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.

Surgical Outcomes on Hearing and Vestibular Symptoms in Barotraumatic Perilymphatic Fistula.

OBJECTIVE: To analyze surgical results on hearing and vestibular symptoms in patients with barotraumatic perilymphatic fistula (PLF) according to diagnostic criteria. METHODS: A total of 39 patients (41 ears) who underwent surgery on suspicion of barotraumatic PLF from January 2005 to December 2017 were included. Pure tone audiometry and videonystagmography (VNG) recording for spontaneous nystagmus and positional tests were performed preoperatively and postoperatively at 1 week and 1 month. Surgical outcomes were analyzed based on hearing results, subjective dizziness, and change of nystagmus. RESULTS: Preoperative hearing level was 75.5 ±â€Š28.7 dB for definite PLF and 88.5 ±â€Š22.8 dB for probable PLF, and levels were not significantly different between groups. Preoperatively, subjective dizziness was present in 18 (94.7%) and 19 (95%) in each group. Among 39 patients, 24 had VNG recordings. Positional nystagmus was recorded in 87.5% (7/8) and 87.5% (14/16) of the definite and probable PLF groups, respectively. Postoperatively, hearing was improved in 65% (13/20 ears) of definite PLF and 61.9% (13/21 ears) of probable PLF. There was no significant difference between the two groups. Hearing gain was significantly correlated with the time interval between symptom onset and surgical timing. Subjective dizziness was improved immediately after surgical repair in 97.4% (17/18) of definite PLF patients and 100% (19/19) of probable PLF patients. Even though dizziness was improved in most patients, some had persistent positional nystagmus and recurrent dizziness. CONCLUSIONS: Surgical sealing of both windows in suspected barotraumatic PLF is an effective treatment to improve hearing and subjective dizziness.

Traumatic stapes fracture with rotation and subluxation into the vestibule and pneumolabyrinth.

A 41-year-old man presented after forceful penetrating ear injury. He had incapacitating vestibular symptoms. Computed tomography revealed pneumolabyrinth with a fractured stapes that was >90 degrees rotated and subluxed into the vestibule, such that the crura and capitulum could be seen in the vestibule. Surgical repair reversed the vestibular symptoms, but there was persistent hearing loss. Stapes fractures are unusual and rarely associated with subluxation into the vestibule. When this does occur, there is usually simple footplate depression. This case demonstrates a rare stapes fracture with pneumolabyrinth and >90 degrees stapes rotation, then subluxation into the vestibule. Laryngoscope, 2009.

[Perilymphatic fistula: diagnosis and treatment]. / Przetoka perylimfatyczna jako problem diagnostyczny i leczniczy.

INTRODUCTION: Diagnosis and management of perilymphatic fistula (PLF) is a controversial topic in the international neurotologic literature. An illustrative case of post traumatic PLF with clear surgical indications is presented. This manuscript also reviews the various clinical presentations, pathogenesis, diagnostic examinations, and management options of PLF. MATERIALS AND METHODS: Case report and literature review. RESULTS: A 40 y/o female presented with paroxysmal vertigo, imbalance and severe sensorineural hearing loss (SNHL) following minor occipital head trauma from a fall six months prior to presentation. Laboratory examination included intermittently positive fistula sign on video-nystagmography. Patient failed to respond to trials of pharmacologic treatment and bedrest and ultimately underwent surgical exploration and repair. Patient had earlobe fat placed in the round and oval windows. Postoperatively, she had prompt resolution of vestibulopathy and ultimate full return of sensorineural function. CONCLUSIONS: Patients with appropriate antecedent history demonstrating fluctuating SNHL and vestibulopathy, failing to respond to conservative medical treatments, should be considered for exploratory tympanotomy. In the absence of any other violations of labyrinthine integrity, connective tissue grafting of the round and oval windows should be performed even if no obvious flow of fluid is observed. This management protocol is safe and effective in properly selected patients.

Rupture pressures of membranes in the ear.

The rupture pressures of the tympanic membrane, Reissner's membrane, the round window membrane, and the annular ligament have all been measured in cadaver ears from Norwegian cattle. For the tympanic membrane, a static overpressure was applied to the ear canal; for Reissner's membrane, to the endolymph; and for the round window membrane, to the perilymph. The rupture pressure of the annular ligament equals the rupture force to the footplate divided by the area of the oval window. The mean rupture pressures are 0.39 atm for the tympanic membrane, 0.047 atm for Reissner's membrane, greater than 2 atm for the round window membrane, and 29.4 atm for the annular ligament. This last pressure corresponds to 0.68 kilogram force applied to the footplate. The ruptures of the tympanic membrane appeared without exception as small tears in the pars flaccida. The rupture pressure of the tympanic membrane was also measured in a few ears from foxes.

The leaking labyrinthine lesion resulting from direct force through the auditory canal: report of five cases.

The leaking labyrinthine lesion is treated by conservative methods or surgical procedures. With respect to the stapes, the surgical treatment is controversial. Five cases of middle ear injuries accompanying oval window rupture are reported herein. In each case, direct force through the auditory canal damaged not only the ossicular chain but also the oval window. Initial symptoms were sudden hearing loss with significant conductive disturbance and various degrees of unsteadiness. Spontaneous horizontal nystagmus directed toward the uninvolved ear was observed in each case. Tympanic cavities were promptly explored under general anesthesia and oval window injuries were confirmed. In each case, the damaged stapes was temporally removed from the oval window. Perilymphatic leakage was recognized in each case. Two patients had subluxation of the stapes with a paucity leakage. Three had complete luxation of the stapes with a relatively huge oval window fistula. Disrupted oval windows were repaired with temporalis muscle fascial grafts that were inserted under the middle ear mucosae surrounding the oval windows. The stapes were replaced in the repaired oval windows, and the ossicular chains were reconstructed without artificial grafts. Vestibular dysfunctions disappeared within 7 days, and satisfactory audiologic results were obtained in each case.

[Traumatic perilymphatic fistula of round and oval windows (four cases reported)].

OBJECTIVE: To explore the diagnosis and treatment to traumatic perilymph fistula (PLF) of round and oval window. METHOD: Traumatic PLF was diagnosed by the traumatic history of head, neck and ear, the examinations of auditory and vestibular function, and the exploratory tympanotomy. The PLF of round and oval windows were repaired by fascia graft or tragus perichondrium and gelform. Four cases with traumatic PLF of round and oval window were reported in this paper, which included 2 cases hitten by hand, 1 by brick, 1 insulted by middle ear surgery. Exploratory tympanotomy was performed from one and half to nine months after injury. One case was misdiagnosed as Meniere's disease before confirming PLF. Exploration and repair of PLF underwent in all cases. RESULT: The symptom of vertigo relieved in all cases after surgery, while the hearing recovery was not evident. CONCLUSION: 1. Traumatic PLF is unrare, hence, traumatic PLF should be alerted if patients suffer from vertigo and hearing impairment after head and ear injury. 2. The features with vertigo attacks, fluctuating hearing loss and tinnutis should be distinguished from Meniere's disease. 3. Early exploratory tympanotomy and repair of PLF are effective for relieving vertigo and improving hearing.

Lightning and its effects on the auditory system.

Patients struck by lightning can present with a wide variety of unusual otologic problems including burns to the external auditory canal, tympanic membrane rupture, middle ear injury, and sensorineural hearing loss. Four patients who incurred various otologic problems, including one patient with previously unreported bilateral oval window fistulas following lightning injury, are presented. Audiologic, otologic, and surgical findings are reviewed as well as patient follow-up and outcome.

[Recurrence of perilymphatic fistula].

Recurrence of the perilymphatic fistula is not rare and may be a tough problem for surgical treatment. This is because a graft is usually applied on the ruptured window(s) from the middle ear and therefore the perilymphatic pressure directly acts on the graft. The recurrence may be caused by a technical failure, use of an unsuitable graft material, poor postoperative bedrest, trauma, increased inner ear pressure, etc. In our clinic, the recurrence occurred in 7 of 48 cases surgically treated. Vertigo accompanied with spontaneous or positional nystagmus was seen in all 7 recurrent cases, while only 2 of them complained of worsening of the existing hearing loss. Re-operation was carried out in two patients. In the first case, closure of the round window by the previous operation was found incomplete, and the perilymph leaked through the gap around the graft. In the second case, closure of the round window was complete, but perilymph leaked from the oval window. In order to prevent the recurrence, the operation should be carefully performed by using strong and adhesive tissue as a graft material, applying a glue between the graft and the inner ear window(s), and keeping strict postoperative bedrest.

Perilymph fistula: the Stanford experience.

Seventy-eight tympanotomies were performed to determine the presence of perilymph fistulas (PLFs); of these, 51% were found. The oval and round windows of all patients were grafted, whether PLFs were present or not. Of those patients with PLFs, 64% had resolution of their major symptom; when no PLF was found, 44% had a similar outcome. We concluded that 1) PLFs often behave as if they are epiphenomena in relation to hearing and balance, 2) PLFs can be intermittent, 3) PLF surgery is disappointing for restoration of hearing in sudden hearing loss when compared to the rate of spontaneous recovery, 4) stabilizing a fluctuating or progressive loss is a more realistic goal, and 5) establishing preoperative criteria for exploration is still a problem.

Pressure transmission properties from the externa ear canal to the inner ear. An experimental study using guinea pigs.

The inner ear pressure (PIE) in response to pressure changes in the external ear canal was measured in guinea pigs while alternatively opening and closing the perforation of the otic bulla. When the bulla was opened, only a transient degree of applied pressure was transmitted to the inner ear and the amplitude of the PIE was smaller than that of the corresponding PIE when the bulla was closed. This was because the applied pressure was exclusively transmitted to the inner ear via the ossicular chain. When the otic bulla was closed, the pressure was transmitted not only via the ossicular chain but also via the round window (RW) through the middle ear cavity. When the bulla was closed, the amplitude of PIE was larger by a positive pressure load than by the corresponding negative one. The amplitude of PIE showed a linear relationship to ear canal pressure of at least within the +/- 200 mmH2O range, as long as pressure was slowly applied to the ear canal. When the loading pressure was abruptly changed, a bouncing response, possibly reflecting elasticity of the RW, was evoked, which diminished or disappeared when the round window was artificially ruptured.

[The "window-fistula symptom" in lesions of the round and oval window]. / Das "Fenster-Fistelsymptom" bei Läsionen im Bereich des runden und ovalen Fensters.

22 tympanoscopies in suspected perilymph fistulas with clinical symptoms such as sudden hearing loss, tinnitus, vertigo, fluctuating hearing etc., histories and intraoperative findings were registered. In some cases a remarkable interval between the implicated event and the clinical manifestation of the symptoms was noticed. Besides on case history and audiometric data the diagnosis was based on vestibular investigations. In 14 of 22 cases the window-fistula-symptom was positive. The window-fistula-symptom is defined as a provocation nystagmus with maximal intensity in the lateral head position lying on the affected ear and in the head hanging position with the head rotated to the affected side. After abandoning these positions the nystagmus is decreased. Mostly the nystagmus is directed to the healthy side. With regard to the preoperative and postoperative findings a generous indication for tympanoscopy in suspected fistulas of the round and oval window membrane is recommended.

Labyrinthine membrane rupture caused by elevated intratympanic pressure during general anesthesia.

General anesthesia is not considered as a potential cause of hearing loss. However, three patients who sustained sensorineural hearing loss due to labyrinthine membrane rupture following general anesthesia with nitrous oxide have come to the authors' attention. These cases are presented and the mechanism causing labyrinthine membrane rupture is discussed.

Simultaneous round and oval window fistulae in a child.

Sudden hearing loss from simultaneous rupture of both oval and round windows, occurring in the only hearing ear of a child, is described. The condition was surgically managed with recovery of hearing. Of particular note was the presence of air aspirated into the labyrinth at the time of membrane rupture, which has not previously been described. The possible mechanisms and some clinical correlates associated with anatomic predisposition to such rupture are discussed.

Sudden hearing loss in divers and fliers.

Many papers have been written about sudden sensory hearing loss and the effect of barotrauma on the inner ear. Fistulae of the round and oval window membranes have been implicated in the great majority of these cases. It has usually been recommended that the patient be treated with conservative therapy, such as bed rest, for a period of as long as 30 days and that the final hearing results are as good or better than those that have been surgically explored and corrected. In our experience immediate surgical exploration and correction of sudden severe or profound sensorineural deafness in the diver or flier is absolutely essential and the excellent results of hearing improvement in this select group certainly corroborates this theory. Other cases with the hearing loss limited to the high frequencies most notably have tinnitus and surgical exploration does not improve the hearing but may improve vertigo if present. Numerous cases are presented to support these supositions.