[Allergen-specific immunotherapy : A brief overview in association with allergic conjunctivitis]

Allergen-specific immunotherapy (AIT) is the only causal and disease-modifying treatment for immunoglobulin E (IgE)-mediated type I allergies. Regular exposure to the causative allergen results in an immunomodulatory effect by which the predominant T‑helper (Th) 2 lymphocyte response is shifted to a Th1 lymphocyte response and more allergen-specific blocking immunoglobulins are produced. The approval of substances for AIT is regulated by the Therapy Allergens Ordinance (TAV). There are subcutaneous and/or sublingual AITs for the following indications: allergic rhinitis, allergic conjunctivitis, allergic asthma and insect venom allergy. In this article the indications for allergic conjunctivitis are discussed in particular. Clinical symptoms and a relevant type 1 sensitization are the prerequisites for the indications for AIT. The assessment of the indications and carrying out an AIT should only be carried out by physicians who have been trained in allergology.

Significance of endolymphatic sac surgery with and/or without simultaneous cochlea implant surgery in respect of vertigo control and speech perception in patients with Menière's disease

PURPOSE

The focus on treating patients with Menière's Disease (MD) lies on the reduction of vertigo attacks and the preservation of sensory function. Endolympathic hydrops is considered as an epiphenomenon in MD, which can potentially be altered by endolymphatic sac surgery (ESS). Purpose of the study was to investigate the influences on vertigo control through manipulation of the perilymphatic system with or without ESS.

METHODS

Retrospective data analysis of 86 consecutive patients with MD according to current diagnostic criteria after endolymphatic sac surgery alone (ESSalone; n = 45), cochlear implantation (CI) alone (CIalone; n = 12), and ESS with CI (ESS + CI; n = 29), treated at a tertiary referral center.

MAIN OUTCOME MEASURES

vertigo control, speech perception pre- and postoperatively.

RESULTS

Gender, side, and preoperative treatment were similar in all groups. Age was younger in the ESSalone-group with 56.2 ± 13.0 years (CIalone = 64.2 ± 11.4 years; ESS + CI = 63.1 ± 9.7 years). Definitive MD was present in all the CIalone, in 79.3% of the ESS + CI and in 59.6% of the ESSalone-patients. Likewise, vertigo control rate was 100% in the CIalone, 89.7% in the ESS + CI and 66.0% in the ESSalone-group.

CONCLUSIONS

Vertigo control was improved in all three groups, however, superior in groups treated with CI, potentially contributed by the manipulation of both the endo- and perilymphatic systems. A more systematic characterization of the patients with larger case numbers and documentation of follow up data would be needed to evaluate a clinical effect more properly.

Direct-to-Consumer Teledermatology in Germany: A Retrospective Analysis of 1,999 Teleconsultations Suggests Positive Impact on Patient Care

Background: There is a high demand for dermatological care in Germany. As use of teledermatology has increased significantly, this study aimed to investigate the impact of teledermatology on patient care. Methods: This retrospective cross-sectional study used data from a direct-to-consumer teledermatology platform using store-and-forward technology available in Germany between July 2021 and April 2022. Additional patient characteristics were collected using a voluntary follow-up questionnaire, 28 days after teleconsultation. Results: Data of 1,999 enrolled patients were evaluated. Patients had a mean age of 36 years, and 61.2% (1,223/1,999) lived in a rural residence. The most common diagnoses included eczema (36.0%, 701/1,946), fungal diseases (15.4%, 299/1,946), and acne (12.5%, 243/1,946). The follow-up questionnaire was answered by 166 patients (8.3%, 166/1,999). In total, 42.8% (71/166) of patients had undergone no previous medical consultation. The most frequent reason for using teledermatology was the waiting time for a dermatology outpatient appointment (62.0%, 103/166). A total of 62.0% (103/166) participants rated the treatment success as good or very good, while 86.1% (143/166) rated the quality of telemedical care as equal or better to that of an outpatient visit. Conclusion: This study showed that patients often use teledermatology because of functional barriers (waiting times). In this cohort, the diagnoses strongly corresponded to reasons for outpatient presentation. Most patients rated the quality of teledermatology service as at least equivalent to that of outpatient physician visits and reported treatment success. Thus, teledermatology can relieve the burden of outpatient care while providing high benefits from the patient's perspective.

Randomized, placebo-controlled study on efficacy, safety and tolerability of drug-induced defibrinogenation for sudden sensorineural hearing loss: the lessons learned

PURPOSE

Disturbance of cochlear microcirculation is discussed as final common pathway of various inner ear diseases. Hyperfibrinogenemia causing increased plasma viscosity is a possible factor for a critical reduction of cochlear blood flow that might lead to sudden sensorineural hearing loss (SSHL). The aim was to determine the efficacy and safety of drug-induced defibrinogenation by ancrod for SSHL.

METHODS

Double-blind, randomized, placebo-controlled, multicenter, parallel group, phase II (proof-of-concept) study (planned enrollment: 99 patients). Patients received an infusion of ancrod or placebo (day 1) followed by subcutaneous administrations (day 2, 4, 6). Primary outcome was the change in pure tone audiogram air conduction average until day 8.

RESULTS

The study was terminated early due to slow recruiting (31 enrolled patients: 22 ancrod, 9 placebo). A significant improvement of hearing loss was registered in both groups (ancrod: - 14.3 dB ± 20.4 dB, - 39.9% ± 50.4%; placebo: - 22.3 dB ± 13.7 dB, - 59.1% ± 38.0%). A statistically significant group-difference was not detected (p = 0.374). Placebo response of 33.3% complete and 85.7% at least partial recovery was observed. Plasma fibrinogen levels were reduced significantly by ancrod (baseline: 325.2 mg/dL, day 2: 107.2 mg/dL). Ancrod was tolerated well, no adverse drug reaction was of severe intensity, no serious adverse events occurred.

CONCLUSION

Ancrod reduced fibrinogen levels that support its mechanism of action. The safety profile can be rated positively. Since the planned number of patients could not be enrolled, no efficacy conclusion can be drawn. The high rate of placebo response challenges clinical trials for SSHL and needs to be considered in future investigations. Trial registrations This study was registered in the EU Clinical Trials Register, EudraCT-No. 2012-000066-37 at 2012-07-02.

Vestibular and audiometric results after endolymphatic mastoid shunt surgery in patients with Menière's disease

PURPOSE

Treatment of Menière's Disease (MD) comprises an array of both non-destructive and destructive treatment options. In patients who are therapy-refractory to non-destructive medical treatment, endolymphatic mastoid shunt surgery (EMSS) is both recommended and debated controversially. The aim of this study was to investigate safety in terms of hearing, vestibular function, complication rate, and efficacy with regards to vertigo control of EMSS in patients with MD according to the current diagnostic criteria of 2015.

METHODS

Retrospective analysis of 47 consecutive patients with definite or probable MD with description of demographic parameters, pre- and postoperative MD treatment, pre- and postoperative audiometric (pure tone audiometry) and vestibular (caloric testing) results. The parameters were compared between patients with and without postoperative vertigo control.

RESULTS

31/47 patients (66.0%) had improved vertigo control postoperatively. Postoperative hearing and vestibular preservation were predominantly stable. No significant differences between patients with improved vertigo control and patients with no change or worse vertigo episodes were found. In the treatment refractory group, 4 patients required a revision EMSS and 6 a destructive MD treatment (5 gentamicin intratympanically, 1 labyrinthectomy). No peri- or postsurgical complications were reported.

CONCLUSIONS

EMSS was found to be beneficial in two thirds of the patients with definite or probable Morbus Menière and a safe procedure regarding hearing and vestibular preservation with no postoperative complications. Therefore, EMSS should be considered before inducing destructive treatment options, such as intratympanic gentamicin application or labyrinthectomy.

Subgroups in the treatment of nasal polyposis with dupilumab: A retrospective study

Dupilumab has been shown to be safe and effective in treating chronic rhinosinusitis with polyposis (CRSwNP). There is to this date no published data whether subgroups like patients with aspirin exacerbated respiratory disease (AERD), increased histologic eosinophilia or elevated blood eosinophil or IgE-levels benefit greater from dupilumab therapy. Moreover, there is no data comparing the efficacy of functional endoscopic sinus surgery (FESS) with dupilumab therapy. We conducted a retrospective chart review of all patients that were treated at a tertiary referral center for CRswNP with dupilumab. We also contacted the patients with a questionnaire to evaluate the efficacy of previous surgeries and dupilumab therapy by visual analogue scale (VAS) and the glasgow benefit inventory (GBI) as well as report on side effects. Overall, 75 patients were included in the study at hand that reported back 138 times. While dupilumab treatment was efficient, we found no systematic evidence of greater efficacy of dupilumab in patients with AERD, histologic eosinophilia or increased blood eosinophil or IgE-levels. All patients showed a considerable decrease in subjective burden of disease, objective smell tests and endoscopic findings. From the patients point of view, dupilumab therapy showed greater efficacy both in the VAS and the GBI overall and all subcategories but "social support." Dupilumab is efficient in treating CRSwNP; this effect is independent from disease characteristics like AERD, histologic eosinophilia, serum IgE-levels or eosinophil counts. There seems to be a group of patients that benefit greater from dupilumab therapy compared to FESS.

Low Dose Betahistine in Combination With Selegiline Increases Cochlear Blood Flow in Guinea Pigs

OBJECTIVE

Betahistine is frequently used in the pharmacotherapy for Menière's Disease (MD). Little is known about its mode of action and prescribed dosages vary. While betahistine had an increasing effect on cochlear microcirculation in earlier studies, low dose betahistine of 0.01 mg/kg bw or less was not able to effect this. Selegiline inhibits monoaminooxidase B and therefore potentially the breakdown of betahistine. The goal of this study was to examine whether the addition of selegiline to low dose betahistine leads to increased cochlear blood flow.

METHODS

Twelve Dunkin-Hartley guinea pigs were anesthetized, the cochlea was exposed and a window opened to the stria vascularis. Blood plasma was visualized by injecting fluoresceinisothiocyanate-dextrane and vessel diameter and erythrocyte velocity were evaluated over 20 minutes. One group received low dose betahistine (0.01 mg/kg bw) and selegiline (1 mg/kg bw) i.v. while the other group received only selegiline (1 mg/kg bw) and saline (0.9% NaCl) as placebo i.v.

RESULTS

Cochlear microcirculation increased significantly (P < .001) in guinea pigs treated with low dose betahistine combined with selegiline by up to 58.3 ± 38.7% above baseline over a period of up to 11 minutes. In one guinea pig, the increase was 104.6%. Treatment with Selegiline alone did not affect microcirculation significantly.

CONCLUSIONS

Low dose betahistine increased cochlear microcirculation significantly when combined with selegiline. This should be investigated in further studies regarding dose-effect relation in comparison to betahistine alone. Side effects, in particular regarding circulation, should be considered carefully in view of the clinical applicability of a combination therapy in patients with MD.

Factors influencing outcomes in selective neck dissection in 661 patients with head and neck squamous cell carcinoma

Background

Selective neck dissection (SND) is the surgical treatment of choice in squamous cell carcinoma of the head and neck (HNSCC) with suspected or manifest metastases in the cervical lymph nodes. For SND to be successful, treated lymph node levels should be selected according to anatomic considerations and the extent of the disease. Aim of this study was to identify neck dissection levels that had an impact on individual prognosis.

Methods

We conducted a retrospective review of SND as part of primary treatment of HNSCC. Overall survival (OS) and regional control rates (RCR) were calculated for all patients treated at one academic tertiary referral center.

Results

661 patients with HNSCC were included, 644 underwent ipsilateral and 319 contralateral SND. Average follow-up was 78.9 ± 106.4 months. 67 (10.1%) patients eventually developed nodal recurrence. Tumor sites were oral cavity (135), oropharynx (179), hypopharynx (118) and larynx (229). Tumor categories pT1–pT4a, and all clinical and pathological nodal categories were included. Multivariate analysis indicated improved OS rates for patients undergoing SND in ipsilateral levels I and V as well as level III contralaterally. Analysis for tumor origin showed that SND in ipsilateral level I showed significantly improved OS in HNSCC of the oral cavity.

Conclusion

The dissection of ipsilateral level I in oral cavity cancer was of particular relevance in our exploratory, retrospective analysis. To clarify the relevance for the determination of the extent of SND, this should be investigated prospectively in a more homogenous patient cohort.

Nasal Septal Perforation Closure by "Sandwich Grafts": Technique, Initial Results

Nasal septal perforation closure represents a considerable surgical challenge. Many techniques rely on the implantation of foreign materials that pose a persisting threat of infection. The authors have identified a reliable technique closing septal perforations by an autologous "sandwich graft." It is layered around a piece of auricular cartilage, covered with temporal fascia, thus emulating the physiological layers of the nasal septum. Finally, the prepared graft is then sewn into the perforation in an underlay technique and kept in place by septal splints for 4 weeks. The technique is easily feasible and strives to reconstruct the nasal as physiological as possible. The data obtained from a case series of 11 patients highlights the efficacy of the technique.

Lipedema in a male patient: report of a rare case - management and review of the literature

Objective: Lipedema is a relatively common yet debilitating and often misdiagnosed lipodystrophy that mainly affects females. Very little is known about the etiology and pathophysiology of the disease. However, due to its high preference for female patients, hormonal factors may contribute to the pathogenesis. Case: A 62-year-old male patient presented to the authors with painful swelling of the thighs. The patient had been treated elsewhere for lymphedema with subsequent disease progression. Lipedema stage IV was confirmed by clinical examination and ultrasound. The patient underwent three sessions of tumescence liposuction which was well tolerated. Later on, the patient reported great improvement in terms of complaints as well as disfigurement. Conclusion: The etiology and pathophysiology of lipedema remain unclear. However, the case at hand shows that lipedema may, albeit rare, also present in male patients. Moreover, we show that liposuction is efficient and safe in treating lipedema even in atypical cases.

Management of chronic rhinosinusitis with nasal polyps in Samter triad by low-dose ASA desensitization or dupilumab

Samter triad is a chronic condition where patients suffer from intolerance to aspirin, recurring nasal polyposis and bronchial asthma. Causative treatment is often hard. Potential approaches are the daily intake of acetylsalicylic acid (ASA), shunting arachidonic acid into the lipoxygenase pathway, and a subsequent habituation to this constant inflammatory stimulus. Alternatively, the paramount interleukins 4 and 13 may be antagonized by the monoclonal antibody dupilumab. Hence, we evaluated the daily intake of 100 mg ASA and systemic dupilumab (300 mg s.c. every 2 weeks) therapy in refractory patients for its efficacy and compliance.We conducted a retrospective chart review for the efficacy and compliance of both continuous ASA desensitization and systemic dupilumab therapy for refractory patients.Thirty-one patients were included in this retrospective chart review, mean follow-up was 20.4 ± 15.7 months. All patients underwent ASA desensitization. Twenty-one patients had eventually discontinued therapy after 5.8 ± 4.5 months; 11 for its side effects, 12 for its inefficacy. Twenty patients developed sinunasal complaints soon thereafter. Ten patients were still undergoing desensitization (mean duration 15.3 ± 15.7 months). These patients had a higher prevalence of concomitant anti-asthmatic medication. Seventeen refractory patients underwent systemic dupilumab therapy. After 6.4 ± 2.7 months of treatment, sinunasal outcome test (68.1 ± 13.9 vs 20.1 ± 13.9) and visual analogue scales of overall complaints (8.7 ± 0.9 vs 2.2 ± 1.5) as well as endoscopic findings and olfactory function (brief smell identification test; 3.5 ± 2.6 vs 8.6 ± 2.4) all improved significantly.A considerable number of patients with Samter triad discontinued ASA desensitization, equally for ineffectiveness or side effects. If desensitization is to be effective, special care needs to be taken in respect to concomitant anti-asthmatic medication. Dupilumab is highly effective and safe in treating refractory patients.

Cannabinoid Receptor 2 Agonism is Capable of Preventing Lipopolysaccharide Induced Decreases of Cochlear Microcirculation - A Potential Approach for Inner Ear Pathologies

HYPOTHESIS

The ability of JWH-133, an agonist at the cannabinoid receptor 2, to abrogate the effects of lipopolysaccharide on cochlear microcirculation was investigated.

BACKGROUND

Cochlear inflammation and subsequent impairment of microcirculation is part of numerous pathologies affecting inner ear function, including suppurative labyrinthitis, noise trauma, and sudden sensorineural hearing loss. One way of causing cochlear inflammation is exposing the cochlea to lipopolysaccharide, a bacterial endotoxin.

METHODS

Twenty Dunkin-hartley guinea pigs were divided into four groups of five animals each. Two groups received topic treatment with JWH-133 and two received treatment with placebo. One group that had been treated with JWH-133 and one with placebo were then exposed to lipopolysaccharide or placebo, respectively. Cochlear microcirculation was quantified before, in between and after treatments by in vivo fluorescence microscopy.

RESULTS

Significantly different changes in cochlear blood flow were only seen in the group that was treated with placebo and subsequently lipopolysaccharide. Every other group showed no significant change in cochlear blood flow.

CONCLUSION

JWH-133 is capable of abrogating the effects of lipopolysaccharide on cochlear microcirculation. It may therefore be clinical interest in treating numerous inflammation associated cochlear pathologies.

MicroRNA-182-5p and microRNA-205-5p as potential biomarkers for prognostic stratification of p16-positive oropharyngeal squamous cell carcinoma

BACKGROUND

MicroRNAs constitute promising biomarkers.

OBJECTIVE

The aim was to investigate diagnostic and prognostic implications of miR-182-5p and miR-205-5p in p16-positive and p16-negative oropharyngeal squamous cell carcinomas (OPSCCs).

METHODS

Expression of miR-182-5p, miR-205-5p were determined via quantitative real-time-PCR in fresh frozen tissues of 26 p16-positive, 19 p16-negative OPSCCs and 18 HPV-negative oropharyngeal controls. Associations between miRNA-expression, clinicopathological characteristics and prognosis were analyzed.

RESULTS

Higher miR-182-5p expression was associated with significant inferior disease-specific survival for p16-positive OPSCCs (HR = 1.98E+09, 95% CI 0-Inf; P= 0.028) and a similar trend was observed for p16-negative OPSCCs (HR = 1.56E+09, 95% CI 0-Inf; P= 0.051). Higher miR-205-5p expression was associated with an inferior progression-free survival (HR = 4.62, 95% CI 0.98-21.83; P= 0.034) and local control rate (HR = 2.18E+09, 95% CI 0-Inf; P= 0.048) for p16-positive OPSCCs.

CONCLUSIONS

Results indicate that miR-182-5p and miR-205-5p can further stratify patients with p16-positive OPSCC into prognostic groups.

Etiology, Management, and Outcome of Pediatric Epistaxis

OBJECTIVE

Epistaxis in children is one of the most common causes for seeking professional medical help. Patients may be treated by several disciplines with various approaches to pediatric epistaxis. We reviewed cases of pediatric epistaxis from an otorhinolaryngologist's point of view.

METHODS

A retrospective chart review was performed on all patients younger than 18 years presenting with epistaxis to the Department of Otorhinolaryngology at the University of Bonn, Germany.

RESULTS

Sixty episodes of epistaxis in 58 patients were included in the study. Mean age was 10.1 ± 4.5 years. In terms of risk factors, 3 patients had a hemorrhagic diathesis, 3 had taken medication that interfered with hemostasis, and 8 had a history of previous trauma, most of which was digital manipulation. Twenty-six patients did not need invasive therapy. Twenty-six patients received cauterization to control the bleeding, and 4 patients needed surgery. The necessity for surgery was mainly noncooperation.

CONCLUSIONS

Epistaxis in children is seldom serious. However, hemorrhagic diathesis needs to be kept in mind as a potential cause of epistaxis. In most cases, careful instruction of the patients and the relatives concerning nasal mucosal care is sufficient. If cauterization is necessary, silver nitrate coagulation should be preferred over electrocoagulation.

Functional results with active middle ear implant or semi-implantable bone conduction device in patients with comparable hearing loss

OBJECTIVE

In patients with conductive (CHL) or mixed hearing loss (MHL), hearing rehabilitation with an implantable hearing system, active middle ear implant (AMEI) or a semi-implantable bone-conduction device (SIBCD), is an option when conventional hearing aids are insufficient, or patients are unable to wear them.

DESIGN

Retrospective analysis of 20 consecutive patients (24 implants) with a comparison of demographic characteristics and audiometric results (air-bone gap = ABG, effective hearing gain = EHG, functional hearing gain = FHG, Freiburg Monosyllabic Test in quiet, Oldenburg Sentence Test in noise = OLSA).

STUDY SAMPLE

Patients, eligible for both devices, who received either AMEI or SIBCD due to CHL or MHL.

RESULTS

Analysis showed no significant differences in post-operative functional hearing results between the group of AMEI vs. SIBCD (ABG-reduction: 31.6 ± 12.4 dB HL vs. 28.0 ± 11.8 dB HL; p = 0.702; EHG: -1.6 ± 7.7 dB HL vs. -1.2 ± 4.2 dB HL; p = 0.090; FHG: 33.4 ± 12.6 dB HL vs. 26.1 ± 11.7 dB HL; p = 0.192; Freiburg: 83.0 ± 15.6% vs. 83.6 ± 14.2%; Freiburg-improvement: 57.7 ± 26.8% vs. 68.2 ± 19.7%; p = 0.294; OLSA: -2.7 ± 3.0 SNR vs. -1.4 ± 3.6 SNR; OLSA-improvement: 2.6 ± 2.1 dB vs. 3.7 ± 2.8 dB; p = 0.323). Four patients had the AMEI explanted due to insufficient functioning and later received a SIBCD.

CONCLUSIONS

Due to more challenging anatomical conditions, a surgical technique for the AMEI is more complex. However, functional results are comparable to the SIBCD. Therefore, proper patient counselling and cautious choice of the device are mandated before surgery.

Classification of endonasal HHT lesions using digital microscopy

BACKGROUND

Recurrent spontaneous epistaxis is the most common clinical manifestation and the most debilitating symptom in hereditary haemorrhagic telangiectasia (HHT) patients. To this date, there exist only a classification of HHT patients by different genetic mutations. There is no standard classification for the mucocutaneous endonasal manifestations of HHT. The aim of the present study was to document the variety of endonasal HHT lesions using digital microscopy and to propose a clinical classification.

METHODS

We recorded the endonasal HHT lesions of 28 patients using a digital microscope. We reconstructed the 3D images und videos recorded by digital microscope afterwards and classified the endonasal lesions of HHT in two classes: Grade A, presence of only flat telangiectasias in the mucosa level and Grade B, (additional) presence of raised berry or wart-like telangiectasia spots. We investigated also Haemoglobin level by routine laboratory procedures, plasma VEGF level by ELISA, Severity of epistaxis by epistaxis severity score (ESS) and quality of life by a linear visual analogue scale (VAS).

RESULTS

We found a higher quality of life and a lower severity of epistaxis in Grade A patients in comparison to Grade B patients. No difference in plasma VEGF level and in Haemoglobin between Grad A patients and Grade B patients could be detected. Plasma VEGF levels showed no gender specific differences. It could also not be correlated to the extranasal manifestation.

CONCLUSION

The classification for endonasal manifestation of HHT proposed in this study indicates severity of epistaxis und quality of life. Digital microscopy with the ability of 3D reconstruction of images presents a useful tool for such classifications. The classification of endonasal HHT lesions using digital microscopy allows to evaluate the dynamic of HHT lesions in the course of time independent of examiner. This allows also to evaluate the efficacy of the different treatment modalities by dynamic of HHT lesions. Moreover digital microscopy is very beneficial in academic teaching of rare diseases.

The course of subjective and objective chemosensory dysfunction in hospitalized patients with COVID-19: a 6-month follow-up

Purpose

It has been established that the infection with SARS-CoV-2 may cause an impairment of chemosensory function. However, there is little data on the long-term effects of SARS-CoV-2 infection on chemosensory function.

Methods

Twenty three SARS-CoV-2-positive patients diagnosed in spring 2020 with subjective hyposmia (out of 57 positive patients, 40.3%) were compared to SARS-CoV-2-positive patients without hyposmia (n = 19) and SARS-CoV-2-negative patients (n = 14). Chemosensory function was assessed by the Brief Smell Identification Test (BSIT), Taste Strips (TS), Visual Analogue Scales (VAS), and the SNOT-22. The initial cohort with hyposmia were also examined at 8 weeks and 6 months after initial examination.

Results

There were no differences between the SARS-CoV-2-positive cohort without hyposmia and negative controls in terms of BSIT (8.5 ± 2.6 vs. 10.2 ± 1.8), TS (3.4 ± 0.6 vs. 3.9 ± 0.3) or VAS (2.1 ± 1.3 vs. 1.1 ± 0.5); yet the SNOT-22 was significantly elevated (27.7 ± 11.2 vs. 16.4 ± 10.8). The SARS-CoV-2-positive group with hyposmia performed significantly poorer in BSIT (4.0 ± 1.7 vs. 8.5 ± 2.6/10.2 ± 1.8), TS (2.6 ± 1.3 vs. 3.4 ± 0.6/3.9 ± 0.3), and VAS (7.9 ± 2.2 vs. 2.1 ± 1.3/1.1 ± 0.5) compared to both control groups. At week 8 and month 6 control, six and five patients, respectively, still suffered from subjectively and objectively impaired chemosensory function. The other patients had recovered in both respects.

Conclusion

SARS-CoV-2 patients with subjectively impaired chemosensory function regularly perform poorly in objective measurements. About 70% of patients suffering from olfactory dysfunction in SARS-CoV-2 quickly recover—the rest still suffers from considerable impairment 6 months after infection.

Cancer Stem Cell Markers in Squamous Cell Carcinomas of the Salivary Glands

BACKGROUND

Cancer stem cells (CSC) are cells that exhibit stem cell properties and are pivotal in tumor biology. CSC markers have been described for many tumorous entities. However, to this date, there is no data on CSC markers in respect to squamous cell carcinomas (SCC) of the salivary glands.

METHODS

Histologic samples from patients with salivary gland SCCs were stained for CSC markers (ALDH-1/BMI-1/SOX-2/CD-44/vimentin) and divided into high and low expression subgroups. These were then correlated with tumor and patient characteristics as well as overall survival (OS), disease-specific survival, recurrence-free survival and local control rates (LCR) after 3 and 5 years.

RESULTS

Overall, 31 samples were included. CD-44 and ALDH-1 expression were associated with tumor origin (metastatic/primary disease, p = 0.048 and p = 0.011, respectively). Strong BMI-1 expression was associated with poorer OS (62.9 vs. 27.3%, p = 0.029), strong SOX-2 expression was associated with poorer LCR (62.5 vs. 21.9%, p = 0.007).

CONCLUSION

CD-44 and ALDH-1 may be useful in differentiating between primary SCCs and metastatic disease. BMI-1 and SOX-2 are correlated with poorer prognosis.

Intratympanal administration of lidocaine in the management of Ménière's Disease

BACKGROUND

Ménière's Disease (MD) is a chronic condition where patients suffer recurrent vertigo attacks. Evidence for treatment concepts are to this date low.

AIMS/OBJECTIVE

To evaluate the therapeutic effect of intratympanic lidocaine injections to reduce the number of attacks.

METHODS

Twenty patients diagnosed with definitive MD that were treated with 34 intratympanic lidocaine injections were included. Main outcome measures were the number of vertigo attacks in the previous four weeks, the attack free period and the subjective improvement of the condition.

RESULTS

Mean follow up after first lidocaine injection was 25.3 months (±22.2; range 1.9-79.7). Patients expressed subjective improvement in overall situation, vertigo, and aural fullness. The number of vertigo attacks before each assessment decreased from 7.1 (±5.9; range 2-20) per months at baseline to 1.9 (±3.8; range 0-15). 25% of the patients suffered no further attacks, the other patients had an average attack free period of 7.8 months (±15.4; range 0.2-58.4). Hearing thresholds remained unaffected. Repetitive injections proved effective.

CONCLUSION AND SIGNIFICANCE

Intratympanic lidocaine is an effective nonsurgical and non-ablative therapy for MD. When patients experience an increase of attacks repetitive injections promise improvement.

Lipopolysaccharide decreases cochlear blood flow dose dependently in a guinea pig animal model via TNF signaling

OBJECTIVE

To evaluate the effect of Lipopolysaccharide (LPS), a bacterial endotoxin on cochlear microcirculation, and its mode of action.

METHODS

Twenty-five Dunkin-Hartley guinea pigs were divided into five groups of five animals each. After surgical preparation, cochlear microcirculation was quantified by in vivo fluorescence microscopy. Placebo or LPS (1 mg, 10 µg, and 100 ng) was applied topically, and microcirculation was measured before and twice after application. A fifth group was pretreated with etanercept, a tumor necrosis factor (TNF) antagonist, and afterward the lowest LPS concentrations that yielded significant results (10 µg) were applied.

RESULTS

In the groups that had been treated with 1 mg and 10 µg LPS, a significant drop in cochlear microcirculation was observed after 30 (.791 ± .089 Arbitrary Units (AU), compared to baseline, and .888 ± .071AU) and 60 (.756 ± .101 AU and .817 ± .124 AU, respectively) minutes. The groups that had been treated with 100 ng LPS and that had been pretreated with etanercept showed no significant change in cochlear blood flow compared to placebo.

CONCLUSION

Lipopolysaccharide shows a dose-dependent effect on cochlear microcirculation; this effect can already be observed after 30 min. Pretreatment with etanercept can abrogate this effect, indicating that TNF mediates the effect of LPS on cochlear microcirculation.

Cancer stem cell markers in adenocarcinoma of the salivary glands - reliable prognostic markers?

Purpose

Adenocarcinoma of the salivary glands is of low incidence and a broad range of histopathological subtypes. Cancer stem cell markers (CSC) might serve as novel prognostic parameters. To date, only a few studies examined the expression of CSC in adenocarcinoma of the salivary glands with diverging results. To further investigate the reliability in terms of prognostic value, a histopathological analysis of CSCs on a cohort of patients with adenocarcinomas of the major salivary glands was performed.

Methods

Tumor samples of 40 consecutive patients with adenocarcinoma of the major salivary gland treated with curative intend at one tertiary center were stained with the CSCs ALDH1, BMI-1, CD44, Nanog, and SOX2. Expression of these markers was correlated with clinicopathological parameters and survival estimates.

Results

Correlation of high expression of ALDH1 with higher grading (p < 0.001) and high expression of CD44 with the localization of the neoplasm (p = 0.05), larger tumor size (p = 0.006), positive pN-category (p = 0.023), and advanced UICC stage (p = 0.002) was found. Furthermore, high expression of SOX2 correlated with a negative perineural invasion (p = 0.02). No significant correlation of any investigated marker with survival estimates was observed.

Conclusion

In conclusion, our study did not find a significant correlation of the investigated CSCs with survival estimates in adenocarcinoma of the major salivary glands. Recapitulating the results of our study in conjunction with data in the literature, the CSCs ALDH1, BMI-1, CD44, Nanog, and SOX2 do not seem to serve as reliable prognostic parameters in the treatment of adenocarcinoma of the salivary glands.

Electronic supplementary material

The online version of this article (10.1007/s00405-020-06389-7) contains supplementary material, which is available to authorized users.

Role of cancer stem cell markers ALDH1, BCL11B, BMI-1, and CD44 in the prognosis of advanced HNSCC

Purpose

Cancer stem cells (CSCs) are held accountable for the progress of head and neck squamous cell carcinoma (HNSCC). In the presented study, the authors evaluated the prognostic value of CSC markers in two particular HNSCC cohorts.

Methods

This two cohort study consisted of 85 patients with advanced stage HNSCC, treated with primary radio(chemo)therapy (pRCT), and 95 patients with HNSCC, treated with surgery and partially adjuvant radio(chemo)therapy. Overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) were assessed. Samples were assessed for the expression of different molecular stem cell markers (ALDH1, BCL11B, BMI‑1, and CD44).

Results

In the pRCT cohort, none of the baseline patient and tumor features exhibited a statistically significant relation with survival in either the cohort or the human papillomavirus (HPV)-stratified subcohorts. High expression of BMI‑1 significantly decreased OS and DFS, while high expression of CD44 decreased all modes of survival. Multivariate analysis showed significant prognostic influence for all tested CSC markers, with high BMI‑1 and CD44 decreasing survival (BMI-1: OS, DFS, DSS; CD44: OS, DFS) and high ALDH1 and BCL11B showing a beneficial effect on survival (ALDH1: OS, DFS; BCL11B: OS, DSS). In the surgical cohort, classical prognosticators such as HPV status, R1 resection, and nodal status in HPV-negative HNSCC played a significant role, but the tested CSC markers showed no significant effect on prognosis.

Conclusion

Although validation in independent cohorts is still needed, testing for CSC markers in patients with advanced or late stage HNSCC might be beneficial, especially if many comorbidities exist or disease is irresectable. The findings might guide the development and earlier use of targeted therapies in the future.

Electronic supplementary material

The online version of this article (10.1007/s00066-020-01653-5) contains supplementary material, which is available to authorized users.

Safety and Efficacy of Blue Light Laser Treatment in Hereditary Hemorrhagic Telangiectasia

BACKGROUND AND OBJECTIVES

Hereditary hemorrhagic telangiectasia (HHT) is a hereditary condition that is associated with arteriovenous malformations. A common site for these malformations is the nasal mucosa, which is associated with severe epistaxis and debilitation for affected patients. We evaluated the efficacy and safety of blue light laser technology in treating these endonasal manifestations in a retrospective chart analysis. Additionally, we compared blue light laser technology to bipolar coagulation in an animal model.

STUDY DESIGN/MATERIALS AND METHODS

We performed a retrospective chart analysis of all patients that were diagnosed with HHT and received endonasal blue light laser treatment between 10/2017 and 04/2019. In addition, we performed bipolar or blue light laser coagulation of all macroscopically visible vessels on thyroid gland lobes (n = 4) from Dunkin-Hartley Guinea Pigs. Hematoxylin-eosin (HE) staining was then used to visualize depth and area of coagulation surrounding these vessels.

RESULTS

One hundred and fifty-one treatments in 23 patients were analyzed. Under regular blue light laser treatment, quality of life (QOL), indicated on a visual analog scale from 1 to 10, gradually increased significantly from 5.6 ± 0.5 (before the first treatment) to 7.5 ± 0.9 (after the second treatment). Following this, QOL remained steady throughout additional treatments. Adverse effects were not recorded. HE staining showed that coagulation depth (162 ± 56 vs. 586 ± 192 µm) and area (74 ± 35 vs. 1015 ± 449 µm² ) were significantly lower after laser treatment.

CONCLUSION

Blue light laser therapy is safe and efficient in treating HHT. Damage to the surrounding tissue is significantly lower compared with bipolar coagulation. © 2020 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals LLC.

Clinical features of sarcoidosis patients presenting with head and neck manifestations - a two-center retrospective study and proposal of a diagnostic algorithm for the otorhinolaryngologist

Background and Aims: We aimed to investigate the clinical characteristics of patients presenting with sarcoidosis of the head and neck as the initial manifestation and to provide recommendations for the diagnostic work-up for the practicing otorhinolaryngologist.Material and Methods: We performed a retrospective cohort study at two university medical centers in Germany. Patients with a histopathologically confirmed diagnosis of sarcoidosis treated in the otorhinolaryngology departments were analyzed.Results: We identified 62 patients (2003-2016). In total, 85.4% (n = 53) of patients received the initial diagnosis of sarcoidosis during their ENT treatment. Sarcoidosis was detected in the lymph nodes in 42.3% (n = 30) of the patients; 57.7% had extra-lymphatic manifestations. Fifteen patients (24.2%) showed pulmonary involvement. 30.6% (n = 19) were treated with oral glucocorticoids (GC) alone, three patients with GC and methotrexate, one patient initially received a combination of GC and azathioprine, one patient rejected the recommended treatment.Conclusions: Sarcoidosis should be considered as a differential diagnosis in patients presenting with head and neck symptoms. The most frequent presenting symptoms were cervical lymphadenopathy and affection of the paranasal sinuses. Therefore, otorhinolaryngologists should be aware of sarcoidosis and help guide referral strategies as they may be the first physicians treating these patients.

Benefit of postoperative radiotherapy for early tumors with single ipsilateral lymph node metastasis

OBJECTIVES/HYPOTHESIS

Indication for postoperative radiotherapy in patients with locally circumscribed tumors (pT1-pT2) and a single ipsilateral lymph node metastasis (pN1) is debatable. The aim of this study was to evaluate the oncological long-term outcome of patients with pT1-pT2 pN1 squamous cell carcinoma (SCC) of the oral cavity, the oropharynx, and the hypopharynx without extracapsular spread (ECS) after a margin-negative surgical resection, who either received or did not receive postoperative (chemo)radiotherapy.

STUDY DESIGN

Retrospective case series.

METHODS

The oncological outcome of patients with pT1-pT2 pN1 SCC without ECS was evaluated retrospectively. All patients underwent primary tumor resection that included transoral laser microsurgery and neck dissection at an academic tertiary referral center.

RESULTS

Of 65 identified patients treated between 1986 and 2015 (18 oral cavity, 30 oropharynx, 17 hypopharynx), 21 (32%) received postoperative radiotherapy, and 44 (68%) were treated by surgery alone. The group of patients receiving postoperative treatment showed a significantly superior 5-year disease-specific (94.4% vs. 73.2%, P = .029) and recurrence-free survival (85.2% vs. 43.2%, P = .002), as well as a higher local control rate (90.2% vs. 64.9%, P = .042). The overall survival was 71.4% vs. 62.6% (P = .53). The mean follow-up was 80.7 months.

CONCLUSIONS

Patients with locally circumscribed carcinomas and a single ipsilateral ECS-negative lymph node metastasis seem to benefit from postoperative radiotherapy.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:E530-E538, 2020.

Reconstruction of the skull base in spontaneous rhinoliquorrhea

Objective/Hypothesis: Spontaneous rhinoliquorrhea often occurs due to defects of the skull base. It is often misinterpreted as rhinitis and is surgically the most difficult rhinoliquorrhea entity to close. Methods: We conducted a retrospective chart analysis of patients that were diagnosed with spontaneous rhinoliquorrhea at the University Hospital Bonn between 2001 and 2017. Results: Overall, twelve patients were included in this study. On average, the time between occurrence of nasal discharge and diagnoses of rhinoliquorrhea was 123 days. In ten patients, the localization of the skull base defect could be localized by computed tomography or MRI cisternography. Ten patients underwent surgery, of which 9 remained recurrence free. One patient underwent revision surgery and from thereon was recurrence free. Conclusion: Spontaneous rhinoliquorrhea still remains a diagnostic and therapeutic challenge. Whenever persistent watery nasal discharge appears in a patient, rhinoliquorrhea must be considered. Endoscopic surgical reconstruction of the skull base is the therapeutic gold standard and should be attempted as soon as the diagnosis is secured.

MicroRNA expression patterns in oral squamous cell carcinoma: hsa-mir-99b-3p and hsa-mir-100-5p as novel prognostic markers for oral cancer

BACKGROUND

MicroRNAs (miRNA) recently evolved as potential cancer biomarkers. Therefore, the aim of the present study was to evaluate the prognostic impact of eight miRNAs connected to oral squamous cell carcinoma (OSCC).

METHOD

Expression levels of hsa-mir-21-5p, hsa-mir-29b-3p, hsa-mir-31-5p, hsa-mir-99a-5p, hsa-mir-99b-3p, hsa-mir-100-5p, hsa-mir-143-3p and hsa-mir-155-5p were analyzed in tumor tissue (n = 36) and healthy oral mucosal tissue (n = 17) and correlated with clinical variables. Results of the study cohort were validated in an OSCC cohort of The Cancer Genome Atlas.

RESULTS

Increased hsa-mir-99b-3p expression level showed a tendency toward advanced tumor stages, and high levels of hsa-mir-100-5p expression were associated with extracapsular extension. While a high expression level of hsa-mir-99b-3p was associated with better survival, a high expression level of hsa-mir-100-5p was correlated with a poorer survival in the study cohort.

CONCLUSION

Our results indicate that hsa-mir-99b-3p and hsa-mir-100-5p may serve as novel prognostic biomarkers in OSCC.

Transoral laser microsurgery for treatment of oropharyngeal cancer in 368 patients

BACKGROUND

Oncological and functional outcome of transoral laser microsurgery (TLM) for primary treatment of oropharyngeal cancer was examined using a multimodal treatment concept.

METHODS

A total of 368 patients with oropharyngeal squamous cell carcinoma (pT1-4, pN0-2, M0) underwent TLM +/- neck dissection (85%), +/- (chemo)radiotherapy (57%). The majority of patients had advanced stage III and IVa disease (79%).

RESULTS

Five-year Kaplan-Meier estimates for local control were 83.5% for pT1, 74.1% for pT2, 77.3% for pT3, and 76.0% for pT4a tumors. Five-year estimates of overall, disease-specific, and recurrence-free survival for stage I were 76.0%, 92.8%, and 69.1%; for stage II 71.1%, 85.7%, and 49.6%; for stage III 61.7%, 72.5%, and 58.8%; and for stage IVa 57.3%, 73.7%, and 63.9%, respectively. Postoperative (chemo)radiotherapy improved the outcome for advanced disease. p16-positive tumors had superior survival estimates. Overall, 93.5% maintained regular oral nutrition without feeding tube dependency.

CONCLUSION

Primary TLM in multimodal concepts of treatment offers good oncologic outcome even for advanced-stage oropharyngeal cancer.

Cochlear Capillary Pericytes

Capillary pericytes in the cochlea of mammals are-compared to pericytes in other tissues, like the CNS-relatively poorly researched. To begin with, there is still a considerable debate as to whether the very last precapillary arterioles should-due to their contractile properties-may be considered to be pericytes.However, cochlear capillary pericytes have shifted into the center of attention in the past decade. Most mammals show a considerable number of pericytes in the stria vascularis of the cochlea-up to 1300 in a mouse alone. This high number may be explained by the observation that cochlear capillary pericytes may be differentiated into different subgroups, depending on the immune markers that are expressed by them. Corresponding with these subpopulations, cochlear pericytes fulfill three core functions in the physiology of the cochlea: Formation of the intrastrial blood-fluid barrier-Pericytes monitor the ion, fluid, and nutrient household and aid in the homeostasis thereof. Regulation of cochlear blood flow-By contraction on relaxation, pericytes contribute to the regulation of cochlear blood flow, a paramount function parameter of the cochlea. Immune response-Pericytes actually contribute to the immune response in inflammation of the cochlea. Due to these central roles in the physiology of the cochlea, pericytes actually play a major role in numerous cochlear pathologies, including, but not limited to, sudden sensorineural hearing loss, acoustic trauma, and inflammation of the cochlea.

Management and outcome of epistaxis under direct oral anticoagulants: a comparison with warfarin

BACKGROUND

Epistaxis is one of the more common reasons for emergency room visits. The main risk factor for epistaxis is anticoagulant therapy. Until recently, the main culprit was oral intake of a vitamin K antagonist, such as warfarin, which has a number of side effects. Even more recently, several direct oral anticoagulants, rivaroxaban and dabigatran, have been approved for use. We investigated the possible differences between treatment of epistaxis with direct oral anticoagulants and vitamin K antagonists.

METHODS

We conducted a retrospective cohort study at a tertiary referral center in Germany. All patients who were admitted within a 1-year period were included. Patient files were used to obtain the information.

RESULTS

Overall, 677 patients were included in our study. Of these, 159 had been treated with vitamin K antagonists and 49 with direct oral anticoagulants. There were no significant differences in terms of age (p = 0.592), sex (p = 0.372), vital signs, bloodwork, or location of bleeding (p = 0.372). Management of epistaxis between the groups was also comparable (p = 0.399), with similar hospital admission rates (37.1% vs 24.5%; p = 0.145) and duration of stay (3.5 ± 2.1 days vs 3.8 ± 3.3 days; p = 0.650).

CONCLUSION

We found no evidence to suggest epistaxis is more severe or requires more invasive therapy in patients given direct oral anticoagulants. A significant proportion of patients on vitamin K antagonists were not within the target range for international normalized ratio, highlighting one of the main issues with oral anticoagulation by vitamin K antagonists.

Management and Follow-up Results of Salivary Fistulas Treated With Botulinum Toxin

OBJECTIVES/HYPOTHESIS

Salivary fistulas are a common minor complication of parotid surgery. botulinum toxin has repeatedly been reported to be an adequate treatment of this entity. To date, there is little scientific evidence for clinical decision making after appearance of a salivary fistula.

STUDY DESIGN

Retrospective chart analysis of 16 patients who had been treated with botulinum toxin for salivary fistula.

METHODS

All patients who had been treated for salivary fistula at a tertiary referral hospital from 2010 to 2016 were included. Patient files were used to obtain characteristics of patients, treatment, and follow-up.

RESULTS

Sixteen patients with salivary fistula received 27 injections of botulinum toxin. Nine patients required one injection for the fistula to heal, five patients needed two injections, and one patient needed three and four injections, respectively. No patient underwent additional surgery or radiotherapy. We observed no adverse effects in any patient treated with botulinum toxin.

CONCLUSIONS

In most cases of salivary fistula, injections of botulinum toxin are a valid treatment. If the initial injection is not successful, injections may be repeated once. Otherwise, revision surgery should be considered. In general, treatment with botulinum toxin should be commenced in an earlier stage and with higher dosages.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:403-408, 2019.

Cochlear Pericytes Are Capable of Reversibly Decreasing Capillary Diameter In Vivo After Tumor Necrosis Factor Exposure

OBJECTIVE

The aim of this work was to evaluate the effect of tumor necrosis factor (TNF) and its neutralization with etanercept on the capability of cochlear pericytes to alter capillary diameter in the stria vascularis.

METHODS

Twelve Dunkin-Hartley guinea pigs were randomly assigned to one of three groups. Each group was treated either with placebo and then placebo, TNF and then placebo, or TNF and then etanercept. Cochlear pericytes were visualized using diaminofluorescein-2-diacetate and intravasal blood flow by fluorescein-dextrane. Vessel diameter at sites of pericyte somas and downstream controls were quantified by specialized software. Values were obtained before treatment, after first treatment with tumor necrosis factor or placebo and after second treatment with etanercept or placebo.

RESULTS

Overall, 199 pericytes in 12 animals were visualized. After initial treatment with TNF, a significant decrease in vessel diameter at sites of pericyte somas (3.6 ±4.3%, n = 141) compared with placebo and downstream controls was observed. After initial treatment with TNF, the application of etanercept caused a significant increase (3.3 ±5.5%, n = 59) in vessel diameter at the sites of pericyte somata compared with placebo and downstream controls.

CONCLUSION

We have been able to show that cochlear pericytes are capable of reducing capillary diameter after exposition to TNF. Moreover, the reduction in capillary diameter observed after the application of TNF is revertible after neutralization of tumor necrosis factor by the application of etanercept. It seems that contraction of cochlear pericytes contributes to the regulation of cochlear blood flow.

Histaminergic H3-Heteroreceptors as a Potential Mediator of Betahistine-Induced Increase in Cochlear Blood Flow

OBJECTIVE

Betahistine is a histamine-like drug that is considered beneficial in Ménière's disease by increasing cochlear blood flow. Acting as an agonist at the histamine H1-receptor and as an inverse agonist at the H3-receptor, these receptors as well as the adrenergic α2-receptor were investigated for betahistine effects on cochlear blood flow.

MATERIALS AND METHODS

A total of 54 Dunkin-Hartley guinea pigs were randomly assigned to one of nine groups treated with a selection of H1-, H3- or α2-selective agonists and antagonists together with betahistine. Cochlear blood flow and mean arterial pressure were recorded for 3 min before and 15 min after infusion.

RESULTS

Blockage of the H3- or α2-receptors caused a suppression of betahistine-mediated typical changes in cochlear blood flow or blood pressure. Activation of H3-receptors caused a drop in cochlear blood flow and blood pressure. H1-receptors showed no involvement in betahistine-mediated changes of cochlear blood flow.

CONCLUSION

Betahistine most likely affects cochlear blood flow through histaminergic H3-heteroreceptors.

Etanercept Prevents Decrease of Cochlear Blood Flow Dose-Dependently Caused by Tumor Necrosis Factor Alpha

Objectives:

Tumor necrosis factor alpha (TNF-alpha) is a mediator of inflammation and microcirculation in the cochlea. This study aimed to quantify the effect of a local increase of TNF-alpha and study the effect of its interaction with etanercept on cochlear microcirculation.

Methods:

Cochlear lateral wall vessels were exposed surgically and assessed by intravital microscopy in guinea pigs in vivo. First, 24 animals were randomly distributed into 4 groups of 6 each. Exposed vessels were superfused repeatedly either with 1 of 3 different concentrations of TNF-alpha (5.0, 0.5, and 0.05 ng/mL) or with placebo (0.9% saline solution). Second, 12 animals were randomly distributed into 2 groups of 6 each. Vessels were pretreated with etanercept (1.0 μg/mL) or placebo (0.9% saline solution), and then treated by repeated superfusion with TNF-alpha (5.0 ng/mL).

Results:

TNF-alpha was shown to be effective in decreasing cochlear blood flow at a dose of 5.0 ng/mL (p < 0.01, analysis of variance on ranks). Lower concentrations or placebo treatment did not lead to significant changes. After pretreatment with etanercept, TNF-alpha at a dose of 5.0 ng/mL no longer led to a change in cochlear blood flow.

Conclusions:

The decreasing effect that TNF-alpha has on cochlear blood flow is dose-dependent. Etanercept abrogates this effect.

Betahistine exerts a dose-dependent effect on cochlear stria vascularis blood flow in guinea pigs in vivo

OBJECTIVE

Betahistine is a histamine H(1)-receptor agonist and H(3)-receptor antagonist that is administered to treat Menière's disease. Despite widespread use, its pharmacological mode of action has not been entirely elucidated. This study investigated the effect of betahistine on guinea pigs at dosages corresponding to clinically used doses for cochlear microcirculation.

METHODS

Thirty healthy Dunkin-Hartley guinea pigs were randomly assigned to five groups to receive betahistine dihydrochloride in a dose of 1,000 mg/kg b. w. (milligram per kilogram body weight), 0.100 mg/kg b. w., 0.010 mg/kg b. w., 0.001 mg/kg b. w. in NaCl 0.9% or NaCl 0.9% alone as placebo. Cochlear blood flow and mean arterial pressure were continuously monitored by intravital fluorescence microscopy and invasive blood pressure measurements 3 minutes before and 15 minutes after administration of betahistine.

RESULTS

When betahistine was administered in a dose of 1.000 mg/kg b. w. cochlear blood flow was increased to a peak value of 1.340 arbitrary units (SD: 0.246; range: 0.933-1.546 arb. units) compared to baseline (p<0.05; Two Way Repeated Measures ANOVA/Bonferroni t-test). The lowest dosage of 0.001 mg/kg b. w. betahistine or NaCl 0.9% had the same effect as placebo. Nonlinear regression revealed that there was a sigmoid correlation between increase in blood flow and dosages.

CONCLUSIONS

Betahistine has a dose-dependent effect on the increase of blood flow in cochlear capillaries. The effects of the dosage range of betahistine on cochlear microcirculation corresponded well to clinically used single dosages to treat Menière's disease. Our data suggest that the improved effects of higher doses of betahistine in the treatment of Menière's disease might be due to a corresponding increase of cochlear blood flow.