A Multicenter Assessment of Interreader Reliability of LI-RADS Version 2018 for MRI and CT.

Background Various limitations have impacted research evaluating reader agreement for Liver Imaging Reporting and Data System (LI-RADS). Purpose To assess reader agreement of LI-RADS in an international multicenter multireader setting using scrollable images. Materials and Methods This retrospective study used deidentified clinical multiphase CT and MRI and reports with at least one untreated observation from six institutions and three countries; only qualifying examinations were submitted. Examination dates were October 2017 to August 2018 at the coordinating center. One untreated observation per examination was randomly selected using observation identifiers, and its clinically assigned features were extracted from the report. The corresponding LI-RADS version 2018 category was computed as a rescored clinical read. Each examination was randomly assigned to two of 43 research readers who independently scored the observation. Agreement for an ordinal modified four-category LI-RADS scale (LR-1, definitely benign; LR-2, probably benign; LR-3, intermediate probability of malignancy; LR-4, probably hepatocellular carcinoma [HCC]; LR-5, definitely HCC; LR-M, probably malignant but not HCC specific; and LR-TIV, tumor in vein) was computed using intraclass correlation coefficients (ICCs). Agreement was also computed for dichotomized malignancy (LR-4, LR-5, LR-M, and LR-TIV), LR-5, and LR-M. Agreement was compared between research-versus-research reads and research-versus-clinical reads. Results The study population consisted of 484 patients (mean age, 62 years ± 10 [SD]; 156 women; 93 CT examinations, 391 MRI examinations). ICCs for ordinal LI-RADS, dichotomized malignancy, LR-5, and LR-M were 0.68 (95% CI: 0.61, 0.73), 0.63 (95% CI: 0.55, 0.70), 0.58 (95% CI: 0.50, 0.66), and 0.46 (95% CI: 0.31, 0.61) respectively. Research-versus-research reader agreement was higher than research-versus-clinical agreement for modified four-category LI-RADS (ICC, 0.68 vs 0.62, respectively; P = .03) and for dichotomized malignancy (ICC, 0.63 vs 0.53, respectively; P = .005), but not for LR-5 (P = .14) or LR-M (P = .94). Conclusion There was moderate agreement for LI-RADS version 2018 overall. For some comparisons, research-versus-research reader agreement was higher than research-versus-clinical reader agreement, indicating differences between the clinical and research environments that warrant further study. © RSNA, 2023 Supplemental material is available for this article. See also the editorials by Johnson and Galgano and Smith in this issue.

How to Use LI-RADS to Report Liver CT and MRI Observations.

Primary liver cancer is the fourth leading cause of cancer-related deaths worldwide, with hepatocellular carcinoma (HCC) comprising the vast majority of primary liver malignancies. Imaging plays a central role in HCC diagnosis and management. As a result, the content and structure of radiology reports are of utmost importance in guiding clinical management. The Liver Imaging Reporting and Data System (LI-RADS) provides guidance for standardized reporting of liver observations in patients who are at risk for HCC. LI-RADS standardized reporting intends to inform patient treatment and facilitate multidisciplinary communication and decisions, taking into consideration individual clinical factors. Depending on the context, observations may be reported individually, in aggregate, or as a combination of both. LI-RADS provides two templates for reporting liver observations: in a single continuous paragraph or in a structured format with keywords and imaging findings. The authors clarify terminology that is pertinent to reporting, highlight the benefits of structured reports, discuss the applicability of LI-RADS for liver CT and MRI, review the elements of a standardized LI-RADS report, provide guidance on the description of LI-RADS observations exemplified with two case-based reporting templates, illustrate relevant imaging findings and components to be included when reporting specific clinical scenarios, and discuss future directions. An invited commentary by Yano is available online. Online supplemental material is available for this article. Work of the U.S. Government published under an exclusive license with the RSNA.

CT Scans Obtained for Nonpulmonary Indications: Associated Respiratory Findings of COVID-19.

Background Atypical manifestations of coronavirus disease 2019 (COVID-19) are being encountered as the pandemic unfolds, leading to non-chest CT scans that may uncover unsuspected pulmonary disease. Purpose To investigate patients with primary nonrespiratory symptoms who underwent CT of the abdomen or pelvis or CT of the cervical spine or neck with unsuspected findings highly suspicious for pulmonary COVID-19. Materials and Methods This retrospective study from March 10, 2020, to April 6, 2020, involved three institutions, two in a region considered a hot spot (area of high prevalence) for COVID-19. Patients without known COVID-19 were included who presented to the emergency department (ED) with primary nonrespiratory (gastrointestinal or neurologic) symptoms, had lung parenchymal findings suspicious for COVID-19 at non-chest CT but not concurrent chest CT, and underwent COVID-19 testing in the ED. Group 1 patients had reverse transcription polymerase chain reaction (RT-PCR) results obtained before CT scan reading (COVID-19 suspected on presentation); group 2 had RT-PCR results obtained after CT scans were read (COVID-19 not suspected). Presentation and imaging findings were compared, and outcomes were evaluated. Descriptive statistics and Fisher exact tests were used for analysis. Results Group 1 comprised 62 patients (31 men, 31 women; mean age, 67 years ±17 [standard deviation]), and group 2 comprised 57 patients (28 men, 29 women; mean age, 63 years ± 16). Cough and fever were more common in group 1 (37 of 62 [60%] and 29 of 62 [47%], respectively) than in group 2 (nine of 57 [16%] and 12 of 57 [21%], respectively), with no significant difference in the remaining symptoms. There were 101 CT scans of the abdomen or pelvis and 18 CT scans of the cervical spine or neck. In group 1, non-chest CT findings provided the initial evidence of COVID-19-related pneumonia in 32 of 62 (52%) patients. In group 2, the evidence was found in 44 of 57 (77%) patients. Overall, the most common CT findings were ground-glass opacity (114 of 119, 96%) and consolidation (47 of 119, 40%). Major interventions (vasopressor medication or intubation) were required for 29 of 119 (24%) patients, and 27 of 119 (23%) died. Patients who underwent CT of the cervical spine or neck had worse outcomes than those who underwent abdominal or pelvic CT (P = .01). Conclusion In a substantial percentage of patients with primary nonrespiratory symptoms who underwent non-chest CT, CT provided evidence of coronavirus disease 2019-related pneumonia. © RSNA, 2020.

Diagnostic Performance of LI-RADS Version 2018, LI-RADS Version 2017, and OPTN Criteria for Hepatocellular Carcinoma.

OBJECTIVE. Liver Imaging Reporting and Data System (LI-RADS) was updated in 2018 (LI-RADS version 2018 [LI-RADSv2018]) to facilitate integration into the American Association for the Study of Liver Diseases 2018 clinical practice guidelines and involved changes in LR-5 categorization and threshold growth definitions. There are also differences between the criteria for LI-RADSv2018 LR-5 category and the criteria for Organ Procurement and Transplantation Network (OPTN) class 5. The objective of our study was to compare the diagnostic performances of LI-RADSv2018, LI-RADS version 2017 (LI-RADSv2017), and OPTN criteria for diagnosing hepatocellular carcinoma (HCC) on MRI. MATERIALS AND METHODS. In this retrospective study, 122 patients with 159 observations were included who met LI-RADS criteria for at risk for HCC and had at least one hepatic observation on MRI performed between January 1, 2015, and January 1, 2018 and who had histopathology results (n = 104) or follow-up imaging (n = 55) as reference standards. Three abdominal radiologists assigned categories independently and in consensus using LI-RADSv2017, LI-RADSv2018, and OPTN criteria. Diagnostic performance was compared among the guidelines with a generalized estimating equation. RESULTS. Fourteen of 159 (8.8%) observations were assigned a different category according to LI-RADSv2018 compared with LI-RADSv2017. Eight of 31 (25.8%) LR-4 observations using v2017 were recategorized as LR-5 using v2018, and all eight were HCC. Six of 31 (19.4%) LR-4 observations based on v2017 were recategorized as LR-3 using v2018, and all six were non-HCCs. Seven of 114 (6.1%) observations not meeting OPTN class 5 criteria were LR-5 using v2018, and all seven were HCC. Sensitivity for HCC of LR-5 and LR-TIV+5 (i.e., LR-TIV [tumor in vein] definitely due to HCC) categories based on v2018 was significantly higher than that based on v2017 (63.9% vs 55.2%, respectively; p = 0.008) without a difference in specificity (97.3% vs 97.3%; p = 1.00). Sensitivity of LR-5 and LR-TIV+5 in LI-RADSv2018 was significantly higher than the sensitivity of class 5 in OPTN criteria (63.9% vs 53.6%; p = 0.004) without a difference in specificity (97.3% vs 97.3%; p = 1.00). Reader agreement was moderate for overall LIRADSv2017 and LI-RADSv2018 categories (κ = 0.504 and 0.561, respectively); substantial for LR-5 and LR-TIV+5 categories as diagnostic of HCC versus other categories for both v2017 and v2018 (κ = 0.758 and 0.802, respectively); and substantial for OPTN class 5 criteria (κ = 0.756). CONCLUSION. The diagnostic performance of LI-RADSv2018 is higher, with higher sensitivity and similar specificity, than the diagnostic performance of LI-RADSv2017 and OPTN criteria for HCC.

Peripheral arterial occlusion due to COVID-19: CT angiography findings of nine patients.

BACKGROUND: Reports have indicated an association of large vessel peripheral arterial occlusion in the setting of Coronavirus Disease 2019 (COVID-19). While prior investigations have mostly focused on venous or cerebral arterial occlusions, we examined patients presenting exclusively with peripheral arterial extremity occlusions to investigate for any predisposing factors in this subset of COVID-19 patients. MATERIALS AND METHODS: This is a retrospective study of COVID-19 patients with peripheral arterial occlusions presenting to a multi-hospital health care system in New York City between February 1st, 2020 and April 30th, 2020. Patient data and computed tomography angiography (CTA) exams in this subset were then collected and analyzed. RESULTS: For the months of February, March, and April 2020, we identified 9 patients (ages 37-93 yrs) at our health care system who underwent extremity CTA for large vessel upper or lower extremity arterial occlusion and were diagnosed with COVID-19. Patient medical histories and clinical parameters were evaluated to identify common risk factors including obesity, hypertension, hyperlipidemia, and diabetes. Patients presented with increased inflammatory markers including ferritin, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) as well as increased D-dimer. CONCLUSION: Our findings suggest patients with COVID-19 and comorbidities presenting with elevated inflammatory markers and D-dimer may be at increased risk of large vessel peripheral arterial occlusion.

Semi-Automated 3D Volumetric Renal Measurements in Polycystic Kidney Disease Using b0-Images-A Feasibility Study.

Autosomal dominant polycystic kidney disease (ADPKD) eventually leads to end stage renal disease (ESRD) with an increase in size and number of cysts over time. Progression to ESRD has previously been shown to correlate with total kidney volume (TKV). An accurate and relatively simple method to perform measurement of TKV has been difficult to develop. We propose a semi-automated approach of calculating TKV inclusive of all cysts in ADPKD patients based on b0 images relatively quickly without requiring any calculations or additional MRI time. Our purpose is to evaluate the reliability and reproducibility of our method by raters of various training levels within the environment of an advanced 3D viewer. Thirty patients were retrospectively identified who had DWI performed as part of 1.5T MRI renal examination. Right and left TKVs were calculated by five radiologists of various training levels. Interrater reliability (IRR) was estimated by computing the intraclass correlation (ICC) for all raters. ICC values calculated for TKV measurements between the five raters were 0.989 (95% CI = (0.981, 0.994), p < 0.01) for the right and 0.961 (95% CI = (0.936, 0.979), p < 0.01) for the left. Our method shows excellent intraclass correlation between raters, allowing for excellent interrater reliability.

Analysis of Different Levels of Structured Reporting in Knee Magnetic Resonance Imaging.

RATIONALE AND OBJECTIVES: The aim of this study is to investigate the most appropriate knee MRI report template that not only provides structure and consistency, but also allows enough narrative freedom for the logical organization of findings and improved communication with the orthopedic referral base. MATERIALS AND METHODS: Three fictitious knee MRI reports were created using templates with different levels of structuring: unstructured free text (FT), structured with headers (SH), and highly structured and itemized (SI). These were then distributed to clinicians in the orthopedics department at all levels of training along with a survey with numerical scoring questions on report readability, usefulness, and quality. Statistical analysis was used to evaluate the data. RESULTS: Fifty-three surveys were completed with responses from residents, attendings, and physician assistants. The structured format with headers had statistically significant (p value <0.001) higher mean rank score in readability, usefulness, and quality parameters compared to the unstructured FT and highly SI report templates. Most clinicians (83%) found the structured format with headers to be the most coherent report. Conversely, 53% found the unstructured FT and 43% found the highly SI templates to be the most disjointed. CONCLUSION: Based on responses to surveys of knee MRI report templates, our results show that our orthopedic clinicians prefer some level of structure in the reports but not the rigorous itemization of anatomic tissues. A "middle ground" reporting structure which includes headers for different anatomic compartments and allows for grouping of relevant pathology, is shown to be the preferred format.

Utility of dynamic MRA in the evaluation of male erectile dysfunction.

PURPOSE: To assess the efficacy of time-resolved MR angiography (MRA) in evaluating penile vasculature in patients with clinically suspected vascular anomalies contributing to their erectile dysfunction correlating with penile doppler ultrasound (PDUS) findings and clinical outcomes after surgical intervention. METHODS: Men (n = 26) with signs of early vascular shunting on PDUS underwent time-resolved, contrast-enhanced (0.1 mMol/kg gadobutrol at 1 ml/s followed by saline flush) 3-dimensional spoiled gradient echo T1-weighted MRA sequence performed over 3 min with 4.6 s frame rate after intracavernosal injection of an erectogenic agent. Additional T1- and T2-weighted sequences were performed for anatomic co-localization and tissue characterization. MRA images were evaluated for early filling of draining veins as well as arteriovenous malformations and fistulas and correlated with findings at surgery. RESULTS: 29 MRA examinations on 26 patients (mean age 39 years) demonstrated abnormal early venous drainage (n = 22) as well as diminutive/delayed cavernosal enhancement (n = 3), incomplete tumescence (n = 2), and combined arterial inflow/venous outflow disease (n = 1). The MRA had a concordance of 85.2% at determining the presence, or lack thereof of a shunt/AVM when compared to PDUS. CONCLUSIONS: Time-resolved MRA allows for both temporal and spatial resolution with visualization of both arterial and venous abnormalities which may be suggested with a screening PDUS examination. This technique allows us to provide detailed anatomic information prior to any surgical intervention.

CT/MR LI-RADS 2018: clinical implications and management recommendations.

Unique among solid organ tumors, hepatocellular carcinoma (HCC), may be diagnosed by imaging alone, without the need for biopsy. The Liver Imaging Reporting and Data System (LI-RADS) was developed to provide high-specificity diagnosis of HCC based on imaging while also standardizing the assessment and reporting of the entire spectrum of lesions and pseudolesions encountered in patients at risk for this malignancy. In this pictorial review, we discuss management recommendations associated with CT/MR LI-RADS observations. We emphasize the rationale for the recommendations and the role of multidisciplinary management discussion, and we provide a framework for standardized reporting. Management of patients who undergo ultrasound (US) for screening and surveillance or those who undergo diagnostic contrast-enhanced ultrasound (CEUS) is beyond the scope of this paper.

Patients Want to Meet With Imaging Experts.

PURPOSE: The evolving health care landscape demands a multidisciplinary approach to care and increased emphasis on patient engagement. Radiologists may play an important role in this respect, by improving patient agency and understanding through direct patient interaction. The purpose of this study is to assess patient preferences and perceptions regarding direct communication with radiologists, focusing on a medically underserved demographic. METHODS: Our institutional review board approved this HIPAA-compliant study. English- and/or Spanish-speaking adults undergoing imaging studies across two tertiary-care hospitals and a busy outpatient center were surveyed over a consecutive two-month period, to assess knowledge of the role of a radiologist, interest in, and perceived benefits of reviewing examination results with imaging experts. RESULTS: A total of 628 surveys were completed: 20% of total respondents accurately identified the role of radiologists; 28% identified radiologists as doctors. A total of 68% of respondents expressed an interest in receiving imaging results immediately, or whenever results became available, regardless of when referring physicians received results. An interest in reviewing imaging results with an expert was indicated by 81% of respondents; 88% anticipated that reviewing imaging results with an expert would be beneficial. Although 58% of respondents indicated that they might be willing to pay out of pocket for such a service, 50% selected $0 when asked to indicate an amount. CONCLUSIONS: Although most patients do not know the role of radiologists, they want immediate results, and perceive value in consulting directly with imaging experts.

Adult Embryonal Sarcoma of the Liver: Management of a Massive Liver Tumor.

Undifferentiated embryonal sarcomas of the liver are extremely rare cases in adults. We report the case of a 30-year-old male who presented with early satiety and abdominal pain due to a massive tumor originating from the left liver and occupying the entire epigastrium. The patient underwent bland embolization in an attempt to decrease the size of the tumor. He then underwent a formal left hepatectomy with resection of liver segments 2, 3, and 4. Extrahepatic inflow control of the portal vein and hepatic artery was performed prior to parenchymal transection. No Pringle maneuver was required. Pathology analysis showed a 45 cm tumor consistent with an undifferentiated embryonal sarcoma and negative microscopic margins. The epidemiology, treatment, and prognosis of this unusual cancer presentation are reviewed.

Renal sarcoid: Pseudotumoral radiologic manifestations and pathologic correlation.

Sarcoidosis has a wide variety of radiologic manifestations. However, lesions that mimic tumors are rare presentations of this systemic disorder. Differentiating sarcoid granulomas from malignancy is critical, as management and prognosis for these two entities are drastically different. Therefore, it is imperative to be cognizant of the various radiologic appearances of pseudotumoral renal sarcoid. We report a case of a 61-year-old man with recently diagnosed prostate cancer and pulmonary sarcoidosis discovered on staging CT who presented with pseudotumoral renal sarcoid mimicking malignancy.