How To Diagnose And Diagnose Stroke

Transcription

1 Stroke diagnosis and misdiagnosis Dr. Peter Enevoldson Consultant Neurologist Walton Centre for Neurology & Neurosurgery Liverpool

2 Stroke A clinical syndrome characterised by rapidly developing clinical symptoms and/or signs of focal, and at times global, loss of cerebral function, with symptoms lasting more that 24 hours or leading to death, with no apparent cause other than that of vascular origin. Not: SAH

3 WHY DO DIAGNOSTIC PROBLEMS OCCUR? 1. History 2. Examination 3. Investigation 4. Subsequent events

4 PROBLEMS IN THE HISTORY. a) Timing: abrupt/acute, but some stuttering and/or more prolonged onset b) Non-focal or poorly localising symptoms, e.g behavioural c) Patient problems: Dysphasic No witnesses Impaired conscious level Confusion d) Doctor problems: e) Inadequate description: Nature of deficit(s) Time course Accompanying focal features How noticed/what doing Misinterpretation of previous events, TIAs f) Assuming and ignoring the obvious. Age & PMH

5 PROBLEMS IN THE EXAMINATION 1. Over-reliance on weakness, especially in the limbs 2. Failure to appreciate non-organic signs How history delivered Physical examination 3. Dysphasia = confusion 4. Spectrum of normal to abnormal

6 PROBLEMS WITH INVESTIGATIONS (radiology may let you down!) 1. Main test (CT brain) may be normal or abnormal 2. Coincidental abnormalities, misleading either way. Age-related Congenital

7 PROBLEMS WITH INVESTIGATIONS 1. Main test (CT brain) may be normal or abnormal 2. Coincidental age-related or congenital abnormalities, misleading either way. 3. Timing 4. Beware posterior fossa in CT. 5. Misinterpretation of abnormalities 6. Over-reliance on reports

8 Each can let you down diagnostically History Examination Tests Must consider them all together

9 SUBSEQUENT EVENTS Continued progression Failure to review history and examination, and to re-investigate if not behaving typically

10 NON-VASCULAR CAUSES OF STROKE Seizures + Todd s Structural lesions Tumour Subdural haematoma Infections Early encephalitis Brain abscess Subdural empyema PML (CJD) Multiple Sclerosis Psychological

11 NON-VASCULAR CAUSES OF STROKE Neuromuscular Peripheral nerve lesions, especially ulnar, radial, posterior interosseous Root lesions, esp C7 MND Myasthenia Metabolic Hypoglycaemia Hyperglycaemia Hyponatraemia Labyrinthine Disturbances Labyrinthitis Meniere s Miscellaneous Head Injury Hypertensive encephalopathy Reversible posterior leukoencephalopathy syndrome Wernicke s encephalopathy

12 Examples

13 RED FLAGS 1. Young and/or no vascular risk factors 2. History unclear 3. Atypical clinical features gradual or situationally noticed onset seizures confusion or impaired consciousness out-with other signs 4. Progressive worsening 5. Seen very early or very late 6. Brainstem and/or cerebellar features 7. History of Other neurological disease Cancer Renal or hepatic disease Alcoholism Immuno-suppression (disease or drugs) Unexplained medical symptoms During pregnancy/post-partum

14 FUNCTIONAL/SOMATIZATION DISORDER Usually young Usually lack vascular risk factors (but beware angina ) Often multiple unexplained symptoms or syndromes over many years or operations Often other diagnoses such as:. sero-negative SLE. sero-negative arthritis. fibromyalgia. cholecystectomy, appendicectomy and hysterectomy May or may not have any psychiatric history apparent

15 FUNCTIONAL/SOMATIZATION DISORDER HISTORY History usually. vague, list. inconsistent within one telling. inconsistent between tellings. contains mutually inconsistent features Presentation often delayed e.g. 3/7 after onset of severe hemiparesis Features change with repeated telling

16 FUNCTIONAL/SOMATIZATION DISORDER EXAMINATION Variable from one examination to another. No objective features e.g. tone, reflexes, plantars Variable effort & power grunts/grimaces agonist/antagonist encourage up to normal ( one finger test ) collapsing quality to the weakness Mutual inconsistencies e.g. numb hand/tie laces make-up/jewellery/buttons high-heels Non-sensical sensory signs turn over no vibration on sternum finger to nose

17 NON-VASCULAR CAUSES OF STROKE Seizures + Todd s Psychological Multiple Sclerosis Migraine Structural lesions Tumour Subdural haematoma Infections Early encephalitis Brain abscess Subdural empyema (PML) (CJD) Neuromuscular Peripheral nerve lesions, especially ulnar, radial, posterior interosseous Root lesions, esp C7 MND Myasthenia Metabolic Hypoglycaemia Hyperglycaemia Hyponatraemia Hepatic encephalopathy Labyrinthine Disturbances Labyrinthitis Meniere s Miscellaneous Head Injury Hypertensive encephalopathy Reversible posterior leukoencephalopathy syndrome Wernicke s encephalopathy