Intravitreal bevacizumab for the treatment of retinopathy of prematurity: a case report.

OBJECTIVE: We report the first case in Scotland of a premature infant treated for retinopathy of prematurity with bevacizumab. METHOD: A case report and a review of the literature are presented. RESULTS: Retinopathy of prematurity is a leading worldwide cause of childhood blindness. Conventional laser treatment results in destruction of the peripheral retina and does not prevent all cases of vision loss, particularly in Zone I disease. We present the case of a baby born at 26(+3) weeks who developed stage 3+ disease located in Zone I of the retina. The patient was treated with bilateral bevacizumab injections and achieved complete resolution of his retinopathy. CONCLUSION: Bevacizumab therapy for the treatment of retinopathy of prematurity is an effective and inexpensive treatment that can readily and quickly be administered by a competent ophthalmologist without the need for specialist equipment.

Costs and consequences of automated algorithms versus manual grading for the detection of referable diabetic retinopathy.

AIMS: To assess the cost-effectiveness of an improved automated grading algorithm for diabetic retinopathy against a previously described algorithm, and in comparison with manual grading. METHODS: Efficacy of the alternative algorithms was assessed using a reference graded set of images from three screening centres in Scotland (1253 cases with observable/referable retinopathy and 6333 individuals with mild or no retinopathy). Screening outcomes and grading and diagnosis costs were modelled for a cohort of 180 000 people, with prevalence of referable retinopathy at 4%. Algorithm (b), which combines image quality assessment with detection algorithms for microaneurysms (MA), blot haemorrhages and exudates, was compared with a simpler algorithm (a) (using image quality assessment and MA/dot haemorrhage (DH) detection), and the current practice of manual grading. RESULTS: Compared with algorithm (a), algorithm (b) would identify an additional 113 cases of referable retinopathy for an incremental cost of pound 68 per additional case. Compared with manual grading, automated grading would be expected to identify between 54 and 123 fewer referable cases, for a grading cost saving between pound 3834 and pound 1727 per case missed. Extrapolation modelling over a 20-year time horizon suggests manual grading would cost between pound 25,676 and pound 267,115 per additional quality adjusted life year gained. CONCLUSIONS: Algorithm (b) is more cost-effective than the algorithm based on quality assessment and MA/DH detection. With respect to the value of introducing automated detection systems into screening programmes, automated grading operates within the recommended national standards in Scotland and is likely to be considered a cost-effective alternative to manual disease/no disease grading.

Incidence and visual outcome of acute endophthalmitis after cataract surgery--the experience of an eye department in Scotland.

AIM: Endophthalmitis remains one of the most dreaded complications of modern cataract surgery. Its incidence in the UK has been estimated but accurate published data on the incidence at a regional level are scarce. This audit examines the incidence and visual outcome of endophthalmitis from a single eye department in Scotland (UK) over a 7-year period. Findings are compared with those from other series. METHODS: A retrospective consecutive audit of all cases of acute endophthalmitis treated between 1 January 2000 and 31 December 2006 at the Southern General Hospital in Glasgow (Scotland, UK) was undertaken. Details of each case (presentation, treatment and outcome of endophthalmitis) were recorded. Cross-tabulations were performed to identify prognostic factors of visual outcome. RESULTS: Twenty-five patients were treated for endophthalmitis over the audit period. The incidence of endophthalmitis was 0.20% (95% CI 0.10 to 0.30%). There were 12 (48%) culture-positive cases with coagulase-negative staphylococcus accounting for 58%. After treatment, 16 patients (64%) achieved driving-standard vision or better. Poor vision at presentation and streptococcal endophthalmitis were associated with poor visual outcome. CONCLUSION: The incidence of endophthalmitis in this series is comparable to larger studies, suggesting that accepted benchmarks, despite being estimates, reflect UK practice. Visual outcome, with treatment, can be favourable in a significant proportion of patients.

Retinopathy of prematurity: an optimum screening strategy.

OBJECTIVE: We sought to find out whether birth weight of less than 1251 g or gestational age less than 30 weeks could provide a safe and efficient screening criteria of detecting treatable retinopathy of prematurity (ROP). METHODS: Infants either with a birth weight less than 1500 g or gestational age less than 32 weeks were screened for ROP during an 8-year period. RESULTS: In our study, the incidence of ROP was 36 of 187 (19.3%) infants. Although there was a slight increase in the number of infants screened over the years, the incidence of ROP of any stage remained stable. The maximum stage of ROP reached was stage 1 in 10 of 187 (5.3%), stage 2 in 8 of 187 (4.3%), and stage 3 in 18 of 187 (9.6%) infants. Among those with stage 3 disease, threshold ROP was present in 16 of 18 (88.9%). All infants with threshold ROP had a BW less than 1100 g and gestational age less than or equal to 28 weeks. Significantly fewer babies (105/187, or 56%) would have been examined had inclusion criteria of a birth weight of less than 1251 g and gestational age less than 30 weeks been applied. In addition, 31% (134/437) of screening examinations could have been avoided. CONCLUSIONS: Our study suggests that a birth weight of less than 1251 g and gestational age less than 30 weeks can be safely and efficiently used to screen infants without missing a diagnosis of sight-threatening ROP in our catchment population.

Economic costs of cataract surgery using a rigid and a foldable intraocular lens.

Optimal delivery of healthcare requires consideration of various costs. A foldable intraocular lens (IOL) is more expensive than an equivalent rigid IOL. However, surgical and post-operative costs may make a foldable IOL economically preferable. We compared the economic costs of cataract surgery plus implantation of a foldable IOL with implantation of a rigid IOL. Prospective audit of the clinical records of 82 pseudophakes; 39 implanted with a rigid IOL and 43 implanted with a foldable IOL by one surgeon. Average follow-up periods were 25 +/- 7 months and 23 +/- 5 months respectively. There was no difference between the two groups for the follow-up period (P = 0.55), number of post-operative complications (P = 0.25) or cost of post-operative visits (P = 0.83). The cost of single-use theatre equipment was greater for the rigid-IOL group (P= 0.0001). The total identified cost per patient was greater for the foldable-IOL group (P = 0.0001). Despite possible technical advantages, implantation of the foldable IOL did not provide an economic benefit, either in the initial cost or in the costs of post-operative care. Over the 2-year period, implanting with the rigid IOL cost, on average, Pound Sterling57 less per patient. Despite this economic difference, a cost-benefit analysis is required, since other factors may be more important.

A comparison of visual performance between a rigid PMMA and a foldable acrylic intraocular lens.

PURPOSE: To examine post-operative visual outcomes when using micro-incision surgery and a three-piece, foldable acrylic intraocular lens (IOL) and when using small-incision surgery and a one-piece, rigid polymethyl-methacrylate (PMMA) IOL. METHODS: Phacoemulsification and IOL implantation was conducted by one surgeon on 86 subjects (aged 50-89 years) with cataracts. Of these subjects, 67 completed the study. Subjects were implanted either with a foldable IOL (n = 38) or a rigid IOL (n = 29). Best corrected Snellen visual acuity and contrast sensitivity (2-28 cycles/degree) were measured approximately 2 months post-operatively. Comparisons were made between the pseudophakic groups and an additional group of 28 age-matched, normal subjects (aged 58-81 years). Non-parametric (Kruskal-Wallis and Mann-Whitney U) as well as parametric (ANOVA and Pearson) statistics tests were used in the analysis of results. RESULTS: All pseudophakes had corrected visual acuity of 6/9 or better. There were no significant differences in visual acuity (Kruskal-Wallis, p = 0.61) or contrast sensitivity (ANOVA, p = 0.33) between the three groups. The mean residual refractive error of the foldable IOL group was hypermetropic in comparison with the rigid IOL group but not significant at the 99% level of probability (Mann-Whitney U, p = 0.02). There was no significant difference in astigmatism between the groups. CONCLUSIONS: Implanting a foldable acrylic IOL gave no post-operative benefit in visual acuity and contrast sensitivity to pseudophakes over a less expensive rigid PMMA IOL, within this post-operative period. This study did not provide a comparison between the two lenses regarding post-operative complications, in particular the important long-term complication of posterior capsular opacification (PCO). Until and if any particular advantage of a given IOL in reduced incidence of PCO is confirmed, it appears more economical to implant the conventional rigid PMMA IOL using small-incision surgery.

Systemic diclofenac sodium to maintain mydriasis during phacoemulsification.

PURPOSE: To determine whether systemic diclofenac sodium affects the maintenance of mydriasis during phacoemulsification and to compare pupil diameter regression rates with those in a control group. SETTING: An ophthalmic unit of a National Health Service Trust Hospital in the United Kingdom. METHOD: A prospective, randomized control study of 100 patients presenting for cataract surgery was undertaken. Both groups were administered an identical mydriatic regime commencing 1 hour before surgery. In addition, the diclofenac group (n = 48) received 50 mg of oral diclofenac sodium 1 hour before surgery. Both the control (n = 52) and diclofenac groups had phacoemulsification by one experienced surgeon using a standard technique. The surgeon was masked as to which group the patient belonged. The irrigating fluid in all cases contained adrenaline. Pupil diameter was measured at five stages during surgery and recorded along with the times relative to the start of the procedure. RESULTS: Mean pupil diameter in the diclofenac group was slightly larger than in the control group, but the difference was not significant. Although mean pupil diameter at the start of surgery was 0.4 mm greater in the diclofenac group, the slopes of regression in pupil diameters were virtually identical between the first three stages of surgery, after which a slight reversal occurred in both groups. The slope of regression of mydriasis was small in both groups. CONCLUSION: Systemic diclofenac sodium 50 mg given orally 1 hour before surgery did not significantly inhibit miosis when compared with a control group. Regression rates of pupil mydriasis were small in both groups.

A comparison of colour Doppler imaging of orbital vessels and other methods of blood flow assessment.

BACKGROUND: Comparison of the haemodynamic measurements obtained by colour Doppler imaging and other methods of ocular blood flow measurements was desired. METHODS: The blood velocity findings from colour Doppler imaging of patients with central retinal vein occlusion were compared to the results of fluorescein video-angiography, continuous tonography and ophthalmodynamometry. RESULTS: Patients with low or undetectable blood velocities in the central retinal vein had longer retinal dye transit times on fluorescein video-angiography. Tonography showed a positive correlation with the velocities in the ophthalmic artery, but ophthalmodynamometry showed a negative correlation with these velocities. CONCLUSION: The relationships between the blood velocities in orbital vessels and other blood flow measurements emphasise that there is a complex interaction of the blood flow parameters. Care must therefore be taken when interpreting the results of studies.

Detection of diabetic retinopathy by scanning laser ophthalmoscopy.

A scanning laser ophthalmoscope (SLO) was used to examine the fundi of 54 diabetic patients through undilated pupils and the results compared by an experienced ophthalmologist with clinical examination through dilated pupils to assess the effectiveness of the SLO in detecting diabetic retinopathy. Whilst the SLO was not as good at detecting cotton wool spots and subtle intraretinal microvascular abnormalities, it did not miss any active new vessel formation and all eyes needing treatment would have been referred.

Subclinical operating microscope retinopathy: the use of static perimetry in its detection.

Focal retinal pathology and dysfunction as a sequel to manifest damage due to operating microscope illumination is well recognised. We wished to determine whether retinal dysfunction could be identified in the absence of clinically visible lesions. We therefore have conducted a prospective controlled study on 36 patients undergoing cataract surgery and 27 control subjects. A Wild M690 zoom operating microscope was used for each procedure. No filters were used. The Humphrey visual field equipment was employed to determine threshold retinal sensitivity at predetermined loci above and below fixation in both groups. No clinically visible retinal lesions were seen in any patient. However, post-operative investigation revealed a statistically significant depression in retinal sensitivity at points most exposed to operating microscope illumination (p < 0.05). This was most noticeable following longer total operating times and in patients with the longest time intervals between lens extraction and completion of the procedure. It is concluded that operating microscope position and centration, and the position of the eye, should be adjusted to place the image of the illuminating element away from the foveola. Also retinal illumination should be kept to a minimum, particularly after an intraocular lens has been implanted.

Review of fluorescein angiograms performed in one year.

In this study 374 consecutive fundus fluorescein angiograms (FFAs) were performed on 330 patients. Of these, 165 (50%) were investigated for age related maculopathy. In only 12% did this investigation lead to an alteration in treatment. The remaining 50% of angiograms were requested for diabetic patients (15%), retinal vein occlusion (5%), tumours (6%), and various other disorders. In the diabetic patients treatment could have proceeded without FFA in 24% of patients who underwent it. Missed diagnoses corrected by angiography and areas where unnecessary angiograms were performed were identified. One interesting subgroup of eight patients with unexplained loss of central vision was identified. Careful clinical examination had failed to reveal any abnormality. FFAs were of no diagnostic value in these patients.