Long-Term Outcomes of Cochlear Implantation in Irradiated Ears of Nasopharyngeal Carcinoma Patients

Cochlear implantation after head and neck radiotherapy: A multicentric study and systematic review

OBJECTIVE

The objective of this study is to assess whether cochlear implantation is feasible in patients treated with radiotherapy of the temporal bone (for diseased other than vestibular schwannoma), in terms of surgical management and auditory outcome.

METHODS

A systematic review of the literature was performed, screening PubMed, Embase, and Scopus databases, according to PRISMA criteria, retrieving 12 articles. Moreover, 9 cases coming from a multicentric study involving Padova and Pisa University Hospitals, were added, for a total of 62 cases of irradiated patients receiving cochlear implantation.

RESULTS

In our multicentric study we included a total of 9 patients, 6 males, and 3 females (mean age at first cochlear implantation was 53.89 years ± 21.07), while from the literature we considered 53 cases (mean age at first cochlear implantation 48.78 years ± 12.41). We considered for both groups a set of preoperative imaging abnormalities, intraoperative complications and possible postoperative complications. In our cohort, the preoperative pure tone average (PTA) in the implanted ear was 105.6 dB, and the postoperative one was 34.6 dB. In the literature the preoperative PTA was 111.5 dB (when reported), and the postoperative one 52.8 dB.

CONCLUSION

Both our experience and the literature suggest that cochlear implantation in an irradiated ear is feasible with a good auditory outcome. Surgical difficulties and fitting challenges can be easily managed by professionals aware of these findings, making these patients good candidates to this rehabilitative option.

Neurological complications of modern radiotherapy for head and neck cancer

Radiotherapy is one of the mainstay treatment modalities for the management of non-metastatic head and neck cancer (HNC). Notable improvements in treatment outcomes have been observed in the recent decades. Modern radiotherapy techniques, such as intensity-modulated radiotherapy and charged particle therapy, have significantly improved tumor target conformity and enabled better preservation of normal structures. However, because of the intricate anatomy of the head and neck region, multiple critical neurological structures such as the brain, brainstem, spinal cord, cranial nerves, nerve plexuses, autonomic pathways, brain vasculature, and neurosensory organs, are variably irradiated during treatment, particularly when tumor targets are in close proximity. Consequently, a diverse spectrum of late neurological sequelae may manifest in HNC survivors. These neurological complications commonly result in irreversible symptoms, impair patients' quality of life, and contribute to a substantial proportion of non-cancer deaths. Although the relationship between radiation dose and toxicity has not been fully elucidated for all complications, appropriate application of dosimetric constraints during radiotherapy planning may reduce their incidence. Vigilant surveillance during the course of survivorship also enables early detection and intervention. This article endeavors to provide a comprehensive review of the various neurological complications of modern radiotherapy for HNC, summarize the current incidence data, discuss methods to minimize their risks during radiotherapy planning, and highlight potential strategies for managing these debilitating toxicities.

Cochlear Implantation After Head and Neck Radiation: A Case Series, Systematic Review, and Meta-analysis

OBJECTIVE

To determine if cochlear implant (CI) is safe and effective in patients with radiation therapy (XRT)-induced sensorineural hearing loss and to discuss considerations in this population through a retrospective cohort review, systematic review, and meta-analysis.

DATABASES REVIEWED

PubMed, Cochrane Library, and Embase.

METHODS

We retrospectively reviewed all CI cases after head and neck (HN) XRT at our institution, noting intraoperative findings, postoperative complications, and hearing outcomes. Change in speech discrimination scores (SDSs) was the primary outcome measure. Systematic review was performed to identify all cases of CI after HNXRT. A meta-analysis was performed to assess SDS change.

RESULTS

The retrospective cohort review identified 12 patients who underwent CI after HNXRT. One patient with HN cancer (HNC) and one with central nervous system pathology (CNSP) received bilateral implants. Six had HNC, three had CNSP, and one had Langerhans cell histiocytosis. Eleven had abnormal findings during CI. There were no postoperative complications. Twenty articles with an additional 97 patients were suitable for systematic review inclusion. Of the 109 patients, 67 (61.5%) had HNC and 18 (16.5%) had CNSP. Abnormal intraoperative findings were common (30.3%), most frequently in the mastoid (66.7%). Postoperative complications, including wound dehiscence and infection with some requiring explantation, occurred in 10.1% of patients. Sixty-six patients were included in the meta-analysis. All demonstrated SDS improvement (mean increase, 56.2%).

CONCLUSION

Patients with prior HNXRT benefit from CI. Paying careful attention to surgical planning and technique, postoperative care, and patient expectations is imperative, as complications are not uncommon.

Cochlear Implantation in Radiation-Induced Hearing Loss: A Systematic Review

OBJECTIVE

Cochlear implantation (CI) has been reported as a treatment modality for radiation-induced sensorineural hearing loss (SNHL). However, its efficacy is based on individual reports with no cumulative supporting evidence. Therefore, we conducted the current systematic review to provide cumulative evidence regarding the feasibility and safety of CI in this context.

DATABASES REVIEWED

An online bibliographic search was conducted in PubMed, ProQuest, Scopus, Google Scholar, and Web of Science using MeSH-based terms.

METHODS

A systematic review was conducted to retrieve both observational and interventional studies that reported the outcomes of CI for patients suffering from radiation-induced SNHL.

RESULTS

We included 12 studies that recruited 88 patients who underwent CI because of radiation-induced SNHL. All included studies reported satisfactory hearing/speech perception outcomes. No serious complications were reported, whereas some manageable adverse events were reported, such as paroxysmal facial spams (n = 1), postauricular wound dehiscence with mastoid cutaneous fistula (n = 1), dehiscence in blind sac closure (n = 1), and electrode exposure (n = 1). Four studies assessed the postoperative quality of life/patient satisfaction, showing improved outcomes.

CONCLUSION

CI could be considered to be feasible and safe in patients with irradiation-induced SNHL. The adverse events of CI in such cases are manageable. Future studies are needed to be strengthened this context.

Effects of Age on Delayed Facial Palsy After Otologic Surgery: A Systematic Review and Meta-Analysis

OBJECTIVES

To report 4 cases of delayed facial palsy (DFP) after pediatric middle ear (ME) surgery and systematically review and analyze the associated literature to evaluate the effects of age on DFP etiology, management, and prognosis.

METHODS

Systematic review of PubMed, Cochrane Library, and Embase for articles related to DFP after cochlear implantation (CI) was performed. These articles were assessed for level of evidence, methodological limitations, and number of cases. Meta-analysis was performed to assess the effects of age on DFP incidence. Furthermore, a comprehensive list of all pediatric DFP cases after otologic surgery was assembled through a multi-institutional retrospective review and systematic review of the literature.

RESULTS

Twenty-nine articles fit the criteria for inclusion in the meta-analysis. The incidence of DFP after CI was 0.23% and 1.01% for pediatric and adult cases, respectively. This difference was statistically significant (P < .001, odds ratio 4.36). Twenty-three cases, adding to the 4 presented herein, were suitable for a comprehensive list. The mean age was 6.9 years. Average postoperative day of paresis onset was 5.4, with an average maximum House-Brackmann grade of 3.5. All patients obtained full facial recovery after an average of 23.5 days.

CONCLUSIONS

The systematic review demonstrates that DFP after pediatric CI is rare and occurs at a significantly lower rate than in adults, further supporting the viral reactivation hypothesis of DFP. The prognosis for pediatric DFP after otologic surgery is excellent, with a high rate of full recovery in a short time frame. However, steroid administration can be considered.

LEVEL OF EVIDENCE

IIa.

Cochlear Implantation Outcomes in Patients With Retrocochlear Pathology: A Systematic Review and Pooled Analysis

OBJECTIVE

To review the current literature regarding cochlear implantation in patients with retrocochlear pathologies and extract speech perception scores between 6 months and 1 year after surgery.

DATABASES REVIEWED

PubMed/MEDLINE, Embase and Cochrane CENTRAL via Ovid, CINAHL Complete via Ebsco, and Web of Science.

METHODS

The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Search strategies included keywords and subject headings to maximize retrieval and reflect cochlear implants and retrocochlear pathologies. Patients with previously resected vestibular schwannoma (VS) were excluded.

RESULTS

There were 2,524 abstracts screened against inclusion criteria, and 53 studies were included, with individual data available for 171 adult patients. Pathologies included were either observed or irradiated VS (previously operated tumors were excluded) (n = 99, 57.9%), superficial siderosis (n = 39, 22.8%), neurosarcoidosis (n = 11, 6.4%), and previous central nervous system or skull base radiation (n = 22, 12.9%). Mean (standard deviation) postoperative consonant-nucleus-consonant (CNC) word scores were 45.4% (24.2) for observed VS, 44.4% (20.8) for irradiated VS, 43.6% (21.0) for superficial siderosis, 89.5% (3.0) for neurosarcoidosis, and 30.0% (30.2) in patients with previous central nervous system or skull base irradiation. Irradiated compared with observed VS had similar postoperative CNC word scores (effect size, 0.06; p = 0.71). Age, sex, maximal tumor dimension, and neurofibromatosis type 2 status did not significantly impact cochlear implant performance in patients with VS. Eighty-two percent of patients with reported device usage were daily users, and overall, 82% of cases benefitted from cochlear implantation.

CONCLUSION

Cochlear implantation in patients with concomitant retrocochlear pathology generally results in improved speech discrimination scores sustained over time.