Michiya Kubo

Changes in cognitive function during the 1-year period following endarterectomy and stenting of patients with high-grade carotid artery stenosis

BackgroundIn patients with severe carotid artery stenosis, cognitive decline and changes in cognitive function before to after treatment have been noted, though the true effects of treatment in such patients remain unclear. A convenient and repeatable neuropsychological test battery is needed for such patients.MethodsIn 26 patients with severe carotid artery stenosis treated by carotid endarterectomy (CEA) and stenting (CAS), cognitive function was examined before and 1 week, 3 months, 6 months, and 1 year after treatment. RBANS and MMSE were selected as a test battery, and changes in test scores and long-term results of revascularization were evaluated.ResultsRBANS was useful and suitable for neuropsychological testing in such patients, and yielded the following results: (1) Patients before treatment had, on average, RBANS scores rated low average, with mild but relatively diffuse cognitive impairment; (2) RBANS scores were increased significantly at 3 months after CEA and CAS, and cognitive improvement was maintained over 1 year; and (3) scores were decreased temporarily at 1 week after CEA, but not after CAS.ConclusionsPatients with severe carotid artery stenosis exhibited mild decline in cognitive function, which was improved after CEA and CAS. RBANS is a suitable test battery for this type of patient.

Intracranial dural arteriovenous fistula with retrograde cortical venous drainage: use of susceptibility-weighted imaging in combination with dynamic susceptibility contrast imaging.

BACKGROUND AND PURPOSE: SWI is a new MR imaging method that maximizes sensitivity to magnetic susceptibility effects with phase information for visualizing small cerebral veins. The purpose of this study was to report the use of SWI in combination with DSC in examining related RCVD in patients with intracranial DAVFs. MATERIALS AND METHODS: Ten patients with angiographically confirmed DAVFs with RCVD underwent conventional MR imaging, SWI, and DSC. The ability of SWI to depict dilated cerebral veins was evaluated and then compared with DSC. The hemispheres of patients with DAVFs were grouped into affected (with RCVD) or nonaffected (without RCVD) categories by angiography. Four patients had bilaterally affected hemispheres. A total of 14 affected hemispheres in patients with DAVFs with RCVD were evaluated. RESULTS: SWI showed dilated cerebral veins on the surface of the brain in all (100%) of the 14 affected hemispheres in patients with DAVFs with RCVD and deep in the brain in 9 (64%). T2-weighted imaging showed prominent flow-voids on the surface of the brain in 10 (71%) of the 14 affected hemispheres in patients with DAVFs with RCVD and deep in the brain in 5 (36%). DSC showed increased cerebral blood volume in all of the 14 affected hemispheres. The SWI findings regarding dilated veins on the surface of the brain corresponded well with the areas of increased cerebral blood volume. CONCLUSIONS: SWI in combination with DSC could be used to characterize the presence of RCVD in patients with DAVFs.

Basic training model for supermicrosurgery: a novel practice card model.

Supermicrosurgery has been developed and reported the anastomosis of vessels with diameters of about 0.5 mm or less. The anastomosis of vessels of about 0.5 mm or less in diameter is technically more difficult than 1.0 mm or larger. This article describes a novel practice card model for acquiring basic supermicrosurgical techniques. A practice card is composed of very small-caliber silicone tubes simulating very small-caliber vessels and a thick paper. The silicone tube external diameters are 0.3, 0.5, or 0.7 mm. The thickness of the tube wall is 0.05 mm. Microsurgeons can easily begin to practice and warm up the supermicrosurgical suturing and anastomosing techniques using this nonvital practice card under a personal desk stereomicroscope in the office and an operating microscope in the operating room. This training model is a simple system for practicing basic supermicrosurgical techniques repeatedly and for warming up before a supermicrosurgical operation. This article also describes basic training regarding its use at high magnifications. This training-based supermicrosurgical skill may become a valuable technique for microsurgeons in many specialties.

Dural arteriovenous fistula involving the transverse sigmoid sinus after treatment: assessment with magnetic resonance digital subtraction angiography

IntroductionThe purpose of this study was to evaluate the utility of magnetic resonance digital subtraction angiography (MRDSA) in showing the presence or absence of retrograde venous drainage (RVD) in patients with intracranial dural arteriovenous fistula (DAVF) involving the transverse sigmoid sinus (TSS) after treatment.MethodsOf 16 patients with DAVF involving the TSS, 13 underwent digital subtraction angiography (DSA) and MRDSA before and after treatment, and 3 underwent DSA before treatment and DSA and MRDSA after treatment. Five patients underwent these procedures twice after treatment. A total of 21 examinations after treatment were evaluated retrospectively. The presence or absence of DAVF and RVD was decided on the basis of the DSA findings. Two neuroradiologists reviewed the MRDSA findings concerning the presence or absence of DAVF and RVD.ResultsDSA showed residual DAVF in 9 and residual RVD in 5 of 21 examinations. MRDSA revealed residual DAVF in 8 of 21 examinations. MRDSA did not show residual DAVF in one examination because of a very small (low-flow) residual DAVF without RVD. MRDSA identified residual RVD in 5 of 21 examinations. MRDSA was completely consistent with DSA concerning the presence or absence of residual RVD.ConclusionMRDSA could evaluate the presence or absence of RVD in patients with DAVF involving TSS after treatment. MRDSA may give reliable information as to whether patients with DAVF involving the TSS should undergo additional DSA after treatment.

Mobilization of Pluripotent Multilineage-Differentiating Stress-Enduring Cells in Ischemic Stroke

GOAL This prospective study was aimed to prove the hypothesis that multilineage-differentiating stress-enduring (Muse) cells are mobilized from bone marrow into peripheral blood in patients with ischemic stroke. MATERIALS AND METHODS This study included 29 patients with ischemic stroke. To quantify the circulating Muse cells, peripheral blood was obtained from all patients on admission and at days 7 and 30. Using fluorescence-activated cell sorting, Muse cells were identified as stage-specific embryonic antigen-3-positive cells. The control values were obtained from 5 healthy volunteers. Separately, immunohistochemistry was performed to evaluate the distribution of Muse cells in the bone marrow of 8 autopsy cases. FINDINGS The number of Muse cells robustly increased within 24 hours after the onset, compared with the controls, but their baseline number and temporal profile widely varied among patients. No clinical data predicted the baseline number of Muse cells at the onset. Multivariate analysis revealed that smoking and alcohol intake significantly affect the increase in circulating Muse cells. The odds ratio was .0027 (P = .0336) and 1688 (P = .0220) for smoking and alcohol intake, respectively. The percentage of Muse cells in the bone marrow was .20% ± .17%. CONCLUSION This study shows that pluripotent Muse cells are mobilized from the bone marrow into peripheral blood in the acute stage of ischemic stroke. Smoking and alcohol intake significantly affect their temporal profile. Therapeutic interventions that increase endogenous Muse cells or exogenous administration of Muse cells may improve functional outcome after ischemic stroke.

Hemodynamic status and treatment of aggressive dural arteriovenous fistulas

In this study the hemodynamic status and treatment modality of aggressive dural arteriovenous fistulas (dAVFs) was evaluated. Of 145 intracranial dAVFs treated in our clinic, there were 38 aggressive lesions presenting with hemorrhage, infarction, seizures, and symptoms of increased intracranial pressure. They included 3 (5% of all cavernous sinus lesions) cavernous sinus, 24 (44%) transverse-sigmoid and superior sagittal sinus, and 11 (46%) direct cortical types of dAVFs. Of these 38 aggressive lesions, retrograde leptomeningeal venous drainage was disclosed in 35 lesions, and retrograde sinus drainage in 3. Eighteen cases were treated only with endovascular procedures, 7 with surgical interventions, and 13 with combined endovascular and surgical procedures. Angiographic results were complete obliteration in 66% of the cases, subtotal and partial obliteration in 34%. Clinical outcome was GR (good recovery) in 58% of cases, MD (moderate disability) in 18%, SD (severe disability) in 13%, VS (vegetative state) in 8%, and D (death) (due to acute cardiac infarction) in 3%. Symptomatic procedural complication occurred in 3 cases. In conclusion, aggressive dural AVF resulted from retrograde leptomeningeal venous drainage. Combined surgical and endovascular treatment played the leading part in the management of this aggressive type of lesion.

Flow-sensitive alternating inversion recovery (fair) imaging for retrograde cortical venous drainage related to intracranial dural arteriovenous fistula

IntroductionTo evaluate the hypothesis that flow-sensitive alternating inversion recovery (FAIR) magnetic resonance (MR) imaging can detect retrograde cortical venous drainage (RCVD) in patients with intracranial dural arteriovenous fistula (DAVF).MethodsSeven patients with angiographically confirmed DAVF with RCVD and two DAVF patients without RCVD underwent examinations with conventional MR imaging and FAIR, five of these seven patients with RCVD also underwent examination with dynamic susceptibility contrast (DSC) MR imaging. The ability of FAIR to depict prominent cerebral veins was evaluated, and FAIR was compared with the relative cerebral blood volume (rCBV) maps created with DSC.ResultsIn all DAVF patients with RCVD, FAIR clearly showed prominent veins on the surface of the brain in affected hemisphere, and FAIR corresponded well with the areas of increased rCBV. In all DAVF patients without RCVD, FAIR showed no prominent veins.ConclusionFAIR can detect RCVD in patients with DAVF.

Warning headache of subarachnoid hemorrhage and infarction due to vertebrobasilar artery dissection.

Objectives:The authors describe the clinical features of headache in patients with vertebrobasilar artery dissection (VBAD) and emphasize the importance of recognition of warning headaches preceding subarachnoid hemorrhage. Headache in VBAD is already recognized, but the natural history and clinical features of the warning headache have not been well elucidated. Methods:The clinical features of 30 patients with VBAD were analyzed retrospectively. Results:Of the 30 VBAD patients, 16 presented with subarachnoid hemorrhage and 14 with ischemia. Headache (without any other symptoms or signs) was detected in 70% of patients with subarachnoid hemorrhage and 50% of patients with infarction. The headache started acutely, was localized to the occiput or nape of the neck, was sharp and severe in intensity, and was different from any previously experienced headaches. The interval from onset of headache to diagnosis of subarachnoid hemorrhage or infarction was 1 to 10 days. Three patients had sudden severe warning headaches without any evidence of subarachnoid hemorrhage at initial presentation and de-teriorated within 24 hours due to subarachnoid hemorrhage, demonstrated later on computed tomography. Angiographic findings of patients with warning headaches were nonspecific compared with those of patients without headache. Conclusions:The present study confirms a high frequency of headache in patients with VBAD. Sudden severe occipital and nuchal pain, even without subarachnoid hemorrhage or any neurologic deficit, should be considered as a warning sign of subarachnoid hemorrhage. Computed tomography, magnetic resonance imaging, and magnetic resonance angiography should be performed urgently for screening of patients with a warning headache to prevent resultant life-threatening major vascular events.

Chlamydia pneumoniae infection is not involved in carotid artery stenosis

Recent studies have suggested the existence of a close relationship between Chlamydia pneumoniae infection and atherosclerosis. However, it has been speculated that C. pneumoniae infection is not associated with early atherosclerosis but with advanced atherosclerosis. In the present study, we test this hypothesis. In 524 consecutive patients who underwent cerebral angiography were recruited for the study. From the films obtained during angiography, percent stenosis of neck internal carotid artery was calculated according to the method of the North American Symptomatic Carotid Endarterectomy Trial (NASCET). Serum C. pneumoniae IgG and IgA antibodies were measured by a commercial ELISA enzyme immunoassay kit. Cerebrovascular risk factors such as age, gender, hypertension, diabetes mellitus, hyperlipidemis and smoking were assessed by interview. Old age above 60 years and diabetes mellitus were found to be independent risk factors for carotid artery stenosis in this study after adjustment for cerebrovascular risk factors. When we defined carotid artery stenosis as the presence of greater than 30% stenosis of one artery, there was no association after adjustment for other risk factors between C. pneumoniae IgG and IgA seropositivity and the presence of carotid artery stenosis for any cut-off value of seropositivity. When we defined carotid artery stenosis as the presence of greater than 70%, there was also no association between C. pneumoniae IgG and IgA seropositivity and the presence of carotid artery stenosis for any cut-off value of seropositivity. These results suggest that C. pneumoniae infection is not associated with carotid artery atherosclerosis.

The Impact of Cavernous Sinus Drainage Pattern on the Results of Venous Sampling in Patients With Suspected Cushing Syndrome

BACKGROUND AND PURPOSE: Selective venous sampling from the posterior portion of the cavernous sinus (CS) is recommended for the diagnosis of Cushing disease, because samples from the posterior portion yield higher adrenocorticotropic hormone (ACTH) levels than those from the anterior and middle portions. We prospectively assessed this intracavernous gradient of ACTH level to determine which site in the CS yields adequate sampling. MATERIALS AND METHODS: In 5 patients with Cushing syndrome, cavernous sinography was performed to assess drainage pattern of the CS. Sampling was performed from the anterior, middle, and posterior parts of the CS, inferior petrosal sinus (IPS), and the peripheral vein. The ratio of the concentration in CS and IPS to that in peripheral blood plasma (C/P ratio) was calculated. RESULTS: Cavernous sinography showed that the main drainage route was the IPS in 6 sides and that the pterygoid plexus (PP) was developed to the same extent as the IPS in 3 sides. In 1 patient, the CS drained mainly to the PP. In 1 patient with an ectopic lesion, no increase in ACTH level was detected. In 3 of 4 patients with Cushing disease, the highest C/P ratio was obtained from the posterior portion. In 1 patient whose main drainage route was the PP, the highest C/P ratio was obtained from the anterior portion. In this case, sampling data from the posterior portion and the IPS yielded false-negative results. CONCLUSION: Understanding the drainage patterns of the CS is essential for interpretation of sampling data from the CS and avoiding false-negative results.