Vein of Galen aneurysmal malformations: critical analysis of the literature with proposal of a new classification system

Abstract

<jats:p>Vein of Galen aneurysmal malformations are a rare and diverse group of entities with a complex anatomy, pathophysiology, and serious clinical sequelae. Due to their complexity, there is no uniform treatment paradigm. Furthermore, treatment itself entails the risk of serious complication. Offering the best treatment option is dependent on an understanding of the aberrant anatomy and pathophysiology of these entities, and tailored therapy is recommended. Herein, the authors review the current concepts related to vein of Galen aneurysmal malformations and suggest a new classification system excluding mesodiencephalic plexiform intrinsic arteriovenous malformations from this group of malformations.</jats:p>

Are parenchymal AVMs congenital lesions?

“…11 However, prenatal diagnosis of a parenchymal AVM is exceedingly rare, 5,10,13 which is in contrast to other vascular lesions (for example, vein of Galen aneurysmal malformations) that are frequently detected in utero or shortly after birth. 26 Furthermore, the number of AVMs diagnosed in the neonatal period is also limited, 30 and it is estimated that only 1% of AVMs are diagnosed during the first 2 years of life. These facts further bring into question the assumption that AVMs develop early during embryonic development and are present at birth.…”

Galen Vein Thrombosis With Bilateral Thalamus Infarction

“…Patients get referred to a neurologist after interventions and different care modalities. Even though partial flow disturbance in the course of Galen vein has somehow contributed to the course of the disease, perhaps, it has not been the main causative element (7)(8)(9). Changes shown by the white arrows in the magnetic resonance venography (MRV) (Figure 2) could also be due to a stenosis, duplication, or fenestration rather than thrombus formation; but, response to the treatment highlighted the possibility of thrombosis.…”

Galenic pial arteriovenous fistulas: Angioarchitecture, clinical presentation, and therapeutic considerations

“…[Figure and legend modified with permission from Figs. 5 to 10 of (Mortazavi et al, J Neurosurg Pediatr, , 12, 293–306)]. [Color figure can be viewed at http://wileyonlinelibrary.com]…”

“…High flow through the fistula maintains the patency of the falcine sinus and forestalls normal straight sinus venogenesis (Raybaud et al, ). In the event of spontaneous or therapeutic thrombosis of the Galenic drainage, alternative venous drainage pathways including the subtemporal, thalamic, and lateral mesencephalic veins, and persistent and accessory falcine sinuses, can provide collateral outflow (Morgan et al, ; Mortazavi et al, ). Telencephalic and diencephalic drainage can be shunted to the basal veins of Rosenthal (via striate veins) and tentorial sinuses, respectively (Lasjaunias et al, ).…”