Otology & Neurotology最新文献

Objective: To evaluate semicircular canal function using video head impulse test (vHIT) in relapsing polychondritis (RP) patients presenting with dizziness and sensorineural hearing loss.

Study design: Retrospective case review.

Setting: Tertiary referral center.

Patients: Three patients with RP underwent vHIT and hearing tests.

Intervention: Diagnostic.

Main outcome measures: The gain in vestibulo-ocular reflex (VOR) and the presence of catch-up saccade were examined, and the correlation between semicircular canal dysfunction and hearing loss was investigated.

Results: Of the six ears, five exhibited semicircular canal dysfunction. Among these, one ear showed dysfunction in two semicircular canals, while the remaining four ears demonstrated dysfunction in all three semicircular canals. Sensorineural hearing loss, ranging from moderate to profound, was detected by pure-tone audiometry in all six ears. Furthermore, a significant correlation was observed between VOR gain in the horizontal semicircular canal (HSC) and hearing level.

Conclusions: This study demonstrated semicircular canal dysfunction in RP patients presenting with dizziness and hearing loss using vHIT. Moreover, a significant correlation was found between HSC dysfunction and the severity of hearing loss. While inner ear involvement is a key clinical symptom included in the diagnostic criteria for RP, there have been few reports evaluating vestibular dysfunction, and this is the first report on the evaluation of several cases using vHIT. Accurate assessment of vestibular function by vHIT may facilitate early diagnosis and intervention in RP, potentially improving patient outcomes.

Objective: To evaluate if permanent hearing loss occurred in the unoperated ear of patients undergoing otologic and skull base surgery with high-speed otologic drilling.

Study design: We retrospectively studied 250 patients (mean age 57.8 yr; 120 males, and 130 females) undergoing otologic or skull base surgery with high-speed drilling between 2013 and 2019.

Setting: The University of Pittsburgh Medical Center.

Patients: We evaluated preoperative and postoperative audiograms for patients undergoing surgery for cochlear implantation (95 patients, 38.0%), cholesteatoma or chronic ear disease (88 patients, 35.2%), repair of lateral skull base encephalocele (26 patients, 10.4%), resection of vestibular schwannoma or meningioma of the cerebellopontine angle (23 patients, 9.2%), lateral temporal bone resection (8 patients, 3.2%), microvascular decompression (7 patients, 2.8%), or other operations involving a high-speed otologic drill (3 patients, 1.2%).

Main outcome measures: Hearing threshold shift, measured as the difference between postoperative threshold and preoperative threshold for each frequency. The association of age, gender, tested frequency, and surgery type with hearing threshold shift was investigated with analysis of covariance.

Results: A total of 102 patients (40.8%) had a 10-dB or greater worsening of their hearing in at least one frequency on their postoperative audiogram in the contralateral, unoperated ear. One hundred six subjects (42.4%) had no change in hearing of 10 dB or greater at any frequency. Among patients with longitudinal postoperative audiograms, accelerated age-related hearing loss was observed in low frequencies.

Conclusions: A significant number of patients demonstrated poorer hearing thresholds in the contralateral, unoperated ear after otologic and skull base surgery.

Hypothesis: This study investigates the impact of different diffusion magnetic imaging (dMRI) acquisition settings and mathematical fiber models on tractography performance for depicting cranial nerve (CN) VII in healthy young adults.

Background: The aim of this study is to optimize visualization of CN VII for preoperative assessment in surgeries near the nerve in the cerebellopontine angle, reducing surgery-associated complications. The study analyzes 100 CN VII in dMRI images from the Human Connectome Project, using three separate sets with different b values ( b = 1,000 s/mm 2 , b =2,000 s/mm 2 , b =3,000 s/mm 2 ) and four different tractography methods, resulting in 1,200 tractographies analyzed.

Results: The results show that multifiber and free water (FW) compartment models produce significantly more streamlines than single-fiber tractography. The addition of an FW compartment significantly increases the mean streamline fractional anisotropy (FA). Expert quality ratings showed that the highest rated tractography was the 1 tensor (1T) method without FW at b values of 1,000 s/mm2.

Conclusions: In this young and healthy cohort, best tractography results are obtained by using a 1T model without a FW compartment in b =1,000 diffusion MR images. The FW compartment increased the contrast between streamlines and cerebrospinal fluid (higher mean streamline FA). This finding may help ongoing research to improve CN VII tractography results in tumor cases where the nerve is often stretched and thinned by the tumor.

Objective: To evaluate tympanic membrane regeneration therapy (TMRT) for pediatric tympanic membrane perforations (TMPs).

Study design: Intervention study.

Setting: Research institute hospital.

Patients: In this study, 20 patients with chronic TMP (M/F: 13/7, 13/8 ears, age 0-15 years) treated with TMRT were evaluated. As comparison, 20 pediatric patients with chronic TMP who underwent myringoplasty/tympanoplasty were included.

Interventions: For the TM repair procedure, the edge of the TMP was disrupted mechanically, and gelatin sponge immersed in basic fibroblast growth factor was placed inside and outside the tympanic cavity and covered with fibrin glue. The TMP was examined 4 ± 1 weeks later. The protocol was repeated up to four times until closure was complete.

Main outcome measures: Closure of the TMP and hearing improvement were evaluated at 16 weeks after the final regenerative procedure. Adverse events were monitored.

Results: The mean follow-up period was 427.1 days. The TM regenerated in all cases, but pinhole reperforation occurred in two cases, and the final closure rate was 90.5% (19 of 21). Hearing improved to 24.9 ± 7.6 dB on average before surgery and to 13.8 ± 5.4 dB after surgery. The AB gap improved from 12.9 ± 8.0 to 5.2 ± 3.5 dB.The myringoplasty/tympanoplasty group had significantly lower AB gap improvement compared with the TMRT group. There were no adverse events.

Conclusions: TMRT can be expected to regenerate near-normal TMs with a high closure ratio, resulting in better-hearing improvement compared with the myringoplasty/tympanoplasty group, and is an effective treatment for children with long life expectancy.

Objective: The management options for small acoustic tumors are still controversial, and surgery is indicated in a select number of patients only. This is to avoid unnecessary extensive operations and risk of complications. Endoscopic transcanal approach, which was recently introduced, can be an alternative option to overcome these challenges. We have developed a modified technique for endoscopic transcanal removal of small acoustic tumors with tympanoplasty using tragal cartilage and without the need to harvest abdominal fat for obliteration. There was also no need to do an ear cul-de-sac procedure compared with the previous method. We report the long-term outcomes of this approach.

Study design: Retrospective review.

Setting: Tertiary hospital.

Patients: Those who were diagnosed with small acoustic tumors between June 2016 and June 2022 were enrolled.

Interventions: Tumor removal via a Modified Endoscopic Transcanal Transpromontorial Approach (mETTA).

Main outcome measure: Tumor control rate, closure rate of tympanic membrane, and complications such as cerebrospinal fluid (CSF) leakage and facial palsy were analyzed. Operation time and hospital stay were also analyzed.

Results: Twenty-two patients with a mean age of 55.5 ± 9.4 years were enrolled. Eighteen were vestibular schwannomas (VS), two were intracochlear schwannomas (ICS), and two were with intravestibulocochlear schwannomas (IVCS). Gross total removal was achieved in 21 cases. One had developed significant CSF leakage, and the other patient complicated with permanent facial palsy. The tympanic membrane healed well in all patients, but three patients showed delayed healing until several months and treated conservatively. Mean operation time was 149.6 ± 48.4 minutes, mean hospital stay was 8.9 ± 4.5 days, and mean postoperative follow-up period was 42.0 ± 15.7 months.

Conclusion: Long-term results of modified endoscopic transcanal approach to small acoustic tumors are acceptable and comparable to classical treatments such as translabyrinthine approach or gamma knife radiation. This is an alternative option for smaller tumors warranting surgical removal and maintained cosmetic advantages.

Objective: To discuss the potential benefit of belzutifan therapy in a patient with von Hippel-Lindau (VHL) disease-associated endolymphatic sac tumor (ELST).

Patients: Case report.

Interventions: Clinical details of a patient with residual ELST after hearing preservation surgery who initiated belzutifan therapy postoperatively for concurrent renal cell carcinoma, as well as literature review of belzutifan and ELST.

Main outcome measures: The patient remained without radiologic evidence of growth of her residual tumor at 17 months post-initiation of belzutifan. It is unknown whether this represents therapeutic drug effect, nonviability of residual tumor, or slow tumor growth not captured radiographically within the duration of follow-up.

Conclusions: Belzutifan could have direct therapeutic benefit in patients with VHL-associated ELST.

Hypothesis: Microneedle-mediated intracochlear injection of siRNA-Lipofectamine through the round window membrane (RWM) can be used to transfect cells within the cochlea.

Background: Our laboratory has developed 100-μm diameter hollow microneedles for intracochlear injection through the guinea pig RWM. In this study, we test the feasibility of microneedle-mediated injection of siRNA and Lipofectamine, a commonly used reagent with known cellular toxicity, through the RWM for cochlear transfection.

Methods: Fluorescently labeled scramble siRNA was diluted into Lipofectamine RNAiMax and OptiMEM. One microliter of 5 μM siRNA was injected through the RWM of Hartley guinea pigs at a rate of 1 μl/min (n = 22). In a control group, 1.0 μl of Lipofectamine, with no siRNA, was diluted into OptiMEM and injected in a similar fashion (n = 5). Hearing tests were performed before and either at 24 hours, 48 hours, or 5 days after injection. Afterward, animals were euthanized, and cochleae were harvested for imaging. Control cochleae were processed in parallel to untreated guinea pigs.

Results: Fluorescence, indicating successful transfection, was observed within the basal and middle turns of the cochlea with limited distribution in the apex at 24 and 48 hours. Signal was most intense in the organ of Corti, spiral ligament, and spiral ganglion. Little to no fluorescence was observed at 5 days post-injection. No significant changes in auditory brainstem response (ABR) were noted post-perforation at 5 days, suggesting that siRNA-Lipofectamine at low doses does not cause cochlear toxicity.

Conclusions: Small volumes of siRNA and Lipofectamine can be effectively delivered to cochlear structures using microneedles, paving the way for atraumatic cochlear gene therapy.

Objective: To characterize transimpedance matrix (TIM) heatmap patterns in patients at risk of labyrinthine abnormality to better understand accuracy and possible TIM limitations.

Study design: Retrospective review of TIM patterns, preoperative, and postoperative imaging.

Setting: Tertiary referral center.

Patients: Patients undergoing cochlear implantation with risk of labyrinthine abnormality.

Intervention: None.

Results: Seventy-seven patients were evaluated. Twenty-five percent (n = 19) of patients had a TIM pattern variant identified. These variants were separated into 10 novel categories. Overall, 9% (n = 6) of electrodes were malpositioned on intraoperative x-ray, of which 50% (n = 3) were underinserted, 17% (n = 1) were overinserted, 17% (n = 1) had a tip foldover, and 17% (n = 1) had a coiled electrode. The number of patients with a variant TIM pattern and normal x-ray was 18% (n = 14), and the number of patients with normal TIM pattern and malposition noted on x-ray was 3% (n = 2; both were electrode underinsertions that were recognized due to open circuits and surgical visualization).A newly defined skip heat pattern was identified in patients with IP2/Mondini malformation and interscalar septum width <0.5 mm at the cochlear pars ascendens of the basal turn.

Conclusions: This study defines novel patterns for TIM heatmap characterization to facilitate collaborative and comparative research moving forward. In doing so, it highlights a new pattern termed skip heat, which corresponds with a deficient interscalar septum of the cochlea pars ascendens of the basal turn in patients with IP2 malformation. Overall, the data assist the surgeon in better understanding the implications and limitations of TIM patterns within groups of patients with risk of labyrinthine abnormalities.