Interest of computer tomography in the study of prognostic factors of otosclerosis.

BACKGROUND: Otosclerosis is a primary osteodystrophy of the otic capsule that causes stapedo-vestibular ankylosis. Its diagnosis is suspected on the basis of clinical and audiometric elements, basically in the presence of conductive hearing loss with a normal eardrum. The CT-scan is an essential examination for the preoperative evaluation of otosclerosis. The aim of our study was to evaluate the use of CT-scanning in predicting the functional outcome of otosclerosis surgery by correlating postoperative audiometric results and preoperative CT findings. METHODS: We conducted a retrospective study at the ENT Department in association with the Medical Imaging Department of our hospital, over a period of 8 years, from January 2014 to December 2022 and involving 90 patients (104 ears). RESULTS: The average age of our patients was 40 years with extremes ranging from 22 to 61 years. We noted a sex ratio of 0.38. The preoperative CT-scan showed signs of otosclerosis in 87% of the cases and infra-radiological forms in 13% of the cases. Veillon stage II was the most frequent radiological stage encountered with a percentage of 48%. A good audiometric evolution, defined by a closure of postoperative Air Bone Gap (ABG ≤ 20 dB) and by an improvement of Bone Conduction (BC gain ≥ 0), was recorded in 86 cases (82.7%) for ABG and in 84 cases (80.8%) for BC gain. Scanographic predictive factors of poor postoperative outcome for ABG and BC gain were: advanced stages (Veillon stage III and IV), endosteal effraction, and round window involvement. According to multivariate analysis, only the extent of otosclerotic foci was directly and independently associated with the postoperative audiometric outcome. CONCLUSION: The CT-scan is an essential examination in the preoperative evaluation of otosclerosis. It allows a positive diagnosis to be made and evaluate the extension of otosclerosis. Moreover, thanks to the analysis of the extent of the otosclerosis foci, mainly by the Veillon classification, the CT-scan allows to predict the postoperative audiometric prognosis.

Conductive Hearing Loss in Children.

A variety of congenital and acquired disorders result in pediatric conductive hearing loss. Malformations of the external auditory canal are invariably associated with malformations of the middle ear space and ossicles. Isolated ossicular malformations are uncommon. Syndromes associated with external and middle ear malformations are frequently associated with abnormal development of first and second pharyngeal arch derivatives. Chronic inflammatory disorders include cholesteatoma, cholesterol granuloma, and tympanosclerosis.

Absent pyramidal eminence and stapedial tendon associated with congenital stapes footplate fixation: Intraoperative and radiographic findings.

OBJECTIVE: Report an association between congenital stapes footplate fixation (CSFF) and radiological absence of the pyramidal eminence and stapedial tendon. PATIENTS: Children and adults with intraoperatively confirmed CSFF and an absent stapedial tendon. INTERVENTIONS: Computed tomography (CT); exploratory tympanotomy with stapedotomy. MAIN OUTCOME MEASURES: Absence of a pyramidal eminence and stapedial tendon aperture identified on preoperative CT that was confirmed intraoperatively. RESULTS: Eight patients with intraoperative confirmation of CSFF and absent stapedial tendon were retrospectively identified. The average preoperative bone conduction and air conduction pure tone averages were 19.6 dB (SD 15.6 dB) and 55.9 dB (SD 23.6 dB), respectively. The average air-bone gap was 36.3 dB (SD 17.9 dB) preoperatively. In the seven patients who underwent preoperative CT, all were consistently identified to have an absent or hypoplastic pyramidal eminence and absent stapedial tendon aperture at the pyramidal eminence. In six cases, the stapedial footplate appeared normal, while in one case the footplate appeared abnormal which correlated with severe facial nerve prolapse observed intraoperatively. All eight cases underwent exploratory tympanotomy and demonstrated intraoperative stapes footplate fixation, absent stapedial tendon and either absent or hypoplastic pyramidal eminence, which correlated with preoperative CT findings. CONCLUSIONS: This study identifies a clinically pragmatic association between an absent pyramidal eminence identified on high-resolution CT and the diagnosis of CSFF. In a condition that otherwise generally lacks distinctive radiological features, the absence of a pyramidal eminence on CT in a patient with nonprogressive, congenital conductive hearing loss may strengthen clinical suspicion for CSFF.

Isolated Incudostapedial Cholesteatomas: Unique Radiologic and Surgical Features.

OBJECTIVES: Congenital cholesteatomas originate from epithelial tissue present within the middle ear in patients with an intact tympanic membrane, no history of otologic surgery, otorrhea, or tympanic membrane perforation. They are diagnosed by a pearl-like lesion on otoscopy and computed tomography (CT) scan showing an expansile soft-tissue mass. We describe a series of patients with no prior otologic history presenting with progressive unilateral conductive hearing loss and normal otoscopy. The CT scans showed ossicular erosion without obvious soft-tissue mass. Surgery confirmed incudostapedial erosion found to be cholesteatoma. In this study, we characterize the clinical course of patients diagnosed with isolated incudostapedial cholesteatoma (IIC) and review possible pathologic mechanisms. METHODS: Retrospective review of IIC cases treated by the Department of Pediatric Otolaryngology, Rady Children's Hospital, San Diego, 2014 to 2020. Data included patient demographics, clinical features, imaging, surgical findings, and audiologic data. RESULTS: Five patients were diagnosed with IIC (3 [60%] female; mean age at presentation 10.7 years [range 5.5-16.0]). All patients presented with postlingual unilateral conductive hearing loss and normal otoscopy without any past otologic history; delay in diagnosis ranged from 4 months to several years. The CT scans showed ossicular chain erosion with an absent long process of the incus and/or stapes superstructure. All patients underwent middle ear exploration, revealing a thin layer of cholesteatoma in the incudostapedial region, confirmed by histopathology. Mean preoperative speech reception threshold was 55 dB and improved to a mean of 31 dB in the 4 patients who underwent ossicular chain reconstruction. CONCLUSION: Isolated incudostapedial cholesteatoma should be included as a possible etiology in pediatric patients with insidious onset of unilateral conductive hearing loss with normal otoscopy, unremarkable otologic history, and a CT scan showing ossicular abnormality/disruption without notable middle ear mass. These patients should be counseled preoperatively regarding the possibility of cholesteatoma and should undergo middle ear exploration with possible ossiculoplasty.

High Resolution Computed Tomography (HRCT) Imaging Findings of Oval Window Atresia with Surgical Correlation.

INTRODUCTION: Isolated oval window atresia (OWA) is a rare cause of congenital conductive middle ear deafness and may be overlooked owing to the normal appearance of the external ear. This anomaly has been previously described, although the published numbers with both imaging and surgical findings are few. Our aim is to correlate the imaging features of OWA with intraoperative findings. MATERIALS AND METHODS: This is a single-centre retrospective evaluation of patients who were diagnosed with OWA and who received surgery from January 1999 to July 2006. No new case was diagnosed after 2006 to the time of preparation of this manuscript. High resolution computed tomography (HRCT) imaging of the temporal bones of the patients were retrospectively evaluated by 2 head and neck radiologists. Images were evaluated for the absence of the oval window, ossicular chain abnormalities, position of the facial nerve canal, and other malformations. Imaging findings were then correlated with surgical findings. RESULTS: A total of 9 ears in 7 patients (two of whom with bilateral lesions) had surgery for OWA. All patients had concomitant findings of absent stapes footplate with normal, deformed or absent stapes superstructure and an inferiorly displaced facial nerve canal. HRCT was sensitive in identifying OWA and associated ossicular chain and facial nerve abnormalities, which were documented surgically. CONCLUSION: OWA is a rare entity that can be diagnosed with certainty on HRCT, best visualised on coronal plane. Imaging findings of associated middle ear abnormalities, position of the facial nerve canal, which is invariably mal-positioned, and associated deformity of the incus are important for presurgical planning and consent.

New Imaging Findings of Incomplete Partition Type III Inner Ear Malformation and Literature Review.

Incomplete partition type III, also referred to as X-linked deafness, is a rare genetic inner ear malformation. Its characteristic CT findings, including bulbous dilation of the internal auditory canal and absence of the modiolus with the interscalar septa present, have been well-recognized. In this series of 19 cases, we report the abnormalities of the vestibule and semicircular canals and provide a comprehensive description of their CT and MR imaging findings. The inner ear malformations in incomplete partition type III were bilateral and basically symmetric, with involvement of the internal auditory canal, nerve canals in the fundus, cochlea, vestibule, semicircular canals, vestibular aqueduct, otic capsule, round window, oval window, and stapes. An irregular vestibule with a cystic appearance is also a distinctive imaging feature, which could be seen in about 90% of our patients, with a cystic appearance of the semicircular canals present in nearly half of the cases.

Isolated malleus fixation: A pediatric case series.

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 post-operative 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.

Conductive hearing loss with a "dry middle ear cleft"-A comprehensive pictorial review with CT.

Conductive hearing loss (CHL) commonly results from middle ear fluid and inflammation (otitis media). Less commonly in patients with CHL, the middle ear cleft is well aerated or 'dry' with absence of soft tissue or fluid clinically and on imaging. There are numerous causes for this but they can be clinically challenging to diagnose. This pictorial review aims to illustrate and discuss the CT features of both common and less common causes of CHL in patients with a "dry middle ear cavity".

Association of Hearing Loss and Otologic Outcomes With Fibrous Dysplasia.

Importance: Fibrous dysplasia (FD) and McCune-Albright syndrome (MAS) are rare bone and endocrine disorders in which expansile fibro-osseous lesions result in deformity, pain, and functional impairment. The effect of FD on hearing and otologic function has not been established. Objectives: To characterize audiologic and otologic manifestations in a large cohort of individuals with FD/MAS and to investigate potential mechanisms of hearing loss. Design, Setting, and Participants: In this natural history study, individuals with craniofacial FD seen at a clinical research center underwent clinical, biochemical, computed tomographic, audiologic, and otolaryngologic evaluations. Main Outcomes and Measures: Clinical and radiologic features associated with hearing loss and otologic disease were evaluated. Conductive hearing loss was hypothesized to be associated with narrowing of the external auditory canal (EAC), FD involving the epitympanum, and FD crowding the ossicular chain. Sensorineural hearing loss was hypothesized to be associated with FD affecting the internal auditory canal (IAC) and otic capsule. Results: Of the 130 study participants with craniofacial FD who were evaluated, 116 (89.2%) had FD that involved the temporal bone (median age, 19.6 years; range, 4.6-80.3 years; 64 female [55.2%]), whereas 14 (10.8%) had craniofacial FD that did not involve the temporal bone. Of the 183 ears with temporal bone FD, hearing loss was identified in 41 ears (22.4%) and was conductive in 27 (65.9%), sensorineural in 12 (29.3%), and mixed in 2 (4.9%). Hearing loss was mild and nonprogressive in most participants. Whereas EACs were narrower in ears with FD (mean difference [MD], 0.33 mm; 95% CI, 0.11-0.55 mm), this finding was associated with conductive hearing loss in only 4 participants. Fibrous dysplasia crowding of the ossicles was associated with conductive hearing loss (odds ratio [OR], 5.0; 95% CI, 2.1-11.6). The IAC length was not different between ears with and without FD (MD, -0.37; 95% CI, -0.95 to 0.211); however, canals were elongated in ears with sensorineural hearing loss (MD, -1.33; 95% CI, -2.60 to -0.07). Otic capsule involvement was noted in only 4 participants, 2 of whom had sensorineural hearing loss. Both MAS-associated growth hormone excess (OR, 3.1; 95% CI, 1.3-7.5) and neonatal hypercortisolism (OR, 11; 95% CI, 2.5-55) were associated with an increased risk of hearing loss . Conclusions and Relevance: Hearing loss in craniofacial FD is common and mild to moderate in most individuals. It typically arises from FD crowding of the ossicular chain and elongation of the IAC, whereas EAC stenosis and otic capsule invasion are less common causes. Individuals with craniofacial FD should undergo otolaryngologic evaluation and monitoring, including assessment to identify those with high-risk features.

Vascular mapping of the retroauricular skin - proposal for a posterior superior surgical incision for transcutaneous bone-conduction hearing implants.

BACKGROUND: Passive transcutaneous osseointegrated hearing implant systems have become increasingly popular more recently. The area over the implant is vulnerable due to vibration and pressure from the externally worn sound processor. Good perfusion and neural integrity has the potential to reduce complications. The authors' objective was to determine the ideal surgical exposure to maintain perfusion and neural integrity and decrease surgical time as a result of reduced bleeding. METHODS: The vascular anatomy of the temporal-parietal soft tissue was examined in a total of 50 subjects. Imaging diagnostics included magnetic resonance angiography in 12 and Doppler ultrasound in 25 healthy subjects to reveal the arterial network. Cadaver dissection of 13 subjects formed the control group. The prevalence of the arteries were statistically analyzed with sector analysis in the surgically relevant area. RESULTS: The main arterial branches of this region could be well identified with each method. Statistical analysis showed that the arterial pattern was similar in all subjects. The prevalence of major arteries is low in the upper posterior area though large in proximity to the auricle region. CONCLUSIONS: Diverse methods indicate the advantages of a posterior superior incision because the major arteries and nerves are at less risk of damage and best preserved. Although injury to these structures is rare, when it occurs, the distal flow is compromised and the peri-implant area is left intact. Hand-held Doppler is efficient and cost-effective in finding the best position for incision, if necessary, in subjects with a history of surgical stress to the retroauricular skin. TRIAL REGISTRATION: This was a non-interventional study.

A clinical experience of 'STAMP' plate-guided Bonebridge implantation.

CONCLUSION: The surface template-assisted marker positioning (STAMP) method is useful for successful Bonebridge™ (BB) implantation on a planned site while avoiding dangerous positions. OBJECTIVES: To confirm the usefulness of the STAMP method for the safe operation of BB. METHODS: From a patient's temporal bone CT data, a guide plate and confirmation plate were generated by the STAMP method. The guide plate is used to mark the correct place for implantation, while the confirmation plate lets us know the correct angle and depth of the hole. RESULTS: With the guide plate, the correct place for BB implantation was easily found. The hole was made to be an appropriate size with the confirmation plate while exposing only a small part of sigmoid sinus as simulated. Finally, the BB implant was successfully placed exactly at the planned site.

Temporal bone changes in patients with Goldenhar syndrome with special emphasis on inner ear abnormalities.

OBJECTIVE: Goldenhar syndrome is a developmental disorder presenting with orofacial and vertebral anomalies, which are also accompanied by abnormalities in other organs. We examined temporal bone changes with special emphasis on inner ear abnormalities in these patients. STUDY DESIGN: A retrospective review of 7 new cases in addition to a previously published series of 14 cases with clinically diagnosed Goldenhar syndrome was carried out to search for inner ear anomalies. In addition, temporal bone imaging studies from the literature were summarized and compared with our results. SETTING: Departments of Neuroradiology and Otorhinolaryngology at a university hospital. PATIENTS: In addition to the previous series of 14 patients, 7 new patients with Goldenhar syndrome were identified. INTERVENTIONS: Patients underwent otologic examination, audiometric studies, and high-resolution computed tomography (CT) or magnetic resonance imaging (MRI) of the temporal bone. MAIN OUTCOME MEASURE: Temporal bone changes and specifically inner ear malformations. RESULTS: Nineteen of 21 patients showed changes of the external and middle ear correlating with the literature. Seven of 21 patients showed inner ear abnormalities constituting one-third of all patients. These ranged from mild such as vestibular enlargement to severe defects such as cochlear hypoplasia and common cavity. CONCLUSION: Inner ear abnormalities were present in one-third of patients. Although in some cases, these might not be of clinical significance, some patients show severe defects of the inner ear requiring more complex hearing loss therapy. Therefore, imaging of the temporal bone structures is important in the care of these patients.

The prevalence of superior semicircular canal dehiscence in conductive and mixed hearing loss in the absence of other pathology using submillimetric temporal bone computed tomography.

OBJECTIVE: The objective of this study was to assess the relationship between superior semicircular canal dehiscence (SSCD) and hearing impairment. METHODS: We retrospectively compared the prevalence of SSCD in the ears classified as conductive hearing loss (CHL), mixed hearing loss (MHL), and normal hearing status using submillimetric temporal bone computed tomography (TBCT) on the basis of coronal and additional reformatted planes dedicated to SSCD. RESULTS: From the patients with CHL (n = 127) and MHL (n = 45), the overall prevalence of SSCD in the ears classified as CHL, MHL, and normal hearing status were 6.6%, 7.2%, and 3.0%, respectively. Furthermore, the odds ratio for SSCD in the absence of any cause of hearing loss (eg, dysfunction of the tympanic membrane or middle ear, TBCT abnormalities, otosclerosis, trauma, surgery) was 5.35 in MHL (4/27; P = 0.037, 95% confidence interval, 1.1-25.81) and 3.31 in CHL (5/61; P = 0.115, 95% confidence interval, 0.75-14.63), compared with normal hearing status. CONCLUSIONS: Bony covering of the SSC should be specifically evaluated in patients with hearing impairment using submillimetric TBCT.

Superior canal dehiscence syndrome: clinical manifestations and radiologic correlations.

The objective of this study is to describe the superior canal dehiscence syndrome (SCDS) and its vestibule-cochlear manifestations, while analyzing dehiscence size, audiogram and vestibular-evoked myogenic potential (VEMP) changes following dehiscence obliteration. We conducted a prospective study in a tertiary referral center. All Patients diagnosed and surgically treated for SCDS were operated through a middle fossa craniotomy (MFC). Clinical and radiological data were collected. The main outcome measures were Air-bone gaps, Pure-tone average (PTA), speech discrimination scores (SDS) and VEMP thresholds and were correlated to dehiscence size. 28 patients were included in this study with a mean dehiscence size of 4.68 mm. Phonophobia and imbalance were the most debilitating cochlear and vestibular symptoms, respectively. At 2 months postoperatively, low-frequency air-bone gaps showed a statistically significant improvement (p < 0.001). SDS and PTA did not show any statistically significant changes 2 months postoperatively (p = 0.282 and p = 0.295, respectively). VEMP threshold differences between operated and contralateral ears were statistically significant preoperatively (p < 0.001) and non-significant 2 months postoperatively (p = 0.173). Dehiscence size only showed a statistically significant correlation with preoperative total cochlear symptoms, while remaining insignificant with all other variables measured. Air-bone gaps, VEMP and computerized tomography remain essential tools in diagnosing and following SCDS. Dehiscence size is an independent factor in the analysis of SCDS, with cochlear symptomatology being associated to dehiscence sizes. Finally, it is shown that overall symptomatology, audiometric results and VEMP thresholds return to normal values post-obliteration, confirming the continuing success of the MFC approach for SCDS obliteration.

Preoperative computed tomography scan may fail to predict perilymphatic gusher.

OBJECTIVES: A stapes gusher is a very rare event in ear surgery, but the consequences for hearing can be dramatic. It can usually be predicted by characteristic radiologic abnormalities. We report 2 cases of gusher without any abnormalities seen on the preoperative computed tomography scans. METHODS: The first case was in a 30-year-old man with a bilateral mixed hearing loss. The gusher occurred after a stapedotomy performed with a microdrill. The oval window was plugged with a vein graft, and a fluoroplastic piston was inserted. The second case was in a 39-year-old woman with a family history of hearing loss who presented with a bilateral mixed hearing loss. The footplate was fractured during the stapedotomy drilling and was covered with a temporalis fascia graft that was fixed with a fluoroplastic piston. RESULTS: The first patient had no cerebrospinal fluid leakage and no vertigo or tinnitus. He did have a sensorineural hearing loss. The second patient had dizziness and tinnitus. Postoperative magnetic resonance imaging scans were performed, but again no features were identified that might have predicted these cases. CONCLUSIONS: Surgeons should be reminded that a preoperative computed tomography scan may fail to detect the risk of a perilymphatic gusher.

Early computed tomography findings of the inner ear after stapes surgery and its clinical correlations.

OBJECTIVE: Pneumolabyrinth resulting from temporal bone trauma and stapes luxation has been associated with sensorineural hearing loss (SNHL). The principal purpose of this study was to determine the incidence and volume of pneumolabyrinth after stapedotomy in which iatrogenic perilymphatic fistula is created and to also correlate this with possible hearing loss and vertigo. STUDY DESIGN: Prospective study. SETTING: Tertiary referral center. PATIENTS AND METHODS: Fifty stapedotomy patients were operated on for otosclerosis, and of those 50, 20 underwent high-resolution computed tomography (CT) on the first day, 10 on the third day, and 20 on the seventh day. The patients followed up regarding SNHL and vertigo that could develop postoperatively, and the correlation of such complications with HRCT findings was examined. RESULTS: The 20 patients who had high-resolution CT (HRCT) on the first day all presented with pneumolabyrinth, and none of the 20 patients who underwent HRCT on the seventh day had pneumolabyrinth. Postoperatively, 92% of the patients had less than 20 dB and 62% had less than 10 dB air-bone gap. None of the patients had SNHL or persistent vertigo. There was no correlation between pneumolabyrinth and hearing loss or vertigo. CONCLUSION: Pneumolabyrinth is a radiological sign of perilymphatic fistula and has no effect on sensorineural hearing loss and vertigo. Observing pneumolabyrinth during the early postoperative stage should not necessarily implicate a complication; however, pneumolabyrinth after the first week supported with the clinical symptoms of perilymphatic fistula would be a meaningful finding.

Spontaneous cholesteatoma of the external auditory canal: the utility of CT.

Spontaneous external auditory canal (EAC) cholesteatoma is a rare disease. The symptoms are nonspecific. It is diagnosed by clinical examination and radiological investigation. The clinical examination alone is often insufficient for accurately assessing spread of the cholesteatoma into the temporal bone, meaning cross-sectional imaging modalities are required, and specifically computed tomography. We report three cases of spontaneous cholesteatoma of the external auditory canal. All of our patients underwent surgery. In two cases, the cholesteatoma was restricted to the external auditory canal, while in one case, it was complicated by a fistula with the lateral semicircular canal. Good anatomical and functional results were obtained in all three cases, with the external auditory canal patent and a good calibre on completion.

Crural attachment to promontory case report: implications for stapes development.

Understanding of the embryologic origin of the stapes remains controversial. Theories diverge upon whether the entirety of the stapes arises from a single source versus the footplate and suprastructure arising from distinct sources. A 12-year-old boy with left-sided conductive hearing loss had computed tomography of the temporal bone, revealing an inferiorly displaced left stapes, and a nonspecific density in the left Prussak's space. Exploratory tympanotomy revealed the crura of the stapes to be attached to the promontory. The stapes footplate was located in the oval window and was mobile.

Audiological and surgical evidence for the presence of a third window effect for the conductive hearing loss in DFNX2 deafness irrespective of types of mutations.

The objective of this study was to clarify the cause of the air-bone gap in incomplete partition (IP) type III cases according to the POU3F4 gene (DFNX2) mutation type. A retrospective analysis of patient medical records was done in a tertiary referral medical center. Five IP type III patients proved to be carrying a mutation in or affecting POU3F4. The hearing and the middle ear status at either exploratory tympanotomy or cochlear implantation from these DFNX2 cases was reviewed. Four of five unrelated IP type III patients harbored a point mutation of POU3F4 and the fifth patient carried a large genomic deletion upstream to POU3F4. Two of the four DFNX2 patients carrying a point mutation had moderate to severe mixed hearing loss with a substantial amount of air-bone gap. These patients underwent exploratory tympanotomy to identify the cause of their hearing loss. The other three patients, including one carrying a large deletion, had profound hearing loss at presentation and received a cochlear implant. In the exploratory tympanotomy group with a substantial amount of air-bone gap and a point mutation (n = 2), one patient had a perfect ossicular chain with normal mobility, a positive ipsilateral stapedial reflex, and a positive round window reflex. In the cochlear implantation group (n = 3), we found a stapes with normal mobility and a positive round window reflex in one patient who harbored a large genomic deletion upstream to POU3F4. We concluded that the probable presence of the third window effect is not limited to the particular type of POU3F4 mutation.

Inner ear anomalies seen on CT images in people with Down syndrome.

BACKGROUND: Although dysplasia of inner ear structures in Down syndrome has been reported in several histopathological studies, the imaging findings have not been widely studied. OBJECTIVE: To evaluate the prevalence and clinical significance of inner ear anomalies detected on CT images in patients with Down syndrome. MATERIALS AND METHODS: The temporal bone CT images of patients with Down syndrome were assessed for inner ear anomalies; clinical notes and audiograms were reviewed for hearing loss. Logistic regression models were employed to identify which CT findings were associated with sensorineural hearing loss (SNHL). RESULTS: Inner ear anomalies were observed in 74.5% (38/51) of patients. Malformed bone islands of lateral semicircular canal (LSCC), narrow internal auditory canals (IACs), cochlear nerve canal stenoses, semicircular canal dehiscence (SCCD), and enlarged vestibular aqueducts were detected in 52.5% (53/101), 24.5% (25/102), 21.4% (21/98), 8.8% (9/102) and 2% (2/101) of patients' ears, respectively. IAC stenosis had the highest odds ratio (OR = 5.37, 95% CI: 1.0-28.9, P = 0.05) for SNHL. CONCLUSION: Inner ear anomalies occurred in 74.5% of our population, with malformed (<3 mm) bone island of LSCC being the most common (52.5%) anomaly. Narrow IAC was seen in 24.5% of patients with Down syndrome and in 57.1% of ears with SNHL. High-resolution CT is a valuable for assessing the cause of hearing loss in people with Down syndrome.