A Novel Technique to Retrieve a Snagged Stent Retriever: Technical Note.

Objective: Currently, there are no established approaches for removal of devices, such as stents, which sometimes become difficult to recover during endovascular treatment. We report a new method to successfully remove a stent that has become snagged during thrombus removal. Case Presentation: An 82-year-old female who had undergone a mitral valve annuloplasty developed sudden aphasia, right hemiplegia, and right unilateral spatial neglect on postoperative day 10. Cranial MRI indicated occlusion of the horizontal segment of the left middle cerebral artery. During mechanical thrombectomy, a vasospasm snagged the stent, and re-sheathing attempts failed repeatedly. We wedged the microcatheter into the spasm site and slowly injected a solution containing 1 cc of nicardipine, 2 cc of contrast medium, and 2 cc of heparin in normal saline intra-arterially. After several minutes, we retracted the Trevo wire slightly and easily removed the stent. The thrombus adhered to the retrieved stent. Post-retrieval imaging showed that the branch was completely recanalized. Conclusion: In cases wherein a microwire or stent retriever becomes difficult to remove, we propose switching to a microcatheter with a sufficient diameter to allow vasodilator injection. If the microcatheter is difficult to remove, our method can be utilized by severing the hub, inserting a larger-bore catheter, and injecting vasodilators. Adding contrast medium to the intra-arterial injectate allows visualization of whether the solution has reached the spasm site. Furthermore, by injecting the solution through the wedged catheter, pooling of the solution at the spasm site can be confirmed.

[Clipping of a Large Unruptured Basilar Artery Trunk Large Aneurysm Using Rapid Ventricular Pacing:A Case Report].

Neck clipping of basilar trunk aneurysms, particularly those of a large size, is challenging because of its location. Here, we report a case of a basilar artery aneurysm successfully treated with neck clipping using rapid ventricular pacing(RVP). A 67-year-old woman was referred to our hospital for treatment of a large basilar artery aneurysm. Although coiling was considered, we performed neck clipping of this aneurysm because of the expected radical therapeutic effect. The patient was positioned in the right park-bench position, and right suboccipital craniotomy was performed. The aneurysm was mainly approached via the right supracerebellar route. RVP softened the aneurysm for easy dissection and insertion of multiple clips. The postoperative course was uneventful, and she was discharged 1 week later without neurological deficits. RVP should be considered for the treatment of complex aneurysms as adjunctive techniques.

[Relationship of Distal Anterior Cerebral Artery Aneurysm Arising from the Supracallosal Portion and Accessory Anterior Cerebral Artery].

Median artery of the corpus callosum(MACC)refers to the median artery of the triplicate anterior cerebral artery(ACA). When MACC distributes to one or to both hemispheres, it is known as the accessory ACA. We performed detailed angiographic analysis of 32 consecutive patients operated upon for distal ACA(DACA)aneurysms, and noted that all DACA aneurysms occurring in the supracallosal portion were accompanied by an accessory ACA as vascular malformation. Such relationship between accessory ACA and DACA aneurysm in the supracallosal portion has not been previously reported.

Gradually Progressive Symptoms of Normal Pressure Hydrocephalus Caused by an Arachnoid Cyst in the Fourth Ventricle: a Case Report.

BACKGROUND: Arachnoid cysts in the fourth ventricle are extremely rare, with only 13 cases having been described in the literature. Especially, only 1 case of a patient older than 70 years has been reported. Arachnoid cysts in the fourth ventricle may cause obstructive hydrocephalus. Here, we report the case of a 72-year-old man who presented with an arachnoid cyst in the fourth ventricle that caused gradually progressive symptoms of normal pressure hydrocephalus. METHODS: A 72-year-old man complaining of persistent dizziness and gait difficulty was admitted to our hospital due to a gradual worsening of his symptoms and apparent cognitive impairment. Computed tomography scan of the head showed symmetrically dilated third, fourth, and lateral ventricles. RESULT: Though we performed a ventriculoperitoneal shunt operation, his trunk ataxia persisted. We finally diagnosed an arachnoid cyst in the fourth ventricle by direct ventricular infusion of enhanced material. We performed direct surgical fenestration of the cyst and achieved a good outcome. CONCLUSION: Arachnoid cysts of the fourth ventricle are exceedingly rare, but it is important to recognize them because they cause normal pressure hydrocephalus symptoms and cerebellar or brainstem deficit. We propose detailed neurologic and radiologic examinations of patients with normal pressure hydrocephalus symptoms to avoid unnecessary shunt.

Significance of urinary glucaric acid measurement and its application to paclitaxel therapy.

Individual variations in P-450 activity affect the in vivo pharmacokinetics as well as the efficacy and side effect of drugs. It is proposed that urinary glucaric acid (GA) level may indirectly represent P-450 activity and may therefore be an indicator of P- 450 activity in the clinical setting. However, no standard method has been developed so far. Metabolism of paclitaxel (PTX), an anticancer drug, is mediated by P-450. If P-450 activity could be predicted by measuring urinary GA level during PTX administration and individual blood PTX concentration could be inferred, urinary GA level would be a potent tool to predict the efficacy and side effects of the drug. We therefore measured the urinary GA levels of patients on antiepileptics that are suggested to induce P-450 and those of control subjects, to determine whether urinary GA level could be an indicator of P-450 activity. Then, we examined the relationship between urinary GA level and blood PTX concentration and looked into the possibility of predicting pharmacokinetics based on the relationship between urinary GA level and area under the blood concentration-time curve (AUC). The means+/-S. D. of urinary [(GA level)/(Cr level) x 10] levels of 16 patients on antiepileptic medication and 24 control subjects were 0. 98 mg/mL+/-0. 91 and 0. 19 mg/mL+/-0. 07, respectively. The urinary GA levels of patients on antiepileptic medication were significantly higher than those of control subjects. On the other hand, the relationship between AUC and urinary GA levels in eight patients on PTX showed that AUC tended to become large when urinary GA levels were low. The above results reveal that measuring urinary GA level by the easy and noninvasive way of urine collection would enable us to predict P-450 activity and infer blood PTX concentration.

A case of granuloma in the occipital lobe of a patient with Wegener's granulomatosis.

We report a case of Wegener's granulomatosis (WG) with central nervous system (CNS) involvement in a woman who complained of bilateral visual disturbance. The intracranial necrotizing granulomatous lesion was confirmed by MR imaging and brain biopsy. After high-dose oral corticosteroid treatment, not only clinical manifestations but also laboratory tests improved. Moreover, the CNS lesion completely regressed. This suggests that high-dose corticosteroid alone might be effective in treating WG with CNS involvement.

Basilar trunk aneurysms with associated fenestration treated by using Guglielmi detachable coils: two cases reports.

Basilar trunk saccular aneurysms associated with fenestration are infrequent. Surgical treatment of a basilar trunk aneurysm is difficult because of its anatomic environment and complicated surgical exposure. We experienced two cases of basilar fenestration aneurysm, and the patients were treated using Guglielmi detachable coils. The usefulness of 3-dimensional digital subtraction angiography and efficacy of endovascular treatment for basilar trunk aneurysms with associated fenestration is discussed in this article, and the relevant literature is reviewed.

Expression of ciliary neurotrophic factor (CNTF), CNTF receptor alpha (CNTFR-alpha) following experimental intracerebral hemorrhage in rats.

Ciliary neurotrophic factor (CNTF) is known as a neuro-survival factor in the developing and developed CNS, as well as in the CNS following injury. However, little is known about the expression of CNTF or that of its receptor (CNTFR-alpha) in cases of intracerebral hemorrhage (ICH). We investigated the temporal and spatial profiles of CNTF and CNTFR-alpha expression using a collagenase-induced ICH rat model. CNTF expression was up-regulated from the day following ICH induction and reached a peak level at 5 to 14 days, with increased expression observed in brain tissue surrounding the hematoma lesion and white matter structures in association with astroglial proliferation. Further, CNTFR-alpha was transiently expressed in the cerebral cortex surrounding the hematoma, with a peak at 5 days. Administration of exogenous CNTF into the lesion following initiation of ICH resulted in a prolonged expression of CNTFR-alpha on cortical neurons neighboring the hematoma. Our findings suggest differential regulation of CNTF and CNTFR-alpha, and the possibility of a therapeutic strategy using CNTF administration for ICH.

Brain metastases from urachal carcinoma.

We present a case of brain metastases of the urachal carcinoma, which is extremely rare and malignant. Contrast-enhanced MRI was employed to detect them. A large mass was removed surgically and 4 other small metastases were treated by gamma knife radiosurgery. Six weeks after radiosurgery, the 4 lesions had disappeared on MRI. We emphasise the importance of early diagnosis using MRI and treatment by radiosurgery for this rare condition.

[Vascular endothelial growth factor expression in the rat dural arteriovenous fistula model].

UNLABELLED: Although various mechanisms of the development of dural arteriovenous fistula (DAVF) have been proposed, the pathogenesis of these lesions are still unclear. Recent experimental evidence suggested a role of angiogenic growth factors in the genesis of vascular malformations of the central nervous system. To further investigate the pathogenesis of DAVF, we examined the expression of the angiogenic growth factor, vascular endothelial growth factor (VEGF), in rat DAVF model. MATERIAL AND METHODS: Male Wistar rats (weighting 280 to 300 g, n = 40) were used. Each rat was mounted on a stereotaxic frame under general anesthesia. DAVF model (Spetzler et al.) was made by common carotid artery-external jugular vein anastomosis, bipolar coagulation of the vein draining the transverse sinus, and superior sagittal sinus thrombosis (SSS). SSS was thrombosed by a hemostatic agent through 16-gauge needle. Venous hypertension was induced in 30 rats, which were divided into two experimental groups; (1) immunohistological study group (n = 15) and (2) angiography group (n = 15). Immunohistological analysis was performed by VEGF antibody 1 week after, and angiography was done 90 days after the surgery. Developing of angiographical DAVF was observed with the magnifying X-ray camera. Each 5 rats served as sham-operated controls, which received a similar surgery without induction of venous hypertension. RESULTS: VEGF expression and DAVF were not observed in sham group. In immunohistological study group, VEGF expression in the endothelium and the connective tissues of the dura mater in the five rats (33%) and in the neurons in the eleven rats (73%) of the cerebral cortex and the basal ganglia were identified. In angiography group, DAVF formed in 6 among 15 rats (40%). CONCLUSION: The findings of this study provide the first experimental evidence that angiogenic growth factors VEGF may participate in the genesis of DAVF. These results suggest a novel strategy for the management and prevention of DAVF and related disorders.

Color Doppler flow imaging of the superior ophthalmic vein in dural arteriovenous fistulas.

BACKGROUND AND PURPOSE: This article evaluates the intracranial venous hemodynamics of dural arteriovenous fistula (DAVF) on the basis of data from color Doppler flow imaging (CDFI) findings of the superior ophthalmic vein (SOV) and discusses the clinical application of the SOV CDFI to the DAVFs. METHODS: We examined the diameter, flow direction, flow waveform, and flow velocity of the SOV using CDFI in 20 patients with intracranial DAVF. Six patients were asymptomatic; the other 14 patients were symptomatic. Angiographic retrograde cortical venous filling was seen in 14 patients. RESULTS: In the DAVFs, the average SOV diameter was 2.95+/-1.15 mm, which was significantly broad compared with that of the control subjects (P<0.05). The flow direction was reversed in 2 patients and normal in the other 18 patients. Three patients showed an abnormal waveform. A reversed pulsatile waveform was observed in 2 patients, and a normograde pulsatile waveform was seen in 1 patient. The other 17 patients showed normal waveform. The average SOV diameter and resistance index values were significantly higher (P<0.05) in patients with clinical symptoms, angiographic retrograde cortical venous fillings, or large DAVFs compared with those in the other patients. CONCLUSIONS: The SOV CDFI findings in DAVFs correlated well with the patient's clinical symptoms, angiographic findings, and DAVF size. These findings were useful to evaluate the intracranial venous hemodynamics in DAVFs.

Further study of CD31 protein and messenger ribonucleic acid expression in human cerebral vascular malformations.

OBJECTIVE: In a previous study, we documented lower levels of immunoexpression of platelet endothelial cell (EC) adhesion molecule (CD31) in paraffin sections of cerebral cavernous malformations (CCMs), compared with arteriovenous malformations (AVMs) or normal brain tissue. We hypothesized that down-regulation of CD31 in CCMs might represent a distinctive phenotypic feature of ECs in this disease. To confirm this hypothesis, we further examined both protein and messenger ribonucleic acid (mRNA) expression of CD31, using immunohistochemical and in situ hybridization analyses, in fresh-frozen specimens of CCMs, AVMs, and control brain tissue. METHODS: Fresh-frozen sections of four AVMs, five CCMs, and four control brain tissue specimens obtained from surgical resections were immunohistochemically stained with antibodies to von Willebrand factor and two distinct epitopes of CD31. In two AVMs, four CCMs, and three control brain tissue samples from the aforementioned group, the expression of CD31 mRNA was also examined by using in situ hybridization. Large (>100-microm) and small (<100-microm) vessels were counted and assessed for protein and mRNA expression. RESULTS: In all tissues, ECs in the majority of vessels were immunopositive for CD31 with two distinct antibodies. CD31 mRNA was expressed in some but not all vessels in AVMs, CCMs, and control brain tissue. There were no statistically significant differences in CD31 protein or mRNA expression in CCMs, AVMs, and control brain tissue. CONCLUSION: The expression of CD31 in CCMs can be underestimated in paraffin sections. There does not seem to be a unique phenotypic differentiation of CD31 expression in ECs of CCMs or AVMs, compared with control brain tissue.