Why grafts are irregular
A full thickness or deep lamellar transplant sews a donor cornea into the patient's cornea with fine sutures. Tension in the sutures, the fit of the graft to the host bed, and the healing of the junction all shape the new surface, and even a technically perfect graft commonly has several diopters of astigmatism, often irregular. Sutures are adjusted or removed over the first one to two years to reduce it, and the shape continues to change as each is removed. Endothelial grafts (DMEK, DSAEK) replace only the inner layer and cause much less irregularity; many of those patients need no specialty lens.
Why scleral lenses suit grafts
A scleral lens rests on the sclera outside the graft and vaults over it, so the lens never touches the graft, never bears on the junction or the sutures, and neutralizes the irregularity with its fluid layer. It also protects a graft with reduced sensation from drying. Rigid corneal lenses can be used on regular grafts but risk bearing on the junction, and hybrids are occasionally suitable. Soft lenses cannot correct the irregularity and are limited to mild cases.
Timing and coordination
Fitting begins only when the cornea surgeon confirms the graft is stable, usually after the sutures that will be removed have been removed and tomography has stopped changing. Fitting a lens over a graft with active suture changes wastes lenses and can stress the graft. The surgeon and the lens fitter work together: the surgeon monitors the graft's health and rejection risk; the fitter monitors the fit, the clearance and the endothelial health beneath the lens, and any sign of rejection (redness, light sensitivity or reduced vision) is referred back the same day.
Fitting and follow-up
Tomography maps the graft, and a diagnostic scleral lens is assessed for clearance over the whole graft and junction. The custom lens is refined over a few visits. Wearing time is built up gradually, and follow-up is closer than for other scleral patients because a graft's endothelium is precious: the lens's oxygen transmission and vault are chosen with that in mind. Lenses are refitted when the graft changes, which can happen years later.
Is this right for your eyes?
Nothing on this page is a diagnosis. Whether this is the right choice for you is decided by a full examination at one of our 4 offices: Pasadena, Huntington Beach, Woodland Hills and Beverly Hills.
About this content: This page was written with the assistance of AI tools and reviewed for medical accuracy by Dr. Arbi Melikian, OD. It is general information, not medical advice, and does not replace an eye examination. Individual results vary. Read our medical disclaimer.
