Magnetic resonance cholangiography using half-Fourier acquisition for diagnosing choledocholithiasis.

Abstract

Magnetic resonance cholangiography (MRC), using a half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence, noninvasively provides very rapid (1-2 s) and high-quality images of the biliary tract. We assessed the diagnostic usefulness of HASTE-MRC for choledocholithiasis. A total of 101 patients with suspected choledocholithiasis underwent MRC, ultrasonography, and endoscopic retrograde cholangiopancreatography (ERCP). In 97 patients in whom ERCP fully depicted the common bile duct, we retrospectively analyzed the capability of MRC to image the common bile duct and to diagnose choledocholithiasis, in comparison with that of ultrasonography. In 34 patients, ERCP demonstrated bile duct stones, which were confirmed at endoscopic or surgical treatment. The common bile duct was fully delineated in 98% by MRC and in 70% by ultrasonography. MRC (91%) was more sensitive than ultrasonography (71%) for detecting choledocholithiasis (p < 0.05). MRC demonstrated bile duct stones in all patients with stones > or =11 mm but missed calculi in the 29% of patients with small (3-5 mm) stones. MRC was capable of detecting choledocholithiasis regardless of bile duct caliber. The specificity of MRC (100%) was higher than that of ultrasonography (95%). HASTE-MRC, a fast and noninvasive procedure, can accurately diagnose choledocholithiasis although the detectability for small stones is limited.