Fixation of Various Porcine Arteries with an Epoxy Compound

Abstract: The clinical results of biological vascular grafts have been unsatisfactory. The poor results of these vascular grafts may be attributed to the fixatives, aldehydes, used in fixing tissues. In an attempt to overcome this problem, a new fixative, epoxy compound, has recently been used to fix biological vascular grafts. The study was undertaken to investigate the crosslinking characteristics, fixation index and denatur-ation temperature, of various porcine arteries fixed with an epoxy compound. The porcine arteries investigated in the study were the common carotid artery, internal thoracic artery, abdominal aorta, and saphenous artery. In addition, the effects of sonication on the porcine arteries before fixation on their cross-linking characteristics were analyzed. The fresh and glutaral-dehyde-fixed arteries were used as controls. It was noted that glycine, proljne, and alanine were the most abundant amino acids found in the porcine internal thoracic artery. In the amino acid analysis, it was observed that the amino acids in the porcine arteries reacted with epoxy compound or glutaraldehyde were lysine, hydroxylysine, histidine, and arginine. Of these amino acids, lysine was the most reactive. In general, the fixed arteries were relatively stiffer than their fresh counterparts. The fixation indices and denaturation temperatures of various porcine arteries were comparable throughout the entire fixation process. The amounts of free amino groups of the sonicated arteries were significantly lower than those of their unsonicated counterparts (p < 0.05). It is speculated that the diminishing free amino groups of the sonicated arteries may be attributed to the removal of the destroyed cell debris and adherent proteins of the arteries after sonication. However, it was learned that sonication on the porcine arteries before fixation did not seem to affect their fixation indices and denaturation temperatures. The results obtained in this study may help one in selecting the raw materials for developing a small-diameter biological vascular graft.     

A comparative study of long-term heart preservation using 12-h continuous coronary perfusion versus 1-h coronary perfusion following 11-h simple immersion

PURPOSE: We previously reported the superiority of the continuous coronary perfusion method using apparatus developed in our department. However, myocardial edema was a serious problem following this method. The purpose of this study was to attempt a comparative study of 12-h continuous perfusion and 1-h perfusion following 11-h simple immersion to evaluate the suitable method for long-term heart preservation. MATERIALS AND METHODS: HBD dogs were used in this study. After measuring baseline hemodynamics, cardiac arrest was attained and the coronary vascular beds were washed out with 4 degrees C Celsior solution. The grafts were divided into the two groups. In the CP group (n = 6), the grafts were preserved by continuous perfusion with 4 degrees C Celsior solution, and in the SI + CP (n = 6) group, the grafts were preserved with 11 h of simple immersion followed by an additional 1 h of perfusion with the same solution. The hemodynamics after orthotopic transplantation were compared. We also performed a histopathologic examination. RESULTS: Hemodynamics after reperfusion were maintained in both groups, and there were no significant differences in CO, Emax, or the rate pressure product between the two groups. In contrast, the percentage water content was significantly lower in the SI + CP group than in the CP group. Histopathologically, the myocytes were well preserved in both groups. However, ischemia-reperfusion changes were observed more frequently in the CP group than in the SI + CP group. CONCLUSION: A short-term perfusion following the simple immersion method may provide satisfactory results compared to the continuous perfusion method in long-term heart preservation.     

Pulmonary vascular abnormalities in experimentally induced congenital diaphragmatic hernia in rats.

In infants with congenital diaphragmatic hernia (CDH), abnormalities of the pulmonary arteries are present consisting of increased medial wall thickness and decreased external diameter. This forms the morphological substrate for persistent pulmonary hypertension, one of the leading causes of the high mortality in these patients. To elucidate the significance of these abnormalities, experimental models are required that mimic as close as possible the human situation. In our rat model we are able to study the hypoplastic CDH lungs extensively. In this study we performed a histological evaluation of the pulmonary arterial bed in the control group and the nitrofen-treated group in which the latter was divided into two subgroups, CDH and normal diaphragm. We examined the newborn rats after perfusion of the pulmonary arteries with barium gelatine and subsequent fixation. At the level of the respiratory bronchioles significant differences in the vessels were found consisting of decreased external diameter and increased wall thickness as percentage of the external thickness in CDH lungs compared with controls. Abnormal muscularization of the peripheral branches of the CDH pulmonary arteries was also found. We concluded that the rat model strongly resembles the human situation concerning the arterial bed in the lungs.     

不同灌注液对人离体小动脉保护作用的超微观察

目的 研究不同灌注液对离体小动脉超微结构的影响.方法 对手指近端毁损伤,缺乏再植条件或患者放弃再植的18指近节离断手指(热缺血时间＜2 h),分成3组,每组6指,分别在指动脉内灌注能量合剂(A组)、肝素钠+1%利多卡因(B组)和生理盐水(C组),4℃保存.分别于灌注后2、4 6 8、12、16、24 h切取指动脉3 mm,固定后切片电镜下观察小动脉在不同时间段超微结构的变化.另取离断指体近端未缺血的健康指动脉3 mm直接固定,为对照组.结果 电镜下观察:A组灌注8 h后,小动脉平滑肌细胞线粒体仅轻度肿胀,嵴变短.B组灌注4 h后,线粒体明显肿胀和内质网扩张;8 h后,血管平滑肌细胞内线粒体进一步肿大,嵴稀疏.C组灌注2 h后,内皮细胞轻度肿胀,少数脱落;4 h后,内皮细胞肿胀,部分脱落,血管平滑肌细胞内线粒体开始肿大;8 h后,血管平滑肌细胞内线粒体进一步肿大,部分出现空泡,嵴减少,基质变淡.与A组和C组比较,小动脉经肝素钠+利多卡因灌注后内皮细胞脱落延迟至16 h.结论 能量合剂灌注液对离体小动脉的超微结构有保护作用,能够减轻肢体缺血再灌注损伤的程度.     

Transplantation-Induced Functional/Morphological Changes in Rat Aorta Allografts Differ from Those in Arteries of Rat Kidney Allografts

The functional/morphological changes observed in rat aorta allografts were compared with those seen in the arteries of rat kidney allografts. Untreated allografts (F344-to-LEW) were collected at various times post-transplantation (Tx). Vascular smooth muscle cell (SMC) constriction to phenylephrine (Phe) and endothelial cell (EC)-dependent relaxation to acetylcholine (Ach) were assessed. Neointima formation in graft vessels was assessed by histology. In aorta allografts, the effects of Phe and Ach were irreversibly abolished within 3-2 weeks post-Tx. Neointima formation was consistently detected between 4 and 8 weeks post-Tx. In kidney allografts, sign of vasculopathy was seen in 10, 30 and 40% of resistance arteries at 8, 16 and 33 weeks post-Tx, respectively. In the main renal artery, substantial neointima formation was not apparent before 33 weeks post-Tx, the vasoconstrictor effect of Phe was fully maintained until then, and Ach-induced vasorelaxation was irreversibly reduced by approximately 70% from week 2 post-Tx onwards. These results indicate that the post-Tx functional/morphological changes seen in aorta allografts do not reflect those seen in arteries of kidney allografts. Hence, renal arteries from rat kidney allografts can be considered as a more relevant model to study the cascade of events leading to Tx-induced CGA in solid organ allografts.     

Total hip replacement induces injury to remote veins in a canine model

The effects of total hip replacement on the condition of the luminal surface of the jugular and femoral veins and the carotid and femoral arteries were studied in healthy dogs. Four hours after the completion of surgery, most of the blood was removed by whole-body perfusion and the vessels were partially fixed in situ by glutaraldehyde perfusion, harvested, and prepared for scanning electron microscopy. In control dogs (held under anesthesia) the luminal surfaces of the veins (including valves and confluences) and arteries were covered by intact endothelium and were free of adhering blood cells. The arteries from dogs that were operated on were also free of damage. In contrast, the veins from dogs that were operated on showed a series of roughly parallel microtears around 70 to 80 per cent of the confluences of the side branches with the jugular or femoral vein. The basement membrane as well as the endothelial sheet was torn, thereby exposing underlying connective-tissue fibers and smooth muscle cells. The endothelium separated along intercellular junctions. The tears were infiltrated with many leukocytes and platelets and some erythrocytes. Subtle endothelial changes and patchy leukocyte adhesion occurred away from the side branches. The mechanism or mechanisms remain to be elucidated.     

Perfusion pressure breakthrough threshold of cerebral autoregulation in the chronically ischemic brain: an experimental study in cats.

A study was designed to investigate hyperperfusion syndrome after the restoration of normal cerebral blood flow in a chronically cerebral ischemic state resulting from high-flow arteriovenous malformations or severe carotid stenosis. A fistula between the left distal common carotid artery and the jugular vein was created and the left vertebral artery was simultaneously occluded in 44 cats to produce a chronic cerebral ischemic state. For control experiments, 10 cats underwent occlusion of the left common carotid and vertebral arteries. Six weeks later, pial arterial behavior, disruption of the blood-brain barrier (BBB), and cerebral histological changes were investigated using three experimental methods. In the first, in which a fistula was occluded under normal conditions, pial arteries contracted to some 80% of the resting state; however, no BBB disruption or histological changes were observed. In the second experiment, in which a 20-minute occlusion of the left middle cerebral artery was performed in the cats with a patent fistula, a 30% to 40% dilated state of the pial arteries continued after recirculation, and BBB disruption-induced cerebral edema and infarction were observed. These findings were more prominent in the cats that underwent occlusion of the fistula. On the other hand, in the control group, the pial arteries returned to resting size within 40 minutes, and no BBB disruption or histological changes were observed. In the third experiment, in which moderate hypertension was induced for 1 hour, the pial arteries dilated much more remarkably; BBB disruption and cerebral edema were revealed to be more extensive in the cases of fistula occlusion than within those with a patent fistula. In the control group, however, the pial arteries contracted 10% during hypertension, while BBB disruption and histological changes were not evident. The results indicate that the perfusion pressure breakthrough threshold in the chronically ischemic brain may not be reduced by the restoration of normal blood flow, but may be decreased by the addition of new ischemic insults or hypertension.     

采用临时短节段椎弓根螺钉固定联合髂骨植骨治疗青少年腰椎椎弓崩裂症的临床观察

目的观察并评价临时短节段椎弓根螺钉固定联合髂骨植骨治疗青少年腰椎椎弓崩裂症的临床疗效。方法回顾性分析2016年8月至2018年12月因腰椎峡部崩裂症42例患者,对30例平均年龄为24.4岁符合标准的患者采取本手术方法。采用全椎弓根螺钉固定联合横连装置进行崩裂的峡部椎体和下位椎体进行坚强固定。对崩裂的峡部进行瘢痕清理和硬化骨处理;最后取自体髂骨进行峡部修补。术后定期随访,待峡部植骨融合后再次给予内固定取出,恢复固定节段活动度。行X线及CT检查,确定其峡部骨性愈合。待峡部融合后再次取出内固定装置,恢复固定节段活动,进行腰椎动力位片检查评估,测量固定节段的活动度,与术前同节段活动度进行对比。同时分别在手术前、手术固定1年时及内固定取出后1年行腰椎MRI检查,并采用modic分级及pfirrmann分级标准来观察固定节段椎间盘及椎体终板的变化,观察固定节段相应椎体的终板及椎间盘的变化。结果完整随访30例,平均随访时间24(18~36)个月;平均手术时间为107 min;平均出血量为126 ml;平均融合时间为13个月;融合率为100%。所有患者原有下腰痛症状消失,所有患者X线及CT片均提示峡部融合。内固定装置取出后,对患者进行腰椎过伸过屈位X线片检查,动力位片显示固定阶段活动度保存良好,活动度保留率为88.5%。腰椎MRI显示,16例患者固定阶段终板modic改变呈正变化,14例患者无变化,固定阶段椎间盘组织无明显退变变化。结论临时短节段椎弓根螺钉联合横连装置固定是一种治疗腰椎峡部裂简便、有效的方法,固定坚强、融合率高;且临时短节段坚强固定并不会加速固定节段椎间盘退变及临近节段的退变。     

Pathological study of rabbits＇ femoral arteries subjected to gunshot wounds combining with seawater immersion

To investigate pathological characteristics of gunshot wounds concomitant seawater immersion in rabbits‘ femoral arteries. Methods: Thirty rabbits were divided randomly into 3 groups: simple gunshot-wound group (Group Ⅰ, n = 10), gunshot wound with seawater immersion for 30 mins (Group Ⅱ, n = 10), and 60 mins group (Group Ⅲ, n =10). Femoral arteries were impacted by 0.38 g steel spheres fired with a 7.62 mm rifle. After being wounded, rabbits in Groups Ⅱ and Ⅲ were immersed in seawater for 30 or 60 mins, but those in Group I were not. At 2, 4, 6, 8, 12 hours following injury, a 40 mm segment of the artery on each side of the gunshot point were excised and observed by light and electron microscopy. Results : The potterns of arterial injuries were mainly contusion and transection. Completely transected artery was classified as primary-wound-tract area, contused area and shocked area. Compared with those in Group Ⅰ, the primary-wound-tract and contused areas in Group Ⅱ manifested obvious swelling in the arterial wall especially at the outside 2/3 of the media. Vacuolar structures were often seen in smooth muscle cells of the media. Intercellular space among the smooth muscle cells were filled with homogeneous acidophilic substances. Deep rugae among endothelial cells flattened or rugal folds lost their longitudinal orientation, and marked fibrin and platelet deposition were noticed. No significant difference was detected between Group Ⅱ and Ⅲ. The pathological changes in the shocked area were similar in 3 groups. Conclusions : For gunshot wounds concomitant seawater immersion in rabbits‘ femoral arteries, there was a marked swelling of cells and intercellular space in primary-wound-tract area and contusion area. The influence of these pathological changes on surgical reparation deservers further study.     

Edited by ZHAO BinPathological study of rabbits' femoral arteries subjected to gunshot wounds combining with seawater immersion

Objective: To investigate pathological characteristics of gunshot wounds concomitant seawater immersion in rabbits' femoral arteries. Methods: Thirty rabbits were divided randomly into 3 groups: simple gunshot-wound group (Group I, n=10), gunshot wound with seawater immersion for 30 mins (Group II, n=10), and 60 mins group (Group III, n=10). Femoral arteries were impacted by 0.38 g steel spheres fired with a 7.62 mm rifle. After being wounded, rabbits in Groups II and III were immersed in seawater for 30 or 60 mins, but those in Group I were not. At 2, 4, 6, 8, 12 hours following injury, a 40 mm segment of the artery on each side of the gunshot point were excised and observed by light and electron microscopy. Results: The patterns of arterial injuries were mainly contusion and transection. Completely transected artery was classified as primary-wound-tract area, contused area and shocked area. Compared with those in Group I, the primary-wound-tract and contused areas in Group II manifested obvious swelling in the arterial wall especially at the outside 2/3 of the media. Vacuolar structures were often seen in smooth muscle cells of the media. Intercellular space among the smooth muscle cells were filled with homogeneous acidophilic substances. Deep rugae among endothelial cells flattened or rugal folds lost their longitudinal orientation, and marked fibrin and platelet deposition were noticed. No significant difference was detected between Group II and III. The pathological changes in the shocked area were similar in 3 groups. Conclusions: For gunshot wounds concomitant seawater immersion in rabbits' femoral arteries, there was a marked swelling of cells and intercellular space in primary-wound-tract area and contusion area. The influence of these pathological changes on surgical reparation deservers further study.     

Pathological study of rabbits' femoral arteries subjected to gunshot wounds combining with seawater immersion

I tisestimatedthattheoccurrenceoffirearminjurytogreatarteriesofthelimbsaverages0.07% 2.4%ofallwarinjuries.1Theoccurrenceissimilarinseaorgroundwarfare.2Inseawarfare,thewoundisoftenimmersedintheseawater.3Ithasnotbeenreportedtoourknowledgeintheliteratureaboutthepathologicalchangesoffirearmwoundsconcomitantseawaterimmersioningreatarteriesanditsinfluence onsurgicalrepair.Inthisstudy,weusedrabbitsas theexperimentalmodelwhosefemoralarterywas subjectedtogunshotwoundandthenimmersedintothe seawatertoobs…     

Suprarenal fixation of endograft in abdominal aortic aneurysm treatment: focus on renal function

OBJECTIVE: The objective of this work was to evaluate any variation of renal function detected by renal scintigraphy after the suprarenal fixation of endografts for abdominal aortic aneurysm (AAA) repair. SUMMARY BACKGROUND DATA: In the few articles that have considered this problem, renal function was evaluated only by biochemical tests, which are inadequate in demonstrating small changes in renal function and in appreciating the worsening of a single kidney's function. METHODS: Between April 1999 and May 2002, 47 patients with an inappropriate infrarenal proximal neck had a suprarenal fixation for AAA. To assess renal function, a technetium-99m diethylene triamine penta-acetic acid (TC-DTPA) perfusion scintigraphy was performed preoperatively on the third postoperative day and at 6, 12 months, and then yearly thereafter. Worsening of renal function was defined as a decrease of glomerular filtration rate (GFR) > or =20% (detected with Gates method). Serum creatinine level was tested preoperatively and at the first and third postoperative day. RESULTS: Endograft deployment was technically successful in 44 patients (93.6%); clinical perioperative success was obtained in 46 patients (97.8%). In 12 patients (25.5%), a permanent reduction of the GFR was observed using postoperative TC-DTPA perfusion scintigraphy. By 99m TC-DTPA perfusion scintigraphy, a permanent reduction of GFR was observed postoperatively in 12 patients. A slight GFR reduction (<20%) was present in 7 (14.9%) patients, due to the planned occlusion of accessory renal arteries. A more significant GFR reduction (>20%) was present unexpectedly in 5 (10.6%) patients, in 3 of these a single kidney was involved, in 5 both with an increase of the serum creatinine level >20%. CONCLUSIONS: Suprarenal fixation of endografts in AAA treatment is a safe procedure with good early and midterm procedural results and a risk of GFR impairment (>20%) of 10.6%.     

Identification and selective perfusion of the spinal cord-feeding arteries by intrathecal pO2 monitoring for spinal cord protection.

OBJECTIVES: to study whether spinal cord-feeding arteries could be identified by the changes in the intrathecal pO2 (I-pO2), and to examine whether selective perfusion of feeding arteries identified by this method could protect the spinal cord against ischaemia. DESIGN: controlled animal experiments. MATERIALS AND METHODS: in experiment 1, using 16 mongrel dogs, 18 segmental arteries were cannulated through which oxygenated saline was injected and the I-pO2 change was observed. When the I-pO2 increase was more than 0.5 mmHg, the artery was considered to be a spinal cord-feeding artery. In experiment 2, involving 10 dogs, the segmental arteries identified as spinal cord-feeding arteries were perfused with arterial blood and the recovery of I-pO2 and evoked spinal potentials (ESP) was examined. RESULTS: of 208 segmental arteries examined, 176 (84.6%) arteries were correctly judged and 32 (15.4%) were not. It was observed that the I-pO2 recovered from 13.9 to 30.5 mmHg and the ESP recovered from 20.9% and 8.2% to 66.5% and 44.7% of each control for the first negative (N1) and second negative (N2) components, respectively. CONCLUSION: spinal cord-feeding arteries were successfully identified using the I-pO2 monitoring method. Perfusion of these arteries with arterial blood improved the I-pO2 and ESP, which were significantly depressed by ischaemia.     

Healing of a severe microarterial trauma: An experimental study

A severe microarterial trauma (arteriotomy/intimectomy) was introduced to the central arteries of rabbit ears. Twenty-one patent vessels, 3 at each interval of 2 hours, 1, 3, 7, 14, 30, and 90 days after reperfusion were taken for light and scanning electron microscopy studies. These vessels remained patent at all time intervals. A physiological “in vivo” perfusion technique with fixation fluid of normal temperature (37°C), pressure (120 mm Hg) and osmolarity (300 mOsm) was used to ensure fixed relaxed vessels. The endothelial, internal elastic, and part of the medial layers of vessel walls were removed following intimectomy. The inner surface of the intimectomy region was irregular and partly covered with thrombotic materials between 2 hours and 3 days postreperfusion. Endothelialization of the traumatized region was first observed at 3 days and was completed between 7 and 14 days. Intimal hyperplasia developed during this period and had not diminished in thickness by 30 or 90 days. The trauma and healing process of the arteriotomy/intimectomy are similar to the healing of vascular anastomoses and virtually identical to the clinical trauma of vessel avulsion, but neointima formation is more pronounced and engages vessel walls far outside the intimectomy site. © 1994 Wiley-Liss, Inc.     

In situ fixation of the spinal cord using microwave radiation

Due to its investiture with bone, the spinal cord can be difficult to study anatomically and histologically. Tissue degradation during immersion fixation or mechanical trauma during extraction of unfixed tissue often produces confusing artifacts. Perfusion fixation eliminates many of these problems, but it is a slow, tedious, and technically demanding procedure. This report demonstrates that microwave irradiation of the spinal cord before its removal from the spine is a rapid and easy method of tissue fixation with an absence of artifacts comparable to that with perfusion fixation.     

Feasibility of renal artery stenting before, during, and after endovascular aneurysm repair with suprarenal fixation endograft

Suprarenal fixation by means of proximal bare stent may help prevent endograft migration and proximal endoleak. It seems not to compromise renal perfusion and function; however, it is still unclear whether its presence is in conflict with stenting of the renal arteries to treat associated renal stenosis. We report five cases of renal artery stenting performed before, at the same time, or after endovascular treatment of abdominal aortic aneurysm with a suprarenal fixation endograft (Zenith; Cook, Biaverskov, Denmark). Suprarenal fixation endograft seems not to affect renal artery stenting regardless the timing of the procedure.     

供肝质量快速评价方法的探讨(附6例报告)

目的：探讨即时切取供肝质量的快速评价方法。方法：即时切取供肝前，取静脉血行全血细胞计数及肝功能检查；切肝时肉眼观察肝表面情况；取肝组织做快速石蜡切片检查；灌注时测定供肝的门静脉灌注压力和流量。结果：用上述四种方法对供肝质量进行综合评价，可疑质量不佳1例，植入后出现原发性无功能，评价供肝质量不佳1例未植入，其余4例供肝质量评价结果良好，供肝植入后近期肝功能良好。结论：供体血生化检查对评价供肝质量具有重要价值。肉眼观察直观、明了，对明显病变者可即刻放弃。对可疑肝组织形态有改变者快速石蜡切片检查能提供取舍证据。门静脉灌注压可间接反映供肝质量，对评价供肝质量更具否定意义。四种方法同时或选择性的应用可快速、准确评价供肝质量。     

海水浸泡开放性骨折不同救治方法的实验研究

目的观察两种骨折固定方法救治海水浸泡开放性骨折的大体形态、组织病理学、影像学变化。方法取成年新西兰兔50只，随机分为三组：对照组10只、A组20只、B组20只。于胫骨中段截骨制成开放性骨折动物模型。对照组伤口自然旷置3h，A组和B组海水浸泡伤口3h。随后对照组和A组行伤口清创、钢板螺钉内固定术；B组行伤口清创、外固定架固定、伤口开放换药、二期缝合。观察各组的伤口感染情况、骨折愈合的组织学、影像学变化和测定骨折断端骨痂的平均比灰度值。结果a）对照组感染1只（10％），A组感染15只（75％），B组感染5只（25％）。各组间结果有统计学差异（P〈0．05）。b）术岳45d时各组间骨折断端组织愈合等级有统计学差异（P〈0．05）。c）术后45d时各组间骨折部位骨痂的生长情况在影像学上表现为对照组大于B组大于A组。各组间骨愈合率对照组为100％，A组为66．7％，B组为93．3％。d）术后45d时骨折断端间骨痂的平均比灰度值对照组为8．1149±1．2043，A组为6．2268±1．4000，B组为6．5138±1．3045，各组间有统计学差异（P〈0．05）。结论海水浸泡使开放性骨折伤口感染率增高；海水浸泡使开放性骨折断端骨痂形成不良率增高；骨外固定架与钢板内固定比较救治成功率提高。     

Micro Perfusion and Quantitative Analysis of the Femoral Head Intraosseous Artery

The present study investigates the feasibility of micro perfusion of femoral head specimens from femoral neck fracture patients by the inferior retinacular arteries and performing intraosseous artery quantitative analysis of the femoral head. Twelve femoral neck fracture patients who had undergone conventional hip replacement surgery were included in this study. Femoral head specimen arteries were first dissected and exposed and then perfused by the inferior retinacular arteries and all the femoral heads underwent micro‐CT scanning. After micro‐CT scanning, a digital 3‐D model was reconstructed to quantify the femoral head intraosseous arteries for comparison with a normal femoral head. The artery length density, artery volume density, and artery length/volume ratio were calculated separately and compared with normal femoral head parameters. Micro‐CT scanning displayed the epiphyseal arterial network structure and their fine vascular branches in all 12 femoral neck fractures. Blood was supplied from the inferior retinacular artery to the epiphyseal arterial network then to all the fine blood vessels within the femoral head. No statistical differences were observed in femoral heads’ intraosseous artery length densities or volume densities between the normal and femoral neck fracture specimens, while the artery length/volume ratio showed a statistical difference, and the ratio increased from 19 to 46. Micro perfusion of the femoral head by the inferior retinacular arteries is possible and can present the epiphyseal network and their fine arterial branches in pathologic conditions to provide a morphological basis for the study of femoral head disease.     

Effect of suprarenal stent struts on the renal artery with ostial calcification observed on CT virtual intravascular endoscopy.

OBJECTIVES: The behaviour of stent struts crossing the renal ostia and their effect on renal ostia configuration is not well understood. The study aims to investigate whether suprarenal stent struts affect the morphological change of the renal artery with ostial calcification observed on CT virtual intravascular endoscopy. METHODS: Nine patients with abdominal aortic aneurysms undergoing suprarenal fixation of stent grafts were included in the study. All patients received a Zenith endovascular graft with uncovered suprarenal components placed above the renal arteries. Renal ostial calcification and configuration of stent wires crossing the renal ostium were characterized in each patient and maximal transverse and longitudinal diameters of the renal ostia were measured on virtual endoscopy pre- and post-stent grafting. RESULTS: There were altogether 17 renal ostia assessed with one patient having atrophic left kidney and no renal ostium being observed. Ostial calcification was found in five of the left renal ostia and five of the right renal ostia with one patient having bilateral ostial calcification. There was no significant difference between the renal ostial diameters measured pre- and post-stent grafting (p>0.05). Suprarenal stent struts were found to cross the renal ostia in various configurations observed on virtual endoscopy. All of the renal arteries were patent on follow-up CT scans after suprarenal fixation without stenosis or occlusion being observed. One patient with atrophic left renal artery developed renal failure following suprarenal stent grafting and received renal dialysis, while in the remaining cases median serum creatinine level did not change significantly. CONCLUSIONS: Suprarenal stent struts did not significantly affect the renal ostia with ostial calcification in terms of the diameter measurements and renal function. Further studies deserve to investigate the long-term effect of stent struts on the renal artery in terms of cross-sectional area reduction caused by stent wires and ostial calcification.