Middle meningeal arteries with and without transdural anastomosis in Moyamoya disease can be distinguished using intraoperative Doppler sonography

Transdural anastomosis (TA) from the middle meningeal arteries (MMAs) to the brain is important in maintaining cerebral blood flow in patients with Moyamoya disease. A 16-year-old adolescent girl presented with a transient ischemic attack. Preoperative cerebral angiography revealed TA from the MMA. During surgery, the MMA was exposed on the dural surface directly under the burr hole. Measurement of flow velocity in the MMA with an ultrasonic blood flowmeter revealed increased diastolic flow velocity. As the MMA was assumed to contribute to TA, a new burr hole was made to preserve the MMA, and a bone flap was prepared. Direct and indirect bypass surgeries were performed. Electrocoagulation was not applied to the MMA associated with TA, but the artery was compressed with gelfoam containing fibrin glue to achieve hemostasis. Postoperatively, no evidence of cerebral infarction was detected. Determining which of several MMAs exposed in the surgical field is associated with TA can be difficult. However, measurement of flow velocity with an ultrasonic blood flowmeter to confirm increased flow velocity in the diastolic phase is useful for confirming the presence or absence of TA from the extracranial arteries including the MMA.

Progressive alterations of perilesional brain tissue after Gamma Knife stereotactic radiosurgery: a diffusion tensor imaging study

To search for microstructural lesions of normal-appearing cerebral white matter surrounding a tumor or a vascular lesion, after single-fraction stereotactic Gamma Knife (GK) radiosurgery.In 43 patients with different brain lesions, magnetic resonance including diffusion tensor imaging (DTI) was performed before and after GK radiosurgery and change of parameters was measured in areas surrounding the lesion.Outside the lesion, there was an increase in mean diffusivity (MD) and radial diffusivity (RD) between 2.1% and 3.4% in the 15–10 Gy and in the 10–5 Gy perilesional isodose volumes, which reached statistical significance (pairedWe report some minor, but nevertheless significant changes in DTI parameters in normal-appearing perilesional brain tissue after GK radiosurgery progressing with time, which partially may be induced by the radiation itself and partially may be due to indirect effects of lesion reactions to the radiation. Follow-up studies are necessary for further characterization of these changes and assessment of their time course.

Flow diverters for intracranial aneurysms

The progressive establishment of endovascular management in treating intracranial aneurysms had lead to continuous technique advancements and development of innovative technologies. Flow diverters are “stent-like” devices currently used for complex unruptured aneurysms allowing endoluminal reconstruction of the parent artery and occlusion of the aneurysm sac. In the present article, we review the development of flow diversion devices through

Part II: an evaluation of an integrated systems approach using diffusion-weighted, image-guided, exoscopic-assisted, transulcal radial corridors

Subcortical injury resulting from the surgical access and management of lesions in the sensorimotor area is associated with a high degree of cognitive and functional morbidity.We used a systems approach integrating the six core competencies of the 6 Pillar approach: 1) image interpretation and trajectory planning; 2) dynamic navigation; 3) radial transulcal access and cannulation; 4) exoscopic high-definition optics; 5) resection with automated nonthermal mechanical instrumentation; and 6) regenerative medicine. We describe the application of the 6 Pillar approach to 13 consecutive patients with lesions in the sensorimotor area.Eight females and five males with lesions in the sensorimotor area were treated using the 6 Pillar approach. There were eight tumors, one abscess, and four primary intracranial hemorrhages. Fifteen procedures were performed. Postoperatively, seven patients improved neurologically (three tumors, one abscess, and three ICHs), five remained unchanged, and one patient died. There was no worsening of pre-existing deficits.The integration of the 6 Pillar approach provides a safe and effective parafascicular minimally invasive corridor to subcortical lesions involving the sensorimotor area. Future studies will be needed to determine long-term efficacy, durability, and degree of resection within each category.

Endoscope-integrated indocyanine green video-angiography for cerebral aneurysm surgery: a more effective technique

Microscope-integrated indocyanine green video-angiography (mICG-VA) is used as an adjunct to aneurysm surgery in checking for small compromised perforating arteries and the remnant of an aneurysmal neck. A limitation of mICG-VA is the inability to access the deep area where small vessels are located behind the aneurysm sac or the parent artery. The endoscope-integrated ICG-VA (eICG-VA) is not only a tool in obtaining a wide angle of surgical view, but also is a technique to detect real-time blood flow during aneurysm clipping.Patients with an unruptured cerebral aneurysm who had conventional endoscope-assisted microsurgery and eICG-VA were enrolled. We compared the efficacy and additional details of imaging from both types of procedures.The data of seven patients were reviewed. In two cases of small perforating arteries that were hidden by the aneurysm sacs, more details were detected by eICG-VA. While the performance of the conventional technique was limited, the eICG-VA revealed a wide view in the deep area during aneurysm clipping.The eICG-VA provides more details of the aneurysm, especially in small perforating vessels that were hidden by the aneurysm. It can resolve the limitations of the conventional endoscope and mICG-VA.