Performance of ear canal sound measurements in detecting dural arteriovenous fistulas.

OBJECTIVE: Patients with pulsatile tinnitus (PT) are often referred for digital subtraction angiography (DSA) to exclude cranial dural arteriovenous fistula (DAVF). Because DSA is not without risk, the authors studied the sensitivity and specificity of an automated detection algorithm that analyses external ear canal sound measurements to evaluate the presence of DAVF in PT patients. METHODS: Between 2015 and 2021, external ear canal sound measurements of 72 PT patients were collected prospectively at our tertiary tinnitus clinic preceding referral of these patients to the neurosurgical department for counseling about DSA. The measurements were analyzed with an algorithm that objectifies a pulsatile sound as a PT coherence index (PTCI) per frequency band. RESULTS: Ultimately, DSA was performed in 49 PT patients. DAVF was revealed in 15 patients (31%). PTCI cutoff values of 0.7 (at 250 Hz) and 0.6 (at 1000 Hz) resulted in sensitivity of 100% (78%-100%) and specificities of 62% (44%-78%) and 68% (49%-83%), respectively, for detecting DAVF on DSA. CONCLUSIONS: Analysis of external ear canal sound measurements in PT patients showed 100% sensitivity for detecting DAVF on DSA. This analysis can potentially be used as a screening tool to help clinicians and PT patients to decide on the necessity of DSA. Retrospectively, the use of sound measurement in our cohort would have narrowed the indication for DSA to 23 of 49 cases (47%) without missing a DAVF.

Performance of an Automated Detection Algorithm to Assess Objective Pulsatile Tinnitus.

OBJECTIVES: In this paper we describe an automated detection algorithm that objectively detects pulsatile tinnitus (PT) and investigate its performance. DESIGN: Sound measurements were made with a sensitive microphone placed in the outer ear canal in 36 PT-patients referred to our tertiary clinic, along with a registration of the heart rate. A novel algorithm expressed the coherence between the recorded sound and heart rate as a pulsatility index. This index was determined for 6 octave bands of the recorded sound. We assessed the performance of the detection algorithm by comparing it with the judgement of 3 blinded observers. RESULTS: The algorithm showed good agreement compared with the majority judgement of the blinded observers (ROC AUC 0.83). Interobserver reliability for detecting PT in sound recordings by the three blinded observers was substantial (Fleiss's κ=0.64). CONCLUSIONS: The algorithm may be a reliable alternative to subjective assessments of in-canal sound measurements in PT-patients, thus providing clinicians with an objective measure to differentiate between subjective and objective pulsatile tinnitus.

Revealing Unforeseen Diagnostic Image Features With Deep Learning by Detecting Cardiovascular Diseases From Apical 4-Chamber Ultrasounds.

Background With the increase of highly portable, wireless, and low-cost ultrasound devices and automatic ultrasound acquisition techniques, an automated interpretation method requiring only a limited set of views as input could make preliminary cardiovascular disease diagnoses more accessible. In this study, we developed a deep learning method for automated detection of impaired left ventricular (LV) function and aortic valve (AV) regurgitation from apical 4-chamber ultrasound cineloops and investigated which anatomical structures or temporal frames provided the most relevant information for the deep learning model to enable disease classification. Methods and Results Apical 4-chamber ultrasounds were extracted from 3554 echocardiograms of patients with impaired LV function (n=928), AV regurgitation (n=738), or no significant abnormalities (n=1888). Two convolutional neural networks were trained separately to classify the respective disease cases against normal cases. The overall classification accuracy of the impaired LV function detection model was 86%, and that of the AV regurgitation detection model was 83%. Feature importance analyses demonstrated that the LV myocardium and mitral valve were important for detecting impaired LV function, whereas the tip of the mitral valve anterior leaflet, during opening, was considered important for detecting AV regurgitation. Conclusions The proposed method demonstrated the feasibility of a 3-dimensional convolutional neural network approach in detection of impaired LV function and AV regurgitation using apical 4-chamber ultrasound cineloops. The current study shows that deep learning methods can exploit large training data to detect diseases in a different way than conventionally agreed on methods, and potentially reveal unforeseen diagnostic image features.

Changes in Tinnitus by Cochlear Implantation: A Parametric Study of the Effect of Single-Electrode Stimulation.

INTRODUCTION: While cochlear implantation may have a positive effect on tinnitus, it is not effective in reducing tinnitus in all patients. This may be due to different patients requiring different strategies of electrical stimulation in order to obtain a positive effect on tinnitus. It is, therefore, important to identify the most effective stimulation strategies to reduce tinnitus. The simplest possible strategy is stimulation by only one electrode. In this study, we investigated tinnitus suppression by electrical stimulation via a single electrode of the cochlear implant. METHODS: We performed a listening experiment in 19 adult participants, who had received a unilateral cochlear implant (CI) because of severe bilateral hearing loss. All of these patients had indicated that they suffered from tinnitus. During a 300-s interval, patients listened to blocks of single-electrode stimulation and rated the loudness of the stimulus and any effects on their tinnitus. The 300-s interval included a block of single-electrode stimulation (duration 120 s). In consecutive intervals, the stimulus differed in its cochlear location (basal or apical), its pulse rate (720 or 725 Hz, 1,200 Hz, and 2,400 or 2,320 Hz), and amplitude (just above threshold or equivalent to moderate loudness). Thus, 2 × 3 × 2 = 12 stimulus conditions were tested in each participant, and each condition was presented only once. During the experiment, the participants promptly rated the loudness of the stimuli and the loudness of their tinnitus on a Visual Analogue Scale (10-point VAS). RESULTS: Significantly more tinnitus reduction was observed with stimuli at a moderate intensity level (30%) compared to stimuli at near-threshold level (18%) (χ2 [1, N = 222] = 14.115, p < 0.01). No significant differences in tinnitus levels resulted from the different pulse rates and stimulation sites. Eight participants reported an increase of tinnitus loudness under at least one stimulus condition. Changes in tinnitus loudness were generally minor, and never exceeded 3 points on the VAS. The overall effect of cochlear implantation on tinnitus, that is, the effect with full-array stimulation, was not correlated with the effectiveness of the single-electrode stimulation on tinnitus. CONCLUSION: In conclusion, the effect of single-electrode stimulation on tinnitus is relatively insignificant in comparison to the effect of full-array stimulation. However, in some individual cases, sustained single-electrode stimulation may be beneficial for tinnitus management.

The Relation Between Tinnitus and a Neurovascular Conflict of the Cochleovestibular Nerve on Magnetic Resonance Imaging.

INTRODUCTION: Magnetic resonance (MR) imaging is often used in diagnostic evaluation of tinnitus patients. Incidental findings like a neurovascular conflict (NVC) in the cerebellopontine angle are often found; however, the diagnostic value of this finding remains unclear. The aim of this study is to investigate whether the type or degree of compression of the vestibulocochlear nerve is of diagnostic value in patients with a NVC. METHODS: A retrospective study was performed in 111 tinnitus patients with available MR imaging between 2013 and 2015. Clinical and audiometric variables were gathered and MR imaging was reevaluated by two neuroradiologists. NVCs were analyzed using a grading system based on previous research by Sirikci et al. RESULTS:: In total, 220 ears were available for assessment. In patients with unilateral tinnitus a loop compression and an indentation of the cochleovestibular nerve were more frequent than in patients with bilateral tinnitus. However, there was no significant difference in distribution of the type of compression between tinnitus and nontinnitus ears. Patient with unilateral tinnitus had a significantly higher degree of hearing loss in the symptomatic ear, compared with the asymptomatic ear and with the bilateral tinnitus group. Also, it was found that the degree of hearing loss did not differ between the various types of compression. CONCLUSION: This study did not find a diagnostic value of specific types of compression in patients with a NVC. Although the distribution of NVC classification was different in patients with unilateral and bilateral tinnitus, there was no definite relation between the type of NVC and the presence of ipsilateral tinnitus. Also, the degree of hearing loss was not related to specific types of NVC.

A Prospective Study of the Effect of Cochlear Implantation on Tinnitus.

Previous studies have shown diverse and sometimes even contrary results concerning the effect of cochlear implantation on tinnitus and the factors that can influence this effect. The aim of this prospective questionnaire study was to determine the effects of cochlear implantation on tinnitus and explore which factors can influence the effect of cochlear implantation on tinnitus. Forty-four of the patients implanted in our hospital returned 2 questionnaire packages, i.e., one before the cochlear implantation and one 6 months after implantation. Before implantation, 66% of the patients experienced tinnitus. This study shows that cochlear implantation could help to reduce tinnitus and the tinnitus handicap in at least 28% of the patients with preoperative tinnitus. In 72% of the patients the tinnitus remained after implantation. None of the patients developed tinnitus after implantation. A shorter duration of tinnitus prior to implantation, a more fluctuating type of tinnitus, a higher tinnitus handicap prior to implantation, and a round-window surgical approach might have a positive influence on the effect of cochlear implantation on tinnitus, but further research is necessary to confirm these findings.

Cluster Analysis to Identify Possible Subgroups in Tinnitus Patients.

INTRODUCTION: In tinnitus treatment, there is a tendency to shift from a "one size fits all" to a more individual, patient-tailored approach. Insight in the heterogeneity of the tinnitus spectrum might improve the management of tinnitus patients in terms of choice of treatment and identification of patients with severe mental distress. The goal of this study was to identify subgroups in a large group of tinnitus patients. METHODS: Data were collected from patients with severe tinnitus complaints visiting our tertiary referral tinnitus care group at the University Medical Center Groningen. Patient-reported and physician-reported variables were collected during their visit to our clinic. Cluster analyses were used to characterize subgroups. For the selection of the right variables to enter in the cluster analysis, two approaches were used: (1) variable reduction with principle component analysis and (2) variable selection based on expert opinion. RESULTS: Various variables of 1,783 tinnitus patients were included in the analyses. Cluster analysis (1) included 976 patients and resulted in a four-cluster solution. The effect of external influences was the most discriminative between the groups, or clusters, of patients. The "silhouette measure" of the cluster outcome was low (0.2), indicating a "no substantial" cluster structure. Cluster analysis (2) included 761 patients and resulted in a three-cluster solution, comparable to the first analysis. Again, a "no substantial" cluster structure was found (0.2). CONCLUSION: Two cluster analyses on a large database of tinnitus patients revealed that clusters of patients are mostly formed by a different response of external influences on their disease. However, both cluster outcomes based on this dataset showed a poor stability, suggesting that our tinnitus population comprises a continuum rather than a number of clearly defined subgroups.

Changes in tinnitus after cochlear implantation and its relation with psychological functioning.

This study retrospectively assessed the prevalence of tinnitus in cochlear implant patients and the changes after implantation in 212 patients implanted between 2000 and 2009. Patients were included at least 6 months after implantation and received 2 sets of questionnaires, one about the situation before implantation and one about the situation after implantation. Mostly standardized questionnaires assessed tinnitus handicap (Tinnitus Handicap Inventory, THI, and Tinnitus Handicap Questionnaire, THQ), tinnitus characteristics, hearing loss (Abbreviated Profile of Hearing Aid Benefit) and anxiety/depression (Hospital Anxiety and Depression Scale). Of the approached patients, 117 completed the full sets of questionnaires and 35 completed a short version. Preoperative tinnitus was reported by 51.3% of these patients, of which 55.6% reported a reduction or cessation of their tinnitus after implantation. However, 8.2% of the patients with tinnitus reported a postoperative deterioration of their tinnitus. In addition, among the patients without preoperative tinnitus, 19.6% reported the start of tinnitus after implantation. The self-reported change of tinnitus correlated with the pre- and postoperative scores on the THI and THQ. The THQ showed slightly more changes in scores after cochlear implantation compared to the THI. Overall hearing handicap and feelings of anxiety and depression decreased after implantation. In conclusion, tinnitus is reduced after cochlear implantation in an important part of the patients, but in a small part implantation has a negative effect on tinnitus. When tinnitus starts after implantation, the tinnitus handicap is mild.

A Bast-like valve in the pigeon?

The first description of the presence of a utriculo-endolymphatic valve in human fetuses was given by Bast in 1928. Since then this valve-like structure is called Bast's valve. Its exact function has not yet been established. The general opinion is that it has a protective function by having the possibility to separate the superior endolymphatic compartments of the labyrinth from the inferior compartment. Phylogenetically seen birds are the first vertebrates with a cochlear duct and a distinct inferior and superior part of the labyrinth. A structure in the pigeon inner ear, resembling Bast's valve in mammals, is described.

Fulminant post-tonsillectomy haemorrhage caused by aberrant course of the external carotid artery.

Haemorrhage, throat pain and otalgia are common complications following tonsillectomy. Haemorrhage is rarely life-threatening but in this paper we describe a fulminant secondary haemorrhage due to an aberrant external carotid artery in an eight-year-old boy. Acute surgical intervention with ligation of the external carotid artery was needed to control the bleeding.