Neurology Short Case Flashcards
Causes of Horner’s syndrome (6)
- Carcinoma of lung apex (usually SCC)
- Neck - thyroid malignancy, trauma
- Carotid arterial lesion - carotid aneurysm or dissection, peri-carotid tumour, cluster headache
- Brainstem lesion - lateral medullary syndrome, syringobulbia, tumour
- Retro-orbital lesions
- Syringomyelia (rare)
Causes of anosmia (bilateral) (7)
- Upper respiratory tract infection (most common)
- Meningioma of the olfactory groove (late)
- Ethmoid tumours
- Head trauma (including cribriform plate fracture)
- Meningitis
- Hydrocephalus
- Congenital - Kallman’s syndrome (hypogonadotrophic hypogonadism)
Causes of anosmia (unilateral) (2)
- Meningioma of the olfactory groove (early)
2. Head trauma
Causes of absent light reflex but intact accomodation reflex (4)
- Midbrain lesion (eg. Argyll Robertson pupil)
- Ciliary ganglion lesion (eg. Adie’s pupil)
- Parinaud’s syndrome
- Bilateral anterior visual pathway lesions (bilateral afferent pupil deficits)
Causes of absent convergence but intact light reflex (2)
- Cortical lesion (eg. cortical blindness)
2. Midbrain lesions (rare)
Causes of constricted pupils (6)
- Horner’s syndrome
- Argyll Robertson pupil
- Pontine lesion (often bilateral, but reactive to light)
- Narcotics
- Pilocarpine drops
- Old age
Causes of dilated pupils (6)
- Mydriatics, atropine poisoning or cocaine
- Third nerve lesion
- Adie’s pupil
- Iridectomy, lens implant, iritis
- Post trauma, deep coma, cerebral death
- Congenital
Cause and signs (5) of Adie’s syndrome
Cause: lesion in the efferent parasympathetic pathway
Signs:
- Dilated pupil
- Decreased or absent reaction to light (direct and consensual)
- Slow or incomplete reaction to accomodation with slow dilation afterwards.
- Decreased tendon reflexes
- Patients are commonly young women
Causes of Argyll Robertson pupil (4)
Cause: lesion of the iridodilator fibres in the midbrain
- Syphilis
- Diabetes mellitus
- Alcoholic midbrain degeneration (rarely)
- Other midbrain lesions
Signs of Argyll Robertson pupil (4)
- Small, irregular, unequal pupil
- No reaction to light
- Prompt reaction to accomodation
- If tabes associated, decreased reflexes
Features of papilloedema (6)
- Optic disc swollen without venous pulsation
- Acuity normal (early)
- Colour vision normal
- Large blind spot
- Peripheral constriction of visual fields
- Usually bilateral
Features of papillitis (6)
- Optic disc swollen (in retrobulbar neuritis and old papillitis the optic disc becomes pale)
- Acuity poor
- Colour vision affected (particularly red desaturation)
- Large central scotoma
- Pain on eye movement
- Onset usually sudden and unilateral
Causes of papilloedema (7)
- Space - occupying lesion (causing raised intracranial pressure) or a retro-orbital mass
- Hydrocephalus (associated with large ventricles)
- Idiopathic intracranial hypertension
- Hypertension (grade IV)
- Central retinal vein thrombosis
- Cerebral venous sinus thrombosis
- High cerebrospinal fluid protein level - Guillain-Barre syndrome
Causes of hydrocephalus (2)
- Obstructive (block in the third ventricle, aqueduct or outlet to fourth ventricle - eg. tumour)
- Communicating
- increased formation - choroid plexus papilloma
- decreased absorption - tumour causing venous compression, subarachnoid space obstruction from meningitis
Causes of idiopathic intracranial hypertension (6)
- Idiopathic
- Contraceptive pill
- Addison’s disease
- Drugs - nitrofurantoin, tetracycline, vitamin A, steroids
- Lateral sinus thrombosis
- Head trauma
Causes of optic atrophy (5)
- Chronic papilloedema or optic neuritis
- Optic nerve pressure or division
- Glaucoma
- Ischemia
- Familial - retinitis pigments, Leber’s disease, Friedreich’s ataxia
Causes of optic neuropathy (6)
- Multiple sclerosis
- Toxic - ethambutol, chloroquine, nicotine, alcohol
- Metabolic - vitamin B12 deficiency
- Ischaemia - diabetes mellitus, temporal arteritis, atheroma
- Familial - Leber’s disease
- Infective - infectious mononucleosis
Causes of cataract (6)
- Old age (senile cataract)
- Endocrine - diabetes mellitus, steroids
- Hereditary or congenital - dystrophia myotonica, Refsum disease
- Ocular disease - galucoma
- Irradiation
- Trauma
Causes of ptosis with normal pupils (9)
- Senile ptosis (common)
- Myotonic dystrophy
- Fascioscapulohumeral dystrophy
- Ocular myopathy eg. mitochondrial myopathy
- Thyrotoxic myopathy
- Myasthenia gravis
- Botulism, snake bite
- Congenital
- Fatigue
Causes of ptosis with constricted pupils (2)
- Horner’s syndrome
2. Tabes dorsalis
Cause of ptosis with constricted pupils (1)
- Third nerve lesion
Clinical features of a third nerve palsy (3)
- Complete ptosis (partial ptosis with incomplete lesions)
- Divergent strabismus (eye ‘down and out’)
- Dilated pupil unreactive to direct or consensual light and unreactive to accomodation
Central causes of third nerve palsy (5)
- Vascular (brainstem infarction)
- Tumour
- Demyelination
- Trauma
- Idiopathic
Peripheral causes of third nerve palsy (4)
- Compressive lesions (next card)
- Infarction - diabetes mellitus, arteritis (pupil usually spared)
- Trauma
- Cavernous sinus lesions