Introduction: In morphologically normal-appearing inner ears, measurements of the distance between the round window and carotid canal (RCD), the maximum diameter of the basal turn of the cochlea next to the round window (BD), and the thickness of the promontory (PT) just lateral to the basal turn may be used as guide for safe cochleostomy and implant placement. Materials and Methods: From January to March 2022, a cross-sectional observational study was carried out in a tertiary care hospital. The round window to carotid canal distance (RCD), the largest diameter of the cochlea's basal turn next to the round window (BD), and the thickness of the promontory immediately lateral to the basal turn (PT) were measured using CT temporal bone images of 150 persons without cochlear abnormalities. The values obtained were compared using Paired T-test for significance of difference between both genders and sides. Results: A total of 150 participants—, 75 men and 75 women—, with a mean age of 37. 5 years were enrolled in the study. With a range of 7. 18 mm to 10. 52 mm, the mean RCD was 8. 84 mm (SD 0. 8 mm). The mean BD was 2. 27 mm (SD 0. 4 mm), while the mean PT was 1. 15 mm (SD 0. mm). The values obtained did not differ significantly in both the genders and the right and left sides (p = 0. 37 and 0. 24, respectively). Conclusion: The present study has defined and calculated pertinent measures at cochleostomy site that will aid safe electrode insertion and prevent misplacement.

Introduction: Cochlear implantation (CI) is now regarded as a standard treatment for children with severe to profound sensor neural hearing loss. This study aimed to compare the efficacy of the round window approach (RWA) and standard cochleostomy approach (SCA) in the preservation of residual hearing after CI in pediatric patients. Materials and Methods: This double-blind randomized controlled trial was conducted on 97 pediatric patients receiving CI with 12-month follow-up. The study population was divided into two groups according to the surgical approaches they received, including RWA and SCA. Consequently, the patients were evaluated based on the Categories of Auditory Performance scale (CAP) and Speech Intelligibility Rating (SIR) test 45-60 days and 3, 6, 9, and 12 months post-surgery. Results: The CAP and SIR mean scores increased in both groups during the 12-month follow-up. This upward trend was significant in both groups (P<0. 001). There was no significant difference between the two treatment groups in any of the follow-up stages regarding the CAP mean score. The mean SIR score (P=1. 14± 0. 40) was significantly higher in the RWA group 3(P=0. 001), 6(P=0. 008), and 9(P=0. 006) months after the surgery. However, there was no significant difference between the RWA and SCA groups, regarding 1-year SIR (P=0. 258). Conclusion: The CI with either RWA or SCA could improve hearing and speech performance in pediatric patients. Although mid-term speech intelligibility was better for RWA, there was no significant difference in the 1-year outcome between these two methods.

Background: Cochlear implantation (CI) is usually performed through mastoidectomy and posterior tympanotomy (PT) to access the cochlea. This surgical procedure can expose the surgeon to possible complications or misplacement of the electrode. Alternative techniques for cochlear implantation with endomeatal or suprameatal approach without posterior tympanotomy have been described. Here, we report a 4-year-old patient, a candidate for cochlear implantation, for whom due to the difficulty of accessing the round window, we used the combined approach to reach the cochlea. Case Report: In this particular patient, there was no restriction on mastoid pneumatization,so, we began surgery with a posterior tympanotomy approach to access the round window. But after opening the mastoid and facial recess, because the lateral semicircular canal was not developed well, the oval window and the stapes were displaced posteriorly. Moreover, because of posterior displacement, the round window was not visible through the facial recess. Therefore, by adding the trans-canal approach, we could access the round window, and the prosthesis was successfully inserted. No complication occurred, and six months after surgery, the patient had acceptable auditory and speech performances. Conclusion: Familiarity and having experience in different approaches to the cochlea is a prerequisite for a cochlear implant surgeon to be able to use alternative methods in cases of difficulty in accessing the round window or finding a proper site for cochleostomy.

Background: Noise-induced hearing loss (NIHL) is caused by chronic exposure to high-intensity sound. Although noise hazard has been extensively studied in the past decades, cochlear implants and hearing aids are only safe and clinically effective intervention in hearing-impaired person. In recent years, stem cell therapy has been studied to repair damaged inner ear tissue including hair cells and spiral ganglion neurons (SGNs). Because of small size and complex structure of the cochlea, it is difficult to transplant stem cells. It is necessary,stem cell injection procedure has a minimal adverse effect on target tissue. Cochleostomy are currently used to inject stem cells that can impair hearing. In addition, cell viability is an essential factor in the regeneration of damaged hair cells. Aim: The aim of this study was to examine the survival of bone marrow mesenchymal stem cells (BMSCs) injected through the round window of the NIHL rat model. Methods: Adult male rats were exposed to the 110 dB white noise paradigm for 6 hours in 5 days to induce deafness. Distortion-product otoacoustic emission (DPOAE) was recorded before and after noise exposure. Hoechst labeled-cells were transplanted into the rat cochlea through the round window. Hoechst-labelled MSCs were assayed in the endolymph for 24h, 72h, seven and 10 days after injection. Results: Our findings revealed that stem cell transplantation into the cochlea via round window niche is a safe surgical approach. As well, cells transplanted into the endolymph survived for a postoperative period of at least 1 week. Conclusion: BMSC can survive at least one week in adult rat cochlea after injection through the round window niche.

Background: Intra-arterial thrombectomy (IAT) is one of the mainstream treatments for acute ischemic stroke. As relatively little evidence on extracranial internal carotid artery (ICA) occlusions exists in the literature, we share our experiences after using IAT for intracranial and extracranial ICA occlusions. We further clarify the imaging characteristics of multiphase computed tomography angiography (CTA) and share the experience of balloon angioplasty in acute ICA occlusion. Objectives: To investigate the imaging findings of multiphase CTA and the clinical conditions and outcomes of acute ICA occlusions at different segments after IAT. Patients and Methods: All participants receiving IAT for acute stroke with isolated ICA occlusions were included, obtained from three hospitals between June 2016 and November 2018. An imaging review for non-enhanced computed tomography (CT), multiphase CTA, and angiography was conducted. Epidemiological and clinical data were reviewed. Further comparisons were evaluated between the occlusion side from the C6 to C7 segments and C1 to C5 segments of the ICA. Results: The average age of the patients was 73. 0 years, and the initial National Institutes of Health Stroke scale (NIHSS) score was 18. 6. Nineteen percent of cases had good outcomes. Good reperfusion results were achieved in 50% of cases. Compared to the group with occlusion from C6-C7, the group with occlusion from C1-C5 had a relatively good Alberta Stroke Program Early CT score (ASPECTS) in the A1 phase of the multiphase CTA, and more patients had a good collateral. Three cases received a balloon angioplasty for a concurrent proximal cervical ICA tight stenosis, and all cases had good reperfusion results. Conclusion: Distal occlusion of the ICA demonstrates lower ASPECTS and a worse collateral on multiphase CTA. A multiphase CTA with an extended scan range in the A2 and A3 phases is able to exclude pseudo-occlusion of the ICA. Balloon angioplasty is helpful for concurrent proximal cervical ICA tight stenosis.