Summary Purtscher’s retinopathy presents to the clinician as loss of vision in a patient with a history of a possible precipitating event such as recent major trauma, pancreatitis, childbirth or renal failure. The ophthalmological picture is one of ischaemia at the posterior pole with white patches of oedema and haemorrhages concentrated around the optic disc. The most probable pathological cause is embolisation of the peripapillary terminal arterioles supplying the superficial peripapillary capillary net. The nature of the embolic particles remains uncertain. Complement-mediated aggregates, fat, air, fibrin clots and platelet clumps may all be involved in what is most likely to be a multifactorial process. There is at present no recognised treatment for the condition.

The treatment ofacute angle closure glaucoma has been influenced by the development of the YAG laser and its ability to perform iridotomies as an outpatient procedure. In this retrospective study the results of YAG iridotomy were compared with surgical peripheral iridectomy. When compared with surgical peripheral iridectomy patients, YAG iridotomy patients were at greater risk of proceeding to further surgery, with this risk being significantly associated with increasing duration of attack. The authors suggest that in selected cases, surgical iridectomy should be given consideration as a primary procedure.

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Laser panretinal photocoagulation (PRP) reduces visual loss in proliferative diabetic retinopathy but decreases peripheral retinal function. The Driver and Vehicle Licensing Centre (DVLC) states that when a patient volunteers that he or she has had photocoagulation, a questionnaire will then be sent to the patient's diabetic physician who can refer the patient for formal field testing. Of 30 patients who had PRP, 15 failed DVLC visual field regulations using the Esterman binocular field test on the Humphrey field analyser. The failures were more likely to have had treatment with a xenon laser, but there was no difference between the groups as regards age, number of burns or whether an argon or diode laser was used. The patients who failed were more likely to be hypertensive (p = 0.04). Two patients with unilateral PRP could not meet the driving regulations because of other field defects. Diabetes itself causes field defects, and therefore even with small amounts of laser, formal field testing may be necessary.

Argon and diode laser pan retinal photocoagulation are used in diabetic proliferative retinopathy. This is a prospective study of the effects of each laser type on peripheral field loss. It shows that diabetics have significantly reduced peripheral field prior to laser compared to normals (p = 0.006). With identical pan retinal photocoagulation with either argon or diode laser there is no difference in field loss.