LONG-TERM RESULTS WITH VACUUM CONSTRICTION DEVICE

Michael S. Cookson and Perry W. Nidig

From the Division of Urology, The University of Texas Health Science Center, San Antonio, Texas

Patients using vacuum therapy for up to 29 Months stated an overall satisfaction of over 90% in regards to hardness, length, and circumference of their erection. The study reports of the low-cost and high success rates of Vacuum Therapy in treating Erectile Dysfunction.

ABSTRACT
From November 1985 to April 1990, 216 consecutive patients were treated with vacuum constriction device. Patients were mailed an initial questionnaire (group 1) and a long-term questionnaire (group2) at a median follow up of 3 of 29 months, respectively. Of 202 available patients 161 in group 1 (75%) and 115 in group 2 (57%) responded. Regular use of the vacuum constriction device was reported by 69% group 1 and 70% group 2 patients. Patient and partner satisfaction was 82% and 87% in group 1 and 84% and 89% in group 2 respectively. There was no significant difference between the groups with respect to regular use and patient or partner satisfaction (p>0.05). Quality of erection was evaluated for hardness, length and circumference, and with satisfaction greater than 90% in both groups. Median times per month of successful intercourse were 1, 4 and 4 for the year before, during and after obtaining the vacuum constriction device in group 2. Also, 79% of the patients in group 2 reported a statistically significant increase in the frequency of intercourse per month in the first year, which was sustained beyond the first year in 77% (p>0.01). Our results support the efficacy of vacuum constriction device for the treatment of impotence. Overall regular use rates as well as patient and partner satisfaction appear to be high. Furthermore, excellent initial results appear durable in most patients. The impact of impotence on health care dollars can be expected to grow as the number of elderly patients at high risk for erectile dysfunction continues to increase. Despite a wide variety of treatment options, there is an increasing trend toward the nonoperative management of impotence. Vacuum constriction devices have gained widespread acceptance in the management of impotence. High rates of success and patients satisfaction with the device combined with its relatively low cost and safety have helped to establish its clinical efficacy. Furthermore, scientific studies, including the work of Diederichs et al demonstrating the effects of sub atmospheric pressure on the simian penis, have given further credibility to and understanding of the use of vacuum constriction devices in the treatment of impotence. Despite its present popularity, few reports exist in the literature addressing success or patients and partner satisfaction with regard to the long-term use. Also, an attempt was made to evaluate the quantitative and qualitative impact of the vacuum constriction device on the sexual practices of those patients.

MATERIALS AND METHODS
Between November 1985 and April 1990 a total of 559 men underwent evaluation for the treatment of impotence, including a complete history and physical examination, laboratory test and more extensive studies were performed as indicated. These patients were evaluated by a single urological practice and the extent of the evaluation was at the discretion of the examiner based on the patient's goal-directed approach as described by Luc. Patients with definite symptomatic erectile dysfunction were presented a wide range of treatment options, including no treatment, vacuum restriction device, pharmacological injection therapy and surgery. Of the 559 men 266 (48%) opted to undergo evaluation for treatment with vacuum constriction device. Tumescence was maintained with 1 or more latex constriction bands. Each patient was instructed in the use of the vacuum constriction device in the office to ensure competency. After an in office demonstration 28 patients decided not to use the device and the remaining 238 patients did. At the time they obtained the device, patients were asked if they could be contacted for follow-up information and 216 (91%) consented. These 216 men formed the database for the initial follow-up. Risk factors and prior therapy are listed in table 1. Patient age ranged from 36 to 83 years, with a median age of 65. Patients were mailed an initial 3-month questionnaire by the urologist, which was returned by 161 (75%) In April 1991 a second long-term questionnaire was mailed to the original 216 patients, of whom 14 were unavailable due to death (4) and lost to follow-up (10). A total of 115 patients returned the second questionnaire, representing 57% of the available 202 patients from the initial database. The initial and long-term follow up questionnaires were identical except for an additional 6 questions in the later which primarily assessed quantitative frequency of use patterns The questionnaires addressed a wide range of subjects concerning the vacuum constriction device, including use patterns patient satisfaction, partner satisfaction, quality of erections, side effects and complications. To decrease potential bias, all results from the questionnaire were tabulated by a second independent observer. Statistical comparisons in responses between groups were then performed using a 1-tailed chi-square analysis. Students paired test was used to compare frequency of use variables among patients responding to the second questionnaire.

RESULTS
The initial questionnaire was completed and returned by 75% (161 of 216) of available vacuum constriction device users (group1) at a median follow-up of 3 months (range 2 to 6). The second questionnaire was returned by 57% (115 of 202) of available vacuum constriction device users (group2) at a median follow-up of 29 months (range 11 to 63). If a response was noted in a returned questionnaire it was not included in the analysis.

Regular use. Regular use was reported among 69% (112 of 161) group1 and 70% (80 of 115) group 2 patients with no statistically significant difference between groups (p>0.05). Of the 31% in group 1 who did not use the device regularly 22 of 51 (44%) stated they lacked the opportunity, 5 (10%) stated they no longer needed the device and 24 (47%) listed a variety of reasons, including loss of libido, poor personal (or partner) health, marital problems and dissatisfaction with the device. Of those in group 2 who did not use the vacuum constriction device regularly 17% claimed lack of opportunity, 24% no longer needed the device and the remaining patients listed a number of reasons similar to those in group 1.

Patients satisfied. In group 1, 82% of respondents stated that they were satisfied with the vacuum constriction device and believed that it had been worth the effort and expense. Also in group 1, 18% were not satisfied with the device, although 44% of them planned to continue to experiment with it. Of the group 2 patients 84% of respondents were satisfied with the vacuum constriction device compared to 16% who were not satisfied. There was no statistical difference between groups with no respect to patient satisfaction (p>0.05).

Quality of erections. Of group 1 patients 94% (150 of 160) were satisfied with the hardness of the erection compared to 92% (99 of 107) of group 2 patients. When patients were asked about the length of the penis while using the vacuum device97% (154 of 159) in group 1 were satisfied versus 91% (97 of 107) in group 2. Concerning the circumference of the penis with vacuum constriction device use, 98% of the patients 156 of 159) were satisfied in group 1, while 94% (100 of 107) reported satisfaction in group 2. Thus, overall quality of erections was greater than 90% in both groups by all 3 parameters.

Partner satisfaction. Patients were asked 3 questions about partner satisfaction with respect to appearance of the penis, function of the penis during intercourse and whether or not the partner had commented on coldness of the penis during intercourse (table 2). There was no significant difference between groups with respect to partner satisfaction (p>0.05).

Side effects related to the vacuum constriction device or constriction band. The results of the 2 questionnaires relative to side effects are listed in table 3. Major problems with penile numbness, pivoting, bruising, petechiae, as well as pain and swelling were reported by less than 10% of both groups. Furthermore, most patients either reported no change or an increased ability to achieve either climax or orgasm, with only 23% of both groups reporting a decrease in orgasm with vacuum constriction device use.

Erectile function before the vacuum constriction device. Of group 1 patients 66% (105 to 161) reported rare or no erection sufficient for intercourse before obtaining the device. An additional 19% reported achieving an erection sufficient for intercourse in less than 50% of the attempts, while 9% reported erection sufficient for intercourse in less than 50% of attempts. Only 7% reported erections satisfactory for intercourse almost every time attempted. Of group 2 patients 70% (75 of 108) of respondents reported rare or no erections sufficient for intercourse before device use. Also an additional 18% reported successful intercourse less than 50% of times attempted, 7% reported successful intercourse greater than 50% of the time and 6% reported successful intercourse almost every time attempted before obtaining the device.

Erectile function with use of the vacuum constriction device. Since obtaining the vacuum constriction device 85% (132 to 155) of respondents in group 1 report using the device to achieve an erection almost every time, 9% report using it about half the time and 5% report that they no longer need to use the vacuum. Of group 2 patients 85% (90 to 106) report using the vacuum almost every time to achieve an erection, while 5% use it about half the time and 10% report that they no longer need the device to get an erection. There was not statistical significance between groups (p>0.05).

Frequency of use of the vacuum constriction device. The second questionnaire contained additional questions pertaining to the frequency of successful intercourse attempts (times per month) in the year before, during and after the first year that the device was obtained. The median number of reported successful intercourse were 1, 4, and 4 times per month for the year before, during and after the first year of obtaining the vacuum device, respectively. Of group 2 patients79% (79 of 100) reported an increase in frequency of intercourse per week in the first year of using the device when compared to the previous year, which was statistically significant (p>0.01) Similarly, 77% reported a continued increase in frequency after 1 year of vacuum constriction device use when compared to the previous year, which was a significant difference (p>0.01). Only 6% of the patients reported a decrease in frequency of intercourse in the first year and afterward when compared to the year before obtaining the device.

Risk factors versus regular use. Patients with and without identifiable risk factors who completed the long-term questionnaire (group 2) were compared with respect to regular use. Arterial risk factors were identified in 26% (30 to 115) of the group 2 patients, of whom 86% used the vacuum constriction device regularly compared with the 64% of those without arterial risk factors, representing a statistically significant difference (p=0.018).There was no statistical difference with regular use between patients with diabetes (27), psychiatric problems (17), prostate cancer or medications with impotence side effects when compared to patients without these risk factors. There were too few patients with risk factors other than those stated to be considered of statistical significance. Patients who had been treated with a pharmacological erection program before obtaining the vacuum constriction device were compared to those who had not, and there was no statistical difference in regular use between the two subsets in group 1 or group 2 (p>0.05). Also, 4 patients who had undergone removal of a failed penile prosthesis reported regular use.

Risk factors versus patient satisfaction. Group 2 patients with identifiable risk factors were also compared to those without such factors with respect to patient satisfaction. Patients with arterial risk factors had a 93% satisfaction rate compared to 81% who had no arterial risk factors. There was an 88% patient satisfaction rate among diabetics compared with 83% among those without diabetes and an 81% satisfaction rate among patients with psychiatric risk factors compared with 85% of those without this risk factor. All patients with prostate cancer were satisfied what the device compared to 83% of the patients without prostate cancer. Of the patients on medications with known impotence side effects, 84% were satisfied with the vacuum constriction device versus 85% without such medications. There were no statistically significant differences in regard to patient satisfaction for patients with these risk factors when compared to those without identifiable risk factors (p>0.05). Patients treated with a pharmacological erection program before obtaining the vacuum constriction device were compared to those who were not, and there was no statistical difference in patient satisfaction between undergone removal of a failed prosthesis reported satisfaction with the vacuum constriction device.

DISCUSSION
The study was conducted in an attempt to obtain long-term follow-up in patients treated with vacuum constriction devices for erectile dysfunction. The initial 216 patients represent 91% of our consecutive patients evaluated and treated with a vacuum constriction device during a 53 month period initial and long- term period. Initial and long-term questionnaire were returned by 75% and 57% of available patients, respectively. This is a higher percentage of patients than the 10% sampled in a previously reported survey on the vacuum constriction device with an average use interval of 8.6 months. It is our belief that repines rates of 75% and 57% at a median follow-up of 3 and 29 months, respectively, represent a large percentage of our vacuum constriction device users and therefore, valid conclusions may be derived from the responses.

Regular use of the vacuum constriction device with short term follow-up has been previously reported. Our survey revealed that about 70% of the patients at 3 months used the device regularly, and this rate was maintained among group 2 patients with a median follow up of almost 2.5 years. These findings are similar to those of Turner et al who found that 81% of the patients used the device regularly and successfully at 6 months. Also they noted a 19% drop-out rate, with the majority of these men discontinuing use between 1 and 3 months after obtaining the vacuum constriction device successfully for 3 months after obtaining the vacuum constriction device. Similarly, Sidi et al reported a 79% rate of regular use in 100 patients with a mean follow up of 7.9 months. They reported that 21% of the patients discontinued use of the device, most of whom stopped after an average of 1.5 months. We believe that our findings, couples with observations from other studies, indicate that regular use of the vacuum constriction devise is continued by the majority of patients who use the device is continued by the majority of patients who use the device successfully for 3 months. Furthermore, most patients who stop using the device do so within the first several months, and a change in therapy is warranted for these patients.

Patient satisfaction in both or our surveys was high with an overall satisfaction rate of greater than 80% for both groups. The results are in agreement with satisfaction rates reported in other vacuum constriction device series with follow-up of less than 1 year. Our study demonstrates the durability of satisfaction rates reported in other vacuum, constriction device series with follow-up of less than 1 year. Our study demonstrates the durability of satisfaction with long term use at a median follow-up of 29 months, and there was no statistical difference between groups with respect to satisfaction (p>0.05).

Our findings of high satisfaction among vacuum constriction device users are quite different from those reported by Gilbert and Gingell who noted only a 26.7% rate of satisfactory intercourse in 12 of 45 patients with a mean follow-up of 9 months. In their study vacuum constriction devices were offered to men as a second-line treatment option after having failed intracavernosal pharmacological injection therapy. They further conclude that only a small number of patients will find the vacuum constriction device useful. Of our patients treated with prior injection therapy there was no statistically significant difference in satisfaction or regular use. The success rate of Gilbert and Gingell were also low when compared with results of other studies of patients who failed to achieve success with intracavernous injections but who failed to achieve success with injection therapy before vacuum constriction device use. Marmar et al reported results in 22 patients who received intracavernous injections but who failed to achieve a complete erection. They found that 21 of the 22 patients achieved a rigid erection with the vacuum constriction device after only partial tumescence with injection therapy alone. Allen et al found a 94% positive predictive value of a good response to papaverine in selecting patients in whom a vacuum device would be successful. They reported only 46% initial response with rigidity satisfactory for intercourse in patients using the vacuum constriction device but this was improved to 88% with regular use. Thus, it appears that satisfaction and successful use of the vacuum constriction device can be expected from patients with a history of pharmacological intracavernosal injection therapy, including those who have failed with this form of treatment.

In addition to prior therapy with a pharmacological erection program, vacuum constriction devices have proved successful in patients who failed prior penile prosthesis. Our study included 4 patients who underwent explanation of a failed penile prosthesis, and all reported satisfactory erections and regular use of the vacuum constriction device. This finding is in support of the study by Moul and McLeod who reported a 71% (10 of 14) rate of regular use and 73% rate of patient and partner satisfaction among patients in whom a penile implant has been removed before vacuum constriction device use. They noted that the quality of erection and satisfaction improved with time, possibly due to the resolution of corporeal scarring and progressively improved blood flow into corporeal sinuses.

Patient satisfaction was assessed in relation to the quality of erection produced while using the vacuum constriction device. Satisfaction in terms of hardness, length and circumference was greater than 90% in both groups. The fact that there was no significant change in satisfaction with hardness and length between the 2 groups indicates that rigidity achieved at 3 months as reproducible phenomenon, which was durable through 29 months of average use. Perhaps the most interesting finding was in satisfaction (greater than 90%) with regard to penile circumference. This finding is surprising because the vacuum constriction device produces a penile diameter greater than that attained during a normal erection with blood trapped in the extracorporeal tissues accounting for the differences.

Few reports on vacuum constriction device use contain information addressing partner satisfaction. Responses from both groups indicated greater than 85% partner satisfaction during intercourse while using the device. Turner et al reported an increase in partner arousal, ability to achieve orgasm during intercourse and overall greater partner satisfaction. Our patients were also asked whether the partner noted and coldness of the penis during intercourse. Although coldness was noted by about a quarter of partners in both groups, what which decreased partner pleasure was experienced by only approximately 10% in both groups. Nadig et al haven previously described a skin temperature change of the penis to decrease gradually an average of 0.9C (0.5 to 3.1C) in 30 minutes. This decrease is due to venous pooling of blood and partial arterial obstruction created by the vacuum constriction device at the base of the penis. This finding has been confirmed by Marmar et al who demonstrated a 70 to 75% decrease in the penile brachial artery index using penile plethysmography during application of the vacuum constriction device ring. Interestingly, the majority of patients in both groups stated that this was not a problem.

In our series numbness was thought to be a major problem in about 5% of patients in both groups. Also, bruising and petechiae were reported often in both groups. Approximately 10% of patients in group 1 and 16% in group 2 reported some pain related to the vacuum constriction device or the constriction bands. Pain with orgasm and ejaculation related to constriction of urethra at the base of the penis has been previously noted. Surprisingly, 90% of group 1 and 81% of group 2 patients reported no pain with orgasm. Also, no patients who experienced pain with orgasm in group 1 and only 3% in group2 considered this to be a major problem. Additionally, 39% of group 1 and 50% of group 2 patient reported an increased ability to achieve orgasm with the vacuum constriction device use. Witherington reported that 57% of the patients considered orgasm to be pleasant and 9% reported pain with orgasm but did not specify the degree of pain. Our series did include 23% of the patients in both groups who stated that they had a decreased ability to achieve orgasm with the use of the vacuum constriction device.

The vacuum constriction device provides constriction at the base of the penis and the corpora proximal to this are uninvolved. Thus, the penis has the potential to pivot at the base during vacuum constriction device use. Pivoting at the base of the penis was considered to be a major problem in only about 6% of the patients in both groups. Overall, it appears that in our patient population side effects were preset in only a small percentage of patients and they were considered to be a major problem in an even smaller subset.

The patients in group 2 were asked specific questions pertaining to frequency of intercourse before, during and after the first year of vacuum constriction device use. Of these patients 79% reported an increase in the frequency of successful intercourse attempts (times per month) in the first year of vacuum constriction device use. This increase was maintained beyond 1 year in 77% of group 2 patients, which is markedly different from that of Kursh et al who noted .no change in sexual desire or frequency of intercourse among 40 patients followed prospectively during 1 year of device use. Only 6% of the patients reported a decrease in frequency of intercourse in the first year f vacuum constriction device use when compared with previous year.

Patients with identifiable risk factors were compared to all patients in group 2 to evaluate whether there was a difference with respect to regular use and /or patient satisfaction. There was no statistically significant difference with the regular use among patients with diabetes, psychiatric or emotional risk factors, prostate cancer or medications with impotence side effects when compared to patients without these risk factors (p>0.05). The vacuum device appears to be a viable option in the treatment of impotence regardless if these factors. Patients with arterial risk factors (26%) demonstrated an 86% regular use versus 64% of those without arterial risk factors and this difference was significant. Therefore in patients with impotence and arterial risk factors, the vacuum constriction device can be expected to be used successfully on a regular basis. The overall satisfaction rate among group 2 patients was 84% and there was no statistically significant difference in satisfaction among the individual risk factor groups (p>0.05)

Vacuum constriction devices have proved to be an effective way to produce an erection like state in patients with erectile dysfunction. Although early success and satisfaction have been preciously reported, few studies address the long-term results in device use. Our study supports the concept that excellent results in patients and partner satisfaction as well as early regular use can be expected to continue with time. Finally, we have demonstrated a statistically significant increase in the frequency of successful intercourse attempts in 79% of the patients using the device for 1 year, which was maintained in 77% beyond the first year. Despite its limitations, the vacuum constriction device appears to be an effective and durable nonoperative treatment for erectile dysfunction, and its use should continue to increase along with its growing population.