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Experimental ileotubal anastomosis in the sow
Experimental ileotubal anastomosis in the sow M. B. WINGATE, M.D. (Lor;n.), F.R.C.S.(C), F.R.C.S.(E), M.R.C.O.G.* L. WINGATE, B.Sc. (LEEDs) Winnipeg, Manitoba, Canada A technique for restoring luminal patency in occluded Fallopian tubes is described using the sow as an experimental animal. The procedure involved the unilateral construction of an ileotubal conduit following superficial irradiation of the ileal part of the conduit. Healing occurred without scarring and there was evidence that tubal epithelium was replacing irradiated intestinal epithelium. Pregnancy occurred in one of the experimental sows but ended in abortion. A bilateral conduit operation would appear to offer a field for further experimental study.
0 c c L u s I o N of the Fallopian tube is a common finding in the infertile patient.11 In spite of advances in surgical technique and postoperative care, only a small number of treated patients become pregnant/· 10• 14 and success is confined in the main to those procedures which relieve obstruction of the infundibular part of the tube. The need to develop a more successful operative technique has stimulated many experimental studies. These have included resection and reconstruction of the tubes over various materials to maintain patency, and replacement with segments of artery, vein, or amniotic membrane. 1 • 2 • s, 5 • 6 • s, 1 5 Recent interest has centered on the use of an intact isolated ileal segment to replace the damaged Fallopian tube. Using the dog as an experimental animal, Kucharczuk and Green 9 connected the ovarian bursa to the uterine horn by means of an isolated segment of ileum with its blood supply intact, while Charles and associates4 performed a similar study using a reversed seromuscular ileal graft. These workers were able to dem-
onstrate luminal patency in, and survival of, many of the grafts but have not to date reported pregnancy in any of the experimental animals. It is likely that tubal secretions are essential for fertilization and possibly transport of the ovum 12 • 13 and a technique which preserves the Fallopian tube while increasing its luminal size will have a greater chance of success. Method
In this study 6 sows were used, which had littered on two or more occasions and whose average weight was 300 pounds. The animals were prepared preoperatively with intramuscular streptomycin for 2 days and a fluid diet for one day. (Anesthesia was induced with intravenous Thiopental and maintained after intubation with nitrous oxide, oxygen, and halothane.) Under aseptic precautions the abdomen was opened by midline subumbilical incision and a segment of terminal ileum found which would fit against the left Fallopian tube without tension on its vascular arcade. Care was taken that the direction of its peristaltic wave would be toward the uterine horn. This segment, about 10 em. in length, was then isolated with its mesentery and blood supply intact, and the continuity of the gut reestablished anterior to the isolated segment with two layers of chromic 2-0 catgut. The
From the University, Department of Obstetrics and Gynaecology, Winnipeg General Hospital, and the University, Department of Experimental Surgery, the Medical College. *Present address: Dtpartment of Obstetrics and Gynecology, Temple University Hospital, Philadelphia, Pennsylvania 19140.
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lleotubal anastomosis 1177
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Fig. 1. Irradiation of ileal graft with the strontium-90 plaque.
lumen of the ileal loop was irrigated with sterile normal saline until clear washings were obtained. Two incisions were made along the length of the ileal segment and the lower antimesenteric half removed and discarded. The upper half was pinned flat on a sterile wooden board with its luminal surface uppermost, and without tension to its blood supply, and irradiated. A specially constructed strontium-90 plaque was applied to the pinned out segment of the ileum and a total dose of 2,500 rads delivered (Fig. 1). The plaque was not available for the first two procedures and a dose of 1,500 rads was given with a conventional x-ray machine. (The activity contained in the plaque was of the order of 200 me. of strontium-90, giving a dose rate of 7 rads per second at the surface and 6.3 rads per second at a distance of 33 mm. from the surface. The Bremsstrahlung produced in the backing of the plaque was equivalent to the dose rate from approximately 2 mg. of radium.) The right Fallopian tube was excised. A longitudinal incision was made into the upper surface of the left Fallopian tube,
from the uterine hom to the fimbriated end, disturbing the ovarian hood as little as possible. Bleeding points were ligated with plain 4-0 catgut and the irradiated ileal graft apposed longitudinally to the opened Fallopian tube. The cut edges of the ileum and the tube were sutured together with a continuous seromuscular stitch of chromic 4-0 catgut to form an ileotubal conduit. Care was taken to ensure that the stitch did not include the epithelial lining of either tube or ileum; some resection and fashioning of the ileal graft was necessary to obtain a regular luminal diameter at the cornual end of the anastomosis. At the end of the procedure the ileatubal graft lay in position without tension on its vascular supply and the luminal diameter was about twice that of a normal Fallopian tube (Fig. 2). No stents were used to maintain luminal patency and the abdomen was closed in layers. Postoperatively the first two sows were given intramuscular streptomycin for 4 days. Both animals had an adverse reaction to streptomycin and so this procedure was discontinued. The last four animals had an uncomplicated postoperative recovery.
1178 Wingate and Wingate
[Jeccmher 15, I % ~1 ·\n1. J. Obst. & Gynec.
Fig. 2. The completed ileotubal anastomosis.
Results
The first sow was killed one month after operation and before estrus had occurred, in order to determine the viability of the ileatubal graft. No adhesions were found around the operation site, the anastomosis was viable and the conduit patent. Sections were taken at intervals along the length of the anastomosis and the response to radiation and changes in the epithelium of both the Fallopian tube and the ileum were noted (Figs. 3 and 4) . The second animal had a prolonged convalescence and apparent complete recovery did not occur for 3 weeks. Ten weeks later, as estrus had not occurred, this sow was killed. Postmortem examination showed a large organized tuboovarian abscess at the operation site. The third experimental animal came into estrus 8 weeks after operation and was mated. Sixteen days after mating, the sow had an abortion, although, for technical reasons, histologic confirmation could not be obtained. This animal and the three succeeding ones were each mated on two successive occasions but no further pregnancies occurred. Postmortem examination demonstrated patency of the
ileotubal conduit in all these animals. The experimental model has now been changed to dogs as these are less expensive to obtain and maintain. Comment
The use of a viable ileal graft would appear to offer the best chance of success in an operation designed to relieve tubal occlusion and to increase luminal patency, while at the same time retaining as much of the Fallopian tube as possible. The structure of the ileum is in many ways similar to that of the Fa1lopian tube. Both tissues are covered with peritoneum, have longitudinal and circular muscle coats, an autonomic nerve supply, and a nmvoluted mucosa of columnar epithelium. ciliated in the tube and brush-bordered in the ileum. Both structures have peristaltic movement, and the ileal graft should theoretically be capable of aiding transport of the fertilized ovum to the uterus. One of the problems involved in using an ileal graft was that of the mucussecreting goblet cells present in the epithelium. It seemed likely that the production of mucus might interfere with ovular transport
Volume 105 Number 8
lleotubal anastomosis 1179
Fig. 3. Photomicrograph of ileotubal anastomosis in the first sow, showing destruction of ileal epithelium, but persistence of some goblet cells. The epithelium of the Fallopian tube is beginning to grow over the ileal mucosa. (Hematoxylin and eosin. xlOO.)
Fig. 4. Photomicrograph of a different area of the ileotubal anastomosis showing degenerating goblet cells and the absence of ileal epithelium following irradiation. Healthy tubal columnar epithelium can be seen on the left of the photomicrograph. (Hematoxylin and eosin. X400.)
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and so the mucosa of the graft was superficially irradiated. In this way it was hoped to destroy the mucus-secreting cells or considerably reduce the amount of mucus produced. It was also considered possible that irradiation might destroy the ileal epithelium with subsequent replacement by tubal epithelium. Histologic examination of sections of the ileotubal graft taken from the first sow showed the absence of scarring at the anastomotic site, fusion of the musde coats without intervening fibrosis, and a reduction in the amount of mucus-secreting epithelium in the graft when compared vvith nonirradiated ileum. Tubal epithelium was beginning to grow onto the ileal graft to replace the irradiated epithelium, which showed evidence of radiation damage and cell death (Figs. 3 and 4). It was therefore decided
\111.
that in succeeding experiments the amount of radiation should be increa1>ed lo 2,500 rads. One limitation of the technique described i~ the reduction of potential fertilitv inherent in the removal of one Fallopian tube. It will therefore be of interest to perform a bilateral ilcotubal anastomosis to sec whether any ensuing pregnancies continue to term. This preliminary study was carried courtesy of Professor Messervy of the ment of Veterinary Surgery, University tol, England, with a gram from the
United Bristol Hospitals. Mr. Derek Gifford, Principal Physicist, Bristol, carried out the irradiation procedures. It is being continued with a grant from the Medical Research Council of Canada.
REFERENCES
1. Andrews, M. C., and Andrews, W. C.: AM. J. 0BST. & GYNEC. 70: 1232, 1955. 2. Ca.stallo, M. A.: Fertil. & Steril. 1: 435, 1950. 3. Castallo, M. A., and Wainer, A. S.: AM. J. 0BST. & GYNEC. 66: 385, 1953. 4. Charles, A. G., Lakes, J. E., Cohen, M., Fitch, L. B., and Shoemaker, W. C.: Obst. & Gynec. 20: 174, 1962. 5. Davids, A. M., and Bellwin, A.: Fertil. & Steril. 5: 325, 1954. 6. Gepfert, J. R.: AM. J. 0BsT. & GYNEC. 38: 256, 1939. 7. Greenhill, J. P.: AM. J. 0BST. & GYNEC. 72: 516, 1956. 8. Israel, S. L.: Fertil. & Steril. 2: 505, 1951.
out by Departof Bris-
and Green, J. W., Jr.: 72: 528, 1956. Mroueh, A., Glass, R. H., and Buxton, C. Lee: Fertil. & Steril. 18: 80, 1967. Rubin, I.: Uterotubal Insufflation, St. Louis, 1947, The C. V. Mosby Company. Shettles, L.: AM. J. OBsT. & GYNEC. 66: 235, 1953. Shettles, L.: AM. J. 0BsT. & GvNEC. 69: 365, 1955. Siegler, A. M., and Hellman, L. M.: Fertil. & Steril. 14: 300, 1963. Ten Berge, B. S., and Tik Lok, T.: Fertil. & Steril. 5: 339, 1954.
9. Kucharczuk, AM.
10. 11.
12. 13.
14. 15.
J.
J. B.,
0BST. & GYNEC.
0 c c L u s I o N of the Fallopian tube is a common finding in the infertile patient.11 In spite of advances in surgical technique and postoperative care, only a small number of treated patients become pregnant/· 10• 14 and success is confined in the main to those procedures which relieve obstruction of the infundibular part of the tube. The need to develop a more successful operative technique has stimulated many experimental studies. These have included resection and reconstruction of the tubes over various materials to maintain patency, and replacement with segments of artery, vein, or amniotic membrane. 1 • 2 • s, 5 • 6 • s, 1 5 Recent interest has centered on the use of an intact isolated ileal segment to replace the damaged Fallopian tube. Using the dog as an experimental animal, Kucharczuk and Green 9 connected the ovarian bursa to the uterine horn by means of an isolated segment of ileum with its blood supply intact, while Charles and associates4 performed a similar study using a reversed seromuscular ileal graft. These workers were able to dem-
onstrate luminal patency in, and survival of, many of the grafts but have not to date reported pregnancy in any of the experimental animals. It is likely that tubal secretions are essential for fertilization and possibly transport of the ovum 12 • 13 and a technique which preserves the Fallopian tube while increasing its luminal size will have a greater chance of success. Method
In this study 6 sows were used, which had littered on two or more occasions and whose average weight was 300 pounds. The animals were prepared preoperatively with intramuscular streptomycin for 2 days and a fluid diet for one day. (Anesthesia was induced with intravenous Thiopental and maintained after intubation with nitrous oxide, oxygen, and halothane.) Under aseptic precautions the abdomen was opened by midline subumbilical incision and a segment of terminal ileum found which would fit against the left Fallopian tube without tension on its vascular arcade. Care was taken that the direction of its peristaltic wave would be toward the uterine horn. This segment, about 10 em. in length, was then isolated with its mesentery and blood supply intact, and the continuity of the gut reestablished anterior to the isolated segment with two layers of chromic 2-0 catgut. The
From the University, Department of Obstetrics and Gynaecology, Winnipeg General Hospital, and the University, Department of Experimental Surgery, the Medical College. *Present address: Dtpartment of Obstetrics and Gynecology, Temple University Hospital, Philadelphia, Pennsylvania 19140.
1176
lleotubal anastomosis 1177
Volume 105 Number 8
Fig. 1. Irradiation of ileal graft with the strontium-90 plaque.
lumen of the ileal loop was irrigated with sterile normal saline until clear washings were obtained. Two incisions were made along the length of the ileal segment and the lower antimesenteric half removed and discarded. The upper half was pinned flat on a sterile wooden board with its luminal surface uppermost, and without tension to its blood supply, and irradiated. A specially constructed strontium-90 plaque was applied to the pinned out segment of the ileum and a total dose of 2,500 rads delivered (Fig. 1). The plaque was not available for the first two procedures and a dose of 1,500 rads was given with a conventional x-ray machine. (The activity contained in the plaque was of the order of 200 me. of strontium-90, giving a dose rate of 7 rads per second at the surface and 6.3 rads per second at a distance of 33 mm. from the surface. The Bremsstrahlung produced in the backing of the plaque was equivalent to the dose rate from approximately 2 mg. of radium.) The right Fallopian tube was excised. A longitudinal incision was made into the upper surface of the left Fallopian tube,
from the uterine hom to the fimbriated end, disturbing the ovarian hood as little as possible. Bleeding points were ligated with plain 4-0 catgut and the irradiated ileal graft apposed longitudinally to the opened Fallopian tube. The cut edges of the ileum and the tube were sutured together with a continuous seromuscular stitch of chromic 4-0 catgut to form an ileotubal conduit. Care was taken to ensure that the stitch did not include the epithelial lining of either tube or ileum; some resection and fashioning of the ileal graft was necessary to obtain a regular luminal diameter at the cornual end of the anastomosis. At the end of the procedure the ileatubal graft lay in position without tension on its vascular supply and the luminal diameter was about twice that of a normal Fallopian tube (Fig. 2). No stents were used to maintain luminal patency and the abdomen was closed in layers. Postoperatively the first two sows were given intramuscular streptomycin for 4 days. Both animals had an adverse reaction to streptomycin and so this procedure was discontinued. The last four animals had an uncomplicated postoperative recovery.
1178 Wingate and Wingate
[Jeccmher 15, I % ~1 ·\n1. J. Obst. & Gynec.
Fig. 2. The completed ileotubal anastomosis.
Results
The first sow was killed one month after operation and before estrus had occurred, in order to determine the viability of the ileatubal graft. No adhesions were found around the operation site, the anastomosis was viable and the conduit patent. Sections were taken at intervals along the length of the anastomosis and the response to radiation and changes in the epithelium of both the Fallopian tube and the ileum were noted (Figs. 3 and 4) . The second animal had a prolonged convalescence and apparent complete recovery did not occur for 3 weeks. Ten weeks later, as estrus had not occurred, this sow was killed. Postmortem examination showed a large organized tuboovarian abscess at the operation site. The third experimental animal came into estrus 8 weeks after operation and was mated. Sixteen days after mating, the sow had an abortion, although, for technical reasons, histologic confirmation could not be obtained. This animal and the three succeeding ones were each mated on two successive occasions but no further pregnancies occurred. Postmortem examination demonstrated patency of the
ileotubal conduit in all these animals. The experimental model has now been changed to dogs as these are less expensive to obtain and maintain. Comment
The use of a viable ileal graft would appear to offer the best chance of success in an operation designed to relieve tubal occlusion and to increase luminal patency, while at the same time retaining as much of the Fallopian tube as possible. The structure of the ileum is in many ways similar to that of the Fa1lopian tube. Both tissues are covered with peritoneum, have longitudinal and circular muscle coats, an autonomic nerve supply, and a nmvoluted mucosa of columnar epithelium. ciliated in the tube and brush-bordered in the ileum. Both structures have peristaltic movement, and the ileal graft should theoretically be capable of aiding transport of the fertilized ovum to the uterus. One of the problems involved in using an ileal graft was that of the mucussecreting goblet cells present in the epithelium. It seemed likely that the production of mucus might interfere with ovular transport
Volume 105 Number 8
lleotubal anastomosis 1179
Fig. 3. Photomicrograph of ileotubal anastomosis in the first sow, showing destruction of ileal epithelium, but persistence of some goblet cells. The epithelium of the Fallopian tube is beginning to grow over the ileal mucosa. (Hematoxylin and eosin. xlOO.)
Fig. 4. Photomicrograph of a different area of the ileotubal anastomosis showing degenerating goblet cells and the absence of ileal epithelium following irradiation. Healthy tubal columnar epithelium can be seen on the left of the photomicrograph. (Hematoxylin and eosin. X400.)
1180
lkeemher l:i. l96~r J Ob.;L & Gynn·
Wingate and Wingate
and so the mucosa of the graft was superficially irradiated. In this way it was hoped to destroy the mucus-secreting cells or considerably reduce the amount of mucus produced. It was also considered possible that irradiation might destroy the ileal epithelium with subsequent replacement by tubal epithelium. Histologic examination of sections of the ileotubal graft taken from the first sow showed the absence of scarring at the anastomotic site, fusion of the musde coats without intervening fibrosis, and a reduction in the amount of mucus-secreting epithelium in the graft when compared vvith nonirradiated ileum. Tubal epithelium was beginning to grow onto the ileal graft to replace the irradiated epithelium, which showed evidence of radiation damage and cell death (Figs. 3 and 4). It was therefore decided
\111.
that in succeeding experiments the amount of radiation should be increa1>ed lo 2,500 rads. One limitation of the technique described i~ the reduction of potential fertilitv inherent in the removal of one Fallopian tube. It will therefore be of interest to perform a bilateral ilcotubal anastomosis to sec whether any ensuing pregnancies continue to term. This preliminary study was carried courtesy of Professor Messervy of the ment of Veterinary Surgery, University tol, England, with a gram from the
United Bristol Hospitals. Mr. Derek Gifford, Principal Physicist, Bristol, carried out the irradiation procedures. It is being continued with a grant from the Medical Research Council of Canada.
REFERENCES
1. Andrews, M. C., and Andrews, W. C.: AM. J. 0BST. & GYNEC. 70: 1232, 1955. 2. Ca.stallo, M. A.: Fertil. & Steril. 1: 435, 1950. 3. Castallo, M. A., and Wainer, A. S.: AM. J. 0BST. & GYNEC. 66: 385, 1953. 4. Charles, A. G., Lakes, J. E., Cohen, M., Fitch, L. B., and Shoemaker, W. C.: Obst. & Gynec. 20: 174, 1962. 5. Davids, A. M., and Bellwin, A.: Fertil. & Steril. 5: 325, 1954. 6. Gepfert, J. R.: AM. J. 0BsT. & GYNEC. 38: 256, 1939. 7. Greenhill, J. P.: AM. J. 0BST. & GYNEC. 72: 516, 1956. 8. Israel, S. L.: Fertil. & Steril. 2: 505, 1951.
out by Departof Bris-
and Green, J. W., Jr.: 72: 528, 1956. Mroueh, A., Glass, R. H., and Buxton, C. Lee: Fertil. & Steril. 18: 80, 1967. Rubin, I.: Uterotubal Insufflation, St. Louis, 1947, The C. V. Mosby Company. Shettles, L.: AM. J. OBsT. & GYNEC. 66: 235, 1953. Shettles, L.: AM. J. 0BsT. & GvNEC. 69: 365, 1955. Siegler, A. M., and Hellman, L. M.: Fertil. & Steril. 14: 300, 1963. Ten Berge, B. S., and Tik Lok, T.: Fertil. & Steril. 5: 339, 1954.
9. Kucharczuk, AM.
10. 11.
12. 13.
14. 15.
J.
J. B.,
0BST. & GYNEC.