Macular holes viewed objectively
Idiopathic full thickness macular holes (FTMH) are an important cause of poor vision in the elderly. Decreased visual function is mainly due to the absence of photoreceptors within the central retinal defect. Also, the adjacent cuff of subretinal fluid and secondary retinal elevation cause a relative scotoma surrounding the absolute central field defect.
The recent observation of Gass on the pathogenesis of FTMH1 has sparked a number of investigations into new methods of assessment of FTMH. He described the vital importance of tangential vitreoretinal traction in the development and subsequent enlargement of FTMH and proposed a classification based on ophthalmoscopic signs.1 In stage 1 (impending) macular hole, the vitreoretinal traction causes foveal detachment which may progress to a small full thickness retinal defect (stage 2 FTMH). Stage 3 FTMH is usually larger and is associated with a cuff of subretinal fluid and focal vitreous detachment over the macula. In stage 4 there is complete vitreous separation. The interpretation of such signs depends on the diagnostic skills of the observer and is limited by the optical resolution of our current biomicroscopic methods. The need for improved diagnosis of such minute pathological changes has …
