A novel procedure for medial axis reconstruction of vessels from Medical Imaging segmentation.

A procedure for reconstructing the central axis from diagnostic image processing is presented here, capable of solving the widespread problem of stepped shape effect that characterizes the most common algorithmic tools for processing the central axis for diagnostic imaging applications through the development of an algorithm correcting the spatial coordinates of each point belonging to the axis from the use of a common discrete image skeleton algorithm. The procedure is applied to the central axis traversing the vascular branch of the cerebral system, appropriately reconstructed from the processing of diagnostic images, using investigations of the local intensity values identified in adjacent voxels. The percentage intensity of the degree of adherence to a specific anatomical tissue acts as an attraction pole in the identification of the spatial center on which to place each point of the skeleton crossing the investigated anatomical structure. The results were shown in terms of the number of vessels identified overall compared to the original reference model. The procedure demonstrates high accuracy margin in the correction of the local coordinates of the central points that permits to allocate precise dimensional measurement of the anatomy under examination. The reconstruction of a central axis effectively centered in the region under examination represents a fundamental starting point in deducing, with a high margin of accuracy, key informations of a geometric and dimensional nature that favours the recognition of phenomena of shape alterations ascribable to the presence of clinical pathologies.

Ex vivo resection, vessel reconstruction and liver autotransplantation for cholangiocarcinoma: A report of two cases.

PURPOSE: Ex vivo liver resection and autotransplantation (ERAT) can be used to treat locally advanced tumors that are conventionally unresectable. Because the procedure is rare, there are very few reports in the literature. Recently, we performed ERAT for two cases of cholangiocarcinoma invading caudate lobe, the retrohepatic vena cava and hepatic veins, and investigated technical variations of this procedure. METHODS: One patient was a 57-year-old man with liver caudate lobe metastasis from cholangiocarcinoma after pancreaticoduodenal resection five years ago, and the other patient was a 68-year-old man with caudate lobe cholangiocarcinoma. Both cases were considered to be unresectable by conventional resection due to the critical invasion of the retrohepatic vena cava along with the three hepatic veins. Therefore, ERAT was indicated in these two cases. RESULTS: The liver along with the retrohepatic vena cava was removed, which was replaced by GORE-TEX synthetic artificial vessel grafts with angioplasty to reconstruct the inferior vena cava (IVC), and the GORE-TEX synthetic artificial vessel anastomosed to the right auricular appendage or the IVC to build the continuity of the IVC. Ex vivo caudate lobe hepatectomy was performed, along with the retrohepatic vena cava and hepatic veins, and subsequently the reconstruction outflow of hepatic venous was established using cold-preserved allogeneic vessels and falciform ligament. Finally, remnant of the liver was implanted by Piggyback liver transplantation. The hepatic vein, portal vein, hepatic artery and bile duct were anastomosed, and autotransplantation of the liver was completed. The patients were followed-up for 18 months and showed good liver function, with no recurrence of cancer. CONCLUSIONS: ERAT should be considered as a therapeutic option for selected patients with cholangiocarcinoma invading caudate lobe, the retrohepatic vena cava and hepatic veins. It is crucial to reconstruct the outflow of hepatic venous according to different situations.

[The first experience of small intestinal autotransplantation for advanced digestive cancer]. / Pervyi opyt autotransplantatsii tonkoi kishki pri mestno-rasprostranennykh opukholyakh zheludochno-kishechnogo trakta.

Usually, gastrointestinal tumors (GIT) invading great vessels are acknowledged to be irresectable. Along with that, we can expect positive oncological results only when there is combination treatment with radical surgery (R0 resection). In this article we share the first experience of small intestinal autotransplantation as a method of radical surgery in locally advanced GIT. We conducted the analysis of outcomes of three patients (with pancreas cancer (n=2) and neuroendocrine tumor of caecum (n=1), with neoplastic process involving to superior mesenteric artery and vein. We analyzed intraoperative aspects and algorithm of small intestinal autotransplantation. Long-term outcomes with 1.5-13 months of observing time are presented. On the basis of conducted analysis the authors suggest the possibility of small intestinal autotransplantation in referral centers with strict personalized approach and multidisciplinary surgical team.

State of the art review: The management of chronic vascular disorders in the hand and upper limb.

This review article summarizes the basic principles of vascular anatomy, physiology, diagnostic work-up and treatment for patients with nontraumatic upper extremity vascular disorders. Vascular disorders can be considered vasospastic or occlusive. The most commonly encountered vasospastic condition is Raynaud's Phenomenon secondary to scleroderma. While historically this has been managed medically with vasodilators, more advanced cases can benefit from surgical treatment to improve blood flow and minimize tissue loss, with compelling evidence that earlier surgical intervention can modify disease process and should be considered. Occlusive disease can present as aneurysm or thrombosis and often requires surgical treatment with resection of the occluded segment with or without vascular reconstruction. In advanced atherosclerotic disease or end stage ischemia, arterialization of the venous system can be considered to avoid more proximal amputations.

Total arch replacement with extended branched stented anastomosis frozen elephant trunk repair for type A dissection improves operative outcome.

Objective: Emergency surgical repair is the standard treatment for acute aortic dissection type A. However, the surgical risk of total arch replacement remains high. The Viabahn Open Revascularization TEChnique has been used for supra-aortic reconstruction during total arch replacement. This Cleveland Clinic technique is called "branched stented anastomosis frozen elephant trunk repair." Our total arch replacement with reconstructed extended branched stented anastomosis frozen elephant trunk repair requires no unnecessary cervical artery exposure. We compared the outcomes of extended branched stented anastomosis frozen elephant trunk repair and conventional total arch replacement in acute aortic dissection type A. Methods: We compared the clinical course of patients undergoing total arch replacement using sutureless direct branch vessel stent grafting with frozen elephant trunk (extended branched stented anastomosis frozen elephant trunk repair) for acute aortic dissection type A with patients undergoing conventional total arch replacement. For the procedure, the aortic arch was transected circumferentially distal to the brachiocephalic artery origin. Frozen elephant trunk was fenestrated by heating with a cautery, and the self-expandable stent graft was delivered into the branch vessels through the fenestration. Results: Of 58 cases, 21 and 37 were classified in the extended branched stented anastomosis frozen elephant trunk repair and conventional total arch replacement groups, respectively. The times (minutes) of selective antegrade cerebral perfusion (75 ± 24, 118 ± 47), total operation (313 ± 83, 470 ± 151), and cardiopulmonary bypass (195 ± 46, 277 ± 96) were significantly better in the extended branched stented anastomosis frozen elephant trunk repair group (P < .001). Six surgical deaths occurred: 2 (9%) in the extended branched stented anastomosis frozen elephant trunk repair group and 4 (10%) in the conventional total arch replacement group. In all cases, only 1 patient (2%) in the conventional total arch replacement group had a branch artery-related complication during the postoperative follow-up period. In the extended branched stented anastomosis frozen elephant trunk repair group, blood product use significantly decreased (P < .05). Conclusions: Extended branched stented anastomosis frozen elephant trunk repair has shown comparable safety and efficacy to conventional total arch replacement and can be used for acute aortic dissection type A emergency repair. It optimizes true lumen perfusion and facilitates supra-aortic artery remodeling.

Towards Autonomous Robotic Minimally Invasive Ultrasound Scanning and Vessel Reconstruction on Non-Planar Surfaces.

Autonomous robotic Ultrasound (US) scanning has been the subject of research for more than 2 decades. However, little work has been done to apply this concept into a minimally invasive setting, in which accurate force sensing is generally not available and robot kinematics are unreliable due to the tendon-driven, compliant robot structure. As a result, the adequate orientation of the probe towards the tissue surface remains unknown and the anatomy reconstructed from scan may become highly inaccurate. In this work we present solutions to both of these challenges: an attitude sensor fusion scheme for improved kinematic sensing and a visual, deep learning based algorithm to establish and maintain contact between the organ surface and the US probe. We further introduce a novel scheme to estimate and orient the probe perpendicular to the center line of a vascular structure. Our approach enables, for the first time, to autonomously scan across a non-planar surface and navigate along an anatomical structure with a robotically guided minimally invasive US probe. Our experiments on a vessel phantom with a convex surface confirm a significant improvement of the reconstructed curved vessel geometry, with our approach strongly reducing the mean positional error and variance. In the future, our approach could help identify vascular structures more effectively and help pave the way towards semi-autonomous assistance during partial hepatectomy and the potential to reduce procedure length and complication rates.

Chronic Mesenteric Ischemia: Differential Vascularsurgical Therapy and Its Outcome in a Single-Center Observational Study.

Aim: The aim of this study was to investigate short-/long-term vascularsurgical patency and the outcome in chronic mesenteric ischemia (CMI) depending on the mesenteric revascularization technique and reflecting real-world data. Methods: This retrospective single-center observational study registered all patients who had undergone open vascularsurgical reconstruction because of CMI at a tertiary German university hospital comparing 1-versus (vs.) 2-vessel as well as antegrade versus retrograde reconstructions. Results: In total, 35 patients were enrolled (mean [± SD] age, 64 ± 13 [range, 45-83] years; sex ratio [m:f], 16:19 [46:54]) over 12 years. Three patients with symptoms of mesenteric ischemia because of rare causes (radiation-induced and median arcuate ligament syndrome) have been excluded. While 51% of patients underwent 1-vessel reconstruction, 49% underwent 2-vessel reconstruction. There was a trend of (i) more perioperative complications in the 2-vessel group (88.2% vs. 55.6%, p = 0.06) and (ii) higher morbidity at 1 year in the 2-vessel versus 1-vessel group (57.1% and 42.9%, respectively; p = 0.466), while the morbidity of the 2-vessel versus 1-vessel group at 5 years (100% vs. 33.3%) was significantly different (p = 0.009). The mortality was greater in the 2-vessel versus 1-vessel group as it was significantly different in the early postoperative period (31.3% vs. 0, p = 0.016) and at 1 year (50% vs. 0, p = 0.005) and 5 years (100% vs. 11%, p = 0.003). Regarding overall survival, the 1-vessel group showed a significant superiority above the 2-vessel group (p = 0.004). Actually, there was no significant difference of early postoperative morbidity comparing the retrograde and antegrade group (p = 0.285) as well as at 1 year and 5 years (p = 0.715 and p = 0.620, respectively). In addition, there was no significantly different postoperative mortality in antegrade versus retrograde group at each time. Specific and general complication rates were 62.9% and 57.1%, respectively, resulting in an overall morbidity of 77.1% (mortality, 20%). Conclusion: The vascular surgeon should be prepared to perform various procedures of mesenteric reconstruction to tailor the operative strategy to the specific needs of the individual patient.

Fractional flow reserve for coronary stenosis assessment derived from fusion of intravascular ultrasound and X-ray angiography.

BACKGROUND: Intravascular ultrasound (IVUS) provides good insight into lumen boundary and plaques; however, it is still difficult to detect functionally significant stenosis from IVUS images for the guidance of coronary percutaneous intervention (PCI). This study aimed to develop a novel method to estimate fractional flow reserve (FFR) value for determining the functional significance of coronary artery disease through the fusion of IVUS and X-ray angiographic images. METHODS: We developed a novel approach to 3D vessel reconstruction by integrating IVUS with X-ray angiographic images. Based on the reconstructed geometry and the inlet flow derived from the thrombolysis in myocardial infarction (TIMI) frame count, a simplified fluid dynamics equation was established to compute the pressure drop and IVUS-derived FFR (AccuFFRivus) was subsequently obtained. To validate the feasibility and performance of this IVUS-based FFR method, we performed AccuFFRivus calculations on 32 coronary vessels with invasive FFR as the reference standard. RESULTS: Great correlation (r=0.86, P<0.001) was observed between AccuFFRivus and FFR. The area under the receiver-operating characteristic curve (AUC) was higher for AccuFFRivus than minimal lumen area (MLA, <4 mm2) and diameter stenosis rate (DS% ≥50%) [0.98 (95% CI: 0.86 to 1.0) vs. 0.78 (95% CI: 0.60 to 0.91) and 0.66 (95% CI: 0.47 to 0.82)]. Bland-Altman plot showed a mean difference value of -0.011 (limits of agreement: -0.156 to 0.134). CONCLUSIONS: AccuFFRivus is a novel method for hybridizing IVUS and X-ray angiographic images to identify functionally significant stenosis with FFR ≤0.80. The good diagnostic performance from the initial validation study demonstrates the potential for clinical utilization of physiologically guided decision-making. Further validation is required in future studies with a large number of cases.

Extended thymectomy with blood vessel resection and reconstruction improves therapeutic outcome for clinical stage III thymic carcinoma patients: a real-world research.

OBJECTIVES: We examine the therapeutic efficacy of extended thymectomy with blood vessel resection and reconstruction in thymic carcinoma patients with great vessel invasion. METHODS: In total 26 patients diagnosed as clinical stage III thymic carcinoma with severe great vessel invasion were enrolled in this retrospective study. Among these patients, 14 cases received adjuvant chemo- and radiotherapy (non-operation subgroup, NOG), the other 12 patients received extended thymectomy with vessel resection and reconstruction followed by the adjuvant treatment (operation subgroup, OG). RESULTS: All surgical procedures went smoothly with no perioperative death. R0 resection was obtained in all surgical cases, and we also observed a lymph node metastasis rate of 38.8%. The overall survival (OS) was 34 months for the whole cohort, 48 and 26 months for the OG and NOG respectively (p = 0.013). The median disease metastasis free survival (DMFS) was 47 months for the OG and 18 months for the NOG (p = 0.019). CONCLUSION: Extended thymectomy with vessel resection is feasible for patients with clinical stage III thymic carcinoma. Surgery significantly improves the overall survival and the prognosis of clinical stage III thymic carcinoma.

[Treatment of intracranial aneurysms with flow diverters]. / Einsatz von Flow-Divertern zur Behandlung intrakranieller Aneurysmen.

CLINICAL ISSUE: The clinical picture of a subarachnoid haemorrhage (SAH) is associated with a high morbidity and mortality, due to the associated complications. Therefore, both unruptured and ruptured aneurysms are to be treated based on an individual and interdisciplinary treatment concept. Several endovascular procedures are already available for the treatment of intracranial aneurysms. A more recent concept is the treatment with vessel-reconstructive stents so-called flow diverters. PRACTICAL RECOMMENDATIONS: Due to the continuous development and revision of flow diverters, the initial complication rates have been significantly reduced, which now effectively and efficiently justifies their clinical use. After careful patient selection and risk-benefit assessment, the implantation of a flow diverter can also be considered for the treatment of ruptured aneurysms and is often the only therapy option in such situations.

Role of Collateral Venous Circulation in Prevention of Sinistral Portal Hypertension After Superior Mesenteric-Portal Vein Confluence Resection during Pancreaticoduodenectomy: a Single-Center Experience.

BACKGROUND: The ligation of the splenic vein (SV) during pancreaticoduodenectomy (PD) may result in sinistral portal hypertension (SPH). This study aimed to identify the collateral pathways that formed postoperatively and evaluate the impact of omentum and arc of Barkow preservation in PD. METHODS: Patients who underwent PD between January 2013 and May 2018 at the Second Affiliated Hospital of Zhejiang University were enrolled in this retrospective study. PD was performed with preservation of the greater omentum and arc of Barkow. Venous collaterals, spleen size, and platelet count were evaluated before and after surgery. RESULTS: In total, 330 patients underwent PD, of whom, 43 patients who underwent superior mesenteric vein (SMV)/portal vein (PV) reconstruction and splenic vein (SV) ligation were selected. No patient developed severe gastrointestinal bleeding. Three collateral routes were identified: the left gastric route, the colic marginal route, and the first jejunal route. Seventeen patients developed splenomegaly. Twenty-three patients developed thrombocytopenia. However, none of them developed gastrointestinal bleeding or other clinical complaints. CONCLUSION: Although subclinical SPH developed after SV ligation, postoperative gastrointestinal bleeding was uncommon.

Pipeline-assisted coiling versus pipeline in flow diversion treatment of intracranial aneurysms.

BACKGROUND AND PURPOSE: Flow-diversion therapy (FDT) for large and complex intracranial aneurysms is effective and considered superior to primary coil embolization. Data evaluating common treatment with both FDT and coiling continues to emerge, but information on outcomes remains scarce. This study aims to examine further the efficiency and outcomes correlated with joint FDT using pipeline embolization device (PED) and coiling compared to PED-alone in treating intracranial aneurysms. MATERIALS AND METHODS: Comparative review and analysis of aneurysm treatment with PED in 416 subjects were conducted. Joint modality, PED, and coiling were compared to PED-alone for aneurysm occlusion, recurrence, retreatment, thromboembolic or hemorrhagic events, and functional outcome using the modified Rankin Scale. Data on patient demographics, aneurysm characteristics, clinical and angiographic follow up, were also collected. Both univariate analysis and multivariate logistic regression modeling using mixed-effects were performed. RESULTS: Total of 437 aneurysms were treated using PED of which 74 were managed with both PED and coiling. Average patient-age was 56 years, the majority were men (85%), an average aneurysm size was 9 mm, and the majority were saccular aneurysms (84%). Larger aneurysm size was associated with a poor outcome in patients with unruptured aneurysms (OR = 1.06). Adjusted regression analyses revealed no differences between treatment groups in thromboembolic or hemorrhagic events, aneurysm occlusion rate, residual flow on follow up angiography, or functional outcome. CONCLUSIONS: Treatment of intracranial aneurysms with joint PED and coiling was safe with no increase in complications when compared to PED alone. Aneurysm occlusion rates and functional outcome with PED and coiling stays comparable to treatment with PED-alone.

Reconstruction of mediastinal vessels for invasive thymoma: a retrospective analysis of 25 cases.

BACKGROUND: Discuss an appropriate strategy for treatment of invasive thymoma invading adjacent great vessels. METHODS: A retrospective study on 25 patients with invasive thymoma invading neighboring great vessels was performed. The corresponding data including clinical presentation, operation procedure, adjuvant radio-chemotherapy and follow-up were reviewed. RESULTS: Twenty of 25 (80%) patients with invasive thymoma underwent complete resection of the tumor along with vessel reconstruction. Intraoperatively, different types of operation were conducted, namely, brachiocephalic vein (BCV)-right atrial appendage (RAA) reconstruction in 11 cases, complex vessel reconstruction (more than one graft) in 1 case and superior vena cava (SVC)-SVC reconstruction in the remaining cases. Ringed polytetrafluoroethylene (PTFE) grafts were used for vessel reconstruction. Postoperatively, three cases suffered from pulmonary infection, and three cases had haemothorax, chylothorax and atelectasis, respectively. Two patients died due to acute respiratory distress syndrome within 90 days after the surgery. Within the remaining patients, 11 cases (44%) experienced a relapse and finally 8 (32%) patients died. Compared to R1 resection group, R0 resection group had a better prognosis (Log-rank P=0.0196). The 3- and 5-year survival rates were 79.6% and 59.1%, with median survival time of 84 months. CONCLUSIONS: Reconstruction of mediastinal vessels for invasive thymoma is a feasible technology method. Radical resection of the tumor with involved neighboring structures is the key to prolong overall survival for patients suffered from invasive thymoma.

Blood vessel modeling for interactive simulation of interventional neuroradiology procedures.

Endovascular interventions can benefit from interactive simulation in their training phase but also during pre-operative and intra-operative phases if simulation scenarios are based on patient data. A key feature in this context is the ability to extract, from patient images, models of blood vessels that impede neither the realism nor the performance of simulation. This paper addresses both the segmentation and reconstruction of the vasculature from 3D Rotational Angiography data, and adapted to simulation: An original tracking algorithm is proposed to segment the vessel tree while filtering points extracted at the vessel surface in the vicinity of each point on the centerline; then an automatic procedure is described to reconstruct each local unstructured point set as a skeleton-based implicit surface (blobby model). The output of successively applying both algorithms is a new model of vasculature as a tree of local implicit models. The segmentation algorithm is compared with Multiple Hypothesis Testing (MHT) algorithm (Friman et al., 2010) on patient data, showing its greater ability to track blood vessels. The reconstruction algorithm is evaluated on both synthetic and patient data and demonstrate its ability to fit points with a subvoxel precision. Various tests are also reported where our model is used to simulate catheter navigation in interventional neuroradiology. An excellent realism, and much lower computational costs are reported when compared to triangular mesh surface models.

LIVER WHOLE SLIDE IMAGE ANALYSIS FOR 3D VESSEL RECONSTRUCTION.

The emergence of digital pathology has enabled numerous quantitative analyses of histopathology structures. However, most pathology image analyses are limited to two-dimensional datasets, resulting in substantial information loss and incomplete interpretation. To address this, we have developed a complete framework for three-dimensional whole slide image analysis and demonstrated its efficacy on 3D vessel structure analysis with liver tissue sections. The proposed workflow includes components on image registration, vessel segmentation, vessel cross-section association, object interpolation, and volumetric rendering. For 3D vessel reconstruction, a cost function is formulated based on shape descriptors, spatial similarity and trajectory smoothness by taking into account four vessel association scenarios. An efficient entropy-based Relaxed Integer Programming (eRIP) method is proposed to identify the optimal inter-frame vessel associations. The reconstructed 3D vessels are both quantitatively and qualitatively validated. Evaluation results demonstrate high efficiency and accuracy of the proposed method, suggesting its promise to support further 3D vessel analysis with whole slide images.

Algorithms for improved 3-D reconstruction of live mammalian embryo vasculature from optical coherence tomography data.

BACKGROUND: Robust reconstructions of the three-dimensional network of blood vessels in developing embryos imaged by optical coherence tomography (OCT) are needed for quantifying the longitudinal development of vascular networks in live mammalian embryos, in support of developmental cardiovascular research. Past computational methods [such as speckle variance (SV)] have demonstrated the feasibility of vascular reconstruction, but multiple challenges remain including: the presence of vessel structures at multiple spatial scales, thin blood vessels with weak flow, and artifacts resulting from bulk tissue motion (BTM). METHODS: In order to overcome these challenges, this paper introduces a robust and scalable reconstruction algorithm based on a combination of anomaly detection algorithms and a parametric dictionary based sparse representation of blood vessels from structural OCT data. RESULTS: Validation results using confocal data as the baseline demonstrate that the proposed method enables the detection of vessel segments that are either partially missed or weakly reconstructed using the SV method. Finally, quantitative measurements of vessel reconstruction quality indicate an overall higher quality of vessel reconstruction with the proposed method. CONCLUSIONS: Results suggest that sparsity-integrated speckle anomaly detection (SSAD) is potentially a valuable tool for performing accurate quantification of the progression of vascular development in the mammalian embryonic yolk sac as imaged using OCT.

Segment-orientated anatomical liver resection for the treatment of hepatic alveolar echinococcosis in the middle lobe of the liver / 中华消化外科杂志

Objective To investigate the efficacy and feasibility of segment-orientated anatomical liver resection for the treatment of hepatic alveolar echinococcosis (HAE) in the middle lobe of the liver.Methods The clinical data of a female patient with HAE in the middle lobe of the liver who was admitted to the First Affiliated Hospital of Xi'an Jiaotong University in September 2013 were retrospectively analyzed.Before operation,various surgical plannings were facilitated by a three-dimensional reconstruction system,and then the surgical planning was determined with the assistance of the multivariate analysis (volume measurement of liver,resectability of remnant functional liver,evaluation of vascular resection and reconstruction,Child-Pugh score and indocyanine green retention at 15 minutes).Segment-orientated anatomical liver resection(segment Ⅴ,Ⅷ and Ⅳb) was performed on the patient.There was a close relationship between the HAE and the first and the second hepatic portal during operation,and the anatomical liver resection of segment Ⅴ,Ⅷ and Ⅳb was precisely carried out.The patient was followed up by outpatient examination and telephone interview every month up to April 2014.The condition of the liver was observed by B ultrasound and computed tomography examinations.Results The three-dimensional reconstruction of the CT data of the patient clearly displayed the anatomical structure and adjacent relationship between the tumor,abdominal organs and major abdominal vessels.The preoperative evaluation of the anatomy of tumor based on three-dimensional images was confirmed with operative findings.The operation time and volume of blood loss were 410 minutes and 1 000 mL,respectively.The patient did not receive blood transfusion.The intraoperative vital signs of the patient were stable.There were no complications such as hepatic insufficiency.The duration of postoperative hospital stay was 15 days.Surgical incision was healed at discharge.The results of blood routine and blood biochemistry test,daily diet and basic self-care ability were in normal condition.HAE was diagnosed based on the result of pathological examination.Albendazole was administered with 1 200 mg/d after operation.The patient was followed up for 6 months and returned to work.The weight of the patient increased by 5 kilograms than that at discharge,without complaint of discomfort.There was no recurrence of HAE and hepatic echinococcosis of organs.Conclusions Segment-orientated anatomical liver resection is not only a method for complete resection,but also maximizes the functional remnant of liver on the basis of intraoperative three-dimensional reconstruction system together with selective hepatic inflow occlusion and vessel reconstruction technique.The patient gets a full recovery with satisfactory outcome.

Three-dimensional reconstruction of rabbit eye vessels based on X-ray phase contrast imaging technique / 医用生物力学

Objective To establish a three-dimensional (3D) visualization model for the vessel system of rabbit eyes using X-ray phase contrast imaging（XPCI）technique, and observe the morphological characteristics of iris vessels of the rabbit eyes. Methods Angiography on vessels of the New Zealand rabbit eyes was conducted using Barium sulfate as the contrast medium. The projected images of in vitro rabbit eye samples with high precision were obtained by XPCI technique, and then converted to tomography images by filter back projection. The 3D reconstruction of the rabbit eyes was completed by commercial visualization software Amira 5.2.2. Results The main blood vessels of the rabbit eyes were clear and coherent in the projection images, and the distribution and trend of some small vessels could be observed, with the smallest distinguishable blood vessel diameter being about 10 μm. The 3D model for vessel network of the rabbit eyes was built after 3D reconstruction of CT scan images. The major arterial circle of the iris could be observed at level 4 branch structure of vessels in the fundus, and the minimum diameter of vessels that could be identified was 40 μm. Conclusions The vessels of the rabbit eyes can be clearly observed and 3D visualization of vessel network can be constructed by using XPCI technique, which would provide basis for the analysis on hemodynamics of blood vessels in the eye and reference for the clinical study of glaucoma.

Surgical treatment for patients with chest cancers invading the superior vena cava / 中国医师进修杂志

Objective To summarize the experiences in clinical diagnosis and surgical treatment of chest cancers invading the superior vena cava (SVC). Method Retrospective study of 12 cases with chest cancers invading the SVC, SVC and innominate vein were reconstructed with prosthesis in 3 cases, the side wall of the SVC was excised and repaired in 9 cases. Results Complete resection was performed in 10cases,2 cases had incomplete resection. There was no death associated with operation in these patients. All patients were followed up for 1 - 7 years after operation,and 3 cases were lost to follow up,5 of remaining 9cases were dead because of relapse and metastasis, their median survival time was 8 months,other 4 cases lived, their median survival time was 42 months. Conclusions Patients with chest cancers invading the SVC should have surgical treatment of not only tumor resection but also the vessel reconstruction,the prognosis would be better than without surgical treatment. These patients have a high quality of life and live with long-term survival.

Limb conservation in extremity soft tissue sarcomas with vascular involvement.

BACKGROUND: The major neurovascular involvement and large primary tumors are indication of amputation. The present study is an attempt to explore the feasibility of a limb salvage surgery in extremity sarcoma cases with major vessel involvement. Oncological outcomes and surgery-related morbidities are compared with those reported in literature. MATERIALS AND METHODS: A retrospective review of all limb salvage surgeries done in our department between 2005 and 2008 was done and four cases of extremity sarcoma of lower limb involving femoral vessels analyzed. Interpretation of data from these cases, along with review of literature, is done. RESULTS: In all these cases a wide monobloc excision was done adhering to oncological principles. This required resection of superficial femoral artery alone in two cases, resection of superficial femoral artery along with common femoral vein and femoral nerve in another, and of common femoral vein alone in yet another. Reconstruction was done in all these cases with reversed long saphenous vein graft. Histopathology of resected margins was free of tumor in all the four patients. One patient developed local recurrence and one developed distant metastsis. Two were disease free for one year with good functional limb, one has been disease-free for three years and another was disease-free at two years, after which he defaulted further follow-up. One patient developed arterial blowout which required ligation of common femoral artery which resulted in gangrene of the limb. He underwent amputation. CONCLUSION: Major neurovascular involvement in extremity sarcoma is not considered a contraindication for limb salvage surgery. Review of literature also supports our view. Post-operative wound related complications are more in this group of patients. However, long term functional outcome is good. Literature suggests a good long term local control after vascular resection and reconstruction.