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Levent Sennaroglu

Publications and source records attributed to Levent Sennaroglu.

10 recordsLinked to original sources

Surgical results of cochlear implantation in malformed cochlea.

OBJECTIVE: To report the surgical aspects of cochlear implantation in malformed cochlea. SETTING: Tertiary care center. STUDY DESIGN: Retrospective case review. METHODS: Between November 1997 and October 2004, 20 patients with inner ear malformations were implanted in our department. The age range was between 2 and 37 years (average, 8.8 yr). The anomalies were classified according to Sennaroglu and Saatci classification. There were two patients with common cavity deformity, four cases of incomplete partition (IP) type I (cystic cochleovestibular malformation), four cases of IP type II (classical Mondini's deformity), nine patients with large vestibular aqueduct (LVA) syndrome, and one patient with X-linked deafness. RESULTS: Standard transmastoid facial recess approach was used in 17 patients (three patients with IP I, four patients with IP II, and nine patients with LVA syndrome). In the remaining patient with IP I, because of the dehiscent and anteriorly located facial nerve, the surgical approach had to be modified, and an anteroposterior approach was used. After elevating the tympanomeatal flap, the electrode was inserted through the ear canal and then transferred to the mastoid through a full-length cut produced in the ear canal. The flap then returned to its place. In the patients with common cavity deformity, the electrode was inserted by the transmastoid labyrinthotomy approach. Facial nerve had an abnormal course in four patients, but no patient had facial weakness postoperatively. Cerebrospinal fluid gusher was encountered in four patients, whereas oozing was present in five patients. It seems that a slightly larger cochleostomy may reduce postoperative rhinorrhea. The patient with common cavity deformity showed abnormal vestibular stimulation which decreased and was totally abolished during a 3-month period. CONCLUSION: Based on these findings, cochlear implantation is surgically feasible in patients with common cavity, IP types I and II, and LVA. The surgeon should be ready to make modifications in the surgical approach because of the abnormal course of the facial nerve and be ready to produce special precautions to cerebrospinal fluid gusher.

Adolescent↗

Pneumolabyrinth following traumatic luxation of the stapes into the vestibule.

Pneumolabyrinth can result from traumatic luxation of stapes into the vestibule. The diagnosis of stapes luxation following a head injury can be delayed especially if the otoscopic examination is within normal limits. Here a 15-year-old girl presenting with vertigo and nystagmus following a blunt head injury was presented, whose computerized tomography revealed air in the vestibule and cochlea (pneumolabyrinth) and stapes was found to be luxated into the vestibule.

Adolescent↗

Unpartitioned versus incompletely partitioned cochleae: radiologic differentiation.

OBJECTIVE: In the process of evaluating our patients, we realized that the term "Mondini deformity" was being used to describe two different types of incomplete partition of the cochlea. THE First one consisted of an unpartitioned, completely empty cochlea where the interscalar septum and entire modiolus were absent, giving the cochlea a cystic appearance; a grossly dilated vestibule accompanied this lesion. The second pathology fitted the classic description of Mondini deformity, consisting of a normal basal turn and cystic apex (where the middle and apical turns form a cystic cavity), dilated vestibule, and enlarged vestibular aqueduct. This study was planned to investigate the differences between the two types of incomplete partition for inner ear malformations based on radiologic features. STUDY DESIGN: We conducted a retrospective review of temporal bone computed tomography (CT) findings. METHODS: The subjects were 18 patients with profound bilateral sensorineural hearing loss who had high-resolution CT with contiguous 1-mm thick images obtained through the petrous bone in axial sections. The CT results were reviewed as incomplete partition type I (IP-I) and type II (IP-II). Incomplete partition type I (unpartitioned cochlea, cystic cochleovestibular malformation) is defined as a malformation in which the cochlea lacks the entire modiolus and interscalar septa, resulting in a cystic appearance and there is an accompanying grossly dilated vestibule. In incomplete partition type II (incompletely partitioned cochlea, the Mondini deformity), there is a cochlea comprised of a normal basal turn and cystic apex accompanied by a minimally dilated vestibule and enlarged vestibular aqueduct (VA). Measurements involving the cochlea, vestibule, vestibular aqueduct, and internal auditory canal (IAC) were done to determine the characteristic features of these pathologies. RESULTS: : Thirteen ears had IP-I and 18 ears had IP-II anomaly. The size of the cochleae in both anomalies showed no significant difference from the normal findings. Only the internal architecture was different. All ears with IP-I had grossly dilated vestibules. Although both anomalies demonstrated vestibular dilatation, the degree of that was minimal in patients with IP-II. In IP-I anomalies, the IAC was larger than that in IP-II anomalies. An enlarged VA accompanied all cases of IP-II, whereas only one of the patients with IP-I had VA that could be demonstrated on CT. In all cases, the VA findings were symmetric on both sides: normal or enlarged. CONCLUSION: Inner ear measurements on radiologic findings in this study confirmed the presence of two different types of incomplete partition: IP-I (unpartitioned cochlea, cystic cochleovestibular malformation) and IP-II (incompletely partitioned cochlea, the classic Mondini deformity). The type I malformation is less differentiated than the type II malformation. Classic Mondini deformity has three components (a cystic apex, dilated vestibule, and large vestibular aqueduct), whereas type I malformation has an empty, unpartitioned cochlea and dilated vestibule without an enlarged VA. Mondini deformity represents a later malformation, so the degree of dysplasia is milder than that in type I. Not only the appearance, but also the measurements of the inner ear structures would be helpful in determining the type of malformation.

Adolescent↗

Petrous anatomy for middle fossa approach.

OBJECTIVE: The objective was to describe the relationship of anatomical landmarks required for the middle fossa approach to lesions of the petrous apex and internal auditory canal (IAC). Landmarks for safe identification of the IAC are defined, as are two zones (safe zones I and II) anterior and posterior to the IAC. STUDY DESIGN: Temporal bone anatomical study. METHODS: Ten temporal bones underwent high-resolution computed tomography followed by wet bench dissection. A set of 39 different distances between vital structures was measured, where possible, from both radiology films and under the microscope. Mean, median, minimum, and maximum measurements of all distances were determined. Angular measurements were made using a specially designed instrument. RESULTS: Measurements were made in an anatomical position to mimic the middle fossa surgical technique. Measurements are presented for the superior surface of the temporal bone from the sigmoid sinus and inner table to vital structures, from the anterior and posterior petrous apex, and from the IAC. CONCLUSIONS: Petrous apex anatomical knowledge is required for the safe middle fossa approach to the IAC and petrous apex. Two safe zones are defined that should prevent damage to the cochlea and the superior semicircular canal.

Cephalometry↗

A new classification for cochleovestibular malformations.

OBJECTIVE: The report proposes a new classification system for inner ear malformations, based on radiological features of inner ear malformations reviewed in 23 patients. STUDY DESIGN: The investigation took the form of a retrospective review of computerized tomography findings relating to the temporal bone in 23 patients (13 male and 10 female patients) with inner ear malformations. The subjects were patients with profound bilateral sensorineural hearing loss who had all had high-resolution computed tomography (CT) with contiguous 1-mm-thick images obtained through the petrous bone in axial sections. METHODS: The CT results were reviewed for malformations of bony otic capsule under the following subgroups: cochlear, vestibular, semicircular canal, internal auditory canal (IAC), and vestibular and cochlear aqueduct malformations. Cochlear malformations were classified as Michel deformity, common cavity deformity, cochlear aplasia, hypoplastic cochlea, incomplete partition types I (IP-I) and II (IP-II) (Mondini deformity). Incomplete partition type I (cystic cochleovestibular malformation) is defined as a malformation in which the cochlea lacks the entire modiolus and cribriform area, resulting in a cystic appearance, and there is an accompanying large cystic vestibule. In IP-II (the Mondini deformity), there is a cochlea consisting of 1.5 turns (in which the middle and apical turns coalesce to form a cystic apex) accompanied by a dilated vestibule and enlarged vestibular aqueduct. RESULTS: Four patients demonstrated anomalies involving only one inner ear component. All the remaining patients had diseases or conditions affecting more than one inner ear component. Eight ears had IP-I, and 10 patients had IP-II. Ears with IP-I had large cystic vestibules, whereas the amount of dilation was minimal in patients with IP-II. The majority of the semicircular canals (67%) were normal. Semicircular canal aplasia accompanied cases of Michel deformity, cochlear hypoplasia, and common cavity. In 14 ears, the IAC had a defective fundus at the lateral end. In two ears the IAC was absent. In all seven cases of common cavity malformations, there was a bony defect at the lateral end of the IAC. In five of them the IAC was enlarged, whereas in two the IAC was narrow. All patients with IP-I had an enlarged IAC, whereas in patients with type II disease, four had a normal IAC and 10 had an enlarged IAC. All cases of IP-II had an enlarged vestibular aqueduct, whereas this finding was not present in any of the cases of IP-I. In all cases, the vestibular aqueduct findings were symmetrical on both sides (simultaneously normal or enlarged). No patient demonstrated enlargement or any other abnormalities involving the cochlear aqueduct. CONCLUSIONS: Radiological findings of congenital malformations in the present study suggested two different types of incomplete partition. Cystic cochleovestibular malformation (IP-I) and the classic Mondini deformity (IP-II). The type I malformation is less differentiated than the type II malformation. Classic Mondini deformity has three components (a cystic apex, dilated vestibule, and large vestibular aqueduct), whereas type I malformation has an empty, cystic cochlea and vestibule without an enlarged vestibular aqueduct. Mondini deformity represents a later malformation, so the amount of dysplasia is much less than in type II. Therefore, it is more accurate and useful for clinical purposes to classify these malformations (in descending order of severity) as follows: Michel deformity, cochlear aplasia, common cavity, IP-I (cystic cochleovestibular malformation), cochlear hypoplasia, and IP-II (Mondini deformity). Only in this way can these complex malformations be grouped precisely and the results of cochlear implantation compared.

Child↗

Anteroposterior approach with split ear canal for cochlear implantation in severe malformations.

OBJECTIVE: To present an anteroposterior approach with split ear canal technique in severe malformed ears in which cochlear implantation is not possible through the standard facial recess approach. SETTING: The operation was performed at Hacettepe University Medical Faculty, which is a tertiary care center. STUDY DESIGN: Case report. PATIENT: A 4-year-old female patient with severe Mondini malformation whose facial nerve was completely dehiscent and overlying the stapes and round window. INTERVENTION: The anteroposterior approach was used, and the middle ear was entered after the tympanomeatal flap was elevated. The posterior wall of the ear canal was split longitudinally with a diamond drill. The electrode was inserted easily through the ear canal and then transferred into the mastoid. CONCLUSION: The anteroposterior approach with split ear canal method may be used if, during facial recess, the landmarks in the middle ear (stapes, stapedius tendon, round window, and promontory) cannot be identified clearly because of an abnormal facial nerve (coursing anteriorly, preventing the use of a drill). It is an alternative for the canal wall down procedure.

Abnormalities, Multiple↗

Magnetic resonance imaging versus computed tomography in pre-operative evaluation of cochlear implant candidates with congenital hearing loss.

Recent reports indicate that the cochlear nerve may be absent in some cases of congenital sensorineural hearing loss. The aim of this prospective study was to determine the incidence of cochlear nerve anomaly in cochlear implant candidates with congenital hearing loss using magnetic resonance imaging (MRI). Twenty-seven patients with congenital profound bilateral sensorineural hearing loss who were being evaluated for the cochlear implant procedure were studied. These patients had high-resolution computerized tomography (CT), through the petrous bone in axial sections. MRI examinations consisted of T1 and turbo spin echo (TSE) T2-weighted 3 mm axial images, and additional 3D Fourier Transform T2-weighted TSE sequences obtained on three different planes (axial, perpendicular and parallel to the internal auditory canal (IAC) i.e. oblique sagittal and coronal, respectively) for the purpose of cochlear nerve demonstration. Results showed that all of the 14 patients with normal CT of the temporal bone, had four distinct nerves in the distal part of the IAC on TSE-MRI. Thirteen patients demonstrated various bony malformations of the cochleovestibular system on CT. MRI revealed the absence of the cochleovestibular nerve in four patients where the IAC was very narrow or completely absent on CT. One patient with severe Mondini malformation who had an enlarged IAC demonstrated an isolated absent cochlear nerve.

Adolescent↗