Radiographic and statistical analysis of Brain Arteriovenous Malformations. Poster No.: C-0996 Congress: ECR 2017 Type: Educational Exhibit Authors: C. E. Rodriguez 1, A. Lopez Moreno 1, D. Sánchez Paré 1, M. Keywords: DOI: Trinidad Ruiz 1, L. Fernández de Alarcón 1, C. Pascual Montero 2, S. Lojo Lendoiro 3 ; 1 Badajoz/ES, 2 Cáceres. Hospital San Pedro de Alcántara/ES, 3 Mérida, Badajoz/ES Neuroradiology brain, Catheter arteriography, Angioscopy, Arteriovenous malformations 10.1594/ecr2017/C-0996 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. www.myesr.org Page 1 of 17
Learning objectives Review the main characteristics of cerebral arteriovenous malformations through cases diagnosed and treated in our hospital. Page 2 of 17
Background Arteriovenous malformations (AVM) are conglomerates of anomalous arteries and veins, with direct communication, without capillaries or cerebral parenchyma between them. They are characterized by a nest that forms the transition between the feeding artery and the drainage vein. If this transition is performed directly, we are faced with a fistula. They are usually diagnosed between the second and fourth decade of life. They have no predilection for genders. They are usually isolated lesions in most cases, but are sometimes associated with different syndromes, including Rendu-Osler-Weber syndrome or hereditary hemorrhagic teleangiectasia. They affect approximately 4% of the population, being symptomatic only 12% of them. Of all cerebrovascular malformations, they are the ones that most often produce symptoms. These include headache and seizures (20% of cases), without presenting a specific pattern. The greatest danger of AVM is bleeding. The origin of AVMs is believed to be due to dysregulation of vascular endothelial growth factor (VEGF-1), although it remains unclear. Regarding their location, AVM can be: Supratentorial: 85%. Within these: Superficial: two-thirds Deep: one third Infratentorial: 15% AVMs can be classified in two according to the type of nest: Compact or glomerular nest (classic): abnormal vessels without healthy brain parenchyma interposed Page 3 of 17
Diffuse or proliferative nests: functional neuronal tissue intercalated between anomalous vessels. The Spetzler-Martin classification system rates between 1 and 5 AVMs, correlating this score with the surgical result. Grade 6 is used for inoperable lesions. A) Size of the nest: Small (<3 cm) = 1 Medium (3-6cm) = 2 Large (> 6 cm) = 3 B) Eloquent zone of the brain*: Not eloquent = 0 Eloquent = 1 C) Venous drainage: Superficial = 0 Deep = 1 *Eloquent areas of the brain: Sensoriomotor, language, visual cortex, hypothalamus, thalamus, brainstem, cerebellum nuclei, or regions directly adjacent to these structures Non-eloquent areas of the brain Frontal and temporal lobes, cerebellar hemispheres. Fig. 1 DIAGNOSIS Page 4 of 17
Computed Tomography (CT) They appear as serpiginous structures, calcified up to 30% of cases, which enhance after the administration of intravenous contrast, acquiring appearance in "bag of worms". They may be difficult to diagnose on CT without contrast, although they are often hyperdensed compared to the adjacent cerebral parenchyma. They do not usually cause mass effect, even the larger ones, unless they bleed. It is sometimes difficult to define the anatomy and vessels for feeding and drainage, so it will be necessary to perform an angiography. Fig. 2 Magnetic Resonance Imaging (MRI) Depending on the characteristics of the flow and the sequences acquired, they can present a variable appearance, being typical the morphology "in honeycomb". In T2- weighted sequences, the rapid flow generates signal gaps. MRI is also useful for diagnosing complications such as adjacent hemorrhage and edema. Fig. 3 Angiography The reference technique for the diagnosis of AVM continues to be digital subtraction angiography, especially the sequences performed with selective contrast injection. With it it is possible to diagnose the arteries on which it depends, the drainage pattern, as well as to describe a precise location of the lesion. Fig. 4 TREATMENT Treatment options and complication rates are dictated by the Spetzler rating. In general, the three options available are: endovascular occlusion, surgical resection and radiosurgery. Sometimes, in the context of intracranial hemorrhage and, due to venous compression and thrombosis, they have resolved spontaneously. Page 5 of 17
The annual risk of bleeding for untreated AVM is approximately 3%. If the patient suffers a hemorrhage, the risk of a recurrence in one year increases to 18%. Page 6 of 17
Images for this section: Fig. 1: Spetzler-Martin clasificacion - Badajoz/ES Page 7 of 17
Fig. 2: Image of an arteriovenous malformation on CT - Badajoz/ES Page 8 of 17
Fig. 3: Arteriovenous malformation seen in T2-weighted enhanced MRI - Badajoz/ES Page 9 of 17
Fig. 4: Sequence of images of the diagnosis of an arteriovenous malformation by arteriography. - Badajoz/ES Page 10 of 17
Findings and procedure details We analyzed data from 80 patients diagnosed and treated in our hospital, studying and classifying them according to age, clinical presentation, size, location, and the treatment they received. Then, we check the main characteristics of cerebral arteriovenous malformations (AVM) through these cases. The results obtained were as follows: 1. The mean age of the patients was 38 years, the median was 40 and mode, 50 years. 2. The youngest patient diagnosed with arteriovenous malformation was 7 years old, and the oldest, 83. 3. In almost all patients (80%) the initial diagnostic test was the CT. One patient needs CT and MRI, and other conventional arteriography (CA) for diagnosis. 4. The most frequent initial symptom was headache (47,5%), followed by hemiparesis and loss of consciousness, both in 18.8% of patients. 5. In most of cases (72,4%) the size was less than 3 cm. 6. 55% of the patients debuted with hemorrhage. 7. All the patients had a single arteriovenous malformation. 8. 87,34% of the malformations had a supratentorial location. 9. Embolization was the most frequent treatment (34,7%), followed closely by radiosurgery (32%). 10. Most patients had no associated abnormalities (70%). Of those who did, most had an aneurysm (19% of all patients). Fig. 5-8 Page 11 of 17
Images for this section: Fig. 5: Statistical analysis of the results. Symptom. - Badajoz/ES Page 12 of 17
Fig. 6: Statistical analysis of the results. - Badajoz/ES Page 13 of 17
Fig. 7: Statistical analysis of the results. Malformation size and Associated anomalies. - Badajoz/ES Page 14 of 17
Fig. 8: Statistical analysis of the results. Treatment. - Badajoz/ES Page 15 of 17
Conclusion With the analysis of the data obtained from patients from our hospital, we confirmed the main findings in cerebral arteriovenous malformations. The role of radiologist will be key in the diagnosis and management of vascular malformations. It is fundamental to know the characteristics findings in different imaging tests. Page 16 of 17
References Yamada S. Arteriovenous malformations in functional areas of the brain. Wiley-Blackwell. (1999) ISBN:0879934247 Lawton MT. Brain arteriovenous malformations. Nature Reviews Disease Primers. 10.1038/nrdp.2015.8 Sasikhan Geibprasert. Radiologic Assessment of Brain Arteriovenous Malformations: What Clinicians Need to Know. RadioGraphics. Mar 2010, Vol. 30: 483-501, 10.1148/ rg.302095728 Vilalta J. Malformaciones arteriovenosas cerebrales: experiencia personal con 121 pacientes tratados con microcirugía. Rev Neurol. 2015; 61: 481-9 Spetzler RF, Martin NA. A proposed grading system for arteriovenous malformations. J. Neurosurg. 1986;65 (4): 476-83. Page 17 of 17