Revascularisation Procedures For TIA
Encephaloduroarteriosynangiosis (EDAS), which involves the transposition of a segment of a scalp artery onto the surface of the brain, is a surgical treatment aimed at improving collateral blood flow.
Generally, it is advocated in children with Moya Moya disease, but has shown promising early results in the treatment of adult patients with moyamoya disease (MMD) and more recently in patients with intracranial atherosclerotic steno-occlusive disease. The rates of stroke after EDAS are lower than those reported with other treatments, including intensive medical therapy in patients with TIA.
CT and MRI are the recommended modality to diagnose TIA and image ischemic lesions. In addition, Transcranial Doppler sonography (TCD) and Digital Subtraction Angiography (DSA) are two acceptable alternatives for diagnosing TIA patients.
PET imaging can be used to quantify areas of altered cerebral blood flow and abnormal glucose and oxygen metabolism. This can be used to elucidate areas of ischemic penumbra and infarcted tissue. It is used as an imaging biomarker to detect high-risk carotid plaques
2. STA-MCA Anastomosis Surgery
Direct revascularization (STA-MCA bypass) involves use of a branch of a scalp artery (STA) for direct anastomosis (connection) to a branch of the brain artery (MCA) on the outer surface of the brain. This procedure benefits patients by providing an immediate improvement in blood supply to the brain.
This can be done as a stand alone procedure or can be combined with EDAS procedure.
What is in the future for stroke treatment?
At present, studies are being performed on other drugs which dissolve clots. These drugs are given either in the veins (like TPA) or into the clogged artery directly. These studies are done for determining which stroke patients may benefit from this aggressive treatment form. New medications are also being tested which help to slow the nerve cells’ degeneration which are oxygen deprived during a stroke. These drugs are known as “neuroprotective” agents, for example: sipatrigine. Chlormethiazole is another example. Chlormethiazole works by modifying the genes expression inside the brain. (Genes generate proteins determining a person’s makeup.) Lastly, stem cells having the potential to develop into various different organs, are being used for trying to replace brain cells that are damaged by an earlier stroke. In several academic medical centres, few of these experimental agents may be offered in the setting of a clinical trial. Although new therapies for the treatment of patients following a stroke are on the verge, they aren’t yet perfect and complete function may not be restored to a stroke victim.
This 46 years old patient presented with repeated episodes of giddiness and transient limb weakness (called as transient Ischemic attacks). He was hypertensive, diabetic and heavy smoker. The carotid angiography showed severe stenosis of the internal carotid artery at its origin causing compromise of brain circulation. The patient preferred carotid stenting over open surgery.
Following successful carotid stenting by our interventional neuroradiologist, patient made uneventful recovery. His symptoms disappeared completely. In addition, he needed complete change in the lifestyle.
This 30 year old patient presented with transient limb weakness. He had suffered with similar episode 3 years ago, from which he had improved significantly. He was non-diabetic, but was hypertensive and heavy smoker. MRI with MR angiography, cerebral angiography and carotid showed a large floating thrombus in the internal carotid artery at its origin.
SURGERY: He underwent an emergency open carotid endarterectomy with excellent postoperative recovery. His limb weakness has not recurred or deteriorated since then.