Facial Nerve Paralysis in Keratosis Obturans: A Systematic Review of Clinical Patterns, Management Outcomes, and Prognostic Insights.
Objective: This review consolidates all reported cases of facial nerve paralysis (FNP) complicating keratosis obturans (KO), a rare disorder characterized by keratin accumulation in the external auditory canal. The study aims to analyze clinical patterns, diagnostic findings, management outcomes, and prognostic factors to enhance understanding and guide evidence-based management of this underrecognized complication.
Methods: A comprehensive literature search of PubMed, Web of Science, Scopus, and Google Scholar (inception-December 2024) identified English-language case reports and observational studies linking KO to FNP. Two reviewers independently screened titles/abstracts, performed full-text assessments, and extracted data on demographics, clinical features, imaging, interventions, and outcomes.
Results: Seven cases (mean age: 32.4 years; 57.1% female) were analyzed. All exhibited left-sided FNP, with House-Brackmann grades III to VI at presentation. Hearing loss (71.4%) and keratin debris on otoscopy (71.4%) were common. High-resolution computed tomography (HRCT) revealed bony erosion (28.6%-57.1%) and soft-tissue involvement (57.1%). Surgical intervention (85.7%), primarily debridement or mastoidectomy, resulted in complete/partial FNP recovery in 85.7% of cases, while conservative management (14.3%) also showed improvement. Limitations of this review included the small number of cases, heterogeneity in management approaches, and lack of standardized outcome measures.
Conclusions: KO-related FNP, though rare, carries significant morbidity. Timely surgical decompression or conservative care may reverse neural injury, emphasizing early diagnosis via clinical-radiological correlation. The predominance of left-sided involvement and favorable outcomes postintervention warrant further investigation. Prospective studies are needed to establish standardized protocols and validate these findings in larger cohorts.