Richard Clemett

High iron status in very low birth weight infants is associated with an increased risk of retinopathy of prematurity

OBJECTIVE To explore the hypothesis that excessive iron loads may increase the formation of free radicals and the development of retinopathy of prematurity in preterm infants, we carried out a prospective observational study of the association between transfusion volume, iron status, and retinopathy.

New Zealand experience of I125 brachytherapy for choroidal melanoma.

Purpose:  To examine patient survival, visual function and complications in all patients with choroidal melanoma treated with I125 brachytherapy between 1995 and 2003 at the authors’ institution. To compare the results from their institution with those from international series.

Serum and neutrophils alter the rate of excretory/secretory antigen release by Toxocara canis infective larvae in vitro

Summary Infective larvae of Toxocara canis are well suited for studies of nematode antigen expression in vitro. Larvae were labelled with 3H‐glucosamine, an approach permitting dual analysis of antigen quantity and composition. Their excretory/secretory (E/S) glycoproteins were efficiently labelled and antigen identity confirmed by immunoprecipitation, SDS‐PAGE and fluorography. Compartmental analysis revealed that common components of Mr 100–120 kD were present in somatic, surface and soluble material. The application of biosynthetic labelling and compartmental analysis of parasite responses in vitro to antibody, complement and neutrophils was tested. Results indicated that test larvae in vitro respond by quantitative rather than qualitative changes in antigen production. Specifically, human serum was shown to raise, and neutrophils depress, the rate of antigen release. The implications of these findings for establishing an in‐vitro model for analysis of host/parasite reciprocal adaptive responses are discussed.

Central retinal vein occlusion associated with liquorice ingestion.

During clinical examinations clinicians rarely inquire whether patients are using non-proprietary preparations in addition to prescription medications. This report highlights the role nonpropriety preparations may play in the pathogenesis of an ocular condition. A 62-year-old woman presented with an ischaemic central retinal vein occlusion. As she was leaving the consulting room she commented how fond she was of liquorice and offered a bag to the nursing staff. When asked to define ‘fond’ she admitted to a daily consumption of four 200 g packets of liquorice a day. At presentation her blood pressure was 190/90 mmHg and this was the only significant risk factor identified. 1 Four days later her blood pressure was recorded as 204/100 mmHg. Although essential hypertension is likely, the liquorice consumption would have contributed to her elevated blood pressure. The association between liquorice and hypertension is well known. For example a recent study has shown a systolic blood pressure increase of 3.1–14.4 mmHg in a linear dose–response after volunteers ingested 50–200 g/day for 2–4 weeks. 2 The active ingredient of liquorice is glycyrrhetic acid, 50 g of liquorice has 75 mg of glycyrrhetic acid. Glycyrrhetic acid inhibits 11 α hydroxysteroid dehydrogenase, which converts active cortisol to its inactive form. The liquorice therefore leads to an increase in cortisol and through its mineralocorticoid effect increased blood pressure. In this patient, liquorice intake is implicated in relation to her elevated blood pressure and probably contributed to her developing a central retinal vein occlusion. We recommended she stop the liquorice intake and referred her to her general practitioner for treatment of hypertension. She was started on bendrofluazide and in combination with the discontinuation of liquorice her blood pressure was maintained under 160/90 mmHg. Four months after the central retinal vein occlusion our patient developed a vitreous haemorrhage that required a right vitrectomy and retinal photocoagulation with endolaser. One year later there is no evidence of neovascularization. Carden et al. has drawn attention to the association between garlic tablet ingestion and postoperative retrobulbar haemorrhage resulting from this medication. 3 These authors have highlighted another potential side-effect from a non-prescribed medicine taken by a patient. Non-prescribed medicines are very popular with our patients despite being of questionable efficacy. 4 In today’s environment clinicians need to be informed about the effects of common nonpropriety preparations on our patients. Being aware of all medications employed by a patient through specific and direct questions will sometimes surprise and assist the ophthalmologist. Reece C Hall MB ChB 1 and Richard S Clemett FRANZCO 2

Simultaneous choroidal melanoma and rhegmatogenous retinal detachment.

A case is reported of a 30‐year‐old man who presented with the unusual combination of a unilateral inferonasal choroidal melanoma and an unassociated rhegmatogenous retinal detachment attributable to a large horseshoe tear in the superotemporal quadrant. Over 20 cases of simultaneous occurrence of these two phenomena have now been reported but this patient appears to be the youngest. The reports of this uncommon association are reviewed.