K. Rosenkranz et al., CONTRAST-ENHANCED TRANSCRANIAL DOPPLER US WITH A NEW TRANSPULMONARY ECHO CONTRAST AGENT BASED ON SACCHARIDE MICROPARTICLES, Radiology, 187(2), 1993, pp. 439-443
The purpose of this first patient study (phase II) was to evaluate the
clinical usefulness of a new echo contrast agent at transcranial Dopp
ler ultrasonography (US). Twenty patients were selected from a group o
f 242 patients undergoing conventional transcranial Doppler US who had
low (n = 18) or absent (n = 2) Doppler signals from the middle cerebr
al artery (MCA). The extent and duration of Doppler signal increase wa
s measured in 30 MCAs and in 14 basilar arteries following the intrave
nous injection of a transpulmonary galactose microparticle suspension
(SH U 508 A) at three concentrations (200, 300, and 400 mg/mL). Dopple
r waveform analysis became possible in 93% (28 of 30) of the MCAs foll
owing injection. The maximal increase in average Doppler signal intens
ity (11 dB at 200 mg/mL, 15 dB at 300 mg/mL, and 17 dB at 400 mg/mL) a
nd the increase in average duration of the signal enhancement (163 sec
onds at 200 mg/mL, 219 seconds at 300 mg/mL, and 240 seconds at 400 mg
/mL) depended on contrast agent concentration. Doppler waveform analys
is became possible in 79% (11 of 14) of the basilar arteries. The intr
avenous injection of this new echo contrast agent markedly increases D
oppler signal intensity in patients with nondiagnostic results at conv
entional Doppler US.