appearances of the eye and retina
This is sympathetic interruption of one eye. It
Ptosis: drooping eyelid
Enophthalmos: indrawing of the eye (the opposite of
Miosis: constriction of the
Anhydrosis: lack of tear production
Important causes to remember include: Pancoasts syndrome
(lung tumour of the apex of the lung), neck trauma, surgical resection.
Looks like a chalky white disc
with sharply defined margins. There are many causes, but 3 common
causes to remember include:
Occlusion of the
retinal artery, e.g. in Giant Cell Arteritis
This is oedema of the optic disc. In some
pictures the disc can look "3 dimensional," the same shape as a red
blood cell. There is blurring of the disc margins, the disc may be pink
or red, there may be dilatation of the veins, and flame haemorrhages
may develop. Again there are many causes, but ones to remember include:
Increased CSF pressure, for example a space
Retinal vein obstruction
The nerve innervation of the eye can be remembered by the fake chemical
equation: LR6 SO4 AO3. This stands for lateral rectus cranial nerve
(CN) 6, superior oblique CN 4, All Others CN 3.
CN 6 Palsy
The eye is medially deviated and
CN 4 Palsy
Diplopia maximal when the eye looks downwards and inwards.
CN 3 Palsy
The eye at rest looks
down and out (due to the overriding influence of the lateral rectus and
superior oblique). The eye can not move upwards, downwards or inwards.