Assessing Adherence to US LI-RADS Follow-up Recommendations in Vulnerable Patients Undergoing Hepatocellular Carcinoma Surveillance.

Purpose To assess adherence to the US Liver Imaging Reporting and Data System (LI-RADS) recommendations for hepatocellular carcinoma (HCC) surveillance and associated patient-level factors in a vulnerable, diverse patient sample. Materials and Methods The radiology report database was queried retrospectively for patients who underwent US LI-RADS-based surveillance examinations at a single institution between June 1, 2020, and February 28, 2021. Initial US and follow-up liver imaging were included. Sociodemographic and clinical data were captured from electronic medical records. Adherence to radiologist recommendation was defined as imaging (US, CT, or MRI) follow-up in 5-7 months for US-1, imaging follow-up in 3-6 months for US-2, and CT or MRI follow-up in 2 months for US-3. Descriptive analysis and multivariable modeling that adjusted for age, sex, race, and time since COVID-19 pandemic onset were performed. Results Among 936 patients, the mean age was 59.1 years; 531 patients (56.7%) were male and 544 (58.1%) were Asian or Pacific Islander, 91 (9.7%) were Black, 129 (13.8%) were Hispanic, 147 (15.7%) were White, and 25 (2.7%) self-reported as other race. The overall adherence rate was 38.8% (95% CI: 35.7, 41.9). The most common liver disease etiology was hepatitis B (60.6% [657 of 936 patients]); 19.7% of patients (183 of 936) had current or past substance use disorder, and 44.8% (416 of 936) smoked. At adjusted multivariable analysis, older age (odds ratio [OR], 1.20; P = .02), male sex (OR, 1.62; P = .003), hepatology clinic attendance (OR, 3.81; P < .001), and recent prior US examination (OR, 2.44; P < .001) were associated with full adherence, while current smoking (OR, 0.39; P < .001) was negatively associated. Conclusion Adherence to HCC imaging surveillance was suboptimal, despite US LI-RADS implementation. Keywords: Liver, Ultrasound, Screening, Abdomen/GI, Cirrhosis, Metabolic Disorders, Socioeconomic Issues Supplemental material is available for this article. © RSNA, 2024.

Per-patient Negative Predictive Value of the CT and MRI Liver Imaging Reporting and Data System Version 2018 Treatment Response Algorithm for Hepatocellular Carcinoma.

Background The Liver Imaging Reporting and Data System version 2018 (LI-RADS) treatment response algorithm (TRA) is a high-specificity, lower-sensitivity grading system to diagnose hepatocellular carcinoma (HCC) and recurrence after local-regional therapy. However, the emphasis on specificity can result in disease understaging, potentially leading to poorer posttransplant outcomes. Purpose To determine the negative predictive value (NPV) of pretransplant CT and MRI assessment for viable HCC on a per-patient basis using the LI-RADS TRA, considering explant pathology as the reference standard. Materials and Methods Patient records from 218 consecutive adult patients from a single institution with HCC who underwent liver transplant from January 2011 to November 2017 were retrospectively reviewed. Two readers blinded to the original report reviewed immediate (within 90 days) pretransplant imaging and characterized observations according to the LI-RADS TRA. Based on this, patients with LR-4, LR-5, or LR-TR (treatment response) viable tumors were designated as viable tumor; patients with solely LR-3 or LR-TR equivocal tumors were designated as equivocal; and patients with only LR-TR nonviable lesions were designated as no viable disease. Patients were designated as within or outside the Milan criteria. These per-patient designations were compared with the presence of viable disease at explant pathology. Fisher exact test was used to compare the differences between CT and MRI. Weighted κ values were used to calculate interreader reliability. Results Final study sample consisted of 206 patients (median age, 61 years [IQR, 57-65 years]; 157 male patients and 49 female patients). Per-patient LI-RADS TRA assessment of pretransplant imaging had an NPV of 32% (95% CI: 27, 38) and 26% (95% CI: 20, 33) (readers 1 and 2, respectively) for predicting viable disease. Seventy-five percent (reader 1) and 77% (reader 2) of patients deemed equivocal had residual tumors at explant pathology. Weighted interreader reliability was substantial (κ = 0.62). Conclusion Patient-based stratification of viable, equivocal, and nonviable disease at pretransplant CT or MRI, based on LI-RADS TRA, demonstrated low negative predictive value in excluding HCC at explant pathology. © RSNA, 2023 See also the editorial by Tamir and Tau in this issue.

Detection of fatty liver using virtual non-contrast dual-energy CT.

PURPOSE: Determine whether liver attenuation measured on dual-energy CT (DECT) virtual non-contrast examinations predicts the presence of fatty liver. METHODS: Single-institution retrospective review from 2016 to 2020 found patients with DECT and proton density fat fraction MRI (MRI PDFF) within 30 days. MRI PDFF was the reference standard for determining hepatic steatosis. Attenuation measurements from VNC and mixed 120 kVp-like images were compared to MRI PDFF in the right and left lobes. Performance of VNC was compared to measurement of the liver-spleen attenuation difference (LSAD). RESULTS: 128 patients were included (69 men, 59 women) with mean age 51.6 years (range 14-98 years). > 90% of patients received CT and MRI in the emergency department or as inpatients. Median interval between DECT and MRI PDFF was 2 days (range 0-28 days). Prevalence of fatty liver using the reference standard (MRI PDFF > 6%) was 24%. Pearson correlation coefficient between VNC and MRI- DFF was -0.64 (right) and -0.68 (left, both p < 0.0001). For LSAD, correlation was - 0.43 in both lobes (p < 0.0001). Considering MRI PDFF > 6% as diagnostic of steatosis, area under the receiver operator characteristic curve (AUC) was 0.834 and 0.872 in the right and left hepatic lobes, with an optimal threshold of 54.8 HU (right) and 52.5 HU (left), yielding sensitivity/specificity of 57%/93.9% (right) and 67.9%/90% (left). For LSAD, AUC was 0.808 (right) and 0.767 (left) with optimal sensitivity/specificity of 93.3%/57.1% (right) and 78.6%/68% (left). CONCLUSION: Attenuation measured at VNC CT was moderately correlated with liver fat content and had > 90% specificity for diagnosis of fatty liver.

Diagnosis of acute mesenteric ischemia assisted by dual-energy CT: a case report.

In this case report, dual-energy CT was critical in the diagnosis of acute mesenteric ischemia by differentiating normal contrast-enhanced bowel and hemorrhagic necrosis. Iodine map showed a segment of small bowel with minimal contrast enhancement, and virtual non-contrast imaging revealed hyperattenuating bowel. This finding changed management for the patient and prevented complications from impending bowel perforation. Histopathological analysis confirmed hemorrhagic necrosis of the bowel segment. In cases of suspected bowel ischemia, dual-energy CT can distinguish bowel wall hemorrhage from contrast enhancement and allow for accurate diagnosis.

Multi-institutional Experience with Patient Image Access Through Electronic Health Record Patient Portals.

The objective is to determine patients' utilization rate of radiology image viewing through an online patient portal and to understand its impact on radiologists. IRB approval was waived. In this two-part, multi-institutional study, patients' image viewing rate was retrospectively assessed, and radiologists were anonymously surveyed for the impact of patient imaging access on their workflow. Patient access to web-based image viewing via electronic patient portals was enabled at 3 institutions (all had open radiology reports) within the past 5 years. The number of exams viewed online was compared against the total number of viewable imaging studies. An anonymized survey was distributed to radiologists at the 3 institutions, and responses were collected over 2 months. Patients viewed 14.2% of available exams - monthly open rate varied from 7.3 to 41.0%. A total of 254 radiologists responded to the survey (response rate 32.8%); 204 were aware that patients could view images. The majority (155/204; 76.0%) felt no impact on their role as radiologists; 11.8% felt negative and 9.3% positive. The majority (63.8%) were never approached by patients. Of the 86 who were contacted, 46.5% were contacted once or twice, 46.5% 3-4 times a year, and 4.7% 3-4 times a month. Free text comments included support for healthcare transparency (71), concern for patient confusion and anxiety (45), and need for attention to radiology reports and image annotations (15). A small proportion of patients viewed their radiology images. Overall, patients' image viewing had minimal impact on radiologists. Radiologists were seldom contacted by patients. While many radiologists feel supportive, some are concerned about causing patient confusion and suggest minor workflow modifications.

Cervical Lymph Node Features Predictive of Suboptimal Adequacy During Ultrasound-Guided Fine-Needle Aspiration in Thyroid Cancer Patients.

PURPOSE: To determine the rate of cytologic and diagnostic adequacy and identify features associated with suboptimal tissue sampling in ultrasound-guided fine-needle aspiration (US-FNA) of suspected nodal disease in thyroid cancer patients. METHODS: A single-institution pathology database was queried for lymph node FNA reports in thyroid cancer patients from 2014 to 2019. Charts were reviewed for demographics, body mass index (BMI), prior thyroidectomy, cancer type, and subsequent surgery. Ultrasound images were retrospectively reviewed for location, size, depth from skin, cystic components, macrocalcification, echogenic foci, and internal vascularity score. Pathology reports were categorized as cellular and diagnostic, hypocellular/acellular but diagnostic with abnormal cells or thyroglobulin levels, or hypocellular and nondiagnostic. Correlation and multivariate regression analyses were performed. RESULTS: Initial query yielded 552 lesions in 343 subjects. Following exclusion, 377 lesions in 255 subjects were included. Mean patient age was 48.5 years (14-90), BMI 28.5, and 66.7% female and 33.3% male. The majority (95.3%) had papillary thyroid carcinoma (PTC); and 65.5% had prior thyroidectomy. 17.7% of lesions were hypocellular/acellular (suboptimal), and 5.6% nondiagnostic. Patient factors had no association (P >.05). Right-sidedness and hypovascularity were associated with hypocellularity (P <.05). Higher long/short-axis ratio and cystic foci were weakly associated. On multivariate analysis, right-sidedness (odds ratio [OR] 1.99; confidence interval [CI] 1.10-3.57) and lower vascularity score (OR 0.54; CI 0.39-0.73) were predictive of suboptimal sampling. CONCLUSION: US-FNA has high diagnostic yield and cellular sample rate. Lesion size had no effect. Right-sidedness and lower vascularity scores were predictive of suboptimal tissue. Identifying these features and expected sample adequacy rates can inform management decisions for thyroid cancer patients with cervical lymphadenopathy.

Boba sign with a twist - A variant presentation of a mature cystic teratoma complicated by torsion and rupture.

While mature cystic teratomas are relatively common ovarian neoplasms typically comprising of multiple embryologic cell types, a specific monodermal subtype involving thyroid tissue, struma ovarii, can rarely be seen. This case reviews typical imaging characteristics with MRI and ultrasound of struma ovarii and details possible complications from these masses with intraoperative and histologic correlation.

Müllerian Duct Anomalies: Role in Fertility and Pregnancy.

Müllerian duct anomalies (MDAs) have important implications for the reproductive health of female patients. In patients with both infertility and recurrent pregnancy loss, the incidence of MDAs is as high as 25%. Congenital uterine anomalies are often only part of a complex set of congenital anomalies involving the cervix, vagina, and urinary tract. Multiple classification systems for MDAs exist, each with different criteria that vary most for the diagnosis of septate uterus. Recognizing the features that guide clinical management is essential for interpretation. Identification of an MDA should prompt evaluation for associated urinary tract anomalies. In patients with infertility who seek to use assisted reproductive technologies such as intrauterine insemination, recognition of MDAs may have an affect on reproductive success, particularly in patients who have an incomplete and clinically occult septum that divides the cervix. Two-dimensional US is the first-line modality for evaluating the uterus and adnexa. Three-dimensional (3D) US or MRI may help to visualize the external uterine fundal contour and internal indentation of the endometrial cavity, which are two morphologic characteristics that are keys to the diagnosis of congenital uterine anomalies. Hysterosalpingo contrast-enhanced US may be performed in conjunction with 3D US to evaluate uterine morphologic characteristics, the endometrial cavity, and tubal patency in a single examination. MRI helps to characterize rudimentary uteri in patients with müllerian hypoplasia and allows assessment for ectopic ureters, abnormally positioned ovaries, or associated deep infiltrative endometriosis. Online supplemental material is available for this article. ©RSNA, 2021.

Role of Ultrasound for Chronic Liver Disease and Hepatocellular Carcinoma Surveillance.

Ultrasound plays a vital role in the evaluation of patients with chronic liver disease and in hepatocellular carcinoma (HCC) surveillance in populations at risk for developing HCC. Semiannual ultrasound for HCC surveillance is universally recommended by all liver societies around the world. Advanced ultrasound techniques, such as elastography and contrast-enhanced ultrasound, offer additional benefits in imaging evaluation of chronic liver disease. Major benefits of ultrasound include its high safety profile and relatively low cost.

Pearls and Pitfalls in Imaging of Pelvic Adnexal Torsion: Seven Tips to Tell It's Twisted.

Pelvic adnexal torsion is a collective term referring to twisting of an ovary, fallopian tube, or paraovarian cyst on its axis with varying degrees of vascular compromise. Although it is the fifth most common gynecologic emergency, the diagnosis is challenging and often missed due to symptoms, physical examination findings, and imaging features that are nonspecific. Delay in salvage surgery may lead to ovarian or tubal loss, dysfunction, and infertility. The tips shared herein are based on the authors' observations of key clinical and imaging features of torsion, with the intent of heightening radiologists' index of suspicion and diagnostic accuracy in a clear and memorable fashion. Clinically, severe acute pain with a known adnexal mass or of severity to elicit nausea or vomiting should raise concern. At imaging, features of ovarian edema are key to the diagnosis, including asymmetric ovarian enlargement, peripheralized follicles, adjacent free fluid, and foci of stromal hemorrhage. The converse finding of symmetric nonenlarged ovaries in a normal location with any imaging modality has a high negative predictive value for torsion, obviating the need for additional imaging. The whirlpool sign (twisted vascular pedicle), abnormal ovarian location, and uterine tilting are additional key imaging manifestations. The presence of color Doppler flow or contrast enhancement only suggests that an ovary is still viable and should not be used to exclude the diagnosis of torsion. In cases of isolated tubal or paraovarian cyst torsion, the ovaries may appear normal; therefore, recognition of this entity along with appreciation of several key imaging findings may assist with this difficult diagnosis. An invited commentary by Dighe is available online. Online supplemental material is available for this article. ©RSNA, 2021.

Ultrasound features help identify patients who can undergo noninvasive management for suspected retained products of conception: a single institutional experience.

OBJECTIVES: To evaluate ultrasound (US) features associated with successful noninvasive management for suspected retained products of conception (RPOC). METHODS: In this IRB-approved retrospective study, the radiology report database was queried for pelvic US with keywords of postpartum hemorrhage (PPH) and/or RPOC over a 2-year period. Follow-up exams, US exams without clinical follow-up, suboptimal image quality, and > 1 year from delivery or pregnancy termination were excluded. Charts were reviewed for clinical presentation and management. Two radiologists reviewed images for endometrial thickness, endometrial echogenicity, endometrial vascularity, and enhanced myometrial vascularity (EMV), as well as inner myometrial peak systolic velocity (PSV) and resistive index (RI) where available. Features were assessed for associations with management approach, and test characteristics were calculated. RESULTS: Initial query yielded 196 exams, and 48 were excluded. A total of 148 patients were included. Mean age was 34.2 years (21-47), and mean time from delivery or pregnancy termination was 40.4 days (0-223). 81 (55%) underwent noninvasive management: 72 (48%) expectant and 9 (6%) medical. 67 (45%) underwent invasive management: 60 (41%) surgical and 7 (5%) uterine artery embolization. There was substantial inter-reader agreement for assessment of EMV (K = 0.78) and endometrial vascularity (K = 0.72). Thin endometrial stripe, avascular endometrium, and absence of EMV were associated with successful noninvasive management (p < 0.05). Thin endometrium (< 10 mm) had specificity (90%), PPV (88%), and likelihood ratio (5.91) in predicting successful noninvasive management. CONCLUSION: Endometrial thickness < 10 mm, avascular endometrium, and absence of EMV are the sonographic features associated with successful noninvasive management for PPH or suspected RPOC.

Placental thickness correlates with placenta accreta spectrum (PAS) disorder in women with placenta previa.

OBJECTIVE: To evaluate the association of placental thickness with placenta accreta spectrum disorder in placenta previa. METHODS: In this IRB-approved, retrospective study, ultrasound (US) reports were retrospectively queried for keyword previa. US performed closest to mid-gestation were included. Three measurements were performed at the thickest portion of the placenta on longitudinal transabdominal images. Operative reports and surgical pathology were used as the reference standard. Statistical analysis was performed using unpaired T-tests and receiver operating curve (ROC) analysis. RESULTS: Sixty-five patients with placenta previa were included: 38 with PAS disorder and 27 without PAS disorder, clinically or pathologically. 38/38 (100%) patients of PAS group and 16/27 (59.3%) patients of non-PAS group had history of prior cesarean section. The average placental thickness was 4.3 cm (range 1.8 cm to 7.8 cm) for PAS group and 3.0 cm (range 0.6 cm to 5.3 cm) for non-PAS group (p < 0.001). Placental thickness in patients without PAS disorder and history of prior cesarean section was 3.1 (± 1.1) cm. This was statistically different from patients who had history of prior cesarean section with PAS diagnosis (4.3 cm, P<0.01). Using ROC analysis, a threshold measurement of 4.5 cm leads to sensitivity of 50% and specificity of 96%. CONCLUSION: Our results demonstrate that among women with placenta previa, increased placental thickness at lower uterine segment correlates with placenta accreta spectrum disorder. A threshold of 4.5 cm can be useful for screening patients with placenta previa and risks factors for PAS.

Ultrasound Liver Imaging Reporting and Data System (US LI-RADS): An Overview with Technical and Practical Applications.

The Ultrasound Liver Imaging Reporting and Data System (US LI-RADS), introduced in 2017 by the American College of Radiology, standardizes the technique, interpretation, and reporting of screening and surveillance ultrasounds intended to detect hepatocellular carcinoma in high-risk patients. These include patients with cirrhosis of any cause as well as subsets of patients with chronic hepatitis B viral infection. The US LI-RADS scheme is composed of an ultrasound category and a visualization score: ultrasound categories define the exam as negative, subthreshold, or positive and direct next steps in management; visualization scores denote the expected sensitivity of the exam, based on adequacy of liver visualization with ultrasound. Since its introduction, multiple institutions across the United States have implemented US LI-RADS. This review includes a background of hepatocellular carcinoma and US LI-RADS, definition of screening/surveillance population, recommendations and tips for technique, interpretation, and reporting, and preliminary outcomes analysis.

Traumatic testicular rupture: Multimodality imaging with intraoperative correlate.

Traumatic testicular rupture is a rare yet serious condition most commonly seen in penetrating trauma victims (e.g. gunshot wounds or motorcycle collisions) that requires immediate surgical management given its potential complications of hypogonadism and infertility. While ultrasound is the most established modality for diagnosing testicular rupture, trauma patients are usually first evaluated with a trauma protocol computed tomography (CT) exam including the chest, abdomen, and pelvis upon presentation, so it is important to recognize CT findings of testicular injury. We present a novel case in which the suspicion for testicular injury was initially raised based upon CT findings of scrotal hematoma/fluid. These findings were then further characterized with ultrasound and confirmed at surgery. In this case, we provide intraoperative imaging that corresponds clearly to findings seen on both CT and ultrasound.

How common are traumatic injuries to the epididymis? A study of prevalence, imaging appearance, and management implications.

PURPOSE: To evaluate the prevalence of epididymal injuries with scrotal trauma, review imaging appearance, clinical management, and outcomes. METHODS: In this retrospective study, the radiology report database was queried for scrotal ultrasounds containing keywords pertaining to trauma, from 1998 to 2019. Exams with no clinically documented trauma, exams with trauma > 1 year ago, and duplicate exams were excluded. Chart review was conducted for age, trauma mechanism, time interval between trauma and ultrasound, signs of infection, and clinical management. Reports were reviewed to record the presence of scrotal injury, traumatic epididymitis, or epididymal hematoma. Cases with epididymal injury underwent image review. Descriptive statistics, Fisher's exact test, and Mann-Whitney's U test were performed to evaluate for associations between clinical parameters and epididymal injury. RESULTS: Initial search yielded 385 exams. A total of 103 exams met inclusion criteria. Trauma mechanisms included straddle injury (35%), blunt scrotal trauma by ball or other object (29%), assault (28%), penetrating injury (4%), and fall (3%). Sixty-eight patients (66%) had scrotal injury on imaging. Twenty-six (25%) had epididymal injury. Thirteen were isolated to the epididymis, and 13 had associated testicular or extra-testicular findings. There were 12 cases of traumatic epididymitis and 14 epididymal hematomas. All epididymal injuries were managed non-operatively. A total of 7 were prescribed antibiotics, including 1 subject who otherwise had no evidence of infection. CONCLUSION: Epididymal injury is encountered in 25% of scrotal ultrasounds for trauma evaluation. Traumatic epididymitis can be seen in 12%. It is important for radiologists to recognize this entity, as it can be mistaken for infection.

Acute diverticulitis: Key features for guiding clinical management.

Diverticular disease of the colon and small bowel is an important cause of pathology leading to emergency department visits and urgent gastrointestinal surgery. CT is a highly sensitive and specific modality for the diagnosis of acute diverticulitis and its complications as well as for the exclusion of alternate causes of pathology. Ultrasound, MRI and virtual CT colonoscopy have important adjunct roles for screening and workup of complications in specific patient populations. While diverticular disease most commonly involves the descending and sigmoid colon, it can also affect the proximal colon and small bowel. Acute diverticulitis may be categorized as uncomplicated or complicated according to the degree of inflammatory changes and related complications it induces, although some degree of overlap exists in clinical practice. Uncomplicated diverticulitis is classically characterized by localized inflammation surrounding a diverticulum ranging from wall thickening and phlegmonous change to the development of small, localized pericolic abscesses. Complicated forms of disease manifest with larger pericolic and distant abscesses, fistulae to adjacent organs, perforation, and peritonitis. Recurrent episodes of diverticulitis may lead to muscular hypertrophy of the bowel wall and luminal narrowing, potentially leading to bowel obstruction. Several imaging features may help to differentiate diverticulitis from colonic malignancy, however this remains a diagnostic imaging challenge that often requires further evaluation with colonoscopy. In this review, we discuss the pathophysiology and key imaging features of acute diverticulitis and its complications. We explore both common and uncommon presentations of the disease involving the colon and small bowel, acute and chronic manifestations of disease, and pitfalls to recognize when imaging alone may be insufficient to distinguish benign from malignant.

Implementation and design of artificial intelligence in abdominal imaging.

Artificial intelligence is a technique that holds promise for helping radiologists improve the care of our patients. At the same time, implementation decisions we make now can have a long-lasting effect on patient outcomes. In the following article, we discuss four areas with unique considerations for implementation of AI: bias, trust, risk, and design. In each section, we highlight applications of AI to abdominal imaging and prostate cancer specifically.