Optical Coherence Tomography Angiography Characterization of Evolving Lesions in Fellow Eyes of Exudative Type 3 Macular Neovascularization Patients

Abstract

Purpose: To investigate fellow eyes of newly diagnosed unilateral exudative Type 3 (T3) macular neovascularization (MNV) patients by assessing the presence and progression of a preclinical neovascular component during a 3-year follow-up.Methods: This is a longitudinal study involving three retinal referral centers. Patients affected by unilateral exudative treatment-naive T3 MNV were enrolled.Results: Twenty-four eyes of 24 patients (79 ± 6 years old) were enrolled. Nine eyes (37%) displayed a nonexudative T3 MNV at baseline that developed exudation after a mean of 9 ± 9 months. Fifteen eyes that did not display a nonexudative Type 3 MNV at baseline. Five eyes (21%) did not display neovessels at baseline, but showed a nonexudative T3 after 13 ± 9 months, and exudation after 8 ± 3 months. Five eyes (21%) developed active exudative T3 MNV after 23 ± 9 months, with no detectable nonexudative stage at baseline. Five eyes (21%) did not show MNV, but progressed to geographic atrophy by 36 months of follow-up. Overall, T3 MNV in the fellow eye accounted for 79%, all developing exudation over 3 years of follow-up. Conclusion:The occurrence of a nonexudative T3 MNV is a frequent event in the fellow eye of patients newly diagnosed with unilateral exudative T3 MNV and it precedes the development of exudation over 3 years (prevalence of 37% and cumulative incidence of 79%). Optical coherence tomography angiography approach may be used to perform an early diagnosis and treatment of patients with T3 MNV.

Histology of type 3 macular neovascularization and microvascular anomalies in treated age-related macular degeneration: a case study

“…In addition, registration of pre-mortem eye-tracked OCT volumes to post-mortem OCT volumes of the same globes allows for true in vivo-ex vivo correlation of retinal biomarkers. 33 Limitations include the lack of longitudinal OCTA imaging to visualize anti-VEGF treated vessels over time, 10, 67 and lack of color fundus photography to reveal discoloration patterns typical of type 3 MNV. 14 Limitations to the laboratory study included use of stepped sections that may have missed details such as retinal vascular connections with the choriocapillaris, lack of electron microscopy for all lesions, and lack of immunohistochemistry to support cell type identifications based on published morphologic criteria alone.…”

“…Although one patient, the clinical and imaging characteristics are typical of multifocal type 3 MNV, including bilaterality (55% of cases) 44 and absence of type 1 MNV. 11-13, 44, 45 Type 3 MNV is distinguished by intraretinal origin, 1, 2, 46 frequent near-term bilateral involvement, 7-9 and significant choroidal thinning with reduced perfusion. 47, 48 Patients with type 3 MNV are older at initial diagnosis than patients with type 1 MNV.…”

“…Study strengths include the availability of OCTA with eye-tracked OCT, volumetric projection artifact removal, rapid tissue preservation to largely maintain retinal attachment, registration of pre-mortem and post-mortem OCT volumes, and comprehensive histologic and microscopy techniques to reveal vessels and perivascular tissue elements. Limitations include the lack of longitudinal OCTA imaging 9, 75 and lack of color fundus photography to reveal discoloration patterns typical of type 3 MNV. 14 Limitations to the laboratory study included use of stepped sections, lack of electron microscopy for all lesions, and lack of immunohistochemistry to support cell type identifications based on morphologic criteria.…”

“…7 Fellow eyes often convert to neovascular AMD within 3 years. [8][9][10] Early lesions respond well to intravitreal anti-vascular endothelial growth factor (VEGF) therapy, unlike chronic lesions. 3,11 Recent clinical imaging studies have elucidated type 3 MNV pathophysiology.…”

“…Fellow eyes often convert to neovascular AMD within 3 years. [7][8][9] Early lesions respond well to intravitreal anti-vascular endothelial growth factor (VEGF) therapy, unlike chronic lesions. 2,10 New information about type 3 MNV and related vascular anomalies from histopathology, as provided herein, could support improved detection and treatment decisions in affected patients.…”