Medicine

Ischaemic Stroke This refers to brain ischaemia that results in neurological damage lasting > 24 hours. It occurs due to occlusion of an artery which reduces blood flow to the brain.   Embolic This is where a clot breaks off and occludes a part of the cerebral circulation. The most frequent source of emboli are clots dislodged from the left side of the heart, in patients with atrial fibrillation. These often block the middle cerebral artery (MCA). Emboli can cause single arterial blockage or ‘showers’ to multiple arteries and arterial distributions.   Thrombotic This is a stroke due to a rupture of

Parkinson’s disease This is a disease where the dopaminergic neurons in the substantia nigra are progressively lost, resulting in the development of symptoms. Parkinsonism can be drug-induced (gives rapid-onset bilateral motor symptoms)   Symptoms Tremor, described as a pill-rolling motion of thumb over fingers, which is usually worse at rest and typically improves with movement Bradykinesia – slow initiation of voluntary movements Hypertonia – increased muscle tone, which gives cogwheel rigidity in the extremities Postural instability and shuffling/festinant gait (pitched forward gait) Expressionless face (“mask-like”) Psychiatric – depression (most common symptom), dementia and psychosis Micrographia, anosmia Autonomic dysfunction (postural hypotension and

Disorders of the labyrinth   Benign Paroxysmal Positional Vertigo This is a condition which causes movement-dependent vertigo. It is seen more in elderly patients. Symptoms come on suddenly when head position is altered. It is not difficult to treat, but the symptoms do tend to recur after a few years.   Symptoms Vertigo worsened by head movement, e.g., turning in bed Each episode lasts less than 30 seconds and can make the patient feel sick/extremely dizzy Key tests A positive Dix-Hallpike manoeuvre – this reproduces vertigo and nystagmus is seen in the affected side   Management Recovery is normally spontaneous

Myasthenia Gravis This is an autoimmune disease caused by autoantibodies against nicotinic acetylcholine receptors (AchR) at the neuromuscular junction (NMJ). There can be additional antibodies against muscle-specific kinase (MuSK) protein. It is more common in women and associated with thymus hyperplasia and thymoma.   Symptoms Use dependent muscle weakness – this worsens with activity and improves with rest Weakness typically starts with eyes (ptosis, diplopia), and can spread (or generalise) to face, bulbar muscles, neck, trunk, and limbs (proximal > distal muscle weakness) Symptoms are exacerbated by infections, surgery, and some drugs, e.g., beta-blockers, lithium, certain antibiotics (ciprofloxacin, gentamicin)  

Parkinson’s disease This is a disease where the dopaminergic neurons in the substantia nigra are progressively lost, resulting in the development of symptoms. Parkinsonism can be drug-induced (gives rapid-onset bilateral motor symptoms)   Symptoms Tremor, described as a pill-rolling motion of thumb over fingers, which is usually worse at rest and typically improves with movement Bradykinesia – slow initiation of voluntary movements Hypertonia – increased muscle tone, which gives cogwheel rigidity in the extremities Postural instability and shuffling/festinant gait (pitched forward gait) Expressionless face (“mask-like”) Psychiatric – depression (most common symptom), dementia and psychosis Micrographia, anosmia Autonomic dysfunction (postural hypotension and

Myasthenia Gravis This is an autoimmune disease caused by autoantibodies against nicotinic acetylcholine receptors (AchR) at the neuromuscular junction (NMJ). There can be additional antibodies against muscle-specific kinase (MuSK) protein. It is more common in women and associated with thymus hyperplasia and thymoma.   Symptoms Use dependent muscle weakness – this worsens with activity and improves with rest Weakness typically starts with eyes (ptosis, diplopia), and can spread (or generalise) to face, bulbar muscles, neck, trunk, and limbs (proximal > distal muscle weakness) Symptoms are exacerbated by infections, surgery, and some drugs, e.g., beta-blockers, lithium, certain antibiotics (ciprofloxacin, gentamicin)  

Migraine This is a primary headache which is more common in women and can be debilitating. In a migraine, there is an increase in cerebral activity, which releases 5-HT. This activates the endothelium by binding 5-HT2 receptors causing vasodilation and sensitising nerve endings. 5-HT1D/1B activation inhibits this vasodilation and inflammation of meninges. A hallmark is that approximately a third are precipitated by an aura, a reversible sensory or motor phenomenon which develops over 5 minutes and lasts < 1 hour. These auras include changes of taste/smell, scintillating scotoma/flashing lights, dysphasia. Triggers Alcohol Menstruation Bright lights Stress Contraceptive pill Certain foods (cheese, chocolate,

Meningitis This is inflammation of the leptomeninges (pia and arachnoid mater) lining the brain. It is most commonly due to an infectious agent, which can lead to an increase in intracerebral pressure and the development of cerebral oedema. If left untreated, it can lead to hydrocephalus, hearing loss, fibrosis and death by cerebral herniation.   Causes Viruses (most common cause), e.g., enterovirus (coxsackie, echovirus), mumps, herpesviruses, measles Bacterial causes are less common but more serious In adults, the most common bacteria is N. meningitidis and S. pneumoniae In babies, group B streptococci and E. coli are common causes Symptoms Early

Meningitis This is inflammation of the leptomeninges (pia and arachnoid mater) lining the brain. It is most commonly due to an infectious agent, which can lead to an increase in intracerebral pressure and the development of cerebral oedema. If left untreated, it can lead to hydrocephalus, hearing loss, fibrosis and death by cerebral herniation.   Causes Viruses (most common cause), e.g., enterovirus (coxsackie, echovirus), mumps, herpesviruses, measles Bacterial causes are less common but more serious In adults, the most common bacteria is N. meningitidis and S. pneumoniae In babies, group B streptococci and E. coli are common causes Symptoms Early

Orbital Cellulitis This is an infection of the structures which lie behind the orbital septum. It is usually seen in young children. It is more severe than pre-septal cellulitis and will have worse symptoms (e.g., proptosis, ophthalmoplegia). Patients usually have a history of an URTI (e.g., sinusitis) or pre-septal cellulitis.   Symptoms Redness and swelling around eye with pain Painful eye movements Proptosis (bulging of the eye) In preseptal cellulitis, you do not get reduced visual acuity or painful eye movements Key tests Bloods show raised inflammatory markers Blood cultures to assess for bacteremia CT with contrast of the orbit

Parkinson’s disease This is a disease where the dopaminergic neurons in the substantia nigra are progressively lost, resulting in the development of symptoms. Parkinsonism can be drug-induced (gives rapid-onset bilateral motor symptoms)   Symptoms Tremor, described as a pill-rolling motion of thumb over fingers, which is usually worse at rest and typically improves with movement Bradykinesia – slow initiation of voluntary movements Hypertonia – increased muscle tone, which gives cogwheel rigidity in the extremities Postural instability and shuffling/festinant gait (pitched forward gait) Expressionless face (“mask-like”) Psychiatric – depression (most common symptom), dementia and psychosis Micrographia, anosmia Autonomic dysfunction (postural hypotension and

Meningitis This is inflammation of the leptomeninges (pia and arachnoid mater) lining the brain. It is most commonly due to an infectious agent, which can lead to an increase in intracerebral pressure and the development of cerebral oedema. If left untreated, it can lead to hydrocephalus, hearing loss, fibrosis and death by cerebral herniation.   Causes Viruses (most common cause), e.g., enterovirus (coxsackie, echovirus), mumps, herpesviruses, measles Bacterial causes are less common but more serious In adults, the most common bacteria is N. meningitidis and S. pneumoniae In babies, group B streptococci and E. coli are common causes Symptoms Early

The commonest aetiologies of dementia are: Alzheimer’s disease, Vascular and Lewy body dementia. – These conditions are difficult to diagnose and there are many assessment tools e.g. GPCOG, abbreviated mental test score (AMTS) and the mini-mental state examination (MMSE)   Investigation pathway: – 1st do a cognitive assessment e.g. MOCA – Exclude reversible causes – do FBC, U&E, LFTs, calcium, glucose, TFT, Vit B12 and folate (2) – Imaging – CT head (structural causes) and MRI (vasculature changes)    Alzheimer’s disease The number one cause of dementia in the UK is Alzheimer’s disease. The disease is characterised by a progression degeneration

Tumours of the brain can be primary or metastases from other origins. Metastases usually present as numerous, well demarcated lesions. They are typically seen at the grey-white matter junction and originate from lung, breast, kidney cancer and malignant melanomas.   The classification of primary tumours can be divided according to type of cell: e.g., astrocytes, oligodendrocytes. In adults, the most common primary tumours are glioblastoma multiforme, meningiomas and schwannomas. In children, the most common primary tumour is a pilocytic astrocytoma. Symptoms Initially painless as the brain lacks nociceptors (meninges have nociceptors) Pressure symptoms – headaches (worse on waking, bending over),

Bell’s Palsy This is an idiopathic facial nerve palsy which causes lower motor neurone symptoms. It is an acquired condition which is more prevalent in pregnant women and is more commonly seen below the age of 40. Whilst idiopathic, it is often thought to be an inflammatory reaction following a viral infection and is also associated with diabetes mellitus.   Symptoms Acute onset unilateral weakness of the whole face, including eyebrows, (stroke spares the forehead due to bilateral UMN innervation of the facial nerve nucleus) Ipsilateral numbness and pain around the ear Decreased taste, due to damage to the chorda

The eye is supplied by the optic nerve (cranial nerve II) and it is divided in anterior and posterior chambers:– Anterior chamber is the space that lies between the cornea and iris– Posterior chamber is the space from the iris back to the lens.  Cornea This is the clear bulging surface in front of the eye which is the main refractive surface of the eye.– It gets nutrition from the aqueous humor and from tears.   Iris This contains the sphincter muscle to constrict and dilate pupil– Parasympathetic stimulation constricts whereas sympathetic dilates   Lens This is a transparent body

The PNS is divided into the somatic nervous system and the autonomic nervous system, which operates subconsciously, out of our control: Somatic systemThis controls skeletal muscle– Motor neurons release ACh which acts at nicotinic ACh receptors Parasympathetic:– Preganglionic release ACh on nicotinic receptors–  Postganglionic release ACh on muscarinic receptors Sympathetic:– Preganglionic release ACh on nicotinic receptors– Postganglionic release NA on adrenergic receptors.   ACh acts at the synaptic cleft and is broken down by phosphodiesterase enzymes into Acetyl CoA + choline– NA is broken down by monoamine oxidase (MAO) and COMT into Vanylmandelic acid    Sensory System This is composed

12 cranial nerves supply the head and the neck, which have a variety of sensory and motor function I – Olfactory Foramen:Cribriform plate Modality:Special Sensory Function:Smell   II – Optic Foramen:Optic canal Modality:Special Sensory Function:Vision   III – Occulomotor Foramen:Superior Orbital Fissure Modality:Special Sensory Function:Innervation to eye muscles –> Levator palpebrae superioris, superior, Medical & Inferior ObliqueParasympathetic to ciliary muscles and sphincter pupillae   IV – Trochlear Foramen:Superior Orbital Fissure Modality:Somatomotor Function:Innervation to superior oblique   V – Trigeminal Foramen:Superior Orbital Fissure (Va)Foramen Rotundum (Vb)Foramen Ovale (Vc) Modality:Somatosensory and branchiomotor Function:Sensation –> Head and neck, paranasal sinuses, meninges, and external

Disorders of the labyrinth   Benign Paroxysmal Positional Vertigo This is a condition which causes movement-dependent vertigo. It is seen more in elderly patients. Symptoms come on suddenly when head position is altered. It is not difficult to treat, but the symptoms do tend to recur after a few years.   Symptoms Vertigo worsened by head movement, e.g., turning in bed Each episode lasts less than 30 seconds and can make the patient feel sick/extremely dizzy Key tests A positive Dix-Hallpike manoeuvre – this reproduces vertigo and nystagmus is seen in the affected side   Management Recovery is normally spontaneous

Orbital Cellulitis This is an infection of the structures which lie behind the orbital septum. It is usually seen in young children. It is more severe than pre-septal cellulitis and will have worse symptoms (e.g., proptosis, ophthalmoplegia). Patients usually have a history of an URTI (e.g., sinusitis) or pre-septal cellulitis.   Symptoms Redness and swelling around eye with pain Painful eye movements Proptosis (bulging of the eye) In preseptal cellulitis, you do not get reduced visual acuity or painful eye movements Key tests Bloods show raised inflammatory markers Blood cultures to assess for bacteremia CT with contrast of the orbit

Tumours of the brain can be primary or metastases from other origins. Metastases usually present as numerous, well demarcated lesions. They are typically seen at the grey-white matter junction and originate from lung, breast, kidney cancer and malignant melanomas.   The classification of primary tumours can be divided according to type of cell: e.g., astrocytes, oligodendrocytes. In adults, the most common primary tumours are glioblastoma multiforme, meningiomas and schwannomas. In children, the most common primary tumour is a pilocytic astrocytoma. Symptoms Initially painless as the brain lacks nociceptors (meninges have nociceptors) Pressure symptoms – headaches (worse on waking, bending over),

Migraine This is a primary headache which is more common in women and can be debilitating. In a migraine, there is an increase in cerebral activity, which releases 5-HT. This activates the endothelium by binding 5-HT2 receptors causing vasodilation and sensitising nerve endings. 5-HT1D/1B activation inhibits this vasodilation and inflammation of meninges. A hallmark is that approximately a third are precipitated by an aura, a reversible sensory or motor phenomenon which develops over 5 minutes and lasts < 1 hour. These auras include changes of taste/smell, scintillating scotoma/flashing lights, dysphasia. Triggers Alcohol Menstruation Bright lights Stress Contraceptive pill Certain foods (cheese, chocolate,

Syringomyelia This is a cyst or cavity that forms within the spinal cord. Due to the organisation of the sensory pathways, it affects the decussating fibres of the spinothalamic system affecting pain and temperature sensation, and it does not affect the dorsal column neurones.   Causes Acquired – post meningitis/arachnoiditis, spinal cord tumour or injury Congenital – associated with the Chiari malformation (lower cerebellum protrudes through the foramen magnum into the cervical canal) which blocks the flow of CSF   Symptoms Cape-like” distribution of absent pain and temperature Spared sense of touch, vibration and proprioception If it is associated with

This term describes a tendency to have seizures: these are episodes of sudden and abnormal electrical activity in the brain. Convulsions are motor signs of the electrical discharges.   Seizures are often preceded by a prodrome – this may last for hours and are characterised by a change in mood/behaviour or a nonspecific “funny feeling.” Seizures are usually stereotypical, i.e., same aura and ictal features An aura occurs just prior to the seizure and may include a feeling of d.j. vu, sensory hallucinations, emotional feelings, limb sensations or visual disturbances. Post-ictally, patients can experience headache, fatigue, confusion, myalgia and weakness

Myasthenia Gravis This is an autoimmune disease caused by autoantibodies against nicotinic acetylcholine receptors (AchR) at the neuromuscular junction (NMJ). There can be additional antibodies against muscle-specific kinase (MuSK) protein. It is more common in women and associated with thymus hyperplasia and thymoma.   Symptoms Use dependent muscle weakness – this worsens with activity and improves with rest Weakness typically starts with eyes (ptosis, diplopia), and can spread (or generalise) to face, bulbar muscles, neck, trunk, and limbs (proximal > distal muscle weakness) Symptoms are exacerbated by infections, surgery, and some drugs, e.g., beta-blockers, lithium, certain antibiotics (ciprofloxacin, gentamicin)  

Meningitis This is inflammation of the leptomeninges (pia and arachnoid mater) lining the brain. It is most commonly due to an infectious agent, which can lead to an increase in intracerebral pressure and the development of cerebral oedema. If left untreated, it can lead to hydrocephalus, hearing loss, fibrosis and death by cerebral herniation.   Causes Viruses (most common cause), e.g., enterovirus (coxsackie, echovirus), mumps, herpesviruses, measles Bacterial causes are less common but more serious In adults, the most common bacteria is N. meningitidis and S. pneumoniae In babies, group B streptococci and E. coli are common causes Symptoms Early

Bell’s Palsy This is an idiopathic facial nerve palsy which causes lower motor neurone symptoms. It is an acquired condition which is more prevalent in pregnant women and is more commonly seen below the age of 40. Whilst idiopathic, it is often thought to be an inflammatory reaction following a viral infection and is also associated with diabetes mellitus.   Symptoms Acute onset unilateral weakness of the whole face, including eyebrows, (stroke spares the forehead due to bilateral UMN innervation of the facial nerve nucleus) Ipsilateral numbness and pain around the ear Decreased taste, due to damage to the chorda

Parkinson’s disease This is a disease where the dopaminergic neurons in the substantia nigra are progressively lost, resulting in the development of symptoms. Parkinsonism can be drug-induced (gives rapid-onset bilateral motor symptoms)   Symptoms Tremor, described as a pill-rolling motion of thumb over fingers, which is usually worse at rest and typically improves with movement Bradykinesia – slow initiation of voluntary movements Hypertonia – increased muscle tone, which gives cogwheel rigidity in the extremities Postural instability and shuffling/festinant gait (pitched forward gait) Expressionless face (“mask-like”) Psychiatric – depression (most common symptom), dementia and psychosis Micrographia, anosmia Autonomic dysfunction (postural hypotension and

Ischaemic Stroke This refers to brain ischaemia that results in neurological damage lasting > 24 hours. It occurs due to occlusion of an artery which reduces blood flow to the brain.   Embolic This is where a clot breaks off and occludes a part of the cerebral circulation. The most frequent source of emboli are clots dislodged from the left side of the heart, in patients with atrial fibrillation. These often block the middle cerebral artery (MCA). Emboli can cause single arterial blockage or ‘showers’ to multiple arteries and arterial distributions.   Thrombotic This is a stroke due to a rupture of

Extradural Haematoma An extradural haematoma is a bleed into the “potential” space between the dura mater meningeal layer and the inner surface of the skull. It usually occurs due to low impact trauma to the side of the head, resulting in laceration of the middle meningeal artery running deep to the pterion. This causes the dura to peel away from the inner layer of the skull. As the bleed enlarges it compresses the brain and raises intracranial pressure causing symptoms. Symptoms Initial headache and loss of consciousness Causes a lucid interval (hours to days) as the haematoma grows This is