Retinoschisis – acquired degenerative

DESCRIPTION MANAGEMENT Retinoschisis is a splitting within the sensory , and may occur in age- Additional investigations related degenerative and X-linked reces- The work-up for retinoschisis involves sive forms (see next week: Retinoschisis ruling out the presence of a retinal – Juvenile X-Linked). Degenerative detachment, or an outer layer retinal hole retinoschisis is an acquired condition using indirect ophthalmoscopy with involving a splitting of the sensory retina, scleral depression. If the retinoschisis usually within the plexiform layers, extends posteriorly, beyond the equator, creating a large ‘cyst’. Degenerative an absolute visual field defect may be retinoschisis initially occurs in the far found (60º visual field test). retinal periphery, beginning with an area of microcystoid degeneration, a Advice degenerative change adjacent to the Most cases of retinoschisis are innocu- ora serrata that is common to all adult ous and do not affect central vision or eyes. A secondary retinoschisis may require treatment. They usually remain present in other ocular diseases such as Retinoschisis, with arrows at the edge of the stable for years. diabetic and retinopathy of bullous area. There is a generally thinned prematurity. retinal pigment epithelium and evident Laser surgery choroidal vasculature Laser treatment should be considered SYMPTOMS if the retinoschisis is progressive and Often the condition is asymptomatic. threatens the macula. However, visual acuity may be abnor- mal if the retinoschisis or an associ- Incisional surgery ated involves the Surgery is indicated if there is a risk of macula. retinal detachment or if a retinal detach- ment has occurred. SIGNS Degenerative retinoschisis is most Review commonly observed in the inferior Routine review is warranted at six to temporal quadrant of the fundus. The 24-month intervals, depending upon schisis may assume a smooth, dome- the lesion size, the proximity to the shaped appearance (bullous) of trans- macula and the presence or absence parent retina that has a discrete border of symptoms. The patient should be and is immobile. The inner surface of advised to return urgently if they experi- the elevated zone may manifest a frosted Retinoschisis in a 59-year-old asymptomatic ence retinal detachment symptoms, such or snowflake-like appearance, and blood hyperopic patient. The ultra-wide field (200º) as increased or flashing lights or vessels on the inner layer may be white image is via the Optos Optomap scanning laser the presence of a curtain or shadow in and sheathed. Holes can develop in system (courtesy J Pilbeam, Loughborough, UK) their field of vision. both inner and outer layers, creating a risk for secondary retinal detachment. Circumferential and, rarely, posterior progression can occur. When bilateral, as it usually is, the presentation is typically symmetrical DIFFERENTIAL DIAGNOSIS The full series of these articles is available in the book between the eyes. The condition may be X-linked juvenile retinoschisis; Retinal Posterior and A-Z by Bruce AS, slowly progressive in some cases. detachment – rhegmatogenous. O’Day J, McKay D and Swann P. £39.99. For further The following features of a degenera- information click on the Bookstore at opticianonline.net PREVALENCE tive retinoschisis may assist in differen- Degenerative retinoschisis is seen in tiating it from a retinal detachment: ● Adrian Bruce is a Chief Optometrist at the Victorian about 5-7 per cent of the adult popula- ● Discrete border to the lesion, with a College of Optometry and a Senior Fellow, Department tion and is usually associated with smooth surface of Optometry and Vision Sciences, The University of hypermetropia. ● Immobile during eye movements Melbourne. ● No associated pigment in the ● Justin O’Day is an Associate Professor in the SIGNIFICANCE vitreous Department of , The University of Since the inner retinal layer becomes ● No changes in the retinal pigment Melbourne and Head Of Neuro-Ophthalmology Clinic, elevated, retinoschisis may mimic a epithelium Royal Victorian Eye and Ear Hospital. retinal detachment. Rarely, degenerative ● Usually asymptomatic, with no float- ● Daniel McKay is a Medical Officer at the Royal retinoschisis can lead to retinal detach- ers, photopsia, or ‘curtain’ effects Victorian Eye & Ear Hospital. ment. Retinoschisis has been reported in ● Often bilateral ● Peter Swann is Associate Professor in the School of approximately 2.5 per cent of patients ● Can be associated with a visual field Optometry, Queensland University of Technology. with retinal detachment. defect. opticianonline.net 20.06.08 | Optician | 59