The Middle Fossa Approach and Extended Middle Fossa Approach: Technique and Operative Nuances

BACKGROUND: The middle fossa approach and extended middle fossa approach, also known as the anterior transpetrosal approach, are cranial base techniques for addressing small vestibular schwannomas, medial temporal bone lesions, midbasilar trunk aneurysms, and selected petroclival lesions. OBJECTIVE: To provide an outline of a number of technical nuances that are important to correct application of these approaches, maximizing exposure, and limiting potential morbidity. METHODS: Via a temporal craniotomy, the petrous apex is removed in variable degrees, depending on the exposure requirements of the lesion. The technique is described in detail with appropriate nuances of the technique provided. RESULTS: The described nuances of technique in the performance of the approaches have resulted in successful application of these techniques in a significant number of cases. CONCLUSION: Significant familiarity and practice with these surgical approach techniques are critical to applying them safely to clinical problems. A number of technical details can assist the surgeon in achieving optimal exposure and limited morbidity.