Abstract
Blast exposure can induce various types of hearing impairment, including permanent hearing loss, tinnitus, and hyperacusis. Herein, we conducted a detailed investigation of the cochlear ...pathophysiology in blast-induced hearing loss in mice using two blasts with different characteristics: a low-frequency dominant blast generated by a shock tube and a high-frequency dominant shock wave generated by laser irradiation (laser-induced shock wave). The pattern of sensorineural hearing loss (SNHL) was low-frequency- and high-frequency-dominant in response to the low- and high-frequency blasts, respectively. Pathological examination revealed that cochlear synaptopathy was the most frequent cochlear pathology after blast exposure, which involved synapse loss in the inner hair cells without hair cell loss, depending on the power spectrum of the blast. This pathological change completely reflected the physiological analysis of wave I amplitude using auditory brainstem responses. Stereociliary bundle disruption in the outer hair cells was also dependent on the blast’s power spectrum. Therefore, we demonstrated that the dominant frequency of the blast power spectrum was the principal factor determining the region of cochlear damage. We believe that the presenting models would be valuable both in blast research and the investigation of various types of hearing loss whose pathogenesis involves cochlear synaptopathy.
To reveal the patency of the anterior epitympanic space (AES) and the surgical outcomes after transcanal endoscopic ear surgery (TEES) for attic cholesteatoma with a classification of anatomical ...variation of the AES.
Retrospective case review.
Tertiary referral center.
Seventy-four ears (72 patients with early-stage (I or II) attic cholesteatoma) aged between 16 and 85 years (mean: 48.9 yr) who underwent TEES between 2015 and 2017 were analyzed.
Tympanoplasty with atticoantrotomy was performed with TEES. TEES was performed using a rigid endoscope with an outer diameter of 2.7 mm.
The tensor fold in the AES anatomical classification, the postoperative patency of the AES evaluated by computer tomography images, and hearing outcomes based on the American Academy of Otolaryngology and Head and Neck Surgery criteria were evaluated after TEES for early-stage attic cholesteatoma.
There were 14 (18.9%) ears with a vertical tensor fold orientation, 29 (39.2%) ears with an oblique orientation, and 29 (39.2%) ears with a horizontal orientation. The total postoperative patency rate in the AES was 81.0%, without any significant difference in the anatomical variation in the AES, whereas the rate of preoperative complete tensor fold was 90.5%. Cholesteatoma recurrence was observed in three cases (4.1%), and all recurrent cases had obstructed AES. No significant difference was found in the postoperative air-bone gap regardless of the patency of the AES.
Our findings indicate that TEES is useful in restoring ventilation in the AES, resulting in favorable management of cholesteatoma.
Noise-induced hearing loss (NIHL) is one of the most common sensorineural hearing deficits. Recent studies have demonstrated that the pathogenesis of NIHL is closely related to ischemia-reperfusion ...injury of cochlea, which is caused by blood flow decrease and free radical production due to excessive noise. This suggests that protecting the cochlea from oxidative stress is an effective therapeutic approach for NIHL. NRF2 is a transcriptional activator playing an essential role in the defense mechanism against oxidative stress. To clarify the contribution of NRF2 to cochlear protection, we examined Nrf2(-/-) mice for susceptibility to NIHL. Threshold shifts of the auditory brainstem response at 7 days post-exposure were significantly larger in Nrf2(-/-) mice than wild-type mice. Treatment with CDDO-Im, a potent NRF2-activating drug, before but not after the noise exposure preserved the integrity of hair cells and improved post-exposure hearing levels in wild-type mice, but not in Nrf2(-/-) mice. Therefore, NRF2 activation is effective for NIHL prevention. Consistently, a human NRF2 SNP was significantly associated with impaired sensorineural hearing levels in a cohort subjected to occupational noise exposure. Thus, high NRF2 activity is advantageous for cochlear protection from noise-induced injury, and NRF2 is a promising target for NIHL prevention.
The development of more sensitive biomarkers for the detection of early-stage head and neck squamous cell carcinoma is needed.
This study was performed to assess the value of serum p53 antibody ...(s-p53-Ab) as a biomarker for oral and pharyngeal carcinoma.
Pre-treatment serum was collected for 71 patients with oral and pharyngeal carcinoma and 117 healthy volunteers as controls and analyzed s-p53-Ab using enzyme-linked immunosorbent assay (ELISA).
Using 1.3 U/mL as the cut-off value, 14 of 71 patients (sensitivity 19.7%), and 12 of 117 control cases were positive for s-p53-Ab (specificity 89.7%). Excluding 12 cases of p16-positive oropharyngeal and nasopharyngeal cancer which were all negative for s-p53-Ab, the sensitivity in early-stage 1-2 cases was 30.0%, which was higher than conventional tumor markers.
The s-p53-Ab was not detected in any cases of virus-related cancer in which p53 gene mutations were not involved in carcinogenesis. Since the s-p53-Ab sensitivity was high even in early-stage disease, s-p53-Ab measurement may be useful as an early diagnostic biomarker in patients with oral, p16- oropharyngeal, and hypopharyngeal cancer.
Abstract Transoral surgery is a less invasive treatment that is becoming a major strategy in the treatment of laryngo-pharyngeal cancer. It is a minimally invasive approach that has no skin incision ...and limits the extent of tissue dissection, disruption of speech and swallowing muscles, blood loss, damage to major neurovascular structures, and injury to normal tissue. Transoral approaches to the laryngo-pharynx, except for early glottis cancer, had been limited traditionally to tumors that can be observed directly and manipulated with standard instrumentation and lighting. Since the 1990s, transoral laser microsurgery (TLM) has been used as an organ preservation strategy with good oncological control and good functional results, although it has not been widely used because of its technical difficulty. Recently, transoral robotic surgery (TORS) is becoming popular as a new treatment modality for laryngo-pharyngeal cancer, and surgical robots are used widely in the world since United States FDA approval in 2009. In spite of the global spread of TORS, it has not been approved by the Japan FDA, which has led to the development of other low-cost transoral surgical techniques in Japan. Transoral videolaryngoscopic surgery (TOVS) was developed as a new transoral surgery system for laryngo-pharyngeal lesions to address the problems of TLM. In TOVS, a rigid endoscope is used to visualize the surgical field instead of a microscope and the advantages of TOVS include the wide operative field and working space achieved using the distending laryngoscope and videolaryngoscope. Also, with the spread of narrow band imaging (NBI), endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), which are widely used for superficial cancers in the gastrointestinal tract, have been applied for the superficial laryngo-pharyngeal cancer. Both EMR and ESD are performed mainly by gastroenterologists with a sharp dissector and magnifying endoscopy (ME)-NBI with minimal surgical margin. Endoscopic laryngo-pharyngeal surgery (ELPS) was developed to treat laryngo-pharyngeal superficial cancer by modifying the ESD procedure. The concept of ELPS is the same as that of ESD, however, the resection procedure is performed by a head and neck surgeon with both hands using a ME-NBI and rigid curved laryngo-pharyngoscope. These four procedures are low cost with similar oncological and functional outcomes to TORS. TORS may be less expensive than chemoradiotherapy, but the number of hospitals that can afford da Vinci surgical systems is limited. Even in the era of robotic surgery, these four procedures will be good options for laryngo-pharyngeal cancer.
Objective
To reveal the factors affecting the incidence of chorda tympani nerve (CTN) transection during middle ear surgery.
Study Design
Retrospective case review.
Setting
Tertiary referral center.
...Patients
We analyzed 232 ears (117 ears with cholesteatoma, 101 ears with chronic otitis media, and 14 ears with otosclerosis) that underwent tympanoplasty or stapes surgery during 2017–2020.
Intervention
Eighty‐four ears underwent transcanal endoscopic ear surgery (TEES), 103 ears underwent microscopic ear surgery (MES), and 45 ears underwent surgery using both endoscopy and microscopy (Dual).
Main Outcome Measure
To confirm CTN transection, intraoperative endoscopic/microscopic video images were evaluated. We used the same video images to determine the anatomical variation of the CTN course in the middle ear.
Results
In 18 ears (7.8%: 6/84 TEES ears 7.1%, 6/103 MES ears 5.8%, and 6/45 Dual ears 13.3%), the CTN was cut during middle ear surgery. There was no significant difference in CTN transection among groups. In cholesteatoma patients, stapes involvement resulted in a significantly higher CTN transection incidence. CTN anatomical variants such as the “Attached Short type” and “Ultrashort type” showed a significantly higher CTN transection incidence.
Conclusion
Although endoscopic surgery did not reduce the incidence of CTN transection during middle ear surgery, pathological involvement of the stapes and CTN anatomical variants, such as the “Attached Short type” and “Ultrashort type,” may increase this incidence. Preoperative evaluation of stapes involvement and anatomical location of the CTN course could help identify patients at greater risk for iatrogenic CTN transection.
Level of Evidence
4.
Although endoscopic surgery did not reduce the incidence of CTN cutting during middle ear surgery, pathological involvement of the stapes and a superior CTN course may increase this incidence. Preoperative evaluation of stapes involvement and anatomical location of the CTN course could help to prevent iatrogenic CTN injuries.
In this retrospective cohort study, we evaluated the oncological and functional outcomes of transoral videolaryngoscopic surgery (TOVS). Using distending laryngoscope and videolaryngoscope, wide ...operative field and working space could be obtained and tumor could be resected in en bloc. Sixty patients with T1, T2, and selected T3 laryngeal or pharyngeal squamous cell carcinomas (Stage I:
n
= 17, Stage II:
n
= 16, Stage III:
n
= 7, Stage IV:
n
= 20 cases) were enrolled and followed up for at least 24 months or until the patient’s death. Fifty-three patients underwent initial treatment, and seven patients had recurrent cancer after chemoradiation. In principle, node-positive patients underwent a simultaneous neck dissection. Patients with multiple nodal metastases or a positive surgical margin received postoperative radiotherapy. For initial treatment, the 5-year overall survival and disease-specific survival rates were 77 and 95 %, respectively. For supraglottic and hypopharyngeal cancers, the 5-year laryngeal preservation rates were 89 and 96 %, respectively. For salvage surgery, the overall survival, disease-specific survival, and laryngeal preservation rates were 75, 75, and 80 %, respectively. The median times before patients could resume eating and swallowing a soft diet were 6 and 9 days, respectively. The patients’ Functional Outcome Swallowing Scale stages were 0–2 in 93.3 % of the cases and 3 or 4 in 6.7 % of the cases. A percutaneous endoscopic gastrostomy was indicated for 1 (1.7 %) patient. Four (6.7 %) patients received transient tracheostomy. TOVS is a satisfactory and minimally invasive treatment option for laryngeal and pharyngeal cancers.
Background
Sentinel node navigation surgery using indocyanine green (ICG‐SNNS) can be performed in the operation room. The combination of minimally invasive transoral surgery (TOS) with ICG‐SNNS can ...provide functional preservation options for both primary lesions and lymph node (LN) metastasis. This multicenter feasibility study of this strategy was conducted in Japan.
Methods
Patients with clinical T1 or T2, N0 oropharyngeal, hypopharyngeal, or supraglottic cancer were enrolled. The identification rate of sentinel nodes, delayed cervical LN metastasis in 2 years, and survival rate were assessed.
Results
Twenty‐two patients (10 oropharynx, 8 hypopharynx, 4 supraglottic cancer) were enrolled. The identification rate was 100%. One case had delayed nodal metastasis. The accuracy was 95.5%, sensitivity was 75%, and specificity was 100%. The 5‐year disease‐specific survival was 100%, overall survival was 72.3%, and disease‐free survival was 60.5%.
Conclusions
The combination of TOS with ICG‐SNNS is feasible as a minimally invasive strategy and has favorable oncological outcomes.
Tracheal stenosis is a refractory and recurrent disease induced by excessive cell proliferation within the restricted tracheal space. We investigated the role of extracellular signal-regulated kinase ...(ERK), which mediates a broad range of intracellular signal transduction processes in tracheal stenosis and the therapeutic effect of the MEK inhibitor which is the upstream kinase of ERK. We histologically analyzed cauterized tracheas to evaluate stenosis using a tracheal stenosis mouse model. Using Western blot, we analyzed the phosphorylation rate of ERK1/2 after cauterization with or without MEK inhibitor. MEK inhibitor was intraperitoneally injected 30 min prior to cauterization (single treatment) or 30 min prior to and 24, 48, 72, and 96 hours after cauterization (daily treatment). We compared the stenosis of non-inhibitor treatment, single treatment, and daily treatment group. We successfully established a novel mouse model of tracheal stenosis. The cauterized trachea increased the rate of stenosis compared with the normal control trachea. The phosphorylation rate of ERK1 and ERK2 was significantly increased at 5 min after the cauterization compared with the normal controls. After 5 min, the rates decreased over time. The daily treatment group had suppressed stenosis compared with the non-inhibitor treatment group. p-ERK1/2 activation after cauterization could play an important role in the tracheal wound healing process. Consecutive inhibition of ERK phosphorylation is a potentially useful therapeutic strategy for tracheal stenosis.
Prophylactic elective neck dissection (ND) with navigation surgery using radioisotope-based sentinel lymph node biopsy (SLNB) is non-inferior to elective ND in terms of survival but has an advantage ...in postoperative functional disability. We conducted a subgroup analysis to identify predictive factors for false-negative (FN)-SLNB in patients with early oral cavity cancer. This study is a supplementary analysis using the dataset of a previously reported randomized clinical trial on SLN navigation surgery for oral cancers. This study investigated the association of clinical and SLN-related factors with false-negative cases in the SLNB group. From 2011 to 2016, 275 patients were enrolled and randomly assigned to the ND and SLNB study groups, with 134 patients assigned to the SLNB group. In the SLNB group, seven cases with negative SLNs and neck recurrences were judged as FN-SLNBs according to the general definition. The number of detected SLNs with and without adjusting for the propensity score was significantly associated with FNs in the logistic analysis. FN-SLNB was associated with the number of identified SLNs, suggesting the need for careful postoperative monitoring for neck recurrence in patients with one or two identified SLNs after acquiring sufficient experience in the identification technique.