Tissue Characterization Consulting

A - 4850 TIMELKAM, Lenaustr.10 - AUSTRIA

Tel/Fax +43-7672-94646

Ultrasound tissue-mimicking reference object (R-Phantom)

The reference object or R-Phantom follow the Rayleigh distribution of gray levels. The histogram (Fig.1) calculated from RF signal shows this distribution.

The gray level transfer function of ultrasound B-image instruments may be calculated from available digitized B-images data. The gray level image analysis shows the typical histogram of logarithmic compression and is similar to Rayleigh distribution in logarithmic scale.

The digitized images of the reference object images are the basis for image normalization, gray scale calibration and time gain correction (TGC). The special software for image normalization and TGC correction is available.

The normalization and gray scale calibration recover the statistical parameter of first order as gray levels mean and standard deviation. Both parameters correlate well with pathology of liver. The software for estimation of parameters of diffused liver diseases is an extension of software for image normalization and TGC correction.

Fig 1. R-phantom Rayleigh distribution of B-image gray levels with ideal linear transfer function.

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Subject to change without notice

⁺ Patent pending

Model PH160-x.x ref⁺

SPECIFICATIONS

Material: Artificial foam

Type 1, 2 and 3

Speed of sound:

c_ph=c_w + 30 m/s (1540 m/s at 20°C)

c_ph= speed of sound in phantom

c_w= speed of sound in water *

Attenuation: x.x nominal

Type 1: ~ 0.7 dB/cm/MHz**

Type 2: ~ 0.45 dB/cm/MHz**

Type 3: ~ 0.3 dB/cm/MHz**

Targets: No discrete targets

Scan window: Polyurethane

11cm x 5.5cm (0.25 mm)

Description: 16cm x 12cm x 6.5cm

Warranty:

Foam : 10 Years

Scan window: 2 Years

(under the condition of proper use)

*c_w - diagram

**Temperature dependence of Attenuation

_{a(f) = ao[1-t(T-To)}^e_]f ^g[1+k(T-To)]

a in dB/cm To=20^oC

T in degrees Celsius ( T>20^oC), f in MHz

type 1 type2 type3

_{ao 0.6663 0.4371 0.3285}

t 0.1804 0.1729 0.1276

e 0.4423 0.4948 0.5631

g 1.3063 1.4147 1.3931

^{k 0.0042 0.0085 0.0047}