Unilateral and Bilateral Lumbosacral Transitional Vertebrae: Comparison of the Incidence of Combined Diseases

PURPOSE: The purpose of this study was to evaluate the radiologic findings of lumbosacral transitional verte-brae (LSTV), as seen on plain radiographs and MRI, and to compare the incidence of combined diseases be-tween unilateral and bilateral groups. MATERIALS AND METHODS:We retrospectively evaluated the plain radiographs and MR images of 63 patients with LSTV, classifying its type according to Castellvi 's criteria, and evaluated disc herniations, facet joint os-teoarthritic change, scoliosis, and spondylolisthesis. We then compared the incidence of each combined diseases between unilateral and bilateral groups, and as a control group, 63 patients without LSTV were also eval-uated. RESULTS: Forty of 63 cases of LSTV (63.5%) were bilateral, and 23 (36.5%) unilateral. According to Castellvi 's criteria, the incidence of type I was 41.3% (unilateral 7 cases, bilateral 19), type III30.2% (unilateral 8 cases, bilateral 11), type II23.8% (unilateral 8 cases, bilateral 7), and type IV 4.8% (unilateral 0 cases, bilateral 3).With combined diseases, the incidence of disc herniation was 66.7% (unilateral 15 cases, bilateral 27), moderate to severe facet joint osteoarthritic change 28.6% (unilateral 11 cases, bilateral 7), scoliosis 27.0% (unilateral 9 cases, bilateral 8), and spondylolisthesis 9.5% (unilateral 2 cases, bilateral 4). The incidence of facet joint os-teoarthritic change was significantly higher in the unilateral group (47.8%) than in the bilateral group (17.5%) (p=0.02), and scoliosis occurred at a higher rate in the unilateral group (39.1%) than in the bilateral group (20.0%) (p=0.18). There was, however, no significant difference in the incidence of disc herniation and spondylolisthesis between the two groups (unilateral group: 65.2% and 8.7%; bilateral group: 67.5% and 10.0%, respectively). CONCLUSION: With LSTV, the incidence of facet joint osteoarthritic change was significantly higher in the unilat-eral group than in the bilateral group, and scoliosis also showed a higher rate of occurrence in the unilateral group.

Recurrent Pyogenic Cholangitis: Efficacy of Two-Phase Helical CT

PURPOSE: To evaluate the usefulness of two-phase helical CT in patients with recurrent pyogenic cholangitis (RPC) for the detection of acute inflammation and assessment of the degree of portal vein (PV) stenosis as a cause of hepatic parenchymal atrophy. MATERIALS AND METHODS: We retrospectively reviewed two-phase CT findings in 30 patients with RPC diagnosed by CT, ERCP (endoscopic retrograde cholangiopancreatography), and surgery. Two-phase helical CT scans were obtained 30 sec (arterial phase, AP) and 70 sec (portal phase, PP) after the start of IV administration of contrast material. Without prior information, we analyzed periductal parenchymal and ductal wall enhancement during the AP and PP, and the degree of PV stenosis during the PP. Acute inflammation was diagnosed on the basis of symptoms and laboratory findings. To evaluate the relationship between parenchymal atrophy and PV stenosis, the degree of PV stenosis in affected parenchyma was classified as one of three types (mild,75%), as compared with the diameter of normal PV in unaffected parenchyma. RESULTS: Ten of the 30 patients underwent CT during the acute inflammatory stage and 20 during the remission stage. Of the ten patients with acute inflammation, eight (80%) showed transient periductal parenchymal enhancement during the AP (p0.05). There was no significant difference in parenchymal and ductal wall enhancement during the PP between patients with acute inflammation and those who showed remission (p>0.05). Hepatic parenchymal atrophy of the lesion was seen in 24 patients. Among these, PV stenosis was mild in five (21%), moderate in 14 (58%), and severe in five (21%). Degree of PV stenosis correlated closely with severity of parenchymal atrophy during the PP. In six patients without parenchymal atrophy, PV caliber was normal. CONCLUSION: Our results suggest that in patients with RPC, two-phase helical CT is useful for the detection of transient periductal parenchymal enhancement accompanying acute inflammation during the AP, and for assessment of the degree of PV stenosis as a cause of hepatic parenchymal atrophy during the PP.

Gastric Stromal Tumor: Two-Phase Dynamic CT Findings with Water as Oral Contrast Agents

PURPOSE: To evaluate two-phase dynamic CT with water as oral contrast agents in the CT diagnosis of gastric stromal tumors. MATERIALS AND METHODS: We retrospectively reviewed the CT findings in 21 patients with pathologically proven gastric stromal tumors. Six were found to be benign, twelve were malignant, and there were three cases of STUMP (stromal tumor uncertain malignant potential). Two-phase dynamic CT scans with water as oral contrast agents were obtained 60-70secs (portal phase) and 3 mins (equilibrium phase) after the start of IV contrast administration. We determined the size, growth pattern, and enhancement pattern of the tumors and overlying mucosa, the presence or absence of ulceration and necrosis, tumor extent, and lymph node and distant metastasis. The CT and pathologic findings were correlated. RESULTS: All six benign tumors and three STUMP were less than 5.5 cm in size, and during the portal phase showed round endogastric masses with highly enhanced, intact overlying mucosa. Twelve malignant tumors were 4.5-15.5 cm in size (mean, 11.5cm); an endogastric mass was seen in three cases, an exogastric mass in one, and a mixed pattern in eight. On portal phase images the tumors were not significantly enhanced, but highly enhanced feeding vessels were noted in five larger tumors (> 10 cm). All 12 malignant tumors showed ulceration and necrosis, and interruption of overlying mucosa was clearly seen during the portal phase. We were readily able to evaluate tumor extent during this phase, and in ten malignant tumors there was no invasion of adjacent organs. Seven malignant tumors showed air density within their necrotic portion (p<0.05). On equilibrium phase images, all malignant tumors showed heterogeneous enhancement due to necrosis, and poorly enhanced overlying mucosa. CONCLUSION: Dynamic CT during the portal phase with water as oral contrast agents was useful for depicting the submucosal origin of gastric stromal tumors and for evaluating the extent of malignant stromal tumors. Our results suggest that these CT findings may be helpful for differentiating between benign and malignant stromal tumors, and in distinguishing them from other gastric tumors.