Carcinoma of Unknown Primary (CUP) versus CUP Turned to Primary Carcinoma of the Head and Neck-An Analysis of Diagnostic Methods and the Impact of Primary Tumor on Clinical Outcome.

BACKGROUND: The purpose of this study was to analyze the value of different diagnostic methods in detecting the primary site and the impact of primary tumors on the clinical outcome of carcinoma of unknown primary (CUP). METHODS: In this multicenter, retrospective study, 124 patients with true CUP (n = 94) and CUP turned to primary carcinoma (n = 30) were included. Patients with evidence of primary site during the clinical examination were excluded a priori. The diagnostic procedure was comprised of imaging and invasive methods (fine-needle-aspiration, tonsillectomy and panendoscopy). All patients were treated with curative intent. RESULTS: Despite extensive diagnostic workup, the primary site remained unknown in 75.8%. Invasive diagnostic methods showed higher primary detection rates than imaging modalities (15.1% vs. 7.8%). Tonsillectomy and panendoscopy revealed the primary tumor in 14.9% and 15.2% of patients, whereas the detection rates of CT, MRI and FDG-PET-CT were 10.1%, 4.8% and 6.5%, respectively. The occurrence of primary tumors led to a significantly deteriorating 5-year overall survival (p = 0.002) and emerged as survival prognosticator (HR = 2.764, p = 0.003). CONCLUSION: Clinical examination in combination with tonsillectomy and panendoscopy was superior to imaging alone in detecting the primary tumor. When the CUP of patients turned to a primary tumor, clinical outcome was significantly worse than in CUP patients.

Impact of surgeons' experience and the single-shot perioperative antibiotic prophylaxis on outcome in stapedotomy.

BACKGROUND: The aim of this study was to evaluate whether surgeons´ experience and perioperative single-shot antibiotic prophylaxis affect outcome of patients undergoing stapes surgery. PATIENTS AND METHODS: We retrospectively evaluated audiological outcomes and postoperative complications of 538 consecutive patients who underwent stapes surgery at a single tertiary referral center between 1990 and 2017. Effects of different clinical variables, including single-shot antibiotic prophylaxis and surgeons' experience on outcome were assessed. RESULTS: 538 patients underwent 667 stapedotomies and postoperative complication rate was 7.5% (n = 50). Air conduction and air-bone gap closure improved significantly after surgery (14.2 ± 14.8 dB, p = 0.001; 14.5 ± 12.8 dB, p = 0.001). Multivariate analysis revealed that 6 years or less of surgical experience was independently associated with a higher incidence of persisting or recurrent conductive hearing loss (p = 0.033, OR 5.13) but perioperative application of antibiotics had no significant effect on outcome. CONCLUSION: First, clinical outcome regarding persisting or recurrent conductive hearing loss caused by incus necrosis and prosthesis luxation is linked to surgical performance. This underlines the need for a meticulous training and supervision of less experienced surgeons performing stapes surgery. Second, our results do not support the need for perioperative antibiotic prophylaxis in stapes surgery. Potential standard limitations of retrospective cohort studies (selection bias, confusion bias etc.) could play a role in interpreting our results. However, the probability for these limitations is minimized due to the large patient sample.

Eccrine porocarcinoma of the head and neck: Meta-analysis of 120 cases.

BACKGROUND: The aim of the study is to analyze potential prognostic factors and to evaluate therapy strategies regarding clinical outcome in patients with eccrine porocarcinoma (EPC) of the head and neck. METHODS: One hundred and sixteen EPC cases from ninety studies and four authors' EPC cases were included in the meta-analysis. RESULTS: At an average follow up of 20.48 months, the 3-year overall survival and regional recurrence rate were 70.3% and 19.0%, respectively. Patients without surgical treatment had a significantly worse 3-year overall survival. Mohs microscopic surgery led to significantly less occurrence of regional recurrences compared to wide excision. An ulcerating lesion, high mitotic activity, and lymphovascular invasion were significant prognostic factors. CONCLUSION: Surgical resection is the cornerstone in the therapy of EPC and represents the therapeutic modality that offers the best chance of disease-free survival. Due to the high probability of recurrence, close follow-ups are strongly recommended.

Single Sided Deaf Cochlear Implant Users in the Difficult Listening Situation: Speech Perception and Subjective Benefit.

OBJECTIVES: Patients with single-sided deafness (SSD) have great difficulties in listening situations which rely on binaural auditory processing. The purpose of this study was to examine to which extent a cochlear implant (CI) can improve speech perception outcomes in various noisy listening environments. Additionally, the ability to use interaural level differences for sound localization and subjective benefit with the CI were assessed. METHODS: Ten single-sided deaf patients with CI were tested in different loudspeaker configurations with and without the CI. A multi-source noise field (MSNF) with uncorrelated noise from four different directions was used in addition to a setup with the signal from the CI side and noise from the normal-hearing side (SCINNH, azimuth of ±45 degrees). Ten normal-hearing subjects were used as a control for the setup. Speech understanding was measured by an adaptive sentence test (Oldenburg Sentence Test, OLSA) in stationary speech shaped noise and temporally modulated noise to assess the benefit in each listening situation. Sensitivity to interaural level differences was measured in a lateralization experiment. Furthermore, patients completed the Bern Benefit in Single-Sided Deafness (BBSS) questionnaire to assess subjective benefit with the CI. RESULTS: An overall average benefit in speech reception threshold (SRT) of 1.6 dB (±0.6 dB standard error of the mean [SEM]) was observed in the binaural listening condition (with CI) in all conditions. In the MSNF setup thresholds improved by 0.4 dB (±0.5 dB SEM) and in the SCINNH configuration by 2.7 dB (±0.7 dB SEM). The choice of masking noise effect also had a significant effect on the SRT outcome. The lateralization performance of the SSD users was on a par with the normal hearing group. BBSS scores reflect the overall benefit with the CI apparent in the speech test results. CONCLUSION: Patients with single-sided deafness do benefit from a CI in difficult listening environments and are able to localize sound based on interaural level differences. Considering these outcomes, cochlear implantation represents a promising treatment option for patients with single-sided deafness.

Effects of Stimulation Rate With the FS4 and HDCIS Coding Strategies in Cochlear Implant Recipients.

OBJECTIVE: The aim of the present study was to evaluate the effect of stimulation rate on speech perception and sound quality for the fine structure strategy FS4 and the envelope-based strategy high definition continuous interleaved sampling (HDCIS). STUDY DESIGN: Randomized crossover trial with four conditions. SETTING: Tertiary referral. PATIENTS: Twenty-six postlingually deafened adult cochlear implant (CI) recipients were included. INTERVENTION: All subjects were equipped with four coding strategies: FS4 with high rate on the envelope channels (on average 1376 pps/ch), FS4 low rate (750 pps/ch), and HDCIS with the same high and low rates. A "flat-charge map" was used for all four strategies. Only the loudness was balanced between programs. All tests were performed acutely in a double blind manner and a randomized sequence. MAIN OUTCOME MEASURES: Monosyllables in quiet and subjective sound quality. RESULTS: Mean monosyllables scores at 65 dB in quiet were 25.5% correct with HDCIS low rate, 27.2% correct with HDCIS high rate, 25.2% with FS4 low rate, and 33.1% with FS4 high rate. Performance with high stimulation rates was significantly higher than with the low rate settings. Subjective sound quality measured with visual analogue scales showed that for naturalness of speech, the improvement with a high rate version was only evident with the FS4 strategy. In both FS4 and HDCIS, higher stimulation rates elicited a higher pitch and were perceived as less dull than lower rates. CONCLUSION: A high rate of stimulation resulted in better speech recognition in both strategies and a favorable subjective sound quality for FS4 in all tested settings.

A New Transcutaneous Bone Conduction Hearing Implant: Short-term Safety and Efficacy in Children.

OBJECTIVE: To investigate the safety and efficacy of a new bone conduction hearing implant in children, during a 3-month follow-up period. STUDY DESIGN: Prospective, single-subject repeated-measures design in which each subject serves as his/her own control. SETTING: Otolaryngology departments of four Austrian hospitals. PATIENTS: Twelve German-speaking children aged 5 to 17 suffering from conductive or mixed hearing loss, with an upper bone conduction threshold limit of 45 dB HL at frequencies between 500 and 4000 Hz. INTERVENTION: Implantation of the Bonebridge transcutaneous bone conduction hearing implant (tBCI). MAIN OUTCOME MEASURES: The subjects' audiometric thresholds (air conduction, bone conduction, and sound field at frequencies 500 Hz to 8 kHz) and speech perception (word recognition scores [WRS] and 50% word intelligibility in sentences [SRT50%]) were tested preoperatively and at 1 and 3 months postoperatively. The patients were also monitored for adverse events and they or their parents filled out questionnaires to analyze satisfaction levels. RESULTS: Speech perception as measured by WRS and SRT50% improved on average approximately 67.6% and 27.5 dB, respectively, 3 months after implantation. Aided thresholds also improved postoperatively, showing statistical significance at all tested frequencies. Air conduction and bone conduction thresholds showed no significant changes, confirming that subjects' residual unaided hearing was not damaged by the treatment. Only minor adverse events were reported and resolved by the end of the study. CONCLUSION: Safety and efficacy of the new bone conduction implant was demonstrated in children followed up to 3 months postoperatively.

Indication criteria and outcomes with the Bonebridge transcutaneous bone-conduction implant.

OBJECTIVES/HYPOTHESIS: The aim of this study was to evaluate functional hearing gain, speech understanding, and preoperative bone-conduction thresholds with the bone-conduction implant Bonebridge. STUDY DESIGN: Retrospective study at a tertiary referral center. METHODS: Twenty-four consecutive Bonebridge patients were identified. Nine patients suffered from combined hearing loss (HL), 12 from atresia of the external auditory canal and three from single-sided deafness. One patient was lost to follow-up. Twenty-three patients were therefore analyzed. RESULTS: The overall average functional hearing gain of all patients (n = 23) was 28.8 dB (±16.1 standard deviation [SD]). Monosyllabic word scores at 65 dB sound pressure level in quiet increased statistically significantly from 4.6 (±7.4 SD) percentage points to 53.7 (±23.0 SD) percentage points. Evaluation of preoperative bone-conduction thresholds revealed three patients with thresholds higher than 45 dB HL in the high frequencies starting at 2 kHz. These three patients had a very limited benefit of their bone-conduction implants. CONCLUSIONS: The Bonebridge bone-conduction implant provides satisfactory results concerning functional gain and speech perception if preoperative bone conduction lies within 45 dB HL. LEVEL OF EVIDENCE: 4.

FS4, FS4-p, and FSP: a 4-month crossover study of 3 fine structure sound-coding strategies.

OBJECTIVES: The aim of the present study was to compare two novel fine structure strategies "FS4" and "FS4-p" with the established fine structure processing (FSP) strategy. FS4 provides fine structure information on the apical four-electrode channels. With FS4-p, these electrodes may be stimulated in a parallel manner. The authors evaluated speech perception, sound quality, and subjective preference. DESIGN: A longitudinal crossover study was done on postlingually deafened adults (N = 33) who were using FSP as their default strategy. Each participant was fitted with FS4, FS4-p, and FSP, for 4 months in a randomized and blinded order. After each run, an Adaptive Sentence test in noise (Oldenburger Sentence Test [OLSA]) and a Monosyllable test in quiet (Freiburger Monosyllables) were performed, and subjective sound quality was determined with a Visual Analogue Scale. At the end of the study the preferred strategy was noted. RESULTS: Scores of the OLSA did not reveal any significant differences among the three strategies, but the Freiburger test showed a statistically significant effect (p = 0.03) with slightly worse scores for FS4 (49.7%) compared with FSP (54.3%). Performance of FS4-p (51.8%) was comparable with the other strategies. Both audiometric tests depicted a high variability among subjects. The number of best-performing strategies for each participant individually was as follows: (a) for the OLSA: FSP, N = 10.5; FS4, N = 10.5; and FS4-p, N = 12; and (b) for the Freiburger test: FSP, N = 14; FS4, N = 9; and FS4-p, N = 10. A moderate agreement was found in the best-performing strategies of the Speech tests within the participants. For sound quality, speech in quiet, classical, and pop music were assessed. No significant effects of strategy were found for speech in quiet and classical music, but auditory impression of pop music was rated as more natural in FSP compared with FS4 (p = 0.04). It is interesting that at the end of the study, a majority of the participants favored the new coding strategies over their previous default FSP (FSP, N = 13; FS4, N = 13; FS4-p, N = 7). CONCLUSIONS: In summary, FS4 and FS4-p offer new and further options in audio processor fitting, with similar levels of speech understanding in noise as FSP. This is an interesting result, given that the strategies' presentation of temporal fine structure differs from FSP. At the end of the study, 20 of 33 subjects chose either FS4 or FS4-p over their previous default strategy FSP.

Vibroplasty in mixed and conductive hearing loss: comparison of different coupling methods.

OBJECTIVES/HYPOTHESIS: To evaluate modified coupling techniques of the Vibrant Soundbridge system in patients with mixed and conductive hearing loss and to compare it with conventional vibroplasty. STUDY DESIGN: Retrospective study. METHODS: Two different groups were evaluated: 1) nine cases of conventional incus vibroplasty in comparison with 2) nine patients with modified coupling of the floating mass transducer. In the modified coupling approach, the vibrant floating mass transducer was attached to 1) the stapes/oval window, 2) the round window, or 3) the drilled promontory bone (promontory fenestration window). In three patients, an additional ossiculoplasty was performed. Preoperative and postoperative aided and unaided pure-tone and free-field audiometry and Freiburg monosyllabic word test were used to assess hearing outcome. RESULTS: Functional hearing gain obtained in patients with mixed and conductive hearing loss who underwent modified coupling was 39 dB. Patients with pure sensorineural hearing loss who received conventional incus coupling showed a functional hearing gain of 25 dB. Average functional gain was 41 dB in the oval window group, 45 dB in the round window group, and 30 dB in the promontory fenestration window group. Word recognition test revealed an average improvement of 51% and 21% in the modified and in the conventional approach, respectively. CONCLUSIONS: Modified vibroplasty is a safe and effective treatment for patients with conductive and mixed hearing loss. Coupling the floating mass transducer to the promontory bone (promontory fenestration window) is a viable option in chronically disabled ears if oval and round window coupling is not possible. LEVEL OF EVIDENCE: 4.

Tenotomy of the stapedius and tensor tympani muscles reduces subjective dizziness handicap in definite Meniere's disease.

CONCLUSION: Tenotomy is a promising surgical alternative with a high reduction in dizziness handicap in the short and long term. OBJECTIVES: To investigate the immediate and the long-term effect of tenotomy of the stapedius and tensor tympani muscles on subjective dizziness as measured by the Dizziness Handicap Inventory (DHI). METHODS: A retrospective follow-up study of 42 patients with definite, unilateral Meniere's disease (19 males, 23 females, average age = 58.1 ± 14.1 years) had undergone tenotomy under general anesthesia through an endaural approach. Pre- and postoperative DHI values were compared for all patients, with postoperative follow-up ranging from 6 months to 9 years. Additionally, results were divided into three postoperative subgroups (A = 0-3 years, B = 3-6 years, C = 6-9 years). RESULTS: A statistically significant reduction of 48 DHI points, from a median preoperative DHI = 52 to DHI = 4 postoperatively, was noted (p < 0. 001). In all, 40/42 patients reported a reduction of dizziness handicap, while in 33/42 the difference was > 12 points. A statistically significant reduction of DHI scores was noted (A = 60, B = 34, C = 33) in all subgroups. It was also noted that the higher the preoperative DHI score, the greater the subjective success of the surgery.

Tenotomy of the middle ear muscles causes a dramatic reduction in vertigo attacks and improves audiological function in definite Meniere's disease.

CONCLUSIONS: Because the presented data reveal an immediate and persistent reduction of vertigo and a clear improvement in hearing function and functional scales, we conclude tenotomy to be effective in unilateral, definite Meniere's disease - laying the foundation for future prospective, randomized controlled trials. OBJECTIVES: This study compares the unique long-term results of tenotomy of the stapedius and tensor tympani muscles in definite Meniere's disease refractory to medical treatment and presents a hypothesis on why tenotomy seems effective. METHODS: This was an interventional cohort study. The study sample comprised 30 patients (15 males, 15 females; average age 57 ± 13.1 years) with definite Meniere's disease (AAO-HNS criteria, 1995). Patients were evaluated pre- and postoperatively using pure tone audiometry, AAO-HNS questionnaires regarding vertigo attacks, functional level scores, and tinnitus, and were followed up for 2-9 years. Postoperative values were calculated for the patient collective as a whole and consequently divided into three equal postoperative terms of 3 years each. RESULTS: A statistically significant improvement of inner ear hearing levels postoperatively (p = 0.041) and a major reduction in vertigo attacks in all groups (p < 0.001) with complete absence of attacks in 26/30 patients was noted. Results remained constant up to 9 years postoperatively. Although tinnitus persisted, the intensity was lower overall (p = 0.013).

Envelope versus fine structure speech coding strategy: a crossover study.

OBJECTIVE: The transmission of fine structure information to cochlear implant users is an expanding area of research. Previous studies comparing the fine structure processing (FSP) speech coding strategy to the envelope-based continuous interleaved sampling (CIS) strategy indicated improved speech perception when using the fine structure strategy. Those investigations were performed with an extended frequency spectrum in the low frequencies together with the fine structure strategy. The current study addresses the question whether these improvements are due to the presentation of fine structure per se or rather the extended frequency spectrum. Hence, this cross over study compares the two strategies using an identical frequency spectrum. STUDY DESIGN: Randomized crossover study. PATIENTS: 31 patients were randomly assigned to two groups. INTERVENTIONS: One group was fitted with a CIS map for 4 weeks, tested and subsequently fitted with a FSP map for 4 weeks. The other group followed the same pattern in reverse. MAIN OUTCOME MEASURES: Test material consisted of sentence tests in noise, monosyllables in quiet and melody recognition. RESULTS: No statistical significance was noted between the different speech coding strategies at an identical frequency spectrum. CONCLUSION: This study shows that there is no difference in speech perception with FSP compared to CIS at an extended frequency spectrum. Therefore, the extended frequency spectrum in the low frequencies might explain a benefit of FSP observed in previous studies.

Residual hearing preservation using the suprameatal approach for cochlear implantation.

OBJECTIVE: Cochlear implantation of patients with high-frequency hearing loss and residual low-frequency hearing has become a new treatment standard within the last years. The objective of this study was to evaluate the rate of hearing preservation in cochlear implantation for electric-acoustic stimulation using the suprameatal approach. METHODS: Five patients (mean age 48.2 years) who were supplied with Med El (Combi 40+, Pulsar) cochlear implants and various different electrodes (Custom made, Flex soft, Flex EAS) were evaluated for residual hearing preservation after a mean follow-up time of 35.6 months (range 24 to 77 months). RESULTS: Three patients showed partial hearing preservation, whereas 2 patients experienced a complete loss of residual hearing. CONCLUSION: Although hearing preservation rates in this series of patients operated on using the suprameatal approach were inferior as compared with a series using the standard mastoidectomy approach, this study shows that it is in fact possible to preserve residual hearing using a non-mastoidectomy surgical technique for cochlear implantation. Nevertheless, more experience is necessary to answer the question whether this technique can be thoroughly recommended in cochlear implantation for electric-acoustic stimulation.

Effects of fine structure and extended low frequencies in pediatric cochlear implant recipients.

OBJECTIVE: In recent years, new speech coding strategies have been developed with the aim of improving the transmission of temporal fine structure to cochlear implant recipients. This study reports on the implementation of one such strategy (fine structure processing, FSP) in children. METHODS: This was a prospective study investigating the upgrade to a new speech processor. The upgrade used a repeated measures design with an alternating order of conditions (A-B-A-B design). Twelve pre- and perilingually deaf children with MED-EL C40+ cochlear implants were enrolled in the study. Patients were upgraded from their Tempo+ speech processor, which used continuous interleaved sampling (CIS) in combination with a frequency spectrum of 200-8500 Hz, to an Opus speech processor, which used FSP with an extended frequency spectrum of 70-8500 Hz. The primary means of testing was an HSM (Hochmair, Schulz and Moser) sentence test at 65 and 80 dB in quiet. In addition, the "Mainzer Kindersprachtest" (Mainz audiometric speech test for children) was applied at 65 and 70 dB. RESULTS: When the new FSP speech processor was used together with the extended low frequency range, HSM sentence tests at 65 and 80 dB resulted in scores indicating statistically significant improvements of 7.1 and 9.9 percentage points, respectively. Scores in the "Mainzer Kindersprachtest" at 65 and 70 dB indicated statistically significant improvements of 9.3 and 6.1 percentage points, respectively. CONCLUSIONS: The present study clearly shows that children benefit from the fine structure speech coding strategy in combination with an extended frequency spectrum in the low frequencies, as is offered by the Opus speech processors. This should be taken into consideration when fitting pre- and perilingually deaf children implanted almost a decade previously.

Tenth and twelfth nerve palsies in a patient with internal carotid artery dissection mistaken for cervical mass lesion.

Among the multiple causes for cranial nerve palsies, internal carotid artery dissection is rather uncommon. Patients usually present with unilateral head pain, Horner's syndrome, and signs of cerebral ischemia. We present the case of a 52-year-old male patient, who showed isolated palsies of the tenth and twelfth nerve without any other symptoms. Magnetic resonance imaging (T1) depicted a hyperintense lesion surrounding the internal carotid artery, which was mistaken for a cervical mass, and the patient underwent unnecessary surgical exploration of the neck. Angiography performed afterward could reveal the dissection of the internal carotid artery. This case shows that even in cases with mild and atypic symptoms, internal carotid artery dissection has always to be ruled out in lower cranial nerve palsies.

Electric acoustic stimulation in patients with postlingual severe high-frequency hearing loss: clinical experience.

BACKGROUND/AIMS: The aim of this study was to describe audiological outcomes and surgical considerations in electric acoustic stimulation for patients with severe to profound high-frequency hearing loss. METHODS: In this latest series of patients in our center, all patients were supplied with the new (atraumatic) Flex EAS MED-EL electrode. Eleven patients (age 7.62-71.32 years) with profound high-frequency hearing loss were implanted with this electrode, which was designed to preserve residual hearing despite the intracochlear insertion of an electrode array. All patients were operated on by the same surgeon (W.G.). RESULTS: The rate of complete or partial hearing preservation was 100% after a mean follow-up period of 7.85 months (range 0.95-15.65 months). CONCLUSION: This study proves that both refined surgical techniques and atraumatic electrodes are mandatory to preserve residual hearing after cochlear implantation. Flexible, thin, and free-fitting straight electrodes, such as the MED-EL Flex EAS electrode used in this study, seem to most accurately meet the requirements for hearing preservation in electric acoustic stimulation.

1-year results using the Opus speech processor with the fine structure speech coding strategy.

CONCLUSION: In contrast to the Tempo+ the new Opus speech processor stimulates with the new fine structure programming (FSP) speech coding strategy and offers an extended frequency spectrum. A significant improvement in speech perception for sentences at 10 dB SNR (signal to noise ratio) was observable. OBJECTIVES: The aim of this study was to investigate the long-term effects on speech perception in quiet and in noise with the Opus speech processor using FSP. SUBJECTS AND METHODS: Eight post-lingually deaf patients implanted with Pulsar cochlear implants and fitted with Tempo+ speech processors (both MED-EL) for a minimum of 1 year were tested at baseline with Tempo+ using continuous interleaved sampling (CIS), and at 1 year follow-up with the Opus speech processor using FSP. Monosyllables and sentence tests were performed in quiet, and sentence tests (HSM) in noise with 15, 10 and 5 dB SNR. RESULTS: Mean speech perception scores showed a trend towards improvement for all tests. A statistically significant (p < 0.05) improvement was only observed for the sentence test in noise at 10 dB SNR.

Surgical revision of hemorrhage in 8388 patients after cold-steel adenotonsillectomies.

PURPOSE OF THE INVESTIGATION: Tonsillectomy and adenoidectomy are the most common surgical procedures in otorhinolaryngology. The most serious complication is postoperative hemorrhage, with a 2-4% risk of substantial bleeding. The aim of this study was to evaluate the incidence of and possible predictive factors for postoperative hemorrhage requiring surgical revision in patients undergoing cold dissection tonsillectomy/adenoidectomy. BASIC PROCEDURES: We performed a single-institution retrospective study of 8388 patients who underwent tonsillectomy and/or adenoidectomy between 1994 and 2006. Tonsillectomy was performed using only cold-steel dissection with bipolar diathermy for hemostasis. MAIN FINDINGS: Hemorrhage occurred in 114 patients (1.78%) after tonsillectomy and in seven patients (0.35%) after adenoidectomy. After tonsillectomy 85.09% of the hemorrhages were secondary, occurring between the postoperative days 1 and 15, whereas in the adenoidectomy group 85.71% of the bleeding episodes were primary. Two patients (0.03%) required blood transfusions, none of the patients required an external carotid artery ligation, and there were no cases of death in our series. On the basis of logistic regression analysis, patient age was found to be a statistically significant risk factor (P = 0.007): the highest incidence was found in patients over 16 years of age (2.19%). At warmer times of year the incidence was higher (1.98%) than at colder times (1.63%). The resident surgeons caused a hemorrhage incidence of 1.75% and the consultant surgeons one of 1.84%. The incidence was significantly higher in male patients (2.2%) than in female patients (1.4%; P = 0.016). PRINCIPAL CONCLUSIONS: Our data show that whereas adenoidectomy can be safely performed as a one-day procedure, tonsillectomy complications due to postoperative hemorrhages might be avoided only if patients were to stay in hospital until postoperative day 15, which would clearly be impractical for economic, organizational and social reasons. A crucial factor for increasing the safety of this procedure is the provision of meticulous education and information for the patient and/or parents.

A new fine structure speech coding strategy: speech perception at a reduced number of channels.

OBJECTIVE: One of the most commonly used speech coding strategies for cochlear implants is continuous interleaved sampling (CIS), which codes the envelope information of an acoustic signal. Based on this strategy, MED-EL has recently developed the new fine structure processing (FSP) speech coding strategy, which also transmits subtle pitch and temporal cues. The aim of this study was to investigate the number of active channels necessary for good speech perception with FSP and whether there is an advantage for FSP compared with CIS at a reduced number of channels. METHODS: Ten postlingually deafened patients using MED-EL Pulsar cochlear implants participated in this study. Patients were tested with all 12, 8, 5, 3, and 2 channels with CIS and FSP strategy, resulting in a total of 10 conditions. Performance was tested with numbers, monosyllables, and sentence tests. RESULTS: Our results showed an improvement in speech perception, with up to 5 channels for numbers and for monosyllables and sentence tests. Statistically significant increases in performance were noted from 3 to 8 channels for numbers, from 3 to 5 channels for monosyllables, and from 5 to 8 channels for sentence tests. No statistical significance was observed whether FSP or CIS was used. CONCLUSION: Based on these findings, the number of channels necessary for speech perception with FSP is similar to published results using CIS. There seems to be no advantage for FSP compared with CIS in the conditions of the present experiment.

The intensity-pitch relation revisited: monopolar versus bipolar cochlear stimulation.

OBJECTIVE/HYPOTHESIS: The very high speech perception scores now being achieved with cochlear implants have led to demands for similar levels of achievement in music perception and perception in noisy environments. One of the crucial factors in these fields is pitch perception. The aim of the present study was to investigate the extent to which pitch perception is influenced by the intensity of the stimulus, through the use of different stimulation modes (monopolar, bipolar) and different electrodes (lateral and perimodiolar). STUDY DESIGN: Sixteen postlingually deafened patients with an average implant use of 3.1 years were included in this study. All patients were using a Cochlear (CI24M, CI24R, CI24RE) cochlear implant. METHODS: Subjects were asked to compare the pitch of an intensity-constant reference tone with the pitch of a test tone of varying intensity. The test was repeated for apical, mediocochlear, and basal channel locations, and also for monopolar and bipolar stimulation. RESULTS: It was found that in monopolar stimulation 87.5% and in bipolar stimulation 85.7% of the patients perceived a clear pitch change with changing intensity of the stimulus (Spearman correlation coefficients r < -0.3 or r > 0.3, respectively). A total of 73.1% of these patients perceived lower pitches with increasing intensity, 26.9% reported the opposite effect. No statistically significant difference in the intensity-pitch correlation could be found between mono- and bipolar stimulation. Neither the mean dynamic range nor the type of electrode used was found to be related to the correlation coefficient. CONCLUSION: Although the majority of today's cochlear implant recipients perform well and the intensity-pitch relation in cochlear implant recipients is still poorly understood, rising demands on speech-coding strategies may soon make a compensation of the pitch shifts desirable. Although the results of our study tend to argue against a peripheral mechanism, the exact origin of this phenomenon remains unclear.