RBCs |
H&E |
Intact |
First 24 h |
Differentiation from autolytic mechanisms by comparison with other structures |
Lysed |
From 2 to 24 days |
Mixed |
Fibrin/platelets |
H&E |
Presence/Absence |
First 72 h |
- |
Leukocytes |
H&E |
PMNs and/or lymphocytes |
PMNs from 12 h to 17 days (peak within 48–96 h); lymphocytes from 12 h to 23 days (peak within 72–96 h) |
- |
Macrophages |
CD68 immunolabeling |
200× magnification field count for semi-quantitative study |
From 72 h (minimal PTI observed: 12 h) |
Cells per filed proposed: 0–3 |
Hemoglobin degradation |
Perls Prussian blue stain |
Detection of siderophages and/or hematoid deposits within affected tissue |
From 72 h |
Semi-quantitative classification as absent, early, moderate, or abundant |
Neovascularization |
H&E |
Absent/present |
From the 6th to the 70th day |
Grades of presence: capillary proliferation, giant capillaries, arterioles |
Fibrous organization |
H&E |
Absent/present |
From the 2nd week |
Aspects of retinal sclerosis or ON atrophy |