ENGINEERING ANALYSIS OF PENILE HEMODYNAMIC AND STRUCTURAL-DYNAMIC RELATIONSHIPS - PART II - CLINICAL IMPLICATIONS OF PENILE BUCKLING

Purpose: Penile buckling force was analytically described in terms of its constituents. In addition, theoretically-derived buckling force da ta were compared to clinically measured data and the influence of each constituent on penile buckling force data was assessed. Methods: Usin g engineering buckling theory for a column, a mathematically-derived p enile buckling model was developed which incorporated geometric and he modynamic data obtained by dynamic infusion pharmacocavernosometry stu dies in 21 impotent patients (age 43, range 24-62 y) as well as penile tissue mechanical characteristics previously developed (Part I). Resu lts: In 17 of 21 patients the mean difference between theoretically de rived and clinically measured buckling force data was 0.33+/-0.25 kg ( r=0.96). Factors which increased penile buckling forces were: (1) high intracavernosal pressure values (rigidity was related to pressure in an exponential-like fashion); (2) high penile aspect ratio (D/L) value s (relatively large diameter/short length penile geometry) and high fl accid diameter; and (3) high cavernosal expandability values (a measur e of the ability of the corpora to approach its erect volume with rela tively low intracavernosal pressures). Conclusions: Pressure-volume da ta (pressure, geometry and tissue characteristics) obtained during ere ctile function testing have been shown, for the first time, to theoret ically predict the magnitude of clinically-measured penile buckling fo rces.