Preoperative Erectile Function Is an Independent Predictor for Decision to Spare Cavernous Nerves During Radical Prostatectomy

Low-intensity pulsed ultrasound ameliorates erectile dysfunction induced by bilateral cavernous nerve injury through enhancing Schwann cell-mediated cavernous nerve regeneration

BACKGROUND

Cavernous nerve injury-induced erectile dysfunction caused by pelvic surgery or trauma is refractory to conventional medications and required an alternative treatment. Low-intensity pulsed ultrasound is a noninvasive mechanical therapy that promotes nerve regeneration.

OBJECTIVES

To investigate the therapeutic effect and potential mechanism of low-intensity pulsed ultrasound in the treatment of neurogenic erectile dysfunction.

MATERIALS AND METHODS

Thirty rats were randomly divided into the sham-operated group, bilateral cavernous nerve injury group, and bilateral cavernous nerve injury + low-intensity pulsed ultrasound group. The erectile function was assessed 3 weeks after daily low-intensity pulsed ultrasound treatment. The penile tissues and cavernous nerve tissues were harvested and subjected to histologic analysis. Primary Schwann cells and explants were extracted from adult rats. The effects of low-intensity pulsed ultrasound on proliferation, migration, and nerve growth factor expression of Schwann cells and axonal elongation were examined in vitro. RNA sequencing and western blot assay were applied to predict and verify the molecular mechanism of low-intensity pulsed ultrasound-induced Schwann cell activation.

RESULTS

Our study showed that low-intensity pulsed ultrasound promoted Schwann cells proliferation, migration, and neurotrophic factor nerve growth factor expression. Meanwhile, low-intensity pulsed ultrasound exhibits a stronger ability to enhance Schwann cells-mediated neurite outgrowth of major pelvic ganglion neurons and major pelvic ganglion/cavernous nerve explants in vitro. In vivo experiments demonstrated that the erectile function of the rats in the bilateral cavernous nerve injury + low-intensity pulsed ultrasound group was significantly higher than those in the bilateral cavernous nerve injury groups. Moreover, the expression levels of smooth muscle and cavernous endothelium also increased significantly in the bilateral cavernous nerve injury + low-intensity pulsed ultrasound group. In addition, we observed the higher density and number of cavernous nerve regenerating axons in the bilateral cavernous nerve injury + low-intensity pulsed ultrasound group, indicating that low-intensity pulsed ultrasound promotes axonal regeneration following cavernous nerve injury in vivo. RNA sequencing analysis and bioinformatic analysis suggested that low-intensity pulsed ultrasound might trigger the activation of the PI3K/Akt pathway. Western blot assay confirmed that low-intensity pulsed ultrasound activated Schwann cells through TrkB/Akt/CREB signaling.

CONCLUSIONS

Low-intensity pulsed ultrasound promoted nerve regeneration and ameliorated erectile function by enhancing Schwann cells proliferation, migration, and neurotrophic factor nerve growth factor expression. The TrkB/Akt/CREB axis is the possible mechanism of low-intensity pulsed ultrasound-mediated Schwann cell activation. Low-intensity pulsed ultrasound-based therapy could be a novel potential treatment strategy for cavernous nerve injury-induced neurogenic erectile dysfunction.

Restoring Quality of Life: A Comprehensive Review of Penile Rehabilitation Techniques Following Prostate Surgery

Prostate cancer is the most common type of cancer in men, and its treatment options include surgery, radiation therapy, and chemotherapy. Prostate surgery can often result in erectile dysfunction (ED), significantly impacting patients' quality of life. Penile rehabilitation techniques have been developed to restore erectile function following prostate surgery. This review discusses the different penile rehabilitation techniques available, their effectiveness, and the factors affecting their success. This paper also addresses the importance of addressing the psychological aspects of ED in these patients and the need for personalized and tailored rehabilitation plans. By providing a comprehensive understanding of penile rehabilitation techniques, this paper can assist clinicians in restoring the quality of life of patients who have undergone prostate surgery.

Cavernous Nerve Injury Resulted Erectile Dysfunction and Regeneration

Erectile dysfunction (ED) is an important cause of reduced quality of life for men and their partners. Recent studies have found that cavernous nerve injury (CNI) during prostate cancer surgery and other pelvic surgery results in medically induced CNIED in more than 80% of patients. The efficacy of first- and second-line treatment options for ED is poor. A great deal of research has been devoted to exploring new methods of neuroprotection and nerve regeneration to save erectile function in patients with CNIED, especially in patients with cavernous nerve injury after prostate cancer surgery. In addition, such as neuromodulatory proteins, proimmune ligands, gene therapy, stem cell therapy, and the current cutting-edge low-energy shock wave therapy have shown advantages in basic research and limited clinical studies. In the context of today's modern medicine, these new therapeutic techniques are expected to be new tools in the treatment of cavernous nerve injury erectile dysfunction. This article presents the main causes, mechanisms, and treatment of cavernous nerve injury erectile dysfunction and combines them with new treatment strategies.

Effect of Nerve-Sparing Radical Prostatectomy on Urinary Continence in Patients With Preoperative Erectile Dysfunction

Purpose:

We aimed to assess whether nerve-sparing radical prostatectomy (nsRP) is associated with improved recovery of urinary continence compared to non–nerve-sparing radical prostatectomy (nnsRP) in patients with localized prostate cancer and preoperative erectile dysfunction.

Methods:

A total of 360 patients with organ-confined prostate cancer and an International Index of Erectile Function score of less than 17 were treated with nsRP or nnsRP in Seoul St. Mary’s Hospital. Patients who received neoadjuvant or adjuvant androgen deprivation therapy or had a history of prostate-related surgery were excluded. Recovery of urinary continence was assessed at 0, 1, 3, 6, and 12 months. Postoperative recovery of continence was defined as zero pad usage. The association between nerve-sparing status and urinary continence was assessed by using univariate and multivariate Cox regression analyses after controlling for known predictive factors.

Results:

Urinary continence recovered in 279 patients (77.5%) within the mean follow-up period of 22.5 months (range, 6–123 months). Recovery of urinary continence was reported in 74.6% and 86.4% of patients after nnsRP and nsRP, respectively, at 12 months (P=0.022). All groups had comparable perioperative criteria and had no significant preoperative morbidities. Age, American Society of Anesthesiologists score, and nerve-sparing status were significantly associated with recovery of urinary continence on univariate analysis. On multivariate analysis, age (hazard ratio [HR], 1.254; 95% confidence interval [CI], 1.002–1.478; P=0.026) and nerve-sparing status (HR, 0.713; 95% CI, 0.548–0.929; P=0.012) were independently associated with recovery of urinary continence.

Conclusions:

nsRP, as compared to nnsRP, improves recovery rates of urinary incontinence and decreases surgical morbidity without compromising pathologic outcomes.

Prevention and management of post prostatectomy erectile dysfunction

Sexual dysfunction is common in patients with prostate cancer (PC) following radical prostatectomy (RP). Review the available literature concerning prevention and management strategies for post-RP erectile function (EF) impairment in terms of preoperative patient characteristics, intra and postoperative factors that may influence EF recovery, and postoperative treatments for erectile dysfunction (ED). A literature search was performed using Google and PubMed database for English-language original and review articles, either published or e-published up to July 2013. The literature still demonstrates a great inconsistency in the definition of what is considered normal EF both before and after RP. Thus, using validated psychometric instruments with recognized cut-offs for normalcy and severity during the pre- and post-operative evaluation should be routinely considered. Therefore, a comprehensive discussion with the patient about the true prevalence of postoperative ED, the concept of spontaneous or pharmacologically-assisted erections, and the difference between “back to baseline” EF and “erections adequate enough to have successful intercourse” clearly emerge as key issues in the eventual understanding of post-RP ED prevention and promotion of satisfactory EF recovery. Patient factors (including age, baseline EF, comorbid conditions status), cancer selection (non- vs. uni- vs. bilateral nerve-sparing), type of surgery (i.e., intra vs. inter vs. extrafascial surgeries), surgical techniques (i.e., open, laparoscopic and robotically-assisted RP), and surgeon factors (i.e., surgical volume and surgical skill) represent the key significant contributors to EF recovery. A number of preclinical and clinical data show that rehabilitation and treatment in due time are undoubtedly better than leaving the erectile tissue to its unassisted postoperative fate. The role of postoperative ED treatment for those patients who received a non-nerve-sparing RP was also extensively discussed. Optimal outcomes are achieved mainly by the careful choice of the correct patient for the correct type of surgery. Despite a plethora of potential rehabilitative approaches, they should be only considered as “strategies”, since incontrovertible evidence of their effectiveness for improving natural EF recovery is limited. Conversely, numerous effective therapeutic options are available for treating post-RP ED.

Sexual dysfunction in patients with peripheral nervous system lesions

Peripheral nervous system (PNS) disorders may cause sexual dysfunction (SD) in patients of both genders. These disorders include mainly polyneuropathies (particularly those affecting the autonomic nervous system (ANS)) and localized lesions affecting the innervation of genital organs. Impaired neural control may produce a malfunction of the genital response consisting of loss of genital sensitivity, erectile dysfunction, loss of vaginal lubrication, ejaculation disorder, and orgasmic disorder. In addition, there is often a loss of desire which actually has a complex pathogenesis, which goes beyond the mere loss of relevant nerve function. In patients who have no manifest health problems - particularly men with erectile dysfunction - one should always consider the possibility of an underlying polyneuropathy; in patients with SD after suspected denervation lesions of the innervation of genital organs within the lumbosacral spinal canal and in the pelvis, clinical neurophysiologic testing may clarify the PNS involvement. SD can alter self-esteem and lower patients' quality of life; opening up a discussion on sexual issues should be a part of the management of patients with PNS disorders. They may greatly benefit from counseling, education on coping strategies, and specific treatments.

Three-year outcomes of recovery of erectile function after open radical prostatectomy with sural nerve grafting

INTRODUCTION

Optimal oncologic control of higher stage prostate cancers often requires sacrificing the neurovascular bundles (NVB) with subsequent postoperative erectile dysfunction (ED), which can be treated with interposition graft using sural nerve.

AIMS

To examine the long term outcome of sural nerve grafting (SNG) during radical retropubic prostatectomy (RRP) performed by a single surgeon.

METHODS

Sixty-six patients with clinically localized prostate cancer and preoperative International Index of Erectile Function (IIEF) score >20 who underwent RRP were included. NVB excision was performed if the risk of side-specific extra-capsular extension (ECE) was >25% on Ohori' nomogram. SNG was harvested by a plastic surgeon, contemporaneously as the urologic surgeon was performing RRP. IIEF questionnaire was used pre- and postoperatively and at follow-up.

MAIN OUTCOME MEASURES

Postoperative IIEF score at three years of men undergoing RRP with SNG. Recovery of potency was defined as postoperative IIEF-EF domain score >22.

RESULTS

There were 43 (65%) unilateral SNG and 23 (35%) bilateral SNG. Mean surgical time was 164 minutes (71 to 221 minutes).The mean preoperative IIEF score was 23.4+1.6. With a mean follow-up of 35 months, 19 (28.8%) patients had IIEF score >22. The IIEF-EF scores for those who had unilateral SNG and bilateral SNG were 12.9+4.9 and 14.8+5.3 respectively. History of diabetes (P=0.001) and age (P=0.007) negatively correlated with recovery of EF. 60% patients used PDE5i and showed a significantly higher EF recovery (43% vs. 17%, P=0.009).

CONCLUSIONS

SNG can potentially improve EF recovery for potent men with higher stage prostate cancer undergoing RP. The contemporaneous, multidisciplinary approach provides a good quality graft and expedited the procedure without interrupting the work-flow.

Erectile Function Following Prostate Cancer Treatment: Factors Predicting Recovery

Prostate cancer represents the most common nonskin malignancy encountered in men, and the excellent long-term survival achieved in the majority of patients has allowed more attention to be given to the side effects associated with its treatment. Erectile function is one of the main concerns of patients when considering treatment options for prostate cancer. Not surprisingly, post-treatment sexual function is closely related to outcome satisfaction and has long-lasting effects on quality of life. Radical prostatectomy is currently the most commonly employed therapy for prostate cancer. Conflicting rates of erectile dysfunction have been reported after surgery, owing not only to different surgical techniques but also because of dissimilar patient populations and definitions. Providing accurate information to individual patients in regards to their chances of recuperating the ability to have intercourse after treatment is important not only because it allows patients to make informed decisions but also because it has the potential to reduce treatment dissatisfaction. This article mainly focuses on discussing predictors of erectile function after radical prostatectomy. Patient factors, surgical aspects, including comparisons between open, laparoscopic, and robotic approaches, and postoperative management issues that impact sexual outcomes are evaluated. Prediction models combining multiple factors are described. The definition and chronology of erectile function recovery and impact of sexual function on quality of life after surgery are also discussed. Teloken PE and Mulhall JP. Erectile function following prostate cancer treatment: Factors predicting recovery. Sex Med Rev 2013;1:91-103.