Coats retinopathy with pachychoroid and central serous chorioretinopathy in the fellow eye

Abstract

A 37-year-old man presented with blurring of vision and scotoma in the left eye since last 2 weeks and has a history of poor vision in his right eye since childhood. On examination, his best corrected visual acuity in the right eye was counting finger 1 m and 20/20, N/12 in the left eye. Fundus examination revealed features of Coats disease in the right eye and central serous chorioretinopathy (CSCR) in the left eye. He was given intravitreal triamcinolone acetonide injection in the right eye for reducing subretinal exudation. Simultaneously, focal laser photocoagulation was done to the CSCR leaks in the left eye to prevent the possible worsening of CSCR due to steroid injection in the fellow eye. He underwent cryotherapy to the retinal telangiectatic vessels 3 weeks after steroid injection in the right eye. Optical coherence tomography (OCT) of both eyes showed pachy vessels with a compression of overlying choriocapillaries. After 1 month, the condition of the right eye was unchanged and the CSCR in the left eye was completely resolved with the recovery of near visual acuity.

Background

Coats disease is a non-hereditary idiopathic telangiectasia of retinal vessels with intraretinal or subretinal exudation.¹ It is a disease of retinal vasculature in which abnormal retinal telangiectasia leads to subretinal exudation and hard exudates. Choroidal abnormalities in Coats disease are not widely reported. We present a case of Coats retinopathy with pachychoroid and central serous chorioretinopathy (CSCR) in the fellow eye.

Case presentation

A 37-year-old man presented with blurring of vision and scotoma in the left eye’s field of vision since the last 2 weeks while reading and has a history of low vision in the right eye since childhood. On examination, his best corrected visual acuity in the right eye was counting finger 1 m and the left eye it was 20/20, N/12 for near. Anterior segment examination was unremarkable in both eyes. Intraocular pressure in the right eye and the left eye was 10 and 14 respectively. Dilated fundus examination of the right eye revealed massive subretinal exudation with inferior exudative retinal detachment, subfoveal fibrosis with hard exudates and dilated telangectatic vessels (figure 1A). In the left eye, fundus showed retinal pigment epithelial changes superior to optic disc and inferior to fovea (figure 2A). The patient was advised ancillary investigations, the results of which were suggestive of Coats disease in the right eye and CSCR in the left eye with pachychoroid in both the eyes.

Figure 1.

(A) Fundus picture of the right eye showing subretinal exudation with dilated telangectatic vessels and exudative retinal detachment. (B) FFA of the right eye showing light bulb-like appearance of telangectatic vessels (yellow arrow head), staining of macular fibrosis, pooling of dye temporal to macula in areas of exudative retinal detachment and few capillary non-perfusion areas. (C) OCT of the right eye showing hyper-reflective macular fibrosis, perifoveal increased choroidal thickness with pachyvessels (red circles) compressing choriocapillaries and temporal retinal detachment (yellow arrow). (D) B-scan ultrasonogram showing inferior retinal detachment (blue arrow) with increased choroidal thickness (1.64 mm). FFA, fundus fluorescein angiography; OCT, optical coherence tomography.

Figure 2.

(A) Fundus picture of the left eye showing hypopigmented retinal pigment epithelial changes inferotemporal to disc. (B) FFA of the left eye showing the ink blot pattern of leak inferior to fovea (yellow arrow head) and few window defects superior to the optic disc. (C) OCT of the left eye showing neurosensory detachment with pachy choroidal vessels underneath it (yellow arrow) causing compression of sattlers layers and choriocapillaries. (D) Autofluorescence imaging of the left eye showing gravitational track marks (red arrow) inferior to macula. FFA, fundus fluorescein angiography; OCT, optical coherence tomography.

Investigations

Fundus fluorescein angiography (FFA) of the right eye (figure 1B) showed light bulb-like appearances of retinal telangectatic vessels, perifoveal hyperflourescence of dye due to staining of macular fibrosis, pooling of dye in the areas of exudative retinal detachment and capillary nonperfusion areas in periphery. FFA of the left eye showed the ink blot pattern of leak inferior to fovea and window defects superior to the optic disc (figure 2B).

Optical coherence tomography (OCT) of the right eye (figure 1C) showed exudative retinal detachment temporal to macula, macular scar, and the left eye showed perifoveal subretinal fluid with thickened choroidal vessels inferior to fovea (figure 2C).

B-scan ultrasonography of the right eye showed inferior exudative retinal detachment with minimally increased choroidal thickness (1.64 mm) (figure 1D).

Fundus autofluorescence of the left eye showed central hypoautofluorescence with surrounding granular hyperautofluorescence (gravitational track marks) inferior to fovea (figure 2D).

Treatment

An intravitreal triamcinolone acetonide (IVTA) injection was planned for the patient, followed by the laser photocoagulation of retinal telangiectasia after 3 weeks in the right eye. Simultaneously, focal laser photocoagulation was done to the CSCR leaks in the left eye to prevent the possible worsening of CSCR due to steroid injection in the fellow eye. However, at end of 3-week follow-up of IVTA injection in the right eye, subretinal exudation increased, making the laser photocoagulation unfeasible. Hence, cryotherapy was done to active retinal telangiectatic vessels.

Outcome and follow-up

After a month, the condition of the right eye was unchanged. The CSCR in the left eye was completely resolved with an improvement of near visual acuity from N12 to N6. The OCT showed complete resolution of the subretinal fluid in the left eye (figure 3).

Figure 3.

OCT of the left eye at last follow-up 1 month after focal laser showing completely resolved neurosensory detachment (red arrow) with pachy choroidal vessels underneath it. OCT, optical coherence tomography.

Discussion

Coats disease is a non-hereditary retinal vascular disorder associated with retinal telangiectasia and intraretinal or subretinal exudation.¹ Our case showed an interesting feature of pachychoroid with overlying Coats retinopathy in one eye and CSCR in the fellow eye. CSCR as a cause of pachychoroid has been well reported.² However, similar pachychoroid association in Coats retinopathy is relatively unknown.

The goal in treating Coats disease is to obliterate abnormal, leaking telangiectatic retinal vessels. Shields et al¹ described various treatment modalities in Coats disease based on their stage of presentation. Choice of intravitreal agents as a monotherapy³ or in combination with cryotherapy for treatment of stage 3 Coats disease varies among clinicians. Shields et al¹ observed that 3 out of 16 patients with advanced disease, managed with observation, developed painful secondary glaucoma, requiring enucleation. Our patient had poor vision in his right eye since childhood; however, fundus examination showed active retinal telangectasia prompting us to treat his right eye. If left untreated, a few of these eyes might develop secondary neovascular glaucoma,⁴ phthisis bulbi and painful blind eye requiring enucleation. For our patient, we planned IVTA injection followed by laser photocoagulation. However, as the subretinal fluid had increased in the interim 3 weeks, we opted for cryotherapy.

In our case, focal laser photocoagulation was done to CSCR leaks to prevent possible worsening of CSCR due to steroid injection in the fellow eye. Georgalas et al⁵ found worsening of CSCR in the fellow eye after an Ozurdex implant in an eye with the Irvine-Gass syndrome.

The OCT of our patient in the eye with Coats disease showed pachyvessels and increased perifoveal choroidal thickness. The fellow eye showed pachyvessels with neurosensory detachment and focal leaks, suggestive of chronic CSCR.⁶ Ong et al⁷ studied the macular feature in eyes with Coats disease and found that there is no correlation between the subfoveal choroidal thickness and improvement of visual acuity with treatment. However, the study did not mention the mean choroidal thickness in each case.

Our patient had clinical features of stage 3B Coats disease with subfoveal fibrosis and back shadowing on OCT, curtailing our assessment of the subfoveal choroid. However, it showed perifoveal pachyvessels with increased choroidal thickness, while the B-scan ultrasonogram too showed minimally increased choroidal thickness (1.64 mm). It is difficult to calculate choroidal thickness in advanced cases of Coats disease with subfoveal fibrosis and plaque of hard exudates at fovea which cast shadow on underlying choroid. However, the fellow eye may give us a clue. Sometimes, it is possible that choroidal thickness starts to increase along with macular exudation, which may be normal in early stages.

Though Coats disease is primarily a disease of retinal vasculature, our case report gives new insights into possible pachychoroid nature of disease. By looking retrospectively at the choroidal thickness in cases of Coats disease and its fellow eyes, we may find out whether this finding is just a coincidence or truly an association.

Patient’s perspective.

The vision in my right eye has been poor since childhood. However, I am concerned about my left eye. Now I am satisfied that after laser treatment, the scotoma in my left eye has reduced. I am much more comfortable with my left eye’s vision.

My doctors have explained the risk factors of central serous chorioretinopathy and the chances of recurrence. I shall be watchful of any possible symtpoms.

Learning points.

• Combination of Coats retinopathy and central serous chorioretinopathy (CSCR) can occur in the setting of pachychoroid spectrum.

• Multimodal imaging using enhanced depth optical coherence tomography, autofluorescence, fundus fluorescein angiography and Indocyanine green angiographyICG is essential for accurate diagnosis of underlying pachychoroiddiseases.

• Focal laser photocoagulation for CSCR leaks can be considered, at presentation, to prevent possible worsening when steroid therapy is given in the fellow eye.