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Published on: June 3, 2021
Analysis of forces acting upon submacular hemorrhage in pneumatic displacement
Marcin Stopa1, Andrew Lincoff, Harvey Lincoff
1Duke University Eye Center, Durham, North Carolina, USA.
Purpose:
To analyze the forces affecting pneumatic displacement of submacular hemorrhage and determine an efficient postoperative positioning method for patients.
Method:
Geometric analysis of the forces that act upon submacular hemorrhage in the absence and presence of a gas bubble.
Results:
A component of gravity force of the hemorrhage parallel to the subretinal space is responsible for pneumatic displacement. This component is largest when the patient is looking straightforward and is absent when the patient is positioned facedown.
Conclusion:
Face down positioning is not optimal for pneumatic displacement of submacular hemorrhage and should be avoided.

