A dilating device for the prostatic urethra comprising: at least three, laterally connected ridges, wherein each ridge is configured to longitudinally engage with a different substantially longitudinal groove of the prostatic urethra of a patient, and wherein the at least three laterally connected ridges are configured to laterally compress to enable insertion into the prostatic urethra in a compressed configuration, and wherein the at least three laterally connected ridges are configured to laterally expand to a normally-open configuration upon deployment within the prostatic urethra, to exert a radially outwards force that dilates the prostatic urethra.
