Editorial: Vein of Galen malformation

Before the development of modern endovascular techniques, vein of Galen aneurysmal malformations (VGAMs) carried a dismal prognosis. A 100% mortality rate for surgical treatment was almost uniformly reported in early series.2 Modern treatment strategies have changed the outlook of this condition with survival rates approaching 80% in treated patients. This improvement is largely due to endovascular treatment coupled with advancements in (antenatal) diagnostic opportunities, improvements in perinatal intensive care management, and an overall multimodality teamwork approach. In this issue of the Journal of Neurosurgery: Pediatrics, Li and coworkers4 report their 21-year experience with this challenging but uncommon condition. Of 26 patients evaluated over this time interval, 21 received endovascular treatment and constitute the focus of their report. Their treatment strategy is modeled after the guidelines established by Lasjaunias and coworkers.3 In neonates presenting in distress due to cardiocirculatory compromise, the goal is to decrease hemodynamic stress through partial transarterial embolization while deferring definitive treatment until the patient is older. Treatment should not be pursued in neonates with severe compromise of the brain parenchyma or in those with associated severe systemic conditions. With an improved mortality rate, more emphasis is placed on the functional outcome of these children and their neurological development. Significant developmental delay has been reported in 16%–40% of patients.1 In 1 report, developmental delay was associated with the pathoanatomical variation of the choroidal type and presentation with congestive heart failure.2 No such association was noted in the present series.4 Although the therapeutic strategy of the Toronto group has been to delay treatment in stable infants, the authors’ data may suggest that early treatment is associated with better psychomotor development. However, this observation may be a mere consequence of the strategy of pursuing treatment past the neonatal stage only after the development of hydrocephalus or failure to achieve neurodevelopmental milestones. It is possible that once brain development has been compromised by the VGAM hemodynamics, such developmental changes cannot be reversed even after successful treatment of the underlying lesion. Further investigations should focus on possible predictors of developmental alterations so that earlier treatment can be offered to these at-risk patients. I wonder if the authors of this report have any insight into possible angioarchitecture, hemodynamic, or imaging characteristics predictive of a worse neurological outcome. Despite overall improved outcomes, VGAMs continue to represent a formidable challenge. Arterial access can be difficult, and the amount of contrast that can be safely administered is limited by the small size and the often compromised or borderline renal function. The transarterial approach used here (and previously described by Lasjaunias and colleagues3 in detail) with highly concentrated glue is technically demanding. Moreover, endovascular procedures in these neonates are performed in conditions of extreme distress. The complexities of endovascular treatment also extend to the entire team treating these patients, including pediatric intensivists, anesthesiologists, cardiologists, neurologists, and neurosurgeons. In the present series, 2 of 7 neonates died during treatment. These challenges and the rarity of this condition suggest that, ideally, its treatment should be limited to a few regional centers. The incredible experience of Lasjaunias and colleagues3 at the Hopital de Bicetre, with more than 216 cases treated at their institution, demonstrates this to be possible even in a disease with such a level of acuity.