Purpose.: This study explores variation in the axial location of Bruch's membrane opening (BMO) to determine if this reference plane varies with age and race. Methods.: There were 168 spectral-domain optical coherence tomography (SDOCT) optic nerve head volumes that obtained from healthy subjects manually delineated within 24 slices develop point clouds for anterior scleral surfaces. A BMO-independent was generated based on peripapillary sclera measure BMO position. General estimating...

Purpose: To assess if the in vivo mechanical displacement of anterior laminar cribrosa surface (ALCS) as a response an acute elevation intraocular pressure (IOP) differs individuals European (ED) and African descent (AD). Methods: Spectral-domain optical coherence tomography (SDOCT) scans were obtained from 24 eyes 12 AD 18 9 ED at their normal baseline IOP after 60 seconds using ophthalmodynamometry. Change depth (displacement) LC to prelaminar tissue (PLT) computed association with change...

This study examined the association between peripapillary choroidal thickness (PCT) with age and race in a group of African descent (AD) European (ED) subjects normal eyes.Optic nerve head images from enhanced depth imaging spectral-domain optical coherence tomography 166 eyes 84 AD ED were manually delineated to identify principal surfaces Bruch's membrane (BM), opening (BMO), anterior sclera (AS). Peripapillary was measured BM AS at increasing distance away BMO. The mean PCT compared...

Purpose: This study examined the peripapillary choroidal thickness (PCT) in nonarteritic ischemic optic neuropathy (NAION) comparison to contralateral eyes and normal eyes. Methods: We used enhanced depth imaging spectral-domain optical coherence tomography image nerve head of 20 NAION, 10 eyes, 102 Following compensation, scans were manually delineated identify relevant surfaces including Bruch's membrane opening (BMO), membrane, anterior sclera. The PCT was defined as measurement between...

In general, two quadric surface intersect in a space quartic curve. However, the intersection frequently degenerates to collection of plane curves. Degenerate cases are frequent geometric/solid modeling because degeneracies often required by design. Their detection is important degenerate intersections can be computed more easily and allow simpler treatment problems. this paper, we investigate problem for natural quadrics. Algorithms presented detect compute conic linear intersections. These...

A method of computing the intersection a plane and natural quadric surface is presented. This problem basic in geometric areas such as solid modeling descriptive geometry. Our method, arising out recent work on lower degree intersections quadrics, computes directions axes intersection, then their lengths using Dandelin sphere. The also gives all parallel sections quadric, with no added computation.

Abstract To determine whether exercise‐induced ischemia impairs left ventricular diastolic filling in the postischemic period humans, 101 men (mean age 57±10 years) were studied before and 2 h after a symptom‐limited thallium‐201 tomographic treadmill with pulsed Doppler echocardiography of mitral valve inflow. In exercise, was significantly impaired group (reversible thallium defect; n = 24) as reflected by decrease peak early velocity (44.5±10.1 to 39.9±9.9 cm/s, p<0.01), atrial ratio...

Abstract This paper shows how to construct a rational Bezier model of swept surface that interpolates N frames (i.e., position/orientation pairs) fixed space curve c(s) and maintains the shape at all intermediate points sweep. Thus, models an exact sweep curve, consistent with given data. The primary novelty method is this modeling achieved without sacrificing representation for surface. Through simple extension, we also allow sweeping change its size through position, orientation, can...

Article On the planar intersection of natural quadrics Share on Authors: Ching-Kuang Shene Department Computer Science, The Johns Hopkins University, Baltimore, Maryland MarylandView Profile , John K. Johnstone Authors Info & Claims SMA '91: Proceedings first ACM symposium Solid modeling foundations and CAD/CAM applicationsMay 1991 Pages 233–242https://doi.org/10.1145/112515.112546Online:01 May 1991Publication History 3citation356DownloadsMetricsTotal Citations3Total Downloads356Last 12...

Generalized cylinders (GCs) are a popular representational tool in computer vision. In medical imaging, the curved axis GC is particularly applicable to number of elongated physical structures such as vasculature, bone and bronchi. many these instances, it necessary recover curved-axis GCs with arbitrary cross-sections. It also vital that structures, once recovered, can be analyzed visualized off-the-shelf algorithms software packages. Such tools usually designed operate on domain polynomial...

We present algorithms for computing the kernel of a closed freeform rational surface. The computation is reformulated as problem finding zero-sets polynomial equations; using these we characterize developable surface patches and planar that belong to boundary kernel. Using plane-point duality, this paper also explores duality relationship between convex hull its tangential

We study the problem of place recognition. Given a photo, we estimate its location by scene matching to large database internet photos known locations. Traditional strategies, which involve linear scan find scenes, fail scale. On other hand, contain massive amount noise and redundancy, is little help for By exploiting distribution photos, summarize set canonical views. The views eliminates redundancy in provides compact representation database. restricting views, observe good tradeoff...

We present a method for constructing tensor product Bezier surfaces from contour (cross-section) data. Minimal area triangulations are used to guide the surface construction, and final reflects optimality of triangulation. The resulting differs initial triangulation in two important ways: it is smooth (as opposed piecewise planar triangulation), form irregular triangular mesh). reconstruction efficient because we do not require an exact minimal surface. as strong hints, but no more than...

An operation that is frequently needed during the creation and manipulation of geometric models sorting points along an algebraic curve. Given a segment $\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{AB}$ curve, set on curve sorted from A to B by putting them into order they would be encountered in traveling continuously $\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\frown}$}}{AB}$. new method for plane or space presented. Key steps this are decomposition convex...

We develop an efficient algorithm for the construction of common tangents between a set Bezier curves. Common are important in visibility, lighting, robot motion, and convex hulls. tangency is reduced to intersection parametric curves dual space, rather than traditional implicit show how represent tangent space plane curve as rational compare this representation hodograph curve. The detection that map infinity resolved by use two cooperating clipped avoid redundancy. establish equivalence...

Biological videos are very different from conventional videos. Automatic spatiotemporal mining of moving cells in vivo microscopy is extremely difficult because the severe noises, camera/subject movements, deformations, and strong dependencies on operators. In this paper, we present an automatic system rolling adherent leukocytes for intravital The magnitude leukocyte adhesion decrease velocity common interests inflammation response studies. Currently, there no existing which perfect such...

Automobile detection based on feature tracking has proven effective in handling vehicle occlusions. However, current systems adopt a single camera to compute the 3D coordinates of points, which leads an under-conditioned problem. As result, only few stable features can be reconstructed successfully. In this paper, we extend system by adding second camera, and integrate structure from motion (SfM) techniques reconstruct large volume points without sacrificing accuracy.