The feasibility study of shear wave elastography in the diagnosis of erectile dysfunction

Abstract

The aim of this study was to explore the value of Shear wave elastography (SWE) in evaluating vascular and nonvascular erectile dysfunction. In this study, erectile dysfunction (ED) patients enrolled (n = 114) received SWE and Doppler ultrasonography (PCDU) exams. The peak systolic velocity (PSV) and end-diastolic velocity (EDV) were used as the classification standard. The performance of the SWE was assessed with the receiver operating characteristic curve, sensitivity and specificity. The rigidity alterations of corpus cavernosum penis with age was also investigated. SWE values of corpus cavernosum penis (CCP) before intracavernosal injection (ICI) negatively correlated with age of patients in vascular ED group (r = -0.288, P < 0.05). In erectile or flaccid state, the SWE value of vascular ED was significantly larger than non-vascular ED. When the cut-off value for SWE values of CCP 0.88 m/s in erectile state and 2.32 m/s in flaccid state, the areas under the receiver operating characteristic (ROC) curve were 0.700 (sensitivity: 77.78%, specificity: 60.00%) and 0.612(sensitivity: 68.52%, specificity: 51.67%) in erectile or flaccid state, respectively. This study provides preliminary evidence that SWE in flaccid state could be non-invasive methods used to moderate predict vascular ED.

Fig. 1

Distribution and correlation of Shear wave elastography (SWE) value of corpus cavernosum penis (CCP) with age in patients with erectile dysfunction (ED) before intracavernous injection of alprostadil (ICI). (a) Scatter plot showed that there was significant correlation between SWE value of CCP and age of patients in vascular ED (r = -0.288, P = 0.035). (b) Scatter plot showed that there was no significant correlation between SWE value of CCP and age of patients in non-vascular ED (r = 0.045, P = 0.732).

Fig. 2

Distribution and correlation of Shear wave elastography (SWE) value of corpus cavernosum penis (CCP) with age in patients with erectile dysfunction (ED) after intracavernous injection of alprostadil (ICI). (a) Scatter plot showed that there was no significant correlation between SWE value of CCP and age of patients in vascular ED (r=−0.052, P = 0.708). (b) Scatter plot showed that there was no significant correlation between SWE value of CCP and age of patients in non-vascular ED (r = 0.007, P = 0.960).

Fig. 3

Doppler images and Shear wave elastography (SWE) images of corpus cavernosum penis (CCP). Doppler images show peak systolic velocity (PSV) 73.1 cm/s at 5–10 min after ICI form a patient with non-vascular ED (A; 29 years old), PSV 14.7 cm/s at 5–10 min after ICI form a patient with arterial ED (D; 46years old) and PSV 31.9 cm/s and end-diastolic velocity (EDV) 8.3 cm/s at 5–10 min after ICI form a patient with venogenic ED (G; 32 years old). SWE images of the transverse plane of CCP from a patient with non-vascular ED (B,C), a patient with arterial ED (E,F) and a patient with venogenic ED (H,I). Mean SWE values of CCP before (B) and 5–10 min after ICI (C) were 2.26 m/s and 0.72 m/s in non-vascular ED, respectively. Mean SWE values of CCP before (E) and 5–10 min after ICI (F) were 2.76 m/s and 1.60 m/s in arterial ED, respectively. Mean SWE values of CCP before (H) and 5–10 min after ICI (I) were 2.45 m/s and 1.82 m/s in venogenic ED, respectively.

Fig. 4

(a) Receiver operator characteristic (ROC) curve of Shear wave elastography (SWE) values of corpus cavernosum penis (CCP) before intracavernous injection (ICI) of alprostadil in distinguishing vascular erectile dysfunction (ED) from non-vascular ED. The cut-off value is 2.32 m/s. And the Area Under Curve AUC was 0.612. (b) ROC curve of SWE values of CCP after intracavernous injection (ICI) of alprostadil in distinguishing vascular erectile dysfunction (ED) from non-vascular ED. The cut-off value is 0.88 m/s. And the AUC was 0.700.