Evaluation of the effectiveness of sildenafil using questionnaire methods versus audio-visual sexual stimulation
Blackwell Science, LtdOxford, UKIJUInternational Journal of Urology0919-81722005 Blackwell Publishing Asia Pty LtdMarch 2005123369373Original ArticleEvaluation of sildenafil using audio-visual sexual stimulationT Suetomi
International Journal of Urology
Evaluation of the effectiveness of sildenafil using
questionnaire methods versus audio-visual
TAKAHIRO SUETOMI, FUMIYASU ENDO, HITOSHI TAKESHIMA ANDHIDEYUKI AKAZA
Department of Urology, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Japan
: 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.
: 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.
: 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
tively). 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.
: 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.
audio-visual sexual stimulation, erectile dysfunction, sildenafil.
questionnaires are widely used as tools to evaluate theeffectiveness of sildenafil.1 However, questionnaire tests
Since March 1999, sildenafil citrate (Viagra) has been
available in Japan and it has become the first choice for
At the Department of Urology, University of
treatment of erectile dysfunction in many cases. The
Tsukuba, Tsukuba, Japan, sildenafil has been prescribed
international index of erectile function (IIEF) and other
to patients with erectile dysfunction since 1999, in addi-tion to conventional treatment measures.
To evaluate the effectiveness of sildenafil, the
audio-visual sexual stimulation (AVSS) test is given to
Correspondence: Takahiro Suetomi MD, Department of
patients with informed consent, in addition to the IIEF
Urology, Institute of Clinical Medicine, University ofTsukuba, 1-1-1 Tennodai, Tsukuba-city, Ibaraki 3058575,
We report here the usefulness of the AVSS test in
Received 23 January 2004; accepted 24 August 2004.
evaluating the effectiveness of sildenafil.
A commercially available virtual glasses set, EyeTREK(FMD-011F, Olympus Optical, Tokyo, Japan) was used
A total of 42 men with erectile dysfunction (ED) who
to stimulate the patients visually for the AVSS test.
visited our clinic between May 1999 and May 2003 were
These glasses have tri-dimensional viewing capability,
are equipped with stereophonic headphones and can
The mean age of the patients was 51.9 ± 11.4 years
keep the patient’s feelings away from the surrounding
(range, 28–73 years), and the mean duration of erec-
environment. The 30-min erotic video was shown indi-
tile dysfunction was 13.9 ± 11.7 months (range, 1–
vidually to each patient in a dark and silent room. A
48 months). All patients had a sexual partner and
different movie was used for each AVSS test. The penis
had not received any previous treatment for erectile
of the patient was connected to the RigiScan-Plus device
according to the instruction manual, and the device
The etiology of ED was determined by anamnestic
automatically determined the baseline penile rigidity
documentation, medical history, and a nocturnal penile
and tumescence for the first 15 min, and then stimulated
tumescence (NPT) test using a snap-gauge (Timm Med-
rigidity and tumescence for the next 30 min. In this
ical Technologies, Eden Prairie, MN) at home (Table 1).
study, manual stimulation of the penis was prohibitedduring the session.
All patients underwent baseline evaluation, includingvital signs, the IIEF questionnaire, serum concentrations
Data analysis was performed with the Wilcoxon signed-
of hormones (testosterone, luteinizing hormone [LH],
rank test. Results were considered statistically signifi-
follicle stimulating hormone [FSH], prolactin, and estra-
diol) and the AVSS test with a RigiScan-Plus. Twenty-five milligrams of sildenafil was administrated to allpatients without contraindication for the first treatment.
If the ED was not sufficiently improved with 25 mg ofsildenafil, then 50 mg of sildenafil was prescribed.
Results of questionnaire
Of the 42 patients, 22 (52.4%) reported effective resultsin assessment with the IIEF. There was no significant
Patients revisited our clinic 4 weeks after the sildenafil
difference in age between the effective group and the
administration and answered the IIEF questionnaire and
ineffective group (53.6 vs
51.0 years old). Ten (55.6%)
took the AVSS test (1 h after administration of 25 mg
of 18 patients with organic erectile dysfunction reported
or 50 mg of sildenafil). Questions 3 (Q3, ability to
that sildenafil was effective. Fifty percent of those (seven
achieve an erection) and 4 (Q4, ability to maintain an
of 14) with functional erectile dysfunction and 50%
erection) of IIEF were used to evaluate the effectiveness
(five of 10) with mixed etiological erectile dysfunction
of sildenafil according to the definition of the National
reported that it was effective in the IIEF evaluation.
Institute of Health (NIH).2 If each score was four or
No significant difference was found among the three
higher after administration, sildenafil was determined to
groups. For other questions, the average scores were
1.0–2.0 higher than the pretreatment scores. The meanscore of the IIEF-5 for all patients significantly improvedfrom 7.2 ± 4.6 to 15.4 ± 6.6 (Table 2). The mean IIEF-
5 score was elevated from 7.9 ± 4.9 to 19.8 ± 2.8 in theeffective group (22 patients), and from 6.4 ± 4.3 to
10.5 ± 6.0 in the ineffective group (20 patients).
Results of the AVSS test
With AVSS, the maximum rigidity improved from
36.1% to 57.7% at the penile tip and from 42.4% to
57.7% at the penile base for all cases. In the effective
Evaluation of sildenafil using audio-visual sexual stimulation
Mean of the IIEF-5 score before and after administration of sildenafil
Maximum rigidity before and after administration of sildenafil
Mean rigidity before and after administration of sildenafil
Mean of the tumescence before and after administration of sildenafil
group, the maximum rigidity was elevated from 51.5%
Penile tumescence increased from 6.6 cm to 7.6 cm
to 81.2% at the tip and from 59.3% to 77.2% at the base.
at the penile tip and from 7.5 cm to 8.5 cm at the penile
However, lower rates of increase were found for the
base, overall. In the effective group, penile tumescence
increased from 6.8 cm to 8.4 cm at the tip and from
The mean rigidity improved from 14.2% to 35.8% at
7.9 cm to 9.3 cm at the base. In the ineffective group,
the penile tip, and from 17.9% to 36.8% at the penile
penile tumescence virtually did not respond to the treat-
base overall. In the effective group, the mean rigidity
improved from 22.7% to 52.5% at the tip and from
The AVSS test can also evaluate the rigidity activity
28.4% to 53.7% at the base. The rates of increase for
unit (RAU) and tumescence activity unit (TAU), which
the effective group were also higher than those of the
represent the maintenance of erection. The average
RAU for all cases improved from 2.8 to 7.6 at the
penile tip and from 3.3 to 7.8 at the penile base. The
Adverse reactions were observed in three patients in the
average RAU of the effective group was increased
25 mg sildenafil group. Two patients had flushing, and
from 4.0 to 10.1 at the tip and from 4.8 to 10.6 at the
The average TAU for all cases improved from 1.8 to
5.5 at the penile tip and from 2.4 to 5.7 at the penile
base. In the effective group, TAU increased from 2.5 to7.8 at the tip and from 3.3 to 7.5 at the base. RAU and
Sildenafil citrate, which was approved for the oral treat-
TAU responded to sildenafil treatment more highly in
ment of erectile dysfunction in Japan in 1999, has had
the effective group than in the ineffective group
a great influence on the management of erectile dys-
function. It has become the first choice for the treatment,based on the ‘goal directed approach’, proposed by Lue
Serum hormone levels
Clinicians prescribe sildenafil for almost all patients
The mean baseline serum hormone levels (standard val-
with erectile dysfunction, after taking a detailed medical
ues) are as follows: testosterone 435.7 (250–1100) ng/
history and performing physical examinations and
blood tests. The effectiveness of sildenafil is generally
8.2) mIU/mL, prolactin 6.5 (1.5–9.7) ng/mL, and estra-
assessed using questionnaire tests including the IIEF-5.4
Because the IIEF is a simple, reliable and inexpensive
In two patients, a low serum concentration of total
tool for assessment of erectile function, it is widely used
testosterone was observed. These two patients consisted
for the diagnosis of erectile dysfunction and evaluation
of one sildenafil effective and one ineffective case. No
of the treatment. However, because it is a self-evaluation
statistical correlation between the effective rate and
method, it is not always objective. Furthermore, it can-
serum hormone levels was found (data not shown).
not differentiate vasculogenic and psychogenic eti-ologies. To assess the effectiveness objectively and
distinguish between organic and psychogenic erectiledysfunction, it is necessary to perform objective tests
In the present study, 10 (23.8%) patients were given
(e.g. the AVSS test, color duplex Doppler ultrasonogra-
50 mg of sildenafil, and 32 patients were given 25 mg.
Mean of the rigidity activity unit before and after administration of sildenafil
Mean of the tumescence activity unit before and after administration of sildenafil
Evaluation of sildenafil using audio-visual sexual stimulation
Because the AVSS test can detect an erectile response
In contrast, in the latter four patients who were con-
better than a vasoactive agent injection test, AVSS is
tent with sildenafil, the pretreatment average rigidity
thought to be one of the best evaluation methods.5 It has
was nearly zero. After treatment, however, the average
also been reported that the rigidity measured with the
rigidity rose to 40%. These patients may have been
RigiScan-Plus is correlated with the intracavernous
satisfied with this increase, or alternatively, they might
pressure.6 These facts suggest that the AVSS test is use-
achieve full erection at home in spite of poor erection
ful to determine the vascular cause of erectile dysfunc-
tion, which can be treated with sildenafil.
These results suggest that there are some patients
However, there are several problems associated with
whose results differ between the questionnaire method
the AVSS test: (i) If patients are repeatedly exposed to
and the more objective evaluation. Therefore, we con-
the sexual stimulation, the AVSS test might result in a
sider that a combination assessment with the IIEF-5 and
false negative response;7 (ii) several factors, such as
AVSS is more useful than the questionnaire method
exposure to the same erotic video, lack of interest in
alone, particularly when correct evaluation of the effec-
erotic movies, anxiety associated with their general
health, age, unfamiliar surroundings or connection to
In conclusion, our small clinical study suggests that
the measuring equipment might generate false negative
the AVSS test is one of the best available methods for
responses; and (iii) although sildenafil might provide the
best effect on erections at home, it is not certain whetheran accurate evaluation can we obtained using an in-office test.8
Reportedly, the maximum rigidity of the penis is a
predictor of the possibility of vaginal penetration, and
Rosen RC, Riley A, Wagner G, Osterloh IH, Kirkpatrick
its positive predictive value is 70% or higher.9 In the
J, Mishra A. The international index of erectile function
present study, the number of patients whose maximum
(IIEF): a multidimensional scale for assessment of erec-
penile rigidity was >70% was 22, which accounted for
tile dysfunction. Urology
the same proportion as in the questionnaire test. It has
National Institute of Health (NIH). Consensus develop-
ment panel on impotence: impotence. JAMA
also been reported that the average rigidity of the penis
can be used as a predictor of the possibility of erectile
Lue TF. Impotence: a patient’s goal-directed approach
maintenance and its positive predictive value is more
to treatment. World J. Urol.
than 40%.9 In the present study, there were 21 (50.0%)
Rosen RC, Cappelleri JC, Smith MD, Lipsky J, Pena
patients whose average penile rigidity was >40%. These
BM. Development and evaluation of an abridged, 5-itemversion of the international index of erectile function
results suggest that the AVSS test is as useful as the
(IIEF-5) as a diagnostic tool for erectile dysfunction. Int.
IIEF-5 in evaluating the effectiveness of sildenafil.
J. Impot. Res.
In four of the 42 patients for whom the treatment was
Katlowitz NM, Albano GJT, Morales P, Golimbu M.
considered effective by the AVSS test (average rigidity
Potentiation of drug-induced erection with audiovisual
>40%), it was considered ineffective using the IIEF-5.
sexual stimulation. Urology
Ku JH, Song YS, Kim ME, Lee NK, Park YH. Is there
In contrast, for four patients with under 40% average
a role of radial rigidity in the evaluation of erectile
rigidity, the IIEF-5 indicated that treatment was
dysfunction? Int. J. Impot. Res.
Kim SC, Bang JH, Hyun JS, Seo KK. Changes in erec-
In the former four cases, the pretreatment average
tile response to repeated audiovisual sexual stimulation.
rigidity had already reached more than 40%. After treat-
Pescatori ES, Silingardi V, Galeazzi GM, Rigatelli M,
ment, the average rigidity had increased up to only 70%.
Ranzi A, Artibani W. Audiovisual sexual stimulation by
For these patients, the tumescence, RAU and TAU after
virtual glasses is effective in including complete cav-
treatment exceeded the mean levels. Based on these
ernosal smooth muscle relaxation: a pharmacoca-
results, therefore, treatment was assessed as effective.
vernosometric study. Int. J. Impot. Res.
However, the patients might not have been satisfied with
Soh J, Naya Y, Kawauchi A, Fujito A, Fujiwara T, Miki
the relatively small increase in rigidity, from 40% to
T. [The examination using audio-visual sexual stimula-
70%, which is why the IIEF-5 tests showed ineffective
tion (AVSS) test for the effectiveness of sildenafil cit-
results of the sildenafil treatment.
rate.] Jpn J. Impot. Res.
: 31–6. (In Japanese.)
Effect of caffeine on metabolism, exercise endurance,and catecholamine responses after withdrawalM. H. VAN SOEREN1 AND T. E. GRAHAM21 School of Nursing, Faculty of Health Sciences, University of Western Ontario, London,Ontario N6A 5C1; and 2 Human Biology and Nutritional Sciences, University of Guelph,Guelph, Ontario, Canada N1G 2W1 Van Soeren, M. H., and T. E. Graham. Effect of caffeine a
SAFETY DATA SHEET ________________________________________________________________ Kiwicare Corporation Limited 225 Maces Road P.O Box 15050 Bromley Christchurch New Zealand Phone: +64 3 389 0778 Fax: +64 3 389 0669 EmWeb 1. IDENTIFICATION PRODUCT NAME: ________________________________________________________________ 2. HAZARDOUS IDENTIFICATION DANGEROUS GOODS CL