The authors examined 50 untreated open angle glaucoma patients to determine if there was an association between the level of glaucomatous damage and documented risk factors. In this study the authors measured the extent of morphologic and functional glaucomatous damage along with other parameters of ocular blood flow. Any patient with diabetes, untreated or unstable hypertension, hypercholesterolemia, drug or alcohol abuse, significant cataract, narrow angle, secondary glaucoma or smoker were excluded. Intraocular pressure (IOP) was measured using Goldmann applanation tonometry at three time intervals throughout the day. Blood pressure and corneal temperature were recorded. Ocular pulse amplitude was assessed using the Pascal: choroidal blood flow and retinal vessels were analysed using the Retinal Vessel Analyser. Visual fields and optical coherence tomography (OCT) of the retinal nerve fibre layer thickness were also measured. The authors found that more advanced functional glaucomatous damage shown in increased mean deviation on visual fields was associated with lower ocular perfusion pressure and increased IOP variability in untreated patients. More advanced morphologic glaucomatous damage represented by thinner retinal nerve fibre layer (RNFL) was associated with lower blood flow and high IOP in untreated patients. The authors conclude that IOP and perfusion parameters seem to contribute in part to the morphologic and functional glaucomatous damage in untreated primary open angle glaucoma (POAG) patients.