Diagnostic Value of Cone-Beam Computed Tomography in Conductive or Mixed Hearing Loss with Intact Tympanic Membrane.

BACKGROUND: Conductive or mixed hearing loss with an intact tympanic membrane is a group of diseases characterized by similar clinical symptoms. Definitive diagnosis depends on the findings of exploratory tympanic surgery. Cone-beam computed tomography (CBCT) has great potential for middle ear imaging. This study evaluated the diagnostic value of CBCT for conductive or mixed hearing loss with an intact tympanic membrane. METHODS: CBCT and high-resolution computed tomography (HRCT) imaging data were collected from patients with an intact eardrum who received medical treatment in our hospital for conductive or mixed hearing loss from October 2020 to May 2023. The imaging characteristics and diagnostic values of CBCT and HRCT were analyzed. RESULTS: A total of 137 patients who met the inclusion criteria and underwent CBCT were enrolled, including 89 with otosclerosis, 41 with ossicular chain interruption, and 7 with tympanosclerosis. CBCT clearly displayed a middle ear focus, such as low-density lesions located in the fissula ante fenestram, ossicular chain malformation or dislocation, and tympanic calcification foci. The area under the curve values for otosclerosis, ossicular chain interruption, and tympanic sclerosis were 0.934, 0.967, and 0.850, respectively. CBCT was more effective than HRCT for visualizing the lenticular process, incudostapedial joint, and stapes footplate. CONCLUSIONS: CBCT of the middle ear demonstrated higher-quality imaging to improve the diagnosis of conductive or mixed hearing loss with an intact tympanic membrane. Therefore, CBCT is recommended for further investigation of noninflammatory diseases of the middle ear with no special findings on HRCT.

Frequency and specific characteristics of the incomplete partition type III anomaly in children.

OBJECTIVES/HYPOTHESIS: To determine the frequency of the incomplete partition type III anomaly and the genetic and clinical features associated with POU3F4 mutations in children with hearing loss. STUDY DESIGN: Retrospective case series from 2000 to 2014 at the National Hospital Organization Tokyo Medical Center and collaborating hospitals. METHODS: A total of 1,004 patients (from 938 families) who had hearing loss by 10 years of age and had undergone computed tomography scanning of their temporal bones were enrolled in this genetic, clinical, and radiological study. RESULTS: The incomplete partition type III anomaly was identified in six patients (0.6%), each of whom had an enlargement of the vestibular aqueduct at the end close to the vestibule. The six patients also had POU3F4 variants, and a genetic analysis revealed frameshift deletions in three patients, a missense variant in two patients of the same family, and a large deletion in one patient. Three of the six patients with POU3F4 variants were sporadic cases, and in one patient the genetic mutation occurred de novo. CONCLUSIONS: It was indicated that POU3F4 mutations can be predicted by incomplete partition type III anomaly by radiological examination of the inner ear. All six of the patients showed mixed hearing loss, but none showed fluctuations in hearing, which may be related to the lack of vestibular aqueduct enlargement at the operculum. LEVEL OF EVIDENCE: 4 Laryngoscope, 127:1663-1669, 2017.

Cone beam computed tomography after round window vibroplasty: do the radiological findings match the auditory outcome?

CONCLUSION: The cone beam computed tomography (CBCT) imaging technique has proved to be reliable for assessing the appropriate positioning of the floating mass transducer (FMT) in the round window (RW) niche, although some parameters do not seem to be essential for achieving a satisfactory functional outcome. OBJECTIVES: To evaluate the role that specific imaging parameters derived from CBCT of the temporal bone have for predicting the functional outcome after RW vibroplasty (RW-VP). METHODS: CBCT imaging was carried out in a homogeneous group of patients who presented with a mixed type of hearing loss after open tympanoplasty. Three arbitrary radiological parameters were taken into account: the FMT/RW membrane contact, bony contacts of the FMT margins, and the inferior FMT tissue support. The audiological assessment took into consideration the PTA4 (500-4000 Hz), the PTA2 (125-250 Hz), and the word recognition score (WRS) in quiet and in noise. RESULTS: One subject presented with all positive CBCT parameters and showed a good, but not the best auditory performance among the study group. In the majority of the subjects, with a satisfactory postoperative hearing improvement, at least two of the three radiological parameters were present. In comparison with the unaided condition, an improvement in both the PTA4 and PTA2 was found in all the subjects.

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.

Computed tomographic analysis of outer calvarial thickness for osseointegrated bone-anchored hearing system insertion.

INTRODUCTION: Osseointegrated bone-anchored hearing systems (BAHSs) are a useful tool in auditory rehabilitation for single-sided deafness and conductive/mixed hearing loss. They rely on adequate osseointegration of titanium implants, which can be limited by calvarial thickness. This study examines adult computed tomographic (CT) temporal bone normative data for calvarial thickness in the areas commonly recommended for BAHS insertion and identifies hazards that may compromise the osseointegration process. METHODS: Prospective analysis of 100 consecutive adult helical CT scans. Calvarial thickness was measured in axial and coronal planes 5.5 cm posterior to the superior external auditory canal at 6 vertical points (EAC, +1 cm, +2 cm, +3 cm, +4 cm, and +5 cm). Other parameters measured include temporal bone pneumatization and the presence of suture lines, bone marrow, and vascular structures. RESULTS: A total of 195 temporal bones were examined in 100 patients. Mean patient age was 60.9 years, of whom 54.4% were men and 45.6% were women. Mean calvarial thickness was greatest at +1 cm above the EAC level (6.3 mm) and thinnest at +4 cm (5.1 mm). Of temporal bones, 55% had at least 1 site thinner than 4 mm and 21% had at least 1 site thinner than 3 mm. Air cells and suture lines were more likely to be encountered within 2 cm above the EAC level, and marrow space is more likely to be encountered 3 to 4 cm above the EAC level. DISCUSSION: Selecting a position 3 to 4 cm above the level of the EAC is more likely to result in dural exposure for a 3-mm BAHS abutment, especially in men. Selecting a position near the level of the EAC provides thicker bone, but the surgeon is more likely to encounter suture line or enter mastoid air cells. Preoperative CT imaging may be a useful tool in evaluating calvarial thickness and hazards when planning BAHS insertion in the adult population.

[Persistent stapedial artery with otosclerosis]. / Artère stapédienne persistante et ankylose stapédovestibulaire.

OBJECTIVES: A persistent stapedial artery is a rare vascular malformation. This diagnosis is based on CT scan and intraoperative findings. MATERIAL AND METHODS: The case of a 19-year-old woman with a persistent stapedial artery found during stapes surgery is reported. This vascular malformation was explored with a CT scan showing the bilaterality of this anatomical variation and signs of associated otosclerosis. RESULTS: This malformation was successfully coagulated with laser allowing the stapedotomy to be completed. CONCLUSIONS: A persistent stapedial artery is not a contraindication to stapedotomy because it can be safely coagulated during the same procedure.

Imaging of hearing loss.

In this article, we review the common entities causing the hearing loss and divide these pathologies into conductive hearing loss, sensorineural hearing loss, and mixed hearing loss. With this format, congenital pathologies are addressed first followed by the acquired entities. We review the common pathologies and the imaging findings affecting the hearing pathways from outside to inside, starting at the external auditory canal and moving inward toward the midbrain.

Traumatic stapes fracture with rotation and subluxation into the vestibule and pneumolabyrinth.

A 41-year-old man presented after forceful penetrating ear injury. He had incapacitating vestibular symptoms. Computed tomography revealed pneumolabyrinth with a fractured stapes that was >90 degrees rotated and subluxed into the vestibule, such that the crura and capitulum could be seen in the vestibule. Surgical repair reversed the vestibular symptoms, but there was persistent hearing loss. Stapes fractures are unusual and rarely associated with subluxation into the vestibule. When this does occur, there is usually simple footplate depression. This case demonstrates a rare stapes fracture with pneumolabyrinth and >90 degrees stapes rotation, then subluxation into the vestibule. Laryngoscope, 2009.

Prospective radiological study concerning a series of patients suffering from conductive or mixed hearing loss due to superior semicircular canal dehiscence.

The aim of this study is to appreciate the incidence of patients with isolated conductive hearing loss with normal drum due to superior semicircular canal dehiscence (SCD). It is a prospective radiological study. Two hundred and seventy-two patients with a normal drum suffering from isolated unilateral or bilateral conductive or mixed hearing loss were included in a prospective radiological study. A high resolution computerized tomography (HRCT) was performed in all the patients. Those who were found to have a unilateral or bilateral SCD underwent further etiological, clinical, audiologic evaluation. Ten patients with conductive or mixed hearing loss were found to have a unilateral or bilateral SCD. The disease was bilateral in five cases, and most often associated with a dehiscence of the tegmen tympani on both sides, supporting the theory of the congenital nature of the disease. There was no clear correlation between symptoms and the size of the SCD. Because patients were not suffering from incapacitating vestibular symptoms, they were not operated for surgical occlusion of the SCD, and were referred to a hearing aid specialist to improve hearing. Conductive or mixed hearing loss due to SCD is relatively frequent, justifying in our opinion that a systematic HRCT be carried out before surgery of any patient with conductive hearing loss.

Clinics in diagnostic imaging (111): X-linked congenital mixed deafness syndrome.

Two siblings, boys aged five and six years old, presented with mixed hearing loss. Computed tomography of the temporal bones showed bulbous dilatation of the internal auditory canals and incomplete separation with the basal turn of the cochlear, consistent with the diagnosis of X-linked congenital progressive mixed deafness syndrome. The diagnosis and management of this rare condition is discussed.

Relationship between CT densitometry with a slice thickness of 0.5 mm and audiometry in otosclerosis.

The appropriate cutoff Hounsfield unit (HU) value for the diagnosis of otosclerosis was determined and the correlation between the bone conduction threshold and the findings of computed tomography (CT) densitometry investigated. CT images, 0.5-mm thick, were evaluated in 24 ears with otosclerosis and 19 control ears. Eight regions of interest were set around the otic capsule. The mean HU values in the area anterior to the oval window (A-OW) and anterior to the internal auditory canal (A-IAC) were significantly lower in otosclerosis than in controls. Based on receiver operating characteristic (ROC) analysis, the cutoff HU value in A-OW was determined to be 2,187.3 HU. The mean HU value in retrofenestral otosclerosis was significantly lower in the area A-OW, A-IAC and around the cochlea than in controls. Based on ROC analysis, the cutoff HU value in the latter was determined to be 2,045 HU. A statistically significant correlation was found between the density of the area A-OW and the hearing level at 500 and 1,000 Hz, and between the density of the area around the cochlea and the hearing level at most frequencies. These results suggest the semi-automated diagnosis of otosclerosis may be possible.

Vertically oriented internal auditory canal in an 8-year-old with hearing loss.

To report a unique orientation of the internal auditory canal and possible association with congenital hearing loss. Retrospective chart review of an 8-year-old Hispanic male with a mixed hearing loss. Uniquely abnormal orientation of the internal auditory canal in a patient with apparently normal cochleovestibular structures and a mixed hearing loss. A vertically oriented IAC is a rarely described anatomical anomaly of the temporal bone that may have associations with congenital hearing loss.