Age‐dependent variations of scalp thickness in the area designated for a cochlear implant receiver stimulator

Abstract

ObjectiveThe integrity of the scalp overlying a cochlear implant receiver stimulator (RS) is critical for the long‐term survival of the implant. Exposure or extrusion of the device will likely result in the need for its removal. There is a global trend of acceleration of population aging, thus raising the prevalence of cochlear implantation (CI) in the elderly. The aim of this study was to define age‐dependent changes in scalp thickness and discuss the implication of that anatomical characteristic for CI in the geriatric population.MethodsScalp thickness over the location of the RS in the temporo‐parietal area was measured directly with a needle in patients of various ages.ResultsTwo‐hundred thirty‐six temporo‐parietal scalps were measured in patients aged 18 to 85 years. A strong inverse correlation was found between age and scalp thickness (rs = ‐0.723, P < .001). Scalp thickness decreased with age from a mean of 8 mm in the third decade of life to 5 mm in the ninth decade of life.ConclusionThe human scalp thins with age and most likely undergoes a reduction in its strength. As a consequence, implantable hearing devices that are shielded by the scalp can be at increased risk of exposure and extrusion in the aging recipient. This needs to be taken into account when considering an implantation procedure, the surgical approach and patient instructions on need for and venues for continuing care over time.Level of Evidence2B

Preoperative Imaging of Temporoparietal Scalp Thickness Predicts Off-the-Ear Sound Processor Retention in Cochlear Implants With Diametric Magnets

“…In the present study, there was no correlation between age and skin flap thickness ( p ¼ 0.14, r ¼ -0.12). This differs from Ungar et al (9) who did find a significant negative correlation between age and skin flap thickness. Their study measured skin flap thickness directly using a needle; however, which is distinct from our study which measured skin flap thickness radiographically.…”

Hearing Outcomes and Complications of Cochlear Implantation in Elderly Patients over 75 Years of Age

“…Therefore, rehabilitation for equilibrium function should be started as soon as possible after surgery in elderly patients who complain of dizziness or vertigo. In addition, skin inflammation around the RS is more likely to occur in elderly patients because of age-related thinning of the skin on the scalp [ 22 ]. Inflammation of the scalp may cause necrosis at this site, which prevents patients from using their CI.…”

“…However, it is difficult for elderly patients to notice this themselves. Therefore, family members and medical staff should be instructed to monitor the patient’s surgical site carefully [ 22 , 23 ]. If redness or pain occurs on the skin around the RS site, the magnet’s strength should be changed as soon as possible to prevent skin damage.…”

A novel treatment for CI extrusion with vacuum-assisted closure device

“…Our patient had presented with a soft tissue infection with flap breakdown 18 years after her cochlear implantation. In a study by Ungar et al (2018) in 2018 where 236 temporo-parietal scalps were measured in patients aged 18-85 years, scalp thickness decreased with age from a mean of 8 mm in the third decade to 5 mm in the ninth decade. As the skin ages, the subcutaneous layer atrophies as skin appendages become more scarce, blood flow decreases and there is degeneration of the extracellular matrix accompanied by fewer fibroblasts and altered collagen (Makrantonaki and Zouboulis, 2007).…”