1072 | Evaluating the efficacy of vacuum constrictive device and causes of its failure in impotent patients Feraidoon Khayyamfar, 1,2 Seyed Kazem Forootan,1,2 Hassan Ghasemi,3 Seyed Roohollah Miri,4 Ehsan Farhadi4 Purpose: This study evaluates the efficacy of Vacuum constrictive device (VCD) and the reasons for its failure. Materials and Methods: In this cross-sectional study, 1500 men with organic erectile dysfunc- tion (ED) were enrolled from July 2003 to July 2010. The treatment efficacy was analyzed us- ing International Index of Erectile Function (IIEF) and questioning patient's partner regarding the man’s ability to perform vaginal penetration (APVP). The patient’s spouses, who responded negatively to APVP, were evaluated by a midwife for virginity, vaginal atrophy and abstained sex. Results: Totally 1310 (87.4%) patients attained full erection at first training session, remaining 188 (12.6%) were able to have full erection one week after practicing with VCD, 1419 (94.6%) were able to have successful intercourse and responded positively to APVP, 81 (5.4%) were un- able to have intercourse as stated by their wife's (negative response to APVP) that in 43 (53%), 30 (37%), and 8 (9.8%) cases the causes of failures were their wife's virginity, sex abstinence, and senile vaginal atrophy, respectively. Regarding erectile issue of IIEF scores in patients responded positive to APVP there were significant improvement from the scores of 9.3 ± 3.0 to 27.5 ± 5.0 after treatment (P < .05). Conclusion: With proper training and appropriate devices, VCD could induce sufficient erection in all patients. VCD in patients with virgin wife is ineffective, and female factors affect on success rate in VCD therapy. Keywords: erectile dysfunction; therapy; treatment outcome; vacuum; penile erection. Corresponding author: Hassan Ghasemi, MD Associate professor, Depart- ment of Ophthalmology, Medi- cal School, Shahed University, Tehran, Iran. Tel: +98 21 8896 3122 Fax: +98 21 889 63122 E-mail: ghasemi518@yahoo. com Received May 2012 Accepted April 2013 1Family Sexual Health Clinic and Research Center, Shahed University, Tehran, Iran 2Department of Urology, Shahed University, Tehran, Iran 3Department of Ophthalmol- ogy, Shahed University, Tehran, Iran 4Medical student, School of Medicine, Shahed University, Tehran, Iran SEXUAL DISFUNCTION AND INFERTILITY Sexual Disfunction and Infertility 1073Vol. 10 | No. 4 | Autumn 2013 |U R O LO G Y J O U R N A L INTRODUCTION Currently, erectile dysfunctions (ED) are managed based on the couples interactions, in which the patient and his wife’s satisfactions are the main factors for eventual therapeutic purposes.(1) American Uro- logical Association has recommended to use VCD as a safe therapeutic tools for treatment of ED since 1996.(2) Intro- duced in 1998, sildenafil is already the first line therapy for most men with ED, delegating traditional VCD therapies and injectable agents to the second line of approaches.(3,4) Patients that failed to respond or develop side effects when receiving the first and second lines of treatment are candi- date for surgical approaches.(4) Patients that are not suitable for oral medications due to ineffectiveness, development of side effect or having any contraindications may be consid- ered for intracavernosal injection (ICI) of vasodilators or VCD.(5, 6) VCD can be used successfully in treatment of ED with any kinds of etiology.(7) The VCD mechanism is due to its ability in raising the arterial inflow by the vacuum effect. The venous outflow decrease from the penis by applying a constructive rubber band while the penis is erected. The purposes of this study were 1) to evaluate the efficacy of VCD in inducing erection and to find out the causes of its failure in impotent patients, and 2) the success rates of VCD in performing vaginal penetration. MATERIALS AND METHODS Patient selection Totally 1530 men with ED due to an organic etiology for more than 3 months, who were referred for treatment to the ED clinic of the family health center Shahed University, participated in this cross-sectional study. The participants were informed of the purpose of study and gave their in- formed consent. The study protocol was based on the Dec- laration of Helsinki and approved by ethics committee of Shahed University. The diagnosis of ED was established according to the National Institute of Health statement of ED.(8) At first visit, all patients would provide their detailed medical and sexual histories, and would undergo specific physical examinations, also the level of free and total tes- tosterones would be determined if patients lack secondary sex characters. Patients with low testosterone level were of- fered hormonal replacement and were excluded from the study. Patients with psychogenic impotence (i.e. normal non-sexual erection, performance anxiety, premature ejacu- lation), who were determined by history, if required further evaluation was done by testing nocturnal penile tumes- cence (NPT), and if this showed normal patterns of noc- turnal erection, the patient were excluded from the study. Based on the patient's history and physical examination, an attempt was made to determine the etiology of impotence. Each participant had a steady co-operative female partner. Partner's were not evaluated medically before the initiation of the study but were given the opportunity and encouraged to attend, each appointment. During evaluation if patients’ wife was suspicious of having any medical or psychologi- cal problem regarding sexual performance, couple were excluded from the study. Patients using medication that af- fect sexual performance where referred to the physician or psychiatrist for modification of treatment and advice of oral drugs for treatment of ED but if it was failed or modifica- tion of drugs were not possible the patient was advised to use VCD for treatment of ED. Treatment evaluation The clinical efficacy of the various treatments was evaluat- ed using the International Index of Erectile Function (IIEF) questionnaire that is based on the scores for five separate response domains. These domains addressed as the issues of erectile function (EF) and also intercourse satisfaction (IS), orgasmic function (OF), sexual desire (SD) and fi- nally overall satisfaction (OS). Because of the absence of a validated questionnaire for Iranian population, we trans- lated the IIEF questionnaire(2) in to the Persian. The entire questionnaires were completed after full explanations to the patients by urologist. The ultimate score for each field was calculated as the summation of the scores attained for each individual question in that field or domain. In addition to the IIEF questionnaire, the men were asked about the state of their wife's virginity by answering yes or no; moreover all patients’ partner were requested to respond either yes or no, regarding the men’s ability to perform vaginal penetra- tion (APVP). Vacuum and Impotence | Ghasemi et al 1074 | Treatment method All Patients were trained by an urologist who was expert in VCD as well as watching an instructional locally pro- duced video for VCD (HAMRAH medical group, Tehran, IRAN). The manufacturer had provided vacuum device cyl- inders and constrictive rings of different sizes that could be adapted to the patient’s penis sizes. Furthermore, if patient did not achieve full erection that was considered by the pa- tient and the physician to be unsatisfactory for penetration at the first visit, he was advised to practice with VCD for one week by putting penis inside VCD cylinder, producing negative vacuum pressure until achieving full erection and maintaining it for 20 minutes three times a day without us- ing single constrictive ring.(6,9,10,11,12) Technical advice was made available by revisiting the patients on a daily basis if demand. Study protocol The IIEF questionnaire was administrated before the treat- ment, and after 15 times using of this method during one year of follow up. Patients were asked for any bruising in- jury or skin changes sufficient to decrease the number of the times using the device, or stop using of the treatment altogether. If there was a failure the patient was advised to revisit in the clinic with his partner for re-valuation, all of the patients were examined by both an urologist and a mid- wife for the status of wife's virginity, and vaginal atrophy. Statistical Analysis The scores of IIEF in each domain compared with VCD before and after treatment. To determine the changes in re- sponse to VCD treatment we used Chi square and paired T test using the statistical package of social science (SPSS Inc, Chicago, Illinois, USA) version 16. The P value less than .05 was considered statistically sig- nificant. The use of VCD for APVP was also assessed by asking the patients’ spouses to respond either positive or negative. Using mean statistics values, these responses were compared before and after treatment with VCD regarding various response domains. The patients responses’ were compared with each other in domains of EF, IS, OF, SD, and OS. The ultimate score for each domain was calculated as the summation of the scores attained for each individual query in that domain. The data were presented as means and percentage as summary statistics. Finally the positive and negative responses to APVP question were compared with each other in patients’ with virgin wife regarding abridge six items of EF post treatment to assess the exact difference induced by VCD on the erectile function of these patients. RESULTS A total of 1530 referred patients with ED were enrolled in this study. Age range was between 22 to 85 years (mean ± SD, 48.2 ± 12.5). Thirty patients out of 1530 cases were excluded from the study. Of those, 15 patients reported that VCD was socially inconvenient. Thirteen cases discontin- ued their treatment because of psychological discomfort in performing sex and attempting sexual intercourse less than 15 times using their devices during one year of fol- low up and were excluded from the study and referred to psychologist. The two remainder patients were unable to get full erection in clinic due to the history of prolonged priapism and severe corporal fibrosis and therefore were excluded from the study. VCD was able to induce full erec- tion in clinic during initial training and we didn’t have any failure in inducing and maintaining erection in all patients. Because of attaining full erection in all patients, we didn’t separate the patients to age subgroups. Sum of 1500 pa- Sexual Disfunction and Infertility Table 1. IIEF scores before and after the treatment with vacuum constrictive device. OS (P value) S Des (P value) OF (P value) IS (P value) EF (P value) Stage of treatment 3.9 ± 1.7 6.3 ± 1.9 5.6 ± 2.4 6.7 ± 2.4 9.3 ± 2.9 Pretreatment (SD) 8.6 ± 1.5 (P < .0001) 7.4 ± 3.1 (P < .0001) 11.1 ± 1.2 (P < .0001) 11.1 ± 1.2 (P < .0001) 26.6 ± 4.9 (P < .0001) Post-treatment (SD) Key: IIEF, international index of erectile function; EF, erectile function; IS, intercourse satisfaction; OF, orgasmic function; S Des, sexual desire; OS, overall satisfaction; SD, standard deviation. 1075Vol. 10 | No. 4 | Autumn 2013 |U R O LO G Y J O U R N A L tients were evaluated in this study. Those patients with pe- nile bruising were advised to stop using VCD for 2 weeks. Full erection was achieved on the first training session in 1310 (87.4%) patients, but 188 (12.6%) of the patients were able to have full erection one week after practicing with VCD. Of 1500 patients a total of 1419 (94.6%) were able to have successful intercourse and responded positively to APVP (Table 1). In different domains of EF, IS, OF, SD and OS scores, all patients with positive APVP had improvement compared with the pretreatment scores (P < .05). Eighty one patients (5.4%) were unable to have intercourse as stat- ed by their wife, (responded negatively to APVP) in spite of having full erection on clinical trainings. Among these pa- tients 43 (53%) were having virgin wife, 30 patients (37%) had histories of sexual abstinence (sex abstinence defined as couples whom had not having intercourse with full rigid penis for more than six months that had lead to vaginal lu- men narrowing) and a number of 8 (9.8%) patients had se- nile vaginal atrophy. Regarding the technical problems, 78 patients needed retraining sessions. In addition, 50, 20, and 5 patients needed repeated 2, 3 and 4 training sessions by the urologist, respectively, of them, 3 patients needed their wives attendance and training due to their husband's illit- eracy and physical inadequacy. Table 1 demonstrated the IIEF score before and after VCD therapy in all of the patients. Table 2 summaries the IIEF scores of patients with APVP positive in which there were significant improvement between pretreatment and post treatment regarding various issues of erectile function (P < .05). IIEF scores of patients with APVP negative whom were not having significant improvement compared with pretreatment, except EF in which sum score of domain was improved from 9.2 ± 1.5 pretreatment to 13.77 ± 3.03 (P < .05). Table 3 shows that VCD can induce full erection in all patients. IIEF Q1 and IIEF Q2 have similar domains score in men with virgin wife and men whom their wife weren't virgin. But regarding IIEF Q3, Q4, Q5, and Q15 patients whom were not having virgin wife had improve IIEF do- mains as compared to pretreatment. Comparing IIEF scores erectile function issue among APVP negative and APVP positive after treatment that regards various domains, we find that it was similar at IIEF Q1 and Q2 (P > .05). In both group but there were significant differences at IIEF Q3, Q4, Q5 and Q15 (P < .05). DISCUSSION Previous studies on VCD had demonstrated variable success rates. Some studies have shown high success rates(4,6,7,10,13,14,16,17) but other studies have come up with lower success rates.(15,18,19,20,21) Some researchers have agreed those success rates are highly affected by the degree of the training.(6, 22) The reason for the wide range in suc- cess rates in different studies was applying of the different evaluation criteria. For example, in Moulmein’s study(23) their criterion for success was the ability to attain erection. Table 2. IIEF scores of patients according to ability to perform vaginal penetration. Response to APVP Age, years Treatment period Patients (no.) EF P value IS P value OF P value S Des P value OS P value APVP Positive 23-88 (Mean = 49) Pretreatment (SD) 1419 9.3 ± 3.0 6.7 ± 2.4 5.6 ± 2.1 1.8 ± 6.3 3.9 ± 1.8 Post- treatment (SD) 27.3 ± 5.1 (P < .0001) 11.3 ± 1.2 (P < .0001) 6.3 ± 1.8 (P < .0001) 7.5 ± 3.2 (P < .0001) 8.9 ± 1.5 (P < .0001) APVP Negative 22-55 (Mean = 34) Pretreatment (SD) 81 9.2 ± 1.5 7.6 ± 2.7 5.3 ± 2.3 6.4 ± 3.3 4.4 ± 1.6 Post-treatment (SD) 13.77 ± 3.03 (P < .001) 7.2 ± 2.7 5.2 ± 2.3 6.3 ± 2.1 4.1 ± 1.2 Key: IIEF, international index of erectile function; APVP, ability to perform vaginal penetration; EF, erectile function; IS, intercourse satisfaction; OF, orgas- mic function; S Des, sexual desire; OS, overall satisfaction; SD, standard deviation. Vacuum and Impotence | Ghasemi et al 1076 | In Cookson and Nadig’s study,(14) long-term use of VCD was taken as a criterion of success, and in Broderick and colleagues’(9) study patient satisfaction was considered for evaluation and success. In our study the criterion for suc- cess was patient’s ability for vaginal penetration along with fully erected penis. Moreover our success rate were higher than the other studies, because of the using proper sizes of VCD cylinders or constrictive rings and proper training of the patients by an expert urologist that was also advised in other studies.(10,22) Our research was a first study that noticed the importance of female factor in VCD failure. Denil and colleagues(24) also reported 93% of their patients obtained erection, but only 83% of them were having sufficient rigidity for vagi- nal penetration, and we think that it was not only quality of penis rigidity, but also the vaginal resistivity that was the main cause of failure for their patients whom were un- able to have vaginal intercourse despite having erections. In Wada and colleagues’ study25 they used locally manufac- tured VCDs and their ability to induce successful erection was hundred percent (in 20 patients) of their patients which is similar to finding in our study, having a same finding on a much larger scale. In Earle and colleagues study,(26) 81% of patients abandoned the VCD that is quite high, but in our clinic VCD was found acceptable by most of the patients who were advised; it might be due to the good explanation of different therapeutic methods, the proper training of the patients, solving side effects, explaining their advantages, disadvantages to the patients and their wife. Nadig and col- leagues(7) mentioned that one of his patient’s penile rigidity began to decrease five to ten minutes after the sexual activi- ty, even though it would not change over a thirty-minute pe- riod that once originally tested in the laboratory. In Gilbert and Gingell’s study although 38 patients were able to obtain an erection-like state using a vacuum constriction device, only 12 were able to enjoy satisfactory sexual intercourse. (18) In a retrospective study, Sidi and colleagues concluded that the pain, inconveniency, and early loss of rigidity were the most important causes for dissatisfactions.(12) Our find- ings indicate that vaginal resistance causes early loss of ri- gidity and failure to penile entrance during the intercourse. In this research, 43 patients had virgin wife that were not noticed in any of the studies, this may be due to the fact that our clinic has known as is a referral center, and virginity is culturally preserved in unmarried ladies in our country. As we attained hundred percent erections in our study so we believe the effect of VCD on quality of erection is not af- fected by the etiologies e.g. arteriogenic,(13) corporeal veno- occlusive dysfunction(21) and diabetic ED(27,28) which was mentioned in other studies as well. Comparing IIEF Erectile function issue among APVP nega- tive and APVP positive before and after the treatment that including various domains, we found that it was similar in IIEF Q1, Q2 in both groups but there was significant differ- ences for IIEF Q3, 4, 5 that showed loose of erection de- spite having full tumescence before the intercourse which is believed to arise from severe vaginal resistance in patients with narrow vagina (virginity, abstinence sex, and vaginal atrophy) causing an escape of blood from the corpus caver- nosa through the constrictive ring at the penis base. Moreo- ver, patients whom wife responded negative to APVP had lower scale in IIEF Q15 too. In this study we encountered with some limitations. The pa- tients’ spouses that had positive response to APVP were not advised to admit the clinic if they were having successful sexual intercourse. Because they have not examined by the midwife, we could not provide any comments regarding the significance of the vaginal atrophy or abstinence in VCD Sexual Disfunction and Infertility Table 3. Response to the abridged six-item (erectile function) version of the IIEF questionnaire comparing the APVP positivity and APVP negativity in all patients, post-treatment among patient having virgin wife. IIEF questionnaire APVP Positive APVP Negative P value IIEF Q1 (SD) 4.71 ± 0.86 4.60 ± 0.84 .255 IIEF Q2 (SD) 4.60 ± 0.96 4.75 ± 0.75 .088 IIEF Q3 (SD) 4.10 ± 0.86 1.02 ± 0.23 < .001 IIEF Q4 (SD) 4.61 ± 0.86 1.11 ± 0.35 < .001 IIEF Q5 (SD) 4.76 ± 0.74 0.86 ± 0.21 < .001 IIEF Q15 (SD) 4.52 ± 0.73 1.43 ± 0.65 < .001 Total (SD) 27.3 ± 5.01 13.77 ± 3.03 < .001 Key: IIEF, International index of erectile function; Q, Question; APVP, abil- ity to perform vaginal penetration; SD, Standard deviation. 1077Vol. 10 | No. 4 | Autumn 2013 |U R O LO G Y J O U R N A L failure. This issue could be of importance for future investi- gations. Also due to significance of the issue we suggest to validate a questionnaire for Iranian population. Comparing the patients' partner for the virginity, none of the partners responding positive to APVP were virgin. On the other hand, all patients with virgin wife were unable to have sexual intercourse with their partner that means vaginal tightness could directly affect the success of the in- tercourse in patients using VCD. Therefore, we could con- sider the presence of virginity as one of the major factors in VCD failure. We tried to suggest non-invasive treatments to our patients and believe careful training decreases the side effects, and increase the effectiveness of VCD. Handling problems regarding its failure can prevent more invasive alternative therapy. Patients with bleeding disorders or those on anticoagulation therapy are considered at high risk to develop petechiae, echymosis or hematoma.(6) In our study we had 53 patients whom were using anticoagulant therapy and we did not ob- served any major side effects to be developed in them, it was shown that the risk did not exceed that of the general population. All patients whose wife accepted vaginal, dilatation could take advantage of VCD for the sexual intercourse. Mecha- nisms of erection induced by VCD are entrapment of blood in corporal sinusoids.(29) Most probably practicing with VCD in initial steps would be of great help on its effective- ness.(30) CONCLUSION The VCD device could induce sufficient effective erec- tion in all patients provided that using proper training and appropriate vacuum cylinders size and constrictive rings. Moreover; using VCD in patients with virgin wife is inef- fective, and female factors could affect the success rate in VCD therapy. ACKNOWLEDGMENTS Kind thanks to Shahed University due to logistical supports. Also we kindly appreciate Mrs. Khadijeh Mohammadi the midwife, for her help in patients’ partner examination. CONFLICT OF INTEREST Dr. F Khayyamfar owns patent on the VCD described in this report. 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