Naoko Fujimura

Giant aneurysm at the origin of the accessory middle cerebral artery.

BACKGROUND Aneurysms of the A1 portion of the anterior cerebral artery are rare. The accessory middle cerebral artery is also a rare anomalous artery. CASE REPORT We operated on a 53-year-old man because of a giant aneurysm which arose at the junction of the accessory middle cerebral artery and the horizontal portion of the anterior cerebral artery (A1 portion). CONCLUSION This is the first report of a giant aneurysm of that region. A detailed evaluation of the angiogram is necessary prior to the operation, in order to select the most appropriate operative method to secure the blood flow of the accessory middle cerebral artery and distal anterior cerebral artery.

Primary Intracerebral Malignant Fibrous Histiocytoma in a Child

We report herein a rare case of pediatric intracerebral malignant fibrous histiocytoma (MFH). A 2-year-old boy gradually developed mild left hemiparesis and became somnolent. Magnetic resonance imaging upon admission revealed a well-enhanced mass lesion in the right frontotemporal operculum. Subtotal removal of the tumor was successfully performed using a right transsulcal and transcortical approach. The tumor developed as an extraaxial mass with brain adhesion to the arterial wall of the branch of the middle cerebral artery rather than to cerebral tissue. Pathological examination confirmed the presence of inflammatory-type MFH. Pediatric cases of intracerebral MFH are rare, and the possible origin of the tumor is discussed based on clinicopathological findings.

Stability of microcatheter for cerebral aneurysm embolization after steam shaping.

To compare the performance of stability after steam shaping on 4 types of microcatheters, which are commonly used for cerebral aneurysm embolization, an experimental simulation was performed. Distal portion of the microcatheters were shaped into the 90 degree with length of 5 mm with the steam under the instruction of each catheter. In the temperature kept water bath, the change of the angle of the catheter tips were recorded and measured. Several stresses were added to the tips with coaxially passing through the guiding catheter, using guidewire and Guglielmi detachable coil (GDC). The degree of straightening was prominent on braided microcatheters and on the short length of shaping. The degree of recover of the primary shaping was prominent on non-braided catheter. The most influence factor of straightening of shaped catheter tip was the stress from the manipulation of guidewire. The influence from the inserting GDC was less than the guidewire manipulation. It was shown that the decreased angle after large stress was recovered under the situation of without or with small stress. Our study shows that the non-braided microcatheter was suitable when stability of microcatheter tip after steam shaping was requested for aneurysm coiling.

Subtracted vortex centers path line method with cinematic angiography for measurement of flow speed in cerebral aneurysms

Abstract Background and purpose: The assessment of blood flow speed by imaging modalities is of increasing importance for endovascular treatment, such as stent implantation, of cerebral aneurysms. The subtracted vortex centers path line method (SVC method) utilizes image post-processing for determining flow quantitatively. In current practice, intra-aneurysmal flow in an in vitro model is visualized by laser sheet translumination and digitally recorded. In this study, we applied this method to cinematic angiography (CA), which is the preferred imaging method for endovascular interventions, to analyse hemodynamic changes. The SVC method was applied to the images and compared with results of the slipstream line method with colored fluid. Methods: A transparent tubular model was constructed of silicone which included an aneurysm 10 mm in diameter and having a 5 mm neck on a straight parent artery with a diameter of 3.5 mm. The model was integrated into a pulsatile circulation system. By CA, successive images at 25 frames/s with injection of contrast were obtained. Results and conclusion: Rotating vortexes of contrast, which advanced along the wall of the aneurysm, were observed in successive images of the aneurysm cavity. This phenomenon was also observed in the successive images with the slipstream line method. The speed of the vortex center was calculated and the results show that the vortex speed of CA was the same as that under the slipstream line method. This indicates the possibility of applying the SVC method to medical imaging equipment for analysis of the flow in aneurysms containing stent.

Preoperative Embolization of Brain Tumor with Pial Artery or Dural Branch of Internal Carotid Artery as Feeding Artery

This study evaluated the clinical usefulness of preoperative embolization of the pial artery or dural branch of the internal carotid artery (ICA) for brain tumor. Subjects comprised 17 patients with large hypervascular brain tumors who underwent preoperative selective embolization. Micro-catheters (2- or 1.7-F) and shapeable hydrophilic micro-guide wires were used for pial artery (branching from the posterior or anterior cerebral artery) or ICA dural branch embolization. Embolization was performed under digital subtraction fluoroscopy with Polyvinyl alcohol (PVA) particles (150–250 mm) and/or liquid coil. Tumor resection was performed immediately or the day after embolization. Digital subtraction angiography (DSA) before and after endovascular devascularization, blood loss during tumor resection, and clinical outcome were evaluated. All endovascular procedures were technically successful. Post-embolization DSA revealed either a disappearance or a marked decrease of the tumor stain in all cases. Control of intraoperative bleeding was easily accomplished, and intraoperative blood loss was low. Preoperative particle embolization of the feeding artery from the cortical artery or ICA dural branch is safe and effective as adjuvant therapy before tumor resection.

Clinical Outcomes of Coil Embolization for Acutely Ruptured Aneurysm. Comparison with Results of Neck Clipping when Coil Embolization is Considered the First Option.

The purpose of this prospective study was to evaluate clinical results in patients with acutely ruptured cerebral aneurysm treated by neck clipping (NC) or coil embolization (CE) when CE was considered the first option. Between 1998 and 2003, 280 patients with acutely ruptured cerebral aneurysms excluding intracerebral hematoma were evaluated. Patients were managed prospectively according to the following protocol: primary treatment modality was CE (n =179). NC (n=101) was selected for the patients with aneurysms that were small (less than 2 mm) or an unsuitable shape for CE. Surgical complication rates were 4.5% for CE and 16.8% for NC. Symptomatic vasospasm occurred in 8.4% of CE patients and 29% of NC patients. Good recovery on the Glasgow Outcome Scale was achieved by 71% of CE patients and 50% of NC patients at discharge. Surgical complications and symptomatic vasospasm were significantly reduced in CE compared to NC. Clinical outcome at discharge was also better with CE. Although 18.3% of CE patients showed various degrees of aneurysmal recanalization and 7% of CE patients required additional treatment (re-CE or NC), aneurysmal rebleeding occurred in only one patient during follow-up (mean, 3.95 years).

Method to quantify flow reduction in aneurysmal cavities of lateral wall aneurysms produced by stent implants used for flow diversion.

Stent implants placed across the neck of cerebral aneurysms are capable of reducing aneurysmal flow when coils are not used for filling the aneurysms. It is important to evaluate the effects of flow reduction caused by stent implants used for the treatment of cerebral aneurysms. Subtracted vortex centers path line method (SVC method) is one of the image post processing methods employed for quantitative flow measurement. We developed a modified SVC method by employing Cinematic Angiography (25 frames/s) and digital video recording (30 frames/s) with a commercial digital camera. We successfully compared the flow effectiveness using a tubular silicon model with a sidewall aneurysm. The result suggests that our modified SVC method is useful for a comparative examination of the effect of aneurysmal flow reduction caused by stent implants.

Cinematic Angiography for Measurements of Blood Flow in Cerebral Aneurysms With Stents

Background and Purpose: The assessment of blood flow speed by imaging modalities is important for endovascular treatments, such as stent implantation, of cerebral aneurysms. The subtracted vortex centers path line method (SVC method) is one of the ways of determining flow speed quantitatively using the image sequence. And a cinematic angiography (CA) is a high speed image acquisition system using X-ray and contrast media integrated in Digital Subtraction Angiography (DSA) for endovascular therapy. The combination of SVC and CA may useful for determining the blood flow speed during the operation using DSA. In this study, we applied this combination to analyze hemodynamic changes before and after stenting. Methods: A transparent tubular model was constructed of silicone which included an aneurysm 10 mm in diameter and having a 5 mm neck on a straight parent artery with a diameter of 3.5 mm. The model was integrated into a pulsatile circulation system. A double layer stent was placed in the parent artery on the aneurysm. By CA, successive images at 25 frames per second with injection of contrast were obtained. Results and conclusion: Rotating vortexes of contrast, which advanced along the wall of the aneurysm, were observed in successive images of the aneurysm cavity. The movement distance of the vortex center was measured and the results show that the vortex speed decrease after stenting. This indicates the possibility of applying the SVC method to medical imaging equipment for analysis of the flow in aneurysms containing stent.Copyright

Adjunct Use of a Self-expanding Stent for Treatment of Intracranial Stenosis. A Case Report.

We present a case of a patient who received adjunct treatment with a self-expanding stent after balloon dilatation of a symptomatic stenosis of the carotid siphon. After predilatation, complementary angioplasty with a balloon-expandable stent was abolished due to lack of compliance of the delivery system. Since the vascular anatomy allows for the passage of balloon systems only, the stenosis was further dilated and a self-expanding stent was delivered to avoid the risk of complications related to dissection and vessel recoil. However, problem of in-stent stenosis remains at the long-term follow-up period.

Method to Quantify Flow Reduction in Aneurysmal Cavities of Lateral Wall Aneurysms Produced by Stent Implants Used for Flow Diversion

Stent implants placed across the neck of cerebral aneurysms are capable of reducing aneurysmal flow when coils are not used for filling the aneurysms. It is important to evaluate the effects of flow reduction caused by stent implants used for the treatment of cerebral aneurysms. Subtracted vortex centers path line method (SVC method) is one of the image post processing methods employed for quantitative flow measurement. We developed a modified SVC method by employing Cinematic Angiography (25 frames/s) and digital video recording (30 frames/s) with a commercial digital camera. We successfully compared the flow effectiveness using a tubular silicon model with a sidewall aneurysm. The result suggests that our modified SVC method is useful for a comparative examination of the effect of aneurysmal flow reduction caused by stent implants.