Middle cerebral artery occlusion (MCAO) mainly happen as a result of thromboembolism. This occurs more often in the middle cerebral artery (MCA) than in the other cerebral arteries, as the former branches off directly from the internal carotid artery. The MCA supplies part of the cerebral cortex, as well as the basal ganglia and internal capsules. Thus MCAO leads to an MCA territory stroke, which presents with a wide range of neurological manifestations. The ischemic strokes that arise from MCAO are the result of cell hypoxia and energy depletion, which eventually lead to cytotoxic edema of the affected area [1] [2] [3].

The typical findings in MCA territory stroke are contralateral hemiparesis and contralateral hemisensory loss. The weakness experienced in MCA territory strokes is typically more pronounced in the upper limbs and face than in the lower limbs. Furthermore, patients may have homonymous hemianopsia. If the stroke affects the dominant hemisphere, patients may also present with expressive, receptive, or global aphasia, depending on whether the infarcted area supplied by the MCA is anterior, posterior, or total. If the stroke affects the non-dominant hemisphere, patients may exhibit neglect. Other possible manifestations of MCAO and MCA territory stroke are agnosia and gaze preference to the side of the lesion.

• Asymptomatic

  Only one patient developed asymptomatic subarachnoid hemorrhage, which was completely resolved before discharge. Conclusions: Our initial experience suggests that successful recanalization of M2 and M3 occlusion with EVT is feasible and safe. [neurology.org]

  We present a case of successful endovascular right middle cerebral (MCA) embolectomy in a patient with undetected previously asymptomatic IAS one month after coronary artery bypass surgery. [jneuro.com]

• Hemianopsia

  Furthermore, patients may have homonymous hemianopsia. [symptoma.com]

  Click Image to Enlarge Clinical symptoms associated with occlusion of the posterior cerebral artery depend on the location of the occlusion and may include thalamic syndrome, thalamic perforate syndrome, Weber’s syndrome, contralateral hemplegia, hemianopsia [strokecenter.org]

  Contralateral homonymous hemianopsia is often present. See also [ edit ] Leptomeningeal collateral circulation References [ edit ] ^ Moore KL, Dalley AR. Clinically Oriented Anatomy, 4th Ed., Lippincott Williams & Wilkins, Toronto. Copyright 1999. [en.wikipedia.org]

• Dyslexia

  […] of the occlusion and may include thalamic syndrome, thalamic perforate syndrome, Weber’s syndrome, contralateral hemplegia, hemianopsia and a variety of other symptoms, including including color blindness, failure to see to-and-fro movements, verbal dyslexia [strokecenter.org]

• Stroke

  If the stroke affects the non-dominant hemisphere, patients may exhibit neglect. Other possible manifestations of MCAO and MCA territory stroke are agnosia and gaze preference to the side of the lesion. [symptoma.com]

  International Journal of Stroke © 2013 World Stroke Organization. [ncbi.nlm.nih.gov]

• Aphasia

  If the stroke affects the dominant hemisphere, patients may also present with expressive, receptive, or global aphasia, depending on whether the infarcted area supplied by the MCA is anterior, posterior, or total. [symptoma.com]

  At 4 months' follow-up, the patient was living at home, was ambulating, and had excellent comprehension with mild expressive aphasia. [ncbi.nlm.nih.gov]

  Strokes involving the middle cerebral artery often result in sensory deficits and muscle weakness on the contralateral side of the body; when a middle cerebral artery stroke is in the dominant side of the brain, the patient can also have aphasia. [medical-dictionary.thefreedictionary.com]

  The neurological deficit will depend on the extent of the infarct and hemispheric dominance, and include: contralateral hemiparesis contralateral hemisensory loss hemianopia aphasia: if the dominant hemisphere is involved; may be expressive in anterior [radiopaedia.org]

  Damage to the dominant hemisphere (usually the left hemisphere) results in aphasia i.e. [en.wikipedia.org]

• Headache

  The last was a 49-year-old female patient presented with a 1-month history of right-sided headache. Atherosclerotic middle cerebral artery occlusion. [ncbi.nlm.nih.gov]

  Inhibits platelet adenosine uptake and cyclo-oxygenase [72] Twice daily dosing Headaches are a common adverse effect, which may limit tolerability of therapy [73] Clopidogrel Blocks platelet adenosine diphosphate (ADP) P2Y12 receptor [74] Avoidance of [emedicine.medscape.com]

• Homonymous Hemianopsia

  Furthermore, patients may have homonymous hemianopsia. [symptoma.com]

  Contralateral homonymous hemianopsia is often present. See also [ edit ] Leptomeningeal collateral circulation References [ edit ] ^ Moore KL, Dalley AR. Clinically Oriented Anatomy, 4th Ed., Lippincott Williams & Wilkins, Toronto. Copyright 1999. [en.wikipedia.org]

• Expressive Aphasia

  At 4 months' follow-up, the patient was living at home, was ambulating, and had excellent comprehension with mild expressive aphasia. [ncbi.nlm.nih.gov]

When evaluating patients with middle cerebral artery occlusion, medical imaging is a key. The imaging studies often conducted are:

• Computed tomography (CT): This may be carried out with or without a contrast agent. MCAO leads to the visualization of the MCA at the point of the occlusion, as a hyperdense lesion immediately after the thromboembolic event [4]. Cytotoxic edema will be most evident in the distortion of grey matter, and the border between grey and white matter becomes less prominent [5] [6].
• Magnetic resonance imaging (MRI): Occlusion of the MCA and tissue ischemia can be observed via this technique.

In the assessment of a patient with an ischemic stroke, it is important to identify what risk factors the individual carries. Non-modifiable risk factors include age, sex, ethnicity, and genetic traits related to family history of strokes and transient ischemic attacks (TIAs). Modifiable risk factors include hypertension, obesity, cardiac conditions such as atrial fibrillation and valvular heart disease, diabetes mellitus, and high cholesterol levels [7].

Further studies that may be carried out include a complete blood count, basic metabolic panel, clotting studies, toxicology screening, and lumbar puncture.

The risk of SICH was significantly increased in the active treatment arms (11% vs 2%, OR 4.6, 95% CI 1.3 to 16, p=0.02). [ncbi.nlm.nih.gov]

Different degrees of LA differentially affect clinical outcome and prognosis in patients with middle cerebral artery occlusion following intravenous thrombolytic. Moderate to severe LA is a risk factor of poor prognosis. [ncbi.nlm.nih.gov]

The presence of a co-existing anomalous collateral artery in the present case suggests a congenital etiology of the focal middle cerebral artery occlusion. [ncbi.nlm.nih.gov]

Sex differences in stroke epidemiology: A systematic review. Stroke, 40 (4), pp. 1082-1090. Arboix, A., Alio, J. (2010). Cardioembolic stroke: Clinical features, specific cardiac disorders and prognosis. Curr. Cardiol. Rev., 6 (3), 150-161. [degruyter.com]

Stroke epidemiology in the developing world. Lancet 2005;365:2160-2161. Murray CJ, Lopez AD. Mortality by cause for eight regions of the world: Global Burden of Disease Study. Lancet 1997;349:1269-1276. Donnan GA, Fisher M, Macleod M, Davis SM. [medigraphic.com]

[…] intraluminal filament model of middle cerebral artery occlusion (tMCAO) has been questioned due to distinct cerebral blood flow profiles upon reperfusion between tMCAO (abrupt reperfusion) and alteplase treatment (gradual reperfusion), resulting in differing pathophysiologies [ncbi.nlm.nih.gov]

Malignant middle cerebral artery (MCA) infarction: Pathophysiology, diagnosis and management. Postgrad Med. J., 86, 235-242. [degruyter.com]

Neurological deficit and infarction were presumably prevented by immediate administration of pentobarbital followed by extracranial-intracranial bypass. [ncbi.nlm.nih.gov]

Interventions are directed at preventing unplanned bowel movements, preventing constipation, and promoting efficient and effective bowel care. [emedicine.medscape.com]

1. Donnan GA, Fisher M, Macleod M, Davis SM. Stroke. Lancet. 2008;371(9624):1612-1623.
2. Dirnagl U, Iadecola C, Moskowitz MA. Pathobiology of ischaemic stroke: an integrated view. Trends Neurosci. 1999;22(9):391-397.
3. Yuan J, Yankner BA. Apoptosis in the nervous system. Nature. 2000;407(6805):802-809.
4. Pressman BD, Tourje EJ, Thompson JR. An early CT sign of ischemic infarction: increased density in a cerebral artery. AJR Am J Roentgenol. 1987;149(3):583-586.
5. Moulin T, Cattin F, Crépin-Leblond T, et al. Early CT signs in acute middle cerebral artery infarction: predictive value for subsequent infarct locations and outcome. Neurology. 1996;47(2):366-375.
6. Nakano S, Iseda T, Kawano H, Yoneyama T, Ikeda T, Wakisaka S. Correlation of early CT signs in the deep middle cerebral artery territories with angiographically confirmed site of arterial occlusion. AJNR Am J Neuroradiol. 2001;22(4):654-659.
7. Goldstein LB, Bushnell CD, Adams RJ, et al. Guidelines for the primary prevention of stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2011;42(2):517-584.