Engineering analysis of penile hemodynamic and structural-dynamic relationships: Part II—Clinical implications of penile buckling

Abstract

Purpose: Penile buckling force was analytically described in terms of its constituents. In addition, theoretically-derived buckling force data were compared to clinically measured data and the influence of each constituent on penile buckling force data was assessed.Methods: Using engineering buckling theory for a column, a mathematically-derived penile buckling model was developed which incorporated geometric and hemodynamic data obtained by dynamic infusion pharmacocavernosometry studies in 21 impotent patients (age 43, range 24–62 y) as well as penile tissue mechanical characteristics previously developed (Part I).Results: In 17 of 21 patients the mean difference between theoretically derived and clinically measured buckling force data was 0.33±0.25 kg (r=0.96). Factors which increased penile buckling forces were: high intracavernosal pressure values (rigidity was related to pressure in an exponential-like fashion); high penile aspect ratio (D/L) values (relatively large diameter/short length penile geometry) and high flaccid diameter; and high cavernosal expandability values (a measure of the ability of the corpora to approach its erect volume with relatively low intracavernosal pressures).Conclusions: Pressure-volume data (pressure, geometry and tissue characteristics) obtained during erectile function testing have been shown, for the first time, to theoretically predict the magnitude of clinically-measured penile buckling forces.