Predictive factors of graft detachment and rebubbling after descemet membrane endothelial keratoplasty

Preoperative Posterior Stromal Ripples as Predictive Biomarkers of Visual Recovery After DMEK

PURPOSE

To investigate the role of preoperative posterior stromal ripples (pre-PSR) on visual acuity recovery after Descemet membrane endothelial keratoplasty (DMEK).

METHODS

This is a comparative case series retrospectively analyzing patients who underwent DMEK. Electronic records and imaging of DMEK patients were reviewed. The last preoperative and first postoperative available anterior segment optical coherence tomography scans for each eye were analyzed for the presence of pre-PSR. The difference in longitudinal trends of visual acuity recovery after DMEK was assessed in eyes with and without pre-PSR. The frequency of rebubbling and measures of proportional relative risk of rebubbling were analyzed according to the presence of preoperative and postoperative PSR.

RESULTS

A total of 66 patients (71 eyes) were included. Pre-PSR were associated with lower preoperative visual acuity [0.6 (0.5) vs. 0.9 (0.6) LogMAR, P = 0.02] and higher central corneal thickness [613 (73.8) vs. 715.7 (129.6) micron, P < 0.001]. Eyes with pre-PSR had a slower visual recovery up to 3.5 months after surgery compared to eyes without pre-PSR and achieved lower final visual acuity [0.1 (0.2) vs. 0.3 (0.3) LogMAR, P = 0.02]. Cox proportional hazard ratios showed that postoperative PSR were associated with a greater risk of rebubbling [hazard ratio (95% CI), 7.1 (1.3, 39.5), P = 0.02] while pre-PSR were not.

CONCLUSIONS

The presence of pre-PSR is associated with slower visual recovery and lower final visual acuity after DMEK while postoperative PSR confer a higher risk of rebubbling. PSR represent a valuable prognostic biomarker both before and after DMEK.

Effects of graft detachment on the central corneal thickness after uncomplicated Descemet membrane endothelial keratoplasty

PURPOSE

To determine if early central corneal thickness (CCT) and best-corrected visual acuity (BCVA) changes indicate graft detachment after uncomplicated Descemet membrane endothelial keratoplasty (DMEK).

METHODS

In this analysis of our prospectively collected ADDA registry data ( https://drks.de/search/de/trial/DRKS00027180 ), 45 pseudophakic eyes underwent DMEK surgery at the Department of Ophthalmology, RWTH Aachen University. Anterior segment optical coherence tomography (AS-OCT), the presence of stromal ripples on the posterior corneal surface, and BCVA measurements were assessed prior to, 1 day, 1 week, 1 month, and 6 months after surgery.

RESULTS

Eyes were categorized into three groups: no graft detachment (group 1) (20/45; 44.4%), < 1/3 graft detachment (group 2) (14/45; 31.1%), ≥ 1/3 graft detachment followed by rebubbling (group 3) (11/45; 24.4%). Eyes in group 3 had a greater CCT prior to (746.8 ± 95.8 µm vs. 665.0 ± 74.4 µm, P = 0.041), and 1 week (666.8 ± 119.5 µm vs. 556.5 ± 56.8 µm, P = 0.001) after DMEK compared to group 1. By 1 month, CCT in all groups aligned. Comparing prior to and 1 week after DMEK, none of the eyes in group 1 had an increase in CCT, while the CCT increased in 25.0% of eyes in group 2 and 22.2% in group 3. In group 1, 90.0% had a CCT of < 600 µm 1 week after DMEK, compared to only 50.0% in group 2 and 36.4% in group 3. In group 1, 90.0% (18/20) had an improved BCVA 1 week after DMEK, while in groups 2 and 3, 86.7% (12/14) and 18.2% (2/11) improved, respectively. One patient in group 3 showed posterior stromal ripples 1 day and 1 week after DMEK.

CONCLUSION

If 1 week after uncomplicated DMEK CCT is < 600 µm and has decreased from before surgery, BCVA has improved, and there are no posterior stromal ripples, a graft detachment ≥ 1/3 and the need for rebubbling are very unlikely. In all other cases, meticulous slit-lamp and OCT inspection of the peripheral graft for detachments should be advised.

Predictive factors for re-bubbling after DMEK: focus on the posterior corneal surface

PURPOSE

To understand whether the preoperative morphology of the posterior corneal surface influences the rate of re-bubbling after Descemet membrane endothelial keratoplasty (DMEK).

METHODS

After retrospectively analyzing the medical records of patients undergoing DMEK, in this multicentric cross-sectional study, we performed a binomial logistic regression analysis to assess significant predictors of re-bubbling and re-transplantation after surgery. Analyzed parameters included the preoperative diagnosis, anterior and posterior surface K1/K2, central corneal thickness, posterior Q value, and other posterior corneal surface parameters evaluated on the elevation maps produced by anterior segment optical coherence tomography. Results were stratified based on the surgeons' experience.

RESULTS

We included 202 eyes of 202 patients with a mean age of 69.5 ± 12.4 years; 154 eyes were operated by a high-volume surgeon and 48 by one with less experience; 48 eyes (23.8%) underwent ≥ 1 re-bubbling and 14(6.9%) ≥ 1 re-transplantation. The presence of positive/less-negative posterior corneal irregularities and irregularities with greater absolute height had a significantly higher risk of re-bubbling in both the expert and less expert group (OR = 2.85 and 1.42, OR = 3.22 and 3.01, respectively, p < 0.05), whereas more negative posterior K1 and K2 were significant risk factors only in the former group (OR = 0.67 and 0.55, respectively, p < 0.05). Endothelial decompensation other than Fuchs and pseudophakic bullous keratopathy, more negative posterior Q values and smaller distances between center, and the highest/lowest posterior corneal surface irregularity correlated with an increased risk of graft failure (OR 1.23, 1.21, and 1.29, respectively, p < 0.05).

CONCLUSION

Posterior corneal surface morphology significantly influences the risk of re-bubbling after DMEK.

Safety and clinical outcomes of omitting same and next day review after DMEK performed with an inferior peripheral iridotomy

BACKGROUND/OBJECTIVES

To determine the incidence of day one postoperative complications after Descemet Membrane Endothelial Keratoplasty (DMEK) performed with intraoperative inferior peripheral iridotomy (PI), and whether their early detection influences postoperative intervention.

SUBJECTS/METHODS

70 eyes of 70 consecutive patients that underwent DMEK from August 2019 to August 2021 at a single UK centre were retrospectively analysed. Cases that did not have an inferior PI were excluded. Any action taken at day one and week one postoperative review was noted.

RESULTS

No pupil block or other major adverse events were found at day one review. At one week, 14 eyes (20%) required re-bubbling, all of which had been fully attached at the day one review.

CONCLUSIONS

This series suggests that inferior PI performed alongside DMEK alone or triple DMEK effectively minimizes the risk of pupil block. Since no early complications occurred in this cohort requiring immediate intervention, it may be safe to defer review of these patients to a later time point.