to end of treatment, when about 50% of patients
reported successful intercourse with demand-dose
therapy. Importantly, all the results were statistically
comparable between the two groups. Some impor-
tant caveats related to this study include a 30%
dropout rate of intrauretheral alprostadil supposi-
tory patients due to discomfort associated with the
treatment. Additionally, medication was provided to
each patient and compliance in a non-research
setting may be impacted substantially by the cost
of therapy. Finally, the absence of a control group
precludes definitive comparison of either therapy to
placebo or control.
Given the recognition that PGE1 is deficient after
RP-induced injury to the penile tissues, the afore-
mentioned investigators have utilized alprostadil
replacement therapy through injection or intraur-
etheral suppository supplementation. The study by
McCullough suggests some degree of equivalence
with PDE-5 inhibitor therapy.
Our protocol leverages this reported relationship
with PDE-5 inhibitors to diversify therapy for post-
RP patients. As with PDE-5 inhibitors, intrauretheral
alprostadil is a cornerstone of the EP program, and a
similar rationale toward the timing of initiation is
applied. While this therapy may be too expensive
mechanism of action to PDE-5 inhibitors and is thus
a critical component of the program.
Vacuum erection device
The vacuum erection device (VED) functions by
creating a negative pressure gradient around the
penis, drawing blood into the corporal bodies and
producing an erection. The suction produces the
functional benefit of the VED and a patient can place
a constriction ring at the base of the penis to siphon
off venous return enabling sexual performance.
While VED use is an established means of treating
ED in the general population, its use in post-RP
patients is less well established.
The absolute value of a VED after RP was
examined by Raina
et al
in a relatively large trial
comparing VED usage to no intervention in 109
post-RP patients. After 9 months, IIEF-5 (SHIM)
scores for patients in the VED group more than
tripled (4.8–16.0). Additionally, 32% of patients in
the VED group reported return of spontaneous
erectile function with more than half of these men
(52%) reporting erections sufficient for penetration.
These data compare with a 37% recovery rate for
non-VED patients, although only a small fraction of
these patients had sufficient rigid erection for
intercourse (29%). And, while IIEF-5 score changes
are not available because baseline data are not
reported, post-study scores are reported as 11.2.
The study also assessed satisfaction with penile
length in both groups, reporting an incomparable
65% satisfaction in the VED group (23% reported
absolute length decreases) versus a 63% prevalence
of patients reporting decrease in length in the non-
VED group. There are several important flaws with
the study related to inclusion criteria and the ability
to compare reported results. First, the study com-
bined patients with NS and non-NS RP. It is
inconceivable that the aggregate numbers can pro-
vide prognostic value or be objectively meaningful
since these patients had a poor prognosis to begin
with. Additionally, there was an 18% dropout rate
in the VED group, suggesting a selection bias in the
reported results. Finally, the authors report satisfac-
tion with length parameters in VED patients but
seemingly compare this with the observation to the
rate of absolute length declines in non-VED patients;
satisfaction of this latter cohort is neglected.
et al
conducted a randomized study of
scheduled daily VED use versus on-demand usage
for the first 6 months after RP. A subsequent
crossover for the latter group was then implemen-
ted, so the latter 6 months of the study consisted of
all patients using the device twice daily in back-to-
back 5-min increments. The study suggested that
use of VED substantially improved IIEF scores and
stretched penile length. Additionally, after the first 6
months of the study (when all patients were merged
into the scheduled VED use protocol), the differ-
ences between the two groups diminshed substan-
tially. The authors note that their study suggests
early implementation of VED therapy after RP as it
improves sexual function and stretched penile
length. However, there is no physiologic rationale
for the findings of this study, particularly given
that VED-induced penile blood flow is said to have
the same oxygen tension as venous blood.
authors suggest that the mechanism may somehow
be related to amelioration of penile apoptosis, but
penile hemodynamics with VED would not support
this conclusion. Additionally, patients in both
groups were noted to have IIEF declines from about
20 to 10 from pre-RP IIEF scores to initiation of
the study. Scores were then maintained in VED
patients, but declined in the control group. It is
unclear why scores would decline in this latter
group at 1 month when previously described data
clearly present an upward trend in IIEF scores at
this time point. With respect to penile length
preservation, the mechanism of the VED is unclear.
This result alone would not justify use in an EP
program but suggests a complementary role for VED
therapy rather than utilizing it as monotherapy for
post-RP patients.
Perhaps, the most relevant published experience
with the VED was conducted by Raina
et al
. who
looked at the incremental value of including a PDE-5
inhibitor in combination with VED usage. As a
subgroup analysis of their previously described
study, the group examined VED usage alone com-
pared with VED
sildenafil (100 mg, 1–2 h before
sexual intercourse) with respect to functional ability
Review and treatment protocol: erectile preservation for RP patients
DJ Moskovic
et al
International Journal of Impotence Research