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cerebral_arteriovenous_malformation

Cerebral arteriovenous malformation (AVM)

Intracranial arteriovenous malformation in the brain.

As brain arteriovenous malformations (AVMs) are highflow vascular abnormalities, increased CBF can be identified inside the nidus or draining veins.

Up-regulated VEGF in part of brain and Tie-2, Angiopoietin 2 high expression in endothelial cells (EC) of some vessels may be one of major factors for cerebral arteriovenous malformation (CAVM) formation growth, and rupture in the embryonic period 1).

Epidemiology

Types

Grading

Numerous classification schemes have been developed, each with its own emphasis, accuracy, advantages, and disadvantages 2) 3) 4) 5) 6) 7).

The Spetzler-Martin AVM grading system is the most widely used grading system for AVMs.

see also Supplementary Spetzler-Martin AVM grading scale.

see Spetzler Ponce classification.

Clinical Features

Intracranial hemorrhage

Epilepsy

Epilepsy is the second most common symptom in cerebral arteriovenous malformation (AVM) patients.

Patients presenting with AVM-associated epilepsy have a favorable seizure outcome after surgical treatment. Long-standing epilepsy and the progress into drug-resistant epilepsy (DRE) markedly deteriorate the chances to obtain seizure freedom and should be considered an early factor in establishing the indication for AVM removal 8).

Epileptic seizures are a common presenting symptom of arteriovenous malformations (AVMs). However, the impact of treatment modality on seizure control remains unclear.

In 164 patients, 31 patients (20.7%) had Spetzler-Martin grade I AVMs, 51 (34.0%) grade II, 47 (31.3%) grade III, 20 (13.3%) grade IV, and 1 (0.7%) grade V. Of the 49 patients (30%) presenting with seizures, 60.4% experienced seizure persistence after treatment. For these patients, radiosurgery was associated with seizure recurrence (odds ratio: 4.32, 95% confidence interval: 1.24-15.02, P = .021). AVM obliteration was predictive of seizure freedom at last follow-up (P = .002). In contrast, for patients presenting without seizures, 18.4% experienced de novo seizures after treatment, for which surgical resection was identified as an independent risk factor (hazard ratio: 8.65, 95% confidence interval: 3.05-24.5, P < .001).

This data suggest that achieving seizure freedom should not be the primary goal of AVM treatment, surgical resection may result in improved seizure control compared with radiosurgery for patients who present with seizures. Conversely, in patients without presenting seizures, surgical resection increases the risk of new-onset seizures compared with radiosurgery, but primarily within the early posttreatment period. Surgical resection and radiosurgery result in divergent seizure control rates depending on seizure presentation 9).

Differential diagnosis

Primary lobar hemorrhages (usually due to cerebral amyloid angiopathy) are typically seen in elderly. Younger patients may also develop lobar haemorrhages, but in such cases they usually have an underlying lesion (e.g. cerebral arteriovenous malformation).

Complications

The most devastating complication of cerebral AVMs is rupture of the nidi resulting in intracerebral hemorrhage. With increasing long-term natural history studies available.

They are of special concern because of the damage they cause when they bleed.

see Cerebral arteriovenous malformation recurrence

Complication-Effectiveness Analysis

Seven hundred seventy-nine patients underwent 641 microsurgical resections. Complications of surgery leading to a modified Rankin Scale >1 at 12 months occurred in 1.4% (95% confidence interval [CI]: 0.5-3.3), 20% (95% CI: 15-26), and 41% (95% CI: 30-52) of Spetzler-Ponce class A, SPC B, and SPC C, respectively. The cumulative 9-year freedom from recurrence was 97% for SPC A and 92% for other cAVMs. The 9-year CEA risk was 1.4% (credible range: 0.5%-3.4%) for SPC A, 22% to 24% (credible range: 16%-31%) for SPC B, and 45% to 63% (credible range: 33%-73%) for SPC C bAVM.

CEA presents the treatment outcome in the context of efficacy and provides a basis for comparing outcomes from techniques with different times to elimination of the bAVM 10).

Treatment

Case series

1)
Li J, Gao Y, Zhao M. [Immunohistochemical study of vascular endothelial growth factor, relative receptors and ligands in vascular endothelial cells of cerebral arteriovenous malformation]. Zhonghua Wai Ke Za Zhi. 2001 Sep;39(9):675-8. Chinese. PubMed PMID: 11769600.
2)
Davies JM, Kim H, Young WL, Lawton MT. Classification schemes for arteriovenous malformations. Neurosurg Clin N Am. 2012;23(1):43–53.
3)
Griessenauer CJ, Miller JH, Agee BS, et al.. Observer reliability of arteriovenous malformations grading scales using current imaging modalities. J Neurosurgery. 2014;120(5):1179–1187.
4)
Hollerhage HG, Dewenter KM, Dietz H. Grading of supratentorial arteriovenous malformations on the basis of multivariate analysis of prognostic factors. Acta Neurochir (Wien). 1992;117(3-4):129–134.
5)
Pertuiset B, Ancri D, Kinuta Y, et al.. Classification of supratentorial arteriovenous malformations: a score system for evaluation of operability and surgical strategy based on an analysis of 66 cases. Acta Neurochir (Wien). 1991;110(1-2):6–16.
6)
Spears J, Terbrugge KG, Moosavian M, et al.. A discriminative prediction model of neurological outcome for patients undergoing surgery of brain arteriovenous malformations. Stroke. 2006;37(6):1457–1464.
7)
Tamaki N, Ehara K, Lin TK, et al.. Cerebral arteriovenous malformations: factors influencing the surgical difficulty and outcome. Neurosurgery. 1991;29(6):856–861; discussion 861-863.
8)
von der Brelie C, Simon M, Esche J, Schramm J, Boström A. Seizure Outcomes in Patients With Surgically Treated Cerebral Arteriovenous Malformations. Neurosurgery. 2015 Jul 29. [Epub ahead of print] PubMed PMID: 26225856.
9)
Wang JY, Yang W, Ye X, Rigamonti D, Coon AL, Tamargo RJ, Huang J. Impact on seizure control of surgical resection or radiosurgery for cerebral arteriovenous malformations. Neurosurgery. 2013 Oct;73(4):648-55; discussion 655-6. doi: 10.1227/NEU.0000000000000071. PubMed PMID: 23842554.
10)
Morgan MK, Wiedmann M, Assaad NN, Heller GZ. Complication-Effectiveness Analysis for Brain Arteriovenous Malformation Surgery: A Prospective Cohort Study. Neurosurgery. 2015 Nov 24. [Epub ahead of print] PubMed PMID: 26606671.
cerebral_arteriovenous_malformation.txt · Last modified: 2019/05/02 20:40 by administrador