Transient ischemic attack (TIA) is defined as a transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction. Ischemic stroke is defined as an infarction of central nervous system tissue. The symptoms of TIAs are typically focal and depend upon the underlying vascular cause ( table 1). (See 'Transient ischemic attack' above.) In addition to TIA, the most important and frequent causes of discrete self-limited attacks include seizure, migraine aura, and syncope ( table 2). Transient global amnesia or TGA is an uncommon syndrome characterized by the acute onset of temporary but severe anterograde amnesia accompanied by retrograde amnesia, without other cognitive or focal neurologic impairment. (See 'Transient neurologic events' above.) Other less frequent causes of transient neurologic events include hypoglycemia, multiple sclerosis, brain tumor, subdural hematoma, cerebral amyloid angiopathy, various toxic or metabolic encephalopathies, compressive myelopathy, nerve root compression, peripheral vestibulopathies, and psychogenic etiologies. (See 'Other causes' above.) Useful features for distinguishing the various causes of transient attacks include the focal or nonfocal nature of attacks, the nature of the symptoms and their progression, the duration and timing of symptoms, and associated symptoms during and after the attacks ( table 2). Some disorders cause focal abnormalities of brain function, while others cause dysfunction that is either widespread or difficult to localize to any one anatomic region ( table 3). Certain disorders may cause both focal and nonfocal attacks. (See 'Distinguishing transient attacks' above.) The evaluation of a patient presenting with acute symptoms suggestive of TIA or ischemic stroke is outlined in the algorithm ( algorithm 1) and discussed in detail separately. (See "Initial evaluation and management of transient ischemic attack and minor ischemic stroke".) https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 13/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate Use of UpToDate is subject to the Terms of Use. REFERENCES 1. Caplan LR. TIAs: we need to return to the question, 'What is wrong with Mr. Jones?'. Neurology 1988; 38:791. 2. Caplan LR. Transient ischemic attack: definition and natural history. Curr Atheroscler Rep 2006; 8:276. 3. FISHER M. Occlusion of the internal carotid artery. AMA Arch Neurol Psychiatry 1951; 65:346. 4. Albers GW, Caplan LR, Easton JD, et al. Transient ischemic attack proposal for a new definition. N Engl J Med 2002; 347:1713. 5. Caplan LR. Transient ischemic attack with abnormal diffusion-weighted imaging results: what's in a name? Arch Neurol 2007; 64:1080. 6. Kumar S, Caplan LR. Clinical syndromes - brain. In: Transient ischemic attacks, 1st ed, Chatur vedi S, Levine SR (Eds), Blackwell Publishing, Malden 2004. p.73. 7. MONTGOMERY BM, PINNER CA. TRANSIENT HYPOGLYCEMIC HEMIPLEGIA. Arch Intern Med 1964; 114:680. 8. Bos MJ, van Rijn MJ, Witteman JC, et al. Incidence and prognosis of transient neurological attacks. JAMA 2007; 298:2877. 9. van Rooij FG, Vermeer SE, G raj BM, et al. Diffusion-weighted imaging in transient neurological attacks. Ann Neurol 2015; 78:1005. 10. Kumar S, Selim M, Marchina S, Caplan LR. Transient Neurological Symptoms in Patients With Intracerebral Hemorrhage. JAMA Neurol 2016; 73:316. 11. Cochrane T, Schmahmann JD. Compressive myelopathy presenting as cervical cord neurapraxia: a differential diagnosis of TIA. Neurology 2005; 65:1140. 12. Muraszko KM, Oldfield EH. Vascular malformations of the spinal cord and dura. Neurosurg Clin N Am 1990; 1:631. 13. Krings T, Geibprasert S. Spinal dural arteriovenous fistulas. AJNR Am J Neuroradiol 2009; 30:639. 14. Villani F, D'Amico D, Pincherle A, et al. Prolonged focal negative motor seizures: a video-EEG study. Epilepsia 2006; 47:1949. 15. Fisher CM. Transient paralytic attacks of obscure nature: the question of non-convulsive seizure paralysis. Can J Neurol Sci 1978; 5:267. https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 14/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate 16. Fisher CM. Migraine accompaniments versus arteriosclerotic ischemia. Trans Am Neurol Assoc 1968; 93:211. 17. Caplan LR. Nonatherosclerotic vasculopathies. In: Caplan's Stroke: A Clinical Approach, 4th e d, Saunders, Philadelphia 2009. p.389. 18. Liberman A, Karussis D, Ben-Hur T, et al. Natural course and pathogenesis of transient focal neurologic symptoms during pregnancy. Arch Neurol 2008; 65:218. Topic 1137 Version 19.0 https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 15/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate GRAPHICS Symptoms of transient ischemic attacks and the vascular territories involved ICA/MCA VA/BA PCA SVD Visual abnormalities Transient ++++ monocular blindness Hemianopia + +++ Blindness ++ ++ Motor abnormalities Hemiparesis + + ++ Quadriparesis ++++ Single part weakness Face + ++ + Arm/hand +++ + Thigh/leg/foot ++ + + Crossed weakness* ++++ Limb ataxia/weakness ++ ++ Gait ataxia +++ + Sensory abnormalities Hemisensory + ++ ++ Single part sensory Face + ++ + ++ Arm/hand ++ ++ + Thigh/leg/foot + + + + Crossed sensory* ++++ Cognitive abnormalities Aphasia ++++ + https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 16/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate Amnesia + +++ Alexia +++ +++ Abulia ++ + + Brainstem and cranial nerve symptoms Dizziness/vertigo + +++ Diplopia ++++ Dysarthria + ++ ++ Dysphagia ++ ++ Tinnitus/hearing loss ++++ ICA: internal carotid arteries; MCA: middle cerebral arteries; VA: vertebral arteries; BA: basilar artery; PCA: posterior cerebral arteries; SVD: small vessel disease. Crossed weakness or crossed sensory refers to one side of the cranial structures and the opposite side limbs and trunk. Graphic 71676 Version 5.0 https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 17/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate Clinical features of seizures, syncope, and other paroxysmal neurologic events in adults Clinical Recall of the Diagnostic Duration features event tools Focal seizure Initial symptoms depend on location in brain; Usually <2 minutes; can be difficult to Variable depending on whether EEG may show interictal spikes (poor sensitivity); motor and visual symptoms usually "positive" (eg, shaking, jerking, flashing lights, or visual distortion); distinguish ictal from postictal phase consciousness is impaired ambulatory EEG if episodes are frequent enough; MRI may show structural lesion may have anatomic "march" over seconds; some progress rapidly to GTC Generalized seizure Sudden alteration or loss of <5 minutes (for GTC); <1 minute Complete amnesia; patient EEG may show generalized spike- consciousness without warning; some have myoclonic jerks or staring; tongue- biting and urinary incontinence may for absence may recall initial focal symptoms and-wave characteristic of specific syndrome; MRI usually normal for generalized epilepsy occur (for GTC) syndromes, may show structural lesion if focal onset Psychogenic nonepileptic seizure Fluctuating, asynchronous motor activity, Rarely <1 minute; often prolonged (>30 minutes) Variable Video-EEG monitoring often with eye closure, side-to- side head or body movements, pelvic thrusting; most occur in front of a witness; fully or partially https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 18/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate alert despite bilateral motor activity; tongue- biting is rare Syncope Transient loss of 1 to 2 minutes Patient can recall ECG; consciousness resulting in loss of postural tone; prodrome of lightheadedness, warm or cold prodromal symptoms, if present; lack of warning may suggest cardiac source echocardiography if structural cardiac disease is suspected; ambulatory ECG monitoring if feeing, sweating, palpitations, pallor; myoclonic jerks or tonic posturing may occur, especially if arrhythmia is suspected; orthostatic blood pressure measurements patient is kept upright; no or minimal post- event confusion Transient ischemic attack (TIA) Rapid loss of neurologic function due to interrupted blood flow; symptoms Several minutes to a few hours Usually complete unless language areas involved MRI/MRA, CTA, vascular risk factors depend on vascular territory but are typically "negative" (eg, weakness, numbness, aphasia, visual loss); intensity is usually maximal at onset; consciousness usually preserved Migraine aura Positive and/or negative Up to 1 hour Complete Personal or family history of neurologic symptoms, most often visual and sensory, evolving gradually over 5 migraine https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 19/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate minutes (slower onset than TIA or focal seizure); slow spread of positive followed by negative symptoms, if present, is very characteristic; usually followed by headache Panic attack Palpitations, dyspnea, chest pain, Minutes to hours Complete History of anxiety or depressive symptoms, lightheadedness, sense of impending doom; associated hyperventilation may result in triggering events or stressors perioral and distal limb paresthesias Transient global amnesia Prominent anterograde amnesia (inability to form new memories) and variable 1 to 10 hours (mean 6 hours) Complete amnesia for the main episode; retrograde amnesia resolves within 24 hours Clinical diagnosis; negative MRI and toxicology screens retrograde amnesia; patient is disoriented in time, asking repetitive questions; other cognitive and motor functions spared; rare in adults younger than 50 years GTC: generalized tonic-clonic; EEG: electroencephalography; MRI: magnetic resonance imaging; ECG: electrocardiogram; MRA: magnetic resonance angiography; CTA: computed tomography angiography. Graphic 111740 Version 3.0 https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 20/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate Focal or nonfocal symptoms of transient neurologic attacks Focal symptoms Nonfocal symptoms Common disorders Seizure +++ ++ Transient ischemic attack ++++ + Migraine aura ++++ + Syncope 0 ++++ Less common disorders Vestibulopathy ++ ++ Metabolic + +++ "Tumor attacks" +++ + Multiple sclerosis ++++ + Psychiatric ++ ++ Nerve and nerve root ++++ 0 Transient global amnesia ++++ 0 Graphic 62326 Version 5.0 https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 21/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate Evaluation of patient presenting with acute symptoms of possible TIA or minor ischemic stroke This algorithm should be used in conjunction with UpToDate topics on the initial evaluation and management of TIA and ischemic stroke. CDUS: carotid duplex ultrasonography; CNS: central nervous system; CT: computed tomography; CTA: computed tomography angiography; ECG: electrocardiography; IV: intravenous; MRA: magnetic resonance angiography; MRI: magnetic resonance imaging; TIA: transient ischemic attack; TCD: transcranial Doppler. Patients who present within the appropriate time window after ischemic symptom onset and have a persistent neurologic deficit that is potentially disabling, despite https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 22/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate improvement of any degree, should be treated with intravenous thrombolysis and/or mechanical thrombectomy in the absence of other contraindications. Further management of these patients is similar to that of other patients with a potentially disabling stroke. Can begin aspirin and statin therapy while awaiting results of remaining diagnostic studies if imaging is negative for hemorrhage and other nonischemic cause of symptoms. Viable strategies include antihypertensive therapy, antithrombotic therapy, statin therapy, and lifestyle modification; select patients with symptomatic cervical internal carotid artery disease may benefit from carotid revascularization. Graphic 107065 Version 1.0 https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 23/24 7/5/23, 12:38 PM Differential diagnosis of transient ischemic attack and acute stroke - UpToDate Contributor Disclosures Louis R Caplan, MD No relevant financial relationship(s) with ineligible companies to disclose. Scott E Kasner, MD Grant/Research/Clinical Trial Support: Bayer [Stroke]; Bristol Meyers Squibb [Stroke]; Medtronic [Stroke]; WL Gore and Associates [Stroke]. Consultant/Advisory Boards: Abbvie [Stroke]; AstraZeneca [Stroke]; BMS [Stroke]; Diamedica [Stroke]; Medtronic [Stroke]. All of the relevant financial relationships listed have been mitigated. John F Dashe, MD, PhD No relevant financial relationship(s) with ineligible companies to disclose. Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence. Conflict of interest policy https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke/print 24/24