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Background

Data regarding the safety of endoscopic skull base exploration are very scarce. With this method, fragile vital structures (cranial nerves, the optic complex, brainstem, hypothalamus or cerebral ventricles) are exposed to direct illumination within a closed space. Also, high-speed drills, cauterization and ultrasonic aspiration deliver a significant load of thermal energy. The aim of this study was to record the temperature close to the structures of the skull base and in the intradural space during the procedures performed using extended endoscopic transnasal approaches.

Methods

The temperature of the skull base was continuously recorded during six transnasal endoscopic procedures. Implantable copper-constantan thermocouples were inserted: one into the esophagus and another through the nostril to reach the operative field at the skull base.

Results

At the beginning of the procedure, the temperature of the operative field was on average 36.8 °C?±?0.80 °C, i.e. only 1 °C higher than the esophageal temperature. Then it grew continuously during the whole procedure, to eventually reach a level of 42–43 °C at the final stage, whereas the esophageal temperature remained stable. Occasionally, the temperature increased up to 45 °C during cauterization and ultrasonic aspiration, and even up to 62 °C during high-speed drilling.

Conclusion

Endoscopic skull base surgery is associated with an incessant increase of the temperature of the intraoperative field. The temperature can peak suddenly to levels which can potentially harm neural structures and influence the rate of postoperative complications.  相似文献   
994.

Background

There is no consensus about the usefulness of postoperative intact parathyroid hormone (iPTH) determination to predict permanent hypoparathyroidism (pHPP). We evaluated the value of calcium (Ca2+) and iPTH concentration at 24 hours after total thyroidectomy (TT) for predicting pHPP.

Methods

Ca2+ and iPTH levels from 70 consecutive patients who underwent TT were measured at 24 hours and 6 months after TT.

Results

Five patients (7.1%) developed pHPP. An iPTH concentration ≤5.8 pg/mL at 24 hours after TT identified patients at risk for pHPP (sensitivity, 100%; specificity, 81.5%), but it was not accurate enough to predict its development (positive predictive value, 30%). Conversely, an iPTH level >5.8 pg/mL predicted normal parathyroid function at 6 months (negative predictive value, 100%). Compared with iPTH, a postoperative Ca2+ level ≤1.95 mmol/L was 60% sensitive and 78.5% specific to predict pHPP.

Conclusions

An iPTH concentration >5.8 pg/mL on the first postoperative day rules out pHPP with much better diagnostic accuracy than Ca2+. Postoperative iPTH could be helpful in identifying patients at risk for developing pHPP.  相似文献   
995.

Aim of the study

To evaluate the functional outcome of laparoscopic-assisted endorectal pull-through (LAP) for Hirschsprung's disease (HSCR) over time.

Methods

Thirty-five children with HSCR underwent laparoscopic-assisted pull-through at our institution between 1998 and 2009. The diagnosis was histologically confirmed in all cases. Clinical data was extracted from the case records. A prospective assessment of the functional outcome was performed in 2009 and 2012. Exclusion criteria were a follow-up of less than 6 months after treatment (1 case) and total colonic aganglionosis (1 case). An independent examiner, not involved in the clinical care of the patients, performed interviews using a semi-structured questionnaire. Four patients could not be traced for the first interview. Two cases were lost for the second interview. Altogether twenty-seven patients completed the study. Data from the two interviews were compared. The regional ethical review board approved the study.

Main Results

The median patient age was 4 years old (range 2–16) at the time of the first interview and 7 years old (range 5–19) at the time of the second interview . There were 23 males and 4 females in the study group. The median age at laparoscopic-assisted pull-through was 104 days old (range 29 days–8 years). In the first interview 11 patients reported constipation, 18 patients reported soiling more frequently than once per week when they had loose stools and 16 patients when they had solid stools. Laxatives or irrigations were used by 13 of the patients. In the second interview 4 patients reported constipation, 16 patients reported soiling when they had loose stools and 15 patients reported soiling when they had solid stools. Eight patients used laxatives or irrigations. The decrease in constipation was statistically significant (p = 0,023).

Conclusions

Our study shows a statistically significant reduction of constipation over time. There is a high risk of incontinence after laparoscopic-assisted pull-through, with few signs of short-term improvement.  相似文献   
996.

Background

Sublobar resection for non–small cell lung cancer (NSCLC) remains controversial owing to concern about local recurrence and long-term survival outcomes. We sought to determine the efficacy of wedge resection as an oncological procedure.

Methods

We analyzed the outcomes of all patients with NSCLC undergoing surgical resection at the Cancer Centre of Southeastern Ontario between 1998 and 2009. The standard of care for patients with adequate cardiopulmonary reserve was lobectomy. Wedge resection was performed for patients with inadequate reserve to tolerate lobectomy. Predictors of recurrence and survival were assessed. Appropriate statistical analyses involved the χ2 test, an independent samples t test and Kaplan–Meier estimates of survival. Outcomes were stratified for tumour size and American Joint Committee on Cancer seventh edition TNM stage for non–small cell lung cancer.

Results

A total of 423 patients underwent surgical resection during our study period: wedge resection in 71 patients and lobectomy in 352. The mean age of patients was 64 years. Mean follow-up for cancer survivors was 39 months. There was no significant difference between wedge resection and lobectomy for rate of tumour recurrence, mortality or disease-free survival in patients with stage IA tumours less than 2 cm in diameter.

Conclusion

Wedge resection with lymph node sampling is an adequate oncological procedure for non–small cell lung cancer in properly selected patients, specifically, those with stage IA tumours less than 2 cm in diameter.  相似文献   
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