Long term follow-up of visual acuity and incidence of subretinal neovascularization in Mactel Type 2 in 82 Eyes

ABSTRACT

Purpose

: To evaluate the long-term natural course of macular telangiectasia Type 2, correlation with visual acuity and the incidence of Choroidal Neovascularisation (CNV) in Indian eyes.

Material and methods

: A Retrospective analysis of Patients with MacTel Type 2 was done over a period of 12 years with all patients having a minimum of 3 years follow up. The demographic details and ocular characteristics including best-corrected visual acuity (BCVA), fundus photography, fluorescein angiography, and optical coherence tomography images were studied in both proliferative and non-proliferative MacTel. Mixed models were used to estimate progression rates and a Kaplan Meier estimation of BCVA was plotted.

Results

: Eighty-two eyes of 47 patients were studied over a period of mean duration of 4.5 years (range: 3 years-8.5 years). There was no difference in the demographic characteristics between the non-proliferative MacTel and proliferative MacTel groups. There were no significant risk factors observed for progression. However, patients with retinal greying had significant risk reduction for a BCVA decline. The mean logMAR BCVA decreased from 0.25 ± 0.25 at baseline to 0.46 ± 0.42 by 4 years. Twenty-eight percent of the patients maintained their vision 8 years from baseline and were unlikely to progress. The incidence of CNV was 10.6% and the mean duration for the development of CNV was 2.36 years from baseline. Seventy-Three percent (11 of 15) patients with CNV had a BCVA of <20/40.

Conclusion

: In patients of MacTel, the maximum vision loss occurred at the fourth year and then stabilized. The major cause of poor vision observed was CNV (active in 10.98% and scarred in 7.32%), foveal atrophy (10.98%) and central pigmented plaques (3.66%). The incidence of sight-threatening complication of CNV (10.6%) is likely to occur only in a minority of eyes.

KEYWORDS:

• MacTel type 2
• choroidal Neovascularization
• Indian eyes
• Natural history
• neovascularization
• Disease progression
• Visual acuity

Disclosure Statement

The authors declare no conflict of interest.

Additional information

Funding

The IHOPE Centre is Funded by Department of Biotechnology, Government of India, and The Wellcome Trust, United Kingdom (India Alliance)DBT India;