[Optic Disk Drusen: Historical and Up-To-Date Aspects].

Optic disc drusen are an important differential diagnosis in the diagnostic evaluation of a prominent optic nerve head. Drusen of the optic disc occur in 0.34 to 2.4 % of human individuals and manifest themselves bilaterally in three of four cases. Drusen are found six times more often within histological sections than on funduscopic examination. It is known that optic disc drusen can occur in familial clusters without any other pathological ophthalmic findings. They can also be associated with retinitis pigmentosa, or with the Joubert or Alagille syndromes. Non-invasive diagnostic tools include fundus-autofluorescence (AF), optical coherence tomography (OCT) and ultrasound. Drusen of the optic nerve head are asymptomatic in most cases, though transient ischemia can lead to transient visual impairment. In particular, superficial drusen can lead to profound visual field defects in adulthood. Regular ophthalmological follow-up examinations with tonometry and perimetry are recommended for the early detection of visual field defects. Radial optic neurotomy (RON) seems to be a therapeutic option in patients with acute deterioration of the visual field.