iEEG-BIDS, extending the Brain Imaging Data Structure specification to human intracranial electrophysiology

The Brain Imaging Data Structure (BIDS) is a community-driven specification for organizing neuroscience data and metadata with the aim to make datasets more transparent, reusable, and reproducible. Intracranial electroencephalography (iEEG) data offer a unique combination of high spatial and temporal resolution measurements of the living human brain. To improve internal (re)use and external sharing of these unique data, we present a specification for storing and sharing iEEG data: iEEG-BIDS

Carotid Endarterectomy: To Shunt or Not to Shunt?

Carotid endarterectomy is now the third most common operation performed in the United States.1 Concerns have been raised about the lack of proper indications for surgery in many patients, the risks of angiography, the surgical morbidity and mortality across the United States, and the overuse of intraoperative monitoring and shunting.1-3The most generally accepted indication for carotid endarterectomy is the development of a transient ischemic attack in a patient who is subsequently found to have significant unilateral stenosis at or near the origin of the internal carotid artery (residual lumen diameter less than 2.0 mm, causing a hemodynamic change) or a deep ulceration. When the patient's medical condition is stable and the operation is done by an experienced team with the patient under general anesthesia, the risk of mortality is approximately 1% and the risk of stroke morbidity is less than 3%3-7 When there is significan

Superior Temporal Gyrus Approach to Middle Cerebral Artery Aneurysms

Abstract Aneurysms of the bifurcation of the middle cerebral artery (MCA) can be approached through a small incision in the anterior portion of the superior temporal gyrus. The pterion and the lateral aspect of the lesser wing of the sphenoid bone are removed. The aneurysm is approached, using microsurgical techniques, by following the main divisions of the MCA to the parent trunk and the base of the aneurysm. Once the parent vessel and the origin of the major divisions are clearly identified, it is usually preferable to dissect and mobilize the entire aneurysmal complex to elucidate the anatomy and prepare the neck for clipping. This approach offers the advantages of minimal brain retraction and minimal manipulation of the main trunk and perforators of the MCA. In addition, it allows a more complete exposure of the aneurysmal complex and facilitates dissection behind the aneurysm, which is more difficult when the aneurysm is approached from the front by opening the sylvian fissure medially to laterally. A potential disadvantage of this method is that proximal control is not obtained until the base of the aneurysm is reached, but this has not been a problem in our experience. Other disadvantages are the need for a slightly larger bone flap and the potentially increased risk of epilepsy. This approach is not suitable when the main trunk of the MCA is short and the aneurysm is in front of the insula. It is also not recommended for the rare cases in which the aneurysm points back over the insula. During a 6-year period, this approach was used in 49 of 58 cases of MCA aneurysm. The only deaths in this group occurred in patients who were in deep coma before operation. Two patients were made worse by operative complications, and 2 more worsened as a result of postoperative vasospasm. There was a significant incidence of thrombophlebitis and pulmonary embolism in this series

Emergency carotid endarterectomy

✓ A retrospective review of carotid endarterectomies performed by the Neurosurgical Service at Massachusetts General Hospital from July, 1976, through December, 1985, disclosed 64 procedures that were performed on an emergency basis. The patients included 40 men and 24 women, with a mean age of 64 years (range 32 to 87 years). Correlation of angiographic findings with outcome revealed that of the 27 patients with severe stenosis, usually with delay in blood flow, 25 (93%) were the same or improved postoperatively; of the 11 patients with stenosis and an intraluminal filling defect (six of whom had an intraluminal clot), eight (73%) were the same or improved after surgery; of the 16 patients with complete occlusion, 14 (88%) were the same or improved (backflow was established in all cases); and of the 10 patients with moderate to severe stenosis and/or severe ulceration (including three with transient ischemic attacks who were receiving heparin), eight (80%) were the same or improved. Pre- and postoperative clinical status were graded into five categories: intact; mild deficit; moderate deficit (significant impairment but able to perform activities of daily living); severe deficit (requiring assistance for daily activities); and death. Of the 36 patients who preoperatively were intact or had mild deficits, 33 (92%) were the same or improved postoperatively, three were worse, and there were no deaths. Among 15 patients presenting with moderate deficits, 12 (80%) were the same or improved, two were worse, and one died. Of the 13 patients with severe deficits, 10 (77%) were the same or improved and three died. Two patients with sudden severe deficits associated with loss of contralateral bruit were operated on without angiography and were intact postoperatively. Of the four deaths in the total series, two were attributed to cardiac causes and two to unrelated disease processes. The indications for emergency carotid endarterectomy are discussed

Large and Giant Paraclinoid Aneurysms: Surgical Techniques, Complications, and Results

Abstract Twenty-five patients with giant (>25 mm in diameter) and 9 patients with large (15 to 25 mm in diameter) aneurysms of the internal carotid artery in the ophthalmic or paraophthalmic region are reviewed. In 23 of these patients the aneurysm was clipped directly. There was 1 death in this group, and none of the survivors had disabling neurological complications outside the visual system. The other 11 patients were treated by a trapping procedure or by either common carotid ligation or internal carotid ligation in the neck. Of the 5 patients treated by internal carotid ligation preceded by an extracranial to intracranial bypass graft, 3 developed embolic complications, which in 1 patient resulted in death. One of the 4 patients treated by ligation of the common carotid artery died 1 year later from a recurrent subarachnoid hemorrhage. Of the total group, 18 patients had visual loss preoperatively as a result of aneurysmal compression; in 10 the vision was improved by operation, in 3 it was made worse, and in 2 it was unchanged. In another patient the vision continued to deteriorate slowly after common carotid occlusion, and the other 2 patients died postoperatively before vision could be assessed. The complications in the patients are described and analyzed in detail. Maneuvers found to be of value in the direct approach to these lesions are described. Of these, exposure of the internal carotid artery in the neck for temporary occlusion during clipping and thorough drilling of the anterior clinoid process and unroofing of the optic canal were particularly helpful. The literature on indirect methods of treatment by carotid occlusion with and without bypass graft is reviewed with special reference to the complications and effectiveness of each alternative. Based on this review of the literature and our experience, a treatment scheme is suggested for these aneurysms depending on their mode of presentation

Direct spinal arteriovenous fistula: a new type of spinal AVM Case report

✓ A patient presenting with progressive paraparesis was found to have a spinal arteriovenous fistula at the T3–4 vertebral level. The lesion consisted of a direct communication of the anterior spinal artery with a very distended venous varix that drained mostly superiorly to the posterior fossa and simulated a posterior fossa arteriovenous malformation (AVM) on vertebral angiography. The patient was treated by surgical ligation of the fistula through an anterior transthoracic approach. He deteriorated abruptly on the 4th postoperative day, probably because of retrograde thrombosis of the enlarged anterior spinal artery. Over the next few months, he improved to the point of being able to walk with crutches. He has also regained sphincter control. The different types of spinal AVM's are reviewed. Our case does not fit into any of these groups. A new category, Type IV, is proposed to designate direct arteriovenous fistulas involving the intrinsic arterial supply of the spinal cord

Primary intracranial leiomyosarcoma Case report

✓ A case of primary intracranial leiomyosarcoma is presented, with clinical, radiological, light microscopic, immunohistochemical, and ultrastructural data. The histogenesis is discussed and the literature on smoothmuscle tumors of the central nervous system is reviewed