how does dsaek surgery can change corneal biomechanical properties in patients with pseudophakic bullous keratopathy

purpose: to compare corneal biomechanical properties and intraocular pressure (iop) in eyes with pseudophakic bullous keratopathy (pbk) before and after descemet stripping automated endothelial keratoplasty (dsaek). methods: this prospective non-randomizedintrasubject comparative study was conducted on 44eyes of 22 patients with the diagnosis ofpbk who underwent dsaek in one eye.intraocular pressure was measured by goldmannapplanation tonometer (iop gat), and central corneal thickness (cct) was measured by ultrasound pachymetry. the ocular response analyser (ora) was used to measure corneal hysteresis (ch), corneal resistance factor (crf), goldmann-related intraocular pressure (iopg), and cornea-compensated intraocular pressure (iopcc). the same measurements were performed in the normal fellow eyes which served as controls. all measurements were performed preoperatively and six months postoperatively. results: mean patient agewas 67 ± 14 years. mean preoperative ch and crfvalues in the dsaek group were 5.77 ± 2.94 and 6.39 ± 2.72 mm hg, respectively, which were significantly lower than those measured in the control group (8.2±2.47 and 8.43±2.49 mm hg, respectively, p=0.001 for both comparisons). postoperatively, ch and crf demonstrated a significant increase (7.09 ± 3.68 mm hg, p=0.05 and 8.21 ± 3.84 mm hg, p=0.03, respectively) in operated eyes approaching the normal values measured in the control eyes. conclusion: corneal biomechanicalparameters were significantly lower inpbk eyes as compared to the normal fellow eyes. these metrics significantly increased after dsaek and reached values measured in the normalfellow eyes.