Article

We review, in the light of the recent literature, the modalities
and indications of surgical cerebral revascularization for Moyamoya (MM) disease
or syndrome. We also report our experience in the surgical management of adult
MM. In symptomatic forms, with presence of severe disturbances of perfusion or
cerebrovascular reactivity on multimodal imaging work-up, the risks of recurrent
ischemic or hemorrhagic stroke is high (respectively 10-13%/yr and 2-7%/yr). The
objective of treatment is to augment cerebral perfusion (in ischemic forms) or to
reduce lenticulo-striate neovessel overload (in hemorrhagic forms), by initiating
the development of a cortical neovascularization and/or by directly increasing
cerebral blood flow. The risk of immediate postoperative death or stroke is
similar between indirect and direct or combined techniques and respectively
0-0.5% and 3-6%, provided a strict perioperative anesthetic management is applied
(normocapnia, normoxia and controlled hypertension). Indirect techniques (i.e.
encephalo-duro-arterio-myo-periosteo-synangiosis or multiple burr-holes) are
technically easy, allow wide cortical revascularization and are very efficient in
children: absence of clinical recurrence in more than 95% of cases and presence
of a good neovascularization in 83%. However, their effect is delayed for several
months, the impact on the hemorrhagic risk is moderate and the global response is
uncertain in adults. Direct (superficial temporal artery to middle cerebral
artery bypass) or combined techniques improve cerebral blood flow immediately and
significantly. They are associated with a higher rate of stroke-free survival at
5 years (95% vs 85%). A recent randomized study has proven that they could reduce
the hemorrhagic risk by 2- to 3-fold in comparison with conservative treatment
alone. However, their feasibility in children is limited by the very small size
of vessels. We present also our results in the surgical management of 12 adult MM
patients (mean age 41.3, sex ratio=1) operated between 2009 and 2014 (14
revascularization procedures: EDAMS 2, multiple burr-holes 1, combined
revascularization procedures 11). MM types according to clinical presentation
were the following: ischemic 8, hemorrhagic 2, combined 2. All patients were
recently symptomatic, with recurrent ischemic/hemorrhagic events (2/3) or
crescendo neurological deficit (1/3) in association with severe alterations of
cerebral blood flow. Mean clinical and radiological follow-up was 22 months.
Postoperative mRS at 6 months was improved or stable in 92%. None of the patients
suffered recurring stroke. In conclusion, surgical treatment should be discussed
quickly in symptomatic forms of MM (progressive or recurring) because of their
poor outcome. Indirect techniques are favored in pediatric patients due to their
simplicity and good clinical results. Direct, or preferentially combined
techniques would be more effective in adult patients to prevent the recurrence of
ischemic or hemorrhagic stroke.
CI - Copyright (c) 2014 Elsevier Masson SAS. All rights reserved.

Langue : ANGLAIS