Wideband Tympanmetry Results of Bone Cement Ossiculoplasty.

OBJECTIVE: We aim to investigate hearing sensitivity and wideband tympanometry results in bone cement ossiculoplasty cases in present study. STUDY DESIGN: A prospective study. SETTING: Ossiculoplasty patients were grouped according to the anatomical location of bone cement application by surgery note. Ossiculoplasty and tympanoplasty patients were retrospectively invited to the clinic and evaluated. 30 bone cement ossiculoplasty cases as well as 30 Type I tympanoplasty cases (intact ossicular chain) and 30 healthy controls were included in the study and Wideband Tympanometry was performed. Tympanometric peak pressure, equivalent middle ear volume, static admittance, tympanogram width, resonance frequency, average wideband tympanometry and absorbance measurements were analyzed. RESULTS: A statistically significant improvement was observed in the hearing levels of all ossiculoplasty and type I tympanoplasty patients (p < 0.05). Bone cement ossiculoplasty groups demonstrated the remarkable differences than the type I tympanoplasty and control group in Wideband Tympanometry test parameters. In some parameters, malleus-stapes and manubriostapedioplasty groups demonstrated similarities to Type I tympanoplasty and control groups. CONCLUSION: Bone cement is an effective application for ossiculoplasty. Wideband tympanometry is a promising method for the evaluation of the middle ear dynamics.

Radiological measurement of cochlear dimensions in cochlear hypoplasia and its effect on cochlear implant selection.

OBJECTIVE: To determine the effect of cochlear dimensions on cochlear implant selection in cochlear hypoplasia patients. METHODS: Temporal bone computed tomography images of 36 patients diagnosed with cochlear hypoplasia between 2010 and 2016 were retrospectively reviewed and compared with those of 40 controls without sensorineural hearing loss. RESULTS: Basal turn length and mid-modiolar height were significantly lower in the cochlear hypoplasia patients with subtypes I, II and III than in the control group (p < 0.001). Mid-scalar length was significantly shorter in subtype I-III patients as compared with the control group (p < 0.001). In addition, cochlear canal length (measured along the lateral wall) was significantly shorter in subtype I-IV patients than in the control group (subtypes I-III, p < 0.001; subtype IV, p = 0.002). CONCLUSION: Cochlear hypoplasia should be considered if basal turn length is less than 7.5 mm and mid-modiolar height is less than 3.42 mm. The cochlear implant should be selected according to cochlear hypoplasia subgroup. It is critically important to differentiate subtype II from incomplete partition type I and subtype III from a normal cochlea, to ensure the most appropriate implant electrode selection so as to optimise cochlear implantation outcomes.

Inner-ear malformations as a cause of single-sided deafness.

OBJECTIVE: To determine the prevalence and distribution of inner-ear malformations in congenital single-sided deafness cases, as details of malformation type are crucial for disease prognosis and management. METHODS: A retrospective study was conducted of 90 patients aged under 16 years with congenital single-sided deafness. Radiological findings were evaluated using computed tomography and magnetic resonance imaging. Inner-ear malformations were identified and cochlear nerve status was determined in affected ears. RESULTS: Out of 90 ears, 42 (46.7 per cent) were found to have inner-ear malformation. Isolated cochlear aperture stenosis was the most common anomaly (n = 18, 20 per cent), followed by isolated cochlear aperture atresia (n = 11, 12.2 per cent) and cochlear hypoplasia (n = 7, 7.8 per cent). Cochlear nerve deficiency was encountered in 41 ears (45.6 per cent). The internal auditory canal was also stenotic in 49 ears (54.4 per cent). CONCLUSION: Inner-ear malformations, especially cochlear aperture anomalies, are involved in the aetiology of single-sided deafness more than expected. The cause of single-sided deafness differs greatly between congenital and adult-onset cases. All children with single-sided deafness should undergo radiological evaluation, as the prognosis and management, as well as the aetiology, may be significantly influenced by inner-ear malformation type.

A study on modelling cochlear duct mid-scalar length based on high-resolution computed tomography, and its effect on peri-modiolar and mid-scalar implant selection.

OBJECTIVE: To determine cochlear duct mid-scalar length in normal cochleae and its role in selecting the correct peri-modiolar and mid-scalar implant length. METHODS: The study included 40 patients with chronic otitis media who underwent high-resolution computed tomography of the temporal bone. The length and height of the basal turn, mid-modiolar height of the cochlea, mid-scalar and lateral wall length of the cochlear duct, and the 'X' line (the largest distance from mid-point of the round window to the mid-scalar point of the cochlear canal) were measured. RESULTS: Cochlear duct lateral wall length (28.88 mm) was higher than cochlear duct mid-scalar length (20.08 mm) (p < 0.001). The simple linear regression equation for estimating complete cochlear duct length was: cochlear duct length = 0.2 + 2.85 × X line. CONCLUSION: Using the mid-scalar point as the reference point (rather than the lateral wall) for measuring cochlear duct mid-scalar length, when deciding on the length of mid-scalar or peri-modiolar electrode, increases measurement accuracy. Mean cochlear duct mid-scalar length was compatible with peri-modiolar and mid-scalar implant lengths. The measurement method described herein may be useful for pre-operative peri-modiolar or mid-scalar implant selection.

Twenty years of experience in revision cochlear implant surgery: signs that indicate the need for revision surgery to audiologists.

OBJECTIVE: To report device failures, audiological signs and other reasons for revision cochlear implant surgery, and discuss indications for revision surgery. METHODS: Revision procedures between November 1997 and August 2017 were retrospectively analysed. Over 20 years, 2181 cochlear implant operations were performed, and 114 patients underwent 127 revision operations. RESULTS: The revision rate was 4.67 per cent. The full insertion rate for revision cochlear implant surgery was 88.2 per cent. The most frequent reasons for revision surgery were: device failure (59 per cent), wound breakdown (9.4 per cent) and electrode malposition (8.7 per cent). The device failure rate was: 2.78 per cent for Advanced Bionics, 1.82 per cent for Cochlear and 5.25 per cent for Med-El systems. The number of active electrodes was significantly increased only for Med-El devices after revision surgery. The most common complaints among 61 patients were: gradually decreased auditory performance, sudden internal device shutdown and headaches. CONCLUSION: The most common reason for revision surgery was device failure. Patients should be evaluated for device failure in cases of: no hearing despite appropriate follow up, side effects such as facial nerve stimulation, and rejection of speech processor use in paediatrics. After revision surgery, most patients have successful outcomes.

The effect of cochlear implant bed preparation and fixation technique on the revision cochlear implantation rate.

OBJECTIVE: This study aimed to determine the effect of the subperiosteal tight pocket technique versus the bone recess with suture fixation technique on the revision cochlear implantation rate and complications. METHODS: This retrospective study included 1514 patients who underwent cochlear implantation by 2 senior surgeons between October 2002 and January 2016. Revision cases were identified and analysed. RESULTS: In all, 52 patients (3.34 per cent) underwent revision cochlear implantation. The revision rate was 7.18 per cent in the subperiosteal tight pocket group versus 2.37 per cent in the bone recess with suture fixation group (p < 0.001). Device failure was the most common reason for revision surgery in both groups. There was a significant difference in the device failure rate between the bone recess with suture fixation group (2.11 per cent) and subperiosteal tight pocket group (6.88 per cent) (p < 0.001). CONCLUSION: Accurate fixation of the cochlear implant receiver/stimulator is crucial for successful cochlear implantation. As the bone recess with suture fixation technique is associated with a lower revision rate and a similar complication rate as the subperiosteal tight pocket technique, it should be the preferred fixation technique for cochlear implantation.

Hacettepe cartilage slicer: a novel cartilage slicer and its performance test results.

OBJECTIVE: This study investigated the performance of a cartilage slicer device referred to as the 'Hacettepe cartilage slicer'. METHODS: Forty-one cartilage pieces were harvested from eight fresh frozen human ears and measured in thickness with a digital micrometer. These pieces were randomly sliced using four different thickness settings and two different types of blades. The thicknesses of the slices and remaining pieces were measured also. Scanning electron microscopy was utilised to determine the surface smoothness of the slices. RESULTS: Thickness results showed a proportional increase with the increasing thickness setting, with a ±0.1 mm margin of error. The measurements showed that over 95 per cent of the slices' structural integrity was preserved. Although both blades provided satisfactory results, scanning electron microscopy revealed that the slices cut with a single bevel blade had superior surface smoothness. CONCLUSION: To our knowledge, the current study is the first to evaluate the performance of a cartilage slicer device. Based on the thickness results, the Hacettepe cartilage slicer fulfilled its design goals: to consistently produce slices at the intended thickness with a ±0.1 mm tolerance, and to preserve over 95.3 per cent of cartilage thickness thereby ensuring undamaged, strong cartilage slices.

Bony cochlear nerve canal and internal auditory canal measures predict cochlear nerve status.

OBJECTIVES: The bony cochlear nerve canal is the space between the fundus of the internal auditory canal and the base of the cochlear modiolus that carries cochlear nerve fibres. This study aimed to determine the distribution of bony labyrinth anomalies and cochlear nerve anomalies in patients with bony cochlear nerve canal and internal auditory canal atresia and stenosis, and then to compare the diameter of the bony cochlear nerve canal and internal auditory canal with cochlear nerve status. METHODS: The study included 38 sensorineural hearing loss patients (59 ears) in whom the bony cochlear nerve canal diameter at the mid-modiolus was 1.5 mm or less. Atretic and stenotic bony cochlear nerve canals were examined separately, and internal auditory canals with a mid-point diameter of less than 2 mm were considered stenotic. Temporal bone computed tomography and magnetic resonance imaging scans were reviewed to determine cochlear nerve status. RESULTS: Cochlear hypoplasia was noted in 44 out of 59 ears (75 per cent) with a bony cochlear nerve canal diameter at the mid-modiolus of 1.5 mm or less. Approximately 33 per cent of ears with bony cochlear nerve canal stenosis also had a stenotic internal auditory canal and 84 per cent had a hypoplastic or aplastic cochlear nerve. All patients with bony cochlear nerve canal atresia had cochlear nerve deficiency. The cochlear nerve was hypoplastic or aplastic when the diameter of the bony cochlear nerve canal was less than 1.5 mm and the diameter of the internal auditory canal was less than 2 mm. CONCLUSION: The cochlear nerve may be aplastic or hypoplastic even if temporal bone computed tomography findings indicate a normal cochlea. If possible, patients scheduled to receive a cochlear implant should undergo both computed tomography and magnetic resonance imaging of the temporal bone. The bony cochlear nerve canal and internal auditory canal are complementary structures, and both should be assessed to determine cochlear nerve status.

New laryngoscope for endoscopic arytenoidectomies.

OBJECTIVE: During an endoscopic arytenoidectomy, an intubation tube must be elevated anteriorly with the laryngoscope to ensure an adequate surgical field. This paper describes a new laryngoscope that has a canal along the outer wall of the body and a ridge which runs along the canal. METHOD: Ten patients underwent endoscopic total arytenoidectomy using this new laryngoscope and 10 patients underwent the same operation using a regular laryngoscope. RESULTS: The duration of all operations ranged between 25 and 65 minutes, with a median duration of 42.5 minutes. The median duration with the new laryngoscope was 39 minutes, and that with the regular laryngoscope was 49 minutes; this difference was statistically significant (p < 0.05). CONCLUSION: This new laryngoscope shortened the duration of the endoscopic arytenoidectomy and facilitated the procedure by enlarging the surgical field. This new laryngoscope may be a beneficial surgical instrument for posterior endoscopic laryngeal operations.