Despite its demonstrated potential in the diagnosis and/or staging of disease, especially in oncology, tortuosity has not received a formal and unambiguous clinical definition yet. Using idealized three-dimensional vessel models (wavy helices) with known characteristics, we first demonstrate that, among various possible tortuosity indices, the standard deviation of the curvature Ksd best satisf...

Advances in noninvasive imaging techniques such as magnetic resonance perfusion imaging have been found useful in grading cerebral neoplasms and have potential for significant clinical benefit. The purpose of this study was to determine the correlation between tumor vessel tortuosity as measured from vessels extracted from magnetic resonance angiograms (MRA) and perfusion parameters of cerebral...

Background Turner syndrome is associated with bicuspid aortic valve (BAV), coarctation of the aorta, aortic dilation, and aortic dissection. Vertebral artery tortuosity, as demonstrated by magnetic resonance angiography (MRA), is increased in other disorders associated with thoracic aortic dilation and dissection, including Marfan syndrome and Loeys-Dietz syndrome, and increased tortuosity is a...

Background In pilot studies, increased vascular tortuosity is associated with adverse outcomes in children and young adults withheritable thoracic aortic disease, specifically Marfan syndrome (MFS) and Loeys Dietz syndrome (LDS). It is known that vertebral artery tortuosity is highly prevalent in older adults who do not have heritable thoracic aortic disease. We hypothesized that tortuosity inc...

BACKGROUND Coronary tortuosity (CorT) is a common angiographic finding and may be associated with myocardial ischaemia, even without coronary artery disease. Platelets play a crucial role in inflammatory and thrombotic processes and the physiopathology of cardiovascular disease. Larger platelets are more active enzymatically and have higher thrombotic ability compared to smaller platelets. Plat...

PURPOSE To determine whether the degree of venous tortuosity is significantly correlated with the aqueous vascular endothelial growth factor (VEGF) concentration in eyes with a central retinal vein occlusion (CRVO). METHODS We reviewed the medical records of 32 eyes of 32 patients who had macular edema due to a CRVO. All of the patients were examined at the Nagoya University Hospital and were...

PURPOSE Endothelial dysfunction and vascular disease are common in obstructive sleep apnea (OSA). We sought to examine the retinal vascular manifestations of OSA. METHODS Nine consecutive patients with OSA underwent ophthalmic examination regardless of any ocular complaints. Seven patients without OSA matched for demographics were used as controls. Fundus photographs from both eyes were used ...

A 3D microstructure of the non-woven gas diffusion layers (GDLs) of polymer electrolyte fuel cells (PEFCs) is reconstructed using a stochastic method. For a commercial GDL, due to the planar orientation of the fibers in the GDL, 2D SEM image of the GDL surface is used to estimate the orientation of the carbon fibers in the domain. Two more microstructures with different fiber orientations are g...

Introduction: Arterial tortuosity syndrome (ATS), an autosomal recessive rare connective tissue disorder characterized by tortuosity, elongation and stenosis in the large and medium sized arteries. It manifestations include vascular and nonvascular connective tissue related symptoms. In this literature we describe the first cases of ATS from Iran. Case report: A six-months-old female wa...