Hearing preservation and improved speech perception with a flexible 28-mm electrode.

OBJECTIVE: The present study aimed to determine the extent of hearing preservation retrospectively after atraumatic cochlear implant (CI) surgery using a specialized surgical technique and specially designed flexible electrode to minimize cochlear trauma. STUDY DESIGN: Retrospective study. SETTING: Academic tertiary care center. PATIENTS: A consecutive series of 34 patients who had some preoperative residual hearing were included in this study. INTERVENTION: Patients underwent CI surgery with a flexible 28-mm electrode using a round window insertion technique. MAIN OUTCOME MEASURES: All patients had at least 6 months of postoperative follow-up including audiometric testing and speech perception determined using the Freiburg monosyllable word test and the Oldenburger Sentence Test in noise. Audiometric testing served as a proxy for the evaluation of cochlear trauma and hearing preservation. RESULTS: Hearing was preserved to within 20 dB of preoperative low-frequency pure-tone audiometry (PTA) in 40.7% of patients. Hearing was preserved to within 20 dB of preoperative high-frequency PTA in 35.7% of patients. Overall, a deterioration in hearing thresholds was observed between preoperative assessment and first fitting. Speech perception improved significantly over time after surgery. CONCLUSION: Using appropriate surgical techniques, and electrodes specially designed to minimize cochlear trauma, hearing preservation can be achieved.

Differences in Glycemic Variability Between Normoglycemic and Prediabetic Subjects.

So far the criteria for NGT and abnormal glucose tolerance (AGT) are based on HbA1c and 75 g oGTT. We present data on GV and diurnal profiles in stratified cohorts with AGT versus controls. 28 NGT, 42 AGT (15 IGT, 11 IFG, 16 CGI) matched for age and BMI classified by 75 g oGTT underwent a CGM with test meal (TM). Diurnal profiles, glucose excursion after TM, and GV (SD, MAGE) were calculated for day 2 and 3. HbA1c, with its values of 5.5 ± 0.37% versus 5.65 ± 0.36%, was within normal range. Average interstitial glucose (AiG) was 5.84 ± 0.52 mmol/l) in NGT and 6.35 ± 0.65 mmol/l in AGT (P = .002). The 2 h incremental area under curve (iAUC) from TM until 2 h after TM was 1.94 ± 1.31 mmol/l*h versus 2.89 ( ± 1.75) mmol/l*h (P = .012), AiG 2 hours after TM was 5.99 ± 1.14 mmol/l*d versus 6.64 ± 1.30 mmol/l (P = .035). Peaks of AiG after TM were 7.69 ± 1.48 mmol/l*d versus 9.18 ± 1.67 mmol/l*d (P = .001). SD was significantly higher for AGT (1.12 ± 0.37 vs. 0.85 ± 0.32 mmol/l, P = .01) and MAGE 2.26 ± 0.84 vs. 1.60 ± 0.69 mmol/l, P = .005). In this comparative analysis NGT and AGT well matched for age, BMI, and comorbidities, CGM revealed significant differences in daytime AiG, pp glucose excursion and postprandial peaks. SD and MAGE was significantly higher for subjects with AGT. I Impaired glucose homeostasis a better characterizes degree of AGTe than HbA1c and 75 g OGTT.

Scalar localization by computed tomography of cochlear implant electrode carriers designed for deep insertion.

OBJECTIVES: This study aimed to evaluate the possibility of predicting radiologically the scalar localization of a 31.5-mm-long, free-fitting electrode carrier for cochlear implantation, using conventional planar computed tomography. STUDY DESIGN: A cross-sectional human temporal bone study was conducted. SETTING: Twenty human temporal bones were acquired postmortem and implanted with 31.5-mm-long electrode carriers. Ten of these were implanted into the scala tympani using the round window approach, whereas the other 10 electrodes were inserted into the scala vestibuli by cochleostomy. Computed tomography was then performed, and 2 experienced blinded radiologists evaluated the intracochlear position of the array. MAIN OUTCOME MEASURE: The estimated position of the electrode carrier was described using a 5-point scale. After sectioning and histologic investigation, the results of the radiologic and histologic investigations were compared. RESULTS: In 17 of 20 cases, it was possible to estimate the correct position of the electrode carrier within the basal turn of the cochlea by means of computed tomography. As the insertion angles widened beyond 360 degrees, it became increasing difficult for the radiologists to correctly determine the position of the electrode carrier. CONCLUSION: The comparison of our temporal bone experiment results with the computed tomography results revealed the difficulty of assessing the correct position of intracochlear electrodes. Scalar localization of deeply inserted electrode carriers cannot be precisely determined by means of computed tomography.

Hearing preservation after complete cochlear coverage in cochlear implantation with the free-fitting FLEXSOFT electrode carrier.

OBJECTIVES: To demonstrate the possibility of atraumatic insertion with the free-fitting FLEX electrode by evaluating the degree of hearing preservation postoperatively. DESIGN: Retrospective study. SETTING: Academic tertiary care center. PARTICIPANTS: Twenty-two severely to profoundly hearing impaired subjects with measurable residual hearing preoperatively. INTERVENTION: Atraumatic implantation with the 31.5-mm-long, free-fitting, and highly flexible FLEX electrode using either the round window approach or a cochleostomy technique. MAIN OUTCOME MEASURES: Subjects were tested preoperatively in unaided condition and at varying intervals postoperatively. Preoperative and postoperative low-frequency pure-tone average (PTA) and PTA shifts were calculated. Speech perception was measured preoperatively and postoperatively using the Freiburger monosyllabic word test in quiet. RESULTS: Preoperative low-frequency hearing could be preserved to a certain degree in 77.3% of subjects (17/22) after insertion of the FLEX electrode up to the point of first resistance. Complete loss of residual hearing was observed in 22.7% of subjects (5/22). In 18.2% of the subjects (4/22), the preoperative PTA was preserved within 10 dB. Pure-tone average results between preoperative and most recent testing showed statistically significant differences (p < 0.001 to p = 0.031) for almost all loudness levels ranging from 125 Hz to 1.5 kHz. The maximum threshold shift was 40 dB at 250 Hz for the lower frequencies up to 1 kHz. Monosyllable testing in quiet demonstrated significant improvement over time (p < 0.001). CONCLUSION: This study showed that preservation of residual hearing is possible in a high number of subjects when a flexible electrode and atraumatic surgical techniques are used.

Evaluation of an electrode prototype for atraumatic cochlear implantation in hearing preservation candidates: preliminary results from a temporal bone study.

OBJECTIVES: This study aimed to evaluate an atraumatic prototype electrode carrier for cochlear implantation, the FLEX electrode. This electrode is designed to preserve hearing and to achieve a 360-degree insertion. STUDY DESIGN: A cross-sectional human temporal bone study was conducted. SETTING: Preliminarily, the prototype electrode was inserted in a scala tympani model to measure the insertion force. Thirteen human temporal bones were acquired postmortem and implanted with the new device using the round window approach. Three of them were implanted under radiologic control to demonstrate the insertion path. After embedding, the remaining 10 temporal bones were sectioned undecalcified and examined macroscopically and histologically. MAIN OUTCOME MEASURES: The insertion force was measured to determine intracochlear resistance peaks. The insertion angle was measured, and the degree of intracochlear trauma was determined. RESULTS: The round window approach caused cochlear trauma in 1 of 10 specimens. An exact 360-degree insertion was achieved in 7 of 10 specimens (mean overall insertion angle, 360 degrees). Radiologic examination and insertion force measurements revealed the smooth and atraumatic insertion. CONCLUSION: The new prototype electrode carrier is suitable for clinical application. It can be handled easily and allows atraumatic 360-degree insertion of all electrode contacts. Therefore, this electrode concept allows good coverage of the cochlea for electrical and additional acoustic stimulation.

Certifying a university ENT clinic using the ISO 9001:2000 international standard.

PURPOSE: Against statutory duties to introduce quality management systems, the increased importance of this subject has led to numerous activities in various public health institutions. Following the International Standardization Organization (ISO 9001:2000) prerequisites, Frankfurt Goethe University Hospital ENT clinic staff introduced a quality management system. This paper aims to investigate this process. DESIGN/METHODOLOGY/APPROACH: Designing, planning and implementing the quality management system is described. Under the supervision of an executive quality management board, clinic quality goals were defined. Thereafter, several quality management teams performed an actual state analysis as well as developing and realising improvement proposals. Finally a quality management manual containing binding standards and working instructions concerning all patient care, research and teaching aspects was written. FINDINGS: Successful certification by a neutral body ascertained that the clinic's quality management system conformed to current national and international standards while restructuring and reform improved procedural efficiency. ORIGINALITY/VALUE: The paper shows that mplementing the quality management system requires considerable effort but patients as well as staff profit considerably from the innovation. On the whole, the positive impact on structure and workflow in a specialist clinic predominates. Therefore, implementing a quality management system in all the clinic's wards and departments is recommended.

Clinical requirements for an ultrasound-based tool navigator for minimally interventional procedures.

BACKGROUND: The past years showed a considerable progress in the development of imaging and navigation systems to support minimal-invasive surgery. However, these methods do not always meet actual clinical requirements of surgeons. They often cause technical and logistic efforts and considerable costs. Purpose of our study was the development of a navigation system relying on simple, familiar and cheaper components. It is based on two-dimensional ultrasound visualization, is quickly applicable to a wide range of minimal-invasive interventions, and is easily to be learned. MATERIAL/METHODS: The imaging system is composed of widely used, well-accepted components and relies only upon conventional two-dimensional sonography using a navigated ultrasound probe, a navigated surgical instrument, and a coordinate tracker, combined with new custom-made navigation software. Accuracy tests were performed, possible error sources were mentioned and the easy and safe handling of this system was demonstrated. RESULTS: Our custom-made software integrates information about the three-dimensional position of an instrument into a two-dimensional ultrasonic image. On-screen navigation aids are offered to reach a sonographically depicted target structure. These navigation aids are easily to be learned and make the use of this system very comfortable. The system shows a mean three-dimensional error of only 0.9+/-0.2 mm. CONCLUSIONS: Our navigation system combines several advantages: as to visualization, it relies solely on the familiar two-dimensional ultrasound image, its use is easy, it is more economic than comparable ultrasound navigation systems, and it can be used in a wide range of minimal-invasive interventions.

Cochlear reimplantation after surgery for electric-acoustic stimulation.

BACKGROUND/AIMS: Combined electric-acoustic stimulation (EAS) of the auditory system usually results in better speech understanding than electric stimulation only, assuming low-frequency hearing can be preserved. Treatment options and outcomes for 4 subjects experiencing compromised hearing after EAS surgery are discussed. METHODS: Each subject underwent revision surgery to replace the original 21-mm electrode arrays used in EAS surgery with cochlear implants (CIs) with 31-mm arrays. Our aims were: (1) to investigate whether deeper insertion is possible, and (2) to evaluate the influence of electrode insertion angle by comparing speech perception scores before and after revision surgery. RESULTS: Deeper insertion was feasible in all subjects. Speech understanding scores after reimplantation were comparable to those seen after the first intervention. CONCLUSION: A 360-degree insertion under EAS conditions provides sufficient speech understanding, even in cases of additional hearing loss. Reimplantation with a longer electrode array is feasible in former EAS patients.

Quality management: reduction of waiting time and efficiency enhancement in an ENT-university outpatients' department.

BACKGROUND: Public health systems are confronted with constantly rising costs. Furthermore, diagnostic as well as treatment services become more and more specialized. These are the reasons for an interdisciplinary project on the one hand aiming at simplification of planning and scheduling patient appointments, on the other hand at fulfilling all requirements of efficiency and treatment quality. METHODS: As to understanding procedure and problem solving activities, the responsible project group strictly proceeded with four methodical steps: actual state analysis, analysis of causes, correcting measures, and examination of effectiveness. Various methods of quality management, as for instance opinion polls, data collections, and several procedures of problem identification as well as of solution proposals were applied. All activities were realized according to the requirements of the clinic's ISO 9001:2000 certified quality management system. The development of this project is described step by step from planning phase to inauguration into the daily routine of the clinic and subsequent control of effectiveness. RESULTS: Five significant problem fields could be identified. After an analysis of causes the major remedial measures were: installation of a patient telephone hotline, standardization of appointment arrangements for all patients, modification of the appointments book considering the reason for coming in planning defined working periods for certain symptoms and treatments, improvement of telephonic counselling, and transition to flexible time planning by daily updates of the appointments book. After implementation of these changes into the clinic's routine success could be demonstrated by significantly reduced waiting times and resulting increased patient satisfaction. CONCLUSION: Systematic scrutiny of the existing organizational structures of the outpatients' department of our clinic by means of actual state analysis and analysis of causes revealed the necessity of improvement. According to rules of quality management correcting measures and subsequent examination of effectiveness were performed. These changes resulted in higher satisfaction of patients, referring colleagues and clinic staff the like. Additionally the clinic is able to cope with an increasing demand for appointments in outpatients' departments, and the clinic's human resources are employed more effectively.

A new combined speech processor for electric and acoustic stimulation--eight months experience.

PURPOSE: Electric acoustic stimulation (EAS) relies on the preservation of low-frequency hearing and adequate amplification of these frequencies. EAS has been achieved by fitting the cochlear implant (CI) speech processor together with an ipsilateral in-the-ear hearing aid. This study will evaluate the outcomes when CI/EAS users upgrade to a new combination of hearing aid and speech processor in 1 device (DUET). METHOD: Nine EAS patients participated in this study. Before switchover and after 2 and 8 months of DUET device use, they were assessed using monosyllables and sentences in quiet and in noise. Additionally, a questionnaire, the Abbreviated Profile for Hearing Aid Benefit (APHAB), was used to evaluate subjective impressions. RESULTS: All subjects performed equally well, or even better, after switchover. This was also demonstrated over time. The participants with EAS before switchover performed equally afterwards, while those who used CI only did markedly better with the new device, especially in noisy conditions. Slight preference for the new system was also demonstrated with the APHAB. CONCLUSION: All subjects showed benefit in noise; CI-only users before switchover particularly benefited from the new hearing system. Those who applied EAS before switchover performed equally well. The DUET allows individuals better access to EAS.

Craniofacial reconstructions with bone-anchored epithesis in head and neck cancer patients--a valid way back to self-perception and social reintegration.

BACKGROUND: Patients with advanced head and neck cancer often require radical and mutilating surgery resulting in severe impairment of their aesthetic self-perception and social life. Cosmetically satisfying results associated with high aesthetic self-perception and social reintegration are possible with bone-anchored epithesis representing a serious alternative to craniofacial reconstructive techniques using regional and free tissue transfer. PATIENTS AND METHODS: Five head and neck cancer patients treated in our Ear, Nose and Throat Department in the years 2003-2004 were evaluated after epithesial reconstruction. RESULTS: Three out of the five patients scored self-perception after epithesial reconstruction as "very good", while social integration was scored as "very good" by three and as "satisfactory" by two patients. Daily getting along was scored as "very good" by four and as satisfactory by one patient. One patient had a very good acceptance of the epithesis as a part of the body and for four patients it was satisfactory. CONCLUSION: For the first time, the high degree of satisfaction in head and neck cancer patients receiving epithesial reconstruction in the maxillofacial region is demonstrated.

Development of prototype for navigated real-time sonography for the head and neck region.

BACKGROUND: To date, few imaging methods have been established for the head and neck region, in particular for soft tissues, that allow adequate visualization and simultaneously adequate real-time orientation. METHODS: We report a new method using a navigated ultrasound device and a navigated surgical instrument that allows--even in the absence of bony landmarks--appropriate visualization and reliable orientation in real time. RESULTS: The practical applicability of the system was tested. Good handling and acceptance of the system could be shown. The "3-dimensional error" derived from the deviations in all 3 dimensions lies at 0.64 mm. CONCLUSIONS: With this ultrasound-guided navigated procedure, an accurate approach of soft tissue structures with a surgical instrument is possible. Changes of the situs are represented in real time.

Ex vivo responsiveness of head and neck squamous cell carcinoma to glufosfamide, a novel alkylating agent.

BACKGROUND: Glufosfamide is a novel alkylating agent in which the active metabolite of isophosphoramide mustard is glycosidically linked to beta-D-glucose. Targeting the elevated glucose uptake of tumor cells expressing the SAAT1 glucose transporter, glufosfamide represents an attractive new drug for cancer chemotherapy. The present study investigates the ex vivo responsiveness of Head and Neck Squamous Cell Carcinoma (HNSCC) specimens to glufosfamide. PATIENTS AND METHODS: Twenty-one unselected HNSCC specimens were investigated using a novel ex vivo colony formation assay to determine the epithelial drug response. The individual responsiveness to glufosfamide and to cis-platinum was determined. RESULTS: Five out of 21 evaluable HNSCC specimens were sensitive to glufosfamide. There was a tendency for glufosfamide sensitivity in platinum-resistant specimens and vice versa. CONCLUSION: The effectiveness of glufosfamide observed in the present ex vivo study suggests at least an equipotentiality of glufosfamide in comparison to cis-platinum. The potential clinical usefulness of glufosfamide in HNSCC warrants further evaluation.