Cochlear implant in guinea: results and perspectives

doi:10.15406/joentr.2025.17.00564

Journal of

eISSN: 2379-6359

Otolaryngology-ENT Research

Research Article Volume 17 Issue 2

Cochlear implant in guinea: results and perspectives

Ibrahima Diallo,¹ Mamadou Saliou Keita,¹ Mamadou Mouctar Ramata Diallo,² Alseny Camara,¹ Mamadou Aliou Diallo,³ Ismael Dabo,⁴ Sayon Kourouma,⁴ Raphan Mady Kaba Keita,⁵ Alseny Cissé,⁶ Mamadou Gouraisiou Diallo,¹ Aminata Gadjiko Diallo,⁷ Mohamed Casimir Kaman,¹ Abdoulaye Keita,¹ Alpha Oumar Diallo⁷

¹Department of ENT, Head and Neck Surgery, Donka National Hospital, Guinea
²Department of ENT, Head and Neck Surgery, Mamou Regional Hospital, Guinea
³Department of ENT, Head and Neck Surgery, ENTAG Regional Hospital, Guinea
⁴Department of ENT, Head and Neck Surgery, Conakry Military Hospital, Guinea
⁵Department of ENT, Head and Neck Surgery, N’ZEREKORE Regional Hospital, Guinea
⁶Department of ENT, Head and Neck Surgery, LABE Regional Hospital, Guinea
⁷Department of ENT, Head and Neck Surgery, Ignace Deen National Hospital, Guinea

Correspondence: Dr Ibrahima Diallo, Department of ENT, Head and Neck Surgery, Donka National Hospital, CHU of Conakry, Guinea.

Received: April 22, 2025 | Published: May 14, 2025

Citation: Diallo I, Keita MS, Diallo MMR, et al. Cochlear implant in guinea: results and perspectives. J Otolaryngol ENT Res. 2025;17(2):44‒47. DOI: 10.15406/joentr.2025.17.00564

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Abstract

Introduction: The cochlear implant is a medical device placed in the inner ear through surgery. It is used to correct profound sensorineural hearing loss in patients. Objective: To report the results of the first cohort of cochlear implants in Guinea and present future prospects.

Methodology: This was a descriptive study with retrospective data collection over 6 months (July – December 2024), conducted at the ENT Department of Donka National Hospital.

Results: We recorded 15 cases of cochlear implants performed during three missions in three different countries (8 in Guinea; 5 in Morocco; and 2 in Ivory Cost). The patients included 7 girls and 8 boys. Their average age was 3.13 years. All presented with severe to profound bilateral sensorineural hearing loss, including 11 children with pre-lingual deafness. Cochlear implantation was unilateral in all patients. Device tuning and speech therapy rehabilitation were conducted regularly. Pre- and postoperative therapeutic education was provided to all parents. Results were satisfactory (6-month follow-up), based on speech therapy reports and parental feedback. Factors influencing these satisfactory outcomes included early cochlear implantation, strong parental involvement, and consistent speech therapy follow-up.

Conclusion: The emergence of cochlear implantation in Guinea is the result of support from policymakers and partners. Our major future goal is to establish a cochlear implant center in Guinea.

Keywords: cochlear implant, results, prospects, guinea

Introduction

Cochlear implants are electro-acoustic prostheses that compensate for bilateral inner ear deficiencies, whether profound or severe, acquired or congenital.¹ They convert sound waves into electrical signals that directly stimulate the auditory nerve. Cochlear implantation has now proven effective in rehabilitating hearing loss in both adults and children.²It requires the involvement of a multidisciplinary team with appropriate technical and audiophonological facilities.³

Our objective is to report the results of the first cohort of cochlear implants in Guinea and outline future perspectives.

Methodology

This was a cross-sectional descriptive study with retrospective data collection, conducted in the Department of Otorhinolaryngology and Head and Neck Surgery at Donka National Hospital over a six-month period, during three cochlear implantation missions carried out in three different countries (Guinea, Morocco, and Ivory Cost).

We included all complete records of implanted patients, regardless of age, sex, or surgical site, provided they were all followed up at the ENT and Head and Neck Surgery Department of Donka National Hospital. Incomplete records were excluded. Sampling was exhaustive.

Data collection was based on clinical records, surgical and hospitalization reports, and speech therapy evaluation forms.

Patients were regularly called in for follow-up at 1 month, 2 months, and 3 months post-implantation. The APCEI profile was used to assess speech therapy outcomes. The following parameters were studied: epidemiological, diagnostic, therapeutic, and follow-up outcomes.

Data were entered using Kobocollect software and analyzed with SPSS version 22. The results were used solely for scientific purposes. Medical confidentiality was strictly maintained.

Results

Epidemiology and etiology

We recorded 15 implanted patients, including 11 children with pre-lingual and 4 post-lingual deafness. The average age at pediatric cochlear implantation was 9.13 ± 10.58 years (ranging from 1 year and 6 months to 10 years). Three adults received implants (Table 1). The etiologies of deafness were as follows: severe malaria in 1 case, Usher syndrome in 1 case, post-bacterial meningitis deafness in 7 cases, and congenital origin in the remaining 6 patients.

Age group	Frequency	%
0 – 3 years	3	20
4 – 7 years	8	53.33
8 – 11 years	1	6.67
> 11 years	3	20
Total	15	100

Table 1 Distribution of implanted patients by age group

Medical history	Frequency	%
Meningitis	7	46.66
Otitis	6	40
Usher Syndrome	1	6.67
Cranioencephalic Malformation	1	6.67
Total	15	100

Table 2 Distribution of implanted patients by medical history.

Pre-cochlear implantation assessment (Table 3)

All patients underwent a pre-cochlear implantation assessment, including clinical, audiological, radiological, speech therapy, and psychological evaluations. No contraindications to cochlear implantation were identified during the assessment. A hearing aid trial was conducted in 3 patients. In one case, imaging revealed a complex right-sided unilateral cochlear malformation; the implant was placed on the contralateral side.

Exploration assessment		Frequency	%
Audiométrie comportementale	Yes	3	20
	No	12	80
Speech Therapy Assessment, ASSR, OAE, CT Scan, and MRI	Yes	15	100

Table 3 Distribution of implanted patients according to the completion of additional tests

ASSR, auditory steady-state response; OAE, otoacoustic emission; CT Scan, computed tomography scan

Cochlear implant surgery

The implantation was unilateral in all patients, with 13 cases on the right side and 2 cases on the left side. The surgery was performed with facial nerve monitoring and without incidents. The approach used was the retro-auricular approach with a posterior tympanotomy to expose the round window, and one case of meatomy with two cases of cochleotomy. The electrode array insertion was complete in the tympanic ramp in all patients (Table 4).

Surgical parameters		Frequency	%
Implanted ear	Right ear	13	86,67
	Left ear	2	13,33
Implant model	COCHLEAR	7	46,67
	ME-DEL	8	53,33
Intra-operative	Retro-auricular approach + posterior tympanotomy	14	93,33
	Meatomy + cochleotomy	1	6,67
Post-operative	Complete device placement	15	100

Table 4 Distribution of implanted patients according to side and type of implants used

Post-surgery complications		Frequency	%
Postoperative Outcomes	No complications	15	100
Cochlear Implant Activation	1 month after implant placement	15	100
Post-Surgery Audiometric Assessment	Good	15	100
Stenvers Radiography	Good	15	100
Post-Activation Speech Therapy Assessment	Good	15	100

Table 5 Distribution of implanted patients according to postoperative outcomes

Post-cochlear implantation follow-up

The average duration of hospitalization was 48 hours. Sternvers radiography confirmed the correct placement of the cochlear implant in all patients (Figure 3). Postoperative recovery was uncomplicated. The first adjustment or activation of the cochlear implant was performed one month after surgery (Figures 1 & 2). Speech therapy rehabilitation was regular, with an average of 2 sessions per week. The settings were regularly adjusted and modified thereafter according to the progress in speech therapy rehabilitation (at 1, 2, or 3 months).

Figure 1 Child wearing a Cochlear processor.

Figure 2 Child wearing a MEDEL processor.

Figure 3 Sternvers radiograph showing correct placement of the cochlear implant.

Evaluation of speech therapy results after cochlear implantation

The speech therapy evaluation using the APCEI questionnaire was conducted both before cochlear implantation and during follow-up. All patients had a score of 0 before cochlear implantation in all areas of the questionnaire used. The results showed significant inter-individual variability (age of implantation, duration of implant use, motivation, and rate of speech therapy rehabilitation). It was observed that good results were correlated with early implantation and, therefore, a shorter duration of auditory deprivation. Children with strong parental involvement and good follow-up in speech therapy rehabilitation achieved the best results compared to those with weak or moderate follow-up.

Discussion

We encountered virtually no difficulties that would hinder the scientific quality of this series. Indeed, it was compiled from 15 cases of cochlear implants for profound, bilateral, disabling sensorineural deafness. Hearing loss is the most common sensory deficit, with a prevalence of 1/1000 births and 5/1000 adults ^4–6; severe and profound hearing loss is responsible for major social and psychological handicaps, especially in children before language development.⁷ Rehabilitation of this hearing loss with cochlear implants bypasses damaged or absent hair cells to directly stimulate the auditory nerve.⁸ All our patients underwent the pre-implantation evaluation, including ABR, ASSR, CT scan, MRI, and speech therapy assessment, where we did not find any contraindications, specifically cochlear malformations.⁹

The indications for cochlear implantation are widely described in the report of the Hight Authority for Health (HAS).¹⁰ The cochlear implantation should be as early as possible in cases of pre-lingual deafness (before 2 years old), and there is no age limit for post-lingual deafness (after 5 years old) and in adults.⁷ We selected patients who were potentially suitable for implantation, informed them about the surgery, settings, rehabilitation, and follow-up, which was conducted by an experienced multidisciplinary team.¹¹ This team consists of speech therapists, surgeons, anesthetists, electrophysiologists, radiologists, psychologists, and audiologists.¹²

The surgery involved a retro-auricular incision, with the receiver fixed in the retro-mastoid region, a posterior tympanotomy to expose the round window, and the insertion of the electrode array into the tympanic ramp to reproduce the natural frequency tonotopy of the ear. Post-implantation audiometry showed the proper placement and functionality of all electrodes.¹³ In our study, we did not observe any post-cochlear implantation complications in the 15 patients, which may explain the good postoperative progress. Another study reports post-implantation complications.¹⁴

The follow-up of implanted patients after surgery is key to the success of any cochlear implantation. The activation of the electrodes was performed one month after wound healing, with frequent adjustments in the months following implantation, then spaced according to the patient's perception evolution.¹⁵Speech therapy rehabilitation must be regular and long-term, especially for all patients following the APCEI profile used in our evaluation. It remains a simple, quick test to perform and explores various domains of speech therapy assessment (auditory perceptions, comprehension of the perceived oral message, oral expression, and speech intelligibility).¹⁶

Cochlear implantation is a safe, effective technique when targeted at correctly selected populations. Its effectiveness has already been demonstrated, and our results align with those of the literature.¹⁷Literature data confirm that good results are mainly correlated with early implantation, strong parental involvement, and good follow-up of speech therapy rehabilitation and adjustments. Knowledge of all the factors (age of implantation, duration of auditory deprivation, speech therapy rehabilitation, motivation, comorbidity) helps to tailor patient follow-up on a case-by-case basis to further improve cochlear implantation outcomes.¹⁸

Conclusion

Cochlear implantation is a powerful tool for rehabilitating severe to profound deafness. It is a safe and effective technique when directed at appropriately selected populations and supported by a multidisciplinary approach. The earlier the cochlear implantation and the greater the parental involvement, the more satisfactory the results.

Perspectives

The implementation of a hearing screening program in neonatal settings and the creation of cochlear implantation centers in our countries would help facilitate early diagnosis and the consideration of cochlear implantation, promoting a positive outcome.