Clinical Studies:

BVOS Study: Part 2 (Neovascularization and Vitreous Hemorrhage)

Summarized by Prethy Rao, MD MPH (Retina and Vitreous of Texas)

Citations: BVOS Group. Argon laser scatter coagulation ifor prevention of neovascularization and vitreous hemorrhage in branch vein occlusion. Arch Ophthalmol 1986;104:34-41

  • Objective:

    To study the safety and efficacy of argon laser photocoagulation in the treatment of BRVO with macular edema in patients with a visual acuity of 20/40 or worse, prevention of neovascularization, and prevention of vitreous hemorrhage

  • STUDY DESIGN:

    Multicenter, randomized, controlled trial


STUDY SUBJECTS

Major Inclusion Criteria for Group 1, 2, X

Group I


Group II


Group X (this group was NOT randomized)


RANDOMIZATION SCHEME AND INTERVENTIONS

Randomized 1:1

  1. (a) Scatter argon laser photocoagulation
  2. (b) No laser photocoagulation

Method of Scattered Laser: FA and fundus photography guided laser over area of involvement (200um-500 um spot size, 1 burn width apart) and no closer than 2 DD from the foveal center.


**Note: Early on in study, if Group II controls with neovascularization developed vitreous hemorrhage, they were treated as it was considered not ethical not to treat after vitreous hemorrhage appeared. Later on (after determining VH might not influence long term VA), laser treatment was withheld in the control group II if VH developed

Patients were followed q 4 months with visual acuity, ophthalmic examinations, and fundus photographs performed at each visits. FA was performed at initial and annual visits.


Study Duration: July 1st, 1977 to February 28th, 1984


PRIMARY ENDPOINT:


RESULTS

Study population


PRIMARY OUTCOME:

1) Presence of Neovascularization (NV) in Group I (BRVO of at least 5 DD)

2) Presence of Vitreous Hemorrhage (VH) in Group II (BRVO with existing NVD/NVE)


NOTABLE SECONDARY OUTCOMES


Adverse events


CONCLUSION