bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental microvenous reconstructions with Gore‐Tex polytetrafluoroethylene prostheses implanted by means of the sleeve anastomotic technique
Authors: Van Der Lei B. , Bartels H. L. , Dijk F. , Schakenraad J. M. , Nieuwenhuis P. , Robinson P. H.
Published: March 2007

Polytetrafluoroethylene (PTFE) prostheses (Gore‐Tex® ID, 1 mm; length, 5–7 mm; wall thickness, 0.2 mm; fibril length, 30 μm, n = 28) were implanted into the rat femoral vein by means of the sleeve anastomotic technique to enhance the patency rate. In the control group, PTFE prostheses (n = 8) were implanted by means of the end‐to‐end technique. In the experimental group patency and healing of the PTFE prostheses were evaluated at 1 day (n = 4), 1 week (n = 6), 3 weeks (n = 6), 6 weeks (n = 6), and 12 weeks (n = 6) after implantation by means of macroscopic inspection and routine light and scanning electron microscopy. All prostheses, except one at 1 week after implantation, were patent at the time of removal. All of the microvenous prostheses were completely covered by an endothelial layer at 3, 6, and 12 weeks after implantation. Occasionally some smooth muscle‐like cells could be found underneath this endothelial layer, but stenosis was never observed at the anastomotic sites. Only scarce tissue ingrowth was observed in the wall of the PTFE prostheses. In the control group, all prostheses, except one prosthesis after 3 weeks, were found to be occluded. An occlusive mural thrombus was found firmly attached at the anastomoses at 1 day, and an organized thrombus at 3 weeks after implantation. The patent prosthesis demonstrated complete endothelial healing. These results demonstrate the importance of the sleeve anastomotic technique and the potential of PTFE prostheses as a microvenous conduit when implanted by means of the sleeve anastomotic technique in experimental reconstructive microvascular procedures.
Carotid bifurcation reconstruction using y‐shaped microvascular grafts: An experimental study in rats
Authors: Morimoto Tetsuya , Imhof Hans Georg , Wiestler Otmar D.
Published: March 2007

Reconstruction of the carotid bifurcation was performed in rats using y‐shaped microvascular grafts in an attempt to examine the feasibility of using such grafts in intracranial vascular reconstruction, especially for vessels with bifurcations. Twenty y‐shaped microarterial grafts were obtained from the carotid bifurcation of donor rats, while 20 y‐shaped microvenous grafts were obtained from the femoral veins of the rats. The patency rate of arterial grafts and venous grafts were 75% and 97%, respectively. Anastomotic aneurysms frequently occurred in both arterial grafts (45%) and venous grafts (60%). Results of histological examinations concluded that these aneurysms were false aneurysms. We discuss the reasons for aneurysm formation and technical issues that might improve the experimental results with regard to patency and aneurysm formation.
Some factors affecting the survival of venous flaps: An experimental study
Authors: Yuen Q. M. , Leung P. C.
Published: March 2007

The inferior epigastric venous flap of the rat was chosen for experimental studies of vascular flow alterations. The long saphenous vein was not selected for use; preliminary studies involving forced retrograde injection demonstrated that it drains blood primarily from the leg and foot, not from its overlying skin. Eight different flap designs were studied: group A, saphenous flap, simple isolation with pedicle; group B, inferior epigastric flap, simple isolation with pedicle; group C, inferior epigastric flap, simple isolation with interpositioned Silastic sheet; group D, cross‐transferred venous pressure arterial flap; group E, cross‐transferred, arterialised venous flap; group F, arterialized venous flap, in which arterial blood was shunted away via the main vein; group G, cross‐transferred venous pressure venous flap; and group K, control, nonvascularized flap. Three more groups (H, I, J) were introduced by repeating the flap designs of groups E, F, and G but preceded by forced perfusion of the venous system using 5 cc of normal saline at 200 mm Hg. The best results were obtained with groups B, C, E, H, and I. The other flaps necrosed. The results are discussed based on the assumption that true retrograde venous blood flow does occur.
Experimental study on microvascular anastomosis using a dissolvable stent support in the lumen
Authors: Cong Zhang , Nongxuan Tang , Changfu Zheng , Yuanwei Xu , Tongde Wang
Published: March 2007

A new method for microvascular anastomosis was developed and compared with conventional techniques, using the rabbit femoral artery. A dissolvable stent biomaterial was placed in the lumen to expose the vessel walls clearly, so that the quality of anastomosis could be improved. The results showed no significant difference in immediate and late patency rates between the methods, but the use of the stent resulted in faster repair, less dilation at the anastomosis, and less narrowing of the distal segments, causing apparently minor hemodynamic disturbance, with increased blood flow distally. Minor damage to the vessel walls and rapid healing of the wound were verified by histologic evaluation.
Inter‐ and intraobserver reliability of walking‐track analysis used to assess sciatic nerve function in rats
Authors: Brown C. J. , Evans P. J. , Mackinnon S. E. , Bain J. R. , Makino A. P. , Hunter D. A. , Hare G.
Published: March 2007

The inter‐ and intraobserver reliability of the walking‐track analysis of sciatic nerve function in the rat was assessed. Twenty‐five walking tracks were assessed on three different occasions by four observers. Whereas the interobserver reliability was found to be excellent (r = 0.92), the intraobserver reliability was only satisfactory (r = 0.53 to r = 0.76). Walking‐track analysis provides a noninvasive technique to assess function recovery in the rat, with excellent intraobserver reliability demonstrated. The lower intraobserver reliability suggests limitations to this new measurement technique.
Experimental and clinical free cutaneous transfers in the dog
Authors: Miller Craig C. , Fowler J. David , Bowen C. Vaughan A. , Chang Peter
Published: March 2007

Various reconstructive techniques have been applied to the management of difficult wounds in the dog. Wounds in the distal extremities and on the face are hard to manage by conventional methods. A free cutaneous flap, based on the superficial cervical vessels, was developed and used in a series of experimental and clinical cases. Six of eight experimental orthotopic transfers survived. The two failures were thought to be related to technical error. The seven flaps, used in clinical cases, all survived and successfully resolved the dogs' clinical problems.
Axial pattern skin flaps in cats
Authors: Remedios Audrey M. , Bauer Michael S. , Bowen C. Vaughan A. , Fowler J. David
Published: March 2007

The major direct cutaneous vessels identified in the cat include the omocervical, thoracodorsal, deep circumflex iliac, and caudal superficial epigastric arteries. Axial pattern skin flaps based on the thoracodorsal and caudal superficial epigastric arteries have been developed in cats. Rotation of these flaps as islands allows skin coverage to the carpus and metatarsus, respectively. The thoracodorsal and caudal superficial epigastric flaps provide a practical, one‐step option in the reconstruction of large skin defects involving the distal extremities of cats.
Experimental cutaneous free flap transfers in the horse
Authors: Lees Michael J. , Fretz Peter B. , Bowen C. Vaughan A. , Leach Douglas H.
Published: March 2007

Equine limb wounds often heal slowly by epithelialization, and large scars are a frequent end result. In some ways, they resemble the wound associated with human tibial injuries. The literature indicates that previous investigators have failed to transfer free skin flaps successfully in the horse. In this paper, we review our experimental work with the deep circumflex iliac flap in the horse. Dissections of 20 cadavers confirmed the anatomical consistency of the flap. Four flaps survived well when elevated as island flaps, but five orthotopic and nine heterotopic free flap transfers all failed. The cause of failure is still unknown, but our experiments suggested that the horse must be highly susceptible to ischemic reperfusion injury.
Identification of muscle flaps in small animals
Authors: Gregory Clare R. , Gourley Ira M.
Published: March 2007

Muscle flaps in small animals have been used quite frequently in experimental research. Their use in clinical veterinary surgery, however, has not yet been extensively explored. This paper describes the anatomy and clinical use of some of the muscle flaps that have been investigated and used in small animals.
Free bowel transfer for esophageal reconstruction in the dog
Authors: Holmberg David L. , Kuzma Alan B. , Miller Craig W.
Published: March 2007

Clinical esophageal reconstruction in dogs is generally limited to the repair of small segments of cervical and terminal thoracic esophagus. The attempt was made to develop a procedure for the replacement of the entire thoracic esophagus. Three groups of dogs were used for microvascular colon transfers. Five dogs received orthotopic colon autografts. A segment of cervical esophagus was replaced in three dogs, and the entire thoracic esophagus was bypassed in six dogs. The orthotopic grafts worked well and the surviving dogs had normal stools within 48 hr of surgery. The cervical grafts all remained viable, and dogs were able to drink normally and swallow gruel from elevated bowls. Chronic regurgitation of solid food due to inadequate graft motility was an unresolved problem. All thoracic esophageal bypass grafts failed because of mechanical kinking of the vascular pedicles and leakage.
Failure to obtain long‐term patency after implantation of fibrous polyurethane prostheses in the carotid arteries of rabbits
Authors: Hess Frits , Steeghs Suzanne , Jerusalem Christoph , Braun Bernd , Grande Peter
Published: March 2007

Fibrous polyurethane prostheses were implanted in the carotid arteries and aortae of New Zealand white (NZW) and Chinchilla (CHIN) rabbits. No immediate post‐implantation patency was obtained after implantation in the carotid arteries in NZW rabbits. In CHIN rabbits patency up to 1 week was obtained after carotid implantation. Attempts to increase patency rates by administration of 20 mg/kg body weight/day of both dipyridamol (DIP) and acetyl‐salicylic acid (ASA) p.o., starting the week before implantation, had an adverse effect; prostheses became occluded within a few hours after implantation. Coagulation tests (Lee and White, Am J Med Sci 145:495–503, 1913) carried out with blood drawn from CHIN rabbits revealed hypercoaguability after administration of either 10 or 20 mg/kg body weight/day of both DIP and ASA compared to pre‐medication values. Prostheses implanted in the aortae of both strains remained patent without anti‐platelet‐aggregation therapy for a 3‐month observation period. It is concluded that in the NZW rabbit carotid implantation was not successful due to severe spasmic reactions and that in CHIN rabbits only very short‐term patency could be obtained both with and without administration of 10 or 20 mg/kg body weight/day medication DIP and ASA.
Toe transfer for congenital hand defects
Authors: Eaton Charles J. , Lister Graham D.
Published: March 2007

Toe‐to‐hand transfer is a well‐established reconstructive option for certain congenital hand anomalies. It is the only technique which can add growth potential to the immature skeleton. Toe transfer is best suited for constriction ring amputations, which have relatively normal proximal anatomy. Transfers should be performed early in life to avoid lack of cortical integration of the new part. Anatomic variations of both hand and foot are often encountered, which influence both operative approach and functional prognosis. Indications, techniques, and complications are reviewed.
Free tissue transfer for reconstruction of traumatic limb injuries in children
Authors: Arnez Zoran M. , Hanel Douglas P.
Published: March 2007

Free tissue transfer was used for the reconstruction of soft tissue defects in 94 children. Of the 127 procedures performed, the latissimus dorsi, scapular skin, lateral arm skin, rectus abdominis, and gracilis were used with the greatest frequency. The microsurgical success rate was 96%. Microsurgical failures were repeated, successfully, and in all cases the limbs were salvaged. Other than having to deal with decreased vessel size and avoiding continuous suture lines, there appears to be little difference in technique or outcome of free tissue transfer when compared to adults.
Replantation in children
Authors: Taras John S. , Nunley James A. , Urbaniak James R. , Goldner Richard D. , Fitch Robert D.
Published: March 2007

The authors have replanted 162 parts in 120 children over the past 15 years. The youngest patient, undergoing successful replantation, was aged 7 months, 3 weeks. Unlike an adult, any child suffering a traumatic amputation should be considered for a possible replantation. Replantation should consist of minimal bone shortening to preserve epiphyseal plates, with repair of all severed structures. Longitudinal K‐wires usually provide adequate fixation. Our survival rate for complete replantation in children under the age of 16 years is 77%. Long‐term study showed that continued skeletal growth occurred and the digit attained 81% of normal longitudinal length at maturity. Recovery of sensibility in the replanted digit is nearly as good as for isolated digital nerve repair. Patient and parent satisfaction is high when replantation is successful, with uniform approval of the extensive effort required.
Laser doppler bone probe: An experimental study in dogs
Authors: Schuurman Arnold H. , Bos Kurt E.
Published: March 2007

Immediate reintervention is necessary when vascular insufficiency is suspected in free bone transfers. We tested the reliability of the laser doppler bone probe in recording steady state and arterial and venous occlusion. During steady state the flux signal was not constant but fluctuated. During arterial occlusion an immediate and reproducible decrease in flux signal was seen. No evident changes were seen during venous occlusion. These results have clinical importance in monitoring free bone transfers.
Effects of venous hypertension on rabbit free flap survival
Authors: Rooks Michael D. , Gould John S. , Masear Victoria , Powell Jack H. , Gould Sheryl
Published: March 2007

A two‐stage project was developed to study the effect of increased venous pressure on blood flow and survival in microvascular free tissue transfers. A rabbit epigastric fasciocutaneous free flap model was used. The blood flow in the rabbit epigastric free flap is 1.07 ± 0.06 ml/min. The average venous pressure is 8.6 ± 1.7 cm water. A logarithmic relationship between blood flow and venous pressure was demonstrated, with a statistically significant decrease in blood flow to 20‐35% of the control values when the venous pressure rose above 28‐30 cm water. This study stands in support of the tolerance by free tissue transfers of pressures below this range. The results further show a positive correlation between increasing venous pressure and free flap failure.
Microvascular transfer of anterior and posterior gracilis muscles in rats
Authors: Yim Kenneth K. , Lineaweaver William C. , Siko Peter P. , Buncke Harry J.
Published: March 2007

A microvascular free muscle flap in rats using the anterior and posterior gracilis muscles with femoral vessels as its pedicle is presented. The gracilis muscles form a single unit supplied by the muscular branch artery and vein, averaging 0.3 mm and 0.4 mm in diameter, respectively. These small sizes preclude their use in transplantation. However, the muscular branch vessels in continuity with the femoral vessels can be used for the vascular pedicle in this muscle transplant. This muscle flap was transplanted to the contralateral femoral vessels by end‐to‐end anastomosis in 15 rats. Thirteen animals survived and 11 flaps were viable at 3 days for a success rate of 85%. The gracilis flaps averaged 674 mg in weight, 1.87 cm × 1.36 cm in size, and 7.23 mm in pedicle length. This free muscle flap model is reliable, relatively easy to perform, and provides adequate muscle bulk for pharmacologic and biochemical studies in transplanted muscle. No lower extremity complications were noted following femoral vessel ligations.
Topically applied antithrombotic agents offer a new therapeutic approach to the prevention of microvascular thrombosis
Authors: Cooley Brian C. , Gould John S.
Published: March 2007

In the quest to develop optimal antithrombotic therapies for reconstructive microsurgery, with concomitant minimization of patient risk for generalized hemorrhage, surgeons have been turning to localized intraarterial delivery of various agents. An extension of this direction is to design agents that bind specifically to the site of thrombogenesis and effectively inhibit or prevent the buildup of thrombotic components. Progress in this direction must make use of the latest developments in the molecular understanding of coagulation, platelet adhesion/aggregation, and fibrinolytic processes. This article reviews pertinent developments in the biochemical understanding of thrombosis and discusses current avenues of investigation in the development of topically applied agents that help prevent microvascular thrombotic occlusion.
Effect of desmopressin on vein graft patency in a microvascular model
Authors: Kon Neal D. , Mills Stephen A. , Andrews Cynthia A. , Miller Larry R. , Cordell A. Robert
Published: March 2007

Desmopressin acetate decreases blood loss after cardiac surgery by activating platelets. We studied whether this effect was detrimental to small‐caliber vein grafts in rats. Thirty minutes before femoral artery grafting with 0.75‐mm‐diameter reverse autogenous saphenous vein grafts, 20 rats received desmopressin acetate intravenously at 1.O pglkg over 10 minutes, and 20 control rats received normal saline intravenously over 10 minutes. In each group, 10 rats received a 6‐mm‐long graft and 10 an 18‐mm‐long graft. Graft patency was evaluated at 20 minutes, 24 hours, and 30 days. Intimal thickening was assessed by light and scanning electron microscopy. At 30 days, 9 short grafts and 8 long grafts in the desmopressin‐treated group were patent, whereas only 8 short control grafts and only 6 long control grafts were patent. Intimal thickening and platelet deposition were the same in both groups. These data show no detrimental effects of desmopressin acetate on saphenous vein graft patency.
A technique for hepatopancreaticoduodenal cluster transplantation in the rat
Authors: Knoop M. , Steffen R. , Neuhaus P.
Published: March 2007

A new technique for combined hepatopancreaticoduodenal transplantation in the rat is described. The composite cluster graft consists of an orthotopic arterialized liver graft in anatomical continuity with the pancreaticoduodenal part that is placed heterotopically into the recipient. A separate arterial anastomosis of the liver and a bile duct anastomosis are not necessary, since these structures are left intact in the hepatoduodenal ligament. Bile and exocrine pancreas secretions drain over the duodenal conduit of the graft into the recipient jejunum via an end‐to‐side anastomosis. This model adds a new transplantation technique to existing microsurgical models.
Nerve regeneration through a two‐ply biodegradable nerve guide in the rat and the influence of ACTH4‐9 nerve growth factor
Authors: Robinson Peter H. , Van Der Lei Berend , Hoppen Henk J. , Leenslag Jan W. , Pennings Albert J. , Nieuwenhuis Paul
Published: March 2007

Biodegradable polyurethane‐based (PU) nerve guides, instilled with or without ACTH4‐9 analog (a melanocortin) were used for bridging an 8 mm gap in the rat sciatic nerve and were evaluated for function and histological appearance after 16 weeks of implantation. Autologous nerve grafts functioned as controls. The guides successfully enabled the sciatic nerve to regenerate across the 8 mm gap, thus effectively reestablishing the contact between the proximal and distal nerve ends. The mean conduction velocity, motor latency, and muscle action potentials of all the nerve guides did not differ significantly from the autografts. The histological quality of the regeneration in the nerve guides was significantly better than in the autografts; in the nerve guides, a well‐defined nerve cable of normal architecture had regenerated without extensive endoneural scarring as seen in the autografts. ACTH4‐9 instilled in the nerve guides showed a slight, but significant, increase in the number of myelinated axons. It is concluded that biodegradable PU nerve guides result in similar functional recovery when compared with autografts, but their histological quality is significantly better. ACTH4‐9 showed only slight, but significant, improved nerve growth promoting activity. Therefore biodegradable PU nerve guides with ACTH4‐9 would appear to be promising alternatives to autografts for bridging nerve defects.
A scanning electron microscopic study of arterial endothelial repair under turbulent flow conditions
Authors: Kirse Daniel J. , Young Paul H.
Published: March 2007

In order to study the role of hemodynamic factors on the healing and native morphology of endothelium in vivo, turbulent arterial flow was created using a loop bypass model, with and without occlusion in the recipient vessel. In this model, several different patterns of turbulent arterial blood flow resulted. The scanning electron microscope (SEM) was used to evaluate endothelial morphology in the area of the anastomoses at 3 and 14 days post‐operatively. Morphological changes in the native endothelium along the recipient vessel correlated well with the direction of blood flow and predicted patterns of turbulence. The morphology of the native endothelium was altered to reflect the direction and pattern (laminar versus turbulent) of blood flow by 3 days post‐operatively. Based on endothelial morphology, very narrow zones of separation could be demonstrated between areas of laminar and turbulent blood flow. The degree of reendothelialization across the suture itself was greatly variable at 3 days and there seemed to be no relationship to the location of turbulent flow.
Osmotic complications of low‐molecular‐weight dextran therapy in free flap surgery
Authors: Hardin Charles K. , Kirk William C. , Pederson William C.
Published: March 2007

Low‐molecular‐weight dextran is utilized by many microsurgeons after free tissue transfer for its beneficial effects on the microcirculation. While it is generally felt to have a low rate of complications, severe complications secondary to dextran's osmotic effects may occur. We report here on two cases in which therapy with low‐molecular‐weight dextran was strongly implicated as a causative factor in major complications. These cases and their background are reviewed. Guidelines for the safe administration of this agent in patients post free‐tissue transfer are discussed.
Lower extremity reconstruction using a long‐cryopreserved venous allograft for free flap venous outflow
Authors: Liang Marc D. , Narayanan Krishna , Ramasastry Sai S. , Stofman Guy
Published: March 2007

Vein grafts are used frequently in microvascular surgery, but an adequate supply of autogenous veins is not always available. The search for an ideal substitute for autogenous vein continues. We present a case of lower extremity reconstruction made difficult by lack of suitable autogenous vein for venous outflow from a rectus abdominus free flap. A 36 cm cryopreserved allograft saphenous vein was used on an emergency basis for this problem. © Wiley‐Liss, Inc.
Effect of treated infection on microvascular anastomosis
Authors: Luk Keith O. K. , Huang Li , Liu Ke , Chow S. P.
Published: March 2007

The effect of established infection with penicillin‐resistant Staphylococcus aureus on microarterial and microvenous anastomosis was studied in a rat experimental model. The infection was treated with wound debridement and systemic antibiotics at the time of the surgical procedure. It was found that the patency rate of microarterial repairs at 10–14 days was 95.1%. Veins were less resistant to infection than arteries. Two types of vein involvement were found. These were classified according to the degree of thrombosis resulting from endophlebitis. The patency rate of anastomoses performed on the more mildly infected veins was 56.5% and that on the more severely infected veins was 0%. © Wiley‐Liss, Inc.
Fertility and histology after rabbit ovarian wedge resection with CO2 laser or electrocautery using posterior reconstruction with nylon or polyglactin sutures
Authors: Rivera Baldomero Arnau , Guix Manuel , Esteban‐Altirriba J. , Viscasillas Pedro
Published: March 2007

In an experimental study in rabbits, the CO2 laser and electrocautery were compared in performing microsurgical ovarian wedge resection; polyglactin and nylon sutures were compared for ovarian reconstruction. Histologic reaction, adhesion formation, and functional parameters (number of corpora lutea, number of pregnancies, nidation index) were evaluated 30 and 90 days postoperatively. Thirty days after surgery, the tissue inflammatory response was very similar in the four groups; fibrosis was not detected. Significant reductions (P<0.01) were found for the experimental (operated right ovary) vs. the control (unoperated left ovary) groups when comparing the number of corpora lutea and the number of pregnancies. No significant differences in the nidation index were demonstrated. Adhesion formation was not different between any of the experimental procedures; adhesions were not detected in the control ovaries. At 90 days, the polyglactin suture was entirely absorbed and no inflammatory reaction persisted. Minimal giant cell infiltration was found around the nylon suture. The histologic differences between the two sutures were statistically significant (P<0.02). No fibrosis was observed. The functional parameters did not reveal statistically significant differences between the two sutures. © Wiley‐Liss, Inc.
New method of surgical treatment of blood vessel lesions
Authors: Androsov P. I. , Ellis F. Henry
Published: March 2007

Professor Androsov's articles should be of considerable interest to American surgeons, representing as they do a new freedom in the exchange of ideas with the medical profession of the Soviet Union. In recent years no Russian surgeon has sought publication of original work in surgical journals of this country.

Early last fall I visited Professor Androsov in Moscow at the Sklifosovsky Institute, a hospital made famous by the late Professor Yudin. I was impressed by the work that he and his associates were doing in peripheral vascular surgery and in the reconstruction of lye burns of the esophagus. Professor Androsov was extremely hospitable and showed a keen interest in the freer exchange of knowledge between American and Soviet surgeons. He and his staff evinced a friendly interest in American medical institutions as a result of Professor Yudin's visit to the Mayo Clinic and other institutions in this country in former years.

Let us hope that other Soviet surgeons will follow Professor Androsov's lead in submitting to us from time to time reports of their work. © 1992 Wiley‐Liss, Inc.
Surgical technique for combined liver/intestine transplantation in rats
Authors: Zhong Robert , He Gang , Sakai Yoshiraru , McAlister Vivian , Zhang Zheng , Duff John , Stiller Calvin , Grant David
Published: March 2007

Simultaneous liver transplantation may reduce the risk of intestinal transplant rejection. We have recently developed two new models of combined liver/intenstine transplantation (LIT) in the rat to study this phenomenon. Herein, we report our experience with LIT using a single donor (SD) or multiple donors (MD). Large volumes of fluid were required to prevent a drop in the mean arterial pressure during the anhepatic phase in the SD recipients. Many of the SD recipients died of intraoperative hypovolemic shock (57%). The MD recipients had a shorter anhepatic time (12 ± 1 minutes vs.17 ± 2 minutes; P<0.01) and a shorter warm intestinal ischemia time (15 ± 1 minutes vs.32 ± 2 minutes; P<0.01). Operative mortality rates were much lower in the MD recipients (10% vs.68%; P<0.01). The long‐term survival rate using MD was 71% at 1 month. Graft function was normal in the long‐term survivors. LIT with MD provides a good model to study the immunological effects of multivisceral grafting. © 1992 Wiley‐Liss, Inc.
The effect of venous flow alterations upon patency of rat femoral vein anastomoses
Authors: Cooley Brian C. , Gould John S.
Published: March 2007

The rat femoral vein has become a standard model for laboratory training in microvascular anastomotic technique as well as for research investigations into factors affecting venous patency. This study examined the short‐term patency (1 and 7 days) of rat vein anastomoses. The influences upon patency of epigastric flap creation and distal femoral vessel ligation (epigastric flow only) were explored. In a separate experiment, blood flow from the femoral vein was determined through catheter collection of venous efflux; the influences of island epigastric flap creation and distal femoral ligation on flow rates were explored. It was found that 82% of basic femoral vein anastomoses were patent at one day, while 100% of anastomoses associated with an epigastric flap and ligated/transected distal femoral vessel circulation (creating a low‐tension anastomosis) were patent (P<0.01). With distal femoral vessel ligation and no transection (normal tension at the repair), anastomoses were patent in 90% of the veins when an epigastric flap was also raised, and in 60% when a flap was not created. When a flap was raised without disturbing the distal femoral circulation, vein patency was 75% at one day. When the vein anastomosis was performed with distal femoral vein ligation, the patency rate was 50%. All veins patent at 1 day were also patent at 7 days post‐op; 96% of veins clotted at 1 day were found to be patent at 7 days. The venous efflux was not found to vary significantly when an epigastric flap was raised. These results indicate an increase in patency through reduction of longitudinal tension and suggest that island/free flaps have a beneficial influence upon the prevention of venous occlusion. The high rate of recanalization in thrombosed veins indicates a potential source of error in previous studies in which vein patency was evaluated only at longer postoperative times. © 1992 Wiley‐Liss, Inc.
Results after repair of traumatic arterial damage in the forearm
Authors: Daoutis N. , Gerostathopoulos N. , Bouchlis G. , Efstathopoulos D. , Misitzis D. , Anagnostou S. , Vasiliadiw A.
Published: March 2007

Eighty‐three patients, with 96 instances of radial or ulnar arterial damage, were treated over a four‐year period using microsurgical techniques. Thirty‐one patients, with 43 arterial repairs, were available for evaluation. In the 14 patients with a single arterial repair, 4 resulted in thrombosis (71.5% success rate). When both arteries required repair, our success rate was 75.9%, with 7 thromboses. The overall success rate was 74.5%. We attribute the high patency rate to strict microsurgical technique, the repair of the vessels in the early stages after trauma, and the use of vein grafts after complete resection of the damaged portion of the vessel. © Wiley‐Liss, Inc.
Clinical analysis and evaluation of the function of replanted and revascularized parts of the upper limb
Authors: Daoutis N. , Gerostathopoulos N. , Bouchlis G. , Efstaphopoulos D. , Misitzis D. , Anagnostou S. , Gianakopoulos P.
Published: March 2007

During the past four years, we have attempted to replant and revascularize 57 hands and fingers in 43 patients. The total success rate was 81 %. Replantation of hands severed cleanly (guillotine type) and those with slight local crush injuries had the highest success rate. As for hand function, amputations at zones III and IV with end‐to‐end suturing of the tendons and nerves presented the highest degree of function when evaluated objectively and subjectively. All patients presented a high degree of satisfaction with the outcome of the Operation. © Wiley‐Liss, Inc.
Post‐discectomy perineural fibrosis: Comparison of conventional versus microsurgical techniques
Authors: Touliatos Alexandros S. , Soucacos Panayotis N. , Beris Alexandros E.
Published: March 2007

The lumbar spines of twenty‐one dogs were used as an experimental model. The animals were divided into three groups. In the first group, selective dam age to the perimeningeal blood vessels was induced and the resultant he‐matoma was left untouched in the spinal canal. In the second group, the posterior longitudinal ligament was incised, and in the third group, the poste rior longitudinal ligament was incised and damage induced to the peri meningeal blood vessels. The pathology examination revealed: (1) the he‐matoma itself did not lead to the formation of perineural fibrosis, (2) the incision of the posterior longitudinal ligament led to the formation of a limited amount of fibrosis, and (3) the coexistence of hematoma and incision of the posterior longitudinal ligament led to the formation of extensive perineural fibrosis. When discs are removed using microsurgical techniques, it is possi ble to avoid the formation of the postoperative hematoma and consequently to eliminate the perineural fibrosis. © Wiley‐Liss, Inc.
Experimental Evaluation of the length of microvenous grafts under normal tension
Authors: Beris Alexandros E. , Soucacos Panayotis N. , Touliatos Alexandros S.
Published: March 2007

Four groups of microvenous grafts of 2, 4, 6, and 10 cm were used to deter mine whether length under normal tension affects patency rates in bridging arterial defects. Tension was evaluated by allowing the grafts to assume their normal orientation and length by filling them with blood, under physiological pressure, after the completion of the proximal anastomosis. The length was estimated through the normal range of motion such that the graft would not be too loose and/or tortuous following final anastomosis. The patency rates in the four length groups of this study ranged between 80% and 83%, with no sta tistical difference between groups. No statistically significant correlation was found between graft length and patency rate. It was concluded that the length of venous autografts does not affect patency. © Wiley‐Liss, Inc.
Short‐ and long‐term evaluation of arteriovenous fistulas for chronic hemodialysis
Authors: Cassioumis Diamantis , Fatouros Michael S. , Siamopoulos Kostas C. , Giannoukas Athanasios D.
Published: March 2007

One hundred ninety‐three internal arteriovenous (A‐V) fistulas were performed on patients with renal failure in the last eleven years. The A‐V fistulas were divided on the basis of the following: side‐to‐side between the radial artery and cephalic vein (157 cases); end‐to‐side between the cephalic vein and radial artery (11 cases); end‐to‐end between the radial artery and cephalic vein (5 cases); A‐V fistulas between the brachial artery and the cephalic, basilic or medial cubital vein (20 cases). The side‐to‐side A‐V fistulas achieved an immediate patency in 88% of cases, lower than each of the other groups. However, the subsequent long‐term failure rate was less than the other groups. In addition, satisfactory function was maintained at a high level (93%) during the follow‐up period. The end‐to‐side and end‐to‐end A‐V fistulas showed higher percentages of immediate patency (90% and 100%, respectively), although they were used more often on patients with vascular problems. Diabetic nephropathy was the main factor associated with thrombosis Of A‐V fistulas. © Wiley‐Liss, Inc.
Neck resurfacing with free TRAM flap
Authors: Economides Nicholas G. , Ferrell Thad H.
Published: March 2007

Anterior neck defects are best reconstructed with flaps, to avoid contractures and extensive scarring. Local or distal flaps are hampered by significant donor site disability. The development of the TRAM flap for breast reconstruction has improved our armamentarium in reconstructive surgery. This paper purports to demonstrate the superiority of the free bilateral TRAM flap applied for anterior neck resurfacing. Two cases with such anterior neck conditions are presented. © Wiley‐Liss, Inc.
Microsurgical repair of the parotid duct
Authors: Hallock Geoffrey G.
Published: March 2007

Because of its relatively small caliber lumen, traumatic injuries of the parotid duct appropriately lend themselves to microsurgical repair. With the evolution of more modern techniques and materials, inert nylon microsutures placed under magnification permit an ideal atraumatic anastomosis of the divided ends of the parotid duct. Such an exact approach may also obviate the need for long‐term stenting across the site of repair, which remains a controversial issue. © Wiley‐Liss, Inc.
Further investigation of secondary venous obstruction
Authors: Angel Michael F. , Knight Kenneth R. , Amiss L. R. , Morgan Raymond F.
Published: March 2007

The first ischemic insult a tissue suffers is primary (1°). A second ischemic episode, such as thrombosis after free tissue transfer may be regarded as secondary (2°) ischemia. The current study investigated 2° ischemia in rodent epigastric flaps. Flaps were elevated in 50 Sprague‐Dawley rats: group 1 had 5 hours 1° venous ischemia induced by placement of microvascular clamps; group 2 was like group 1, except venous continuity was re‐established by venous anastomosis after resection of the venous segment previously microclamped; group 3 had 15 minutes of 1° ischemia, 24 hr later 5 hr of 2° venous ischemia was induced by placement of microvascular clamps; group 4 was like group 3, except the venous segment was excised. Necrosis was evaluated on postoperative day 7. Both secondary ischemic groups had significantly less flap survival than the corresponding primary ischemic groups (P<0.001 for both). Resection of a portion of the vein and subsequent microanastomosis did not reduce flap survival (NS). Secondary venous ischemia of 5‐hr duration is poorly tolerated by rodent skin flaps. There was no difference in flap survival in those flaps whose veins were clamped for 5 hr compared to those flaps whose clamped venous segments were resected and re‐anastomosed. © Wiley‐Liss, Inc.
Carotid blood flow in anesthetized rats: Effects of carotid ligation and anastomosis
Authors: García‐Villalón Angel Luis , Roda José María , Alvarez Fernando , Gómez Bernardino , Diéguez Godofredo
Published: March 2007

An experimental model was developed for continuous measurement of the common carotid blood flow, in the anesthetized rat, with an electromagnetic flowmeter. The mean carotid blood flow for 41 rats averaged 3.2 ± 0.2 ml/min at an average mean arterial pressure of 101 ± 2.5 mm Hg and arterial pO2 of 106 ± 3.4 mm Hg, pCO2 of 38 ± 1.2 mm Hg, and pH of 7.36 ± 0.02. This model allowed short‐ and long‐term carotid hemodynamic changes to be recorded after contralateral carotid ligation or end‐to‐side carotid anastomosis. After ligation of the contralateral carotid, blood flow through the intact carotid increased 25% (at about 1 week) and 45% (at about 5‐6 months), whereas, after anastomosis, carotid blood flow increased 76% and 89% at periods comparable to those after ligation. Arterial pressure and gases did not change throughout the experimental periods. Probable mechanisms involved in these carotid hemodynamic changes are discussed. © Wiley‐Liss, Inc.
Endothelialization of microporous polytetrafluoroethylene grafts in the infrarenal aorta and caval vein of the rat
Authors: Zdanowski Zbigniew , Ribbe Else , Bengmark Stig
Published: March 2007

To study healing and endothelialization of vascular grafts, microporous polytetrafluoroethylene (PTFE) prostheses 2 mm in inner diameter and 5 mm long were implanted into the infrarenal aorta or caval vein of the rat. Patency was assessed in six rats from each group at days 3, 7, 14, 28, and 56 after implantation. Four grafts were occluded, two in the aorta (56 days) and two in the caval vein (3 and 14 days). The prostheses were examined via scanning electron and light microscopy for evaluation of endothelialization. At 3 days, the inner surface of the aortic grafts was covered by a plasma proteinaceous layer and that of the caval vein grafts by a thin mural thrombus. Endothelial cells then migrated from aorta/caval vein edges over the graft. At 14 days, the caval vein grafts were completely reendothelialized, and, at 28 days, the mural thrombus in these grafts was replaced by neointima. In contrast, endothelialization of the aortic grafts had advanced only 1 mm at about 56 days, never forming a complete endothelial layer. We conclude that endothelialization of microporous PTFE prostheses is more rapid and complete in the caval vein than in the aorta of the rat. © Wiley‐Liss, Inc.
Skeletal fixation in the rabbit knee transplantation model
Authors: Nolan Liana M. , Bowen C. Vaughan A. , Boyer Martin I.
Published: March 2007

The immature rabbit knee model for epiphyseal plate transplantations has been used by a number of investigators. Rigid fixation of the femoral osteosynthesis has been difficult to achieve reliably. This paper describes a new technique for obtaining consistent and satisfactory skeletal fixation in this model. The tibia was internally fixed with an ASIF/AO four‐hole minifragment plate. The femur was fixed with a 2.4 mm Steinman pin supplemented with two 26 gauge stainless steel interosseous wire loops placed at right angles to each other. © Wiley‐Liss, Inc.
Modified anastomotic technique for 1 millimeter internal diameter polytetrafluoroethylene arterial grafts in the rat
Authors: Golding Michael J. , Harris John P. , May James
Published: March 2007

Reported patency rates after standard end‐to‐end anastomoses for microvascular prosthetic grafts have been inconsistent and usually disappointing. A modified anastomotic technique is described in which the prosthetic graft is invaginated inside the arterial lumen. In this study of 6 cm lengths of 1 mm internal diameter polytetrafluoroethylene femoro‐femoral bypass grafts in the rat, 6 (40%) of 15 grafts with standard anastomoses were patent at 6 months compared to 28 (90%) of 31 grafts using the modified anastomotic technique (P<0.001). With invagination of the prosthetic graft inside the arterial lumen, reliable high patency rates can be achieved with microvascular prostheses long enough for potential clinical applications. © Wiley‐Liss, Inc.
Use of fibrin glue to minimize bleeding of microvascular repairs in hypertensive rats
Authors: Isogai Noritaka , Fukunishi Kenji , Kamiishi Hiroshi
Published: March 2007

The purpose of this study is to describe our technique of applying fibrin glue at the microvascular anastomotic site and to evaluate the effect of fibrin glue on anastomotic hemostasis and patency under various high pressure states using dopamine‐induced acute hypertension in rats. A total of 72 male Wistar Kyoto rats, 10 weeks old, were used in this study. Under urethane anesthesia, end‐to‐end anastomosis of the left femoral artery was performed using 10‐0 nylon suture by the standard interrupted suture technique. Pasteurized fibrin glue was then topically applied upon the suture line of the anastomosis. Thirty‐six normotensive rats were divided into three groups based on the number of sutures (4, 6, or 8) used to complete the anastomosis. Groups were subdivided, half receiving fibrin glue application and half without. Thirty‐six dopamine‐induced acutely hypertensive rats were divided into three groups based on the blood pressure levels of 150, 200, and 250 mmHg, respectively. These groups were again subdivided, with half receiving glue applications. Microvascular anastomosis was performed using 6 nylon sutures. Patency rates and anastomotic bleeding were evaluated. The results revealed that successful anastomoses could be performed with fewer sutures when fibrin glue was used as a reinforcement at the anastomosis. Fibrin glue was also effective at the maximum blood pressure (250 mmHg) with no anastomotic leakage and no decrease in postoperative patency rate. These results suggest that conventional microsurgical suturing technique combined with fibrin glue would be effective in the prevention of leakage in microsurgical repairs, even under conditions of high blood pressure. © Wiley‐Liss, Inc.
Variability of venous anatomy of rat testis: Application to experimental testicular surgery
Authors: Pascual Juan A. , Lemmi Carlos , Rajfer Jacob
Published: March 2007

The venous drainage of the testis of the laboratory rat was observed in 31 animals. The right testicular (internal spermatic) vein drained directly into the right common iliac vein in 77.4%, and into the inferior vena cava in 22.6% of the animals. The left testicular vein drained into the left common iliac vein in all animals, but in 90.3% there was also an accessory branch of the testicular vein draining into the left renal vein.

These observations suggest that in the rat the exact anatomy of the venous drainage of each testis should be identified prior to undertaking any surgical procedure on the testis where the venous vasculature plays a major role such as testicular transplantation or the creation of an experimental varicocele. © Wiley‐Liss, Inc.
Thigh adductor flap: An experimental model for free flap transfer in the rat
Authors: Koudsi Basem , Khouri Roger K.
Published: March 2007

A new model of rat muscle free flap transfer is presented. The flap is based on a long pedicle originating from the femoral vessels and continuing down to the distal saphenous margin at the ankle. The distal portion of the semitendinosus muscle is harvested along with the saphenous artery and great saphenous vein. A larger muscle flap may be harvested by including the distal portions of the posterior and anterior gracilis muscles. The flap can be transferred to remote sites on the animal, with a vascular pedicle of up to 3 cm in length. The diameters of the vessels repaired are of standard microsurgical size. This model has distinct advantages of simplicity, speed of dissection, high success rate after microvascular transfer, and versatility in placement of the muscle mass (due to the long pedicle). © Wiley‐Liss, Inc.
History of Microsurgery—from the beginning until the end of the 1970s
Authors: Tamai Susumu
Published: March 2007

Fine surgeries were started by vascular surgeons in the mid 1500s and included vascular ligature or suture of vascular wounds incurred in battle. Between 1800 and 1900, vascular end‐to‐end or end‐to‐side anastomoses and autogenous vein grafts became possible due to the efforts of Eck, Carrel and Guthrie. Thereafter, several experiments were performed for the transplantation of organs and limbs. Since the first use of the monocular microscope for ear surgery by Nylén in 1921 and the use of the binocular microscope by Holmgren in 1923, true microsurgery has developed and has gradually been specialized for every clinical discipline including otorhinolaryngology, ophthalmology, brain‐neurosurgery, orthopedic surgery, plastic surgery, transplantation surgery, oncology, gynecology and urology. This could not have been accomplished without the development of the Zeiss operating microscope (OpMi system), fine microinstruments, and fine suture materials. The author describes the history of microsurgery from its beginning through the end of the 1970s, covering as many surgical disciplines as possible. © 1993 Wiley‐Liss Inc.