Unilateral varicella zoster virus ophthalmicus and contralateral acute retinal necrosis.

We report two patients who developed varicella zoster virus (VZV) ophthalmicus complicated by ipsilateral keratouveitis, and within 4 weeks developed acute retinal necrosis (ARN) in the contralateral eye. The ipsilateral retina was spared in each case. One patient had systemic lupus erythematosus (SLE) and the other Hodgkin's disease. Both patients were in remission at the time of presentation.

Macular hole surgery with silicone oil.

PURPOSE: Macular hole surgery usually involves gas tamponade which necessitates a variable period of postoperative posturing in a face-down position. A number of patients find this difficult or impossible for medical or social reasons. This study reviews our experience of macular hole surgery using silicone oil tamponade with no restriction of posturing. METHODS: Sixteen consecutive cases of macular hole (stage III/IV) surgery where silicone oil was used for tamponade were reviewed. Group A patients were unable for medical or social reasons to maintain a face-down posture and Group B patients had previous failed surgery with gas tamponade. RESULTS: Anatomical closure of hole was achieved in 81% (13/16) of all cases and 88% (7/8) of cases with no previous surgery (Group A) with a mean follow-up of 7.5 months (range 4-24 months). Mean visual improvement (log(MAR) value of visual acuity) for Group A and Group B were 0.41 and 0.03, respectively. CONCLUSIONS: The success rate of macular hole surgery using silicone oil as tamponade, in cases with no previous surgery, is comparable to that achieved when gas is used as tamponade. Although good anatomical success can be achieved in cases with previous failed surgery, the visual outcome is less rewarding. Silicone oil is an alternative to gas tamponade for macular hole surgery in patients who are unable or unwilling to posture. However, it has to be borne in mind that silicone oil tamponade is not without risks.

Iris crystals in chronic uveitis.

AIMS: To analyse the unusual physical sign of iris crystals occurring in patients with uveitis. METHODS: Demographic details and clinical features were documented in 24 patients with chronic uveitis and iris crystals. Plasma immunoglobulin subclasses were measured, and a histopathological review of iridectomy specimens from 33 patients with chronic uveitis was also undertaken. RESULTS: The mean age of patients was 38 years, with a slight preponderance of females. 17 patients had Fuchs' heterochromic cyclitis although a number of other uveitis entities were represented. There was no correlation between severity of clinical signs and presence of iris crystals. Over a mean follow up period of 15 months no significant change in the number, size, or position of the crystals was seen except in four patients who underwent intraocular surgery. Only three patients had raised plasma IgG1. The review of the histology of iridectomy specimens failed to show evidence of Russell body formation in any patient. CONCLUSIONS: Iris crystals appear to be rare but may be underreported as they are small and can easily be missed. They are likely to be associated with disease processes in which there is active immunoglobulin production within the anterior chamber, such as Fuchs' heterochromic cyclitis.

Simultaneous posterior chamber intraocular lens implant combined with vitreoretinal surgery for intraocular foreign body injuries.

UNLABELLED: To evaluate the safety of simultaneous posterior chamber intraocular lens (IOL) implant combined with complex vitreoretinal surgery for ocular trauma due to intraocular foreign body (IOFB). METHODS: We undertook a retrospective analysis of 10 patients who had undergone simultaneous cataract extraction, vitreoretinal surgery, removal of IOFB and posterior chamber IOL implant, for ocular trauma due to IOFB. The visual outcome and complications were noted. The surgical procedure is described. RESULTS: Ten young, male patients were followed for 5-30 months post-operatively. The post-operative visual acuity in the operated eye remained the same or improved as compared with their pre-operative vision. Eight patients had a visual acuity of 6/9 or better. One patient developed post-operative infective endophthalmitis. Three patients had retinal detachment post-operatively. The IOL was stable in all patients. CONCLUSIONS: Simultaneous posterior chamber IOL implant with vitreoretinal surgery is safe in selected cases of severe ocular trauma due to IOFB. It allows early visual rehabilitation of young, working patients.

Is hyaluronidase helpful for peribulbar anaesthesia?

A prospective, randomised controlled study was performed to investigate whether hyaluronidase improved the efficacy of peribulbar anaesthesia. Ninety-two patients undergoing peribulbar anaesthesia for intraocular surgery all received 10 ml of an anaesthetic solution consisting of a 50:50 mixture of 2% lignocaine with 1 in 200,000 adrenaline and 0.5% bupivacaine. Patients were randomised to a hyaluronidase group which received 150 IU/ml hyaluronidase in this anaesthetic solution (a higher concentration than previous studies) or a control group which received no hyaluronidase. There were 44 patients in the hyaluronidase group and 48 patients in the control group. All anaesthetic injections were administered by an experienced ophthalmologist and no supplementary injections were required in any case. The mean time interval between administration of the block and commencement of surgery was 22 minutes. No statistically significant difference was found between the two groups for pre-operative akinesia (p = 0.16), intraoperative akinesia (p = 0.25), eyelid paralysis (p = 0.72), objective analgesia (p = 0.23) or subjective analgesia (p = 0.60). The majority of patients in both groups achieved excellent akinesia, eyelid paralysis and analgesia. The reasons for these findings in the light of previously conflicting reports on the value of hyaluronidase in peribulbar anaesthesia are discussed.

The effect of temperature on the discomfort caused by topical local anaesthesia.

The warming of local anaesthetic solutions to reduce the pain felt on injection is common practice in a number of medical sub-specialties. A study was undertaken to assess the effect of temperature on the discomfort caused by local anaesthetic eye drops. Tropical anaesthetics amethocaine 1%, oxybuprocaine 0.4% and lignocaine 4% were studied, and after the application of strict exclusion criteria 60 patients were selected, 20 patients for each anaesthetic. Each patient group received a topical anaesthetic at 42 degrees C in one eye and at room temperature in the other. A 10 point visual analogue scale was used to assess the discomfort experienced. No statistically significant difference was found between the discomfort caused by drops at each temperature for any of the three anaesthetics studied. There appears no benefit in warming topical anaesthetic agents prior to their use.

A novel conjunctival incision for horizontal strabismus surgery.

We present a randomised, controlled study of a new approach to conjunctival incision in horizontal strabismus surgery. A peritomy is performed from 2 to 10 o'clock inferiorly allowing free access to the horizontal recti from below. No limbal stay sutures are required and the conjunctiva is left unsutured on completion of surgery. Results of 13 patients are presented. Each patient is paired with a control on whom conventional surgery was performed. The pairs were matched for age and surgeon. Results show a decrease in the time taken for the procedure and decreased discomfort in the post-operative period. The external appearance of the operated eye and the incidence of complications over a 6 week period were the same for both techniques.