Underwater endoscopic ear surgery: A systematic review.

PURPOSE: To evaluate the clinical indications, surgical techniques, audiological outcomes, operative efficiency, and safety of underwater endoscopic ear surgery (UWEES).

METHODS

A comprehensive literature search was conducted through 14 May 2025 using PubMed, Google Scholar, and the Cochrane Library. Keywords included "endoscopic ear surgery," "underwater ear surgery," and "endoscopic underwater ear surgery." Original English-language studies involving UWEES in human subjects (≥ 3 patients) were included. Studies using microscopes or conducted in animals were excluded. Data extraction and quality assessment were performed independently by two reviewers, following PRISMA guidelines and using the NIH tool for risk of bias in case series. A qualitative synthesis was conducted due to heterogeneity in study designs and outcomes.

RESULTS

Nine studies met inclusion criteria. UWEES was applied across five principal indications: canaloplasty, attic cholesteatoma, cholesteatoma involving the mastoid, labyrinthine fistula repair, and superior semicircular canal dehiscence (SCDS) plugging. Across all studies, sensorineural hearing was preserved, with significant improvements in air-bone gap closure. Operative time was reduced compared to traditional methods. UWEES was associated with low complication rates and effective resolution of vestibular symptoms in > 90% of cases.

CONCLUSIONS

UWEES is a safe, effective, and minimally invasive technique offering enhanced surgical visualization, improved hearing outcomes, and better inner ear preservation. Further prospective, high-quality studies are needed to validate their long-term efficacy and establish standardized protocols.