Safer video-assisted thoracoscopic thymectomy after location of thymic veins with multidetector computed tomography.

BACKGROUND: Video-assisted thoracoscopic (VATS) thymectomy has been applied as a surgical option for autoimmune myasthenia gravis. Prior identification and fine division of the thymic veins are critical to the prevention of unexpected severe bleeding that may require conversion to open surgery. Until recently, such bleeding could be avoided only by meticulous dissection of thymic fat tissue away from the left brachiocephalic vein (LBV). With recent advances in computed tomography (CT), multidetector-row computed tomography (MDCT) can readily be obtained and provides three-dimensional (3D) images. This study explored its value for preoperative identification of the thymic veins draining into the LBV, and thus for prevention of injury to these veins during endoscopic thymectomy. METHODS: Five patients with myasthenia gravis, thymoma, or both underwent enhanced MDCT preoperatively. The thymic veins draining into the LBV were visualized using both horizontal and sagittal/coronal CT images. Then 3D images were reconstructed to enable operators to simulate endoscopic views. During each VATS extended thymectomy, the numbers and branching patterns of the thymic veins were compared with the preoperative MDCT images. RESULTS: The thymic veins draining into the LBV were clearly identified with MDCT in all five patients examined. Reconstructed 3D images clearly located their courses in the thymic/fat tissue and their entry routes into the LBV, thus simulating the actual intraoperative endoscopic views. All tributaries divided during surgery were identified preoperatively with MDCT. CONCLUSIONS: Location of thymic veins with MDCT can provide precise preoperative information about thymic venous anatomy. This easy and less invasive examination has the potential to make VATS thymectomy easier and safer.

Nonfunctioning islet cell carcinoma of the pancreas associated with massive intra-abdominal hemorrhage.

Pancreatic islet cell tumors are rarely associated with intra-abdominal hemorrhage. We report herein a rare case of nonfunctioning islet cell carcinoma associated with massive hemorrhage into the abdominal cavity caused by spontaneous rupture of the tumor. A 44-year-old man presenting with sudden upper abdominal pain was admitted to his local hospital on April 18, 1994. On April 19, a laparotomy was performed with the diagnosis of peritonitis. Massive hemorrhage of unknown origin occurred, and he was transferred to our hospital in a state of hypovolemic shock. Imaging findings revealed massive hematoma in the abdominal cavity and a hypervascular tumor arising from the body of the pancreas. Because the hemorrhage was life-threatening, an emergent re-laparotomy was performed on April 20. Apart from the massive hemorrhage, a pancreatic tumor (60 x 35 x 30 mm in size) with spontaneous rupture was noted. Distal pancreatectomy, combined with splenectomy and removal of the hematoma, was performed. Histological findings revealed an islet cell carcinoma of the pancreas with venous invasion. Peritoneal dissemination, liver metastasis, and lymph node metastasis were not observed. The patient is alive without recurrence 6 years and 5 months after the operation.

Adrenergic regulation of prostaglandin biosynthesis in cultured rabbit gastric epithelial cells.

Adrenergic regulation of prostaglandin (PG) biosynthesis was investigated in 1-14C-arachidonic acid-prelabeled cultured rabbit gastric epithelial cells (RGECs). RGECs expressed adrenergic alpha 1- and beta-receptors and muscarinic receptors. Norepinephrine facilitated the synthesis of PGs I2 (determined as the stable metabolite 6-keto PGF1 alpha) and E2 and hydroxyfatty acids, while epinephrine facilitated the synthesis of PGI2 and hydroxyfatty acids, but not PGE2. However, isoproterenol did not affect PG biosynthesis. The effects of norepinephrine and epinephrine on PG biosynthesis were markedly suppressed by the non-selective alpha-blocker phentolamine and/or the selective alpha 1-blocker prazosin. In combination with epinephrine, the selective alpha 2-blocker yohimbine or the beta-blocker propranolol facilitated PGE2 synthesis. Acetylcholine did not affect PG biosynthesis. These results indicate that norepinephrine and epinephrine act on PG biosynthesis as adrenergic agonists in these cultured RGECs and that an alpha 1-receptor couples PGI2 and PGE2 synthesis.