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The visual function of 35 patients with a diagnosis of idiopathic intracranial hypertension was assessed prospectively over a 3 year period. In assessing the visual function of cases of idiopathic intracranial hypertension a number of tests were employed including visual field assessment with Humphrey and Goldmann perimeters and documentation of visual acuity and contrast sensitivity. Loss of visual function is the only serious complication and may occur early or late in the course of the condition. An appropriate and sensitive clinical assessment regime is therefore of importance in the outpatient situation. Visual field assessment was documented as the most sensitive to detection of visual loss, with statistically greater sensitivity in comparison with visual acuity and contrast sensitivity testing. Detection of asymptomatic visual loss indicates the necessity for visual monitoring to ensure detection of insidious visual loss. The types of visual field defects noted in this study were typical of anterior optic nerve pathology of raised intracranial pressure and commonly included arcuate defects, nasal steps and global constriction. Visual loss was noted at presentation and during follow-up in up to 87% of patients using Goldmann perimetry and up to 82% of patients using Humphrey perimetry. The visual status improved significantly throughout the follow-up period and the final visual outcome was excellent or good in 83% of patients.

Aim-Two prospective studies were carried out in order to investigate (1) the rise in intraocular pressure (IOP) following peribulbar anaesthesia with a fixed volume of anaesthetic agent administered by a single surgeon, and (2) the efficacy of ocular compression with the Honan balloon for lowering IOP. Glaucomatous eyes were excluded from both studies. Methods-In study group ' Ophthalmol 1996; 80: 394-397) Peribulbar anaesthesia is a widely used local anaesthetic technique for eye surgery in the UK. The usual volume of anaesthetic agent used varies between 6 and 10 ml and since the average orbital volume is only 30 ml there is an associated rise in intraorbital and intraocular pressure (IOP). The magnitude of this immediate post-injection rise is variablel-3 and the volume of anaesthetic used may have an effect.2 4Because of the desirability of low IOP (and low vitreous pressure) during intraocular surgery, some form of ocular compression is often applied for a variable period of time either before but usually after administration of peribulbar anaesthesia. Ocular compression has been shown to be effective in lowering IOP in normal eyes in the absence of intraorbital injection5 as well as in eyes which have received peribulbar injections.6 A recently published study questions the necessity of ocular compression.7The aim of this study was, firstly, to identify the extent and the variability in IOP rise immediately after peribulbar injection and, secondly, to investigate the importance of ocular compression in facilitating the subsequent IOP fall. Previous studies have been hampered by including differing techniques and volumes of injectate withia the same study, measuring IOP values at inappropriate intervals and in some cases not having excluded patients with glaucoma or separated them out before data analysis. We have addressed these issues in the present study by having a single surgeon use the same technique and volume of injectate in all cases studied.Patients and methods Study group 1 consisted of 36 consecutive patients undergoing peribulbar anaesthesia for cataract and/or implant surgery. IOP measurements were made immediately before (A) and immediately after administration of the anaesthetic (B) with the Perkins handheld applanation tonometer. Each patient received 5 ml of anaesthetic from an inferotemporal injection through the conjunctiva and a further 5 ml from a medial injection through the caruncle. The anaesthetic solution consisted of 5 ml of lignocaine 2% with 1 in 200 000 adrenaline and 5 ml of 0-5% bupivacaine. A Honan's ocular compression balloon was then applied to the eye and inflated to a pressure of 30 mm Hg for a variable duration range (D) immediately after which the IOP was again measured (C).Study group 2 consisted of 20 consecutive patients undergoing peribulbar anaesthesia for cataract surgery. The anaesthetic technique and anaesthetic agents used were identical to those for study 1. IOP values were measured immediately before (A) and immediately after administration of...

Selective laser trabeculoplasty appears to cause transient corneal endothelial changes in most patients that have no impact on cell count or visual acuity. Further work is required to elucidate the mechanism of this phenomenon and any long-term impact.