DOI: 10.5061/dryad.9zw3r22sx
title: Improving real-time ultrasound spine imaging with a large-aperture array

description: Ultrasound offers a safe, low-cost alternative to computed tomography (CT)
 and magnetic resonance imaging (MRI) for spinal diagnostics and
 intervention by enabling real-time imaging. However, the complex structure
 of the spine and acoustic shadowing from bones present challenges for
 ultrasonography. This study addresses these limitations using an 8.8-cm
 384-element large-aperture array and full aperture-based imaging
 protocols. Volumetric scanning across multiple vertebrae was accomplished
 in 5 seconds using ultrafast, diverging wave acquisition. In 7 healthy
 volunteers, the large-aperture array and diverging wave transmission
 improved resolution, contrast, and visualization of the spinal canal,
 venous plexuses, and facet joints compared with conventional probes. A
 comparison between the co-registered CT and ultrasound scan confirmed the
 imaging accuracy. A simulated lumbar puncture demonstrated needle tip
 visualization throughout the trajectory into the spinal canal. The results
 suggest that large-aperture arrays, coupled with plane or diverging
 protocols, are a valuable tool for spine imaging and image-guided
 intervention.
description: # Improving real-time ultrasound spine imaging with a large-aperture array
 Dataset DOI: [10.5061/dryad.9zw3r22sx](10.5061/dryad.9zw3r22sx) ##
 Description of the data and file structure The attached dataset includes
 raw data, processed data, and MATLAB scripts that are used for data
 processing for the paper entitled "Improving real-time ultrasound
 spine imaging with a large-aperture array". Overview of the raw data
 collection: Phantom data were collected with a standard ultrasound
 tissue-mimicking phantom (CIRS Model 040GSE) and a house-made
 tissue-mimicking spine phantom as described in the paper. Human spine
 images were collected from seven healthy human volunteers. All the human
 ultrasound imaging was performed following the protocol approved by the
 Institutional Review Board. Informed written consent was obtained from all
 7 volunteers involved in human spine imaging. Please see the details below
 for each zip file. ### Files and variables #### File: stats.zip
 **Description:** Original data and statistical analysis in Prism Graphpad.
 The ANOVA tests correspond to results presented in Fig. 4D. The
 Bland-Altman tests correspond to results presented in Fig. 5C and Fig. 6C.
 #### File: CIRSphantom.zip **Description:** Standard ultrasound phantom
 data and the MATLAB scripts used for data processing. Data description: *
 Humimicaberration: * Beamformed ultrasound data acquired with the CIRS
 phantom and the house-made humimic aberrator are named as
 "BFdata_acqTX_cdB.mat".
 For example, "BFdata_acq001_45TX_c1540_75dB_ver18.mat" refers to
 acquisition#001, which uses 45 transmission, and a sound speed of 1540m/s
 and a dynamic range of 75 dB for reconstruction. * The transmission type
 is denoted in the file name of workspace.mat file, where all ultrasound
 parameters associated with transmission sequence and reconstruction
 methods are saved. * workspace_PW_1.mat: parameter file for Acquisition
 #001 using plane wave (PW) transmission. * workspace_DW_2.mat: parameter
 file for Acquisition #002 using diverging wave (DW) transmission. *
 workspace_CW80_3.mat: parameter file for Acquisition #003 using converging
 wave (CW, i.e., focused beam) transmission with a focal depth of 80mm. *
 workspace_CW120_4.mat: parameter file for Acquisition #004 using
 converging wave (CW, i.e., focused beam) transmission with a focal depth
 of 120mm. * workspace_CW160_5.mat: parameter file for Acquisition #005
 using converging wave (CW, i.e., focused beam) transmission with a focal
 depth of 160mm. * noaberration: * Beamformed ultrasound data acquired with
 the CIRS phantom. The file name follows the same fashion as those in the
 "humimicaberration" folder. More details of the data collection
 can be found in the text file in each subfolder. MATLAB scripts
 description: * analyze_results_aber.m: script that was used to measure
 lateral resolution as a function of depth on the CIRS phantom with
 aberration. * analyze_results_noaber.m: script that was used to measure
 lateral resolution as a function of depth on the CIRS phantom without
 aberration. * gcnr_calc.m: MATLAB function that was used to calculate
 generalized contrast-to-noise ratio (gCNR) as part of image quality
 analysis. * .fig files: example figures produced by the MATLAB scripts.
 #### File: VSXsimulation.zip **Description:** Transmission sequence
 visualization and comparison using the simulated data from the Verasonics
 software package. * DW_vs_ryln_fieldhomogeneity.m: Load simulated
 transmission pattern of diverging waves (DW) versus ray-line (RyLn) method
 and evaluate the field homogeneity in each case. *
 fieldhomogeneity.m: Load simulated transmission pattern of diverging waves
 (DW), plane waves (PW), and converging waves (CW), and evaluate the
 transmission field homogeneity in each case. *
 sim_VLA_45Angle_60degree_TXmode-1_radius-100mm_matchFOV.mat: Simulation
 data generated by the Verasonics software package using 45 diverging waves
 with virtual source depth at 100mm and a steering range of +/- 30 degrees.
 * sim_VLA_45Angle_60degree_TXmode0_radius0mm_matchFOV.mat: Simulation data
 generated by the Verasonics software package using 45 plane waves with a
 steering range of +/- 30 degrees. *
 sim_VLA_45Angle_60degree_TXmode1_radius80mm_matchFOV.mat: Simulation data
 generated by the Verasonics software package using 45 converging waves
 with a focal depth of 80mm and a steering range of +/- 30 degrees. ####
 File: humanspine_(2).zip **Description:** Original and processed data of
 human spine images, along with the MATLAB scripts used for processing. *
 CF_DAS_comparison: Beamformed ultrasound data and processing script in
 MATLAB for comparison of the linear delay-and-sum (DAS) beamformer versus
 the nonlinear coherence-factor (CF)-based DAS beamformer, corresponding to
 results presented in Fig. 4 and Table. S2. * US_CTcomparison: Processed
 ultrasound data and CT data from volunteer#2 for ultrasound-CT
 co-registration analysis, as well as the 3D rendering in 3D Slicer. This
 corresponds to results presented in Fig.5 and Fig. S4. * volumnscans:
 Beamformed ultrasound data from a human volunteer volumetric scan. This
 corresponds to results presented in Fig. S5 and the supplementary movies.
 * volunteerimages: Beamformed ultrasound data from a human volunteer
 single-frame scan. This corresponds to results presented in Fig. 2, Fig.
 S2, and Fig. S3. #### File: spinephantom_(3).zip and spinephantom_(2).zip
 **Description:** Original and processed data of the spine phantom, along
 with the MATLAB scripts used for processing. This corresponds to results
 presented in Fig. 6 and Fig.7. Reconstructed ultrasound volume data are
 named as "Vol_CFDAS_scan_DW10mm_lateraldeg_centerallframes.mat". These files can be directly
 imported into the MATLAB workspace for visualization of the ultrasound
 volumetric scan. "SpineSegment.m" is the MATLAB script for
 segmenting the bony structure of the spine from the ultrasound volumetric
 data. Segmented bony structures are also provided in the MATLAB data
 format. Detailed instructions on how to use the MATLAB scripts can be
 found in each script. ## Code/software * MATLAB (2020b or later) * Prism
 Graphpad * 3D Slicer ## Human subjects data The human subject data
 (ultrasound images of lumbar and cervical spine from 7 healthy human
 volunteers) were only collected to analyze image quality. No information
 related to human subject identification were collected except the gender,
 age, and race. All participants explicitly consented to publish the
 de-identified data in the public domain.