A new technique of local anaesthetic administration has been used for 50 patients undergoing cataract extraction. The simple technique involves direct transconjunctival infiltration of local anaesthetic directly to the sub-Tenon's space, in the inferior-nasal quadrant, using a blunt 19-gauge Southampton cannula. This method seeks to avoid the risks ofretrobulbar haemorrhage, perforation ofthe globe, damage to the optic nerve, and injection into the subarachnoid space, whilst providing prolonged and reliable anaesthesia. Akinesia is achieved by the inferior-nasal placement of solution and if not sufficient, a top-up can easily be given. Patients graded any discomfort or pain using a 10 cm visual analogue graphical pain score chart with numerical and descriptive rating scale. The delivery of 50:50 mixture of lignocaine 2% and bupivacaine 0 5% anaesthetic was evaluated by patients with a median response of 'slight discomfort'. The operative procedure was graded with a median of 'no pain or discomfort', both for extracapsular cataract extraction and phakoemulsification. This is a new, modified, sub-Tenon technique which is simple, reliable, and which offers excellent anaesthesia and akinesia and avoids a sharp instrument being passed into the orbit. (BrJ Ophthalmol 1992; 76: 670674) In 1884 Knapp reported successful cataract extraction by topical anaesthesia using frequent drops of 5% cocaine. He commented on the need for more extensive anaesthesia if the iris is to be anaesthetised. Describing a technique for enucleation, he reported the successful use of a retrobulbar injection,' rotating the globe nasally and introducing a needle through the muscle cone temporally. In 1884 Turnbull also described a local anaesthetic technique for enucleation, where topical 4% cocaine was applied to the cornea and conjunctiva, followed by the opening ofTenon's fascia and cocaine being dropped into the cut.2 Blunt pointed scissors which were curved on the flat were introduced from the nasal side and drops instilled. This was reported as successful in causing anaesthesia and vasoconstriction.Today various methods oflocal anaesthesia are in use for cataract extraction including retrobulbar,3 peribulbar,4 subconjunctival,5 and subTenon's6 application oflocal anaesthetic solution. Moorfields Eye Hospital, The desire to find an alternative to retrobulbar City Road, London EC1V anaesthesia has been caused by a variety of 2PD

The BESSt formula was statistically significantly more accurate than the other techniques tested. Thus, it could significantly improve intraocular lens power calculation accuracy after keratorefractive surgery, especially when pre-refractive surgery data are unavailable.

Phacoemulsification and IOL implantation in microphthalmos/nanophthalmos was challenging but appears safer than previously reported. A shorter AL and abnormal IOP were significant risk factors for complications.

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Dr. Day was supported by the National Institute for Health Research (NIHR) Biomedical Research Centre based at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology. Dr. Stevens has been a consultant to Optimedica Inc., now part of Abbott Medical Optics.