Early chorioretinal anastomosis in non-ischaemic CRVO: a randomised trial
- Department of Ophthalmology, St Thomas’s Hospital, Lambeth Palace Road, London E1 7EH, UK
- Correspondence to: Eric Mayer University of Bristol, Clinical Sciences, Bristol Eye Hospital, Lower Maudlin Street, Bristol BS1 2LX, UK; e.mayerbristol.ac.uk
- Accepted 14 January 2005
In non-ischaemic central retinal vein occlusion (niCRVO), the two principal determinants of final visual acuity are visual acuity and the presence of macular oedema at initial presentation.1,2 Data from the Central Vein Occlusion Study Group2 suggested that of patients with CRVO with an initial acuity better than 6/15, 65% maintain this, whereas patients with presenting acuities between 6/15 and 6/60, 81% remain the same or get worse (19% improve to 6/12 or better, 44% remain between 6/15, and 6/60 and 37% are worse than 6/60). Up to 34% of niCRVO may progress to the ischaemic variant with its attendant complications within 3 years.2 However, in some studies 83% of indeterminate cases progress to ischaemic CRVO.1 The creation of a chorioretinal venous anastomosis (CRVA) improved visual acuity in some patients, decreased macular oedema, and reduced the incidence of progression to ischaemic CRVO.3–5 These important observations provide the basis for the study we carried out.
During the study period 11 patients (table 1) were enrolled according to the trial protocol (see appendix). All anastomoses were patent (on fluorescein angiography and if not repeated, see appendix). Mean patient age and mean pretreatment (T0) visual acuities, retinal thickness (by optical coherence tomography, …
