R. Michael Scott and Edward R. Smith
Gyang Markus Bot, Jan-Karl Burkhardt, Nalin Gupta, and Michael T. Lawton
Revascularization is indicated in the management of moyamoya disease (MMD), with options that include direct and indirect techniques. Indirect bypass is popular in young children because the diminutive caliber of donors and recipients makes direct bypass difficult. The authors reviewed a series of patients treated with direct superficial temporal artery (STA)–to–middle cerebral artery (MCA) bypass in combination with encephalomyosynangiosis (EMS) in children 3 years or younger to demonstrate feasibility and safety.
A retrospective review of all surgeries for MMD over a 19-year period identified 11 procedures in 6 patients. Surgical results, angiographic outcomes, and clinical outcomes were analyzed.
Patients had a mean age of 22.4 months. The symptomatic hemisphere was revascularized first, and the contralateral hemisphere was revascularized on average 2.8 months later in 5 patients. All direct bypasses were patent postoperatively and remained patent at late follow-up (mean 4.1 years), with both STA and MCA diameters increasing significantly (n = 5, p < 0.03). At last follow-up (mean follow-up duration, 5.0 years), favorable outcomes (modified Rankin Scale scores 0–2) were observed in 5 of the 6 patients (83%), with 1 dependent patient remaining unchanged postoperatively.
Direct STA-MCA bypass in combination with EMS for MMD is feasible and safe in patients 3 years or younger, based on favorable clinical and radiological outcomes in this patient cohort. Direct bypass should be considered when immediate revascularization is needed, without the biological delay associated with indirect bypass.
W. Caleb Rutledge, Omar Choudhri, Brian P. Walcott, Arnau Benet, Christine K. Fox, Nalin Gupta, and Michael T. Lawton
Mutations in the smooth muscle–specific isoform of alpha actin (ACTA2) cause smooth muscle dysfunction in arteries. This rare loss-of-function mutation may cause a diffuse occlusive cerebral arteriopathy, resulting in stroke. While ACTA2 arteriopathy is often described as moyamoya-like, it has a distinct phenotype characterized by dilation of the proximal internal carotid artery (ICA) and occlusion of the terminal ICA and proximal middle cerebral artery. Intracranial arteries have an abnormally straight course, often with small aneurysms. There is limited experience with revascularization procedures for ACTA2 arteriopathy, and the safety and efficacy of these procedures are unknown. In this paper the authors present a symptomatic 6-year-old patient with ACTA2 cerebral arteriopathy who underwent both indirect revascularization and direct cerebrovascular bypass. Postoperatively, the patient suffered an ischemic infarct in a neighboring vascular territory. While direct cerebrovascular bypass is technically feasible, patients with ACTA2 arteriopathy may be at increased risk for perioperative stroke compared with patients with moyamoya disease.
James S. Waldron, Steven W. Hetts, Jennifer Armstrong-Wells, Christopher F. Dowd, Heather J. Fullerton, Nalin Gupta, and Michael T. Lawton
Microcephalic osteodysplastic primordial dwarfism type II (MOPD II) is a rare genetic syndrome characterized by extremely small stature and microcephaly, and is associated in 25% of patients with intracranial aneurysms and moyamoya disease. Although aneurysmal subarachnoid hemorrhage and stroke are leading causes of morbidity and death in these patients, MOPD II is rarely examined in the neurosurgical literature. The authors report their experience with 3 patients who presented with MOPD II, which includes a patient with 8 aneurysms (the most aneurysms reported in the literature), and the first report of a patient with both moyamoya disease and multiple aneurysms. The poor natural history of these lesions indicates aggressive microsurgical and/or endovascular therapy. Microsurgery, whether for aneurysm clip placement or extracranial-intracranial bypass, is challenging due to tight surgical corridors and diminutive arteries in these patients, but is technically feasible and strongly indicated when multiple aneurysms must be treated or cerebral revascularization is needed.
Nader Sanai, Heather Fullerton, Tom R. Karl, and Michael T. Lawton
✓ Large-vessel vasculitis syndromes in the pediatric population are rare and highly morbid. The authors here report on the microsurgical revascularization of a unique case of presumed vasculitis with aortitis and severe obliterative arteriopathy in a 10-month-old child with symptomatic hemispheric hypoperfusion. Using a cryopreserved saphenous vein, this unilateral aortocarotid bypass restored normal intracranial perfusion bilaterally and led to a resolution of the patient's ischemic symptoms. The aortocarotid bypass is clinically effective and technically feasible in young children when a saphenous vein allograft is used. The bypass graft is amenable to angioplasty with or without stenting if delayed stenosis becomes an issue later in life.