A comparison of inter-aural attenuation with the Etymotic ER-3A insert earphone and the Telephonics TDH-39 supra-aural earphone.

One of the many reported advantages of the insert earphone over the supra-aural earphone is increased inter-aural attenuation (IA). Minimum values of IA determine the need for masking of the non-test ear in air-conduction audiometry. The aim of the present study was to measure inter-aural attenuation for the Etymotic Research ER-3A insert earphone (with deep and shallow insertion of the ear plug within the ear canal) and compare this with the supra-aural Telephonics TDH-39/MX41-AR earphone/cushion combination. Subjects were 18 adults ranging in age from 38 to 68 years (mean 50 years). Each subject had no hearing in one ear following translabyrinthine surgery for removal of an acoustic neuroma. The opposite ear had hearing thresholds better than 40 dB HL and an air-bone gap of less than 10 dB at any audiometric frequency. Pure tone air-conduction thresholds were obtained in the range 0.25-8 kHz. Deep insertion of the insert earphone was deemed to occur when the outside edge of the ear plug was flush with the entrance of the ear canal. Shallow insertion was deemed to occur when half of the ear plug (6 mm) was inside the entrance of the ear canal. IA was defined operationally as the difference between the good-ear and poor-ear not-masked air conduction threshold for a given audiometric frequency and earphone. The results show that the TDH-39/MX41-AR combination provides a median IA of approximately 60 dB with a lower limit of approximately 45 dB. Greater IA was obtained with the ER-3A insert earphone but this depended on the depth of insertion. With a deep insertion, the 1A values were some 15-20 dB greater than with the supra-aural earphone. Although frequency-specific IA values are provided, a simple rule of thumb is to apply masking to the non-test ear when the pure tone airconduction signal from the ER-3A insert earphone exceeds the bone conduction threshold of the non-test ear by 55 dB HL or more. If it is not possible to obtain a deep insertion depth this value should be reduced by 5 dB.     

Reference hearing threshold levels for chirp signals delivered by an ER-3A insert earphone

Abstract

Objective: To establish reference hearing threshold levels for chirps and frequency-specific chirps. Design: Hearing thresholds were determined monaurally for broad-band chirps and octave-band chirps using the Etymotic Research, ER-3A insert earphone. The chirps were presented using two repetition rates, 20 and 90 stimuli/s, and with alternating polarity in blocks of one second duration. The test procedure and test conditions were in accordance with the recommendations given in . The ascending method () was applied using a step size of 5 dB. The chirps were played back from a Tucker Davies Technologies System II, and a Matlab program controlled the test setup. The results are specified in dB peak-to-peak equivalent threshold sound pressure levels (dB peETSPL). Study sample: The test group consisted of 25 otologically-normal young adults (age 18–25 years). Results: The results are in good agreement with the results from another investigation of hearing thresholds using the same chirp stimuli, and the values for the octave-band chirps are in line with the standardized reference values for corresponding tone bursts (). Conclusions: The results of the present investigation are relevant for the international standard on short duration signals, .     

A clinical comparison of Grason Stadler insert earphones and TDH-50P standard earphones.

Recent investigations have reported numerous advantages of insert earphones. However, no data have been reported regarding Grason Stadler (GS) insert earphones. The purpose of this investigation was to compare results obtained using the GS insert earphone to those obtained using a standard earphone on pure-tone thresholds, ipsilateral effective masking levels, and an estimate of interaural attenuation. Twenty-seven normal-hearing listeners participated. Pure-tone thresholds and ipsilateral effective masking levels obtained were not significantly different for the two transducers. However, the GS insert earphones yielded significantly greater interaural attenuation.     

Evidence on the efficacy of insert earphone and sound field VRA with young infants

Visual reinforcement audiometry (VRA) with insert-earphone stimulus delivery provides a means of obtaining early ear-specific information on the auditory status of infants. The aim of this study was to investigate the efficacy of VRA in young infants, and to compare the use of sound field and insert-earphone stimulus presentation. VRA was performed on 41 normally developing infants aged between 20 and 42 weeks. Infants were tested in the sound field (n=22) and with insert earphones (n=19). Results showed significantly more minimum response levels (MRLs) obtained with sound field testing, and with older children. Nevertheless, in the insert-earphone group, 36% of those aged 32 weeks or more gave two or more MRLs, and 25% of the infants aged 25 weeks or less gave one or more MRLs. This study provides data from developmentally normal infants which confirms the efficacy of insert-earphones as well as sound field VRA with 32-42-week-olds, with reasonable expectation of success. The data in this study also suggest that VRA could be usefully employed for younger infants aged approximately 20-26 weeks where information, although less easily obtained, may be of particular value to early diagnosis and habilitation.     

A randomised trial comparing the subjective outcomes following septoplasty with or without inferior turbinoplasty

AimsThe surgical management of contralateral inferior turbinate hypertrophy in patients with deviated nasal septum is controversial. In this randomised clinical trial, we aimed to investigate the subjective improvement of nasal symptoms postoperatively in patients undergoing septoplasty with or without inferior turbinoplasty.Material and methodsOne hundred and thirty-seven patients with nasal obstruction, who had unilateral septal deviation and compensatory contralateral inferior turbinate enlargement, were randomised into either septoplasty alone arm (n = 66) or septoplasty combined with turbinoplasty arm (n = 71). Preoperative symptom scores and the subjective perception of the nasal obstruction were compared between two groups of the study using Nasal Obstruction Symptom Evaluation Scale (NOSE) and Visual analog scale (VAS) respectively. The measurements were repeated 6 months after surgery as well as at 1, 2, and 4 years postoperatively.ResultsWith regard to the findings obtained from both scales, both interventions successfully relieved the patients’ complaints of nasal obstruction at almost all postoperative visits when compared with the baseline measurements (P ˂ 0.005 for most comparisons). However, the relief of nasal obstruction was more pronounced in patients undergoing combined intervention at all postoperative visits, except at the 1st follow-up session (P ˂ 0.005). Nasal symptoms of septoplasty alone group began to deteriorate over the period between month 24 and month 48. In contrast, patients undergoing the combined surgery steadily showed symptomatic improvement over the whole period of study.ConclusionsA turbinate reduction surgery should be conducted along with septoplasty to achieve better results in cases suffering from deviated nasal septum with concomitant hypertrophied inferior turbinate.     

Effects of rotation on the sleep state-dependent midlatency auditory evoked P50 potential in the human

Sopite syndrome, characterized by loss of initiative, sensitivity to normally innocuous sensory stimuli, and impaired concentration amounting to a sensory gating deficit, is commonly associated with Space Motion Sickness (SMS). The amplitude of the P50 potential is a measure of level of arousal, and a paired-stimulus paradigm can be used to measure sensory gating. We used the rotary chair to elicit the sensory mismatch that occurs with SMS by overstimulating the vestibular apparatus. The effects of rotation on the manifestation of the P50 midlatency auditory evoked response were then assessed as a measure of arousal and distractibility. Results showed that rotation-induced motion sickness produced no change in the level of arousal but did produce a significant deficit in sensory gating, indicating that some of the attentional and cognitive deficits observed with SMS may be due to distractibility induced by decreased habituation to repetitive stimuli.     

Saccular laryngeal cysts. Three case studies and review of the literature

Supraglottic laryngeal cysts are benign lesions that usually are easily recognized and simply managed. Among these lesions saccular cysts are uncommon, usually large, anomalies of the larynx and can cause severe airway obstruction and even death. Three patients with a saccular cyst were successfully treated by endoscopic CO(2)-laser excision of their lesions. Before microlaryngoscopy and laser procedure, an urgent tracheostomy was required in 1 of our cases.     

A prospective case-control study of 50 consecutive patients presenting with hyperlipidaemia.

The literature contains many references which refer to a causal relationship between hyperlipidaemia and hearing loss, but the majority of reports lack adequate controls, or are based on a series of cases which may represent incidental findings. This prospective case-control study compared a restricted population of 50 consecutive hyperlipidaemic patients attending a lipid clinic whose fasting lipid levels were > 2 SDs above the population mean with a control population recruited from patients undergoing nasal surgery for structural abnormalities (n = 159). The National Study of Hearing data was also compared with both groups in order to provide external validity to the control group. This study showed no consistent differences in the hearing thresholds of the hyperlipidaemic group compared with either control group. The Null hypothesis that sensorineural hearing loss is no greater in a population whose fasting blood lipids are raised > 2 SDs above the population mean level than in a control population cannot be refuted given the variability of the data.     

The clinical utility of the P3 AERP in children with auditory processing disorders.

This study investigated whether the P3 AERP could be used to reflect behavioral changes resulting from therapeutic intervention in a group of children with central auditory processing disorders (CAPDs). Results showed a significant decrease in P3 latency, along with a significant increase in P3 amplitude, following a structured treatment program. No changes occurred in either the CAPD control group or in the normal control group. These results suggest that the P3 AERP latency and amplitude measures are sensitive to changes in clinical status following a treatment program.     

A meta-analysis comparing outcomes of microsurgery and gamma knife radiosurgery

OBJECTIVES/HYPOTHESIS: Surgery has been the most common treatment for acoustic neuromas, but gamma knife radiosurgery has emerged as a safe and efficacious alternative to microsurgery. This meta-analysis compares the outcomes of the two modalities. STUDY DESIGN: A retrospective MEDLINE search was used to find all surgical and gamma knife studies published from 1990 to 1998 and strict inclusion criteria were applied. RESULTS: For tumors less than 4 cm in diameter, there is no difference in hearing preservation (P = .82) or facial nerve outcome (P = .2). Surgery on all sized tumors has a significantly lower complication rate than radiosurgery performed on tumors smaller than 4 cm (P = 3.2 x 10(-14)). Surgery also has a lower major morbidity rate than gamma knife radiosurgery (P = 2.4 x 10(-14)). Tumor control was defined as no tumor recurrence or no tumor regrowth. Surgery has superior tumor control when tumors are totally resected (P = 9.02 x 10(-11)). Assuming that all partially resected tumors will recur, surgery still retains a significant advantage over radiosurgery for tumor control (P = .028). CONCLUSION: Data from these studies date back to the late 1960s and do not completely reflect outcomes using current imaging and procedures. A major difficulty encountered in this study is inconsistent data reporting. Future surgical and radiation reports should use standardized outcomes scales to allow valid statistical comparisons. In addition, long-term results from gamma knife radiosurgery using lower dosimetry have not been reported. Surgery should remain the therapy of choice for acoustic neuromas until tumor control rates can be established.     

A prospective case–control study of 50 consecutive patients presenting with hyperlipidaemia

The literature contains many references which refer to a causal relationship between hyperlipidaemia and hearing loss, but the majority of reports lack adequate controls, or are based on a series of cases which may represent incidental findings. This prospective case–control study compared a restricted population of 50 consecutive hyperlipidaemic patients attending a lipid clinic whose fasting lipid levels were >2 sd s above the population mean with a control population recruited from patients undergoing nasal surgery for structural abnormalities (n = 159). The National Study of Hearing data was also compared with both groups in order to provide external validity to the control group. This study showed no consistent differences in the hearing thresholds of the hyperlipidaemic group compared with either control group. The Null hypothesis that sensorineural hearing loss is no greater in a population whose fasting blood lipids are raised > 2 sd s above the population mean level than in a control population cannot be refuted given the variability of the data.     

A report of 50 patients with carcinoma of the hypopharynx treated by total pharyngolaryngo-oesophagectomy repaired by gastric transposition

Extensive carcinoma of the hypopharynx requires aggressive surgery, which can lead to loss of function and a high morbidity and mortality. This paper reports 50 patients with carcinoma of the hypopharynx treated with total pharyngolaryngo-oesophagectomy and gastric transposition. Thirty-two patients had primary surgery and 18 had salvage surgery for recurrence following radiotherapy. Two technical modifications to the standard procedure that have evolved during this period are the use of a diverticuloscope for dissection of the middle third of the oesophagus and the routine insertion of chest drains peroperatively. Complications were relatively unusual in the primary surgery group, but were a problem in those patients undergoing salvage surgery. Stenosis did not tend to occur with gastric transposition repair, but three patients had delayed gastric emptying with prolonged hospital stays. The tumour-specific actuarial survival at 4 years was 39% and the observed survival was 25%. Pharyngolaryngo-oesophagectomy and gastric transposition is becoming safer owing to increased multidisciplinary experience in this form of surgery. Survival is improved with the use of postoperative radiotherapy in patients undergoing primary surgery.     

A prospective study comparing PlasmaKnife with bipolar dissection tonsillectomy: a preliminary communication of an emerging technology

Objective: To clinically evaluate and compare the PlasmaKnife to bipolar electrocautery in paediatric tonsillectomy. Design: Prospective comparitive non‐randomised study. Setting: Central London teaching hospital with tertiary referrals. Participants: Forty‐three patients aged 3–12 years with recurrent tonsillitis or obstructive adenotonsillar hypertrophy awaiting a tonsillectomy were recruited into the study. Main outcome measures: Primary outcome was throat, ear and swallowing pain scores over 2 weeks. Secondary measures included: return to normal diet, return to normal activity, analgesic requirements, operation time and intraoperative blood loss. Results: Surgical dissection was similar between the two groups with minimal blood loss and comparable overall operative times. Median throat pain scores suggest PlasmaKnife to be less painful in the early postoperative period (at 8 h, P < 0.005) but, overall, did not quite reach statistical significance (Mann–Whitney U‐test). PlasmaKnife was similar to bipolar in all other measured categories. During the study, three secondary bleeds occurred in the PlasmaKnife group and all were managed conservatively. Conclusion: PlasmaKnife is a safe new technology with similar outcome to the established bipolar technique. This preliminary study finds PlasmaKnife to be an interesting instrument and warrants a larger randomised study to truly evaluate the potential advantages of lowered pain and early recovery attributed to this emerging technology.     

A prospective double-blind randomized controlled trial comparing the suitability of KTP laser tonsillectomy with conventional dissection tonsillectomy for day case surgery

Tonsillectomy using a KTP laser has been performed increasingly but is not a routinely practised technique in the UK. In the USA, tonsillectomy is often performed as a day case procedure but, here in the UK, it is still standard practice to admit patients for overnight stay. We present the largest prospective double-blind randomized controlled trial to date (151 patients) comparing KTP laser with standard dissection tonsillectomy and assess the suitability of both procedures for day case surgery. We found that there was significantly less peroperative haemorrhage if tonsillectomy was performed using the KTP laser, but it did cause more postoperative pain, more depression in mood and a higher rate of both reactionary and secondary haemorrhage, which was not significant when compared with conventional dissection. There was no difference in operating time, and over 40% of patients in each group needed overnight admission. We conclude that KTP laser tonsillectomy offers no benefit apart from less intraoperative bleeding over standard dissection tonsillectomy. Discharge from hospital after tonsillectomy was found to be unpredictable. Tonsillectomy is therefore an unsuitable procedure for planned surgery through a day unit, but approximately 58% of patients could be discharged on the same day from an extended day surgery unit, and the rest have one night in hospital.