Intrapulmonary lymph nodes: thin-section CT findings, pathological findings, and CT differential diagnosis from pulmonary metastatic nodules.

We compared the thin-section CT findings of 11 intrapulmonary lymph nodes with pathological findings and evaluated the possibility of CT scan differential diagnosis from pulmonary metastatic nodules. First, we retrospectively reviewed CT scan and pathological findings of intrapulmonary lymph nodes. The median size of these nodules was 6.2 mm. The nodules appeared round (n=3) or angular (n=8) in shape with a sharp border, and they were found below the level of the carina. The median distance from the nearest pleural surface was 4.6 mm, and 3 of the 11 nodules were attached to the pleura. On thin-section CT scan, linear densities extending from the intrapulmonary lymph nodes were frequently visualized, and were pathologically proven to be ectatic lymphoid channels. We then compared the thin-section CT findings of 8 metastatic nodules less than 1 cm in diameter with those of the 11 intrapulmonary lymph nodes. The median size of these nodules was 6.8 mm, and the median distance from the nearest pleural surface was 16 mm. All nodules appeared round in shape. None of the nodules had linear densities extending from the nodules. The linear densities on thin-section CT scan may be the most useful characteristic of intrapulmonary lymph nodes, when differential diagnosis from metastatic nodules is necessary.

Comparison of Tc-99m-GSA scintigraphy with hepatic fibrosis and regeneration in patients with hepatectomy.

OBJECTIVE: Liver regeneration after hepatectomy is correlated with liver fibrosis. Retrospectively, we compared three quantitative indices (HH15, LHL15 and LU15) of Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (Tc-99m-GSA) liver scintigraphy with liver fibrosis; in particular, we compared the HH15 index and the rate of remnant liver regeneration. METHODS: Fifty-three patients who had undergone hepatectomy were enrolled in this study. The non-neoplastic parts of their resected specimens were divided into 5 groups (F0-F4) according to the degree of liver fibrosis, as determined using the New Inuyama classification system: F0, no fibrosis (n = 12); F1, portal fibrosis widening (n = 12); F2, portal fibrosis widening with bridging fibrosis (n = 14); F3, bridging fibrosis plus lobular distortion (n = 7); F4, liver cirrhosis (n = 8). RESULTS: When the cases were divided into a no or mild fibrosis group (F0 and F1) and a moderate or severe fibrosis or cirrhosis group (F2, F3 and F4), all of the indices were significantly different between the two groups. In this analysis, the areas (Az) under the receiver operating characteristic (ROC) curves for the HH15 and LHL15 indices were very similar, while the Az for the LU15 index was smaller. An HH15 index equal to 0.52 was the most accurate, producing a 79.3% sensitivity and a 75.0% specificity rating. When 18 patients that had received a CT scan one month after hepatectomy were divided into 2 groups according to their HH15 value (group A, HH15 < or = 0.52; group B, HH15 > 0.52), group A exhibited a better regeneration rate. CONCLUSION: Tc-99m-GSA scintigraphy is well correlated with liver fibrosis and may be useful for non-invasive, preoperative evaluations of liver fibrosis. The HH15 index, in particular, may be useful for predicting the rate of liver regeneration after hepatectomy.

Preoperative localization of small pulmonary lesions with a short hook wire and suture system: experience with 168 procedures.

PURPOSE: To evaluate use of a short hook wire and suture system for preoperative localization of pulmonary nodular lesions. MATERIALS AND METHODS: Percutaneous localization of 168 lesions was performed with computed tomographic (CT) guidance in 150 patients. Patients were classified into three groups: a 3-year early-learning experience of treatment of 40 lesions mainly in one institution (group A1), a more recent 4-year experience of treatment of 88 lesions in the same institution (group A2), and the roughly synchronous recent 3-year experience of treatment of 40 lesions in a different hospital (group B). RESULTS: The hook wire was successfully placed without dislodgment in 146 patients, accounting for 164 (97.6%) of 168 lesions. Group A2 showed a success rate of 100%. There was no difference in patients among the three groups in regard to size of lesions or their distance from the pleural surface. In patients in groups A2 and B, the proportion of nodules with ground-glass opacity and primary lung carcinoma at CT was significantly greater than that in patients in group A1. In 168 placements, nonsymptomatic pneumothorax cases were observed in 54 (32.1%), hemorrhages into the lung were observed in 25 (14.9%), and hemorrhage into the pleural space was observed in one (0.6%). No patient complained of notable pain during or after the procedure, and no serious complication was experienced. Unsuccessful placement was caused by too shallow a puncture with the introducer needle. CONCLUSION: This system with a flexible suture for preoperative localization has a high success rate.