Indirect costs, cost-utility variations and the funding of paediatric cochlear implantation

OBJECTIVE

To demonstrate the existence of variations in cost-utility associated with indirect costs in paediatric cochlear implantation; to illustrate the implications of this for purchasing decisions and; to posit a potential solution to anomalies in purchasing that may otherwise result when services are publicly funded.

METHODS

Data was taken from published sources on the cost of implantation, outcomes measured in terms of quality adjusted life years (QALY) and in savings in education costs associated with paediatric cochlear implantation. Cost-utility ratios across education authorities were calculated using a single centre's implantation costs.

RESULTS

Variations in savings across education authorities show that the cost per QALY gain associated with paediatric cochlear implantation can vary between approximately $12,000 and $18,000 assuming an exchange rate of $1.45 = 1 pound sterling for the same implant centre. These variations have the potential to produce situations in which less efficient implant centres are preferred by purchasers over more efficient ones or in which candidates with poorer outcomes are selected for funding over candidates with superior outcomes. It is important that savings associated with education be taken into consideration in evaluations intended to inform purchasing decisions regarding implantation. Equally it is important that potentially anomalous decisions be avoided if evaluations are to remain credible. It is argued that this may be achievable if public funding for implantation is determined at a national level and ring-fenced i.e. devoted exclusively to use in cochlear implantation.

Pediatric cochlear implantation: the parents' perspective

OBJECTIVE

To analyze parental views on cochlear implantation, before and in the years following implantation, to determine whether the results from the intervention met their expectations.

DESIGN

Prospective longitudinal study to assess parental perspectives of an unselected group of children with cochlear implantation.

SETTING

Tertiary referral pediatric cochlear implant center in the United Kingdom.

SUBJECTS

Forty-three parents of children with cochlear implantation.

INTERVENTION

A specifically designed questionnaire was administered to assess preimplant expectations and observed changes and concerns at 1, 2, and 3 years following implantation. Three key domains were evaluated: (1) communication with others, (2) listening to speech without lipreading, and (3) the development of speech and language.

RESULTS

Preoperative expectations were met or surpassed at each of the follow-up intervals. In the area of communication, 35 (81%) parents expected a definite improvement preoperatively, and 3 years following implantation, 42 (98%) actually saw such an improvement. The respective numbers in the area of listening to speech were 15 (35%) and 38 (88%), and for speech development, 37 (86%) and 37 (86%). Speech development was the major area of concern at all intervals.

CONCLUSION

This study demonstrates the ability of cochlear implantation to meet or surpass parental expectations in 3 important outcome domains: communication, listening to speech, and the development of speech and language.

Use of the telephone in prelingually deaf children with a multichannel cochlear implant

OBJECTIVE

To assess progress in the use of the telephone in a group of prelingually deaf children after cochlear implantation.

SETTING

Tertiary referral pediatric cochlear implant center in the U. K.

STUDY DESIGN

A prospective study was undertaken on a consecutive group of 150 congenital and prelingually deaf children up to 5 years after implantation. The study group was confined to prelingually deaf children aged less than 7 years at the time of implantation. No child was lost to follow-up, and there were no exclusions from the study. At the time of the study, 129 children had reached the 1-year stage, and 91, 68, 40, and 23 had reached the 2-, 3-, 4-, and 5-year intervals, respectively.

METHODS

A specifically designed profile was used to assess the telephone use of the implanted children. Regression analysis was used to assess the correlation between the results of the telephone profile with the outcomes of the Iowa sentence test and connected discourse tracking.

RESULTS

After implantation, prelingually deaf children showed significant progress in telephone use over time, not reaching a plateau at the 5-year interval (median score 27 with maximum score available 34). The results of the telephone profile showed significant correlations with the other tests of speech perception (correlation coefficients from 0.47 to 0.79, all statistically significant p < 0.0001).

CONCLUSION

The telephone profile provided a useful method of monitoring children's telephone use. The profile was easily administered, and it was sensitive in assessing the progress of prelingually deaf children with cochlear implants. Outcomes from the profile were highly correlated with results from other widely used closed- and open-set tests.

Impact of facial paralysis on patients with acoustic neuroma

OBJECTIVE

To assess the psychological distress, the ways of coping with that stress, and the self-esteem of patients with facial paralysis after acoustic neuroma surgery. Possible predictors and associations between these measures were also explored.

STUDY DESIGN

Four validated questionnaires were completed by patients with facial paralysis after acoustic neuroma surgery: 1) the Derriford Appearance Scale (DAS) to measure psychological distress, 2) the COPE questionnaire to measure how patients cope with facial paralysis, 3) the Personal Report questionnaire to measure the self-esteem of patients, and 4) the Facial Paralysis Questionnaire (FPQ) to measure the severity of facial paralysis.

PATIENTS

One hundred three patients with facial paralysis after surgical removal of acoustic tumors.

RESULTS

Distress spanned a wide range in these patients. There was no statistically significant association between the level of distress and the grade of facial paralysis or between time since operation and levels of distress. Women had higher levels of distress (P = .02) and a significant negative correlation was found between levels of distress and age (r = -0.28, P = .005). High levels of distress were associated with low levels of self-esteem, as shown by the significant negative correlation between level of distress and self-esteem (r = -0.59, P = .01). A significant correlation between distress and maladaptive coping (r = 0.31, P = .002) was also found. Stepwise multiple regression of the distress scores revealed that self-esteem was the most important contributing factor (standardized coefficient beta -0.60, P = .0001), followed by age (beta -0.24, P = .006) and sex (beta -0.21, P = .04). This model explained 44% of the distress variance.

CONCLUSION

Clinicians must be aware of the distress felt by some patients experiencing facial palsy after acoustic neuroma surgery and that the level of distress may not be related to the clinical grade of the facial nerve paralysis. People with low self-esteem, young people, and women suffer from more distress due to the facial palsy. Clinicians should thoroughly counsel patients before and after surgery and should implement measures that increase patients' self-esteem and decrease their distress, especially in these high-risk groups.

Determinants of speech perception in children after cochlear implantation

BACKGROUND

Cochlear implants provide access to the speech signal in those profoundly deaf children who derive no material benefit from acoustic hearing aids. Speech perception after implantation can vary widely--we have analysed the contribution of several factors.

METHODS

We examined 40 children with mean age at implantation of 52 months who were either born deaf or became deaf before 3 years. All patients received the same multichannel implant system and were followed up for 5 years. We used connected discourse tracking (CDT) as the measure of speech perception. The effect of five potential predictors (age at implantation, number of inserted electrodes, origin of deafness, mode of communication, and socioeconomic group) on speech perception was analysed.

FINDINGS

The mean number of words per minute perceived increased from 0 before implantation to 44.8 (SD 24.3) 5 years after implantation. Repeated-measures ANOVA showed that children significantly progressed over time (p=0.001). Age at implantation was a significant covariate (p=0.01) and mode of communication was a significant between-individuals factor (p=0.04).

INTERPRETATION

Young age at intervention and oral communication mode are the most important known determinants of later speech perception in young children after cochlear implantation. Early identification of candidate children necessitates implementation of universal neonatal screening programmes for hearing impairment.

Approach to communication, speech perception and intelligibility after paediatric cochlear implantation

The aim of this study was to explore the relationship between approach to communication, speech perception and speech intelligibility after cochlear implantation of young children with profound early deafness. A prospective speech perception and speech intelligibility assessment was undertaken on a consecutive group of implanted children. There were 46 children at the three-year, 26 at the four-year and 20 at the five-year intervals. All had been born deaf or deafened before the age of three and received cochlear implants before the age of seven. Their speech perception ability and the intelligibility of their speech were measured before cochlear implantation and annually thereafter. The children's communication had been classified by their teachers of the deaf at each interval into one of two categories: those using an oral approach and those using a signing approach. Results revealed that at all intervals, those children classified as using oral communication significantly exceeded those using signed communication on measures of speech perception and intelligibility (p<0.05). When those children who had changed from signed to oral communication were compared at the three-year interval with those who used oral communication throughout, there was no significant difference in their results. However, it remains to be explored whether children use oral communication after cochlear implantation because they are doing well, or whether they do well because they are using oral communication.

The prognostic value of promontory electric auditory brain stem response in pediatric cochlear implantation

OBJECTIVE

To test the hypothesis that children with clear promontory electrically evoked auditory brain stem responses (prom-EABRs) would outperform, after cochlear implantation, children who had no prom-EABR preoperatively.

DESIGN

A prospective study was undertaken on 47 implanted children assigning them to two groups (group A: 35 children with a clear wave e-V in the preoperative prom-EABR and group B: 12 children with no prom-EABR). Speech perception and speech intelligibility were assessed annually up to 3 yr after implantation with the IOWA sentence test (level A and level B), Connected Discourse Tracking, Categories of Auditory Performance, and Speech Intelligibility Rating. t-test and Mann-Whitney U test were used to compare the above outcome measures in the two groups.

RESULTS

There was no statistically significant difference between the two groups on any of the outcome measures at any interval. Moreover, the small differences observed showed no consistent trend toward either group of children. Further analysis revealed that the outcomes have not been affected by possible confounding factors (age at implantation, duration of deafness, preoperative unaided pure-tone thresholds, and number of inserted electrodes).

CONCLUSIONS

The results suggest that children with no prom-EABR performed at levels comparable with children who had clear promontory responses preoperatively. The prognostic value of prom-EABR is limited and absence of a prom-EABR is not, by itself, a contraindication for cochlear implantation. However, in selected cases (congenital malformations, cochlear nerve dysplasia or suspected aplasia, narrow internal auditory canal, etc.) the presence of a prom-EABR is a positive finding in the assessment of candidates for cochlear implantation as it confirms the existence of intact auditory neurones.

Impairments, disabilities, and handicaps after acoustic neuroma surgery

The measurement of a patient's health-related quality of life following acoustic neuroma surgery is important because the surgery itself can impose significant symptoms postoperatively. This study describes the most common problems experienced by the patients, using an open-ended questionnaire mailed to a series of 70 patients who had undergone acoustic neuroma surgery. Patient responses were classified by impairment, disability and handicap, according to the World Health Organization (WHO) classification. Results showed that this group of patients had a wide variety of symptoms and concerns, and particularly highlighted the relative importance of visual (49% of the patients) and psychosocial problems (34% of the patients) associated with surgery in contrast to tinnitus that seemed to be of minor importance. Open-ended questionnaires are useful in assessing outcomes from a quality of life perspective.

The development of auditory perception in children following cochlear implantation

The time course for the development of auditory perception in prelingually deaf children following cochlear implantation may extend over many years, thus making long-term studies necessary to evaluate any such outcome. However, few such studies exist in the literature. We prospectively followed-up a consecutive group of 133 prelingually deaf children up to 6 years following implantation. All children were prelingually deaf with age at onset of deafness < 3 years and age at implantation < 8 years. The aetiology of deafness was meningitis for 45 children (34%), congenital deafness for 77 children (58%) and other causes for 11 children (8%). All were implanted with a Nucleus-22 multi-channel cochlear implant and followed the same rehabilitation programme. No child was lost to follow-up and there were no exclusions from the study. Prelingually deaf children showed significant improvement in the auditory perception with implant experience. 82% of children who reached the 6-year interval could understand conversation without lip-reading. The respective percentage in the 4-year interval was 70%. The long-term results of cochlear implantation reveal that the majority of prelingually deaf children, when implanted before the age of 8 years, will develop significant auditory perception.

Cochlear implants in young children: the relationship between speech perception and speech intelligibility

OBJECTIVE

To determine the relationship between measures of speech perception and speech production after cochlear implantation of young children with profound congenital and prelingual deafness.

DESIGN

A prospective study was undertaken on a consecutive group of children with profound deafness. There were 126 children at the preimplantation interval and 71, 50, 26, and 20 children, respectively, at the 2, 3, 4, and 5 yr follow-up after implantation. Speech perception and speech intelligibility were assessed using hierarchical rating scales. Spearman rank correlation coefficients were used to determine the statistical correlations. All patients were either congenitally deaf or deafened before the age of 3 yr and were implanted before age 7 yr. The patients all received the Nucleus multichannel cochlear implant system with the most appropriate speech encoding strategy.

RESULTS

Speech intelligibility at 5 yr was strongly correlated with speech perception at the 2, 3, 4, and 5 yr intervals after implantation (Spearman coefficients 0.77, 0.81, 0.58, 0.58; p < or = 0.01). Speech intelligibility at the 2, 3, and 4 yr intervals also correlated in a similar manner with earlier speech perception abilities (p < or = 0.01).

CONCLUSIONS

The results suggest that speech intelligibility between 2 and 5 yr after implantation in young children with congenital and prelingual profound deafness can be predicted by measures of earlier speech perception.

Integrity of the auditory pathway in young children with congenital and postmeningitic deafness

This study compares the functional integrity of the auditory pathways of congenitally deaf and postmeningitically deaf children. We used the electrical auditory brain stem response evoked by promontory stimulation to assess 49 profoundly deaf children before cochlear implantation. The age at implantation ranged from 21 months to 15 years (mean 4.5 years). The onset of deafness was either congenital or up to the age of 2 years (mean 5 months). The cause of deafness was meningitis in 19 children (39%) and congenital in 30 (61%). The number of children with identifiable waveform components (eV, eIII, and eII) was significantly greater in the congenitally deaf group. We also analyzed the amplitudes, the latencies, and 4 parameters of the amplitude input-output functions. All the statistically significant differences were in favor of better responses in the congenitally deaf children. These results suggest that the functional status of the peripheral neurons of the auditory pathways may be more intact in congenitally deaf children than in postmeningitic children.

Age at implantation: its importance in pediatric cochlear implantation

OBJECTIVE

To assess the influence of age at implantation on speech perception and speech intelligibility following pediatric cochlear implantation.

STUDY DESIGN

A prospective study was undertaken on a consecutive group of 126 congenital and prelingually deaf children up to 4 years after implantation. The study group was confined to prelingually deaf children less than 7 years of age at the time of implantation. All had implantation with the same multichannel cochlear implant system. No child was lost to follow-up, and there were no exclusions from the study.

METHODS

The Iowa Matrix Closed Set Sentence test, connected discourse tracking, categories of auditory performance, and speech intelligibility rating were used to assess the speech perception (closed and open set) and speech intelligibility of the children with implants. Regression analysis and Spearman rank correlation coefficients were used to assess the correlation between the outcome measures with age at implantation. The setting was a tertiary referral pediatric cochlear implant center in the United Kingdom.

RESULTS

Age at implantation positively correlated with preimplantation assessment performance and with most of the outcome measures up to 24 months following implantation. However, at the 3-and 4-year intervals following implantation, age at implantation was found to be a strong negative predictor of all the outcomes studied (correlation coefficients ranging from -0.44 to -0.58, all statistically significant [P<.05]).

CONCLUSIONS

The results of the present study provide strong evidence that prelingually deaf children should receive implants as early as possible to facilitate the later development of speech perception skills and speech intelligibility and thus maximize the health gain from the intervention. However, because of the wide variation in individual outcomes, age alone should not be used as a criterion to decide implant candidacy.

Speech perception in children after cochlear implantation

OBJECTIVE

This study aimed to determine the speech perception ability of congenitally and prelingually deaf children after cochlear implantation.

STUDY DESIGN

A prospective study was undertaken on a consecutive group of 119 congenitally and prelingually deaf children up to 5 years after implantation. The study group was confined to children between 2 and 7 years of age at the time of implantation. All were implanted with multichannel cochlear implant systems. No child was lost to follow-up, and there were no exclusions from the study other than one child with auditory nerve aplasia.

METHODS

The Iowa Matrix Closed Set Sentence Test and Connected Discourse Tracking were used to assess closed- and open-set speech perception, respectively, without lip reading.

SETTING

The study was conducted at a tertiary referral pediatric cochlear implant center in the United Kingdom.

RESULTS

It was possible to formally test closed-set speech discrimination on 83, 55, 32, 21, and 15 children at 12, 24, 36, 48, and 60 months, respectively. On the Iowa Matrix Test, the median score was 0% at 12 months, reaching a plateau of 99% at 36 months. On Connected Discourse Tracking, the median scores at 12, 24, 36, 48, and 60 months were 0, 0, 21, 40, and 53 words per minute, respectively.

CONCLUSION

Congenitally and prelingually deaf children who receive cochlear implants before the age of 7 years have significant closed-set speech perception abilities develop in <3 years after implantation. Their ability to perform open-set tasks without lip reading is limited in the first 2 years but shows significant improvement, not reaching a plateau, at the 4-5-year interval after implantation.

Is there a correlation between vascular loops and unilateral auditory symptoms?

OBJECTIVES

To assess whether contact of a vascular loop formed by the anterior inferior cerebellar artery (AICA) with the eighth cranial nerve correlated with unilateral auditory symptoms so as to produce a "vascular compression syndrome."

STUDY DESIGN

Prospective evaluation of patients with unilateral auditory symptoms using magnetic resonance imaging (MRI) scans to identify contact of a vascular loop with the eighth cranial nerve.

METHODS

One hundred twelve patients with idiopathic unilateral auditory symptoms (42 women and 70 men, mean age of 51 years) were evaluated with MRI. Location of the vascular loop and contact with the eighth cranial nerve were assessed in each case. The asymptomatic contralateral ears of the patients were used as controls. A power analysis had determined the size of the sample to be studied.

RESULTS

The arterial loop was found to be in contact with the eighth cranial nerve in 28 (25%) of the 112 symptomatic ears and in 24 (21.4%) of the asymptomatic (control) ears. The statistical analysis revealed that the difference was not statistically significant.

CONCLUSION

The results suggest that radiologic demonstration of contact between a vascular loop formed by the AICA and the eighth cranial nerve on MRI scans should be considered a normal anatomic finding and should not, on its own, be used to support the diagnosis of a "vascular compression syndrome."

Speech intelligibility in children after cochlear implantation

OBJECTIVE

This study aimed to evaluate the long-term speech intelligibility of young deaf children after cochlear implantation.

STUDY DESIGN

The study design was a prospective study following a large group of consecutively implanted deaf children with up to 5 years' cochlear implant use.

SETTING

The study was conducted at a pediatric tertiary referral center for cochlear implantation.

PATIENTS

All children in the study were congenitally deaf or deafened before 3 years of age. They each received a Nucleus multichannel cochlear implant before the age of 7 years. Eighty-four subjects were evaluated up to 5 years after cochlear implantation.

INTERVENTION

Cochlear implantation followed by an intensive program of local and center-based assessment and rehabilitation was performed.

MAIN OUTCOME MEASURES

A speech intelligibility rating scale evaluated the spontaneous speech of each child before and at yearly intervals for 5 years after implantation.

RESULTS

After cochlear implantation, the difference between the speech intelligibility ratings increased significantly each year for 4 years (Mann-Whitney U-test). For the first 2 years, the average rating remained "prerecognizable words" or "unintelligible speech." It was not until the 3-year interval that the average intelligibility rating became category 3 (intelligible speech if someone concentrates and lip-reads). At the 4-year interval, 85% of children had some intelligible connected speech. This improvement continued, and at the 5-year interval, the median speech intelligibility was category 4 (intelligible speech to a listener with a little experience of deaf speech) and the mode was category 5 (intelligible speech to all listeners).

CONCLUSION

Congenital and prelingually deaf children gradually develop intelligible speech that does not plateau 5 years after implantation.

Educational placement of deaf children following cochlear implantation

This study examined the educational placements, before cochlear implantation, of 121 deaf children, and the educational placements, two years after implantation, of the 48 children who had reached that stage, looking at the influence of age at implantation and duration of deafness on the placement of these children. In addition, it compared the educational placements of those given implants prior to schooling, and those given implants when already in an educational setting. Categories used were pre-school, school for the deaf, unit or resource base within a mainstream school and full-time mainstream provision. Age at implantation and duration of deafness were found to be significant predictors of placement two years after implantation. The duration of deafness of children in schools for the deaf or units was twice that of children in mainstream education. Fifty-three per cent of children who were in pre-school at the time of implantation were in mainstream schools two years after implantation, whereas only 6% of those who were already in educational placements at the time of implantation were in mainstream education. This difference was statistically significant. The results indicate that children who are given implants early, before an educational decision has been made, are more likely to go to mainstream schools than those given implants when already in an educational setting.

Quality of life after acoustic neuroma surgery

OBJECTIVE

To assess how surgery affected the quality of life of patients with acoustic neuromas and to investigate possible predictors of the functional outcome following surgery.

STUDY DESIGN

A questionnaire based on the Glasgow Benefit Inventory was completed by patients randomly selected following acoustic neuroma surgery.

SETTING

Skull base surgery unit of a university teaching hospital (tertiary referral center).

PATIENTS

Fifty-three patients with acoustic tumors (follow-up, 1 to 3 y).

RESULTS

With regard to overall quality of life, nine patients (17.4%) reported that it became better, 28 patients (53.8%) worse, and 15 patients (28.8%) that it remained the same. Four patients (7.8%) became better off financially, 15 patients (29.4%) worse, and 32 (62.8%) remained unchanged. Forty-one patients (78.8%) did not change their occupation, and 11 (21.2%) had to change their occupation, mainly because of the adverse effects of the operation. With regard to the age at operation, older patients were found to have better overall quality of life. Moreover, younger patients had worse postoperative financial status and they were more likely to change their occupation after the operation. The tumor size did not significantly affect the overall postoperative quality, but it did affect the postoperative financial status (patients with larger tumors were more likely to have worse postoperative financial status).

CONCLUSION

Acoustic neuroma surgery has a significant impact on patients' overall quality of life. Surgeons proposing to operate on small tumors should not assume that the impact on patients' life will be necessarily less than that following the removal of larger tumors. All patients, especially in the younger age group, should be prepared and thoroughly informed about the consequences of the operation on their quality of life.

Cochlear implantation in adults and children

Cochlear implants are electronic devices that are introduced surgically into the inner ear and directly stimulate the auditory nerve in response to sound. They are of benefit to profoundly or totally deaf patients who derive no material benefit from optimally fitted hearing aids.

Multichannel cochlear implantation in postmeningitic and congenitally deaf children

OBJECTIVE

To test the view that prelinguistic postmeningitic deaf (PMD) children outperform congenitally deaf children (CD) in the first year following cochlear implantation.

STUDY DESIGN AND PATIENTS

We evaluated 85 children with ages (at implantation) ranging from 1.9 years to 13.5 years (mean age 5.4 years). The Listening Progress scale was used to assess the developing use of audition 3, 6, and 12 months after implantation.

RESULTS

In contrast to previous reports, the PMD children achieved statistically significantly lower scores than CD children.

Preoperative radiologic evaluation in cochlear implantation

AIM OF STUDY

Assess the value of computed tomography (CT) in the evaluation of abnormalities in the cochlea and auditory pathways.

MATERIAL AND METHODS

We used CT to evaluate 108 children before cochlear implantation surgery. Children's ages at implantation ranged from 21 months to 16 years (mean age, 5.4 years). The etiology of deafness was meningitis in 44 children (40.8%), congenital in 51 (47.2%), and other in 13 children (12%).

RESULTS

Eighteen of the 108 (16.6%) children and 34% of the postmeningitic children were found to have at least partial obliteration of the cochlea. Two (2%) children had congenital malformations of the cochlea and 12 children (11.1%) had abnormalities in the brain CT-scan. CT diagnostic values in postmeningitic children regarding cochlear obliteration were accuracy, 75%; sensitivity, 62%; specificity, 82%; positive predictive value, 66.6%; and negative predictive value, 79.3%. In six (20.6%) of postmeningitic children with normal CT-scans, some scala tympani drillout was required.

CONCLUSION

CT-scan is capable neither of predicting with certainty the presence of minor degrees of cochlear obliteration nor of specifically imaging either the auditory nerve or its central connections.

Electric auditory brain stem response in pediatric patients with cochlear implants

OBJECTIVE

To introduce four comprehensive electrical auditory brain stem response (EABR) parameters that objectively measure the input-output function and may be the base of comparison in related studies.

MATERIALS AND METHODS

In 53 children (106 ears), recordings of the EABR evoked by electrical stimulation at the promontory were made at the time of surgery after the child was anesthetized and before cochlear implantation.

RESULTS

Of the 106 ears studied, 81 (76.4%) produced clearly defined responses. These responses were used to develop a package of four comprehensive EABR parameters (slope, maximal slope, relative growth rate, and maximal relative growth rate) that measure objectively the input-output function. The methods of calculation are described in detail.

CONCLUSION

These parameters may help us to refine and make more consistent the subjective EABR evaluation. They will also enable a comparison of the results from different cochlear implant centers and promote the progress of related research.

Laryngeal tuberculosis at the end of the 20th century

Despite the dramatic reduction in the incidence of laryngeal tuberculosis after the 1950s, the topic has now gained new interest due to claims that the disease has changed its clinical pattern. In the past, the typical patient was 20-40 years old with ulcerated laryngeal lesions, perichondritis, and advanced cavitary lung disease. We studied nine cases of laryngeal tuberculosis confirmed by histological examination. The microlaryngoscopy revealed tumour-like lesions and/or chronic non-specific laryngitis. There were no significant ulcerations or signs of perichondritis. The patients' ages ranged from 48.5 years to 69.3 years (mean, 59.4 years). In three of our patients (33 per cent) we did not find any pulmonary involvement, thus suggesting primary laryngeal tuberculosis or haematogenous spread. In conclusion, the numerous physicians who deal with the various laryngeal symptoms and diseases should be aware of the existence of laryngeal tuberculosis and the changing patterns of the disease (at least in the developed countries).

Auditory function in young patients with chronic renal failure

Debate on the relationship between renal insufficiency and hearing loss continues mainly due to the advanced age and the possible accelerated presbycusis of the patients that have been studied in surveys. Hearing acuity was studied in 46 children and adolescents suffering from renal insufficiency. Sensorineural hearing loss (mainly high-frequency) of unknown cause was found in 14 patients (30.4%). Hearing loss was not influenced by the various haematological, biochemical and clinical parameter (type of renal disease, blood pressure, history of ototoxic drugs administration). However, hearing loss seemed to be affected by the method of management of the renal insufficiency (more in the haemodialysis group than in the peritoneal dialysis group). There were no significant changes in audiometric findings before and after haemodialysis.

Effect of subclinical lead intoxication on laryngeal cancer

In this study we investigated the possible relationship of laryngeal cancer and subclinical lead intoxication, using the depression of aminolevulinic acid dehydratase (ALAD) activity in blood as indicator. Twenty-six patients with laryngeal cancer and 53 normal controls met the criteria to enter the study. Blood ALAD activity values in the patients with laryngeal cancer ranged from 27.1 to 75.3 U/l with a mean of 50.79 U/l. The respective values in the control group ranged from 36.2 to 98 U/l with a mean of 59.76 U/l. There was a statistically significant difference between the two means (0.001 < p < 0.01), whereas blood lead concentrations in all patients were within normal limits. These findings support the hypothesis that low level lead intoxication (subclinical blood lead levels), from cars, industries and products, may contribute to the risk of laryngeal cancer. Further investigation is needed to clarify the exact relationship between lead and cancer of the larynx.