A kinect-aided method to estimate the fundus camera extrinsic parameters for three-dimensional reconstruction of retinal blood vessels

2016 ◽  
Author(s):  
E. Hernandez-Sanchez ◽  
M. Elena Martinez-Perez ◽  
A. Gastelum-Strozzi
Keyword(s):  
Blood Vessels ◽  
Three Dimensional ◽  
Three Dimensional Reconstruction ◽  
Fundus Camera ◽  
Retinal Blood Vessels ◽  
Extrinsic Parameters ◽  
Dimensional Reconstruction

scholarly journals Features of Blood Supply to the Bones of the Lower Leg in the Ankle Joint Region

2021 ◽  
Vol 6 (6) ◽  
pp. 74-79
Author(s):  
I. Yu. Oliinyk ◽  
◽  
O. V. Tsyhykalo ◽  
O. A. Koval
Keyword(s):  
Bone Marrow ◽  
Blood Vessels ◽  
Three Dimensional ◽  
Prenatal Development ◽  
Lower Leg ◽  
Three Dimensional Reconstruction ◽  
Distal Metaphysis ◽  
Nutrient Foramina ◽  
Dimensional Reconstruction ◽  
Upper Third

The purpose of the study was to investigate the topography of permeable (nutrition) arteries in the lower third of leg during human ontogenesis. Materials and methods. The research was conducted on 30 specimens of human prefetuses and fetuses aged 3-9 months of prenatal development; 28 bone specimens of adult tibia and fibula and 27 series of computerized tomography scans of lower extremities of adults aged 21-72 were used. We have used a complex of methods for morphological research: anthropometry, morphometry, macromicroscopy, injections of blood vessels of X-ray contrasting mixtures, three-dimensional reconstruction and statistical analysis. Results and discussion. Cartilage osteogenesis occurs in the prefetal period of prenatal human development, in which blood vessels play a crucial morphofunctional role. During endochondral ossification of the tibia, the vessels of the bone cuff grow into the diaphysis of the cartilaginous model of the bone and osteogenic cells go beyond their limits. In the third trimester of prenatal development, blood vessels grow into the epiphyseal part of the cartilaginous model and an epiphyseal centre of ossification forms. Between the epiphysis and diaphysis centers of ossification, a metaphysical growth plate forms that develops intraosseous anastomosis between the diaphyseal and metaphysical blood vessels. In the metaphysis region, there are extra-skeletal anastomoses. Often, the insertion of nutrition arteries into the bone of the tibia is usually the middle third of bones (55%) and distal metaphysis (37%). In 10%, there were nutrition foramina in the upper third of the tibia. Three-dimensional reconstruction also clearly shows a more extensive and developed network of vessels in the bone marrow canal in metaphysical regions. In the middle third of the tibia and fibula, 1-3 nutrient foramina can be traced on most specimens. On the fibular, in addition to the posterior-medial localization of the nutrient arteries, there were variants with a "high" (above the metaphysis) placement of the entrance of the vessel into the bone substance. Conclusion. The most common places where arteries enter the bones of the lower leg are the middle third of the bones (55%) and the distal metaphysis (37%). In 10%, there were nutrient foramina in the upper third of the tibia. The three-dimensional reconstruction also clearly shows a more extensive and developed network of vessels in the bone marrow canal in metaphysical regions. During the postnatal period, we most often encountered the localization of nutritional arteries on the anterior-lateral surface of the tibia (23%), or their combination – the presence of both nutrient arteries on the posterior and medial bone surfaces (18.3%)

scholarly journals Three-Dimensional Reconstruction of Two-Dimensional Cardiovascular Angiography Image Sequences by Local Threshold Segmentation Algorithm

2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Shenming Yu
Keyword(s):  
Blood Vessel ◽  
Blood Vessels ◽  
Three Dimensional ◽  
Segmentation Algorithm ◽  
Two Dimensional ◽  
Three Dimensional Reconstruction ◽  
Gaussian Smoothing ◽  
Threshold Segmentation ◽  
Local Threshold ◽  
Dimensional Reconstruction

The study focused on the extraction of cardiovascular two-dimensional angiography sequences and the three-dimensional reconstruction based on the local threshold segmentation algorithm. Specifically, the two-dimensional cardiovascular angiography sequence was extracted first, and Gaussian smoothing was adopted for image preprocessing. Then, optimize maximum between-class variance (OSTU) was compared with the traditional two-dimensional OSTU and fast two-dimensional OSTU and applied in the segmentation of cardiovascular angiography images. It was found that the cardiovascular structure itself was continuous, the contrast agent diffused relatively evenly in the blood vessel, and the gray level of the blood vessel was also continuous. The degree of smoothness was consistent in all directions by Gaussian smoothing, avoiding the direction deviation of the smoothened image. The operation time (0.59 s) of the optimize OSTU was significantly shorter than that of traditional OSTU (35.68 s) and fast two-dimensional OSTU (6.34 s) ( P < 0.05 ). The local threshold segmentation algorithm can realize the continuous edge extraction of blood vessels and accurately reflect the stenosis of blood vessels. The results of blood vessel diameter measurement showed that the diameter from the end of blood vessel to the intersection varied linearly from 5.5 mm to 9.0 mm. In short, the optimize OSTU demonstrated good segmentation effects and fast calculation time; it successfully extracted continuous two-dimensional cardiovascular angiography images and can be used in three-dimensional reconstruction of cardiovascular images.

MR imaging of blood vessels using three-dimensional reconstruction: methodology.

Radiology ◽  
1985 ◽  
Vol 157 (3) ◽  
pp. 727-733 ◽  
Author(s):  
J D Hale ◽  
P E Valk ◽  
J C Watts ◽  
L Kaufman ◽  
L E Crooks ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Blood Vessels ◽  
Three Dimensional ◽  
Three Dimensional Reconstruction ◽  
Dimensional Reconstruction
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