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Purpose: The purpose of this work was to assess the potential and limitations of a contrast-enhanced time-resolved MR angiography technique for evaluation of spinal vascular malformations. Method: Two patients with intramedullary arteriovenous (AV) malformations and three patients with dural AV fistula underwent four serial acquisitions, every 17-20 s, of 20-32 coronal 1.5- to 2-mm-thick partitions with a fast 3D SPGR sequence after injection of 0.2-0.3 mmol/kg paramagnetic contrast agent. This was followed by coronal 3D and sagittal or coronal 2D phase contrast (PC) MR angiography. Results: No spinal vessels were visualized in the first (baseline) series. In patients with intramedullary AV malformations, the arterial feeders, nidus, and perimedullary draining veins were visualized in the second (early) series. In the third (intermediate) series, the arterial feeder vanished, whereas the intercostal and lumbar veins appeared. In patients with dural AV fistula, abnormal intraspinal vessel appeared in the third series and persisted, although less conspicuous, in the fourth (late) series. Contrast-enhanced time-resolved MR angiography demonstrated the venous components of the lesion with better conspicuity than 3D PC MR angiography, whereas it was inferior for visualization of arterial feeders. Moreover, indirect identification of the level of the dural AV fistula was possible only on the phase display of the 2D PC MR angiography. Conclusion: Contrast-enhanced time-resolved MR angiography is a useful complement to PC MR angiography for the evaluation of spinal vascular malformation. Index Terms: Magnetic resonance-Magnetic resonance angiography-Spinal cord, abnormalities.

A 75-year-old man underwent yearly follow-up carotid Duplex scanning after carotid endarterectomy (CEA), performed 3 years ago, because of the presence of a large atherosclerotic plaque at the bifurcation of left common carotid artery with severe stenosis (80%). A residual atheroma was present post-CEA with a small stenosis. His medical history was notable for well-controlled …

A review of 4,500 angiograms yielded 11 patients with dissection of the vertebral arteries who had MRI and (in 4 patients) MR angiography (MRA) in the acute phase of stroke. One patient with incidental discovery at arteriography of asymptomatic vertebral artery dissection and two patients with acute strokes with MRI and MRA findings consistent with vertebral artery dissection were included. Dissection occurred after neck trauma or chiropractic manipulation in 4 patients and was spontaneous in 10. Dissection involved the extracranial vertebral artery in 9 patients, the extra-intracranial junction in 1, and the intracranial artery in 4. MRI demonstrated infarcts in the brain stem, cerebellum, thalamus or temporo-occipital regions in 7 patients with extra- or extra-intracranial dissections and a solitary lateral medullary infarct in 4 patients (3 with intracranial and 1 with extra-intracranial dissection). In 2 patients no brain abnormality related to vertebral artery dissection was found and in one MRI did not show subarachnoid haemorrhage revealed by CT. Intramural dissecting haematoma appeared as crescentic or rounded high signal on T1-weighted images in 10 patients examined 3-20 days after the onset of symptoms. The abnormal vessel stood out in the low signal cerebrospinal fluid in intracranial dissections, whereas it was more difficult to detect in extracranial dissections because of the intermediate-to-high signal of the normal perivascular structures and slow flow proximal and distal to the dissection. In two patients examined within 36 h of the onset, mural thickening was of intermediate signal intensity on T1-weighted images and high signal on spin-density and T2-weighted images. MRA showed abrupt stenosis in 2 patients and disappearance of flow signal at and distal to the dissection in 5. Follow-up arteriography, MRI or MRA showed findings consistent with occlusion of the dissected vessel in 6 of 8 patients.

A previously healthy 34-year-old man was admitted because of motor vehicle accident. In the Emergency Room, the patient was alert and oriented [Glasgow Coma Score (GCS) was 15] and physical examination showed a fracture of the right femoral shaft. The results of laboratory investigations, computed tomographic (CT) scan of the head and chest radiograph were all normal. A decision was made to treat the fracture by closed reduction and fixation with an intramedullary nail. Ten hours after orthopedic surgery, the second day after the injury, the patient was transferred to our Emergency Medicine Department because of his consciousness suddenly deteriorated: GCS was 8 and he developed confusion and agitation, but without focal signs; hemodynamic and respiratory findings remained stable. CT scan of the head, obtained later that day, was unremarkable. On day 2 after surgery, a T2-weighted and fluid-attenuated inversion recovery magnetic resonance images (MRI) of the brain revealed multiple nodular and punctate foci of high signal intensity, located in the white matter (subcortical white matter and centrum semiovale). The MRI findings were consistent with cerebral fat embolism, which causes breakdown of the blood-brain barrier with vasogenic edema or cytotoxic edema or both. The patient's GCS started to improve gradually on day 4 after admission, and by day 7, she had regained full consciousness. He was discharged from hospital without sequels and was subsequently found in excellent clinical condition at a follow-up visit six months later.

To evaluate the role of magnetic resonance (MR) angiography in the assessment of spinal vascular malformation therapy.Thirty-four patients with spinal vascular malformations (30 dural arteriovenous fistulas, two perimedullary arteriovenous fistulas, and two intramedullary arteriovenous malformations) underwent MR angiography and MR imaging before and after endovascular or surgical treatment.MR angiography showed residual flow in perimedullary vessels in seven patients with dural fistula after embolization with liquid adhesive. In all seven, treatment failure was confirmed with arteriography. Long-lasting disappearance of flow in perimedullary vessels was demonstrated at MR angiography in 22 patients with dural fistula. MR imaging demonstrated normalization of spinal cord volume in 16 of 22 patients and signal intensity on T2-weighted images in three patients. Disappearance of cord enhancement was observed in five of 21 patients and of perimedullary enhanced vessels in six of 13 patients. In one additional patient with dural fistula treated with embolization, early posttreatment MR angiography showed disappearance of flow in perimedullary vessels, which reappeared at follow-up and was consistent with reopening of a small residual fistula. Posttreatment MR angiography demonstrated transient reduction of flow in the nidus in two patients with intramedullary malformations treated with embolization. Permanent disappearance of flow in the perimedullary vessel was seen after endovascular treatment in two patients with perimedullary fistula.MR angiography is more sensitive than MR imaging in depicting residual or recurrent flow in peri- or intramedullary vessels, which indicates patency of the vascular malformation.