Morphometric Analysis of the Retrolabyrinthine Approach to the Posterior Fossa.

INTRODUCTION: The retrolabyrinthine approach provides shorter working distance and less cerebellar retraction compared with the retrosigmoid approach to the internal acoustic canal (IAC) and cerebellopontine angle cistern. However, exposure of the ventral surface of the brainstem and petroclival region may be restricted. Trautmann's triangle (TT), an area intimately related to this region, demonstrates significant anatomical variability, which may adversely affect the ease of the approach. The aim of this study is to evaluate anatomic parameters of the posterior fossa that may anticipate a challenging situation in approaching the IAC and the petroclival region through the retrolabyrinthine approach. METHODS: It was performed a radioanatomic analysis of 75 cerebral angiotomography exams to identify parameters that could potentially reduce areas of surgical exposure. RESULTS: Large variations were observed in the area of exposure of the TT (553%) and the height of the jugular bulb (234%). Shorter distances from the sigmoid sinus to the posterior semicircular canal and high-riding jugular bulb were associated with smaller areas of exposure. Dominant and laterally positioned sigmoid sinuses and less pneumatized mastoids were associated with potentially unfavorable conditions, including a narrower angle of attack to the IAC. Increased petrous slopes and petroclival angles were associated with smaller petroclival areas and shallower clival depths. CONCLUSIONS: This study of the posterior fossa reveals remarkable anatomic variation in the region. These findings should be taken into consideration during the preoperative planning of retrolabyrinthine approaches in order to offer safer and more effective surgical procedures.

Does a patient with acquired arbovirus infection have a hearing impairment? A scoping review of hearing changes in an adult with Dengue, Chikungunya, and Zika.

OBJECTIVES: To identify and understand the evidence regarding hearing changes related to acquired Dengue, Chikungunya, and Zika virus infection in adult individuals. METHODS: A scoping review was performed according to the recommendations of The Joanna Briggs Institute and guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews in the Embase, PubMed/Medline, ScienceDirect, Scopus, and Web of Science databases without restriction on language and year of publication. Case studies, observational studies, and clinical trials reporting hearing loss in adult subjects (>18-60 years of age) of both sexes with DENV, CHIKV, or ZIKV diagnosed by positive molecular/serological examination by RT-PCR or IgM/IgG by ELISA method were included. RESULTS: Thirteen studies met the inclusion criteria and were selected for review. The occurrence of auditory symptoms caused by arboviroses and the presence of permanent or transient sensorineural hearing loss was variable in adults. CONCLUSIONS: Dengue, Chikungunya, and Zika infections in adults are associated with a variety of auditory symptoms. The frequency of permanent or transient sensorineural hearing loss is low but not negligible.

The Extra-Extended Translabyrinthine Approach for Resection of Large Acoustic Neuroma: 2-Dimensional Operative Video.

The extended translabyrinthine approach to acoustic neuroma (AN) was created to allow improved visualization and access to larger tumors.1,2 The dural opening, however, remained confined to the presigmoid space. Other authors have introduced modifications to increase the dura exposure around the internal auditory canal (IAC).3-5 The extra-extended translabyrinthine approach was conceptualized by the senior author (CC) to maximize AN exposure and early cranial nerve identification. The tentorial peeling was added to allow extradural mobilization of the temporal lobe.6 This allows further safe bone removal around the IAC and petrous apex and consistent opening of the facial canal at IAC fundus. This modification creates 280-to-360-degree dura exposure at the IAC. The dural opening extends to the petrous apex superiorly and the prepontine arachnoid cistern inferiorly and includes resection of a tentorium dural flap created by the tentorial peeling.6 This exposure allows for near circumferential exposure of the tumor and early identification of the glossopharyngeal nerve in the cochlear aqueduct area, the trigeminal nerve at the porus trigeminal, and the facial nerve (FN) at IAC fundus. In addition, this ample exposure permits identification of the FN trajectory in the tumor capsule before any tumor dissection. We present a detailed video of extra-extended translabyrinthine approach technique in a patient with a large left AN (Hannover classification T4B).7 This video does not involve any human research projects not requiring Institutional Review Board/ethic committee approval. The patient consented to the procedure and to the publication of his image. Complete resection was obtained. The FN function was House-Brackman I/VI.

Descriptive study of goat external and middle ear through computed tomography and endoscopic evaluation, compared with the human ear.

OBJECTIVE: To describe the external and middle ear of goats, using computed tomography and endoscopic dissection, comparing them with the anatomy of the human ear, aiming to evaluate the viability of this animal model for training in otological endoscopic surgery. METHODS: Images of the external and middle ear of goats were produced by computed tomography in the coronal and axial planes and analyzed. The radiological anatomy of the external and middle goat and human ear are described. Some measures of surgical interest were described, such as the length of the external auditory canal, external and internal cross-sectional area of the external auditory canal, middle ear depth, vertical angle of the external auditory canal, length of malleus and incus. After the tomographic study, we analyzed the importance of evaluations through the endoscopic dissection of the goat ear. RESULTS: The bony canal is extremely tortuous and shows a bony prominence with significant elevation near the lower edge of the tympanic membrane. The middle ear has a large tympanic bulla in the hypotympanum region. The malleus is shaped similarly to that of the human, but its handle is located anterior to its head. The mastoid is not pneumatized. Compared to the human mastoid, there was a statistically significant difference in the external and internal cross-sectional area, at the depth of the middle ear, in the vertical angle of the canal and in the length of the incus. CONCLUSION: Goat morphometric anatomy showed that this model is suitable for surgical simulation in the initial training for endoscopic otological surgery. It is an important contribution to the development of skills to accelerate the subsequent endoscopic otological surgical training in humans, despite some differences found.

Use of nasal mucosa graft in tympanoplasty.

INTRODUCTION: Tympanoplasty techniques with different types of graft have been used to close tympanic perforations since the 19th century. Tragal cartilage and temporalis fascia are the most frequently used types of graft. They lead to similar functional and morphological results in most cases. Although little published evidence is present, nasal mucosa has also been shown to be a good alternative graft. OBJECTIVE: Surgical and audiological outcomes at the six-month follow-up in type I tympanoplasty using nasal mucosa and temporalis fascia grafts were analyzed. METHODS: A total of 40 candidates for type I tympanoplasty were randomly selected and divided into the nasal mucosa and temporalis fascia graft groups with 20 in each group. The assessed parameters included surgical success; the rate of complete closure of tympanic perforation and hearing results; the difference between post- and pre-operative mean quadritonal airway-bone gap, six months after surgery. RESULTS: Complete closure of the tympanic perforation was achieved in 17 of 20 patients in both groups. The mean quadritonal airway-bone gap closures were11.9 and 11.1 dB for the nasal mucosa and temporalis fascia groups, respectively. There was no statistically significant difference between the groups. CONCLUSION: The nasal mucosa graft can be considered similar to the temporal fascia when considering the surgical success rate of graft acceptance and ultimate audiological gain.

Cortical Auditory Evoked Potentials in Children with Prenatal Exposure to Zika Virus.

Prenatal exposure to ZIKV can cause neurologic and auditory damage. The electrophysiological responses obtained by Cortical Auditory Evoked Potentials (CAEP) may provide an objective method to investigate the function of cortical auditory pathways in children exposed to ZIKV. This case series analyzed the findings of CAEP in prenatal-period ZIKV-exposed children with and without microcephaly. The CAEP was performed in a total of 24 children. Five magnetic resonance imaging (MRI) images of the inner ear and brain of microcephalic children were analyzed and compared with CAEP measurements. Ventriculomegaly (80%), cortical/subcortical calcification (80%), and brain reduction (60%) were the most common alterations in the MRI. The P1-N1-P2 complex of the CAEP was observed in all children evaluated. The peak N2 was absent in two children. In the comparison of the CAEP measurements between the groups, children with microcephaly presented a higher amplitude of P2 (p = 0.017), which may reflect immaturity of the auditory pathways. Microcephalic and normocephalic children with prenatal exposure to ZIKV presented with the mandatory components of the CAEPs, regardless of changes in the CNS, suggesting that this population has, to some extent, the cortical ability to process sound stimuli preserved.

Tentorial Peeling: Surgical Extradural Navigation to Protect the Temporal Lobe in the Focused Combined Transpetrosal Approach.

BACKGROUND: Transpetrosal approaches have been used for treatment of tumors in the petroclival region for many years. Injury to the temporal lobe, however, has been a potential drawback of the techniques described to date. OBJECTIVE: To describe modifications of the transpetrosal surgical technique, which allows extradural manipulation of the temporal lobe during the focused combined transpetrosal approach. This extra layer of protection avoids mechanical brain retraction, direct trauma to the temporal lobe and disruption of the local venous structures. METHODS: The present manuscript describes an innovative technical nuance based on the combination of the focused combined transpetrosal approach, the peeling of the dural layers of the tentorium, and the reverse peeling of the middle fossa dura mater. Ample illustrative material is provided and illustrative cases are presented. CONCLUSION: Peeling of the dural layers of the tentorium is a promising modification of the transpetrosal approach to increase the safety of the temporal lobe manipulation.

Does a patient with acquired arbovirus infection have a hearing impairment? A scoping review of hearing changes in an adult with Dengue, Chikungunya, and Zika

Abstract Objectives To identify and understand the evidence regarding hearing changes related to acquired Dengue, Chikungunya, and Zika virus infection in adult individuals. Methods A scoping review was performed according to the recommendations of The Joanna Briggs Institute and guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews in the Embase, PubMed/Medline, ScienceDirect, Scopus, and Web of Science databases without restriction on language and year of publication. Case studies, observational studies, and clinical trials reporting hearing loss in adult subjects (>18-60 years of age) of both sexes with DENV, CHIKV, or ZIKV diagnosed by positive molecular/serological examination by RT-PCR or IgM/IgG by ELISA method were included. Results Thirteen studies met the inclusion criteria and were selected for review. The occurrence of auditory symptoms caused by arboviroses and the presence of permanent or transient sensorineural hearing loss was variable in adults. Conclusions Dengue, Chikungunya, and Zika infections in adults are associated with a variety of auditory symptoms. The frequency of permanent or transient sensorineural hearing loss is low but not negligible.

Myringosclerosis in patients with chronic renal failure: comparative analysis with a control group.

UNLABELLED: Myringosclerosis is a scar of the tympanic membrane lamina propria, resulting from trauma or inflammation, characterized by proliferation of collagen, hyalinization, calcium and phosphate deposits and cartilaginous or osseous metaplasia of the middle ear mucosa, a sequence that is similar to that taking place in other types of pathologic calcification, common in chronic renal failure (CRF). AIM: To verify the influence of chronic renal failure on the prevalence of myringosclerosis. METHOD: The otoscopic examination was done in 341 chronic renal failure patients and in 356 normal control individuals. The frequency of positive otoscopies was compared between the two groups, based on individual variables and those pertaining to CRF. RESULTS: 11.7% of the patients had a positive otoscopy in the CRF group, compared to 5.1% in the control group. There was no statistical difference in the frequency of myringosclerosis according to gender, ethnic group, time of dialysis or serum minerals. The groups had a wide age range. CONCLUSION: Although the findings of this study suggest a higher occurrence of myringosclerosis in patients with renal disease, they do not provide a basis for stating that there is any relation between renal failure and tympanic alterations.

DIABETES REMISSION RATE IN DIFFERENT BMI GRADES FOLLOWING ROUX-EN-Y GASTRIC BYPASS.

BACKGROUND: Type 2 diabetes mellitus has a high long-term remission rate after laparoscopic Roux-en-Y gastric bypass (LRYGB), but few studies have analyzed patients with BMI<35 kg/m2. AIM: To compare glycemic control after LRYGB between BMI 30-35 kg/m2 (intervention group or IG) and >35 kg/m2 patients (control group or CG) and to evaluate weight loss, comorbidities and surgical morbidity. METHODS: Sixty-six diabetic patients (30 in IG group and 36 in CG group) were submitted to LRYGB. Data collected annually after surgery were analyzed with generalized estimating equations. RESULTS: Average follow-up was 4.3 years. There was no statistical difference between groups using complete remission American Diabetes Association criteria (OR 2.214, 95%CI 0.800-5.637, p=0.13). There was significant difference between groups using partial remission American Diabetes Association criteria (p=0.002), favouring the CG group (OR 6.392, 95%CI 1.922-21.260). The higher BMI group also had lower HbA1c levels (-0.77%, 95%CI -1.26 to -0.29, p=0.002). There were no significant differences in remission of hypertension, dyslipidemia and surgical morbidity, while weight was better controlled in the IG group. CONCLUSION: No differences were found in diabetes complete remission, although greater partial remission and the lower levels of glycated hemoglobin in the BMI >35 kg/m2 group suggest a better response among more obese diabetic patients with LRYGB. In addition, both groups had important metabolic modifications at the expense of low morbidity.

Descriptive study of goat external and middle ear through computed tomography and endoscopic evaluation, compared with the human ear

Abstract Objective: To describe the external and middle ear of goats, using computed tomography and endoscopic dissection, comparing them with the anatomy of the human ear, aiming to evaluate the viability of this animal model for training in otological endoscopic surgery. Methods: Images of the external and middle ear of goats were produced by computed tomography in the coronal and axial planes and analyzed. The radiological anatomy of the external and middle goat and human ear are described. Some measures of surgical interest were described, such as the length of the external auditory canal, external and internal cross-sectional area of the external auditory canal, middle ear depth, vertical angle of the external auditory canal, length of malleus and incus. After the tomographic study, we analyzed the importance of evaluations through the endoscopic dissection of the goat ear. Results: The bony canal is extremely tortuous and shows a bony prominence with significant elevation near the lower edge of the tympanic membrane. The middle ear has a large tympanic bulla in the hypotympanum region. The malleus is shaped similarly to that of the human, but its handle is located anterior to its head. The mastoid is not pneumatized. Compared to the human mastoid, there was a statistically significant difference in the external and internal cross-sectional area, at the depth of the middle ear, in the vertical angle of the canal and in the length of the incus. Conclusion: Goat morphometric anatomy showed that this model is suitable for surgical simulation in the initial training for endoscopic otological surgery. It is an important contribution to the development of skills to accelerate the subsequent endoscopic otological surgical training in humans, despite some differences found.

Use of nasal mucosa graft in tympanoplasty / Uso do enxerto de mucosa nasal na timpanoplastia

Abstract Introduction Tympanoplasty techniques with different types of graft have been used to close tympanic perforations since the 19th century. Tragal cartilage and temporalis fascia are the most frequently used types of graft. They lead to similar functional and morphological results in most cases. Although little published evidence is present, nasal mucosa has also been shown to be a good alternative graft. Objective Surgical and audiological outcomes at the six-month follow-up in type I tympanoplasty using nasal mucosa and temporalis fascia grafts were analyzed. Methods A total of 40 candidates for type I tympanoplasty were randomly selected and divided into the nasal mucosa and temporalis fascia graft groups with 20 in each group. The assessed parameters included surgical success; the rate of complete closure of tympanic perforation and hearing results; the difference between post- and pre-operative mean quadritonal airway-bone gap, six months after surgery. Results Complete closure of the tympanic perforation was achieved in 17 of 20 patients in both groups. The mean quadritonal airway-bone gap closures were11.9 and 11.1 dB for the nasal mucosa and temporalis fascia groups, respectively. There was no statistically significant difference between the groups. Conclusion The nasal mucosa graft can be considered similar to the temporal fascia when considering the surgical success rate of graft acceptance and ultimate audiological gain.

Resumo Introdução Técnicas de timpanoplastia com diferentes tipos de enxerto têm sido usadas para fechar perfurações timpânicas desde o século XIX. A cartilagem tragal e a fáscia temporal são os tipos de enxerto mais usados, com resultados funcionais e morfológicos semelhantes na maioria dos casos. Embora ainda com poucas evidências publicadas, a mucosa nasal tem se mostrado uma boa opção de enxerto. Objetivo Comparar os resultados cirúrgicos e audiológicos da timpanoplastia tipo I com enxerto de mucosa nasal e de fáscia temporal em seis meses de seguimento. Método Foram selecionados aleatoriamente 40 pacientes candidatos a timpanoplastia tipo I divididos nos grupos enxerto de mucosa nasal e de fáscia temporal com 20 em cada grupo. Os parâmetros avaliados incluíram sucesso cirúrgico, ou seja, a taxa de fechamento completo da perfuração timpânica, e resultados audiológicos; diferença entre o gap quadritonal médio do gap aéreo-ósseo pré e pós-operatório após seis meses da cirurgia. Resultados O fechamento completo da perfuração timpânica foi alcançado em 17 de 20 pacientes no grupo mucosa nasal, como também no grupo fáscia temporal. O ganho quadritonal médio do gap aéreo-ósseo foi de 11,9 dB no grupo mucosa nasal e 11,1 dB no grupo fáscia temporal, respectivamente. Não houve diferença estatisticamente significante entre os grupos. Conclusão O enxerto de mucosa nasal pode ser considerado semelhante ao da fáscia temporal quando se considera o sucesso cirúrgico de pega do enxerto e o ganho audiológico.

Influence of hypercalcemia in the formation of tympanosclerosis in rats.

HYPOTHESIS: Hypercalcemia is thought to perform an important role in the etiopathogenesis of tympanosclerosis. The purpose of the present study was to assess the influence of hypercalcemia in the development of tympanosclerosis in rats with or without acute otitis media. BACKGROUND: The pathogenesis of tympanosclerosis is still unclear. Histologically, it is characterized by a hyaline degeneration in the lamina propria of the middle ear and mastoid mucosa and may lead to a calcification process. The process of calcification is similar to that of other pathologically calcified tissues, such as vessels, heart valves, cornea, and others, which depend on calcium serum levels. METHODS: Twenty-four Wistar rats were divided into two different groups, with one group submitted to hypercalcemia status through calcium diet supplementation and the other used as a control group (normal calcium content diet). Both were submitted to induction of tympanosclerosis by inoculation of Streptococcus pneumoniae on the right middle ear only. Otomicroscopy was conducted every 15 days, and after 7 weeks of inoculation, the animals were killed and the tympanic bullae were resected to be analyzed through light and electron microscopy. RESULTS: The group submitted to hypercalcemia presented a prevalence of tympanosclerosis of 25% against 16.7% in the control group, presenting a relative risk of 1.27 (p=0.72). CONCLUSION: The results suggest that hypercalcemia can have an influence in the development of tympanosclerosis.

Efficacy of functional endoscopic sinus surgery for symptoms in chronic rhinosinusitis with or without polyposis.

UNLABELLED: Functional endoscopic sinus surgery is the preferred treatment for chronic rhinosinusitis currently. Success on symptoms relief and quality of life improvement are the study leading objectives. STUDY DESIGN: retrospective clinical trial. METHODS: Questionnaires were given to the patients referred to Hospital das Clinicas-UFPE to chronic rhinosinusitis (CRS) functional endoscopic sinus intervention during 2003-2004. Symptoms outcome before and after surgery were compared and analyzed using a five-point-ranking scale. RESULTS: Twenty-four patients answered the questions. Eleven patients had CRS and 13 had CRS associated with nasal polypos. Quality of life was restricted by CRS in everyone, with a good improvement in 54,2% cases. All patients could recommend functional endoscopic sinus surgery to someone with same nasal problems and only 3 would not get surgery again. The best symptoms relief results were: nasal obstruction (83,3%), cacosmia/halitosis (80%), hyposmia/anosmia (63,15%), headache (62%). Patients with polyps achieved better symptomatic response than patients with only CRS. CONCLUSIONS: The leading symptoms were improved by functional endoscopic sinus surgery but not so much we expect. Allergic rhinitis presenting, not using nasal spray, poor ambient control influenced this result. Polyps patient achieved better symptoms outcome and quality of life responses on the most of symptoms than CRS patients.

Hearing impairment diagnosis in Pernambuco: services of intermediate complexity--2003.

UNLABELLED: Universal and equal access to health care, granted to the population as of the brazilian constitution of 1988, made it easier the early diagnosis of hearing impairment. Thus, through the sistema único de saúde (sus), public and private health care providers granted this health coverage to the whole brazilian population, in the different levels of complexity. AIM: this paper aims at studying the supply of intermediate complexity hearing impairment diagnosis in pernambuco in the first semester of 2003. MATERIALS AND METHODS: a study of series analyzed 17669 procedures and 372 professionals in the field of hearing impairment in the 185 municipalities in the state of Pernambuco--Brazil--data taken from the outpatient information system of the ministry of health. RESULTS: the results showed that the procedures are being carried out in only five municipalities, most of them managed in municipal units. We also identified an unequal distribution of diagnostic procedures. CONCLUSION: we then concluded that much is still necessary to provide hearing impairment diagnostic in a horizontal fashion, considering the community differences through an universal, integrated and efficient model, as the one proposed by the sistema único de saúde.

Treatment of tympanic membrane perforation using bacterial cellulose: a randomized controlled trial.

INTRODUCTION: Promising treatments for tympanic membrane perforation closure have been studied. Therapies derived from tissue engineering probably eliminate the need for conventional surgery. Bacterial cellulose is presented as an alternative that is safe, biocompatible, and has low toxicity. OBJECTIVES: To investigate the effect on healing of direct application of a bacterial cellulose graft on the tympanic membrane compared to the conventional approach with autologous fascia. METHODS: Randomized controlled trial. Forty patients with tympanic membrane perforations secondary to chronic otitis media were included, and were randomly assigned to an experimental group (20), treated with a bacterial cellulose graft (BC) and control group (20), treated with autologous temporal fascia (fascia). We evaluated the surgical time, hospital stay, time of epithelialization and the rate of tympanic perforation closure. Hospital costs were compared. The statistical significance level accepted was established at p<0.05. RESULTS: The closure of perforations was similar in both groups. The average operation time in the fascia group was 76.50 min versus 14.06 min bacterial cellulose in the group (p=0.0001). The hospital cost by the Brazilian public health system was R$ 600.00 for the bacterial cellulose group, and R$ 7778.00 for the fascia group (p=0.0001). CONCLUSION: Bacterial cellulose grafts promoted the closure of the tympanic membrane perforations, and were demonstrated to be innovative, effective, safe, minimally invasive, efficacious and to have a very low cost.

Otomicroscopic and histologic findings of induced myringosclerosis in rats: a critical study of an experimental model.

UNLABELLED: Myringosclerosis is characterized by hyaline changes of the lamina propria of the tympanic membrane. Experimental studies have used otomicroscopy or histology to evaluate myringosclerosis in animals, but they do not correlate precisely these two methods. AIM: The present study evaluates the accuracy of otomicroscopy in the diagnosis of myringosclerosis in rats. STUDY DESIGN: Experimental. MATERIAL AND METHOD: Myringosclerosis was induced by transtympanic inoculation of Streptococcus pneumoniae in 25 Wistar rats, which were examined weekly through otomicroscopy and sacrificed after eight weeks for histologic study of their tympanic membranes. RESULTS: From the comparison of the otomicroscopic data in relation to the histologic findings, we could observe sensibility of 80% and specificity of 75% for the otomicroscopy. CONCLUSION: Considering the results in this study, otomicroscopy did not represent a good method to evaluate myringosclerosis in this experimental model.

Profile of hospitalizations due to otorhinolaryngologic morbidity requiring surgical treatment. Brazil, 2003.

AIM: To analyze the profile of the surgical procedures related to otorhinolaryngology in Brazil in the year 2003. STUDY DESIGN: This was an observational, descriptive, cross-sectional study. METHODS: We analyzed 80,030 surgical procedures performed in 27 Brazilian States during the period from January to December 2003. The data were obtained from the Hospital Information System of the Ministry of Health. The inclusion factor was a surgical procedure in otorhinolaryngology (ORL). All files were processed with the TABWIN software. RESULTS: In 2003, 80,030 ORL-related surgical procedures were performed in Brazil. The Southeast region had the largest number of procedures (53.08%), followed by the South and Northeast regions (19.6% and 15.6%, respectively). Regarding the group of procedures, surgeries of the pharynx represented 45% of ORL procedures. Procedures of high complexity were more numerous in the ear surgery group. Regarding the distribution of the type of attending institution, the highest concentration of surgical procedures occurred in philanthropic hospitals, followed by state and university public hospitals. The table adopted by SUS for payment of ORL surgical procedures has not been updated for the procedures currently performed, with the consequent inappropriate notification of some types of surgery. CONCLUSION: Knowledge about the profile of surgical hospitalizations related to ORL permits the identification of the peculiarities of the different regions that can help health-managing authorities to make decisions in order to guarantee the principles recommended by SUS regarding access to health services.

The anatomical orientation of the middle turn of the cochlea: importance during surgical implantation of the ossified cochlea.

HYPOTHESIS: The physical relationship between anatomical landmarks such as the tympanic portion of the facial nerve and the orientation of the middle turn of the cochlea are sufficiently constant to provide guidance to surgeons performing cochlear implantation in the ossified cochlea. BACKGROUND: Placing an implant in an ossified cochlea is technically difficult. The surgeon needs to drill two tunnels through the promontory bone to insert electrode arrays in the region of the basal and middle turns of the cochlea. However, few studies describe the orientation of these tunnels or how to use anatomical landmarks to guide the surgeon during their creation. This problem is particularly true for the superior (middle turn) tunnel. DESIGN: Twenty human temporal bones from adult cadavers were analyzed. They were dissected with exposure of all middle ear structures, followed by the removal of the tympanic ring, tympanic membrane, malleus, and incus. We measured the angle between the tympanic segment of the fallopian canal and a line passing through the lower portion of the middle turn of the cochlea. RESULTS: The measured angles varied from 123 and 152 degrees with an average of 133.85 degrees and the standard deviation of ± 6.83 degrees. CONCLUSION: The tunnel for the middle turn should be created with an inclination of about 134 degrees in relation to the tympanic segment of the facial nerve.