Posisi elektroda intrakoklea dan ECAP sebagai pedoman pemetaan pada tuli sensorineural dengan implan koklea
Authors: Zizlavsky Semiramis , Restuti Ratna Dwi , Pandelaki Jacub , Mansyur Muchtaruddin , Hermani Bambang , Ranakusuma Teguh , Eddin Edrial , Waspadji Sarwono 
Published: September 2018

Latar belakang: Implan koklea merupakan pilihan utama untuk habilitasi pendengaran dan berbicara pada anak tuli sensorineural berat bilateral. Pengaturan comfortable dan threshold level berdasarkan nilai evoked compound action potential (ECAP) direkam dengan neural responses imaging (NRI) saat 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. Metode: Anak tuli sensorineural usia 2-10 tahun, menggunakan implan koklea dengan desain contour atau straight terdiri dari 16 elektroda, 120 channel sebagai subjek penelitian. Subjek penelitian sebanyak 46 telinga (39 anak), terpasang implankoklea diperoleh secara konsekutif dengan desain potong lintang. Perekaman ECAP 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 untuk menilai posisi dan jarak elektroda. Analisis data diawali dengan univariat dan uji korelasi Spearman ‘s pada bivariat. Kandidat faktor yang berperan disertakan pada regresi ganda untuk mendapatkan faktor determinan ECAP. Comfortable zone untuk populasi diperoleh dari analisis area pada distribusi normal menggunakan comfortable level. Hasil: Diperoleh persamaan yaitu: (rerata ECAP)=-21,19+5,87 rerata jarak elektroda ke modiolus (mm)+1.31, rerata threshold level (cu)+0.48 lama penggunaan implan koklea (bulan). (R square=0.60). Comfortable zone diperoleh dengan ECAP yang berada pada variasi 84-87,5% comfortable level. Kesimpulan: Jarak elektroda ke modiolus, lama penggunaan implan koklea dan t level merupakan faktor determinan ECAP. Nilai ECAP dapat digunakan untuk mengidentifikasi penyimpangan jarak elektroda dan memperoleh comfortable zone.Kata kunci : ECAP, implan koklea, lokasi elektroda, tuli sensorineuralABSTRACT Background: Currently cochlear implant remains a preferred choice in hearing and speechhabilitation in children with bilateral profound SNHL. Comfortable and threshold level setting based on ECAP value is recorded by NRI during mapping. Purpose: To obtain ECAP value as mapping guidance based on the distance between electrode to modiolus, the longest distance between electrode number one with the ones it faces, the distance between marker and cochleostomy and other factors. Methods: Research subject were children with SNHL, between 2-10 years old using CI with 16 electrodes, 120 channels. There were 46 ears (39 children) with CI chosen consecutively by cross sectional design. Using NRI, ECAP was recorded on electrode 3-5, 8-10, 13-15 that represent the apex, medial and basal area. Their cochlears were examined with HRCT then 3D reconstruction with OsiriX programto determine the electrode position and calculate the distance. Data analysis started with univariat 1 and bivariat with Spearman’ correlation. Candidates’ factor were analysed with multiregression test to gain ECAP determinant factor. Comfortable zone for population was gained from area analysis in normal distribution using comfortable level. Results: The equation found were: y (average ECAP)=21.19+5.87 the average electrodes to modiolus distance (mm)+1.31, threshold level (cu)+0.48 CI length use (months). (R square=0.60).Comfortable zone was acquired with ECAP between 84-87,5% comfortable level variation. Conclusion: The electrode to modiolus distance, duration of CI use and 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, sensoryneural hearing loss