3D angiography. Clinical interest. First applications in interventional neuroradiology.
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3D angiography is a true technical revolution that allows improvement in the quality and safety of diagnostic and endovascular treatment procedures. 3D angiography images are obtained by reconstruction of a rotational angiography acquisition done on a C-arm (GE Medical Systems) spinning at 40 degrees per second. The carotid or vertebral selective injection of a total of 15 ml of non-ionic contrast media at 3 ml/sec over 5 seconds allows the selection of the "arterial phase". Four hundred sixty 3D angiographic studies were performed from December 1996 to September 1998 on 260 patients and have been analyzed in MIP (Maximum Intensity Projection) and SSD (Shaded Surface Display) views. The exploration of intracranial aneurysms is simplified and only requires, for each vascular axis, a biplane PA and Lateral run followed by a single rotational angiography run. The 3D angiography image is available on the workstation's screen (Advantage Workstation 3.1, GE Medical Systems) in less than 10 minutes after the acquisition of the rotational run. It therefore allows one to analyze, during the intervention, the aneurysm's angioarchitecture, in particular the neck, and select the best therapeutic technique. When endovascular treatment is the best indication, 3D angiography allows one to define the optimal angle of view and accurately select the microcoils dimensions. 3D angiography replaces the multiple oblique views that used to be required to analyze the complex aneurysms and therefore allows a reduction of the total contrast medium quantity, the patient X-ray dose and the length of the intervention time which is a safety factor. Also, in particular for complex cases, it brings additional elements complementing the results of standard 2D DSA and rotational angiograms. In the cervical vascular pathology, 3D angiography allows for a better assessment of the stenosis level and of dissection lesions. Our current research activities focus on the matching without stereotactic frame between 3D X-ray angiography and volumetric MR acquisition, which should allow us to improve the treatment of intracerebral arterio-venous malformations (AVMs). (+info)
Rupture mechanism of a thrombosed slow-growing giant aneurysm of the vertebral artery--case report.
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A 76-year-old male developed left hemiparesis in July 1991. The diagnosis was thrombosed giant vertebral artery aneurysm. He showed progressive symptoms and signs of brainstem compression, but refused surgery and was followed up without treatment. He died of rupture of the aneurysm and underwent autopsy in March 1995. Histological examination of the aneurysm revealed fresh clot in the aneurysmal lumen, old thrombus surrounding the aneurysmal lumen, and more recent hemorrhage between the old thrombus and the inner aneurysmal wall. The most important histological feature was the many clefts containing fresh blood clots in the old thrombus near the wall of the distal neck. These clefts were not lined with endothelial cells, and seemed to connect the lumen of the parent artery with the most peripheral fresh hemorrhage. However, the diameter of each of these clefts is apparently not large enough to transmit the blood pressure of the parent artery. Simple dissection of the aneurysmal wall by blood flow in the lumen through many clefts in the old thrombus of the distal neck may be involved in the growth and rupture of thrombosed giant aneurysms of the vertebral artery. (+info)
Bilateral vertebral artery occlusion following cervical spine trauma--case report.
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A 41-year-old female presented with a rare case of bilateral vertebral artery occlusion following C5-6 cervical spine subluxation after a fall of 30 feet. Digital subtraction angiography showed occlusion of the bilateral vertebral arteries. Unlocking of the facet joint, posterior wiring with iliac crest grafting, and anterior fusion were performed. The patient died on the 3rd day after the operation. This type of injury has a grim prognosis with less than a third of the patients achieving a good outcome. (+info)
Pseudoaneurysm of the vertebral artery.
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Pseudoaneurysms of the vertebral artery are rare. Their treatment depends on the location, size, cause, and coexisting injuries. The surgical management of a 22-year-old man who had a large pseudoaneurysm in the 1st portion of the right vertebral artery is described, and an additional 144 cases from the medical literature are briefly reviewed. (+info)
Outcome of angioplasty for atherosclerotic intracranial stenosis.
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BACKGROUND AND PURPOSE: We sought to assess the long-term outcome and efficacy of percutaneous transluminal angioplasty in the treatment of symptomatic intracranial atherosclerotic stenoses. METHODS: Twenty-three patients with fixed symptomatic intracranial stenoses were treated over a 5-year period with percutaneous transluminal angioplasty. Patients who underwent successful angioplasty were followed up for 16 to 74 months (mean, 35.4 months). RESULTS: An angioplasty that resulted in decreased stenosis was performed in 21 of 23 patients (91.3%). In 1 case a stenosis could not be safely crossed, and in another balloon dilatation resulted in vessel rupture. This vessel rupture resulted in the 1 periprocedural death in the series. In follow-up there was 1 stroke in the same vascular territory as the angioplasty and 2 strokes in the series overall. This yielded an annual stroke rate of 3.2% for strokes in the territory appropriate to the site of angioplasty. CONCLUSIONS: Intracranial angioplasty can be performed with a high degree of technical success. The long-term clinical follow-up available in this series suggests that it may reduce the risk of future stroke in patients with symptomatic intracranial stenoses. (+info)
Clinical and neuroradiological features of intracranial vertebrobasilar artery dissection.
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BACKGROUND AND PURPOSE: We sought to determine the clinical and neuroradiological features of intracranial vertebrobasilar artery dissection. METHODS: The clinical features and MR findings of 31 patients (20 men and 11 women) with intracranial vertebrobasilar artery dissections confirmed by vertebral angiography were analyzed retrospectively. The vertebral angiography revealed the double lumen sign in 11 patients (13 arteries) and the pearl and string sign in 20 patients (28 arteries). RESULTS: The patients ranged in age from 25 to 82 years (mean, 54.8 years). Clinical symptoms due to ischemic cerebellar and/or brain stem lesions were common, but in 3 cases the dissections were discovered incidentally while an unrelated disorder was investigated. Headache, which has been emphasized as the only specific clinical sign of vertebrobasilar artery dissection, was found in 55% of the patients. Intramural hematoma on T1-weighted images has been emphasized as a specific MR finding. The positive rate of intramural hematoma was 32%. Double lumen on 3-dimensional (3-D) spoiled gradient-recalled acquisition (SPGR) images after the injection of contrast medium was identified in 87% of the patients. The 3-D SPGR imaging method is considered useful for the screening of vertebrobasilar artery dissection. CONCLUSIONS: Intracranial vertebrobasilar artery dissection is probably much more frequent than previously considered. Such patients may present no or only minor symptoms. Neuroradiological screening for posterior circulation requires MR examinations, including contrast-enhanced 3-D SPGR. Angiography may be necessary for the definite diagnosis of intracranial vertebrobasilar artery dissection because the sensitivity of the finding of intramural hematoma is not satisfactory. (+info)
Perimesencephalic hemorrhage. Exclusion of vertebrobasilar aneurysms with CT angiography.
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BACKGROUND AND PURPOSE: It is important to recognize a perimesencephalic pattern of hemorrhage in patients with subarachnoid hemorrhage (SAH), because in 95% of these patients the cause is nonaneurysmal and the prognosis is excellent. The purpose of this study was to investigate whether CT angiography can accurately exclude vertebrobasilar aneurysms in patients with perimesencephalic patterns of hemorrhage and therefore replace digital subtraction angiography (DSA) in this setting. METHODS: In 40 patients with posterior fossa SAH as shown on unenhanced CT, 2 radiologists independently evaluated unenhanced CT for distinguishing between perimesencephalic and nonperimesencephalic pattern of hemorrhage and assessed CT angiography for detection of aneurysms. All patients subsequently underwent DSA or autopsy. RESULTS: Observers agreed in 38 of 40 patients (95%) in differentiating perimesencephalic and nonperimesencephalic patterns of hemorrhage on unenhanced CT. On the CT angiograms, both observers detected a vertebrobasilar aneurysm in 16 patients and no aneurysm in 24 patients. These findings were confirmed by DSA or autopsy. No patients with a perimesencephalic pattern of hemorrhage were found to have an aneurysm on either CT angiography or DSA. CONCLUSIONS: Good recognition of a perimesencephalic pattern of hemorrhage is possible on unenhanced CT, and CT angiography accurately excludes and detects vertebrobasilar aneurysms. DSA can be withheld in patients with a perimesencephalic pattern of hemorrhage and negative CT angiography. (+info)
Management of aneurysms of the vertebral artery-posterior inferior cerebellar artery complex.
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Aneurysms of the vertebral artery (VA) and posterior inferior cerebellar artery (PICA) account for only about 3% of all diagnosed intracranial aneurysms. The surgical therapy of these aneurysms is complex and difficult due to the close topographical relationship between the neurovascular structures. Here, we report upon 27 patients with 29 such aneurysms. Of these, 22 patients (81%) were hospitalized because of a subarachnoid hemorrhage. Sixteen of these patients (72%) had an additional intraventricular hemorrhage. Twenty-one patients (78%) were surgically treated for their aneurysms, three of them also for an associated arteriovenous malformation. Aneurysms of the VA and the proximal PICA were exposed via a transcondylar (n = 11) or lateral suboccipital (n = 3) approach, those originating from the distal PICA via a paramedian suboccipital (n = 7) route. Endovascular therapy was used in three patients. A patient with a fusiform aneurysm of the vertebrobasilar junction was treated with a ventriculoperitoneal shunt only. Three aneurysms with a complex morphology were not treated. Of the patients operated upon, two died postoperatively due to vasospasm. Two other patients developed an incomplete dorsolateral medullary syndrome. One individual was lost for follow-up. The median follow-up period was 4.6 years (range 3-86 months). Both, the overall mortality (2/27) and morbidity (2/27) were 7.5%, respectively. Our results show that even complex vascular lesions of the posterior fossa can be treated with a satisfactory long-term outcome in the majority of our patients (85%). The multimodal management and an individually tailored microsurgical approach are key issues for the treatment of such aneurysms. (+info)