Reconstruction Of Abdominal Aortic Aneurysm Research Articles

Multifaceted surgical approach of combined thoracoretroperitoneal incision and midline abdominal incision for a secondary aortoenteric fistula

BackgroundWe report a one-stage surgery to the case of secondary aortoenteric fistula (sAEF) after prosthetic reconstruction of abdominal aortic aneurysm, by multifaceted approach.Case presentationA 63-year-old male was admitted to our unit under diagnosed of sAEF after prosthetic reconstruction of abdominal aortic aneurysm, and a pseudoaneurysm of thoracoabdominal aorta due to infection. The patient underwent emergency operation. Firstly, we placed the patient in a modified right lateral decubitus position and performed thoracoabdominal aortic replacement with retroperitoneal approach by thoracoretroperitoneal incision which combined thoracotomy and pararectal incision, and secondly, we changed to a supine position and performed closure of the duodenal fistula and omental flap transposition by midline abdominal incision. The patient was doing well without complications.ConclusionsA one-stage, multifaceted surgical approach covering both prosthetic reconstruction of thoracoabdominal aorta and closure of sAEF with omentopexy is reasonable and useful strategy.

Features of Diagnosis and Surgical Treatment of Abdominal Aortic Aneurysms with a Horseshoe Kidney

Introduction. Reconstructive surgery of abdominal aortic aneurysms, despite significant international experience, remains one of the most complex issues of current vascular surgery, especially due to anatomical variability of arterial blood supply of the kidneys and abnormalities in their development, among which the most common is a horseshoe kidney. Features of vascularization, placement of the renal isthmus relative to the main vessels, the choice of the optimal method of abdominal aortic aneurysm reconstruction cause a high risk of surgery. The issues of open and endovascular aortic grafting, possibility of crossing the isthmus of the horseshoe kidney, feasibility of reconstruction of additional renal arteries still remain controversial.
 The aim. Improvement of the diagnosis and surgical treatment of abdominal aortic aneurysms with a horseshoe kidney.
 Case presentation. In our observation, in a 61-year-old patient, by clinical examination, laboratory and diagnostic imaging the diagnosis of two infrarenal abdominal aortic aneurysms with a horseshoe kidney was confirmed, that has become a direct indication for surgical intervention: exclusion of infrarenal aortic aneurysms from the blood flow, abdominal aortic prosthetic grafting with reimplantation of the renal isthmus arteries into the prosthetic graft. This clinical case confirms the advantages of open surgical technique, using transperitoneal approach, which not only provided sufficient exposure of the operating area, but also allowed to perform optimal reconstruction of the abdominal aorta without crossing the functioning isthmus of the horseshoe kidney with preservation of blood flow through additional renal arteries.
 Conclusion. Careful preoperative assessment of the peculiarities of the blood supply of the horseshoe kidney with coexistent abdominal aortic aneurysms allows to optimize the tactics of surgical treatment, prevent the development of severe complications and achieve complete recovery of the patient.

Three-Dimensional Reconstruction of Abdominal Aortic Aneurysm Based on Compressive Sensing With Iterative Optimization and Its Application in 3D Printing

Three-dimensional reconstruction of abdominal aortic aneurysm is the key technology to improve the success rate of surgical and reduce complications. However, the outer contour of abdominal aortic aneurysm(AAA)is fuzzy, which make it difficult for recent existing method to obtain its accurate segmentation performance and high reconstruction accuracy. In this paper, an improved compressive sensing reconstruction algorithm is proposed, which defines a differentiable and convex total variation (TV) function as an optimization goal function and further reduces the number of projections and improve the quality of reconstructed images. Our proposed algorithm improves the speed and stability of the reconstruction algorithm in three-dimensional reconstruction of abdominal aortic aneurysm. The experimental results show that the proposed model can be used for 3D modeling in 3-D printing to improve the accuracy of endovascular repair and the adaptability of the stent, which is suitable for the application of bioengineering medicine.

Endovascular repair of proximal para-anastomotic aneurysms after previous open abdominal aortic aneurysm reconstruction.

To evaluate the safety, efficacy and durability of endovascular repair for proximal para-anastomotic aneurysms after previous open abdominal aortic aneurysms prosthetic reconstruction and share our experience. We retrospectively reviewed the data of all patients with previous open abdominal aortic aneurysms prosthetic reconstruction who underwent endovascular repair for proximal para-anastomotic aneurysms between May 2003 and January 2013 in our center (Nuremberg South Hospital). Key clinical outcomes included technical success rate, peri-operative morbidity and mortality, mid-term complications, reinterventions and open conversion rates. Totally, 24 patients of proximal para-anastomotic aneurysm were treated by endovascular repair. Successful deployments of stent graft were achieved in all patients (100%). Median hospital stay was 6.7 days. One patient had minor type Ia endoleak and one patient developed wound infection. There were no early open conversions and deaths. During a median follow-up of 43 months (range, 7-67 months), computed tomography angiography revealed type Ia endoleaks in four patients (16.7%). The overall reintervention and open conversion rates during follow-up were 16.7% (4/24) and 4.2% (1/24), respectively. Estimates of freedom from reintervention were 91.7% at 1 year, 87.1% at 3 years and 80.9% at 5 years. There was significant difference in freedom from reintervention between proximal para-anastomotic aneurysms patients treated with tube and unibody bifurcated stent grafts (p = 0.034). The cumulative mortality rate was 12.5% (3/24), actuarial analysis for all patients estimated survival rates of 95.8% at 1 year and 87.3% at 5 years. Proximal para-anastomotic aneurysms are severe complications after abdominal aortic aneurysm open reconstruction. Closer follow-up and prompt treatment are necessary. Endovascular treatment for proximal para-anastomotic aneurysms is effective, safe and durable. Unibody bifurcated stent graft proved to be suitable for most proximal para-anastomotic aneurysms with various anatomical features.

Semi-Automatic Segmentation of Ct/Mri Images Based on Active Contour Method for 3D Reconstruction of Abdominal Aortic Aneurysms

Abstract Abstract The paper presents a CT/MRI image based semi-automatic AAA (abdominal aortic aneurysm) segmentation method. Segmentation process can run automatically with the active contour method but results are controlled by the operator. If incorrect segmentation is noticed, the operator may introduce corrections. The proposed method makes possible the segmentation of dissected aneurysms, with which no automatic analysis works. Controlling the segmentation process by the operator serves to ensure correct geometric shape reproduction, which is crucial in deploying aneurysm models to help assess rupture risk.

Long‐Term Survival and Quality of Life After Open Abdominal Aortic Aneurysm Repair

Open repair of abdominal aortic aneurysm (AAA) generally involves postsurgery admission to the intensive care unit (ICU). Few studies have evaluated the impact of surgery for either ruptured or nonruptured AAA (with postoperative ICU treatment) on long-term survival and quality of life. The primary aim of this study was to quantify long-term survival and health-related quality of life (HrQpL) of a cohort of patients undergoing open AAA repair after hospital discharge. Consecutive patients undergoing open elective or acute AAA reconstruction with postoperative admission to the ICU and discharged alive from the hospital during 2009 were identified. Primary outcome measures were 1-year and long-term mortality. The secondary outcome was the HrQoL using the EuroQol-6D (EQ-6D) questionnaire at the end of the follow-up period. A total of 263 patients were treated and postoperatively discharged alive: 56 had a ruptured AAA (rAAA), 35 a symptomatic AAA, and 172 an asymptomatic AAA. The 1-year mortality after open AAA repair was 8 %. Overall, 39 % of patients died within 10 postoperative years (mean 6.0 ± 2.8 years). Long-term survival of patients with a ruptured or symptomatic aneurysm was similar to that of patients undergoing elective aneurysm repair. Long-term HrQoL of the total study population was worse than that of an age-matched general Dutch population on the EQ-us (range 0-1, difference 0.12). This decrease in HrQoL was mainly seen in mobility, self-care, usual activities, and cognition. Ten years after open AAA repair, the overall survival rate was 59 %. Long-term survival and HrQoL were similar for patients with a repaired ruptured or symptomatic aneurysm and those who underwent elective aneurysm repair. There were also no differences in patients with infrarenal versus juxtarenal/suprarenal aneurysms. Surviving patients had a lower HrQoL than the age-matched general Dutch population, especially regarding mobility, self-care, usual activities, and cognition.

Discrepancies in determination of abdominal aortic aneurysms maximum diameter and growth rate, using axial and orhtogonal computed tomography measurements

PurposeMaximum diameter and growth rate of abdominal aortic aneurysms (AAAs) which are currently used as the only variables to set the indication for elective repair are recorded through computed tomography (CT) measurements on an axial plane or on an orthogonal plane that is perpendicular to vessel centerline, interchangeably. We will attempt to record possible discrepancies between the two methods, identify whether such differences could influence therapeutic decisions and determine in which cases this should be expected. Materials and methodsWe retrospectively reviewed sixty CT-scans performed in thirty-nine patients. Three-dimensional reconstruction of AAAs has been performed and differences in maximum diameter measured on axial and orthogonal planes were recorded. A measure for asymmetry was introduced termed ShapeIndex defined as the value of section minor over major axis and was related with differences in maximum diameter recordings. Growth rates were also determined using both axial and orthogonal measurements. ResultsAxial measurements overestimate maximum diameter by 2±2.7mm (P<0.001) with a range of 0–12.3mm. Overall, 20% of the CTs had an axial maximum diameter >5.5cm indicating the need for intervention whereas, orthogonal diameter was below that threshold. Asymmetry of the axial sections with ShapeIndex≤0.8 was found to be related to an overestimation of maximum diameter by >5mm. There were no significant differences in growth rates when determined using orthogonal or axial measurements in both examinations (median growth rate: 2.3mm and 3.3mm respectively P=0.2). However there were significant differences when orthogonal measurements were used at initial and axial measurements used at follow-up examination or vice versa (median growth rate: 4.9mm and 0.9mm respectively P<0.001). ConclusionsAlthough the mean difference between measurements is low there is a wide range among cases, mainly observed in asymmetrical AAAs. ShapeIndex may identify those which are more likely to be misestimated. CT measurements performed to establish AAA growth rates should consistently use either the axial or orthogonal technique to avoid inaccuracies from occurring.

Comparison of retroperitoneal and transperitoneal approach for reconstruction of abdominal aortic aneurysm in patients with previous laparotomy

Although the standard surgical approach for repair of infrarenal abdominal aortic aneurysm (AAA) has been the transperitoneal approach, several reports have suggested the usefulness of retroperitoneal aortic reconstruction. However, the superiority of the retroperitoneal compared with transperitoneal approach is still controversial. To compare the efficacy of the retroperitoneal with that of the transperitoneal approach in elective AAA resection, 19 consecutive cases with previous laparotomies were randomly reviewed. From January 1990 through December 1992, 94 consecutive patients underwent elective reconstructions of an infrarenal AAA. Among them, 75 patients had had no previous surgery of any kind. In all of them, the transperitoneal approach was used (Group I). Nineteen other patients who had various laparotomies were randomly divided into two groups. The transperitoneal approach was used in 10 patients (Group II), and the retroperitoneal approach was used in 9 patients (Group III). Thus, the patients were separated into three groups and the intra- and postoperative parameters were compared. Surgical data including operative time, intraoperative blood loss, and aortic cross-clamping time did not differ significantly between the transperitoneal approach in the patients without laparotomy (Group I) and the retroperitoneal approach (Group II). In addition, the postoperative recovery including the initiation of alimentation and postoperative hospitalization also did not differ significantly between the two groups. However, there was a significant difference in the operative time and the blood loss between the retroperitoneal approach (Group II) and transperitoneal approach (Group III) in the patients with previous laparotomy. In addition, the postoperative parameters including the initiation of oral intake was sooner and hospitalization was significantly shorter in the retroperitoneal group (Group II) than in the transperitoneal group (Group III) with previous laparotomy. There was no incidence of postoperative adhesive ileus in the patients with the retroperitoneal approach (Group II). The results demonstrated no important advantage for the retroperitoneal approach compared with routine transperitoneal approach in the patients without previous laparotomy. However, in the patients with previous laparotomies, the retroperitoneal approach is a preferable alternative to the transperitoneal route.

The impact of model assumptions on results of computational mechanics in abdominal aortic aneurysm

In principle, superiority of computational wall stress analyses compared with the maximum diameter criterion for rupture risk evaluation of abdominal aortic aneurysm (AAA) has been demonstrated. The results of finite element analyses should be evaluated carefully, however, because computational strains and stresses are highly dependent on the quality and complexity of each step of AAA simulation. Most clinically active vascular specialists are not familiar with the processes of computational mechanics to evaluate the quality of AAA simulations. For better understanding and to provide insights in computational biomechanics of AAA, the effect of different computational model assumptions on the results of simulation are explained and demonstrated. Four patients with asymptomatic (n = 3) and symptomatic (n = 1) infrarenal AAAs with distinctly different aneurysm morphologies were exemplarily studied. For segmentation and 3-dimensional (3D) reconstruction of AAA and thrombus, 3-mm computed tomography (CT) slices were used, and a high-density hexahedral element-dominated finite element mesh was generated. Subsequent AAAs were simulated on seven different levels, culminating in the most realistic ortho-pressure-finite element analyses simulations, including thrombus, wall calcifications, and prestress state of AAA geometry with nonlinear hyperelastic material and geometric model assumptions. Alterations in displacements due to model assumptions are up to 740% for a specific aneurysm. The average maximum discrepancy among the four morphologies between simple and advanced models is 607%. Differences in peak wall stress between simple and realistic models are up to 210% individually and 170% on average. Differences of model assumptions are more important for simulation results than differences between patient-specific morphologies. Because the biomechanical behavior of AAA is nonlinear in many senses, comparisons between individual morphologies and statistics are only valid when detailed information about preconditions and model assumptions is provided.

Three Dimensional Active Contours for the Reconstruction of Abdominal Aortic Aneurysms

An aneurysm is a gradual and progressive ballooning of a blood vessel due to wall degeneration. Rupture of abdominal aortic aneurysm (AAA) constitutes a significant portion of deaths in the US. In this study, we describe a technique to reconstruct AAA geometry from CT images in an inexpensive and streamlined fashion. A 3D reconstruction technique was implemented with a GUI interface in MATLAB using the active contours technique. The lumen and the thrombus of the AAA were segmented individually in two separate protocols and were then joined together into a hybrid surface. This surface was then used to obtain the aortic wall. This method can deal with very poor contrast images where the aortic wall is indistinguishable from the surrounding features. Data obtained from the segmentation of image sets were smoothed in 3D using a Support Vector Machine technique. The segmentation method presented in this paper is inexpensive and has minimal user-dependency in reconstructing AAA geometry (lumen and wall) from patient image sets. The AAA model generated using this segmentation algorithm can be used to study a variety of biomechanical issues remaining in AAA biomechanics including stress estimation, endovascular stent-graft performance, and local drug delivery studies.

Endovascular treatment of a triple paraanastomotic aneurysm after aortobiiliac reconstruction

We report a case of a 72-year-old patient considered unfit for open surgery, presenting with paraanastomotic aneurysms of all three anastomoses, 13 years after an open aortobiiliac reconstruction for abdominal aortic aneurysm. This patient was successfully treated with an endovascular approach using a left aortouniiliac endograft and a right iliac tubular endograft, followed by crossover femorofemoral bypass. This report illustrates the usefulness of a minimally invasive approach for solving this complication of aortic open surgery and discusses technical issues related to endovascular devices in this particular setting.

Internal iliac artery aneurysm rupture with aorto-enteric fistula after reconstruction of abdominal aortic aneurysm: report of a case

Internal iliac artery aneurysm rupture with aorto-enteric fistula after reconstruction of abdominal aortic aneurysm: report of a case

Three-dimensional shape reconstruction of abdominal aortic aneurysm

This paper presents an effective computational technique for reconstructing a three-dimensional shape of an abdominal aortic aneurysm (AAA), from a limited number of computed tomography (CT) images. The three-dimensional template geometry of a healthy abdominal aorta is used as a priori knowledge, and the template geometry is deformed by extended free-form deformation (EFFD), to generate a patient-specific AAA geometry. A two-step optimization scheme is devised to find an optimal set of EFFD parameters that match the cross-section of a deformed template with an AAA contour shown in a CT image. The geometric continuity of a deformed model is maintained by raising the order of the polynomial function used in EFFD. Experimental results show that the proposed method creates the three-dimensional shape of AAA suitable for structural finite element analysis and computational fluid dynamics for medical diagnosis.

Ischaemic lumbosacral plexopathy following aorto-iliac bypass graft: case report and review of literature

A 77-year-old man had aorto-iliac bypass for an abdominal aortic aneurysm (AAA). This was complicated by occlusion that needed extension of the graft to the right femoral artery. He was unable to move his right leg with numbness after surgery. This was caused by extensive lumbosacral plexopathy on the right side. Lumbosacral plexopathy is uncommon because the plexus has a rich blood supply. The incidence of ischaemic lumbosacral plexopathy is higher with re-operative and emergency AAA reconstruction. This may predispose the lumbosacral plexus to ischaemic injury. Consideration should be given to maintaining retrograde perfusion of the internal iliac artery.

Congenital Anomalies of the Inferior Vena Cava and Left Renal Vein: Implications during Open Abdominal Aortic Aneurysm Reconstruction

Although uncommon and usually incidental findings on imaging or at operation, congenital anomalies of the retroperitoneal venous system, particularly those involving the inferior vena cava and left renal vein, can be troublesome and dangerous during open repair of abdominal aortic aneurysms (AAA). We have provided a retrospective analysis of our single tertiary institution experience with these anomalies during more than 2400 open AAA reconstructions in an effort to determine if preoperative identification of these vessels decreased venous injury and subsequent morbidity as well as offering a thorough review of the relevant embryology, anatomy, and technical approaches for each specified anomaly for the practicing vascular surgeon.

Intraoperative Peripherally Inserted Central Venous Catheter Central Venous Pressure Monitoring in Abdominal Aortic Aneurysm Reconstruction

Numerous studies have found no clinically significant benefit to the perioperative use of pulmonary artery catheters (PACs), and peripherally inserted central venous catheters (PICCs) have been reported to measure central venous pressure (CVP) accurately. The objective of this study was to determine whether the dynamic shifts in preload associated with elective reconstruction of abdominal aortic aneurysms (AAAs) are accurately reflected by CVP measurements from open-ended PICCs compared to CVP measurements from concomitant indwelling PACs. This is a retrospective review of prospectively collected data. PICCs and PACs were placed preoperatively in five patients undergoing elective AAA reconstruction. CVP measurements were recorded every 15 min during the operation. Bland-Altman statistical analysis was used to determine the degree of agreement in data collected by the two measurement devices. Seventy-three paired measurements of CVP from concomitant indwelling PICCs and PACs obtained from five patients undergoing elective AAA reconstruction revealed PICC measurements to be higher than PAC measurements by 0.6 mm Hg (overall correlation coefficient 0.92). The difference between the two measurement devices was expected to be <3.4 mm Hg at least 95% of the time. The findings of this pilot study indicate that PICCs are an effective method for CVP monitoring in situations of dynamic systemic compliance and preload, such as those observed during elective AAA reconstruction.

Changes of low back pain after vascular reconstruction for abdominal aortic aneurysm and high aortic occlusion: a retrospective study

Background The purpose of the present study is to clarify the influence of acute and chronic interruption of blood flow from lumbar arteries as well as the influence of vascular reconstruction on low back pain, back muscles, and lumbar discs. Methods Subjects were 34 patients with AAA in whom vascular reconstruction was performed. A second group was comprised of 9 patients with HAO. The presence of low back pain before surgery and at follow-up examination was retrospectively examined in the AAA group and the HAO group to investigate postoperative changes. The CSA and degeneration of the multifidus muscle and the lumbar discs on magnetic resonance imaging were assessed in the AAA group and control group. Results Low back pain, significant atrophy, or degeneration of the multifidus muscle or degeneration of the lumbar disc did not newly develop after surgery in the AAA group. These results indicated that acute interruption of lumbar arteries did not induce the development or deterioration of low back pain and organic changes in the back muscles or lumbar discs. The frequency of low back pain before surgery was significantly higher in the HAO group than that in the AAA group. However, the frequency of low back pain after surgery did not differ significantly between the 2 groups because low back pain in the HAO group was improved after surgery. Conclusion The finding that low back pain was improved by merely performing treatment for the vascular system might provide support for the presence of vascular backache.

Correção de aneurisma de aorta abdominal em paciente com dois rins pélvicos

Abdominal aortic aneurysm reconstruction is usually performed in vascular surgical practice. However, the repair of an abdominal aortic aneurysm associated with a pelvic kidney is rare. Our goal is to present a case report of an abdominal aortic aneurysm associated with two congenital pelvic kidneys wich was treated successfully by aneurysmectomy and inclusion of an aortoaortic graft.

Predictors of development of anastomotic femoral pseudoaneurysms after aortobifemoral reconstruction for abdominal aortic aneurysm

Background The pathogenesis of anastomotic femoral pseudoaneurysms (AFPs) is still unclear. We have performed this long-term retrospective study of patients who underwent aortobifemoral reconstruction for abdominal aortic aneurysm (AAA) in order to better establish the long-term rate of AFP and to identify the predictors of its late occurrence. Methods The long-term outcome of 178 patients who underwent and survived aortobifemoral reconstruction for infrarenal AAA was reviewed. Results During a median follow-up of 5.2 years, 28 AFPs developed in 19 patients. Six AFPs were recurrent. The mean linearized rate of AFPs was 1.88% per year. At 15 years, the survival-freedom rate from AFPs was 60%, and from repair of AFPs it was 62%. The survival-freedom rate from AFP was significantly poorer in patients with chronic obstructive pulmonary disease ( P = 0.017; at 10 years: 64.3% versus 92.3%), hyperlipidemia ( P = 0.0056; at 10 years: 59.2% versus 87.5%), current smoking ( P <0.0001; at 10 years: 65.8% versus 94.5%), and postoperative inguinal wound infection ( P <0.0001; at 10 years: 42.8% versus 86.8%). Multivariate analysis showed that chronic obstructive pulmonary disease (relative risk [RR]: 3.05, 95% confidence interval [CI]: 1.04 to 8.95), current smoking (RR: 5.38, 95% CI: 1.62 to 17.90), and postoperative inguinal wound infection (RR: 9.04, 95% CI: 2.76 to 29.96) were significantly associated with the development of AFPs. The linearized rate of AFPs was significantly higher only among current smokers ( P <0.0001, 4.4% versus 0.8% per year) and among those who had inguinal wound infection ( P = 0.001, 9.2% versus 1.5% per year). Conclusions Current smoking and inguinal wound infection may contribute to the development of AFP after aortobifemoral reconstruction for AAA, likely by affecting reparative connective tissue mechanisms at the anastomotic site.

Hospital mortality after Abdominal Aortic Aneurysm Reconstruction

Hospital mortality after Abdominal Aortic Aneurysm Reconstruction