Christopher Raine

Cochlear implantation in Jervell and Lange-Nielsen syndrome

A case of familial prolonged QT interval and congenital sensorineural hearing loss is described emphasising the diagnostic and management implications. Jervell and Lange-Nielsen syndrome is important because of its potential association with sudden death in children with congenital sensorineural deafness. It is known to be associated with mutations of the genes KCNQ1 (KVQTI) and KCNE1 (Isk). The underlying molecular abnormality leads to cardiac and cochlear dysfunction through a potassium channel defect. All children with congenital sensorineural hearing loss who have suffered unexplained syncopal attacks or convulsions should be screened for this syndrome. There is also a strong case for including a 12 lead ECG as part of the investigative work up of all children with congenital sensorineural deafness in whom a firm aetiology has not been established.

How we do it: using a surgical navigation system in the management of the ossified cochlea.

Abstract The ossified cochlea poses both concerns and challenges to any implant team. One of the surgical aims is to implant as many of an implant systems electrodes into the cochlea as close to the modiolus as possible, thus facilitating stimulation of the surviving cell bodies in the spiral ganglion. Within the field of otorhinolaryngology various surgical navigation systems have been introduced to facilitate surgical orientation during endoscopic sinus and skull-base surgery. The principle behind such systems is that specialized software uses high-resolution computerized tomography and magnetic resonance imaging scans to create a 3D image of the patients anatomy. This ‘virtual patient model’ is then ‘registered’ with the patients anatomical landmarks. Surgical instruments registered into, or linked with, the system can then be tracked within the 3D model. This is the first time this system has been described for surgery of the inner ear, and we describe how the technique allows more precise control of the bur tip while drilling tunnels that approximate with the apical and distal parts of the basal coil of the ossified cochlea.

Skin flap thickness in cochlear implant patients — a prospective study

Abstract The thickness and quality of the skin overlying a cochlear implant is important for its integrity. It should be thick enough to protect the implant and prevent flap breakdown yet should not be so thick that it impedes the electronic signal or causes difficulty wearing the coil because of loss of the magnetic coupling. The principle of this study was to devise a method to assess the thickness of skin over a cochlear implant receiver stimulator package and prospectively measure this thickness during the first year following surgery. All patients studied were implanted with MED-EL COMBI 40+ implants. The first cohort consisted of 35 adults; the second 23 children. Various methods of measurement were assessed. In this study the principle of the Hall Effect electrode was used to measure the magnetic flux density of the magnet within the receiver stimulator package. Following standardization, results showed that skin thickness significantly thinned in the adult group before stabilizing. This was less obvious in children, probably due to the effect of the skin thickening as the child grows. Knowledge of skin thickness has implications relating to the functioning of an implant and avoiding potential flap related complications. Copyright

An open safety pin in the larynx: a case report

Inhalation of a foreign body is a serious event. The number of foreign bodies that become impacted in the larynx is small and requires urgent recognition. We describe the case of a six-month-old baby with an impacted open safety pin in the larynx. The sharp end of the safety pin was upwards and had penetrated the anterior end of the left vocal fold. We discuss the management and describe our method of removal of the foreign body. Tracheostomy was not required in this case and the child had an uneventful recovery. A brief review of the literature is included.

Cochlear implantation — United Kingdom and Ireland surgical survey

Cochlear implantation has now become a routine procedure in the management of severe to profound deafness. An initial survey was carried out in late 1997 of the surgeons carrying out implantation in the United Kingdom and Ireland, requesting details of medical and surgical aspects of cochlear implantation. A follow-up survey was conducted in early 2002 to evaluate any changes in clinical practice. The reported results show a low surgical complication rate in both children and adults. Reasons for this are discussed.

The effect of early auditory experience on the spatial listening skills of children with bilateral cochlear implants

OBJECTIVES Both electrophysiological and behavioural studies suggest that auditory deprivation during the first months and years of life can impair listening skills. Electrophysiological studies indicate that 3½ years may be a critical age for the development of symmetrical cortical responses in children using bilateral cochlear implants. This study aimed to examine the effect of auditory experience during the first 3½ years of life on the behavioural spatial listening abilities of children using bilateral cochlear implants, with reference to normally hearing children. Data collected during research and routine clinical testing were pooled to compare the listening skills of children with bilateral cochlear implants and different periods of auditory deprivation. METHODS Children aged 4-17 years with bilateral cochlear implants were classified into three groups. Children born profoundly deaf were in the congenital early bilateral group (received bilateral cochlear implants aged ≤3½ years, n=28) or congenital late bilateral group (received first implant aged ≤3½ years and second aged >3½ years, n=38). Children with some bilateral acoustic hearing until the age of 3½ years, who subsequently became profoundly deaf and received bilateral cochlear implants, were in the acquired/progressive group (n=16). There were 32 children in the normally hearing group. Children completed tests of sound-source localization and spatial release from masking (a measure of the ability to use both ears to understand speech in noise). RESULTS The acquired/progressive group localized more accurately than both groups of congenitally deaf children (p<0.05). All three groups of children with cochlear implants showed similar spatial release from masking. The normally hearing group localized more accurately than all groups with bilateral cochlear implants and displayed more spatial release from masking than the congenitally deaf groups on average (p<0.05). CONCLUSION Children with bilateral cochlear implants and early experience of acoustic hearing showed more accurate localization skills, on average, than children born profoundly deaf.

Quality standards for bone conduction implants

Abstract Conclusion: Bone conduction implants are useful in patients with conductive and mixed hearing loss for whom conventional surgery or hearing aids are no longer an option. They may also be used in patients affected by single-sided deafness. Objectives: To establish a consensus on the quality standards required for centers willing to create a bone conduction implant program. Method: To ensure a consistently high level of service and to provide patients with the best possible solution the members of the HEARRING network have established a set of quality standards for bone conduction implants. These standards constitute a realistic minimum attainable by all implant clinics and should be employed alongside current best practice guidelines. Results: Fifteen items are thoroughly analyzed. They include team structure, accommodation and clinical facilities, selection criteria, evaluation process, complete preoperative and surgical information, postoperative fitting and assessment, follow-up, device failure, clinical management, transfer of care and patient complaints.

Hearing preservation cochlear implantation in children: The HEARRING Group consensus and practice guide

Objectives: To provide multidisciplinary cochlear implant teams with a current consensus statement to support hearing preservation cochlear implantation (HPCI) in children, including those children with symptomatic partial deafness (PD) where the intention is to use electric-acoustic stimulation (EAS). The main objectives are to provide guidelines on who is a candidate, how to assess these children and when to implant if Med-El Flex electrode arrays are chosen for implantation. Methods: The HEARRING group reviewed the current evidence and practice regarding the management of children to be considered for HPCI surgery emphasizing the assessment needed prior to implantation in order to demonstrate the benefits in these children over time. The consensus statement addresses following three key questions: (1) Should these children be treated? (2) How to identify these children? (3) How to manage these children? Summary: The HEARRING group concludes that irrespective of the degree of residual hearing present, the concepts of hearing and structure preservation should be applied in every child undergoing cochlear implantation and that HPCI is a safe and reliable treatment option. Early detection and multidisciplinary assessment are key to the identification of children with symptomatic PD, these children should undergo HPCI as early as possible.

Cochlear implantation in Refsum's disease.

Abstract Refsums disease is a rare disorder characterized by accumulation of phytanic acid in plasma and tissues. The main clinical features are retinitis pigmentosa, cerebellar ataxia and chronic polyneuropathy. Sensorineural hearing loss of varying severity can be an additional feature. This study reports our experience with two patients with Refsums disease who underwent successful cochlear implantation. Both patients had good audiological outcomes after implantation and were overall very satisfied. Bilateral implantation should be considered with patients with severe dual sensory loss. One patient was implanted bilaterally the other unilaterally, primarily due to prolonged duration of unaided unilateral profound hearing loss. Copyright

The Bradford bone-anchored hearing aid programme: impact of the multidisciplinary team

OBJECTIVES The aim of this study was to assess the impact on implant survival, abutment skin reaction and patient satisfaction in patients implanted with a bone-anchored hearing aid (BAHA), following the introduction of a multidisciplinary team (MDT) in 1997. DESIGN AND METHODS Part prospective and retrospective analysis. Implant survival and cause of failures were recorded along with abutment skin reaction (graded as none, mild, moderate and severe, according to the amount of wound care required). Patient satisfaction and quality of life were assessed using a questionnaire enquiring about several aspects of the use and benefits of their BAHA. SETTING AND PARTICIPANTS Eighty patients treated at the Bradford Royal Infirmary between 1991 and 2005. The unit is a recognized tertiary referral centre. RESULTS AND CONCLUSIONS Twelve out of 80 implants failed, giving an overall failure rate of 15 per cent. Kaplan-Meier survival curves show a steady decrease in implant survival. The MDT had a positive effect on implant survival and adverse skin reactions, with a higher proportion of patients experiencing no reaction after its introduction. There was a 92.5 per cent response rate to the questionnaire. Overall patient satisfaction was high, both before and after the introduction of the MDT.