Cerebral cavernous malformations: serial magnetic resonance imaging findings in patients with and without gamma knife surgery.
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To classify the cerebral cavernous malformations and to investigate the natural history of cavernous malformations according to the classification, 41 patients with 61 cavernous malformations (40 cavernous malformations from 22 patients treated with gamma knife surgery) were regularly followed up using magnetic resonance (MR) imaging for a mean period of 25.5 months in treated cavernous malformations and 20.7 months in untreated cavernous malformations, respectively. Cavernous malformations were classified into four types: type I, extralesional gross hemorrhage beyond cavernous malformation; type II, mixture of subacute and chronic hemorrhage; type III, area of hemosiderin with small central core; and type IV, area of hemosiderin deposition without central core. Follow-up MR images were analyzed to evaluate changes in size, signal intensity, rebleeding, and perilesional adverse reaction of irradiation. A total of 61 cavernous malformations including 17 in type I, 23 in type II, 10 in type III, and 11 in type IV showed usual degradation of blood product in 22 cavernous malformations, no change in shape and signal intensity in 31 cavernous malformations, and eight cavernous malformations with rebleedings in the serial MR images. In these eight cavernous malformations with rebleedings, six occurred in type II and two in type III, but none in type I or IV. Rebleedings were more frequent in type II than in other types (p = 0.044). Adverse reaction of irradiation was observed in five of 22 patients treated with gamma knife surgery. Although most cerebral cavernous malformations showed evolution of hemorrhage or no change in size or shape on follow-up MR images, cerebral cavernous malformations represented as mixture of subacute and chronic hemorrhage with hemosiderin rim (type II) have a higher frequency to rebleed than other types of cerebral cavernous malformations. Cerebral cavernous malformations represented as hemosiderin deposition without central core (type IV) have a lower tendency to rebleed than other types and do not need any treatment. Most of the adverse reaction of irradiation after gamma knife surgery around cavernous malformations are transient findings and are considered to be perilesional edema. (+info)
Fatal haemorrhage from Dieulafoy's disease of the bronchus.
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A 70 year old woman with a previous history of healed tuberculosis and suspected chronic obstructive pulmonary disease presented with recurrent haemoptysis and respiratory failure from a lobar pneumonia. Massive bleeding occurred when biopsy specimens were taken during bronchoscopy which was managed conservatively, but later there was a fatal rebleed from the same site. Two different Dieulafoy's vascular malformations were found in the bronchial tree at necropsy, one of which was the biopsied lesion in the left upper lobe. This report confirms the possibility that vascular lesions occur in the bronchial tree. It is suggested that, if such lesions are suspected at bronchoscopy, bronchial and pulmonary arteriography with possible embolotherapy should be performed. (+info)
Paravertebral arteriovenous malformations with epidural drainage: clinical spectrum, imaging features, and results of treatment.
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BACKGROUND AND PURPOSE: Arteriovenous malformations (AVMs) of the spine or spinal cord can be characterized as spinal cord AVMs, spinal cord and dural arteriovenous fistulas, and AVMs occurring outside the dura but draining into the epidural veins. The purpose of this study was to review the clinical spectrum, imaging features, and results of treatment of paravertebral arteriovenous malformations (PVAVMs) with epidural drainage. METHODS: The clinical records and images of 10 patients with PVAVMs were analyzed retrospectively for clinical presentation, MR findings, angioarchitecture, pathophysiology, treatment efficacy, and clinical follow-up. RESULTS: Seven patients had myelopathy. The MR findings for three of these patients showed spinal cord hyperintensity on T2-weighted sequences and prominent perimedullary vessels. Angiography, performed in two of the three patients, showed evidence of reflux into the perimedullary veins from the PVAVMs. Each of these two patients underwent surgical clipping of the radicular vein leading to the perimedullary veins. In three of the seven patients, there were large epidural veins compressing the cord. Angiography performed in these patients showed large PVAVMs with multiple feeders, which were treated by a combination of transarterial and transvenous embolization. One of the seven patients had an associated spinal cord arteriovenous malformation. In three patients with incidental PVAVMs, cure was achieved by using a combination of coils and liquid adhesives by the endovascular route. CONCLUSION: The clinical presentation of PVAVMs is variable, and symptomatic lesions are the result of compression by epidural veins or of congestive myelopathy. A clear understanding of the anatomy and pathophysiology is necessary to plan treatment. Endovascular techniques are capable of curing the malformation, alleviating the symptoms, or both in a significant proportion of these lesions. (+info)
The transcription factor MEF2C-null mouse exhibits complex vascular malformations and reduced cardiac expression of angiopoietin 1 and VEGF.
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The MEF2 family of transcription factors has been implicated in transcriptional regulation in a number of different cell types. Targeted deletion of the MEF2C gene, in particular, revealed its importance for early cardiogenesis (Q. Lin et al., 1997, Science 276, 1404-1407). We report here that this deletion also resulted in vascular anomalies characterized by extreme variability in lumen size and defects in remodeling. While primary vascular networks formed in the yolk sac of the mutants, they failed to remodel into more complex vascular structures. Likewise, although the primordia of the dorsal aortae formed normally, anomalies were observed in these vessels later in development. Dorsal and anterior to the heart, the aortae exhibited abnormally small lumens, as did the anterior cardinal veins and intersegmental arteries. In contrast, the dorsal aortae and intersegmental arteries caudal to the heart were grossly enlarged. Cranial vessels were also enlarged and less branched than normal. Endocardiogenesis in the mutant was abnormal with the endothelial cells exhibiting a number of aberrant phenotypes. These endocardial defects were accompanied by a notable reduction in angiopoietin 1 and VEGF mRNA production by the myocardium, indicating that MEF2C is required for myocardial expression of these important endothelial-directed cytokines and thus for correct endocardial morphogenesis. (+info)
A large pelvic arteriovenous malformation in an adult patient with cystic fibrosis.
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We present a prepubertal male cystic fibrosis patient with high circulating oestrogen levels (as a consequence of sever cystic-fibrosis-related hepatobiliary disease) who subsequently developed a large pelvic arteriovenous malformation. This has not previously been described in patients with cystic fibrosis, despite the association between high oestrogen levels and arteriovenous malformations. The aetiology and treatment options of arteriovenous malformations are discussed. (+info)
Endovascular treatment of a cervical paraspinal arteriovenous malformation via arterial and venous approaches.
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We describe a cervical congenital paraspinal arteriovenous malformation (AVM) drained by paraspinal and epidural ectatic veins, which caused massive erosion of the C6 and C7 vertebral bodies, threatening the cervical stability and necessitating treatment. During the first session, six arterial embolizations were performed to reduce the size and the flow of the AVM. Two months later, a venous approach was used to occlude the remnant venous exit of the AVM and achieve a complete cure. All embolizations were performed using N-butylcyanoacrylate. (+info)
Transcatheter embolization of arteriovenous malformations in Cowden disease.
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A patient with Cowden disease and multiple arteriovenous malformations (AVMs) that resulted in high output heart failure is described. Cowden disease is a familial syndrome characterized by endodermal, mesodermal and ectodermal dysplasia causing benign and malignant tumors of the skin, breast, gastrointestinal tract, and thyroid gland. Our patient had gastrointestinal polyposis, a right renal tumor, a left lung tumor, an adenomatous goiter, and typical dermatologic findings such as facial papules, acral keratosis, gingival papillomatosis and hemangiomas. AVMs were observed in the pelvis, cervical vertebra, liver, and right supraclavicular area. Transcatheter embolization was performed 7 times for the pelvic AVMs, but the effect decreased with repetition and the patient died of heart failure 2 years after the first embolization. The serum levels of tissue plasminogen activator (t-PA), platelet-derived growth factor (PDGF), hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and transforming growth factor beta1 were high, suggesting that these angiogenic molecules may play a role in the pathogenesis of AVMs in Cowden disease. (+info)
Cultured endothelial cells from human arteriovenous malformations have defective growth regulation.
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Vascular malformations are frequent in newborns, and they persist throughout life, which differentiates them from vascular tumors (eg, hemangiomas). Arteriovenous malformations are high-flow vascular malformations. They are considered nonmalignant but can expand and become a significant clinical risk when extensive. To characterize endothelial cells from arteriovenous malformations (AMEC), we cultured cells obtained from surgical specimens and studied their properties. After selection, the cells that grew out from explants had phenotypic and antigenic features (platelet endothelial cell adhesion molecule, von Willebrand factor) of human endothelial cells. Their spontaneous proliferation rate was higher (1.8 to 6.4 times) than that of human umbilical vein, arterial, or microvascular endothelial cells. The proliferation rate of AMEC was not sensitive to the inhibitory activity of various cytokines (interleukin-1beta, tumor necrosis factor-alpha, transforming growth factor-beta, Interferon-gamma). In basal conditions, intercellular adhesion molecule (ICAM-1) was detected at a higher level of expression (6- to 10-fold) on AMEC, but these cells failed to express E-selectin or the vascular cell adhesion molecule (VCAM-1) after cytokine stimulation. Expression of c-ets-1 proto-oncogene was shown by in situ hybridization. The low response to cytokines, the higher propensity to proliferate, and the ets-1 expression suggest that AMEC have a defective regulation of proliferation that may be due to a reduced apoptotic process. (+info)