Urethral stump carrier for radical retropubic prostatectomy

A smooth blunt tip tubular structure in a form of a sound or a catheter and a pressure producing and regulating system. The sound or the catheter has a smooth blunt end on one end and a non blunted end on the opposite end. There is a lumen extending from one end to the opposite end. There is a furrow running circumferentially around the blunt end of the sound or the catheter. The furrow lies on the side wall within two centimer from the blunt end tip of the sound or the catheter. There are multiple openings on the floor of the furrow. The openings within the furrow communicate with the lumen of the sound or the catheter. The pressure producing end regulating system is in fluid communication with the lumen. The side walls of the furrow elevate above the surface of the sound or the catheter forming ridges. There are six grooves equally distanced from each other between the furrow and the tip of the sound or the catheter. With the entire system in operative condition, the tip of the sound or the catheter is able to carry by suction, the transected segment of membranous urethra to the pelvis for it to be anastomosed to the bladder neck at the time of radical retropubic prostatectomy.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates an improved device with a different working mechanism 
and principle from the conventional instrument to carrying the retracted 
distal segment of membranous urethra, thereafter called the urethral 
stump, from the urogenital diaphragram of the pelvis into the pelvis for 
easy anastomosis of said urethral end to the bladder neck in a procedure 
called Radical Retropubic Prostatectomy. 
2. Description of the Prior Art 
In an operation called "Radical Retropubic Prostatectomy" for the treatment 
of a patient with a localized cancer of the prostate, the membranous 
urethra is identified distal to the apex or distal tip of the prostate. 
The membranous urethra is transected and the prostate is removed. The 
distal segment of the transected membranous urethra, thereafter called the 
Membranous Urethral Stump, is sutured to the bladder neck with absorbable 
sutures. It happens that in most instances, the urethral stump retracts 
and recedes within the muscle of the pelvic floor, the urogenital 
diaphragram, and cannot be seen again. Anastomosis of the urethral stump 
to the bladder neck, therefore became extremely difficult and sometimes 
impossible. Prior inventions consist of using urethral sounds or catheters 
of larger diameter than the urethra to push or carry the urethral stump 
into the pelvis for anastomosis. The principle of the prior art rely on 
the friction formed between the sound and the urethra; since the urethra 
is an elastic tube, it expands as the instrument is inserted within its 
lumen. The urethral stump tends to slide back the end of the instrument, 
it then retracts back into the muscle of urogenital diaphragram. The 
anastomosis between urethra and the bladder neck becomes impossible. 
SUMMARY OF THE INVENTION 
The invention is an improved urethral sound or a catheter connected to a 
fine scale positive and negative pressure generating system. The sound or 
the catheter can be rigid or flexible, it has an external diameter the 
same as the diameter of the normal male urethra usually between twenty to 
twentyfour French in size, there is a smooth central lumen extending from 
the blunt tip of the sound or the catheter to the opposite non blunt end 
of the stem of the sound or the catheter. The non blunt end of the stem of 
the sound or the catheter is connected to a fine scale pressure generating 
system which is able to produce a positive and a negative pressure and is 
able to maintain it in a desirable pressure range automatically. The blunt 
end of the sound is slightly curved if it is a rigid instrument. It can be 
straight or slightly curved if it is a flexible catheter. The blunt end of 
the sound or the catheter is smooth and atraumatic. There is a narrow 
furrow measuring one centimeter in width and less than five milimeters in 
depth engraved circumferentially on the outer surface of the blunt end 
segment of the sound or the catheter within one inch from the tip of the 
blunt end of the sound or the catheter. The valley of the furrow is deepen 
into the wall of the catheter or the sound. There are multiple openings, 
whether the openings are small or large, regardless of the numbers of the 
openings, located at the valley of the furrow. The openings at the valley 
of the furrow communicate with the lumen of the sound or the catheter. The 
edges where the side walls of the furrow became in contact with the 
surface of the sound are elevated. There are two elevated lines or ridges 
on the surface of the sound or the catheter, one ridge line on each side 
of the furrow of the sound or the catheter, within one inch proximal to 
the tip of the sound or the catheter. The ridges lines run 
circumferentially around the sound or the catheter atop either side walls 
of the furrow of the sound or the catheter. The tip of the sound or the 
catheter is blunt ended. There is a single opening less than three mm in 
size at exactly the tip of the blunt end of the sound or the catheter; the 
opening at the tip of the blunt end of the sound or the catheter 
communicates with the central lumen of the catheter. There are six shallow 
grooves on the lateral surface of the blunt end segment of the catheter or 
the sound. The grooves locate between the furrow and the tip of the blunt 
end of the sound or the catheter. The grooves are engraved into the wall 
of the sound. They are evenly distanced from each other and parallel to 
the axis of the catheter. After the prostate was removed during the 
procedure of radical retropubic prostatectomy, the blunt end of the sound 
or the catheter is inserted into the urethra through the male urethral 
meatus. The tip of the sound or the catheter is just barely visible in the 
membranous urethral stump through the pelvis. A desirable negative 
pressure is created and maintained in the pressure producing system. The 
negative pressure is transmitted to the lumen of the sound or the 
catheter. The membranous urethral wall is then aspirated into the furrow 
of the sound or the catheter. The elevated ridges besides the furrow 
resist the urethral tissue from sliding back toward the stem of the sound 
or the catheter as the tip of the sound or the catheter is advanced toward 
the pelvic cavity. The small hole at the very end of the blunt end of the 
sound or the catheter works as a sump to prevent the tissue from damaging 
or developing a hematoma in the area of the urethra near the furrow as the 
result of the negative pressure aspiration. The urethral stump which was 
carried from the urogenital diaphragram to the pelvis is therefore ready 
for anastomosis. After the anastomosis of the the membranous urethra to 
the bladder neck is completed, the aspirated urethral wall in the furrow 
of the sound or the catheter is then ejected by a positive pressure 
generated in the pressure generating system. The urethral sound or the 
catheter can therefore be removed. 
The present invention utilizes a different principle of the physics by 
creating a negative pressure in the lumen of the sound or the catheter to 
receive and carry the membranous urethral stump to the pelvis during the 
surgery.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 is external view of the entire system showing the urethral stump 
carrier "Q" and the pressure generating and regulating system "P" 
connected together and in operative condition. The urethral stump carrier 
in the form of the sound or the catheter "Q" is connected to the pressure 
producing and regulating system "P" with a non collapsable flexible tube 
"O". 
FIG. 2 is a external side view of the urethral stump carrier "Q". The 
distal end of the carrier in the form of the sound or the catheter "B" is 
smooth and blunted. It tapers slightly toward the tip. The proximal end of 
the sound or the catheter "A" is open ended, it slightly tapers to a 
segment of corrugated connecting part "N" where the flexible pressure 
resistant non collapsable tube "O" from the pressure generating and 
regulating system (FIG. 1) is connected. The external diameter "M" of the 
urethral stump carrier should be comparable to the usual male urethral 
diameter, it usually ranges from twenty to twentyfour French or 6.7 to 8 
millimeter in diameter, whereas the length of the sound or the catheter (X 
plus Y plus W) should be longer than the usual adult male urethral length. 
The distal end of the sound or the catheter B can be straight or slightly 
curved. Within two centimeters from the tip of the catheter "B", a deep 
furrow or a groove "C" lies circumferentially in the wall of the sound or 
the catheter. There are multiple openings "E's" located at the valley of 
the furrow. The openings "E's" on the valley of the furrow "C" are equally 
distanced; the openings penetrate through the entire thickness of the wall 
of the sound or the catheter. The openings communicate with the central 
lumen of the catheter "G" (as shown in FIG. 3 and FIG. 4). As the side 
walls of the furrow rise to intersect with the surface of the sound or the 
catheter, they form two elevated ridges, "F's" (as shown on FIGS. 1 
through 6), proximal and distal to the furrow. Said elevated ridges run 
circumferentially around the sound or the catheter and parallel to the 
furrow of the sound or the catheter. There are six ellipse shape grooves 
"D's", engraved in the side wall of the sound or the catheter distal to 
the furrow "C", the grooves "D's" are equally distanced from each other 
and are not in communication with the central lumen of the sound or the 
catheter "G" (as shown in FIG. 3 and FIG. 5). The grooves designate the 
sites of the needle placement during the process of anastomosis. At the 
most distal end of the sound or the catheter a small opening "H" measuring 
less than three mm in diameter is created, the opening "H" communicates 
with the lumen of the sound or the catheter "G" (as shown in FIG. 3). In 
the case of a flexible catheter, a loop attachment "K" is constructed 
external to the opening at the tip of the catheter for the placement of a 
suture for the purpose of traction of the catheter during the operation 
(as shown in FIG. 6). When the urethral sound or catheter carrier "Q" is 
connected to a pressure generating and regulating system "P" with a 
pressure resistant tube "O" (as shown in FIG. 1), the system is in an 
operative condition. The pressure producing system in this invention is 
able to produce positive and negative pressure and to maintain it at the 
desirable pressure range. For manufacture and cleaning simplicity, the 
urethral stump sound or catheter can be divided into three parts, W, X and 
Y. They are connected together in one piece at S and T where male and 
female screw threads are located as is shown in FIG. 3. The sound or the 
catheter can also be made in one piece. 
FIG. 3 illustrates the longitudinal section view of the urethral stump 
carrier "Q". Each letter on the drawing corresponds to the letter shown in 
other Figures in each embodiment. 
FIG. 4 is a cross section view of the urethral stump carrier at the valley 
of the furrow, on cross section plane "J" (as shown in FIG. 2). The figure 
illustrates the multiple openings "E's" communicate with the central lumen 
"G" of the sound or the catheter. The openings "E's" are equally 
distanced. 
FIG. 5 is a cross section view of the urethral stump carrier at the tip of 
the sound or the catheter "B" distal to the furrow "C" on plaine I (as 
shown in FIG. 2). The grooves D's are engraved in the wall of the sound or 
the catheter. The grooves do not communicate with the lumen of the sound 
or the catheter "G". 
FIG. 6 illustrates one of the embodiments of present invention. A straight 
flexible catheter is made in one piece. The catheter has a loop "K" at the 
end of the tip the catheter. The loop is made for placement of a suture 
for the traction of the catheter. 
FIG. 7 is a magnification of the external view of the head of the sound 
showing another embodiment of the present invention with the floor of the 
furrow full of multiple mesh like opening "Z's". There are multiple 
bridges "R's" between the meshes. The purpose of forming bridges "R's" 
between the meshes "Z's" is to maintain a solid attachment of the head of 
the sound B to the shaft of the sound. 
FIG. 8 is another embodiment of the sound showing the furrow of the sound 
is more distally located and overlapped with the suture grooves. In the 
drawing, there are mesh-like openings interposing with the suture grooves. 
The suture grooves are also the bridges "R's" in this drawing. Although 
detailed embodiments of the invention and their variants are illustrated 
in the drawings and previously described in detail, this invention 
contemplates any configuration, dimention, design and relationships of the 
components except otherwise specified which will function in a similar 
manner and which will provide the equivalent result.