- Email: [email protected]
Isolated malleus fixation: A pediatric case series
International Journal of Pediatric Otorhinolaryngology 124 (2019) 1–5
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Isolated malleus fixation: A pediatric case series Kevin Y. Zhan a b
a,b
, Jameson K. Mattingly
a,b
, Oliver F. Adunka
T
a,b,∗
Department of Otolaryngology - Head & Neck Surgery, Division of Pediatric Otology & Hearing Program, Nationwide Children's Hospital, Columbus, OH, USA Department of Otolaryngology - Head & Neck Surgery, Division of Otology, Neurotology & Cranial Base Surgery, The Ohio State University, Columbus, OH, USA
A R T I C LE I N FO
A B S T R A C T
Keywords: Pediatric Tympanoplasty Hearing loss Malleus fixation Anterior malleolar ligament
Objectives: The goal of this review was to review our series of isolated malleus fixation in pediatric patients, a rare entity causing conductive hearing loss. Malleolar fixation is poorly described in this patient population. Methods: A retrospective review of pediatric tympanoplasties by the senior author over a four-year period was performed. Only cases with isolated fixation of the malleus were reviewed. Primary outcome of interest was postoperative hearing. Paired t-tests were used to calculate pre- and post-operative hearing outcomes. Results: Five cases were analyzed. Mean age at time of surgery was 9.1 years (range 4.4–16.0 years). Average follow-up after surgery was 13.9 months (range 4.4–31.2 months). Patients were otherwise healthy and typically presented after a failed school hearing test despite previously good hearing. Three out of five cases showed radiographic evidence of bony fixation (60%) on computerized tomography (CT). Otoscopy was unremarkable in all cases. Average procedure time was 41.2 min and consisted of transcanal tympanoplasty with excision of fixed bony segment. A significant improvement in both pre- and post-operative air bone gaps was observed (p = 0.005)., with average ABG of 14.75 dB. Conclusions: Isolated pediatric malleolar fixation is an uncommon cause of pediatric conductive hearing loss. CT scan is useful for identifying this abnormality, and surgical correction results in improved post-operative hearing outcomes, potentially obviating the need for hearing amplification.
1. Introduction Pediatric hearing loss is common and its impact can be substantial, including significant delays in speech, language, and cognitive development [1]. Types of hearing loss include sensorineural (SNHL), conductive (CHL), and mixed hearing losses (MHL). With regards to CHL and MHL, potential etiologies include acute otitis media, otitis media with effusion, cholesteatoma and chronic otitis media, and a myriad of ossicular pathologies. While otitis media and cholesteatoma have more obvious clinical signs, isolated ossicular pathologies are more difficult to diagnose. Ossicular abnormalities can manifest in a spectrum from single ossicular pathology to all three ossicles with involvement of the middle ear space. Rarely, these findings are in the setting of systemic diseases such X-linked stapes gusher syndrome, otosclerosis, and others. Malleus fixation has been reported as a rare cause of CHL, with an estimated prevalence of 0.4–1.4% in primary stapedectomies, and an unknown incidence in the general population [2–11]. Most reports on the subject are embedded within adult stapedectomy literature as a cause for primary failure; thus, studies on isolated malleus fixation are sparse, particularly in the pediatric population. Various forms of
malleus immobility such as involvement of the malleolar ligaments, posterior neck fixation to tympanic cavity, fixation to the scutum, superior malleolar ligament fixation, and adhesions to other areas of the epitympanum have been described [9,12–18]. In this study, we present five cases of isolated malleus fixation in children and report their surgical and hearing outcomes. 2. Methods A retrospective review of pediatric tympanoplasties by the senior author (OFA) was performed from years 2014–2018. Operative reports were reviewed and only cases involving isolated fixation of the malleus were included. Surgeries were performed at a freestanding children's hospital and all patients were ≤18 years old. Local Institutional Review Board approval of the study was obtained. Given the unique selection biases of tertiary referral at a large children's hospital for pediatric otologic/neurotologic care, we did not attempt to quantify the incidence of malleus fixation.
∗ Corresponding author.Department of Otolaryngology - Head & Neck Surgery, Division of Otology, Neurotology & Cranial Base Surgery, The Ohio State University, Columbus, OH, USA. E-mail address: [email protected] (O.F. Adunka).
https://doi.org/10.1016/j.ijporl.2019.05.021 Received 19 March 2019; Received in revised form 19 May 2019; Accepted 19 May 2019 Available online 22 May 2019 0165-5876/ © 2019 Elsevier B.V. All rights reserved.
International Journal of Pediatric Otorhinolaryngology 124 (2019) 1–5
No Yes 4.4 7.4 R R F F 4 5
None None
Yes None 5.8 L M 3
2.1. Patients Tympanoplasties with “malleus fixation” or “malleolar fixation” in the operative note were queried, yielding our case series. Cases with a history of ipsilateral cholesteatoma (N = 1) or other concomitant ossicular fixations (N = 2) were excluded. Overall, five patients were included in our analysis. 2.2. Audiometric data Demographic, clinical, and disease-specific variables were extracted from the medical record. Hearing outcomes were the primary outcome of interest, with a specific interest in air-bone gap (ABG) pure tone average (PTA) thresholds and air conduction PTAs. PTAs were calculated using 0.5, 1, 2, and 4 kHz for air and bone conducation thresholds. The best (lowest threshold) bone-line was used for all ABG calculations. If multiple pre-operative audiograms were available, the smallest ABG value was recorded. If audiometry was incomplete (e.g. child fatigues before completion of all bone threshold testing), a PTA was calculated from available values.
Abbreviations: RAOM (recurrent acute otitis media); PE (pressure equalization); CHL (conductive hearing loss); CT (computerized tomography); ABG (Air Bone Gap).
Isolated malleolar, divided with CO2 Laser. Partially ossified malleolar ligament, bar of bone at notch of Rivinus curetted away Bony fixation just superior to the anterior and lateral malleolar ligaments, curetted away Isolated malleolar fixation Malleolar ligament ossification + surface of malleus neck fused to bone of Prussak's space - drilled 1 mm diamond No Yes
Presents after failed school hearing screen Presents after previous L tympanoplasty at different institution and also PE tubes x1. Slowly developed L CHL Presents after prior adenotonsillectomy, no otologic history. Slowly developed CHL. Presents after failed school hearing screen, only 1 ear infection in past. Presents after failed school hearing screen, no previous ear infections None RAOM L L M M 1 2
16.0 11.9
CT Evidence of Malleus Fixation Clinical Presentation Side of Fixation Sex Case
Table 1 Case series.
Age at Surgery
Otologic History
Surgical Comments
K.Y. Zhan, et al.
2.3. Imaging High resolution temporal bone computed tomography (CT) was obtained pre-operatively in all patients. Stapedius tendon reflexes were inconsistently obtained and thus are not reported; nonetheless, absent stapedius reflexes are not consistently found in a series of adult patients [9]. 2.4. Surgical procedure All patients underwent a transcanal tympanoplasty under general anesthesia. A tympanomeatal flap was elevated and extended over the tympanosquamous suture line antero-superiorly. The middle ear was then entered in the posterior inferior quadrant and the chorda tympani was identified and preserved. The tympanomeatal flap was extended superiorly into the pars flaccia. A transcanal atticotomy was performed. Anterior dissection was continued until the neck of the malleus was visible. The tympanic membrane was then dissected off the superior aspect of the malleus and the short process of the malleus. The visible malleolar ligaments were then palpated and the overall mobility of the ossicular chain was evaluated. When an ossified malleolar ligament was present, the ligament was cut with either sharp instruments or the CO2 laser. It should be noted that we do not make a distinction between anterior and lateral ligament fixation, as it is clinically difficult to differentiate the two. In cases where the fixation of the anterior or lateral malleolar ligament was soft, the site of ankylosis was presumed more superior. Then, the bone obscuring the pathological fixation was curetted and the ankylosis was repaired similar to anterior or lateral malleolar ligament fixation. Following dissection, mobility of the ossicluar chain was re-tested and the tympanic membrane was returned. An edited video of this procedure is available online, included as a supplement. 2.5. Statistical analysis Paired samples t-tests were used to compare mean PTAs before and after surgery. An alpha of < 0.05 was considered significant. All analyses were performed in SPSS statistical software version 25 (IBM SPSS Inc., Chicago). 3. Results 3.1. Patient characteristics Clinical, hearing, and surgical features of our five patients in this 2
International Journal of Pediatric Otorhinolaryngology 124 (2019) 1–5
K.Y. Zhan, et al.
Table 2 Hearing outcomes. Case
ABG
500 Hz (dB)
1000 Hz (dB)
2000 Hz (dB)
4000 Hz (dB)
Mean ABG (dB)
#1
Pre-op Post-op Pre-op Post-op Pre-op Post-op Pre-op Post-op Pre-op Post-op
35 30 35 15 35 15 30 0 35 0
30 20 35 15 30 10 25 0 30 0
0 0 30 15 15 10 10 0 15 0
20 10 30 15 15 15 5 0 5 0
21.25 15 32.5 15 23.75 12.5 17.5 0 21.25 0
#2 #3 #4 #5
Abbreviations: ABG, Air Bone Gap.
case series are shown in Tables 1 and 2. Average age at the time of surgery was 9.1 years (range 4.4–16.0 years). Average follow-up after surgery was 13.9 months (range 4.4–31.2 months). All patients were without significant comorbidity or genetic syndromes. Only one patient had a history of recurrent acute otitis media. The typical clinical presentation of patients in our series was a persistent CHL found after a failed school hearing screen, typically without any significant otologic history or concerning otologic exam findings. All five patients passed their newborn hearing screening. Three out of five cases (60%) showed obvious evidence of bony fixation of the malleolar head or neck on pre-operative CT. Fig. 1 shows demonstrative CT scan images showing lateral fixation of the malleus head to the bony scutum, though this was not the pattern in all cases. Fig. 2 is a demonstrative intraoperative picture showing isolated malleolar ligament bony fixation (Case #4). This ligament either represents the anterior or lateral malleolar ligament, as differentiating the two clinically is difficult. Video of case #4 is available in an online supplement. Average procedure time was 41.2 min (standard deviation 7.9 min).
Fig. 2. Intraoperative photo of isolated right malleus fixation under tympanomeatal flap (case #4).
stapedectomy studies as a rare cause for primary stapedectomy failure, and little has been written about malleus fixation in the pediatric population [2–11]. This is particularly important in pediatrics due to the long-term deficits in speech, language, and cognitive function that have been associated with hearing loss. This report sought to present a series of pediatric patients with isolated malleus fixation, with specific emphasis on audiological outcome and clinical characteristics. In this report, we have described five pediatric cases of isolated malleus fixation. Despite a variable age of presentation (4–16 years old), the majority presented in similar fashion after a failed school hearing screen (80%), and ultimately had CT scan findings showing malleolar head fixation (60%). All patients were without significant past medical history, and only case #2 had a history of recurrent otitis media with previous tympanostomy tube insertion and tympanoplasty from an outside institution. In almost cases (80%) there was a
3. 2 hearing outcomes With exception of case #2, all pre-operative audiograms had predominantly low-frequency hearing loss with a rising slope in the middle and high frequencies. Case #2 demonstrated a flat audiogram. There were no cases of bilateral CHL. Mean pre- and post-operative ABG were 23.25 dB and 8.5 dB (average difference of 14.75 dB), respectively; a significant change in mean ABG was observed using a paired-samples ttest (p = 0.005). 4. Discussion The majority of literature on malleus fixation is embedded in adult
Fig. 1. Demonstrative computerized tomography (CT) images showing lateral fixation of the malleolar head (Case #5). Axial and coronal CT images of case #5, right ear, showing malleus head fixation to the scutum (red arrows). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)
3
International Journal of Pediatric Otorhinolaryngology 124 (2019) 1–5
K.Y. Zhan, et al.
outcome are at higher risk to being lost to follow-up unless their hearing changes. The actual incidence of isolated malleus fixation remains difficult to estimate with a small case series as definitive diagnosis requires parents consenting their child to undergo elective surgery. Large, multi-institutional efforts are likely needed to better characterize isolated malleus fixation across multiple practice settings and referral bases. Nonetheless, our study is the first to characterize a series of isolated malleus fixation in the pediatric population.
predominantly low-frequency CHL. The anterior or lateral malleolar ligament was involved in 80%, and there was no evidence of otosclerosis or tympanosclerosis in any case. Surgery consisted of a transcanal middle ear exploration with assessment of the ossicles and excision of the bony fixation with a variety of techniques (CO2 laser, bone curette, diamond drill, or a combination of these methods). More importantly, surgical correction resulted in a significant improvement in post-operative hearing (p = 0.039) with 80% cases returning to ≤ 20 dB air conduction PTA (0% pre-operatively). Powers et al. describe in their adult series at the House institute that their preferred method for malleus fixation in a non-otosclerotic ear is to remove the malleus head and perform an incus interposition graft; however, no surgical or hearing results specific to this technique are reported [8]. Although we did not use endoscopes in our series, Zhu et al. have described the feasibility of endoscopic transcanal management of pediatric congenital fixation in seven patients [19]. As discussed previously, little literature exists discussing malleus fixation, and outside of an association with otosclerosis, the etiopathogenesis of isolated malleus fixation remains poorly understood [20]. Diagnoses such as Treacher Collins, Goldenhar, and BranchialOto-Renal syndromes are associated with ossicular abnormalities, though not exclusively with malleus fixation [19]. Some authors attribute the process to progressive malleus ligament ankylosis (akin to chronic arthritic changes) with a predominant presentation in older populations [9]. Oktay et al. compared the rate of anterior mallear ligament (AML) hyalinization in three cohorts of adult temporal bones: those with a known history of otosclerosis with stapes fixation, otosclerosis without stapes fixation, and age-matched controls; however, they were not able to find a difference in distribution of AML hyalinization across these cohorts [15]. Notably, severity of hyalinization was not associated with degree of hearing loss, and the four cases of malleus head fixation were all to the lateral epitympanum and in patients with stapedial otosclerosis. Ritter described three adult cases of speculated congenital isolated malleus fixation in the absence of inflammatory ear disease or trauma [14]. All three of these patients had a bony bar fixing the malleus head to a bony septation within the epitympanum (two had anterior epitympanic fixation and one had a scutal fixation). It was speculated that these could have been the result of incomplete mesenchymal resorption in the middle ear cleft during late gestational development, resulting in a remnant bony bar to the ossicles [21]. As all patients in our case series initially had normal hearing, they may have had a similar pathophysiology and represent a progressive fixation of a predisposed embryologic anomaly. Average pre-operative air-bone gap PTA in our series was 23.25 dB, similar to what is predicted (15–30 dB) in simulated malleus fixation studies using laser doppler vibrometry [5,15]. While various techniques have been described for optimally managing isolated malleus fixation [8,9,14,20], we achieved good post-operative hearing results by excising the bony fixation without additional manipulation or removal of ossicles. In each case, restoration of normal ossicular chain mobility was achieved, confirmed intraoperatively with palpation and audiometrically by improved PTAs. In a series of stapedial otosclerosis patients, Powers et al. reported a rate of 57% re-fixation rate with malleolysis alone causing them to later abandoned this technique in favor of malleus head removal and incus repositioning [8]. However, their observation of re-fixation could simply be the result of underlying otosclerosis, which was unlikely the underlying etiology in our case series. There was one patient in our case series that failed to have a significant hearing benefit (> 10 dB mean ABG improvement). Unfortunately, this patient was lost to follow-up and we could not pinpoint a cause without repeat evaluation and CT scan; it is possible that he may have had some partial refixation after surgery. This study is limited as a small case series with a variable follow-up period (4.4–31.2 months). As such, re-fixation potential and long-term hearing outcomes cannot be assessed without significant long-term follow-up; unfortunately, patients with a good post-surgical hearing
5. Conclusion Isolated pediatric malleolar fixation is an uncommon cause of CHL that typically presents in otherwise healthy children without a significant history of otologic disease and a mild CHL. CT scan is useful for identifying this abnormality, and surgical correction results in improved post-operative hearing outcomes, potentially obviating the need for hearing amplification. Disclosures Oliver F. Adunka is consultant for MED-EL Corporation, Advanced Genetics Technologies Corporation (AGTC), Spiral Therapeutics, and Advanced Bionics Corporations and receives research support from Cochlear Americas, MED-EL Corporation, and Advanced Bionics Corporation. Oliver F. Adunka is the president of Advanced Cochlear Diagnostics. Funding None. Appendix A. Supplementary data Supplementary data to this article can be found online at https:// doi.org/10.1016/j.ijporl.2019.05.021. References [1] J.B. Tomblin, M. Harrison, S.E. Ambrose, E.A. Walker, J.J. Oleson, M.P. Moeller, Language outcomes in young children with mild to severe hearing loss, Ear Hear. 36 (Suppl 1) (2015) 76S–91S 2015. [2] U. Fisch, G.O. Acar, A.M. Huber, Malleostapedotomy in revision surgery for otosclerosis, Otol. Neurotol. 22 (2001) 776–785 2001. [3] M.S. Marion, R. Hinojosa, Temporal bone histopathology: fixed malleus, Am. J. Otolaryngol. 11 (1990) 205–206 1990. [4] J.J. Shea Jr., How I do primary and revision stapedectomy, Am. J. Otol. 15 (1994) 71–73 1994. [5] A. Huber, T. Koike, H. Wada, V. Nandapalan, U. Fisch, Fixation of the anterior mallear ligament: diagnosis and consequences for hearing results in stapes surgery, Ann. Otol. Rhinol. Laryngol. 112 (2003) 348–355 2003. [6] Y. Vaisbuch, D.K. Hosseini, J.S. Oghalai, Otosclerosis with concomitant anterior malleolar ligament fixation, Otol. Neurotol. 39 (2018) e58–e59 2018. [7] R. Vincent, N.M. Sperling, J. Oates, M. Jindal, Surgical findings and long-term hearing results in 3,050 stapedotomies for primary otosclerosis: a prospective study with the otology-neurotology database, Otol. Neurotol. 27 (2006) S25–S47 2006. [8] W.H. Powers, J.L. Sheehy, H.P. House, The fixed malleus head. A report of 35 cases, Arch. Otolaryngol. 85 (1967) 177–181 1967. [9] C.N. Moon Jr., M.J. Hahn, Primary malleus fixation: diagnosis and treatment, The Laryngoscope 91 (1981) 1298–1307 1981. [10] F.R. Guilford, Personal experiences with the Shea oval window-vein graft technique, The Laryngoscope 71 (1961) 484–503 1961. [11] W.H. Lippy, A.G. Schuring, M. Ziv, Stapedectomy for otosclerosis with malleus fixation, Arch. Otolaryngol. 104 (1978) 388–389 1978. [12] M. Bruzzo, F. Braccini, F. Caces, J.M. Vallicioni, A. Chays, J. Magnan, Fixed mallear head syndrome, Ann. Otolaryngol. Chir. Cervicofac. 115 (1998) 279–283 1998. [13] C. Martin, A.P. Timoshenko, J.M. Dumollard, S. Tringali, M. Peoc'h, J.M. Prades, Malleus head fixation: histopathology revisited, Acta Otolaryngol. 126 (2006) 353–357 2006. [14] F.N. Ritter, The histopathology of the congenital fixed malleus syndrome, The Laryngoscope 81 (1971) 1304–1313 1971. [15] M.F. Oktay, S. Cureoglu, P.A. Schachern, E. Gulbahce, M.M. Paparella, H. Hayasi, Histologic changes in the anterior mallear ligament and the head of the malleus in otosclerosis, Otolaryngol. Head Neck Surg. 134 (2006) 232–235 2006. [16] H.H. Nakajima, M.E. Ravicz, J.J. Rosowski, W.T. Peake, S.N. Merchant,
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International Journal of Pediatric Otorhinolaryngology 124 (2019) 1–5
K.Y. Zhan, et al. Experimental and clinical studies of malleus fixation, The Laryngoscope 115 (2005) 147–154 2005. [17] C. Dai, T. Cheng, M.W. Wood, R.Z. Gan, Fixation and detachment of superior and anterior malleolar ligaments in human middle ear: experiment and modeling, Hear. Res. 230 (2007) 24–33 2007. [18] Y. Kurosaki, Y.O. Tanaka, Y. Itai, Malleus bar as a rare cause of congenital malleus fixation: CT demonstration, AJNR Am. J. Neuroradiol. 19 (1998) 1229–1230 1998.
[19] V.F. Zhu, Y.F. Kou, K.H. Lee, J.W. Kutz Jr., B. Isaacson, Transcanal endoscopic ear surgery for the management of congenital ossicular fixation, Otol. Neurotol. 37 (2016) 1071–1076 2016. [20] C. Martin, A. Oletski, J.M. Prades, Surgery of idiopathic malleus fixation, Otol. Neurotol. 30 (2009) 165–169 2009. [21] B. Proctor, The development of the middle ear spaces and their surgical significance, J. Laryngol. Otol. 78 (1964) 631–648 1964.
5
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Isolated malleus fixation: A pediatric case series Kevin Y. Zhan a b
a,b
, Jameson K. Mattingly
a,b
, Oliver F. Adunka
T
a,b,∗
Department of Otolaryngology - Head & Neck Surgery, Division of Pediatric Otology & Hearing Program, Nationwide Children's Hospital, Columbus, OH, USA Department of Otolaryngology - Head & Neck Surgery, Division of Otology, Neurotology & Cranial Base Surgery, The Ohio State University, Columbus, OH, USA
A R T I C LE I N FO
A B S T R A C T
Keywords: Pediatric Tympanoplasty Hearing loss Malleus fixation Anterior malleolar ligament
Objectives: The goal of this review was to review our series of isolated malleus fixation in pediatric patients, a rare entity causing conductive hearing loss. Malleolar fixation is poorly described in this patient population. Methods: A retrospective review of pediatric tympanoplasties by the senior author over a four-year period was performed. Only cases with isolated fixation of the malleus were reviewed. Primary outcome of interest was postoperative hearing. Paired t-tests were used to calculate pre- and post-operative hearing outcomes. Results: Five cases were analyzed. Mean age at time of surgery was 9.1 years (range 4.4–16.0 years). Average follow-up after surgery was 13.9 months (range 4.4–31.2 months). Patients were otherwise healthy and typically presented after a failed school hearing test despite previously good hearing. Three out of five cases showed radiographic evidence of bony fixation (60%) on computerized tomography (CT). Otoscopy was unremarkable in all cases. Average procedure time was 41.2 min and consisted of transcanal tympanoplasty with excision of fixed bony segment. A significant improvement in both pre- and post-operative air bone gaps was observed (p = 0.005)., with average ABG of 14.75 dB. Conclusions: Isolated pediatric malleolar fixation is an uncommon cause of pediatric conductive hearing loss. CT scan is useful for identifying this abnormality, and surgical correction results in improved post-operative hearing outcomes, potentially obviating the need for hearing amplification.
1. Introduction Pediatric hearing loss is common and its impact can be substantial, including significant delays in speech, language, and cognitive development [1]. Types of hearing loss include sensorineural (SNHL), conductive (CHL), and mixed hearing losses (MHL). With regards to CHL and MHL, potential etiologies include acute otitis media, otitis media with effusion, cholesteatoma and chronic otitis media, and a myriad of ossicular pathologies. While otitis media and cholesteatoma have more obvious clinical signs, isolated ossicular pathologies are more difficult to diagnose. Ossicular abnormalities can manifest in a spectrum from single ossicular pathology to all three ossicles with involvement of the middle ear space. Rarely, these findings are in the setting of systemic diseases such X-linked stapes gusher syndrome, otosclerosis, and others. Malleus fixation has been reported as a rare cause of CHL, with an estimated prevalence of 0.4–1.4% in primary stapedectomies, and an unknown incidence in the general population [2–11]. Most reports on the subject are embedded within adult stapedectomy literature as a cause for primary failure; thus, studies on isolated malleus fixation are sparse, particularly in the pediatric population. Various forms of
malleus immobility such as involvement of the malleolar ligaments, posterior neck fixation to tympanic cavity, fixation to the scutum, superior malleolar ligament fixation, and adhesions to other areas of the epitympanum have been described [9,12–18]. In this study, we present five cases of isolated malleus fixation in children and report their surgical and hearing outcomes. 2. Methods A retrospective review of pediatric tympanoplasties by the senior author (OFA) was performed from years 2014–2018. Operative reports were reviewed and only cases involving isolated fixation of the malleus were included. Surgeries were performed at a freestanding children's hospital and all patients were ≤18 years old. Local Institutional Review Board approval of the study was obtained. Given the unique selection biases of tertiary referral at a large children's hospital for pediatric otologic/neurotologic care, we did not attempt to quantify the incidence of malleus fixation.
∗ Corresponding author.Department of Otolaryngology - Head & Neck Surgery, Division of Otology, Neurotology & Cranial Base Surgery, The Ohio State University, Columbus, OH, USA. E-mail address: [email protected] (O.F. Adunka).
https://doi.org/10.1016/j.ijporl.2019.05.021 Received 19 March 2019; Received in revised form 19 May 2019; Accepted 19 May 2019 Available online 22 May 2019 0165-5876/ © 2019 Elsevier B.V. All rights reserved.
International Journal of Pediatric Otorhinolaryngology 124 (2019) 1–5
No Yes 4.4 7.4 R R F F 4 5
None None
Yes None 5.8 L M 3
2.1. Patients Tympanoplasties with “malleus fixation” or “malleolar fixation” in the operative note were queried, yielding our case series. Cases with a history of ipsilateral cholesteatoma (N = 1) or other concomitant ossicular fixations (N = 2) were excluded. Overall, five patients were included in our analysis. 2.2. Audiometric data Demographic, clinical, and disease-specific variables were extracted from the medical record. Hearing outcomes were the primary outcome of interest, with a specific interest in air-bone gap (ABG) pure tone average (PTA) thresholds and air conduction PTAs. PTAs were calculated using 0.5, 1, 2, and 4 kHz for air and bone conducation thresholds. The best (lowest threshold) bone-line was used for all ABG calculations. If multiple pre-operative audiograms were available, the smallest ABG value was recorded. If audiometry was incomplete (e.g. child fatigues before completion of all bone threshold testing), a PTA was calculated from available values.
Abbreviations: RAOM (recurrent acute otitis media); PE (pressure equalization); CHL (conductive hearing loss); CT (computerized tomography); ABG (Air Bone Gap).
Isolated malleolar, divided with CO2 Laser. Partially ossified malleolar ligament, bar of bone at notch of Rivinus curetted away Bony fixation just superior to the anterior and lateral malleolar ligaments, curetted away Isolated malleolar fixation Malleolar ligament ossification + surface of malleus neck fused to bone of Prussak's space - drilled 1 mm diamond No Yes
Presents after failed school hearing screen Presents after previous L tympanoplasty at different institution and also PE tubes x1. Slowly developed L CHL Presents after prior adenotonsillectomy, no otologic history. Slowly developed CHL. Presents after failed school hearing screen, only 1 ear infection in past. Presents after failed school hearing screen, no previous ear infections None RAOM L L M M 1 2
16.0 11.9
CT Evidence of Malleus Fixation Clinical Presentation Side of Fixation Sex Case
Table 1 Case series.
Age at Surgery
Otologic History
Surgical Comments
K.Y. Zhan, et al.
2.3. Imaging High resolution temporal bone computed tomography (CT) was obtained pre-operatively in all patients. Stapedius tendon reflexes were inconsistently obtained and thus are not reported; nonetheless, absent stapedius reflexes are not consistently found in a series of adult patients [9]. 2.4. Surgical procedure All patients underwent a transcanal tympanoplasty under general anesthesia. A tympanomeatal flap was elevated and extended over the tympanosquamous suture line antero-superiorly. The middle ear was then entered in the posterior inferior quadrant and the chorda tympani was identified and preserved. The tympanomeatal flap was extended superiorly into the pars flaccia. A transcanal atticotomy was performed. Anterior dissection was continued until the neck of the malleus was visible. The tympanic membrane was then dissected off the superior aspect of the malleus and the short process of the malleus. The visible malleolar ligaments were then palpated and the overall mobility of the ossicular chain was evaluated. When an ossified malleolar ligament was present, the ligament was cut with either sharp instruments or the CO2 laser. It should be noted that we do not make a distinction between anterior and lateral ligament fixation, as it is clinically difficult to differentiate the two. In cases where the fixation of the anterior or lateral malleolar ligament was soft, the site of ankylosis was presumed more superior. Then, the bone obscuring the pathological fixation was curetted and the ankylosis was repaired similar to anterior or lateral malleolar ligament fixation. Following dissection, mobility of the ossicluar chain was re-tested and the tympanic membrane was returned. An edited video of this procedure is available online, included as a supplement. 2.5. Statistical analysis Paired samples t-tests were used to compare mean PTAs before and after surgery. An alpha of < 0.05 was considered significant. All analyses were performed in SPSS statistical software version 25 (IBM SPSS Inc., Chicago). 3. Results 3.1. Patient characteristics Clinical, hearing, and surgical features of our five patients in this 2
International Journal of Pediatric Otorhinolaryngology 124 (2019) 1–5
K.Y. Zhan, et al.
Table 2 Hearing outcomes. Case
ABG
500 Hz (dB)
1000 Hz (dB)
2000 Hz (dB)
4000 Hz (dB)
Mean ABG (dB)
#1
Pre-op Post-op Pre-op Post-op Pre-op Post-op Pre-op Post-op Pre-op Post-op
35 30 35 15 35 15 30 0 35 0
30 20 35 15 30 10 25 0 30 0
0 0 30 15 15 10 10 0 15 0
20 10 30 15 15 15 5 0 5 0
21.25 15 32.5 15 23.75 12.5 17.5 0 21.25 0
#2 #3 #4 #5
Abbreviations: ABG, Air Bone Gap.
case series are shown in Tables 1 and 2. Average age at the time of surgery was 9.1 years (range 4.4–16.0 years). Average follow-up after surgery was 13.9 months (range 4.4–31.2 months). All patients were without significant comorbidity or genetic syndromes. Only one patient had a history of recurrent acute otitis media. The typical clinical presentation of patients in our series was a persistent CHL found after a failed school hearing screen, typically without any significant otologic history or concerning otologic exam findings. All five patients passed their newborn hearing screening. Three out of five cases (60%) showed obvious evidence of bony fixation of the malleolar head or neck on pre-operative CT. Fig. 1 shows demonstrative CT scan images showing lateral fixation of the malleus head to the bony scutum, though this was not the pattern in all cases. Fig. 2 is a demonstrative intraoperative picture showing isolated malleolar ligament bony fixation (Case #4). This ligament either represents the anterior or lateral malleolar ligament, as differentiating the two clinically is difficult. Video of case #4 is available in an online supplement. Average procedure time was 41.2 min (standard deviation 7.9 min).
Fig. 2. Intraoperative photo of isolated right malleus fixation under tympanomeatal flap (case #4).
stapedectomy studies as a rare cause for primary stapedectomy failure, and little has been written about malleus fixation in the pediatric population [2–11]. This is particularly important in pediatrics due to the long-term deficits in speech, language, and cognitive function that have been associated with hearing loss. This report sought to present a series of pediatric patients with isolated malleus fixation, with specific emphasis on audiological outcome and clinical characteristics. In this report, we have described five pediatric cases of isolated malleus fixation. Despite a variable age of presentation (4–16 years old), the majority presented in similar fashion after a failed school hearing screen (80%), and ultimately had CT scan findings showing malleolar head fixation (60%). All patients were without significant past medical history, and only case #2 had a history of recurrent otitis media with previous tympanostomy tube insertion and tympanoplasty from an outside institution. In almost cases (80%) there was a
3. 2 hearing outcomes With exception of case #2, all pre-operative audiograms had predominantly low-frequency hearing loss with a rising slope in the middle and high frequencies. Case #2 demonstrated a flat audiogram. There were no cases of bilateral CHL. Mean pre- and post-operative ABG were 23.25 dB and 8.5 dB (average difference of 14.75 dB), respectively; a significant change in mean ABG was observed using a paired-samples ttest (p = 0.005). 4. Discussion The majority of literature on malleus fixation is embedded in adult
Fig. 1. Demonstrative computerized tomography (CT) images showing lateral fixation of the malleolar head (Case #5). Axial and coronal CT images of case #5, right ear, showing malleus head fixation to the scutum (red arrows). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)
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outcome are at higher risk to being lost to follow-up unless their hearing changes. The actual incidence of isolated malleus fixation remains difficult to estimate with a small case series as definitive diagnosis requires parents consenting their child to undergo elective surgery. Large, multi-institutional efforts are likely needed to better characterize isolated malleus fixation across multiple practice settings and referral bases. Nonetheless, our study is the first to characterize a series of isolated malleus fixation in the pediatric population.
predominantly low-frequency CHL. The anterior or lateral malleolar ligament was involved in 80%, and there was no evidence of otosclerosis or tympanosclerosis in any case. Surgery consisted of a transcanal middle ear exploration with assessment of the ossicles and excision of the bony fixation with a variety of techniques (CO2 laser, bone curette, diamond drill, or a combination of these methods). More importantly, surgical correction resulted in a significant improvement in post-operative hearing (p = 0.039) with 80% cases returning to ≤ 20 dB air conduction PTA (0% pre-operatively). Powers et al. describe in their adult series at the House institute that their preferred method for malleus fixation in a non-otosclerotic ear is to remove the malleus head and perform an incus interposition graft; however, no surgical or hearing results specific to this technique are reported [8]. Although we did not use endoscopes in our series, Zhu et al. have described the feasibility of endoscopic transcanal management of pediatric congenital fixation in seven patients [19]. As discussed previously, little literature exists discussing malleus fixation, and outside of an association with otosclerosis, the etiopathogenesis of isolated malleus fixation remains poorly understood [20]. Diagnoses such as Treacher Collins, Goldenhar, and BranchialOto-Renal syndromes are associated with ossicular abnormalities, though not exclusively with malleus fixation [19]. Some authors attribute the process to progressive malleus ligament ankylosis (akin to chronic arthritic changes) with a predominant presentation in older populations [9]. Oktay et al. compared the rate of anterior mallear ligament (AML) hyalinization in three cohorts of adult temporal bones: those with a known history of otosclerosis with stapes fixation, otosclerosis without stapes fixation, and age-matched controls; however, they were not able to find a difference in distribution of AML hyalinization across these cohorts [15]. Notably, severity of hyalinization was not associated with degree of hearing loss, and the four cases of malleus head fixation were all to the lateral epitympanum and in patients with stapedial otosclerosis. Ritter described three adult cases of speculated congenital isolated malleus fixation in the absence of inflammatory ear disease or trauma [14]. All three of these patients had a bony bar fixing the malleus head to a bony septation within the epitympanum (two had anterior epitympanic fixation and one had a scutal fixation). It was speculated that these could have been the result of incomplete mesenchymal resorption in the middle ear cleft during late gestational development, resulting in a remnant bony bar to the ossicles [21]. As all patients in our case series initially had normal hearing, they may have had a similar pathophysiology and represent a progressive fixation of a predisposed embryologic anomaly. Average pre-operative air-bone gap PTA in our series was 23.25 dB, similar to what is predicted (15–30 dB) in simulated malleus fixation studies using laser doppler vibrometry [5,15]. While various techniques have been described for optimally managing isolated malleus fixation [8,9,14,20], we achieved good post-operative hearing results by excising the bony fixation without additional manipulation or removal of ossicles. In each case, restoration of normal ossicular chain mobility was achieved, confirmed intraoperatively with palpation and audiometrically by improved PTAs. In a series of stapedial otosclerosis patients, Powers et al. reported a rate of 57% re-fixation rate with malleolysis alone causing them to later abandoned this technique in favor of malleus head removal and incus repositioning [8]. However, their observation of re-fixation could simply be the result of underlying otosclerosis, which was unlikely the underlying etiology in our case series. There was one patient in our case series that failed to have a significant hearing benefit (> 10 dB mean ABG improvement). Unfortunately, this patient was lost to follow-up and we could not pinpoint a cause without repeat evaluation and CT scan; it is possible that he may have had some partial refixation after surgery. This study is limited as a small case series with a variable follow-up period (4.4–31.2 months). As such, re-fixation potential and long-term hearing outcomes cannot be assessed without significant long-term follow-up; unfortunately, patients with a good post-surgical hearing
5. Conclusion Isolated pediatric malleolar fixation is an uncommon cause of CHL that typically presents in otherwise healthy children without a significant history of otologic disease and a mild CHL. CT scan is useful for identifying this abnormality, and surgical correction results in improved post-operative hearing outcomes, potentially obviating the need for hearing amplification. Disclosures Oliver F. Adunka is consultant for MED-EL Corporation, Advanced Genetics Technologies Corporation (AGTC), Spiral Therapeutics, and Advanced Bionics Corporations and receives research support from Cochlear Americas, MED-EL Corporation, and Advanced Bionics Corporation. Oliver F. Adunka is the president of Advanced Cochlear Diagnostics. Funding None. Appendix A. Supplementary data Supplementary data to this article can be found online at https:// doi.org/10.1016/j.ijporl.2019.05.021. References [1] J.B. Tomblin, M. Harrison, S.E. Ambrose, E.A. Walker, J.J. Oleson, M.P. Moeller, Language outcomes in young children with mild to severe hearing loss, Ear Hear. 36 (Suppl 1) (2015) 76S–91S 2015. [2] U. Fisch, G.O. Acar, A.M. Huber, Malleostapedotomy in revision surgery for otosclerosis, Otol. Neurotol. 22 (2001) 776–785 2001. [3] M.S. Marion, R. Hinojosa, Temporal bone histopathology: fixed malleus, Am. J. Otolaryngol. 11 (1990) 205–206 1990. [4] J.J. Shea Jr., How I do primary and revision stapedectomy, Am. J. Otol. 15 (1994) 71–73 1994. [5] A. Huber, T. Koike, H. Wada, V. Nandapalan, U. Fisch, Fixation of the anterior mallear ligament: diagnosis and consequences for hearing results in stapes surgery, Ann. Otol. Rhinol. Laryngol. 112 (2003) 348–355 2003. [6] Y. Vaisbuch, D.K. Hosseini, J.S. Oghalai, Otosclerosis with concomitant anterior malleolar ligament fixation, Otol. Neurotol. 39 (2018) e58–e59 2018. [7] R. Vincent, N.M. Sperling, J. Oates, M. Jindal, Surgical findings and long-term hearing results in 3,050 stapedotomies for primary otosclerosis: a prospective study with the otology-neurotology database, Otol. Neurotol. 27 (2006) S25–S47 2006. [8] W.H. Powers, J.L. Sheehy, H.P. House, The fixed malleus head. A report of 35 cases, Arch. Otolaryngol. 85 (1967) 177–181 1967. [9] C.N. Moon Jr., M.J. Hahn, Primary malleus fixation: diagnosis and treatment, The Laryngoscope 91 (1981) 1298–1307 1981. [10] F.R. Guilford, Personal experiences with the Shea oval window-vein graft technique, The Laryngoscope 71 (1961) 484–503 1961. [11] W.H. Lippy, A.G. Schuring, M. Ziv, Stapedectomy for otosclerosis with malleus fixation, Arch. Otolaryngol. 104 (1978) 388–389 1978. [12] M. Bruzzo, F. Braccini, F. Caces, J.M. Vallicioni, A. Chays, J. Magnan, Fixed mallear head syndrome, Ann. Otolaryngol. Chir. Cervicofac. 115 (1998) 279–283 1998. [13] C. Martin, A.P. Timoshenko, J.M. Dumollard, S. Tringali, M. Peoc'h, J.M. Prades, Malleus head fixation: histopathology revisited, Acta Otolaryngol. 126 (2006) 353–357 2006. [14] F.N. Ritter, The histopathology of the congenital fixed malleus syndrome, The Laryngoscope 81 (1971) 1304–1313 1971. [15] M.F. Oktay, S. Cureoglu, P.A. Schachern, E. Gulbahce, M.M. Paparella, H. Hayasi, Histologic changes in the anterior mallear ligament and the head of the malleus in otosclerosis, Otolaryngol. Head Neck Surg. 134 (2006) 232–235 2006. [16] H.H. Nakajima, M.E. Ravicz, J.J. Rosowski, W.T. Peake, S.N. Merchant,
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