Strain elastography proven superior to shear wave for assessing breast mass stiffness
Researchers found that strain elastography is superior to shear wave elastography for the assessment of breast lesion stiffness. The group published their findings this week in Clinical Imaging.
Ultrasound elastography is a technology that analyzes tissue stiffness by applying pressure to lesions during imaging. Malignant tumors are typically less malleable than benign tumors, and elastography is a great method for differentiating between the two.
There are two types of elastography: strain (SE) and shear wave (SWE). SE works by applying manual pressure to the tumor and surrounding tissue, while SWE uses acoustic radiation force impulses that produce shear waves to the area.
While both have been historically advantageous for evaluating tumors, some malignancies defy standard characteristics and therefore may benefit from one method over another.
“While there is much published data on the accuracy of the different elastography techniques, there exists relatively little research directly comparing SE and SWE techniques, and whether the technical advantages of SWE necessarily translate to better performance over SE,” Ian Wei Ming Tay, with the Department of Diagnostic Radiology at Singapore General Hospital, and co-authors explained.
In order to compare the two elastography methods, experts gathered 81 women who agreed to have an elastographic assessment before undergoing biopsy. SE and SWE evaluated a combined total of 101 masses for sensitivity and specificity.
The sensitivity and specificity of SE was 94.7% and 81.0%, compared to 73.7% and 82.5% for SWE, respectively.
The researchers noted that soft cancers are often more difficult to detect and may still elude elastography technology. In their study, two invasive mucinous carcinomas were present. One of these tumors was detected by SE, the other by histological evaluation. SWE did not detect either of the two.
“We postulate that SE can accurately diagnose necrotic tumors because it measures the combined stiffness of the lesion's core and boundary,” the experts wrote.
The authors conceded that more research comparing SE and SWE on a bigger scale is necessary to definitively determine the best practices that would guide radiologists’ grading of breast masses. However, in their research, SE was found to be superior over SWE for the assessment of tissue stiffness.
You can view the detailed research in Clinical Imaging.