So a team of biomedical researchers at the University of Helsinki claim to have perfected a system for measuring the efficacy of medications used to treat erectile dysfunction using real-time imaging.
The process, seemingly conceived in a union of the Transportation Safety Authority’s new body-scanning equipment and a time-tested tool for assessing heart function, involves injecting radiocontrast dye into the blood vessels serving the penis and examining what occurs in specific areas of the corpora cavernosum and corpus spongiosum, the mesh-like regions of the organ where blood accumulates and is retained during tumescence. Experiments have involved the IV administration of vasodilators such as sildenafil (known in the U.S. as Viagra) near the base of the penis and assessing what occurs in the “downstream” microcirculation. Since most men with erectile dysfunction have localized rather than generalized circulatory compromise in the small vessels–common culprits are smoking and especially diabetes–this theoretically allows for the placement of small vasodilator patches on the penis in the 30 or so minutes prior to the initiation of sex play. Now that’s romance! And hey, even geometry enters the mix:
Researchers used a portable imaging device or “echophallogram” similar in construction and shape to a small magnetic resonance imaging (MRI) console to assess the progression of tumescence after the intravenous administration of 5 mg sildenafil citrate into the main penile artery 2-3 mm superior to the pubic fat pad. Penile erection fraction (PEF) was computed in real time at 1, 5 and 10 min after drug injection to assess initial efficacy in 19 healthy volunteers aged 25 to 56 yrs (median 37.7 yrs, SD +/- 7.2 yrs). Baseline penile volume (Vb was approximated by treating the detumescent penis as a cylinder apposed to a hemisphere to represent the shaft and the glans respectively, with V = Pi*(D/2)2*L + (2/3)*Pi*(D/2)3; here D = penile diameter and L = shaft length. Vmax was calculated at 30 minutes post-administration of sildenafil. PEF was computed as Vt/Vmax with t = 1, 5, and 10 min after administration respectively. Median Vmax/Vb in these subjects was 2.68 +/- 0.41, similar to values observed in the general Finnish male population previously.[1, 8, 9]
As with oral Cialis and Viagra, this would not have much of an effect in men with psychogenic erectile dysfunction, as vasodilators can only overcome constricted blood vessels, not constricted confidence.
More details on the technology and the results are here.