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

for

some

patients,

offers

complementary

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.

32,33

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.

Kohler

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.

The

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

185

International Journal of Impotence Research