Endoscopic diving technique for hearing preservation in managing labyrinth-invading cholesteatomas.

PURPOSE: Complete removal of the matrix over the existing fistula in the event of an extensive cholesteatoma with labyrinth invasion can result in total deafness. This study aimed to present a novel method of underwater endoscopic labyrinth dissection using continuous steroid irrigation (CSI) and systemic steroid administration for hearing preservation. METHODS: The endoscopic diving technique (EDT) was used to dissect semicircular canals, revealing the underwater anatomy of membranous labyrinth structures, in two cadaver temporal bones. EDT with CSI was used in three clinical cases with extensive cholesteatoma. RESULTS: On cadaver temporal bones, the anatomy of the lateral (LSC), superior (SSC), and posterior membranous semicircular canals with their respective ampullas and common crus was documented. In the first case managed with transcanal EDT, the LSC was eroded across almost its entire length. The fallopian canal was circumferentially eroded at the second genu and part of the mastoid segment. The cholesteatoma matrix was completely removed, and the membranous LSC was preserved. In the second and third cases, we were able to remove the cholesteatoma matrix along the eroded bony semicircular canals while keeping the membranes intact. No sensorineural hearing loss was detected in the postoperative masked pure-tone audiometry at a mean follow-up time of 12 months or cholesteatoma recurrence at the follow-up imaging. CONCLUSIONS: EDT with CSI can be safely utilized in the course of temporal bone labyrinth dissections and provides advantages during cholesteatoma removal over the eroded labyrinth on preservation of the membranous structures, and thus may help preserve cochlear function.

Purely Endonasal Endoscopic Approaches for Extracranial Trigeminal Nerve Schwannoma.

OBJECTIVE: The aim of this study is to assess the effectiveness and safety of purely endonasal endoscopic resection of extracranial trigeminal schwannomas (TGSs), with assessment of surgical and clinical outcomes in order to identify optimal candidates for an endonasal endoscopic approach (EEA). METHODS: A retrospective review of patient's records operated for TGSs between 2008 and 2021 was conducted. Patients operated with a purely EEA were included in this study. Pictures from a frozen fresh cadaver head dissection were used to demonstrate the surgical approach and to show anatomic relationships, complexity of the surgical area and safe corridors for surgery. RESULTS: A total of 5 patients (4 females and 1 male) were operated for TGS. All patients had facial numbness (100%) as a presenting symptom, followed by facial pain in 2 patients (40%), and orbital pain in 1 (20%). Also, 3 patients (60%) had a tumor originating at the level of the foramen ovale and 2 (40%) at the foramen rotundum. The mean tumor diameter was 3,7 ± 2 cm. Gross total resection were achieved in all cases. Postoperatively, 1 patient had severe mastication problems, 1 had blurred vision, and in the long-term follow-up, 1 had frontal sinusitis. The mean follow up was 106.6 (min:49, max:132, SD: 29.82) months. No recurrences were detected. CONCLUSIONS: In cases with the extradural TGS having limited extension into Posterior Cranial Fossa, or located in the Middle Cranial Fossa, a purely EEA is possible even for tumors bigger in size. Unilateral endonasal corridors are adequate for resection in most cases.

Efficiency of resveratrol in the prevention and treatment of age-related hearing loss.

Age-related hearing loss (ARHL) is a major public health concern, which is characterized by gradual, progressive sensorineural hearing loss and deterioration of sound localization, with no effective treatment available to date. The aim of the present study was to evaluate the efficacy of resveratrol to prevent and treat ARHL. For this purpose, 32 male C57BL/6 mice were assigned to four groups: Early treatment, late treatment, control and sham control. The experiment lasted for 15 months. Treatment was started at three months of age in the early treatment group and at sixth months in the late treatment group. The auditory brainstem response test was performed once every three months. At the end of the study period, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, NF-κB, Bcl-2, Bcl-xL, Bax, Bcl-2 homologous antagonist/killer (Bak), caspase-3 and caspase-9 levels in the cochlear tissues of the animals were analyzed by reverse transcription-quantitative PCR. Hearing thresholds of the mice in the early treatment group were better than those in the other groups (P<0.001) at the end of the study. However, hearing levels in the late treatment group were not significantly different from those in the control groups (P>0.05), although mean thresholds were lower. The threshold shift in the early treatment group was significantly lower at all frequencies when compared with those in the control groups (P<0.001). The mRNA expression levels of pro-apoptotic genes Bax and Bak were lower (P<0.05), anti-apoptotic genes Bcl-2 and Bcl-xL were higher (P<0.05), NF-κB, COX-2 and iNOS as genes that have a role in inflammation and caspase-3 and caspase-9 as genes with a vital role in apoptosis were lower (P<0.05) in the early treatment group when compared with the late treatment and control groups. These results suggested that resveratrol is effective in the prevention of ARHL, particularly when started prior to the beginning of hearing loss.

Preference and Perception of Enhanced Images During Endonasal Endoscopic Surgery.

Image enhancement is used widely in endoscopic sinonasal surgery. It is yet to be established whether image enhancement has advantages over white-light endoscopy. The authors aimed to evaluate the preferences and subjective visual perception of image enhancement in diagnostic images acquired at the beginning of endonasal endoscopic surgeries. An online survey consisting of 12 endoscopic images, 4 enhanced with Clara mode, 4 enhanced with Chroma mode, and 4 enhanced with Clara+Chroma mode, was distributed. The enhanced images were randomly presented with nonenhanced white-light images. These images were captured at the beginning of endonasal endoscopic surgeries for septal perforation, septal deviation, and chronic rhinosinusitis. Survey respondents (n = 205) included 81 otorhinolaryngologists, 94 other specialty physicians (35 endoscopy/laparoscopy users and 59 nonusers), and 30 nonmedical image experts. They were asked to choose superior images according to brightness, contrast and sharpness, depth of field, and overall preference. A quantitative study was also conducted to evaluate different enhancement modes. The authors found that Clara enhanced brightness and Chroma enhanced contrast and sharpness significantly (P < 0.001). Overall, 91.8% chose Clara and 91.7% chose Clara+Chroma-enhanced images for brightness enhancement. For contrast and sharpness, 87% chose Clara+Chroma and 86.7% chose Chroma. There was no significant difference between perception scores among the groups. Our survey group showed a significantly high overall preference for enhanced images. This preference was independent of profession or experience, but closely related to the quantitative enhancement of the specific mode. Continuous use of image enhancement in endonasal surgery may have advantages over white-light endoscopy.

Titanium incus interposition ossiculoplasty: audiological outcomes and extrusion rates.

This study aimed to evaluate the benefit but also the extrusions, dislocations, and failures of a titanium incus prosthesis along with the long-term audiological outcomes. We prospectively collected data from 139 patients undergoing ossiculoplasty using the Fisch titanium incus prosthesis between 2001 and 2016. Overall, 126 patients with at least 6 months of follow-up (mean 4.5 years, range 6-155 months) were analyzed. Patients were grouped as "extrusion" (n = 9, 7%) if the prosthesis extruded, "failure" (n = 22, 18%) if a reoperation was needed concerning the prosthesis, and "stable" (n = 95, 75%) if the prosthesis remained functional in the middle ear. Mean postoperative air bone gaps (ABG) for 0.5-3 kHz for the overall group and the stable group were 19.8 (±11.9) and 15.3 (±7.5), respectively. Long-term results of stable group revealed an ABG (0.5-3 kHz) below 10 dB in 25% and below 20 dB in 81% of the patients. Atelectasis was the most frequent cause of extrusion, which occurred after a mean time of 28.7 months (range 15-48 months). Mean timing for reoperation was 30.7 months (range 5-131 months) in the failure group. There was no significant difference in mean postoperative ABG among patients with or without cholesteatoma, primary or staged ossiculoplasty in cholesteatoma, presence or absence of malleus head at the time of ossiculoplasty, open or closed cavity surgeries, or the degree of pneumatization of the temporal bone. The Fisch titanium incus prosthesis is a reliable alternative to using autologous incus for interposition ossiculoplasty, with similar hearing outcomes. Using this prosthesis, a 15 dB ABG should be expected.

Retroauricular Approach for Targeted Cochlear Therapy Experiments in Wistar Albino Rats.

BACKGROUND: As the idea of stem cell technology in the treatment of sensorial hearing loss has emerged over the past decades, the need for in vivo models for related experiments has become explicit. One of the most common experimental models for inner ear stem cell delivery experiments is the Wistar albino rat. AIMS: To investigate the surgical anatomy of the temporal bone of the Wistar albino rat with respect to the dissection steps, operative techniques and potential pitfalls of surgery. STUDY DESIGN: Animal experimentation. METHODS: Adult Wistar albino rats were operated on via the retroauricular approach under an operation microscope. The anatomy of the temporal bone, the surgical route to the temporal bulla and the inner ear were investigated. Technical details of surgical steps, complications and potential pitfalls during the surgery were noted. RESULTS: The study group consisted of 40 adult Wistar albino rats. The mean times to reach the bulla and to achieve cochleostomy were 4.3 (2-13 min) and 7.5 min (3.5-22 min), respectively. The mean width of the facial nerve was 0.84 mm (0.42-1.25 mm). The stapedial artery lay nearly perpendicular to the course of the facial nerve (88-93 °C). There were three major complications: two large cochleostomies and one massive bleed from the stapedial artery. CONCLUSION: The facial nerve was the key anatomical landmark in locating the bulla. By retrograde tracing of the facial nerve, it was possible to find the bulla ventral (inferior) to the main trunk. The facial nerve trunk was the upper limit when drilling the bulla. By dissecting the main trunk of the facial nerve and retracting cranially, a large drilling space could be achieved. Our results suggest that the retroauricular approach is an effective, feasible route for inner ear drug delivery experiments in Wistar albino rats.

Study of mouse induced pluripotent stem cell transplantation intoWistar albino rat cochleae after hair cell damage.

BACKGROUND/AIM: As the regeneration capacity of hair cells is limited, inner ear stem cell therapies hold promise. Effects of mouse induced pluripotent stem cells (IPSCs) on Wistar albino rats (WARs) with hearing impairment were investigated. MATERIALS AND METHODS: Thirty-five adult WARs with normal hearing were divided into 4 groups. Excluding the study group (n = 15), the other three groups served as control groups for ototoxicity and IPSC injection models. IPSC injections were performed via cochleostomy after a retroauricular approach. Auditory functions were evaluated with auditory brainstem responses (ABRs) before and after the injections. After a final hearing assessment the WARs were sacrificed and cochleae were extracted to see the biologic behavior of IPSCs in the inner ear by light microscopy and immunohistochemistry. RESULTS: There were no significant differences in the click-ABR thresholds in the study group after IPSC transplantation. The mean hearing threshold in the study group after ototoxic agent injection was 53.2 dB (10-90 dB). There was no significant difference between groups (P > 0.05) and no differentiated stem cells were observed immunohistochemically. CONCLUSION: Transplanted IPSCs did not show a therapeutic effect in this trial. We discuss potential pitfalls and factors affecting the therapeutic effect.

Does Dehiscence of the Facial Nerve Canal Affect Tympanoplasty Results?

This study aimed to evaluate the prevalence of facial nerve canal dehiscence in tympanoplasty patients and its influence on the need for revision surgery and on hearing results and anatomical outcomes. Patients who underwent tympanoplasty with/without mastoidectomy at Ankara University Otolaryngology Department from 2006 through 2013 with a minimum follow-up period of 6 months were reviewed retrospectively in this original study. Patients were divided into those with and without cholesteatoma. Numbers and frequencies of dehiscence were recorded according to disease type, the need for revision surgery, and hearing results and anatomical outcomes. Study subjects included 206 patients, of whom 15 (7.3%) had dehiscence. The prevalence of dehiscence was significantly high in the patients with cholesteatoma (13/50 patients) compared with those without (2/156 patients). The dehiscence frequency was significantly high in cholesteatoma (42.8%), as well as overall (14.7%), revision-surgery patients. Hearing results (P < 0.05) and anatomical outcomes were better in patients without dehiscence. Dehiscence is more common in patients with than without cholesteatoma and negatively affects tympanoplasty outcomes, including hearing results, anatomical outcomes, and the need for revision surgery.

An unusual entry site for a nasal foreign body: a neglected trauma patient.

Foreign body (FB) in the nose is a frequent situation seen generally among children. A variety of objects left in different sites of the nose has been reported in the literature. Insertion of a FB to the nose is generally via the anterior nares. In this report, an unusual entry site for a nasal FB in a neglected trauma patient is presented. FB should be suspected and investigated in children after penetrating facial injury.