Current perspectives and future directions of the treatment for non acute intracranial artery occlusion / 中国综合临床

Non-acute intracranial artery total occlusion can lead to severe neurological defect and high recurrence rate of stroke.At present, there is no effective treatment recommended by the guidelines.Traditional treatment methods include medical therapy, extracranial-intracranial bypass surgery and minimally invasive endovascular recanalization therapy.In recent years, with the development of microsurgical vascular anastomosis technique and neurosurgical intervention, and the development of interventional materials, the treatment of non-acute intracranial artery total occlusion has become a hot spots.In this paper, the concept of non on-acute intracranial artery total occlusion, medical therapy, extracranial-intracranial bypass surgery and endovascular interventional therapy are reviewed.

Arachnoid Membrane Suturing for Prevention of Subdural Fluid Collection in Extracranial-intracranial Bypass Surgery

OBJECTIVE: Water-tight closure of the dura in extracranial-intracranial (EC-IC) bypass is impossible because the superficial temporal artery (STA) must run through the dural defect. Consequently, subdural hygroma and subcutaneous cerebrospinal fluid (CSF) collection frequently occur postoperatively. To reduce these complications, we prospectively performed suturing of the arachnoid membrane after STA-middle cerebral artery (STA-MCA) and evaluated the clinical usefulness. MATERIALS AND METHODS: Between Mar. 2005 and Oct. 2010, extracranial-intracranial arterial bypass (EIAB) with/without encephalo-myo-synangiosis was performed in 88 cases (male : female = 53 : 35). As a control group, 51 patients (57 sides) underwent conventional bypass surgery without closure of the arachnoid membrane. Postoperative computed tomography (CT) scan was performed twice in three days and seven days later, respectively, for evaluation of the presence of subdural fluid collection and other mass lesions. RESULTS: The surgical result was excellent, with no newly developing ischemic event until recent follow-up. The additional time needed for arachnoid suture was five to ten minutes, when three to eight sutures were required. Post-operative subdural fluid collection was not seen on follow-up computed tomography scans in all patients. CONCLUSION: Arachnoid suturing is simple, safe, and effective for prevention of subdural fluid collection in EC-IC bypass surgery, especially the vulnerable ischemic hemisphere.

Management Options and Prognosis of Carotid Artery Occlusive Disease / 대한뇌혈관외과학회지

OBJECT: The effective management of carotid occlusive disease still remains a challenge to neurosurgeons. The authors analyzed the series of management of carotid occlusive disease in order to determine whether our management strategy affected patient's clinical outcomes. Methods of identifying patients who stand to benefit from this therapy need to be established. METHOD: Clinical findings, management, complications and outcome in 52 patients with high grade carotid stenosis of at least 70% and occlusion were investigated. The patients were treated by percutaneous transluminal angioplasty (PTA) and/or stent (PTAS), Extracranial-Intracranial (EC-IC) bypass surgery, carotid endarterectomy (CEA) according to the neurologic status, medical condition, severerity of stenosis, collateral blood flow. RESULTS: The causes of carotid stenosis were 40 atherosclerosis arteries, 9 spontaneous dissections and 2 traumas, 1 fibomuscular dysplasia (FMD) of 52 patients. 9 patients were treated by PTA alone, and 28 patients by PTAS, 9 patients by EC-IC bypass surgery, 3 patients by PTAS followed by EC-IC bypass surgery, 3 patients by CEA. For the outcome according to management, 26 patients (100% of all bypass surgery only and CEA, 35% of all PTA and PTAS) recovered excellently, 14 patients (35% of all PTA and PTAS) had a good outcome. 2 patients died. CONCLUSION: The results of this study suggest that PTAS should be a useful and effective treatment method for some patients with the severe atherosclerotic stenosis or carotid artery dissection. However, the surgical management must be considered for the high risk, high grade carotid stenosis patients with collateral blood flow, and with or without mild or moderate deficits.

Surgical Treatment of Cerebral Ischemia / 대한뇌혈관외과학회지

Since the proportion of ischemic stroke has been increasing compared to hemorrhagic stroke in our country, only recently the medical community began to systematically emphasize the importance of managing ischemic stroke patients as aggressively as possibly in an attempt to improve outcome and facilitate the development of useful treatment algorithms. It is necessary to estimate initially which vascular territory among large or small artery is compromised for planning treatment strategies in patients with acute ischemic stroke. The author focuses on the efficient assessment and surgical management of patients with acute ischemic stroke by reviewing the operative techniques and perioperative management of carotid endarterectomy and extracranial-intracranial bypass surgery

Effectiveness of Bypass Surgery in Treatment and Prevention for Cerebrovascular Occlusive Disease

To study the effect of extracranial-intracranial(EC/IC) bypass on symptomatic patients with hemodynamic cerebral ischemia, we prospectively reviewed 76 patients who underwent EC/IC bypass surgery in patients with occlusive cerebrovascular disease. A series of 76 patients treated in a 7 years period met following criteria. (1) symptomatic internal carotid artery(ICA) or middle cerebral artery(MCA) obstruction or stenosis over 80%. (2) decrease in basal cerebral blood flow(CBF) over 10%. (3) decreased reactivity of CBF in response to acetazolamide. Among these, the types of ischemic episodes were transient ischemic attack(TIA) or reversible ischemic neurological deficit(RIND) in 39, minor stroke in 22, and major stroke in 15. Based on our criteria, superficial temporal artery(STA)-MCA anastomosis was performed in 67 cases and EC-IC bypass grafting using saphenous vein or radial artery in 9. Average follow up period was 26 months(3 months~7 year). Patency of bypass was confirmed by postoperative angiography or magnetic resonence angiography(MRA) in all case except four cases. Of the 72 patients with patiency of bypass, 68 patients(94%) have had an excellent to good outcome with improvement of preoperative neurologic or cognitive dysfunction, 3 patients showed no improvement of preoperative neurologic symptoms and remaining one patient had new developed deficit. All 72 patients with patency of bypass had experienced no further cerebral ischemic events during following period. Postoperative significant improvement of CBF to acetazolamide was showed in 68 cases(94%) of the 72 cases with patency of bypass, while the basal CBF showed significant improved in 31cases. Postoperative permanent neurologic deficit occurred only in one. In view of these finding, the author suggest that EC-IC bypass surgery is a reliable and resonably safe method for establishing new pathways of collateral circulation to the brain and to be considered as an appropriate therapy for improvement of the cerebrovascular reserve capacity in patients with hemodynamic cerebral ischemia, defined using the strict selection criteria employed in this study.

Extracranial-Intracranial Bypass Surgery: Surgical Techniques and Perioperative Management / 대한뇌혈관학회지

Options for extracranial-intracranial bypass surgery of anterior circulation include saphenous vein grafts, occipital to middle cerebral artery (MCA) anastomosis, and most commonly superficial temporal artery (STA) to MCA anastomosis. Although less common, posterior circulation revascularization has been successfully peformed. The operative techniques and perioperative management such as anesthetic techniques and electrophysiologic monitoring are reviewed. Finally the author's surgical experiences of STA-MCA anastomosis in 30 patients with symptomatic internal carotid artery or MCA stenoocclusion are reported.

Current Indication of Extracranial-Intracranial Bypass Surgery / 대한뇌혈관학회지

Since the negative results of the international extracranical-intracranial bypass surgery (EIBS), this procedure is rarely employed in the treatment of patients with ischemic stroke. However, recent evidence suggests that patients with hemodynamic cerebral ischemia (HCI) are at particular risk for subsequent stroke compared to those with similar occlusive lesion but intact cerebrovascular reserve (CVR). Furthermore, several investigators have suggested that EIBS is effective in preventing recurrent ischemic attacks in patients with HCI due to occlusive disease and insufficient collateral blood supply. In addition, EIBS has been frequently used for the patients with moyamoya disease and for the patients who need therapeutic occlusion or sacrifice of a parent vessel during the treatment of complex intra or extracranial aneurysms or cranial base tumors. Based on a review of literature the rationale and the indication of EIBS will be summaried.

Improvement of Cerebrovascular Reserve Capacity by Bypass Surgery in Patients with Hemodynamic Cerebral Ischemia

To study the effect of extracranial-intracranial(EC/IC) bypass on symptomatic patients with hemodynamic cerebral ischemia, we prospectively reviewed 14 patients who underwent EC/IC bypass surgery. A series of 14 patients treated in a 2 years period met the following criteria, 1) symptomatic internal carotid artery(ICA) or middle cerebral aetery(MCA) obstruction or stenosis over 80M, 2) decrease in basal cerebral blood flow(CBF) over 10%, 3) hyporeactivity to acetazolimide of CBF Amomg these, the type of ischemic episode was transient ischemic attack(TIA) or reversible ischemic neurological deficit(RIND) in 4, minor stroke in 8, and major stroke in 2. Of these, 10 patients had multiple episode of ischemic attack. CT or MRI were showed infarction of the MCA territory in 3, border zone infarction in 5, basal ganglia infarction in 2 and multiple lacunar infarction in 4. Based on our criteria, superficial temporal artery(STA)-MCA anastomosis was performed in 13 cases and EC-IC bypass grafting using radial artery in one. Average follow up period was 24 months. Postoperative course was uneventful in 12 patients. One patient suffered a postoperative stroke with complete recovery and another suffered operative wound infection. Of the 14 patients 12(85.7 % ) have had an excellent to good outcome with complete resolution or significant improvement of preoperative neurologic symptom, remaining two show no improvement of preoperative neurologic deficit. Bypass patency was confirmed by postoperative angiography in all cases except for one. Postoperative follow up studies of the basal CBF and response to the acetazolamide of the CBF showed significant increased CBF activity to acetazolamide in 12 cases(85. 7%) while the basal CBF was essentially unchanged in all cases except for two. In view of these finding, the authors suggest that EC-IC bypass surgery to be considered as an appropritate therapy for improvement of the cerebrovascular reserve capacity in patients with hemodynamic cerebral ischemia, defined using the strict selection criteria employed in this study.