[Standardized risk-based antibiotic prophylaxis and adhesive film dressing for the prevention of wound infection following cochlear implantation]. / Standardisierte risikobasierte Antibiotikaprophylaxe und adhäsiver Filmverband zur Prävention von Wundinfektion bei Cochleaimplantation.

BACKGROUND: There is no consensus in the pertinent literature regarding the optimal antibiotic prophylaxis (AP) for cochlear implantation (CI). This study evaluates the implementation of standardized risk-based AP combined with application of an adhesive film dressing. MATERIALS AND METHODS: All CI cases since September 2019 were retrospectively reviewed for postoperative wound complications. While all patients received preoperative AP with ceftriaxone, postoperative AP after CI in patients older than 7 years was no longer routinely performed in our clinic. Exceptions were made according to predefined criteria for an increased risk of infection. The wound was covered with a transparent adhesive polyurethane film. RESULTS: In 72% of the 219 cases, we did not perform postoperative AP. The overall wound complication rate was 2.7% (in the groups with and without postoperative AP, 4.9% and 1.9%, respectively). Wound infection did not occur in any of the patients without postoperative AP older than 70 years (n = 32), with controlled diabetes mellitus (n = 19), or with reimplantation due to technical defect (n = 19). The film did not need to be changed until the suture material was removed. CONCLUSION: Standardized risk-based AP can avoid prolonged administration of antibiotics in selected patients. The film dressing permits continual examination and sufficient wound protection.

Novel noncanonical splice site variant causes mild CHD7-related disorder with variable intrafamilial expressivity.

The clinical diagnosis criteria for CHARGE syndrome have been revised several times in the last 25 years. Variable expressivity and reduced penetrance are known, particularly in mild and familial cases. Therefore, it has been proposed to include the detection of a pathogenic CHD7 variant as a major diagnostic criterion. However, intronic variants not located at the canonical splice site are still underrepresented in mutation databases, often because functional analysis is not performed in the diagnostic setting. Here, we report a two-generation family that did not meet the criteria for CHARGE syndrome, until the molecular findings were taken into account. By exome sequencing, we detected an intronic variant in a male individual, who presented with unilateral external ear malformation, bilateral semicircular canal aplasia, polydactyly, vertebral body fusion and a heart defect. The variant was inherited by his mother, who also had bilateral semicircular canal aplasia additionally to unilateral sensorineural hearing impairment, unilateral mandibular palpebral synkinesia, orofacial cleft, and dysphagia. Using RNA studies, we were able to demonstrate that aberrant splicing occurs at an upstream cryptic splice acceptor site, resulting in a frameshift and premature stop of translation. Our data show causality of the noncanonical intronic CHD7 variant and end the diagnostic odyssey of this unsolved phenotype of the family.

Piezoelectric ear surgery: a systematic review.

BACKGROUND: The piezoelectric instrument (PEI) offers a novel technique for bone removal in ear surgery with a combination of micro-oscillation and cavitation. The aim of this review is to explore the advantages, disadvantages, and limitations of this instrument in comparison to the drill. MATERIALS AND METHODS: We conducted a search of PubMed/MEDLINE and Google Scholar in accordance with the PRISMA recommendations. The primary selection included all studies reporting on the use of PEI in ear surgery or its effect on the inner ear. Only studies with a control group were included in the secondary selection. RESULTS: The first search identified 49 studies between 2003 and 2022. These reported on a total of 1162 ear operations, during which PEI was used for various indications. Most data were based on uncontrolled retrospective studies or case reports (76%). Only one of the five controlled clinical studies was prospective and randomized. The advantages of PEI weighed against its limitations and disadvantages were critically analyzed in comparison to the drill. CONCLUSION: Piezoelectric surgery is an innovative and promising surgical technique in the temporal bone. PEI appears to enable safer and more precise bone removal in close proximity to soft tissue when compared to the drill. The slower bone removal and cost factors represent current limitations to its wider use in ear surgery.

[Piezoelectric ear surgery: a systematic review. German version]. / Piezoelektrische Ohrchirurgie: systematische Literaturübersicht.

BACKGROUND: The piezoelectric instrument (PEI) offers a novel technique for bone removal in ear surgery with a combination of micro-oscillation and cavitation. The aim of this review is to explore the advantages, disadvantages, and limitations of this instrument in comparison to the drill. MATERIALS AND METHODS: We conducted a search of PubMed/MEDLINE and Google Scholar in accordance with the PRISMA recommendations. The primary selection included all studies reporting on the use of PEI in ear surgery or its effect on the inner ear. Only studies with a control group were included in the secondary selection. RESULTS: The first search identified 49 studies between 2003 and 2022. These reported on a total of 1162 ear operations, during which PEI was used for various indications. Most data were based on uncontrolled retrospective studies or case reports (76%). Only one of the five controlled clinical studies was prospective and randomized. The advantages of PEI weighed against its limitations and disadvantages were critically analyzed in comparison to the drill. CONCLUSION: Piezoelectric surgery is an innovative and promising surgical technique in the temporal bone. PEI appears to enable safer and more precise bone removal in close proximity to soft tissue when compared to the drill. The slower bone removal and cost factors represent current limitations to its wider use in ear surgery.

Multi-mode grounding and monophasic passive discharge stimulation avoid aberrant facial nerve stimulation following cochlear implantation.

We report on a case with severe facial nerve stimulation via a cochlea-facial nerve dehiscence that was most likely the result of prolonged occlusive hydrocephalus. The successful treatment of this adverse effect demonstrates for the first time its complete resolution using a multi-mode grounding and monophasic passive discharge stimulation.

Cochlear reimplantation from mid-scala to lateral wall electrode array: Surgical and hearing outcome.

A mid-scala cochlear implant electrode array, which was inserted with an atraumatic round window approach, could be replaced with longer lateral wall electrode array. Deeper electrode insertion seems to have beneficial influence on the hearing quality.

Piezoelectric canalplasty for exostoses and osteoma.

OBJECTIVE: To evaluate the safety profile and surgical technique for removal of symptomatic exostoses and osteoma of the external auditory canal with a micro-oscillating piezoelectric device. METHOD: A chart review was conducted on patients undergoing piezoelectric canalplasty between 2019 and 2021 at tertiary referral hospital. Surgery was performed by two surgeons with varying experience. Bone removal was achieved using both osteotomy and osteoplasty. Postoperative complications, operative time and hearing outcome were evaluated. RESULTS: The study comprised 16 patients (16 ears). No major complications occurred. The skin of the auditory canal was completely preserved in all patients without injury to the tympanic membrane. Except for one patient with known noise-induced hearing loss, there was no postoperative deterioration of the bone-conduction threshold more than 10 dB HL at any frequency. The difference of the bone-conduction threshold in pure-tone audiometry (average for 0.5, 1, 2 and 4 kHz) three weeks postoperatively had a median of 0.6 dB ± 5.7. One patient complained of temporary new tinnitus. One patient had prolonged wound healing. Mean operative time was comparable with literature data. CONCLUSION: The atraumatic characteristics of the piezoelectric instrument enable low-risk removal of external auditory canal exostoses and osteoma. Through the combination of precise osteotomy and osteoplasty, this novel instrument has the potential to become established in routine canalplasty.

Piezosurgery in Translabyrinthine-Approach Exposure of the Internal Auditory Canal.

OBJECTIVE: To assess the applicability of the piezoelectric device in translabyrinthine-approach exposure of the internal auditory canal. METHODS: In three cases with vestibular schwannoma, the bone around the internal auditory canal was completely removed by means of piezosurgery. Evaluation was performed by an experienced surgeon, and a second relatively inexperienced surgeon. RESULTS: Irrespective of surgical experience, piezosurgery proved to be a safe method for exposure of the internal auditory canal. Compared with the conventional procedure it provides an improved surgical view and more precise bone removal in a narrow operating field. This novel technique has the characteristics to reduce the corresponding risk of accidental slipping with consequent thermal and mechanical injury to the dura and neurovascular structures. The major disadvantage of piezosurgery is the longer time required for bone removal. CONCLUSION: The micro-oscillating piezoelectric device is a useful adjunct to the rotating burr during removal of the bone around the internal auditory canal in translabyrinthine approach. It could reduce the risk of injury to neurovascular structures at the bone-to-soft tissue interface.

[Late complications after tracheotomy in the nursing home]. / Spätkomplikationen nach Tracheotomie im ambulanten Pflegebereich.

BACKGROUND: Advances in modern intensive care have led to a sharp increase in the number of tracheotomies performed in intensive care units. In contrast to surgical epithelial tracheostomy (ST), a less sturdy stoma is created by means of percutaneous dilation of tracheotomy (PDT). The advantages of a PDT compared to ST are the simpler logistical efforts, associated cost reduction and minimally invasive nature of the process. However, due to variability in airway management, late complications can cause problems, especially in nursing homes. MATERIAL AND METHODS: Nursing facilities were given a standardized questionnaire which included information about patient type, tracheotomy type, cannula management protocol, TK management protocol, type of complications occuring at the tracheostoma as well as frequency. RESULTS: Nearly 66 % of the patients were treated with PDT. The complication rates of PDT patients were statistically and significantly higher for all observed complication types compared to the group of patients receiving ST care. 80 % of patients treated with PDT required readmission to clinic for tracheostoma revision, versus 23 % in the ST-patients. DISCUSSION: A PDT places special demands on the nursing staff in postoperative aftercare. The decision as to which form of tracheotomy is best suited to a particular patient should be made with a multidisciplinary team and depending on the indication. Given the probable long-term nature of the tracheotomy, a surgical tracheostomy should be the therapy of first choice.

Influence of Floating-Mass Transducer Coupling Efficiency for Active Middle-Ear Implants on Speech Recognition.

OBJECTIVE: The efficiency of vibroplasty (coupler-floating mass transducer [FMT] assembly) can be monitored by direct stimulation of the inner ear through the active middle-ear implant system and comparison of the vibroplasty in vivo threshold and the postoperative bone-conduction pure-tone threshold. The aim of this study was to compare the vibroplasty in vivo threshold with the postoperative speech recognition in patients with a high preoperative maximum word recognition score. STUDY DESIGN: Retrospective cohort study of German-speaking patients implanted with a vibrating ossicular prosthesis (VORP) 502 or VORP 503 and high preoperative maximum word recognition score between the years of 2011 and 2015. SETTING: Multicenter study of four German centers. PATIENTS: Twenty-three active middle-ear implant users. INTERVENTION: Rehabilitative. MAIN OUTCOME MEASURES: Bone-conduction pure-tone and vibroplasty thresholds, postoperative aided word recognition score (WRS) at 65 dB SPL (sound pressure level) and preoperative maximum WRS with Freiburg monosyllabic words. RESULTS: The mean postoperative aided WRS at 65 dB SPL was 82%. An increasing difference between vibroplasty thresholds and bone-conduction thresholds was associated with a higher discrepancy between the unaided maximum WRS and the postoperative aided WRS. Only if this difference was less than 20 dB, an articulation index of 0.5 (WRS = 75%) or more was achieved. CONCLUSIONS: Audiological outcome after vibroplasty depends on the coupling efficiency reflected by the vibroplasty threshold.

Horizontal VOR function shows frequency dynamics in vestibular schwannoma.

The objective of this retrospective study was to investigate the horizontal vestibulo-ocular reflex (hVOR) pathway with caloric test (low-frequency hVOR) and video head impulse test (vHIT) (high-frequency hVOR) in patients with sporadic vestibular schwannoma (69 patients, 27-86 years, mean age 58.1 years) and to compare both test methods in terms of their sensitivity and specificity to detect a retrocochlear lesion. Test results with a unilateral weakness (UWCaloric) >25 % (caloric test) or a Mean-GainvHIT <0.79/asymmetry ratio of Gain (AR-GainvHIT) >8.5 % and accompanied refixation saccades (vHIT) were considered abnormal. The overall sensitivity of the caloric test was 72 %. The evaluation of AR-GainvHIT detected more abnormal cases than did Mean-GainvHIT (44 vs. 36 %). In up to 4 %, a normal caloric test result was related to an abnormal vHIT. There was only a moderate correlation of UWCaloric and AR-GainvHIT (r = 0.54, p < 0.05) with a linear regression line intercept/slope of 32.2/0.9 (p < 0.05). Receiver operating characteristics curve analysis exhibited at a UWCaloric of 50 % a vHIT sensitivity/specificity/positive predictive value/negative predictive value of 0.45/0.9/0.94/0.42. Vestibular testing at varying frequencies provides deeper insights into hVOR function and is helpful in detecting a cerebello-pontine lesion. Whereas caloric test yields a high sensitivity for nerve dysfunction, vHIT test reveals a remaining function of hVOR in the high-frequency range.

Caloric stimulation and video-head impulse testing in Ménière's disease and vestibular migraine.

CONCLUSION: Both the bithermal caloric test and the video-head impulse test (vHIT) were more often abnormal in Ménière's disease (MD) than in vestibular migraine (VM). Horizontal vestibulo-ocular reflex (hVOR) evaluation with caloric test (low-frequency test) was significantly more often abnormal than vHIT (high-frequency test). Therefore, both tests can be used in a complementary way for frequency-selective testing of peripheral vestibular function. OBJECTIVES: To compare the results of caloric testing and vHIT in MD and VM and to determine which test is more sensitive to uncover peripheral vestibular hypofunction. METHODS: Patients with MD (n=30) or VM (n=23) were examined with the caloric test and vHIT. The parameters analyzed were the canal paresis factor for the caloric test and the hVOR gain on both sides in vHIT. RESULTS: The caloric test was abnormal in 67% of patients with MD and in 22% with VM (p=0.002), while the vHIT showed an hVOR deficit in 37% in MD and 9% in VM (p=0.025). In all, 28% of patients with an abnormal caloric test had a normal vHIT, whereas 6% of those with an abnormal vHIT had a normal caloric test. The sensitivity of vHIT compared with caloric testing was 55% for MD and 40% for VM. Neither the caloric test nor vHIT could detect significant differences between early (<5 years) or advanced stages (>5 years) of MD or VM.

The inner structure of human otoconia.

BACKGROUND: The architecture of human otoconia has been only poorly understood up to now. Currently, it is assumed that otoconia contain a central core surrounded by a shell. OBJECTIVES: To investigate the inner structure of human otoconia. METHODS: Human otoconia were investigated by environmental scanning electron microscopy (ESEM). The diffraction behavior was analyzed using X-ray techniques (XRD). Focused ion beam (FIB) slices of otoconia were investigated by transmission electron microscopy (TEM). The results were correlated with observations on degenerate human otoconia and decalcification experiments using ethylenediaminetetraacetic acid (EDTA). Artificial otoconia (calcite-gelatine and calcite-gelatine/agarose composites) were investigated in the same way and compared with human otoconia. RESULTS: Human otoconia represent highly mosaic-controlled calcite-based nanocomposites. The inner structure is composed of 3 + 3 branches with an ordered arrangement of nanocomposite particles and parallel orientation of fibrils. The surrounding belly is less ordered and appears more porous. Degenerate otoconia show a successive dissolution of the belly region exposing to the inner structure (branches) in later stages of degeneration. Artificial otoconia reveal identical chemical, crystallographic and morphologic patterns. They are, however, larger in size. CONCLUSION: Human otoconia show an inner architecture consisting of a less dense belly region and 3 + 3 more dense branches meeting at a central point (center of symmetry). The differences in volume densities and the resulting solubility may play a role in BPPV. Artificial otoconia may serve as a model for further investigations.

Detection of human utricular otoconia degeneration in vital specimen and implications for benign paroxysmal positional vertigo.

Otoconia are assumed to be involved in inner ear disorders such as benign paroxysmal positional vertigo (BPPV). Up to now, the distinct structure and morphology of intact and degenerate human utricular otoconia has been only poorly investigated on vital specimen. In this study, human otoconia were obtained from the utricle in five patients undergoing translabyrinthine vestibular schwannoma surgery. Specimens were examined by environmental scanning electron microscopy. Intact and degenerate otoconia as well as fracture particles of otoconia and bone were analyzed by energy dispersive X-ray microanalysis (EDX) and powder X-ray diffraction (XRD). Intact otoconia reveal a uniform size showing characteristic symmetry properties. Degenerative changes can be observed at several stages with gradual minor and major changes in their morphology including fragment formation. EDX analyses reveal the characteristic chemical composition also for otoconia remnants. XRD shows that intact and degenerate otoconia as well as remnants consist of the calcite modification. In conclusion, electron microscopy serves as a standard method for morphological investigations of otoconia. Human utricular otoconia show a uniform outer morphology corresponding to a calcite-based nanocomposite. Morphological changes provide further evidence for degeneration of utricular otoconia in humans, which might be a preconditioning factor causing BPPV. In case of uncertain origin, particles can be clearly assigned to otoconial origin using EDX and XRD analyses.

Retrospective analysis of titanium plate-retained prostheses placed after total rhinectomy.

PURPOSE: To report the use of a new platelike system (Titanium Epiplating System, Medicon, Tuttlingen, Germany) for rehabilitation of patients after total rhinectomy. MATERIALS AND METHODS: This retrospective study was conducted on all patients treated between August 2001 and July 2006 with total or subtotal rhinectomy. The clinical outcomes and satisfaction of patients receiving nasal prostheses were evaluated, and the success rate of the subperiosteal implants was determined. Quality of life (QOL) was evaluated with a standardized questionnaire. Patients who had experience with different retention methods responded to a five-point scale evaluating their current satisfaction. RESULTS: Eleven patients (four women and seven men) received nasal prostheses. The mean age was 63 +/- 12 years (range, 43 to 84 years). Nine patients were fitted with subperiosteal microplates and followed for a mean of 35 months. Two patients had subtotal rhinectomy and did not receive implants. In four patients immediate implant placement (concurrent with tumor resection) was performed; the other five patients received implants later. The implant success rate was 82%. There was no early implant loss, although one patient lost his implants after 3 years and another patient lost one implant after 1.5 years. QOL scores demonstrated high acceptance of implant fixed retention in comparison with other retention methods (P = .001). CONCLUSIONS: Implantation of anatomically prefabricated titanium plates has a high success rate in the nasal area, although late implant loss may occur. Patient perceptions of QOL show improvement when prostheses are retained by subperiosteal implants.

Comparing the habituation of late auditory evoked potentials to loud and soft sound.

The objective fitting of hearing aids and cochlear implants remains a challenge. In particular, the determination of whether sound is perceived as too loud or comfortable represents an unsolved problem in noncooperative patients. In a first step of an ongoing study, we assess the feasibility of habituation correlates in late auditory evoked potentials (LAEPs) to discriminate between a soft sound (SS) of 50 dB SPL and a loud sound (LS) of 100 dB SPL. We applied a new sweep-to-sweep time-scale coherence measure to analyse the habituation in LAEPs, i.e., relative changes within sweep sequences. From the comparison between both stimulation levels, a total discrimination of responses to SS and LS in the individual normal hearing subject was possible. As just relative changes in SS and LS sweep sequences were considered, purely exogenously driven morphological alternations in the responses such as intensity related amplitude and latency changes were excluded from the analysis. It is concluded that the proposed method allows for the reliable detection of auditory habituation and differentiation of SS from LS. The proposed scheme might provide an electrophysiological measurement and signal processing framework for the objective detection of the most comfortable loudness level and can be used in further, more clinically oriented studies.

Tumor risk assessment by means of immunocytochemical detection of early pre-malignant changes in buccal smears.

Increasing incidence of carcinomas in the upper aero-digestive tract, both in Germany and in other European countries requires development of new preventive strategies. The cure rate at advanced tumor stages remains poor in spite of a variety of available therapeutic methods. In the present study the quantitative assessment of a pre-malignant mucosa lesion within a field cancerization was performed by means of immunocytochemical methods. This may allow individuals with an increased risk of developing malignant disease to be identified. Cytosmears taken from healthy buccal mucosa of tumor patients (n=50) and from healthy probands (n=100) with different tobacco and alcohol consumption levels were examined with regard to identifying increased expression of the proliferation markers (PCNA, MIB1), of the tumor suppressor gene product p53 as well as the oncogene product cyclin D1. There was a significant difference in expression of investigated proliferation markers between tumor patients and healthy probands (p<0.0001). When comparing the rate of positively marked cell nuclei to cigarette pack years the marker cyclin D1 and MIB1 show an increased rate in the groups with high tobacco consumption as compared to the group with a low exposure (p>0.05). It could be possible to use the marker MIB1 and cyclin D1 to screen risk groups, since the relative morbidity risk (odds ratio) increases (by 45-62 times) if the threshold value of 4 positively marked cell nuclei is exceeded.

VCAM-1 increases levels of HGF in eosinophilic chronic rhinosinusitis cell culture.

BACKGROUND: Eosinophilic chronic rhinosinusitis (ECRS) is one of the most common diseases worldwide. To date the underlying cause remains unclear and no drug has been accredited for first-line therapy. VCAM-1 has been reported to play a pivotal role in establishing ECRS. Other authors have reported that inflammatory cytokines may mediate changes in the underlying epithelium in the sinuses through hepatocyte growth factor HGF. In our study, the effect of VCAM-1 on HGF levels was investigated. MATERIALS AND METHODS: ECRS cell cultures were incubated with VCAM-1 and HGF levels were determined after 16, 24, 48 and 72 hours. RT-PCR was enrolled to depict the HGF-RNA levels. RESULTS: Sixteen hours of incubation showed 28.5 pg/ml HGF, whereas in the control 16.3 pg/ml was detectable. After 24 and 36 hours, 37 pg/ml and 43.5 pg/ml HGF were measured in the incubated cell cultures, respectively; 72 hours of incubation with VCAM-1 resulted in 50.6 pg/ml HGF, whereas 23.5 pg/ml was determined in the controls. The RT-PCR for HGF also showed increased concentration in the incubated cells after 72 hours. CONCLUSION: VCAM-1 induced an increase in levels of HGF in the ECRS cell cultures. The rising transcriptional activity was demonstrated by means of RT-PCR. The levels of HGF were within physiological ranges, suggesting that a misbalance between HGF and VCAM-1 resulted in the establishment of ECRS. Further experiments are necessary to reveal the role of HGF in the development of ECRS. This is the first report about the effect of VCAM-1 on growth factors in ECRS cell culture.

On the single sweep processing of auditory brainstem responses: click vs. chirp stimulations and active vs. passive electrodes.

We have recently shown that click evoked auditory brainstem responses (ABRs) single sweeps can efficiently be processed by a hybrid novelty detection system. This approach allowed for the objective detection of hearing thresholds in a fraction of time of conventional schemes, making it appropriate for the efficient implementation of newborn hearing screening procedures. It is the objective of this study to evaluate whether this approach might further be improved by different stimulation paradigms and electrode settings. In particular, we evaluate chirp stimulations which compensate the basilar-membrane dispersion and active electrodes which are less sensitive to movements. This is the first study which is directed to a single sweep processing of chirp evoked ABRs. By concentrating on transparent features and a minimum number of adjustable parameters, we present an objective comparison of click vs.chirp stimulations and active vs. passive electrodes in the ultrafast ABR detection. We show that chirp evoked brainstem responses and active electrodes might improve the single sweeps analysis of ABRs.Consequently, we conclude that a single sweep processing of ABRs for the objective determination of hearing thresholds can further be improved by the use of optimized chirp stimulations and active electrodes.