Abstract
Purpose: :
the aims of this study are to evaluate the modifications of ocular surface after cataract surgery and to investigate the effect of post-surgical therapy on ocular surface signs and symptoms.
Methods: :
Forty patients (40 eyes) undegoing cataract surgery received either: (i) antibiotic-steroid eye drops (Netylmicin 0.3% and dexamethazone 0.1%; Netildex®, Sifi) containing benzalkonium chloride (BAK 0,0005%)or (ii) the same therapeutic association without BAK (Netildex® monodose, Sifi), for 1 month. Signs, symptoms, conjunctival and corneal staining, tear break-up time (BUT), Schirmer I test, and corneal sensitivity (by Cochet-Bonnet aesthesiometer) were evaluated before and 1, 7, 30, 90 days after surgery. Quality of Life and dry eye symptoms were investigated by using a 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ25) and Ocular Surface Disease Index (OSDI) 3 days before and 1 week, 1 month, and 3 months after surgery. At the same follow-up visits, 4 conjunctival impression cytology samples were also collected to evaluate conjunctival goblet cell density (by PAS staining) and MUC5AC mRNA expression (by Real-Time PCR).
Results: :
Of the 20 patients that completed follow-up, 44% complained of ocular discomfort symptoms and showed increased OSDI (18±12 at baseline vs 22±13 at week 1) and Oxford score (2±1,6 at baseline vs 3,1±1,6 at day 1), associated with decreased BUT (5,5±2,1 at baseline vs 2,8±1,3 at week 1) and conjunctival goblet cells density (28±17,5 at baseline vs 15,7±8 at 3 months). No significant changes in Schirmer test, corneal sensitivity and MUC5AC expression were observed.Patients treated with eye drops containing BAK, but not patients treated with preservative-free eye drops, had a significant (p<0.05) increase in Oxford score (2,2±2,3 at baseline vs 3±1,4 at day 1) and in MUC5AC mRNA expression (2,5±1,1 at baseline vs 1,2±2,4 at week 1), associated with a decreased BUT (5,6±2,5 at baseline vs 2,2±1,1 at week 1) and conjunctival goblet cells density (29±12,9 at baseline vs 16,6±10,8 at 3 months).
Conclusions: :
Our data show that ocular discomfort symptoms after cataract surgery are common. Changes of the ocular surface observed in this study suggest that post-surgical therapy with eye drop preservatives may cause evaporative dry eye.