[Comparative analysis of neuroendoscope-assisted microsurgery and microscope treatment for small acoustic neuroma]

To explore the outcomes of surgery for the treatment of small acoustic neuroma by the neuroendoscope-assisted microsurgery and microscope.

From 2008 to 2013, 42 patients with small acoustic neuroma underwent neuroendoscope-assisted microsurgery (n = 20) and microscopic tumoural resection (n = 22). Neurophysiological monitoring, 30-degree rigid neuroendoscope and microscope were employed intra-operatively. For the endoscope group, facial nerve and inner acoustic meatus could be visualized distinctly in each aspect, as for the microscope group, microscopic operation could be accomplished directly. The damage extents of facial nerve and inner acoustic meatus were compared between two groups.

Total removal of acoustic neuroma and conservation of facial nerve were achieved in all patients. For the neuroendoscope-assisted group, the postoperative facial functions were Grade I (n = 6), Grade II (n = 10) and Grade III (n = 4). Internal acoustic canal was drilled 2-3 mm in 4 patients and no drilling in others. For the microscope group, Grade I (n = 5), Grade II (n = 6), Grade III (n = 8) and Grade III-IV (n = 3). Internal acoustic canal was drilled at least 3 mm in 12 patients and no drilling in others. No complication such as cerebrospinal fluid leakage occurred during the follow-ups.

Endosocopic operation of acoustic neuroma surgery is superior to microscopic operation in terms of magnification, illumination, wide-angel and angulation. And the former procedure may yield better outcomes through alleviating the damage of facial nerve and decreasing the drilling degree of inner acoustic meatus.