[Isovolemic hemodilution in central retinal vein occlusion in patients less than 50 years of age]

The influence of anti-VEGF therapy on present day management of macular edema due to BRVO and CRVO: a longitudinal analysis on visual function, injection time interval and complications

The purpose of this study was to evaluate the impact of intravitreal bevacizumab injections on the management and outcome of patients affected by retinal vein occlusions, their effectiveness on morphological and functional parameters, the modalities of long-term management and the need for additional laser treatment due to ischemic retinal evolution. Patients diagnosed with branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO) had a comprehensive work-up including complete ophthalmic examination, fluorangiography (FA), optical coherence tomography (OCT), visual field testing (VFT), microperimetry (MP), and laser flare photometry (LFP). In case of BRVO, intraocular bevacizumab injection was performed if significant macular edema/visual deficit was still present 3 months after onset of occlusion and injections were started at presentation in case of CRVO. Post-injection follow-up examination including best corrected visual acuity (BCVA), intraocular pressure (IOP), LFP, OCT, MP, and VFT were performed monthly and recorded at the end of follow-up. Follow-up FA was performed between 12 and 18 months after diagnosis. Injections were repeated in case of recurrence of a significant central macular edema. Patients were subdivided into 2 groups according to number of injections: 1-4 injections or more than 4 injections. The proportion of resolved cases (no recurrence after a minimum follow-up of 12 months) was calculated and correlated with number of injections. In patients needing sustained injections, management modalities were recorded. The proportion of patients having needed laser photocoagulation treatment because of significant ischemic signs was recorded. Fifty-one patients were diagnosed with retinal vein occlusion between 2006 and 2012 at the Centre for Specialized Ophthalmic Care (COS) in Lausanne, Switzerland. Forty-four had enough data and were included in the study. Nine eyes were affected by CRVO and 35 were affected by BRVO. Mean BCVA at presentation was 0.24 ± 0.2 and improved to 0.81 ± 0.38 (p < 0.01) at 48 months. MP improved from 184.9 ± 92 to 362.5 ± 56.2 (p < 0.01) at 42 months follow-up. The number of injections varied from 1 to 25 (mean 5.5 ± 5.43). 31/44 eyes received 1-4 injections (group 1) of which all were recurrence free, with a follow-up of at least 1 years in all. 13/44 eyes received more than 5 injections (group 2) with functional and morphological parameters maintained in 9/13 but only 1/13 patients showed resolution. Rhythm of injection varied from one patient to another but 8/13 patients needing continuous injections had a constant time interval between injections. In 8/44 patients, laser photocoagulation had to be performed due to ischemic complications. The visual outcome using bevacizumab intravitreal injection was exceptionally good and functional parameters such as BCVA, MP, and VFT improved significantly. In about two-thirds of patients, resolution was obtained after 1-4 injections. In one-third of patients, continuous injections were necessary but a constant rhythm for re-injection for each patient could be established allowing to reduce to a minimum follow-up visits. The absence of significant side effects allowed to re-treat apparently without limitation achieving maintained visual function. FA monitoring for the detection of ischemic complications should not be neglected especially in cases where bevacizumab could be discontinued.

Medical treatment of retinal vein occlusions

The medical treatment of retinal vein occlusion (RVO) is comprised of three main stages: identification and therapy of the detectable risk factors, specific treatment aimed at the occlusive form and treatment of RVO complications. Even though the possible medical management of RVO includes several treatments, the most interesting approaches have been: anticoagulant/antiaggregating agents, troxerutin, corticosteroid, fibrinolytic/thrombolytic agents, and hemodilution. Overall, the medical approach to RVO is still awkward and unsatisfactory. Randomized clinical trials are needed to assess the degree of efficacy of the medical treatment of the specific forms of RVO.

[Treatment of central retinal vein occlusion by isovolemic hemodilution]

PURPOSE

Evaluate the effects of hemodilution in the treatment of central retinal vein occlusion (CRVO).

PATIENTS AND METHODS

We carried out a retrospective, noncomparative study of 25 patients presenting unilateral CRVO, treated with one to three hemodilution sessions. The patients were re-examined in the 1st, 2nd, 3rd, 6th and 12th months following treatment with measurement of visual acuity, fluorescein angiography, and optical coherence tomography.

RESULTS

Our study included 17 men and eight women, averaging 63 years of age (range, 35-87 years), and monitored for an average of 7 months (range, 3-12 months). After the 6th month following treatment, average visual acuity improved compared to initial visual acuity. Initial visual acuity of less than 1/10, with the existence of poorly irrigated areas in the angiography, presented negative prognosis factors. The number of hemodilutions did not produce a significant difference in final visual acuity. No serious complications due to hemodilution were observed.

DISCUSSION

Treatment of CRVO is subject to debate. Some practitioners recommend against treatment, while others advocate intervention and offer laser-induced chorioretinal venous anastomosis. Surgical vitrectomy and radial optical neurotomy, with or without injection of triamcinolone, await evaluation. Hemodilution may offer a therapeutic approach to this pathology, in which the etiopathogenesis is not yet recognized, but in which blood viscosity plays a key role. This treatment is well tolerated.

CONCLUSION

Hemodilutions appear to have beneficial effects in treating CRVO, whatever the number of hemodilutions used. This study should be confirmed by a prospective study using an untreated control group.