Microfluidic technologies for vasculature biomimicry

The role of endovascular interventions has progressed rapidly over the past several decades. While animal models have long-served as the mainstay for the advancement of this field, the use of in vitro models has become increasingly widely adopted with recent advances in engineering technologies. Here, we review the strategies, mainly including bioprinting and microfabrication, which allow for fabrication of biomimetic vascular models that will potentially serve to supplement the conventional animal models for convenient investigations of endovascular interventions. Besides normal blood vessels, those in diseased states, such as thrombosis, may also be modeled by integrating cues that simulate the microenvironment of vascular disorders. These novel engineering strategies for the development of biomimetic in vitro vascular structures will possibly enable unconventional means of studying complex endovascular intervention problems that are otherwise hard to address using existing models.

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Variations and Abnormalities of Major Thoracic Vascular Structures

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/157340561002140715102114 ◽

2014 ◽

Vol 10 (2) ◽

pp. 113-118

Author(s):

Abdurrahman Oran ◽

Cemil Goya ◽

Hasan Nazaroglu

Keyword(s):

Vascular Structures

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Structure-function relationships in the feto-placental circulation from in silico interpretation of micro-CT vascular structures

Placenta ◽

10.1016/j.placenta.2019.06.267 ◽

2019 ◽

Vol 83 ◽

pp. e84

Author(s):

Monika Byrne ◽

Rosalind Aughwane ◽

Joanna James ◽

Ciaran Hutchinson ◽

Owen Arthurs ◽

...

Keyword(s):

Structure Function ◽

In Silico ◽

Micro Ct ◽

Vascular Structures

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Rapid synchronized fabrication of vascularized thermosets and composites

Nature Communications ◽

10.1038/s41467-021-23054-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Mayank Garg ◽

Jia En Aw ◽

Xiang Zhang ◽

Polette J. Centellas ◽

Leon M. Dean ◽

...

Keyword(s):

Large Scale ◽

Capillary Flow ◽

External Heat ◽

Frontal Polymerization ◽

Self Healing ◽

Vascular Networks ◽

Ambient Conditions ◽

External Energy ◽

Imaging Phantoms ◽

Vascular Structures

AbstractBioinspired vascular networks transport heat and mass in hydrogels, microfluidic devices, self-healing and self-cooling structures, filters, and flow batteries. Lengthy, multistep fabrication processes involving solvents, external heat, and vacuum hinder large-scale application of vascular networks in structural materials. Here, we report the rapid (seconds to minutes), scalable, and synchronized fabrication of vascular thermosets and fiber-reinforced composites under ambient conditions. The exothermic frontal polymerization (FP) of a liquid or gelled resin facilitates coordinated depolymerization of an embedded sacrificial template to create host structures with high-fidelity interconnected microchannels. The chemical energy released during matrix polymerization eliminates the need for a sustained external heat source and greatly reduces external energy consumption for processing. Programming the rate of depolymerization of the sacrificial thermoplastic to match the kinetics of FP has the potential to significantly expedite the fabrication of vascular structures with extended lifetimes, microreactors, and imaging phantoms for understanding capillary flow in biological systems.

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Neurosurgical anatomy of the floor of the third ventricle and related vascular structures

Surgical and Radiologic Anatomy ◽

10.1007/s00276-021-02785-8 ◽

2021 ◽

Author(s):

João Fernandes-Silva ◽

Susana M. Silva ◽

Hélio Alves ◽

José P. Andrade ◽

Mavilde Arantes

Keyword(s):

Third Ventricle ◽

The Third ◽

Vascular Structures

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THE DEVELOPMENT OF HEPATIC VASCULAR STRUCTURES*

Annals of the New York Academy of Sciences ◽

10.1111/j.1749-6632.1963.tb36951.x ◽

2006 ◽

Vol 111 (1) ◽

pp. 105-109 ◽

Cited By ~ 16

Author(s):

Alexander Barry

Keyword(s):

Vascular Structures

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Can the Human Tail Cause Arteriovenous Hemangioma?

Pediatric Neurosurgery ◽

10.1159/000511877 ◽

2020 ◽

pp. 1-5

Author(s):

Pinar Aydin Ozturk ◽

Seyhmus Kaya

Keyword(s):

Skin Color ◽

Squamous Epithelium ◽

Normal Skin ◽

Distal Portion ◽

Vascular Lesion ◽

Pathological Findings ◽

Lumbosacral Region ◽

Fibrous Stroma ◽

Human Tail ◽

Vascular Structures

Introduction: “Human tail” is a congenital, benign anomaly in which a protrusion in the lumbosacrococcygeal caudal region is covered with skin. Arteriovenous hemangioma is a benign vascular lesion that may be congenital or acquired. We present a case in which a human tail was present with pathological findings of arteriovenous hemangioma. Case Report: A 6-month-old girl was born with a curved tail-shaped protrusion along her waistline. The distal portion was purple and had a solid consistency; the proximal portion was of normal skin color and had a soft consistency. No other abnormality was observed in the spinal area. Microscopic examination revealed congested, proliferated vascular structures in the fibrous stroma distally located under the multilayered squamous epithelium. In the proximal area, mature lipomatous tissue was observed. The lesion was diagnosed as arteriovenous hemangioma. Conclusion: Our patient presented with the classic “human tail” appearance at an early age and in the lumbosacral region. Because of the pathological findings, surgery for the congenital anomaly had to be performed with extra caution.

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Surgical Complications Requiring Intervention in Open versus Minimally Invasive Radical Prostatectomy

Urologia Internationalis ◽

10.1159/000515618 ◽

2021 ◽

pp. 1-5

Author(s):

Lorine Haeuser ◽

Stephen W. Reese ◽

Marco Paciotti ◽

Joachim Noldus ◽

Ethan Y. Brovman ◽

...

Keyword(s):

Radical Prostatectomy ◽

Minimally Invasive ◽

Surgical Approach ◽

Large Bowel ◽

Bowel Injury ◽

Improvement Program ◽

Significant Difference ◽

American College Of Surgeons ◽

Vascular Structures ◽

Open Versus

Introduction: Injuries to surrounding structures during radical prostatectomy (RP) are rare but serious complications. However, it remains unknown if injuries to intestines, rectum, or vascular structures occur at different rates depending on the surgical approach. Methods: We compared the frequency of these outcomes in open RP (ORP) and minimally invasive RP (MIS-RP) using the national American College of Surgeons National Surgical Quality Improvement Program database (2012–2017). Along with important metrics of clinical and surgical outcomes, patients were identified as undergoing surgical repair of small or large bowel, vascular structures, or hernias based on Current Procedural Terminology codes. Results: In our propensity matched analysis, a total of 13,044 patients were captured. Bowel injury occurred more frequently in ORP than in MIS-RP (0.89 vs. 0.26%, p < 0.01). By intestinal segment, rectal and large bowel injuries were more common in ORP than MIS-RP (0.41 vs. 0.11% and 0.31 vs. 0.05%, both p < 0.01). However, there was no statistically significant difference between the groups for small bowel injury (0.17 vs. 0.11%, p = 0.39). Vascular injury was more common in MIS-RP (0.18 vs. 0.08%, p = 0.08). Hernias requiring repair were only identified in the MIS-RP group (0.12%). Conclusion: When considering surgical approach, rectal and large bowel injuries were more common in ORP, while vascular injuries and hernia repair were more common in MIS-RP. Our findings can be used in counseling patients and identifying risk factors and strategies to reduce these complications.

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The effect of sirolimus on angiomyolipoma is determined by decrease of fat-poor compartments and includes striking reduction of vascular structures

Scientific Reports ◽

10.1038/s41598-021-87930-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Elieser Hitoshi Watanabe ◽

Fernando Morbeck Almeida Coelho ◽

Hilton Leão Filho ◽

Bruno Eduardo Pedroso Balbo ◽

Precil Diego Miranda de Menezes Neves ◽

...

Keyword(s):

Tuberous Sclerosis ◽

Blood Vessels ◽

Tuberous Sclerosis Complex ◽

Hounsfield Unit ◽

Mtor Inhibitors ◽

Volume Reduction ◽

Tumor Reduction ◽

Vascular Structures ◽

Remarkable Reduction

AbstractRenal angiomyolipomas hemorrhage is associated with their size and vascular constitution. The effects of sirolimus on different components of angiomyolipomas was analyzed in patients with tuberous sclerosis complex, sporadic lymphangioleiomyomatosis and multiple sporadic angiomyolipomas. Thirty angiomyolipomas from 14 patients treated with sirolimus were retrospectively evaluated. A Hounsfield-unit threshold was used to classify angiomyolipomas in fat-rich, fat-poor and intermediate-fat tumors, and to categorize tumor compartments in fat rich, fat poor, intermediate fat and highly vascularized. Diameter variations were measured to assess the effects on aneurysmatic/ectatic vascular formations. Volume reduction following treatment with sirolimus was higher in fat-poor than fat-rich angiomyolipomas. Tumor reduction was mainly determined by decrease of the fat-poor and highly-vascularized compartments while the volume of the fat-rich compartment increased. Broad liposubstitution was observed in some tumors. A median reduction of 100% (75 to 100) in the diameter of aneurysmatic/ectatic vascular structures was observed. Our study showed that sirolimus reduces the size of angiomyolipomas by decreasing primarily their highly-vascularized and fat-poor compartments. This effect is associated with a remarkable reduction of tumoral aneurysms/ectatic vessels, revealing the likely mechanism responsible for the risk-decreasing effect of mTOR inhibitors on angiomyolipoma bleeding. These findings support the role of mTOR in the development of angiomyolipoma blood vessels.

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