Stroke Mimics. Paul Guyler

Transcription

1 Stroke Mimics Paul Guyler Consultant Stroke Physician at Southend University Hospital Clinical Lead for Acute Stroke Essex Cardiac and Stroke Network

2 Aims Why worry? Stroke Recognition Tools History, Examination and imaging Defining an approach to acute neurological symptoms FAST +ve Mimics FAST ve Strokes FAST ve Mimics Non-acute stroke presentations

3 Distinguishing stroke from mimics Diagnostic inaccuracy approx 25% Similar error rate for trained paramedics, A+E and GPs 1 Risk of patient being inappropriately thrombolysed Risk of patient not being given correct treatment promptly 2 1 Azzimondi et al Stroke Harbison et al Stroke 2003

4 Pathway activation by A+E TPA 17% Age 8% >3hrs 4% Other Exclusion 4% No Time Line 10% Too Mild/TIA 15% Non Stroke 23% Too severe 4% ICH/SAH 15% 101 cases assessed in A+E, Leeds General Infirmary 1/7/ /10/2008

5 Causes of Stroke Mimics (n=109) Condition % <6hrs >6hrs Seizure Sepsis Toxic/metabolic SOL Syncope Delirium Vestibular Mononeuropathy Functional Dementia Migraine Hand et al Stroke 2006

6 Causes of Stroke Mimics (n=109) Condition % <6hrs >6hrs Seizure Sepsis Toxic/metabolic SOL Syncope Delirium Vestibular Mononeuropathy Functional Dementia Migraine

7 Used widely by paramedics Public educational campaigns Any 1 of 3 symptoms Rapid. Quick screening tool Sensitivity/Specificity 80% Positive predictive value 90%

8 Rosier scale Used in Emergency room 7 point scoring system Higher sensitivity 93% Specificity= 83% Positive predictive value 90% Nor et al, Lancet Neurol 2005

9 Tools make things easier but not infallible. Prospective testing.. False + Functional Hemiplegic/complex migraine False -ve Mild CVAs (LACS) POCS

10 FAST -ve FAST +ve Tools make things easier but not infallible. Strokes Non-strokes The classic mimic FALSE POSITIVES FAST ve strokes FALSE NEGATIVES

11 Logistic regression model for predicting diagnosis of brain attack OR 95%CI Known cognitive impairment Exact onset determined 2.59 ( ) Definite focal symptoms 7.21 ( ) Abnormal vascular findings 2.54 ( ) NIHSS ( ) ( ) > ( ) Signs localise to either left or right 2.03 ( ) OCSP classification possible 5.09 ( )

12 Hyperacute radiology for stroke mimic Non contrast CT widely available Limited role, often normal Early infarct signs confirm clinical suspicion of stroke Rarely non stroke neurological mimics seen e.g. SOL Rarely clarifies clinical picture, if diagnostic confusion from outset (advanced imaging more useful)

13 FAST -ve FAST +ve Approach to acute neurological symptoms Strokes Non-strokes The classic stroke The classic mimic FAST ve strokes Mimics of FAST -ve strokes

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16 FAST -ve FAST +ve Approach to acute neurological symptoms Strokes Non-strokes The classic stroke The classic mimic FAST ve strokes Mimics of FAST -ve strokes

17 FAST +ve mimics Hypoglycemia Migraine with/without aura / Hemiplegic Migraine Post-ictal paralysis Brain Tumours Intracerebral haemorrhage Subarachnoid hemorrhage Subdural haemorrhage Cervical spondylotic myelopathy Venous infarction Hypertensive encephalopathy Functional hemiparesis Others!

18 Hypoglycemia (Fast +ve mimic) Adrenergic symptoms/signs can be absent Neuroglycopenia Hemiplegia Quadreplegic brainstem signs Signs usually reverse after glucose Could lead to permanent neurological sequelae Ravid JM: Transient insulin hypoglycemic hemiplegias. Am J Med Sci 1928;175:

19 ROSIER SCALE

20 Migraine with/without aura increase in stroke risk Strokes can mimic migraine! Neurological disturbance is almost always transient.

21 Differentiating stroke/tia from migraine Focal symptoms precede headache & are usually +ve Note headache seen in up to 50% of TIAs; seen at onset, usually ipsilateral & non-severe 1 Usually visual fortification spectra, hemianopia, perioral tingling & tingling in 1 arm, occ. dysphasia Often march over ~15 mins. 1. Chaturvedi et al. Transient ischaemic attacks. Blackwell, 2004

22 Hemiplegic Migraine (FAST+ve mimic) Watch for the typical march of symptoms Usual duration of neurological symptoms is 30 minutes to up to 2 hours Headaches could be ipsilateral or contralateral In this familial variety, neurological signs could become permanent Frank hemiplegias ataxia and other cerebellar signs coma

23 Post-ictal paralysis (Fast +ve mimic) Lasts under 24 hours; rarely longer The residual neurology strongly points to the origin of the epileptic focus In up to 15% of the epileptic attacks Mono or hemiplegia aphasia gaze deviation hemianopia

24 Brain Tumours (FAST +ve mimic) Tumours can cause transient neurological symptoms lasting minutes or indeed permanent There are symptoms which are acute by nature eg Dysphasia, diplopia, dysphagia Remember, without a contrast CT scan, metastasis and tumours can appear like infarcts Remember symptoms relating to the tumour oedema can resolve well with steroids (temporarily).

25 67 M NE CT NE CT CE CT CE CT

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27 55 F NE CT CE MRI

28 48 F Intracerebral haemorrhage Acute ischaemic stroke can only be differentiated from an acute haemorrhagic stroke by brain imaging (CT or MRI)

29 Subarachnoid haemorrhage Sudden onset 10/10 headache Variable neurology History crucial Positive history even with negative CT C/I for rtpa 5% have normal CT

30 48 F Acute Headache,disoriented

31 Subdural haemorrhage (FAST +ve mimic) SDH s can present with transient or permanent FAST +ve neurological deficits Up to a third of the chronic subdural haematomas could be a fast +ve mimic

32 73 YRS

33 Cervical spondylotic myelopathy Different mechanisms Silent/chronic Acute Coexist

34 Case illustration Had a fall, weak right side with N. signs CT normal Had unexplained upgoing left plantar History explored MR C spine

35 VENOUS INFARCTION Think about it! On CT be suspicious if see bilateral low densities or low density in non-arterial distribution. NB temporal lobe. Look for high attenuation thrombus on non contrast CT scan Can confirm with enhanced scan or preferably CTV

36 Low density left temporal lobe; dense transverse sinus

37 Post contrast CT showing normal right and occluded/thrombosed left sigmoid and transverse sinus

38 Hypertensive encephalopathy (FAST +ve mimic) Neurological deficits Hemiplegia Usually occurs in longstanding HT Bilateral clumsiness Drowsiness Imaging may show abnormalities which disappear after treatment Coma Bilateral upgoing plantars Cautious BP control overzealous treatment or undertreatment can cause strokes!

39 Functional hemiparesis (Fast +ve mimic) Common! Never underestimate the importance of this Could be an overlay on some pathology Fool proof imaging +/_ 2 nd opinion Antidepressants are of value whether or not a patient is depressed

40 Other potential fast +ve mimics Multiple sclerosis Encephalitis Peripheral nerve palsies Musculoskeletal injuries Intracerebral abcess Early Idiopathic Parkinsonism 41 M - Aids

41 FAST -ve FAST +ve Approach to acute neurological symptoms Strokes Non-strokes The classic stroke The classic mimic FAST ve strokes Mimics of FAST -ve strokes

42 Cerebellar strokes Fast ve strokes Occipital infarcts Non-dominant parietal lesions Sensory strokes Frontal infarcts causing just leg weakness

43 Dense basilar artery due to thrombosis

44 FAST -ve FAST +ve Approach to acute neurological symptoms Strokes Non-strokes The classic stroke The classic mimic FAST ve strokes Mimics of FAST -ve strokes

45 Mimics for FAST-ve strokes Vestibular neuronitis Falls (ataxia) Transient Global amnesia

46 Transient global amnesia Sudden onset, loss of registration of events during the attack and associated loss of retrograde memory. Repetitive questioning a hallmark Patients appear confused but personal identity and intellect preserved

47 Non-acute stroke presentations Stuttering/progressive symptoms

48 Non-acute stroke presentations Patient who has a stroke and refuses or unable to accept it! Wrong diagnosis due to pitfalls in investigations

49 SUMMARY Try and have a logical approach to acute neurological symptoms FAST +ve vs FAST ve Good luck!!