|LETTER TO EDITOR
|Year : 1997 | Volume
| Issue : 4 | Page : 261-262
Central retinal vein occlusion study
K S Sangha
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sangha K S. Central retinal vein occlusion study. Indian J Ophthalmol 1997;45:261-2
This communication concerns the article by Saxena. In this article the author does not make a reference to the visual acuity (VA) in central retinal vein occlusion. The central vein occlusion study and even some older studies have made wonderful recommendations based upon the initial VA of patients. According to them, there is a strong corelation of the VA with the perfused versus non-perfused status of CRVO. Some studies rank VA (followed by kinetic perimetry, relative afferent pupillary defect, and ERG, in that order) as a better prognostic indicator than fluorescein angiography. It has been suggested that poor initial VA and a drop in VA during the natural history of the disease are a pointer towards non-perfused status and the conversion from perfused to non-perfused state, respectively.
This in effect means that once diagnosed as CRVO, all cases need not be referred to a retina specialist. As per CVOS guidelines these patients can be divided, prognostically, into three groups.
- a. Those with VA <6/60 have a poor visual prognosis (80% remain at that level or worse). Such a patient is likely to have a non-perfused retina.
- b. Those having VA between 6/60 and 6/15 have variable visual prognosis. These patients may be informed that their VA may improve (1 in 5 chance approximately), may stay at the same level (nearly half do so), or may get worse.
- c. If initial VA is ≥6/12, there is a good likelihood of retaining good vision and the retina is likely to be perfused.
It follows logically that patients in the last group do not need a retinal evaluation from a retina specialist. Those in the second group may need a retinal evaluation, and those in the first group should definitely be referred to a retina specialist. Another important fact to remember is that any drop in VA in any group is a bad omen, and should be taken seriously, both by the general ophthalmologist and the treating retina specialist.
| References|| |
Saxena S. Laser photocoagulation in retinal vein occlusion: Branch Vein Occlusion Study and Central Vein Occlusion Study recommendations. Indian J Ophthalmol
The Central Vein Occlusion Study Group. Natural history and clinical management of CRVO. Arch Ophthalmol
Hayreh SS, Klugman MR, Beri M, Kimura AE, Podhajsky P. Differentiation of ischaemic from non-ischaemic CRVO during the early acute phase. Graefes Arch Clin Exp Oph