Effects of cataract surgery on symptoms and findings of dry eye in subjects with and without preexisting dry eye.

PURPOSE: To compare dry eye symptoms and findings in post cataract surgery eyes' with and without preexisting dry eye. STUDY DESIGN: Prospective, observational case-control study. METHODS: Sixty-seven eyes that had undergone cataract surgery were included; 48 were classified into group D (preexisting dry eye) and 19 into group N (no preexisting dry eye). No subjects received perioperative treatment for dry eye. We evaluated between-group differences in symptom scores, corrected distance visual acuity (CDVA), tear film breakup time (BUT), tear film breakup pattern (BUP), and ocular surface fluorescein staining scores, at 1 week, 1 month, and 3 months postoperatively. RESULTS: Symptoms were unchanged in group N, but improved in group D (P < .001) postoperatively. CDVA was improved after surgery in both groups (P < .001). BUT was shorter preoperatively in group D than in group N although this difference was absent 1 month postoperatively. Fluorescein staining scores significantly increased at 1 month postoperatively in group N (P = .01), but did not change in group D. During the perioperative period, the predominant BUP was the random break pattern in both groups (≥ 85%). From 1 week to 3 months, dimple break patterns decreased in group D (P = .007), whereas spot break patterns increased (P = .01). CONCLUSIONS: Cataract surgery has an influence on tear film stability and the ocular surface. There was either a transient improvement or worsening of ocular surface wettability in some patients without preexisting dry eye.

Four cases of Acanthamoeba keratitis treated with phototherapeutic keratectomy.

PURPOSE: To report 4 cases of Acanthamoeba keratitis treated with excimer laser phototherapeutic keratectomy (PTK) and to discuss the clinical efficacy of this procedure. METHODS: Four cases with early stage Acanthamoeba keratitis resistant to medical amoebic therapy for at least 1 week and with an enlarged abscess underwent PTK. RESULTS: After PTK, the infected corneal lesions were removed and the clinical symptoms rapidly resolved in all cases. Another 40-µm ablation was required as a result of the 1-week delay in performing PTK. There was no recurrence during the postoperative period. CONCLUSION: When lesions are limited to about one third of the superficial corneal stromal layer, PTK could be the most beneficial option for treating Acanthamoeba keratitis, resistant to medical amoebic therapy using chlorhexidine or polyhexamethylene biguanide, because of direct removal of resistant amoebic cysts and better visual recovery without irregular astigmatism.