bluuebunny/crossref_metadata_2025_split huggingface dataset:
International survey of current microvascular practices in free tissue transfer and replantation surgery
Authors: Salemark Lars 
Published: March 2007

AbstractThe replies to a questionnaire about current microvascular practice circulated to microsurgeons worldwide are summarized and discussed. The material comprises results of 6,594 procedures performed during 1989. The survey topics dealt with include overall success rates in free flap transfer and replantation surgery, antithrombotic therapy, frequency of thrombosis, and frequency of reoperation. At centres not using antithrombotic therapy, the frequency of thrombosis in free flap procedures was higher than at centres using antithrombotic therapy, the result being a higher reoperation rate at the former. However, the final success rates for free flap transfers were about the same (95‐96%). The success rate for replantation with antithrombotic therapy was 92%; few centres attempted replantation without such treatment, and at these centres, the success rate was 82%, and reoperation was not attempted. The same modes of antithrombotic therapy and postoperative monitoring are used worldwide.
A new technique for microvascular sleeve anastomosis
Authors: Zhang Ling , Tuchler Robert E. , Shaw William W. , Siebert John W. 
Published: March 2007

AbstractThis study describes our experience using an improved technique for microsurgical sleeve anastomosis of arteries. Modifications of previously described techniques include utilization of a sidecut and placement of the two stitches within separate vertical planes. In 40 arteries, we attained a patency rate of 97.5%. Histology, in vivo observation, and flow study using high‐frequency pulsed ultrasound Doppler at 2 hr to 8 weeks demonstrate that the sidecut sleeve anastomosis shows patency and flow characteristics similar to those of standard end‐to‐end anastomosis, but with a dramatic decrease in operative time.
Vascularized autogenous canine coccygeal bone transfer
Authors: Yeh Lih‐Sen , Hou Sheng‐Mou , Lin An‐Chung 
Published: March 2007

AbstractBased on cadaver studies in dogs, the 8th, 9th, or 10th canine coccygeal vertebra with overlying skin was designed for free vascularized bone transfer. In six dogs the coccygeal osteocutaneous flap was transferred to fill a defect of the tibia, anastomosing the median caudal artery and one of the two caudal veins to the tibial vessels. The overlying skin provided a reliable monitoring system for the transferred tissue. The behavior of the vascularized coccygeal vertebrae was then evaluated with radiographic and histologic examination and compared with control vertebrae transferred without reconnection of the blood vessels. The results revealed that the canine coccygeal bone graft is a reliable vascularized osteocutaneous flap, which can be applied either in clinical veterinary surgery or in orthopedic microsurgical research.
Importance of fibrinolysis in limiting thrombus formation following severe microarterial trauma: An experimental study in the rabbit
Authors: Arnljots Bjõrn , Wieslander Jan B. , Dougan Peter , Salemark Lars 
Published: March 2007

AbstractIn a blind randomized study, two groups of six rabbits were treated with either the fibrinolytic inhibitor tranexamic acid, 14 mg/kg bw, or isotonic saline solution (control group) given intraaortically as single bolus injections 5 min prior to arteriotomy and intimectomy of central ear arteries. Arteriotomic bleeding times, accumulations of 32P‐labeled platelets, patency, and sizes of thrombus deposits 2 hr after reperfusion were recorded. Fixed vessels were observed by scanning electron microscopy. Bleeding times were similar in the two groups. The patency rate in the tranexamic acid group was 2/12, i.e., a significant reduction (P < 0.05) from 7/12 in the control group. Thrombus deposits in occluded vessels contained large amounts of fibrin and red cells. Platelet accumulations in occluded vessels were significantly lower in the tranexamic acid group than in the control group, which indicates that the ratio of fibrin to platelets was increased in thrombi formed during antifibrinolytic treatment. This study has demonstrated the importance of normal fibrinolytic capacity in limiting thrombus formation following microarterial trauma. It is suggested that the use of antifibrinolytic agents in microvascular surgery should be restricted.
Free muscle transplantation combined with intercostal nerve crossing for reconstruction of elbow flexion and wrist extension in brachial plexus injuries
Authors: Akasaka Yoshihisa , Hara Tetsuya , Takahashi Masataru 
Published: March 2007

AbstractComplete paralysis due to traumatic brachial plexus injury is extremely difficult to treat when the injury affects whole nerve roots and when motor function fails to show any signs of recovery. Seddon has suggested that arthrodesis of the shoulder and amputation at the humerus, combined with the use of a functional upper extremity prosthesis, was the most practical procedure available. Since 1965, in cases of irreparable lesions such as complete root avulsion type injuries, we have performed direct intercostal nerve crossing to the musculocutaneous nerve without free nerve graft to achieve elbow flexion. However, it is necessary to operate on the patient within 6 months following the injury to obtain good results. In the past there was no procedure for dealing with delayed cases of complete brachial plexus palsy. However, with the advent of microsurgical techniques, new approaches have become open to us. Since 1978, we have reconstructed the elbow flexor by the combined surgery of free muscle transplantation with intercostal nerve crossing in delayed cases of complete paralysis. This article introduces the operative technique and the results we have obtained.
Fiber type morphometry and capillary geometry in free, vascularized muscle transfers
Authors: Kuzon William M. , Rosenblatt J. David , Pynn Bruce R. , Plyley Michael J. , McKee Nancy H. 
Published: March 2007

AbstractIn order to establish the relationship among intraoperative ischemia time, the recovery of contractile function, muscle fiber morphometry, and capillary geometry following free muscle transfer, 15 male dogs underwent unilateral, orthotopic free transfer of the left gracilis muscle with microneurovascular anastomosis. Intraoperative ischemia time varied from 0 to 4 hours. After a recovery period averaging 14 months, isometric contractile function was measured in the transfers and the contralateral, control muscles. Muscle fiber type composition, fiber size, and capillary geometry were quantified from histochemical sections. Transferred and control muscles had similar type I fiber percentages, type I fiber sizes, and capillary densities. Type II fiber sizes were reduced in transfers relative to controls. There was no significant effect of intraoperative ischemia on any morphometric variable. Although contractile function was generally reduced after free, vascularized transfer, there was only a weak correlation between the recovery of tetanic tension and type I fiber percentage (r = 0.53, P < 0.05). It is concluded that free, vascularized muscle transfer results in minimal disturbance of muscle fiber type composition, fiber size, or capillary supply and that the diminished contractile function observed in this setting is still largely unexplained.
Histochemical staining of nerve endings as an aid to free muscle transplantation
Authors: Sanger James R. , Riley Danny A. , Yousif N. John , Matloub Hani S. , Bain James L. W. 
Published: March 2007

AbstractHistochemical staining techniques that identify intact motor nerve fascicles are available to aid free muscle transplantation. Cholinesterase activity of myelinated axons can be identified by Karnovsky and Roots's technique. Axon viability can be assessed based on the presence of axoplasmic enzyme activity. By reacting serial sections for Cholinesterase activity and carbonic anhydrase activity, which labels sensory axons, an accurate cross‐sectional map of regenerating or functional sensory and motor nerve fibers can be constructed. Resolving the motor and sensory identities of fascicles in a mixed peripheral nerve should lead to more precise coaptation of recipient motor fibers to the motor nerve of the transferred muscle and enhance reinnervation.
Multiorgan transplantation in the rat: Development of a new microsurgical model
Authors: Pirenne Jacques , D'Silva Milbhor , Nakhleh Raouf E. , Lee Sun , Dunn David L. 
Published: March 2007

AbstractAlthough transplantation of multiple abdominal viscera (MOTx) has been performed in humans, reproducible animal models and extensive laboratory work are needed to explore the physiological and immunological aspects of this new transplant procedure. We therefore developed a microsurgical model that allows en bloc transplantation of three major abdominal viscera. Using isogeneic rat strain combinations, 30% of the liver, pancreas, and duodenum and a segment of small bowel (SB) were heterotopically transplanted. A segment of aorta that included the celiac axis and the superior mesenteric artery provided the blood supply to the graft. Venous outflow occurred via the graft suprahepatic vena cava into the recipient's infrahepatic vena cava. The graft SB was anastomosed to the native SB. After a training period (N = 15), we could achieve a success rate of 83% (N = 23). Mean operation time was 105 minutes. Macroscopic and microscopic appearance of transplanted organs was normal. This study documents the feasibility of MOTx in the rat and provides a microsurgical model that should facilitate preclinical experimental research in this area.
Histomorphometric evaluation of intrahepatic changes following portal overflow in the rat
Authors: Benito Milagros , Del Pino Juan González , Hernández Lucia 
Published: March 2007

AbstractIntrahepatic changes after an end‐to‐side renoportal arteriovenous shunt were studied in 60 rats. Portal and vena caval pressures did not increase from 3 weeks to 1 year. The number and diameters of the portal and hepatic vein lumens were determined through morphometric evaluation to calculate the relative areas. The proportion of area composed by the portal veins increased 3 weeks after shunt creation (P < 0.001), reaching its highest level at 1 year (0.08% in control rats vs. 2.45% ± 0.1% at 1 year). The proportionate area for hepatic veins also increased after 3 weeks (P < 0.001), reaching its highest value by 12 weeks (0.49% in controls vs. 1.73% ± 0.08% at 12 weeks). Our results suggest that there was a dramatic drop in the intrahepatic vascular resistance, especially at the portal bed, which may have compensated for the portal overflow. The theories regarding forward overflow compensatory mechanisms are discussed.
Experimental study of neurotization of denervated muscles with nerve‐to‐vein transfer
Authors: Tada Hiroshi , Hirayama Takakazu , Atsuta Yuji , Takemitsu Yoshiharu 
Published: March 2007

AbstractNeurotization of denervated muscles was attempted by means of coaptation of peripheral nerves to the veins draining these muscles. In Sprague‐Dawley rats, the lateral gastrocnemius branch from the tibial nerve was severed and its proximal end was sutured to the distal stump of the lateral gastrocnemius vein. In all animals nerve‐muscle communication was confirmed electrophysiologically 2 and 6 months after the operation. However, histological examination revealed that the regenerated nerve fibers were not within the vessel lumen, but ran through the scar tissue in close proximity to the outside of the vessel, to enter the muscle. Control animals, in which only nerve resection was done, did not display nerve reinnervation. These results suggest that, although nerve fibers did not regenerate into the vein, the vein works well as va guide for regenerating nerve fibers to denervated muscle.
Morphologic and morphometric analyses of rat femoral arteries after crush injury
Authors: Chen Long‐En , Seaber Anthony V. , Glisson Richard R. , Mikat Eileen M. , Urbaniak James R. 
Published: March 2007

AbstractReplantation after crush amputation has a relatively low success rate. An arterial crush injury was produced in rats under a range of pressure (8.5 to 2,551 g/mm2) and durations (10 to 60 minutes). The degrees of vessel injury and thrombus formation were evaluated as functions of both crush force and duration, and the healing process was followed for 8 weeks. Crushing resulted in morphologic damage to the arterial wall but did not impair patency. Damage was directly proportional to crush pressure and duration. Intimal denudation caused flat platelet adhesion but no thrombus formation or thrombosis. Re‐endothelialization was completed by 2 weeks. Intimal hyperplasia appeared at 1 week and consisted of endothelia in the most luminal layers and smooth muscle in the deeper layers. The internal elastic lamina was intact in all specimens and was thought to minimize platelet aggregation on the arterial wall after denudation of the intima.
Geometrical approach to the end‐to‐side anastomosis
Authors: Werker Paul M. N. , Kon Moshe , Green Colin J. 
Published: March 2007

AbstractWe analyzed the procedure of performing an arterio‐ or venotomy in rats and changed it from parallel to the long axis to perpendicular to the long axis. Simultaneously, geometrical analysis of the shape of an arterio‐ or venotomy led to a new approach for the end‐to‐side anastomosis in experimental free flap transplantation. This new method was applied in 268 anastomoses. It necessitated only six sutures and resulted in 100% arterial early and late patency and in 99% venous early and late patency.
Histomorphometric study of experimental extramucosal ureteroureterostomy
Authors: Castejón Rafael , Gamallo Carlos , Jaureguizar Enrique 
Published: March 2007

AbstractThe reconstruction of the urinary tract is still nowadays a controversial issue. This study is based on the use of histomorphometric techniques to describe the changes which take place in extramucosal ureteroureterostomy. A medial laparotomy was performed in 41 Wistar rats. The left ureter was sectioned and an extramucosal anastomosis was performed. All rats were sacrificed 25 days postsurgery. Histomorphometric studies were performed on the sutured ureters as well as on the contralateral (unrepaired) ureters. Two of the 41 cases operated died. Five others developed hydronephrosis and/or urinary fistula. Histomorphometric studies gave an average cross‐sectional area of 98,662.5 ± 31,927 μ2 for the anastomosed ureters versus 75,176.3 ± 16,732.4 μ2 for the control ureters (P ⩽ 0.01). Sutured ureters showed an increase in the area of the muscular layer (P ⩽ 0.001) and the submucosa (P ⩽ 0.01) compared with control ureters. Mucosa and lumen areas showed no significant differences between the groups. Sectioned ureters show an increase in total area and width based on a hypertrophy of the muscular and submucosal layers.
Anastomotic failure due to acute vasculitis in free flap transfer: A case report
Authors: Sanger James R. , Kadz Bruce B. , Tieu Thu Minh , Matloub Hani S. , Yousif N. John 
Published: March 2007

AbstractWe report a case of anastomotic failure secondary to acute vasculitis in a free flap. Following transfer of a latissimus dorsi myocutaneous flap, massive hemorrhage from the anastomosis occurred six days postoperatively. This was associated with segmental infarctions of the areas of the flap, which was removed. Transmural necrosis of the thoracodorsal artery, secondary to acute vasculitis was demonstrated by histology. Subsequent biopsies revealed an autoimmune vasculitis.
New method for autogenous vein grafting with the telescoping anastomotic technique
Authors: Saitoh Satoru , Nakatsuchi Yukio , Hart W. Steve , Burkhalter William E. 
Published: March 2007

AbstractAn experimental study was performed to examine whether a microsurgical telescoping anastomotic technique could be applied twice in one vessel, for use in autogenous vein grafting. The rat inferior epigastric vein was grafted into a defect created in the femoral artery. The original telescoping method of Lauritzen was used, with two additional suture placements, to allow anastomosis at both proximal and distal sites. By placing the four sutures symmetrically and carefully timing the removal of the proximal and distal clamps, we achieved a patency rate of 77.3%. This is a new method for autogenous vein grafting that may serve as a prototype for an easier and possibly faster vein grafting technique. Our results appear to indicate that complete coaptation of the severed vessel ends is not necessarily required for patency in microvascular repair.
Long‐term histologic results of vein grafting with the telescoping anastomotic technique
Authors: Saitoh Satoru , Nakatsuchi Yukio , Kitagawa Eiji , Burkhalter William E. , Hart W. Steve 
Published: March 2007

AbstractWe studied the long‐term histologic results of a new method for autogenous vein grafting to examine whether stenosis at the anastomosis is maintained over time. Nineteen rat inferior epigastric veins were grafted into the femoral artery using a telescoping sleeve technique at both the proximal and the distal anastomoses. Specimens were studied macroscopically and histologically three months later. Stenosis at the anastomosis was located near the tip of the inserted vessel. The smallest inner diameters of the proximal and distal anastomoses were about 80% of the corresponding femoral artery diameter; no statistically significant difference was found between the two anastomoses. The grafts had a thickened wall due to intimal hypertrophy and fibrosis of the media. The inner diameter of the graft was, however, about twice that of the femoral artery, and these graft changes did not create any apparent constriction within the graft.
Dilatation in anastomosed arteries can be an artifact of explantation
Authors: Legrand Edmund K. , Stoloff David R. , Kirsch Wolff M. , Zhu Yong H. , Boukouvalas Zisis , Hardesty Robert 
Published: March 2007

AbstractFusiform dilation of the anastomotic site was found at explantation in the majority of rabbit femoral arteries anastomosed with newly developed micro‐clips. This observation was also noted at sutured anastomoses. The mechanism responsible for this morphologic finding was studied by the following experiments: (1) measuring and explanting anastomosed arteries relaxed with 20% lidocaine, (2) latex casts of microclipped arteries, (3) comparing angiographic and histologic morphometric data, and (4) examining synthetic vascular graft anastomoses with identical dilatation. The observations demonstrate that trauma associated with explantation (direct dissection and fixative perfusion) leads to arterial vasoconstriction, but focal medial damage at the anastomotic site prevents constriction at this site.
Histochemical discrimination of fibers in regenerating rat infraorbital nerve
Authors: Wilke Russell A. , Riley Danny A. , Sanger James R. 
Published: March 2007

AbstractIn rat dorsal root ganglia, histochemical staining of carbonic anhydrase (CA) and cholinesterase (CE) yields a reciprocal pattern of activity: Sensory processes are CA positive and CE negative, whereas motor processes are CA negative and CE positive. In rat infraorbital nerve (a sensory peripheral nerve), we saw extensive CA staining of nearly 100% of the myelinated axons. Although CE reactivity in myelinated axons was extremely rare, we did observe CE staining of unmyelinated autonomic fibers.Four weeks after transection of infraorbital nerves, CA‐stained longitudinal sections of the proximal stump demonstrated 3 distinct morphological zones. A fraction of the viable axons retained CA activity to within 2 mm of the distal extent of the stump, and the stain is capable of resolving growth sprouts being regenerated from these fibers. Staining of unmyelinated autonomic fibers in serial sections shows that CE activity was not retained as far distally as is the CA sensory staining.
Comparison of the influence of intralumenal irrigation solutions on free flap survival
Authors: Rumbolo Peter M. , Cooley Brian C. , Hanel Douglas P. , Gould John S. 
Published: March 2007

AbstractHeparin is commonly included in the irrigation solution used during microvascular surgery. Evidence has accumulated to indicate a beneficial effect of heparin on anastomotic patency, implying that its topical use is critical to success even in routine microvascular repairs. This investigation compared heparin and urokinase as additives to the irrigation solution (Ringer's lactate) used during rat groin free flap replantation. A newly trained microsurgeon performed all surgical procedures to lower the possible success rate through microsurgical inexperience and, thus, to create a stronger challenge for the topical irrigant. Solutions were administered on a blinded, randomized basis. Vessel patency and flap survival were followed for 7 days. No statistically significant differences were found between any of the treatment goups: patency and survival rates of 67% for heparin, 57% for urokinase, and 73% for controls (vehicle only). The flap failures that occurred may have been attributable to undetected technical errors due to the microsurgical inexperience of the surgeon. In a separate series, an experienced microsurgeon achieved 93% success using vehicle without additives for irrigation. These results suggest that topical heparin or urokinase is not essential for achieving high levels of success during microvascular surgery.
Restoration of venous outflow by simultaneous creation of an arteriovenous shunt and pedicle flap using a rat model of foot replantation
Authors: Zhou Zhao Yi , Rickard Thomas A. , Nichter Larry S. , Zemel Norman P. , Ashworth Charles R. , Kassabian Garo 
Published: March 2007

AbstractReplantation of amputated rat feet utilizing an efferent arteriovenous shunt constructed between the distal posterior tibial artery and the proximal posterior tibial vein, in the absence of all other venous drainage, provides an alternative pathway to the normal venous drainage in a replanted rat foot. However, this substitute venous drainage was insufficient to prevent progressive ischemia and necrosis of some or all of a replanted rat foot. When a cutaneous pedicle flap supplemented the arteriovenous shunt, venous drainage was much improved, tissue hypoxia and edema began to subside on the third day, severe tissue necrosis was prevented, and seven of eight feet replanted by this technique survived. These observations may be useful in replantation in humans when veins in the amputated part are too small to be used or so damaged that they cannot be repaired or reconstructed by a vein graft, but arteries can still provide a means of returning blood from the amputated part. Constructing an alternative pathway to the normal venous drainage pattern may allow severely damaged parts to survive after replantation.
Continuous local intraarterial infusion after prolonged arterial stasis in the fingers and toes
Authors: Fukui Akihiro , Maeda Masami , Mine Takako , Inada Yuji , Mizumoto Shigeru , Tamai Susumu 
Published: March 2007

AbstractSeven patients with trauma to eight digits and one toe went untreated for arterial stasis, with subsequent development of posttraumatic changes in skin coloration. In two patients involving two digits, a daily dose of 2,000 ml containing 240,000 U urokinase, 80 μg prostaglandin E1, and 10,000 U heparin in lactated Ringer's solution was administered by intravenous infusion for 10 consecutive days; one of the two digits became necrotic. In all subsequent patients, a daily dose of 80 ml containing 240,000 U urokinase, 40 μg prostaglandin E1, 10,000 U (maximum) heparin, and low‐molecular‐weight dextran was administered by continuous local intraarterial infusion for 10 consecutive days. These seven extremities survived, even in the case of two digits and one toe with over 50 hr of arterial stasis. We believe that revascularization of extremities following prolonged periods of arterial stasis may be possible by means of continuous local intraarterial infusion of antithrombotic agents. © Wiley‐Liss, Inc.