Complications of the Penuma penile implant for genital enhancement

cosmetic surgery, penile enlargement, subcutaneous penile implant

The Penuma penile implant (PPI) is a subcutaneous silicone implant used to enhance the flaccid penile length and girth. There are limited data regarding the complications associated with the implant. Current literature is limited by single surgeon experiences and studies with poor follow-up.^1,2 The true incidence of explant, especially due to sexual dysfunction or poor cosmesis is unknown. Given the concerns of severe complications to young patients with no underlying sexual dysfunction, the Sexual Medicine Society of North America recommended PPIs only be performed on IRB approved research protocols.³ Over the last decade, we have seen an increasing number of patients present to our Center with complications of PPIs. These include severe complications that are not discussed in contemporary literature describing the procedure. We present our single center experience managing PPI patients who presented desiring removal or with complications following explant.

Following IRB approval (#349), we retrospectively identified patients who underwent PPI removal at our institution or presented with complications following explant. We collected demographic, clinical, and functional outcome data. Early in our experience, we noticed patients could develop significant dorsal curvature following explant. Thus, we developed a protocol to wait 6 months for capsular contraction vs resolution, then offered scar revision (SR) surgery.

Sixteen patients from November 2012 to August 2023 following PPI surgery were included; all placed by outside surgeons. No patient was lost to follow-up. Nine (56%) underwent removal prior to our evaluation. The median age at time of implantation was 36 years. Median follow-up time was 6 months. Additional patient demographics can be found in Supplementary Table S1. The most common indication for removal was distal protrusion (10/16, 63%) causing patient and partner discomfort (Supplementary Figure S1A and B). Other indications for removal were skin erosion, decreased sensation, infection, ventral curvature, and penile shortening. Following explant, 10 (63%) developed disabling dorsal curvature (Supplementary Figure S1G), 8 (50%) had penile shortening (Supplementary Figure S1F), 7 (44%) had sensory changes, 6 (38%) had localized infections, 5 (32%) had de-novo erectile dysfunction (ED), and 2 (13%) had lateral curvature (Supplementary Table S1). Disabling curve was defined as interfering with the ability to have sexual intercourse.

After explant, 10 (63%) underwent SR and one patient required a second SR. One patient developed a hematoma requiring surgical evacuation (Supplementary Table S2). During SR, severe scarring was routinely noted along the neurovascular bundles and this scar tissue was often densely adherent to the neurovascular structures from the coronal margin distally to the suprapubic area proximally. All patients who underwent SR had improvement in curvature and were able to have functional erections, although 4 patients required pharmacologic treatment for ED with 2 using oral medication and 2 using intracavernosal injection. One patient who underwent explant for skin erosion had severe penile shortening and skin loss. He underwent a skin graft for skin coverage during his SR (Supplementary Figure S1H and I). Following PPI explant, a median of 1 (range, 0-3) surgery was performed at our institution.

The PPI is a silicone sleeve placed subcutaneously along the dorsal and lateral shaft of the penis but does not extend circumferentially. A mesh is placed along the distal penile shaft just superficial to the neurovascular structures, and the sleeve is secured to the mesh with non-absorbable suture (Supplementary Figure S2C and D). The proximal silicone sleeve extends to the suprapubic area (Supplementary Figure S2A), just superficial to the dorsal surface of the penis. Since the PPI does not expand with erections, it allows a capsule to surround the sleeve over time. Typically, to remove the implant we use the same incision through which it was placed. The challenging part of removal is ensuring the entire distally placed mesh is removed and can be facilitated through counter incisions or invaginating the penis through the incision for better exposure. We feel complete removal of the mesh decreases the severity of postoperative scarring.

We found that distal protrusion of the PPI laterally near the coronal margin creating a “bat wing” appearance was the most common indication for removal. The protruding edges of the silicone sleeve are often sharp, causing patient and partner discomfort. However, those who desired removal for distal protrusion also often had other complications as shown in Supplementary Figure S1C and D. Following explant, we found that capsular contraction led to dorsal tethering during erections and penile shortening. This was sexually debilitating for patients, and in others it was completely disabling. All 10 patients in our series who underwent SR for dorsal tethering had improvement in penile curvature and were able to have satisfactory sexual intercourse. However, none reported being back to their pre-PPI status. In our experience, all patients reported having functionally normal penile length with no sexual dysfunction prior to undergoing PPI surgery. Therefore, the degree of sexual morbidity these patients experience following PPI cannot be understated.

Our report represents the first series dedicated to complications related to PPI. Juwono et al reported a case of PPI infection that occurred 8 weeks postoperatively leading to explant.⁴ This patient developed dorsolateral curvature after explant, but no additional follow-up was provided.⁴

We have learned several important lessons in managing these patients at time of scar revision. Complete excision of dense scar is critical at the time of SR which may be facilitated by multiple incisions (ie, suprapubic, penoscrotal, circumcising) and invaginating the penis to optimize exposure. It is also important to be prepared for skin grafting as demonstrated by one patient in our series.

The largest PPI series reported a complication rate of 19.3% with explant in 3.0%.¹ No patients in this series had PPI removed for poor satisfaction.¹ A recent study reported on patient satisfaction in 234 men who underwent PPI surgery over a 1-year period.² Only 100/234 (42.7%) patients responded to the surveys.² Of these men, 10.0% had device removal or replacement.² This same article also reported a post-explant rehabilitation program of massaging, stretching, and vaccum erection device use in 12 patients who desired removal but did not have infections or other adverse events.² After rehabilitation, all 12 patients reported their flaccid penis returned to preoperative length.² Neither of these studies reported on functional outcomes following PPI explant.^1,2 Although patients reported penile shortening when flaccid, in our experience patients have the greatest disability from tethering with erections, creating a functional problem due to dorsal curvature.

Our findings are important for urologists who are likely to see patients with complications following PPI since this surgery is becoming more popular. We hope our results will provide a framework for the management of this challenging problem.

Our study is limited by the retrospective design and inherent selection bias. Furthermore, our experience in a reconstructive urology practice may not be generalizable. This study was not designed to assess the overall incidence of complications following PPI. We did not obtain objective data on these patients’ penile sensation and relied on their subjective experience which may overestimate the rate of sensation changes. We also did not collect validated outcome measures regarding sexual function; however, no questionnaire is validated in this patient population.

PPI for penile enhancement can be associated with a variety of complications leading to removal. After explant, capsular contraction can result in disabling curvature and penile shortening which can be managed with SR. However, patients can experience varying degrees of sexual dysfunction despite surgical correction.

Acknowledgments

None.

Author contributions

David W. Barham (Conceptualization [Equal], Data curation [Equal], Writing - original draft [Lead], Writing - review & editing [Equal], Visualization [Equal], Jeffrey Lee (Corresponding Author, Data curation [Equal], Formal analysis [Equal], Visualization [Supporting], Writing - original draft [Supporting], Writing - review & editing [Equal], Hares Ghaziyar (Data curation [Equal], Investigation [Equal], Project administration [Equal], Visualization [Equal], Writing - original draft [Supporting], and Joel Gelman (Conceptualization [Equal], Methodology [Equal], Project administration [Equal], Supervision [Lead], Validation [Lead], Visualization [Lead], Writing - original draft [Supporting], Writing - review & editing [Equal])

David Ward Barham (Conceptualization [equal], Data curation [equal], Writing - original draft [lead], Writing - review & editing [equal]), Jeffrey Lee (Data curation [equal], Formal analysis [equal], Visualization [supporting], Writing - original draft [supporting], Writing - review & editing [equal]), Hares Ghaziyar (Data curation [equal], Investigation [equal], Project administration [equal], Visualization [equal], Writing - original draft [supporting]), Joel Gelman (Conceptualization [equal], Methodology [equal], Project administration [equal], Supervision [lead], Validation [lead], Visualization [lead], Writing - original draft [supporting], Writing - review & editing [equal]).

Funding

None declared.

Conflicts of interest

The views expressed herein are those of the authors and do not necessarily reflect the official policy or position of the Defense Health Agency, Brooke Army Medical Center, Wilford Hall Ambulatory Surgical Center, the Department of Defense, nor any agency under the U.S. Government.

Abbreviations

Ed, erectile dysfunction; ppi, penuma® penile implant; sr, scar revision; ved, vacuum erection device