Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

Abstract

Introduction: Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies.

Methods: CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console.

Results: Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv.

Conclusion: Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures.

Fig. 1

Three ROIs measuring 8 mm in diameter and 0.5 mm thickness were placed 3 mm apart in a triangular pattern within the affected hemisphere and mirrored in the unaffected hemisphere (case 1 in the upper row; a, b, c). An identical ROI template was used for each control (control 1 in lower row d, e, f) to facilitate comparisons of absolute values and relative CTP percentages for regional CBV (a, d), regional CBF (b, e), and MTT (c, f)

Fig. 2

Box plots of absolute hemispheric values for three ROIs of CBV, CBF, and MTT for each case and control group included: a case-affected hemisphere versus case-unaffected hemisphere, b control-matched affected versus control-matched hemisphere unaffected, (c) case-affected versus control affected, and (d) case-unaffected versus control unaffected. Outlier values (asterisk) are depicted in the CTP parameter group as applicable. Significant p values are listed in the upper right corners and near statistical significance is preceded by a pound sign

Fig. 3

Volumetric surface CT perfusion maps from case 2 of cortical changes (arrows) in regional CBV (a), regional CBF (b), and MTT (c) related to a left frontal juxtacortical DVA with a superficial collecting vein

Fig. 4

(a) A 64-year-old male with a subcortical right cerebellar hemisphere DVA on the right side (case 3) on axial DSA. Increased CTP values are present in the affected hemisphere (arrows) for regional CBV (b), regional CBF (e), and MTT (f) relative to the unaffected hemisphere. No significant differential TTP values were present (c). Orthogonally edited CTA-V view of the venous system, demonstrating the cerebellar hemisphere DVA on the right side with dilated intramedullary veins that converge into a collecting vein that enters the lateral aspect of the right transverse venous sinus is demonstrated (d)

Fig. 5

A 50-year-old female who presented with numbness on the right side of her face (case 1); a juxtacortical left frontal lobe DVA was identified. a Upper left axial image is a DSA image collected with slice thickness of 30 mm and then clockwise from left to right axial perfusion images are colorimetric representations of b regional CBV, c TTP, d regional CBF, e MTT, and f delay