Application of
Quasistatic Ultrasound Elastography for Examination of Scrotal Lesions
Objectives—The
aims of this study were to investigate the value of applying quasistatic
ultrasound elastography for examination of scrotal lesions, to investigate the
features of normal testes on quasistatic elastography, and to establish whether
testicular and epididymal lesions had specific quasistatic elastographic
features.
Methods—We
screened 1073 patients who underwent color Doppler sonographic examinations of
the testes and epididymides in our hospital and performed quasistatic
elastography to evaluate their sonographic features. Measurement data were
expressed as mean ± SD. For intergroup comparisons, we used paired t tests and independent-samples t tests, withP < .05
considered significant.
Results—Quasistatic
elastography did not reveal any testicular or epididymal abnormalities in 625
cases. Seven cases showed testicular torsion; 3 cases showed testicular
space-occupying lesions (1 case each of a testicular teratoma, testicular
seminoma, and testicular endodermal sinus tumor); 176 cases showed epididymal
lesions (138 cases of caudal epididymal inflammatory masses, 37 cases of caput
epididymal cysts, and 1 case of an epididymal lymphangioma); and 262 cases
showed varicocele. The normal testicular elastographic appearance showed a
3-ring structure: red surrounding bands with a blue edge region and a green
central area. The stiffness in cases of testicular torsion, testicular
space-occupying lesions, and epididymal lesions was increased, whereas caput epididymal
cysts of different diameters appeared either as green, blue-green-red, or
“scooped out.” Elastographic results for patients with varicocele were not
different from those for normal testes.
Conclusions—Quasistatic
elastography can reflect the relative stiffness of the testis and its
surrounding tissues, thus providing a novel, reliable, convenient, and
noninvasive method for clinical detection of testicular stiffness and related
pathologic changes.
o © 2016 by the American Institute of Ultrasound in Medicine
Ex Vivo Assessment of
Sentinel Lymph Nodes in Breast Cancer Using Shear Wave Elastography
Objectives—Axillary
lymph node status is one of the important prognostic factors in early-stage
breast cancer. Despite the combined use of sonography, fine-needle aspiration,
and sentinel lymph node (SLN) dissection, there is a gap between the potential
effectiveness of those techniques and current success to determine the axillary
lymph node status. The main aim of this study was to evaluate the baseline
accuracy of shear wave elastography for differentiation of benign versus
malignant SLNs in an ex vivo artifact-free environment.
Methods—Thirty
patients with breast cancer scheduled for SLN dissection were enrolled
prospectively after informed consent and Institutional Review Board approval
were obtained. After dissection, lymph nodes were embedded in ultrasound gel and
examined with grayscale sonography and shear wave elastography. Findings were
compared to histopathologic results.
Results—A
total of 64 SLNs obtained from the 30 patients were evaluated. Twelve of them
(18.8%) were metastatic, and 52 (81.2%) were benign. The mean cortical
thickness (benign versus metastatic, 1.6 versus 4.4 mm), short-axis length
(4.63 versus 7.50 mm), cortical stiffness (10.7 versus 25.5 kPa), and hilar
stiffness (7.5 versus 11.3 kPa) were statistically higher in metastatic lymph
nodes (P ≤ .02). Area under the receiver operator
characteristic curve values for these variables were 0.814, 0.768, 0.786, and
0.759, respectively. Cortical thickness was found to have the highest
diagnostic performance, followed by cortical stiffness.
Conclusions—Shear
wave elastography can be used with grayscale sonography for evaluation of cases
to decide on needle biopsy sampling. However, it cannot be used as a
replacement for fine-needle aspiration or SLN dissection.
o © 2016 by the American Institute of Ultrasound in Medicine
Renal Cell Carcinomas
Sonographic
Appearance Depending on Size and Histologic Type
Objectives—Prior
studies have demonstrated that approximately 10% of malignant renal cell
carcinomas are as echogenic as angiomyolipomas on sonography. However, a recent
presentation suggested that small (<1-cm also="" always="" angiomyolipomas="" are="" as="" be="" benign="" carcinoma="" carcinomas="" cases="" cell="" confirm="" corresponding="" detected="" echogenic="" entities.="" examined="" hyperechoic="" masses="" may="" o:p="" of="" on="" or="" other="" our="" own="" renal="" some="" sonography.="" sonography="" that="" therefore="" to="" we="" with="">
Methods—Institutional
Review Board approval and Health Insurance Portability and Accountability Act
compliance were maintained for this retrospective review of 91 pathologically
proven cases of renal cell carcinoma, with corresponding sonography. Tumors
were first differentiated by histologic cell type (clear cell, papillary, and
chromophobe). Tumors were then stratified according to 2 size group parameters,
falling into those that were 3 cm or larger and those that were smaller than 3
cm in diameter, with the less than 3-cm group further subdivided into 2 cm or
smaller and greater than 2 cm. Tumor echogenicity was graded on a 5-point scale
with respect to the renal parenchyma.
Results—Forty-six
tumors (51%) were 3 cm in diameter or smaller, and most were found to be either
isoechoic (35%) or mildly hyperechoic (26%) to the surrounding renal
parenchyma. Of tumors smaller than 2 cm, most were either mildly hyperechoic
(29%) or as hyperechoic as renal sinus fat (very hyperechoic; 29%). Tumors
larger than 3 cm were found most often to be either isoechoic (49%) or mildly
hyperechoic (33%), with only 4% found to be very hyperechoic.
Conclusions—The
sonographic appearances of renal cell carcinomas include a small population
that are very hyperechoic on sonography and thus could potentially be
misdiagnosed as angiomyolipomas.
o © 2016 by the American Institute of Ultrasound in Medicine
Diagnostic Accuracy
of SuperSonic Shear Imaging for Staging of Liver Fibrosis
A Meta-analysis
Objectives—The
purpose of this study was to assess the performance of SuperSonic shear imaging
(SuperSonic Imagine SA, Aix-en-Provence, France) for diagnosis of liver
fibrosis.
Methods—Literature
databases were searched to identify relevant studies from inception to February
28, 2015. Sensitivity, specificity, and other information were extracted from
the studies. Pooled data were calculated by a bivariate mixed-effects binary
regression model. Subgroup and sensitivity analyses were performed. Publication
bias was tested by funnel plots.
Results—Twelve
studies were included in this meta-analysis and reported on 1635 patients. The
pooled sensitivity and specificity were 0.78 (95% confidence interval [CI],
0.69–0.85) and 0.95 (95% CI, 0.75–0.99), respectively, for fibrosis stages F≥1,
0.84 (95% CI, 0.81–0.86) and 0.81 (95% CI, 0.74–0.87) for F≥2, 0.89 (95% CI,
0.85–0.93) and 0.84 (95% CI, 0.77–0.89) for F≥3, and 0.88 (95% CI, 0.82–0.91)
and 0.86 (95% CI, 0.81–0.90) for F=4. The areas under the summary receiver
operating characteristic curves were 0.87 (95% CI, 0.84–0.90) for F≥1, 0.85
(95% CI, 0.81–0.88) for F≥2, 0.93 (95% CI, 0.91–0.95) for F≥3, and 0.93 (95%
CI, 0.90–0.95) for F=4. No significant publication bias was found.
Conclusions—SuperSonic
shear imaging could be used for staging of liver fibrosis. Especially, it has
high diagnostic accuracy for severe fibrosis and cirrhosis.
o © 2016 by the American Institute of Ultrasound in Medicine
Performance of
2-Dimensional Ultrasound Shear Wave Elastography in Liver Fibrosis Detection
Using Magnetic Resonance Elastography as the Reference Standard
A Pilot Study
Objectives—To
investigate the correlation between 2-dimensional (2D) ultrasound shear wave
elastography (SWE) and magnetic resonance elastography (MRE) in liver stiffness
measurement and the diagnostic performance of 2D SWE for liver fibrosis when
imaging from different intercostal spaces and using MRE as the reference
standard.
Methods—Two-dimensional
SWE was performed on 47 patients. One patient was excluded from the study. Each
of the remaining 46 patients underwent same-day MRE for clinical purposes. The
study was compliant with the Health Insurance Portability and Accountability
Act and approved by the Institutional Review Board. Informed consent was
obtained from each patient. Two-dimensional SWE measurements were acquired from
the ninth, eighth, and seventh intercostal spaces. The correlation with MRE was
calculated at each intercostal space and multiple intercostal spaces combined.
The performance of 2D SWE in diagnosing liver fibrosis was evaluated by
receiver operating characteristic curve analysis using MRE as the standard.
Results—The
47 patients who initially underwent 2D SWE included 22 female and 25 male
patients (age range, 19–77 years). The highest correlation between 2D SWE and
MRE was from the eighth and seventh intercostal spaces (r = 0.68–0.76). The ranges of the areas under the
receiver operating characteristic curves for separating normal or inflamed
livers from fibrotic livers using MRE as the clinical reference were 0.84 to
0.92 when using the eighth and seventh intercostal spaces individually and 0.89
to 0.90 when combined.
Conclusions—The
results suggest that 2D SWE and MRE are well correlated when SWE is performed
at the eighth and seventh intercostal spaces. The ninth intercostal space is
less reliable for diagnosing fibrosis with 2D SWE. Combining measurements from
multiple intercostal spaces does not significantly improve the performance of
2D SWE for detection of fibrosis.
o \© 2016 by the
American Institute of Ultrasound in Medicine
Integration of
Ultrasound in Medical Education at United States Medical Schools
A National Survey of
Directors’ Experiences
Objectives—Despite
the rise of ultrasound in medical education (USMED), multiple barriers impede
the implementation of such curricula in medical schools. No studies to date
have surveyed individuals who are successfully championing USMED programs. This
study aimed to investigate the experiences with ultrasound integration as
perceived by active USMED directors across the United States.
Methods—In
2014, all allopathic and osteopathic medical schools in the United States were
contacted regarding their status with ultrasound education. For schools with
required point-of-care ultrasound curricula, we identified the USMED directors
in charge of the ultrasound programs and sent them a 27-question survey. The
survey included background information about the directors, ultrasound program
details, the barriers directors faced toward implementation, and the directors’
attitudes toward ultrasound education.
Results—One-hundred
seventy-three medical schools were contacted, and 48 (27.7%) reported having a
formal USMED curriculum. Thirty-six USMED directors responded to the survey.
The average number of years of USMED curriculum integration was 2.8 years (SD,
2.9). Mandatory ultrasound curricula had most commonly been implemented into
years 1 and 2 of medical school (71.4% and 62.9%, respectively). The most
common barriers faced by these directors when implementing their ultrasound
programs were the lack of funding for faculty/ equipment (52.9%) and lack of
time in current medical curricula (50.0%).
Conclusions—Financial
commitments and the full schedules of medical schools are the current
prevailing roadblocks to implementation of ultrasound education. Experiences
drawn from current USMED directors in this study may be used to help programs
starting their own curricula.
o © 2016 by the American Institute of Ultrasound in Medicine
Medical Student Core
Clinical Ultrasound Milestones
A Consensus Among
Directors in the United States
Objectives—Many
medical schools are implementing point-of-care ultrasound in their curricula to
help augment teaching of the physical examination, anatomy, and ultimately
clinical management. However, point-of-care ultrasound milestones for medical
students remain unknown. The purpose of this study was to formulate a consensus
on core medical student clinical point-of-care ultrasound milestones across
allopathic and osteopathic medical schools in the United States. Directors who
are leading the integration of ultrasound in medical education (USMED) at their
respective institutions were surveyed.
Methods—An
initial list of 205 potential clinical ultrasound milestones was developed
through a literature review. An expert panel consisting of 34 USMED directors
across the United States was used to produce consensus on clinical ultrasound
milestones through 2 rounds of a modified Delphi technique, an established
anonymous process to obtain consensus through multiple rounds of quantitative
questionnaires.
Results—There
was a 100% response rate from the 34 USMED directors in both rounds 1 and 2 of
the modified Delphi protocol. After the first round, 2 milestones were revised
to improve clarity, and 9 were added on the basis of comments from the USMED
directors, resulting in 214 milestones forwarded to round 2. After the second
round, only 90 milestones were found to have a high level of agreement and were
included in the final medical student core clinical ultrasound milestones.
Conclusions—This
study established 90 core clinical milestones that all graduating medical
students should obtain before graduation, based on consensus from 34 USMED
directors. These core milestones can serve as a guide for curriculum deans who
are initiating ultrasound curricula at their institutions. The exact method of
implementation and competency assessment needs further investigation.
o © 2016 by the American Institute of Ultrasound in Medicine
