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This study provides an updated overview of the clinical characteristics of post-traumatic trigeminal neuropathic pain (PTNP) resulting from dental procedures or facial trauma, addressing its etiology, prevalence, evaluation, management, and prognosis. PTNP arises from injury to the trigeminal nerve, which governs sensory and motor functions in the maxillofacial region. The prevalence and characteristics of PTNP vary considerably across studies, with a reported prevalence ranging from 1.55% to 13%. The predominant causative factors are dental procedures, particularly third molar removal and implant placement. While gender distribution varies, a trend towards higher incidence in females is observed, particularly within the 40-60-year age group. Anatomically, the mandibular nerve is frequently involved. PTNP presents with a spectrum of symptoms ranging from tingling sensations to severe pain. Diagnostic challenges arise due to the lack of standardized criteria and potential overlap with focal neuralgia, necessitating comprehensive evaluation. Misdiagnosis can lead to prolonged patient suffering and unnecessary interventions. Successful management hinges on prompt diagnosis and interdisciplinary collaboration, with early intervention crucial in mitigating progression to chronic pain. Although nerve recovery post-trauma is challenging, preventive measures through accurate evaluation and treatment are paramount. Management strategies for PTNP include non-invasive and surgical interventions, with non-invasive approaches encompassing systemic and local pharmacological management. This narrative review aims to enhance uniformity in PTNP evaluation and treatment approaches, ultimately improving patient care and outcomes.
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PURPOSE: This study aimed to evaluate the effectiveness of using the severity of hyperechoic pancreas (HP) observed on preoperative ultrasonography (US) as a predictor of clinically relevant postoperative pancreatic fistula (CR-POPF). METHODS: A retrospective study was conducted with 94 patients who underwent pancreatectomy between April 2006 and March 2021. The severity of HP on US was classified into two categories (normal to mild vs. moderate to severe [obvious HP]). Multiple preoperative and intraoperative parameters were analyzed to predict CR-POPF. RESULTS: Out of the 94 patients, CR-POPF occurred in 21 (22%) patients, and obvious HP was observed in 30 (32%). Univariate analysis revealed that moderate to severe HP (obvious HP) was significantly associated with an increased incidence of CR-POPF (P<0.001). Factors such as the absence of pancreatitis, a small main pancreatic duct (<3 mm), intraoperative soft pancreas, increased body mass index, and lower pancreatic attenuation and attenuation index were also associated with CR-POPF (all P<0.05). Multivariate analysis showed that obvious HP and soft pancreatic texture were independent predictors of CR-POPF, with odds ratios of 11.53 (P=0.001) and 14.12 (P=0.003), respectively. The combination of obvious HP and soft pancreatic texture provided the most accurate prediction for CR-POPF. CONCLUSION: The severity of HP, as observed on preoperative US, was significantly associated with CR-POPF. Severe HP may serve as a clinically useful predictor of POPF, especially when evaluated alongside the intraoperative pancreatic texture.
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BACKGROUND: Recurrence of uterine cervical cancer is common and often shows a dismal prognosis. Local recurrence usually manifests as solid soft tissue lesions and has rarely been reported to have cystic lesions. CASE PRESENTATION: Herein, we report a case of recurrent uterine cervical cancer with initial manifestation as a hemorrhagic cyst, assessed using strain sonoelastography, CT, and MRI. CONCLUSION: Although cystic recurrence is uncommon, newly detected simple or complex cystic lesions should be closely monitored.
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Background The 2017 international consensus guidelines for intraductal papillary mucinous neoplasm (IPMN) of the pancreas are widely used. Purpose To evaluate the interobserver agreement and diagnostic performance of MRI assessment in predicting the malignant potential of IPMN according to radiologists' experience. Materials and Methods This multicenter retrospective study included 100 patients with pathologically proven pancreatic IPMN (77 patients with surgery, 23 patients with biopsy) who underwent contrast-enhanced MRI between 2016 and 2021. Eight post-fellowship radiologists (four more-experienced [8-20 years] and four less-experienced [1-4 years] reviewers) evaluated MRI for high-risk stigmata and worrisome features identified by the most recent 2017 guidelines. Interobserver agreement was determined using Fleiss κ statistics according to radiologist experience. The diagnostic performance for malignant IPMN was assessed using receiver operating characteristic curve analysis. Results Among 100 patients (mean age, 66 years ± 10 [SD]; 57 men), 52 (52%) had malignant IPMN. For high-risk stigmata, interobserver agreement was substantial for main pancreatic duct size of at least 10 mm (κ = 0.78; 95% CI: 0.75, 0.82), enhancing mural nodule of at least 5 mm (κ = 0.70: 95% CI: 0.66, 0.74), and at least one high-risk stigmata (κ = 0.73: 95% CI: 0.69, 0.76). The worrisome features showed fair to substantial interobserver agreement (κ range, 0.22-0.80). More-experienced reviewers demonstrated better agreement in the assessment of at least one high-risk stigmata than less-experienced reviewers (κ = 0.77 vs κ = 0.69, P < .001). The overall diagnostic performance of each reviewer was good for the prediction of malignant pancreatic IPMN (area under the receiver operating characteristic curve [AUC] range, 0.77-0.84; median AUC, 0.82), with substantial agreement (κ = 0.76). Conclusion The 2017 international consensus guidelines enabled good diagnostic performance and substantial interobserver agreement for high-risk stigmata but not worrisome features on the evaluation of the malignant pancreatic IPMN using MRI. Agreement tended to be better among more-experienced reviewers than among less-experienced reviewers. © RSNA, 2023 Supplemental material is available for this article.
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Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Masculino , Humanos , Idoso , Variações Dependentes do Observador , Estudos Retrospectivos , Imageamento por Ressonância MagnéticaRESUMO
Ascaris lumbricoides causes one of the most common soil-transmitted helminthiases globally. The worms mostly infect the human small intestine and elicit negligible or nonspecific symptoms, but there are reports of extraintestinal ectopic ascariasis. We describe a rare case of biliary ascariasis mistaken for biliary stent in a 72-year-old female patient with a history of liver resection. She visited our outpatient clinic complaining of right upper quadrant pain and fever for the past week. She had previously undergone left lateral sectionectomy for recurrent biliary and intrahepatic duct stones 2 years ago. Besides mildly elevated gamma-glutamyl transferase levels, her liver function tests were normal. Magnetic resonance cholangiopancreatography revealed a linear filling defect closely resembling an internal stent from the common bile duct to the right intrahepatic bile duct. A live female A. lumbricoides adult worm was removed by endoscopic retrograde cholangiopancreatography (ERCP). Despite a significant decrease of the ascariasis prevalence in Korea, cases of biliary ascariasis are still occasionally reported. In this study, a additional case of biliary ascariasis, which was radiologically misdiagnosed as the biliary stent, was described in a hepatic resection patient by the worm recovery with ERCP in Korea.
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Ascaríase , Doenças Biliares , Humanos , Adulto , Animais , Feminino , Idoso , Ascaríase/diagnóstico , Doenças Biliares/diagnóstico , Ascaris lumbricoides , Fígado , StentsRESUMO
[This corrects the article DOI: 10.3389/fpsyg.2022.1050435.].
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AIM: The application of compressed sensing (CS) has enabled breath-hold 3D-MRCP with a shorter acquisition time in clinical practice. INTRODUCTION: To compare the image quality of breath-hold (BH) and respiratory-triggered (RT) 3D-MRCP with or without CS application in the same study population. METHODS: In this retrospective study, from February to July 2020, a total of 98 consecutive patients underwent four different acquisition types of 3D-MRCP.; 1) BH MRCP with the generalized autocalibrating partially parallel acquisition (GRAPPA) (BH-GRAPPA), 2) RT-GRAPPA-MRCP, 3) RT-CS-MRCP and 4) BH-CS-MRCP. Relative contrast of common bile duct, 5-scale visibility score of biliary pancreatic ducts, 3-scale artifact score and 5-scale overall image quality score were evaluated by two abdominal radiologists. RESULTS: Relative contrast value was significantly higher in BH-CS or RT-CS than in RT-GRAPPA (0.90 ± 0.057 and 0.89 ± 0.079, respectively, vs. 0.82 ± 0.071, p < 0.01) or BH-GRAPPA (vs. 0.77 ± 0.080, p < 0.01). The area affected by artifact was significantly lower in BH-CS among 4 MRCPs (p < 0.08). Overall image quality score in BH-CS was significantly higher than BH-GRAPPA (3.40 vs. 2.71, p < 0.01). There were no significant differences between RT-GRAPPA and BH-CS (vs. 3.13, p = 0.67) in overall image quality. CONCLUSION: In this study, our results revealed BH-CS had higher relative contrast and comparable or superior image quality among four MRCP sequences.
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OBJECTIVE: Chronic stress in adolescence may affect brain maturation and predispose individuals to psychiatric disorders in adulthood. However, whether chronic juvenile stress influences vulnerability to nonpsychiatric brain injuries, such as traumatic brain injury (TBI), remains unclear. Therefore, we hypothesized that juvenile stress-related neuronal circuit disturbances could aggravate brain damage following TBI in adulthood. METHODS: For chronic stress, we used an unpredictable chronic mild stress (UCMS) procedure for 5 weeks in adolescent mice. This was followed by a controlled cortical impact (CCI) injury to evaluate the influence of chronic juvenile stress on brain damage progression following TBI in adult mice. Mice underwent UCMS alone, UCMS followed by CCI, CCI alone, or sham operation. We characterized neurobehavioral deficits (Barnes maze, open field, and light-dark tests), neuroinflammation (ionized calcium-binding adapter molecule 1 [Iba-1], glial fibrillary acidic protein [GFAP], and neuron-specific nuclear protein [NeuN] immunoreactivity), and apoptosis (B-cell lymp [Bcl-2], Bcl-2-associated X protein [Bax], and procaspase-3 immunoreactivity). RESULTS: Following CCI, mice exposed to UCMS showed decreased spatial learning and memory in the Barnes maze test compared with unstressed mice. A significant increase in Iba-1, GFAP, and Bax/Bcl-2 immunostaining levels was observed in the mice exposed to UCMS followed by CCI compared with the CCI-only mice. In contrast, a significant decrease in NeuN immunostaining levels was observed in the UCMS with CCI group compared with the CCI alone group. CONCLUSION: Chronic stress in a juvenile mouse model aggravates neurobehavioral impairments and potentiates glial reactivity, neuronal injury, and apoptosis following moderate-to-severe TBI that occurs in adulthood. The present study suggests that juvenile chronic stress may influence poor outcomes following TBI in later adulthood.
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BACKGROUND: Benign lesions cause ovarian torsion more commonly than malignant ovarian tumors. Further, Krukenberg tumors have rarely been reported to cause ovarian torsion. CASE PRESENTATION: Herein, we present the case of a patient with an incidentally discovered ovarian mass, which was finally diagnosed as a Krukenberg tumor accompanying ovarian torsion with primary stomach cancer. We further review the clinical, imaging, and histological features of Krukenberg tumors. CONCLUSION: Radiologists should be aware of Krukenberg tumors that may present with ovarian torsion.
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Tumor de Krukenberg , Neoplasias Ovarianas , Neoplasias Gástricas , Feminino , Humanos , Tumor de Krukenberg/diagnóstico por imagem , Tumor de Krukenberg/patologia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/diagnóstico por imagem , Torção Ovariana/diagnóstico , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/diagnóstico por imagem , Diagnóstico DiferencialRESUMO
BACKGROUND: Angiolipoma is a benign neoplasm mainly composed of adipose tissue and proliferating blood vessels and is relatively rare in the gastrointestinal tract. And among them, gastric angiolipomas are extremely rare and tend to be small. CASE PRESENTATION: We report the clinical and imaging features of a patient with a huge angiolipoma in the stomach and an episode of hematemesis and melena, caused by the ulceration of the gastric mucosa overlying the gastric subepithelial angiolipoma revealed by the endoscopic evaluation. The patient was anemic, and the anemia resolved after local surgical resection of the tumor. We also reviewed the imaging and histological features of the presenting gastric angiolipoma. CONCLUSION: Radiologists should be aware of this rare benign gastric tumor that may present with gastrointestinal hemorrhage.
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Angiolipoma , Neoplasias Gástricas , Humanos , Angiolipoma/complicações , Angiolipoma/diagnóstico por imagem , Angiolipoma/cirurgia , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/etiologia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgiaRESUMO
The aim of this study was to evaluate cortical bone formation on the mandibular condyle using cone-beam computed tomography (CBCT) in asymptomatic adolescents and young adults and to evaluate the relationship between age and sex. CBCT images that can evaluate the shape of the mandibular condyle were selected from asymptomatic patients aged 13−25. The degree of cortication on the mandibular condyle (CMC) was evaluated using CBCT images reconstructed in the axial, sagittal, and coronal planes. CBCT data of 829 patients (413 males, 416 females) were selected and then the left and right images of all patients were acquired; consequently, a total of 1658 temporomandibular joint-related images were evaluated in this study. The degree of CMC was correlated with age in men and women (p < 0.05). The frequency of CMC 0 disappeared in woman aged 20 years and in men aged 21 years. Cortical bone formation of the mandibular condyle was completed at age 22 years in women and 24 years in men. The degrees of cortical bone formation of the mandibular condyle between men and women showed significant differences between the ages of 15−19 and 22 years. This difference can be interpreted as a different mandible growth period between the sexes.
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Renomedullary interstitial cell tumors are often incidentally identified either upon autopsy or kidney resection for other reasons. However, rare renomedullary interstitial cell tumor cases resulting in a clinical symptomatic mass have been reported. We present a case of renomedullary interstitial cell tumor that was manifested as an incidentally detected renal mass and mimicked renal cell carcinoma on the imaging features.
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The purpose of this study is to evaluate the usefulness of virtual unenhanced (VUE) and low keV virtual monochromatic images (VMI) for diagnosing viable hepatocellular carcinomas (HCC) after transarterial chemoembolization (TACE). This retrospective study included 53 patients with suspected viable HCC after TACE who underwent multiphasic liver computed tomography including true unenhanced (TUE) phase and conventional (CV) enhanced phases on a dual-energy scanner. VUE images, 40 keV and 55 keV VMIs of enhanced phases were reconstructed using dual-energy computed tomography data. For every patient, six combination image sets (TUE-CV; TUE-55; TUE-40; VUE-CV; VUE-55; VUE-40) were evaluated by two readers and compared with the reference standard.There was no statistically significant difference (Pâ >â .05) in sensitivity or specificity among all image combinations. In most combinations, interobserver agreements were almost perfect. The diagnostic odds ratio showed a higher trend in combinations with conventional images. Currently, with regards to diagnostic performance, liver computed tomography including TUE and CV enhanced phases is recommended for tumor surveillance after TACE because VUE and VMIs do not have a distinct advantage compared to conventional images.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Tomografia Computadorizada por Raios X/métodosRESUMO
RATIONALE: Desmoid fibromatosis is a rare benign tumor, but due to its rarity and diverse clinical course, treatment guidelines have not been established. However, since a good prognosis can be expected, an accurate diagnosis and appropriate treatment are required. We describe a rare case of desmoid fibromatosis on young female that presented as huge abdominal mass. PATIENTS CONCERNS: A 28-year-old female with left upper abdominal pain 1 month ago was referred. DIAGNOSES: Abdominal computed tomography and magnetic resonance imaging revealed a heterogeneous soft tissue mass approximately 29â ×â 17 cm in size in the left abdomen with abdominal wall invasion and pathological fracture in costochondral junction of the left 8th to 10th ribs. INTERVENTIONS: Surgical resection was performed. OUTCOMES: 33â ×â 23â ×â 6 cm sized tumorous mass showed proliferation of bland fibromatosis and myofibroblast with nuclear ß-catenin expression on pathological examination. Desmoid fibromatosis arising from intra-abdominal soft tissue with ribs and pericardium invasion was diagnosed. LESSONS: The mainstay of treatment of symptomatic desmoid fibromatosis is surgical resection, and in the case of abdominal tumor, it can be more dangerous when it invades adjacent organ. We report a case that required additionally multidisciplinary approach for surgery and postoperative treatment of huge abdominal desmoid tumor which infiltrate bone and pericardium beyond abdominal cavity.
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Fibroma , Fibromatose Agressiva , Adulto , Feminino , Fibromatose Agressiva/diagnóstico por imagem , Fibromatose Agressiva/cirurgia , Humanos , Pericárdio/patologia , Costelas/patologia , beta CateninaRESUMO
PURPOSE This study aimed to assess the agreement between liver stiffness (LS) values obtained by the gradient-recalled echo (GRE) magnetic resonance elastography (MRE) and spin-echo echo-planar imaging (SE-EPI) MRE with those of transient elastography (TE), respectively. METHODS We retrospectively included 48 participants who underwent liver MRE with both GRE and SE-EPI sequences in the same session and also TE within 1 year. We obtained LS values for MRE by drawing free-hand region of interest, and TE was performed using a FibroScan device. We assessed the relationship between the mean LS values obtained by each MRE sequence and TE using the correlation coefficients and Bland-Altman plots, respectively. We also compared LS values and technical failure rates of measured values from MRE between SE-EPI and GRE sequences using the paired t-test and McNemar's test. The MRE failure was defined as the absence of pixel value with a confidence index above 95%. RESULTS The LS values from SE-EPI and GRE sequences strongly correlated with those from TE (GRE; r = 0.73, P < .001 vs. SE-EPI; r = 0.79, P < .001). In addition, the LS values from the 2 MRE sequences showed excellent relationship (intraclass correlation coefficient, 0.94 [0.89-0.97], P < .001). The LS values from SE-EPI and GRE MRE were not significantly different (4.14 kPa vs. 3.88 kPa, P = .19). Furthermore, the technical success rate of SE-EPI MRE was superior to that of GRE (100% vs. 83.8%, P = .031). CONCLUSION The measured LS values obtained using TE correlated strongly with those obtained using GRE and SE-EPI MRE techniques, even though SE-EPI-MRE resulted a higher technical success rate than GRE-MRE. Therefore, we believe that TE, GRE, and SE-EPI MR elastography techniques may complement each other according to the appropriate individual situation.
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Técnicas de Imagem por Elasticidade , Imagem Ecoplanar/métodos , Técnicas de Imagem por Elasticidade/métodos , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
OBJECTIVES: To evaluate the diagnostic accuracy of perfluorobutane contrast-enhanced ultrasonography (CEUS) for hepatocellular carcinoma (HCC) and to explore how accuracy can be improved compared to conventional diagnostic criteria in at-risk patients. METHODS: A total of 123 hepatic nodules (≥ 1 cm) from 123 at-risk patients who underwent perfluorobutane CEUS between 2013 and 2020 at three institutions were retrospectively analyzed. Ninety-three percent of subjects had pathological results, except benign lesions stable in follow-up images. We evaluated presence of arterial phase hyperenhancement (APHE), washout time and degree, and Kupffer phase (KP) defects. KP defects are defined as hypoenhancing lesions relative to the liver in KP. HCC was diagnosed in two ways: (1) Liver Imaging Reporting and Data System (LI-RADS) criteria defined as APHE and late (≥ 60 s)/mild washout, and (2) APHE and Kupffer (AK) criteria defined as APHE and KP defect. We explored grayscale features that cause misdiagnosis of HCC and reflected in the adjustment. Diagnostic performance was compared using McNemar's test. RESULTS: There were 77 HCCs, 15 non-HCC malignancies, and 31 benign lesions. An ill-defined margin without hypoechoic halo on grayscale applied as a finding that did not suggest HCC. Regarding diagnosis of HCC, sensitivity of AK criteria (83.1%; 95% confidence interval [CI]: 72.9-90.7%) was higher than that of LI-RADS criteria (75.3%; 95% CI: 64.2-84.4%; p = 0.041). Specificity was 91.3% (95% CI: 79.2-97.6%) in both groups. CONCLUSION: On perfluorobutane CEUS, diagnostic criteria for HCC using KP defect with adjustment by grayscale findings had higher diagnostic performance than conventional criteria without losing specificity. KEY POINTS: ⢠Applying Kupffer phase defect instead of late/mild washout and adjusting with grayscale findings can improve the diagnostic performance of perfluorobutane-enhanced US for HCC. ⢠Adjustment with ill-defined margins without a hypoechoic halo for features unlikely to be HCC decreases false positives for HCC diagnosis using the perfluorobutane-enhanced US. ⢠After adjustment with grayscale findings, the sensitivity and accuracy of the APHE and Kupffer criteria were higher than those of the LI-RADS criteria; specificity was 91.3% for both.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Meios de Contraste/farmacologia , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade , Ultrassonografia/métodosRESUMO
BACKGROUND: Renal leiomyoma is a challenging diagnostic and therapeutic condition. Given that 90% of leiomyomas originate from the renal capsule, leiomyoma presenting as a renal parenchymal mass is extraordinarily rare. CASE PRESENTATION: Herein, we report the clinical and imaging features of a patient with renal leiomyoma occurring in the renal parenchyma and mimicking renal cell carcinoma. We also review the clinical, imaging, and histological features of renal leiomyoma. CONCLUSION: An initial partial, simple or radical nephrectomy according to tumor size and patient's underlying condition is suitable for larger, heterogeneous, and non-peripherally located tumors, even if they demonstrate hypointensity on T1- and T2-weighted images, considering the possibility of other diagnoses.
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Carcinoma de Células Renais , Neoplasias Renais , Leiomioma , Humanos , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Leiomioma/diagnóstico por imagem , Leiomioma/patologia , Nefrectomia , Diagnóstico por ImagemRESUMO
Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and lethal lung disease characterized by progressive dyspnea and irreversible loss of lung function. Pirfenidone is a novel anti-fibrotic and anti-inflammatory drug, which reduces deterioration in the lung function and prolongs progression-free survival in patients with IPF. However, it has adverse effects including gastrointestinal symptoms, hepatic dysfunction or skin photosensitivity, and rash. Lichenoid drug eruption (LDE) refers to lichen planus-like drug eruption usually presenting symmetric eczematous plaques with a purple hue. To date, numerous cases of LDE due to various drugs and pirfenidone-associated photosensitivity have been reported. However, a case of pirfenidone-induced LDE has been very rarely reported to our knowledge. Herein, is a case of pirfenidone-induced LDE so that clinicians can be aware of the possibility of LDE when using pirfenidone.
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BACKGROUND. In LI-RADS version 2018, observations showing at least one of five targetoid appearances in different sequences or postcontrast phases are categorized LR-M, indicating likely non-hepatocellular carcinoma (HCC) malignancy. OBJECTIVE. The purpose of this study was to evaluate interobserver agreement for LI-RADS targetoid appearances among a large number of radiologists of varying experience and the diagnostic performance of targetoid appearances for differentiating HCC from non-HCC malignancy. METHODS. This retrospective study included 100 patients (76 men, 24 women; mean age, 58 ± 9 [SD] years) at high risk of HCC who underwent gadoxetic acid-enhanced MRI within 30 days before hepatic tumor resection (25 randomly included patients with non-HCC malignancy [13, intrahepatic cholangiocarcinoma; 12, combined HCC-cholangiocarcinoma]; 75 matched patients with HCC). Eight radiologists (four more experienced [8-15 years]; four less experienced [1-5 years]) from seven institutions independently assessed observations for the five targetoid appearances and LI-RADS categorization. Interobserver agreement and diagnostic performance for non-HCC malignancy were evaluated. RESULTS. Interobserver agreement was poor for peripheral washout (κ = 0.20); moderate for targetoid transitional phase or hepatobiliary phase appearance (κ = 0.33), delayed central enhancement (κ = 0.37), and targetoid restriction (κ = 0.43); and substantial for rim arterial phase hyperenhancement (κ = 0.61). Agreement was fair for at least one targetoid appearance (κ = 0.36) and moderate for at least two, three, or four targetoid appearances (κ = 0.43-0.51). Agreement for individual targetoid appearances was not significantly different between more experienced and less experienced readers other than for targetoid restriction (κ = 0.63 vs 0.43; p = .001). Agreement for at least one targetoid appearance was fair among more experienced (κ = 0.29) and less experienced (κ = 0.37) reviewers. Agreement for at least two, three, or four targetoid appearances was moderate to substantial among more experienced reviewers (κ = 0.45-0.63) and moderate among less experienced reviewers (κ = 0.42-0.56). Existing LR-M criteria of at least one targetoid appearance had median accuracy for non-HCC malignancy of 62%, sensitivity of 84%, and specificity of 54%. For all reviewers, accuracy was highest when at least three (median accuracy, 79%; sensitivity, 68%; specificity, 82%) or four (median accuracy, 80%; sensitivity, 54%; specificity, 88%) targetoid appearances were required. CONCLUSION. Targetoid appearances and LR-M categorization exhibited considerable interobserver variation among both more and less experienced reviewers. CLINICAL IMPACT. Requiring multiple targetoid appearances for LR-M categorization improved interobserver agreement and diagnostic accuracy for non-HCC malignancy.