Stapedotomy for Otosclerosis
Overview and Surgical Approach
Stapedotomy is the preferred surgical technique for treating otosclerosis due to its superior safety profile and excellent long-term hearing outcomes compared to alternative procedures. Stapedotomy involves creating a small hole in the stapes footplate and inserting a prosthesis to restore sound transmission to the inner ear.
Diagnosis and Patient Selection
Diagnosis of otosclerosis should be confirmed through:
- Conductive hearing loss on audiometry
- Absent stapedial reflexes
- Normal tympanic membrane
- High-resolution CT scan of temporal bones to confirm otosclerosis and rule out other pathologies
Ideal candidates for stapedotomy:
- Patients with progressive conductive hearing loss due to otosclerosis
- Air-bone gap >20 dB
- Good cochlear reserve (speech discrimination)
- No active middle ear infection
Surgical Technique
The stapedotomy procedure typically involves:
- Approach: Transcanal approach through the ear canal
- Exposure: Elevation of tympanomeatal flap to access the middle ear
- Assessment: Confirmation of stapes fixation through palpation
- Separation: Division of the incudostapedial joint and stapedial tendon
- Removal: Fracture of the stapes superstructure while preserving the footplate
- Fenestration: Creation of a small hole (0.4-0.8mm) in the stapes footplate
- Reconstruction: Placement of a prosthesis between the incus and the fenestration
- Sealing: Often using a vein graft or fascia around the prosthesis to prevent perilymph leakage
Outcomes and Effectiveness
Stapedotomy demonstrates excellent long-term results:
- Closure of air-bone gap to within 10 dB in approximately 94.2% of cases 1
- Mean four-frequency postoperative air-bone gap of 1.7 dB compared to 25.6 dB preoperatively 1
- Low risk of significant sensorineural hearing loss (0.5%) 1
- Better high-frequency hearing preservation compared to stapedectomy 2
- Long-term hearing results remain stable, with deterioration not exceeding normal age-related hearing loss 1
Stapedotomy vs. Stapedectomy
Stapedotomy is superior to stapedectomy for several reasons:
- Better preservation of high-frequency hearing 2, 3
- Lower risk of inner ear damage and sensorineural hearing loss 2
- Lower incidence of postoperative complications
- No cases of anacusis (complete hearing loss) reported after stapedotomy, compared to 1.7% after stapedectomy 2
Special Considerations
Challenging Cases
Obliterative otosclerosis: More technically demanding but still achieves closure of air-bone gap to within 10 dB in 95% of cases, though with slightly higher risk (4.8%) of sensorineural hearing loss 1
Malleus ankylosis: More challenging with lower success rates (64.7% achieve air-bone gap closure within 10 dB) 1
Very far-advanced otosclerosis: Consider stapedotomy as initial treatment due to being simpler, safer, and less costly than cochlear implantation. If stapedotomy fails to provide adequate hearing, cochlear implantation remains an option 4
Age Considerations
Elderly patients (>65 years): Similar success rates to general population (94.5% achieve air-bone gap closure within 10 dB) 1
Pediatric patients (≤18 years): Comparable results to adults (93.5% achieve air-bone gap closure within 10 dB) with no increased risk of complications 1
Postoperative Care and Follow-up
- Avoid water in the ear canal for 2-3 weeks
- Avoid nose blowing, heavy lifting, and air travel for 1-2 weeks
- Audiometric evaluation at 4-6 weeks postoperatively
- Long-term follow-up annually to monitor hearing outcomes
Potential Complications
- Taste disturbance (chorda tympani nerve injury)
- Tinnitus (usually temporary)
- Vertigo (usually transient)
- Perilymph fistula
- Sensorineural hearing loss (rare, 0.5% risk) 1
- Prosthesis displacement
Alternative Techniques
While some alternative techniques have been explored (such as posterior crus stapedectomy without prosthesis 5), stapedotomy with prosthesis insertion remains the gold standard due to its consistently superior outcomes and lower complication rates.