生物可降解输尿管支架在输尿管战创伤治疗中的降解特性

目的 建立一种新的输尿管战创伤动物模型,观察生物可降解输尿管支架在输尿管战创伤治疗中的降解特性.方法 使用自行研制的火器弹片伤制造模具,对模型建立组9条比格犬的随机一侧输尿管制造火器弹片伤后清创缝合,分别于术后40、80、120 d行静脉肾盂造影评估.再对阳性对照组9条比格犬的双侧输尿管均制造火器弹片伤,随机一侧放置聚乳酸可降解输尿管支架,另一侧放置双J管,分别于术后加、80、120d行静脉肾盂造影评估,支架行表面微观形貌及元素分析.结果 模型建立组9条比格犬,损伤侧术后出现肾积水,并逐渐加重.阳性对照组的9条比格犬,术后双侧均未见明显肾积水;可降解支架随时间推移逐渐降解,尤其术后80 d开始观察到降解速度明显加快;支架表面无钙沉积,而双J管表面可观察到明显钙沉积和结石形成,且随时间进展加重.结论 生物可降解支架在治疗输尿管火器弹片伤过程中,在起到了支撑、引流、预防肾积水作用后,随时间推移逐渐降解,并可避免结石形成.     

自体膀胱黏膜移植于浆肌层肠段重建输尿管的实验研究

目的长段输尿管狭窄或缺损的修复是泌尿外科棘手问题,将犬自体膀胱黏膜移植于浆肌层肠段重建输尿管,探讨其作为尿路替代材料重建输尿管的可行性。方法成年比格犬12条,体重6.5～9.3kg,雌雄不限,根据重建输尿管部位不同将其随机分成A、B、C组(n=4)。A组:自体膀胱黏膜移植于浆肌层肠段后包缝于人工输尿管支架制备人工输尿管,重建8cm长下段输尿管,将人工输尿管近端与上段输尿管断端吻合,远端与膀胱吻合。B组:同A组方法重建8cm长上段输尿管,将人工输尿管近端与肾盂吻合,远端与下段输尿管断端吻合。C组:同A组方法重建全段16cm长输尿管,将人工输尿管近端与肾盂吻合,远端与膀胱吻合。术前各组犬取血行肾功及电解质检测;术后观察犬的一般情况及支架管和造瘘管的引流、手术切口的愈合、并发症的发生等情况。术后第6周行生化指标复查及静脉尿路造影(intravenous urography,IVU)检查后,对人工输尿管行大体及组织学观察。结果B组1条犬术后2d因输尿管支架脱出,术后发生尿瘘及伤口感染,排除实验;其余犬术后均无并发症发生。术后第6周各组犬肾功和电解质检测与术前比较,差异均无统计学意义(P0.05)。IVU显示:A组1条犬术侧肾脏积水、上段输尿管扩张,B组1条犬人工输尿管与下段输尿管吻合口狭窄、同侧肾脏积水;其余各组犬术侧肾脏功能良好,人工输尿管有蠕动功能。组织病理学观察示术后第6周3组人工输尿管组织结构与正常输尿管相似,其中A、C组各1条犬出现人工输尿管炎症。结论自体膀胱黏膜移植于浆肌层肠段重建犬输尿管,可形成组织结构与正常输尿管相似的人工输尿管,且功能良好。     

游离输尿管移植段应用于输尿管重建的比格犬动物实验研究

目的:探究自体游离输尿管移植段应用于输尿管重建在比格犬动物实验模型中的安全性及可行性。方法:6只比格犬术前随机分成两组,两组分别随访至术后12周及28周行剖腹观察及留取标本,12周组额外接受静脉肾盂造影观察肾积水及输尿管通畅情况,标本石蜡包埋后行苏木精-伊红染色并观察吻合段输尿管组织学改变。结果:5只比格犬存活至观察终点且未出现明显的术后并发症,IVU提示术侧无或仅存轻度肾积水且未出现输尿管狭窄。组织学检查提示吻合口管腔开放,血管网重建存在。结论:自体游离输尿管移植段应用于输尿管重建在解剖和技术上是可行的,但仍需大样本量和长期随访支持。     

输尿管镜直视下球囊扩张治疗肾盂成形术后吻合口狭窄

目的 探讨输尿管镜直视下球囊扩张治疗肾盂成形术后吻合口狭窄的效果.方法 采用输尿管镜直视下球囊扩张治疗肾盂成形术后吻合口狭窄7例.男2例,女5例,平均33岁.均为腹腔镜肾盂离断成形术吻合口狭窄.结果 7例患者均扩张成功,直视下见狭窄段完全扩开,无严重并发症.术后2个月取出双J管,随访1年,复查B超、CT,肾孟积水明显减轻或消失,梗阻消除,腰痛等症状消失.结论 直视下输尿管镜球囊扩张对治疗肾盂成型术后并发的吻合口狭窄是一种安全有效的方法,创伤轻微,效果确切,并发症少,可作为肾盂成型术后吻合口狭窄的首选治疗方法.     

活体犬供肾腹腔镜切取-肾移植模型的建立

目的 探讨采用腹腔镜行犬活体供肾切取术并建立同种异体肾移植动物模型的可行性.方法 8只Beagle犬随机编号配对,供、受体犬左侧肾脏互换.采用腹腔镜行供肾切取术获取左侧肾脏,灌洗修剪完毕后将供肾动、静脉分别与受体髂外动、静脉行端侧吻合,供肾输尿管与受体膀胱行抗返流吻合,并置于实验犬左侧髂窝,同时切除受体右侧肾脏,术后口...     

腹腔镜肾盂成形术治疗输尿管连接处梗阻疗效观察

目的：评价腹腔镜肾盂成形术治疗肾盂输尿管连接处梗阻（UPJ0）的临床疗效及其可行性。方法：对50例UPJO均有不同程度肾盂积水患者分别使用Anderson—Hynes、FoleyY—V成形术、Fenger成形术及Hellstrom成形术进行治疗。结果：50例手术均获成功,无一例中转开放手术。手术时间2．5～4．5h,出血量35～88ml。40例术后随访6～24个月,IVP检查UPJ吻合口未见狭窄,肾盂输尿管排尿功能好,手术侧肾盂积水明显减轻或基本消失。结论：腹腔镜肾盂成形术具有术中创伤小、术后恢复快、疼痛减轻的优点,效果优于开放手术,是既安全又有效的微创手术方法。     

腹腔镜下肾盂成形术(附11例报告)

目的　介绍腹腔镜肾盂成形术新技术。　方法　对 11例诊断为肾盂输尿管连接部(UPJ)狭窄病人采用腹腔镜经后腹膜腔途径行肾盂成形术。　结果　 11例手术均获成功 ,手术时间2～ 4h ,出血量 4 0～ 90ml。术后 3～ 2 4个月B超复查 ,手术侧肾盂无积水。 6例术后 1年IVU检查UPJ吻合口未见狭窄 ,肾盂输尿管排尿功能好。　结论　腹腔镜肾盂成形术是治疗UPJ狭窄的有效微创手术方法之一     

漏斗形生物降解材料输尿管支架的动物实验研究

目的 设计漏斗形生物降解材料输尿管内支架，探讨该支架在上段输尿管梗阻治疗中应用的可行性。方法 制备己内酯丙交酯乙交酯三元共聚材料（PCLGA20：60：20），并加工成漏斗形支架管。雄性家犬4只，体重12～15kg，通过手术方法建立输尿管上段不完全梗阻动物模型；在此基础上行输尿管狭窄段切除吻合术，术中留置漏斗形PCLGA支架管支撑引流；术后定期行IVU检查，并于术后12周行术侧输尿管组织病理学分析。结果 4只犬成功建立输尿管上段梗阻动物模型。漏斗形PCLGA支架管内引流效果良好，肾盂及输尿管扩张积水逐渐缓解；6～8周支架管密度减低，陆续发生断裂，断裂的支架管并未造成输尿管梗阻；术后12周支架管完全降解并排出体外，吻合段输尿管无狭窄，造影剂通过顺畅，局部组织病理学改变轻微，仅见移行上皮细胞增生和固有层增厚。结论 漏斗形PCLGA支架管生物相容性良好，降解时间适宜，在上段输尿管手术中具有良好的内引流效果。     

双支肾静脉间输尿管所致狭窄行后腹腔镜下肾盂离断成形术一例报告并文献复习

目的 探讨后腹腔镜手术治疗双支肾静脉间输尿管所致UPJ狭窄的可行性及效果.方法 患者为男性,28岁.左腰部酸痛6个月,于外院诊断为左侧UPJ狭窄、左肾积水,留置左输尿管支架管3个月后拔除.B超检查示左肾积水、左侧UPJ狭窄,CT示左侧UPJ狭窄,狭窄处与左肾静脉关系密切,且走行于双支肾静脉之间.肾图示双肾功能受损,左肾GFR 35 ml/min,右肾GFR34 ml/min,左肾积水,左侧上尿路机械性梗阻.全麻下行后腹腔镜下左肾盂离断成形术. 结果 手术顺利,术中发现左肾静脉为双支,左肾盂输尿管在肾静脉间穿行,位于腹侧的一支肾静脉主干压迫左UPJ,同时存在肾迷走动脉与输尿管伴行入肾.术中切除狭窄段约0.5 cm后将输尿管绕行至腹侧肾静脉分支前方,将肾盂成形后与输尿管吻合,同时留置输尿管支架管.手术时间240 min,出血量50 ml,术后住院4d,无发热、术后大出血等并发症.术后随访4个月,复查B超示肾积水明显减轻.结论 双支肾静脉间输尿管所致UPJ狭窄临床罕见,可行后腹腔镜下肾盂离断成形术,创伤小,短期随访效果满意.     

离断性肾盂成形术双J管内引流治疗肾盂输尿管连接部狭窄

目的：探讨离断性肾盂成形术双Ｊ管内引流治疗肾盂输尿管连接部狭窄的临床疗效。方法：采用离断性肾成形术治疗先天性肾盂输尿管连接部狭窄３２例共３５侧,常规采用双Ｊ管作支架内引流,术后１个月拔除双Ｊ管,３个月行静脉肾盂造影复查。结果：患者积水好转,吻合口通畅,尿常规检查无严重尿路感染。     

Introduction to biodegradable polylactic acid ureteral stent application for treatment of ureteral war injury

Study Type – Therapy (case series) Level of Evidence 4

OBJECTIVE

? To study the operability and effectiveness of a biodegradable ureteral stent for clinical treatment of ureteral war injury using a canine model.

MATERIALS AND METHODS

? A device was designed and employed to generate firearm fragment wounds in unilateral ureters (on randomly chosen sides) of nine beagles (Group A). The wounded ureters were then debrided and sutured. ? Intravenous pyelography (IVP) and radioactive renography were performed 40, 80 and 120 days postoperatively. In Group B, firearm fragment wounds were made to the bilateral ureters in nine beagles. A polylactic acid stent was placed unilaterally (on a randomly chosen side) whereas the ureter on the other side was debrided and sutured without stenting. ? Both IVP and radioactive renography were performed 40, 80 and 120 days postoperatively. The operability and effectiveness of the biodegradable ureteral stent were studied thereafter.

RESULTS

? In Group A, hydronephrosis and hydroureter occurred and worsened postoperatively on the wounded sides in all nine beagles. The ratio of the renal partial concentration indices (RPCI) between the kidneys (unwounded side : wounded side) increased. ? The ratio of the kidney washout half‐time between the kidneys (unwounded side : wounded side) decreased. In Group B, neither hydronephrosis nor hydroureter was found postoperatively in the stented ureters but both occurred in the unstented ureters in all nine beagles. ? The ratio of RPCI between kidneys (stented side : unstented side) increased whereas the kidney washout half‐time ratio between the stented and unstented sides decreased. Differences were significant.

CONCLUSION

? In Group A, the new canine model for firearm fragment wounds was tested and proved to be operable and effective. In Group B, hydronephrosis and hydroureter were effectively prevented in ureters by biodegradable stent placement compared with the non‐stented ureters where hydronephrosis and hydroureter occurred. The renal concentration capacity was effectively protected and the half‐time of kidney washout was shortened.     

The effect of new monofilament absorbable sutures on the healing of musculoaponeurotic incisions, gastrotomies, and colonic anastomoses

The purpose of this study was to quantitate the effect of two new synthetic monofilament absorbable sutures, Maxon and PDS, on the healing of musculoaponeurotic incisions, gastrotomies, and colonic anastomoses. Wound healing was assessed by measuring the resistance of the closed wound to leak or burst with controlled infusion of fluid. Bursting strength measurements of these incisions were compared with those undertaken in age-weight matched controls without wounds to determine the rate of gain of wound strength. The bursting strength measurements of unwounded tissue was found to vary according to the age, weight, and specific tissue. As the animals gained weight over 42 days, the bursting strength of their colons and musculoaponeurotic tissues significantly increased. In general, the regain of prewounding bursting strength was inversely proportional to the bursting strength of the unwounded tissue. The bursting strength of abdominal musculoaponeurotic tissue was the highest, followed by the stomach and then the colon. The time intervals in which the wounded musculoaponeurotic tissues, gastrotomies, and colonic anastomoses regained the strength of the unwounded tissue was 42, 14, and 7 days, respectively. The performance of Maxon and PDS sutures in the musculoaponeurotic tissues, gastrotomies, and colonic anastomoses was similar.     

Ultrastructural changes of the cochlea after oral and maxillofacial firearm wounds

BACKGROUND: There have been reports that maxillofacial firearm wounds could induce hearing loss. The effects on the ultrastructure of the cochlea and cochlear nerves after oral and maxillofacial firearm wounds are still unclear. This experiment investigates the ultrastructural changes of the cochlea and cochlear nerve after oral and maxillofacial firearm wounds. METHODS: Twenty dogs were wounded by steel spheres or detonators to establish animal models of oral and maxillofacial firearms wound. At different times after trauma, the wounds were examined and the specimens of the cochlea and cochlear nerve were taken to study the ultrastructural changes. RESULTS: The ultrastructural changes of the cochlea and cochlear nerve at 1 hour after trauma were cilia disorganization, edema of the nerve, and mitochondrial denaturalization. At 6 hours, there was extensive degeneration in the cochlea and cochlear nerve, cilia falling off of hair cells, and dissolution of the nerve sheath structure. CONCLUSIONS: The ultrastructure of the cochlea and cochlear nerve after injury is severe, but in the early period the injury is reversible.     

Collagen biosynthesis in healing wounds of the spinal cord and surrounding membranes

Kinetics of collagen synthesis and deposition were studied in the canine spinal cord, pia mater, and dura mater and in wounds of these tissues over the first 8 weeks. Little collagen is present in unwounded spinal cord compared with surrounding mesenchymal membranes. Collagen synthetic potential was found within the spinal cord, a tissue of neurectodermal origin. Rate of collagen synthesis per collagen content in the unwounded spinal cord was high. This synthetic rate was as high as that of wounds at their maximum collagen synthetic rates. Substantial deposition of collagen followed spinal cord wounding. Wounding the spinal cord, pia mater, and dura mater caused substantial elevations in rates of collagen synthesis in each tissue. These synthetic rates remained at maximum levels throughout the 8-week study, a prolonged period when compared with other wounded tissues previously studied. The role of mesenchymal tissue physiology in central nervous system wound healing is discussed. The potential value of these findings for further studies and for experimental manipulation of the healing process in spinal cord and central nervous system wounds is presented. Implications of these findings on the hypothetical relationship of scar to spinal cord and central nervous system regeneration are noted.     

Experimental studies with absorbable and nonabsorbable sutures in infected canine arterial anastomoses

Vascular anastomoses are usually performed with nonabsorbable synthetic suture material. In an infected wound suture material may have a negative effect on the healing of vascular anastomoses, leading to leakage and formation of false aneurysms. In a canine model 40 neck wounds and 40 groin wounds were contaminated with a standard suspension of Staphylococcus aureus. Subsequently 80 end-to-end anastomoses were performed in both carotid and femoral arteries with the absorbable polydioxanone (PDS) or the nonabsorbable polypropylene (PPL) suture material in one of either side. After wound infection or hemorrhage occurred, or at least 7 days to 6 months after vascular surgery, the dogs were put to death and the contaminated vessels were removed to determine the extent of infection with light and scanning electron microscopy. Macroscopic (presence of pus, anastomotic rupture, or aneurysm) and microscopic findings (absorption, tissue reaction) were compared statistically with the McNemar test. There was no difference in the incidence of wound infection between the sutures examined. Bacteriologic cultures revealed no other microorganism than the inoculated staphylococcus strain or occasional skin contaminants. In the PPL group hemorrhages occurred more frequently (n = 6) than in the PDS group (n = 2; p = 0.125). Anastomotic aneurysms (n = 5) were found only in the PPL group (p = 0.375). These differences, although statistically not significant (because of the small number of the studied anastomoses), suggest the use of monofilament absorbable suture material for autogenous anastomoses in a contaminated area.     

New bioabsorbable polylactide ureteral stent in the treatment of ureteral lesions: an experimental study

OBJECTIVE: To evaluate the suitability of a new biodegradable double-helical spiral self-reinforced poly-L,D-lactide copolymer (SR-PLA 96; L/D ratio 96/4) stent as a device for ureteral stenting in respect to changes in kidney function during the biodegradation process. MATERIALS AND METHODS: Sixteen dogs were used as experimental animals and were subdivided into two groups of eight. In Group A, both ureters were cut transversally, sutured, and stented. The right ureter was stented using an SR-PLA 96 stent, whereas a double-J C-Flex stent was used on the left side. Cystotomy was performed at 6 weeks to remove the double-J stents. In Group B, the right ureter of each dog was cut and stented in similar manner using an SR-PLA 96 stent, whereas the left ureters served as untreated controls, and cystotomy was not performed. Serum creatinine and nitrogen values were measured, urine was analyzed for signs of infection, and renal function was evaluated by urography and renography examinations preoperatively and at 6, 12, and 24 weeks postoperatively, at which time points, the dogs were euthanized and the ureters dissected to find persistent SR-PLA 96 particles and macroscopic local changes. There were no urinary tract infections found during the study. RESULTS: In the SR-PLA 96-stented ureters, obstructive hydronephrosis and stricture formation were observed in two cases (11%), with distal displacement of the SR-PLA 96 stent in another case (5.5%). In two additional renal units, a temporary prolongation in the kidney washout time was observed at 6-week renogram examinations. In the C-Flex-stented ureters, temporary changes in renography studies were observed in three cases (37.5%) at 6 weeks. Kidney washout times were protracted at 6 weeks in the pigtail-stented ureters in Group A as a sign of a pressure rise in the renal pelvis secondary to the direct connection between the renal pelvis and bladder, whereas pressure remained normal in SR-PLA 96-stented ureters. In Group B, renal function remained normal after ureteral repair in SR-PLA 96-stented ureters compared with the controls. CONCLUSIONS: The double-helical apical stent design offers some advantages over a double-J design. The risk of pressure-induced kidney damage is lowered, because there is no direct connection between the bladder and renal pelvis, and the risk of upper urinary tract infections is reduced. The biodegradation of the device necessitates the removal of the stent. These preliminary results suggest that a biodegradable SR-PLA 96 stent with more effective expansion capacity can be used for stenting after a ureteral repair.     

Recovery process of injured ureters in dogs

This paper is the 13th report in a series of studies on the application of microexplosion to medicine and biology. The recovery process of injured ureters was investigated in the day. The 60 ureters of 42 mongrel dogs were used. The ureter was injured with a nail, punch or surgical knife. The "pierced injury" was passed through the ureter with a nail of 1 mm or 2 mm in diameter, the "punch injury" was punched out in the ureter by a puncher of 1 mm or 2 mm in diameter and the "cut injury" was cut in the ureter 5 mm or 10 mm in size with a surgical knife. The recovery process of the injured ureter was observed in each of the two ureters 3 days, 1 week, 3 weeks, 6 weeks and 12 weeks after the injury by means of IVP, for macroscopic and microscopic findings. The results were as follows: 1) In IVP, it was observed that the 1 mm pierced injury resulted in no urine leakage after 3 days, that the 2 mm pierced injury and 1 mm punch injury in no urine leakage after almost 1 week and that the 2 mm punch injury and 5 mm cut injury and 10 mm cut injury in no urine leakage after almost 3 weeks. Hydroureter due to tissue edema was observed only in one ureter with a 10 mm cut injury after 1 week. No ureteral stricture, hydronephrosis or hydroureter was observed in the other ureters.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bilateral hydronephrosis secondary to ileocolic Crohn's disease

Unilateral hydronephrosis can complicate a far from negligible number of patients with Crohn's disease. Bilateral hydronephrosis associated with Crohn's disease is a much more unusual entity. In the other hand, the treatment for this condition is still controversial. We present the case of a 44 year old female with several bowel obstruction episodes caused by ileocolic Crohn's disease. During the last episode she was also diagnosed of bilateral hydroureter and hydronephrosis. After the resolution of the bowel obstruction and the placement of a double J catheter in both ureters, the patient was operated. Ileocolic resection and bilateral ureterolysis with omental wrapping were performed. Although urinary and wound infection complicated the postoperative course, and a enterocutaneous fistula had to be medically treated one year later, the patient is now free of symptoms and her renal function is normal.     

A comparison between cyclosporin A and methylprednisolone plus azathioprine on bronchial healing following canine lung autotransplantation

The effects of two low-dose immunosuppressive therapies upon the healing of the bronchial anastomosis and skin wounds following lung autotransplantation were evaluated. Autotransplantation was performed in three groups of dogs: Group 1 (nine dogs) received no immunosuppression, Group 2 (seven dogs) received postoperative immunosuppression with methylprednisolone (2 mg/kg) and azathioprine (1.5 mg/kg), and Group 3 (four dogs) received postoperative immunosuppression with cyclosporin A (20 mg/kg/day). Skin incisions 7 cm in length were made in the dorsal region of each dog. Dogs were put to death 23 days postoperatively, and the breaking strength of the bronchial anastomoses and skin wounds was evaluated with the Instron Universal Testing Machine, with a cross-head speed of 0.5 cm/min. Bronchial breaking strengths were similar in Groups 1 and 3 and significantly higher than in Group 2 (p less than 0.001). Skin breaking strengths were similar in Groups 1 and 3 and significantly higher than in Group 2 (p less than 0.001). Scanning electron microscopic (SEM) studies of both skin and bronchial wounds showed normal formation of collagen bundles in Groups 1 and 3 but a disorganized pattern in Group 2. Our results suggest that low-dose immunosuppression with methylprednisolone and azathioprine significantly affects wound healing and breaking strength of both bronchial anastomoses and healed skin incisions following canine lung autotransplantation. Immunosuppression with cyclosporin A had no adverse effect on either bronchial or skin healing.