Objective To explore the therapeutic efficacy of a new type sapphire contact laser using wavelength-shifting technique on microsurgery of brain stem tumors.Methods The clinical data were retrospectively analyzed of 23 patients(13 males and 10 females,aged 6 to 69 years with an average of 38 years,and the duration of disease was 14 to 36 months with average of 22 months) with brain stem tumor admitted from Mar.2006 to May 2010.The major symptoms of the patients were cranial nerve impairment,cerebellum function impairment or paralysis.All patients received microsurgical resection of brain stem tumor using sapphire contact laser through median suboccipital incision and posterior brain stem approach,and the tumors were resected with precision operation and vaporization and ablation.Results Of the 23 patients,4 were with glioma,15 with cavernous angioma,2 with angioreticuloma and 2 with metastatic tumor.Total resection was achieved in 15 cases,while subtotal resection(more than 80%) in 6 cases.Intraoperative hemorrhage was less and no intraoperative blood transfusion was required.A 6-months follow-up showed symptoms recovered in 15 patients,improved in 4,unchanged in 2,and worsen in 1.One patient died of recurrence of tumor.No postoperative intracranial infection was occurred,and 2 patients were undergone tracheotomy after operation.The average hospital stay was 15d.Conclusion The contact laser can precisely dissect and vaporize the tumors,increase the resection rate,reduce intraoperative hemorrhage and accessory injuries,and has a clear and definite effect.