To outline the mechanism of closure in macular hole surgery: specifically the importance of deforming the fluid-air interface at the edges of the macular hole. This will provide a basis for understanding of how vitrectomy effects macular hole closure. Successful macular hole closure occurs when a fluid interface contacts, and is deformed, by the edges of the hole; generating a “surface of tension” (force), which exceeds the “stiffness” of the retina, allowing for reapproximation of the hole edges along the inner retina. Mechanical barriers, such as posterior hyaloid or vitreous, may reduce the interface deformation and transmittal of these forces to the inner retinal surface; peeling ILM or manipulating the hole edge may reduce the “stiffness” of the retina requiring less force to achieve closure. Larger bubbles increase the macular hole interface contact angle creating interface deformation, and force generation, at the hole edge over a greater range of eye position.Conclusion:
Macular holes close by a “bridging” along the inner retinal surface with migration assisted by the capillary forces generated by fluid-air interface deformation at the edges of the macular hole.