Les cavernomes du système nerveux central. Historique et évolution des idées

Cavernous angiomas of the lateral ventricles

BACKGROUND

Cavernous angiomas are vascular malformations which rarely involve the cavities of the lateral ventricles. Knowledge of the specific clinical and neuroradiological features displayed by these lesions is limited by the scarcity of patients included in the reported series.

OBJECTIVE AND METHODS

The aim of this study was to compile and analyse the epidemiological, clinical, neuroradiological and surgical characteristics of these lesions as provided by the well-described examples reported in the scientific literature. A total of 49 were gathered, including three patients operated on recently in our Department.

FINDINGS AND CONCLUSIONS

Cavernomas developing within the ventricular cavities attain a larger size than parenchymal counterpart lesions, causing symptoms and signs derived mainly from the mass effect. The characteristic parenchymal hypointense rim is less frequently identified on T2-weighted echo-gradient MRI sequences. Total surgical excision is the treatment of choice for these lesions, yet the surgical routes employed may still be associated with a high rate of neurological complications.

Pathomechanisms of Symptomatic Developmental Venous Anomalies

Background and Purpose— Although it is generally accepted that developmental venous anomalies (DVAs) are benign vascular malformations, over the past years, we have seen patients with symptomatic DVAs. Therefore, we performed a retrospective study and a literature study to review how, when, and why DVAs can become clinically significant.

Methods— Charts and angiographic films of 17 patients with DVAs whose 18 vascular symptoms could be attributed to a DVA were selected from a neurovascular databank of our hospital. MRI had to be available to rule out any other associated disease. In the literature, 51 cases of well-documented symptomatic DVAs were found. Pathomechanisms were divided into mechanical and flow-related causes.

Results— Mechanical (obstructive or compressive) pathomechanisms accounted for 14 of 69 symptomatic patients resulting in hydrocephalus or nerve compression syndromes. Flow-related pathomechanisms (49 of 69 patients) could be subdivided into complications resulting from an increase of flow into the DVA (owing to an arteriovenous shunt using the DVA as the drainage route; n=19) or a decrease of outflow (n=26) or a remote shunt with increased venous pressure (n=4) leading to symptoms of venous congestion. In 6 cases, no specific pathomechanisms were detected.

Conclusions— Although DVAs should be considered benign, under rare circumstances, they can be symptomatic. DVAs, as extreme variations of normal venous drainage, may represent a more fragile venous drainage system that can be more easily affected by in- and outflow alterations. The integrity of the DVA needs to be preserved irrespective of the treatment that should be tailored to the specific pathomechanism.