Conventional Two-dimensional Imaging Research Articles

Nested Semi-Transparent Isosurface Simulated Volume-Rendering (NESTIS-VR) – An efficient on-device rendering approach for Augmented Reality headsets increasing surgeon confidence of kidney donor arterial anatomy

Background and objectiveVolume-renderings of computed tomography or magnetic resonance angiograms (MRAs) are routinely used by surgeons in the preoperative assessment of vascular anatomy in kidney donors. Stereoscopic headsets (OST-HMD) like Microsoft HoloLens allow intuitive interaction with three-dimensional content for more intuitive comprehension, but do not allow real-time ray-casting volume-rendering of medical volume datasets on-device due to computational limitations. MethodsWe introduce NEsted Semi-Transparent Isosurface Simulated Volume-Rendering (NESTIS-VR), as an on-device alternative to ray-casting volume-rendering and developed an application for HoloLens to render kidney donor MRAs with interactive control of fundamental rendering parameters. We compared NESTIS-VR with current standard pre-calculated 2D ray-cast volume-renderings in an observational study with 2 expert kidney transplant surgeons, measuring their confidence in pre-operatively assessing the kidney pedicle arterial anatomy in 20 potential donors. We also compared it against other 3D rendering techniques to understand which features contributed most to any improvements. ResultsReal-time stereoscopic three-dimensional (3D) NESTIS-VR in Augmented Reality significantly improves surgeons’ confidence compared with pre-calculated conventional two-dimensional (2D) ray-casting volume-rendered images (p = 0.0415/p = 0.00003). 2D non-stereoscopic NESTIS-VR was significantly superior to pre-calculated 2D ray-casting volume-rendered images for both surgeons (p = 0.044/p = 0.0003). Single isosurface 2D rendering was significantly superior than pre-calculated 2D volume-rendered images for one surgeon. There was no significant difference between binocular 3D display over 2D views with NESTIS-VR or between constrained and unconstrained vantage points for 2D viewing. ConclusionNESTIS-VR provides a new approach to rendering medical datasets in computationally limited OST-HMD headsets and significantly increases surgeons’ confidence of kidney donor arterial anatomy. The principal confidence benefit arises from providing surgeons interactive control over rendering parameters compared to pre-calculated renderings at preset parameters whilst rendering on-device and keeping the OST-HMD untethered from a workstation.

Near-field terahertz electro-optical imaging based on a polarization image sensor

Abstract This paper presents a hyperspectral microscopy system that offers two-dimensional (2D) measurement of the spectral phase and amplitude information of terahertz (THz) radiation without the need for raster scanning. To achieve this, a new THz imaging method is introduced, wherein the distribution of the THz electric field is spatially measured using the electro-optic effect with a commercial polarization image sensor. This method enables the direct measurement of polarization components, eliminating the need for the polarization optics usually required in conventional electro-optical imaging. The performance of this imaging method is compared with a conventional 2D imaging system based on a standard visible camera. Finally, the sub-wavelength resolution capabilities of this new sensor are demonstrated by imaging a sample in the near field.

Three-dimensional atomic insights into the metal-oxide interface in Zr-ZrO2 nanoparticles

Metal-oxide interfaces with poor coherency have specific properties comparing to bulk materials and offer broad applications in heterogeneous catalysis, battery, and electronics. However, current understanding of the three-dimensional (3D) atomic metal-oxide interfaces remains limited because of their inherent structural complexity and the limitations of conventional two-dimensional imaging techniques. Here, we determine the 3D atomic structure of metal-oxide interfaces in zirconium-zirconia nanoparticles using atomic-resolution electron tomography. We quantitatively analyze the atomic concentration and the degree of oxidation, and find the coherency and translational symmetry of the interfaces are broken. Atoms at the interface have low structural ordering, low coordination, and elongated bond length. Moreover, we observe porous structures such as Zr vacancies and nano-pores, and investigate their distribution. Our findings provide a clear 3D atomic picture of metal-oxide interface with direct experimental evidence. We anticipate this work could encourage future studies on fundamental problems of oxides, such as interfacial structures in semiconductor and atomic motion during oxidation process.

Microstructural changes in thermochemical heat storage material over cycles: Insights from micro-X-ray computed tomography

This paper studies the effect of successive (de)hydration cycles on the structure of potassium carbonate K2CO3·1.5H2O grains for low-temperature heat storage applications. Such structural changes are caused by exposure of the salt to water vapor or removal of water from it, accompanied by successive swelling and shrinkage. Understanding the material's internal structure is key to predicting its behaviour and optimizing its design. However, due to the simultaneous and persistent occurrence of structural changes and transport mechanisms throughout the process, gaining a complete understanding of the phenomenon can be challenging.Unlike conventional experimental approaches and two-dimensional imaging techniques used for porosity assessment, our study showcases the qualitative and quantitative alterations in the porosity and microstructure of potassium carbonate. This analysis is achieved by using Micro-X-ray computed tomography (Micro-CT). The study focuses on the impact of cycling on grain microstructure, investigating pore volume distribution, radial variation of pore sizes, and density of individual grains. It was noted that the porosity increased from 6.4 % to 19.7 % after seven cycles. Initially, we observed a greater number of pores in the core of the uncycled salt grain. However, after cycling, we noticed a more even distribution, with a higher number of pores in the outer region of the grain, which caused a radial change in porosity. Lastly, this research provides the intrinsic and apparent densities of both non-cycled and cycled potassium carbonate specimens.Micro-CT is a good tool for a better understanding of changes in thermochemical material at a structural level. Calculation of porosity provided a pathway to calculate apparent and intrinsic density. The demonstrated method can be used for a wide range of salt hydrates, enhancing the scope and applicability of this study in the field of low-temperature heat storage applications. Additionally, it gives the measuring parameter needed to calculate energy density and change in volume during the reaction.

Reliability of Conventional Two-Dimensional Magnetic Resonance Imaging for Diagnosing Extraforaminal Stenosis in Lumbosacral Transition

Reliability of Conventional Two-Dimensional Magnetic Resonance Imaging for Diagnosing Extraforaminal Stenosis in Lumbosacral Transition

Diagnostic, prognostic and clinical value of left ventricular radial strain to identify paradoxical septal motion in ventilated patients with the acute respiratory distress syndrome: an observational prospective multicenter study

BackgroundAcute cor pulmonale (ACP) is prognostic in patients with acute respiratory distress syndrome (ARDS). Identification of paradoxical septal motion (PSM) using two-dimensional echocardiography is highly subjective. We sought to describe feature-engineered metrics derived from LV radial strain changes related to PSM in ARDS patients with ACP of various severity and to illustrate potential diagnostic and prognostic yield.MethodsThis prospective bicentric study included patients under protective ventilation for ARDS related to COVID-19 who were assessed using transesophageal echocardiography (TEE). Transgastric short-axis view at mid-papillary level was used to visually grade septal motion, using two-dimensional imaging, solely and combined with LV radial strain: normal (grade 0), transient end-systolic septal flattening (grade 1), prolonged end-systolic septal flattening or reversed septal curvature (grade 2). Inter-observer variability was calculated. Feature engineering was performed to calculate the time-to-peak and area under the strain curve in 6 LV segments. In the subset of patients with serial TEE examinations, a multivariate Cox model analysis accounting for new-onset of PSM as a time-dependent variable was used to identify parameters associated with ICU mortality.ResultsOverall, 310 TEE examinations performed in 182 patients were analyzed (age: 67 [60–72] years; men: 66%; SAPSII: 35 [29–40]). Two-dimensional assessment identified a grade 1 and grade 2 PSM in 100 (32%) and 48 (15%) examinations, respectively. Inter-rater reliability was weak using two-dimensional imaging alone (kappa = 0.49; 95% CI 0.40–0.58; p < 0.001) and increased with associated LV radial strain (kappa = 0.84, 95% CI 0.79–0.90, p < 0.001). The time-to-peak of mid-septal and mid-lateral segments occurred significantly later in systole and increased with the grade of PSM. Similarly, the area under the strain curve of these segments increased significantly with the grade of PSM, compared with mid-anterior or mid-inferior segments. Severe acute cor pulmonale with a grade 2 PSM was significantly associated with mortality. Requalification in an upper PSM grade using LV radial strain allowed to better identify patients at risk of death (HR: 6.27 [95% CI 2.28–17.2] vs. 2.80 [95% CI 1.11–7.09]).ConclusionsIn objectively depicting PSM and quantitatively assessing its severity, TEE LV radial strain appears as a valuable adjunct to conventional two-dimensional imaging.

3D Orientation Imaging of Polymer Chains with Polarization-Controlled Coherent Raman Microscopy

Despite the ubiquity of three-dimensional (3D) anisotropic materials, their 3D molecular alignment cannot be measured using conventional two-dimensional (2D) polarization imaging. Here, we present images of the 3D angles of molecular orientations with submicrometer spatial resolution acquired through polarization-controlled coherent anti-Stokes Raman scattering microscopy. The hyperspectral Raman data of a polyethylene (PE) film were converted into images, showing the polymer chains' 3D angles and order parameters. The 3D orientation images of PE chains in ring-banded spherulites show that the azimuthal angles of the chains are perpendicular to the crystal growth direction, while the out-of-plane angles display limited-range oscillations synchronous with ring banding. The prevailing crystal growth model of fully twisting lamellae is inconsistent with the observed restricted oscillations of the out-of-plane direction, which are unobservable through conventional 2D projected imaging. This high-resolution, label-free, quantitative imaging of 3D molecular orientation can become a standard measurement tool for the microscopic structures of complex synthetic and biological materials.

Comparing image quality of five breast tomosynthesis systems based on radiologists' reviews of phantom data.

Previous studies have shown differences in technical image quality between digital breast tomosynthesis (DBT) systems. However, quantitative image quality measurements may not necessarily fully reflect the clinical performance of DBT. To study the subjective image quality of five DBT systems manufactured by Fujifilm, GE, Hologic, Planmed, and Siemens using phantom images. A TOR MAM test object with polymethyl methacrylate plates was imaged on five DBT systems from different vendors. Three DBT acquisitions were performed at mean glandular doses of 1.0 mGy, 2.0 mGy, and 3.5 mGy while maintaining a constant phantom set-up. Eight DBT acquisitions with different test plate positions and phantom set-up thicknesses were performed at clinically applied dose levels. Additionally, three conventional two-dimensional mammogram images were acquired with different phantom thicknesses. Six radiologists ranked the systems based on the visibilities of the targets seen in the phantom images. In the DBT acquisitions performed at comparable dose levels, one system differed significantly from all other systems in microcalcification scores. When using site-specific DBT protocols, significant differences were found between the devices for microcalcification, filament, and low-contrast targets. A strong correlation was observed between the reviewer scores and radiation doses in DBT acquisitions, whereas no such correlation was observed in the 2D acquisitions. In DBT acquisitions, dose level was found to be a major factor explaining image quality differences between the systems, regardless of other acquisition parameters. Most DBT systems performed equally well at similar dose levels.

Accelerated three-dimensional susceptibility weighted imaging of the whole spine of fetus at 3T

ObjectivesTo investigate the image quality and capability of generalized auto-calibrating partially parallel acquisition (GRAPPA) accelerated Three-dimensional (3D) susceptibility weighted imaging (SWI) of the whole spine at 3T. MethodsA total of 37 pregnant women (gestation age 22 to 39 weeks, average 29 ± 3 weeks) with suspected fetal vertebral anomalies by ultrasound (US) screening underwent 3.0T MR imaging with 3D SWI, conventional two-dimensional (2D) half-flourier acquisition single-shot turbo spin-echo (HASTE) and 3D true fast imaging with steady-state precession (True FISP). The acquisition time of each protocol was recorded. Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) were determined in representative interest regions of fetal thoracic vertebrae and compared among three pulse sequences. Two radiologists rated image quality independently in random order on a 5-point scale. Kappa coefficients were computed to assess inter-observer reliability. Receiver operating characteristic curves were generated, and the area under the curve (AUC) was used to compare the diagnostic performance of each protocol in vertebral deformities. ResultsThe acquisition time was 15 s for 3D-SWI and 17 s for 3D True FISP, significantly shorter than conventional HASTE (37 s; both P < 0.01).Of the three protocols, The SNR was highest on 3D True FISP, while the CNR was highest on 3D SWI. Visualization of all segments of the whole spine by 3D SWI was comparable with 3D True FISP. In contrast, 3D SWI and 3D True FISP depicted cervical and sacrococcygeal vertebrae better than HASTE. The weighted kappa statistic was 0.70–0.89 to evaluate the image quality of all segments of the whole spine, indicating good to excellent interobserver agreement. 3D SWI had the highest diagnostic performance for detecting fetal vertebral anomalies (AUC = 0.92). Conclusions3D-SWI is feasible for improved visualization of the whole fetal vertebral column and its congenital malformations with adequate image quality and high accuracy, thereby providing a supplementary method to conventional MR imaging.

Assessment of cardiovascular risk factors in obese women with HIV.

The risk of significant weight gain/obesity associated with recently adopted antiretroviral therapy (ART) has been shown to be particularly higher among the black race, and female gender compared to their male counterparts. Herein, we evaluated and compared subclinical CVD risk between apparently healthy obese (BMI ≥30kg/m2) and age matched normal BMI (BMI 18.5-24.9kg/m2) women with HIV (WWH) on ART. This was a hospital-based cross-sectional study of adult (≥18 years) WWH. Conventional two-dimensional echocardiography and doppler imaging parameters, lipid profile, and high sensitivity C-reactive protein (hsCRP) measures were compared between the two groups. Multivariable regression analysis was done to determine independent variables. A total of 60 WWH were evaluated, 30 participants in each group. The mean age of the participants and duration on ART was 36.26 ± 5.71 and 10.23 ± 5.04 (years) respectively. Measured hsCRP, total cholesterol, and low-density lipoproteins were significantly (p = 0.002, p = 0.044, and p = 0.016 respectively) elevated in the obese group. Obese WWH had higher left atrial diameter, left atrial volume, left atrial area, aortic diameter, left ventricular mass (LVM), left ventricular mass index (LVMI), intraventricular septum in systole/diastole, left ventricular posterior wall in diastole and systole (p < 0.001, p = 0.018, p = 0.004, p = 0.025, p < 0.001, p = 0.019/p < 0.001, p = 0.020, and p = 0.021 respectively). On multivariable regression analysis, the measured serum biomarker hsCRP and the echocardiographic variables LVM and LVMI were independently associated (p = 0.02, p = 0.001 and p = 0.022 respectively) with BMI. Obese WWH had higher biomarkers of CVDs and alterations in left ventricular structure that may increase their risk for adverse cardiovascular morbidity and mortality.

An Improved Technique for Single-Channel Video-SAR Based on Fractional Fourier Transform

In the field of synthetic aperture radar (SAR), a lot of researchers have tried to study an improved application beyond the conventional two-dimensional image. Video-SAR (ViSAR) is one of the hot issue in the SAR application. The main purpose of ViSAR is to monitor various targets in the area of interest in time order. It can offer video images to detect not only the fixed target but also the moving target. For the signal processing of ViSAR, this article introduces the improved performance by the Doppler shifting technique with fractional Fourier transform. And also, it shows that the proposed method can separate the unexpected signal of the moving target within each frame of single-channel ViSAR. Furthermore, the overall algorithm can increase efficiency and reliability in ViSAR processing. To verify the improvement of our method, we carry out the practical experiments by an X-band chirp pulse SAR system, mounted on an airplane.

Actuated Reflector-Based 3-D Ultrasound Imaging With Synthetic Aperture Focusing.

Three-dimensional (3D) ultrasound (US) imaging addresses the limitation in field-of-view (FOV) in conventional two-dimensional (2D) US imaging by providing 3D viewing of the anatomy. 3D US imaging has been extensively adapted for diagnosis and image-guided surgical intervention. However, conventional approaches to implement 3D US imaging require either expensive and sophisticated 2D array transducers or external actuation mechanisms to move a one-dimensional array mechanically. Here, we propose a 3D US imaging mechanism using actuated acoustic reflector instead of the sensor elements for volume acquisition with significantly extended 3D FOV, which can be implemented with simple hardware and compact size. To improve image quality on the elevation plane, we implemented the synthetic aperture focusing (SAF) method according to the diagonal geometry of the virtual element array in the proposed imaging mechanism for elevation beamforming. We first evaluated the proposed imaging mechanism and SAF with simulated point targets and cyst targets. Results of point targets suggested improved image quality on the elevation plane, and results of cysts targets demonstrated a potential to improve 3D visualization of human anatomy. We built a prototype imaging system with a 3D FOV of 38 mm (lateral) by 38 mm (elevation) by 50 mm (axial) and collected data in imaging experiments with phantoms. Experimental data showed consistency with simulation results. The SAF method enhanced quantifying the cyst volume size in the breast mimicking phantom compared to without elevation beamforming. These results suggested that the proposed 3D US imaging mechanism could potentially be applied in clinical scenarios.

Comparison of pedicle screw placement accuracy between two types of imaging support (Artis Zeego versus two-dimensional fluoroscopy): a cross-sectional observational study

BackgroundThe pedicle screw system is widely used in spine surgery, and it provides rigid fixation and leads to successful subsequent deformity correction and bony fusion. The standard imaging technique for pedicle screw insertion is two-dimensional images obtained from C-arm-type X-ray fluoroscopy. Artis Zeego is an emerging intraoperative imaging technique that can provide conventional two-dimensional fluoroscopic images and rapid three-dimensional fluoroscopic computed tomography reconstruction imaging. The aim of this study is to compare the insertion accuracies of PS placement using Artis Zeego and conventional 2D X-ray fluoroscopy.MethodsIn this study, we retrospectively reviewed the postoperative images of thoracolumbar fusion patients who underwent surgery using pedicle screws between 2013 and 2018. Pedicle screw malplacement was assessed using a four-grade classification by Rao et al. Misplacement rates were compared between pedicle screws assisted with Artis Zeego and two-dimensional fluoroscopy.ResultsA total of 1107 pedicle screws in 153 patients were inserted using Artis Zeego, and 427 pedicle screws in 80 patients were inserted using fluoroscopy. The overall perforation rate was 4.2% (46 perforations of 1106 pedicle screws) in the Artis Zeego group and 7.7% (33 perforations of 427 pedicle screws) in the fluoroscopy group. In the Artis Zeego group, 43 (3.9%) screws were classified as grade 1, and three (0.3%) screws were classified as grade 2. In the fluoroscopy group, 21 (4.9%) screws were classified as grade 1, 10 (2.3%) screws were classified as grade 2, and 2 (0.5%) screws were classified as grade 3. The use of Artis Zeego was associated with a significantly lower screw malplacement rate than was the use of fluoroscopy (p < 0.001).ConclusionsOur results demonstrated that pedicle screw placement with Artis Zeego was associated with a lower malplacement rate than was conventional two-dimensional fluoroscopy. No severe malplacement was observed in the Artis Zeego group. Thus, Artis Zeego could be a good option for improving pedicle screw accuracy.

A preliminary study on the evaluation of left atrial function of rheumatoid arthritis by two dimensional speckle tracking imaging

To evaluate the changes of left atrial (LA) geometry and function in patients with rheumatoid arthritis (RA) by conventional echocardiography and two-dimensional speckle tracking imaging (2D-STI). We enrolled 46 RA patients with a duration of < 5 years as Group I, 40 RA patients with a duration of ≥ 5 years as Group II, and 40 normal subjects as the control group. Conventional echocardiography was conducted to measure traditional parameters. The LA strain during reservoir phase (LASr), LA strain during conduit phase (LAScd), LA strain during contraction phase (LASct), and LA global longitudinal strain (LAGLS) were obtained from 2D-STI. Related ultrasound results were compared. The LASct was significantly higher in Group I than in control group (P < 0.05). The LASr, LAScd, and LAGLS were significantly lower in Group I than in control group (all P < 0.05). The LASr, LAScd, LASct, and LAGLS were significantly lower in Group II than in control group and Group I (all P < 0.05). The function of LA impaired in RA patients, and the impairment aggravated with the clinical course of RA patients. 2D-STI technology can early and accurately evaluate the LA function of RA patients by evaluating LASr, LAScd, LASct, and LAGLS.

Intraoperative holography navigation using a mixed-reality wearable computer during laparoscopic cholecystectomy

BackgroundMixed-reality technology, a new digital holographic image technology, is used to present 3-dimensional (3D) images in the surgical space using a wearable mixed-reality device. This study aimed to assess the safety and efficacy of laparoscopic cholecystectomy using a holography-guided navigation system as an intraoperative support image.In this prospective observational study, 27 patients with cholelithiasis or mild cholecystitis underwent laparoscopic cholecystectomy between April 2020 and November 2020. Nine patients underwent laparoscopic cholecystectomy with 3D models generated by a wearable mixed-reality device (laparoscopic cholecystectomy with 3D models) and 18 underwent laparoscopic cholecystectomy with conventional two-dimensional images (laparoscopic cholecystectomy with 2D images) as surgical support images. Surgical outcomes such as operative time, blood loss, and perioperative complication rate were measured, and a four-item questionnaire was used for subjective assessment. All surgeries were performed by a mid-career and an experienced surgeon. ResultsMedian operative times of laparoscopic cholecystectomy with 3-dimensional models and 2-dimensional images were 74.0 and 58.0 minutes, respectively. No intraoperative blood loss or perioperative complications occurred. Although the midcareer surgeon indicated that laparoscopic cholecystectomy with 3-dimensional models was “normal” or “easy” compared with 2-dimensional images in all cases, the experienced surgeon rated 3-dimensional models as more difficult in 3 (33%) of 9 cases. ConclusionThis study provides evidence that laparoscopic cholecystectomy with 3-dimensional models is feasible. However, the efficacy of laparoscopic cholecystectomy with 3-dimensional models may depend on the surgeon’s experience, as indicated by the different ratings provided by the surgeons.

Right and left ventricular function and flow quantification in pediatric patients with repaired tetralogy of Fallot using four-dimensional flow magnetic resonance imaging

BackgroundTo assess the accuracy and reproducibility of right ventricular (RV) and left ventricular (LV) function and flow measurements in children with repaired tetralogy of Fallot (rTOF) using four-dimensional (4D) flow, compared with conventional two-dimensional (2D) magnetic resonance imaging (MRI) sequences.MethodsThirty pediatric patients with rTOF were retrospectively enrolled to undergo 2D balanced steady-state free precession cine (2D b-SSFP cine), 2D phase contrast (PC), and 4D flow cardiac MRI. LV and RV volumes and flow in the ascending aorta (AAO) and main pulmonary artery (MPA) were quantified. Pearson’s or Spearman’s correlation tests, paired t-tests, the Wilcoxon signed-rank test, Bland–Altman analysis, and intraclass correlation coefficients (ICC) were performed.ResultsThe 4D flow scan time was shorter compared with 2D sequences (P < 0.001). The biventricular volumes between 4D flow and 2D b-SSFP cine had no significant differences (P > 0.05), and showed strong correlations (r > 0.90, P < 0.001) and good consistency. The flow measurements of the AAO and MPA between 4D flow and 2D PC showed moderate to good correlations (r > 0.60, P < 0.001). There was good internal consistency in cardiac output. There was good intraobserver and interobserver biventricular function agreement (ICC > 0.85).ConclusionsRV and LV function and flow quantification in pediatric patients with rTOF using 4D flow MRI can be measured accurately and reproducibly compared to those with conventional 2D sequences.

Optical signal detection in turbid water using multidimensional integral imaging with deep learning.

Optical signal detection in turbid and occluded environments is a challenging task due to the light scattering and beam attenuation inside the medium. Three-dimensional (3D) integral imaging is an imaging approach which integrates two-dimensional images from multiple perspectives and has proved to be useful for challenging conditions such as occlusion and turbidity. In this manuscript, we present an approach for the detection of optical signals in turbid water and occluded environments using multidimensional integral imaging employing temporal encoding with deep learning. In our experiments, an optical signal is temporally encoded with gold code and transmitted through turbid water via a light-emitting diode (LED). A camera array captures videos of the optical signals from multiple perspectives and performs the 3D signal reconstruction of temporal signal. The convolutional neural network-based bidirectional Long Short-Term Network (CNN-BiLSTM) network is trained with clear water video sequences to perform classification on the binary transmitted signal. The testing data was collected in turbid water scenes with partial signal occlusion, and a sliding window with CNN-BiLSTM-based classification was performed on the reconstructed 3D video data to detect the encoded binary data sequence. The proposed approach is compared to previously presented correlation-based detection models. Furthermore, we compare 3D integral imaging to conventional two-dimensional (2D) imaging for signal detection using the proposed deep learning strategy. The experimental results using the proposed approach show that the multidimensional integral imaging-based methodology significantly outperforms the previously reported approaches and conventional 2D sensing-based methods. To the best of our knowledge, this is the first report on underwater signal detection using multidimensional integral imaging with deep neural networks.

Novel Three-Dimensional Bladder Reconstruction Model from B-Mode Ultrasound Image to Improve the Accuracy of Bladder Volume Measurement

Traditional bladder volume measurement from B-mode (two-dimensional) ultrasound has been found to produce inaccurate results, and thus in this work we aim to improve the accuracy of measurement from B-mode ultrasound. A total of 75 electronic medical records including ultrasonic images were reviewed retrospectively from 64 patients. We put forward a novel bladder volume measurement method, in which a three-dimensional (3D) reconstruction model was established from conventional two-dimensional (2D) ultrasonic images to estimate the bladder volume. The differences and relationships were analyzed among the actual volume, the traditional estimated volume, and the new reconstruction model estimated volume. We also compared the data in different volume groups from small volume to high volume. The mean actual volume is 531.8 mL and the standard deviation is 268.7 mL; the mean percentage error of traditional estimation is −28%. In our new bladder measurement method, the mean percentage error is −10.18% (N = 2), −4.72% (N = 3), −0.33% (N = 4), and 2.58% (N = 5). There is no significant difference between the actual volume and our new bladder measurement method (N = 4) in all data or the divided four groups. The estimated volumes from the traditional method or our new method are highly correlated with the actual volume. Our data show that the three-dimensional bladder reconstruction model provides an accurate measurement from conventional B-mode ultrasonic images compared with the traditional method. The accuracy is seen across different groups of volume, and thus we can conclude that this is a reliable and economical volume measurement model that can be applied in general software or in apps on mobile devices.

Review of the radiographic modalities used during dental implant therapy - A narrative

The introduction of digital x-ray receivers which replaced conventional films was a significant radiographic development that is commonly used in daily dental practice. Dental implant therapy (DIT) is a sought after dental therapeutic intervention and dental radiography is an essential component contributing to the success of treatment. Dental radiographs taken in daily practice are generally conventional two-dimensional images and/or three-dimensional images. Ideally, the choice of radiographic technique should be determined after a thorough clinical examination and comprehensive consideration of the advantages, indications, and drawbacks. Digital three-dimensional modalities that have emerged over the last decade have been incorporated into DIT with the assumption that treatment outcomes will be improved. These modalities are constantly being reassessed and improved but there is a paucity of published information regarding the assessment of variables such as dosages and dimensional accuracy, suggesting that further research in these matters is necessary. This is crucial in order to obtain evidence-based information that may influence future radiographic practices. In this narrative, the authors present the most commonly used dental radiographic modalities currently used in DIT.

The impact of Digital Breast Tomosynthesis on BIRADS categorization of mammographic non-mass findings

ABSTRACT Introduction: Mammography is the most used breast screening tool and was proven to reduce breast-cancer-associated mortality. The estimated sensitivity of mammography varies between 77% and 95%; however, sensitivity could be 26% lower in dense breasts than in entirely fatty breasts. The ability to represent the complex 3D breast architecture and early changes in anatomical structures in a 2D view is the biggest challenge for mammography. In Digital Breast Tomosynthesis (DBT), tomographic images are reconstructed from multiple projections acquired from different angles. This technique allows the generation of 3D data, reduction of tissue overlap and allows better evaluation of masses, architectural distortion, and asymmetries compared with conventional two-dimensional mammographic images. Objective: To evaluate the impact of Digital Breast Tomosynthesis on BIRADS categorization of mammographic non-mass findings. Methods: Prospective cohort for 180 women with mammographic non-mass findings who presented to Alexandria University Radio diagnosis Department either for screening or diagnostic purposes between July 2019 and August 2020 with mean age 51.44 ± 10.67 . Digital breast tomosynthesis and ultrasound was done for all patients. Lesions were evaluated on DM; DBT alone then combined DBT & DM. Comparison of results according to changes in BIRADS, diagnostic performance using histopathology as gold standard. Results: 208 non-mass findings were detected by conventional mammography (104 asymmetry, 35 architectural distortion, 69 micro calcifications), Tomosynthesis reduced the BIRADS 3 count by 32%, upgraded the count of BIRADS 4 lesions by 11.4% while upgraded the BIRADS 2 by 18.9% with consequent improvement of sensitivity and specificity, PPV, NPV and accuracy to 96%, 95%, 94%,97%, and 95.6%. Conclusion: Combined FFDM and DBT improved the diagnostic performance in evaluation of non-mass findings and proper BIRADS categorization.