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Perilymphatic Fistula of the Round Window European Annals of Otorhinolaryngology, Head and Neck diseases (2011) 128, 139—141 View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector CASE REPORT Perilymphatic fistula of the round window M. Al Felasi a, G. Pierre a, M. Mondain a,b, A. Uziel a,b, F. Venail a,∗,b a Service ORL et centre d’implantation cochléaire, CHU Gui-de-Chauliac, 80, avenue Augustin-Fliche, 34295 Montpellier cedex 5, France b Inserm U583, physiopathologie des déficits sensoriels et moteurs, institut des neurosciences de Montpellier, hôpital Saint-Eloi, bâtiment INM, 80, rue Augustin-Fliche, BP 74103, 34091 Montpellier cedex 5, France Available online 1 February 2011 KEYWORDS Summary Perilymphatic fistula; Objective: To highlight diagnostic and treatment pitfalls in perilymphatic fistula. Fistula sign; Case reports: Two cases of round-window fistula are reported, detailing clinical aspect, treat- Round window ment and outcome. The triad comprising sensorineural hearing loss, tinnitus and vertigo with associated fistula sign is classical but in fact rarely encountered. Imaging is of limited contri- bution, but may reveal anatomic abnormalities suggestive of perilymphatic fistula. Outcome is improved by early management, especially in case of moderate hearing loss. Discussion/conclusion: Diagnosis of perilymphatic fistula is challenging, but enables effective treatment. On any suspicion, surgical exploration should be undertaken, being the only reliable guide to diagnosis and etiologically adapted management. © 2011 Elsevier Masson SAS. All rights reserved. Introduction Case reports Spontaneous perilymphatic fistula without associated cra- Case 1 nial trauma results from membranous labyrinth rupture, generally at the oval window and round-window membrane, A 43-year-old man consulted for hearing loss, vertigo and without temporal bone fracture [1]. We present two cases tinnitus following a slap to the right ear. Initial examina- of round window perilymphatic fistula secondary to sud- tion had found a perforated eardrum with mixed hearing den pressure change, including treatment and medium-term loss and right vestibular deficit, treated by betahistine and outcome. The issues of early management and means of acetyl-leucine. He was referred to our department 3 weeks diagnosis are discussed. after the initial trauma, due to persistent positional vertigo, progressive hearing loss and tinnitus. Examination found an intact eardrum with perceptive hearing loss (Fig. 1). There was no nystagmus on videonystagmoscopy and fistula sign was negative. CT simply showed an aspect compatible with posterior dislocation of the stapedial footplate (Fig. 2). ∗ Corresponding author. Tel.: +33 4 67 33 68 00. Surgical exploration found a fistula at the anterior pil- E-mail address: [email protected] (F. Venail). lar of the round window (Fig. 3); there was no oval-window 1879-7296/$ – see front matter © 2011 Elsevier Masson SAS. All rights reserved. doi:10.1016/j.anorl.2010.12.004 140 M. Al Felasi et al. 125 250 500 1000 2000 4000 8000 125 250 500 1000 2000 4000 8000 0 0 Pre-op AC 20 20 Post-op AC 40 40 60 60 Pre-op AC 80 80 Post-op AC 100 100 Figure 1 Case 1: pre- and post-operative audiometry. Figure 4 Case 2: pre- and post-operative audiometry. The Baseline audiometry (lozenges) found mild high-frequency per- severe pre-operative hearing loss (lozenges) was unchanged by ceptive hearing loss 3 weeks post-trauma. This initial hearing surgery (circles). loss resolved postoperatively (circles). Figure 5 Case 2: peroperative view of round window. Visu- alization of a fistula in the superior part of the round-window Figure 2 Case 1: CT of right temporal bone centered on membrane (arrow). stapes footplate. CT at 3 weeks post-trauma found an aspect of intravestibular depression of the posterior part of the stapes fistula or stapes dislocation, but rather an aspect of foot- footplate (arrow). Note absence of pneumolabyrinth or liquid plate deformity. Following filling using a fascia temporalis effusion in the tympanic cavity. Surgical exploration attributed fragment and fibrin glue, there was rapid improvement, with this abnormality to stapes deformity. resolution of vertigo and normalized audiometry within 1 week (Fig. 1). At 3 months, clinical results were stable, with residual tinnitus. Case 2 A 45-year-old man consulted for left hearing loss, vertigo and tinnitus following violent blowing of the nose. Initial examination had found severe left hearing loss, treated by 1 week’s corticosteroids and vasodilators. The patient con- sulted in our department for persistence of symptoms 2 weeks after the initial trauma. Examination found left per- ceptive hearing loss (Fig. 4) with left vestibular deficit and absence of fistula sign. Surgical exploration found a fistula in the superior part of the round-window membrane (Fig. 5). Despite filling using a fascia temporalis fragment and fibrin glue, the hearing Figure 3 Case 1: peroperative view of round window. loss persisted and vertigo remained unimproved at 1 week Visualization of a perilymphatic fistula at the anterior round- postoperatively. At 3 months, hearing loss and tinnitus were window pillar (arrow). unchanged. Perilymphatic fistula of the round window 141 Discussion a poorer chance of successful outcome. Hearing gener- ally begins to recover 3 to 7 days after direct inner-ear Perilymphatic fistula is easy to diagnose when secondary to trauma, beyond which point any persistence or aggravation tumor extension or temporal bone fracture, but much less constitutes an indication for surgical exploration. Prognosis so in other clinical situations. also seems to depend on early intervention [10], but there So-called ‘‘spontaneous’’ fistula in the round window or would not seem to be any deadline for undertaking surgery: oval window is often associated with a mechanism involving patients operated on more than 6 months post-trauma still sudden pressure change impacting the inner ear,whether via showed reduced but real benefit [5]. the middle ear (nose blowing, sniffing, trauma) or via the cerebrospinal fluid (closed glottis effort, cough, etc.) [2]. Conclusion Ossicular chain or otic capsule abnormalities may promote such fistulae, in 86.3% of cases according to Peter et al. Diagnosis of perilymphatic fistula is difficult. It is primar- [3]. Most such abnormalities concern stapes superstructure, ily founded on history and clinical examination; treatment as in the first of the present cases. Middle ear deformity decision is finally relatively unaffected by complementary (Mondini, Gusher) has also been shown to be a risk factor examinations. Prognosis correlates with interval to surgery for perilymphatic fistula [4]. and baseline hearing loss. Whenever clinically symptomatic The clinical aspect is fairly characteristic: the acute fistula is suspected, surgical exploration of the round and phase associates progressive and sometimes fluctuating oval windows is mandatory. perceptive hearing loss, vertigo and tinnitus. This triad, however, is not very sensitive or specific [5], and in later Conflict of interest statement stages fistula may be suggested only by instability, itera- tive or positional vertigo, mild hearing loss and occasional tinnitus. None. The fistula sign is suggestive, but is reported in only 29 to 71% of cases, depending on the series [6,7]: absence does not References rule out diagnosis, as seen in the present cases. Exploration for fistula sign by pneumatic speculum is difficult, as pres- [1] Telian SA. Surgery for vestibular disorders. In: Cummings CW, sure on the tympano-ossicular system cannot be controlled. et al., editors. Otolaryngology—head and neck surgery. 3rd edn. The test can, however, be made more sensitive and repro- St. Louis: CV Mosby; 1998. p. 2731. ductible by controlling the pressure by a tympanometer [8]. [2] Legent F, Bordure P. Fistules périlymphatiques post- Patients may also not infrequently present with a Tullio phe- traumatiques. Bull Acad Natl Med 1994;178:35—44. [3] Weber PC, Perez BA, Bluestone CD. Congenital perilymphatic nomenon, representing a real ‘‘acoustic fistula sign’’ which fistula and associated middle ear abnormalities. Laryngoscope the clinician needs to identify. 1993;103:160—4. Diagnosis may be supported by imaging, although nor- [4] Elverland HH, Mair WS. Recurrent meningitis, congenital ana- mal imaging is not a disproof. In the acute phase, CT may cusis and Mondini anomaly. Acta Otolaryngol 1983;95:147—51. find pneumolabyrinth, ossicular fracture or dislocation, or [5] Glasscock 3rd ME, Hart MJ, Rosdeutscher JD, et al. Traumatic moderate effusion in the tympanic cavity, which is an indi- perilymphatic fistula: how long can the symptom persist? Am J rect sign of fistula. After the acute phase, CT is no longer Otol 1992;13:333—8. very contributive, at best detecting trauma sequelae or mal- [6] Goto F, Ogawa K, Kunihiro T, et al. Perilymph fistula — 45 case formations liable to promote fistula, as in the first of the analysis. Auris Nasus Larynx 2001;28:29—33. present cases. [7] Vartiainen E, Nuutinen J, Karjalainen S, et al. Perilymph fistula — a diagnostic dilemma. J Laryngol Otol 1991;105:270—3. The sole reliable diagnostic examination is surgical explo- [8] Daspit CP, Churchill D, Linthicum Jr FH. Diagnosis of ration of the windows. Detection can be improved by perilymph fistula using ENG and impedance. Laryngoscope abdominal hyperpressure maneuvers or intrathecal fluores- 1980;90:217—23. cein injection, although this is still little used [9]. [9] Gehrking E, Wisst F, Remmert S, et al. Intraoperative assess- Hearing prognosis correlates tightly with baseline hearing ment of perilymphatic fistulas with intrathecal administration threshold [10], which probably accounts for the difference of fluorescein. Laryngoscope 2002;112:1614—8. in evolution between the present two patients. Exploratory [10] Kubo T, Kohno M, Naramura H, et al. Clinical characteristics surgery is particularly indicated where hearing loss is and hearing recovery in perilymphatic fistulas of different eti- moderate; otherwise, there is a risk of aggravation and ologies. Acta Otolaryngol 1993;113:307—11..
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