Correlation between Confocal Scanning Laser Ophthalmoscopy and Scanning Laser Polarimetry in Open Angle Glaucoma

PURPOSE: To correlate the findings of confocal scanning laser ophthalmoscopy and scanning laser polarimetry in diagnosed cases of glaucoma with established visual field defects. METHODS: A total of 53 diagnosed cases of primary open angle glaucoma that had at least two recorded of IOP more than 21 mm Hg on Goldmann applanation tonometry, open angles on gonioscopy and glaucomatous visual field defects on automated perimetry, were examined by confocal scanning laser ophthalmoscopy (HRT-II) and scanning laser polarimetry (GDx-NFA), in random order. RESULTS: The number on GDx advanced analysis had a significant (p < 0.05) correlation with the rim area (r = -0.279; p = 0.043), cup area (r = 0.311; p = 0.023) and the vertical cup: disc ratio (r = 0.376; p = 0.006). The correlation between HRT-II stereometric parameters and GDx advanced analysis parameters was significant (p < 0.05) for more parameters targeting the inferior pole of the disc than the superior pole. Numerically, the worst values of GDx parameters were associated with a worse result on Moorfields regression analysis, but there was poor agreement between the diagnostic labels like within or outside normal limits as obtained on GDx and HRT-II. CONCLUSIONS: Nerve fiber loss as detected on GDx correlates well with topographic optic nerve head changes as measured with the HRT-II. However, automated diagnosis on the two machines showed poor agreement.