Corneal changes following short-term miniscleral contact lens wear

To examine the influence of short-term miniscleral contact lens wear on corneal shape, thickness and anterior surface aberrations.

Scheimpflug imaging was captured before, immediately following and 3h after a short period (3h) of miniscleral contact lens wear for 10 young (mean 27±5 years), healthy participants. Natural diurnal variations were considered by measuring baseline diurnal changes obtained on a separate control day without contact lens wear.

Small but significant anterior corneal flattening was observed immediately following lens removal (overall mean 0.02±0.03mm, p<0.001) which returned to baseline levels 3h after lens removal. During the 3h recovery period significant corneal thinning (-13.4±10.5μm) and posterior surface flattening (0.03±0.02mm) were also observed (both p<0.01). The magnitude of posterior corneal flattening during recovery correlated with the amount of corneal thinning (r=0.69, p=0.03). Central corneal clearance (maximum tear reservoir depth) was not associated with corneal swelling following lens removal (r=-0.24, p>0.05). An increase in lower-order corneal astigmatism Z(2,2) was also observed following lens wear (mean -0.144±0.075μm, p=0.02).

Flattening of the anterior corneal surface was observed immediately following lens wear, while 'rebound' thinning and flattening of the posterior surface was evident following the recovery period. Modern miniscleral contact lenses that vault the cornea may slightly influence corneal shape and power but do not induce clinically significant corneal oedema during short-term wear.