Abstract
Purpose: :
Frequency doubling technology perimetry (FDT) has been used to assess visual function in patients with neuro-ophthalmic abnormalities of the anterior and posterior visual pathways. Initial reports suggested that FDT is less accurate assessing defects of the posterior visual pathway. In this study, we compared Humphrey Matrix FDT to standard automated perimetry (SAP) in the assessment of pre- and post-chiasmal disease.
Methods: :
The charts of all patients with neuro-ophthalmic disease, involving the anterior (n=27) and posterior (n=9) visual pathways, tested with both Humphrey Matrix FDT (30-2) and Humphrey Visual Field Analyzer (30-2 SITA standard) from July 2006 to November 2008, were retrospectively reviewed. Involved eyes of unilateral disorders were included; the better and worse eyes were alternated in bilateral disease. Similarity between the tests were numerically graded 1 (poor), 2 (fair), and 3 (good) for total (TD) and pattern deviation (PD) plots. Additionally, the extent of defects were compared, with more extensive field loss defined as 5 or more abnormal test locations at P < 0.5%. Spearman coefficient was calculated for both mean deviation (MD) and pattern standard deviation (PSD).
Results: :
Etiologies included compressive lesions (n= 11), NAION (n= 5), stroke (n= 4), IIH (n=3), optic nerve drusen (2), and other (n= 11). The average similarities between the FDT and SAP for PD in anterior and posterior disease were 2.31 and 2.44 (p = 0.44, paired T-test); and for TD were 2.46 and 2.5, respectively (p = 0.29). The extent of defect was same in 55% on PD and 66% on TD. Spearman coefficient for anterior and posterior disease for MD was 0.86 and 0.93, and for PSD was 0.78 and 0.63, respectively.
Conclusions: :
Although originally developed for glaucomatous field defects, the Humphrey Matrix perimeter has reasonable correlation to SAP in anterior and posterior pathway disease. Our series, which uses 30-2 field analysis, demonstrates fair to good correlation between SAP and FDT in both anterior and posterior neuro-ophthalmic disease. This suggests that the poor correlation with earlier versions of FDT was due to technical aspects of the perimeter, and not due to differing aspects of visual function being tested by FDT and HVF.
Keywords: visual fields • neuro-ophthalmology: diagnosis