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A 40 degrees gaze down position for pneumatic displacement of submacular hemorrhage: clinical application and results
Harvey Lincoff1, Ingrid Kreissig, Marcin Stopa
1Department of Ophthalmology, New York Presbyterian Hospital, Weill Medical College of Cornell University, New York, USA.
Purpose:
To test the validity of the geometric conclusion that 40 degrees gaze down is optimal for pneumatic displacement of a subretinal hemorrhage (SRH) in the macula.
Methods:
Nine consecutive patients with SRH in the macula had an intravitreal injection of perfluorocarbon gas sufficient to cover the macula when the patient gazed down 40 degrees below the horizontal. They were asked to maintain the gaze down position for 20 minutes every hour while awake.
Results:
The SRH in eight of nine patients was displaced rapidly in the first week. Visual acuity improved in seven patients. Visual recovery was limited by the presence of a subpigment epithelial component.
Conclusions:
Gaze 40 degrees below the horizontal will rapidly displace a subretinal hemorrhage that is covered by a gas bubble.

