Table 1:

Subharmonic response (and correlation) of commercial UCAs to a pressure increase of approximately 185 mmHg.

UCA	Manufacturer	Subharmonic signal reduction (dB)	Linear regression (r2)
Definity	Lantheus Medical Imaging, N Billerica, MA, USA	11.0 ± 0.3	0.98
Levovist	Schering AG, Berlin, Germany	9.6 ± 0.2	0.98
Lumason aka SonoVue	Bracco, Milan, Italy	1.0 ± 1.3	0.20
Optison	GE Healthcare, Princeton, NJ, USA	10.1 ± 0.2	0.97
Sonazoid	GE Healthcare, Oslo, Norway	13.3 ± 0.2	0.99