Purpose : To verify the hypothesis that a drug that causes vasodilatat
ion can contribute to improvement in MRA spatial resolution. To test t
his hypothesis, a comparison was made between the images obtained usin
g the high resolution time-of-flight (TOF HR 3D) technique and the TOF
3D MTC TONE technique. Methods: From November 1993 to December 1994,
we studied 40 patients, of which 20 patients (16 males and 4 females;
agerage age of 10 years; range from 3 to 20 years) we examined after t
hey had inhaled Isoflurane (experimental group), and 20 patients (16 m
ales and 4 females; average age 9.7 years; range from 3 to 12 years) w
ere examined with standard MRA (control group). Results: The vasodilat
or in both HR MRA and MTC TONE MRA permits a better spatial visualizat
ion with respect to the clinical routine MRA. On the other hand, it is
true that MTC TONE gives better visualization of the small vessels Di
scussion : In our experience, this preliminary study indicates that wi
th respect to routine MR, the spatial resolution is notably increased
when Isoflurane is used. The signal-to-noise ratio is increased but, m
oreover, the ability to visualize small vessels is increased. Conclusi
on : The preliminary results obtained in this study indicate that a ph
armacological drugs is capable of increasing the vascular detail of MR
A images of the intracranial vessels and that continued research this
direction is called for.