25
Surgical Treatment for Vertigo
Elizabeth H. Toh
Surgical treatment of vertigo is characteristically directed at peripheral vestibular disorders. The role of surgery is directly dependent on the nature of the pathology. Surgical treatment of these disorders can be directed at the specific part of the inner ear causing the dysfunction or at ablating inner ear function or dividing the afferent connections to the central nervous system. Chemical ablation of vestibular function is discussed in Chapter 26.
- As with most otologic problems, surgery should be considered only when medical management has failed to control the patient’s vestibular symptoms adequately.
- The choice of surgical intervention is predicated on the status of hearing in the involved and contralateral ear, vestibular function in the contralateral ear, physiologic age of the patient, and medical health of the patient.
- Nonablative options should be considered in bilateral disease to avoid the problem of oscillopsia.
- Patients with nonlocalizing pathology or an uncategorized vestibulopathy should not be considered candidates for surgical intervention.
- Preoperative vestibular testing is used to confirm the ear affected.
- This procedure is indicated for disabling positional vertigo resulting from canalithiasis involving the posterior semicircular canal despite multiple attempts at particle repositioning maneuvers.
- The procedure is performed under general anesthesia, with standard prep and drape for postauricular surgery.
- Intraoperative facial nerve monitoring is not routinely used.
- Perioperative antibiotics are administered in patients with prior otitis media.
- Through a standard postauricular incision, a limited mastoidectomy is performed for exposure of the mastoid antrum and lateral semicircular canal. The spine of Henle laterally guides the surgeon to the approximate location of the lateral semicircular canal. In the case of a sclerotic mastoid, always stay close to the posterior bony external auditory canal, and proceed anterosuperiorly along the mastoid tegmen to avoid injury to an anteriorly placed sigmoid sinus.
- The posterior semicircular canal is located posterior to and at a 90 degree angle to the lateral canal. The superior semicircular canal is located at a deeper plane relative to these two canals and is generally not encountered during this procedure. Air cells surrounding the posterior semicircular canal are removed using a 3 or 4 mm diamond bur.
- The area to be exposed for occlusion is below the level of the lateral semicircular canal. A small diamond drill bur is used to thin the bone of the bony otic capsule encasing the membranous portion of the vestibular labyrinth to eggshell thickness over a 180 degree circumference, creating a 1 × 3 mm bony fenestrum.
- The remaining eggshell of bone is then carefully removed using a sharp 90 degree pick.
- Avoid suctioning over the membranous labyrinth to minimize the risk of sensorineural hearing loss. Any perilymph or irrigation fluid should be wicked away using a small cottonoid.
- The lumen of the posterior semicircular canal is then occluded with a plug of bone wax or bone pate collected at the time of mastoidectomy. This effectively occludes the membranous endolymphatic space, precluding the possibility of otoconia drifting within this compartment. The advantage of using bone pate is subsequent ossification of the canal, ensuring permanent canal occlusion.
- The fenestrum, along with the plug, is then covered with a piece of temporalis muscle or fascia, held in place with Surgicel® or Tisseal® (human fibrinogen glue).
- The postauricular incision is closed in two layers, and a mastoid dressing is applied over the ear for 24 hours.
- Postoperative dizziness, disequilibrium, or motion sensitivity may necessitate hospitalization until the patient is able to ambulate. Early vestibular rehabilitation is indicated in patients with residual vestibular symptoms.
There are three surgical procedures used for control of vertigo in Meniere’s disease if medical therapy has failed. They are endolymphatic sac procedures, vestibular nerve section, and labyrinthectomy.
- Labyrinthectomy is reserved for patients with no useful hearing in the affected ear.
- Caution should be exercised in offering vestibular nerve section and labyrinthectomy for patients with bilateral disease.
