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International Journal of Impotence... Jan 2022The golden standard for measuring nocturnal erections is the RigiScan Plus. It is a relatively big and uncomfortable device dating from the previous century. The aim of... (Review)
Review
The golden standard for measuring nocturnal erections is the RigiScan Plus. It is a relatively big and uncomfortable device dating from the previous century. The aim of this perspective is to conceptualize a user-friendly sensor that can be used at home for monitoring nocturnal erections. A literary search is carried out to explore the physiological changes during nocturnal tumescence and detumescence that can be measured non-invasively. Five sensor concepts are considered: plethysmography for penile arterial pulse, displacement sensor for axial length, strain gauges for radial rigidity and circumference, temperature sensors for measuring skin and cavernosal temperature, and a saturation sensor to measure hypoxia in cavernosal tissue during maximal rigidity. We think that due to practical issues, measuring penile length during sleep is impossible. Further research is recommended to investigate the remaining sensor concepts. Whether a combination of these techniques is favorable or only one of them should be studied more thoroughly.
Topics: Erectile Dysfunction; Humans; Male; Penile Erection; Penis; Sleep
PubMed: 33087873
DOI: 10.1038/s41443-020-00365-9 -
Neuromodulation : Journal of the... Dec 2023This study aimed at determining whether stimulation of sacral spinal roots can induce penile erection in cats.
OBJECTIVE
This study aimed at determining whether stimulation of sacral spinal roots can induce penile erection in cats.
MATERIALS AND METHODS
In anesthetized cats, a 20-gauge catheter was inserted into the corpus cavernosum to measure the penile pressure. Stimulus pulses (5-80 Hz, 0.2 ms) were applied through bipolar hook electrodes to sacral ventral roots alone or to combined ventral and dorsal roots of a single S1-S3 segment to induce penile pressure increases and penile erection.
RESULTS
Stimulation of the S1 or S2 ventral root at 30 to 40 Hz induced observable penile erection with rigidity and the largest increase (169 ± 11 cmHO) in penile pressure. Continuous stimulation (10 minutes) of afferent and efferent axons by simultaneous stimulation of the S1 or S2 dorsal and ventral roots at 30 Hz also produced a large increase (190 ± 8 cmHO) in penile pressure that was sustainable during the entire stimulation period. After a complete spinal cord transection at the T9-T10 level, simultaneous stimulation of the S1 or S2 dorsal and ventral roots induced large (186 ± 9 cmHO) and sustainable increases in penile pressure.
CONCLUSION
This study indicates the possibility to develop a novel neuromodulation device to restore penile erection after spinal cord injury using a minimally invasive surgical approach to insert a lead electrode through the sacral foramen to stimulate a sacral spinal root.
Topics: Male; Cats; Animals; Penile Erection; Spinal Nerve Roots; Spinal Cord Injuries; Electric Stimulation
PubMed: 35941016
DOI: 10.1016/j.neurom.2022.06.003 -
Biomolecules Dec 2021Nitric oxide (NO), the neuromodulator/neurotransmitter formed from l-arginine by neuronal, endothelial and inducible NO synthases, is involved in numerous functions... (Review)
Review
Nitric oxide (NO), the neuromodulator/neurotransmitter formed from l-arginine by neuronal, endothelial and inducible NO synthases, is involved in numerous functions across the body, from the control of arterial blood pressure to penile erection, and at central level from energy homeostasis regulation to memory, learning and sexual behavior. The aim of this work is to review earlier studies showing that NO plays a role in erectile function and sexual behavior in the hypothalamus and its paraventricular nucleus and the medial preoptic area, and integrate these findings with those of recent studies on this matter. This revisitation shows that NO influences erectile function and sexual behavior in males and females by acting not only in the paraventricular nucleus and medial preoptic area but also in extrahypothalamic brain areas, often with different mechanisms. Most importantly, since these areas are strictly interconnected with the paraventricular nucleus and medial preoptic area, send to and receive neural projections from the spinal cord, in which sexual communication between brain and genital apparatus takes place, this review reveals that central NO participates in concert with neurotransmitters/neuropeptides to a neural circuit controlling both the consummatory (penile erection, copulation, lordosis) and appetitive components (sexual motivation, arousal, reward) of sexual behavior.
Topics: Animals; Arginine; Central Nervous System; Female; Humans; Male; Nitric Oxide; Nitric Oxide Synthase; Penile Erection; Sexual Behavior
PubMed: 34944510
DOI: 10.3390/biom11121866 -
Expert Opinion on Pharmacotherapy Jun 2023Erectile dysfunction (ED) is defined as the inability to attain and/or maintain a penile erection. The first introduction of intracavernosal injection (ICI) for the... (Review)
Review
INTRODUCTION
Erectile dysfunction (ED) is defined as the inability to attain and/or maintain a penile erection. The first introduction of intracavernosal injection (ICI) for the treatment of erectile failure was in 1982 by Virag who reported the positive effects of papaverine on erectile tissue, followed by Brindley concurrently conducting research on ICI therapy with alpha-blockade. ICI remains a viable option for the treatment of ED, even after FDA approval of phosphodiesterase type 5 inhibitors in 1998. The American Urological Association (AUA) and the European Association of Urology (EAU) both recommend ICI as a second-line therapy for the treatment of ED. We herein provide an overview of the current state of ICI therapy for the treatment of ED.
AREAS COVERED
We performed a literature review from 1977-2022, using PubMed and the current AUA and EAU guidelines to discuss the current state of ICI for the treatment of ED.
EXPERT OPINION
Although other oral agents are considered first line for the treatment of ED, the current guidelines and literature demonstrate that ICI is a safe and effective option for patients; however, careful patient selection and counseling should be performed to maximize the effectiveness and safety of this ED treatment.
Topics: Male; Humans; Erectile Dysfunction; Vasodilator Agents; Alprostadil; Papaverine; Penile Erection
PubMed: 37078428
DOI: 10.1080/14656566.2023.2204189 -
The Journal of Sexual Medicine Mar 2021Penile length measurement techniques vary widely in published studies leading to inaccurate and nonstandardized measurements.
BACKGROUND
Penile length measurement techniques vary widely in published studies leading to inaccurate and nonstandardized measurements.
AIM
To review the methodology used to report data in studies evaluating penile length and provide a detailed recommendation in conducting future high-quality research.
METHODS
The MEDLINE database was searched for randomized clinical trials and open-label prospective or retrospective studies.
OUTCOMES
The panel reviewed the modality of data reporting on these specific areas: patients' age and assessment, patient position, type of measurement instrument used, penile length technique description, examination conditions, and actual examiner.
RESULTS
Overall, 70 studies investigating penile length were selected; among these, 72.85% included at least 50 patients: 16 prospective studies, 5 randomized clinical trials, and 49 retrospective cross-sectional studies. Amongst all studies, 90% reported to measure penile length by health care practitioners in clinical settings. Penile length was assessed in all 70 studies, whereas penile girth was measured in 57.14% of patients. A semi-rigid ruler was the most commonly used measurement aid to assess penile length/girth in 62.86% of studies. Penile measurements were reportedly obtained: (i) stretched state, 60%; (ii) flaccid state only, 52.68%; and (iii) during erection, 27.43%. All studies investigating the penile length in an erect state were simultaneously assessing penile length in the flaccid state. About 90% of studies investigated penile length in adults, whereas 10% were conducted in adolescents.
CLINICAL IMPLICATIONS
The use of shared methodology to assess penile length in both adults and adolescents allows more accurate and standardized measurements.
STRENGTH & LIMITATIONS
A systematic review of the published literature allowed proper data interpretation in order to provide accurate recommendations. Main limitations of the study relied on a relatively limited number of databases for the identification of potentially eligible studies.
CONCLUSION
The methodology used in studies measuring penile length should be precise and standardized in order to provide accurate data to both clinicians and researchers. Cakir OO, Pozzi E, Castiglione F, et al. Penile Length Measurement: Methodological Challenges and Recommendations, a Systematic Review. J Sex Med 2021;18:433-439.
Topics: Adolescent; Adult; Cross-Sectional Studies; Humans; Male; Penile Erection; Penis; Prospective Studies; Retrospective Studies
PubMed: 33648901
DOI: 10.1016/j.jsxm.2020.11.012 -
The Journal of Sexual Medicine Aug 2023Patients with Peyronie's disease present with a variety of penile deformities. Those with hinge effect can experience bothersome buckling of the erection and instability...
BACKGROUND
Patients with Peyronie's disease present with a variety of penile deformities. Those with hinge effect can experience bothersome buckling of the erection and instability during penetrative sex; however, the actual characteristics and clinical implications are not fully understood.
AIM
To determine the factors that cause hinge effect and to assess the role on surgical intervention.
METHODS
This retrospective review included 1223 consecutive patients who were examined by a single surgeon and had a complete penile duplex evaluation with curvature and hinge assessment. Baseline demographics, penile duplex findings, and clinical outcomes were used to assess for predictors of hinge effect.
OUTCOMES
Analyses were performed to assess preoperative predictors of hinge effect and surgical intervention.
RESULTS
Hinge effect was observed at the time of penile duplex Doppler examination in 33% of patients. Circumferential girth discrepancy at point of indentation (odds ratio [OR] 1.82; P < .001), rigidity of erection (OR, 0.82; P = .002), and degree of primary curvature (OR, 1.03; P < .001) predicted the presence of hinge effect. When controlling for rigidity, a girth discrepancy >1 cm did appear to be associated with a hinge.
CLINICAL IMPLICATIONS
Circumferential girth discrepancy >1 cm, regardless of erectile rigidity, can be associated with hinge effect.
STRENGTHS AND LIMITATIONS
As a strength, this study included the largest cohort of patients with Peyronie's disease, all of whom were examined in a rigorous and uniform manner via the same operative counseling. However, the study is limited by its retrospective nature and potential for selection and observer bias, given that the treating physician was also assessing all penile deformities as well as performing operative intervention.
CONCLUSIONS
The presence of hinge effect can cause instability of erections during penetrative sex. Multiple factors may predispose patients to a hinge effect, including the quality of erection and severity of curvature. But when controlling for rigidity, a girth discrepancy >1 cm did appear to be associated with a hinge. While many factors, such as baseline erectile dysfunction and severity of curvature, are important in determining the optimal surgical intervention, assessing for preoperative hinge effect also influenced the surgical approach.
Topics: Penile Induration; Humans; Ultrasonography, Doppler, Duplex; Penile Erection; Adult; Middle Aged; Aged; Male
PubMed: 37460401
DOI: 10.1093/jsxmed/qdad087 -
Neuropharmacology Sep 2023The cumulative evidence suggests that oxytocin is involved in the male sexual behaviors. However, no significant sexual impairments were observed in oxytocin gene...
The cumulative evidence suggests that oxytocin is involved in the male sexual behaviors. However, no significant sexual impairments were observed in oxytocin gene knock-out (KO) mice, suggesting that oxytocin is not necessary for sexual behavior in male mice. To better understand the role of oxytocin in male erection, two types of oxytocin gene KO mice were created. In the first type, the oxytocin gene was deleted in the zygote, while in the second type, the oxytocin gene was mutated in adulthood by injecting the CRISPR/Cas9 AAVs. The results showed that disrupting the oxytocin gene at either the embryonic or adult stage did not affect erection, indicating that oxytocin is not necessary for penile erection. Pharmacologically, injecting oxytocin receptor agonist Carbetocin into the VTA of the oxytocin gene KO mice still evoked penile erection. By employing the Oxt-Ires-Cre mice, we found that specifically activating oxytocinergic neurons through chemogenetics strongly induced penile erection, while inhibiting these neurons blocked the erection responses. Furthermore, ablating PVN oxytocinergic neurons abolished the male erection response. In conclusion, although the neuropeptide oxytocin is not essential for male erection, the activity of oxytocinergic neurons is required. Our results might reflect the redundancy in the central nerve system in the sense that many signals contribute to the activation of oxytocinergic neurons to evoke penile erection during sexual behaviors.
Topics: Animals; Male; Mice; Neurons; Paraventricular Hypothalamic Nucleus; Penile Erection; Receptors, Oxytocin; Oxytocin
PubMed: 37164226
DOI: 10.1016/j.neuropharm.2023.109576 -
Urologic Oncology Sep 2022With an increase in the number of cancer survivors each year, male sexual dysfunction becomes an important topic for discussion between patients and providers who treat... (Review)
Review
BACKGROUND
With an increase in the number of cancer survivors each year, male sexual dysfunction becomes an important topic for discussion between patients and providers who treat cancer. The aim of this article is to review types and mechanisms of sexual dysfunction after cancer therapy and discuss treatment options.
METHODS
Contemporary concepts regarding male sexual dysfunction after cancer treatment are reviewed and translated for clinical utility.
FINDINGS
To optimize recovery of erectile capacity after erectile dysfunction causing cancer treatments, a penile rehabilitation protocol involving phosphodiesterase inhibitors, vacuum erection device, intra corporal injections, or a combination is likely to provide some degree of clinically significant benefit. Treating hypogonadism post cancer treatment depends on the type of cancer that has been treated and patient comorbidities. Anejaculation after cancer treatments is typically not successfully or reliably treated due to the mechanism and severity of sympathetic nerve injury. Semen cryopreservation prior to cancer treatments that may injure nerve fibers essential for the ejaculatory response is highly recommended.
CONCLUSION
Management of post cancer treatment sexual dysfunction requires identification of this problem and referral to a specialist if necessary. There are several management options available that can greatly enhance quality of life in this often overlooked aspect of post cancer treatment care.
Topics: Erectile Dysfunction; Humans; Male; Neoplasms; Penile Erection; Prostatectomy; Quality of Life
PubMed: 32859462
DOI: 10.1016/j.urolonc.2020.08.006 -
Nature Reviews. Urology Dec 2019Penile wounds after traumatic and surgical amputation require reconstruction in the form of autologous tissue transfers. However, currently used techniques are... (Review)
Review
Penile wounds after traumatic and surgical amputation require reconstruction in the form of autologous tissue transfers. However, currently used techniques are associated with high infection rates, implant erosion and donor site morbidity. The use of tissue-engineered neocorpora provides an alternative treatment option. Contemporary tissue-engineering strategies enable the seeding of a biomaterial scaffold and subsequent implantation to construct a neocorpus. Tissue engineering of penile tissue should focus on two main strategies: first, correcting the volume deficit for structural integrity in order to enable urinary voiding in the standing position and second, achieving erectile function for sexual activity. The functional outcomes of the neocorpus can be addressed by optimizing the use of stem cells and scaffolds, or alternatively, the use of gene therapy. Current research in penile tissue engineering is largely restricted to rodent and rabbit models, but the use of larger animal models should be considered as a better representation of the anatomical and physiological function in humans. The development of a cell-seeded scaffold to achieve and maintain erection continues to be a considerable challenge in humans. However, advances in penile tissue engineering show great promise and, in combination with gene therapy and surgical techniques, have the potential to substantially improve patient outcomes.
Topics: Animals; Cells, Cultured; Disease Models, Animal; Humans; Male; Penile Erection; Penis; Plastic Surgery Procedures; Recovery of Function; Regeneration; Tissue Engineering; Tissue Scaffolds; Urologic Surgical Procedures, Male
PubMed: 31649327
DOI: 10.1038/s41585-019-0246-7 -
Andrologia Jun 2021Previous studies have shown that elevated levels of high-density lipoprotein (HDL) could inhibit penile erection, but the relationship between HDL and the erection of...
Previous studies have shown that elevated levels of high-density lipoprotein (HDL) could inhibit penile erection, but the relationship between HDL and the erection of the penile tip or base has not been extensively researched. We investigated the effects of HDL on erection of the penile tip and base through a cross-sectional study of 113 patients with erectile dysfunction, using a cut-off score of ≤21 on the International Index of Erectile Function-5. The following patient data were collected: nocturnal penile tumescence; blood pressure; platelet count; platelet distribution width; mean platelet volume; plateletcrit; and levels of serum glucose, total cholesterol, triglyceride, HDL, and low-density lipoprotein. Univariate and multivariate analyses were used to assess the association between HDL levels and the erection of the penile tip and base. We confirmed that HDL had a beneficial effect on penile erectile function. We also found that when the HDL level exceeded the normal range, the change in HDL had a significant effect on the penile base. In addition, our study did not find any relationship between platelet parameters and erection of the penile tip or penile base.
Topics: Cross-Sectional Studies; Erectile Dysfunction; Humans; Lipoproteins, HDL; Male; Penile Erection; Penis
PubMed: 33774838
DOI: 10.1111/and.13979