Abstract
Purpose: :
To determine if patients with NAMD who initially showed improvement on optical coherence tomography (OCT) in response to treatment with Avastin subsequently develop tachyphylaxis following multiple intraocular injections.
Methods: :
Retrospective chart review of patients with diagnosis of NAMD from 01/2006 to 3/2008 identified 20 eyes that were treated with intraocular Avastin who all met the following criteria: 1) Initial response to Avastin with resolution of fluid on OCT 2) A minimum of 5 intraocular injections and 3) A recurrence of intraretinal/subretinal fluid on OCT. At the time of recurrence Avastin was re-injected, and an OCT image was obtained 2-3 weeks later, to evaluate persistence of fluid on OCT (possible Tachyphylaxis). Patients that were determined to have tachyphylaxis were re-examined 2-3 weeks later and injected with ranibizumab (Lucentis).
Results: :
All eyes had initial improvement on OCT following intraocular injection of Avastin, which ranged from 5 to 16 injections (8.3± 4). The first 3 intraocular injections were given at an interval of 4 weeks, and then the interval was 6 weeks. Overall, 14 eyes (74%) had improvement of at least one line in visual acuity, and 9 eyes (47%) 3 lines of improvement from their first visit. At the time of determining tachyphylaxis, when OCT was obtained 2-3 weeks following re-injection of Avastin it showed that 13 eyes (65%) had resolution of fluid on OCT, and 7 eyes (35%) had persistence of fluid or tachyphylaxis. When switched to Lucentis 5 eyes(71%) had resolution of fluid, and 2 eyes (29%) remained unresponsive.
Conclusions: :
Tachyphylaxis following multiple intraocular injections of Avastin occurred in about third of the eyes with NAMD. Most eyes with tachyphylaxis responded when switched to Lucentis. About two thirds of eyes had resolution of intraretinal/subretinal fluid when the interval of re-injection of Avastin was shortened from 6 to 4 weeks.
Keywords: age-related macular degeneration • macula/fovea • retina