To the Editors:
Familial exudative vitreoretinopathy (FEVR) is an inherited retinal vascular disease characterized by progressive loss of anterior retinal vasculature, especially in the temporal quadrants. Left untreated, preretinal vascular buds arborize into fibrovascular proliferative membranes that produce macular dragging, tractional retinal detachment, vitreous hemorrhage, or profound exudation with Coats-like response.1 Identification of subtle retinal neovascularization is important to facilitate early treatment and prevent vision-threatening complications. Early retinal neovascularization in FEVR may be difficult to identify ophthalmoscopically in darkly pigmented fundi. This report describes a method for using fluorescein dye to define ophthalmoscopically the demarcation line between vascular and avascular retina to facilitate laser treatment in both eyes of two patients with FEVR.
Two sisters, ages 3 and 7 years, were referred for retinal consultation for macular dragging, asymmetric high myopia, amblyopia, and strabismus. Both children were born at term without pregnancy- or birth-related complications. Medical history was unremarkable and family history was significant for visual impairment in their estranged father. Examination under anesthesia was performed on both children to facilitate a scleral depressed examination.
Anterior segment examination was unremarkable in both children. Funduscopic examination revealed changes of pathologic myopia in both eyes, posterior insertion of the vitreous base, and extensive lattice degeneration. Retinal vessels terminated temporally in both eyes in areas of white without pressure, but retinal neovascularization was not apparent against the darkly pigmented fundus background.
Fluorescein angiography demonstrated filling defects and vascular remodeling temporally in early frames in both children. Early and late leakage at the border between vascular and avascular retina indicated retinal neovascularization. Subsequent inspection with indirect ophthalmoscopy 10 minutes after infusion demonstrated green fluorescein dye extravasated into the vitreous overlying the areas of retinal neovascularization that guided ablation of avascular retina.
Figure. RetCAM 3 (Clarity Medical Systems, Inc., Pleasanton, CA) images of the darkly pigmented fundus in the right eye in the younger patient with familial exudative vitreoretinopathy. Contrast was enhanced on these digital RetCAM images because image quality is poor in darkly pigmented fundi. (A) The border of the avascular zone was barely perceptible ophthalmoscopically. (B) A recirculation phase image from the fluorescein angiogram showed leakage from occult retinal neovascularization. (C) The vessels (arrows) became apparent by indirect ophthalmoscopy by fluorescein dye leakage into the pre-retinal space. (D) Laser was applied in a near confluent pattern to include the area of dye leakage.
The extensive vitreoretinal interface abnormalities and heavily pigmented fundus background made visualization of retinal vessels difficult, even in red-free light. The border between vascularized and avascular retina was highlighted by the extravasated fluorescein dye and facilitated laser application. Preoperatively dosed fluorescein dye has been used to enhance vitreous visualization during vitrectomy in vasoproliferative retinopathies.2,3 Fluorescein angioscopy has been applied diagnostically in FEVR, but its therapeutic use in guiding laser ablation is novel.4
Fluorescein sodium can be safely administered intravenously in patients of all ages, including medically frail, preterm infants.5 Fluorescein can be given orally to cooperative children when intravenous access is not possible. We observed no interference from the green fluorescein dye with uptake of the diode green (532-nm) laser, but other wavelengths may be dampened if energy is absorbed by the dye.
This technique may have broader applicability than what is contained in these two cases, including use in other pediatric retinal vascular disorders, eyes where media haze limits identification of retinal vessels, or eyes with retinal pigment epithelium hypopigmentation. It may facilitate ophthalmologists early in their careers during their initial laser procedures treating vasoproliferative retinopathies. This technique could also be employed to identify areas of flat neovascularization in infants with aggressive, posterior retinopathy of prematurity to prevent posterior skip areas.
Robert A. Sisk, MD
Cincinnati Children’s Hospital Medical Center
- Tasman W, Augsburger JJ, Shields JA, et al. Familial exudative vitreoretinopathy. Trans Am Ophthalmol Soc. 1981;79:211–226.
- Yao Y, Wang ZJ, Wei SH, et al. Oral sodium fluorescein to improve visualization of clear vitreous during vitrectomy for proliferative diabetic retinopathy. Clin Experiment Ophthalmol. 2007;35:824–827. doi:10.1111/j.1442-9071.2007.01610.x [CrossRef]
- Kobayashi Y, Yokoi T, Yokoi T, et al. Fluorescein staining of the vitreous during vitrectomy for retinopathy of prematurity. Retina. 2001;31:1717–1719. doi:10.1097/IAE.0b013e318227a9d9 [CrossRef]
- Shukla D, Singh J, Sudheer G, et al. Familial exudative vitreoretinopathy (FEVR): clinical profile and management. Indian J Ophthalmol. 2003;51:323–328.
- Lepore D, Molle F, Pagliara MM, et al. Atlas of fluorescein angiographic findings in eyes undergoing laser for retinopathy of prematurity. Ophthalmology. 2011;118:168–175. doi:10.1016/j.ophtha.2010.04.021 [CrossRef]