These can occur in

i) normal eyes
ii) eyes with glaucoma

It is not known what proportion of eyes with disc haemorrhages do not have glaucoma. My clinical experience suggests that the majority of patients with disc haemorrhage have glaucoma and the optic disc haemorrhage is often associated with loss of visual field.  The Blue Mountain Study found optic disc haemorrhages in 1.4% of the supposedly normal population (but see below).  Optic disc haemorrhages have been recorded in 4-20.5% of patients with glaucoma.

Ocular coherence tomography has demonstrated optic disc haemorrhages  associated with thinning of the retinal nerve fibre layer in otherwise apparently eyes with normal optic discs and visual fields. This implies that optic disc haemorrhage in some patients may be an indicator of early loss of the retinal ganglion cell population in patients with pre-perimetric glaucoma (glaucoma without field loss) Ophthalmology 2008; 115;2132-2140