Effects of transtemporal ultrasound application on brain temperature in an anthropomorphic skull model

Hintergrund: Die transtemporale Ultraschallthrombolyse ist ein vielversprechendes Verfahren, um die Standardtherapie des ischämischen Schlaganfalles zu verbessern. Einige Publikationen weisen jedoch darauf hin, dass dieses Verfahren potentielle Gefährdung von Gewebe, durch lokale Temperaturerhöhung mit sich bringt. Zielsetzung dieser Studie war es, den Effekt von im klinischen Alltag vewendeten transkraniellen Ultraschallgeräten die sowohl diagnostisch, als auch bereits in klinischen Pilotstudien zur therapeutischen Ultraschallthrombolyse eingesetzt werden und so wie von therapeutischen Geräten, in Hinsicht auf intrazerebrale Temperaturveränderungen und potentielle thermische Nebeneffekte evaluieren. Methoden: Anhand eines menschlichen Schädelmodells wurden die thermische Effekte (Haut, Schädel, Gehirn) von diagnostischem (1.8-MHz, maximum 0.72 W/cm, TIC 3.0, Duplex-mode) und therapeutischem (1-MHz or 3-MHz, 1 W/cm, continuous or pulsed mode) Ultraschall evaluiert. Die Temperatursensoren befanden sich entlang des Schallstrahles der auf das Zielgebiet der Arteria Cerebri Media ausgerichtet war. Die Ultraschallapplikation dauerte rund 120 Minuten. Ergebnisse: Unter Beschallung mit diagnostischem Ultraschall stieg die Temperatur um 0.9C (Gehirn), 1.6C (Knochen) und um 4.8C (Haut) an. Unter Verwendung von therapeutischem Ultraschall (1-MHz) waren die entsprechenden Werte 1.2C, 2.1C und 4.2C (gepulst 1:20) beziehungsweise 2.3C, 4.5C und 9.0C (gepulst 1:5). Bei Verwendung von therapeutischem Ultraschall (3-MHz) stieg die Temperatur jeweils um 1.4C, 2.8C und 5.8C (gepulst 1:20) beziehungsweise um 3.1C, 5.8C und 12.2C (gepulst 1:5). Kontinuierliche Beschallung (1-MHz und 3-MHz) führte zu einem Temperaturanstieg um 1.7C, 3.6C und 13.9C beziehungsweise um 1.4C, 4.3C und 17.1C. Conclusion: Die Behandlung mit diagnostischem Ultraschall unter Verwendung der höchsten Leistungseinstellungen führt nur zu geringen Temperaturerhöhungen im Bereich des beschallten Gewebes und kann somit als sicher betrachtet werden. Demgegenüber erzeugt therapeutischer Ultraschall (1-MHz, 3-MHz) selbst im gepulsten Modus potentiell schädigende Erwärmung im Gewebe.Background and Purpose: Transtemporal sonothrombolysis is a promising tool for a more effective treatment in acute stroke patients. However, some reports revealed serious side effects, which might be potentially connected to local temperature elevation. To gain better insight into cerebral temperature changes and possible side effects during transtemporal sonication, diagnostic and therapeutic ultrasound applications were evaluated using an anthropomorphic skull model. Methods: The impact of diagnostic (1.8-MHz, maximum 0.72 W/cm, TIC 3.0, Duplex-mode) and therapeutic (1-MHz or 3-MHz, 1 W/cm, continuous or pulsed mode) ultrasound application on temperature changes (skin, temporal bone, brain) was evaluated using a human skull. Temperature sensors were located along the ultrasound beam to the middle cerebral artery. Sonication lasted 120 minutes. Results: Diagnostic ultrasound showed a maximum temperature increase of 0.9/1.6/4.8C (brain/temporal bone/skin) after 120 minutes. Therapeutic-1-MHz ultrasound raised temperature by 1.2/2.1/4.2C (pulsed 1:20) and by 2.3/4.5/9.0C (pulsed 1:5) after 120 minutes. Therapeutic-3-MHz ultrasound raised temperature by 1.4/2.8/5.8C (pulsed 1:20) and by 3.1/5.8/12.2C (pulsed 1:5) after 120 minutes, respectively. Continuous application of therapeutic ultrasound (1-MHz and 3-MHz) led to a temperature increase of 1.7/3.6/13.9C and 1.4/4.3/17.1C after 3 minutes. Conclusions: Diagnostic ultrasound at maximum energy output showed only a moderate temperature increase and can be considered as safe. Therapeutic sonication with 1-MHz and 3-MHz transducers are very powerful in delivering energy so that even pulsed application modes resulted in significant and potentially harmful temperature increases.submitted by Erich VyskocilAbweichender Titel laut Übersetzung der Verfasserin/des VerfassersZsfassung in dt. SpracheWien, Med. Univ., Diss., 2010OeBB(VLID)171626

The Functional Hearing Gain with an Active Transcutaneous Bone Conduction Implant Does Not Correlate with the Subjective Hearing Performance

The functional hearing outcome with hearing implants does not always properly reflect the subjective benefit in everyday listening situations. In this study, the functional hearing gain and the impact on the subjective hearing ability and quality of life were assessed in patients with a Bonebridge. A chart review was performed on 45 patients with a Bonebridge who were provided with questionnaires regarding the hearing quality and health-related quality of life during their last clinical visit. The questionnaires consisted of the Speech, Spatial and Qualities (SSQ) and the Health Utility Index Mark 3 (HUI3). Eleven patients had to be excluded due to missing data. A total of 34 patients (37 ears) were included in the study. Aided hearing thresholds were significantly lower compared with the unaided condition, with a mean functional gain of 26.87 dB for patients with mixed/conductive hearing loss (MHL/CHL). Although patients with single-sided deafness (SSD) scored slightly lower on the SSQ compared with patients with MHL/CHL, all included patients reported improved subjective hearing quality with the BB compared with the hearing situation before implantation. No correlation was found between the functional hearing gain and the subdomains of the SSQ. SSD patients scored the HUI3 subdomain “hearing” slightly lower compared with MHL/CHL patients. Although not significant, a relationship was found between the functional gain and the “hearing” subdomain. No correlation was found for the other subdomains of the HUI3. Audiological measurements showed significantly improved hearing thresholds with the Bonebridge. Most importantly, the subjective benefit achieved in everyday listening situations was superior compared with the previous hearing condition. The lack of correlation between subjective questionnaire results and the functional hearing gain shows the importance of assessing both audiological and subjective hearing quality parameters in clinical routine

Fixed and adaptive beamforming improves speech perception in noise in cochlear implant recipients equipped with the MED-EL SONNET audio processor

Objective: To determine the impact of the fixed and adaptive beamforming technology of the new MED-EL SONNET cochlear implant audio processor on speech perception in noise. Methods: The study cohort comprises 18 postlingually deafened adult cochlear implant recipients with at least six months of experience. Speech reception thresholds were measured with the Oldenburg Sentence Test in continuous, speech-shaped noise. Target sentences were presented in front of the listener, with noise sources placed at -135° and 135°, respectively. Outcome measures were the differences in speech reception threshold using omnidirectional, fixed and adaptive beamformer microphone settings. Results: The use of directional microphones significantly improved speech reception thresholds: fixed beamformer vs. omnidirectional: 4.3 dB (95%-CI [3.15.5]), p<0.0001adaptive beamformer vs. omnidirectional: 6.1 dB (95%-CI [4.97.3]), p<0.0001and adaptive beamformer vs. fixed beamformer: 1.8 dB (95%-CI [0.73.0]), p = 0.001. Conclusion: This study confirms the previously reported improvements in speech perception in noise of the fixed beamformer microphone setting and is the first to report significant improvements in speech perception in noise when applying the adaptive beamformer microphone settings of the SONNET audio processor. Cochlear implant users may be able to benefit from improved hearing performance especially in difficult listening situations

Medical, Technical and Audiological Outcomes of Hearing Rehabilitation with the Bonebridge Transcutaneous Bone-Conduction Implant: A Single-Center Experience

Bone-conduction implants are a standard therapeutic option for patients with conductive, unilateral, or mixed hearing loss who either do not tolerate conventional hearing aids or can benefit from surgery. The aim of this study was to evaluate long-term medical and technical outcomes, and audiological results with the Bonebridge transcutaneous bone-conduction implant. This retrospective study included all patients implanted with a bone-conduction hearing implant at a tertiary medical referral center between March 2012 and October 2018. Medical and technical outcomes included the mean length of implant usage, medical and technical complications (skin and wound infection, lack of benefit, technical failure), explantations and revisions, coupling approaches, implant failure rate, implant survival and the implant loss for added follow-up years. Auditory results were measured by functional hearing gain and the Freiburger monosyllabic test at 65 dB sound pressure level. Sixty-four patients were included in the study; five of these were implanted bilaterally (69 devices). Five unilaterally implanted patients were lost to follow-up. The mean follow-up was 27.1 months (range: 0.2 months&ndash;6.3 years). The mean implant usage was 25.9 months (range: 0.2 months&ndash;6.3 years). Fifty-seven implants (89.1%) were in use at the end of the follow-up period. Complications occurred in six ears (9.4%). Five implants (7.8%) were explanted without reimplantation. Device failure occurred in one implant (1.6%), which was possibly caused by recurrent head trauma. The rate of implant loss due to technical device failure (damage to device) was 1 per 72 follow-up years. The mean improvement on the Freiburger monosyllabic test (52.1%, p = 0.0001), and in functional hearing gain across frequencies (26.5 dB, p = 0.0001) was significant. This single-center follow-up reveals the medical and technical reliability of a transcutaneous bone-conduction implant for hearing rehabilitation because complication and revision rates were low. The majority of patients still used the device at the end of the observation period. Implantation resulted in favorable hearing outcomes in comparison to that of unaided conditions. Cautious patient selection mainly regarding co-morbidities, the history of chronic otologic diseases and proper surgical technique seems to be crucial in reducing complications

Fixed and adaptive beamforming improves speech perception in noise in cochlear implant recipients equipped with the MED-EL SONNET audio processor

Objective To determine the impact of the fixed and adaptive beamforming technology of the new MED-EL SONNET cochlear implant audio processor on speech perception in noise. Methods The study cohort comprises 18 postlingually deafened adult cochlear implant recipients with at least six months of experience. Speech reception thresholds were measured with the Oldenburg Sentence Test in continuous, speech-shaped noise. Target sentences were presented in front of the listener, with noise sources placed at -135 and 135, respectively. Outcome measures were the differences in speech reception threshold using omnidirectional, fixed and adaptive beamformer microphone settings. Results The use of directional microphones significantly improved speech reception thresholds: fixed beamformer vs. omnidirectional: 4.3 dB (95%-CI [3.1; 5.5]), p<0.0001; adaptive beamformer vs. omnidirectional: 6.1 dB (95%-CI [4.9; 7.3]), p<0.0001; and adaptive beamformer vs. fixed beamformer: 1.8 dB (95%-CI [0.7; 3.0]), p = 0.001. Conclusion This study confirms the previously reported improvements in speech perception in noise of the fixed beamformer microphone setting and is the first to report significant improvements in speech perception in noise when applying the adaptive beamformer microphone settings of the SONNET audio processor. Cochlear implant users may be able to benefit from improved hearing performance especially in difficult listening situations.(VLID)479101

Direct comparison of mastoidal and retrosigmoidal placement of a transcutaneous bone conduction device after canal wall down tympanoplasty

(VLID)342388

Progressive Sensorineural Hearing Loss in Vibrant Soundbridge Users Requiring Cochlear Implantation

Less than 20% of patients with sensorineural hearing loss (HL) provided with the Vibrant Soundbridge (VSB) experience a progressive HL and warrant cochlear implantation (CI). The aim of this study was to identify possible predictors of progressive HL prior to VSB implantation. This retrospective study included all consecutive ears with sensorineural HL provided with the VSB between 1998 and 2016. The patient cohort was divided in a study group comprising patients who underwent CI (CI group) after years of VSB usage and those who did not require VSB replacement during the observational time (control group). Pre- and postoperative pure-tone audiometry thresholds were compared among the two groups. Fifteen out of 81 VSB devices (18.5%) required a CI. The CI group had higher preoperative air-conduction (AC) thresholds than the control group (64.3 ± 8.9 dB vs. 56.3 ± 12.9 dB; p = 0.007) at the time of the VSB implantation. On average, the CI group was significantly younger (39.1 ± 12.3 years vs. 52.6 ± 16.2 years; p = 0.003). In conclusion, VSB users with higher preoperative AC thresholds and younger age at the time of VSB implantation might be at risk for progressive HL within the upcoming eight years and need a further CI surgery. Preoperative counseling is particularly advisable in this patient group

Outcome in Patients with Partial and Full-Thickness Cheek Defects following Free Flap Reconstruction—A Multicentric Analysis of 47 Cases

The objective of this study was to evaluate whether the extent of tumor resection and free flap reconstruction influences functional outcome and complications in patients with solid malignancies of the cheek. Therefore, we retrospectively assessed recipient site complications and functional outcomes in 47 patients with solid malignancies of the cheek who underwent either partial (n = 30; 63.8%) or full-thickness (n = 17; 36.2%) cheek resection with free flap reconstruction. Complications occurred in 12 (70.6%) patients after full thickness resections with creation of through-and-through defects compared to 14 (70.6%) patients with partial defects (p = 0.138). Among those 26 patients (55.3%), major recipient site complications, like development of salivary fistula or free flap loss, were observed in 10 (21.3%) and 2 (4.3%) cases, respectively, while minor complications, like wound dehiscence and local infections, were found in 14 (29.8%) and 9 (19.1%) patients. Complications were noticed particularly after reconstruction of suborbital defects (69.2%; p = 0.268), of which occurrence of salivary fistulae was the most common (46.2%; p = 0.035). Similarly, functional outcomes including oral incompetence, ectropion, and trismus were not affected by the extent of resection (p = 0.766). However, oral incompetence was higher in patients with tumors originating from the oral cavity (p = 0.020) and after the performance of mandibulectomy (p = 0.003). Overall, there was no difference in functional outcome or recipient site morbidity between tumor resections resulting in full-thickness and partial defects

The Laryngoscope / Long-term outcome of hearing rehabilitation with an active middle ear implant

Objective To assess the audiological and longterm medical and technical followup outcomes of an active middle ear implant. Methods This was a retrospective medical chart analysis of all patients provided with an active middle ear implant in a tertiary academic medical referral center between September 1, 1998, and July 31, 2015. Main outcome measures were medical and technical complications, revisions, reimplantations, explantations, coupling approaches, mean time of use, pre and postoperative hearing thresholds, functional hearing gain across frequencies (2504,000 Hz), and Freiburg monosyllablic word test at 65 dB. Results One hundred and three patients were identified. Fifteen were implanted bilaterally (n = 118 Vibrant Soundbridge devices [MEDEL, Innsbruck, Austria]). Seventyseven devices were implanted for sensorineural and 41 for mixed and conductive hearing loss. Patients used the implant for 6.7 years (range 0.7 months17.9 years) on average. Ninetyone patients (77.12%) were using the device at the end of the observation period. An overall complication rate of 16.1% was observed. The revision and explantation rates were higher for devices implanted between 2004 and 2006. The device failure rate was 3.4%. Audiological evaluation showed significant hearing gains for both hearing loss patient groups. Conclusion This longterm followup reveals the reliability of the active middle ear implant in a single center. Overall complication rate and device failure rate are acceptable. The complication rate was higher during implementation of alternative coupling approaches. The audiological benefit was satisfactory in patients with all hearing loss types. The majority of implanted patients used the implant at the end of the observation period.(VLID)341189

An In Vitro Study Evaluating the Safety of Mesalazine on Human Nasoepithelial Cells

Chronic rhinosinusitis (CRS) is a disease characterised by the inflammation of the nasal and paranasal cavities. It is a widespread condition with considerable morbidity for patients. Current treatment for chronic rhinosinusitis consists of appropriate medical therapy followed by surgery in medically resistant patients. Although oral steroids are effective, they are associated with significant morbidity, and disease recurrence is common when discontinued. The development of additional steroid sparing therapies is therefore needed. Mesalazine is a commonly used therapeutic in inflammatory bowel disease, which shares a similar disease profile with chronic rhinosinusitis. This exploratory in vitro study aims to investigate whether mesalazine could be repurposed to a nasal wash, which is safe on human nasoepithelial cells, and retains its anti-inflammatory effects. CRS patients’ human nasal epithelial cells (HNECs) were collected. HNECs were grown at an air-liquid interface (ALIs) and in a monolayer and challenged with mesalazine or a non-medicated control. Transepithelial electrical resistance, paracellular permeability, and toxicity were measured to assess epithelial integrity and safety. The anti-inflammatory effects of mesalazine on the release of interleukin (IL)-6 and tumour necrosis factor alpha (TNF-α) were analysed using human leukemia monocytic cell line (THP-1). mesalazine did not impact the barrier function of HNEC-ALIs and was not toxic when applied to HNECs or THP-1 cells at concentrations up to 20 mM. mesalazine at 0.5 and 1 mM concentrations significantly inhibited TNF-α release by THP-1 cells. mesalazine effectively decreases TNF-α secretion from THP-1 cells, indicating the possibility of its anti-inflammatory properties. The safety profile of mesalazine at doses up to 20 mM suggests that it is safe when applied topically on HNECs