VIRTUAL REALITY BASED THREE-DIMENSIONAL GUIDE WIRE PROPAGATION SIMULATION FOR ENDOVASCULAR INTERVENTION

The virtual reality based motion simulation of the guide wire and the catheter inside specific vascular structures can benefit a lot for the endovascular intervention. A fast and well-performed collision cancellation algorithm is proposed based on the geometric analysis and the angular propagation （AP）, and a 3-D real-time interactive system is developed for the motion simulation of the guide wire and the catheter inside the specific patient vascular. The guide wire or the catheter is modeled as the ＂multi-body＂ representation and properties are defined by its intrinsic characteristics. The motion of the guide wire or the catheter inside the vascular is guided by the collision detection and the collision cancellation algorithm. Finally, a relaxation procedure is used to achieve more realistic status. Experimental results show that the behavior of the guide wire or the catheter depends on the defined parameters. The real-time simulation can be achieved. The result shows that the simulation system is effective and promising.

Multidisciplinary management of acute mesenteric ischemia:Surgery and endovascular intervention

Acute mesenteric ischemia(AMI)is a rare cause of the“acute abdomen”,characterized by impaired blood flow to the intestine.The principle of treatment is restoration of perfusion to ischemic bowel and resection of any necrotic intestine.Surgery and endovascular intervention are two complementary approaches to mesenteric ischemia.Endovascular intervention is not an alternative to the surgical approach,but it has the potential to improve the prognosis of patients with AMI when judiciously combined with a surgical approach.Due to the need for emergent treatment of patients with acute mesenteric ischemia,the treatment strategy needs to be modified for each facility.This review aims to highlight cutting-edge studies and provide reasonable treatment strategies for patients with acute mesenteric ischemia based on available evidence.

Prospective Randomized Study of Sarpogrelate Versus Clopidogrel-based Dual Antiplatelet Therapies in Patients Undergoing Femoropopliteal Arterial Endovascular Interventions： Preliminary Results

Background：Sarpogrelate is a selective 5-hydroxytryptamine （5-HT） receptor subtype 2A antagonist which blocks 5-HT induced platelet aggregation and proliferation of vascular smooth muscle cells.We compared the efficacy of sarpogrelate-based dual antiplatelet therapies for the prevention of restenosis and target lesion revascularization （TLR） rates comparing with that of clopidogrel after percutaneous endovascular interventions （EVIs） of femoropopliteal （FP） arterial lesions.Methods：This prospective,multicenter,randomized clinical trial recruited a total of 120 patients with successful EVI of FP lesions at seven centers across China between January 2011 and June 2012.Patients were randomized to receive either sarpogrelate （100 mg trice daily for 6 months,n =63） or clopidogrel （75 mg once daily for 6 months,n =57）.All patients also received oral aspirin （100 mg once daily for 12 months）.Clinical follow-up was conducted up to 12 months postprocedure.Results：There was no significant difference between the two groups in basic demographic data.The restenosis rate was higher in the clopidogrel group （22.80%） than in sarpogrelate group （17.50%）,but there was no significant difference between these two groups （P =0.465）.The TLR rate,ipsilateral amputation rate,mortality in all-cause and bleeding rate were also similar in the two groups （P 〉 0.05）.Conclusions：Aspirin plus sarpogrelate is a comparable antithrombotic regimen to aspirin plus clopidogrel after EVI of FP arterial lesions.Dual antiplatelet therapies might play an important role in preventing restenosis after successful EVI of FP lesions.

Cystic artery pseudoaneurysm:A case report

BACKGROUND Cystic artery pseudoaneurysm is a condition rarely encountered by clinicians;this,its etiology and presentation as well as appropriate treatments are not well studied.Although it is treated by removal of the diseased gallbladder and cystic artery,such surgery can be difficult and risky if acute inflammation with bleeding occurs,and not every patient can tolerate the surgery.CASE SUMMARY An 81-year-old man complained of epigastric pain and tarry stool passage that lasted for 3 d.He had a medical history of poor cardiopulmonary function.The computed tomographic scan of abdomen showed cystic artery pseudoaneurysm and dilatation of gallbladder.Because of high adverse outcomes related to general anesthesia,the patient was successfully managed with endovascular embolization for this cystic artery pseudoaneurysm and percutaneous drainage for the distended gallbladder.CONCLUSION A patient with cystic artery pseudoaneurysm may quickly deteriorate with the occurrence of concurrent arterial bleeding and sepsis.This report presents the case of a patient who did not undergo surgery due to multiple cardiopulmonary comorbidities and whose condition was managed successfully with embolization and biliary drainage.Endovascular embolization and biliary drainage may provide an alternative option to manage this complicated condition.

Budd-Chiari syndrome in children:Challenges and outcome

Budd-Chiari syndrome(BCS)is an uncommon disease of the liver,characterised by obstruction of the hepatic venous outflow tract.The etiological spectrum of BCS as well as venous obstruction pattern show wide geographical and demographic variations across the globe.Compared to adults with BCS,children have primary BCS as the predominant etiology,earlier clinical presentation,and hence better treatment outcome.Underlying prothrombotic conditions play a key role in the etiopathogenesis of BCS,though work-up for the same is often unyielding in children.Use of next-generation sequencing in addition to conventional tests for thrombophilia leads to better diagnostic yield.In recent years,advances in radiological endovascular intervention techniques have revolutionized the treatment and outcome of BCS.Various non-invasive markers of fibrosis like liver and splenic stiffness measurement are being increasingly used to assess treatment response.Elastography techniques provide a novel non-invasive tool for measuring liver and splenic stiffness.This article reviews the diagnostic and therapeutic advances and challenges in children with BCS.

Finite element modeling and simulation of the implantation of braided stent to treat cerebral aneurysm

Braided stents were widely used to treat cerebral aneurysms and computational fluid dynamics(CFD)was used to evaluate the therapeutic effects.But the aneurysm-artery geometry used in CFD were usually undeformed which is inconsistent with clinical findings.Our team developed a finite element modeling workflow to simulate implantation of braided stents in patient-specific aneurysm-artery model.An LVIS-based braided stent was deployed into an aneurysm-artery model.The stent fully expanded,causing obvious deformation on the aneurysm-artery model.The workflow which we developed could provide reasonable deformed geometries of aneurysm-artery and braided stent for CFD computation and possibly assist surgical planning.