Pneumolabyrinth
Description
● Introduction:
• Definition: Air in the vestibule, semicircular canals, or cochlea.
• Taken into account radiographic evidence of a perilymphatic fistula (PLF).
•PLF = improper connection between the inner ear and the air-filled middle ear → perilymph leakage.
• Seldom seen: There are only around 14 documented instances of pneumolabyrinth following a temporal bone fracture.
First description: Nurre (1988, trauma-related); Mafee (1984, radiology).
● Causes and Aetiology
➣ Temporal bone fractures (transverse > longitudinal > mixed) are a result of trauma.
➣ Trauma caused by abrupt changes in pressure (diving, flying, blast damage) is known as barotrauma.
➣Otologic surgery includes mastoid, cochlear, and stapes surgeries.
● Classification
➣Air in the vestibule and semicircular canals is known as vestibular pneumolabyrinth.
➣Air in the cochlea alone is known as the cochlear pneumolabyrinth.
➣Combined pneumolabyrinth: Air in the cochlea and vestibular system.
(In the literature: isolated cochlear = uncommon, vestibular 71%, mixed 29%).
●Clinical Features
➣Hearing loss (100% cases): typically sensorineural, occasionally mixed.
➣ Symptoms of vasectomy
• Unbalance, vertigo, and nystagmus that happens on its own.
• Severe, incapacitating vomiting.
➣Additional symptoms include hemotympanum, auditory fullness, tinnitus (33%), and otorrhagia (ear haemorrhage).
➣The patient in this case is a 31-year-old woman who had a left-sided hearing loss after receiving RTA.
Severe nausea and vertigo.
• Ear bleeding.
• Otoscopy: hemotympanum + canal lacerations.
• Audiogram: HL that is mild to profoundly mixed.
● Examining:
➣ Pre-op → mild to deep HL (95 dB AC, 55 dB BC) is measured using Pure Tone Audiometry (PTA).
• Improvements were made after surgery, particularly at low frequencies (48 dB AC, 40 dB BC).
➣ The gold standard, high-resolution CT temporal bone:
• Inside the labyrinth, the air is seen as black foci.
• Identifies the kind of temporal bone fracture and the air source.
• Longitudinal fracture, vestibule air, and basal cochlear turn were the case findings.
➣ MRI: useless (no signal due to air and bone).
➣ Additional tests (not always performed): vestibular function tests, ECOG, and ABR.
● Case-specific intraoperative findings
• Following an unsuccessful conservative attempt, an exploratory tympanotomy was performed.
• The ossicular chain remains whole.
• The staples are positioned normally and are not subluxated.
• There was a perilymph leak due to a small fracture in the footplate (anterior crus).
• A fat graft from the ear lobule sealed the oval window.
● Literature Review and Discussion
➣Demographics: Mean age = 25 years (range 2–85), M:F = 14:1.
➣Type of fracture:
•Mixed (13%), longitudinal (20%), and transverse (67%).
Vestibular (71%), vestibular + cochlea (29%), and cochlear only (0%), are the three pneumolabyrinth sites.
➣Frequency of symptoms:
• 100% hearing loss.
• 73% of people have vertigo.
Tinnitus is 33%.
Results of treatment: Vestibular symptoms often go away as a result of air absorption or vestibular compensation.
• The variable for hearing outcomes might get better, become worse, or stay the same.
●Prognosis: either treatment typically resolves vasomotor symptoms.
➣Hearing: • The prognosis is worse if air gets into the cochlea (irreversible SNHL).
According to Kobayashi et al.'s experimental research, air in the scala vestibuli causes significant, permanent SNHL, whereas air in the scala tympani causes reversible impairment.
➣Case result: Hearing → partial but notable improvement in low frequencies; Vestibular symptoms → resolved after surgery.
Protocol
● Administration:
➣Conservative in 50% of cases:
• Head elevation and bed rest.
• Intravenous corticosteroids, which lower inflammation.
Prevent meningitis by using antibiotics.
• Regular CT monitoring.
•Suggested if: no increasing vestibular indications, steady hearing, and moderate symptoms.
➣In 50% of patients, surgery consists of exploratory tympanotomy with fistula closure (round or oval window).
• Materials for grafting: muscle, fat, and fascia.
It is recommended if there is a suspected perilymphatic fistula that has been present for more than seven days (risk of meningitis), persistent or severe vertigo, or progressive hearing loss.
➣Case outcome: Surgery results in progressive hearing recovery and quick vestibular symptom alleviation.
●Difficulties Met
➣Hearing Loss and Vertigo: Acute symptoms including nystagmus, severe vertigo, and abrupt hearing loss can be brought on by air entering the inner ear.
➣worry and Imbalance: The patient frequently feels a great deal of worry because of the abrupt loss of hearing and disequilibrium.
➣danger of Infection: A connection between the external environment and the typically sterile inner ear increases the danger of meningitis or other infections.
➣Potential for Additional Injury: Falls and other injuries may become more likely if vertigo persists.
● Nursing Management and Interventions:
➣Evaluation and Tracking:
• Regularly check neurological state for any deteriorating symptoms, such as focused deficits or increasing confusion.
• Use common bedside tests to determine the extent of hearing loss and record vestibular symptoms, such as nausea, vertigo, and balance issues.
➣Fall Precautions:
• Because of the extreme vertigo and unbalance, take extra care to prevent falls.
• Until the vertigo goes away, keep the bed rails in place, help the patient walk, and make sure they stay away from tasks that need coordination.
➣ Positioning:
• To possibly lessen perilymph leakage or air movement, place the patient with the afflicted ear up.
• During acute treatment, promote bed rest as advised.
➣ Preventing Infection:
• Keep an eye out for symptoms of meningitis or ear discharge, such as fever or stiff neck.
•When doing any necessary ear operations, use aseptic method.
Notes
For more details visit 10.2147/IMCRJ.S66421
