Os nossos objetivos foram estabelecer a eficácia da tomografia computadorizada sem contraste em diagnosticar a ureterolitíase, calcular a freqüência dos principais sinais tomográficos e medir a concordância interobservador, comparando-a com os resultados obtidos na urografia excretora, realizando estudo prospectivo duplo-cego em 25 pacientes com cólica nefrética. Em ambos os procedimentos avaliamos a existência de aumento renal, hidronefrose e cálculo ureteral. Deste último, descrevemos a sua localização e dimensão. Nos exames de tomografia computadorizada sem contraste procuramos também por estrias perirrenais, edema periureteral e o sinal do halo. Em 23 dos 25 exames de tomografia computadorizada sem contraste (92%) e em 17 das 25 urografias excretoras (68%) houve concordância dos resultados entre os dois observadores. Em 21 dos 25 pacientes os resultados dos dois métodos foram concordantes. Concluímos que a tomografia computadorizada sem contraste apresenta eficácia superponível à urografia excretora na avaliação de pacientes com cólica nefrética, sendo um método reprodutível e sem promover o desconforto do uso do contraste endovenoso.

Our purpose was to evaluate the accuracy of unenhanced helical computed tomography in the diagnosis of ureteral lithiasis, to establish the frequency of the main computed tomography findings, and to assess and compare the interobserver agreement with the results of conventional intravenous urography. A prospective double-blind study was carried out in 25 patients referred for unenhanced helical computed tomography and conventional intravenous urography due to nephretic colic. Both methods were employed to evaluate the size of the kidneys, hydronephrosis and the size and location of ureteral stones. Perirenal hyperdensities, periureteral edema and the halo sign were also assessed by unenhanced helical computed tomography. In 23 of the 25 unenhanced helical computed tomography examinations (92%) and in 17 of the 25 conventional intravenous urography examinations (68%) there was agreement on the results of the two observers. In 21 of the 25 patients, there was agreement between the results of both methods. We concluded that unenhanced helical computed tomography is as efficient as conventional intravenous urography in the evaluation of patients with nephretic colic, is a reproducible method, and avoids the discomfort of the use of intravenous contrast.