Marker-less assessment of the geometric error of fused cone-beam computed tomography images of the foot constructed using stitching software.

Background: Image noise, object repositioning, initial manual image alignment, and stitching of different volumes, i.e. anatomical regions may all affect the stitching error of fused cone-beam computed tomography (CBCT) images.

Enhancement of red blood cell transfusion compatibility using CRISPR-mediated erythroblast gene editing.

Regular blood transfusion is the cornerstone of care for patients with red blood cell (RBC) disorders such as thalassaemia or sickle-cell disease. With repeated transfusion, alloimmunisation often occurs due to incompatibility at the level of minor blood group antigens. We use CRISPR-mediated genome editing of an immortalised human erythroblast cell line (BEL-A) to generate multiple enucleation competent cell lines deficient in individual blood groups.

Estimating Scaphoid Lengths Using Anatomical Measurements in the Wrist.

Purpose: In reconstructive surgery of scaphoid nonunions with humpback deformity, some surgeons recommend restoration of the normal scaphoid length whereas others overexpand the normal length to ensure carpal realignment and prevent late collapse. To be able to define overexpansion and investigate which levels of overexpansion yield optimal clinical results, a precise method for estimating the original scaphoid length is required. The purpose of this anatomic study was to investigate the precision of estimating normal scaphoid lengths based on intact adjacent bone dimensions, compared with using the contralateral scaphoid length.

Validation of the contralateral side as reference for selecting radial head implant sizes.

Purpose: In arthroplasty of comminuted radial head fractures, the contralateral radial head diameter can be used as reference for implant selection. However, potential bilateral asymmetry may result in a mismatch of the implant with the native bone. Therefore, our purpose was to evaluate anatomical right-to-left differences of radial head diameters.

The Mechanical Functionality of the EXO-L Ankle Brace: Assessment With a 3-Dimensional Computed Tomography Stress Test.

Background: A new type of ankle brace (EXO-L) has recently been introduced. It is designed to limit the motion of most sprains without limiting other motions and to overcome problems such as skin irritation associated with taping or poor fit in the sports shoe.

Purpose: To evaluate the claimed functionality of the new ankle brace in limiting only the motion of combined inversion and plantar flexion.

Three-Dimensional Assessment of Bilateral Symmetry of the Scaphoid: An Anatomic Study.

Preoperative 3D CT imaging techniques provide displacement analysis of the distal scaphoid fragment in 3D space, using the matched opposite scaphoid as reference. Its accuracy depends on the presence of anatomical bilateral symmetry, which has not been investigated yet using similar techniques. Our purpose was to investigate symmetry by comparing the relative positions of distal and proximal poles between sides.

Quantifying scaphoid malalignment based upon height-to-length ratios obtained by 3-dimensional computed tomography.

Purpose: To determine if 3-dimensional height-to-length (H/L) measurements including coronal plane assessment will improve malalignment detection of scaphoid fractures and to determine if more waist than proximal pole nonunions are malaligned.

Methods: Computed tomography scans of uninjured wrists (n = 74) were used to obtain 3-dimensional models of healthy scaphoids. These models were used to determine 95% normal ranges of the H/L ratio in standard sagittal and coronal planes in an automated fashion.

Accuracy of distal radius positioning using an anatomical plate.

Over the past decade, several anatomical plates have been introduced to improve the result of open reduction and internal fixation of the distal radius. Using 3-dimensional imaging techniques, the authors studied the accuracy and reproducibility of distal radius positioning using anatomical plates.Distal radius fractures and the correction of these fractures were simulated with plastic bone models of radii.

Positioning evaluation of corrective osteotomy for the malunited radius: 3-D CT versus 2-D radiographs.

The authors retrospectively investigated the postoperative position of the distal radius after a corrective osteotomy using 2-dimensional (2-D) and 3-dimensional (3-D) imaging techniques to determine whether malposition correlates with clinical outcome. Twenty-five patients who underwent a corrective osteotomy were available for follow-up. The residual positioning errors of the distal end were determined retrospectively using standard 2-D radiographs and 3-D computed tomography evaluations based on a scan of both forearms, with the contralateral healthy radius serving as reference.

3D Imaging of vascular networks for biophysical modeling of perfusion distribution within the heart.

One of the main determinants of perfusion distribution within an organ is the structure of its vascular network. Past studies were based on angiography or corrosion casting and lacked quantitative three dimensional, 3D, representation. Based on branching rules and other properties derived from such imaging, 3D vascular tree models were generated which were rather useful for generating and testing hypotheses on perfusion distribution in organs.

Rapid automatic assessment of microvascular density in sidestream dark field images.

The purpose of this study was to develop a rapid and fully automatic method for the assessment of microvascular density and perfusion in sidestream dark field (SDF) images. We modified algorithms previously developed by our group for microvascular density assessment and introduced a new method for microvascular perfusion assessment. To validate the new algorithm for microvascular density assessment, we reanalyzed a selection of SDF video clips (n = 325) from a study in intensive care patients and compared the results to (semi-)manually found microvascular densities.

Strain hardening of red blood cells by accumulated cyclic supraphysiological stress.

The effect of elevated shear stress upon cellular trauma has been studied for many years, but the effect of long-term cyclic stress trauma on hemorheology has never been explored systematically. This study investigated sublytic trauma of red blood cells (RBCs) caused by repeated exposure to shear stress. A suspension of bovine blood was throttled through a capillary tube (inner diameter 1 mm and length 70 mm) connected to a recirculating flow loop.

Syllectometry: the effect of aggregometer geometry in the assessment of red blood cell shape recovery and aggregation.

Syllectometry is a measuring method that is commonly used to assess red blood cell (RBC) aggregability. In syllectometry, light is incident on a layer of whole blood initially exposed to shear flow. The backscattered light is measured after abruptly stopping the driving mechanism.