Session Title: New Drug Treatment
Session Date/Time: Saturday 13/09/2014 | 14:30-16:30
Paper Time: 15:10
Venue: Boulevard F
First Author: : C.Quijano UK
Co Author(s): : M. Gil-Martinez S. Pastor-Idoate S. Biswas P. Stanga
Juvenile X-linked retinoschisis (XLRS) is a retinal dystrophy caused by a mutation on the XLRS1 gene that affects males in their first decade. Its characteristic feature is foveal schisis in >98% of cases - described as a splitting within the inner retina that appears as cystoid spaces. Radial striae and pigmentary macular changes can be observed. Peripheral retinoschisis occurs in 50% of cases; opaque vitreous bands, vitreous haemorrhage and retinal detachment can be observed. The purpose of this study is to assess changes in visual acuity (VA) and average central retinal thickness (ACRT) in XLRS treated with topical Dorzolamide.
1Manchester Royal Eye Hospital, UK 2Manchester Vision Regeneration (MVR) Lab at NIHR/ Wellcome Trust Manchester CRF, UK 3Manchester Academic Health Science Centre and Centre for Ophthalmology and Vision Research, Institute of Human Development, University of Manchester, UK
Retrospective review of the medical records of six male patients (12 eyes) from the Regional Paediatric Vitreoretinal Service at the Manchester Royal Eye Hospital and diagnosed with X-linked retinoschisis treated with topical Dorzolamide (Trusopt®) three times a day. Age, pre and post treatment best-corrected visual acuity (BCVA), Wide-Field Fundus Autofluorescence Imaging (WF-FAF) (200Tx®, Optos plc) in selected cases and average central retinal thickness (ACRT) on Fourier-Domain Optical Coherent Tomography (FD-OCT) (3D OCT-2000, Topcon Corporation) scans were recorded. All patients underwent slit lamp biomicroscopy, intraocular pressure (IOP) measurements and dilated fundus biomicroscopy.
Mean patient age at the beginning of treatment was 11 years-old (range, 8-16). Follow up was 1.8 months (range, 1-3 months). 67% of eyes experienced an improvement in BCVA after the first month of treatment, while 33% showed no change (p= 0.010). Electrodiagnostics, WF-FAF and FD-OCT confirmed our clinical diagnosis. ACRT improved in all eyes by the third month of follow up (p= 0.022). Reduction in ACRT correlated with improvement in VA (Pearson coefficient result: 0.72). IOP remained within normal limits in all patients across the study. After three months all patients stopped using the eye drops due to intolerance of the side effects.
We report a positive correlation between reduction in ACRT and improvement of BCVA. When lack of correlation existed this could have been secondary to the chronicity and/or severity of the disease or amblyopia. Larger studies with longer follow up are required to assess whether this therapy can actually prevent macular atrophy. No serious adverse effects associated to this therapy were observed although the patients complained of stinging on drop instillation which resulted in poor compliance. Despite objective improvement in ACRT and VA, the efficacy of topical Dorzolamide is reduced due to poor compliance in this group of patients. Strategies to improve compliance with topical anhydrase inhibitors are required.