CI: 84.4, 93.8), respectively. Sensitivity was lower for Child-Pugh class B or C versus Child-Pugh class A cirrhosis (64.1% vs 94.2%; P < .001). Conclusion With surgical pathologic findings as the reference standard, dynamic abbreviated MRI had high sensitivity and specificity for early-stage hepatocellular carcinoma detection in patients with compensated cirrhosis but lower sensitivity in those with decompensated cirrhosis. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Kim in this issue.

Endoscopic Balloon Dilation of Strictures: Techniques, Short- and Long-Term Outcomes, and Complications.

EBD is safe and effective for the treatment of strictures. Here we describe the technique of endoscopic balloon dilation (EBD) of strictures including preprocedure considerations, indications, contraindications, and postprocedure complications. The short- and long-term outcomes of EBD including factors associated with improved outcomes are also discussed.

Computed Tomographic Angiography of the Abdomen and Pelvis in Azotemic Patients Utilizing 80-kV(p) Technique and Reduced Dose Iodinated Contrast: Comparison With Routine 120-kV(p) Technique.

OBJECTIVE: To evaluate image quality (IQ) of a reduced contrast volume, low kilovolt (peak) [kV(p)] abdominopelvic computed tomographic angiography (AP-CTA) protocol compared to a standard 120-kV(p) AP-CTA protocol. METHODS: A retrospective image analysis was performed on 103 patients with end-stage renal disease who underwent AP-CTA. Forty-nine patients were scanned at 80 kV(p) with a mean of 48 mL of contrast, and 54 patients were scanned at 120 kV(p) with a mean of 98 mL of contrast. Objective comparison of arterial attenuation, noise, and contrast-to-noise ratio was obtained, in addition to radiation dose. Subjective assessment of IQ, enhancement intensity, and image noise (IN) was scored on a 3-point scale. RESULTS: The 6-level aggregate contrast-to-noise ratio for the 80-kV(p) group was 11.8 ± 7.0, compared to 12.4 ± 4.6 in the 120-kV(p) group (P = 0.210). Radiation exposure was significantly lower in the 80-kV(p) group versus the 120-kV(p) group, as measured by average CT dose index (mGy) of 9.0 ± 3.1 and 15.8 ± 5.8 (P < 0.0001), respectively; and average dose length product (mGy × cm) of 490.0 ± 214.1 and 863.1 ± 344.4 (P < 0.0001), respectively. The 120-kV(p) technique scored better for subjective IQ (P = 0.042) and IN (P = 0.004) but not for enhancement intensity (P = 0.205). CONCLUSIONS: A 50% reduced iodinated contrast dose coupled with 80-kV(p) technique with iterative reconstruction allows for satisfactory AP-CTA studies at a 43% mean radiation dose reduction compared to a standard protocol. Negative but potentially reversible sequelae of this drop in radiation dose include increased IN and reduced subjective IQ.

Individually optimized contrast-enhanced 4D-CT for radiotherapy simulation in pancreatic ductal adenocarcinoma.

PURPOSE: To develop an individually optimized contrast-enhanced (CE) 4D-computed tomography (CT) for radiotherapy simulation in pancreatic ductal adenocarcinomas (PDA). METHODS: Ten PDA patients were enrolled. Each underwent three CT scans: a 4D-CT immediately following a CE 3D-CT and an individually optimized CE 4D-CT using test injection. Three physicians contoured the tumor and pancreatic tissues. Image quality scores, tumor volume, motion, tumor-to-pancreas contrast, and contrast-to-noise ratio (CNR) were compared in the three CTs. Interobserver variations were also evaluated in contouring the tumor using simultaneous truth and performance level estimation. RESULTS: Average image quality scores for CE 3D-CT and CE 4D-CT were comparable (4.0 and 3.8, respectively; P = 0.082), and both were significantly better than that for 4D-CT (2.6, P < 0.001). Tumor-to-pancreas contrast results were comparable in CE 3D-CT and CE 4D-CT (15.5 and 16.7 Hounsfield units (HU), respectively; P = 0.21), and the latter was significantly higher than in 4D-CT (9.2 HU, P = 0.001). Image noise in CE 3D-CT (12.5 HU) was significantly lower than in CE 4D-CT (22.1 HU, P = 0.013) and 4D-CT (19.4 HU, P = 0.009). CNRs were comparable in CE 3D-CT and CE 4D-CT (1.4 and 0.8, respectively; P = 0.42), and both were significantly better in 4D-CT (0.6, P = 0.008 and 0.014). Mean tumor volumes were significantly smaller in CE 3D-CT (29.8 cm3, P = 0.03) and CE 4D-CT (22.8 cm3, P = 0.01) than in 4D-CT (42.0 cm3). Mean tumor motion was comparable in 4D-CT and CE 4D-CT (7.2 and 6.2 mm, P = 0.17). Interobserver variations were comparable in CE 3D-CT and CE 4D-CT (Jaccard index 66.0% and 61.9%, respectively) and were worse for 4D-CT (55.6%) than CE 3D-CT. CONCLUSIONS: CE 4D-CT demonstrated characteristics comparable to CE 3D-CT, with high potential for simultaneously delineating the tumor and quantifying tumor motion with a single scan.

Long-term influence of chemotherapy on steatosis-associated advanced hepatic fibrosis.

To determine whether chemotherapy treatment at least 6 months prior to the detection of hepatic steatosis is associated with advanced hepatic fibrosis. Demographics, comorbid conditions, and laboratory data for cancer patients with hepatic steatosis were reviewed. The primary end point of this study was a low probability of fibrosis as calculated by the AST-to-platelet ratio index (APRI)-a surrogate for the absence of histologic bridging fibrosis and/or cirrhosis. Of 279 patients, 117 (41.9 %) were treated with chemotherapy and 197 (66.3 %) had a low probability of fibrosis by APRI. A smaller proportion of patients treated with chemotherapy had a low probability of hepatic fibrosis compared with untreated patients (64.1 vs. 75.3 %, p = 0.04). On multivariable analysis, chemotherapy treatment was a negative predictive factor for a low probability of fibrosis (OR 0.366 [95 % CI 0.184-0.708], p < 0.01). Among chemotherapy-treated patients, 75 (64.1 %) had a low probability of fibrosis. There were no differences in chemotherapy duration (mean 7.8 vs. 7.5 cycles) and interval from last dose to steatosis diagnosis (24.3 vs. 21.4 months) between patients with and without a low probability of fibrosis. A smaller proportion of patients treated with irinotecan or 5-fluorouracil had a low probability of fibrosis (37.3 vs. 66.7 %, p = 0.04). On multivariable analysis, irinotecan or 5-fluorouracil treatment was a negative predictive factor for low probability of fibrosis (OR 0.277 [95 % CI 0.091-0.779], p = 0.02). Prior chemotherapy treatment, especially with 5-fluorouracil or irinotecan, is a negative predictor for the absence of advanced hepatic fibrosis among patients with steatosis.

ACR appropriateness Criteria® first trimester bleeding.

Vaginal bleeding is not uncommon in the first trimester of pregnancy. Ultrasound is the foremost modality for evaluating normal development of the gestational sac and embryo and for discriminating the causes of bleeding. While correlation with quantitative ßHCG and clinical presentation is essential, sonographic criteria permit diagnosis of failed pregnancies, ectopic pregnancy, gestational trophoblastic disease and spontaneous abortion. The American College of Radiology Appropriateness Criteria guidelines have been updated to incorporate recent data. A failed pregnancy may be diagnosed when there is absence of cardiac activity in an embryo exceeding 7 mm in crown rump length or absence of an embryo when the mean sac diameter exceeds 25 mm. In a stable patient with no intrauterine pregnancy and normal adnexae, close monitoring is advised. The diagnosis of ectopic pregnancy should be based on positive findings rather than on the absence of an intrauterine sac above a threshold level of ßHCG. Following abortion, ultrasound can discriminate retained products of conception from clot and arteriovenous fistulae. The American College of Radiology Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every two years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Comparison of sagittal T2-weighted BLADE and fast spin-echo MRI of the female pelvis for motion artifact and lesion detection.

OBJECTIVE: The objective of this study was to evaluate the effectiveness of BLADE (proprietary name for periodically rotated overlapping parallel lines with enhanced reconstruction [PROPELLER] in MR systems from Siemens Healthcare) MRI compared with conventional T2-weighted fast spin-echo (FSE) MRI for reducing artifacts and improving image quality when imaging the female pelvis. MATERIALS AND METHODS: Sagittal T2-weighted BLADE and FSE examinations of the pelvis of 26 women were performed on a 1.5-T scanner. Three radiologists assessed the images for the presence of artifacts, level of anatomic detail, and overall image quality using a modified Likert scale. Scores for each radiologist and each imaging sequence were analyzed with a linear mixed model, adjusting for correlation within radiologist and within patient. A quantitative comparison was conducted to investigate signal uniformity. RESULTS: The BLADE sequence was superior for evaluation of the junctional zone (p = 0.0019), delineation of ovarian borders and depiction of follicles (p < 0.0001), and detection of fibroids (p = 0.022). Overall image quality was improved with BLADE, with fewer respiratory motion artifacts. The BLADE sequence introduced "radial" artifact that was absent from the FSE images, but this artifact did not affect image quality. Quantitative analysis revealed mean coefficients of variation for BLADE and FSE in the uterus of 21.6% and 22.5%, respectively (p = 0.36). The mean coefficients of variation were 4.6% and 6.1% in fat (p = 0.0007), indicating less variation with BLADE. The mean acquisition times for the BLADE and FSE sequences were 4 minutes 31 seconds and 3 minutes 46 seconds, respectively. CONCLUSION: Imaging of uterine junctional zone anatomy, ovaries, and fibroids was improved and artifacts were reduced with BLADE compared with FSE. Radial artifact introduced by the BLADE sequence and slightly longer imaging times needed for the BLADE sequence were offset by improved image quality.

Imaging of endometrial pathology.

The normal endometrium changes regularly with the menstrual cycle and atrophies after menopause. It is important to be aware of the normal spectrum of endometrial appearances at imaging to accurately detect and diagnose pathologic conditions. This article reviews imaging features of the normal and abnormal endometrium, and conditions which may mimic endometrial pathology. Emphasis will be on ultrasound with sonohysterography and magnetic resonance imaging as these are the imaging modalities of choice for evaluation of the endometrium. The complementary role of hysterosalpingography, computed tomography, and 18-fluorodeoxyglucose-positron emission tomography will also be discussed.

Imaging of endometrial pathology.

The normal endometrium changes regularly with the menstrual cycle and atrophies after menopause. It is important to be aware of the normal spectrum of endometrial appearances at imaging to accurately detect and diagnose pathologic conditions. This article reviews imaging features of the normal and abnormal endometrium, and conditions which may mimic endometrial pathology. Emphasis will be on ultrasound with sonohysterography and magnetic resonance imaging as these are the imaging modalities of choice for evaluation of the endometrium. The complementary role of hysterosalpingography, computed tomography, and 18-fluorodeoxyglucose-positron emission tomography will also be discussed.