Cochlear implant insertion should be as least traumatic as possible in order to reduce trauma to the cochlear sensory structures. The force applied to the cochlea during array insertion should be controlled to limit insertion-related damage. The relationship between insertion force and histological traumatism remains to be demonstrated. Twelve freshly frozen cadaveric temporal bones were implanted with a long straight electrodes array through an anterior extended round window insertion using a motorized insertion tool with real-time measurement of the insertion force. Anatomical parameters, measured on a pre-implantation cone beam CT scan, position of the array and force metrics were correlated with post-implantation scanning electron microscopy images and histological damage assessment. An atraumatic insertion occurred in six cochleae, a translocation in five cochleae and a basilar membrane rupture in one cochlea. The translocation always occurred in the 150- to 180-degree region. In the case of traumatic insertion, different force profiles were observed with a more irregular curve arising from the presence of an early peak force (30 ± 18.2 mN). This corresponded approximately to the first point of contact of the array with the lateral wall of the cochlea. Atraumatic and traumatic insertions had significantly different force values at the same depth of insertion (p < 0.001, two-way ANOVA), and significantly different regression lines (y = 1.34x + 0.7 for atraumatic and y = 3.37x + 0.84 for traumatic insertion, p < 0.001, ANCOVA). In the present study, the insertion force was correlated with the intracochlear trauma. The 150- to 180-degree region represented the area at risk for scalar translocation for this straight electrodes array. Insertion force curves with different sets of values were identified for traumatic and atraumatic insertions; these values should be considered during motorized insertion of an implant so as to be able to modify the insertion parameters (e.g axis of insertion) and facilitate preservation of endocochlear structures.
Objectives: The aim of the study was to evaluate the sleep architecture and its possible alterations in chronic tinnitus patients, and investigate any possible correlation between sleep architecture modifications and tinnitus perception, adaptation, and the degree of discomfort in these patients. Design: In a prospective, case-control, nonrandomized study, 18 patients affected by chronic tinnitus were compared with a homogeneous control group consisting of 15 healthy subjects. The experimental group was enrolled at the Tinnitus ambulatory at Policlinico Umberto I Department of Sensory Organs, and the control group was composed of voluntary subjects. A full overnight polysomnography was performed on both groups. Tinnitus patients answered two questionnaires: the tinnitus handicap inventory (THI) and a questionnaire concerning their subjective sleep quality, tinnitus intensity before bedtime, tinnitus intensity at remembered nocturnal wake-up periods, and tinnitus intensity at morning wake-up. Controls completed only the sleep quality questionnaire. Results: All tinnitus patients had a statistically significant alteration in sleep stages. Average percentage of stage 1 + stage 2 was 85.4% ± 6.3, whereas, in the control group, the average percentage of stage 1 + stage 2 was 54.9 ± 11.2 (p < 0.001). Stages 3 and 4 and rapid eye movement (REM) sleep was lacking in all tinnitus patients with an average percentage of 6.4 ± 4.9 of REM sleep, and 6.4 ± 4.9 of stages 3 + 4. The control group showed an average percentage of 21.5 ± 3.6 of REM sleep and 21.5 ± 3.6 of stages 3 + 4 (p < 0.001). No correlation was found between the decrease of REM and the increase of the THI score in the tinnitus group (r = 0.04). However, a mild correlation was found between the increase of light sleep (stage 1 + stage 2) and the THI score reported by the tinnitus group. Therefore, patients with light sleep report a higher THI score (r = 0.4). Conclusions: The significant alteration of sleep parameters assessed in tinnitus patients underlines the necessity to consider an adequate therapy that could improve patients’ sleep quality and also opens avenues for further investigations.
Introduction: The aim of the current systematic review is to update the pooled survival outcome of patients with T2 glottic carcinoma treated with either laser surgery (CO2 transoral laser microsurgery [CO2 TOLMS]), radiotherapy (RT), or open partial laryngectomy (OPL). Methods: A systematic search was performed using the MEDLINE database, Scopus, and Google scholar. The inclusion criteria were studies of patients with T2N0 glottic tumor, treated with either primary CO2 TOLMS, definitive curative RT, or primary OPL, and with reported oncological outcome at 5 years calculated with a Kaplan-Meier or Cox regression method. Results: The results of the current review show that local control (LC) is higher with OPL 94.4%, while there are no differences in LC at 5-year posttreatment for patients treated with RT, compared to those treated with CO2 TOLMS (respectively, 75.6% and 75.4%). Primary treatment with OPL and CO2 TOLMS results in higher laryngeal preservation than primary treatment with RT (respectively 95.8%, 86.9%, and 82.4%). Conclusion: First-line treatment with OPL and CO2 TOLMS should be encouraged in selected T2 patients, because it results in higher laryngeal preservation and similar LC compared to primary treatment with RT. The involvement of the anterior commissure in the craniocaudal plane and T2b impaired vocal cord mobility have a poorer prognosis and LC compared to patients with T2a tumors for both CO2 TOLMS and RT.