Neurology

1. Neurology Adam Couves 0606330c@student.gla.ac.uk

2. Today we will cover… The two big ‘uns: • Stroke • Parkinson’s Disease

3. Aims Past paper questions: • Definitions • Aetiology • Clinical pictures • Differential diagnoses • Management • Complications

4. Stroke • Acute neurological deficit (usually focal) of cerebrovascular origin lasting >24 hours • <24 hours = TIA • Two types: • Ischaemic • Haemorrhagic

5. Pathophysiology • Usually thrombotic embolus • Origins: • Heart (AF, MI) • Carotids (atherosclerosis) • Lodges distally occluding blood supply and hence ↓O2 delivery to cerebral tissue

6. Ischaemic Cascade • Failure of ATP dependant Na+/K+ pump – depolarisation • Glutamate toxicity • Ca2+ influx into cells • Initiating wide spread destructive effects • Progressive infarction

7. Risk Factors • Cardiac: • MI • AF • Valvular heart disease • Cheeky extra: • Previous Stroke / TIA • Atherosclerosis: • Smoking • Diabetes • Hypercholesterolaemia • Age • SE Asian heritage • Thrombosis: • Oral Contraceptive Pill • Polycythaemia • Thrombophilia • Vasculitis

8. Clinical Picture • Related to neuroanatomy:

9. Total Anterior Circulation Syndrome • Usually proximal MCA or ICA occlusion • Hemiparesis • Higher Cortical Dysfunction • Dysphasia • Visuospatial neglect • Homonymous Hemianopia

10. Homonymous Hemianopia • Optic radiation runs along MCA territory

11. Partial Anterior Circulation Syndrome • Usually branch MCA occlusion • Any 2 out of 3: • Hemiparesis • Higher Cortical Dysfunction • Dysphasia • Visuospatial neglect • Homonymous Hemianopia

12. POsterior Circulation Syndrome • Vertebral, Basilar, Cerebellar or PCA vessels • Isolated Hemianopia (PCA) • Brainstem Syndromes • Cerebellar Syndromes

13. LACunar Syndrome • Basal Ganglia - supplied by end arteries (lenticulostriate arteries) • Pure Motor Stroke → Internal Capsule • Pure Sensory Stroke → Thalamus • Sensorimotor Stroke • Ataxic Hemiparesis • Clumsy Hand Dysarthria

14. Differential Diagnosis • Todd’s Paresis (post – ictal) • Bell’s Palsy / VII CN HSV infection • Cerebral Tumour • Brain Abscess • Hypoglycaemia • Encephalitis • Subdural Haematoma • Traumatic Brain Injury

15. ACUTE MANAGEMENT • Airway • Protected • Swallowing? • Breathing • Adequate on air? • Circulation • Fluid replacement if BP ↓ • Do not routinely treat hypertension • Disablility • GCS • Pupils • Exposure • Sustained other injuries with fall? • Concomitant pathologies? • GLUCOSE!

16. Investigations: • CT Scan: • Rule out HAEMORRHAGE • Exclude tumour • Evidence of early ischaemic changes • Bloods – FBC, U+E, Glucose, Coagulation, ESR • Cardiac • ECG • Echo • Carotid doppler US • CXR – heart size, lung pathology, tumours

17. Thrombolysis • Administered <4.5hrs of symptom onset • Recombinant tissue Plasminogen Activator (rtPA) = “alteplase” • Binds to fibrin and activates plasminogen → cleaves fibrin → degrades thrombus • Also give Aspirin 300mg

18. Contraindications • Extremes of age (>80 or <18) • NIHSS > 25 or NIHSS <4 • Previous severe disability / terminal illness • Hx ICH / neoplasm or AV malformation • Stroke / prev head trauma (3/12) • Platelets ↓or INR > 1.5 • Pregnancy / Recent Childbirth (2 weeks) • Recent MI (1 month) • Active Bleeding / Acute Trauma • Major Surgery (2 weeks)

19. Complications • Dysphagia • Malnutrition / Medications • Aspiration pneumonia • Immobility • Muscle wasting and contractures • Pressure sores → ulceration → infection • Falls • Osteoporosis • Incontinence • Skin integrity • Retention of Urine • Catheterisation → UTI • Epilepsy • Depression • Death

20. Secondary Prevention • Antiplatelet • Aspirin 300mg (2/52) then 75mg • Dipyridamole 200mg • Statin • BP (aggressive if DM) • Carotid Endarterectomy • Lifestyle

21. Parkinson’s Disease

22. Parkinsonism Triad of Symptoms: • Tremor • Unilateral • 4-6 Hz • Pin - rolling • Worse at rest • Rigidity • Lead pipe • Cog-wheeling • Bradykinesia • Serpentine Stare (Hypomimia) • Reduced arm swing • Reduced frequency and amplitude of repetitive movements • Worse with co-stimulation • Loss of Postural reflexes • Pull test • Difficulty turning around • Early falls

23. Idiopathic Parkinson’s Disease • Progressive degeneration of dopaminergic neurons of nigrostriatal pathway (Subtantia Nigra → Lentiform Nucleus) • Disrupting complex feedback mechanisms involved in initiating and maintaining movement • Symptoms arise when 60-80% of neurons are lost

24. Non-motor Symptoms • Sensory • Anosmia!! • Psychological • Depression • Obsessive and Impulsive behaviours • Dementia • Hallucinations • Sleep Disorders • Urinary Incontinence • Dysphagia and Gastro-Oesophageal reflux • Sweating and pale cool skin • Erectile dysfunction

25. Management • Levodopa • Combined with Carbidopa (Sinemet) • Improve pharmaco-kinetic profile • Reduce side effects • Postural hypotension • Nausea • Hallucinations L-DOPA L-DOPA DOPA Dopamine

26. Dopamine Agonists • E.g. Ropinirole, Apomorphine Agonise dopamine receptors

27. MAOI – Selegine DOPA Dopamine 3-MT MAOI HVA 3-4-DPA

28. COMT-I - Entacapone 3-OMD DOPA Dopamine 3-MT COMT-I

29. Considerations for L-DOPA? • Age of patient • Disease severity • Dysphagia / Gut motility • Preparation • Protein • Side effects On / Off syndrome

30. Differentials - Parkinsonism

31. Akinetic Rigid Syndromes