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1.
Sensors (Basel) ; 24(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732790

RESUMO

With the development of biometric identification technology, finger vein identification has received more and more widespread attention for its security, efficiency, and stability. However, because of the performance of the current standard finger vein image acquisition device and the complex internal organization of the finger, the acquired images are often heavily degraded and have lost their texture characteristics. This makes the topology of the finger veins inconspicuous or even difficult to distinguish, greatly affecting the identification accuracy. Therefore, this paper proposes a finger vein image recovery and enhancement algorithm using atmospheric scattering theory. Firstly, to normalize the local over-bright and over-dark regions of finger vein images within a certain threshold, the Gamma transform method is improved in this paper to correct and measure the gray value of a given image. Then, we reconstruct the image based on atmospheric scattering theory and design a pixel mutation filter to segment the venous and non-venous contact zones. Finally, the degraded finger vein images are recovered and enhanced by global image gray value normalization. Experiments on SDUMLA-HMT and ZJ-UVM datasets show that our proposed method effectively achieves the recovery and enhancement of degraded finger vein images. The image restoration and enhancement algorithm proposed in this paper performs well in finger vein recognition using traditional methods, machine learning, and deep learning. The recognition accuracy of the processed image is improved by more than 10% compared to the original image.


Assuntos
Algoritmos , Dedos , Processamento de Imagem Assistida por Computador , Veias , Humanos , Dedos/irrigação sanguínea , Dedos/diagnóstico por imagem , Veias/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Identificação Biométrica/métodos , Atmosfera
2.
J Clin Hypertens (Greenwich) ; 26(5): 584-587, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38605571

RESUMO

In patients with primary hyperaldosteronism (PA), adrenal vein sampling (AVS) can identify patients suitable for unilateral adrenalectomy. However, in AVS with an indeterminate aldosterone-to-cortisol lateralization (ACL) ratio of 3.0-4.0, clinical guidance is unclear. The authors screened all patients undergoing AVS at the Cleveland Clinic from October 2010 to January 2021 and identified 18 patients with indeterminate ACL results. Ten underwent adrenalectomy and eight continued medical management. The surgical group was younger (58.5 vs. 68 years, p = .17), and more likely to have a unilateral imaging adrenal abnormality (90% vs. 38%, p = .043) and a lower contralateral suppression index (0.63 vs. 1.1, p = .14). Post-treatment, the surgical group had a significant reduction in diastolic blood pressure (-5.5 mmHg, p = .043) and aldosterone (4.40 vs. 35.80 ng/mL, p = .035) and required fewer anti-hypertensive medications (2 vs. 3, p = .015). These findings may support the benefit of adrenalectomy in a select group of patients with indeterminate ACL.


Assuntos
Glândulas Suprarrenais , Adrenalectomia , Aldosterona , Hidrocortisona , Hiperaldosteronismo , Humanos , Hiperaldosteronismo/cirurgia , Hiperaldosteronismo/sangue , Hiperaldosteronismo/diagnóstico , Pessoa de Meia-Idade , Feminino , Adrenalectomia/métodos , Masculino , Glândulas Suprarrenais/irrigação sanguínea , Glândulas Suprarrenais/cirurgia , Aldosterona/sangue , Idoso , Hidrocortisona/sangue , Anti-Hipertensivos/uso terapêutico , Estudos Retrospectivos , Veias/cirurgia , Pressão Sanguínea/fisiologia , Hipertensão/diagnóstico , Hipertensão/cirurgia , Ohio/epidemiologia , Resultado do Tratamento
3.
Langenbecks Arch Surg ; 409(1): 122, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607450

RESUMO

PURPOSE: Pancreatic ductal adenocarcinoma (PADC) still has nowadays a very impaired long-term survival. Most studies are focused on overall survival; however, local recurrence occurs about up to 50% of cases and seems to be highly related with margin resection status. We aim to analyze the impact of vascular resection margins on local recurrence (LR) and to assess its impact on overall and disease-free survival. METHODS: Eighty out of 191 patients who underwent pancreatoduodenectomy in a university hospital between 2006 and 2021 with PDAC diagnosis were analyzed and vascular margin status specifically addressed. Univariate and multivariate were performed. Time to LR was compared by using the Kaplan-Meier method and prognostic factors assessed using Cox regression hazards model. RESULTS: LR appeared in 10 (50%) of the overall R1 resections in the venous margin and 9 (60%) in the arterial one. Time to LR was significantly shorter when any margin was overall affected (23.2 vs 44.7 months, p = 0.01) and specifically in the arterial margin involvement (13.7 vs 32.1 months, p = 0.009). Overall R1 resections (HR 2.61, p = 0.013) and a positive arterial margin (HR 2.84, p = 0.012) were associated with local recurrence on univariate analysis, whereas arterial positive margin remained significant on multivariate analysis (HR 2.70, p = 0.031). CONCLUSIONS: Arterial margin invasion is correlated in our cohort with local recurrence. Given the limited ability to modify this margin intraoperatively, preoperative therapies should be considered to improve local margin clearance.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Adenocarcinoma/cirurgia , Pancreaticoduodenectomia , Neoplasias Pancreáticas/cirurgia , Artérias , Veias , Margens de Excisão
4.
Radiographics ; 44(5): e230115, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38662586

RESUMO

Adrenal vein sampling (AVS) is the standard method for distinguishing unilateral from bilateral sources of autonomous aldosterone production in patients with primary aldosteronism. This procedure has been performed at limited specialized centers due to its technical complexity. With recent advances in imaging technology and knowledge of adrenal vein anatomy in parallel with the development of adjunctive techniques, AVS has become easier to perform, even at nonspecialized centers. Although rare, anatomic variants of the adrenal veins can cause sampling failure or misinterpretation of the sampling results. The inferior accessory hepatic vein and the inferior emissary vein are useful anatomic landmarks for right adrenal vein cannulation, which is the most difficult and crucial step in AVS. Meticulous assessment of adrenal vein anatomy on multidetector CT images and the use of a catheter suitable for the anatomy are crucial for adrenal vein cannulation. Adjunctive techniques such as intraprocedural cortisol assay, cone-beam CT, and coaxial guidewire-catheter techniques are useful tools to confirm right adrenal vein cannulation or to troubleshoot difficult blood sampling. Interventional radiologists should be involved in interpreting the sampling results because technical factors may affect the results. In rare instances, bilateral adrenal suppression, in which aldosterone-to-cortisol ratios of both adrenal glands are lower than that of the inferior vena cava, can be encountered. Repeat sampling may be necessary in this situation. Collaboration with endocrinology and laboratory medicine services is of great importance to optimize the quality of the samples and for smooth and successful operation. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.


Assuntos
Glândulas Suprarrenais , Hiperaldosteronismo , Humanos , Glândulas Suprarrenais/irrigação sanguínea , Glândulas Suprarrenais/diagnóstico por imagem , Hiperaldosteronismo/diagnóstico por imagem , Veias/diagnóstico por imagem , Aldosterona/sangue , Veias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada Multidetectores/métodos , Pontos de Referência Anatômicos , Radiografia Intervencionista/métodos
5.
Nat Commun ; 15(1): 3118, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600061

RESUMO

Formation of organo-typical vascular networks requires cross-talk between differentiating parenchymal cells and developing blood vessels. Here we identify a Vegfa driven venous sprouting process involving parenchymal to vein cross-talk regulating venous endothelial Vegfa signaling strength and subsequent formation of a specialized angiogenic cell, prefabricated with an intact lumen and pericyte coverage, termed L-Tip cell. L-Tip cell selection in the venous domain requires genetic interaction between vascular Aplnra and Kdrl in a subset of venous endothelial cells and exposure to parenchymal derived Vegfa and Apelin. Parenchymal Esm1 controls the spatial positioning of venous sprouting by fine-tuning local Vegfa availability. These findings may provide a conceptual framework for understanding how Vegfa generates organo-typical vascular networks based on the selection of competent endothelial cells, induced via spatio-temporal control of endothelial Kdrl signaling strength involving multiple parenchymal derived cues generated in a tissue dependent metabolic context.


Assuntos
Angiogênese , Células Endoteliais , Neovascularização Fisiológica , Células Endoteliais/metabolismo , Neovascularização Fisiológica/genética , Veias
6.
Microsurgery ; 44(4): e31179, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38676605

RESUMO

BACKGROUND: The profunda artery perforator (PAP) flap has gained popularity as a reliable alternative in breast reconstruction. Extensive research has focused on its vascular supply, dissection techniques, and broader applications beyond breast reconstruction. This study aims to investigate the correlation between the number of veins anastomosed for the PAP flap and postoperative complications. METHODS: A retrospective study was conducted to evaluate the outcomes of breast reconstructions with PAP flaps at our institution between 2018 and 2022. A total of 103 PAP flaps in 88 patients were included. Statistical analysis was performed to compare outcomes between flaps with one vein anastomosis and those with two vein anastomoses. Patient characteristics, intra and postoperative parameters were analysed. RESULTS: One vein anastomosis was used in 36 flaps (35.0%), whereas two vein anastomoses were used in 67 flaps (65.0%). No significant differences were found in patient characteristics between the one vein and two vein groups. The comparison of ischemia times between flaps with one versus two veins revealed no statistically significant difference, with mean ischemia times of 56.2 ± 36.8 min and 58.7 ± 33.0 min, respectively. Regarding outcomes, there were no statistically significant differences in secondary lipofilling, revision of vein anastomosis, or total flap loss between the two groups. Fat necrosis was observed in 5 (13.9%) one vein flaps and 5 (7.5%) two vein flaps, indicating no statistically significant difference between the two groups (p = .313). In the one vein group, the most frequently employed coupler ring had a diameter of 2.5 mm. In the two vein group, the most prevalent combination consisted of a 2.0 mm diameter with a 2.5 mm diameter. CONCLUSION: Based on our study results, both one vein anastomosis and two vein anastomoses are viable options for breast reconstruction with PAP flap. The utilization of either one or two veins did not significantly affect ischemia time or flap loss. Fat necrosis exhibited a higher incidence in the single-vein group; however, this difference was also not statistically significant. These findings underscore the effectiveness of both approaches, providing surgeons with flexibility in tailoring their surgical techniques based on patient-specific considerations and anatomical factors.


Assuntos
Anastomose Cirúrgica , Mamoplastia , Retalho Perfurante , Complicações Pós-Operatórias , Veias , Humanos , Mamoplastia/métodos , Feminino , Retalho Perfurante/irrigação sanguínea , Estudos Retrospectivos , Pessoa de Meia-Idade , Anastomose Cirúrgica/métodos , Adulto , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Veias/cirurgia , Neoplasias da Mama/cirurgia , Idoso
7.
Vasc Health Risk Manag ; 20: 177-181, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38623542

RESUMO

Cerebral sinovenous thrombosis (CSVT) encompasses a spectrum of disorders involving thrombosis of the cerebral venous system. As shown by previous epidemiological studies, the prevalence of cerebral sinovenous thrombosis is 4-7 cases per million people. Nephrotic syndrome was very rarely associated with thrombosis cerebral veins or sinuses. Hypercoagulability and thrombotic complications in nephrotic syndrome are most commonly seen in deep veins of the lower extremities and renal veins. Our case highlights a unique scenario in which cerebral sinovenous thrombosis was the initial presentation of nephrotic syndrome in a patient that was not an important past medical or surgical problem. The patient was brought to the emergency department with severe headache, vomiting, altered mental status, and generalized body swelling. Laboratory results showed proteinuria, hypoalbuminemia and hyperlipidemia. Non-contrast brain CT demonstrated hemorrhagic venous infarct associated with vasogenic edema. A subsequent brain MR venogram demonstrated occlusion of superior sagittal and right transverse sinuses. She was managed with low molecular weight heparin and intervenous corticosteroids then shifted to rivaroxaban and oral steroids, respectively, which resulted in massive clinical improvement and resolution of thrombus.


Assuntos
Síndrome Nefrótica , Trombose dos Seios Intracranianos , Trombose , Feminino , Humanos , Síndrome Nefrótica/complicações , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/tratamento farmacológico , Encéfalo , Veias , Trombose dos Seios Intracranianos/complicações , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/tratamento farmacológico
8.
J Nepal Health Res Counc ; 21(4): 587-592, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38616587

RESUMO

BACKGROUND: Although rare, deep vein thrombosis is a potentially life-threatening complication of knee arthroscopy. There are scanty literature analysing deep vein thrombosis after arthroscopy in Nepal. This study aimed to identify the prevalence of deep vein thrombosis in patients undergoing knee arthroscopy without chemoprophylaxis postoperatively at 2 weeks and 6 weeks, respectively. The study also aimed to estimate the risk of deep vein thrombosis in these patients by using Caprini Risk Assessment Model. METHODS: This prospective observational study was conducted at AKB center, B and B Hospital, Gwarko, Lalitpur, over a period of 16 months. All patients who underwent arthroscopy knee surgeries fulfilling the inclusion criteria were included in the study. The primary outcome measure was the prevalence of deep vein thrombosis as diagnosed by compression color-coded ultrasonography of the popliteal vein and calf vein at 2 weeks and 6 weeks postoperatively. The secondary outcome measure was the prevalence of deep vein thrombosis in the risk groups according to Caprini Risk Assessment Model. RESULTS: Out of 612 patients who underwent arthroscopic knee surgeries during the study period, 2 patients (0.33%) developed deep vein thrombosis at 6 weeks follow-up as diagnosed with ultrasonography of the popliteal and calf veins. The prevalence rate in high-risk group was 0.33% (1 in 307) and in very high-risk group was 5.88% (1 in 17). CONCLUSIONS: There was a low prevalence of deep vein thrombosis without chemoprophylaxis following knee arthroscopy in our study. There was higher prevalence of deep vein thrombosis in very high-risk group patients, so close monitoring of such patients during follow-up is recommended.


Assuntos
Tromboembolia Venosa , Trombose Venosa , Humanos , Artroscopia/efeitos adversos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Nepal/epidemiologia , Veias , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia , Trombose Venosa/prevenção & controle
9.
Asian J Endosc Surg ; 17(3): e13311, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38622753

RESUMO

We present a rare case involving a 54-year-old man with a history of pancreatitis who developed a retroperitoneal lumbar vein aneurysm that was initially misidentified as a pancreatic pseudocyst. Subsequent imaging revealed an enlarged mass and retroperitoneal perforation. Despite initial hesitation, the patient eventually underwent radical surgery that enabled the successful removal of the mass, which was near the inferior vena cava. Pathological examination confirmed varicose veins, and the final diagnosis was lumbar vein aneurysm in the retroperitoneum. The patient's postoperative recovery was uneventful, with no symptoms or recurrence observed on 6-month follow-up imaging. We investigated a potential link between pancreatitis and recurrent bleeding due to weakened venous walls. The findings from this case underscore the rarity of venous aneurysms and the diagnostic and treatment challenges due to the limited number of cases; furthermore, they emphasize that surgery should be carefully considered based on the lesion location and associated risks.


Assuntos
Aneurisma , Pancreatite , Masculino , Humanos , Pessoa de Meia-Idade , Veia Cava Inferior/cirurgia , Vértebras Lombares , Aneurisma/diagnóstico por imagem , Aneurisma/cirurgia , Veias
10.
PLoS One ; 19(4): e0301030, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38564498

RESUMO

We investigated the wing vein network topology in fruit flies and observed that the posterior cross vein (PCV) disrupts the symmetry of the entire network. The fluidic engineering function of this vein's disposition remains unexplored although the wing vein network is known to transport blood. We examined the fluid mechanical effects of the PCV's disposition on this blood-transporting network through numerical simulations involving the removal and rearrangement of the vein, avoiding impractical physical manipulation. We characterised the geometry of each wing membrane cell, a portion of the wing membrane surrounded by a group of veins, by determining the ratio of its surface area to the contact area with the veins. We considered this ratio in association with the flow velocities of seeping water from the blood within the veins to the membrane and evaporating water from the membrane, based on the mass conservation law. We observed that the division of a membrane cell by the PCV maximises the ratio of the areas in the divided cell on the wing-tip side by virtually shifting this vein's connections in our geometric membrane model. We derived blood flow rate and pressure loss within the venous network from their geometry, using an analogy of the venous network with a circuit consisting of hydraulic resistors based on Kirchhoff and Ohm's laws. The overall pressure loss in the network decreased by 20% with the presence of the PCV functioning as a paralleled hydraulic resistor. By contrast, any other cross-vein computationally arranged on another membrane cell as the PCV's substitution did not exhibit a larger reduction in the pressure loss. Overall, our numerical analyses, leveraging geometry and a circuit analogy, highlighted the effects of the PCV's presence and position on the blood-transporting vein network.


Assuntos
Hemodinâmica , Veias , Animais , Drosophila , Água
11.
Ann Plast Surg ; 92(4S Suppl 2): S132-S135, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556661

RESUMO

INTRODUCTION: Vascular malformations (VMs) typically appear at birth and grow commensurately with patients. They can vary broadly in vessel type and tissue involvement, and upper extremity (UE) VMs can pose unique functional and aesthetic challenges in children. Given the advent of operative and nonoperative technologies like sclerotherapy and medications, a contemporary review of the surgical management of UE VMs is warranted. METHODS: We performed a retrospective review of all patients who had surgical management of VMs from 2010 to 2021 at The Children's Hospital of Philadelphia. Demographics, lesion characteristics, treatment (including preceding nonsurgical therapies), complications, and final outcomes were recorded. Operative notes were reviewed for date of operation, depth of excision, type of closure, and current procedural terminology code. RESULTS: Sixty-seven patients with 88 procedures were studied. Average patient age was 5.8 years, with 64% White and 67% male. Venous (34%) and lymphatic (19%) malformations were most common, and anatomic locations were most frequently on the hand (33%) and forearm (25%). The average lesion diameter was 4.2 cm, although this varied by location (eg, 2.9 cm, hand; 11.1 cm, chest wall). Fifty-eight patients (87%) underwent surgical excision as their index procedure, and 9 had sclerotherapy before surgery. Thirty-nine patients (60%) had subcutaneous excisions, and the remainder required subfascial or intramuscular excisions. Nearly all excisions were closed primarily (97%). Of the 53 patients with documented follow-up, 32 patients (60%) had complete resolution of their lesion as of their final visit. Thirty of these 32 patients with no clinical evidence of residual VM had only 1 surgery for excision. CONCLUSION: Upper extremity VMs were composed of diverse conditions with varying vessel types, size, depth, and anatomic sites. Surgical excision of VMs of the UE was safe and effective. A majority of VMs were fully excised after 1 procedure and frequently closed primarily with relatively low complication rates. Future work should investigate decision-making and outcomes of all treatment options of VMs of the UE for optimal functionality and aesthetics.


Assuntos
Malformações Vasculares , Veias , Criança , Recém-Nascido , Humanos , Masculino , Pré-Escolar , Feminino , Estudos Retrospectivos , Veias/cirurgia , Malformações Vasculares/cirurgia , Escleroterapia/métodos , Mãos , Resultado do Tratamento
12.
J Chin Med Assoc ; 87(5): 455-462, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517403

RESUMO

Lymphedema impairs patients' function and quality of life. Currently, supermicrosurgical lymphovenous anastomosis (LVA) is regarded as a significant and effective treatment for lymphedema. This article aims to review recent literature on this procedure, serving as a reference for future research and surgical advancements. Evolving since the last century, LVA has emerged as a pivotal domain within modern microsurgery. It plays a crucial role in treating lymphatic disorders. Recent literature discusses clinical imaging, surgical techniques, postoperative care, and efficacy. Combining advanced tools, precise imaging, and surgical skills, LVA provides a safer and more effective treatment option for lymphedema patients, significantly enhancing their quality of life. This procedure also presents new challenges and opportunities in the realm of microsurgery.


Assuntos
Anastomose Cirúrgica , Vasos Linfáticos , Linfedema , Microcirurgia , Humanos , Anastomose Cirúrgica/métodos , Linfedema/cirurgia , Microcirurgia/métodos , Vasos Linfáticos/cirurgia , Veias/cirurgia
13.
J Hypertens ; 42(6): 1019-1026, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38527056

RESUMO

OBJECTIVE: Adrenal venous sampling (AVS) is key for primary aldosteronism subtype identification. However, the value of adrenocorticotropic hormone (ACTH) stimulation in AVS is still controversial. METHODS: In this prospective study, we investigated the role of continuous ACTH infusion on the performance and interpretation of bilateral simultaneous AVS using a standard protocol in 59 primary aldosteronism patients. We analyzed the selectivity index and lateralization index in AVS pre and post-ACTH and estimated the prognosis of patients who underwent adrenalectomy with different cutoff points of lateralization index post-ACTH. RESULTS: The confirmed success rate of bilateral adrenal vein catheterization increased from 84% pre-ACTH to 95% post-ACTH. Fifty percent of the patients had a decline in lateralization index post-ACTH, 30% of patients showed unilateral primary aldosteronism pre-ACTH but bilateral primary aldosteronism post-ACTH according to lateralization index at least 2 pre-ACTH and lateralization index at least 4 post-ACTH. The outcomes of the patients with primary aldosteronism after adrenalectomy indicated that all patients achieved clinical and biochemical success regardless of lateralization index at least 4 or less than 4 post-ACTH. Receiver operating characteristic curves showed that lateralization index cutoff 2.58 post-ACTH stimulation yielded the best threshold in lateralization with a sensitivity of 73.1% and a specificity of 92.9%. CONCLUSION: ACTH stimulation increased the AVS success rates in patients with primary aldosteronism, reduced lateralization index in some cases and decreased the proportion of identified unilateral primary aldosteronism, resulting in some patients losing the opportunity for disease cure. Compared with lateralization index at least 4, a lower cutoff point of lateralization index at least 2.58 after ACTH stimulation has better accuracy of lateralization diagnosis.


Assuntos
Glândulas Suprarrenais , Hormônio Adrenocorticotrópico , Hiperaldosteronismo , Humanos , Hiperaldosteronismo/sangue , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/cirurgia , Hiperaldosteronismo/classificação , Hormônio Adrenocorticotrópico/sangue , Feminino , Masculino , Estudos Prospectivos , Pessoa de Meia-Idade , Glândulas Suprarrenais/irrigação sanguínea , Adulto , Veias , Adrenalectomia , Aldosterona/sangue
14.
World J Surg ; 48(4): 978-988, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38502051

RESUMO

BACKGROUND: Inferior vena cava (IVC) resection is essential for complete (R0) excision of some malignancies. However, the optimal material for IVC reconstruction remains unclear. Our objective is to demonstrate the efficacy, safety, and advantages of using Non-Fascial Autologous Peritoneum (NFAP) for IVC reconstruction. To conduct a literature review of surgical strategies for tumors involving the IVC. METHODS: We reviewed all IVC reconstructions performed at our institution between 2015 and 2023. Preoperative, operative, postoperative, and follow-up data were collected and analyzed. RESULTS: A total of 33 consecutive IVC reconstructions were identified: seven direct sutures, eight venous homografts (VH), and 18 NFAP. With regard to NFAP, eight tubular (mean length, 12.5 cm) and 10 patch (mean length, 7.9 cm) IVC reconstructions were performed. Resection was R0 in 89% of the cases. Two patients had Clavien-Dindo grade I complications, 2 grade II, 2 grade III and 2 grade V complications. The only graft-related complication was a case of early partial thrombosis, which was conservatively treated. At a mean follow-up of 25.9 months, graft patency was 100%. There were seven recurrences and six deaths. Mean overall survival (OS) was 23.4 months and mean disease-free survival (DFS) was 14.4 months. According to our results, no statistically significant differences were found between NFAP and VH. CONCLUSIONS: NFAP is a safe and effective alternative for partial or complete IVC reconstruction and has many advantages over other techniques, including its lack of cost, wide and ready availability, extreme handiness, and versatility. Further comparative studies are required to determine the optimal technique for IVC reconstruction.


Assuntos
Peritônio , Pirenos , Veia Cava Inferior , Humanos , Veia Cava Inferior/cirurgia , Veia Cava Inferior/patologia , Peritônio/cirurgia , Estudos Retrospectivos , Veias , Resultado do Tratamento
15.
Sensors (Basel) ; 24(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38544143

RESUMO

How to obtain internal cavity features and perform image matching is a great challenge for laparoscopic 3D reconstruction. This paper proposes a method for detecting and associating vascular features based on dual-branch weighted fusion vascular structure enhancement. Our proposed method is divided into three stages, including analyzing various types of minimally invasive surgery (MIS) images and designing a universal preprocessing framework to make our method generalized. We propose a Gaussian weighted fusion vascular structure enhancement algorithm using the dual-branch Frangi measure and MFAT (multiscale fractional anisotropic tensor) to address the structural measurement differences and uneven responses between venous vessels and microvessels, providing effective structural information for vascular feature extraction. We extract vascular features through dual-circle detection based on branch point characteristics, and introduce NMS (non-maximum suppression) to reduce feature point redundancy. We also calculate the ZSSD (zero sum of squared differences) and perform feature matching on the neighboring blocks of feature points extracted from the front and back frames. The experimental results show that the proposed method has an average accuracy and repeatability score of 0.7149 and 0.5612 in the Vivo data set, respectively. By evaluating the quantity, repeatability, and accuracy of feature detection, our method has more advantages and robustness than the existing methods.


Assuntos
Algoritmos , Laparoscopia , Procedimentos Cirúrgicos Minimamente Invasivos , Veias , Microvasos
16.
J Physiol Sci ; 74(1): 21, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555424

RESUMO

Mean circulatory filling pressure, venous return curve, and Guyton's graphical analysis are basic concepts in cardiovascular physiology. However, some medical students may not know how to view and interpret or understand them adequately. To deepen students' understanding of the graphical analysis, in place of having to perform live animal experiments, we developed an interactive cardiovascular simulator, as a self-learning tool, as a web application. The minimum closed-loop model consisted of a ventricle, an artery, resistance, and a vein, excluding venous resistance. The simulator consists of three modules: setting (parameters and simulation modes), calculation, and presentation. In the setting module, the user can interactively customize model parameters, compliances, resistance, Emax of the ventricular contractility, total blood volume, and unstressed volume. The hemodynamics are calculated in three phases: filling (late diastole), ejection (systole), and flow (early diastole). In response to the user's settings, the simulator graphically presents the hemodynamics: the pressure-volume relations of the artery, vein, and ventricle, the venous return curves, and the stroke volume curves. The mean filling pressure is calculated at approximately 7 mmHg at the initial setting. The venous return curves, linear and concave, are dependent on the venous compliance. The hemodynamic equilibrium point is marked on the crossing point of venous return curve and the stroke volume curve. Users can interactively do discovery learning, and try and confirm their interests and get their questions answered about hemodynamic concepts by using the simulator.


Assuntos
Hemodinâmica , Veias , Animais , Humanos , Veias/fisiologia , Volume Sistólico , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia
17.
Nature ; 628(8008): 612-619, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38509366

RESUMO

There is increasing interest in how immune cells in the meninges-the membranes that surround the brain and spinal cord-contribute to homeostasis and disease in the central nervous system1,2. The outer layer of the meninges, the dura mater, has recently been described to contain both innate and adaptive immune cells, and functions as a site for B cell development3-6. Here we identify organized lymphoid structures that protect fenestrated vasculature in the dura mater. The most elaborate of these dural-associated lymphoid tissues (DALT) surrounded the rostral-rhinal confluence of the sinuses and included lymphatic vessels. We termed this structure, which interfaces with the skull bone marrow and a comparable venous plexus at the skull base, the rostral-rhinal venolymphatic hub. Immune aggregates were present in DALT during homeostasis and expanded with age or after challenge with systemic or nasal antigens. DALT contain germinal centre B cells and support the generation of somatically mutated, antibody-producing cells in response to a nasal pathogen challenge. Inhibition of lymphocyte entry into the rostral-rhinal hub at the time of nasal viral challenge abrogated the generation of germinal centre B cells and class-switched plasma cells, as did perturbation of B-T cell interactions. These data demonstrate a lymphoid structure around vasculature in the dura mater that can sample antigens and rapidly support humoral immune responses after local pathogen challenge.


Assuntos
Dura-Máter , Imunidade Humoral , Tecido Linfoide , Veias , Administração Intranasal , Antígenos/administração & dosagem , Antígenos/imunologia , Medula Óssea/imunologia , Sistema Nervoso Central/irrigação sanguínea , Sistema Nervoso Central/imunologia , Dura-Máter/irrigação sanguínea , Dura-Máter/imunologia , Centro Germinativo/citologia , Centro Germinativo/imunologia , Vasos Linfáticos/imunologia , Tecido Linfoide/irrigação sanguínea , Tecido Linfoide/imunologia , Plasmócitos/imunologia , Crânio/irrigação sanguínea , Linfócitos T/imunologia , Veias/fisiologia , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Animais , Camundongos , Idoso de 80 Anos ou mais
18.
Eur J Radiol ; 174: 111397, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452733

RESUMO

PURPOSE: To investigate quantitative changes in MRI signal intensity (SI) and lesion volume that indicate treatment response and correlate these changes with clinical outcomes after percutaneous sclerotherapy (PS) of extremity venous malformations (VMs). METHODS: VMs were segmented manually on pre- and post-treatment T2-weighted MRI using 3D Slicer to assess changes in lesion volume and SI. Clinical outcomes were scored on a 7-point Likert scale according to patient perception of symptom improvement; treatment response (success or failure) was determined accordingly. RESULTS: Eighty-one patients with VMs underwent 125 PS sessions. Treatment success occurred in 77 patients (95 %). Mean (±SD) changes were -7.9 ± 24 cm3 in lesion volume and -123 ± 162 in SI (both, P <.001). Mean reduction in lesion volume was greater in the success group (-9.4 ± 24 cm3) than in the failure group (21 ± 20 cm3) (P =.006). Overall, lesion volume correlated with treatment response (ρ = -0.3, P =.004). On subgroup analysis, volume change correlated with clinical outcomes in children (ρ = -0.3, P =.03), in sodium tetradecyl sulfate-treated lesions (ρ = -0.5, P =.02), and in foot lesions (ρ = -0.6, P =.04). SI change correlated with clinical outcomes in VMs treated in 1 PS session (ρ = -0.3, P =.01) and in bleomycin-treated lesions (ρ = -0.4, P =.04). CONCLUSIONS: Change in lesion volume is a reliable indicator of treatment response. Lesion volume and SI correlate with clinical outcomes in specific subgroups.


Assuntos
Escleroterapia , Malformações Vasculares , Criança , Humanos , Soluções Esclerosantes/uso terapêutico , Estudos Retrospectivos , Malformações Vasculares/diagnóstico por imagem , Malformações Vasculares/terapia , Veias , Resultado do Tratamento
19.
Surg Radiol Anat ; 46(4): 543-550, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429406

RESUMO

PURPOSE: Our aim was to study the anatomy of the left and right main adrenal veins (LAV and RAV) and to identify their anatomical variations in order to see the practical application of these findings to adrenal venous sampling (AVS). METHODS: Our work is based on dissection of 80 adrenal glands from fresh corpses in the forensic medicine department. We studied the number, the drainage, the direction and the level of termination of the main adrenal veins. RESULTS: The average length of the LAV was 21 mm. It ended in 100% of cases at the upper edge of the left renal vein with a mean connection angle of 70° and after an anastomosis with the lower phrenic vein in 36 cases(90%). The average length of the RAV was 9 mm. It ended in 100% of cases at the level of the retro hepatic inferior vena cava (IVC) mainly on its posterior face in 21 cases (53%) and on its right lateral border in 18 cases (45%). The mean angle of the RAV in relation to the vertical axis of the IVC was 40°, with extremes ranging from 15° to 90°. CONCLUSIONS: AVS seems to be easier on the left than on the right side because of the greater length of the adrenal vein (21 mm vs. 9 mm) and a greater angle of connection (70° with the left renal vein vs. 40° with the IVC), which explains the lower success rate of cannulation and the more frequent occurrence of blood sample contamination on the right side.


Assuntos
Glândulas Suprarrenais , Veias , Humanos , Veias/anatomia & histologia , Veia Cava Inferior , Veias Renais/anatomia & histologia , Estudos Retrospectivos
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