Sildenafil improves sleep-related erections in hypogonadal men: evidence from a randomized, placebo-controlled, crossover study of a synergic role for both testosterone and sildenafil on penile erections

To study the effects of sildenafil on human sleep-related erections according to the state of androgenization, we evaluated the effects of sildenafil on sleep-related erections in hypogonadal men before and during testosterone replacement treatment and in control subjects. We enrolled 24 hypogonadal men and 24 healthy men as a control group. All hypogonadal subjects had very low testosterone levels (<200 ng/dL [6.9 nmol/L]) [corrected] All subjects underwent nocturnal penile tumescence and rigidity monitoring (NPTRM) for 3 consecutive nights and were randomly assigned to consume either 50 mg of sildenafil or placebo 1 hour before bedtime on the second or third night of nocturnal penile monitoring. The hypogonadal subjects were tested twice, first without replacement treatment (H-T) and then after at least 6 months of testosterone replacement therapy (H+T). The subjects of the control group (C) were tested once. The following parameters of sleep-related erections were analyzed: total number of valid erections, total duration of both rigidity greater than or equal 70% and increase in penile circumference greater than or equal 30 mm, maximum rigidity, and maximum increase in penile circumference. NPTRM parameters were reduced in hypogonadal men before testosterone treatment (H-T+P) when compared with control subjects taking placebo (C+P). NPTRM parameters after testosterone (H+T+P) and sildenafil (H-T+S) administration were similar to that of control subjects taking placebo (C+P). When the statistical analysis was restricted to the hypogonadal men before testosterone treatment, sildenafil alone significantly increased NPTRM parameters when compared with placebo (H-T+S vs H-T+P). Testosterone restored normal erections when administered to hypogonadal subjects (H+T+P vs H-T+P); in hypogonadal men, however, the combined treatment (sildenafil plus testosterone) resulted in the maximum positive effect on NPTRM parameters. When the increase from baseline was analyzed, the effects of testosterone plus sildenafil were greater than the sum of the effects of each drug used alone. In conclusion, sildenafil administered at bedtime improves sleep-related erections in hypogonadal men, suggesting that the nitric oxide pathway may be pharmacologically enrolled and enhanced despite low serum testosterone. Furthermore, these data strongly support the idea of a synergic effect on sleep-related erections of sildenafil and testosterone.     

Sildenafil taken at bedtime significantly increases nocturnal erections: results of a placebo-controlled study

Objectives. Nighttime erections occur at all ages and contribute to the maintenance of the morphodynamic integrity of smooth muscle cells within the corpora cavernosa. This study was aimed at evaluating the effect on nocturnal erections of sildenafil versus a placebo taken at bedtime.Methods. A double-blind, crossover, placebo-controlled study design was used to examine the effects of sildenafil and placebo on sleep-related erectile activity. Thirty selected patients with erectile dysfunction (vasculogenic etiology, 22 patients [73%]; psychogenic etiology, 8 patients [27%]) were submitted to a polysomnographic recording of nocturnal erections, using a RigiScan device during 3 consecutive nights. After a first night of adaptation, the 2 following nights were used to study patients after the administration of sildenafil (100 mg) or a placebo taken at bedtime.Results. Twenty-three patients (77%) showed a significantly improved nocturnal erectile activity (according to the calculation of rigidity and tumescence activity units) after the administration of sildenafil (P <0.01), 5 patients (17%) showed comparable nocturnal erections with sildenafil and placebo, and 2 patients (6%) showed a significantly improved nocturnal erectile activity after taking the placebo (P <0.05). Overall, mean rigidity and tumescence activity values at the tip and base of the penis were significantly improved after sildenafil rather than placebo administration (P <0.001). The duration of tip rigidity greater than 60% was significantly longer during the night with sildenafil (P <0.001). Although the number of erectile episodes was greater during the sildenafil night, this did not reach statistical significance.Conclusions. In most patients with good sleep efficiency and who have erectile dysfunction, sildenafil, rather than a placebo, taken at bedtime produces a significantly improved nocturnal erectile activity. Further studies are needed to verify whether this preliminary finding may constitute the basis for the use of sildenafil as a tool for preventing erectile dysfunction.     

Comparison of the effect of sildenafil and apomorphine SL on nocturnal erections in healthy volunteers: a placebo-controlled study

OBJECTIVE: To compare the effects of sildenafil and sublingual (sl) apomorphine on nocturnal erections. METHODS: In a prospective, single-blinded, placebo-controlled at-home study we compared the effect of apomorphine sl and sildenafil on sleep-related erectile activity in 30 healthy potent volunteers (mean age, 26.4 years; range, 23-35 years; Erectile Function domain of the International Index of Erectile Function > or =26), not reporting any subjective sleep abnormality during 4 consecutive nights with rigidity monitoring (NPTR) with the RigiScantrade mark device. After the first night of adaptation, they were randomized to receive placebo or apomorphine sl 2mg or sildenafil 50mg taken at bedtime during the following 3 consecutive nights. RESULTS: Sildenafil increased the mean+/-SE number of erections, overall length of erectile events, and the time of erections with rigidity >60% at both tip and base, as compared to placebo. The same parameters were reduced after administration of apomorphine sl. Similar findings were observed with regards to Rigidity Activity Units and Tumescence Activity Units. CONCLUSIONS: Our results confirm that sildenafil taken at bedtime might increase nocturnal erectile activity also in young potent men as compared to placebo. Apomorphine sl taken at bedtime seems to have the opposite effect.     

Effect of daily sildenafil on patients with absent nocturnal erections due to pelvic fracture urethral disruption: a single‐centre experience

Erectile dysfunction (ED) is a common sequel of pelvic fracture urethral disruption. Those patients with nocturnal erections may respond favourably to sildenafil; however, little is known about the response to sildenafil in patients with absent nocturnal erections. The aim was to evaluate the response to the treatment of sildenafil 50 mg taken once daily in the patients with absent nocturnal erections. From January 2008 to December 2011, a total of 28 patients with absent nocturnal erections were evaluated. We recorded nocturnal penile tumescence and rigidity with an erectometer. If nocturnal erections were absent for three nights, patients were administrated sildenafil 100 mg at bedtime and tested again at the fourth night. Penile duplex ultrasound with intracavernous injection was performed to define the cause of ED. All patients received a daily dose of sildenafil 50 mg for 12 weeks. Response to sildenafil treatment was defined as sustained erections allowing vaginal penetration and intercourse. Twenty‐three (78%) patients completed the daily sildenafil treatment, and follow‐up was available. The nocturnal erections at the fourth night in 13 patients (46.4%) were improved. About 61.5% (8/13) reported effective response to daily sildenafil. The improvement of nocturnal erections induced by sildenafil taken at bedtime might predict the response to sildenafil taken daily.     

Sildenafil improves nocturnal penile erections in organic impotence.

We studied the effects of sildenafil on nocturnal penile erections. We prospectively evaluated 36 patients with organic or psychogenic impotence and 5 normal, potent men. All patients completed 3 sessions of consecutive nights using the RigiScan Plus device. The first two nights the patients were asked to take placebo before the session and to take 50 mg of sildenafil before the third session. In the organic impotence group the use of sildenafil induced a significant improvement in time of rigidity 60-100%, rigidity and tumescence activity unit values and rigidity and tumescence activity unit values per hour in the tip and base. In the psychogenic impotence group it caused significant improvement only in rigidity activity unit per hour in the tip. In the potent men, changes were statistically insignificant. Sildenafil improves nocturnal penile erectile activity in organic impotence. Our study shows that phosphodiesterase inhibitors can improve penile erections not induced by sexual stimulation.     

Are consecutive nightly recordings required for valid evaluation of sleep-associated erections?

We questioned the need for more than one RigiScan recording for accurate assessment of sleep-associated penile erections and determine the necessity of consecutive nightly recordings for valid evaluation of sleep-associated erections. Men complaining of erectile dysfunction (ED) and referred to RigiScan evaluation for the first time participated. Recordings were performed at the patient's home during two consecutive nights, and data on test time, number of erections, erection duration, minimal and maximal base and tip tumescence and rigidity were retrieved for both nights. Normal erectile function was defined with the recording of at least one erection (70 out of 100% tip rigidity lasting for at least 10 min during either night). The main outcome measures were RigiScan recordings. Group 1 consisted of 29 men (mean age 42.4+/-13.8 years, range 22-71) who had normal erections, all during the first night. Group 2 consisted of 26 men (mean age 48.6+/-13.5 years, range 25-70) who failed to fulfill both criteria for normal erection. In Group 2, only the values for penile base rigidity and erection duration were normal during the first night: the parameters of maximal base tumescence, tip rigidity, number of effective erections and duration of effective erections that were impaired during the first night were significantly worse (P<0.01) during the second night. The required information for the diagnosis of psychogenic ED was obtained during the first night in >50% of the participants. Men with normal erections during the first night can be spared the inconvenience and cost of re-testing. Consecutive night recording should be reserved for patients whose recorded data during the first night did not fulfill the criteria for normal erection.     

Characteristics of sildenafil erections in healthy young men

Aim： To determine the effect of sildenafil citrate on the nocturnal penile erections （i.e. time to onset, the duration of erection, and the interval between first and second erections） of healthy young men. Methods： Twenty-two potent men, 23-29 years old, were recruited for the study. All subjects completed three sessions over consecutive nights using the RigiScan monitoring device （Dacomed, Minneapolis, USA）. After a first night of adaptation, night 2 records were their baseline values, and on night 3 they received 100 mg of sildenafil citrate. Statistical comparisons were done between the second and third night data. Results： The mean time to onset of the first erection with sildenafil citrate was （34 ± 18） min, whereas it was （74 ± 24） min （P 〈 0.001） without sildenafil citrate. The number of erections observed during the first 5 h after sildenafil citrate medication was 3.6 ± 0.5 in contrast to 2.4 ± 0.5 with no medica- tion （P = 0.001）. The interval between first and second erections was shorter with sildenafil citrate： （52 ± 26） min vs. （85 ± 34） min （P = 0.01）. The duration of the last erection was statistically significantly longer with the sildenafil citrate： （64 ± 33） min vs. （42 ± 28） min （P 〈 0.01）. Conclusion： Healthy young men achieved erection within 34 min after sildenafil citrate administration, which is shorter than the 1 h interval proposed by the manufacturer. The interval between the first and second erections was shorter and the duration of the last nocturnal erection was longer.     

Effect of sildenafil on nocturnal erections of potent men

We try to evaluate the effect of sildenafil on nocturnal penile erections of potent men. We recruited 22 potent men (eight medical students and 14 urology residents) 23-29 years old into the study. A disorder-free medical and sexual history and normal erectile functions were the only inclusion criteria. All subjects completed three sessions of consecutive nights using the RigiScan Plus device. After a first night of adaptation, night 2 recordings were their baseline values whereas they received sildenafil 100 mg on night 3. We observed statistically significant improvement with regard to those NPT parameters at the nights with sildenafil: number of erectile episodes; duration of tip rigidity >60%, RAU tip, RAU base and TAU tip (P<0.005). Although the duration of erectile episodes (min) and TAU base were greater during the sildenafil night, these did not reach statistical significance. In conclusion, our study showed that sildenafil can improve nocturnal erectile quality not only in patients with erectile dysfunction as previously published but also in potent males.     

Sildenafil citrate significantly improves nocturnal penile erections in sildenafil non-responding patients with psychogenic erectile dysfunction

Effects of sildenafil citrate on nocturnal penile tumescence and rigidity (NPTR) were evaluated among sildenafil non-responding patients with psychogenic erectile dysfunction. All patients (n=30), equally divided into groups I and II, completed four consecutive nights using the RigiScan Plus device. Sildenafil citrate (50 mg) was given in the third night in group I and in the fourth in group II, whereas a placebo was given in the remaining nights. Additional patients (n=12) receiving only a placebo served as a control group. Results of NPTR recordings revealed neither significant differences between the control and non-sildenafil nights of both test groups, nor between the corresponding values of both groups (P>0.05). On the other hand, when sildenafil citrate nights of groups I and II taken together were compared with placebo nights, a significant increase of total events duration (P<0.001), average rigidity of the tip (P<0.05) and base (P<0.01), and rigidity activity unit (RAU) and tumescence activity unit (TAU) of tip and base (P<0.001) was observed. These results suggest that performance anxiety may be responsible for failure of response during awakening.     

Nocturnal tumescence: a parameter for postoperative erectile integrity after nerve sparing radical prostatectomy

PURPOSE: The exact process and time required for rehabilitation of erectile function after nerve sparing prostatectomy remain unclear to date. Different theories of the pathophysiology of postoperative erectile dysfunction are currently being discussed. In a prospective study we performed recordings of nocturnal penile tumescence and rigidity during the acute phase after nerve sparing radical prostatectomy, ie in the first night after removal of the catheter, to assess the organic penile integrity. MATERIALS AND METHODS: In 27 patients with local prostate carcinoma who had been sexually active before the intervention, we performed unilateral or bilateral nerve sparing radical prostatectomy. Preoperative sexual function of all patients was evaluated by the International Index of Erectile Function-5 questionnaire. On the day of catheter removal (postoperative day 7 to 14) an NPTR recording was performed on the following night with an erectometer (RigiScan). RESULTS: All patients had a preoperative IIEF score greater than 18. After removal of the catheter 25 of 27 patients (93%) showed 1 to 5 nocturnal rigidity increases by greater than 70% for at least 10 minutes. In a control group of 4 patients who underwent radical prostatectomy without nerve sparing, no nocturnal erections were recorded. CONCLUSIONS: NPTR recording during the acute phase after nerve sparing radical prostatectomy showed residual erectile function as early as the first night after catheter removal. These results are significant for selecting adequate pharmacological treatment for optimal therapy and rehabilitation of satisfactory erections and sexual function. In cases of early nocturnal tumescence, application of a PDE5 inhibitor can support successive organ rehabilitation. However, if tumescence does not occur, penile injection therapy is recommended.     

Recovery of erectile function after nerve-sparing radical prostatectomy: improvement with nightly low-dose sildenafil

OBJECTIVE

To evaluate the effect of low‐dose sildenafil for rehabilitating erectile function after nerve‐sparing radical prostatectomy (NSRP), as the delay to recovery of erectile function after NSRP remains under debate.

PATIENTS AND METHODS

Forty‐three sexually active patients had a NSRP; at 7–14 days after surgery they had a Rigiscan® (Dacomed Corporation, Minneapolis, MN, USA) measurement of nocturnal penile tumescence and rigidity (NPTR). To support the recovery of spontaneous erectile function, 23 patients with preserved nocturnal erections received sildenafil 25 mg/day at night. A control group of 18 patients were then followed but had no phosphodiesterase‐5 inhibitors. The International Index of Erectile Function (IIEF)‐5 questionnaire was completed 6, 12, 24, 36 and 52 weeks after NSRP.

RESULTS

Of the 43 patients, 41 (95%) had one to five erections during the first night after catheter removal. In the group using daily sildenafil the mean IIEF‐5 score decreased from 20.8 before NSRP to 3.6, 3.8, 5.9, 9.6 and 14.1 at 6, 12, 24, 36 and 52 weeks after NSRP, respectively. In the control group the respective scores were 21.2, decreasing to 2.4, 3.8, 5.3, 6.4 and 9.3. There was a significant difference in IIEF‐5 score and time to recovery of erectile function between the groups (P < 0.001), with potency rates of 86% vs 66%.

CONCLUSION

The measurement of NPTR after NSRP showed erectile function even the ‘first’ night after catheter removal. In cases of early penile erection, daily low‐dose sildenafil leads to a significant improvement in the recovery of erectile function.     

A two-part pilot study of sildenafil (VIAGRA) in men with erectile dysfunction caused by spinal cord injury

STUDY DESIGN: This was a two-part pilot study in men with erectile dysfunction (ED) due to spinal cord injury (SCI: cord level range T6-L5). Part I was a randomised, double-blind, two-way cross-over study comparing a single dose of sildenafil 50 mg or placebo. Part II was a randomised, double-blind, parallel-group evaluation of sildenafil 50 mg or placebo, taken as required (not more than once daily) approximately 1 h prior to sexual activity, over a period of 28 days. OBJECTIVES: To assay the efficacy and safety of sildenafil 50 mg and placebo. SETTING: Clinic- and home-based assessments in the United Kingdom. METHODS: A total of 27 subjects who were able to achieve at least a grade 2 erection (hard, but not hard enough for penetration) in response to penile vibratory stimulation (PVS) were recruited. In Part I, the reflexogenic response of the penis to PVS was evaluated in the clinic while in Part II, the response to treatment was assessed in the home (global efficacy. questionniare, diary). RESULTS: In Part I, 17/26 (65%) subjects had erections of >60% rigidity at the penile base (median duration 3.5 min) after sildenafil compared with 2/26 (8%) (median duration 0 min) alter placebo (P=0.0003). In Part II, 9/12 (75%) subjects on sildenafil and 1/14 (7%) subjects on placebo reported that the treatment had improved their erections (P<0.005), and 8/12 (67%) and 2/13 (15%) men, respectively, indicated that they wished to continue treatment (P<0.02). An analysis of diary data showed no difference between the groups with respect to the mean number of erections hard enough for penetration (P = 0.08). The mean proportion of attempts at sexual intercourse that were successful was 30 and 15%, respectively (P=0.21). Similarly, responses to the end-of-treatment questionnaire indicated that there were no significant differences between the groups with respect to the frequency of erections hard enough for sexual intercourse (P=0.47) or that lasted as long as the subject would have liked (P=0.11). No subject discontinued sildenafil due to adverse events. CONCLUSION: Sildenafil is an effective, well-tolerated oral treatment for ED in SCI subjects.     

Randomized, double-blind, placebo-controlled study of postoperative nightly sildenafil citrate for the prevention of erectile dysfunction after bilateral nerve-sparing radical prostatectomy

Four weeks after bilateral nerve-sparing radical retropubic prostatectomy, men with normal erectile function before surgery were randomized to double-blind sildenafil (50 or 100 mg) or placebo nightly for 36 weeks, followed by an 8-week drug-free period before assessment of erectile function. Enrollment was prematurely ceased and only 76 men completed because, assuming a placebo response rate similar to the published literature (for example, 34% in meta-analysis), the 25% response at blinded interim review suggested a lack of treatment effect. On the contrary, spontaneous erectile function (a combined score of >or=8 for questions 3 and 4 of the International Index of Erectile Function and a positive response to 'Were erections good enough for satisfactory sexual activity?') occurred in only 4% of the placebo group (n=1 of 25) versus 27% (n=14 of 51, P=0.0156, Fisher's exact test) of the sildenafil group. Nightly sildenafil administration for 36 weeks after surgery markedly increased the return of normal spontaneous erections.     

Vardenafil increases penile rigidity and tumescence in men with erectile dysfunction after a single oral dose

OBJECTIVES: To evaluate the effect of two doses of vardenafil hydrochloride on penile rigidity and tumescence while determining the pharmacokinetics. METHODS: Twenty-one patients with erectile dysfunction completed three oral single-dose regimens (placebo, 20 and 40 mg vardenafil) in a randomized, placebo-controlled, 3-way cross-over study. Penile rigidity and tumescence were measured at the base and tip with a Rigiscan for up to 2 h after dosing. The period included three 20-min repeated episodes of visual sexual stimulation. Blood samples were taken periodically up to 24 h after dosing. RESULTS: After 20 and 40 mg vardenafil, the mean duration of >60% rigidity of the base of the penis was greater than after placebo by 42.9 min (95% Cl 29.3-56.4) and by 49.3 min (95% Cl 35.7-62.9), respectively (p<0.001), and greater than after placebo by 34.6 min (95% Cl 22.1-47.1) for both doses at the tip. Additionally, significantly greater rigidity activity units and tumescence activity units were found for both doses compared with placebo (p<0.001). The plasma concentrations of vardenafil increased rapidly, with a median t(max) of about 40 min and a mean t1/2 of 4.4-4.8 h. Relative bioavailability was slightly higher for the 40-mg dose than for the 20-mg dose. The treatments were well tolerated, although slightly more adverse events, primarily headache, flushing and nasal congestion, were seen with the 40-mg dose compared with placebo. CONCLUSION: The findings confirm that vardenafil was able to generate stronger erections of longer duration than placebo under conditions of visual sexual stimulation in patients with erectile dysfunction. The pharmacokinetic, pharmacodynamic and tolerability profiles support vardenafil hydrochloride as a strong candidate for further testing as a treatment for erectile dysfunction.     

Nervenerhaltende radikale Prostatektomie mit niedrig dosiertem Sildenafil

Objective

The purpose of this study was to evaluate the effect of low-dose sildenafil (25 mg) for rehabilitation of erectile function after nerve-sparing radical prostatectomy.

Patients and methods

In a prospective study, 43 sexually active patients underwent nerve-sparing retropubic radical prostatectomy. Rigiscan® measurement of nocturnal penile tumescence and rigidity (NPTR) was carried out 7–14 days after surgery. A group of 23 patients with preserved nocturnal erections received sildenafil 25 mg/day at night to support recovery of erectile function. A control group of 18 patients underwent follow-up without PDE-5 inhibitors. Evaluation using the IIEF-5 questionnaire was performed 6, 12, 24, 36, 52 and 78 weeks after the operation.

Results

Of 43 patients, 41 (95%) showed 1–5 erections during the first night after catheter removal. In the group receiving daily sildenafil, the mean IIEF-5 score decreased or increased from 20.8 preoperatively to 3.6 at 6 weeks, 3.8 at 12 weeks, 5.9 at 24 weeks, 9.6 at 36 weeks, 14.1 at 52 weeks and 19.3 at 78 weeks after prostatectomy. In the control group, the mean preoperative IIEF-5 score of 21.2 decreased or increased to 2.4 at 6 weeks, 3.8 at 12 weeks, 5.3 at 24 weeks, 6.4 at 36 weeks, 9.3 at 52 weeks and 13.2 at 78 weeks. Statistical evaluation showed significant differences regarding the IIEF-5 score and recovery period of erectile function between the groups (p<0.001), with potency rates of 92 vs 68%.

Conclusion

The measurement of NPTR after nerve-sparing radical prostatectomy showed erectile function as early as the first night after catheter removal. In cases of early penile erections, daily low-dose PDE-5 inhibitors lead to a significant improvement/acceleration of erectile function recovery.     

Erektionsstatus nach nervenerhaltender radikaler Prostatektomie

The time lapse before recovery of erectile function after nerve-sparing radical prostatectomy is still under debate. Several pathophysiologies are postulated for postoperative erectile function rehabilitation. In prospective studies we measured nocturnal penile tumescence (NPTR) in the acute phase during the first night after catheter removal subsequent to nerve-sparing radical prostatectomy to assess the neuronal organic erectile integrity.Eighteen sexually active patients suffering from local prostate cancer underwent bilateral and unilateral nerve-sparing retropubic radical prostatectomy. All patients completed an IIEF-5 questionnaire concerning erectile function preoperatively. The transurethral catheter was removed 14 days after surgery, and nocturnal penile tumescence was measured with an erectometer (Rigi-Scan) in each patient during the following night. None of these patients received any comedication interacting with erectile function.The preoperative IIEF score was >18 in all patients. After catheter removal, 17 of 18 patients (95%) had nocturnal penile radial rigidity >70% that persisted for >10 min during one night. In a control of four patients without a nerve-sparing procedure, no nocturnal erections were recorded.The measurement of NPTR in the acute phase after nerve-sparing radical prostatectomy showed retained erectile function even during the "first" night after catheter removal. Our findings are important for an appropriate choice of pharmacotherapy for optimal recovery of erectile function. In cases of early penile erections, the cavernous nerve had been well preserved during surgery providing good neuronal integrity, and PDE-5 inhibitors can support organic rehabilitation of the corpus cavernosum. In the absence of early penile erections, the neuronal integrity of the cavernous nerve is presumed to be impaired. In this case, additional injection therapy should be chosen to support recovery of spontaneous erectile function.     

Rehabilitative therapy for erectile function after nerve-sparing radical prostatectomy

BackgroundTo date, the time course for recovery of erectile function and the effect of rehabilitative treatment after nerve-sparing radical prostatectomy (RP) is still under debate. The aim of this study was to evaluate the effect of low-dose sildenafil for rehabilitation of erectile function after nerve-sparing RP.MethodsIn a prospective, randomised study, 43 sexually active patients underwent a nerve-sparing retropubic RP. Erectometer measurement of nocturnal penile tumescence and rigidity (NPTR) was carried out 7–14 days after surgery. Some patients (23) with preserved nocturnal erections received sildenafil 25 mg/day at night to support recovery of erectile function. A control of 18 patients underwent follow up without phosphodiesterase type 5 (PDE-5) inhibitors. The International Index of Erectile Function (IIEF-5) questionnaire was given 6, 12, 24, 36, 52 and 78 weeks after operation.ResultsA total of 41 out of 43 patients (95%) showed 1–5 erections during the first night after catheter removal. In the daily sildenafil group, the IIEF-5 score decreased from a preoperative mean score of 20.8 to mean scores of 3.6 at 6 weeks, 3.8 at 12 weeks, 5.9 at 24 weeks, 9.6 at 36 weeks, 14.1 at 52 weeks and 19.4 at 78 weeks after prostatectomy. In the control group, the preoperative IIEF-5 mean score of 21.2 decreased to 2.4 at 6 weeks, 3.8 at 12 weeks, 5.3 at 24 weeks, 6.4 at 36 weeks, 9.3 at 52 weeks and 13.4 at 78 weeks. Statistical evaluation showed a significant difference in IIEF-5 score and time to recovery of erectile function between the groups (p<0.001) with potency rates of 92% vs. 68%.ConclusionsIn this study of men, the measurement of NPTR after nerve-sparing RP showed erectile function even during the “first” night after catheter removal. Sildenafil was efficacious when used in a “daily low dose” treatment and led to a significant improvement in recovery of erectile function.     

Utility of Rigiscan and papaverine in diagnosis of erectile impotence

The Rigiscan machine was used to measure nocturnal penile tumescence and rigidity in 41 men referred for evaluation of erectile impotence. In 6 patients, the Rigiscan was compared with the Tumistore and Snap-Gauge bands. Two patients achieved significant tumescence as measured by Tumistore, and 3 had significant tumescence as indicated by the breaking of two or three of the Snap-Gauge bands. None of these men achieved sufficient rigidity for intercourse as measured by the Rigiscan. Fourteen patients with organic impotence received intracorporeal injections of papaverine and were then monitored by Rigiscan. Six of the 14 were noted to have a Peyronie plaque. Of the remaining 8, 6 of these men achieved lasting erections sufficient for intercourse. The other 2 had erections that lasted ten minutes and were considered to have venous leak impotence. All patients with Peyronie disease had tumescence after papaverine injection, but in 5 the penis became rigid only at the base. Complications of papaverine injection were uncommon and minor. The Rigiscan and papaverine are useful in the diagnosis and management of erectile impotency.     

Evaluation of the effectiveness of sildenafil using questionnaire methods versus audio-visual sexual stimulation

AIM: In the present study, an audio-visual sexual stimulation (AVSS) test was used to evaluate the effectiveness of sildenafil, and the AVSS test was coevaluated with the international index of erectile function (IIEF) questionnaire. METHODS: Forty-two patients with erectile dysfunction (ED) were examined (age range, 28-73 years; mean, 51.9 +/- 11.4 years). Each patient answered the IIEF questionnaire and underwent laboratory tests and the AVSS test before administration of sildenafil. The IIEF questionnaire and AVSS test (1 h after administration of 25 mg or 50 mg sildenafil) were re-evaluated in the outpatient clinic 4 weeks later. Questions 3 and 4 of the IIEF test were used to evaluate the effectiveness of sildenafil. Sildenafil was determined to be effective if each score totalled four or five after administration. RESULTS: The rate of effectiveness of sildenafil was 52.4%, and the mean score of the IIEF 5 improved from 7.2 to 15.4 following treatment with sildenafil. The maximum and mean rigidity of the penile tip improved after the sildenafil treatment (36.1%vs 57.7% and 14.2%vs 35.8%, respectively). The maximum and mean rigidity of the penile base rose (42.4%vs 57.7% and 17.9%vs 36.8, respectively). Similarly, following treatment with sildenafil, the penile tumescence increased from 6.6 cm to 7.6 cm at the penile tip and from 7.5 cm to 8.5 cm at the penile base. CONCLUSIONS: In some ED patients the results of the IIEF questionnaire are not always consistent with those of objective evaluation, including AVSS. In these patients, combined assessment using the IIEF and AVSS might be more useful to evaluate the precise effectiveness of sildenafil, rather than relying on the IIEF results alone.     

Penile calibration for nocturnal penile tumescence studies

Artificial penile erections were created in 23 impotent patients by infusion of heparinized saline solution into the corpora cavernosa. Penile circumference as related to rigidity was accurately assessed. The increase in circumference necessary to produce erection adequate for vaginal penetration varied from 7.5 to 35 mm, whereas for maximum rigidity the penile circumference increase varied between 10 mm and 40 mm. These were then compared with the changes during nocturnal penile tumescence studies. Even though 5 patients in the series had erection greater than 15 mm, 40 per cent of them did not achieve rigidity adequate for vaginal penetration. One patient had nocturnal tumescence of only 12 mm; this, however, was an erection adequate for vaginal penetration. The approach discussed in this article may allow the rational use of portable home tumescence monitoring.