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Pars plana vitrectomy with gas tamponade is an effective method of treating this form of retinal detachment. Some macular holes close after this surgery.

SUMMARYWe undertook a prospective slit lamp examination of 56 eyes which had undergone routine phacoemulsification, in order to determine the incidence of metallic intrao The use of phacoemulsification in cataract surgery is increasing in the United Kingdom. The post operative finding of intraocular metal particles has long been recognised, such particles having been considered inert. 1 , 2 We attempted to examine and quantify this phenomenon, in the light of recent interest in 'metallosis' and the bioreactivity of titanium alloy. 3 -8 PATIENTS AND METHODS Clinical StudyFifty-four consecutive phacoemulsification patients (56 eyes) were studied. The phacoemulsification equipment contained a Venturi pump with two piezo-electric crystals operating at 28 kHz. The diameter of the needle barrel and the width of the phacoemulsification tunnel were 1 mm and 3.2 mm respectively.All patients were examined within 2 weeks of surgery by slit lamp biomicroscopy. Using maximum illumination and magnification, the iris stroma was examined with an angled beam (45°) directed first from the right and then the left. The patient's eye was examined in the primary position and then in upgaze and in downgaze. Particles often glinted when illuminated from one direction only. The number and position of particles were recorded by a single observer (CM.D.). Study of Phacoemulsification NeedlesTwelve phacoemulsification needles were examined under the operating microscope and the pattern of wear recorded by colour photography. One new and four used needles were further examined using a J eol JSM-35CF scanning electron microscope operating at 12 kV. RESULTS Clinical StudyFifty-six eyes of 54 patients were studied; average patient age was 73.4 years and the male to female ratio was 17 to 37. All operations were performed at Aberdeen Royal Infirmary by one of four consul tants.Metallic particles were noted in 48 eyes (86%). The number per eye ranged from 1 to 103 with a mean of 5.1. Only the largest reflected sufficient light to appear on a slit lamp photograph (Fig. 1). Many appeared no larger than a white blood cell. Particles appeared to be randomly distributed over the iris stroma, often within crypts. No accompanying clinical problems were seen. Under the reduced Eye (1995) 9, [434][435][436]

The aim of this study was to determine whether capsulotomy size influences visual performance. Snellen visual acuity and forward light scatter (light scattered towards the patient's retina, but out of the focussed retinal image) measurements using simple computer graphics based on van den Berg's technique were used to measure visual performance. Twelve patients were studied: 4 had small central capsulotomies through undilated pupils and 8 had wide capsulotomies through dilated pupils. The two groups were matched for age and pre-laser Snellen acuity. Following treatment, both groups had equal improvements in Snellen acuity. There was only a significant (p < 0.001) improvement in forward light scatter readings in the group who received wide capsulotomies. Measurements of forward light scatter are more sensitive than Snellen acuity testing in demonstrating loss of visual performance in patients with media opacities. It is recommended that pupils are dilated prior to Nd:YAG capsulotomy if forward light scatter from capsule remnants and the consequent glare disability are to be minimised.

Five children with an orbital recurrence of retinoblastoma have been successfully treated by a combination of excision biopsy of the tumour mass, radical orbital radiotherapy, and systemic chemotherapy. Nine previous children, consecutive with the five presented here, died from disseminated retinoblastoma after failure of earlier treatment programmes for orbital recurrence. An aggressive therapeutic approach is justified by this improvement in survival.Orbital recurrence of retinoblastoma after enucleation has carried a poor prognosis, with the mortality rate ranging from 94 to 100% and a mean survival of 14 months.'2 Deaths occur from the effects of direct extension into the central nervous system and from metastatic disease. Recommended treatment now includes local surgical excision of the recurrent orbital tumour with radical orbital radiotherapy and systemic chemotherapy.' We report on five children successfully treated in this manner (for summary of details see Table I).Case reports of 50 Gy in 26 fractions over 40 days and with intravenous vincristine and cyclophosphamide chemotherapy. She has been off treatment for over seven years and remains disease free. CASE 2 In March 1985 a 7-year-old girl presented with a right panuveitis and secondary glaucoma. Medical treatment failed, and four months after presentation she underwent cyclocryotherapy, lensectomy for secondary cataract, and biopsies of some iris nodules and a white friable mass at the inferior ora serrata. These indicated a diagnosis of retinoblastoma, and the eye was enucleated.Eight months after enucleation the patient was referred to this centre with a right orbital mass. A recurrence of retinoblastoma was confirmed by excision biopsy. Staging investigations were negative for metastatic retinoblastoma, and she received orbital radiotherapy to a dose of 44 Gy in 22 fractions over 30 days together with systemic chemotherapy with vincristine, cyclophospamide, cisplatinum, etoposide (OPEC protocol), and intrathecal methotrexate. She has been off treatment for over three years and remains well and disease free.

This prospective study investigated whether low-dose ionising radiotherapy preserved vision and caused membrane regression in patients with age-related subfoveal neovascular membranes (SFNVMs) or vascularised pigment epithelial detachments (PEDs) and relatively good initial visual acuities. Twenty-five patients with initial Snellen acuities of 6/24 or better were treated with low-dose external beam radiotherapy. Of the patients with SFNVMs, visual acuities were maintained or improved in 58% at 6 months and 53% at 1 year. Neovascular membrane size was assessed by image analysis and showed some regression in 47% and 41% at 6 and 12 months respectively. These results suggest that patients with SFNVMs and good vision may benefit from radiotherapy, faring better than previous reports of the natural history of this condition. Conversely, patients with vascularised PEDs did not appear to benefit from radiotherapy. Only 17% maintained their vision at 1 year and 33% suffered retinal pigment epithelial tears. The results from patients with SFNVMs and good initial vision, excluding those with vascularised PEDs, are encouraging however, any benefit from this treatment needs to be proven by controlled trials with long follow-up.

Purpose To compare the diagnostic accuracy of noncontact slitlamp examination with indirect ophthalmoscopy and scleral depression, in the identification of retinal tears. Methods A prospective study was performed using 17 patients who were referred with retinal tears. All were initially examined at the slitlamp with a hand-held Volk (noncontact) lens. The same observer then carried out indirect ophthalmoscopy with scleral indentation.Results In 17 eyes a total of 18 acute retinal u-tears were found. A total of 16 tears were picked up at the initial examination at the slitlamp (89%), while two were missed (11%). Conclusions Indirect ophthalmoscopy with scleral depression is the 'gold standard' for the identification of peripheral retinal tears. This small study has shown that although the majority of these can be picked up by the use of a noncontact lens at the slitlamp, 11% were missed using this technique.

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