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814.6 3D Imaging
0.06 ± 0.02 m/s, while the average PSV within
cancer is 0.3 m/s. Pulsed Doppler in breast carcinoma is thought to exhibit the following fi gures:
PSV, 0.05–0.47 m/s; EDV, 0.07–0.09 m/s;
RI, 0.67–0.81; and PI, 1.47-1.76 (Tro fi mova
2000a, b ; Fisenko and Sandrikov 1998 ; Madjar
et al. 1995 ; Youssefzadeh et al. 1996 ) . According
to Lee et al. ( 1995 ) , PSV in 67 % of breast carcinomas exceeds 0.15 m/s.
According to Shevchenko ( 1999 ) , the velocities of arterial blood fl ow in malignant tumors are
as follows: PSV, 4.6–56.6 cm/s (average value,
18.98 cm/s); EDV, 0.3–9.8 cm/s (average
value, 2.99 cm/s); and RI, 0.56–1.34 (average
value, 0.82). The larger the number of vessels in
a tumor, the higher blood velocities and RI are
registered.
Tro fi mova ( 2000 b ) reported the following
blood fl ow parameters within breast carcinoma:
PSV, 0.27 (0.06–0.91) m/s; EDV, 0.07 (0.01–
0.33) m/s; RI, 0.76 (0.31–1.42); and PI, 1.71
(0.46–8.09). She noticed that blood fl ow parameters in the vessels around the tumor are close to
the data obtained in the areas of mastopathy. Lee
et al. ( 1995 ) did not reveal any difference between
the vascular pattern around benign breast tumor
and healthy tissue of contralateral breast.
According to Trufanov et al. ( 2009 ) , the
increase in RI, PSV, and EDV is characteristic for
malignant breast lesions. The authors also noticed
that the same parameters are often observed in
women with only diffuse breast changes.
Spectral characteristics of blood fl ow in the
vessels of in fi ltrative breast carcinoma are very
variable, starting from almost normal curve with
pulsed Doppler ending with shunts and low-resistive pathological vessels, irregular dilatations,
disorganization of vascular pattern, and different
caliber of detected vessels ( Zabolotskaya and
Zabolotsky 2000 ) .
Sinyukova et al. ( 2007 ) noticed that pulsedwave Doppler for breast carcinoma is the most
subjective US modality among all diagnostic
techniques.
According to Sohn et al. ( 1997 ) , the methods
of quantitative assessment of imaged vessels are
labor-consuming and unreliable. Most often no
regularity in the change of velocities and indexes
is detected. Wide distribution of indicators of
pulsed Doppler does not supply any signi fi cant
diagnostic information, often fails to serve a criterion for differential diagnosis of breast lesions,
and can be only considered an accessory sign.
The combination of grayscale US with spectral and color Doppler permits to obtain additional information and increase the sensitivity of
US in diagnosis of cancer from 82–97 to 93–99 %
and speci fi city from 59 to 83–97 % (Possover
et al. 1994 ; Sohn et al. 1997 ) . The majority of
authors note the following criteria for differential
diagnosis of breast carcinoma: arteriovenous
shunts, change in PSV and EDV, absence of enddiastolic component, increased RI, detection of
more than three vessels, and irregular course and
calibers of vessels within the lesion (Yang et al.
1996 ; Tro fi mova 2000a, b ) .
The sensitivity Doppler imaging in diagnosis of
breast carcinoma is 81–99 %, speci fi city is 71–98 %,
and diagnostic accuracy is 82–93 % ( Fisenko and
Sandrikov 1998 ; Tro fi mova 2000 b ) .
4.6 3D Imaging
Computer processing of US image permits threedimensional (3D) reconstruction of breast struc-
ture and its lesions to facilitate assessment of
borders and topographic interrelation with surrounding tissues (Figs. 4.8 and 4.9 ).
The technology can be carried out with special
volume (3D) probes or by means of application
of conventional linear US probes with subsequent
computer processing of the obtained data. In the
latter case, the probe is positioned perpendicularly to investigated object (region of interest).
The scanning starts from the area, where the
object is out of view, follows slowly down over
the object, and ends after its disappearance.
3D image allows getting sections of the lesion
in any plain (frontal, axial, and sagittal) at all
depths. It opens certain prospects in respect of
postprocessing of the obtained US volume and its
archiving for delayed analysis.
3D image reconstruction of US breast structure is advantageous over other imaging methods,
which supply only plane images. 3D US of breast
82
4 Ultrasound Diagnosis of Breast Cancer
Fig. 4.8 Breast carcinoma. 3D US
834.6 3D Imaging
Fig. 4.8 (continued)
84
4 Ultrasound Diagnosis of Breast Cancer
Fig. 4.8 (continued)
854.6 3D Imaging
Fig. 4.8 (continued)
86
4 Ultrasound Diagnosis of Breast Cancer
Fig. 4.9 Breast carcinoma. 3DPD
874.6 3D Imaging
Fig. 4.9 (continued)
88
4 Ultrasound Diagnosis of Breast Cancer
Fig. 4.9 (continued)
894.6 3D Imaging
Fig. 4.9 (continued)
90
4 Ultrasound Diagnosis of Breast Cancer
carcinoma permits not only to assess the number
and structure of lesions within breast structure
but also to specify their location in relation to the
capsule, the signs of invasion (such as indistinct
tuberous margins, discontinuous capsule, and
spreading of the tumor out of the breast to adjacent organs) in detail, presence of calci fi cations,
and multinodosity and to assume the volume of
affected and intact breast tissue. 3D often allows
objective analysis of the lesion in dynamics, such
as the change in shape and inner structure, especially against fi brous changes in recurrent tumors.
The possibility of rotation and obtaining multislice images facilitates subjective perception of
abnormalities. Sometimes it enables to reduce
diagnostic terms and to improve early diagnosis
of breast malignancies.
3D reconstruction of US image in vascular
regimen (3D Power Doppler imaging, 3DPD)
permits more precise assessment of pathological
transformation of vessels within a malignant
lesion, their density, and disorganized course.
The symmetry and regularity of vascular pattern
and presence of dilated and narrowed segments
are assessed more often. The character of perinodular and intranodular vascularization and the disorganized vascular pattern (Fig.
4.9 ) are accurately
de fi ned.
4D mode (real-time 3D) utilizes special US
probes and high-quality scanners. Constantly
repeating 3D scanning and display of an object is
performed in real time. It signi fi cantly reduces
examination time. Fast acquisition of volume
data allows precise de fi nition of breast structure
and spatial features of its vascularity with smaller
noise and artifacts, especially in cases of breast
lesions. That enables to carry out detailed and
more con fi dent differential diagnosis of mixed or
incomplete types of vascular patterns within
breast lesions.
Numerous methods of optimization of US
image in gray scale, Doppler mapping, 3D reconstruction, and the technology of enhanced fi ltration
depending on regions of interest signi fi cantly
improve contrast of US image and reduce the
number of artifacts and noises. Wide choice of
postprocessing options signi fi cantly reduces the
time of the examination and improves its quality.
4.7 Ultrasound Elastography
Ultrasound elastography (sonoelastography,
RTE, EUS) is the US technology, which is based
on the assessment of tissue stiffness and elasticity. Variations in elasticity of different tissues
under external compression enable imaging of
hard and soft structures. It permits to detect cancer at early stages and to diagnose the size, shape,
and structure of malignant tumors more precisely
( Sencha et al. 2010a, b ) .
Mechanical properties of biological tissues
depend on macromolecular components (parenchyma, fat, collagen, etc.). Tissue elasticity is characterized by tissue shift or distortion in response to
external compression. Differences in elasticity of
different tissues with compression result in changes
of re fl ection of ultrasound. Elastography is based
on expanded combined autocorrelative method
that processes traditional echographic images of
distortable tissues. Special mathematically based
algorithms are used to correct possible lateral shifts
of a lesion out of two-dimensional scanning range.
Some scanners incorporate a feature of obtaining
data about tissue elasticity basing on mechanical
wave distribution from puling large vessels, heart,
or chest. No additional external compression with
an US probe or very limited compression is
required in such cases.
J. Ophir et al. were the fi rst to introduce elastography for diagnostics in early 1990s of the
twentieth century. The technology was constantly
improving. Attempts have been taken to use elastography in the early diagnosis of mammary cancer (Garra et al. 1997 ; Zubarev 2009 ) , prostate
cancer, ovarian carcinoma, uterine cancer (Mitkov
et al. 2011 ) , in fl ammatory changes, liver metastases, thyroid gland (Sencha et al. 2009 ) , metastatic
neck lymph nodes, parathyroid cancer, tumors of
the salivary glands, etc.
Depending on the technique of elastography,
the following varieties are speci fi ed ( Zubarev
2009 ) :
1. Elastography with manual compression of tis-
sues. The sonographer pushes the US probe to
achieve tissue shift or deformation.
2. Elastography based on pulsation of large
vessels.