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Benign Prostatic Hyperplasia
hydrostatic pressure in the testicular venous drainage system is volume homogeneously in all dimensions; however, it leaves the
achieved, back-pressure and back-flow to the prostate are gland intact while reducing the pressure exerted on the urethra.
eliminated. Blood from both drainage systems, meeting at the VV,
now jointly flows towards the II, the CI and, ultimately, the IVC. Then Conclusions
the effects of back-pressure and back-flow do not exist anymore. BPH develops due to an impairment of the testicular venous drainage
The intra-prostatic pressure returns to normal and the volume of system in the erect posture of the human. Based on a fluid mechanics
the gland decreases rapidly, at least partially, within weeks. analysis of an impaired testicular venous drainage system and the
Androgen now arrives only via the prostatic artery and the results of the developed treatment, the following statements can be
concentration of FT arriving at the prostate is physiological: <1% of made. BPH is caused by increased hydrostatic pressure in the prostate
the level before treatment. The proliferation/apoptosis ratio
2
returns drainage system, while BPH is caused by an excessively high
to normal and on the one hand, prostatic cells are no longer under concentration of FT, both arriving at the prostate by pathological back-
the influence of excessive pathological proliferative stimuli, and on pressure and back-flow from the testicular to the prostate drainage
the other hand, there is a drastic reduction in the maintenance systems. Eliminating the pathological hydrostatic pressure in the
capacity of (hyperplasic) prostate cells as the supplied androgen testicular venous drainage system by occlusion of the impaired ISVs,
level returns to <1% compared with the level before treatment. The including all the associated venous bypasses and retroperitoneal
prostate returns gradually towards the normal ‘steady state’, with collaterals by super-selective transvenous sclerotherapy or by
the degree of improvement also depending on the gland’s elastic microsurgery eliminates the venous back-pressure and back-flow of
properties, which also depends on the age of the patient and the blood to the prostate. This reduces its exposure to elevated FT. This
duration of the disease. initially reduces benign prostate hypertrophy and, subsequently (at least
partially), reverses BPH. We recommend that patients with BPH be
Hydraulics, Benign Prostate Hyperplasia and examined for bilateral varicocele and be treated according to the
Lower Urinary Tract Symptoms suggested treatment that, at least partially, reverses BPH. ■
An enlarged prostate has two adverse mechanical effects on the
urinary system: it reduces the bladder volume reservoir, leading to
frequency of urination, and, by exerting pressure on the urethra, it
Yigal Gat is Head of Andrology–Interventional Radiology
at the Maayanei Hayeshua Medical Centre and a
narrows the urethral diameter, causing weak stream and limiting
Research Consultant at the Weizmann Institute of
bladder emptying, as complete emptying in a narrowing urethra
Science in Rehovot in Israel. He has worked as a senior
requires increasing intra-vesicular pressure.
andrologist at the Rabin Medical Centrer since 1985. His
research on fluid mechanics of venous drainage in the
male reproductive system led him to develop the Gat-
According to the principle in fluid mechanics developed by
Goren technique, which improves sperm production and
Hagen-Poiseuille
15
in 1838 (Q
testosterone production and reverses benign prostate
2
/Q
1
= [D
2
/D
1
]),
4
which describes the rate
hyperplasia. Professor Gat received his PhD from Ghent
of flow in relation to the changing diameter of the vessels (Q is rate of
University Hospital and his MD from Tel-Aviv University.
urine flow, Q
1
= normal conditions, Q
2
= BPH; D is the uretheral
diameter, D
Michael Gornish is an Interventional Radiologist
1
= in normal conditions, D
2
= in BP), it can be calculated
by approximation that when the urethral diameter is reduced by only
specialising in the male pelvis at the Maynei Hayeshua
Medical Center in Bnei Brak in Israel. He was a Senior
30% due to the pressure exerted by the enlarged prostate gland, the
Radiologist and the Neuroradiology Section Chief at Rabin
urine flow is drastically reduced to about 24% of its normal stream
Medical Centre, where he gained experience in the
capacity,
15
i.e. if D
venous anatomy of the male pelvis under Professor Mark
2
= 0.7 D
1
, Q
2
= 0.24 Q
1
in the same manner; if the
Kunnen at the University of Ghent in Belgium. Dr Gornish
urethral diameter decreases to 50%, the urine flow will deteriorate to
received his BA cum laude in biology from Harvard
about 7% of the normal flow. The above-proposed treatment reduces
University and his MD from Temple University.
intra-prostatic pressure, resulting in a general decrease in prostate
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14 EUROPEAN UROLOGICAL REVIEW