Ординатура / Офтальмология / Английские материалы / Illustrated Tutorials in Ophthalmology Kanski, Bolton 2001

Anatomy of third nerve

Oculomotor nucleus

Pituitary gland

Red nucleus

Carotid artery

Cavernous sinus

Pons

III nerve

Basilar artery

Applied anatomy of pupillomotor nerve fibres

Blood vessels on pia mater supply surface of the nerve including pupillary

fibres ( damaged by compressive lesions )

Vasa nervorum supply part of nerve but not pupillary fibres ( damaged by medical lesions )

Pupillary fibres lie dorsal and peripheral

Signs of right third nerve palsy

Hess chart of right third nerve palsy

•Contraction of right chart and expansion of left

•Right chart - underactions of all muscles except lateral rectus and superior oblique

•Left chart - overactions of all muscles except medial rectus and inferior oblique

Important causes of isolated third nerve palsy

Idiopathic - about 25%

Vascular disease - hypertension, diabetes

Signs of right fourth nerve palsy

• Right overaction on left gaze

Positive Bielschowsky test in right fourth nerve palsy

Hess chart of right fourth nerve palsy

•No significant difference in chart size

•Upward deviation of right fixation spot on inner chart (hypertropia)

•Downward deviation of left fixation spot on inner chart

•Right chart - underaction of superior oblique and overaction of inferior oblique

•Left chart - overaction of inferior rectus and underaction of superior rectus