Purpose:
To test Stopa’s geometrical conclusion that horizontal gaze was optimum for pneumatic displacement of a subretinal hemorrhage in the macula and gravity was the principle force acting to move the hemorrhage.
Methods:
The eyes of 9 consecutive patients with subretinal hemorrhage in the macula were give an intravitreal injection of perfluorocarbon gas (0.4cc of C3F8 or 0.5 cc of C2F6), sufficient for the expanded volume to cover the macula when the patient gazed down 40º below the horizontal. They were asked to maintain the gaze down position for 20 minutes every hour while awake.
Results:
The subretinal hemorrahge in 8 of 9 patients was displaced rapidly in the first week. Visual acuity improved in 7 patients.
Conclusions:
Gravity appeared to be the principle force acting to displace a subretinal hemorrhage in the macula. Gaze 40º below the horizontal was chosen because it diminished the amount of intraocular gas required to cover the macula and still retained 79% of the maximum gravity force tangential to the globe, that would be obtained with horizontal gaze (Fig. 1).
Keywords: clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • macula/fovea • age-related macular degeneration