Comparing the 1CU accommodative, multifocal, and monofocal intraocular lenses: a randomized trial.

OBJECTIVE: To compare the binocular near vision performance in patients implanted with the 1CU accommodating intraocular lens (IOL) with a multifocal and monofocal IOL. DESIGN: Prospective, randomized, double-masked clinical trial. PARTICIPANTS: Ninety patients presenting for cataract surgery to the Department of Ophthalmology, Hillingdon Hospital were randomized to receive the 1CU accommodative IOL, a multifocal IOL, or a monofocal IOL (control group). METHODS: Patients underwent bilateral sequential phacoemulsification with implantation of 1 of the 3 IOL types and were assessed at 3 and 18 months after second-eye surgery. MAIN OUTCOME MEASURES: Logarithm of the minimum angle of resolution distance and near visual acuities (VAs) (unaided and distance corrected), contrast sensitivity, and accommodative amplitude (near point and defocusing) were measured at 3 and 18 months. Reading speed was assessed at 18 months, and glare symptoms and spectacle independence were compared using a standardized questionnaire. RESULTS: Mean unaided and distance-corrected binocular near VAs were similar in the 1CU and multifocal and were significantly higher than the control group's (P<0.02). There was no significant difference in reading speed between any of the groups, but critical print sizes were similar in the 1CU and multifocal groups and significantly better than the control group's (P = 0.02). The accommodative range was highest in the multifocal group and lowest in the control group, and there was no significant difference between the 1CU and control groups for defocus or near point at 18 months. Of the 1CU group and control group, 71.4% and 63.2%, respectively, experienced no glare at 18 months, compared with only 25% of the multifocal group (P = 0.01). Of the 1CU group and multifocal group, 19% and 27.3%, respectively, were completely spectacle independent at 18 months; none of the control group was (P = 0.05). CONCLUSIONS: The 1CU accommodating IOL provides improved near vision compared with a monofocal IOL. There is a discrepancy between the near function and accommodative amplitude measured in the 1CU. The multifocal provides excellent near acuity, but photopic phenomena remain a problem inherent in the lens design.

Advances in retinal ganglion cell imaging.

Glaucoma is one of the leading causes of blindness worldwide and will affect 79.6 million people worldwide by 2020. It is caused by the progressive loss of retinal ganglion cells (RGCs), predominantly via apoptosis, within the retinal nerve fibre layer and the corresponding loss of axons of the optic nerve head. One of its most devastating features is its late diagnosis and the resulting irreversible visual loss that is often predictable. Current diagnostic tools require significant RGC or functional visual field loss before the threshold for detection of glaucoma may be reached. To propel the efficacy of therapeutics in glaucoma, an earlier diagnostic tool is required. Recent advances in retinal imaging, including optical coherence tomography, confocal scanning laser ophthalmoscopy, and adaptive optics, have propelled both glaucoma research and clinical diagnostics and therapeutics. However, an ideal imaging technique to diagnose and monitor glaucoma would image RGCs non-invasively with high specificity and sensitivity in vivo. It may confirm the presence of healthy RGCs, such as in transgenic models or retrograde labelling, or detect subtle changes in the number of unhealthy or apoptotic RGCs, such as detection of apoptosing retinal cells (DARC). Although many of these advances have not yet been introduced to the clinical arena, their successes in animal studies are enthralling. This review will illustrate the challenges of imaging RGCs, the main retinal imaging modalities, the in vivo techniques to augment these as specific RGC-imaging tools and their potential for translation to the glaucoma clinic.

Brain potentials during sentence verification: late negativity and long-term memory strength.

Subjects decided whether self-referential statements were true or false. Event-related potentials (ERPs) associated with final words creating false statements displayed a late negativity (N340) relative to ERPs for true completions. The size of this difference between true and false statements was greater for highly familiar statements (e.g. "My name is Ira") than for less familiar ones (e.g. "I go to bed late") even after all the statements had been practised a number of times. The late negativity appears to be associated with a discrepancy between presented and remembered information, and its magnitude reflects the long-term familiarity or strength of the remembered information.

Magnetic resonance imaging. Diverse appearances of uveal malignant melanomas.

Fifteen patients with uveal malignant melanomas were studied by magnetic resonance imaging. The magnetic resonance imaging appearances varied from those that have been reported previously to be characteristic of these tumors. In our series, malignant melanomas were of high signal on the T1 sequence and of variable but usually also of high signal on the T2 and Short Tau Inversion Recovery (STIR) sequences, a signal combination rarely described before. We postulate that magnetic resonance imaging appearances may be dependent on variations in histologic factors and on the type and field strength of the scanner used. It is widely believed that the paramagnetic melanin in malignant melanomas gives these tumors characteristic magnetic resonance imaging appearances, but our finding of diverse magnetic resonance imaging appearances for proved malignant melanomas suggests that this may not always be the case. We advise caution in diagnosing malignant melanomas from magnetic resonance imaging appearances alone.

Screening for cytomegalovirus retinitis in HIV-positive and AIDS patients.

The ability of physicians to screen for AIDS-related cytomegalovirus retinitis (CMVR) was studied at a London AIDS centre. Patients had undergone direct ophthalmoscopy as part of their general examination by the physicians and were referred if fundal abnormalities were found, if a focus of extra-ocular CMVR was present or if the patient complained of visual symptoms. The provisional diagnoses of the physicians were compared with the final diagnoses of the ophthalmologists. Of 348 consecutive patients referred for an ophthalmic opinion, the physicians made the correct diagnosis in 69% of those referred with a provisional diagnosis of CMVR, in 66% of those with normal fundi and in 81% of those with toxoplasma chorioretinitis. Those cases of CMVR which were misdiagnosed by the physicians were usually mistaken for other retinal pathology which would warrant a specialist referral. Screening for CMVR in HIV-positive and AIDS patients may safely be undertaken by physicians familiar with the ocular manifestations of HIV-related disease.

Spontaneous development of retinal ischaemia and rubeosis in eyes with retinal racemose angioma.

Two Cases are described of spontaneous vascular closure occuring in eyes with arteriovenous malformations, causing visual loss due to retinal ischaemia and rubcosis iridis.

Quantification of melanin and iron content in uveal malignant melanomas and correlation with magnetic resonance image.

Eleven patients with uveal malignant melanomas (MM) were studied by magnetic resonance (MR) imaging before enucleation. The MR appearances varied, but often were different from those previously reported to be characteristic of these tumours. Using an image analyser to assess quantitatively the melanin and iron content of each tumour, a wide range of tumour melanin concentrations was found, but universally low tumour iron concentrations. These values were compared with MR appearances that were quantified and expressed as contrast to noise ratios. The correlation between T1 and T2 shortening and increasing melanin content did not reach statistical significance. There was no correlation between MR appearances and iron content. The theories postulated to explain the diverse MR appearances of uveal MMs are discussed and variations in tumour melanin content and differences in scanner strengths are suggested as the most likely explanations.

Clinical and infrared pupillometry in central retinal vein occlusion.

Measurements of pupillary reactivity and size were recorded using neutral density filters and infrared pupillometry (IRP) in a prospective masked study of acute central retinal vein occlusion (CRVO) to quantify the two methods of measurement and to compare their value in the prediction of rubeosis. Thirty two patients were examined within 45 days of disease onset. The mean relative afferent pupillary defect (RAPD) with filters was significantly greater in patients who developed rubeosis than in those who did not (0.9 vs 0.3 log units; p = 0.012). Using IRP, the pupillary diameters in the dark (maximum) and in the light (minimum) were significantly greater, the rate of pupillary constriction was significantly lower, and the latency of constriction was significantly greater in affected eyes than in unaffected eyes. The differences between affected and unaffected eyes in the IRP parameters of latency, rate, maximum, and minimum pupillary diameters were significantly greater in patients who developed rubeosis than in those who did not. Discriminant analysis of the IRP parameters correctly and statistically significantly identified rubeotic patients with 83% sensitivity and 95% specificity. An RAPD of > or = 0.6 log units was 83% sensitive and 70% specific in this regard. It is concluded that pupillary reactions are abnormal in many patients with acute CRVO, as measured by both pupillometric methods. The degree of these abnormalities has a relationship to the development of rubeosis, and might prove useful in planning the follow up of these patients or in deciding whether to apply panretinal photocoagulation. The neutral density filter test is readily available but subjective. IRP is more specific, objective, and suited to further development, but requires sophisticated equipment.

Treatment failure in a case of fungal keratitis caused by Pseudallescheria boydii.

A case is presented of Pseudallescheria boydii fungal keratitis in an agricultural welder. Treatment with azole antifungal drugs (miconazole and itraconazole) and with penetrating keratoplasty was unsuccessful in eradicating the infection, and eventually the eye was eviscerated.

The electro-oculogram in central retinal vein occlusion.

As part of a prospective masked study, the electro-oculogram (EOG) was recorded from 28 patients within 48 days of developing central retinal vein occlusion (CRVO). The EOG light peak/dark trough ratio (Lp/Dt) x 100 was significantly lower in the affected than in the unaffected eyes of patients (p < 0.001), and abnormally low in absolute terms in 20 patients (71%). All unaffected fellow eyes had a normal EOG ratio. The mean Lp amplitude of affected eyes was significantly smaller than that of unaffected eyes (p < 0.001), whereas the differences in mean Dt amplitudes between affected and unaffected eyes were not statistically significant. The Lp amplitude in the affected eye was 48% or less of that in the unaffected eye in the eight patients (29%) who developed rubeosis iridis during the 9 month follow-up, and in six others. No patient whose Lp amplitude in the affected eye was greater than 48% of that in the unaffected eye, developed rubeosis. It is concluded that the Lp amplitude is abnormal in patients with acute CRVO. The degree of this abnormality bears a relation to the development of rubeosis, which might prove a useful indicator of whether to institute or withhold panretinal photocoagulation.

Appearances of choroidal osteomas with diagnostic imaging.

The diagnostic imaging appearances of three choroidal osteomas (osseous choristomas) are presented. This rare, benign choroidal tumour is being recognized with increasing frequency, and is important to remember in the differential diagnosis of any unusual mass in the ocular fundus lest it be mistaken for a more sinister lesion. All three osteomas were demonstrated by ocular ultrasound (US), fluorescein angiography (FA) and computed tomography (CT) but none by plain radiography. None of the lesions was visible on magnetic resonance imaging (MRI); the reason for this is probably the bony nature of the tumours. The appearances of choroidal osteomas on US, FA, plain radiography and CT are discussed. To our knowledge this is the first report of a series of choroidal osteomas investigated by MR.

Spontaneous hyphaema arising from a strand of persistent pupillary membrane.

A case is reported of spontaneous hyphaema arising from a persistent strand of vascularised pupillary membrane. This strand, and an aneurysmal dilatation from which haemorrhage occurred, were illustrated by fluorescein angiography. The embryogenesis of pupillary membranes is discussed and the literature is reviewed with reference to spontaneous hyphaema.

Retinal ischaemia and relative afferent pupil defects in central retinal vein occlusion.

A consecutive series of 40 patients were assessed for relative afferent pupil defects and retinal ischaemia by fluorescein angiography. A strong correlation was found between density of afferent defect and area of retinal non-perfusion. There was an increasing incidence of rubeosis iridis with more severe grades of afferent defects or ischaemia.

The efficacy of 0.75% bupivacaine with pH adjustment and hyaluronidase for peribulbar blockade: the incidence of prolonged ptosis.

A prospective, double masked, randomised study was performed to compare the speed of onset of peribulbar anaesthesia using pH adjusted 0.75% bupivacaine, with and without the addition of hyaluronidase. No significant difference in speed of onset occurred due to the addition of hyaluronidase. There were 7 cases of post operative ptosis in the study group, including 1 case of orbital apex syndrome and 2 cases of transient 3rd nerve palsy. This incidence of post operative ptosis using pH adjusted 0.75% bupivacaine was statistically significantly greater than in a matched control group who received a 50:50 mixture of 1% lignocaine and 0.5% bupivacaine with hyaluronidase (p < 0.05). The possible causes of this increased incidence of post operative ptosis are discussed.

Localised Wegener's granulomatosis presenting as an orbital pseudotumour with extension into the posterior cranial fossa.

Pseudotumour has rarely been reported to invade the intracranial cavity. We present a case of pseudotumour which extended intra-cranially into the posterior cranial fossa. The patient had circulating antineutrophil cytoplasmic antibodies in titres diagnostic for Wegener's granulomatosis. In the absence of clinical renal or respiratory tract disease, the case may represent a newly recognized sub-type of "localised" Wegener's granulomatosis.

Evaluation of efficacy and safety of ciprofloxacin ophthalmic solution versus chloramphenicol.

The results of this clinical study demonstrate that ciprofloxacin ophthalmic solution 0.3% is as safe and as effective as 0.5% chloramphenicol ophthalmic solution in the treatment of conjunctivitis and blepharitis of bacterial aetiology. Both agents achieved microbiological improvement rates in excess of 90% after 1 week's treatment. On ciprofloxacin 93.5% of patients were judged clinically cured or improved versus 84.6% on chloramphenicol after 1 week. There were no serious adverse affects. One patient in each group suffered drug-related side-effects (chemosis, erythema) which resolved on discontinuation or changing of therapy. Cirpofloxacin is not associated with the rare, but serious, side effect of aplastic anaemia which is associated with chloramphenicol use. On the evidence of this study ciprofloxacin would appear to be an appropriate agent for general use as a topical ophthalmic formulation.

Topical ciprofloxacin in the treatment of blepharitis and blepharoconjunctivitis.

An international multicentre study assessed the clinical and antibacterial efficacy of a new topical ophthalmic formulation of the quinolone antimicrobial agent ciprofloxacin and compared it with that of tobramycin ophthalmic solution in patients with blepharitis and blepharoconjunctivitis. The study consisted of a randomised double-masked between-group evaluation of 464 patients, 230 of whom were treated with ciprofloxacin and 234 with tobramycin. There was qualitative and quantitative bacteriology, and clinical assessment of ocular symptoms and signs before and after a seven-day course of treatment. Bacteriological cultures demonstrated eradication or reduction of potentially pathogenic bacteria in 93.7% of eyes (ciprofloxacin) versus 88.9% of eyes (tobramycin), seven days after starting treatment. Clinically more than 80% of patients in both treatment groups were cured or improved after seven days. No statistically significant differences were observed between the two treatment groups. No serious side-effects were observed after use of either antimicrobial agent. Ciprofloxacin ophthalmic solution appears safe and effective. The spectrum of activity and clinical efficacy of this new formulation are discussed in comparison with currently used antimicrobial agents.

Suturing of digital lacerations: digital block or local infiltration?

A prospective trial was carried out to assess the relative efficiency of digital block and local infiltration as methods of anaesthesia when suturing lacerations of the digits. A standard technique and questionnaire were applied to a consecutive group of 62 patients attending the Accident Department of the Bristol Royal Infirmary. Digital block was found to be a more effective technique than local infiltration for anaesthetising digital lacerations.

The sight test fee: effect on ophthalmology referrals and rate of glaucoma detection.

OBJECTIVE: To assess changes, if any, in the numbers of referrals and outcome of glaucoma referrals to the hospital eye service since the introduction of the sight test fee on 1 April 1989. DESIGN: Review of referral records and clinical notes. SETTING: Referrals to the Bristol Eye Hospital. SUBJECTS: 51,919 patients referred to the Bristol Eye Hospital between 1984 and 1992. 9438 case notes of patients referred between 1987 and 1991 were examined in detail. MAIN OUTCOME MEASURES: Numbers of referrals; rate of adult true positive glaucoma referrals. RESULTS: Referrals to the Bristol Eye Hospital were between 13.7% and 19.0% fewer than expected after the introduction of the sight test fee. True positive glaucoma referrals were reduced by the same proportion. CONCLUSIONS: The numbers of patients being identified as requiring treatment or follow up for potentially blinding glaucoma have declined by nearly one fifth since the introduction of the sight test fee. An increased prevalence of preventable blindness may result.

Development of a virtual reality training curriculum for phacoemulsification surgery.

PURPOSE: Training within a proficiency-based virtual reality (VR) curriculum may reduce errors during real surgical procedures. This study used a scientific methodology to develop a VR training curriculum for phacoemulsification surgery (PS). PATIENTS AND METHODS: Ten novice-(n) (performed <10 cataract operations), 10 intermediate-(i) (50-200), and 10 experienced-(e) (>500) surgeons were recruited. Construct validity was defined as the ability to differentiate between the three levels of experience, based on the simulator-derived metrics for two abstract modules (four tasks) and three procedural modules (five tasks) on a high-fidelity VR simulator. Proficiency measures were based on the performance of experienced surgeons. RESULTS: Abstract modules demonstrated a 'ceiling effect' with construct validity established between groups (n) and (i) but not between groups (i) and (e)-Forceps 1 (46, 87, and 95; P<0.001). Increasing difficulty of task showed significantly reduced performance in (n) but minimal difference for (i) and (e)-Anti-tremor 4 (0, 51, and 59; P<0.001), Forceps 4 (11, 73, and 94; P<0.001). Procedural modules were found to be construct valid between groups (n) and (i) and between groups (i) and (e)-Lens-cracking (0, 22, and 51; P<0.05) and Phaco-quadrants (16, 53, and 87; P<0.05). This was also the case with Capsulorhexis (0, 19, and 63; P<0.05) with the performance decreasing in the (n) and (i) group but improving in the (e) group (0, 55, and 73; P<0.05) and (0, 48, and 76; P<0.05) as task difficulty increased. CONCLUSION: Experienced/intermediate benchmark skill levels are defined allowing the development of a proficiency-based VR training curriculum for PS for novices using a structured scientific methodology.