Diagnostic criteria of barotraumatic perilymph fistula based on clinical manifestations

Assessing the efficacy of perilymphatic fistula repair surgery in alleviating vestibular symptoms and associated auditory impairments

Perilymph Fistula (PLF), abnormal communication between the fluid-filled space of the inner ear and the air-filled space of the middle ear, is a significant cause of vestibular and auditory symptoms. This is a retrospective study of 22 cases treated with PLF repair surgery, selected based on our surgical indication. We analyzed the characteristics of these 22 cases and evaluated the efficacy of PLF repair surgery in treating vestibular and auditory symptoms. Cases with antecedent events had significantly shorter intervals before surgery. The postoperative recovery from vestibular symptoms following PLF repair surgery was strikingly rapid, with 82% of cases demonstrating marked improvement within a week, even in chronic cases. Despite the notable absence of a control group in the study, the marked improvements in vestibular symptoms and substantial reductions in Dizziness Handicap Inventory (DHI) scores suggest that the observed benefits are attributable to the surgical intervention. Further, timely surgery showed improvements in hearing, with some benefits also seen in late-stage surgeries. Using the perilymph-specific protein Cochlin-tomoprotein (CTP) as a diagnostic biomarker, we could prove that PLF could be responsible for disequilibrium and related auditory disturbances in these patients. A new hypothesis is proposed that the chronic disequilibrium experienced by many PLF patients is due to enhanced mobility of the utricle and not to endolymphatic hydrops. Further research is needed to fully elucidate PLF's symptoms and treatment efficacy using the surgical indication we developed.

Sneeze-induced pneumolabyrinth 15 years after stapedotomy

Pneumolabyrinth refers to the presence of air within the inner ear and is a fairly common occurrence immediately after stapes surgery, but rarely occurs in a delayed manner years after the initial operation. We present a case of a patient with a history of left stapedotomy 15 years prior, who presented with acute onset vertigo, tinnitus and hearing loss in her operated ear. Her symptoms were preceded by an upper respiratory tract infection associated with bouts of sneezing. Examination revealed a spontaneous right beating nystagmus and positive head thrust to the left. Pure tone audiometry demonstrated a left mixed hearing loss which subsequently deteriorated to a profound sensorineural hearing loss. CT showed the presence of air within the left vestibule and semicircular canals. The patient underwent an exploratory tympanotomy and repair of perilymphatic leak with resolution of vestibular symptoms but no improvement in sensorineural hearing thresholds.

Significance of Pseudo-Conductive Hearing Loss and Positional Nystagmus for Perilymphatic Fistula: Are They Related to Third-Window Effects?

Objectives

Patients’ clinical presentation is critical for identifying suspected perilymphatic fistula (PLF). The involvement of third-window lesions in the pathomechanism of PLF has been hypothesized. This study investigated the clinical features of PLF and the relationship of the third-window effect with PLF.

Methods

Sixty patients underwent surgical exploration for suspected PLF and the oval and round windows were reinforced. Clinical features including demographics, pure-tone audiometry (PTA), and videonystagmography were evaluated preoperatively and 1 month postoperatively. Surgical outcomes were analyzed according to the improvement of hearing and vestibular symptoms and signs. The conductive components of PTA (air-bone gap [ABG]) were measured, and the relationship between ABG closure after surgery and hearing improvement was analyzed. In addition, postoperative subjective dizziness was assessed by clinical interviews. Changes in positional nystagmus were analyzed according to ABG closure and hearing improvement.

Results

ABG at lower frequencies (LFABG; 250 Hz, 500 Hz, 1,000 Hz) was present in 27 patients (45%). Postoperatively, PTA significantly improved after surgical repair. Among the patients with preoperative LFABG (n=27), 15 (55.5%) showed postoperative ABG closure and significant improvement in PTA at all frequencies compared with the patients without ABG closure (P=0.012). Subjective dizziness improved in 57 patients (93.3%). Positional nystagmus was found in 45 of 49 patients. Multiple canal involvement was more common than single canal involvement (67% vs. 33%). The horizontal semicircular canal was most commonly involved, followed by the posterior and anterior canals. Postoperatively, positional nystagmus disappeared, or the number of involved canals decreased in 22 of 34 patients (64.7%).

Conclusion

Pseudo-conductive hearing loss at lower frequencies and positional nystagmus originating from multiple semicircular canals were common findings in PLF. Surgical reinforcement of the oval and round windows improved the hearing threshold accompanied by closure of ABG. A third-window lesion might explain these clinical features of PLF.

CT and MRI for the diagnosis of perilymphatic fistula: a study of 17 surgically confirmed patients

BACKGROUND

We evaluated the usefulness of CT and MRI for the diagnosis of perilymphatic fistula (PLF) of the round (RW) and/or oval (OW) windows, with surgery as gold standard.

METHODS

We retrospectively enrolled 17 patients who presented a surgically confirmed PLF of the round (RW) or oval (OW) windows. All patients were imaged by CT + MRI (T2W SSFP without contrast) prior to surgery (= gold standard). Two radiologists, analyzed the RW and OW on the side of the clinical symptoms and sensitivity (Se) + Specificity (Sp) were calculated.

RESULTS

Round window fistula was the most frequent (71%). The best sign of PLF on imaging was a fluid filling of the window niches, which had good Se (83-100% for RW, 66-83% for OW) and Sp (60% for RW, 91-100% for OW). Disorientation of the footplate and pneumolabyrinth were also only observed in 50% of OW PLF.

CONCLUSION

The combination of CT and MRI is a reliable tool for a fast and accurate diagnosis of round and oval window perilymphatic fistula, with good sensitivity (> 80%). The most common sign of PLF on imaging is the presence of a fluid-filling in the RW (especially if > 2/3 of the RW niche) or in the OW niches on both CT and MRI. A disorientation of the footplate or the presence of a pneumolabyrinth are clearly in favor of an oval window perilymphatic fistula.

Prognostic factors regarding the hearing outcome in severe to profound sudden sensorineural hearing loss treated by tympanotomy and sealing of labyrinthine windows after ineffective systemic corticosteroid application

PURPOSE

Tympanotomy and sealing of labyrinthine membranes has become in some centers used to treat severe to profound sudden sensorineural hearing loss refractory to conservative treatment. The aim of this retrospective study was to determine which preoperative factors influence the likelihood of postoperative recovery according to different audiological assessment criteria.

METHODS

The mean final hearing threshold, the hearing improvement, the probability of a complete recovery according to two different classifications, and probability of a significant recovery of 136 adult subjects were studied by univariate and multivariate analyses.

RESULTS

The subject's mean postoperative 4-pure-tone-average was 63.9 ± 35.9 dB, the mean improvement was 42.8 ± 32.6 dB. Depending on the classification system used, 18.4-28.0% of subjects experienced a complete recovery. 77.2% of subjects had a significant hearing improvement. History of a pressure change (odds ratio (OR):4.6) was the only positive prognostic factor for hearing improvement. It also enhanced probability of experiencing a complete hearing recovery (OR: 2.8-6.3). Preoperative total deafness (OR: 1.5-1.9) and vertigo (OR: 3.3-4.6) were negative prognostic factors for the mean final hearing threshold and the probability of a complete hearing recovery. Patients with a preceding pressure change event achieved a complete recovery in 45.5-50.0%, those without such an event recovered completely only in 13.2-23.7%.

CONCLUSION

Evaluating prognostic factors and the rate of complete hearing recovery are influenced by the underlying assessment parameters. In addition to the mean postoperative hearing threshold and hearing gain, the probability of regaining a serviceable hearing is clinically important for the individual and should be added to the assessment criteria in future studies.