Sterilization with methyl cyanoacrylate-induced fallopian tube occlusion from a nonsurgical transvaginal approach in rabbits.

PURPOSE: To evaluate a nonsurgical, nonhormonal sterilization procedure performed with use of transvaginal microcatheterization techniques and methyl cyanoacrylate (MCA) as a sclerosing agent MATERIALS AND METHODS: Seventeen adult virgin female rabbits underwent bilateral fallopian tube cannulation through a nonsurgical transvaginal approach with use of a coaxial catheter system with fluoroscopic guidance. Fourteen of the rabbits underwent bilateral fallopian tube occlusion with direct MCA injection; the remaining three rabbits were separated as controls. Three of the rabbits with occlusions were killed as temporal histologic controls. The remaining 11 rabbits with occlusions and the initial three controls underwent 6 months of mating trials. All 17 rabbits were killed. Gross inspection was performed and histologic specimens of their fallopian tubes were obtained. RESULTS: None of the 11 rabbits with occlusions that underwent mating became pregnant. All three control rabbits became pregnant. Histologic examination of the occluded fallopian tubes demonstrated long-segment tubal wall fibrosis with varying degrees of occlusion. No peritoneal abnormalities were identified. Histologic findings for the three control animals were normal. CONCLUSION: With use of a nonsurgical transcervical coaxial catheter system, MCA can be placed directly into fallopian tubes without difficulty. MCA administration leads to fallopian tube fibrosis and occlusion. A 100% nonpregnancy rate was demonstrated. Further investigation may lead to a safer, more convenient, and less expensive form of permanent sterilization.

Intramedullary lesions of the pediatric spinal cord: correlation of findings from MR imaging, intraoperative sonography, surgery, and histologic study.

Findings of preoperative magnetic resonance (MR) imaging and radiologist-directed intraoperative sonography (IOS) were correlated with surgical and pathologic findings in 11 pediatric patients with intramedullary spinal cord lesions. There were seven gliomas and one each of primitive neuroectodermal tumor, venous vascular malformation, neuroenteric cyst, and active schistosomiasis. MR imaging provided discrete preoperative anatomic localization and excluded multicentric lesions but did not reliably distinguish between solid and cystic lesions. IOS helped (a) define the limits of intramedullary mass before the dura mater was opened and (b) differentiate cystic from solid components. The internal architecture of intramedullary lesions, as shown with MR imaging and sonography, was strikingly similar, allowing discrete correlative localization for biopsy or tissue resection. Gadolinium-enhanced MR imaging and IOS are complementary imaging techniques that should be used in concert for the evaluation and management of intramedullary lesions of the pediatric spinal cord. Both techniques display regions of cord abnormality, but neither definitively characterizes underlying tissue histology.