oreosec.blogg.se - Cough reflex vs gag reflex nerve

Efferent defect (affected pupil is persistently dilated, whilst other is reactive to light being shone in either eye) = CN3 lesion.

pupils are symmetrical but when light is shone in the affected eye, neither pupil constricts) = CN2 (optic nerve) lesion Observe for direct and consensual papillary constriction. Shine the light at each pupil in turn from about 45°.

Direct and consensual papillary reflexes: in a dimmed room, ask the patient to hold an open hand between their eyes and focus on a distant point in the room.

Pupils should constrict and eyes should converge.

Accommodation: ask the patient to focus on a distant object, then hold your finger close to their face and ask them to focus on it.

Map each of their blind spots against your own ( large blind spot = papilloedema). Now move the pin horizontally towards the periphery in each direction and to tell you when it disappears. Check they can see it as red in the middle ( central scotoma = optic nerve lesion).

Blind spots (offer to test): while the patient keeps both eyes open and focussed on you, hold a red pin mid-distance between you.

Left/right homonymous hemianopia = contralateral optic tract/radiation lesion, or occipital cortex if macular sparing is present.

Bitemporal hemianopia = optic chiasm compression.

Mononuclear field loss = intra-ocular pathology or ipsilateral optic nerve lesion.

Test both eyes individually, comparing their fields with yours. Move in a diagonal direction into each of the four quadrants. Ask them to tell you when they can see it. Select a white visual fields pin and bring it in from the periphery, keeping it at mid-distance between you and the patient.

Ask them to stay focussed on your open eye. Visual fields: ask the patient to cover one eye with their palm and close your eye on the same side (without using your palm if you can).identification of only one moving hand when both are moving = contralateral parietal lesion.) Ask them to point at the hand(s) which you are opening and closing. Visual inattention: while the patient keeps both eyes open and focussed on you, hold out your hands in each of their outer visual fields.Sit the patient 1 metre directly in front of you with both your eyes at the same level