Efficacy of Surgical Reconstruction With Rectus Abdominis Flap Following en Bloc Resection of the Orbital Contents for Malignant Lacrimal Gland Cancer: A Case Series.

In cases of lacrimal gland carcinoma requiring surgical excision of the orbital contents, skull base, and surrounding bones, definitive blockage of the cranial cavity and reconstruction of the anterior skull base with irradiation-acceptable tissue (for possible subsequent radiotherapy) is necessary. However, considerations for quality of life, including cosmetic aspects, such as artificial eye placement and contour morphology, make reconstruction challenging. In three cases of advanced lacrimal gland carcinoma, we performed a reconstruction surgery following an en bloc resection of the orbital contents and lateral orbital bones. A rectus abdominis flap was used, considering both function and morphology. This flap, characterized by reliable anatomical structure and good blood flow, adequately filled the three-dimensional dead space. In our case, the flap fully survived, and no complications such as cerebrospinal fluid leakage or meningitis were observed. Six months after surgery, the flap volume was 31.7-73.3% of its initial size. Considering potential flap shrinkage in the future, it was deemed beneficial to use a slightly excessive volume.

Different characteristics of the tumor immune microenvironment among subtypes of salivary gland cancer.

AIM: Although immune checkpoint inhibitors (ICPi) for salivary gland cancer (SGC) have been investigated in clinical trials, details of the tumor immune microenvironment (TIME) remain unclear. This research aimed to elucidate the TIME of SGC and its relationship with tumor mutation burden (TMB) and to explore the rationale for the applicability of ICPi. MATERIALS AND METHODS: We selected five pathological types, namely adenoid cystic carcinoma (ACC); adenocarcinoma, not otherwise specified (ANOS); salivary duct carcinoma (SDC); and low/high-grade mucoepidermoid carcinoma (MEClow/high). We investigated the TIME and TMB of each pathological type. TIME was evaluated by multiplexed fluorescent immunohistochemistry. TMB was measured by next-generation sequencing. RESULTS: ACC and MEChigh showed the lowest and highest infiltration of immune effector and suppressor cells in both tumor and stroma. ANOS, SDC, and MEClow showed modest infiltration of immune effector cells in tumors. Correlation analysis showed a positive correlation between CD3+CD8+ T cells in tumor and TMB (r = 0.647). CD3+CD8+ T cells in tumors showed a positive correlation with programmed cell death-ligand 1 expression in tumor cells (r = 0.513) and a weak positive correlation with CD3+CD4+Foxp3+ cells in tumors (r = 0.399). However, no correlation was observed between CD3+CD8+ T cells and CD204+ cells in tumors (r = -0.049). CONCLUSION: The TIME of ACC was the so-called immune desert type, which may explain the mechanisms of the poor response to ICPi in previous clinical trials. On the other hand, MEChigh was the immune-inflamed type, and this may support the rationale of ICPi for this pathological subtype.

Clinical, genomic and immune microenvironmental determinants of nivolumab response in head and neck squamous cell carcinoma.

Background: In view of improving biomarkers predicting the efficacy of immunotherapy for head and neck squamous cell carcinoma (R/M HNSCC), this multicenter retrospective study aimed to identify clinical, tumor microenvironmental, and genomic factors that are related to therapeutic response to the anti- Programmed cell death protein 1 (PD-1) antibody, nivolumab, in patients with R/M HNSCC. Methods: The study compared 53 responders and 47 non-responders, analyzing formalin-fixed paraffin-embedded samples using 14-marker multiplex immunohistochemistry and targeted gene sequencing. Results: Of 100 patients included, responders had significantly lower smoking and alcohol index, higher incidence of immune related adverse events, and higher PD-1 ligand (PD-L1) expression in immune cells as well as PD-L1 combined positive score (CPS) than non-responders. The frequency of natural killer cells was associated with nivolumab response in patients with prior cetuximab use, but not in cetuximab-naïve status. Age-stratified analysis showed nivolumab response was linked to high CPS and lymphoid-inflamed profiles in patients aged ≥ 65. In contrast, lower NLR in peripheral blood counts was associated with response in patients aged < 65. Notably, TP53 mutation-positive group had lower CPS and T cell densities, suggesting an immune-excluded microenvironment. Patients with altered tumor suppressor gene pathways, including TP53, CDKN2A, and SMAD4 mutations, had lower CPS, higher smoking index, and were associated with poor responses. Conclusion: Nivolumab treatment efficacy in HNSCC is influenced by a combination of clinical factors, age, prior treatment, immune environmental characteristics, and gene mutation profiles.

Survival Outcome Superiority of Total Pharyngolaryngectomy Compared with Chemoradiotherapy for T4aM0 Hypopharyngeal Squamous Cell Carcinoma: A Nationwide Database Study of Japan.

BACKGROUND: The purpose of this study is to elucidate whether total pharyngolaryngectomy (TPL) or chemoradiotherapy (CRT) provides a better prognostic outcome in patients with T4aM0 hypopharyngeal carcinoma (HPSCC) using a nationwide database. METHODS: All data were obtained from the Head and Neck Cancer Registry of Japan, and information from patients who were newly diagnosed with T4aM0 HPSCC between 2011 and 2015 was extracted. The primary endpoint was disease-specific survival (DSS), and the secondary endpoint was overall survival (OS). The inverse probability of treatment weighting (IPTW) adjustments was used for survival analyses. RESULTS: Our cohort included 1143 patients. The TPL and CRT groups included 724 and 419 patients, respectively. Following IPTW adjustments, both the OS and DSS of the TPL group were significantly longer than those of the CRT group (P = .02 and P = .002, respectively). CONCLUSIONS: Survival superiority was demonstrated for patients with T4aM0 HPSCC treated with TPL compared with those treated with CRT.

Clinical benefits of combining oral cytotoxic chemotherapeutic agents with radiotherapy in patients with T2N0 glottic squamous cell carcinoma based on the reports of the Head and Neck Cancer Registry of Japan.

BACKGROUND: T2N0 glottic squamous cell carcinoma (SCC) typically responds well to radiotherapy (RT); however, achieving local control remains challenging. In cases of RT failure, total laryngectomy may be necessary. Improved local control and preservation of the larynx directly enhances patients' quality of life. Our retrospective analysis using the Japan Head and Neck Cancer Registry (JHNCR) aimed to compare the clinical benefits of RT and chemoradiotherapy (CRT) in patients with T2N0 glottic SCC. METHODS: Using data from the JHNCR (2011-2015), we included 1,231 patients with T2N0 glottic SCC. Among them, 346 received curative RT and 425 underwent curative CRT. The CRT group was further divided into the oral CRT (Oral CRT, N=120) and intravenous CRT (DIV CRT, N=305) groups. This study assessed local control rate (LCR), progression-free survival (PFS), and overall survival (OS). A 1:1 propensity score-matching analysis was used to adjust for patient characteristics. RESULTS: After matching, 105 pairs compared RT with Oral CRT, and 224 pairs compared RT with DIV CRT. The variables were well-balanced in the matched populations. In the matched populations, the Oral CRT group had significantly better 5-year LCR and PFS than the RT group (LCR, 89.4 % vs. 80.6 %, P=0.043; and PFS, 85.5 % vs. 72.3 %, P=0.025, respectively), while the DIV RT group had significantly better 5-year PFS than the RT group (80.1 % vs. 68.6 %, P=0.026). CONCLUSIONS: The clinical benefits of better local and disease controls were observed when oral chemotherapy was added to RT in patients with T2N0 glottic SCC. Thus, the significance of adding oral chemotherapeutic agents to RT in the treatment of T2N0 glottic SCC requires further prospective investigation.

Differential expression of epidermal growth factor receptor in various pathological types of salivary gland cancers.

OBJECTIVE: While several studies reported epidermal growth factor receptor (EGFR) expression in salivary gland cancer (SGC), results varied due to a lack of unified definition of EGFR positivity. In this study, we assessed the EGFR expression level using both EGFR positive score and cumulative EGFR score in the patients with SGC. METHODS: Between January 2010 and April 2021, 102 patients with SGC who underwent surgical resection were reviewed retrospectively by immunohistochemistry. The membrane staining intensity was scored as follows: no staining (0), weak staining (1+), intermediate staining (2+), and strong staining (3+). The cumulative EGFR score was determined on a continuous scale of 0-300 using the formula:1 × (1+: percentage of weakly stained cells) + 2 × (2+: percentage of moderately stained cells) + 3 × (3+: percentage of strongly stained cells). RESULTS: EGFR expression in SGC varied widely even among the same as well as different histopathological types. The average EGFR positive scores were 46.0 %, 55.7 %, 51.6 %, 1.0 %, 26.8 %, 50 %, and 76.8 % for mucoepidermoid carcinoma (MEC), salivary duct carcinoma (SDC), adenoid cystic carcinoma (AdCC), acinic cell carcinoma (AcCC), adenocarcinoma NOS (ACNOS), carcinoma ex pleomorphic adenoma (CAexPA), and squamous cell carcinoma (SqCC), respectively. The average cumulative EGFR scores were 82, 91, 80, 1, 52, 93, and 185 for MEC, SDC, AdCC, AcCC, ACNOS, CAexPA, and SqCC, respectively. CONCLUSIONS: EGFR positive scores and cumulative EGFR scores in SGCs varied among the various histological types, and even in the same histological type. These scores may predict the clinical outcome of SGC treated with EGFR-targeting therapies, such as head and neck photoimmunotherapy, and need to be evaluated in future studies.

A Case of Olfactory Neuroblastoma Developing Bilateral Retropharyngeal Lymph Node Metastasis 14-years After Skull Base Surgery.

Olfactory neuroblastoma (ONB) is an uncommon malignant tumor and is usually treated by a multidisciplinary approach includes surgery, radiotherapy, and chemotherapy. A 62 years-old male had a tumor in the nasal cavity and diagnosed as ONB with Kadish A stage. Anterior skull base surgery was performed as radical treatment. Since the surgical margin was negative, no postoperative radiotherapy was administered. 14 years after the surgery, bilateral otitis media with effusion (OME) was occurred, we found the recurrence tumor at bilateral retropharyngeal lymph node (RPLN) which surrounded the internal carotid arteries. Since these were unresectable, we planned chemoradiotherapy which was 70Gy of intensity modulated radiotherapy combined with two courses of carboplatin and etoposide. The tumor volume was reduced and bilateral OME were improved. He has been alive for 3 years after salvage treatment. Although ONB has a relatively good prognosis, it is known to often cause cervical lymph node metastasis. Grades III and IV of Hyams classification are considered high risk. This case, initial tumor was limited in the nasal cavity and its clinical classification was early stage, but Hyams classification was grade III. In reference to this case, considering that RPLN metastasis are difficult to radically resect at the salvage surgery, including this area in postoperative radiotherapy was considered an option.

Oncological Outcomes of Concurrent Chemoradiotherapy and Surgical Treatment for Patients With T3 Hypopharyngeal Cancer: A Single-Center Retrospective Analysis.

Background Since the larynx and pharynx are vital for respiration, swallowing, and speech, chemoradiotherapy (CRT) has been widely applied for T3 hypopharyngeal cancer (HPC) as an organ-preserving treatment. However, CRT can lead to severe late adverse events such as dysphagia and aspiration pneumonia, especially in patients who have difficulty swallowing and/or aspiration at the time of initial diagnosis. Patients and methods Between 2012 and 2020, 86 patients with T3 HPC treated with curative intent at Kobe University Hospital were included in this study. The average age was 69 years old, ranging from 43 to 89. Diseases were classified as Stage III in 29 patients, Stage IVA in 52 patients, and Stage IVB in five patients. Thirty-five (41%) patients were treated by CRT, and 51 (59%) patients were treated by surgery. Patients were followed up for at least two years, and the follow-up period ranged from four to 128 months (median: 45 months). Results Three-year progression-free survival (PFS) rates of patients treated by CRT and patients treated by surgery were 56.2% and 60.3%, respectively. Three-year disease-specific survival (DSS) rates of patients treated by CRT and surgically treated patients were 79.0% vs. 70.8%, respectively. Three-year overall survival (OS) rates of patients treated by CRT and surgically treated patients were 64.5% and 69.0%, respectively. Of note, a significant difference was observed between three-year DSS and three-year PFS (79.0% vs. 56.2%, p = 0.0014) in the patients treated by CRT but not in the patients treated by surgery. Conclusions No significant differences were observed between the PFS, DSS, and OS rates of patients treated by CRT and those of surgically treated patients. Locoregional recurrences after CRT were significantly successfully salvaged by surgical intervention. These results suggest that CRT can be applied as an alternative to surgery without reducing survival, especially for patients without severe clinical symptoms. Meticulous follow-up is mandatory for early detection of recurrence to salvage by surgery and for the management of late adverse events.

Human papillomavirus-driven head and neck cancers in Japan during 2008-2009 and 2018-2019: The BROADEN study.

There is limited understanding of epidemiology and time trends of human papilloma virus (HPV)-driven head and neck cancers (HNC) in Japan, especially outside of the oropharynx. To assess HPV-driven HNC, a non-interventional study (BROADEN) of HNC patients diagnosed in 2008-2009 and 2018-2019 was conducted in Japan. Adult patients with oropharyngeal, nasopharyngeal, laryngeal, hypopharyngeal or oral cavity cancers were included in this study. HPV was centrally tested using p16INK4a immunohistochemistry, HPV-DNA PCR and HPV E6*I mRNA. HPV attributability required positivity in at least two tests (p16INK4a immunohistochemistry, HPV-DNA PCR, HPV E6*I mRNA) in the oropharynx, and HPV-DNA and HPV E6*I mRNA positivity for non-oropharynx sites. Nineteen hospitals included a total of 1108 patients, of whom 981 had valid samples. Men accounted for 82% of HNC diagnoses. Patients in the earlier cohort were younger and included a higher percentage of smokers. There was an increasing trend of HPV-driven oropharyngeal cancer over the last decade, from 44.2% to 51.7%. HPV attribution in nasopharyngeal cancers was 3.2% in 2008-2009 and 7.5% in 2018-2019; and 4.4% and 0% for larynx respectively. In total, 95.2% of HPV-driven HNC were attributed to HPV genotypes included in the 9-valent HPV vaccine being HPV16 the most prominent genotype. These results suggest that an epidemiologic shift is happening in Japan, with a decrease in smoking and alcohol use and an increase in HPV-driven HNC. The increasing trend of HPV-driven HNC in Japan highlights the need for preventive strategies to mitigate the rise of HPV-driven HNC.

Skull base surgery for malignant tumors: The 2nd international collaborative study (1995-2015).

BACKGROUND: The current study presents the effort of a global collaborative group to review the management and outcomes of malignant tumors of the skull base worldwide. PATIENTS AND METHODS: A total of 28 institutions contributed data on 3061 patients. Analysis evaluated clinical variables, survival outcomes, and multivariable factors associated with outcomes. RESULTS: The median age was 56 years (IQR 44-67). The open surgical approach was used in 55% (n = 1680) of cases, endoscopic resection was performed in 36% (n = 1087), and the combined approach in 9.6% (n = 294). With a median follow-up of 7.1 years, the 5-year OS DSS and RFS were 65%, 71.7% and 53%, respectively. On multivariable analysis, older age, comorbidities, histology, dural/intracranial involvement, positive margins, advanced stage, and primary site were independent prognostic factors for OS, DSS, and RFS. Adjuvant RT was a protective prognostic factor. CONCLUSION: The progress across various disciplines may have contributed to improved OS and DSS in this study compared to previous reports.

Indocyanine green fluorescence visualizes landmark arteries for endoscopic sinus and skull base surgery.

OBJECTIVE: Landmark arteries during endoscopic sinus surgery are currently identified on the basis of anatomy, CT imaging and navigation, and Doppler flowmetry. However, the advantage of intraoperative fluorescence imaging during endoscopic sinus surgery has not been demonstrated. This study aimed to investigate whether Indocyanine Green (ICG) is useful for visualizing landmark arteries during endoscopic sinus and skull base surgery. METHODS: Eight patients who underwent endoscopic sinus and pituitary surgeries and consented to study participation were included. After planned procedures were performed as usual, landmark arteries were examined by ICG endoscope. Recorded video and preoperative CT images were analyzed for identification of five landmark arteries: anterior ethmoidal artery (AEA), posterior ethmoidal artery (PEA), internal carotid artery (ICA), sphenopalatine artery (SPA), and postnasal artery (PNA). Identification of arteries was evaluated three grades: identifiable, locatable, unrecognizable. RESULTS: Eight patients and eleven sides were evaluated. The ICG dose was 2.5 mg/body and a single shot was sufficient for evaluation. 100 % of AEA was identified (9/9 sides), 86 % of PNA (6/7 sides), 56 % of ICA (5/9 sides), and 25 % of PEA and SPA (2/8 sides). CONCLUSION: ICG could visualize landmark arteries, even thin arteries like AEA, during endoscopic sinus and skull base surgeries. Visualization was affected by thickness of bone or soft tissue above arteries, blood clots, sensitivity setting, and angle and distance of near-infrared light irradiation. ICG visualization of landmark arteries may help avoid vascular injuries during endoscopic sinus and skull base surgeries, particularly of AEA, PNA and ICA.

Targeting Anterior Commissure Involvement with Hyperfractionated Radiotherapy for T1-T2 Squamous Cell Carcinoma of the Glottic Larynx.

Anterior commissure is involved in about 20% of early-stage glottic squamous cell carcinomas (EGSCCs). Treatment outcomes and prognostic factors for EGSCC with anterior commissure involvement (ACI) were evaluated by focusing on hyperfractionated radiotherapy (74.4 Gy in 62 fractions). One-hundred and fifty-three patients with T1-T2 EGSCC were included in this study. The median total doses for T1a, T1b, and T2 were 66, 74.4, and 74.4 Gy, respectively. Overall, 49 (32%) patients had T1a, 38 (25%) had T1b, and 66 (43%) had T2 disease. The median treatment duration was 46 days. The median follow-up duration was 5.1 years. The 10-year overall and cause-specific survival rates were 72% and 97%, respectively. The 10-year local control rates were 94% for T1a, 88% for T1b, and 81% for T2 disease. Local control rates in patients with ACI were slightly better than those in patients without ACI with T1a and T1b diseases; however, the difference was not significant. The 10-year laryngeal preservation rate was 96%. Six patients experienced grade 3 mucositis, and four patients had grade 3 dermatitis. Hyperfractionated radiotherapy was effective for T1 disease with ACI, but insufficient for T2 disease with ACI. Our treatment strategy resulted in excellent laryngeal preservation.

Induction of Immunological Antitumor Effects by the Combination of Adenovirus-Mediated Gene Transfer of B7-1 and Anti-Programmed Cell Death-1 Antibody in a Murine Squamous Cell Carcinoma Model.

BACKGROUND: The goal of this study was to evaluate the antitumor immune effects of B7-1 gene expression in addition to immune checkpoint inhibitor against squamous cell carcinoma. METHODS: A murine SCC cell line, KLN205, was infected with adenoviral vector carrying B7-1 (AdB7). Infected cells were injected subcutaneously in the flanks of DBA/2 mice. Three weeks after implantation, anti-mouse PD-1 antibody (antiPD1) was intraperitonially administrated twice a week for a total of six times. RESULTS: CD80 was significantly overexpressed in the AdB7-infected tumors. IFN-gamma in the T cells in the spleen was significantly increased and tumor size was significantly reduced in the mice treated with both AdB7 and antiPD1. Targeted tumors treated with both AdB7 and antiPD1 exhibited significantly increased cell densities of total immune cells as well as Ki-67+ CD8+ T cells and decreased regulatory T cells. CONCLUSIONS: These results suggest that the B7-1 gene transfer may enhance the antitumor effect of anti-PD1 antibody against SCC.

Expression of EGFR and p16 in Squamous Cell Carcinoma of External Auditory Canal.

The expression of EGFR and p16 in the external auditory canal squamous cell carcinoma (EACSCC) and their impacts on oncological outcomes were not well studied. Seventeen-one consecutive patients who were treated for EACSCC at Kobe University Hospital from 1995 to 2018 were enrolled in this study. The expression of EGFR, and p16 were evaluated and their impacts on oncological outcomes were statistically analyzed. Positive expression of EGFR was observed in 62 patients (87%). Strong positive expression of p16 were observed in 18 patients (32.4%), and weakly positive expression in 30 patients (42.3%), respectively. While the number of the patients with negative EGFR expression were limited, all the surgically treated patients with negative EGFR expression have been alive without disease. In the patients with T3 & T4a EACSCC, prognosis of the patients with positive p16 expression EACSCC tended to be better than those with negative p16 expression. These results suggest the clinical significance of EGFR and p16 expressions in the patients with advanced EACSCC to predict oncological outcomes.

Summary of Japanese clinical practice guidelines for head and neck cancer - 2022 update edited by the Japan society for head and neck cancer.

The aim of the "Japanese Clinical Practice Guidelines for Head and Neck Cancer - 2022 Update" is to review the latest evidence regarding head and neck cancer and to present the current standard approaches for diagnosis and treatment. These evidence-based recommendations were created with the consensus of the Guideline Committee, which is composed of otorhinolaryngologists and head and neck surgeons, together with radiologists, radiation oncologists, medical oncologists, plastic surgeons, dentists, palliative care physicians, and rehabilitation physicians. These guidelines were created by the Clinical Practice Guideline Committee of the Japan Society for Head and Neck Cancer based on the "Head and Neck Cancer Treatment Guidelines 2018 Edition," and the revised draft was compiled after evaluation by the Assessment Committee and public comments. The 'Clinical questions and recommendations' section consists of 13 categories, and 59 clinical questions are described in total. Here we describe 6 clinical questions specific to other sets of guidelines with recommendations and comments.

Definitive radiotherapy for nasopharyngeal carcinoma in Japan: analysis of cases in the National Head and Neck Cancer Registry from 2011 to 2014.

OBJECTIVE: This study aimed to analyze the nationwide prognosis of patients with nasopharyngeal carcinoma who underwent definitive radiotherapy in Japan, utilizing the National Head and Neck Cancer Registry data. METHODS: A total of 741 patients diagnosed with primary nasopharyngeal carcinoma were screened from 2011 to 2014. The inclusion criteria were histologically proven nasopharyngeal squamous cell carcinoma, receiving definitive radiotherapy, and no distant metastases. Patients with unclear prognoses or unknown staging were excluded. The primary endpoint was 5-year overall survival, and secondary endpoints were 5-year progression-free survival and survival by stage. RESULTS: A total of 457 patients met the inclusion criteria. The median age was 60 years, and 80% were male. The proportions of patients with performance status 0, 1, 2 and 3 were 69, 10, 1 and 1%, respectively. Chemoradiotherapy was administered to 84.7%. Radiotherapy modalities were recorded only for 29 patients (three received intensity-modulated radiotherapy and 26 received two/three-dimensional radiotherapy). Of those included, 7.4, 24.7, 35.7, 24.5 and 7.7% had Stage I, II, III, IVA and IVB disease, respectively. The 5-year overall survival was 72.5% for all patients: 82.6, 86.6, 76.0, 51.4 and 66.5% for Stage I, II, III, IVA and IVB disease, respectively. The 5-year progression-free survival was 58.6%: 75.6, 66.8, 61.5, 43.7 and 46.5% for Stage I, II, III, IVA and IVB disease, respectively. CONCLUSIONS: This nationwide survey demonstrated favorable prognoses and provided valuable foundational data for similar future surveys to monitor the penetration of appropriate treatment and changes in clinical structures based on new evidence.

Radiotherapy with or without chemotherapy for locally advanced head and neck cancer in elderly patients: analysis of the Head and Neck Cancer Registry of Japan.

BACKGROUND: Whether concurrent chemotherapy with radiotherapy (CRT) is effective for elderly patients with head and neck cancer is a controversial topic. This study aimed to analyze the effectiveness of CRT vs. radiation therapy (RT) among elderly patients in Japan. METHODS: Data from the Head and Neck Cancer Registry of Japan were extracted and analyzed. Patients with locally advanced squamous cell carcinoma of the oropharynx, hypopharynx, or larynx who received definitive CRT or RT between 2011 and 2014 were included. RESULTS: CRT was administered to 78% of the 1057 patients aged ≥ 70 years and 67% of the 555 patients aged ≥ 75 years. For the patients aged ≥ 75 years, the overall survival (OS) rate was significantly better in the CRT group than in the RT group (P < 0.05), while the progression-free survival (PFS) rate was not significantly different (P > 0.05). The add-on effect of CRT was significantly poor in elderly patients (P < 0.05), and it was not a significant factor in the multivariate analysis for patients aged ≥ 75 years. After propensity score matching, there were no significant differences in the OS and PFS rates between the patients aged ≥ 70 years and those aged ≥ 75 years (all, P > 0.05). CONCLUSION: Although aggressive CRT is administered to elderly patients in Japan, its effectiveness is uncertain. Further prospective randomized trials are needed to verify whether CRT is superior to RT alone for elderly patients.

Vestibular function after simultaneous bilateral cochlear implantation in adults.

Introduction: Binaural hearing enhances speech intelligibility, source localization, and speech comprehension in noisy environments. Although bilateral cochlear implantation (CI) offers several benefits, concerns arise regarding the risk of bilateral postoperative vestibular dysfunction with simultaneous CI. This study aimed to longitudinally evaluate changes in vestibular function in adult patients who underwent simultaneous bilateral CI using minimally invasive electrodes and surgical techniques. Methods: A retrospective review was conducted on 10 patients who underwent simultaneous bilateral CI at our hospital. Vertigo symptoms and vestibular function test results were examined preoperatively, 1-6 months postoperatively, and 1 year postoperatively. Nystagmus tests, caloric reflex tests, vestibular evoked myogenic potentials (VEMP) measurements, and static stabilometry were performed as vestibular function tests. Results: Although an initial transient decline in vestibular function was observed, no significant long-term decline was observed in the caloric reflex test, ocular VEMP (oVEMP), or cervical VEMP (cVEMP). Moreover, regardless of the presence or absence of abnormalities in caloric reflex, oVEMP, or cVEMP, no significant deterioration was detected in the static stabilometer test. While two patients reported preoperative dizziness, all patients were symptom-free 1 year postoperatively. Discussion: The findings suggest that using current minimally invasive electrodes and surgical techniques in simultaneous bilateral CI leads to temporary vestibular function decline postoperatively. However, most patients experience a recovery in function over time, highlighting the potential safety and efficacy of the procedure. Simultaneous bilateral CI surgery is viable, depending on the patient's auditory needs and burden.

Corrigendum: Influences of Orogastric and Nasogastric Tubes on Sucking Pressure during Bottle Feeding in Immature Infants.

This corrects the article in Kobe J Med Sci. 2023 May 31; 69(1): E25-E32.

Live Imaging of the Dehydration Effect of Isosorbide on the Normal and Hydropic Guinea Pig Cochleae Using Optical Coherence Tomography.

OBJECTIVE: To investigate the isosorbide-induced dehydration effect on the endolymphatic space by intratympanic administration of isosorbide. BACKGROUND: Isosorbide, an osmotic diuretic, is used orally as a typical conservative therapy for Menière's disease (MD) in Japan. The dehydration effect occurs 6 hours after isosorbide ingestion. Intratympanic administration of isosorbide resolves endolymphatic hydrops faster than oral ingestion. In addition, the dehydration effect has never been shown directly. Therefore, we investigated the dehydration effect of intratympanic administration of isosorbide on endolymphatic hydrops using optical coherence tomography. METHODS: We used eight Hartley guinea pigs, divided into normal and hydrops groups. In the hydrops group, the animals underwent endolymphatic sac obliteration to create endolymphatic hydrops. We obtained midmodiolar section images of the cochleae using optical coherence tomography. Then, 50 to 70% isosorbide was sequentially administered intratympanically for 5 minutes, and the apical turn of the cochlea was observed. The relative midmodiolar cross-sectional area of the scala media was calculated for quantitative assessment of the endolymphatic space. RESULTS: In the normal group, 50% isosorbide had a slight but significant dehydration effect on the scala media; at 55 to 70%, Reissner's membrane became flat. In the hydrops group, 50% isosorbide slightly reduced endolymphatic hydrops; 65% flattened Reissner's membrane, and 70% slightly concaved it toward the basilar membrane. CONCLUSION: The results suggest that we could select the concentration of isosorbide according to the stage or severity of MD and relief from acute attack. Intratympanic administration of isosorbide may be a promising treatment for patients with MD.