Abstract
Purpose :
Purpose: Towards validating clinical autofluorescence (AF) imaging for AMD diagnosis and management, we established methods for rapid tissue recovery and characterization by ex vivo MMI of AMD phenotypes in donor eyes destined for immunohistochemistry studies. We sought attached maculas and adequate statistical power, in a reasonable time frame.
Methods :
Method: Recovery criteria were non-diabetic Caucasian donors >80 years of age, with death to preservation time (DtoP) ≤ 6hr. Globes were recovered on-site, scored with an 18-mm trephine to facilitate cornea removal, and immersed in buffered 4% paraformaldehyde. Anterior segment remnants were removed in-house before MMI. Color images were taken with a Nikon D7200 camera mounted to an Olympus SZX9 Stereo microscope
using trans-, epi-, and flash illumination at 3 magnifications. Globes were placed in buffer in a chamber with a 60-diopter lens [1] and imaged with spectral domain optical coherence tomography (SDOCT) (30° macula cube, 30 µm spacing, averaging ≥50), near-infrared reflectance (NIR), 488 nm AF, and 787 nm AF (Spectralis HRA&OCT, HRA2; Heidelberg Engineering). Images and globes were reviewed with a retina specialist. Criteria for AMD is RPE change with drusen and subretinal drusenoid deposits, with or without neovascularization, and without evidence of other causes.
Results :
Results: Between 06/16- 09/17, 94 pairs of donor eyes were recovered. DtoP decreased during this period (mean at start, 4.36 hr; at finish, 3.47 hr). Of 184 eyes reviewed, 40.8% had certain AMD: Unremarkable (39.7%), Questionable (11.4%), Early (22.8%), Atrophic (7.6%, Fig. 1), Neovascular (9.8%, Fig. 2), Other (8.7%). Unusual presentations recognizable from clinical MMI included an Onion [1], nevi with drusen, [2] and pachyvessels [3].
Conclusions :
Conclusion: Within 14 months, 75 rapid DtoP donor eyes with AMD and 73 with unremarkable maculas were recovered and staged using MMI methods familiar from our prior experience with histologic validation of SDOCT. With these came unusual cases that cannot be predicted but are valuable on their own. Many RPE phenotypes are common to all AMD stages [4], making all stages informative for AF validation.
1. Pang. Ophthalmology 2015, 122:2316
2. Francis. Am J Ophthalmol 2015, 159:169
3. Inoue. Retin Cases Brief Rep 2016, 10:22
4. Curcio. IOVS 2017, 58, BIO211
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.