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Atypical presentation of intracochlear schwannoma in a child
International Journal of Pediatric Otorhinolaryngology Extra 5 (2010) 186–189
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology Extra journal homepage: www.elsevier.com/locate/ijporl
Case report
Atypical presentation of intracochlear schwannoma in a child Marilyn Neault a,b, Guangwei Zhou a,b,*, Margaret Kenna a,b, Dennis Poe a,b a b
Department of Otolaryngology and Communication Enhancement, Children’s Hospital Boston, United States Department of Otology and Laryngology, Harvard Medical School, United States
A R T I C L E I N F O
A B S T R A C T
Article history: Received 20 August 2009 Received in revised form 5 October 2009 Accepted 8 October 2009 Available online 7 November 2009
Intracochlear schwannoma (ICS) is a rare tumor that can cause significant hearing loss. Previous clinical reports on ICS have described this disease in adults. We present a pediatric patient with left-sided ICS who initially presented with a mild conductive hearing loss. We demonstrate the progression of the hearing loss over a span of several years through serial audiograms, as well as the process of diagnosis and treatment. This rare and unique case demonstrates that ICS can be found in young children. ß 2009 Elsevier Ireland Ltd. All rights reserved.
Keywords: Intracochlear schwannoma (ICS) Conductive hearing loss (CHL) Word recognition score (WRS)
1. Introduction
2. Case report
While vestibular schwannoma (formerly acoustic neuroma) is one of the most commonly seen benign intracranial tumors, intracochlear schwannoma (ICS) is relatively rare [1–4]. The first case of ICS was diagnosed by Nager in 1917 during an autopsy of a deaf patient [5]. Nowadays, with the improvements in contemporary medical imaging technology, the clinical diagnosis of ICS has become possible. Nonetheless, an extremely small number of ICS have been reported in the literature [5–7]. To the best of our knowledge, no ICS in a child has ever been reported. The early symptoms or complaints of ICS are often auditoryrelated, such as unilateral hearing loss and/or tinnitus [1,5,7,8]. The hearing loss is usually sensorineural, typically along with poor speech recognition ability. Additional audiologic evaluation, such as acoustic reflexes and auditory brainstem response testing, may be helpful; however, the definitive diagnosis of ICS requires Magnetic Resonance Imaging (MRI) with gadolinium contrast [3,4,6,9,10]. In this report, we present one case of ICS in a teenage girl who has an unusual history of hearing loss and an interesting process that ultimately led to a diagnosis. Our objective is to raise awareness of ICS in children and demonstrate how to appropriately diagnose and manage this rare neoplasm.
A 13-year-old girl was referred to our pediatric otolaryngology clinic for further evaluation of left-sided hearing loss. She had an uncomplicated medical history and had no complaints of tinnitus, dizziness or facial weakness. She did have a history of otitis media with effusion and underwent myringotomy with tubes at age 3 years. Results of otologic and neurologic exam in the pediatric otolaryngology outpatient clinic were unremarkable. Her earliest audiogram available was obtained in 1993 when she was 4 years old and is shown in Fig. 1A. She had normal pure tone results except for a response of 25 dB at 500 Hz on the right side. No speech recognition testing was performed. She reportedly passed school screening hearing tests in first and third grade. She was first identified with hearing loss in 2000 when she was 11 years old. An audiogram in January 2000 revealed a mild conductive hearing loss in the left ear with an excellent word recognition score (96%, Fig. 1B). Due to the newly identified hearing loss, she had two follow-up audiology evaluations later and both audiograms confirmed the conductive loss, shown in Fig. 1C. Tympanometry was normal but acoustic reflexes were absent, and middle-ear pathology was presumed. Word recognition testing was not repeated on these follow-up audiograms. In late 2000, she went to a different institution for an auditory processing evaluation because of her difficulties in learning at school. During the evaluation, the audiologist suspected a sensorineural hearing loss in the left ear based on the absence of otoacoustic emissions and poor word recognition score on the left. However, an electrophysiological (auditory brainstem response) test was interpreted as a conductive hearing loss without indication of retrocochlear disease. She was referred to an
* Corresponding author at: Department of Otolaryngology and Communication Enhancement, 300 Longwood Ave., LO-367, Boston, MA 02115, United States. Tel.: +1 617 355 6469; fax: +1 617 730 0320. E-mail address: [email protected] (G. Zhou). 1871-4048/$ – see front matter ß 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.pedex.2009.10.004
M. Neault et al. / International Journal of Pediatric Otorhinolaryngology Extra 5 (2010) 186–189
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Fig. 1. Serial audiograms showed the progression of her hearing loss over time. In audiogram C, D, E and F, hearing thresholds are shown for the left ear only. Audiogram G was done after the tumor removal, only normal hearing in the right ear shown here and no hearing in the left ear. WRS: word recognition score; CNT: could not test. DNT: did not test.
otolaryngologist and had an imaging study (MRI with contrast). The MRI showed gadolinium enhancement in the basal turn of the left cochlea, suggesting either inflammatory disease or schwannoma. Follow-up and hearing re-evaluation in 6–12 months were recommended. In 2001, after her follow-up audiologic evaluation showed a mixed hearing loss with a poor word recognition score in the left ear (shown in Fig. 1D), she was referred to our Otolaryngology Department and the hearing loss was verified, seen in Fig. 1E. Auditory brainstem response testing showed no identifiable waves (only small cochlear microphonics) on left ear stimulation, and otoacoustic emissions were absent in the left ear. After reviewing her MRI and consultation with our neuroradiologist, an intracochlear schwannoma was diagnosed. The patient did not have a family history of neurofibromatosis type II (NF2), and a genetics consultation did not find any signs of NF2 in the patient or either parent. The diagnosis and potential treatment of ICS was discussed with the patient and her parents. To address her listening difficulties, FM system installation in her classroom was recommended. Given that she had no other symptoms, such as vertigo and facial weakness, and she already had poor speech recognition, it was decided to watch her cautiously with close monitoring by audiogram and MRI exam. The decision was well understood and appreciated by the patient and her family. She had several subsequent MRI’s with the October 2003 study showing growth of the schwannoma, then involving the basal, middle and part of the apical turn of the left cochlea, seen in Figs. 2 and 3. The tumor was still limited to the cochlea and the internal auditory canal was not involved, shown by the CT scan (Fig. 4). In addition, her hearing loss in the left ear progressed to a profound loss, seen in Fig. 1F. In order to prevent the tumor from growing into the internal auditory canal, which may cause vestibular and/or facial complications, excision of the ICS was recommended and she was referred to a neurotologist. The surgery was uneventful and successful. A post-auricular canal wall up mastoidectomy with facial recess approach was used for exposure of the cochlea. It was opened widely while preserving the facial nerve within the fallopian canal. The stapes was removed and replaced. The ICS was found filling nearly the entire cochlea, except for the periapex, and it was removed in its entirety. It did not extend into the vestibule or the internal auditory canal (IAC), but the lateral termination of the IAC into the modiolus was
dehiscent without cerebrospinal fluid leakage. The tumor was completely removed without any complication, including facial weakness, disequilibrium, or cerebrospinal fluid leak. Pathology was consistent with a schwannoma (Fig. 5). Post-operative followups were conducted annually, including MRI, and no recurrence of ICS has been observed. Latest audiogram continues to show normal hearing in the right ear and no hearing in the left ear. 3. Discussion Before the modern medical imaging (MRI with gadolinium contrast) era, diagnosis of ICS was typically made during autopsy or during surgery involving in the inner ear [2,5,11]. A number of isolated ICS case studies have been reported in the literature but all the patients were adults [1,8,12]. In 2007, Grayeli et al. reported a series study in 19 patients aged 25–71, with a mean age of 54 years old at diagnosis of ICS [5]. Among them, 11% had severe hearing loss and 89% had profound hearing loss in the ear with ICS. Other symptoms included tinnitus, dizziness and facial weakness. They also found the diagnosis of ICS was delayed 11 years on average. In the pediatric population, hearing loss attributable to cochlear or vestibular nerve tumors can be found in children with neurofibromatosis (type I or type II), and very rarely as sporadic vestibular schwannomas. In 1992, Chen reported 16 pediatric cases of acoustic nerve schwannoma, age 1–14 years, but none were described as intracochlear [13]. Mazzoni et al. in 2007 reported 10 cases of sporadic (non-NF2) acoustic neuroma in pediatric patients, in which the largest tumor (60 mm in diameter) was found in the youngest child at age of 12 years [14]. Most recently, Laury in 2009 reported a 13-year-old patient with unilateral neural loss due to vestibular schwannoma in the internal auditory canal [15]. The findings of ICS in our patient at the age of 13 make her the youngest patient reported with ICS. Hearing loss due to ICS is usually sensorineural and may worsen over time [8]. The initial finding of a mild conductive hearing loss in the ear with ICS in our patient was extremely unusual and presented challenges in making the diagnosis. The conductive loss might have been the result of compromise of the inner ear fluid mechanics due to the schwannoma that originated in the basal turn. Possible sensorineural involvement could be suspected with an absent acoustic reflex in the face of a normal tympanogram but
188
M. Neault et al. / International Journal of Pediatric Otorhinolaryngology Extra 5 (2010) 186–189
Fig. 4. Computer Tomography (CT) image (axial view) of the patient’s temporal bone. No enlargement of internal auditory canal (IAC) noted on either side.
Fig. 2. Magnetic Resonance Imaging (MRI) images (axial view) of the patient’s intracochlear schwannoma. In image A, an attenuation of fluid signal within the left cochlea noted on FIESTA sequences, indicated by arrow, suggesting an occupying lesion. The schwannoma, pointed by arrow, can be best seen in image B (postgadolinium contrast).
Fig. 5. Histomicrograph of the tumor shows a solid cellular lesion composed of spindle shaped cells with areas of nuclear palisading (Antoni A areas) characteristic for schwannoma.
Fig. 3. Magnetic Resonance Imaging (MRI) image (coronal view) of the tumor, indicated by arrow.
it is a nonspecific finding. Learning problems in school prompted more detailed auditory processing testing that revealed deterioration in the word recognition score. ABR was negative for retrocochlear pathology and that could be consistent with either a conductive loss or cochlear sensorineural loss. Abnormal OAEs could be similarly absent in either condition. It was ultimately careful observation of the patient over time that demonstrated a progressive mixed loss which, in turn, prompted the MR imaging that was instrumental in revealing the diagnosis. Her hearing loss rapidly progressed to a severe mixed loss, with poor word recognition ability, and then to a profound loss in less than 4 years. This progression directly correlated to the growth of the schwannoma within the cochlea; however, it is debatable whether an early excision would have saved her hearing. The decision to remove the ICS was justified to prevent it from growing into the internal auditory canal and causing vestibular and facial complications, given that her hearing was no longer useable.
Stereotactic radiosurgery is another option for treatment of a growing ICS, particularly in an attempt to spare hearing for as long as possible. However, the unresolved issues of uncertain longterm results and possible sequelae in a pediatric case make stereotactic radiosurgery less attractive than it would be in an adult case. To summarize our case, ICS is a rare diagnosis in the pediatric population. Although early diagnosis of ICS is difficult, audiologic evaluation is critical in the initial evaluation and to guide subsequent work-up. Furthermore, close follow-up of ICS is important to determine the best option for medical management. As presented here, complete excision of ICS without major complications, such as facial paralysis and disabling vertigo, is a viable and long-term option. Acknowledgment The authors thank Dr. Caroline Robson for her reading patient’s imaging studies. References [1] M.C. Gersdorff, M. Decat, T. Duprez, N. Deggouj, Intracochlear schwannoma, Eur. Arch. Otorhinolaryngol. 253 (1996) 374–376. [2] L.G. Johnsson, T.C. Kingsley, Asymptomatic intracochlear neurinoma. A temporal bone report, Arch. Otolaryngol. 107 (1981) 377–381. [3] M.J. Donnelly, C.A. Daly, R.J. Briggs, MR imaging features of an intracochlear acoustic schwannoma, J. Laryngol. Otol. 108 (1994) 1111–1114.
M. Neault et al. / International Journal of Pediatric Otorhinolaryngology Extra 5 (2010) 186–189 [4] I. Grande-Nagel, T.E. Mayer, W. Heide, D. Kompf, H.D. Weiss, MR tomographic and clinical course of intracochlear acoustic neurinoma, Rofo 167 (1997) 430–432. [5] A.B. Grayeli, C. Fond, M. Kalamarides, D. Bouccara, D. Cazals-Hatem, F. Cyna-Gorse, et al., Diagnosis and management of intracochlear schwannomas, Otol. Neurotol. 28 (2007) 951–957. [6] J.D. Green Jr., J.D. McKenzie, Diagnosis and management of intralabyrinthine schwannomas, Laryngoscope 109 (1999) 1626–1631. [7] R.J. Kennedy, C. Shelton, K.L. Salzman, H.C. Davidson, H.R. Harnberger, Intralabyrinthine schwannomas: diagnosis, management, and a new classification system, Otol. Neurotol. 25 (2004) 160–167. [8] T. Nishimura, H. Hosoi, Progressive hearing loss in intracochlear schwannoma, Eur. Arch. Otorhinolaryngol. 265 (2008) 489–492. [9] J.W. Casselman, Diagnostic imaging in clinical neuro-otology, Curr. Opin. Neurol. 15 (2002) 23–30.
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[10] J.L. Hegarty, S. Patel, N. Fischbein, R.K. Jackler, A.K. Lalwani, The value of enhanced magnetic resonance imaging in the evaluation of endocochlear disease, Laryngoscope 112 (2002) 8–17. [11] I. Ohtani, C. Suzuki, T. Aikawa, Temporal bone pathology in intracochlear schwannoma with profound hearing loss, Auris Nasus Larynx 17 (1990) 17–22. [12] S. Knipping, A. Fabricius, S. Kosling, M. Bloching, Intracochlear schwannoma as a cause of a deafness: a case report, Hno 55 (2007) 641–643. [13] T.C. Chen, D.R. Maceri, S.L. Giannotta, L. Shih, J.G. McComb, Unilateral acoustic neuromas in childhood without evidence of neurofibromatosis: case report and review of the literature, Am. J. Otol. 13 (1992) 318–322. [14] A. Mazzoni, S.P. Dubey, A.M. Poletti, G. Colombo, Sporadic acoustic neuroma in pediatric patients, Int. J. Pediatr. Otorhinolaryngol. 71 (2007) 1569–1572. [15] A.M. Laury, S. Casey, S. McKay, J.A. Germiller, Etiology of unilateral neural hearing loss in children, Int. J. Pediatr. Otorhinolaryngol. 73 (2009) 417–427.
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology Extra journal homepage: www.elsevier.com/locate/ijporl
Case report
Atypical presentation of intracochlear schwannoma in a child Marilyn Neault a,b, Guangwei Zhou a,b,*, Margaret Kenna a,b, Dennis Poe a,b a b
Department of Otolaryngology and Communication Enhancement, Children’s Hospital Boston, United States Department of Otology and Laryngology, Harvard Medical School, United States
A R T I C L E I N F O
A B S T R A C T
Article history: Received 20 August 2009 Received in revised form 5 October 2009 Accepted 8 October 2009 Available online 7 November 2009
Intracochlear schwannoma (ICS) is a rare tumor that can cause significant hearing loss. Previous clinical reports on ICS have described this disease in adults. We present a pediatric patient with left-sided ICS who initially presented with a mild conductive hearing loss. We demonstrate the progression of the hearing loss over a span of several years through serial audiograms, as well as the process of diagnosis and treatment. This rare and unique case demonstrates that ICS can be found in young children. ß 2009 Elsevier Ireland Ltd. All rights reserved.
Keywords: Intracochlear schwannoma (ICS) Conductive hearing loss (CHL) Word recognition score (WRS)
1. Introduction
2. Case report
While vestibular schwannoma (formerly acoustic neuroma) is one of the most commonly seen benign intracranial tumors, intracochlear schwannoma (ICS) is relatively rare [1–4]. The first case of ICS was diagnosed by Nager in 1917 during an autopsy of a deaf patient [5]. Nowadays, with the improvements in contemporary medical imaging technology, the clinical diagnosis of ICS has become possible. Nonetheless, an extremely small number of ICS have been reported in the literature [5–7]. To the best of our knowledge, no ICS in a child has ever been reported. The early symptoms or complaints of ICS are often auditoryrelated, such as unilateral hearing loss and/or tinnitus [1,5,7,8]. The hearing loss is usually sensorineural, typically along with poor speech recognition ability. Additional audiologic evaluation, such as acoustic reflexes and auditory brainstem response testing, may be helpful; however, the definitive diagnosis of ICS requires Magnetic Resonance Imaging (MRI) with gadolinium contrast [3,4,6,9,10]. In this report, we present one case of ICS in a teenage girl who has an unusual history of hearing loss and an interesting process that ultimately led to a diagnosis. Our objective is to raise awareness of ICS in children and demonstrate how to appropriately diagnose and manage this rare neoplasm.
A 13-year-old girl was referred to our pediatric otolaryngology clinic for further evaluation of left-sided hearing loss. She had an uncomplicated medical history and had no complaints of tinnitus, dizziness or facial weakness. She did have a history of otitis media with effusion and underwent myringotomy with tubes at age 3 years. Results of otologic and neurologic exam in the pediatric otolaryngology outpatient clinic were unremarkable. Her earliest audiogram available was obtained in 1993 when she was 4 years old and is shown in Fig. 1A. She had normal pure tone results except for a response of 25 dB at 500 Hz on the right side. No speech recognition testing was performed. She reportedly passed school screening hearing tests in first and third grade. She was first identified with hearing loss in 2000 when she was 11 years old. An audiogram in January 2000 revealed a mild conductive hearing loss in the left ear with an excellent word recognition score (96%, Fig. 1B). Due to the newly identified hearing loss, she had two follow-up audiology evaluations later and both audiograms confirmed the conductive loss, shown in Fig. 1C. Tympanometry was normal but acoustic reflexes were absent, and middle-ear pathology was presumed. Word recognition testing was not repeated on these follow-up audiograms. In late 2000, she went to a different institution for an auditory processing evaluation because of her difficulties in learning at school. During the evaluation, the audiologist suspected a sensorineural hearing loss in the left ear based on the absence of otoacoustic emissions and poor word recognition score on the left. However, an electrophysiological (auditory brainstem response) test was interpreted as a conductive hearing loss without indication of retrocochlear disease. She was referred to an
* Corresponding author at: Department of Otolaryngology and Communication Enhancement, 300 Longwood Ave., LO-367, Boston, MA 02115, United States. Tel.: +1 617 355 6469; fax: +1 617 730 0320. E-mail address: [email protected] (G. Zhou). 1871-4048/$ – see front matter ß 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.pedex.2009.10.004
M. Neault et al. / International Journal of Pediatric Otorhinolaryngology Extra 5 (2010) 186–189
187
Fig. 1. Serial audiograms showed the progression of her hearing loss over time. In audiogram C, D, E and F, hearing thresholds are shown for the left ear only. Audiogram G was done after the tumor removal, only normal hearing in the right ear shown here and no hearing in the left ear. WRS: word recognition score; CNT: could not test. DNT: did not test.
otolaryngologist and had an imaging study (MRI with contrast). The MRI showed gadolinium enhancement in the basal turn of the left cochlea, suggesting either inflammatory disease or schwannoma. Follow-up and hearing re-evaluation in 6–12 months were recommended. In 2001, after her follow-up audiologic evaluation showed a mixed hearing loss with a poor word recognition score in the left ear (shown in Fig. 1D), she was referred to our Otolaryngology Department and the hearing loss was verified, seen in Fig. 1E. Auditory brainstem response testing showed no identifiable waves (only small cochlear microphonics) on left ear stimulation, and otoacoustic emissions were absent in the left ear. After reviewing her MRI and consultation with our neuroradiologist, an intracochlear schwannoma was diagnosed. The patient did not have a family history of neurofibromatosis type II (NF2), and a genetics consultation did not find any signs of NF2 in the patient or either parent. The diagnosis and potential treatment of ICS was discussed with the patient and her parents. To address her listening difficulties, FM system installation in her classroom was recommended. Given that she had no other symptoms, such as vertigo and facial weakness, and she already had poor speech recognition, it was decided to watch her cautiously with close monitoring by audiogram and MRI exam. The decision was well understood and appreciated by the patient and her family. She had several subsequent MRI’s with the October 2003 study showing growth of the schwannoma, then involving the basal, middle and part of the apical turn of the left cochlea, seen in Figs. 2 and 3. The tumor was still limited to the cochlea and the internal auditory canal was not involved, shown by the CT scan (Fig. 4). In addition, her hearing loss in the left ear progressed to a profound loss, seen in Fig. 1F. In order to prevent the tumor from growing into the internal auditory canal, which may cause vestibular and/or facial complications, excision of the ICS was recommended and she was referred to a neurotologist. The surgery was uneventful and successful. A post-auricular canal wall up mastoidectomy with facial recess approach was used for exposure of the cochlea. It was opened widely while preserving the facial nerve within the fallopian canal. The stapes was removed and replaced. The ICS was found filling nearly the entire cochlea, except for the periapex, and it was removed in its entirety. It did not extend into the vestibule or the internal auditory canal (IAC), but the lateral termination of the IAC into the modiolus was
dehiscent without cerebrospinal fluid leakage. The tumor was completely removed without any complication, including facial weakness, disequilibrium, or cerebrospinal fluid leak. Pathology was consistent with a schwannoma (Fig. 5). Post-operative followups were conducted annually, including MRI, and no recurrence of ICS has been observed. Latest audiogram continues to show normal hearing in the right ear and no hearing in the left ear. 3. Discussion Before the modern medical imaging (MRI with gadolinium contrast) era, diagnosis of ICS was typically made during autopsy or during surgery involving in the inner ear [2,5,11]. A number of isolated ICS case studies have been reported in the literature but all the patients were adults [1,8,12]. In 2007, Grayeli et al. reported a series study in 19 patients aged 25–71, with a mean age of 54 years old at diagnosis of ICS [5]. Among them, 11% had severe hearing loss and 89% had profound hearing loss in the ear with ICS. Other symptoms included tinnitus, dizziness and facial weakness. They also found the diagnosis of ICS was delayed 11 years on average. In the pediatric population, hearing loss attributable to cochlear or vestibular nerve tumors can be found in children with neurofibromatosis (type I or type II), and very rarely as sporadic vestibular schwannomas. In 1992, Chen reported 16 pediatric cases of acoustic nerve schwannoma, age 1–14 years, but none were described as intracochlear [13]. Mazzoni et al. in 2007 reported 10 cases of sporadic (non-NF2) acoustic neuroma in pediatric patients, in which the largest tumor (60 mm in diameter) was found in the youngest child at age of 12 years [14]. Most recently, Laury in 2009 reported a 13-year-old patient with unilateral neural loss due to vestibular schwannoma in the internal auditory canal [15]. The findings of ICS in our patient at the age of 13 make her the youngest patient reported with ICS. Hearing loss due to ICS is usually sensorineural and may worsen over time [8]. The initial finding of a mild conductive hearing loss in the ear with ICS in our patient was extremely unusual and presented challenges in making the diagnosis. The conductive loss might have been the result of compromise of the inner ear fluid mechanics due to the schwannoma that originated in the basal turn. Possible sensorineural involvement could be suspected with an absent acoustic reflex in the face of a normal tympanogram but
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M. Neault et al. / International Journal of Pediatric Otorhinolaryngology Extra 5 (2010) 186–189
Fig. 4. Computer Tomography (CT) image (axial view) of the patient’s temporal bone. No enlargement of internal auditory canal (IAC) noted on either side.
Fig. 2. Magnetic Resonance Imaging (MRI) images (axial view) of the patient’s intracochlear schwannoma. In image A, an attenuation of fluid signal within the left cochlea noted on FIESTA sequences, indicated by arrow, suggesting an occupying lesion. The schwannoma, pointed by arrow, can be best seen in image B (postgadolinium contrast).
Fig. 5. Histomicrograph of the tumor shows a solid cellular lesion composed of spindle shaped cells with areas of nuclear palisading (Antoni A areas) characteristic for schwannoma.
Fig. 3. Magnetic Resonance Imaging (MRI) image (coronal view) of the tumor, indicated by arrow.
it is a nonspecific finding. Learning problems in school prompted more detailed auditory processing testing that revealed deterioration in the word recognition score. ABR was negative for retrocochlear pathology and that could be consistent with either a conductive loss or cochlear sensorineural loss. Abnormal OAEs could be similarly absent in either condition. It was ultimately careful observation of the patient over time that demonstrated a progressive mixed loss which, in turn, prompted the MR imaging that was instrumental in revealing the diagnosis. Her hearing loss rapidly progressed to a severe mixed loss, with poor word recognition ability, and then to a profound loss in less than 4 years. This progression directly correlated to the growth of the schwannoma within the cochlea; however, it is debatable whether an early excision would have saved her hearing. The decision to remove the ICS was justified to prevent it from growing into the internal auditory canal and causing vestibular and facial complications, given that her hearing was no longer useable.
Stereotactic radiosurgery is another option for treatment of a growing ICS, particularly in an attempt to spare hearing for as long as possible. However, the unresolved issues of uncertain longterm results and possible sequelae in a pediatric case make stereotactic radiosurgery less attractive than it would be in an adult case. To summarize our case, ICS is a rare diagnosis in the pediatric population. Although early diagnosis of ICS is difficult, audiologic evaluation is critical in the initial evaluation and to guide subsequent work-up. Furthermore, close follow-up of ICS is important to determine the best option for medical management. As presented here, complete excision of ICS without major complications, such as facial paralysis and disabling vertigo, is a viable and long-term option. Acknowledgment The authors thank Dr. Caroline Robson for her reading patient’s imaging studies. References [1] M.C. Gersdorff, M. Decat, T. Duprez, N. Deggouj, Intracochlear schwannoma, Eur. Arch. Otorhinolaryngol. 253 (1996) 374–376. [2] L.G. Johnsson, T.C. Kingsley, Asymptomatic intracochlear neurinoma. A temporal bone report, Arch. Otolaryngol. 107 (1981) 377–381. [3] M.J. Donnelly, C.A. Daly, R.J. Briggs, MR imaging features of an intracochlear acoustic schwannoma, J. Laryngol. Otol. 108 (1994) 1111–1114.
M. Neault et al. / International Journal of Pediatric Otorhinolaryngology Extra 5 (2010) 186–189 [4] I. Grande-Nagel, T.E. Mayer, W. Heide, D. Kompf, H.D. Weiss, MR tomographic and clinical course of intracochlear acoustic neurinoma, Rofo 167 (1997) 430–432. [5] A.B. Grayeli, C. Fond, M. Kalamarides, D. Bouccara, D. Cazals-Hatem, F. Cyna-Gorse, et al., Diagnosis and management of intracochlear schwannomas, Otol. Neurotol. 28 (2007) 951–957. [6] J.D. Green Jr., J.D. McKenzie, Diagnosis and management of intralabyrinthine schwannomas, Laryngoscope 109 (1999) 1626–1631. [7] R.J. Kennedy, C. Shelton, K.L. Salzman, H.C. Davidson, H.R. Harnberger, Intralabyrinthine schwannomas: diagnosis, management, and a new classification system, Otol. Neurotol. 25 (2004) 160–167. [8] T. Nishimura, H. Hosoi, Progressive hearing loss in intracochlear schwannoma, Eur. Arch. Otorhinolaryngol. 265 (2008) 489–492. [9] J.W. Casselman, Diagnostic imaging in clinical neuro-otology, Curr. Opin. Neurol. 15 (2002) 23–30.
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[10] J.L. Hegarty, S. Patel, N. Fischbein, R.K. Jackler, A.K. Lalwani, The value of enhanced magnetic resonance imaging in the evaluation of endocochlear disease, Laryngoscope 112 (2002) 8–17. [11] I. Ohtani, C. Suzuki, T. Aikawa, Temporal bone pathology in intracochlear schwannoma with profound hearing loss, Auris Nasus Larynx 17 (1990) 17–22. [12] S. Knipping, A. Fabricius, S. Kosling, M. Bloching, Intracochlear schwannoma as a cause of a deafness: a case report, Hno 55 (2007) 641–643. [13] T.C. Chen, D.R. Maceri, S.L. Giannotta, L. Shih, J.G. McComb, Unilateral acoustic neuromas in childhood without evidence of neurofibromatosis: case report and review of the literature, Am. J. Otol. 13 (1992) 318–322. [14] A. Mazzoni, S.P. Dubey, A.M. Poletti, G. Colombo, Sporadic acoustic neuroma in pediatric patients, Int. J. Pediatr. Otorhinolaryngol. 71 (2007) 1569–1572. [15] A.M. Laury, S. Casey, S. McKay, J.A. Germiller, Etiology of unilateral neural hearing loss in children, Int. J. Pediatr. Otorhinolaryngol. 73 (2009) 417–427.