Although neurosurgeons often prefer the retromastoid approach for resection of acoustic tumors, the translab approach does have special and useful indications. Let's go ahead and review the case of the 35 year old male with progressive growth of his acoustic tumor. Relatively small with significant functional hearing loss. This patient underwent a translab approach based on the preference of our ENT colleagues. An incision relative to the mastoid tip and the ear is illustrated. Following completion of the incision and reflection of the scalp flap anteriorly, a mastoidectomy and labyrinthectomy was completed by my ENT colleague. Here you can see the sigmoid sinus. Bone removal continues through the antrum. The fallopian tube is left intact. The presigmoid dura is exposed. The Trautman's triangle is un-roofed. Drilling continues. Here you can see the dura of the middle fossa. Here is the continuation of the labyrinthectomy. Here are the semicircular canals that are being removed. Bone removal continues until the internal auditory canal is skeletonized. Here, you can see the canal un-roofed both superiorly, inferiorly and posteriorly. The tumor is apparent through the dura. A diamond drill bit is used for removal of the thin shell of bone over the canal. This case the tumor was apparent. Here is the extent of presigmoid dura that has been exposed. We continue with a curvilinear incision within the dura, in order to expose the intradural contents. There is a variety of ways to open the dura in this case. Here is curvilinear incision, starting in the ear, just above the tubercle, jugular tubercle, and continuing superiorly. Incision is teed off laterally. You can see the tumor entering the IAC. The trigeminal nerve is identified and protected. Next, the tumor is de-bulked. You can see the medial capsule on the tumor. There's a nice arachnoid band between the capsule of the tumor and the intradural contents. After the tumor is de-bulked, it is rolled laterally. Aggressive de-bulking is the key maneuver for efficient and safe removal of the tumor, while avoiding traction injury on the surrounding neurovascular structures. The nerves are identified early. More specifically, the facial nerve is identified, as you can see, more anteriorly. Slightly grayish as compared to the vestibular nerve. The tumor is again, rolled laterally, de-bulked and then further mobilized away from the nerves. Obviously, the branch of the vestibular nerve affected by the tumor is transected and the last piece of tumor is removed through the IAC. You can see the facial nerve is intact posteriorly. All the ear cells are waxed and the postoperative MRI and CT scans demonstrate adequate removal of the tumor with presence of the fat within the epidural space. Thank you.
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