PURPOSE: An ideal suturing material should be strong, easy to handle, should produce minimal tissue reaction and finally should disappear without a trace. Various micro-vascular suture materials have been produced in the past several decades in order to meet these demands. We have used nylon suturing material in experimental microsurgery because it is less expensive than polypropylene. After carotid artery end-to-end anstomosis, we found fusiform aneurysm incidentally. In this study 9-0 nylon (group I) and 9-0 polypropylene (group II) were compared to 10-0 nylon (group III), and 10-0 polypropylene (group IV) in order to survey the incidence of aneurysmal development in each material for use in microvascular surgery. METHOD: Forty Sprague-Dawley rats, 230 g to 350 g body weight, were used for this study. The carotid arteries were anastomosed end-to-end with 9-0 nylon, and 10-0 nylon, in addition to 9-0 polypropylene, and 10-0 polypropylene. The suture number of all arteries was 10 points except for two cases were 11 points due to uncontrolled bleeding. Specimens were harvested 1 week, 3 weeks, 6weeks and 10 weeks postoperatively. RESULT: The number of animals studied during the first week totaled 20 carotid arteries and they showed no interval change. After 3 weeks, we identified aneurysms in following cases: group I 3 cases, group II 2 cases, group III 1 case and group IV 1 case per five cases in each group. After 6 weeks, gross aneurysmal changes seen: group I, all (5) cases; Group II, 2 cases; group III, all (5) cases; Group IV, 3 cases. After 10 weeks, many aneurysms were observed: group I, all (5) cases; group II, all (5) cases; group III, 0 case; group IV, 2 cases. The aneurysms were measured and ranged in size from 1.3 mm to 8.1 mm. Histological analysis for inflammation, fibrosis and medial necrosis at the anastomosis site revealed no significant difference between same sized suture materials. If the experimental aneurysms were more than 5 times the diameter of the carotid artery, the aneurysms were considered to be experimental giant aneurysms. Seventy of our 34 experimental aneurysms were considered to be giant aneurysms. CONCLUSION: Our findings demonstrate that the development of aneurysms was related to size of the suture material and not the type of suturing material used. An ideal suture material for anastomosisof the carotid artery in the rat wasd a 10-0 monofilament suture material with suture numbers was above 10 points. We also made good aneurysm model. When we used 9-0 suture material and suture numbers were below 10 points multiple aneurysms developed. This model demonstrated the development mechanism of giant fusiform aneurysms.
Aneurysm* ; Animals ; Arteries ; Body Weight ; Carotid Arteries ; Carotid Artery, Common* ; Fibrosis ; Hemorrhage ; Incidence ; Inflammation ; Microsurgery ; Necrosis ; Nylons ; Polypropylenes ; Rats* ; Rats, Sprague-Dawley ; Sutures

PURPOSE: An ideal suturing material should be strong, easy to handle, should produce minimal tissue reaction and finally should disappear without a trace. Various micro-vascular suture materials have been produced in the past several decades in order to meet these demands. We have used nylon suturing material in experimental microsurgery because it is less expensive than polypropylene. After carotid artery end-to-end anstomosis, we found fusiform aneurysm incidentally. In this study 9-0 nylon (group I) and 9-0 polypropylene (group II) were compared to 10-0 nylon (group III), and 10-0 polypropylene (group IV) in order to survey the incidence of aneurysmal development in each material for use in microvascular surgery. METHOD: Forty Sprague-Dawley rats, 230 g to 350 g body weight, were used for this study. The carotid arteries were anastomosed end-to-end with 9-0 nylon, and 10-0 nylon, in addition to 9-0 polypropylene, and 10-0 polypropylene. The suture number of all arteries was 10 points except for two cases were 11 points due to uncontrolled bleeding. Specimens were harvested 1 week, 3 weeks, 6weeks and 10 weeks postoperatively. RESULT: The number of animals studied during the first week totaled 20 carotid arteries and they showed no interval change. After 3 weeks, we identified aneurysms in following cases: group I 3 cases, group II 2 cases, group III 1 case and group IV 1 case per five cases in each group. After 6 weeks, gross aneurysmal changes seen: group I, all (5) cases; Group II, 2 cases; group III, all (5) cases; Group IV, 3 cases. After 10 weeks, many aneurysms were observed: group I, all (5) cases; group II, all (5) cases; group III, 0 case; group IV, 2 cases. The aneurysms were measured and ranged in size from 1.3 mm to 8.1 mm. Histological analysis for inflammation, fibrosis and medial necrosis at the anastomosis site revealed no significant difference between same sized suture materials. If the experimental aneurysms were more than 5 times the diameter of the carotid artery, the aneurysms were considered to be experimental giant aneurysms. Seventy of our 34 experimental aneurysms were considered to be giant aneurysms. CONCLUSION: Our findings demonstrate that the development of aneurysms was related to size of the suture material and not the type of suturing material used. An ideal suture material for anastomosisof the carotid artery in the rat wasd a 10-0 monofilament suture material with suture numbers was above 10 points. We also made good aneurysm model. When we used 9-0 suture material and suture numbers were below 10 points multiple aneurysms developed. This model demonstrated the development mechanism of giant fusiform aneurysms.
Aneurysm* ; Animals ; Arteries ; Body Weight ; Carotid Arteries ; Carotid Artery, Common* ; Fibrosis ; Hemorrhage ; Incidence ; Inflammation ; Microsurgery ; Necrosis ; Nylons ; Polypropylenes ; Rats* ; Rats, Sprague-Dawley ; Sutures

PURPOSE: The presence of C4d in peritubular capillaries (C4d (PTC)) as a diagnostic in-situ marker of acute humoral rejection and CD20 as marker of B-cell deposition in graft kidney has been reported to be related to steroid resistance and poor outcome. In this retrospective study, we evaluated the clinical significance of C4d and CD20 in allograft renal biopsies by immunohistochemistry technique. And we also evaluated the relationships between C4d and CD20 positive B lymphocytes. METHODS: We studied 22 patients who had been biopsied for suspected acute rejection. Biopsies were classified by updated Banff 97 criteria. Of the 22 cases, borderline rejection and Banff 1A were 11 cases respectively and no case had a vascular lesion. Paraffin sections were stained with monoclonal antibodies (anti-C4d and -CD20) using an immunohistochemistry technique and the results of immunohistochemistry were analyzed by clinical data. RESULTS: Of the 22 cases, 22.7% (5/22) showed diffuse and 40.9% (9/22) showed focal C4d positivity in peritubular capillaries. The grafts failed to survive in 20% (1/5) of the diffuse (P), 44.4% (4/9) of the focal, and 0% (0/8) of the negative group for 2 years since postbiopsies, however, the C4d staining was not statistically related to graft loss and graft survival rates (P=0.091, P=0.106 respectively). The C4d positivity was significantly related to the level of serum creatinine (P=0.042) and to steroid pulsing therapy resistance (P=0.030). However C4d deposition was not associated with recipient gender, age, type of donor (living vs deceased), HLA matching, induction, and Banff classification. On the CD20 immunostaining, 50.0% (11/22) showed negative reactivity, 9.1% (2/22) one nodule, 40.9% (9/22) 2 nodules. The presence and the number of CD20 positive nodules were not correlated to the C4d clinical data. But, the degree of C4d staining was statistically related with the presence of CD20 positive nodules (P=0.029). CONCLUSION: The peritubular capillary C4d is clinically important however, not likely a significant predictor of grafts survival rates in mild rejection. The clinical implication of CD20 positive B lymphocyte nodules in acute rejection was not demonstrated in this study. But, CD20 positive B lymphocyte may be a positive linkage with C4d and participate in humoral rejection.
Antibodies, Monoclonal ; B-Lymphocytes ; Biopsy ; Capillaries ; Creatinine ; Graft Survival ; Humans ; Immunohistochemistry ; Kidney ; Lymphocytes ; Paraffin ; Rejection (Psychology) ; Retrospective Studies ; Survival Rate ; Tissue Donors ; Transplantation, Homologous ; Transplants