Dae Chul Suh

The VITATOPS (Vitamins to Prevent Stroke) Trial: Rationale and Design of an International, Large, Simple, Randomised Trial of Homocysteine-Lowering Multivitamin Therapy in Patients with Recent Transient Ischaemic Attack or Stroke

Background: Epidemiological studies suggest that raised plasma concentrations of total homocysteine (tHcy) may be a common, causal and treatable risk factor for atherothromboembolic ischaemic stroke. Although tHcy can be lowered effectively with small doses of folic acid, vitamin B12 and vitamin B6, it is not known whether lowering tHcy, by means of multivitamin therapy, can prevent stroke and other major atherothromboembolic vascular events. Purpose: To determine whether vitamin supplements (folic acid 2 mg, B6 25 mg, B12 500 µg) reduce the risk of stroke, and other serious vascular events, in patients with recent stroke or transient ischaemic attacks of the brain or eye (TIA). Methods: An international, multi-centre, randomised, double-blind, placebo-controlled clinical trial. Results: As of November 2001, more than 1,400 patients have been randomised from 10 countries in four continents. Conclusion: VITATOPS aims to recruit and follow up 8,000 patients between 2000 and 2004, and provide a reliable estimate of the safety and effectiveness of dietary supplementation with folic acid, vitamin B12, and vitamin B6 in reducing recurrent serious vascular events among a wide range of patients with TIA and stroke.

Spectrum of lateral medullary syndrome. Correlation between clinical findings and magnetic resonance imaging in 33 subjects.

Background and Purpose Computed tomography is insufficient in evaluation of medullary lesions. Although lateral medullary infarction is a relatively common type of cerebrovascular disease, detailed correlation between clinical findings and magnetic resonance imaging (MRI) has not yet been reported. Methods We studied 33 consecutive patients with lateral medullary infarction who showed appropriate MRI lesions and correlated their clinical findings with the MRI results. Results Gait ataxia (88%), vertigo/dizziness (91%), nausea/vomiting (73%), dysphagia (61%), hoarseness (55%), Horner sign (73%), and facial (85%) and hemibody (94%) sensory changes were frequent clinical findings. MRI results showed that the lesions located in the rostral part of the medulla were usually diagonal band‐shaped and were associated with more severe dysphagia, hoarseness, and the presence of facial paresis, whereas the caudal lesions, situated usually in the lateral surface of the medulla, appeared to correlate with more marked vertigo, nystagmus, and gait ataxia. Nausea/vomiting and Horner sign were common regardless of the lesion location, and lesions extending ventromedially correlated with facial sensory change on the contralateral side of the lesion. Conclusions Analysis of MRI findings in rostrocaudal and dorsoventral aspects allows us, although not unequivocally, to make anatomicoclinical correlations in the evaluation of patients with lateral medullary stroke syndrome. (Stroke. 1994;25:1405‐1410.)

Intracranial Dural Arteriovenous Fistulas: Analysis of 60 Patients

Objective: To analyze and update the clinical symptomatology, CT and MRI findings, angiographic features, and therapeutic outcomes of patients with dural arteriovenous fistulas (DAVFs). Background: Studies of DAVFs in a large number of patients have seldom appeared in neurology literature. Methods: The authors investigated 60 consecutive patients with DAVFs who were admitted between January 1991 and January 2001. The DAVFs were graded into five types according to the classification of Cognard et al. [Radiology 1995;194:671–680]. Presumable etiologies, clinical features, imaging findings and therapeutic outcomes were evaluated on the basis of the location and type of DAVFs. Results: Sinus thrombosis, previous trauma, craniotomy, cerebral infarction and acupuncture were detected as possible etiologic factors of DAVFs. The cavernous sinus (57%) was the most common location of DAVFs. Although the neurological symptoms were closely related to the location of the DAVFs, in some patients, there were also symptoms that did not reflect the location. Although the women outnumbered the men, the men presented with aggressive neurological manifestations more often (p < 0.05). Ten out of 12 patients (83%) with DAVFs involving locations other than the large sinuses presented with aggressive neurological manifestations. 70% of brain CTs and 81% of brain MRIs showed abnormal findings suggestive of DAVFs. Of 33 patients who underwent only endovascular embolization, 29 patients (88%) were cured or improved. Radiosurgery and surgical excision done in some patients provided fair results. Patients with DAVFs involving large sinuses showed a better therapeutic outcome than those in whom locations other than the large sinuses were involved, while patients without venous ectasia had more a favorable outcome than those with it (each, p < 0.01). Conclusions: DAVFs result from various etiologic factors, show diverse manifestations usually reflecting the location and can be treated successfully in most patients. Factors related to poor clinical outcome include male sex, the presence of venous ectasia and involved locations other than the large sinuses.

Intracranial Stenting of Severe Symptomatic Intracranial Stenosis: Results of 100 Consecutive Patients

BACKGROUND AND PURPOSE: There are a few reports regarding the outcome evaluation of balloon-expandable intracranial stent placement (BEICS). The purpose of our study was to evaluate the outcome and factors related to the adverse events (AEs) of BEICS. MATERIALS AND METHODS: We evaluated 100 consecutive patients who underwent BEICS. We assessed the procedural success (residual stenosis <50%), AEs (minor strokes, major strokes, and death), clinical outcome, and restenosis (>50%) at 6 months. We also analyzed 18 factors including symptom patterns related to AE rate. Symptom patterns revealed 1) stable patients (n = 73) with improving, stationary, or resolved symptoms; and 2) unstable patients (n = 27) with gradual worsening or fluctuating symptoms (National Institutes of Health Stroke Scale [NIHSS] ≥4) within 2 days before stent placement. RESULTS: The procedural success rate was 99%. Overall, there were 10 (10%) AEs within the 6 months: 4 (4%) minor strokes, 3 (3%) major strokes, and 3 (3%) deaths including a death from myocardial infarction. AE rate was 4.1% in stable and 25.9% in unstable patients. Restenosis at 6 months revealed 0% (0/59). Good outcome (modified Rankin Scale ≤2) at 6 months was 97% (71/73) in stable and 67% (18/27) in unstable patients. Stepwise logistic regression model revealed that symptom pattern (unstable versus stable) was the only significant risk factor (OR, 8.167; 95% CI, 1.933–34.500; P = .004). CONCLUSION: BEICS revealed a low AE and good outcome rate at 6 months, especially in the stable patients. Midterm outcome was also favorable in the unstable patient group.

Safety and efficacy of MRI-based thrombolysis in unclear-onset stroke. A preliminary report

Background: Standard selection criteria for thrombolysis typically exclude patients with acute ischemic stroke with unclear onset. Multimodal MRI screening may be able to identify those with a favorable benefit-risk ratio for thrombolysis. We aimed to evaluate the safety and efficacy of MRI-based thrombolysis in unclear-onset stroke (UnCLOS). Methods: We reviewed the thrombolysis database registries from 3 medical centers in Korea. Subjects received thrombolysis with intravenous tissue plasminogen activator (tPA) or combined intravenous tPA and intra-arterial urokinase within 3 h, or intra-arterial urokinase within 6 h from symptom detection. For patients with UnCLOS, MRI-specific eligibility criteria (i.e. positive perfusion-diffusion mismatch and absence of well-developed fluid-attenuated inversion recovery changes of acute diffusion lesions) were applied. Rates of immediate and 5-day recanalization, early neurological improvement and symptomatic intracranial hemorrhage (ICH) within 48 h after treatment and 3-month modified Rankin Scale (mRS) scores were compared between patients with UnCLOS and those with clear-onset stroke (CLOS). Results: 32 patients with UnCLOS and 223 patients with CLOS were included. Baseline characteristics were comparable between the two groups, except that the proportion of MRI screening was higher, and detection-to-door time and door-to-needle time were longer in the UnCLOS group (p < 0.01). Rates of recanalization (immediate, 81.3 vs. 63.1%; delayed, 80.6 vs. 69.1%), early neurological improvement (on day 1, 46.9 vs. 35.9%; on day 7, 50.0 vs. 49.3%), symptomatic ICH (6.3 vs. 5.8%) and 3-month outcome (mRS 0–1, 37.5 vs. 35.0%; mRS 0–2, 50.0 vs. 49.3%) did not differ between the UnCLOS and CLOS groups. Conclusion: These preliminary results suggest that thrombolysis based on MRI criteria may safely be applied to acute stroke patients with unclear onset.

New Concept in Cavernous Sinus Dural Arteriovenous Fistula Correlation With Presenting Symptom and Venous Drainage Patterns

Background and Purpose— An extradurally located cavernous sinus dural arteriovenous fistula (CSDAVF) exhibits different clinical behavior from other dural arteriovenous fistulas (DAVFs) located between 2 dural leaves. The aim of this study is to define angiographic types of CSDAVF associated with presenting symptom (Sx) and venous drainage patterns. Methods— CSDAVFs during a mean of 23-month follow-up period of 58 patients (17 to 73 years, male:female ratio=8:50) were retrospectively analyzed. The 3 types of CSDAF, ie, proliferative (PT), restrictive (RT), and late restrictive (LRT) types, were categorized by the degrees and patterns of prominent arteriovenous shunt as well as venous flow. The status of the venous connection with CS and the presenting Sx patterns classified as orbital (OrbSxP), ocular (OcuSxP), cavernous (CavSxP), and cerebral (CerSxP) were associated with angiographic types as well as symptom onset, age, and gender. Correlations of discrete and categorical variables were statistically analyzed using the &khgr;2 or Fisher exact test. Results— PT (n=23) and RT (n=23) of CSDAVF were more common than LRT (n=12) (P=0.016) in patients with younger than 65 years and were related to OrbSxP (P=0.015) and CavSxP (P=0.038) in contrast to LRT to OcuSxP (P=0.004). Early onset of Sxs was related to the OrbSxP (P=0.08) and CavSxP (P<0.001). CerSxP (5%) was noted in RT or LRT. OrbSxP was related to the superior ophthalmic venous drainage (P=0.026) and CavSxP to the inferior petrosal sinus (P=0.046) and posterior fossa venous drainages (P=0.014). Seven patients revealed chronological progression of CSDAVF from PT to LRT and even to complete healing. Conclusions— CSDAVF presents as 3 distinctive angiographic types and is associated with presenting Sxs and venous drainage patterns.

Wyburn-Mason or Bonnet-Dechaume-Blanc as Cerebrofacial Arteriovenous Metameric Syndromes (CAMS): A New Concept and a New Classification

The diagnosis of Bonnet-Dechaume-Blanc or Wyburn-Mason syndrome encompasses a spectrum of phenotypic expression. Features of the syndrome as originally described, and common to all, include arteriovenous malformations of the brain and orbit (with retinal and/or retrobulbar lesions). A portion of these patients manifest the complete expression of the disease with additional high-flow arteriovenous malformations of the maxillofacial or mandibular regions. These present the distinct and additional risks of life-threatening epistaxis or gingival haemorrhage. We suggest new diagnostic criteria for the syndrome. Applying insights from modern developmental biology to our series of 15 patients (the largest to date), together with a review of the literature, we have recognised metameric patterns of involvement in what we believe to be a disease of the neural crest or adjacent cephalic mesoderm. This allows us to propose a new rational classification reflecting the putative, underlying disorder and to suggest a new name: Cerebrofacial Arteriovenous Metameric Syndrome (CAMS).

MR Appearance of Central Neurocytoma

To provide a detailed description of the MR appearances of central neurocytoma, MR images of 13 patients with central neurocytoma were retrospectively reviewed and compared with CT examinations. The histology was confirmed by ultrastructural and immunohistochemical studies. In 12 patients the tumors were histologically benign and located in the anterior part of the lateral ventricle, 6 of which extended to the 3rd ventricle. There was one case of a histologically malignant variant involving the thalamus and lateral ventricle. The tumors were primarily solid, but contained cysts (85%, 11/13), calcifications (69%, 9/13), and signal void from tumor vessels (62%, 8/13), frequently producing heterogeneous signal intensity on both T1- and T2-weighted images. Most of the solid portion appeared isointense or slightly hyperintense relative to the cerebral cortex on all MR pulse sequences. Calcifications were iso- or hypointense on MR, making them difficult to characterize with MR alone. Intratumoral hemorrhage was seen in 2 patients on MR but not on CT. Contrast enhancement was variable in degree and pattern. Coronal and sagittal MR images were valuable in evaluating the tumor extent and origin site, and in planning the surgical approach. It is concluded that MR imaging appears to be more useful than CT in the overall evaluation of central neurocytoma, even though calcification is better characterized with CT.

Percutaneous Transluminal Angioplasty for Symptomatic Middle Cerebral Artery Stenosis: Long-Term Follow-Up

Background and Objective: Although percutaneous transluminal angioplasty (PTA) is an effective treatment modality in the coronary and peripheral arterial diseases, its efficacy for intracranial atherosclerotic stenosis has not been verified. We assessed the long-term outcome of PTA for symptomatic middle cerebral artery (MCA) stenosis. Methods: We performed PTA in 10 patients with symptomatic high-grade stenosis (>70%) on M1 segment of MCA, who had either recurrent transient ischemic attacks (TIAs) resistant to medical therapy or perfusion problems. PTA was performed with a microballoon (2–2.5 mm diameter and 10–13 mm length) without insertion of a stent. After PTA, we evaluated the possible occurrence of restenosis, which was defined as >50% stenosis on follow-up conventional angiogram or increased M1 flow velocity on follow-up transcranial doppler up to the baseline value. Results: PTA was successfully performed in 9 patients without any serious complications. One patient had asymptomatic dissection. Residual stenosis was less than 50% in diameter in all the patients. During follow-up period (mean 34.5 months), TIAs did not recur in 6 of 7 patients who had had intractable TIAs.Two patients developed strokes, which were not referable to the index MCA lesions. Among the 6 patients who underwent follow-up conventional angiography or serial TCD, restenosis was noticed in 3 patients (50%). Conclusion: Although restenosis is not uncommon, PTA for symptomatic MCA stenosis is a relatively safe procedure, and can be used to prevent recurrent TIAs or strokes in selected patients.

High resolution MRI difference between moyamoya disease and intracranial atherosclerosis

Along with intracranial atherosclerotic disease (ICAD), moyamoya disease (MMD) is the most common cause of middle cerebral artery (MCA) occlusion in Asians. Although they have differing vascular wall pathologies, conventional angiographic evaluation methods cannot easily differentiate MMD from ICAD in certain situations, such as in young patients with atherosclerotic risk factors. High resolution magnetic resonance imaging (HR‐MRI) findings for the diseased segments of MCAs in MMD and symptomatic ICAD were compared to further elucidate differences in arterial wall changes.