A review of extraaxial developmental venous anomalies of the brain involving dural venous flow or sinuses: persistent embryonic sinuses, sinus pericranii, venous varices or aneurysmal malformations, and enlarged emissary veins.

This paper is a narrative review of extraaxial developmental venous anomalies (eDVAs) of the brain involving dural venous flow or sinuses: persistent embryonic sinuses, sinus pericranii, enlarged emissary veins, and venous varices or aneurysmal malformations. The article highlights the natural history, anatomy, embryology, imaging, clinical implications, and neurosurgical significance of these lesions, which the authors believe represent a continuum, with different entities characterized by distinct embryopathologic features. The indications and surgical management options are discussed for these individual intracranial pathologies with relevant illustrations, and a novel classification is proposed for persistent falcine sinus (PFS). The role of neurointervention and/or microsurgery in specific cases such as sinus pericranii and enlarged emissary veins of the skull is highlighted. A better understanding of the pathophysiology and developmental anatomy of these lesions can reduce treatment morbidity and mortality. Some patients, including those with vein of Galen malformations (VOGMs), can present with the added systemic morbidity of a high-output cardiac failure. Although VOGM is the most studied and classified of the above-mentioned eDVAs, the authors believe that grouping the former with the other venous anomalies/abnormalities listed above would enable the clinician to convey the exact morphophysiological configuration of these lesions, predict their natural history with respect to evolving venous hypertension or stroke, and extrapolate invaluable insights from VOGM treatment to the treatment of other eDVAs. In recent years, many of these symptomatic venous malformations have been treated with endovascular interventions, although these techniques are still being refined. The authors highlight the broad concept of eDVAs and hope that this work will serve as a basis for future studies investigating the role of evolving focal venous hypertension/global intracranial hypertension and possibilities of fetal surgical intervention in these cases.

Sinus pericranii: diagnosis and management in 21 pediatric patients.

OBJECT: Sinus pericranii (SP) is a rare venous anomaly abnormally connecting the intracranial dural sinuses with the epicranial veins. In the present study the authors aimed to clarify this clinicoradiological entity, define the role of angiography in its preoperative assessment, and suggest a diagnostic-therapeutic flow chart for management purposes. METHODS: The authors retrospectively reviewed the clinical charts and neuroimages of 21 patients with SP. All patients underwent brain MRI, MR venography, and craniocerebral CT. Diagnostic digital subtraction angiography was performed in 19 of 21 patients, and the SPs were categorized as dominant (draining the majority of the intracranial venous outflow) or accessory (draining only a minority of the intracranial venous outflow). RESULTS: SP was median or paramedian in 20 patients and lateral in 1 patient. There were 5 dominant and 14 accessory SPs. The dominant SPs were not treated. Among the patients with accessory SP, 4 were not treated, 2 underwent surgical ligature, and 8 were treated endovascularly (with either transvenous or percutaneous embolization). No complications were observed, and symptoms disappeared after treatment in all cases. CONCLUSIONS: Accepted guidelines or recommendations concerning the management, diagnosis, and treatment of SP are still lacking. The authors define here a diagnostic-therapeutic flow chart, in which angiography plays a crucial role in the classification of SP and choice of the optimal treatment. Only accessory SP is amenable to treatment, whereas dominant SP must be preserved. The endovascular approach is becoming increasingly relevant and has proven to be safe and effective.