Time-resolved MR angiography of the intracranial venous system: an alternative MR venography technique.

OBJECTIVES

To compare time-resolved imaging of contrast kinetics (TRICKS) magnetic resonance angiography (MRA) with two-dimensional time-of-flight (TOF) magnetic resonance venography (MRV), and three-dimensional contrast-enhanced (CE) MRV in the visualisation of normal cerebral veins and dural venous sinuses.

METHODS

This prospective study consisted of 35 consecutive patients. All patients were examined with TOF MRV, TRICKS MRA and CE MRV; a single dose of intravenous contrast material was administered for the last two sequences. The image quality of these techniques was assessed and compared qualitatively (by a semiquantitative scoring system) and quantitatively (by calculating signal-to-noise ratios [SNRs] and contrast-to-noise ratios [CNRs]).

RESULTS

Left transverse sinus, left sigmoid sinus, bilateral thalamostriate veins and Trolard veins were better visualised by TRICKS MRA and CE MRV compared with TOF MRV (P < 0.05). For left thalamostriate vein visualisation, TRICKS MRA was inferior to CE MRV (P < 0.05). With quantitative analysis the SNRs and CNRs were highest at TRICKS MRA, which was followed by CE MRV and TOF MRV (P < 0.05).

CONCLUSIONS

Despite its limited spatial resolution, TRICKS MRA is comparable to static CE MRV and better than TOF MRV in the visualisation of normal dural sinuses and cerebral veins.

KEY POINTS

• Time resolved magnetic resonance angiography can image the intracranial venous system dynamically • It seems comparable to contrast-enhanced MRV techniques in venous visualisation • The optimal phase for venous structures can be chosen from the dynamic data set • The diagnostic performance in venous thrombosis requires further research.