Absolute filling defects of the optic disc in fluorescein angiograms in glaucoma a retrospective clinical study

Background: Analysis of clinical importance of the size of filling defects in fluorescein angiograms in primary open-angle glaucoma (POAG), normal-ten sion glaucoma (NTG), ocular hypertension and subjects with physiological ex cavations in comparison to visual field loss, optic nerve head morphology a nd hemodynamics. Patients and Methods: 75 patients (POAG, NTG, ocular hypertension) and 10 h ealthy subjects with physiological excavations were included in this study. In digitized video fluorescein angiograms (Scanning Laser Ophthalmoscope) the size of absolute filling defects of the optic disc was quantified in th e early venous phase and expressed by percentage of the optic disc. Visual fields were obtained by conventional static perimetry (Humphrey 24-2) and g raded in stages of glaucoma visual field defects (Aulhorn I-V). Optic disc excavations were evaluated as cup-to-disc-area-ratios. Results: The filling defects correlated with the visual-field loss stages o f Aulhorn and the visual field indices MD (mean deviation), PSD (pattern st andard deviation) and CPSD (corrected pattern standard deviation). There wa s no correlation with the index SF (short-term fluctuation) and with system ic hemodynamics (blood pressure, perfusion pressure) or the IOP. Absolute f illing defects correlated with the cup-to-disc-area-ratio in NTG. The absol ute filling defects were larger in patients with glaucoma (POAG, NTG) in co mparison to patients without glaucomatous visual field loss (ocular hyperte nsion, glaucoma-like discs). No difference of filling defects was found in the glaucoma group (POAG, NTG). Patients with NTG had larger excavations an d lower systolic blood pressures than patients with POAG. Conclusion: The size of fluorescein filling defects may be useful as a para meter for the evaluation of an ischemic lesion of the optic nerve head. Abs olute filling defects may differentiate POAG from ocular hypertension and N TG from glaucoma-like discs without field defects. The results support the hypothesis that in POAG and NTG disturbances of the circulation result in s imilar filling defects of the optic disc and visual field loss.