DR. PRADEEP SAGAR

Dr. MAHESH P. SHANMUGAM, DR. SUCHITRA KUMARI BISWAL, Dr.RAVI SHANKAR H.N.

Abstract

Purpose: To evaluate the efficacy of targeted laser photocoagulation of rim aneurysms in diabetic macular edema (DME).

Methods: Fundus photograph of cases with DME were screened for presence of larger capillary aneurysms with white rim. Optical coherence tomography (OCT) was used to confirm the presence of rim aneurysms, which is detectable as oval structure with hyper reflective margin and hyporeflective lumen. Targeted laser photocoagulation was performed to achieve complete blanching of rim aneurysm.

Results: Eight cases of DME with rim aneurysm were included in the study. Four cases were previously treated with anti VEGF injections with poor response. The cases were treated by targeted laser photocoagulation. Complete resolution of macular edema was noted in 5 eyes, partial resolution in 1 eye and no reduction in 2 eyes during follow up.

Conclusion: Cases with rim aneurysms respond poorly to anti VEGF injections and targeted photocoagulation is effective in resolution of DME

Full Text  

Targeted laser photocoagulation of rim aneurysms in Diabetic Macular Edema

Abstract

Purpose:

To evaluate the efficacy of targeted laser photocoagulation of rim aneurysms in diabetic macular edema (DME).

Methods:

Fundus photograph of cases with DME were screened for presence of larger capillary aneurysms with white rim. Optical coherence tomography (OCT) was used to confirm the presence of rim aneurysms, which is detectable as oval structure with hyper reflective margin and hyporeflective lumen. Targeted laser photocoagulation was performed to achieve complete blanching of rim aneurysm.

Results:

Ten cases of DME with rim aneurysm were included in the study. Four cases were previously treated with anti VEGF injections with poor response. The cases were treated by targeted laser photocoagulation. Complete resolution of macular edema was noted in 6 eyes, partial resolution in 2
eye and no reduction in 2 eyes during follow up. Conclusion: Cases with rim aneurysms respond poorly to anti VEGF injections and targeted photocoagulation is effective in resolution of DME

INTRODUCTION:

Diabetic macular edema (DME) is one of the leading cause of visual impairment in patients with diabetic retinopathy. Leak from microaneurysms and incompetent capillaries results in macular edema. Microaneurysms are usually tiny and measure 25 to 100 micron in size. However, larger aneurysms arising from retinal capillaries are described in diabetic retinopathy and retinal vein occlusions.

Macular edema due to larger aneurysms respond poorly to intravitreal anti VEGF therapy.1,2 Few studies have noted good response to laser photocoagulation in cases with macular edema secondary to larger aneurysms. Indocyanine green angiography and infrared reflectance image are described to be a better imaging modality in identification of such larger aneurysms.2,3 In this series, we describe successful treatment of macular edema with targeted laser photocoagulation in eyes with DME secondary to large aneurysms with rim.

Methodology

This is a retrospective study of eyes with DME secondary to large aneurysms with rim treated with targeted laser photocoagulation from October 2018 to September 2021. Both treatment naïve cases and cases which did not respond to intravitreal pharmacotherapy were included in the study. Best corrected visual acuity (BCVA) was recorded with Snellen’s chart. Color photograph and optical coherence tomography (OCT) was performed with Topcon DRI OCT Triton. Color photographs were screened for the presence of large aneurysms with rim within in the edematous area of macula.

Optical coherence tomography (3D macula protocol) was used to confirm the presence of aneurysm. Aneurysm was seen as a vertically oval structure with hyporeflective lumen and hyper reflective margin. Laser photocoagulation was performed with double frequency Nd:YAG slit lamp indirect delivery. Cases were followed up monthly. BCVA, Color photograph and OCT was recorded at each visit. If the edema was persistent at 3 months, alternate treatment options were recommended. Cases with follow up of at least 3 months were included.

Results

Ten eyes with centre involving DME were included in the study. Six cases were treatment naïve and four cases were previously treated with intravitreal pharmacotherapy with poor response. Six eyes showed complete resolution of macular edema, 2 cases showed partial resolution and 2 cases did not show any signs of reduction by 3 months. Nine of the 10 eyes showed complete occlusion of aneurysm by 3 months. Improvement in visual acuity was seen in all the 6 cases that showed complete resolution of macular edema.

Discussion

Larger aneurysms arising from the capillaries are seen in eyes with DME. It has been described Macular edema secondary to such larger aneurysm does not respond well to intravitreal therapy which results in chronic edema and progressive vision loss. In our study we noted that targeted laser photocoagulation results in occlusion of such aneurysms in most of the cases. Anatomical improvement in terms of resolution of macular edema was seen in 60% of cases. Visual improvement was also seen in 60% of cases. The limitations of the study are retrospective nature of the study, small sample size, variable follow up period. Confounding factors such as glycemic control were not considered.

Reference:

1. Spaide RF, Barquet LA. RETINAL CAPILLARY MACROANEURYSMS. Retina. 2019 Oct;39(10):1889-1895.
2. Castro Farías D, Matsui Serrano R, Bianchi Gancharov J, de Dios Cuadras U, Sahel J, Graue Wiechers F, Dupas B, Paques M. Indocyanine green angiography for identifying telangiectatic capillaries in diabetic macular oedema. Br J Ophthalmol. 2020 Apr;104(4):509-513
3. Roh HC, Lee C, Kang SW, Choi KJ, Eun JS, Hwang S. Infrared reflectance image-guided laser photocoagulation of telangiectatic capillaries in persistent diabetic macular edema. Sci Rep. 2021 Nov 5;11(1):21769.