R. Strelitzki et al., ULTRASONIC MEASUREMENT - AN EVALUATION OF 3 HEEL BONE SCANNERS COMPARED WITH A BENCH-TOP SYSTEM, Osteoporosis international, 6(6), 1996, pp. 471-479
Three commercial ultrasound bone scanners designed for os calcis measu
rements (Lunar Achilles, C.U.B.A. ''Research'' and UBA 575) were compa
red using the Leeds Ultrasonic Bone Phantoms. The porosity of the phan
toms ranged from 50% to 83% with velocities between 1490 and 1621 m s(
-1) and broadband ultrasound attenuation (BUA) values in the range 46-
115 dB MHz(-1). The three devices tested were able to discriminate por
osity differences of at least 3%, although the values obtained for the
propagation parameters varied widely. Velocity differences of up to 3
8 m s(-1) and BUA variations of up to 33 dB MHz(-1) were found, althou
gh a relationship was identified between the velocity and BUA measurem
ents. In some cases, the variation can be attributed to differences in
the measurement technique adopted, although there also seem to be det
ailed differences in the definition of the parameters themselves. The
variation between different devices from the same manufacturer (Lunar)
was also studied. Measurements taken from five devices showed variati
on in velocity values of up to 25 m s(-1) (SD 10.8 m s(-1)) and in BUA
values of up to 11 dB MHz(-1) (SD 4.3 dB MHz(-1)). We conclude that t
he variation both between manufacturers and between nominally identica
l machines may be of clinical significance. Both users and manufacture
rs need to consider urgently the introduction of quality standards and
consensus definition of terms and techniques. The fact that all machi
nes studied have been superseded commercially does not invalidate thes
e conclusions, since many of the devices tested remain in clinical use
and there is no evidence of fundamental change in manufacturers' proc
edures.