MEDICAL SCIENCES
Management of Cerebrovascular Steno-Occlusive Disease Contemporary multidisciplinary approach Patients with steno-occlusive cerebrovascular disease are at risk of ischemic symptoms from haemodynamic insufficiency in the presence of reversible hypoperfusion, exhausted autoregulation and impaired vasodilatory reserve. Multidisciplinary management approach includes blood pressure management, antithrombotic therapy, treatment of underlying brain-body interactions targeted at optimising cerebral blood flow and oxygen delivery, and revascularisation procedures. Benjamin Wai Yue Lo, Neurosurgeon & ICU Specialist
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atients with symptomatic stenoocclusive disease have a risk of recurrent stroke of at least 10-15 per cent within 5 years. Progressive atherosclerosis of internal carotid artery (ICA) or middle cerebral artery (MCA) is the most common cause of impaired distal cerebral perfusion with cerebral misery hypoperfusion (Figure 1, Table 1).
Cerebral Hypoperfusion & Collateral Circulation
In the setting of cerebral hypoperfusion, recurrent ischaemic events occur depending on the following factors: (1) amount of collateral cerebral circulation; (2) extent of haemodynamic impairment; (3) age; (4) cardiac status; (5) presence of metabolic syndrome of hypertension, hyperlipidemia and insulin resistance; (6) factors affecting coagulation, blood
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A SI A N H O S P I T A L & H EA LT HCA R E M A N AGE M E N T
oxygen carrying capacity and delivery (such as anaemia and other haematology disorders, systemic infections and sepsis, renal and hepatic disorders). In addition to the traditional cerebral ischaemic symptomatology pertaining to the affected vascular territory (Table 2), orthostatic symptoms, syncope, transient global amnesia, episodic limb shaking and watershed infarction are possible. In states of misery perfusion, compensatory cerebral vasodilation is not possible as the cerebral autoregulatory capacity is exhausted and, as a result, cerebral blood flow decreases proportionally with cerebral perfusion pressure (Figure 1). Possible cerebral collateral circulation routes include: (1) contralateral internal carotid artery (ICA) through anterior communicating artery; (2) posterior circulation via posterior communicating artery; (3)
IS S UE - 55, 2022
