Papel da ranitidina como meio de aprimorar a qualidade do exame de colangiopancreatografia por ressonância magnética / The role of ranitidine in the enhancement of imaging quality in magnetic resonance cholangiopancreatography

OBJETIVO: Avaliar o impacto da ranitidina por via oral na qualidade do exame de colangiopancreatografia por ressonância magnética (CPRM).MATERIAIS E MÉTODOS: Trinta e dois pacientes realizaram CPRM com aquisições 3D e 2D, com três estratégias de supressão do sinal líquido gastrintestinal: a) apenas em jejum; b) 12 horas após ingerir 300 mg de ranitidina; c) após a ingestão de solução de gadolínio. Três observadores avaliaram os estudos, atentos para o grau de visualização da árvore biliopancreática. Foi medida a concordância interobservador com o teste kappa. A diferença entre técnicas e formas de aquisição foi avaliada pela média da soma dos escores de graduação.RESULTADOS: As três estratégias de supressão do sinal líquido gastrintestinal apresentaram elevada reprodutibilidade. A supressão do sinal líquido gastrintestinal com a ranitidina foi semelhante ao jejum e ambas foram piores do que a solução de gadolínio. As aquisições 3D superaram a 2D apenas na visualização do ducto cístico e da vesícula biliar, sendo inferior ou equivalente nos demais segmentos ductais biliopancreáticos.CONCLUSÃO: O uso da ranitidina não parece justificado para aprimorar a avaliação da árvore biliopancreática em exames de CPRM. A CPRM 2D apenas em jejum permite a visualização ductal com elevada qualidade e reprodutibilidade na maioria dos casos.

OBJECTIVE: To assess the impact of oral ranitidine on the imaging quality in magnetic resonance cholangiopancreatography (MRCP).MATERIALS AND METHODS: Thirty-two patients underwent MRCP with 3D and 2D acquisitions, and three strategies for suppression of the gastrointestinal fluid signal: a) only at fasting; b) 12 hours after ingestion of 300 mg ranitidine; c) after oral administration of gadolinium solution. Three observers reviewed the images with a focus on the degree of visualization of the biliopancreatic tree. The interobserver agreement was evaluated with the kappa test. The difference between techniques and acquisition modalities were evaluated by means of average grading scores.RESULTS: The three strategies for suppression of the gastrointestinal fluid signal presented high reproducibility. The results with suppression of the gastrointestinal fluid signal with ranitidine where similar to those obtained with fasting, and both were worse than those obtained with gadolinium solution. The 3D acquisitions surpassed 2D only in terms of visibility of the cystic duct and gallbladder, and were inferior or equivalent in the other biliopancreatic ductal segments.CONCLUSION: The use of ranitidine does not seem justified in the evaluation of the biliopancreatic tree at MRCP, since 2D MRCP with fasting allows the visualization of ductal structures with high quality and reproducibility in the majority of cases.

Rendimiento de la colangiografía por resonancia magnética en el diagnóstico de coledocolitiasis / Accuracy of magnetic resonance cholangiopancreatography for the diagnosis of common bile duct stones

Magnetic resonance cholangiopancreatography MRCP) is a non-invasive diagnostic method for choledocholithiasis. Aim: To evaluate the results of MRCP in the diagnosis of choledocholithiasis. Patients and methods: Retrospective review of MRCP reports performed between October 2001 and December 2004. We included patients with suspected choledocholithiasis who were studied with MRCP and some other confirmatory test such as endoscopic retrograde cholangiopancreatography ERCP), surgical common bile duct exploration or transcystic colangiography TC). Results: One hundred and twenty five patients aged 58±20 years 70 females) were included. In 54 patients 43 percent) we compared the results of MRCP with the findings of surgical common bile duct exploration or TC and in 71 57 percent) we did so with ERCP. MRCP suggested choledocholithiasis in 93 patients and in 32 it was negative. Eighty six 67 percent) patients had choledocholithiasis according to TC or ERCP, including 3 patients who had a negative MRCP. Therefore the sensibility was 97 percent, specificity 74 percent positive predictive value 89 percent, negative predictive value 90 percent and accuracy of MRCP was 90 percent for the diagnosis of choledocholithiasis. Conclusions: MRCP has a high accuracy for the diagnosis of choledocholithiasis.