Cylindrical anal retractor

A cylindrical anal retractor for examining the inside of an anus of a living body including an inserting valve portion inside of which a substantially circular-shaped opening is formed, a handle which serves to dilate the opening by gripping it, and an auxiliary appliance for making the insertion of the inserting valve portion into the anus smooth; the trivalve inserting portion has three plate-like members, which are curved inside, and two of the members are connected to the handle so as to be rotatable about axes extended in an inserting direction of the inserting valve portion. In the anal retractor according to the present invention, therefore, the pain which is given to the patient when the anal retractor is inserted into his or her anus is remarkably reduced.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a cylindrical anal retractor, more 
particularly, to a trivalve cylindrical anal retractor which is used in an 
operation or as assistance in an operation, upon the inside of an anus or 
rectum of a living body. 
2. Prior Art 
As is well known, an anal retractor is used to examine the inside of an 
anus and/or rectum of a living body by inserting the distal end portion 
thereof into the anus and/or rectum. The anal retractor is also used as an 
auxiliary appliance for inserting medical appliances such as forceps and 
fiber scopes into the anus or rectum in order to examine, wash, or treat 
the inside wall thereof. Recently, such an anal retractor is frequently 
used to perform an operation with the inside wall thereof. Such operations 
are advantageous to patients because the operation can be performed 
without a laparotomy. 
On the other hand, an inosculating device is often used to inosculate 
damaged canals. Such a device is inserted into the damaged canals via the 
anus in accordance with a portion to be inosculated, then operated to 
inosculate them with each other. When inserting the inosculating device 
into the anus, the operator hitherto dilated the anus with his or her 
fingers. However, it is difficult to insert the inosculating device into 
the anus without great pain to the patients and also is difficult to get a 
good surgical field with the previous device. In order to make the 
insertion of the inosculating device easy and safe and to get a better 
surgical field, the anal retractor is recently used as an auxiliary 
appliance for inserting the inosculating device into a cavity via an anus. 
FIG. 1(A) is a perspective view showing the construction of a conventional 
cylindrical examination anal retractor. The conventional anal retractor 
comprises a cylindrical anal retractor body 1 and an auxiliary appliance 
2, which allows the anal retractor to be inserted into the anus smoothly; 
the cylindrical anal retractor body 1 consists of a cylindrical inserting 
portion 10 and a handle 11. On a distal end portion of the auxiliary 
appliance 2, a bullet shaped insertion head 20 is provided, and on a 
proximal end portion thereof are arranged a finger hook ring 21 and a 
holder 22. 
The conventional cylindrical examination anal retractor is used under the 
condition illustrated in FIG. 1(B). That is to say, the auxiliary 
appliance 2 is inserted into the cylindrical inserting portion 10 of the 
anal retractor body 1 and fixed therein with the aid of the holder 22. 
Since the cylinder 10 has a tapered shape, whose posterior side is larger 
than the anterior side, the auxiliary appliance 2 can be easily secured in 
the inserting portion 10 with the aid of the plate-like holder 22. After 
the auxiliary appliance 2 is mounted and secured in the inserting portion 
10 in this manner, the inserting portion 10 of the anal retractor is 
inserted into the anus of a patient in a direction as shown by the arrow 
A. After inserting portion 10 is inserted a predetermined depth into the 
anus; an operator pulls the auxiliary appliance 2 from the anal retractor 
in a counter direction as shown by the arrow B to remove it, leaving the 
cylindrical anal retractor body in the anus. The operator can easily 
remove the appliance 2 by hooking his or her finger on the ring 21. The 
anal retractor is inserted into the anus of a patient in this manner. The 
inside of the anus or rectum of the patient is exposed via an opening of 
the anal retractor and the operator can examine the exposed inside using a 
naked eye; and then the operator can provide the suitable treatment such 
as a washing on the affected part of the anus or rectum or perform an 
operation. 
However, as clear from FIG. 1, such a conventional anal retractor has only 
one opening at the distal end of the cylindrical inserting portion to 
expose the inside of the cavity. Since the entire wall of the anus or 
rectum cannot be exposed via this opening, the operator cannot fully 
examine the inside of the anal wall and it is difficult to perform an 
operation with such a small field of view. Further, in order to examine 
the inside fully and give a suitable treatment on the affected part, the 
operator has to move the anal retractor in the cavity; but, such a 
movement of the anal retractor gives great pain to the patient. 
Furthermore, when the anal retractor is inserted into the cavity, the 
auxiliary appliance 2 should be inserted into the cylindrical anal 
retractor body 10, which is formed as a united body, and the bullet-shaped 
top portion 20 provided at the distal end of the auxiliary appliance 2 is 
protruded from the opening of the cylindrical body 10. Therefore, a step 3 
is formed at the connected portion of the opening of the cylindrical body 
10 and the outer surface of the top portion 20 of the auxiliary appliance 
2, as shown in FIG. 1(C). This step gives greater pain to the patient when 
the anal retractor is inserted into his or her anus. 
FIG. 2 is a schematic view showing the construction of a conventional 
trivalve anal retractor, which has been developed in order to obtain a 
wider field of view and reduce the pain to the patient when the anal 
retractor is inserted into his or her anus or the anal retractor is moved 
inside of his or her cavity. In FIG. 2(A), which is a plan view of the 
anal retractor, the numerical reference 41 represents a handle, 42 a 
slidable stay, 43 a gauge screw, 44 a spring and the numerical reference 
45 represents an inserting valve portion. FIGS. 2(B) and 2(C) are side 
views of the inserting valve portion 45, which is arranged to be able to 
open. FIG. 2(B) shows a condition where the valves are closed together and 
FIG. 2(C) depicts a condition where the valves are separated from each 
other to obtain an opening inside of the inserting valve portion 45. The 
numerical references 45a to 45c, respectively, represent valves, 46 an 
opening formed there inside and 47 shows a round inside wall of each 
valve. As shown in FIG. 2(B), the distal end portion of the valves 45 is 
arranged to form a bullet shape when the valves are closed together, so 
that the anal retractor can be inserted into the anus without giving much 
pain to the patient. 
In the thus constructed trivalve anal retractor, when no force is given to 
the handle 41, the valves 45a to 45c are closed together by the energy of 
the spring 44; but when gripping the handle 41, both the upper left and 
the upper right valves 45a and 45b are opened in left and right 
directions. At the same time, the slidable stay 42 is moved to a rear 
direction; and in accordance to the movement of the slidable stay 42, 
another valve 45c is moved to a lower direction shown in FIG. 2(B) to form 
an opening 46 inside of the valve portion 45. 
The trivalve examination anal retractor is inserted into the anus until it 
reaches a predetermined depth under the condition that the valves 45 are 
closed together; and then the valves 45 are opened by gripping the handle 
41 to form an opening 46 inside of the valves 45 as shown in FIG. 4(C). 
The operator visually examines the inside of the anus via the opening 46 
and gives a suitable treatment, such as washing, to the affected part of 
the patient. In the anal retractor shown in FIG. 2, it is possible to 
obtain a wider field of view in comparison with the retractor shown in 
FIG. 1. However, the field of view thereof is not enough to fully examine 
the inside of the anus or perform an operation. 
In addition to the above, in the conventional trivalve anal retractor, the 
valve portion 45 is connected to the handle 41 so as to form a right 
angle, as shown in FIG. 2(B). Therefore, the anal retractor has a drawback 
that it is difficult for the operator to control the anal retractor easily 
after the anal retractor is inserted into the anus. 
The anal retractor has another drawback namely that an ideal 
circular-shaped opening cannot be obtained at the distal end thereof. In 
the trivalve anal retractor, it is desired that each valve opens outside 
in an even manner. However, in the conventional anal retractor, the upper 
left and the upper right side valves 45a and 45b are fixed to the ends of 
the handle 41, respectively; therefore, these vales are opened to the 
perspective lower directions, respectively, as shown by the arrows c and d 
in FIG. 4(B). Furthermore, the valves are designed to form a bullet shaped 
top when the valves are closed together, in order to make the insertion 
thereof into the anus easy, taking the pain given to the patient into 
consideration. Therefore, each of the valve has a round surface, which is 
curved inside of the inserting portion. Thus, when the valves 45 are 
opened after the anal retractor is inserted into the anus, the round 
portions 47 of the valves protrude inside the opening 46, so that the 
actual circular-shaped opening cannot be obtained in the conventional 
trivalve anal retractor. It should be noted that the round shaped valves 
prevent a full examination of the inside of anus and also hinders an 
operation. 
FIG. 3 shows the construction of a conventional inosculating device for 
inosculating damaged alimentary canals. In FIG. 3(A), the numerical 
reference 4 represents an inoculator, 50 an inserting portion thereof, 51 
a handle, 52 a first inosculating section and 53 represents a second 
inosculating section. FIG. 3(B) is a cross-sectional view of the first 
inosculating section 52. As shown in FIG. 3(B), on the outer circumference 
of the first inosculating section 52, a plurality of clips 54 are 
arranged; and in an inner circumference thereof, there is embedded a 
cutter for cutting out the damaged alimentary canals. As stated in the 
above, such an inosculating device is inserted into the damaged alimentary 
canals via the anus and used to inosculate them to each other as like a 
stapler. 
The inosculation is conducted in such a manner that the inserting portion 
50 is inserted into the damaged canals via the anus of the patient until 
the first inosculating section 52 disposed at a distal end of the 
inserting portion 50 is exposed from one of the separated (damaged) 
alimentary canals 56a; then the first inosculating section 52 is further 
pushed out until the first inosculating section 52 is covered with the 
other separated (damaged) alimentary canal 56b, as shown in FIG. 3(C). 
Then the handle 51 is gripped or closed to fit the first inosculating 
section 52 with the second inosculating section 53. By this gripping 
operation, the separated (damaged) alimentary canals 56a and 56b are 
inosculated to each other with the aid of the clips arranged in the outer 
circumference of the first inosculating portion 52. At the same time, the 
cutter 55 operates to cut out the damaged part of the canals. After the 
inosculation is finished, the inoculator 4 is taken off from the cavity 
via the anus, as shown in FIG. 4(E). 
Hitherto, when such inosculation was conducted, the inoculator 4 was 
inserted into the anus of the patient, directly. The operator open the 
anus of the patient with his or her fingers and therefore, sometimes the 
anus was hurt and caused the patient great pain. In addition to this, 
since an anus generally has a contractility, the inoculator 4 was inserted 
into the anus with great attention by the operator and with great force to 
push it into the anus, so it was difficult for the operator to insert the 
device into the cavity via the anus and use the device smoothly. 
The inosculation of the damaged alimentary canals was conducted in such a 
condition that the canals to be inosculated to each other were kept 
dilated by the inosculating device 4. Therefore, the distal end of the 
inserting portion 50 of the device was designed to be larger than the 
diameter of the canals to be inosculated. If the device having such large 
diameter of the inserting portion is directly inserted into the anus of 
the patient, not only the insertion is difficult but also the patient 
experiences great pain. 
Moreover, since great force is necessary to insert the device into the anus 
or remove it therefrom, it is required that the other operator keep the 
anus of the patient open with the aid of an anus opening appliance, during 
which the inosculating device is inserted into the anus or taken 
therefrom. Therefore, at least two operators are necessary to conduct the 
inosculation of the alimentary canals when the conventional device is 
used. 
SUMMARY OF THE INVENTION 
One purpose of the present invention is to provide a cylindrical anal 
retractor having a large field of view, which is easily used by an 
operator, and can be inserted into the patient's anus without great 
discomfort to the patient. In order to carry out the invention, the 
cylindrical anal retractor according to the present invention has a 
construction which allows the anal retractor to be smoothly inserted into 
the anus, and after the insertion the anus can be dilated enough to obtain 
a larger field of view without giving pain to the patient. The valves 
which form the inserting portion of the retractor have thin and curved 
plate-like shapes so that an excellent circular-shaped view field can be 
obtained when the valves open in the anus. Further, a part of the valve 
portion is arranged to be rotatable about axes extended in an inserting 
direction of the valve portion, so that no exceeding tension is given to 
the anus of the resulting patient and the pain is reduced when the valve 
portions are opened after the insertion. Furthermore, the inserting 
portion of the anal retractor is connected to the handle with an angle of 
90 degrees or more to improve the controllability of the anal retractor; 
and the outer surface of the inserting portion of the anal retractor is 
designed to be smooth by providing a step on an outer surface of the 
distal top portion of the auxiliary appliance of the anal retractor, so 
that the anal retractor can be inserted into the anus smoothly. 
The second purpose of the present invention is to provide an inosculating 
device having an anus dilator. By the inosculating device according to the 
present invention, the anus dilator is inserted into the anus first, and 
then the inoculator is inserted into the alimentary canal via the dilated 
anus using the dilator as a guide, and thereafter the anus dilator is 
removed. Therefore, it becomes easy to insert and remove the inosculating 
device into and from the canal via the anus and the pain to the patient 
during the inosculation of the alimentary canals is much reduced.

DETAILED EXPLANATION OF THE PREFERRED EMBODIMENTS 
The preferred embodiments of the cylindrical anal retractors according to 
the present invention are explained below. 
FIG. 4(A) is a plan view showing a construction of a trivalve examination 
cylindrical anal retractor according to one embodiment of the invention; 
and FIG. 4(B) is a perspective view depicting an inserting portion of said 
anal retractor in an enlarged scale. In FIG. 4, the numerical reference 
100 represents an anal retractor body, 101 a handle, 102 a slidable stay, 
103 a gauge screw, 104 a spring, 105 an inserting valve portion, and the 
numerical references 105a to 105c represent valves, respectively. The 
valves 105a and 105b are secured to an end portion of the handle 101 so as 
to be rotatable about axes extended in an inserting direction of the anal 
retractor 100. The numerical reference 106 represents pins for securing 
the valves 105a and 105b to the handle 101 in a rotatable manner. These 
pins serve as the rotating axes of these valves 105a and 05b. On the other 
hand, another valve 105c is fixed to an end portion of the slidable stay 
102. Therefore, when the operator grips the handle 101, these valves 105a, 
105b and 105c open outside, and are separated from each other, so that the 
valve portion 105 opens outside to form an opening inside thereof. As 
shown in FIG. 4(B), when the valve portion 105 opens outside, the valves 
105a and 105b are separated from each other, keeping their condition to be 
freely rotatable in directions shown by the arrows E and F. In this 
manner, the trivalve examination cylindrical anal retractor 100 according 
to the present invention is designed such that the valve portion 105 can 
be dilated and some parts of the cylindrical inserting portion (valve 
portion) 105 are rotatable with respect to the handle 101. Therefore, when 
the inserting valve portion 105 is inserted in the anus, no excessive 
tension it given against the inside wall of the anus. 
In the anal retractor according to the present invention, a cylindrical 
body is constituted of the valve portion 105: and each valve comprises a 
loosely curved plate-like member. Thus a circular opening is obtained at 
the distal portion of the inserting valve portion 105. That is to say, the 
operator can obtain a wide view field with the anal retractor. 
The anal retractor 100 is inserted into a cavity, such as an anus, with the 
aid of an auxiliary appliance 110 as like the conventional cylindrical 
examination anal retractor. FIG. 5(A) is a side view showing a condition 
when the auxiliary appliance 110 is inserted into the cylindrical 
body(inserting valve portion) 105 of the anal retractor 100. The inserting 
valve portion 105 of the anal retractor 100 is inserted into an anus of a 
patient under the condition shown in FIG. 5(A). According to the present 
invention, the inserting valve portion 105, which forms the cylindrical 
body, is fixed to the handle 101 so as to form an angle .alpha., which is 
90 degrees or more, between the valve portion 105 of the anal retractor 
and the handle 101. Therefore, the operator can easily handle the anal 
retractor when the anal retractor is inserted in or removed from the 
cavity via the anus. 
The auxiliary appliance 110 has the same construction as that of the 
conventional one shown in FIG. 1, with the exception of the construction 
of a distal top portion 112 thereof. It should be noted that the 
explanation for the parts than the distal top portion 112 is therefore 
omitted here. In the auxiliary appliance 110 used in the anal retractor 
according to the invention, around an outer surface of the bullet shaped 
distal top portion 112, is provided a step 111 as shown in FIG. 5(B). 
Therefore, when the auxiliary appliance 110 is mounted into the 
cylindrical body of the anal retractor 100, the step 111 is suitably 
coupled with the opening of the cylindrical body 105. Therefore, the 
connecting portion between the distal top portion 112 of the auxiliary 
appliance 110 and the opening of the cylindrical body 105 is smooth, so 
that it is easier to insert the anal retractor into an anus and pain 
reduces of the patient when the anal retractor is inserted. 
While the anal retractor, in which the auxiliary appliance 110 is mounted, 
is inserted into the anus to a predetermined depth the valves 105 are 
closed. Once of the desired depth, the operator grips the handle 101 a 
little to open the valves 105 in order to remove the auxiliary appliance 
110 from the cylindrical body of the anal retractor 100. Since the step 
111 is provided on the distal top portion 112 of the auxiliary appliance 
110, the appliance 110 cannot be removed therefrom without opening the 
valves 105. 
After taking off the auxiliary appliance 110 from the cylindrical body, the 
operator grips the handle 101 again to open the valves 105 much more to 
obtain a circular view field having a desired dimension at the distal end 
of the cylindrical body. In order to keep the dimension of the view field, 
the opening degree of the handle is fixed with the aid of the gauge screw 
103. It should be noted that other latch mechanisms may be used instead of 
the gauge screw 103. In the anal retractor according to the present 
invention, since the valves 105a, 105b and 105c are designed to be 
plate-like members which are curved inside, respectively, it is possible 
to obtain a circular and wide view field when the valves are open. 
Therefore, the operator can conduct a visual examination, and provide 
suitable treatment easily through the circular-shaped opening. Further, 
the circular and wide opening creates access in an operation on the anus 
or rectum. 
When the valves 105 are open, each of the valves 105a to 105c is strongly 
urged against the inside wall of the anus or rectum, and thus the patient 
gets pain. However, according to the present invention, since the upper 
side valves 105a and 105b are arranged to be rotatable about axes extended 
in an inserting direction of the anal retractor, the tension against the 
anus wall is remarkably reduced. 
FIG. 6 shows another embodiment of the invention and including an 
inosculating device for inosculating alimentary canals. The inosculating 
device comprises an inoculator 4 and an anus dilator 100 which is suitably 
used as a guide for the inoculator 4. The anus dilator 100 has almost the 
same construction as that of the anal retractor according to the prior 
embodiment of which is shown in FIG. 4; but the gauge screw is not 
provided therein. Further, it should be noted that the inoculator 4 has 
the same construction as the conventional device illustrated in FIG. 3. 
Therefore, the same numerical references in FIGS. 3 and 4 are given to the 
same elements of the anus dilator 100 and the inoculator 4 in FIG. 6 and 
the explanations for the same elements are omitted here. It should be 
noted, however, that the anus dilator 100 should have a sufficient 
diameter, such that the first and second inosculating sections 52 and 53 
of the inosculating device may easily be inserted. 
According to this embodiment of the inosculating device the inoculator is 
inserted into a cavity with the aid of the dilator 100. Therefore, the 
inoculator can be inserted into the cavity very easily and smoothly, 
because the dilator acts as a guide. 
The function of the inosculating device will be explained below. First, the 
auxiliary appliance 110 is mounted in the anus dilator 100 as explained 
previously. Since the step 111 is provided on the outer circumference of 
the distal top portion 112 of the auxiliary appliance 110, the connecting 
portion of the dilator 100 and the auxiliary appliance 110 is smooth, so 
that the dilator 100 can be easily inserted into the anus and the pain for 
the patient is reduced. 
Next, the anus dilator 100, with the auxiliary appliance 110, is inserted 
into the anus of the patient. After inserting the dilator 100 to a 
predetermined depth, the operator grips the handle 101 to open the valves 
105; then the auxiliary appliance 110 is removed from the dilator 100, 
leaving the dilator 100 in the anus. Then, the inserting portion 50 of the 
inoculator 4 is inserted into the alimentary canal via the anus using the 
dilator 100 as a guide. 
In this way, a bullet shaped distal top portion of the auxiliary appliance 
110 according to the second invention, which is connected to the dilator 
forming a smooth outer surface, is inserted into the anus first and the 
anus is dilated a little by this insertion. Thereafter, the inoculator 4, 
which has a larger diameter on its inserting portion, is inserted, keeping 
the dilated condition of the anus by the dilator 100. Therefore, the 
operator can easily insert the inoculator into a desired portion of a 
cavity and the great pain, which the patient would have experienced if the 
conventional inosculating device was inserted into the anus directly, can 
be remarkably reduced. 
Further, leaving the inserting portion 50 of the inoculator 4 in the anus 
and the portion of the alimentary canal to be treated, the anus dilator 
100 can be removed from the anus. After the dilator 100 is completely 
removed from the anus, the valves 105 of the dilator 100 are opened by 
gripping the handle 101 such that the dilator can be separated from the 
inoculator 4. As stated above, since the valves 105a and 105b are arranged 
to be rotatable about axes extended in an inserting direction of the 
dilator, the dilator 100 can be easily separated from the inoculator 4, 
keeping the condition that the inoculator 4 is still inserted in the anus 
and the alimentary canal. 
According to the inosculating device of this invention, the dilating 
operation of the anus and the insertion of the inosculating device into 
the alimentary canal can be easily conducted by only one operator. That is 
to say, the operator dilates the anus of a patient with one of his or her 
hands, while the same operator can insert the inoculator with the other 
hand very easily. 
After the inosculating operation is finished, the inosculating device 4 is 
removed from the cavity via the anus with the aid of the anus dilator 100 
in the reverse order of the above-explained operation. In this case, the 
removal of the inoculator can also easily be carried out and the pain 
experienced by the patient is extremely reduced the same as in the case of 
insertion. 
The present invention is not limited to the above embodiments. For 
instance, in the above mentioned embodiments, the inserting portion of the 
anal retractor (anus dilator) comprises three plate-like valve members. 
However, the number of valve members is not limited to three, but two or 
four or more valve members may be used unless the valve members function 
in the same manner. Further, the anus dilator according to this invention 
may be used as a guide when forceps or fiber scopes are inserted into the 
anus or the alimentary canal via the anus.