Middle Cranial Fossa Approach to Repair Tegmen Dehiscence Using Self-setting Calcium Phosphate Cement: A Retrospective Case Review

Complications of Cholesteatoma

Complications of cholesteatoma result from characteristic inflammatory and resorptive processes that erode the structures of the middle and inner ear with potential to spread locally. Common intratemporal complications include hearing loss, facial nerve palsy, labyrinthine fistula, and dysgeusia. Extratemporal complications, though less common, may be life-threatening, and include cerebrospinal fluid leak and encephalocele, meningitis, epidural and intraparenchymal abscesses, subdural empyema, and otic hydrocephalus.

Hydroxyapatite Use in Repair of Lateral Skull Base CSF Leaks Via Transmastoid Approach: When Does It Work?

OBJECTIVE

The objective of this study is to evaluate the efficacy and outcomes of using a transmastoid approach with hydroxyapatite cement to repair lateral skull base cerebrospinal fluid (CSF) leaks.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary-level care hospital.

PATIENTS

Surgical patients 18 years or older between 2013 and 2022 with spontaneous CSF leak.

INTERVENTIONS

Trans-mastoid approach for skull base repair using hydroxyapatite cement.

MAIN OUTCOME MEASURES

Failure rate of repair; location and size of defect, patient demographic factors.

RESULTS

Of the 60 total defects (55 patients, 5 bilateral repairs) that underwent CSF leak repair using hydroxyapatite cement, the success rate was 91.66% (55 successful repairs). The average defect size in unsuccessful repairs was 1.15 cm compared with 0.71 cm for successful repairs. In addition, 80% (4/5) of the failed repairs were in the tegmen tympani region. Higher failure rate was noted in women (3/5) and in former smokers (4/5). Average time to recurrent symptoms was 1.75 years in the failed repair cohort. Of the patients with failed repairs, 4/5 were prescribed acetazolamide before their second procedure with successful second repair. In addition, five patients experienced postoperative headaches, three (5.4%) of whom required placement of VP shunts to relieve increased intracranial pressure. Two patients (3.6%) had complications of either infection or hearing loss.

CONCLUSIONS

Transmastoid approach utilizing hydroxyapatite is a successful approach for CSF leak repair, with a low complication and failure rate. Women, prior smoking history, and larger defects in the tegmen tympani region may need alternative materials or approach for repair. Long follow-up is warranted as recurrence of symptoms might be delayed. In cases of benign intracranial hypertension, adjuvant treatment with either acetazolamide or VP shunt placement may prevent failures.