Hamdan Extrainguinal Sub-Oblique (HESO) reservoir placement technique for inflatable penile prosthesis

Inflatable penile prosthesis (IPP) implantation remains the most effective solution for refractory erectile dysfunction.1 For decades, the standard has been retropubic reservoir placement in the space of Retzius. Still, this approach carries rare yet potential risks of visceral and vascular injury, especially in patients with hostile pelvic anatomy resulting from prior surgery or radiation.2 This has led to the development of alternative ectopic placement techniques; however, these methods have their distinct trade-offs. Approaches that utilize the inguinal canal, such as high submuscular or sub-external oblique placements, risk interaction with inguinal structures, potentially causing nerve injury or spermatic cord compression. These techniques are often unsuitable for patients with a history of previous hernia repairs, and concerns about reservoir palpability are particularly common in thinner individuals. Additionally, the reliability of the inguinal canal techniques has been questioned by cadaveric studies showing misplacement rates as high as 35%.3 Conversely, other techniques achieve a deep, submuscular placement to avoid the inguinal canal. The single-incision medial sub-rectus (Kava) approach, while performed under direct vision, has demonstrated a potential for unintended posterior extension of the reservoir tip through the transversalis fascia, resulting in intraperitoneal contact with bowel loops.4 Some other deep placements require a second abdominal incision, which increases surgical complexity and postoperative discomfort. Overall, these limitations suggest an opportunity for an alternative approach that allows reliable ectopic reservoir placement without entering the Space of Retzius or the inguinal canal (Supplementary Table S1).