Clinical Clues & Presenting Problems Flashcards

Question

What is the site of a lesion for a homonymous quadrantinopia?

Answer 1

"PITS" Parietal inferior, temporal superior When plotting quadrantanopia, the segment points towards the site and location of the lesion

Answer 2

Pupillary constriction is mediated by the parasympathetic nervous system and is called miosis ``` Horners syndrome Argyll Robertson pupil (prostitutes pupil; accommodates but won't react) Pontine lesion (bilateral) Opioids Pilocarpine drops Elderly ```

Answer 3

Pupillary dilatation is mediated by the sympathetic nervous system ``` Mydriatic drops or atropine poisoning Third nerve lesion Adie's pupil (decreased reactivity) Post trauma, deep coma, cerebral death Amphetamine or glutethimide overdose Cocaine, anxiety Iritis Anticholinergic drugs ```

Answer 4

This refers to a dilated pupil with virtually no reaction to light, a slow reaction to accommodation and absent ankle reflexes. Other tendon reflexes may also be absent

Answer 5

This refers to partial ptosis; constricted pupil, apparent enophthalmos, decreased sweating over the ipsilateral face (but only when the lesion is below the carotid bifurcation); elevation of the lower lid; conjunctival injection

Answer 6

The clue is the location of the anhidrosis If sweating is absent from the face, torso and arm then this is a CENTRAL lesion - stroke, syringomyelia, multiple sclerosis, tumour or encephalitis If sweating is absent from the face only then this is a PRE-GANGLIONIC lesion - Pancoast's tumour, thyroidectomy, trauma, cervical rib If there is no anhidrosis then this is a POST-GANLIONIC lesion - carotid artery dissection, carotid aneurysm, cavernous sinus thrombosis, cluster headache (the C's)

Answer 7

This is also known as Wallenberg's syndrome. It is due to vertebral or posterior inferior cerebellar artery (PICA) thrombosis. The patient presents with vertigo, Horner's syndrome, ipsilateral V (pain and temperature loss), IX and X nerve palsies, ipsilateral cerebellar signs and contralateral loss of pain and temperature over the trunk and limbs.

Answer 8

``` Complete ptosis (if lesion is complete) Eye "down and out" Dilated pupil unreactive to light (consensual response intact in the unaffected pupil) or accommodation (sympathetic response is mediated by the second nerve) ```

Answer 9

Central lesion: brainstem infarct, tumour Peripheral lesion: aneurysm (usually on posterior communicating artery), tumour causing raised ICP (dilated pupil occurs early), infarction (typically in diabetics - pupil is spared because the inner fibres control pupillary dilatation)

Answer 10

This produces diplopia maximum when the eyes looks "down and in", tilting the head to the side of the lesion results in a failure of the affected eye to intort. Supplies the superior oblique (LR6 SO4) Most common cause is a head injury, but can be idiopathic. May be associated with a IIIrd nerve palsy, but rarely may occur as an isolated defect due to a lesion of the contralateral cerebral peduncle (the IV nerve crosses after exiting the brainstem)

Answer 11

This produces failure of lateral eye movement and diplopia. Bilateral - Wernicke's encephalopathy, mononeuritis multiplex, trauma with raised ICP Unilateral - central (vascular, tumour), peripheral disease (e.g. trauma), idiopathic NB - myasthenia and thyroid eye disease can cause "pseudo" 6th nerve palsies

Answer 12

This is an alternation between slow phase drift followed by rapid corrective saccade in the opposite direction It can be horizontal, conjugate (both eyes move together), disconjugate or vertical

Answer 13

``` Brainstem lesions especially in the medulla Vestibular lesions Cerebellar lesion Phenytoin and other drugs Alcohol intoxication ```

Answer 14

``` Dysconjugate means that the eyes move in opposite directions or that only one eye is affected. Internuclear ophthalmoplegia (INO) due to lesion of the median longitudinal fasciculus is the classic cause of dysconjugate jerk horizontal nystagmus. ``` Here is nystagmus of the abducting eye with failure of adduction of the eye on the affected side. If in a young patient with bilateral involvement, multiple sclerosis is almost always the cause; in the elderly consider brainstem infarction NB - the eye that fails to adduct tells you which side the lesion is on

Answer 15

Brainstem lesion - upgaze nystagmus suggests a lesion in the midbrain or upper pons, or Wernicke's encephalopathy - downgaze nystagmus suggests a foramen magnum lesion, cerebellar degeneration or Wernicke's encephalopathy Toxic - e.g. alcohol or pehnytoin

Answer 16

Decreased macular vision, e.g. albinism | Congenital

Answer 17

``` Senile ptosis Myasthenia gravis Myotonic dystrophy Facioscapulohumeral dystrophy Ocular myopathy Thyrotoxic myopathy Botulism Snake bite ```

Answer 18

Constricted pupils - Horner's syndrome, tabes dorsalis | Dilated pupils - 3rd nerve palsy

Answer 19

Midbrain lesion

Answer 20

``` Grave's disease Cavernous sinus thrombosis (associated with chemosis and painful ophthalmoplegia) Carotid-cavernous fistula Tumour (benign or malignant) Capillary haemagnioma Cellulitis of the eye Sarcoidosis Neurofibromatosis ```

Answer 21

Central (pons, medulla and upper cervical cord) - vascular, tumour, syringobulbia (increasing cavitation of the central pons and medulla) Peripheral (posterior fossa) - aneurysm, skull base tumour Trigeminal ganglion (petrous temporal bone, can also affect CN VI in Gradanigo's syndrome) - meningioma, fracture of the middle fossa Cavernous sinus (associated with III, IV and VI palsies) - aneurysm, thrombosis, tumour Other systemic problems - Sjogrens syndrome, SLE

Answer 22

Palatal myoclonus is pathognomonic of hypertrophic olivary degeneration involving a lesion in the triangle of Guillain and Mollaret causing hypertrophy of the inferior olivary nucleus

Answer 23

This is essentially asking for causes of mixed upper and lower motor neuron signs Subacute combined degeneration of the cord (B12 deficiency causes peripheral neuropathy hence absent ankle jerks, but also damage to the CST causing upgoing plantars) Tabes dorsalis (tertiary syphilis) Freiderich's ataxia Conus medullaris lesion Motor neurone disease (usually wasting and fasciculations + brisk reflexes) Diabetes (peripheral neuropathy + CVA)

Answer 24

Trigeminal neuralgia (NB exclude multiple sclerosis, meningioma) and post herpetic neuralgia Paratrigeminal syndrome (severe retro-orbital pain with ipsilateral ptosis and meiosis) Superior orbital fissure syndrome (retro-orbital boring pain with paresis of cranial nerves III, IV, V and VI Cluster headaches (severe, focal pain of rapid onset, usually in males with tearing and rhinorrhoea) Temporal arteritis (usually in patients >50 years with an elevated ESR, anaemia, fevers and fatigue). Strong association with PMR Temporomandibular arthritis and diseases of the sinuses, teeth and ears Glaucoma Aneurysm of internal carotid or posterior communicating arteries Atypical facial pain