Disertasi

Posisi Elektroda Intrakoklea dan electrically evoked compound action potential sebagai pedoman pemetaan: Kajian pada anak tuli sensorineural kongenital dengan implan koklea. = The location of intracochlea electrode and electrically evoked compound action potential as a guidance for mapping: A study in children with congenital sensorineural hearing loss using cochlear implant.

Pendahuluan. Implan koklea merupakan pilihan utama untuk habilitasi pendengaran dan berbicara pada anak tuli sensorineural berat bilateral •. Untuk mencapai hasil maksimal dibutuhkan seleksi kandidat, prosedur operasi dan habilitasi. Pengaturan comfortable dan threshold level berdasarkan nilai evoked compound action potential (ECAP) direkam dengan neural responses imaging (NRI) pada pemetaan. Tujuan. Memperoleh nilai ECAP sebagai acuan pemetaan berdasarkan jarak elektroda intrakoklea ke modiolus, jarak terpanjang elektroda nomor satu dengan elektroda berhadapan, jarak marker dengan lubang kokleostomi dan faktor lainnya. Bahan dan cara kerja. Anak tuli sensorineural usia 7-10 tahun, menggunakan implan koklea dengan desain contour atau straight terdiri dari 16 elektroda, 120 channel sebagai subjek penelitian. Pemilihan subjek penelitian sebanyak 46 telinga yang terpasang implan koklea dari 39 anak yang memenuhi kriteria penerimaan diperoleh secara konsekutif dengan desain potong lintang. Setelah mendapatkan informed consent, kuesioner diisi oleh orang tua. Perekaman ECAP pada elektroda 3-5, 8-10, 13-15 mewakili daerah apeks, medial dan basal. Hasil tomografi komputer resolusi tinggi koklea dengan program OsiriX dilakukan rekonstruksi 3D menilai po sisi dan jarak elektroda. Analisis data diawali dengan deskripsi subjek penelitian, uji korelasi Spearman 's antara ECAP dengan faktor yang dinilai. Kandidat faktor yang berperan berdasarkan uji korelasi disertakan pada regresi ganda untuk mendapatkan faktor determinan ECAP. Comfortable zone untuk populasi diperoleh dari analisis area pada distribusi normal menggunakan comfortable level. Hasil penelitian. Faktor yang berperan pada ECAP adalah jarak elektroda ke modiolus, lama pemakaian implan koklea dan threshold level. Persamaan yang diperoleh y (ECAP rerata) = -21,19 + 5,87 jarak elektroda rerata ke modiolus (mm) + 1,31, threshold level rerata (cu) + 0,48 lama pemakaian implan koklea rerata (bulan). (R square = 0,60). Comfortable zone diperoleh dengan ECAP yang berada pada variasi 84-87,5% comfortable level. Simpulan. Diperolehnya jarak elektroda ke modiolus, lama pemakaian implan koklea dan threshold level sebagai faktor determinan terhadap ECAP. Nilai ECAP dapat digunakan sebagai acuan identifikasi penyimpangan jarak elektroda dan memperoleh comfortable zone.
Kata kunci : ECAP, implan koklea, posisi elektroda, tuli sensorineural.



Introduction. Cochlear implant is currently considered as a preferred choice in hearing and speech habilitation in children with bilateral profound sensorineural hearing loss. Candidate selection, surgical procedure and habilitation were needed to achieve maximal outcome. Comfortable and threshold level setting based on evoked compound action potential (ECAP) value is recorded by neural responses imaging (NRI) during mapping. Objectives. To obtain ECAP value as mapping guidance based on the distance between intra-cochlea electrode to modiolus, the longest distance between electrode number one with the one it faces, the distance between marker and cochleostomi and other factors Materials and methods. Research subject are children with SNHL between 2-10 years old using contour or straight cochlear implant with 16 electrodes and 120 channels. The research found 46 ears with cochlear implant from 39 children who met the criteria chosen consecutively by cross sectional design. The parents give informed consent and filled the questionare. Using NRI, ECAP was recorded on electrode 3-5, 8-10, 13-15 that represent the apex, medial and basal area. Their cochlear was examined with high-resolution computed tomography (HRCT) then 3D reconstruction with OsiriX program was done to determine the electrode position and calculate distance between the electrode and modiolus. Data analysis starts with research subject description and analysed with Spearman' correlation test between ECAP and a number of factors. Candidate's factor role based on correlation test is also analysed with multiregression test to gain ECAP determinant factor. Comfortable zone for population is gained from area analysis in normal distribution using comfortable level. Results. The role factors in ECAP are electrode modiolus distance, cochlear implants duration use and Threshold level. The equation found was: y (average ECAP) = -21.19 + 5.87 the average electrodes to modiolus distance (mm) + 1.31, average threshold level (cu) + 0.48 cochlear implant average length use (months). (R square = 0.60). Comfortable zone is acquired with ECAP which value between 84-87.5% comfortable level variation. Conclusion. The electrode to modiolus distance, duration of cochlear implant use, t level are ECAP determinant factor. The value of ECAP can be used as guidance to identify electrode distance deviation and to gain comfortable zone.
Keywords: cochlear implant, ECAP, electrode location, sensorineural hearing loss.