Faculty Bibliography

OBJECTIVE: The purpose of this document is to summarize and evaluate the effectiveness of new automated perimetry tests and algorithms in diagnosing glaucoma and detecting disease progression. METHODS: A literature search on automated perimetry retrieved over 300 citations from 1994 to 2001, of which 71 were selected as relevant to this assessment. The quality of the evidence obtained from these studies was assessed by the methodologist. RESULTS: The four automated perimetry techniques described in this assessment are short wavelength automated perimetry (SWAP), frequency doubling technology perimetry (FDT), high-pass resolution perimetry (HPRP), and motion automated perimetry (MAP). The algorithms described are Swedish interactive threshold algorithm (SITA) and SITA fast. With the exception of SWAP, these techniques and algorithms reduce testing time and inconsistent patient performance when compared with conventional full threshold testing. CONCLUSIONS: Short wavelength automated perimetry detected visual field loss earlier than standard threshold automated perimetry, with a sensitivity and specificity of about 88% and 92% respectively. However, it is a lengthy, demanding test, is sensitive to media opacities, and has a greater magnitude of long-term fluctuation compared with standard threshold automated perimetry, which make it difficult to assess disease progression accurately. When compared to standard threshold automated perimetry, FDT perimetry showed sensitivity and specificity greater than 97% for detecting moderate and advanced glaucoma, and sensitivity of 85% and specificity of 90% for early glaucoma. As FDT perimetry has a short testing time and is resistant to blur and pupil size, it may be a useful screening tool. In a longitudinal study, high-pass resolution perimetry was more effective than standard threshold automated perimetry in monitoring progressive glaucomatous loss, detecting progression at a median of 12 months earlier in 54% of patients studied. Motion automated perimetry demonstrated usefulness in detecting early glaucomatous visual loss in a longitudinal study. Studies on SITA demonstrated greater sensitivity and reproducibility and less intertest variability when compared to standard full threshold testing and a 50% reduction in testing times. A study comparing standard full threshold, SITA, and SITA fast found a sensitivity of 95% for the first two techniques and 93% for SITA fast. Long-term follow-up studies are needed to assess the ability of these techniques to detect progression of glaucoma over time.

PURPOSE: To determine if optical coherence tomography (OCT) measurements of nerve fiber layer (NFL) thickness can be used to predict the presence of visual field defects (VFD) associated with glaucoma. DESIGN: Quota-sampled, cross-sectional study. METHODS: Retrospective study of OCT NFL thickness measurements in 276 eyes of 276 subjects. All persons received OCT NFL thickness analysis; 136 eyes underwent frequency-doubling technology (FDT) perimetry; and 140 eyes underwent Swedish interactive threshold algorithm (SITA) perimetry. We defined a parameter called NFL(50), which is the NFL thickness value at which there was a 50% likelihood of a VFD with either SITA or FDT perimetry. We evaluated the use of NFL(50). RESULTS: The mean NFL thickness with (n = 68) and without (n = 68) a VFD in the FDT group was 93.2 microm +/- 22.6 and 108.4 microm +/- 14.1, respectively. The mean NFL thickness with (n = 70) and without (n = 70) a VFD in the SITA group was 78.9 microm +/- 24.8 and 103.0 microm +/- 18.0, respectively. The FDT mean NFL(50) value was 98.5 microm. The SITA mean NFL(50) value was 87.0 microm. The area under the receiver operator characteristic (AROC) curve for mean NFL was 0.73, and the positive predictive value (PPV) for FDT mean NFL(50) was 72.2%. For SITA mean NFL, the AROC was 0.79 and the PPV for NFL(50) was 77.2%. CONCLUSION: Nerve fiber layer thickness analysis using OCT may be clinically useful in identifying subjects who have visual field loss. However, the PPV suggests that OCT may need higher resolution and better reproducibility to enhance its sensitivity and specificity for population screening.

OBJECTIVE: To compare bimatoprost with timolol maleate in patients with glaucoma or ocular hypertension. METHODS: In 2 identical, multicenter, randomized, double-masked, 1-year clinical trials, patients were treated with 0.03% bimatoprost once daily (QD) (n = 474), 0.03% bimatoprost twice daily (BID) (n = 483), or 0.5% timolol maleate BID (n = 241). MAIN OUTCOME MEASURES: Diurnal intraocular pressure (IOP) at 8 AM, 10 AM, and 4 PM and safety variables (IOP was also measured at 8 PM at selected sites). RESULTS: Bimatoprost QD provided significantly lower mean IOP than timolol at every time of the day at each study visit (P<.001). This was also true for bimatoprost BID at most time points, but the efficacy was not as good as that of the QD regimen. At 10 AM (peak timolol effect) at month 12, the mean reduction in IOP from baseline was 7.6 mm Hg (30%) with bimatoprost and 5.3 mm Hg (21%) with timolol (P<.001). A significantly higher percentage of patients receiving bimatoprost QD (58%) than timolol (37%) achieved IOPs at or below 17 mm Hg (10 AM, month 12; P<.001). The most common adverse effect with bimatoprost was hyperemia (significantly higher with bimatoprost QD than timolol; P<.001). CONCLUSIONS: Bimatoprost QD provides sustained IOP lowering superior to timolol or bimatoprost BID and achieves low target IOPs in significantly more patients.

Glaucoma, a leading cause of blindness worldwide, is a chronic neurodegenerative disorder. Patients with glaucoma may require long-term administration of intraocular pressure (IOP)-lowering medications. These medications belong to several classes of molecules including beta-adrenergic blockers, cholinergic agents, alpha-adrenergic agonists, carbonic anhydrase inhibitors and ocular hypotensive lipids. Most adverse effects associated with IOP-lowering medications are mild and ocular in nature; however, several of them are associated with systemic risks as well as serious ocular effects, especially following chronic use. The following review discusses the acute and long-term effects of commonly used IOP-lowering medications.

PURPOSE: To report a case of herpes simplex virus reactivation after starting bimatoprost treatment for glaucoma. DESIGN: Interventional case report. METHODS: A 66-year-old woman had a herpes simplex keratouveitis reactivation that occurred within 1 month after starting bimatoprost. The herpes simplex had been inactive for more than 10 years. RESULTS: Bimatoprost and prednisolone acetate 0.12% were discontinued; oral acyclovir, ofloxacin, and betaxolol 0.25% were initiated. Two weeks later, prednisolone acetate 1% was added. The reactivation resolved, and 1 month later, the best corrected visual acuity improved to 20/40. CONCLUSION: Caution should be used in prescribing bimatoprost for patients with a history of herpes simplex virus keratitis.