[Validation of a new hand-carried ultrasound device equipped with directional color power Doppler and continuous wave Doppler].
OBJECTIVE
This study evaluated the accuracy of the directional color power Doppler (DCPD) and continuous wave Doppler (CWD) methods incorporated in the new hand-carried SonoSite 180PLUS ultrasound device.


METHODS
The hand-held ultrasound system with 2.5 MHz transducer and SONOS 5500 was used as a standard ultrasound system with a 2 to 4 MHz wideband transducer. The experimental study used a Doppler wire phantom to evaluate the influence of target wire speed and angle of transducer on DCPD imaging. The clinical study included 48 consecutive patients. DCPD assessment of valvular regurgitation measured the distances of DCPD signals of mitral, aortic and tricuspid valve regurgitation using the apical four-chamber view for comparison with standard echocardiography. CWD assessment measured the peak velocities of the aortic flow and tricuspid valve regurgitant flow for comparison with standard echocardiography.


RESULTS
In the experimental study, DCPD signals were not influenced by target wire speed changes and transducer incident angles. In the clinical study, agreements for mitral, aortic and tricuspid regurgitation between the two methods were 89.6%, 81.8% and 78.7%, respectively. The distances of DCPD valve regurgitant signals by the hand-carried ultrasound device showed good correlation (mitral regurgitation: y = 0.84x + 0.55; r = 0.93, aortic regurgitation: y = 0.95x + 0.27; r = 0.94, tricuspid regurgitation: y = 0.86x + 0.61; r = 0.90) with those by standard echocardiography. Evaluation of CWD velocity measurements showed good agreement for the lower flow velocities (< 2.0 m/sec). However, underestimation occurred for the high flow velocities (> 2.0 m/sec) compared with those by standard echocardiography (aortic flow: y = 0.80x + 0.11; r = 0.95, tricuspid regurgitation: y = 1.00x - 0.23; r = 0.90).


CONCLUSIONS
The new hand-carried ultrasound device (SonoSite 180PLUS equipped with DCPD and CWD) is clinically useful for evaluating valvular regurgitations and flow velocities. Further studies are needed to determine the mechanism of the underestimation of high flow velocities by CWD.
Kawai
Junichi
J
Division of Clinical Laboratory, Kobe General Hospital, Minatojima, Naka-machi 4-6, Chuo-ku, Kobe 650-0046.
Tanabe
Kazuaki
K
Matsuzaki
Masashi
M
Yamaguchi
Kazuto
K
Yagi
Toshikazu
T
Fujii
Yoko
Y
Konda
Toshiko
T
Ui
Kazuyo
K
Sumida
Toshiaki
T
Okada
Midori
M
Tani
Tomoko
T
Morioka
Shigefumi
S
D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging; D006349:Heart Valve Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D012680:Sensitivity and Specificity; D014159:Transducers; D014262:Tricuspid Valve Insufficiency / Q000000981:diagnostic imaging; D018608:Ultrasonography, Doppler / Q000295:instrumentation* / Q000592:standards; D018615:Ultrasonography, Doppler, Color / Q000295:instrumentation* / Q000592:standards