Intravitreal bevacizumab has been associated with significant early functional and anatomic improvements in macular edema. The authors of a recent prospective, nonrandomized, interventional study evaluated the early rate of change of best-corrected visual acuity, central retinal sensitivity, neuroretinal and choroidal thickness in patients with macular edema after injecting 1.25 mg/0.05 ml of intravitreal bevacizumab in 37 consecutive eyes that were afflicted.
For all eyes, BCVA, central retinochoroidal thickness on standardized A-scan, central retinal thickness and central retinal sensitivity, recorded with a spectral scanning laser ophthalmoscope optical coherence tomography/microperimeter device, were evaluated at baseline and at seven, 15, 30, 37, 45 and 60 days after initial treatment. During that time, patients received two intravitreal bevacizumab injections at a one-month interval.
The authors found that a significant yet non-related improvement of BCVA and retinal sensitivity occured after one- and two-month follow-ups. Anatomic improvement only involved the neuroretina; significant changes in central choroidal thickness were not detected.
(J Cataract Refract Surg 2009;35:1358-62)
Koller T, Mrochen M, Seiler T
Bad News for the Monocular Drug Trial
A new study has provided evidence that the monocular drug trial is a poor predictor for determining the long-term intraocular pressure reduction that comes with using latanoprost. The authors of the study used a prospective, randomized, investigator-masked trial to evaluate 26 subjects with ocular hypertension or open-angle glaucoma with the goal of finding a relationship between short- and long-term IOP reduction, with the coefficient of determination (the square of the Pearson correlation coefficient, r) as the measure of association.
Subjects attended five study visits: two on no IOP-lowering therapy, one on monocular therapy with latanoprost and two on bilateral therapy. The monocular trial eye was randomly selected, and study personnel making IOP measurements were masked to randomization. The following parameters were calculated: the unadjusted IOP change (IOP in the randomized eye at the first on-treatment visit minus IOP in the same eye at the initiation of the monocular trial); the adjusted IOP change (the unadjusted IOP change minus the comparable IOP change in the untreated fellow eye between the same two visits); and the long-term IOP change (the difference of the mean of the two on-treatment IOP values during bilateral use and the mean of the two pretreatment IOP values).
Results showed that mean long-term IOP reduction after latanoprost therapy was -3.4 ±2.4 mmHg in both first- and second-treated eyes (p<0.0001). The mean unadjusted IOP reduction in the monocular trial eye was -3.1 ±3.4 mmHg; the correlation between the unadjusted IOP change and the long-term IOP change was weak to moderate (coefficient of determination 0.325). The mean adjusted IOP reduction was -2.8 ±4.3 mmHg; the correlation between the adjusted IOP change and the long-term IOP change was shown to be weak to moderate (coefficient of determination 0.279).