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The macular threshold protocol of the Humphrey visual field analyzer: A superior functional outcome of intravitreal bevacizumab for the treatment of neovascular age-related macular degeneration

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To evaluate the decibel loss on the Macular threshold protocol of the Humphrey visual field as a reliable functional outcome of the intravitreal bevacizumab treatment. Thirteen patients were evaluated at baseline and on the week 6 for best corrected visual acuity, optical coherence tomography central macular thickness and decibel loss on Macular threshold protocol of the Humphrey visual field after 1.25 mg intravitreal injection of bevacizumab. The outcomes were analyzed separately and in correlation using the Wilcoxon signed ranks test. The improvement of the optical coherence tomography and the Macular threshold protocol of the Humphrey visual field from baseline to week 6 were significant with p=0.032 and p=0.003, respectively. The visual acuity did not show a significant improvement. The correlation of the visual acuity and Macular threshold protocol of the Humphrey visual field was significant at baseline (p=0.041) and on week 6 (p=0.019). The Macular threshold protocol of the Humphrey visual field significantly improved despite the fact that the best corrected visual acuity did not. The Macular threshold protocol of the Humphrey visual field correlated with the visual acuities significantly. The optical coherence tomography was significant to demonstrate improvement but did not correlate with best corrected visual acuity and Macular threshold protocol of the Humphrey visual field. These findings suggest that the Macular threshold protocol of the visual field may be a more reliable tool for evaluation of global macular function after intravitreal bevacizumab treatment.
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Chapter
Visual field testing in retinal disorders is an underutilised investigation, the potential of which needs to be realised. It is one of the most readily available functional tests. Through this case-based chapter, we would like to introduce our readers to using Humphrey visual fields for both diagnosis and prognosis of various retinal diseases.
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