Flexible Endoscope for IAC Control of Tumor Removal
Using a retrosigmoid approach, the internal auditory meatus cannot be completely opened to expose the fundus in order to preserve the superior and posterior semicircular canals. Therefore, a straight microscopic view cannot provide an adequate visualization of the most lateral part of the internal auditory canal (IAC). Endoscope assistance provides optimal exposure of the fundus of the IAC and improves the ability to evaluate the extent of resection intraoperatively. Our group reported the successful surgical treatment (total resection) of three cases of intracanalicular vestibular schwannomas operated on with an endoscopic-assisted retrosigmoid approach by means of a flexible endoscope (4-mm × 65-cm, Karl Storz, Inc.). The main advantage of the flexible endoscope is the possibility to orient the endoscopic tip directly into the IAC to obtain an optimal visualization of the fundus. As opposed to rigid devices, the flexible endoscope has to be manipulated with two hands. However, this limitation can be easily overcome through good cooperation and synchronicity between the operator and the assistant.
KeywordsVestibular schwannoma/retrosigmoid approach Vestibular schwannoma/endoscope Vestibular schwannoma/surgery
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