Advantages and limitations of sleep-related erection and rigidity monitoring: a review

A wearable adaptive penile rigidity monitoring system for assessment of erectile dysfunction

Erectile dysfunction (ED) is a prevalent type of sexual dysfunction, and continuous monitoring of penile tumescence and rigidity during spontaneous nocturnal erections is crucial for its diagnosis and classification. However, the current clinical standard device, limited by its active mechanical load, is bulky and nonwearable and strongly interferes with erections, which compromises both monitoring reliability and patient compliance. Here, we report a wearable adaptive rigidity monitoring (WARM) system that employs a measurement principle without active loads, allowing for the assessment of penile tumescence and rigidity through a specifically designed elastic dual-ring sensor. The dual-ring sensor, comprising two strain-sensing rings with distinct elastic moduli, provides high resolution (0.1%), robust mechanical and electrical stability (sustaining over 1000 cycles), and strong interference resistance. An integrated flexible printed circuit (FPC) collects and processes sensing signals, which are then transmitted to the host computer via Bluetooth for ED assessment. Additionally, we validated the WARM system against the clinical standard device using both a penile model and healthy volunteers, achieving high consistency. Furthermore, the system facilitates the continuous evaluation of penile erections during nocturnal tumescence tests with concurrent sleep monitoring, demonstrating its ability to minimize interference with nocturnal erections. In conclusion, the WARM system offers a fully integrated, wearable solution for continuous, precise, and patient-friendly measurement of penile tumescence and rigidity, potentially providing more reliable and accessible outcomes than existing technologies. Erectile dysfunction (ED) is a prevalent sexual dysfunction, and continuous monitoring of penile tumescence and rigidity during spontaneous nocturnal erections is crucial for its diagnosis and classification. However, the current clinical standard device, limited by its active mechanical load, is bulky, nonwearable, and creates pronounced interference with erections, which compromises both monitoring reliability and patient compliance. Here, we report a wearable adaptive rigidity monitoring (WARM) system (Fig. 1a) that employs a measurement principle without active loads (Fig. 1b), allowing for the assessment of penile tumescence and rigidity through a specifically designed elastic dual-ring sensor. The dual-ring sensor, comprising two strain-sensing rings with distinct elastic moduli, provides high resolution (0.1%), robust mechanical and electrical stability (sustaining over 1000 cycles), and strong interference resistance. Additionally, we validate the WARM system against the clinical standard device using both a penile model and healthy volunteers, achieving high consistency. Furthermore, the system facilitates the continuous evaluation of penile erections during nocturnal tumescence tests, with concurrent sleep monitoring, demonstrating its ability to minimize interference with nocturnal erections (Fig. 1c). In conclusion, the WARM system offers a fully integrated, wearable solution for continuous, precise, and patient-friendly measurement of penile tumescence and rigidity, potentially providing more reliable and accessible outcomes than those from existing technologies.

Shedding light on night-time erections: Determining the feasibility of nocturnal erection detection with penile transdermal light reflection of haemoglobin

Objectives

Utilizing penile saturation and temperature measurements presents a promising avenue for the development of an innovative sensor system aimed at nocturnal erection detection. This study aims to determine the feasibility of erection detection with light reflection of haemoglobin (LRH), as a precursor for penile saturation measurements, as well as penile temperature by comparison with simultaneous overnight RigiScan measurements.

Materials and Methods

This is a proof-of-concept observational study on 10 healthy volunteers with a cross sectional design. A penile transdermal haemoglobin and temperature sensor was developed to measure penile LRH through real-time monitoring with receiving photodiodes and emitting light-emitting diode (LED). Besides statistical analysis on LRH, temperature and RigiScan data, a visual assessment was done to determine detectability of changes in the LRH and temperature course during the RigiScan-annotated erections.

Results

A total of 40 nocturnal erections from 10 healthy volunteers were annotated with the RigiScan. The LRH values significantly increase during a nocturnal erection (p < 0.01) and penile temperature (p < 0.01). The largest elevation of temperature was seen in the last erection, with an increase of 0.94°C. The corrected temperature shows an increase of 1.29°C in the last erection. Furthermore, visual detectability was feasible for 80% of the erections with LRH values and 90% with the temperature output.

Conclusion

Penile LRH and temperature have the potential to serve as an alternative methodology for nocturnal erection detection compared with the currently applied circumference and rigidity measurements. This is an important step in the development of a patient-friendly and modernized tool for erectile dysfunction diagnostics. An improved sensor should be developed to allow for calculation of saturation percentage from LRH values. In combination with penile temperature measurements, this allows for conduction of further validity studies to work towards translation into clinical practice for non-invasive ED diagnostics.

'Feeling Hot': Exploring the feasibility of nocturnal erection detection through penile temperature measurements

Objectives

The observational 'Feeling Hot' study aims to evaluate the feasibility of employing overnight penile temperature measurements for the detection of nocturnal erections, thereby contributing to the advancement and modernization of a non-invasive diagnostic system for erectile dysfunction.

Subjects/Patients and Methods

In this proof-of-concept study, 10 healthy men aged 20-25 were recruited, following the methodology outlined in the 'Staying Hot' study by Torenvlied et al. Participants underwent ambulatory overnight penile temperature measurements concurrent with RigiScan recordings. Key outcome measures included baseline and peak penile temperatures during RigiScan-annotated nocturnal erections. Reference measurements of the thigh temperature were also taken to assess nocturnal temperature variations.

Results

Statistically significant penile temperature increases (p = 0.008, n = 9) were observed during nocturnal erections, with an average elevation of 1.47°C noted during the initial erections. This underscores the practical utility of penile temperature measurements in detecting erection onset. Challenges arose in accurately determining erection duration and subsequent erection onsets due to the persistence of elevated temperatures following initial erections, termed the 'Staying Hot effect'. Reference thigh temperature measurements aided in addressing this challenge.

Conclusion

Examining overnight penile temperature alongside simultaneous RigiScan recordings has yielded valuable insights into the viability of using the temperature methodology for detecting nocturnal erections. The 'Feeling Hot' study findings demonstrate significant penile temperature elevation during nocturnal erections in healthy young men, highlighting the potential of integrating this measurement methodology into the design of a modernized tool for ambulatory erectile dysfunction diagnostics. Further development of an advanced sensor system to comprehensively assess erection duration and quality is essential for enhancing clinical applicability.

'Staying Hot': Investigating the influence of overnight conditions on the penile skin temperature during male sexual arousal-A novel methodology for nocturnal erection detection

Objective

The objective of this study is to assess the impact of overnight environmental conditions on erectile penile temperature within a controlled setting, with the aim of investigating the feasibility of using temperature measurements for nocturnal erection detection in erectile dysfunction diagnostics.

Subjects/patients and methods

We conducted a proof-of-concept study involving 10 healthy male participants aged 20 to 25. The study was carried out at the Department of Urology, St. Antonius Ziekenhuis, the Netherlands. Penile temperature thermistor measurements were taken during visually aroused erections of participants in naked state and in simulated overnight condition (underwear and blankets). Main outcome variables were peak and baseline temperature during erectile periods. To minimize the impact of differences in erectile strength and duration between consecutive measurements, we applied randomization to the order of the environmental conditions.

Results

We observed a significant increase in penile temperature during erection in both the naked (p < 0.01) and simulated overnight condition (p < 0.01). The mean temperature increase was 1.70 and 0.67°C, respectively. While penile temperature returned to baseline immediately after naked erections, the 'Staying Hot effect' was noted in the simulated overnight condition measurements, where the temperature remained elevated at peak temperature for the entire 30-min period following the erection.

Conclusions

The findings from this study indicate that the penile temperature not only significantly increases during naked sexual arousal but is also detectable under simulated overnight conditions. This underscores the potential of using temperature measurements for nocturnal erection detection, representing a crucial initial step in developing a modernized, non-invasive sensor system for ambulatory erectile dysfunction diagnostics. Further research, including an overnight study, is needed to gain insights into the feasibility of utilizing penile temperature measurements for nocturnal erection detection and to assess the impact of the 'Staying Hot effect' on subsequent erection detection.

Nocturnal penile tumescence devices: past, present and future

Erectile function is an important part of men's health that can significantly impact quality of life. Naturally occurring nighttime erections experienced by men throughout their lifespan provides insight into penile health as well as overall health. Nocturnal penile tumescence (NPT) and nocturnal penile tumescence and rigidity (NPTR) devices that can non-invasively evaluate the presence and quality of erections can have valuable diagnostic and clinical utility. Early devices have several limitations that limit their current use. New, wearable devices have promising applications for the evaluation of erectile function over time. Continued advancements in this technology have the potential to render future generations of these devices as invaluable tools that are useful for both men and healthcare professionals.

Advances in physical diagnosis and treatment of male erectile dysfunction

Erectile dysfunction (ED) is the most common male sexual dysfunction by far and the prevalence is increasing year after year. As technology advances, a wide range of physical diagnosis tools and therapeutic approaches have been developed for ED. At present, typical diagnostic devices include erection basic parameter measuring instrument, erection hardness quantitative analysis system, hemodynamic testing equipment, nocturnal erection measuring instrument, nerve conduction testing equipment, etc. At present, the most commonly used treatment for ED is pharmacological therapy represented by phosphodiesterase five inhibitors (PDE5i). As a first-line drug in clinical, PDE5i has outstanding clinical effects, but there are still some problems that deserve the attention of researchers, such as cost issues and some side effects, like visual disturbances, indigestion, myalgia, and back pain, as well as some non-response rates. Some patients have to consider alternative treatments. Moreover, the efficacy in some angiogenic EDs (diabetes and cardiovascular disease) has not met expectations, so there is still a need to continuously develop new methods that can improve hemodynamics. While drug have now been shown to be effective in treating ED, they only control symptoms and do not restore function in most cases. The increasing prevalence of ED also makes us more motivated to find safer, more effective, and simpler treatments. The exploration of relevant mechanisms can also serve as a springboard for the development of more clinically meaningful physiotherapy approaches. Therefore, people are currently devoted to studying the effects of physical therapy and physical therapy combined with drug therapy on ED. We reviewed the diagnosis of ED and related physical therapy methods, and explored the pathogenesis of ED. In our opinion, these treatment methods could help many ED patients recover fully or partially from ED within the next few decades.

Wearable Soft Microtube Sensors for Quantitative Home-Based Erectile Dysfunction Monitoring

Quantifiable erectile dysfunction (ED) diagnosis involves the monitoring of rigidity and tumescence of the penile shaft during nocturnal penile tumescence (NPT). In this work, we introduce Erectile Dysfunction SENsor (EDSEN), a home-based wearable device for quantitative penile health monitoring based on stretchable microtubular sensing technology. Two types of sensors, the T- and R-sensors, are developed to effectively measure penile tumescence and rigidity, respectively. Conical models mimicking penile shaft were fabricated with polydimethylsiloxane (PDMS) material, using different base to curing agent ratios to replicate the different hardness properties of a penile shaft. A theoretical buckling force chart for the different penile models is generated to determine sufficiency criteria for sexual intercourse. An average erect penile length and circumference requires at least a Young's modulus of 179 kPa for optimal buckling force required for satisfactory sexual intercourse. The conical penile models were evaluated using EDSEN. Our results verified that the circumference of a penile shaft can be accurately measured by T-sensor and rigidity using the R-sensor. EDSEN provides a private and quantitative method to detect ED within the comfortable confines of the user's home.

The Association Between Erectile Dysfunction and Sleep Parameters: Data from a Prospective, Controlled Cohort

BACKGROUND

Many studies have reported a possible strong relationship between poor sleep quality, sleep disruption, sleep disorders, and erectile dysfunction (ED).

AIM

This study aimed to investigate the relationship between sleep quality and ED.

METHODS

Patients diagnosed with ED by the International Index of Erectile Function-5 (IIEF-5) questionnaire and 72 healthy adult men were included. Participants completed the questionnaire, underwent a detailed physical examination, and provided blood samples. All enrolled subjects then wore the Fitbit Charge 2 that monitored sleep throughout the night.

OUTCOMES

Primary outcome measures included scores on the IIEF-5, General Anxiety Disorder-7 (GAD-7) scale, Patient Health Questionnaire-9 (PHQ-9), Pittsburgh Sleep Quality Index (PSQI), and sleep monitoring parameters obtained from Fitbit Charge 2.

RESULTS

Finally, a total of 107 ED patients and 72 healthy adult men were enrolled in this study. Univariate analysis indicated that the GAD-7 (P < .001), PHQ-9 (P < .001), and PSQI scores (P < .001) significantly differed according to the presence/absence of ED. Further multiple logistic regression analysis showed that the PHQ-9 (odds ratio [OR]: 1.227, 95% confidence interval [CI]: 1.070-1.407; P = .003) and PSQI scores (OR: 1.220, 95%CI: 1.116-1.334; P < .001) were independent risk factors for ED. Analysis of objective sleep monitoring parameters showed that total sleep time (TST) (P = .001), sleep onset latency (SOL) (P = .026), deep sleep (N3) duration (P = .011) and rapid eye movement (REM) sleep duration (P < .001) were significantly differed between the 2 groups, with durations in the ED group significantly lower than those in the non-ED group. In addition, receiver operating characteristic (ROC) curve analysis indicated that the REM sleep duration had the highest area under the curve (AUC: 0.728) of all sleep parameters, with a P value < .001, a sensitivity of 72.2% and a specificity of 73.8%.

CLINICAL IMPLICATIONS

Urologists and andrologists should be aware of impacted sleep quality and depression in ED patients.

STRENGTHS & LIMITATIONS

The strength of this study is that the relationship between sleep quality and ED was assessed with both a subjective scale and an objective sleep monitoring tool. However, our study only described an association between sleep quality and ED and did not establish a causal relationship.

CONCLUSION

Sleep parameters are strongly associated with ED, indicating that poor sleep quality may increase the likelihood of ED. Wu X, Zhang Y, Zhang W, et al. The Association Between Erectile Dysfunction and Sleep Parameters: Data from a Prospective, Controlled Cohort. J Sex Med 2022;XX:XXX-XXX.

Molecular Action of Herbal Medicine in Physiology of Erection and its Dysfunction

Erection is a physiological process that involves vascular, hormonal, and nervous factors. Erectile dysfunction is one of the male sexual problems that occur globally and is reported to affect men's quality of life. Herbal plants have been widely used for disease treatment, including the problem of erectile dysfunction. This paper aims to review the molecular potential of various plants in the physiology of erection and to treat erectile dysfunction. The literature search was carried out through the Pubmed and Google Scholar databases regarding the molecular mechanisms of herbal plants and their potential involvement in the physiology of erection and overcoming erectile dysfunction. This paper focuses on six herbal plants: Panax ginseng, Ginkgo biloba, Epimedium, Black pepper, Tribulus terrestris, and Eurycoma longifolia. The six herbal plants have involvement in the erection process and have molecular potential in the treatment of erectile problems

Erectile Dysfunction and Obstructive Sleep Apnea: A Review

Erectile dysfunction (ED) is a disease with a wide scope of etiologies. Obstructive sleep apnea (OSA) is considered one of the risk factors for ED and is less studied. A growing lot of evidence show an association between OSA and ED. This study provides an updated review of the relationship between ED and OSA and the possible physiological mechanisms of ED in patients with OSA based on the current evidence. In clinical interviews, patients with ED may benefit from a sleep evaluation. However, further clinical investigations and more basic research are needed to illustrate the relationship between ED and OSA.

Wearable E-Textile and CNT Sensor Wireless Measurement System for Real-Time Penile Erection Monitoring

Erection measurements are the most important indicator of male urological disease diagnosis, treatment, and results. Rigiscan has been used widely in studies and diagnoses for nocturnal penile tumescence for evaluating erectile dysfunction by measuring the number and timing of erectile dysfunctions during sleep. However, this device has limitations such as the weight and bulk of the device and has been questioned for its role as a standard for ED Erectile Dysfunction (ED) diagnosis. In this study, we propose a real-time wearable monitoring system that can quantitatively measure the length and circumference of the penis using electronic textiles (E-textile) and carbon nanotube (CNT) sensors. The E-textile sensor is used to measure the length, circumference, and gradient with portability, convenience, and comfort. Sensors were created by coating CNTs on latex for flexibility. The CNT-based latex condom-type sensor in our proposed system shows the length, circumference, and curvature measurements with changes in resistance, and the E-textile performance shows a 1.44% error rate and a cavity radius of 110 to 300. The results of this conceptual study are for supplementary sensor development with a combination of new technologies with alternatives or existing methods for measuring erection function.

European Association of Urology Guidelines on Sexual and Reproductive Health-2021 Update: Male Sexual Dysfunction

CONTEXT

The present summary of the European Association of Urology (EAU) guidelines is based on the latest guidelines on male sexual health published in March 2021, with a last comprehensive update in January 2021.

OBJECTIVE

To present a summary of the 2021 version of the EAU guidelines on sexual and reproductive health.

EVIDENCE ACQUISITION

A literature review was performed up to January 2021. The guidelines were updated, and a strength rating for each recommendation was included based on either a systematic review of the evidence or a consensus opinion from the expert panel.

EVIDENCE SYNTHESIS

Late-onset hypogonadism is a clinical condition in the ageing male combining low levels of circulating testosterone and specific symptoms associated with impaired hormone production and/or action. A comprehensive diagnostic and therapeutic work-up, along with screening recommendations and contraindications, is provided. Erectile dysfunction (ED) is the persistent inability to attain and maintain an erection sufficient to permit satisfactory sexual performance. Along with a detailed basic and advanced diagnostic approach, a novel decision-making algorithm for treating ED in order to better tailor therapy to individual patients is provided. The EAU guidelines have adopted the definition of premature ejaculation (PE), which has been developed by the International Society for Sexual Medicine. After the subtype of PE has been defined, patient's expectations should be discussed thoroughly and pharmacotherapy must be considered as the first-line treatment for patients with lifelong PE, whereas treating the underlying cause must be the initial goal for patients with acquired PE. Haemospermia is defined as the appearance of blood in the ejaculate. Several reasons of haemospermia have been acknowledged; the primary goal over the management work-up is to exclude malignant conditions and treat any other underlying cause.

CONCLUSIONS

The 2021 guidelines on sexual and reproductive health summarise the most recent findings, and advise in terms of diagnosis and treatment of male hypogonadism and sexual dysfunction for their use in clinical practice. These guidelines reflect the multidisciplinary nature of their management.

PATIENT SUMMARY

Updated European Association of Urology guidelines on sexual and reproductive health are presented, addressing the diagnosis and treatment of the most prevalent conditions in men. Patients must be fully informed of all relevant diagnostic and therapeutic options and, together with their treating physicians, decide on optimal personalised management strategies.

Current approaches to the diagnosis of vascular erectile dysfunction

Vascular erectile dysfunction (ED) is closely related to cardiovascular events, and early diagnosis of vascular ED may be helpful to predict the occurrence of cardiovascular events and improve prognosis. At present, there are many approaches to diagnose ED, but each method has its advantages and limitations. This study retrospectively reviewed all available literature focusing on the diagnosis of vascular ED through a systematic PubMed and EMBASE search. According to the different application scenarios, the main methods for the diagnosis of vascular ED are divided into four categories. Intra-cavernous injection of vasoactive drugs is the earliest method used in the diagnosis of vascular ED and is a basic test. For the diagnosis of arterial ED, color duplex Doppler ultrasound, selective penile angiography, magnetic resonance imaging, and computed tomography are more commonly used. While for the diagnosis of venous ED, shear wave elastography, dynamic infusion cavernosometry and cavernosography are more accurate. Endo-peripheral arterial tonometry (PAT) has also been used to detect vascular endothelial function. Although various existing examinations are widely used for the evaluation of vascular ED, they still have some shortcomings, such as invasiveness, contingency, high false positive (negative) rate. New methods of long-term dynamic detection are needed.

End-to-side Somatic-to-autonomic Nerve Grafting to Restore Erectile Function and Improve Quality of Life After Radical Prostatectomy

BACKGROUND

Radical prostatectomy (RP) is recommended for the treatment of men with clinically localised prostate cancer. However, RP is associated with a high incidence of erectile dysfunction (ED), which can impact the quality of life (QoL) significantly.

OBJECTIVE

To evaluate the effectiveness of end-to-side nerve grafting surgery to restore erectile function and improve sexual QoL in men with ED after RP.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective review of a single-centre experience of nerve grafting in men with ED following RP was performed. Seventeen men had surgery between March 2015 and October 2017 in Melbourne, Australia, which fulfilled study inclusion and exclusion criteria.

INTERVENTION

Microsurgical bilateral end-to-side nerve grafts from a selective fascicular neurotomy of the femoral nerve to the penile corpora cavernosa.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Results were serially measured utilising the International Index of Erectile Function (IIEF-5) and the sexual domain of Expanded Prostate Cancer Index Composite (EPIC-26). The proportion and 95% confidence interval (CI) of men recovering sexual function following nerve grafting were determined.

RESULTS AND LIMITATIONS

All patients had ED following their RP. Median age at nerve grafting was 64yr (interquartile range [IQR] 60-66yr). Median time between nerve- and non-nerve-sparing RP, and nerve grafting was 2.4 (IQR 2.1-3.1) and 2.2 (IQR 1.7-5.1)yr, respectively. Median follow-up was 18 (IQR 15-24) mo. At 12mo after nerve grafting, 71% (95% CI 44-90%) of patients had erectile function recovery sufficient for satisfactory sexual intercourse, and 94% (95% CI 71-99%) and 82% (95% CI 57-96%) had clinically significant improvements in sexual function and reduced bother, respectively. There were two minor wound infections. Limitations include the retrospective study design.

CONCLUSIONS

End-to-side nerve grafting restored erectile function in 71% of men with ED following RP, supporting previous findings. Of the men, 94% had clinically relevant improvements in sexual QoL. We recommend multicentre implementation of post-RP nerve grafting into clinical practice with appropriate data collection to confirm its efficacy and feasibility.

PATIENT SUMMARY

We provide confirmatory evidence that end-to-side nerve grafting surgery restored erectile function and improved sexual quality of life in, respectively, 71% and 94% of men with erectile dysfunction following radical prostatectomy.

The Role of Nocturnal Penile Tumescence and Rigidity (NPTR) Monitoring in the Diagnosis of Psychogenic Erectile Dysfunction: A Review

INTRODUCTION

Nocturnal penile tumescence and rigidity (NPTR) monitoring with RigiScan was considered one of the most reliable methods to differentiate psychogenic erectile dysfunction (pED) from organic ED. However, its reliability has been questioned because of some limitations in the practice.

AIM

To present contemporary views on the role of NPTR monitoring in the diagnosis of pED.

METHOD

We performed a comprehensive review of English-language literature on NPTR and pED by a PubMed search.

MAIN OUTCOME MEASURES

Studies were included if the mechanisms of pED and nocturnal erection and the practice of NPTR monitoring in ED were the main research contents.

RESULTS

The pED results from not only psychosocial factors but also physiological changes containing central nervous abnormality. NPTR monitoring with RigiScan is still considered a useful method for the diagnosis of pED. A normal NPTR recording in a man with ED complaints probably suggests pED, whereas an abnormal recording may represent organic ED. Radial rigidity of no more than 60% is correlated well with axial rigidity, but, when it is more than 60%, the correlation between them is questioned. The consistency between NPTR and sex-stimulated erection is questionable, and the correlation of NPTR with different patient-reported outcome scoring systems is different. A normal NPTR recording in patients with ED does not necessarily mean pED, especially in patients with spinal cord injury. NPTR recordings can be influenced by depression, smoking, aging, negative dream content, and sleep disorders.

CONCLUSION

NPTR monitoring with the RigiScan is still considered a useful diagnostic tool for pED at the present stage. However, there are some disputes regarding the correlation between penile radial rigidity and axial rigidity and between NPTR and sex-related erection, as well as normative evaluation criteria for ED and the possibility of a false NPTR result, that need to be further studied. Zou Z, Lin H, Zhang Y, et al. The Role of Nocturnal Penile Tumescence and Rigidity (NPTR) Monitoring in the Diagnosis of Psychogenic Erectile Dysfunction: A Review. Sex Med Rev 2019;7:442-454.

The Early Use of Vacuum Therapy for Penile Rehabilitation After Radical Prostatectomy: Systematic Review and Meta-Analysis

Vacuum therapy has been widely used for penile rehabilitation after radical prostatectomy (RP), but its efficacy and safety are unclear. The study was to evaluate the efficacy and safety of the early use of vacuum therapy for post-RP men. Randomized clinical trials were selected according to predefined inclusion and exclusion criteria. RevMan 5.3 software was used for meta-analyses. In total, six randomized controlled trials were included with a total of 273 post-RP patients. The meta-analysis revealed that the early use of vacuum therapy could significantly improve the five-item International Index of Erectile Function and penile shrinkage in post-RP patients. Few adverse events were reported across the included studies. This review suggests that the early use of vacuum therapy appears to have excellent therapeutic effect on post-RP patients and no serious side effects were identified. Due to overall limited quality of the included studies, the therapeutic benefit of vacuum therapy in penile rehabilitation needs be substantiated to a limited degree in the future. Better methodological, large controlled trials are expected to verify the therapeutic effect of vacuum therapy in penile rehabilitation.