The most common indications for this approach are repair of superior semicircular canal dehiscence and approach to the IAC for acoustic neuroma resections. Usually small, intracanalicular tumors with good hearing are approached via this route. Vestibular nerve section and total facial nerve decompression, CSF leak, and meningocele repair are other less common indications for this approach. There is significant temporal lobe retraction during this approach, so this makes it less suitable for older patients.

For the middle fossa approach, the surgeon sits at the head of the table, the patient is in supine position, and the head is rotated to the contralateral side. A skin incision starting anterior to the tragus (preauricular crease) and extending superiorly to the parietal suture in a straight line or lazy-S configuration is performed (Fig. 13.1).

The temporalis muscle can be incised to create a rotational flap permitting its use for subcranial reconstruction as shown in Fig. 13.1. Alternatively, a vertical linear incision can be made and retracted to expose the skull directly below. An approximately 4 × 6-cm (or larger) craniotomy is performed.

If the temproal bone is well pneumatized and air cells are exposed during this apporach they must be obliterated with bone wax at the end of the case to minimize the risk of a post-operative cerebrospinal fluid leak.