A live 3D ultrasound system with colour Doppler to study the effect of
sildenafil on erectile performance in patients with chronic and serious diseases
presenting with erectile dysfunction
R. Chatterjee (1), J. Deng (2), D. Pellerin (2), A. Todd-Pokropek (3),
C.H. Rodeck (1), W.R. Lees (4)
Departments of Obstetrics and Gynaecology, UCL (1); Department of
Cardiology, The Heart Hospital, UCL (2); Departments of Medical Physics, UCL
(3); Departments of Radiology, UCL, London, UK (4)
Introduction: Patients with chronic and serious diseases (CSD), have a
higher incidence of erectile dysfunction (ED) affecting 60–80% of survivors.
As the pathophysiology is poorly understood, CSD men with ED often remain
undiagnosed and untreated with significant affection of their quality of life.
Objective: The aim of this study was to determine functional anatomy
of penis and cavernosal vascular haemadynamics in CSD suffering from erectile
dysfunction (ED) before and after sildenafil therapy.
Patients and methods: Erectile performance of 5 CSD patients aged 26–55
(median 51) years was assessed before and after 50– 100 mg of sildenafil. Two
healthy age matched volunteers acted as controls. A Live 3D system by Philips
Ultrasound was used for 4D anatomical data acquisition at a rate of 20 –24
volumes per second. ECG gating was used for 4D colour-Doppler blood flow data
collection. To enable the 4D scans to be carried out in a physiological
condition, a water-filled vagina was devised to allow patients to insert the
penis in and to perform artificial intercourse in it. Off-line analysis was
performed on TomTecs 4D CardioView.
Results: At base line, the size of the penis was small and the
cavernosal blood flow was virtually undetectable in controls as well as the
patients. Within 45 mins of oral Sildenafil, all patients had successful
erection of grade II (partial) to grade III (with full rigidity) which was
comparable to the erectile performance of the controls without sildenafil.
Erection was associated with an increase in penile size, volume and length in
both patients and controls. In addition, there was a marked increase in
cavernosal blood flow with high velocity during erection. However, despite
having successful erection, the patients had cavernosal arteriogenic
insufficiency compared to the controls. Following detumescence, there was
evidence of urethral dilation followed by return of structural and haemodynamic
changes to base line values.
Conclusions: Our data suggest that 4D images of the erection and
subsequent changes in vasculature can be observed in real time by using live 3D
ultrasonography and Colour Doppler. This method also offers a potential means of
volumetric quantitation of the geometric change and increment of the whole
penis, individual corpora cavernosa penis and urethra and penile haemodynamics.
We propose that this novel technique can be used as a diagnostic tool to
understand the pathophysiology of ED.