1/
Fetal Sex and Intrauterine Growth Patterns
Objectives—To
analyze the effect of fetal sex on intrauterine growth patterns during the
second and third trimesters.
Methods—We
conducted a cross-sectional study of women with uncomplicated singleton
pregnancies who underwent sonographic fetal weight estimation during the second
and third trimesters in a single tertiary center. The effect of fetal sex on
intrauterine growth patterns was analyzed for each of the routine fetal
biometric indices (biparietal diameter, head circumference, occipitofrontal
diameter, abdominal circumference, and femur length) and their ratios.
Sex-specific regression models were generated for these indices and their
ratios as a function of gestational age. Sex-specific growth curves were
generated from these models for each of the biometric indices and their ratios
for gestational weeks 15 to 42.
Results—Overall,
12,132 sonographic fetal weight estimations were included in the study. Fetal
sex had an independent effect on the relationship between each of the biometric
indices and their ratios and gestational age. These effects were most
pronounced for biparietal diameter (male/female ratio, 1.021) and the head
circumference/femur length and biparietal diameter/femur length ratios
(male/female ratios, 1.014 and 1.016, respectively). For the head measurements,
these sex-related differences were observed as soon as the early second
trimester, whereas for abdominal circumference, the differences were most
notable during the late second and late third trimesters.
Conclusions—Female
fetuses grow considerably slower than male fetuses, and these differences are
observed from early gestation. However, the female fetus is not merely a
smaller version of the male fetus, but, rather, there is a sex-specific growth
pattern for each of the individual fetal biometric indices. These findings
provide support for the use of sex-specific sonographic models for fetal weight
estimation as well as the use of sex-specific reference growth charts.
o
© 2013 by the American Institute of
Ultrasound in Medicine
2/
Clinical Value of Radiofrequency Ultrasonic
Local Estimators in Classifying Breast Lesions
Objectives—We
sought to summarize the features of radiofrequency ultrasonic local estimator
(RULES) images of benign and malignant masses and to explore the diagnostic
value of RULES scores to identify breast lumps.
Methods—A
total of 81 women with a mean age ± SD of 41.33 ± 12.03 years (range, 19–68
years) with 82 lesions seen at our hospital were included in this study.
Inclusion criteria were Breast Imaging Reporting and Data System grade 2 to 5
breast lesions, preoperative 2-dimensional (2D) ultrasound (US) examinations
and RULES image acquisition, no treatment before the US examinations, surgical
resection in our hospital, and histopathologic results. Each RULES
characteristic was scored on the basis of expected values for malignant
characteristics, and this RULES scoring system was assessed by a receiver
operating characteristic curve.
Results—Of
the 82 lesions, 45 were benign, and 37 were malignant. Malignancy was
associated with multiple colors, red as the main color, colors distributed in 3
or more locations, aggregated colors, and more than half of the area filled
with colors. A RULES score of 7 had the highest sum of sensitivity (67.6%) and
specificity (95.6%) and the highest accuracy (82.9%) for diagnosis of
malignancy. When 2D US imaging a Breast Imaging Reporting and Data System
category of 4 was combined with a RULES score of 4 to detect breast cancer, the
sensitivity was 83.8%; the specificity was 93.3%; and the accuracy increased to
89.0%.
Conclusions—The
use of RULES images and characteristics is helpful in differentiating benign
and malignant breast lesions. Diagnostic accuracy can be improved by combining
2D US imaging and RULES.
o
© 2013 by the American Institute of
Ultrasound in Medicine
3/
Breast Mass Characterization Using
3-Dimensional Automated Ultrasound as an Adjunct to Digital Breast
Tomosynthesis
A Pilot Study
Objectives—The
purpose of this study was to retrospectively evaluate the effect of
3-dimensional automated ultrasound (3D-AUS) as an adjunct to digital breast
tomosynthesis (DBT) on radiologists’ performance and confidence in
discriminating malignant and benign breast masses.
Methods—Two-view
DBT (craniocaudal and mediolateral oblique or lateral) and single-view 3D-AUS
images were acquired from 51 patients with subsequently biopsy-proven masses
(13 malignant and 38 benign). Six experienced radiologists rated, on a 13-point
scale, the likelihood of malignancy of an identified mass, first by reading the
DBT images alone, followed immediately by reading the DBT images with
automatically coregistered 3D-AUS images. The diagnostic performance of each
method was measured using receiver operating characteristic (ROC) curve
analysis and changes in sensitivity and specificity with the McNemar test.
After each reading, radiologists took a survey to rate their confidence level
in using DBT alone versus combined DBT/3D-AUS as potential screening
modalities.
Results—The
6 radiologists had an average area under the ROC curve of 0.92 for both
modalities (range, 0.89–0.97 for DBT and 0.90–0.94 for DBT/3D-AUS). With a
Breast Imaging Reporting and Data System rating of 4 as the threshold for
biopsy recommendation, the average sensitivity of the radiologists increased
from 96% to 100% (P
> .08) with 3D-AUS, whereas the specificity decreased from 33% to 25% (P
> .28). Survey responses indicated increased confidence in potentially using
DBT for screening when 3D-AUS was added (P
< .05 for each reader).
Conclusions—In
this initial reader study, no significant difference in ROC performance was
found with the addition of 3D-AUS to DBT. However, a trend to improved
discrimination of malignancy was observed when adding 3D-AUS. Radiologists’
confidence also improved with DBT/3DAUS compared to DBT alone.
o
© 2013 by the American Institute of
Ultrasound in Medicine
4/
Evaluation of Carotid Artery Stiffness in
Obese Children Using Ultrasound Radiofrequency Data Technology
Objectives—The
goals of this study were to investigate the difference in carotid arterial
stiffness in obese children compared to healthy children and to study the
correlation between carotid arterial stiffness parameters and obesity using
ultrasound (US) radiofrequency (RF) data technology.
Methods—Carotid
artery stiffness parameters, including the compliance coefficient, stiffness
index, and pulse wave velocity, were evaluated in 71 obese patients and 47
healthy controls with US RF data technology. In addition, all participants were
evaluated for fat thickness in the paraumbilical abdominal wall and fatty liver
using abdominal US.
Results—Compared
to the control group, the blood pressure (BP), body mass index (BMI), fat
thickness in the paraumbilical abdominal wall, presence of fatty liver, and
carotid stiffness parameters (stiffness index and pulse wave velocity) were
significantly higher in the obese group, whereas the compliance coefficient was
significantly lower in the obese group. Furthermore, the pulse wave velocity
was weakly positively correlated with the BMI, systolic BP, diastolic BP, and
paraumbilical abdominal wall fat thickness, whereas the compliance coefficient
was weakly negatively correlated with the systolic BP, BMI, and paraumbilical
abdominal wall fat thickness. The presence of a fatty liver was moderately
positively correlated with the BMI and weakly positively correlated with the
pulse wave velocity.
Conclusions—Ultrasound
RF data technology may be a sensitive noninvasive method that can be used to
accurately and quantitatively detect the difference in carotid artery stiffness
in obese children compared to healthy children. The detection of carotid
functional abnormalities and nonalcoholic fatty liver disease in obese children
should allow early therapeutic intervention, which may prevent or delay the
development of atherosclerosis in adulthood.
o
© 2013 by the American Institute of Ultrasound
in Medicine
5/
Evaluation of Liver Tumors Using Acoustic
Radiation Force Impulse Elastography and Correlation With Histologic Data
Objectives—Acoustic
radiation force impulse (ARFI) technology represents an innovative method for
the quantification of tissue elasticity. The aims of this study were to
evaluate elasticity by ARFI in both liver tumors and background liver tissue
and to compare ARFI measurements with histologic data in liver tumors and
background liver.
Methods—Seventy-nine
tumors were prospectively studied: 43 benign and 36 malignant. Acoustic
radiation force impulse measurements for each tumor type were expressed as mean
± standard deviation for both liver tumors and background liver; ARFI data were
also correlated with histologic data.
Results—For
liver tumors, the mean stiffness values were 1.90 ± 0.86 m/s for hepatocellular
adenoma (n = 9), 2.14 ± 0.49 m/s for hemangioma (n = 15), 3.14 ± 0.63 m/s for
focal nodular hyperplasia (n = 19), 2.4 ± 1.01 m/s for hepatocellular carcinoma
(n = 24), and 3.0 ± 1.36 m/s for metastasis (n = 12). Important variations were
observed within each tumor type or within a single tumor. These variations
could have been due to necrosis, hemorrhage, or colloid. There was no
statistically significant difference between the benign and malignant groups.
Regarding background liver, it was possible to observe pathologic abnormalities
in histologic analyses or liver function tests to explain the ARFI data. The
degree of fibrosis was not the only determinant of liver stiffness in
background liver; other factors such as portal embolization, sinusoidal
obstruction syndrome caused by chemotherapy, and cholestasis, also could have
interfered.
Conclusions—Acoustic
radiation force impulse elastography could not allow differentiation between
benign and malignant tumors. This study provides a better understanding of the
correlation between ARFI and histologic data for both tumors and background
liver.
o
© 2013 by the American Institute of
Ultrasound in Medicine
6/
Ultra–Minimally Invasive Sonographically
Guided Carpal Tunnel Release
Anatomic Study of a New Technique
Objectives—The
purposes of this study were to measure a safe zone and a path for ultra–minimally
invasive sonographically guided carpal tunnel release with a 1-mm incision in
healthy volunteers and then test the procedure in cadavers.
Methods—First,
a previously reported sonographic zone was defined as the space between the
median nerve and the closest ulnar vascular structure. Axially, the safest
theoretical cutting point for carpal tunnel release was set by bisecting this
zone. Magnetic resonance imaging was used for axially determining the limits of
the sectors (origin at the cutting point) that did not enclose structures at
risk (arteries and nerves) and coronally for determining whether our release
path could require directions that could potentially compromise safety (origin
at the pisiform’s proximal pole). Second, in cadavers, we performed
ultra–minimally invasive sonographically guided carpal tunnel release from an
intracarpal position through a 1-mm antebrachial approach. Efficacy (deepest
fibrous layer release rate), safety (absence of neurovascular or tendon
injury), and damage to any anatomy superficial to transverse carpal ligament
were assessed by dissection.
Results—All
11 of our volunteers (22 wrists) had safe axial sectors located volar and
radially of at least 80.4º (considered safe). Release path directions were
theoretically safe (almost parallel to the longitudinal axis of the forearm).
In 10 cadaver wrists, ultra–minimally invasive sonographically guided carpal
tunnel release was effective (100% release rate) and safe without signs of
intrusion into the superficial anatomy.
Conclusions—Ultra–minimally
invasive sonographically guided carpal tunnel release in a safe sonographic
zone may be feasible The technique preserves the superficial anatomy and
diminishes the damage of a surgical approach.
o
© 2013 by the American Institute of
Ultrasound in Medicine
