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Published on: February 29, 2020
Case report: Perilymphatic fistula from a round window microfissure
Toru Seo1, Arata Kemmochi1, Yosuke Koike1
1Department of Otolaryngology, Yokohama Seibu Hospital, St. Marianna University School of Medicine, Yokohama, Japan.
Abstract:
A microfissure near the round window niche is an anatomical structure that communicates between middle ear and the ampulla of the posterior semicircular canal. It has been suggested that the microfissure can cause inner ear symptoms; however, the etiology has not yet been confirmed clinically. We report, to our knowledge, the first case of microfissure with complaint of hearing loss and vertigo and improvement in hearing after surgical sealing of the microfissure. A 50-year-old man complained of hearing disturbance, tinnitus with flowing-water sound in the left ear, and a floating sensation upon pushing the left tragus. He had moderate sensorineural hearing loss (43.3 dB) in the left ear for 3 days. His hearing worsened and he complained of severe vertigo. An exploratory tympanotomy was performed 8 days after onset. A microfissure and accumulation of clear fluid in the floor of the round window niche were detected, and leakage point was packed with connective tissue. One month after surgery, his hearing (20.0 dB) and disequilibrium had improved. The inner ear symptoms improved after the surgery in this case, suggesting that the microfissure might have caused the symptoms.
Insights
A rare microfissure near the round window niche can cause hearing loss and vertigo. Surgical sealing of this microfissure led to significant improvement in a patient's hearing and balance.
Area of Science:
- Otolaryngology
- Neuroscience
- Anatomy
Background:
- A microfissure near the round window niche is an anatomical communication between the middle ear and the posterior semicircular canal.
- The clinical etiology of inner ear symptoms attributed to such microfissures remains unconfirmed.
Observation:
- A 50-year-old male presented with hearing disturbance, tinnitus, and vertigo.
- The patient exhibited moderate sensorineural hearing loss and worsening vertigo, suggestive of inner ear pathology.
- Exploratory tympanotomy revealed a microfissure and fluid accumulation in the round window niche.
Findings:
- Surgical packing of the microfissure with connective tissue was performed.
- Postoperatively, the patient experienced significant improvement in hearing and a reduction in vertigo.
- Hearing improved from 43.3 dB to 20.0 dB, and disequilibrium resolved.
Implications:
- This case suggests a potential clinical link between microfissures near the round window niche and inner ear symptoms.
- Surgical intervention, specifically sealing the microfissure, may effectively treat associated hearing loss and vertigo.
- Further clinical investigation is warranted to confirm the role of these microfissures in audiovestibular disorders.
