Experimental microablation of choroidal tissue for autologous retinal pigmentepithelium-choroid translocation with the pulsed electron avalanche knife (PEAK-fc).
Résumé
Aim: To test the microablation of excess graft choroidal tissue with the pulsed electron avalanche knife (PEAK-fc) in an in-vitro model of autologous retinal pigment epithelium (RPE)-choroid translocation. Methods: Choroidal tissue of porcine RPE-choroid explants was ablated with the PEAK-fc. Tissue morphology was assessed by light microscopy (LM) and scanning electron microscopy (SEM). The amount of ablated choroidal tissue was analysed as a function of three PEAK-fc parameters: (1) amplitude of biphasic voltage (70-100 %), (2) distance between choroidal tissue and tip of the PEAK-fc (0-300 µm), (3) exposure time (2-8 s). Results: LM and SEM showed a smooth plain within the ablation area with well defined cutting edges and preserved adjacent tissue structure. The mean amount of ablated tissue correlated linearly with (1) applied voltage (range: 79 to 120 µm, r=0.34) and (2) distance between choroidal tissue and PEAK-fc tip (range: 10 to 100 µm, r=0.74). (3) The mean amount of ablated tissue increased with exposure time between 2 and 4 s (36 to 88 µm, r=0.4) and remained constant between 4 and 8 s. Conclusion: The PEAK-fc accurately microablates choroidal tissue in-vitro. The adjacent choroidal tissue structure and Bruch's membrane are preserved. Patient studies are required to test the PEAK-fc in RPE-choroid translocation surgery.
Origine : Fichiers produits par l'(les) auteur(s)
Loading...