Effect of the shape of the endothelial graft on the refractive results after Descemet's stripping with automated endothelial keratoplasty

Refractive change and stability after Descemet membrane endothelial keratoplasty

“…Second, a triple procedure might be avoided because using an ophthalmic viscosurgical device during the procedure may increase the risk for endothelial graft detachment. 13 A hyperopic shift was also found with subjective refraction. From preoperatively to 6 months postoperatively, there was a mean increase in SE of approximately C0.30 D and in cylindrical error of approximately À0.50 D; both changes were statistically significant.…”

“…[5][6][7][8][9] Furthermore, nonuniform graft thickness in DSAEK has been correlated with a refractive shift of approximately C1.50 diopters (D). [10][11][12][13][14][15][16][17][18] To overcome these problems, we recently introduced a technique for the selective transplantation of a donor Descemet membrane, now referred to as Descemet membrane endothelial keratoplasty (DMEK). This technique provides near normal visual recovery.…”

“…It has been suggested that a hyperopic shift of C1.00 to C2.00 D can occur because a microkeratome-dissected posterior transplant is thicker in the periphery than in the center; therefore, the donor tissue may act as a negative lenticule. [10][11][12][13][14][15][16][17] The key difference with DMEK is that DSEK and DSAEK grafts contain a layer of donor posterior stroma, whereas in DMEK only a donor Descemet membrane with its endothelium is transplanted. Because DMEK is essentially a procedure in which no tissue is added (the donor Descemet graft merely replaces the recipient Descemet membrane that is stripped off during descemetorhexis), our study may enable a more refined analysis of the cause of such secondary refractive changes.…”

Endothelial Keratoplasty: Past, Present, and Future Directions

“…The DSAEK lenticule is thinner centrally than peripherally and this negative lenticule, when added to the posterior surface, results in a focal point that is more posterior than the original corneal power, creating a ''hyperopic shift.'' [54][55][56][57] It is important to take this expected hyperopic shift into account when carrying out concurrent cataract surgery and to choose an IOL of the appropriate power to correct for this expected hyperopic shift. In contrast to the expected shifts in spherical corneal power, the change in astigmatic error is minimal with a mean change of 0.11D and a range of 0.4 to 0.6 D, even when a 5-mm scleral-limbal wound is used.…”

Graft profile and thickness as a function of cut transition speed in Descemet-stripping automated endothelial keratoplasty

“…Insertion of a corneal lenticule acts as an additional lens and creates a new optical interface. Postoperative imaging studies suggest that variations in the ratio of central to peripheral graft thickness produce a hyperopic refractive shift in many patients [2][3][4] and that posterior corneal astigmatism is increased relative to that in unoperated eyes. 5,6 Anterior segment optical coherence tomography (AS-OCT) has been validated as an accurate, fast noncontact method for performing regional corneal pachymetry.…”