Relationship between magnetic resonance angiography-diffusion-weighted imaging mismatch and clinical outcome in endovascular treatment for acute ischemic stroke: subgroup analysis of the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism--Japan Registry.

BACKGROUND: The presence or absence of the penumbra area is important when performing reperfusion therapy in patients with acute ischemic stroke. As a predictor of this penumbra area, magnetic resonance angiography (MRA)-diffusion-weighted imaging (DWI) mismatch is attracting attention. The usefulness of MRA-DWI mismatch (MDM) using the DWI-Alberta Stroke Program Early Computed Tomography Score (ASPECTS) in endovascular treatment (EVT) of patients with cerebral large vessel occlusion was evaluated. METHODS: Of 1442 patients registered in the Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism-Japan Registry between July 1, 2010 and June 30, 2011 who presented to the hospital within 24 hours of the onset of acute cerebral infarction because of cerebral large vessel occlusion, 188 patients who had internal carotid artery or middle cerebral artery occlusion and achieved recanalization with EVT were included. Of these, 71 patients underwent intracranial EVT because intravenous recombinant tissue plasminogen activator therapy was ineffective. The associations between the presence or absence of MDM (MDM-positive [MDM-P], DWI-ASPECTS≥6; MDM-negative [MDM-N], DWI-ASPECTS<6) and 90-day prognosis (modified Rankin Scale [mRS]) and symptomatic intracranial hemorrhage (sICH) were examined. RESULTS: Of the 188 patients analyzed, the time from symptom onset to admission was within 3 hours in 143 patients, 3-8 hours in 36 patients, and 8 hours or more in 9 patients. The time from the onset was within 3 hours in 118 patients in the MDM-P and 25 patients in the MDM-N cases. Favorable outcomes (mRS score≤2 at 90 days) were seen in 63 patients (53.4%) in the MDM-P group and 7 patients (28.0%) in the MDM-N group, showing a significantly more favorable clinical outcome in the MDM-P group (P=.027). The incidence of sICH was significantly lower in the MDM-P group (MDM-P group 3.4%, MDM-P group 20.0%; P=.009). The time from the onset was 3-8 hours in 29 patients in the MDM-P group and in 7 patients in the MDM-N group. Favorable outcomes were seen in 12 patients (41.4%) in the MDM-P group and 2 patients (28.6%) in the MDM-N group, with no significant difference between the 2 groups. No patients had sICH. The patients admitted 8 hours or more after the onset were all MDM-P. Five patients (55.6%) had a favorable outcome. CONCLUSIONS: This study demonstrated the safety and efficacy of EVT in MDM-P patients within 3 hours of symptom onset. Although the ratio of patients who had a favorable outcome was high in the MDM-P patients admitted 3-8 hours after the onset, the difference was not significant.

Recent trends in neuroendovascular therapy in Japan: analysis of a nationwide survey--Japanese Registry of Neuroendovascular Therapy (JR-NET) 1 and 2.

The present study retrospectively analyzed the database of the Japanese Registry of Neuroendovascular Therapy 1 and 2 (JR-NET1&2) to determine annual trends, including adverse events and clinical outcomes at 30 days after undergoing neuroendovascular therapy. JR-NET1&2 are surveys that targeted all patients in Japan who underwent neuroendovascular therapy delivered by physicians certified by the Japanese Society of Neuroendovascular Therapy (JSNET) between 2005 and 2009. Medical information about the patients was anonymized and retrospectively registered via a website. Data from 32,608 patients were analyzed. The number of treated patients constantly increased from 5,040 in 2005 to 7,406 in 2009 and the rate of octogenarians increased from 7.0% in 2005 to 10.4% in 2009. The proportion of procedures remained relatively constant, but ratios of angioplasty slightly increased from 32.8% in 2005 to 33.7% in 2009. Procedural complications were associated more frequently with acute stroke (9.6%), ruptured aneurysms (7.4%), intracranial artery disease (ICAD) (5.4%), and arteriovenous malformation (AVM, 5.2%). The number of patients requiring neuroendovascular treatment in Japan is increasing and the outcomes of such therapy are clinically acceptable. Details of each type of treatment will be investigated in sub-analyses of the database.

Efficacy of endovascular treatment for acute cerebral large-vessel occlusion: analysis of nationwide prospective registry.

BACKGROUND: The aim of this nationwide, prospective registry of acute cerebral large-vessel occlusion was to assess the efficacy of endovascular treatment (EVT) on outcome in the "real-world" settings. METHODS: Medical information of the patients was anonymized and registered prospectively through a Web site from 84 medical centers in Japan. Reperfusion of the affected arteries was evaluated by the Thrombolysis in Cerebral Infarction grade on cerebral angiography or by the modified Mori grade on magnetic resonance angiography. Clinical outcome was evaluated by modified Rankin Scale (mRS) at 90 days after onset. Symptomatic intracranial hemorrhage and procedure-related complications were also analyzed. RESULTS: Among intravenous tissue plasminogen activator (IV t-PA)-failed patients, no significant difference in favorable outcome was seen with or without EVT overall (41.7% versus 36.8%, P = .55). However, EVT significantly increased favorable outcomes (mRS score 0-2) in patients with internal carotid artery (ICA)/middle cerebral artery M1/basilar artery (BA) occlusion (41.3% versus 20.5%, P = .019). In contrast, among t-PA-ineligible patients, EVT significantly increased favorable outcomes overall (29.1% versus 19.5%; odds ratio, 1.70; P = .007). Furthermore, favorable outcomes were more common in patients with ICA/M1/BA occlusion (29.0% versus 10.3%; odds ratio, 3.56; P < .0001). Multivariate analysis also confirmed the efficacy of IV t-PA, EVT, and their combination for favorable outcome. CONCLUSIONS: EVT significantly improved clinical outcomes in IV t-PA-failed and t-PA-ineligible patients with ICA/M1/BA occlusion. These findings support the introduction of EVT for acute proximal artery occlusion.

Recent trends in neuroendovascular therapy in Japan: analysis of a nationwide survey--Japanese Registry of Neuroendovascular Therapy (JR-NET) 1 and 2.

The present study retrospectively analyzed the database of the Japanese Registry of Neuroendovascular Therapy 1 and 2 (JR-NET1&2) to determine annual trends, including adverse events and clinical outcomes at 30 days after undergoing neuroendovascular therapy. JR-NET1&2 are surveys that targeted all patients in Japan who underwent neuroendovascular therapy delivered by physicians certified by the Japanese Society of Neuroendovascular Therapy (JSNET) between 2005 and 2009. Medical information about the patients was anonymized and retrospectively registered via a website. Data from 32,608 patients were analyzed. The number of treated patients constantly increased from 5,040 in 2005 to 7,406 in 2009 and the rate of octogenarians increased from 7.0% in 2005 to 10.4% in 2009. The proportion of procedures remained relatively constant, but ratios of angioplasty slightly increased from 32.8% in 2005 to 33.7% in 2009. Procedural complications were associated more frequently with acute stroke (9.6%), ruptured aneurysms (7.4%), intracranial artery disease (ICAD) (5.4%), and arteriovenous malformation (AVM, 5.2%). The number of patients requiring neuroendovascular treatment in Japan is increasing and the outcomes of such therapy are clinically acceptable. Details of each type of treatment will be investigated in sub-analyses of the database.

Editorial: «Interventional Neuroradiology: a Neuroscience sub-specialty?¼.

Interventional Neuroradiology (INR) is not bound by the classical limits of a speciality, and is not restricted by standard formats of teaching and education. Open and naturally linked towards neurosciences, INR has become a unique source of novel ideas for research, development and progress allowing new and improved approaches to challenging pathologies resulting in better anatomo-clinical results. Opening INR to Neurosciences is the best way to keep it alive and growing. Anchored in Neuroradiology, at the crossroad of neurosciences, INR will further participate to progress and innovation as it has often been in the past.

«Interventional Neuroradiology: a neuroscience sub-specialty?¼.

Interventional Neuroradiology (INR) is not bound by the classical limits of a specialty, and is not restricted by standard formats of teaching and education. Open and naturally linked towards neurosciences, INR has become a unique source of novel ideas for research, development and progress allowing new and improved approaches to challenging pathologies resulting in better anatomo-clinical results. Opening INR to Neurosciences is the best way to keep it alive and growing. Anchored in Neuroradiology, at the crossroad of neurosciences, INR will further participate to progress and innovation as it has often been in the past.

[Carotid MRI of initial and recurrent plaques in patients with restenosis after endarterectomy: three case reports].

Restenosis after carotid endarterectomy (CEA) is one of most significant complications. There is no previous report about MRI findings of restenotic lesions and preoperative plaques. The purpose of this study was to evaluate the initial and recurrent plaques in patients with restenosis after CEA by using black-blood MRI (BB-MRI). Three patients who underwent carotid artery stenting for restenosis after CEA were included in this study. The relative signal intensities (rSI) of the initial and recurrent plaques were calculated with reference to the sternocleidomastoid muscle on T1-weighted images (T1WI) and the submandibular gland on T2-weighted images (T2WI). This study investigated the rSI characteristics and morphology of the initial and recurrent plaques. All patients had restenosis within 1 year after CEA. The rSI values of the preoperative lesion were not high on T1WI and were high on T2WI in all cases (T1WI/T2WI: 0.63/2.43 in Case 1, 1.00/1.29 in Case 2, and 1.13/1.70 in Case 3). The morphology of the initial plaques was eccentric in 2 cases and concentric in 1 case. The rSI values of restenosis were high on T2WI in all cases (T1WI/T2WI: 1.09/1.20 in Case 1, 1.31/1.50 in Case 2, and 1.23/1.70 in Case 3). The morphology of restenotic lesions was concentric in all cases. The high rSI on T2WI and concentricity of the restenosis after CEA suggest early restenosis (intimal hyperplasia). The low-iso rSI on T1WI and high rSI on T2WI of the preoperative plaques are associated with restenosis after CEA. BB-MRI may be useful to evaluate and predict restenosis after CEA. (Received: May 7, 2012, Accepted: September 10, 2012).

Stroke outcomes of Japanese patients with major cerebral artery occlusion in the post-alteplase, pre-MERCI era.

This study examined outcomes of patients with acute ischemic stroke (AIS) with major cerebral artery occlusion after the approval of intravenous recombinant tissue-type plasminogen activator (IV rt-PA) but before approval of the MERCI retriever. We retrospectively enrolled 1170 consecutive patients with AIS and major cerebral artery occlusion (496 women; mean age, 73.9 ± 12.3 years) who were admitted within 24 hours after the onset of symptoms to 12 Japanese stroke centers between October 2005 and June 2009. Cardioembolism was a leading cause of AIS in this group (68.2%). The occlusion sites of the major cerebral arteries included the common carotid artery and internal carotid artery (ICA; 29.6%), middle cerebral artery (52.2%), and basilar artery (7.6%). Recanalization therapy (RT) was performed in 32.0% of patients (IV rt-PA, 20.0%; neuroendovascular therapy, 9.4%; combined, 2.5%). Symptomatic intracerebral hemorrhage within 36 hours with a ≥ 1-point increase in the National Institutes of Health Stroke Scale score occurred in 5.3% of the patients. At 3 months (or at hospital discharge), 29.3% of the patients had a favorable outcome (based on a modified Rankin scale score of 0-2), 23.8% were bedridden, and 15.6% died. After multivariate adjustment, RT was positively associated with a favorable outcome and negatively associated with death, whereas age, baseline National Institutes of Health Stroke Scale score, and ICA occlusion were negatively associated with a favorable outcome and positively associated with death. One-third of the patients with AIS and major cerebral artery occlusion were treated with RT, which was independently associated with favorable outcomes and death. However, 40% of the patients became bedridden or died during the post-alteplase, pre-MERCI era in Japan.

Periprocedural cilostazol treatment and restenosis after carotid artery stenting: the Retrospective Study of In-Stent Restenosis after Carotid Artery Stenting (ReSISteR-CAS).

Restenosis after carotid artery stenting (CAS) is a critical issue. Cilostazol can reduce restenosis after interventions in coronary or femoropopliteal arteries. We investigated whether periprocedural cilostazol treatment was related to the incidence of in-stent restenosis (ISR) or target vessel revascularization (TVR) after CAS. The study group comprised 553 of 580 patients who underwent CAS between April 2003 and August 2006 and were followed for 30 months after the procedure. ISR was defined as stenosis of at least 50% detected on angiography or ultrasonography. TVR was defined as revascularization of the treated carotid artery. During CAS, 207 patients (37.4%) were treated with cilostazol. Over 30 months, ISR occurred in 23 patients (4.2%), TVR occurred in 16 patients (2.9%), and either ISR or TVR occurred in 25 patients (4.5%). The incidence of ISR or TVR was significantly lower in the cilostazol-treated group than in the untreated group (1.4% vs 6.4%; log-rank P = .006). In a multivariate analysis, cilostazol treatment (hazard ratio [HR], 0.28; 95% confidence interval [CI], 0.08-0.95; P = .041) and stent diameter (HR, 0.73/1-mm increase; 95% CI, 0.54-0.99; P = .044) were independent factors for the occurrence of ISR or TVR. The incidence of a composite of events, including thromboembolism, hemorrhage, death, and TVR, tended to be lower in the cilostazol-treated group than in the untreated group (15.0% vs 19.9%; log-rank P = .17). Periprocedural cilostazol treatment was associated with lower rates of ISR and retreatment after CAS. A prospective randomized controlled trial is needed to clarify the effect of cilostazol on ISR after CAS.

Retrospective survey of endovascular treatment for ruptured intracranial aneurysm in Japan: Retrospective Endovascular Subarachnoid Aneurysm Treatment (RESAT) study.

Annual retrospective surveys of 20 to 31 medical centers performing endovascular treatment of cerebral aneurysms in Japan from 1997 to 2008 were performed to analyze technical and clinical outcomes of endovascular treatment for ruptured cerebral aneurysm. Patients treated with dome embolization using bare platinum coils within 14 days after onset were retrospectively selected, and clinical features, and technical and clinical outcomes at discharge were studied. Retrospective Endovascular Subarachnoid Aneurysm Treatment (RESAT) 1 covers patients treated from 1997, when the Guglielmi detachable coil was introduced, to 2002, just after International Subarachnoid Aneurysm Trial was reported. RESAT 2 to RESAT 7 were conducted annually between 2003 and 2008. Among 5,624 patients with ruptured aneurysms treated within 14 days after onset, 4,782 patients were treated by dome embolization using platinum detachable coils. The patients in this large retrospective survey included 35.8% aged over 70 years, 36.6% with posterior circulation aneurysms, and 29.3% with poor grades (Hunt and Kosnik grades IV and V). The proportion of patients aged over 70 years tended to increase each year from 33.4% in RESAT 1 to 39.8% in RESAT 7, and the proportion of those with posterior circulation aneurysms decreased from 44.2% in RESAT 1 to 23.8% in RESAT 7 (p<0.001). Overall technical success was obtained in 4,666 patients (97.6%), and favorable clinical outcome (good recovery and moderate disability) at discharge was obtained in 88.0% of grade I-III cases and 73.6% of grade I-V cases. Procedure-related morbidity was 2.9% and mortality was 0.8%. Despite this survey involving high proportions of aged, posterior circulation, and poor-grade patients, the technical success rate and immediate clinical results were relatively favorable. The patient prognosis and aneurysm changes must be investigated over a longer period, together with the effects of the introduction of new endovascular devices for cerebral aneurysms.