Treatment of bullous keratopathy with corneal collagen cross-linking in two dogs

OBJECTIVE

Corneal collagen cross-linking with riboflavin and UV-A (CXL) decreases corneal oedema and increases visual acuity in human patients with bullous keratopathy. Presumed mechanisms are an increase in collagen packing density and a reduction in stromal swelling pressure. We present two cases in which CXL was used to treat bullous keratopathy in dogs.

PROCEDURES

Four eyes of two dogs with painful bullous keratopathy-induced corneal erosions that were resistant to prior therapy were treated with CXL. Both corneas of the second patient were dehydrated to ± 400 μm corneal thickness using topical 70% glycerol solution immediately prior to CXL. Follow-up included slit-lamp examination, fluorescein staining and photographic documentation in both cases and high-resolution ultrasound examination in the second patient.

RESULTS

All four eyes were comfortable and fluorescein negative at 1-week post-CXL and remained so for the rest of the follow-up period (17.5 months for case 1 and 6 months for case 2). The owner of the first patient reported a less oedematous cornea and improvement in vision that lasted for 6 months. Despite a reported lack of improvement in vision in the second patient, corneal thickness initially decreased, but was back at baseline thickness at the 4-month recheck.

CONCLUSIONS

Similar to humans, CXL might become a useful treatment option for bullous keratopathy-induced therapy-resistant corneal erosions in dogs. Patient comfort was greatly improved, but corneal thickness decrease was not as long-lasting as reported for humans. The presently used protocols might need modification to fit the dog cornea.

Risk Factors for Corneal Endothelial Decompensation after Penetrating Keratoplasty: A Population-Based Cohort Study

(1) Background: Endothelial decompensation is a common complication after penetrating keratopathy (PK), while the risk factors for endothelial decompensation after PK have not been fully elucidated. Consequently, we aim to investigate the possible risk factors for endothelial decompensation after PK. (2) Methods: This retrospective study was conducted using the National Health Insurance Research Database (NHIRD) of Taiwan. The main outcome was the development of endothelial decompensation after PK surgery. The effects of potential risk factors were compared between the patients with endothelial decompensation and the patients without endothelial decompensation via Cox proportional hazard regression, which produced the adjusted hazard ratio (aHR) and a 95% confidence interval (CI). (3) Results: Overall, 54 patients developed endothelial decompensation after PK surgery, with a ratio of 16.12 percent. The pre-existing type 2 diabetes mellitus (T2DM) (aHR: 1.924, 95% CI: 1.257-2.533, p = 0.0095) and history of cataract surgery (aHR: 1.687, 95% CI: 1.328-2.440, p = 0.0026) were correlated with the development of endothelial decompensation. In the subgroup analysis, the correlation between a history of cataract surgery and post-PK endothelial decompensation was more prominent in patients older than 60 years compared to their younger counterparts (p = 0.0038). (4) Conclusions: Pre-existing T2DM and a history of cataract surgery are associated with a higher incidence of post-PK endothelial decompensation.

Anterior chamber intraocular lens removal combined with triple DMEK: Quadruple DMEK for bullous keratopathy

PURPOSE

To present the outcomes of a patient with anterior chamber intraocular lens (ACIOL) related endothelial decompensation who underwent Descemet membrane endothelial keratoplasty (DMEK) and cataract surgery with intraocular lens (IOL) implantation in the capsular bag (so-called triple DMEK) combined with ACIOL removal (quadruple DMEK) in both eyes.

METHODS

Case report.

RESULTS

A 58-year-old female patient was referred due to decreased visual acuity within the last 18 months. She had a history of iris-claw ACIOL implantation 17 years before. The corrected distance visual acuity (CDVA) was 20/40 in both eyes. Due to low endothelial cell density and increased corneal thickness, ACIOL removal combined with triple DMEK (as quadruple DMEK) was performed for both eyes. Despite a graft detachment that was successfully managed with re-bubbling in the first eye, both eyes showed an increase in the CDVA (20/25 and 20/32, respectively) without any other significant complications in the follow-up of the patient. The corneas of both eyes were clear postoperatively.

CONCLUSION

This case report demonstrated that quadruple DMEK may provide feasible management for chronic endothelial cell decompensation secondary to iris-claw ACIOL implantation.