Simulation of endoscopic third ventriculostomy in fresh cadaveric specimens.

OBJECTIVE: The purpose of this research is to describe and analyze the endoscopic anatomy of cerebral ventricles, especially of the lateral ventricle and third ventricle. METHODS: 47 brains of adult human cadavers were studied at the Death Check Unit (DCU) of São Paulo. Age, sex, day and approximate time of death, day and time of study, cause of death, outcome of puncture and number of attempts were recorded. A rigid neuroendoscope was utilized. The approach to the ventricular system was via the pre-coronal point on the right side. RESULTS: The number of individuals studied was 47, of which 22 (47%) were women and 25 (53%) were men. Age ranged from 20 to 95 years. The minimum time lag between the death and the study was 8 h and the maximum time was 29 h. Of the cadavers studied, three presented alterations in the central nervous system as the cause of death. Successful puncture was obtained in 42 (89%) being 72% in the first attempt. In the analysis performed by Fisher's exact test with a 5% level of significance, an association between the number of attempts (2) and the cause of cerebral death was found (p=0.018). CONCLUSIONS: The visualization of neural structures without bleeding, the possibility of training techniques such as third ventriculostomy, the development of new techniques and to help sctructure new concepts about anatomic landmarks have by far overcome the difficulties.

Easy sellar reconstruction in endoscopic endonasal transsphenoidal surgery with polyester-silicone dural substitute and fibrin glue: technical note.

OBJECTIVE: To describe a simple method of sellar reconstruction after endoscopic endonasal transsphenoidal surgery that will allow rapid watertight closure of the sellar floor. METHODS: A bent sheet of a polyester-silicone dural substitute, fashioned for this purpose with scissors, is introduced into the sella after removal of the lesion. Because of the consistency of the sheet, it opens spontaneously and becomes stuck. Autologous fat tissue or gelatin foam is positioned thereafter, followed by another layer of the dural substitute; a film of fibrin glue completes the sealing. RESULTS: Fifteen patients underwent this method and no postoperative cerebrospinal leak or other complication was experienced. CONCLUSION: This easy method of sellar reconstruction represents an effective and fast possibility to perform the final step of the endoscopic transsphenoidal procedure, which otherwise may cause maneuverability problems in the limited space of one nostril.

Heat transfer to the periodontal ligament during root obturation procedures using an in vitro model.

It appears to be important to avoid thermal injury to the periodontal ligament when using heated guttapercha techniques such as "System B." An in vitro model was developed, consisting of an extracted human tooth rooted in an artificial periodontal ligament (PDL) and alveolar socket, which allowed us to measure the temperature transferred to the root surface. The teeth were instrumented and subsequently embedded in alginate to simulate the PDL. Medium gutta-percha points were fit, sealer was applied, and a fine Buchanan plugger was used for condensation. Temperature measurements were taken simultaneously at the apex and 5 mm from the apex during obturation with two fine gauge thermocouples connected to a digital thermometer. The average temperature increase was approximately 1 degree C at the apex and approximately 2 degrees C at the 5 mm mark. The resulting temperature increases appear to be lower than previously reported by other investigators (Hardie, 1986, 1987; Barkhordar et al., 1990; Weller et al., 1991; Lee et al., 1998), who did not allow for the heat disseminating effect of the PDL.

High-dose cisplatin with dipyridamole in advanced non-small cell lung cancer. A Grupo Oncológico Cooperativo del Sur study.

From March 1991 to October 1992, 41 patients with advanced non-small cell lung cancer (NSCLC) (20 stage IIIB and 21 stage IV) received a regimen consisting of cisplatin (CP) 100 mg/m2 i.v. days 1 and 8, and dipyridamole (DPD) 100 mg p.o. 75 minutes before CP, and then at hours 6, 12, and 18 as first-line chemotherapy. Cycles were repeated every 28 days for a total of 3. Median age was 56 years (range: 40-70). All patients had a performance status 0 to 1 and a weight loss < or = 10%. Squamous-cell carcinoma was diagnosed in 19 patients; adenocarcinoma in 16, and large-cell carcinoma in 6. A total of 37 patients were fully evaluable for response, whereas 39 were assessable for toxicity. No complete responses were observed: 5 patients (14%) achieved partial response; 23 patients (62%) showed no change, and progressive disease was observed in 9 (24%). The median time to treatment failure was 4 months, whereas median survival was 8 months. The average dose intensity received at the end of the third course of therapy was 46 mg/m2/week. There were no drug-related deaths. Toxicity was mild to moderate, with a high incidence of ototoxicity (54%) and emesis (67%). In conclusion, these results failed to demonstrate any significant advantage from a high-dose CP regimen modulated by DPD in patients with advanced NSCLC.