In our institute, carotid artery stenting (CAS) has been performed using GuardWire and Wallstent RP, regardless of plaque pathology. In this study, we evaluated our results (high-intensity area on diffusion-weighted imaging (DWI), stroke/death/myocardial infarction within 30 days, ipsilateral stroke/neurological death after 31 days, and retreatment after CAS). Between April 2005 and December 2009, 76 CAS procedures were performed on 74 patients. DWI obtained after CAS showed a high-intensity area in 13 of 75 procedures (17.3%). Two patients (2.6%) died of stroke and myocardial infarction within 30 days after CAS. One patient (1.3%) had symptomatic cerebral infarction; the other, intracranial hemorrhage. Ipsilateral stroke and neurological death after 31 days occurred in 1 patient (1.3%), who had ipsilateral cerebral infarction at 24 months. Retreatment after CAS was required in 2 patients (2.6%). CAS performed using GuardWire and Wallstent RP is an effective and safe procedure. It is important to achieve proficiency in the use of technical devices to perform successful CAS.
We reviewed the treatment results of cervical carotid artery stenting (CAS) for carotid stenosis with cerebral hemodynamic compromise evaluated by 123I-IMP single photon emission computed tomography (SPECT). We treated 10 cases of carotid stenosis with Stage II hemodynamic cerebral ischemia. Hemodynamic compromise was diagnosed by pre-treatment resting and acetazolamide-activated CBF-SPECT using 123I-IMP. There were 5 cases of symptomatic and 5 cases of asymptomatic carotid stenosis. Post-treatment CBF was evaluated 7 days after the procedure. In all cases, pre-operative Stage II hemodynamic compromise was improved at post-procedure SPECT. There were no cases of hyperperfusion syndrome (HPS), intracerebral hemorrhage or ischemic complications during or after the procedure. In patients with ipsilateral Stage II cerebral ischemia, the peri-operative countermeasure against HPS is very important. And in patients with contralateral side Stage II cerebral ischemia, it is necessary to consider how to cope with bradycardia and hypotension to prevent peri-procedural cerebral infarction.
Since distal embolism is a major complication of carotid artery stenting (CAS), pre-operative evaluation of plaque histology has become important. Though virtual histology IVUS (VH-IVUS) is a useful device for inspecting plaque morphology, evaluation of carotid plaque with VH-IVUS is controversial because it was developed for coronary arteries. We evaluated morphology of 6 carotid plaques with VH-IVUS during carotid endarterectomy (CEA). In addition, we performed balloon angioplasty on the extracted plaque (angioplasty-mimic) and evaluated a quantity of debris and the pathology of the plaque after angioplasty-mimic. Little debris was generated by PTA from the plaque of mainly fibrous and fibro-fatty lesions. On the other hand, there was much debris from plaque of mixed lesions, consisting of calcification and a necrotic core lesion. On pathological examination, a large amount of debris appeared to be isolated between the layer of calcified area and the necrotic core. Lesions that were classified as calcified on VH-IVUS analysis appeared to be mixed of pathology and very vulnerable.
Between January 2004 and December 2009, we performed carotid artery stenting (CAS) for 220 sides. Among them, we evaluated 142 sides of 136 cases at follow-up ＞1 year, and studied the long-term occurrence of recurrent stenosis (＞50% by ultrasound or angiography), ipsilateral ischemic stroke, unstable angina pectoris (u-AP) or acute myocardial infarction (AMI), and death. Over a median follow-up period of 36.6 months, the incidence of recurrent stenosis was 8.5% (12 sides), with only 1 side leading to neurological symptoms. Among them, 6 sides of recurrent stenosis occurred in the first 12 months after CAS. This suggests recurrent stenosis is caused by intima hyperplasia rather than by progressive atherosclerosis. Ipsilateral ischemic strokes occurred in 2.8% (4 sides), but only 1 side derived from carotid stenosis after stenting. U-AP and AMI occurred in 4.2% (6 cases) after CAS. Twelve cases resulted in death, though no death was caused by carotid stenosis or ischemic stroke. Stenting for carotid stenosis is an effective treatment to prevent stroke over long terms. Recurrent stenosis after CAS occurs more frequently than previous reports indicate. We should be aware of coronary disease events.
The symptoms of acute stroke patients with atherosclerotic intracranial vertebrobasilar occlusive lesions (IVBO) frequently worsen despite medical treatment. However, timing of percutaneous transluminal balloon angioplasty (PTA)/stenting is difficult to decide, especially when the symptoms are minimal. We investigated patient selection, procedure timing and problems of PTA/stenting for acute IVBO. We retrospectively reviewed 19 patients―6 with near occlusion (NO) and 13 with complete occlusion (CO)―who underwent urgent PTA/stenting (Group A). Deterioration of the symptoms was observed in 14 patients (74%). Technical success was achieved in 17 patients including PTA in 4 and stenting in 13 (NO 100% vs. CO 85%). Recurrent stroke did not occur in any of the patients, though 2 patients underwent re-treatment. Symptomatic complications occurred in 6 patients, including distal embolism in 3 (NO 1, CO 2), medullary hemorrhage in 1 (CO), hemorrhagic infarction in 1 (CO), and subacute thrombosis in 1 (CO). Favorable outcomes (mRS≦2) were obtained in 8 patients (NO 83% vs. CO 23%, P＜0.05). The causes of the poor outcome of CO were delay of the PTA/stenting and periprocedural complications. We also retrospectively reviewed 23 patients, 14 with high-grade stenosis, 3 with NO and 6 with CO, who underwent medical treatment in acute phase of the stroke (group B). Recurrent stroke occurred in 9 patients (10.6%/year). Eight patients underwent PTA/stenting in the subacute or chronic phase, and recurrent stroke did not occur. Analysis of the angiographic findings in patients with CO showed that symptoms seemed to deteriorate when the retrograde flow into the anterior inferior cerebellar artery was not recognized even if the initial symptoms were mild. Urgent PTA/stenting for the patients with NO is a safe and effective treatment option. However, the outcome of the patients with CO is unfavorable. Patient selection, procedure timing and reduction of the complications are critical factors to improve outcomes.
123I-iomazenil (IMZ)-SPECT is used as a tool to detect the viability of neuronal cells. We investigated the distribution of IMZ in the brain of patients suffering from moyamoya disease, comparing it with the images of MRI and the distribution of 123I-N-isopropyl-4-iodoamphetamin hydrochloride (IMP)-SPECT. In the present study, we investigated 5 patients (4 females and 1 male, aged 30 to 61) who received our modified surgery according to our strategy (EC-IC bypass surgery and/or EMS, EDAS) in our institution from July 2008 to November 2009. The initial symptoms were ischemic events in 4 patients, and bleeding in 1 patient. 123I-IMZ-SPECT was started 170 minutes after an injection of 123I-IMZ. The distribution of IMZ or IMP was analyzed by iSSP5 and NEUROFLEXER to obtain Z scores. The revascularization procedures were performed at the sites where cerebral blood flow (CBF) was significantly reduced and poor response to Diamox treatment was seen preoperatively. The uptake of 123I-IMZ-SPECT was lower on the symptomatic side than on the asymptomatic side. Only in the region where 123I-IMZ uptake had been preserved preoperatively, the surgery induced a successful restoration of CBF postoperatively. These results strongly suggest that 123I-IMZ-SPECT is useful for evaluation of preoperative neuronal viability of the patients with moyamoya disease as well as preoperative prediction of surgical efficacy.
We evaluated surgical treatment for angiomatous lesion developing after gamma knife radiosurgery (GKS) for arteriovenous malformation (AVM) by retrospectively examining the medical records of 3 female patients aged 20 to 52 years (mean 31.3 years) at the time of GKS, who developed symptomatic angiomatous lesion associated with severe surrounding brain edema 9-11 years after GKS. Angiomatous lesions were dark red and well demarcated from the brain. Bleeding during resection was slight and easily controlled, but the angiomatous lesions were very fragile and difficult to remove en bloc. Therefore, total removal is not easy in the case of angiomatous lesions in deep locations such as interhemispheric sites with lateral extension. Angiomatous lesion developing after GKS for AVM is rare but becomes progressively symptomatic with severe surrounding brain edema, and the only treatment is surgery.
Aneurysms of the proximal anterior cerebral artery (A1) are rare. We investigated the clinical and angiographical characteristics, and treatment outcomes of A1 aneurysms by reviewing a total of 989 cases of ruptured or unruptured cerebral aneurysms treated with surgical clipping or coil embolization in our department and identified 12 cases of A1 aneurysms (1.2%), including 4 ruptured and 8 unruptured aneurysms. Three of the 4 patients with ruptured aneurysm were Grade IV or V in the classification of the World Federation of Neurosurgical Societies. Five of the 8 cases of unruptured A1 aneurysm were identified during examination for subarachnoid hemorrhage due to ruptured aneurysm at other sites. The A1 aneurysms were located on the proximal segment in 9 cases and projected posteriorly or superiorly in 11 cases. Symptomatic complications occurred in 2 of the 10 cases treated by surgical clipping: cerebral infarction of the genu of internal capsule causing transient motor aphasia in 1 patient, and visual field disturbance due to obstruction of a perforator originating from the A1 in the other patient. Considering the anatomical relationship, any perforator originating from the A1 should be carefully manipulated at surgical clipping.
In recent years, treatments for the posterior circulation aneurysms have shifted to endovascular treatment. However, there are cases requiring surgical procedures in which endovascular treatment is not applicable. We encountered 10 surgically treated patients with the posterior circulation aneurysms, including 6 subarachnoid hemorrhage cases, in the past 7 years. In 3 cases of posterior cerebral artery (PCA) aneurysms, we mainly used the transmastoid approach, bypass and trapping technique. For 5 patients with vertebro-basilar (V-B) aneurysms, skull base approach and/or bypass technique were required. In 2 cases of posterior inferior cerebellar artery (PICA) dissecting aneurysms, occipital artery (OA)-PICA bypass with trapping of PICA was performed. The outcomes of these 10 patients were evaluated using Glasgow Outcome Scale. Six patients achieved good recovery, 3 patients remained severely disabled, and 1 patient was in a persistent vegetative state. In performing surgery in this field, skull base approaches and bypass technique are crucial, and we have to make effort to train ourselves.
An 85-year-old woman had been suffering from left oculomotor palsy for 5 years and developed left facial palsy 6 months previous to presenting. She was diagnosed with a giant aneurysm of the left internal carotid artery in the cavernous portion extending into the middle cranial fossa. The left internal carotid artery was sacrificed by endovascular technique following balloon occlusion test. The internal carotid artery giant aneurysm became larger 2 years after endovascular occlusion. In the second operation, the distal internal carotid artery and the ophthalmic artery were occluded by clipping and then the giant aneurysm was decompressed by opening the aneurysm wall and removing a clot. Our results suggest that giant aneurysms located near the collateral feeding vessel following proximal parent vessel occlusion should be trapped by clipping.
We report the case of a patient with a ruptured cerebral aneurysm who consecutively repeated early recurrence after clipping and coil embolization and required high-flow bypass-combined trapping. The patient was a 48-year-old female brought to our hospital by ambulance for acute headache. Subarachnoid hemorrhage and aneurysm of the right internal artery (ICA)-posterior communicating artery (PcomA) were observed on CT, and clipping was performed on the admission day. The lesion was a cerebral aneurysm with a very thin wall. Clipping was applied uneventfully, but when a clip applied deeply to the blade root was re-applied at a shallower site, the aneurysm ruptured at the neck. Re-clipping was repeated 5 times, and was finally successful on pressing a weakly curved clip to the ICA. However, recurrence of the aneurysm was observed on angiography performed after 25 days. Coiling was performed the following day, and the recurrent aneurysm was completely filled, but recurrence occurred again after about 3 months. Considering the vulnerability of the neck, high-flow bypass-combined ICA trapping was performed, and the aneurysm could be finally treated. An aneurysm with a thin neck wall requires a careful surgical technique. When aneurysm neck tissue is injured by repeated clipping, the aneurysm may recur early after treatment. For such a recurrent aneurysm, trapping should be selected, not coiling. A lesion that appears to be a common aneurysm with a thin wall may actually be a dissecting aneurysm in some cases, for which high-flow bypass-combined trapping is necessary from the beginning. Techniques and preparation to perform such surgeries at any time are necessary.