Otology & Neurotology 35:582Y588 Ó 2014, Otology & Neurotology, Inc.
Treatment of Traumatic Stapediovestibular Luxation: Case Report With the Introduction of a New Technique and Review of Literature Marie Bogaerts, Je´roˆme Waterval, Joost van Dinther, Thomas Somers, Andrzej Zarowski, and Frans Erwin Offeciers European Institute for Otorhinolaryngology, Wilrijk, Antwerp, Belgium
Objective: Stapediovestibular luxations are rare lesions that are most commonly caused by direct, penetrating trauma to the external ear canal. In this type of ossicular dislocation, disruption of the annular ligament or footplate fracture may lead to a perilymphatic fistula (PLF) presenting with cochleovestibular symptoms including (progressive) sensorineural hearing loss, tinnitus, and vestibular symptoms. The objective of this article is to define the optimal treatment of stapediovestibular luxations and review the literature on this topic. Patient: We present a case of internal stapediovestibular dislocation and pneumolabyrinth after penetrating trauma with predominantly conductive hearing loss and incapacitating vertigo. Intervention: Middle ear inspection with removal of the luxated incus, repositioning of the stapes with a ‘‘stapedial strut’’ and closure of the tympanic membrane.
Main outcome measures: Hearing outcome and vestibular symptoms of this patient are presented, and all comparable cases in the literature are reviewed. Results: Complete resolution of the vestibular symptoms and stabilization of the bone conduction thresholds. Conclusion: In patients with pneumolabyrinth after middle ear trauma with mild symptoms, we recommend initial conservative treatment with close monitoring of hearing. In patients with severe, persisting, or progressive vestibulocochlear symptoms, exploratory tympanotomy should be performed to check for and treat PLF. Oval window fistula repair is reported to have variable hearing outcomes but offers complete resolution of vestibular symptoms in most cases. The stapedial strut is one of the possible surgical techniques in case of an internally luxated stapes. Key Words: Operative techniqueVOssicular traumaV Perilymphatic fistulaVStapes luxation. Otol Neurotol 35:582Y588, 2014.
Stapediovestibular dislocation is usually caused by penetrating trauma through the external ear canal or sometimes by indirect trauma. The majority of the literature reports is Japanese because apparently the Japanese are fanatic ear pick users (1). This is an uncommon finding because the stapes is protected from direct trauma by the overhanging scutum. The stapes can be depressed internally into the vestibule (internal dislocation), or it can be dislocated into the tympanic cavity (external dislocation). A comminuted fracture of the footplate may also cause stapediovestibular dislocation. In the largest radiologic collection of ossicular injuries (166 patients), only five
had stapediovestibular dislocation, three of which had an internal dislocation (2). We present a case of internal stapediovestibular dislocation and introduce a new surgical technique. The literature on traumatic stapediovestibular dislocations is reviewed. CASE REPORT A 32-year-old woman was referred to our tertiary otologic clinic a week after penetrating trauma to her left ear canal. Her child had accidentally perforated her ear drum with the pin of a head massage device (Fig. 1A). She immediately reported otalgia, bleeding, hearing loss, and tinnitus. A few days afterward, the patient developed vertigo worsening upon head movements. Otoscopy revealed a large anterior tympanic membrane perforation. Neither the ossicular chain nor the round window niche was visible. No spontaneous nystagmus was observed. Strongly suspecting a perilymphatic fistula (PLF), we did
Address correspondence and reprint requests to Marie Bogaerts, M.D., European Institute for Otorhinolaryngology, Oosterveldlaan 24, 2610 Wilrijk, Antwerp, Belgium Presented at the Flemish-Dutch Otologic Society. Marie Bogaerts and Je´roˆme Waterval shared first authorship. The authors declare no conflicts of interest.
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FIG. 1. Preoperative situation. A, Head massage device. B, Preoperative audiogram (left). C and D, (different magnification) Cone beam images (double oblique reconstructions in the plane of the stapes) of the left temporal bone displaying the depressed stapes and air in the vestibule directly medial and posterior to the stapes (asterisks). Anterior tympanic membrane perforation (arrow ).
not search for a positive fistula test to avoid additional inner ear damage. Audiometry revealed predominantly conductive hearing loss on the left side (Fig. 1B) with pure tone average of 38 dB HL and air-bone gap of 20 dB HL. Worst bone conduction thresholds were 25 dB HL at 1 and 2 kHz (identical to the audiogram immediately after the accident). Vestibular evoked myogenic potentials on the left side using bone conduction tone bursts were found at 130 dB SPL. We did not perform nystagmography. Cone beam CT was performed (0.1 mm). Luxation of the incudomallear joint was observed as well as depression of the stapes into the vestibule (Fig. 1, C and D). A limited amount of air was present within the labyrinth confined to the area of the vestibule. High-dose intravenous corticosteroids and antibiotics (cefuroxim) were administered. Because of persisting vertigo 9 days after trauma, we decided to perform a middle ear inspection to close the PLF and decrease the
risk of labyrinthitis facilitated by the open middle ear. Upon opening the middle ear, abnormal mobility of both malleus and incus were noticed. No ossicular fractures were seen. The hypermobile incus was removed and placed under the periostal flap for reconstruction purposes in second stage surgery. No perilymph leakage was seen, possibly explained by hypotensive anesthesia. The stapes was found to be hypermobile and depressed into the vestibule, especially the posterior crus. After gentle retraction, the stapes sank back into the vestibule. A funnel-shaped silastic was placed between the crura as a bar over the promontory to support the stapes and prevent it from sinking into the vestibule again (Fig. 2CYD). Fibrin glue was applied on the oval window for sealing and fixation purposes. The tympanic membrane perforation was closed with fascia in underlay. Postoperatively, the vertigo and tinnitus disappeared and bone conduction thresholds were stable (Fig. 3A). Two months postoperatively, a repeat cone-beam CT Otology & Neurotology, Vol. 35, No. 4, 2014
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FIG. 2. Intraoperative stills. A, Large anterior tympanic membrane perforation (after elevation of the canal skin). B, Palpation of the hypermobile incus, which is then removed. Note the fibrous tissue between the chorda tympani and the incus. C, Posteriorly depressed stapes with curved stapedial muscle (dashed line, the distance between the pyramidal process and the neck of the stapes is decreased). D, Silastic sheet is introduced into the middle ear. E, Placement of silastic between the crura after elevation of the stapes (note the straight course of the stapedial muscle again). F, Final position of the silastic preventing the stapes from depressing again.
FIG. 3. Postoperative situation and silatic strut principle. A, Postoperative audiogram. B, Double oblique cone beam images 2 months postoperatively displaying resorption of the air in the vestibule and normal orientation of the stapes and the foot plate and showing the silastic (dashed line in inserted illustration). C, The silastic strut principle. FN = facial nerve. The silastic is used as a strut to lift the depressed stapes. Otology & Neurotology, Vol. 35, No. 4, 2014
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STAPEDIOVESTIBULAR LUXATION showed the stapes footplate positioned at the level of the oval window and resolution of pneumolabyrinth (Fig. 3B).
DISCUSSION We performed a literature search on traumatic stapediovestibular luxation. We found 18 surgically treated cases (Table 1). Thirteen of the 18 reported stapediovestibular dislocations were caused by penetrating trauma. The other cases were caused by blunt head trauma (3Y6) or barotrauma (7). Our case, as well as the cases we found in the literature, presented with vestibulocochlear symptoms, raising the suspicion of PLF. Vestibulocochlear symptoms include (progressive) sensorineural hearing loss, tinnitus, vertigo, and nystagmus. PLF is an abnormal communication between the inner ear and middle ear or mastoid secondary to a bony defect in the otic capsule, almost always the oval or round window. In case of a stapediovestibular dislocation, PLF is the result of a disrupted annular ligament or a fractured footplate. An important (radiologic) sign of PLF is pneumolabyrinth, the presence of air in the labyrinth. Less frequently, an opacity on CT suspect for perilymph fluid can be seen in the mesotympanum or more specifically in the round window niche. There is discussion whether in every case of traumatic pneumolabyrinth (radiologic diagnosis) middle ear exploration is indicated. With the widespread availability of high-resolution CT, pneumolabyrinth after middle ear or temporal bone trauma is observed more frequently. However, the presence of pneumolabyrinth is not a proof of active leakage as the leak could have sealed spontaneously, leaving unresorbed air within the labyrinth. Some authors described (8,9) conservative treatment in 3 cases of radiologically confirmed stapedial luxation and/or pneumolabyrinth after penetrating trauma to the external ear canal (Table 2), leading to resolution of vestibular symptoms and improved hearing. Stable hearing levels and absence or improvement of vestibular symptoms justify conservative treatment with close monitoring of the hearing (10,11). It is generally accepted that in case of a (suspected) persistent PLF surgical exploration is indicated to detect and close the fistula. If leakage at the level of the round window is found, sealing is straight-forward. However, controversy exists on what to do with a displaced stapes in combination with perilymph leakage at the level of the oval window. The decision for the type of surgical repair is based on different factors: the condition and position of the stapes as well as preoperative residual hearing. Sarac proposed that, if the stapes is only slightly depressed into the vestibule, reconstruction with or without removal of the stapes may lead to fairly good postoperative hearing results (5). However, if the stapes is deeply depressed into the vestibule, the risk of causing additional inner ear damage by lifting it out increases. On the other hand, leaving a deeply depressed stapes in place may cause late inner ear damage due to scarring around the stapes in
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the vestibule. Fourteen of 18 reports are internal stapediovestibular dislocations treated in various surgical ways. In 1 case, surgical labyrinthectomy was performed because of incapacitating vertigo without serviceable hearing (12). The stapes was left in the vestibule in 2 cases (13,14), elevated into the oval window in 2 cases besides ours (5,15) and removed (stapedectomy) in 9 cases (1,6,9,16Y21). Hearing outcome was variable (Table 1), but vestibular symptoms resolved in all cases after fistula repair. In 6 cases, hearing thresholds deteriorated during conservative treatment (12Y17). In only one of them, bone conduction thresholds improved after surgical intervention (13). Our patient presented with almost pure conductive hearing loss and an air-bone gap that was smaller than we would have expected in case of a dislocated ossicular chain. A possible explanation is the hypermobility of the stapes. It seems likely that a loose footplate will vibrate more easily with vibration of the surrounding structures (i.e., tympanic membrane and ossicles). We administered antibiotics to minimize the risk of labyrinthitis, although there is little evidence on this topic. The persisting vertigo prompted us to perform surgery. The purpose was closing the suspected perilymphatic fistula and preserve inner ear function. Because the stapes was intact and also in order to minimize the risk of inner ear damage, we decided not to perform stapedectomy. Instead, the stapes was carefully lifted out of the vestibule into the oval window and stabilized with a ‘‘silastic strut’’ between the crura and on the promontory, holding the stapes at the level of the oval window (Fig. 3C). IfVduring second stage surgeryVthe stapes would appear to be fixated, (laser) stapedotomy with placement of a malleovestibular piston could be performed, of course only if the malleus would have regained its normal mobility again. To avoid pressure on the stapes, no ossicular reconstruction was performed. Despite manipulation of the deeply depressed stapes, bone-conduction thresholds remained stable in the postoperative period (6 months). The postoperative air-bone gap again was smaller than we expected. This could be explained by the presence of fibrous tissue between the tympanic membrane, malleus and stapes, or again by hypermobility of the stapes. CONCLUSION Vestibulocochlear symptoms after temporal bone trauma should raise the suspicion of PLF. Pneumolabyrinth or temporal bone fracture should be ruled out by highresolution CT scan. There is no established protocol for the management of posttraumatic pneumolabyrinth. In patients with mild symptoms and isolated pneumolabyrinth, we recommend initial conservative treatment with close monitoring of the hearing. In patients with severe, persisting or progressive vestibulocochlear symptoms explorative tympanotomy should be performed to check for and treat PLF, even without radiological evidence, to prevent progression of sensorineural hearing loss and vestibular function loss (4,15,18). Management of stapediovestibular dislocation is influenced by the condition and Otology & Neurotology, Vol. 35, No. 4, 2014
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External dislocation/miscellaneous
Stapedectomy
Stapes elevated into OW
Stapes left in vestibule
Author
Cause
Hatano et al. (13)
Penetrating trauma with earpick
Snelling et al. (14)
Penetrating trauma with hair grip
Tsubota et al. (15)
Penetrating trauma with earpick
Sarac et al. (5) Our case
Head trauma (fall on the occiput) Sharp trauma into ear canal
Kobayashi and Gyo (1)
Penetrating trauma with earpick
Chujo et al. (6)
Blow to opposite side of the head
Hidaka et al. (9)
Stapedial luxation treated operatively Otoscopy/CT findings*
Preoperative hearing
Interval intervention
TM perforation, pneumolabyrinth, deeply depressed stapes TM perforation, pneumolabyrinth, incudal dislocation and depressed stapes TM perforation, pneumolabyrinth, incudal dislocation and depressed stapes Normal, pneumolabyrinth TM perforation, pneumolabyrinth, depressed stapes, incudal dislocation Protrusion of long process incus through TM, no CT Normal, normal
Mild mixed HL PTA 40 dB, sudden evolution to severe mixed HL after 2 d (BC 45 dB)
11 d
Moderate mixed HL PTA 60 dB (BC 13 dB), evolved to PTA severe mixed HL 87 (BC appr. 60 dB) after 3 mo Severe mixed HL PTA 78 dB (BC 50 dB), evolution to PTA 104 dB after 5 d (BC not measurable) during conservative treatment Profound SNHL
3 wk
Mixed hearing loss PTA 38 dB (BC appr 20 dB)
9d
Moderate mixed HL PTA 58 dB (BC 25 dB)
2 wk
Maximal CHL
2 mo
Penetrating trauma with chopstick
TM perforation, pneumolabyrinth
Near-total deafness PTA 100 dB
Nishiike et al. (16)
Penetrating trauma
TM perforation, pneumolabyrinth, depressed stapes
Moderate mixed HL PTA 58 dB (BC 25 dB), evolution to PTA 77 dB (BC 25 dB) after 4 d
Vanderstock et al. (17)
Penetrating trauma with knitting needle
TM perforation, no CT
Yamasoba et al. (19)
Penetrating trauma with earpick
Yanagihara and Nishioka (18)
Penetrating trauma with earpick
TM perforation, pneumolabyrinth, depressed stapes TM perforation
Mixed HL PTA 55 dB (BC 18 dB) evolved to PTA 80 (BC 33 dB) after 3 d PTA 30 dB mixed or SNHL, BC not specified
Ishida et al. (20)
Penetrating trauma with tip of a comb
Ederies et al. (21)
Penetrating trauma with eyeglasses
Kagoya et al. (3)
Traffic accident
Intact TM, external stapedial dislocation, longitudinal temporal bone fracture
Maximal CHL PTA 60 dB (BC 10 dB)
Kim et al. (4)
Blunt injury to temporal bone with baseball Penetrating trauma with toothpick Barotrauma
Normal, soft tissue density in OW region TM perforation, no CT TM perforation, no CT TM perforation, depressed stapes
Mixed HL PTA 20 dB (BC 15 dB), high-frequency sloping
1d
CHL PTA 46 dB (BC 11 dB)
1d
Kim et al. (4) Whinney et al. (7) Herman et al. (12)
Penetrating trauma with cotton tip
Intact TM, ossicular chain dislocation, pneumolabyrinth TM perforation, pneumolabyrinth, anteriorly rotated depressed stapes
Moderate SNHL 40 dB (mild conductive component, after surgical closure of TM perforation) Severe mixed HL PTA 86 dB (BC 40 dB) Mixed HL PTA 88 dB (BC 39 dB)
Severe SNHL PTA 90 dB Initially moderate mixed HL, evolved to deafness
5d
4d
32 d (late increase vestibular symptoms) 4d
2 wk 0 d (severe vestibular symptoms) 4 mo
8d 2 mo (late increase vestibular symptoms)
16 mo
11 d (also steroid therapy) 3 yr (late increase vestibular symptoms)
TM indicates tympanic membrane; SNHL, sensorineural hearing loss; CHL, conductive hearing loss; PTA, pure tone average (in dB Hearing Level at 0.5, 1.0, and 2.0 KHz); HL, hearing loss; BC, bone conduction; OW, oval window; RW, round window; perich, perichondrium.
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Perilymph leakage
Sealed
Yes
Yes
Stapes deeply depressed and invisible (CT diagnosis)
None, cartilaginous columella between sealed oval window and TM
Moderate mixed hearing loss PTA 51 dB (BC 15 dB)
+
Yes
Fat
Intact, depressed, incuidal luxation
None
Deafness
-
Intact, slightly depressed
Withdrawn from vestibule into OW, cartilage columella
PTA 90 dB (BC not measurable)
=
Withdrawn from vestibule into OW Withdrawn from vestibule into OW, silastic strut between crura
Profound SNHL
=
Mixed hearing loss PTA 28 dB (BC appr 20 dB)
=
Stapedectomy, malleovestibulopexy
Mixed HL PTA 30 dB (BC 25 dB)
=
Stapedectomy, TeflonA piston on intact incus
Mild CHL PTA 25 dB
=
Stapedectomy, oval window gentamicin injection
Deaf
=
Withdrawn from vestibule, same stage modified incus interposition
Severe mixed HL evolution to PTA 77 dB (BC 38 dB)
-
Stapedectomy, TeflonA piston on intact incus
Moderate SNHL PTA 45 dB
-
Removal stapes, cartilaginous columella between sealed oval window and TM Withdrawn from vestibule, incus replaced in original position
Mixed HL 45 dB, BC not specified
Yes (OW+RW)
Fascia + fibrin glue
Stapes situation
Yes
Fat
Intact, depressed
No
Fibrin glue
Intact, depressed
No
Fascia
Yes
Yes
?
Yes
Yes
Fascia
No
Vein
Yes
Perich
Intact, deeply depressed, incuidal dislocation
Yes (OW+ RW)
Perich
Mildly anteriorly tilted, leakage adjacent to anterior crus
Yes
Connective tissue
No
Fat + perich
No
No
Yes
Fascia (OW+RW)
Yes No
Fascia (OW+RW) Fat
?
Fat
Stapes dislocation, footplate fracture and anterior crus fracture Intact, posterior dislocation, hypermobile, also after reposition, incudostapedial dislocation Intact, fully depressed, incudostapedial dislocation Depressed stapes, incudostapedial and incudomallear dislocation Deeply depressed into vestibule
Fractured crura, depressed footplate, incudostapedial dislocation Footplate fracture, depressed stapes, anterior rotation, fracture suprastructure, incudostapedial dislocation Incudostapedial dislocation, outward and downward stapedial dislocation, footplate fractured and partially disappeared Avulsed
(Stapes) intervention
BC threshold outcome
=/- (?)
PTA stable
=
Mild mixed HL PTA 25 dB (BC 13 dB)
+
PTA stable
=
PTA 23 dB (BC 10 dB)
=
?
Slightly improved mixed HL
=
?
Deaf
-
Removal of stapes, connective tissue between sealed OW and incus Removal loose posterior crus, anterior part fixed to medial wall of vestibule Cartilage columella between oval window and incus
Avulsed
Postoperative hearing
Fracture of the footplate
None
SNHL PTA 25 dB
+
Intact, depressed
Labyrinthectomy
Deaf
=
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M. BOGAERTS ET AL. TABLE 2.
Author
Cause
Stapedial luxation treated conservatively
Otoscopy/CT findings*
Hearing after trauma
Hearing at follow-up
Vestibular symptoms
Lao and Niparko (8) Penetrating trauma TM perforation, intact Moderate to profound Mild CHL PTA 30 dB Intermittent unsteadiness, with tree branch incudostapedial joint, mixed HL PTA 71 dB (BC 11 dB) resolved after 6 d pneumolabyrinth, (BC 35) stapedial luxation Hidaka et al. (9) Penetrating trauma TM perforation, Mixed HL PTA 36 dB PTA 18 dB (BC 13 dB) Vertigo subsided after 5 d with ear pick pneumolabyrinth (BC 10 dB) Hidaka et al. (9) Penetrating trauma TM perforation, Mixed HL PTA 76 dB PTA 35 dB (BC 15 dB) Vertigo subsided after 7 d with ear pick pneumolabyrinth (BC 11 dB) TM indicates tympanic membrane; CHL, conductive hearing loss; PTA, pure tone average (in dB Hearing Level at 0.5, 1.0, and 2.0 KHz); HL, hearing loss; BC, bone conduction.
position of the stapes, as well as the preoperative hearing thresholds. We describe a new technique lifting an intact and depressed stapes out of the vestibule, supporting it by means of a (silastic) strut. REFERENCES 1. Kobayashi T, Gyo K. Earpick injury of the stapes. Am J Otolaryngol 2000;21:340Y3. 2. Meriot P, Veillon F, Garcia JF, et al. CT appearances of ossicular injuries. Radiographics 1997;17:1445Y54. 3. Kagoya R, Ito K, Kashio A, Karino S, Yamasoba T. Dislocation of stapes with footplate fracture caused by indirect trauma. Ann Otol Rhinol Laryngol 2010;119:628Y30. 4. Kim SH, Kazahaya K, Handler SD. Traumatic perilymphatic fistulas in children: etiology, diagnosis and management. Int J Pediatr Otorhinolaryngol 2001;60:147Y53. 5. Sarac S, Cengel S, Sennaroglu L. Pneumolabyrinth following traumatic luxation of the stapes into the vestibule. Int J Pediatr Otorhinolaryngol 2006;70:159Y61. 6. Chujo K, Nakagawa T, Komune S. Temporal bone fracture with ossicular dislocation caused by a blow to the opposite side of the head. Auris Nasus Larynx 2008;35:273Y5. 7. Whinney DJ, Parikh AA, Brookes GB. Barotraumatic fracture of the stapes footplate. Am J Otol 1996;17:697Y9. 8. Lao WW, Niparko JK. Assessment of changes in cochlear function with pneumolabyrinth after middle ear trauma. Otol Neurotol 2007;28:1013Y7. 9. Hidaka H, Miyazaki M, Kawase T, Kobayashi T. Traumatic pneumolabyrinth: air location and hearing outcome. Otol Neurotol 2012;33:123Y31.
10. Gunesh RP, Huber AM. Traumatic perilymphatic fistula. Ann Otol Rhinol Laryngol 2003;112:221Y2. 11. Prisman E, Ramsden JD, Blaser S, Papsin B. Traumatic perilymphatic fistula with pneumolabyrinth: diagnosis and management. Laryngoscope 2011;121:856Y9. 12. Herman P, Guichard JP, Van den Abbeele T, et al. Traumatic luxation of the stapes evidenced by high-resolution CT. AJNR Am J Neuroradiol 1996;17:1242Y4. 13. Hatano A, Rikitake M, Komori M, Irie T, Moriyama H. Traumatic perilymphatic fistula with the luxation of the stapes into the vestibule. Auris Nasus Larynx 2009;36:474Y8. 14. Snelling JD, Bennett A, Wilson P, Wickstead M. Unusual middleear mischief: trans-tympanic trauma from a hair grip resulting in ossicular, facial nerve and oval window disruption. J Laryngol Otol. 2006;120:793Y5. 15. Tsubota M, Shojaku H, Watanabe Y. Prognosis of inner ear function in pneumolabyrinth: case report and literature review. Am J Otolaryngol 2009;30:423Y6. 16. Nishiike S, Hyo Y, Fukushima H. Stapediovestibular dislocation with pneumolabyrinth. J Laryngol Otol 2008;122:419Y21. 17. Vanderstock L, Vermeersch H, De Vel E. Traumatic luxation of the stapes. J Laryngol Otol 1983;97:533Y7. 18. Yanagihara N, Nishioka I. Pneumolabyrinth in perilymphatic fistula: report of three cases. Am J Otol 1987;8:313Y8. 19. Yamasoba T, Amagai N, Karino S. Traumatic luxation of the stapes into the vestibule. Otolaryngol Head Neck Surg 2003;129: 287Y90. 20. Ishida K, Sakai M, Hiroi M, Sekine M, Takeo T. Traumatic fracture of the stapes and perilymph fistula: report of a case. Tokai J Exp Clin Med 2006;31:133Y5. 21. Ederies A, Yuen HW, Chen JM, Aviv RI, Symons SP. Traumatic stapes fracture with rotation and subluxation into the vestibule and pneumolabyrinth. Laryngoscope 2009;119:1195Y7.
Otology & Neurotology, Vol. 35, No. 4, 2014
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Treatment of Traumatic Stapediovestibular Luxation: Case Report With the Introduction of a New Technique and Review of Literature Marie Bogaerts, Je´roˆme Waterval, Joost van Dinther, Thomas Somers, Andrzej Zarowski, and Frans Erwin Offeciers European Institute for Otorhinolaryngology, Wilrijk, Antwerp, Belgium
Objective: Stapediovestibular luxations are rare lesions that are most commonly caused by direct, penetrating trauma to the external ear canal. In this type of ossicular dislocation, disruption of the annular ligament or footplate fracture may lead to a perilymphatic fistula (PLF) presenting with cochleovestibular symptoms including (progressive) sensorineural hearing loss, tinnitus, and vestibular symptoms. The objective of this article is to define the optimal treatment of stapediovestibular luxations and review the literature on this topic. Patient: We present a case of internal stapediovestibular dislocation and pneumolabyrinth after penetrating trauma with predominantly conductive hearing loss and incapacitating vertigo. Intervention: Middle ear inspection with removal of the luxated incus, repositioning of the stapes with a ‘‘stapedial strut’’ and closure of the tympanic membrane.
Main outcome measures: Hearing outcome and vestibular symptoms of this patient are presented, and all comparable cases in the literature are reviewed. Results: Complete resolution of the vestibular symptoms and stabilization of the bone conduction thresholds. Conclusion: In patients with pneumolabyrinth after middle ear trauma with mild symptoms, we recommend initial conservative treatment with close monitoring of hearing. In patients with severe, persisting, or progressive vestibulocochlear symptoms, exploratory tympanotomy should be performed to check for and treat PLF. Oval window fistula repair is reported to have variable hearing outcomes but offers complete resolution of vestibular symptoms in most cases. The stapedial strut is one of the possible surgical techniques in case of an internally luxated stapes. Key Words: Operative techniqueVOssicular traumaV Perilymphatic fistulaVStapes luxation. Otol Neurotol 35:582Y588, 2014.
Stapediovestibular dislocation is usually caused by penetrating trauma through the external ear canal or sometimes by indirect trauma. The majority of the literature reports is Japanese because apparently the Japanese are fanatic ear pick users (1). This is an uncommon finding because the stapes is protected from direct trauma by the overhanging scutum. The stapes can be depressed internally into the vestibule (internal dislocation), or it can be dislocated into the tympanic cavity (external dislocation). A comminuted fracture of the footplate may also cause stapediovestibular dislocation. In the largest radiologic collection of ossicular injuries (166 patients), only five
had stapediovestibular dislocation, three of which had an internal dislocation (2). We present a case of internal stapediovestibular dislocation and introduce a new surgical technique. The literature on traumatic stapediovestibular dislocations is reviewed. CASE REPORT A 32-year-old woman was referred to our tertiary otologic clinic a week after penetrating trauma to her left ear canal. Her child had accidentally perforated her ear drum with the pin of a head massage device (Fig. 1A). She immediately reported otalgia, bleeding, hearing loss, and tinnitus. A few days afterward, the patient developed vertigo worsening upon head movements. Otoscopy revealed a large anterior tympanic membrane perforation. Neither the ossicular chain nor the round window niche was visible. No spontaneous nystagmus was observed. Strongly suspecting a perilymphatic fistula (PLF), we did
Address correspondence and reprint requests to Marie Bogaerts, M.D., European Institute for Otorhinolaryngology, Oosterveldlaan 24, 2610 Wilrijk, Antwerp, Belgium Presented at the Flemish-Dutch Otologic Society. Marie Bogaerts and Je´roˆme Waterval shared first authorship. The authors declare no conflicts of interest.
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FIG. 1. Preoperative situation. A, Head massage device. B, Preoperative audiogram (left). C and D, (different magnification) Cone beam images (double oblique reconstructions in the plane of the stapes) of the left temporal bone displaying the depressed stapes and air in the vestibule directly medial and posterior to the stapes (asterisks). Anterior tympanic membrane perforation (arrow ).
not search for a positive fistula test to avoid additional inner ear damage. Audiometry revealed predominantly conductive hearing loss on the left side (Fig. 1B) with pure tone average of 38 dB HL and air-bone gap of 20 dB HL. Worst bone conduction thresholds were 25 dB HL at 1 and 2 kHz (identical to the audiogram immediately after the accident). Vestibular evoked myogenic potentials on the left side using bone conduction tone bursts were found at 130 dB SPL. We did not perform nystagmography. Cone beam CT was performed (0.1 mm). Luxation of the incudomallear joint was observed as well as depression of the stapes into the vestibule (Fig. 1, C and D). A limited amount of air was present within the labyrinth confined to the area of the vestibule. High-dose intravenous corticosteroids and antibiotics (cefuroxim) were administered. Because of persisting vertigo 9 days after trauma, we decided to perform a middle ear inspection to close the PLF and decrease the
risk of labyrinthitis facilitated by the open middle ear. Upon opening the middle ear, abnormal mobility of both malleus and incus were noticed. No ossicular fractures were seen. The hypermobile incus was removed and placed under the periostal flap for reconstruction purposes in second stage surgery. No perilymph leakage was seen, possibly explained by hypotensive anesthesia. The stapes was found to be hypermobile and depressed into the vestibule, especially the posterior crus. After gentle retraction, the stapes sank back into the vestibule. A funnel-shaped silastic was placed between the crura as a bar over the promontory to support the stapes and prevent it from sinking into the vestibule again (Fig. 2CYD). Fibrin glue was applied on the oval window for sealing and fixation purposes. The tympanic membrane perforation was closed with fascia in underlay. Postoperatively, the vertigo and tinnitus disappeared and bone conduction thresholds were stable (Fig. 3A). Two months postoperatively, a repeat cone-beam CT Otology & Neurotology, Vol. 35, No. 4, 2014
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M. BOGAERTS ET AL.
FIG. 2. Intraoperative stills. A, Large anterior tympanic membrane perforation (after elevation of the canal skin). B, Palpation of the hypermobile incus, which is then removed. Note the fibrous tissue between the chorda tympani and the incus. C, Posteriorly depressed stapes with curved stapedial muscle (dashed line, the distance between the pyramidal process and the neck of the stapes is decreased). D, Silastic sheet is introduced into the middle ear. E, Placement of silastic between the crura after elevation of the stapes (note the straight course of the stapedial muscle again). F, Final position of the silastic preventing the stapes from depressing again.
FIG. 3. Postoperative situation and silatic strut principle. A, Postoperative audiogram. B, Double oblique cone beam images 2 months postoperatively displaying resorption of the air in the vestibule and normal orientation of the stapes and the foot plate and showing the silastic (dashed line in inserted illustration). C, The silastic strut principle. FN = facial nerve. The silastic is used as a strut to lift the depressed stapes. Otology & Neurotology, Vol. 35, No. 4, 2014
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STAPEDIOVESTIBULAR LUXATION showed the stapes footplate positioned at the level of the oval window and resolution of pneumolabyrinth (Fig. 3B).
DISCUSSION We performed a literature search on traumatic stapediovestibular luxation. We found 18 surgically treated cases (Table 1). Thirteen of the 18 reported stapediovestibular dislocations were caused by penetrating trauma. The other cases were caused by blunt head trauma (3Y6) or barotrauma (7). Our case, as well as the cases we found in the literature, presented with vestibulocochlear symptoms, raising the suspicion of PLF. Vestibulocochlear symptoms include (progressive) sensorineural hearing loss, tinnitus, vertigo, and nystagmus. PLF is an abnormal communication between the inner ear and middle ear or mastoid secondary to a bony defect in the otic capsule, almost always the oval or round window. In case of a stapediovestibular dislocation, PLF is the result of a disrupted annular ligament or a fractured footplate. An important (radiologic) sign of PLF is pneumolabyrinth, the presence of air in the labyrinth. Less frequently, an opacity on CT suspect for perilymph fluid can be seen in the mesotympanum or more specifically in the round window niche. There is discussion whether in every case of traumatic pneumolabyrinth (radiologic diagnosis) middle ear exploration is indicated. With the widespread availability of high-resolution CT, pneumolabyrinth after middle ear or temporal bone trauma is observed more frequently. However, the presence of pneumolabyrinth is not a proof of active leakage as the leak could have sealed spontaneously, leaving unresorbed air within the labyrinth. Some authors described (8,9) conservative treatment in 3 cases of radiologically confirmed stapedial luxation and/or pneumolabyrinth after penetrating trauma to the external ear canal (Table 2), leading to resolution of vestibular symptoms and improved hearing. Stable hearing levels and absence or improvement of vestibular symptoms justify conservative treatment with close monitoring of the hearing (10,11). It is generally accepted that in case of a (suspected) persistent PLF surgical exploration is indicated to detect and close the fistula. If leakage at the level of the round window is found, sealing is straight-forward. However, controversy exists on what to do with a displaced stapes in combination with perilymph leakage at the level of the oval window. The decision for the type of surgical repair is based on different factors: the condition and position of the stapes as well as preoperative residual hearing. Sarac proposed that, if the stapes is only slightly depressed into the vestibule, reconstruction with or without removal of the stapes may lead to fairly good postoperative hearing results (5). However, if the stapes is deeply depressed into the vestibule, the risk of causing additional inner ear damage by lifting it out increases. On the other hand, leaving a deeply depressed stapes in place may cause late inner ear damage due to scarring around the stapes in
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the vestibule. Fourteen of 18 reports are internal stapediovestibular dislocations treated in various surgical ways. In 1 case, surgical labyrinthectomy was performed because of incapacitating vertigo without serviceable hearing (12). The stapes was left in the vestibule in 2 cases (13,14), elevated into the oval window in 2 cases besides ours (5,15) and removed (stapedectomy) in 9 cases (1,6,9,16Y21). Hearing outcome was variable (Table 1), but vestibular symptoms resolved in all cases after fistula repair. In 6 cases, hearing thresholds deteriorated during conservative treatment (12Y17). In only one of them, bone conduction thresholds improved after surgical intervention (13). Our patient presented with almost pure conductive hearing loss and an air-bone gap that was smaller than we would have expected in case of a dislocated ossicular chain. A possible explanation is the hypermobility of the stapes. It seems likely that a loose footplate will vibrate more easily with vibration of the surrounding structures (i.e., tympanic membrane and ossicles). We administered antibiotics to minimize the risk of labyrinthitis, although there is little evidence on this topic. The persisting vertigo prompted us to perform surgery. The purpose was closing the suspected perilymphatic fistula and preserve inner ear function. Because the stapes was intact and also in order to minimize the risk of inner ear damage, we decided not to perform stapedectomy. Instead, the stapes was carefully lifted out of the vestibule into the oval window and stabilized with a ‘‘silastic strut’’ between the crura and on the promontory, holding the stapes at the level of the oval window (Fig. 3C). IfVduring second stage surgeryVthe stapes would appear to be fixated, (laser) stapedotomy with placement of a malleovestibular piston could be performed, of course only if the malleus would have regained its normal mobility again. To avoid pressure on the stapes, no ossicular reconstruction was performed. Despite manipulation of the deeply depressed stapes, bone-conduction thresholds remained stable in the postoperative period (6 months). The postoperative air-bone gap again was smaller than we expected. This could be explained by the presence of fibrous tissue between the tympanic membrane, malleus and stapes, or again by hypermobility of the stapes. CONCLUSION Vestibulocochlear symptoms after temporal bone trauma should raise the suspicion of PLF. Pneumolabyrinth or temporal bone fracture should be ruled out by highresolution CT scan. There is no established protocol for the management of posttraumatic pneumolabyrinth. In patients with mild symptoms and isolated pneumolabyrinth, we recommend initial conservative treatment with close monitoring of the hearing. In patients with severe, persisting or progressive vestibulocochlear symptoms explorative tympanotomy should be performed to check for and treat PLF, even without radiological evidence, to prevent progression of sensorineural hearing loss and vestibular function loss (4,15,18). Management of stapediovestibular dislocation is influenced by the condition and Otology & Neurotology, Vol. 35, No. 4, 2014
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M. BOGAERTS ET AL. TABLE 1.
External dislocation/miscellaneous
Stapedectomy
Stapes elevated into OW
Stapes left in vestibule
Author
Cause
Hatano et al. (13)
Penetrating trauma with earpick
Snelling et al. (14)
Penetrating trauma with hair grip
Tsubota et al. (15)
Penetrating trauma with earpick
Sarac et al. (5) Our case
Head trauma (fall on the occiput) Sharp trauma into ear canal
Kobayashi and Gyo (1)
Penetrating trauma with earpick
Chujo et al. (6)
Blow to opposite side of the head
Hidaka et al. (9)
Stapedial luxation treated operatively Otoscopy/CT findings*
Preoperative hearing
Interval intervention
TM perforation, pneumolabyrinth, deeply depressed stapes TM perforation, pneumolabyrinth, incudal dislocation and depressed stapes TM perforation, pneumolabyrinth, incudal dislocation and depressed stapes Normal, pneumolabyrinth TM perforation, pneumolabyrinth, depressed stapes, incudal dislocation Protrusion of long process incus through TM, no CT Normal, normal
Mild mixed HL PTA 40 dB, sudden evolution to severe mixed HL after 2 d (BC 45 dB)
11 d
Moderate mixed HL PTA 60 dB (BC 13 dB), evolved to PTA severe mixed HL 87 (BC appr. 60 dB) after 3 mo Severe mixed HL PTA 78 dB (BC 50 dB), evolution to PTA 104 dB after 5 d (BC not measurable) during conservative treatment Profound SNHL
3 wk
Mixed hearing loss PTA 38 dB (BC appr 20 dB)
9d
Moderate mixed HL PTA 58 dB (BC 25 dB)
2 wk
Maximal CHL
2 mo
Penetrating trauma with chopstick
TM perforation, pneumolabyrinth
Near-total deafness PTA 100 dB
Nishiike et al. (16)
Penetrating trauma
TM perforation, pneumolabyrinth, depressed stapes
Moderate mixed HL PTA 58 dB (BC 25 dB), evolution to PTA 77 dB (BC 25 dB) after 4 d
Vanderstock et al. (17)
Penetrating trauma with knitting needle
TM perforation, no CT
Yamasoba et al. (19)
Penetrating trauma with earpick
Yanagihara and Nishioka (18)
Penetrating trauma with earpick
TM perforation, pneumolabyrinth, depressed stapes TM perforation
Mixed HL PTA 55 dB (BC 18 dB) evolved to PTA 80 (BC 33 dB) after 3 d PTA 30 dB mixed or SNHL, BC not specified
Ishida et al. (20)
Penetrating trauma with tip of a comb
Ederies et al. (21)
Penetrating trauma with eyeglasses
Kagoya et al. (3)
Traffic accident
Intact TM, external stapedial dislocation, longitudinal temporal bone fracture
Maximal CHL PTA 60 dB (BC 10 dB)
Kim et al. (4)
Blunt injury to temporal bone with baseball Penetrating trauma with toothpick Barotrauma
Normal, soft tissue density in OW region TM perforation, no CT TM perforation, no CT TM perforation, depressed stapes
Mixed HL PTA 20 dB (BC 15 dB), high-frequency sloping
1d
CHL PTA 46 dB (BC 11 dB)
1d
Kim et al. (4) Whinney et al. (7) Herman et al. (12)
Penetrating trauma with cotton tip
Intact TM, ossicular chain dislocation, pneumolabyrinth TM perforation, pneumolabyrinth, anteriorly rotated depressed stapes
Moderate SNHL 40 dB (mild conductive component, after surgical closure of TM perforation) Severe mixed HL PTA 86 dB (BC 40 dB) Mixed HL PTA 88 dB (BC 39 dB)
Severe SNHL PTA 90 dB Initially moderate mixed HL, evolved to deafness
5d
4d
32 d (late increase vestibular symptoms) 4d
2 wk 0 d (severe vestibular symptoms) 4 mo
8d 2 mo (late increase vestibular symptoms)
16 mo
11 d (also steroid therapy) 3 yr (late increase vestibular symptoms)
TM indicates tympanic membrane; SNHL, sensorineural hearing loss; CHL, conductive hearing loss; PTA, pure tone average (in dB Hearing Level at 0.5, 1.0, and 2.0 KHz); HL, hearing loss; BC, bone conduction; OW, oval window; RW, round window; perich, perichondrium.
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STAPEDIOVESTIBULAR LUXATION
587
Perilymph leakage
Sealed
Yes
Yes
Stapes deeply depressed and invisible (CT diagnosis)
None, cartilaginous columella between sealed oval window and TM
Moderate mixed hearing loss PTA 51 dB (BC 15 dB)
+
Yes
Fat
Intact, depressed, incuidal luxation
None
Deafness
-
Intact, slightly depressed
Withdrawn from vestibule into OW, cartilage columella
PTA 90 dB (BC not measurable)
=
Withdrawn from vestibule into OW Withdrawn from vestibule into OW, silastic strut between crura
Profound SNHL
=
Mixed hearing loss PTA 28 dB (BC appr 20 dB)
=
Stapedectomy, malleovestibulopexy
Mixed HL PTA 30 dB (BC 25 dB)
=
Stapedectomy, TeflonA piston on intact incus
Mild CHL PTA 25 dB
=
Stapedectomy, oval window gentamicin injection
Deaf
=
Withdrawn from vestibule, same stage modified incus interposition
Severe mixed HL evolution to PTA 77 dB (BC 38 dB)
-
Stapedectomy, TeflonA piston on intact incus
Moderate SNHL PTA 45 dB
-
Removal stapes, cartilaginous columella between sealed oval window and TM Withdrawn from vestibule, incus replaced in original position
Mixed HL 45 dB, BC not specified
Yes (OW+RW)
Fascia + fibrin glue
Stapes situation
Yes
Fat
Intact, depressed
No
Fibrin glue
Intact, depressed
No
Fascia
Yes
Yes
?
Yes
Yes
Fascia
No
Vein
Yes
Perich
Intact, deeply depressed, incuidal dislocation
Yes (OW+ RW)
Perich
Mildly anteriorly tilted, leakage adjacent to anterior crus
Yes
Connective tissue
No
Fat + perich
No
No
Yes
Fascia (OW+RW)
Yes No
Fascia (OW+RW) Fat
?
Fat
Stapes dislocation, footplate fracture and anterior crus fracture Intact, posterior dislocation, hypermobile, also after reposition, incudostapedial dislocation Intact, fully depressed, incudostapedial dislocation Depressed stapes, incudostapedial and incudomallear dislocation Deeply depressed into vestibule
Fractured crura, depressed footplate, incudostapedial dislocation Footplate fracture, depressed stapes, anterior rotation, fracture suprastructure, incudostapedial dislocation Incudostapedial dislocation, outward and downward stapedial dislocation, footplate fractured and partially disappeared Avulsed
(Stapes) intervention
BC threshold outcome
=/- (?)
PTA stable
=
Mild mixed HL PTA 25 dB (BC 13 dB)
+
PTA stable
=
PTA 23 dB (BC 10 dB)
=
?
Slightly improved mixed HL
=
?
Deaf
-
Removal of stapes, connective tissue between sealed OW and incus Removal loose posterior crus, anterior part fixed to medial wall of vestibule Cartilage columella between oval window and incus
Avulsed
Postoperative hearing
Fracture of the footplate
None
SNHL PTA 25 dB
+
Intact, depressed
Labyrinthectomy
Deaf
=
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M. BOGAERTS ET AL. TABLE 2.
Author
Cause
Stapedial luxation treated conservatively
Otoscopy/CT findings*
Hearing after trauma
Hearing at follow-up
Vestibular symptoms
Lao and Niparko (8) Penetrating trauma TM perforation, intact Moderate to profound Mild CHL PTA 30 dB Intermittent unsteadiness, with tree branch incudostapedial joint, mixed HL PTA 71 dB (BC 11 dB) resolved after 6 d pneumolabyrinth, (BC 35) stapedial luxation Hidaka et al. (9) Penetrating trauma TM perforation, Mixed HL PTA 36 dB PTA 18 dB (BC 13 dB) Vertigo subsided after 5 d with ear pick pneumolabyrinth (BC 10 dB) Hidaka et al. (9) Penetrating trauma TM perforation, Mixed HL PTA 76 dB PTA 35 dB (BC 15 dB) Vertigo subsided after 7 d with ear pick pneumolabyrinth (BC 11 dB) TM indicates tympanic membrane; CHL, conductive hearing loss; PTA, pure tone average (in dB Hearing Level at 0.5, 1.0, and 2.0 KHz); HL, hearing loss; BC, bone conduction.
position of the stapes, as well as the preoperative hearing thresholds. We describe a new technique lifting an intact and depressed stapes out of the vestibule, supporting it by means of a (silastic) strut. REFERENCES 1. Kobayashi T, Gyo K. Earpick injury of the stapes. Am J Otolaryngol 2000;21:340Y3. 2. Meriot P, Veillon F, Garcia JF, et al. CT appearances of ossicular injuries. Radiographics 1997;17:1445Y54. 3. Kagoya R, Ito K, Kashio A, Karino S, Yamasoba T. Dislocation of stapes with footplate fracture caused by indirect trauma. Ann Otol Rhinol Laryngol 2010;119:628Y30. 4. Kim SH, Kazahaya K, Handler SD. Traumatic perilymphatic fistulas in children: etiology, diagnosis and management. Int J Pediatr Otorhinolaryngol 2001;60:147Y53. 5. Sarac S, Cengel S, Sennaroglu L. Pneumolabyrinth following traumatic luxation of the stapes into the vestibule. Int J Pediatr Otorhinolaryngol 2006;70:159Y61. 6. Chujo K, Nakagawa T, Komune S. Temporal bone fracture with ossicular dislocation caused by a blow to the opposite side of the head. Auris Nasus Larynx 2008;35:273Y5. 7. Whinney DJ, Parikh AA, Brookes GB. Barotraumatic fracture of the stapes footplate. Am J Otol 1996;17:697Y9. 8. Lao WW, Niparko JK. Assessment of changes in cochlear function with pneumolabyrinth after middle ear trauma. Otol Neurotol 2007;28:1013Y7. 9. Hidaka H, Miyazaki M, Kawase T, Kobayashi T. Traumatic pneumolabyrinth: air location and hearing outcome. Otol Neurotol 2012;33:123Y31.
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