The aim of this investigation was to correlate the clinical and histological findings in 85 consecutive patients with temporal arteritis. Particular attention was given to a possible correlation between optic nerve involvement and the presence of giant cells upon histological examination. Severe ischemia as in anterior ischemic optic neuropathy and central retinal arterial occlusion was presented in 37 patients (43%). Giant cells were definitely observed in 32 biopsy specimens (37.6%) and suspected in 11 additional specimens (13%): In 42 specimens (49.3%) no giant cells were present. Our study showed no correlation between the occurrence of severe optic nerve involvement and the histological findings with regard to giant cells. Statistical evaluation also failed to show a significant correlation between the frequency of pain and jaw claudication and the respective histological findings regarding giant cells. In the biopsy specimen of one patient, numerous eosinophilic granulocytes had infiltrated the vessel wall.