False negative results in glaucoma detection with Heidelberg Retina Tomograph II

Catherine Deghislage, Lidwine Van Malderen, Thierry G ZeyenDepartment of Ophthalmology, University Hospitals, Leuven, B-3000, BelgiumPurpose: To evaluate the rate of false negative results with the Heidelberg Retina Tomograph (HRT II) in a glaucoma practice.Design: Cross-sectional study.Methods: We analyzed the HRTs taken between October 2002 and October 2003 in our glaucoma clinic, and selected the patients who had a good quality image (SD < 40 µ) with a normal Moorfield’s Regression Analysis (MRA). A masked independent observer classified those patients as normal, glaucoma suspect, or glaucomatous on the basis of optic disc stereo photos (ODP) and at least 2 consecutive reliable automated perimetries. The diagnosis of glaucoma was based on a glaucomatous optic disc with a congruent, reproducible visual field defect.Results: Four hundred and fifty patients who had undergone an HRT examination were analyzed. One hundred and nine patients had an HRT classified as normal on the MRA, and a good quality image. Fifteen of those 109 patients (13.7%) were classified as glaucomatous on the basis of an abnormal ODP with corresponding visual field defect. Seven (6.4%) patients were classified as glaucoma suspect.Conclusion: Fourteen percent of glaucoma patients with glaucoma remained undetected with the HRT II Moorfield’s regression analysis as a sole means to detect glaucoma.Keywords: glaucoma detection, false negative results, Heidelberg Retina Tomograph I

Latanoprost for open-angle glaucoma (UKGTS): a randomised, multicentre, placebo-controlled trial

Background: Treatments for open-angle glaucoma aim to prevent vision loss through lowering of intraocular pressure, but to our knowledge no placebo-controlled trials have assessed visual function preservation, and the observation periods of previous (unmasked) trials have typically been at least 5 years. We assessed vision preservation in patients given latanoprost compared with those given placebo. Methods: In this randomised, triple-masked, placebo-controlled trial, we enrolled patients with newly diagnosed open-angle glaucoma at ten UK centres (tertiary referral centres, teaching hospitals, and district general hospitals). Eligible patients were randomly allocated (1:1) with a website-generated randomisation schedule, stratified by centre and with a permuted block design, to receive either latanoprost 0·005% (intervention group) or placebo (control group) eye drops. Drops were administered from identical bottles, once a day, to both eyes. The primary outcome was time to visual field deterioration within 24 months. Analyses were done in all individuals with follow-up data. The Data and Safety Monitoring Committee (DSMC) recommended stopping the trial on Jan 6, 2011 (last patient visit July, 2011), after an interim analysis, and suggested a change in primary outcome from the difference in proportions of patients with incident progression between groups to time to visual field deterioration within 24 months. This trial is registered, number ISRCTN96423140. Findings: We enrolled 516 individuals between Dec 1, 2006, and March 16, 2010. Baseline mean intraocular pressure was 19·6 mm Hg (SD 4·6) in 258 patients in the latanoprost group and 20·1 mm Hg (4·8) in 258 controls. At 24 months, mean reduction in intraocular pressure was 3·8 mm Hg (4·0) in 231 patients assessed in the latanoprost group and 0·9 mm Hg (3·8) in 230 patients assessed in the placebo group. Visual field preservation was significantly longer in the latanoprost group than in the placebo group: adjusted hazard ratio (HR) 0·44 (95% CI 0·28–0·69; p=0·0003). We noted 18 serious adverse events, none attributable to the study drug. Interpretation: This is the first randomised placebo-controlled trial to show preservation of the visual field with an intraocular-pressure-lowering drug in patients with open-angle glaucoma. The study design enabled significant differences in vision to be assessed in a relatively short observation period

Glaucoma medication during pregnancy and nursing

Risks that glaucoma medications pose to the fetus and neonate must be balanced against the risk of vision loss in the mother. There is no high level evidence for harmful effects on the fetus and neonate of medications used to treat glaucoma. All topical and systemic glaucoma medication should be avoided during the first trimester of pregnancy. Systemic carbonic anhydrase inhibitors, topical prostaglandin analogues and antimetabolites during surgery should be avoided absolutely. Some topical medications are deemed compatible with lactation by the American Academy of Pediatrics, however, caution should still be practiced.status: publishe

Ahmed and Baerveldt glaucoma drainage implants: long-term results and factors influencing outcome

PURPOSE: To evaluate the clinical outcome of patients who received an Ahmed or Baerveldt implant for refractory glaucoma at the University Hospitals Leuven and to identify the factors which may influence the outcome. METHODS: Retrospective study including 62 eyes with uncontrolled glaucoma, who underwent the implantation of a drainage device between January 2002 and December 2008. Criteria for complete success were an intraocular pressure (IOP) 5 mmHg, and a minimum 20% decrease in IOP compared to baseline, without additional medications at 2 consecutive visits after 3 months. Qualified success was defined as the same criteria with additional medications. If these criteria were not met, if additional glaucoma surgery was needed, or if the eye became phtitic, the case was classified as failure. Other outcome measurements were IOP reduction, additional glaucoma medications at the last follow-up, visual acuity, visual field, and complications. RESULTS: Over a mean follow-up period of 25 +/- 21,91 months, the mean intraocular pressure decreased from 27,98 +/- 6,5 mmHg to 15,2 +/- 5,87 mmHg (mean drop of 45%) at the last visit. Overall success (i.e. with or without medication) was 67.3%. Visual acuity improved or remained unchanged in 52/62 (83,9%) of patients. Eight patients (12,9%) had complications with significant visual loss (at least two Snellen lines worse) and five patients (8,1%) needed further surgery due to complications. No significant outcome predictors could be established. CONCLUSION: Ahmed and Baerveldt implants are a safe and effective procedure for lowering the IOP in the management of refractory glaucoma.status: publishe

Stripping of Descemet's membrane while refilling the anterior chamber

No abstract available.status: publishe

The iStent trabecular micro-bypass stent: a case series

PURPOSE: To evaluate the safety and effectiveness of a trabecular micro-bypass stent, the iStent (Glaukos, USA), for reduction of intraocular pressure in patients with open angle glaucoma. METHODS: In this prospective case series, ten eyes of eight patients underwent a gonioscopically-guided implantation of an iStent. Six eyes underwent combined surgery: cataract surgery followed by iStent implantation, and the remaining four eyes underwent iStent implantation only. The primary outcome measure was intraocular pressure and the secondary outcome measures were the reduction in number of glaucoma medications, and the number of complications. RESULTS: Mean intraocular pressure dropped from 19.6 mmHg preoperatively to 16.3 mmHg (range 12-27) after one month (p = 0.04), to 15.4 mmHg (range 8-23) after six months (p = 0.03) and 15.8 mmHg (range 9-25 mmHg) after one year (p = 0.03). There was a significant reduction in number of hypotensive medications between baseline and 12 months postoperatively from 2.7 to 1.7 medications. No vision-threatening complications were observed. CONCLUSIONS: The Glaukos iStent trabecular micro-bypass implantation is a safe procedure that is not associated with complications traditionally associated with filtering surgery. This trabecular bypass results in significant mid-term reduction of intraocular pressure as well as the number of medications.status: publishe

The safety and efficacy of glaucoma medication in the pediatric population

Topical glaucoma medications are widely used for childhood glaucoma, although little is known concerning the use of the newer glaucoma medications in this population. The majority of the references cited were extracted from PubMed. A literature review of all English language reports related to glaucoma medication in the pediatric population since 1980 was performed. Medical therapy of pediatric glaucoma contains four groups of drugs: beta-blockers (timolol and betaxolol), carbonic anhydrase inhibitors (dorzolamide), alpha2-agonists (brimonidine), and prostaglandin analogs (latanoprost). Timolol is the first choice in pediatric glaucoma. In cases with insufficient reduction of the intraocular pressure (IOP), the combination of timolol once a day and dorzolamide twice a day brings about a good control of the IOP. Both medications are effective and well tolerated. The alpha2-agonists have more and potentially serious adverse effects in children and are contraindicated for children younger than 2 years of age. Latanoprost tends to be less effective in lowering IOP in children than in adults. However, no studies are reported where latanoprost is used in monotherapy. Additional study may further delineate this drug's role in treating pediatric glaucoma. The safety profile of latanoprost in children appears excellent.status: publishe

Agreement and Accuracy of Non-Expert Ophthalmologists in Assessing Glaucomatous Changes in Serial Stereo Optic Disc Photographs

PURPOSE:: To compare the interobserver agreement in detecting glaucomatous optic disc changes using serial stereophotography between a large group of non-expert ophthalmologists and glaucoma specialists; to assess the accuracy of non-experts; to investigate whether the interobserver agreement and the accuracy of non-experts changed after a training session. DESIGN:: Masked interobserver agreement study. PARTICIPANTS:: Serial optic disc stereophotos from 40 patients with glaucoma. METHODS:: Three independent experienced glaucoma specialists (readers of the European Glaucoma Prevention Study) evaluated a set of 2 serial optic disc color stereo-slides for glaucomatous change, obtained with a delay varying from 2 to 7 years of 40 patients, masked from the temporal sequence of the slides. Each patient was graded as changed or stable by agreement of 2 of 3 of the experts (the reference standard). Thirty-seven non-expert ophthalmologists independently evaluated the same set of serial optic disc stereo-slides twice, with the second evaluation on the same day, masked from the results of the previous evaluation, after a training session on a separate slide set. MAIN OUTCOME MEASURES:: Interobserver agreement of non-experts and experts in detecting glaucomatous optic disc changes (expressed as kappa coefficient); agreement of non-experts with the reference standard (accuracy) before and after a training session. RESULTS:: The interobserver kappa coefficient (κ) of the non-experts and experts was 0.20 (95% confidence interval [CI], 0.19-0.21) and 0.51 (95% CI, 0.33-0.69), respectively (P<0.0001). The mean κ of the non-experts with the reference standard was 0.33 (95% CI, 0.27-0.39). After a training session, the interobserver agreement of the non-experts increased from 0.20 to 0.27 (95% CI, 0.26-0.28) (P<0.0001). The percentage agreement of the non-experts with the reference standard improved from 68.5% before to 71.4% after the training session (Wilcoxon signed-rank test, P=0.034). CONCLUSIONS:: The interobserver agreement of non-expert ophthalmologists in detecting glaucomatous optic disc changes using serial stereophotos was significantly lower than that of experts, which was moderate. After a training session, the interobserver agreement and the accuracy of the non-experts showed a small but statistically significant improvement. FINANCIAL DISCLOSURE(S):: The author(s) have no proprietary or commercial interest in any materials discussed in this article.status: publishe

Variability of the Standard Reference Height and its Influence on the Stereometric Parameters of the Heidelberg Retina Tomograph 3

Purpose: To investigate the variability of the standard reference height (SRH) in consecutive Heidelberg Retina Tomograph 3 (HRT3) examinations and its influence on 5 main stereometric parameters. Methods: The HRT3 results of all patients attending our glaucoma center from August to October 2007 were retrospectively reviewed. Only one eye per patient with at least 3 consecutive HRT's with a quality control label of acceptable or better was selected. A SRH difference >/=10% compared to baseline was considered as excess SRH variability. Results: A review of 641 patients yielded 150 patients (150 eyes) who met the inclusion criteria representing a total of 556 examinations. The mean total number of HRT's per patient was 3.7 (range 3-7), and the mean follow-up time was 3.5 years (range 1.4-6.7). The mean proportion of consecutive HRT3 examinations with intra-individual excess SRH variability was 46% (95%CI [40;52]), while the mean intra-individual excess SRH variability was 24% (95%CI [20;28]). The median absolute SRH difference was 8.6% (interquartile range [IQR] 3.9%-16.2%). Furthermore, 55.5%, 75.3%, 74.7%, 0.0% and 19.4% of the variability in Rim Area (RA), Rim Volume (RV), Retinal Nerve Fiber Layer (RNFL) thickness, Cup Shape Measure (CSM), and Height Variation Contour (HVC), respectively, could be attributed to SRH variability. Conclusions: There is considerable SRH variability between HRT3 examinations of the same eye and this could explain more than half of the variability of the parameters RA, RV, and RNFL. These findings indicate that changes of HRT3 parameters should be considered with caution when excess SRH variability is present.status: publishe