The use of the same size host and donor trephine in penetrating keratoplasty for keratoconus.

The results of a retrospective analysis of 49 eyes (40 patients) that underwent penetrating keratoplasty for keratoconus are presented. All grafts had the same size trephine for both host and donor corneas. Ninety-eight per cent of eyes achieved a post-operative visual acuity of 6/12 or better; 43% of eyes attained this level of acuity unaided, although more than half of these required spectacles or contact lenses to reach their best corrected acuity. The average post-operative spherical ametropia was -0.5 dioptre (SD 2.97 dioptres) and the average post-operative cylinder was -3.8 dioptres (SD 2.63 dioptres). Three eyes (6%) required keratorefractive surgery to reduce astigmatism. Wound integrity was satisfactory using the same (size) trephine for both host and donor, with no patient suffering a post-operative wound leak or iris prolapse. The reduction of post-operative myopia and astigmatism is discussed.

Decentration of the posterior chamber lens implant: the effect of optic size on the incidence of visual aberrations.

Intraocular lens implant components such as dialling holes can cause disabling symptoms when decentration of the implant places these components in the pupil. In order to investigate the importance of optic size in this context, we studied two groups of consecutive patients who had undergone cataract surgery: one group had received an implant with a 6 mm diameter optic, and the other an implant with a 7 mm diameter optic. We found that there was a significantly higher incidence of implant components such as dialling holes in the pupil in the 6 mm group when compared to the 7 mm group. The incidence of symptoms such as monocular diplopia and glare was marginally but not significantly higher in the 6 mm group. To minimise the risks of symptoms related to dialling holes in the pupil we recommend an implant design that has a large optical clear zone of at least 6 mm.

Primary gelatinous drop-like keratopathy.

This paper describes three siblings, the only affected members of the family, with gelatinous drop-like keratopathy. This rare form of primary corneal amyloidosis has been reported almost exclusively in Japanese literature, and to our knowledge this is the first report of the condition seen in the United Kingdom. Clinical and histological details are presented. The nature and possible aetiology of the amyloid deposits are discussed and the literature is fully reviewed.

Spontaneous intracorneal haemorrhage.

We describe the unusual complication of spontaneous intracorneal haemorrhage in a patient who used an extended-wear contact lens. This was severe enough to cause corneal blood staining and ulceration which required surgical intervention.

Rotational autokeratoplasty.

The results of sixteen patients who had undergone ipsilateral rotational autokeratoplasty are presented. Thirteen patients obtained significant visual improvement, and eight patients achieved an acuity of 6/12 or better. There were no significant pre-operative or post-operative complications. The principles of pre-operative assessment and surgery are discussed.

Infectious crystalline keratopathy.

We present a patient who developed a crystalline keratopathy after a penetrating keratoplasty. This rare complication can be caused by bacterial infection, and the patient responded to the appropriate antibiotic therapy. The literature is reviewed and possible causes and mechanisms of the crystalline appearance are discussed.

Changing patterns of early complications in cataract surgery with new techniques: a surgical audit.

We have undertaken a retrospective review of samples of case records from patients undergoing cataract surgery at St Thomas's Hospital over the years of the introduction of new extracapsular techniques and the widespread use of intraocular lens implants. We found no significant change in the proportion of patients achieving a corrected visual acuity of better than or equal to 6/12 three months after surgery. However, the pattern of complications was found to have changed in three respects. Firstly, there was a fall in the frequency of raised intraocular pressure requiring treatment associated with the abandonment of intracapsular surgery and the use of chymotrypsin. Secondly, a considerable number of patients who had had extracapsular extractions suffered from visually disabling posterior capsular thickening (13%). Thirdly, there was a downward trend in the rates of vitreous loss and of reduced vision at three months due to vitreous haemorrhage, vitritis, and retinal detachment in the patients undergoing extracapsular cataract surgery.

The lamellar corneal graft for optical indications.

The results of thirteen lamellar corneal grafts performed for optical indications are presented. Ten of the eyes maintained a clear graft; six patients achieved an acuity of 6/9 or better.

Acanthamoeba keratitis.

We report on four patients seen during the past two years who had acanthamoeba keratitis. One is described in detail. We believe that acanthamoebic eye infection is not rare. An immunofluorescent technique for localisation of amoebae and cysts is described. Our patients' response to propamidine and dibromopropamidine therapy was complicated by problems of toxicity.

Rational acyclovir therapy in herpetic eye disease.

Acyclovir has been widely used against the various manifestations of eye disease due to herpes simplex since it first became generally available in the UK nearly five years ago. This paper discusses the rational indications for its use, through considerations of its pharmacology and pharmacokinetics, and through results of the many clinical trials that have been carried out to investigate its effects since its clinical efficacy was first demonstrated in 1979.

Herpes simplex virus infections of the eye and their management with acyclovir.

Herpetic keratitis remains a prominent cause of recurrent or chronic and blinding corneal disease; areas of particular difficulty are indolent ulceration, herpetic keratouveitis, keratoplasty and problems associated with steroid therapy. Topical acyclovir has been widely demonstrated to be a safe and effective antiviral for ulcerative herpetic keratitis; furthermore its particular advantages of high efficacy, minimal toxicity and good ocular penetration, suggest that it should be the treatment of choice for patients within these other areas of particular difficulty.

Acyclovir in herpes simplex keratitis.

Herpes simplex keratitis is the most frequent cause of loss of vision from corneal disease in the industrialised world. This has led to the widespread use of a variety of antiviral drugs in treatment and these are reviewed, with particular attention to their clinical value. Study of the reports concerning the use of acyclovir (ACV) in this condition suggests that this antiviral may be more effective than others, not only in acute infections but possibly in herpetic iridocyclitis and also as a prophylactic antiviral cover following corneal grafting.

Herpetic iridocyclitis.

Twenty patients with presumptive herpetic iridocyclitis without active corneal inflammation received either topical idoxuridine 0.5% or acyclovir 3% ointment. The uveitis of all ten patients treated with acyclovir resolved within one to eight weeks. Four of ten patients treated with idoxuridine worsened but subsequently responded to topical prednisolone 0.3%. The pathogenesis of herpetic iridocyclitis is discussed with a literature review.

Prognostic indicators of herpetic keratitis. Analysis of a five-year observation period after corneal ulceration.

Clinical features of 152 patients with herpetic keratitis after a five-year observation period were analyzed. When compared with dendritic ulceration, geographic ulcers that had been symptomatically present for a longer time were more likely to have been treated with a topical steroid and took longer to heal. After treatment of the corneal ulceration, 40% of the patients experienced a recurrent herpetic ulcer, 25% experienced disciform or irregular stromal keratouveitis, 5% experienced ocular hypertension, and 6% had a decrease in visual acuity caused by corneal scarring. Recurrent ulcerative herpetic keratitis occurred more frequently in men and in patients who entered the study with a history or previous herpetic ulceration.

Bilateral herpetic keratitis.

Thirty patients with bilateral herpetic keratitis were evaluated, 40% of whom were atopic. Stromal keratitis occurred in 40% of the eyes and recurrent ulceration in 68%. Four patients (5 eyes) developed secondary microbial keratitis. Visual acuity decreased to 6/60 or less because of corneal opacification in 17% of the eyes.