Objective To obtain a cut off value strain ratio using strain elastography (SE) to distinguish between benign and malignant peripheral lung lesions.
Methods We recruited 101 patients with peripheral lung lesions in cross-sectional study. Sensitivity, specificity, accuracy of a cut-off value, positive predicted value (PPV), and negative predicted value (NPV) are acquired at the end of the study.
Results We evaluated strain ratios done using strain elastography targeting reference region (Ref) vs region of interest (ROI) in patients who had already been diagnosed by biopsy, histological investigation, microbiological testing, or radiological imaging. In our study, a cut off value regarding strain ratio ? 1.75 is considered statistically significant as malignant lesion (p < 0.001).
Conclusion Using strain elastography, a peripheral parenchymal lung lesion can be classified as malignant based on the strain ratio.
Table (1):Strain ratios in patients with benign and malignant lesions
| Average component | Benign (n=42) | Malignant (n= 59) | P value |
| Min. - Max. | 0.06 - 2.33 | 1.75 - 5 | <0.001 |
| Median (IQR) | 0.13 ( 0.09 - 0.18 ) | 2.57 (2.30 ? 2.78) | <0.001 |
Table (2):Diagnostic performance for strain ratio to discriminate Malignant (n=59) from Benign (n =42)
| AUC | p | 95% C.I | cut-off | sensitivity | specificity | ppv | npn | |
| Average component | 0.993 | <0.001 | 0.979 ? 1.000 | >1.75 | 98.31 | 97.62 | 98.3 | 97.6 |