PubMed Central (PMC3 - NLM DTD)
(2,081,148 recursos)
Archive of life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM).
203.
Indications for Cerebral Revascularization for Patients with Atherosclerotic Carotid Occlusion - Derdeyn, Colin P.; Grubb, Robert L.; Powers, William J.
Patients with complete carotid occlusion and recent ischemic symptoms are at high risk for subsequent stroke, particularly those with evidence of severe hemodynamic impairment due to poor collateral flow. Treatment options for these patients include direct extracranial to intracranial arterial bypass, or interventions aimed at improving collateral sources of flow such as endarterectomy or angioplasty and stenting of the ipsilateral external carotid artery, the contralateral carotid artery, or the vertebral arteries. The evidence supporting the use of these procedures for patients with complete occlusion of the carotid artery will be the focus of this article. The use of physiologic imaging...
204.
Surgical Management of Moyamoya Syndrome - Smith, Edward R.; Scott, R. Michael
Moyamoya syndrome, a vasculopathy characterized by chronic progressive stenosis at the apices of the intracranial internal carotid arteries, is an increasingly recognized entity which is associated with cerebral ischemia. Diagnosis is made on the basis of clinical and radiographic findings, including a characteristic stenosis of the internal carotid arteries in conjunction with abundant collateral vessel development. Adult moyamoya patients often present with hemorrhage, leading to rapid diagnosis. In contrast, children usually present with transient ischemic attacks or strokes, which may prove more difficult to diagnose because of patient's inadequate verbal and other skills, leading to delayed recognition of the underlying...
205.
Moyamoya Disease in Adults: The Role of Cerebral Revascularization - Zipfel, Gregory J.; Fox, Douglas J.; Rivet, Dennis J.
Moyamoya disease is a disorder characterized by bilateral progressive steno-occlusion of the terminal internal carotid arteries with associated development of a fragile network of basal collateral vessels. It most commonly presents in children, but is also frequently seen in adults, especially in the third or fourth decade of life. Adults afflicted with this disease have very different clinical characteristics as compared with children. For example, adults more commonly present with hemorrhage than cerebral ischemia, while children present with cerebral ischemia nearly 75% of the time and very rarely present with hemorrhage. This significantly impacts treatment considerations for the adult-onset moyamoya...
206.
Revascularization of the Posterior Circulation - Coert, Bert A.; Chang, Steven D.; Marks, Michael P.; Steinberg, Gary K.
The primary objective of revascularization procedures in the posterior circulation is the prevention of vertebrobasilar ischemic stroke. Specific anatomical and neurophysiologic characteristics such as posterior communicating artery size affect the susceptibility to ischemia. Current indications for revascularization include symptomatic vertebrobasilar ischemia refractory to medical therapy and ischemia caused by parent vessel occlusion as treatment for complex aneurysms. Treatment options include endovascular angioplasty and stenting, surgical endarterectomy, arterial reimplantation, extracranial-to-intracranial anastomosis, and indirect bypasses. Pretreatment studies including cerebral blood flow measurements with assessment of hemodynamic reserve can affect treatment decisions. Careful blood pressure regulation, neurophysiologic monitoring, and neuroprotective measures such as...
207.
Revascularization for Complex Skull Base Tumors - Mura, Jorge; Rojas-Zalazar, David; Oliveira, Evandro de
We discuss revascularization techniques for complex skull base lesions utilizing high-flow arterial bypass. At present, the radial artery is the donor graft utilized in most circumstances at our institution. The knowledge of revascularization techniques is very important to achieve radical resection in lesions where arterial compromise is documented.
208.
Cerebral Revascularization in Skull Base Tumors - Wolfe, Stacey Quintero; Tummala, Ramachandra P.; Morcos, Jacques J.
Skull base tumors involving the carotid artery pose a difficult surgical challenge. The potential for bypass grafting for cerebral revascularization carries inherent risks but may aid in tumor resection and control in those who warrant carotid sacrifice but have inappropriate natural cerebrovascular reserve. We include a review of the literature discussing the indications for carotid resection as part of skull base tumor surgery, indications for cerebral revascularization, balloon test occlusion, graft types and operative technique, complications, and results.
209.
Case Report: Optic Disc Edema without Hydrocephalus in Acoustic Neuroma - Grainger, Joseph; Dias, Palitha S.
Traditionally, visual disturbance and optic disc edema are regarded as late manifestations of acoustic neuromas indicating increased intracranial pressure as a result of obstructive hydrocephalus or a sizeable mass lesion. We report the case of a 56-year-old man who presented with visual disturbance and bilateral optic disc edema. Classic features of hydrocephalus were absent. Magnetic resonance imaging showed a large acoustic neuroma. However, there was no ventriculomegaly and at surgery intracranial pressure was normal. We suggest that cerebrospinal fluid protein may have a role in the formation of optic disc edema through a normal pressure communicating type of hydrocephalus. Furthermore,...
210.
Resolution of Tonsillar Herniation and Cervical Syringomyelia Following Resection of a Large Petrous Meningioma: Case Report and Review of Literature - Fox, Benjamin; Muzumdar, Dattatraya; DeMonte, Franco
We describe a case of a large, petrous meningioma associated with tonsillar herniation and cervical syringomyelia. The patient, a 53-year-old woman, had a 6-month history of a dull, aching pain in the occipital region associated with numbness in the right C2 dermatome and left gaze evoked nystagmus. Magnetic resonance imaging (MRI) revealed a large tumor in the right posterior fossa associated with moderate supratentorial hydrocephalus. Secondary tonsillar herniation and cervical syringomyelia extending from C2 to C6 were also identified. The tumor, later confirmed to be a meningioma originating from the petrous region, was resected completely via a retrosigmoid approach. Postoperative...
212.
Enhanced Exposure of Carotico-Oculomotor Triangle Following Extradural Anterior Clinoidectomy: A Comparative Anatomical Study - Sade, Burak; Kweon, Chang Y.; Evans, James J.; Lee, Joung H.
Objective: To quantify and compare the carotico-oculomotor triangle (COT) area before and after extradural anterior clinoidectomy (AC). Methods: Ten cadaveric heads were dissected bilaterally. Before and after an extradural AC, the following points were measured: (1) the internal carotid artery (ICA) bifurcation to the tip of the anterior clinoid process (ACP) (A) and to the distal dural ring (A?), (2) the ICA bifurcation to the point where the oculomotor nerve becomes obscured by the tentorial fold (B) and to the porus oculomotoris after incision of the tentorial fold (B?), and (3) the tip of the ACP to the point where...
213.
Transcranial Resection of Olfactory Neuroblastoma - Wang, Chih-Chun; Chen, Yao-Liang; Hsu, Yung-Shin; Jung, Shih-Ming; Hao, Sheng-Po
From February 1995 to August 2004 at Chang Gung Memorial Hospital and Chang Gung University, eight patients with an olfactory neuroblastoma underwent transcranial resection alone. The transcranial surgical technique consisted of a bicoronal incision, followed by a standard frontal craniotomy with or without a separated orbital bar osteotomy. The tumor could be removed en bloc transcranially after the cranial base osteotomy according to the tumor extent delineated by preoperative magnetic resonance imaging and intraoperative findings. The defect in the floor of the anterior cranial fossa was reconstructed with a galeopericranial flap. Sinoscopy should compensate rather than compete with the transcranial...
215.
Middle Cerebral Artery Stenosis: Endovascular and Surgical Options - Klopfenstein, Jeffrey D.; Ponce, Francisco A.; Kim, Louis J.; Albuquerque, Felipe C.; Nakaji, Peter; Spetzler, Robert F.
Atherosclerotic middle cerebral artery stenosis is a rare but potentially devastating cause of cerebral ischemia and stroke. While medical management remains the mainstay for stroke prevention, surgical and/or endovascular intervention is indicated in selected patients. This article reviews the role of surgery and endovascular techniques in the treatment of middle cerebral artery stenosis based on its natural history, pathophysiology, and prognosis when treated medically.
216.
ELANA: Excimer Laser-Assisted Nonocclusive Anastomosis for Extracranial-to-Intracranial and Intracranial-to-Intracranial Bypass: A Review - Langer, David J.; Vajkoczy, Peter
ELANA, excimer laser-assisted nonocclusive anastomosis, is a technique using an excimer laser/catheter system for intracranial bypass surgery of the brain. The technique has been developed over the past 12 years by Tulleken and colleagues at UMC Utrecht in The Netherlands for treatment of primarily untreatable giant aneurysms. We review here the emergence of transplanted conduit bypass as a valuable technique for managing these lesions and the subsequent development of ELANA bypass. The ELANA technique allows the operating surgeon to perform an extracranial-to-intracranial or intracranial-to-intracranial bypass using a transplanted large caliber conduit without occlusion of the recipient artery, thus eliminating intraoperative...
217.
Extracranial-to-Intracranial Bypass Using Radial Artery Grafting for Complex Skull Base Tumors: Technical Note - Abdulrauf, Saleem I.
The management of complex skull base tumors that incorporate large intracranial vessels poses challenging questions. Patients who fail initial surgical resection and adjunctive therapies (i.e., radiosurgery) who present with tumor regrowth may be candidates for parent vessel occlusion and total tumor resection in combination with extracranial-to-intracranial (EC-IC) bypass to augment the sacrificed vessel territory. In this technical report, we delineate the surgical technique of performing an EC-IC bypass using a radial artery graft. Our protocol of simultaneous cranial, neck, and forearm dissections by the surgical team to perform this procedure is described in detail.
218.
Assessing Success after Cerebral Revascularization for Ischemia - Wanebo, John E.; Amin-Hanjani, Sepideh; Boyd, Cynthia; Peery, Terry
Cerebral revascularization continues to evolve as an option in the setting of ischemia. The potential to favorably influence stroke risk and the natural history of cerebrovascular occlusive disease is being evaluated by the ongoing Carotid Occlusion Surgery Study and the Japanese Extracranial-Intracranial Bypass Trial. For those patients who undergo bypass in the setting of ischemia, four key areas of follow-up include functional neurological status, neurocognitive status, bypass patency, and status of cerebral blood flow and perfusion. Several stroke scales that can be used to assess functional status include the National Institutes of Health Stroke Scale, Bathel Index, Modified Rankin Scale,...
219.
Learning to Perform Microvascular Anastomosis - MacDonald, Joel D.
The skills necessary to connect ultrasmall vessels and neural structures successfully require commitment and practice to refine. The techniques require only a few specialized instruments and a high-quality microscope. Several exercises can simulate real-life anatomical situations using a rubber sheet, chicken vessels, or the rat femoral artery model. A series of graduated drills can help develop proficiency and confidence.
220.
Graft Harvesting for Revascularization in the Head and Neck - Johnson, Terence E.; Wanebo, John E.; Bayles, Stephen W.; Liu, Charles Y.
The techniques for revascularization in the neurocranium, skull base, and neck continue to evolve at an exciting pace. In this body of literature, however, techniques for harvesting radial artery and saphenous vein grafts are mainly reported using traditional open techniques. Minimally invasive procedures are fast becoming an alternative to open techniques in many fields and have the potential to become the standard of care. The cardiovascular literature is replete with reports of endoscopically harvested vascular grafts. This article reviews both methods, since the current state of the art involves knowledge of open and endoscopic harvesting techniques.
201.
