Magnetic resonance imaging findings of developmental venous anomalies.

PURPOSE

This study evaluated morphological features of developmental venous anomalies (DVAs) based on magnetic resonance imaging (MRI) findings. The study also evaluated the factors affecting the visibility of DVAs on MRI.

METHODS

We reviewed contrast-enhanced MRIs of 75 patients with DVA. The images were selected from 1,165 consecutive cranial MRIs. The images were examined for the DVA location, the number of collecting veins, the collecting vein diameter, drainage veins and sinuses, any accompanying parenchymal abnormalities or lesions, and the DVA visibility on MRI.

RESULTS

DVAs prevalence was determined as 6.4 %. A total of 88 DVAs were observed. Single DVAs were observed in 65 patients, two were observed in 7 patients and three were observed in 3 patients. The DVA caputs had deep localization most frequently in 54.5 % of patients. A total of 98 collecting veins were identified, with a single vein identified in 80 DVAs. A statistically significant difference (p = 0.000) was found in the diameter of the collecting veins between DVAs that were the visible and nonvisible on noncontrast MRI.

CONCLUSIONS

Most frequently, a single DVA was observed in the patients. A DVA caput could be located in the deep, subcortical, juxtacortical or deep + subcortical and juxtacortical + subcortical regions. Increasing collecting vein diameter increased visibility on noncontrast MRI, and small DVAs could be overlooked, even with contrast-enhanced MRI series if the images were not examined carefully.