LI-RADS 4 or 5 categorization may not be clinically relevant for decision-making processes: A prospective cohort study.

INTRODUCTION AND OBJECTIVES: The liver imaging reporting data system (LI-RADS) for hepatocellular carcinoma (HCC) was proposed to standardize and enhance consensus of reporting. However, clinical utility of LI-RADS has not been evaluated in Latin America. We therefore sought to compare LI-RADS categories with histopathology findings in liver transplant (LT) explants in a regional center. MATERIALS AND METHODS: Prospective cohort study conducted between 2012 and 2018 in a single center from Argentina including patients with HCC listed for LT. LI-RADS definitions were applied to magnetic resonance images (MRI) or computed tomography (CT) abdominal scans at time of listing and at final pre-LT reassessment and compared to explant pathology findings; specifically, major nodule (NOD1). RESULTS: Of 130 patients with HCC listed for LT (96.1% with cirrhosis and 35.6% with hepatitis C virus infection), 72 underwent LT. Overall, 65% had imaging HCC diagnosis based on MRI (n = 84), 26% with CT (n = 34) and 9% (n = 12) with both methods. Among LT patients with pre-transplant imaging at our institution (n = 42/72), 69% of the NOD1 were LR-5, 21% LR-4 and 10% LR-3. Definite HCC diagnosis was 50% in LR-3 NOD1 (CI 18-90); none presented microvascular invasion. In LR-4 NOD1, HCC was confirmed in 89% (CI 59-98), of which 11% showed microvascular invasion; whereas in LR-5 NOD1 77% (CI 64-87) had confirmed HCC, 17% with microvascular invasion. CONCLUSIONS: LI-RADS was useful to standardize reports; however, no significant differences were observed between LR-4 and LR-5 HCC probability when compared to explant pathology.

Empiema del Muñón Ureteral: Secretos Para un Buen Diagnóstico / Empyema of the Ureteral Stump: Secrets for a Correct Diagnosis

El muñón ureteral es el segmento de uréter remanente posterior a una nefrectomía, que puede, ocasionalmente, dar origen a un cuadro sintomático infeccioso poco frecuente, conocido como empiema del muñón ureteral (EMU). El mismo suele atribuirse a otra patología por desconocimiento médico y no es reconocido hasta que el cuadro clínico avanza significativamente o se realiza la exploración quirúrgica. Los muñones ureterales que se encontraban sanos en la cirugía inicial no suelen desarrollar patología. Por el contrario, los uréteres obstruidos, crónicamente infectados o asociados a litiasis o reflujo distal, son los que se encuentran en riesgo de desarrollar complicaciones futuras. En esta revisión, se repasa la literatura y se presentan casos de pacientes con antecedentes de nefrectomía que por diferentes causas transcurrieron con empiema en el muñón ureteral, con el fin de analizar las posibles causas y factores predisponentes de la patología, describir los hallazgos radiológicos en los diferentes métodos diagnósticos y poder reconocer las posibles complicaciones para su correcto manejo terapéutico. Las infecciones urinarias a repetición son útiles para sospechar la presencia de EMU. Ellas se deben al reflujo urinario o disfunción en el vaciamiento del uréter remanente, con estasis e infección del mismo. Por lo tanto, en pacientes con antecedentes de nefrectomía que presentan dolor abdominal difuso, fiebre y antecedentes de infecciones urinarias a repetición, es necesario sospechar empiema del muñón ureteral para poder realizar un correcto análisis imagenológico y posterior tratamiento.

The ureteral stump is the segment of the ureter that remains after a nephrectomy, and it can occasionally give rise to a rare symptomatic infectious disorder known as an empyema of the ureteral stump. The syndrome is usually attributed to another disease due to the radiologist's or ED physician's unawareness, and diagnosis is delayed until there is significant clinical progression, complimentary images or exploratory surgery is performed. Ureteral stumps that were healthy at the initial surgery, usually do not pose further problems. On the other hand, ureters that are obstructed, chronically infected or associated with nephrolithiasis or distal reflux, are at risk for developing future complications. This review goes over the available literature on the subject and presents cases of patients who underwent a nephrectomy and, for different reasons, developed an empyema of the ureteral stump in order analyze the possible causes and predisposing factors, describing the main radiologic findings in each of the different imaging modalities, and recognize the possible complications and their according therapeutic management. Repeated urinary tract infections are useful for suspecting the presence of an empyema, and are due to vesicoureteral reflux or ureteral dysfunction, with consequent urinary stasis and infection. Thus, patients with a history of nephrectomy presenting with diffuse abdominal pain, fever and repeat urinary infections, should raise the suspicion of empyema of the ureteral stump, leading to a correct imaging analysis and posterior treatment.

Approach to Pulmonary Hypertension: From CT to Clinical Diagnosis.

Pulmonary hypertension (PH) is a condition characterized by increased pressure in the pulmonary circulation. It may be idiopathic or arise in the setting of other clinical conditions. Patients with PH tend to present with nonspecific cardiovascular or respiratory symptoms. The clinical classification of PH was recently revised at the World Health Organization symposium in Nice, France, in 2013. That consensus statement provided an updated classification based on the shared hemodynamic characteristics and management of the different categories of PH. Some features seen at computed tomography (CT) can suggest a subtype or probable cause of PH that may facilitate placing the patient in the correct category. These features include findings in the pulmonary arteries (peripheral calcification, peripheral dilatation, eccentric filling defects, intra-arterial soft tissue), lung parenchyma (centrilobular nodules, mosaic attenuation, interlobular septal thickening, bronchiectasis, subpleural peripheral opacities, ground-glass opacities, diffuse nodules), heart (congenital lesions, left heart disease, valvular disease), and mediastinum (hypertrophied bronchial arteries). An approach based on identification of these CT features in patients with PH will allow the radiologist to play an important role in diagnosis and help guide the clinician in management of PH. ©RSNA, 2018.