It is a failure to retain the blood within the cavernous bodies. When the penis fills, the pressure inside increases, and “venules” are opened, allowing blood to escape. This is called “veno-occlusive” incompetence in medicine of the corpora cavernosa, or venous leak, leading to a loss of tone and the impossibility of the sexual act.
Surgery for venous leak correction was very adopted until some time ago. Today it is known that the leak-venous surgery may have relapsed, so with the modern existing drugs, the indication and surgical treatment for escape venous dropped sharply and only in some specific cases should be adopted at the level investigational as I Brazilian Consensus on Sexual Dysfunction - SBU in 1998.
It is advisable in such cases to a specialist (Andrologist) to guide you to them.