3D ultrasound volume quantification for pediatric urinary tract dilation: a semi-automated segmentation software inter-rater analysis.

Objective: We determined the reliability of a three-dimensional (3D) ultrasound (US) segmentation software for evaluating volumetric hydronephrosis index (HI) and renal parenchymal and pelvicalyceal volume in children with urinary tract dilation (UTD).

Material And Methods: From 1/2019 to 9/2023, children clinically scheduled for a renal imaging exam to assess UTD at a single center were prospectively enrolled. They underwent a dedicated two-dimensional (2D) and 3D US renal exam.

The Emu Bay Shale: A unique early Cambrian Lagerstätte from a tectonically active basin.

The Emu Bay Shale (EBS) of South Australia is anomalous among Cambrian Lagerstätten because it captures anatomical information that is rare in Burgess Shale-type fossils, and because of its inferred nearshore setting, the nature of which has remained controversial. Intensive study, combining outcrop and borehole data with a compilation of >25,000 fossil specimens, reveals that the EBS biota inhabited a fan delta complex within a tectonically active basin. Preservation of soft-bodied organisms in this setting is unexpected and further underscores differences between the EBS and other Cambrian Lagerstätten.

Three-Dimensional Multi-Frequency Shear Wave Absolute Vibro-Elastography (3D S-WAVE) With a Matrix Array Transducer: Implementation and Preliminary In Vivo Study of the Liver.

Magnetic resonance elastography (MRE) is commonly regarded as the imaging-based gold-standard for liver fibrosis staging, comparable to biopsy. While ultrasound-based elastography methods for liver fibrosis staging have been developed, they are confined to a 1D or a 2D region of interest and to a limited depth. 3D Shear Wave Absolute Vibro-Elastography (S-WAVE) is a steady-state, external excitation, volumetric elastography technique that is similar to MRE, but has the additional advantage of multi-frequency excitation.

Comparison of Variations Between Spectral Doppler and Gaussian Surface Integration Methods for Umbilical Vein Blood Volume Flow.

Objectives: We are studying a new method for estimating blood volume flow that uses 3-dimensional ultrasound to measure the total integrated flux through an ultrasound-generated Gaussian surface that intersects the umbilical cord. This method makes none of the assumptions typically required with standard 1-dimensional spectral Doppler volume flow estimates. We compared the variations in volume flow estimates between techniques in the umbilical vein.

Pilot study of the potential of 3D ultrasound to measure tonsillar volume and hypertrophy.

Objective: Obstructive sleep apnea (OSA), results in approximately 4-5 million outpatient visits per year in the United States. In pediatric patients, OSA is primarily caused by adenotonsillar hypertrophy, and therefore, adenotonsillectomy remains an effective surgical treatment. We investigate whether 3D ultrasound (3DUS) imaging can accurately and objectively assess tonsillar hypertrophy for the potential identification and stratification of candidates for adenotonsillectomy.

Partial Volume Effect and Correction for 3-D Color Flow Acquisition of Volumetric Blood Flow.

Blood volume flow (VF) estimation is becoming an integral part of quantitative medical imaging. Three-dimensional color flow can be used to measure volumetric flow, but partial volume correction (PVC) is essential due to finite beamwidths and lumen diameters. Color flow power was previously assumed to be directly proportional to the perfused fractional color flow beam area (voxel).

In Vivo Validation of Volume Flow Measurements of Pulsatile Flow Using a Clinical Ultrasound System and Matrix Array Transducer.

The goal of this study was to evaluate the accuracy of a non-invasive C-plane Doppler estimation of pulsatile blood flow in the lower abdominal vessels of a porcine model. Doppler ultrasound measurements from a matrix array transducer system were compared with invasive volume flow measurements made on the same vessels with a surgically implanted ultrasonic transit-time flow probe. For volume flow rates ranging from 60 to 750 mL/min, agreement was very good, with a Pearson correlation coefficient of 0.

Renal Segmentation From 3D Ultrasound via Fuzzy Appearance Models and Patient-Specific Alpha Shapes.

Ultrasound (US) imaging is the primary imaging modality for pediatric hydronephrosis, which manifests as the dilation of the renal collecting system (CS). In this paper, we present a new framework for the segmentation of renal structures, kidney and CS, from 3DUS scans. First, the kidney is segmented using an active shape model-based approach, tailored to deal with the challenges raised by US images.

Quantification of kidneys from 3D ultrasound in pediatric hydronephrosis.

This paper introduces a complete framework for the quantification of renal structures (parenchyma, and collecting system) in 3D ultrasound (US) images. First, the segmentation of the kidney is performed using Gabor-based appearance models (GAM), a variant of the popular active shape models, properly tailored to the imaging physics of US image data. The framework also includes a new graph-cut based method for the segmentation of the collecting system, including brightness and contrast normalization, and positional prior information.

A hierarchical model for automated breast lesion detection from ultrasound 3D data.

Ultrasound imaging plays an important role in breast cancer screening for which early and accurate lesion detection is crucial for clinical practice. Many researches were performed on supporting the breast lesion detection based on ultrasound data. In the paper, a novel hierarchical model is proposed to automatically detect breast lesion from ultrasound 3D data.

A new vetulicolian from Australia and its bearing on the chordate affinities of an enigmatic Cambrian group.

Background: Vetulicolians are one of the most problematic and controversial Cambrian fossil groups, having been considered as arthropods, chordates, kinorhynchs, or their own phylum. Mounting evidence suggests that vetulicolians are deuterostomes, but affinities to crown-group phyla are unresolved.

Results: A new vetulicolian from the Emu Bay Shale Konservat-Lagerstätte, South Australia, Nesonektris aldridgei gen.

Acute vision in the giant Cambrian predator Anomalocaris and the origin of compound eyes.

Until recently, intricate details of the optical design of non-biomineralized arthropod eyes remained elusive in Cambrian Burgess-Shale-type deposits, despite exceptional preservation of soft-part anatomy in such Konservat-Lagerstätten. The structure and development of ommatidia in arthropod compound eyes support a single origin some time before the latest common ancestor of crown-group arthropods, but the appearance of compound eyes in the arthropod stem group has been poorly constrained in the absence of adequate fossils. Here we report 2-3-cm paired eyes from the early Cambrian (approximately 515 million years old) Emu Bay Shale of South Australia, assigned to the Cambrian apex predator Anomalocaris.

Modern optics in exceptionally preserved eyes of Early Cambrian arthropods from Australia.

Despite the status of the eye as an "organ of extreme perfection", theory suggests that complex eyes can evolve very rapidly. The fossil record has, until now, been inadequate in providing insight into the early evolution of eyes during the initial radiation of many animal groups known as the Cambrian explosion. This is surprising because Cambrian Burgess-Shale-type deposits are replete with exquisitely preserved animals, especially arthropods, that possess eyes.

On the stability of the effective apodization of the nonlinearly generated second harmonic with respect to range.

The concept of an effective apodization was introduced to describe the field pattern for the nonlinearly generated second harmonic (2f) within the focal zone using a linear propagation model. Our objective in this study was to investigate the validity of the concept of an effective apodization at 2f as an approach to approximating the field of the second harmonic over a wide range of depths. Two experimental setups were employed: a vascular imaging array with a water path and an adult cardiac imaging array with an attenuating liver path.

Spatial coherence of backscatter for the nonlinearly produced second harmonic for specific transmit apodizations.

To be successful, correlation-based, phase-aberration correction requires a high correlation among backscattered signals. For harmonic imaging, the spatial coherence of backscatter for the second harmonic component is different than the spatial coherence of backscatter for the fundamental component. The purpose of this work was to determine the effect of changing the transmit apodization on the spatial coherence of backscatter for the nonlinearly generated second harmonic.

Spatial coherence of the nonlinearly generated second harmonic portion of backscatter for a clinical imaging system.

Correlation-based approaches to phase aberration correction rely on the spatial coherence of backscattered signals. The spatial coherence of backscatter from speckle-producing targets is predicted by the auto correlation of the transmit apodization (Van Cittert-Zernike theorem). Work by others indicates that the second harmonic beam has a wider mainlobe with lower sidelobes than a beam transmitted at 2f.