William Power

Patient pain during different stages of phacoemulsification using topical anesthesia.

Purpose: To assess the pain experienced by patients during the different stages of phacoemulsification cataract surgery performed under topical anesthesia. Setting: Ophthalmic teaching hospital, Dublin, Ireland. Methods: This prospective study comprised 100 consecutive patients having phacoemulsification under topical anesthesia. Patients were asked to grade the pain they experienced during the different stages of the procedure using a visual analog pain scale from 0 to 10. The pain experienced during the procedure was compared with that experienced after the instillation of a drop of amethocaine. Results: The overall mean pain score was 1.46. The highest mean pain score, which was during the phacoemulsification stage of the procedure, was not significantly more than the score for the administration of the topical anesthetic agent. The duration of surgery was not related to the level of pain during the procedure. Conclusions: Topical anesthesia was effective in phacoemulsification cataract surgery. Because the highest mean score was not significantly higher than that for the administration of the anesthetic agent, it is possible to counsel patients before surgery that the pain they experience during the procedure will be no worse than that during administration of the anesthetic drops.

Acyclovir ointment plus topical betamethasone or placebo in first episode disciform keratitis.

Thirty patients with first episode disciform keratitis and with no previous steroid exposure were randomly assigned to double blind treatment with 3% acyclovir ointment and 0.1% betamethasone (Betnesol) drops or acyclovir ointment and matching placebo. In the steroid group 14 of the 15 patients healed in a mean time of 21.8 days. In the placebo group eight of the 13 patients healed in a mean time of 34.5 days. The difference in mean healing time between the two groups was significant (p < 0.05). The cumulative rate of healing was also quicker in the steroid group when compared with the placebo group (p < 0.001). Other clinical parameters improved more favourably in the combination treatment group. Four patients, two in either group, experienced a mild transient punctate epitheliopathy, but no other serious adverse effects were noted. There has been no significant difference in the recurrence rate between the two groups after a mean follow-up period of approximately 3 years.

Randomised double-blind trial of bromovinyldeoxyuridine (BVDU) and trifluorothymidine (TFT) in dendritic corneal ulceration.

The results of a randomised double-blind clinical trial of 0.1% bromovinyldeoxyuridine (BVDU) and 1% trifluorothymidine (TFT) in 60 patients with corneal dendritic ulceration are presented. There was no significant difference between BVDU and TFT in terms of numbers of ulcers healed (p = 0.61), mean healing time (p = 0.065), and cumulative healing rate (p = 0.058). No serious side effects were observed, though transient stinging was recorded in five patients receiving TFT and in three patients receiving BVDU. One patient in the group treated with TFT developed a punctate epitheliopathy.

Adherence of human lens epithelial cells to conventional poly(methyl methacrylate), heparin-surface-modified, and polyHema lenses

Abstract We developed an in vitro model to assess the adherence of human lens epithelial cells to three types of intraocular lenses: poly(methyl methacrylate) (PMMA), heparin‐surface‐modified PMMA (HSM‐PMMA), and polyHema. Lenses were incubated with a fixed number of human lens epithelial cells. Adherent cells were counted after 72 hours in culture. Scanning electron microscopy showed significantly fewer cells adhering to the HSM‐PMMA and polyHema lenses than to the PMMA lenses (P <.01). Repeat experiments on cell lines established from different donors confirmed these findings.

Growth characteristics of human lens epithelial cells in culture: effect of media and donor age

The effect of different concentrations of fetal calf serum (FCS) on the proliferative capacity of human and bovine lens epithelial cells in culture was evaluated. The effect of donor age on the maximum number of passages achieved using thirty eight individual cultures was also studied. The donor ages ranged from 1–88 years. Fifteen percent FCS was found to be the optimum concentration for both human and bovine cells. The two cell types demonstrated very similar responses across the spectrum of concentrations used. Correlation analysis revealed a significant (p < 0.05) negative correlation between donor age and maximum number of cell passages achieved.

Corneal inlay implantation complicated by infectious keratitis

Background/aims To report five cases of infectious keratitis following corneal inlay implantation for the surgical correction of presbyopia. Methods This was a retrospective, observational case series. Five eyes of five patients were identified consecutively in two emergency departments during a 1-year period, from November 2013 to November 2014. Patients’ demographics, clinical features, treatment and outcomes are described. Results There were four female patients and one male, aged 52–64 years. Three patients had the KAMRA inlay (AcuFocus) and two had the Flexivue Microlens inlay (Presbia Coöperatief U.A.) inserted for the treatment of presbyopia and they presented from 6 days to 4 months postoperatively. Presenting uncorrected vision ranged from 6/38 to counting fingers. One patients corneal scrapings were positive for a putatively causative organism, Corynebacterium pseudodiphtheriticum, and all patients responded to broad-spectrum fortified topical antibiotics. All patients lost vision with final uncorrected visual acuity ranging from 6/12 to 6/60 and best-corrected vision ranging from 6/7.5 to 6/12. Two patients’ corneal inlays were explanted and three remained in situ at last follow-up. Conclusions Infectious keratitis can occur at an early or late stage following corneal inlay implantation. Final visual acuity can be limited by stromal scarring; in the cases where the infiltrate was small and off the visual axis at the time of presentation, the final visual acuity was better than those patients who presented with larger lesions affecting the visual axis. Though infection may necessitate removal of the inlay, early positive response to treatment may enable the inlay to be left in situ.

The role of common viral ocular pathogens in Thygeson’s superficial punctate keratitis

Background/aims: The aetiology of Thygeson’s superficial punctate keratitis (TSPK) remains elusive. A viral aetiology has been suggested by the absence of bacterial infection and clinical resemblance to other viral keratopathies. We report the results of polymerase chain reaction analysis for the detection of herpes simplex virus (HSV) 1 and 2, herpes zoster virus, varicella zoster virus (VZV) and adenovirus from corneal epithelial samples from patients with active signs and symptoms of TSPK. Methods: Schirmer strip impressions were taken from the epithelium of eight patients with a known history of TSPK and symptoms and signs of active disease. Three patients were recruited as positive controls (two with herpes simplex keratitis and one with herpes zoster ophthalmicus). Samples from a further three patients acted as negative controls. All 14 samples underwent polymerase chain reaction testing for HSV 1, HSV 2, VZV and adenovirus. Results: DNA corresponding to the expected viral DNA was amplified from all three positive control samples. The three negative control samples showed no evidence of viral DNA. Similarly, all samples from patients with TSPK showed no evidence of the presence of HSV 1, HSV 2, VZV or adenovirus. Conclusion: We conclude that HSV, VZV and adenovirus are not present in the epithelium of patients with TSPK. These results are considered in light of existing theories regarding the aetiology and treatment of this condition.

Patient pain during stretching of small pupils in phacoemulsification performed using topical anesthesia

PURPOSE: To assess the pain experienced by patients with small pupils during pupil stretching in phacoemulsification performed using topical anesthesia. SETTING: Royal Victoria Eye & Ear Hospital and Mater Misericordiae University Hospital, Dublin, Ireland. METHODS: This was a prospective study that included 26 eyes with small pupils requiring mechanical pupil stretching during phacoemulsification cataract surgery performed under topical anesthesia without sedation. RESULTS: The mean pain score for the instillation of anesthetic drops (2.02) was higher than the mean pain score for the pupil stretch (1.63), but this difference was not significant (signed rank test = −32; P = .2738). There was no significant correlation between the duration of surgery and the overall pain score (r = 0.345; P = .08). There was no significant correlation between change in pupil size and either the pupil stretch score (r = −0.069; P = .74) or the overall pain score (r = −0.032; P = .8739). CONCLUSIONS: Pupil stretching during phacoemulsification in patients with small pupils was performed with minimal patient‐reported pain using topical anesthesia. Stretching small pupils with a mechanical device during phacoemulsification performed under topical anesthesia was a safe procedure and did not result in significant patient discomfort.

Morphological appearances of human lens epithelial cells in culture

A system for culturing human lens epithelial cells in the laboratory was developed. The morphological appearances of the cells was studied using phase contrast, scanning and transmission electron microscopy. Cell marker studies using monoclonal antibodies to cyto-keratin, vimentin and epithelial membrane antigen were also performed. There was a marked increase in cell size as a function of time in culture. After 3 to 4 weeks cells showed early signs of ageing. By 6 to 8 weeks the majority of the cells had become very irregular in shape and demonstrated irregularities of the plasma membrane and intra-cytoplasmic vacuole formation. The cells stained strongly for vimentin and epithelial membrane antigen. Staining with cytokeratin was somewhat weaker. This culture technique provides us with a suitable model for studying the growth behavior of these cells.

The current management of herpetic eye disease

Herpes simplex disciform keratitis is a difficult condition. The general feeling is that it is an immune disease, mediated by the virus, possibly located in the endothelial cells. It is frequently combined with inflammation in the trabecular meshwork and with uveitis. There is some controversy in relation to treatment and it has been suggested that anti-virals will control herpetic disciform keratitis, particularly if the patient has never had steroids previously. The authors of this paper have, in the past, published data which showed that Acyclovir, with corticosteroid, was necessary in the management of disciform keratitis. The data suggested that Acyclovir on its own was not effective. It remained to be answered whether Acyclovir on its own would be effective in patients who never had steroids for any reason previously. This paper demonstrates clearly that it is necessary, irrespective of whether patients have had steroids in the past or not, to combine corticosteroids with Acyclovir in the management of herpetic disciform keratitis. Acyclovir, on its own, is shown to be ineffective. It has also been suggested that Acyclovir is non-toxic. In a general way this is true, but the authors suggest that Acyclovir ointment does produce a punctate keratitis in patients with tear film disease, and that oral Acyclovir is preferable in such patients.