ABSTRACT.Purpose: To compare postoperative best distance visual acuity (VA), contrast sensitivity and colour perception with the blue light-filtering AcrySof Ò Natural (SN60AT) and AcrySof Ò single-piece (SA60AT) intraocular lenses (IOLs). Methods: This was a prospective, randomized, comparative, interventional study comparing postoperative performance between the SN60 and SA60 IOLs. There were nine patients (nine eyes) in the SN60 group and 10 patients (10 eyes) in the SA60 group. All patients were operated using phacoemulsification. Postoperative VA (Snellen chart), contrast sensitivity (Pelli-Robson contrast sensitivity chart) and colour perception (Farnsworth-Munsell D-15 panel test) were measured at 1, 3 and 6 months postoperatively. Results: Postoperative best corrected VA after 6 months was 20/20 or better in 89% of SN60 eyes and 100% of SA60 eyes. Postoperative contrast sensitivity scores improved significantly in both groups under both photopic and mesopic conditions. There were no statistically significant differences in contrast sensitivity scores between the SN60 and SA60 groups at any of the postoperative evaluation time-points. Postoperative colour perception improved significantly in both the SN60 and SA60 groups, and there were no statistically significant differences in colour perception performance between the two groups. Conclusion: The blue light-filtering AcrySof Ò Natural (SN60) IOL has postoperative visual performance comparable with that of the AcrySof Ò single-piece (SA60) IOL.

Pathological changes are reported in the anterior visual pathways of a 41 year old man with complex partial seizures treated with vigabatrin who developed bilateral visual field constriction. There was peripheral retinal atrophy with loss of ganglion cells and loss of nerve fibres in the optic nerves, chiasm, and tracts. No evidence of intramyelinic oedema was seen. These findings suggest that the primary site of injury lies within the ganglion cells in the retina. The degree of atrophy seen would suggest that the visual field loss is irreversible. (J Neurol Neurosurg Psychiatry 2001;70:787-789)

An illustrative case of septic superior ophthalmic vein thrombosis secondary to a staphylococcus orbital cellulitis is presented and correlated with autopsy findings. A literature review and discussion of the risks and benefits of anti-coagulation in this setting is outlined.

Optic disc swelling is a rare complication of inflammatory bowel disease. Previously reported cases have been attributed to peripapillary inflammation, optic disc ischaemia or intracranial hypertension. Postulated causes of optic nerve ischaemia include a local vasculitis or general hypercoagulability. The underlying aetiology of intracranial hypertension is often elusive. Older studies suggest a relationship between corticosteroid treatment and/or iron deficiency anaemia, while modern imaging emphasises the need to exclude dural venous sinus thrombosis.