 Answers | |  |
Answer 1[Figure 2] shows a dysplastic optic nerve. There is no macular or foveal reflex. A fibrovascular stalk is extending anteriorly from the optic nerve, and appears to be attached to posterior surface of lens. The retina is attached. In
[Figure 3], B-scan ultrasound shows attached retina and a hyper-echoic band (low-medium amplitude) extending from the retina to the lens.
Answer 2Bilateral persistent fetal vasculature (PFV) (microcornea, microphthalmos, OD - fibrovascular stalk from retina to lens and dysplastic disc, OS congenital retinal detachment).
Bilateral vitreoretinal dysplasia
Familial exodative vitreoretinopathy (FEVR)
Retinopathy of prematurity (ROP)
Answer 3 - Elecroretinography - to determine function of retina OD.
- Magnetic resonance imaging (MRI) of brain and orbit - to determine ocular pathology, and if any associated orbital or brain anomaly.
- Fluorescein angiography (FA) - to evaluate peripheral retinal vasculature for anomalies seen in FEVR.
- Genetic evaluation - to determine if any genetic etiology (particularly in case of vitreoretinal dysplasia or FEVR).
| Discussion | | |
PFV, previously referred to as persistent hyperplastic primary vitreous (PHPV) is a developmental malformation of the eye that results from failure of regression of the primary hyaloid and other intraocular (pupillary membrane, tunica vasculosa lentis) vessels. This condition is usually unilateral but can be bilateral (2.4-11%). When bilateral, genetic evaluation is indicated to rule out systemic syndromes like trisomy 13, trisomy 15, trisomy 18, Norrie disease,
Walker-Warburg syndrome More Details, oculopalatocerebral dwarfism, and oculodento-osseous syndrome.
Diagnostic clues for PFV include, microphthalmia, prominent radial vessels in the iris, elongated ciliary process, cataract, presence of retrolental brittle-star malformation and presence of remnants of the hyaloids artery or its branches in the Cloquet canal or on the surface of elevated retina.
In the presence of dense cataract with poor visualization of the retrolental detail; other procedures that can help establish the diagnosis are ultrasonic A-Scan and B-Scan, computed tomography (CT) scan, FA, and MRI of the orbit and the brain.
Ultrasonic evaluation can show microphthalmia and distortion of the eyeball. Characteristic CT scan findings of PFV are absence of calcification, radio dense retrolental soft tissue which enhance with contrast, small irregular lens, decubitus positioning showing a gravitational effect on fluid-fluid level, flattening or indentation of the eye wall. MRI findings of PFV consist of a tubular structure representing the hyaloid vessel, a funnel-shaped retinal detachment with the subretinal fluid hyperintense on both T1- and T2-weighted images. FA can show the retrolental brittle-star and the presence of various abnormal vascular structures associated with PFV.
Bilateral PFV can be differentiated from advanced ROP by history of a prematurity, low birth weight infant undergoing prolonged supplemental oxygen therapy. It can be differentiated from vitreoretinal dysplasias by patent hyaloid vessels on FA. Complications of PFV includes angle closure glaucoma (ACG), retinal detachment, intraocular hemorrhage, ciliary body detachment, and subsequent phthisis bulbi and patients therefore need periodic follow up.
Management may include lensectomy to clear media opacity to allow visual development or simply to prevent ACG. Aggressive amblyopia therapy is required in unilateral cases. Prognosis is less favorable when there is posterior segment involvement.
