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911.
Mats Sjöström DDS PhD Lars Sennerby DDS PhD Stefan Lundgren DDS PhD 《Clinical implant dentistry and related research》2013,15(3):367-379
Purpose: Evaluate correlations between volume change for iliac crest bone grafts in maxillary reconstruction (graft volume change [GVC]) and bone mineral density (BMD), bone volume fraction (BVF), hematologic bone metabolic factors (I), and identify indicators of implant failure (II). Material and Methods: Forty‐six consecutive patients had their edentulous atrophic maxilla reconstructed with free autogenous bone grafts from anterior iliac crest. Endosteal implants were placed 6 months after graft healing. Computer tomography was performed after 3 weeks and 6 months after grafting. Bone biopsies were taken from the internal table of donor site for calculation (BVF), and blood samples were collected. Implant stability was measured at placement with resonance frequency analysis and expressed as implant stability quotient (ISQ). Implant failure was registered. Results: GVC in onlay bone graft was 37%. The BVF in iliac crest biopsies was 32%. Serum‐IGFBP3 differed with 79% of the samples over normal range. Fifteen patients had one or more implant failures prior to loading (early failures). Forty‐two patients were followed for a minimum of 3 years after implant loading and, in addition, 6/42 patients had one or more implants removed during the follow‐up (late failures). GVC correlated to decreased BMD of lumbar vertebrae L2‐L4 (Kruskal–Wallis test, p = .017). No correlation was found between GVC and hematologic factors (Pearson correlation test) or between GVC and BVF (Kruskal–Wallis test). No correlation was found between ISQ and GVC (Pearson correlation test, p = .865). The association between implant failures and the described factors were evaluated, and no significant correlations were found (unconditional logistic regression). Conclusion: Onlay bone grafts decrease 37% during initial healing period, which correlate to BMD of lumbar vertebrae L2‐L4. No other evaluated parameters could explain GVC. The evaluated factors could not explain implant failure. 相似文献
912.
����λ�㱣�漼�� 总被引:1,自引:0,他引:1
拔牙位点保存技术是为了预防及减少牙槽嵴的废用性萎缩吸收及牙龈乳头的退缩,使牙槽嵴骨量的高度、宽度及密度满足后期种植的需要,并使牙龈乳头恢复正常高度以满足美学要求的一种方法。本文就拔牙后牙槽窝的生理性变化、牙槽骨及软组织的保存方法及现有的植骨材料做一介绍。 相似文献
913.
G. Passari S. Lentini F. Benedetto M. La Spada Fr. Spinelli 《Acta chirurgica Belgica》2013,113(3):383-386
Retroperitoneal leiomyosarcoma arising in, or involving, the inferior vena cava or the iliac vein are infrequent tumours. They are usually treated by “en-block” surgery. Venous reconstruction is usually not needed, since collateral circulation can adequately offset the main vessel flow. However, in rare cases, collateral circulation may be insufficient. The authors report a case of leiomyosarcoma infiltrating the left iliac vein. One week after radical resection surgery, the patient developed left leg compartmental syndrome due to venous hypertension.The patient was successfully treated by thrombectomy of the left femoral vein and cross-femoral venous bypass (Palma’s Procedure) by means of an 8 mm diameter polytetrafluoroethylene (PTFE) prosthesis. To improve the flow inside the graft, an arterio-venous fistula (AVF) was performed. The choice of a prosthetic conduit, its diameter, and the AVF are discussed. 相似文献
914.
Mehmet Odabasi Cengiz Eris Mehmet Kamil Yildiz Hasan Abuoglu Sami Akbulut Abdullah Saglam 《International surgery》2013,98(3):277-281
Hepatic artery aneurysms are responsible for 12% to 20% of all visceral arterial aneurysms. Because most patients are asymptomatic, this disease is generally diagnosed incidentally during radiologic examination. Aneurysm rupture develops in 14% to 80% of cases, depending on the aneurysmatic segment''s diameter and location, as well as other etiologic factors. Mortality rates associated with rupture range between 20% and 70%. Thus, early diagnosis and timely initiation of medical interventions are critical to improve survival rates. Here, we present a male patient, age 69 years, with a hepatic artery aneurysm that was detected incidentally. The 3-cm aneurysm was detected on contrast-enhanced computed tomography and extended from the common hepatic artery to the hepatic trifurcation. A laparotomy was performed using a right subcostal incision. After dissection of the hepatoduodenal ligament, the common, right, and left hepatic arteries, as well as the gastroduodenal artery, were suspended separately. Then, the aneurysmatic hepatic artery segment was resected, and the gastroduodenal artery stump was ligated. An end-to-end anastomosis was formed between the left and common hepatic arteries, followed by an end-to-end anastomosis formed between the right hepatic artery and splenic artery using a splenic artery transposition graft. Postoperative follow-up examinations showed that both hepatic arterial circulations were good, and no splenic infraction had developed. 相似文献
915.
Zheng WangLiang Yu MD PhD Wanli WangJianmin Xia MD Dai LiYi Lu MD PhD Bo Wang 《The Journal of surgical research》2013
Background
The incidence of vascular injury after a cholecystectomy is often underestimated. Although injuries to the portal vein are rare, they are devastating. The aim of the present study was to analyze suitable therapeutic strategies regarding portal vein injury in the absence of biliary injury.Materials and methods
Eleven patients with portal vein injuries after laparoscopic or open cholecystectomy were referred to our hospital between 2004 and 2010. The clinical presentation, diagnosis, and management of patients with severe portal vein injuries were reviewed. All the patients were discharged without outstanding clinical conditions. During retrospective analysis, these patients were divided into early, middle, and late stages.Results
All the 11 patients had a portal vein and/or right hepatic artery injury, but no biliary injuries were observed. Among these patients, different management strategies were managed according to the stage of the injury. Eight patients received a direct suture at the time of injury by an experienced hepatobiliary surgeon. Two patients received thrombolytic and anticoagulation therapy after cholecystectomy, without additional surgery. One patient received a liver transplant 3 mo after the injury. After long-term follow-up, these patients had no clinical conditions.Conclusions
Direct repair or suture is important during the early stage of portal vein injury. Conservative thrombolytic and anticoagulation therapy may serve an important role in the treatment of acute massive thrombus in portal vein injury during the middle stage. Liver transplantation is a salvage therapy that should be used during the late stage. 相似文献916.
Posttraumatic osteonecrosis of distal pole of scaphoid is an extremely rare with only two reported cases so far. We present a case of a 30-year-old male with a 2-year-old posttraumatic osteonecrosis and nonunion of distal pole of scaphoid left wrist. He presented with complaints of pain and restriction of movements. There was no evidence of radiocarpal arthritis. He was managed with open reduction and internal fixation with k-wires, supplemented by a pronator quadratus based muscle pedicle bone graft. The fracture union was achieved at 6 months. After 2 years, he had almost complete range of wrist motion and had returned to his preinjury level of functional activity. His MRI (magnetic resonance imaging) scans showed evidence of revascularization suggesting successful incorporation of bone graft. 相似文献
917.
Introduction
Current guidelines on venous thromboembolism (VTE) prevention do not reflect the potential varying risk for patients undergoing different urological procedures. Our study aimed to establish the procedure specific rate of postoperative VTE in patients undergoing urological surgery.Methods
Hospital Episode Statistics were obtained for all patients undergoing common urological procedures between April 2009 and April 2010. This cohort was followed up to identify all patients reattending with either deep vein thrombosis (DVT) or pulmonary embolism (PE) within 12 months.Results
A total of 126,891 individuals underwent urological surgery during the study period. This included 89,628 men (70.6%) and 37,236 women (29.3%) with a mean age of 65.2 years. At the 12-month follow-up, 839 patients (0.66%) were readmitted with VTE. Of these, 373 (0.29%) were admitted with DVT and 466 (0.37%) with PE. The procedure-specific rate of VTE varied significantly between 2.86% following cystectomy and 0.23% following urethral dilatation. Procedures performed in the lithotomy position carried a significantly lower risk of VTE than those performed in the supine position (0.60% vs 1.28%, p<0.0001). Furthermore, of all procedures performed in the lithotomy position, those performed on benign conditions carried a significantly lower risk than those performed on malignant disease (0.52% vs 0.79%, p<0.0001).Conclusions
Procedure specific rates of postoperative VTE vary widely among patients undergoing urological procedures. These findings suggest the potential benefit of prolonging the use of thromboprophylaxis in high-risk patients but also exploring the apparent lack of need for routine thromboprophylaxis in patients undergoing low-risk procedures. 相似文献918.
C Lin L Wang Q Lu C Li Z Jing 《Annals of the Royal College of Surgeons of England》2013,95(2):134-139
Introduction
This study aimed to evaluate the feasibility of total endovascular repair of the aortic arch in pigs using improved integrated double-branched stent grafts.Methods
Improved self-expandable stent grafts with a main body and two integrated branches were prepared for the repair of the aortic arch in six pigs. The feasibility of using these stent grafts was evaluated with arteriography, computed tomography (CT), computed tomography angiography (CTA) and autopsy three months following the procedure.Results
The double-branched stent grafts were placed successfully in the aortic arch in all six pigs. All pigs survived for at least three months and their biological behaviour was normal. Arteriography, CTA and animal necropsy revealed good fixation in all cases. Aortic valve function and coronary ostia remained intact, and CT of the head did not detect any lesion of cerebral infarction.Conclusions
Endovascular repair of the aortic arch with an integrated double-branched stent graft is safe and feasible in animal studies. 相似文献919.
Primary graft failure (PGF) caused by ischemia‐reperfusion injury (IRI) is the strongest determinant of perioperative mortality after heart transplantation. Atrial natriuretic peptide (ANP) has been found to reduce the IRI of cardiomyocytes and may be beneficial in alleviating PGF after heart transplantation, although there is a lack of evidence to support this issue. The purpose of this study was to investigate the cardioprotective effects of ANP after prolonged hypothermic storage. For this purpose, an isolated working‐heart rat model was used. After the preparation, the hearts were arrested with and stored in an extracellular‐based cardioplegic solution at 3–4°C for 6 h and followed by 25 min of reperfusion. The hearts were divided into four groups (n = 7 in each group) according to the timing of ANP administration: Group 1 (in perfusate before storage), Group 2 (in cardioplegia), Group 3 (in reperfusate), and control (no administration of ANP). Left ventricular functional recovery and the incidence of ventricular fibrillation (VF) were compared. ANP administration at the time of reperfusion improved the percent recovery of left ventricular developed pressure (control, 45.5 ± 10.2; Group 1, 47.4 ± 8.8; Group 2, 45.3 ± 12 vs. Group 3, 76.3 ± 7; P < 0.05) and maximum first derivative of the left ventricular pressure (control, 47.9 ± 8.7; Group 1, 46.7 ± 8.8; Group 2, 49.6 ± 10.8 vs. Group 3, 76.6 ± 7.5; P < 0.05). The incidence of VF after reperfusion did not differ significantly among these four groups (71.4, 85.7, 57.1, and 85.7% in Groups 1, 2, 3, and control, respectively). This result suggests that the administration of ANP at the time of reperfusion may have the potential to decrease the incidence of PGF after heart transplantation. 相似文献
920.
目的 通过术前选择合适的供肝、术中建立充分的流出道及术后调整门静脉压等综合措施预防活体肝移植术后肝小体积综合征.方法 总结2007年12月至2009年11月的113例活体肝移植的临床资料,术前通过影像系统评估供肝体积,测算供肝体积与受者体重比(GRWR),根据供肝解剖及GRWR确定采用的供体类型(含肝中静脉右半肝,不含肝中静脉右半肝,含肝中静脉左半肝等),术中通过建立充分的流出道,根据GRWR、术前脾功能亢进情况、肝动脉开放后门静脉血流量及门静脉压力,确定是否采用脾动脉结扎等方法将门静脉压力控制在<20 mm Hg(2.67 kPa),门静脉血流量控制在<250 ml·min-1·100 g-1,观察采取上述措施后肝小体积综合征的发生情况.结果 75例受者接受含肝中静脉的右半肝,37例接受不含肝中静脉的右半肝,1例接受含肝中静脉左半肝.随访6个月,所有受者均未出现持续黄疸、败血症等严重的肝小体积综合征表现,1例受者于术后42 d死于脑卒中及呼吸衰竭,受者术后6个月存活率为99.1%(112/113).结论 术前根据供肝血管解剖及GRWR选择适当的供肝类型,术中建立充分的流出道,通过脾动脉结扎等方式调整门静脉血流及压力的综合方法可有效预防肝小体积综合征. 相似文献