Long-term Progression of Type 1 Neovascularization in Age-related Macular Degeneration Using Optical Coherence Tomography Angiography

Purpose: To investigate whether qualitative and quantitative features of choroidal neovascular membranes are associated with anti-vascular endothelial growth factor treatment response in patients with neovascular age-related macular degeneration. Methods: A total of 41 eyes were included in this cross-sectional observational study and divided into “good responders” and “poor responders” based on the long-term functional changes, frequency of recurrent choroidal neovascular activity, and injection need. Enface optical coherence tomography angiography images were obtained and qualitative features of choroidal neovascular membranes were described based on vessel network density. Then, quantitative measurements including vessel area, vessel length, junction density, and lacunarity were calculated using validated software (ImageJ and AngioTool). Chi-square tests, t-test, or Mann–Whitney U tests were used for group comparisons, and intraclass correlation coefficients were calculated for reliability assessment of quantitative analyses. Results: Twenty-two eyes treated by a median of 9 (3–24) anti-vascular endothelial growth factor injections at a median follow-up of 41 (12–89) months were categorized as good responders, 19 treated by a median of 26 (11–46) injections at a median follow-up of 44.5 (12–84) months as poor responders. Good responder group mostly had loose network (45.5%), and poor responders mostly had dense network (47.7%). The difference was not statistically significant (p = 0.25). The size of the lesion was 2.7 times greater at baseline (p = 0.04) and 1.7 times greater at final examination in the poor responder group (p = 0.04). Lacunarity index, showing lesion heterogeneity, was higher in good responders (p = 0.018) than poor responders. Other quantitative vascular features did not significantly differ between the groups (p > 0.05). Conclusion: Long-term remodeling of chronically treated choroidal neovascular may be non-invasively and reproducibly investigated using optical coherence tomography angiography. Quantitative analysis and lacunarity index, in particular, may be used as a measure of vessel maturation and guide treatment strategies in neovascular age-related macular degeneration.

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Comparison of optical coherence tomography angiography features in type 1 versus type 2 choroidal neovascular membranes secondary to age-related macular degeneration

Medical hypothesis discovery and innovation in ophthalmology ◽

10.51329/mehdiophthal1423 ◽

2021 ◽

Vol 10 (2) ◽

pp. 25-31

Author(s):

Yasin Sakir Goker ◽

Gokhan Demir

Keyword(s):

Optical Coherence Tomography ◽

Macular Degeneration ◽

Optical Coherence Tomography Angiography ◽

Age Related Macular Degeneration ◽

Optical Coherence ◽

Dead Tree ◽

Flow Area ◽

Age Related

Background: Optical coherence tomography angiography (OCTA) is an advanced imaging modality that provides high resolution images at the level of different retinal layers. This study aime to evaluate choroidal neovascular membranes (CNVMs) secondary to age-related macular degeneration (AMD) quantitatively and qualitatively, according to their classification, morphological features, and flow areas, using OCTA. Methods: In this descriptive, comparative, cross-sectional study, CNVMs were divided into 2 groups according to their classification as type 1 or type 2 neovascularization. Mixed CNVMs were excluded from the study. The size (mm2) and the flow area (mm2) of the CNVMs were calculated via OCTA and the presence of the perivascular halo and loop anastomoses were analyzed. The morphological appearance of the CNVMs were classified as: medusa, sea-fan, lacy-wheel, glomerular, dead tree, and mature vascular networks. Results: Of the 85 eyes assessed for eligibility, 45 eyes of 34 individuals with CNVM were enrolled in this retrospective study. Twenty-eight eyes had type 1 and 17 eyes had type 2 CNVMs. The mean size and flow area were greater in type 1 than in type 2 CNVMs (mean ± standard deviation [SD], 6.69 ± 4.54 and 3.61 ± 3.56 mm2 versus 3.04 ± 1.98 and 1.77 ± 1.62 mm2; P = 0.044 and 0.046, respectively). Among the 22 eyes with type 1 CNVMs and the 9 eyes with type 2 CNVMs, 31 eyes had exudative membranes. Among the eyes with exudative CNVMs, 22 eyes had a perivascular halo and 22 eyes had loop anastomoses; this was significantly more than in the non-exudative eyes (P = 0.042 and 0.041, respectively). The lacy-wheel (38.7%) and dead tree (71.4%) patterns were the most frequent morphological appearance of the CNVMs in the exudative and non-exudative membranes, respectively. Conclusions: OCTA provides objective documantation about CNVMs. A perivascular dark halo around CNVMs could be a criterion to define exudative membranes activity. How to cite this article: Goker YS, Demir G. Comparison of optical coherence tomography angiography features in type 1 versus type 2 choroidal neovascular membranes secondary to age-related macular degeneration. Med Hypothesis Discov Innov Ophthalmol. 2021 Summer; 10(2): 25-31. https://doi.org/10.51329/mehdiophthal1423

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