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PT  - JOURNAL ARTICLE
AU  - Dehkharghani, S.
AU  - Kang, J.
AU  - Saindane, A.M.
TI  - Improved Quality and Diagnostic Confidence Achieved by Use of Dose-Reduced Gadolinium Blood-Pool Agents for Time-Resolved Intracranial MR Angiography
AID  - 10.3174/ajnr.A3693
DP  - 2014 Mar 01
TA  - American Journal of Neuroradiology
PG  - 450--456
VI  - 35
IP  - 3
4099  - http://www.ajnr.org/content/35/3/450.short
4100  - http://www.ajnr.org/content/35/3/450.full
SO  - Am. J. Neuroradiol.2014 Mar 01; 35
AB  - BACKGROUND AND PURPOSE: Time-resolved MRA with the use of bolus injection of paramagnetic agents has proved valuable in neurovascular imaging. Standard contrast agents have limited blood-pool residence times, motivating the development of highly protein-bound blood-pool agents with greater relaxivity and longer intravascular residence, affording improved image quality at lesser doses. This study represents the first comparison of blood-pool agents to standard agents in time-resolved cerebral MRA. MATERIALS AND METHODS: One hundred datasets were acquired at 1.5T by use of a standardized, time-resolved MRA protocol. Patients received either unit dosing of a standard extracellular agent at 0.1 mmol/kg or a blood-pool agent at 0.03 mmol/kg. Peak arterial and venous enhancement phases were identified and subsequently scored qualitatively by use of a 4-point Likert scale, with attention to 6 vascular segments: 1) intracranial ICA; 2) MCA M1; 3) MCA M2; 4) MCA M3; 5) deep cerebral veins; and 6) dural venous sinuses. RESULTS: Fifty MR angiographies were acquired with each agent. No significant differences were found between agents in generation of uncontaminated arteriograms. Blood-pool agents, at 67% dose reduction, were of significantly greater quality across most vascular segments, including ICA (P = .019), M2 (P = .003), and M3 (P &amp;lt; .01). Superiority in the M1 segment approached significance (P = .059). Significantly better venographic quality was noted for deep venous structures (P = .016) with the use of blood-pool agents. CONCLUSIONS: Blood-pool agents provide superior demonstration of most intracranial vessels in time-resolved MRA compared with standard agents, at reduced doses. The greater relaxation enhancement and more favorable dosing profile make blood-pool agents superior to standard agents for use in cerebral time-resolved MRA. TR-MRAtime-resolved MRABPAblood-pool agentsSCAstandard contrast agentsDAVFdural arteriovenous malformation