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From the Research
Causes of Scleral Edema
- Scleral lens-induced corneal edema can be caused by various factors, including the magnitude and regional variation in corneal edema after scleral lens wear 1, 2, 3
- Post-penetrating keratoplasty eyes exhibit significant corneal edema after lens wear, with a greater magnitude of corneal edema and greater variability in the corneal response compared to healthy eyes 3
- Scleral lens wear may exacerbate edema in patients who have undergone penetrating keratoplasty, particularly if lens fit is suboptimal 4
- Ciliary body edema can occur after scleral buckling surgery for rhegmatogenous retinal detachment, with significant increases in ciliary body thickness at 3,7, and 14 days postoperatively 5
Factors Contributing to Scleral Edema
- Fluid reservoir thickness can contribute to scleral lens-induced corneal edema, with greater stromal oedema observed for medium and high fluid reservoir thickness conditions compared to low conditions 2
- Lens design and fitting factors, such as hypoxic and mechanical corneal stress, should be carefully considered for all post-penetrating keratoplasty scleral lens fits to minimize potential graft rejection or failure in the longer-term 3
- The direction of scleral buckling can affect the magnitude of ciliary body edema, with greater edema observed in the direction of buckling than on the opposite side 5