Corneal cross-linking (CXL) as a therapeutic modality in painful bullous keratopathy
Ioannis Kollias: S:t Erik Eye Hospital, Stockholm, Sweden
Supervisor: Dr. Branka Samolov MD, PhD: Cornea Section, S:t Erik Eye Hospital, Stockholm, Sweden
ABSTRACT
Purpose: To evaluate the effect of collagen cross-linking on pain in patients with bullous keratopathy (BK).
Methods: Retrospective study of all patients with the diagnosis of BK, corneal edema or endothelial dystrophy that underwent corneal cross-linking at S: t Erik Eye Hospital, Stockholm, Sweden, during 2010-2013.The patient assessment also included data on gender,age, additional eye disease and treatments, topical ocular therapy before and after the cross-linking, visual acuity, intraocular pressure (IOP), bandage contact lens before and after the cross-linking,occurrence of infectious keratitis and number of visits to the clinic during the study period. The use of bandage lens served as the surrogate variable for persistent pain.
Results: The study population included 32 patients. Twenty-one patients (67%) used bandage contact lenses for a pain relief at some point during 2010-2013. Fourteen patients (44%) used bandage lens before corneal cross-linking and 5 patients (16%) received it after one corneal cross-linking. The treatment was performed twice in 11 patients (34%), of whom 2 (0,2%) still needed the lens afterword.
Painful corneal decompensation was more common in women (69%) than men (31%) in this study population. Mean age at the time for corneal cross-linking was 76 years. Seventeen patients (53%) suffered from glaucoma, of whom 2 required trabeculectomy (11%) and 7 cyclodiode laser treatment (41%). Six of patients (19%) developed infectiouskeratitis. Four (13%) were due to bacteria, 2 of whom occurred after the cross-linking and 2 unrelated to the treatment, but in patients using bandage lenses. One patient suffered from Herpes simplex keratitis (3%) and one of fungal keratitis (3%). Four patients(13%) underwent evisceration due to corneal perforation or painful blind eye with uncontrolled IOP. Endothelial keratoplasty was performed in 5 patients (16%) with pain relief as a primary indication. All patients suffered of severe vision impairment, with mean best corrected visual acuity (BCVA) < 0, 1before and after the cross-linking. The mean number of visits to the clinic during the study period was 27 (5-81)
Conclusion:Advancedbullous keratopathy in eyes with poor vision potential is a common cause of impaired life quality due to chronic pain, frequent medical visits and risk for severe complications that even can lead to evisceration. Uncontrolled IOP represents a negative predictor. Bandage contact lens offers often a pain relief but requires professional assistance for majority of this elderly patients and is associated with risk for infection. In this study group corneal cross-linking halved the need for bandage lens during the period of three years. None the less also cross-linking was associated with complications, so as the risk for secondary infectious keratitis.