Inferior Images Research Articles

Recognition of Hindi and Bengali Handwritten and Typed Text from Images using Tesseract on Android Platform

The concept of digitization has marked a revolution in the area of data conversion, data storage and data sharing by converting non-editable typographic & handwritten text into editable electronic text. Though numerous such works have been carried out across the world in various languages using Optical Character Recognition (OCR), satisfactory output has been observed only in a few languages. This paper is an endeavor towards taking a step ahead in the digitization of two of the most extensively spoken languages in the Indian sub-continent – Hindi and Bengali - using Google’s open source OCR Engine, Tesseract. Working on the scripts of these two languages of Brahmi origin has its own challenges owing to their varied traits of character segmentation and word formation. Here, the training of Tesseract with data sets of Hindi and Bengali typographic and handwritten characters has been integrated with an inimitable pre-processing stage involving input image customization and image augmentation that significantly enhances the image quality allowing Tesseract to offer more accurate results, especially in cases of handwritten texts and obscure images. Besides, it also incorporates the features of English translation and text to speech translation which render their significance among the non-natives and visually impaired mass. The focal idea of this paper has been to reach out to an extended mass by enabling digitization on the Android platform. Comparative analysis carried out on three distinctive parameters - on images with typographic texts, handwritten texts and on inferior quality images - shows that the paper, to a certain extent, does succeed in projecting superior output in at least two cases as compared to the most consistent Android application of today’s time.

Lung ultrasound for early diagnosis of postoperative need for ventilatory support: a prospective observational study.

Pulmonary complications have a significant impact on morbidity and mortality in patients after major surgery. Lung ultrasound can be used at the bed-side, and has gained widespread acceptance in the intensive care unit. We conducted a prospective study to evaluate whether lung ultrasound could be used as a predictive marker for postoperative ventilatory support in high-risk surgical patients. We included 109 patients admitted to the intensive care unit while having mechanical ventilation of the lungs following major surgery. The PaO2 /FI O2 ratio was calculated on admission and an ultrasound examination performed, including: lung ('lung ultrasound score', number of consolidated lung areas); cardiac (mitral flow); and inferior vena cava imaging (diameter and respiratory variation). Respiratory outcomes included: the need for ventilation support (mechanical ventilation, non-invasive ventilation or high-flow nasal cannula oxygen therapy); acute respiratory distress syndrome; cardiogenic pulmonary oedema; and early or late pulmonary infection. Patients with a lung ultrasound score ≥ 10 had a lower PaO2 /FI O2 ratio, and needed more postoperative ventilatory support, than patients with lung ultrasound score < 10. Twenty patients had acute respiratory distress syndrome, and 14 had cardiogenic pulmonary oedema. The presence of ≥ 2 areas of consolidated lung was associated with a lower PaO2 /FI O2 ratio, postoperative ventilatory support, longer intensive care stay and episodes of ventilator-associated pneumonia requiring antibiotics. Our results suggest that at intensive care unit admission, lung ultrasound scoring and detection of atelectasis can predict postoperative pulmonary outcomes after major visceral surgery, and could enhance bed-side decision making.

Bedside Ultrasound in Fluid Assessment: Correlation of Internal Jugular and Subclavian Vein Diameter Variation with Invasive Right Heart Catheterization

Introduction Accurate estimation of fluid status is of paramount importance in patients with heart failure. Frequent invasive right heart catheterization is not feasible and accurate inferior vena cava imaging requires training. Internal jugular vein (IJV) and subclavian vein (SCV) could provide easier alternatives. Methods Patients scheduled to undergo right heart catheterization were prospectively enrolled in the study. Body surface area (BSA) was noted. Patient was positioned flat supine. IJV was imaged at the apex of the right sternocleidomastoid muscle and SCV was imaged at the lateral third of the right clavicle. Using M-mode on a portable ultrasound machine, the maximum (Dmax) and minimum (Dmin) anteroposterior diameters were noted during normal breathing, without applying any external pressure. Respiratory collapsibility was assessed with sniff. Respiratory variation in diameter (RVD) was calculated as: [(Dmax - Dmin)/ Dmax] and expressed as percent. Diameter variation index (DVI) was calculated as: (Dmax - Dmin)/ BSA. Results Total 72 patients enrolled with mean age 61 ± 14 years, mean BSA 2 ± 0.3m2, left ventricular (LV) ejection fraction 45 ± 20%. SCV could not be imaged in 7 patients. Elevated right atrial [RA] pressure (>=10mmHg) patients showed less RVD with resting respiration (14 vs. 41% for IJV and 24% vs. 46% for SCV, p= 0.01) and less likely to show total collapsibility with sniff (table 1). Similarly, DVI was lower with high RA pressure. Dmax alone did not correlate for SCV (table 1). For RA pressure >=10mmHg, lack of IJV collapsibility with sniff had a sensitivity of 84% and ROC area 0.75. Dmax >1cm and RVD =10mmHg. Conclusion There is a positive correlation between fluid status with IJV and SCV diameters (absolute and respiratory variation). The diagnostic performance of these veins was similar to inferior vena cava, but easier to perform.

MRI-guided percutaneous needle biopsy with 1.2T open MRI: study protocol for a prospective feasibility study (SCIRO-1701).

ABSTRACTThere has been growing interest in magnetic resonance imaging (MRI)-guided interventional procedures such as percutaneous needle biopsy. Although open MRI is preferable for MRI-guided procedures in terms of patient accessibility, its inferior imaging capability due to lower field strength is a substantial limitation. In this situation, the high-field (1.2T) open MRI has recently become available. This novel MRI system is expected to provide excellent image quality as well as good patient accessibility, potentially contributing to safe and accurate device manipulation. This trial is designed to investigate the feasibility of MRI-guided percutaneous needle biopsy with this system. Patients with lesions needing percutaneous needle biopsy for pathological diagnosis are included. The enrollment of ten patients is intended. The primary endpoint of this study is the feasibility of biopsy needle insertion under real-time MR-fluoroscopy guidance based on the presence of the notch of the biopsy needle within the target lesion. The secondary endpoints are adverse events, device failures, and success of specimen acquisition. Once the feasibility of MRI-guided biopsy with 1.2T open MRI is validated by this study, it may potentially encourage widespread use of MRI-guidance for biopsy procedures. Furthermore, it may lead to development of the other MRI-guided interventional procedures using this MRI system.

Compensation method of multiple‐channel amplitude and phase errors for MIMO imaging radar

Multiple-input multiple-output (MIMO) radar plays a more and more important role in radar imaging, target detection, and other fields owing to its unique array structure. Transmitting orthogonal signals by different transmitters, a MIMO radar can significantly enhance the azimuth resolution. It forms multiple observation channels from different transmit and receive array elements, achieving an equivalent large aperture in azimuth direction. However, the amplitude and phase errors in each channel are introduced, which will lead to inferior imaging performance of the system, especially in azimuth direction. To solve this problem, a method to estimate the amplitude and phase errors of each channel based on a strong scatterer is proposed here. Peak amplitude of one-dimensional range between channel is estimated using constrained least square (CLS) based on ideal point target characteristics. It proved to be valid by a simulation and an imaging experiment.

Internal medicine residents' point-of-care ultrasound skills and need assessment and the role of medical school training.

Introduction: Point-of-care-ultrasound (POCUS) as a useful bedside tool is growing. Few studies have examined residents’ attitude towards POCUS or compared POCUS image interpretation skills between residents with and without POCUS training in medical school.Material and Methods: We distributed an anonymous survey and image interpretation test to assess residents’ attitude towards POCUS, confidence, and skills in interpreting POCUS images and videos. Using independent samples t-tests, we compared mean confidence levels and test scores between residents with and without prior POCUS training.Results: Fifty-two residents responded to survey (response rate 68%) and 59 took the image interpretation test (77%). Most residents (90%) reported being interested in POCUS. Residents with prior POCUS training (n=13) were either PGY-1 (9) or PGY-2 (4). No PGY-3 resident had prior training. Most residents (83%) thought POCUS could be extremely useful in the inpatient setting compared to 29% for outpatient setting. PGY-1 residents with prior training had a higher mean confidence level than PGY-1 residents without prior training, but the difference was not statistically significant (3.26 vs 2.64; p=0.08). PGY-1 with prior training had a mean confidence level that was close to that of PGY-3 residents. PGY-1 residents with prior training scored significantly higher than PGY-1 residents without prior training in image interpretation test (10.25 vs 7; p=0.01). Residents felt most confident in interpreting inferior vena cava images (mean 3.7; max. 5), which also had the highest score in image interpretation test (correct response rate of 88%).Conclusion: Our residents seem very interested in POCUS. PGY-1 residents with prior POCUS training in medical school seem to have higher confidence in their POCUS skills than PGY-1 residents without prior training and outperformed them in image interpretation test. The study is very instructive in building our future POCUS curriculum for residents.

Comparison of vector velocity imaging and three-dimensional speckle tracking echocardiography for assessment of left ventricular longitudinal strain in hypertrophic cardiomyopathy.

Background: Vector velocity imaging (VVI) is a two-dimensional wall motion tracking method that can measure cardiac mechanics in hypertrophic cardiomyopathy (HCM). 3D-speckle tracking echocardiography (3D-STE) has been proven to be superior to conventional measures in assessment of LV function. The aim of this study was to compare the two technologies in the assessment of LV longitudinal strain (LS) in HCM patients.Methods: A total of 50 patients with HCM were investigated using VVI and 3D-STE in same setting. 3D-STE allows obtaining longitudinal, circumferential, radial and area strains (AS). Values of longitudinal strain (LS) and AS by 3D-STE were compared to VVI- derived analyses. Thereafter, VVI-LS values were correlated with LV phenotype. Last, the variability of VVI versus 3DE strain measurements as well as recorded time of analysis was assessed.Results: The absolute value of 3D-STE LS and AS is significantly higher than VVI-LS (P < 0.0001). VVI provided complete longitudinal LV strain information, similar to 3D-STE. There is excellent agreement between the two technologies-derived values, however, a greater number of segments could be analyzed using VVI (94.7%), compared with 3DE (62.1%). Despite VVI being more time consuming, VVI-LS is more correlated to LV mass index, mitral regurgitation severity and functional class when compared with 3D-STE LS and AS.Conclusions: VVI is a feasible modality for assessing LV longitudinal strain. Although VVI agreed well with 3D-STE for most of regional and global LS, a better correlation was found between VVI-LS and HCM phenotype. It is hypothesized that this discrepancy originates from the inferior imaging quality using 3D tracking algorithms.

A Novel Finger-Vein Recognition Based on Quality Assessment and Multi-Scale Histogram of Oriented Gradients Feature

Inferior finger vein images would seriously alter the completion of recognition systems. A modern finger-vein recognition technique combined with image quality assessment is developed to overcome those drawbacks. By the quality assessment, this article can discard the inferior images and retain the superior images which are then transferred to the recognition system. Different from previous methods, this article assesses the quality features of the image for the purpose of distinguishing whether the image contains rich and stable vein characteristics. In light of this purpose, the quality assessment is implemented: first, the finger vein image is automatically annotated; second, the finger vein image is cut into image blocks to expand the training set; third, the average quality score of multiple image blocks from an image is the final quality score of the image in the course of testing. Next, the Histogram of Oriented Gradients (HOG) features are extracted from the four transformed high-quality sub-images, whose features are cascaded into the multi-scale HOG feature of an image. Finally, two modules, the quality assessment module using Convolutional Neural Networks (CNN) and finger vein recognition module which make full use of multi-scale HOG, are perfectly combined in this article. The test results have demonstrated that light-CNN can identifies inferior and superior images accurately and the multi-scale HOG is feasible and effective. What's more, this article can see the robustness of this combined method in this article.

Influence of hypersonic turbulence in plasma sheath on synthetic aperture radar imaging

On the basis of the fractal theory and measurements of hypersonic turbulence, the spectral index, and two-dimensional (2D) power spectrum of the refractive index fluctuation are derived, and the 2D band-limited Weierstrass fractal function is applied to simulate the refractive index fluctuation in hypersonic turbulence. Thus, the impact of hypersonic turbulence on synthetic aperture radar (SAR) imaging system is simulated using the fractal phase screen method. Results show that the resolution of SAR imaging is severely deteriorated under the influence of hypersonic turbulence. The phase error caused by the turbulence microstructures in the plasma sheath becomes more apparent with the increase in the fractal dimension of the hypersonic turbulence. The larger Reynolds number associated with the hypersonic turbulence results in a more evident microstructure fluctuation and inferior imaging quality. Furthermore, when an aircraft flies at high speed, the azimuth focus is considerably sensitive to the turbulence microstructure along the direction of flow field. Consequently, hypersonic turbulence in the plasma sheath has a significantly larger effect on the azimuth than on the range in point-target imaging.

Effect of the Fe/Ba Ratio and Sintering Temperature on Microstructure and Magnetic Properties of Barium Ferrites Prepared by Hydrothermal Method

Magnetoplumbite-type (M-type) hexagonal barium ferrite particles were synthesized by a hydrothermal method. The structure and magnetic properties of barium ferrites were investigated systematically, which indicated that the ratio of Fe/Ba (RF/B) and sintering temperature have an important effect on structure and performance. Phase composition, micro-morphology, and magnetic properties of the particles were investigated by X-ray powder diffraction (XRD) analysis, scanning electron microscopy (SEM), and vibrating sample magnetometry (VSM). When the ratio of Fe/Ba (RF/B) is even low or high, inferior images of XRD could be attained with certain impurities. When RF/B = 8, the single phase could be obtained without impurities. Micro-morphology of the particles exhibits the uniform plane hexagonal structures of nano-sized M-type ferrites when sintered at 800 °C. Saturation magnetization (M s) reaches the maximum value at RF/B = 7 (M s = 45.07 emu/g). The value of coercivity (H c) increases with the growth of RF/B, and H c is up to 6207 Oe when RF/B = 7. The effect of RF/B and temperature on magnetization (M s) and coercivity (H c) was studied in this paper.

Comparison of strategies for grading retinal images of premature infants for referral warranted retinopathy of prematurity

To determine the accuracy of identifying referral-warranted retinopathy of prematurity (RW-ROP, defined as any zone I ROP, stage 3 or worse, or plus disease) from retinal image sets using three grading protocols: a single optic disk-centered image, a set of 3 horizontal images, and a 5-image set. In this secondary analysis of images from the e-ROP study, a weighted sample of 250 image sets from 250 infants (125 with RW-ROP and 125 without RW-ROP) was randomly selected. The sensitivities and specificities for detecting RW-ROP and its components from a single disk center image, along with nasal and temporal retinal images, were calculated and compared with the e-ROP grading of RW-ROP of all 5 retinal images (disk center and nasal, temporal, superior, and inferior retinal images). RW-ROP was identified with a sensitivity of 11.2% (95% CI, 6.79%-17.9%) using a single disk center image, with a sensitivity of 70.4% (95% CI, 61.9%-77.9%) using 3 horizontal images, and a statistically higher sensitivity of 82.4% (95% CI, 75.0%-89.0%) using all 5 images (P=0.002). The specificities were 100%, 86.4%, and 90.4%, respectively. For grading using 3 horizontal images, sensitivity was 14.3% for plus disease, 25% for zone I ROP, and 71.2% for stage 3 or worse compared to 40.8%, 50%, and 79.8% for grading using 5-image sets, respectively. Both a single, disk-centered, posterior pole image and 3 horizontal images were less effective than a 5-image set in determining the presence of RW-ROP on qualitative grading by trained readers.

Preclinical evaluation of [(68)Ga]NOTA-pentixafor for PET imaging of CXCR4 expression in vivo-a comparison to [(68)Ga]pentixafor.

BackgroundDue to its overexpression in a variety of tumor types, the chemokine receptor 4 (CXCR4) represents a highly relevant diagnostic and therapeutic target in nuclear oncology. Recently, [68Ga]pentixafor has emerged as an excellent imaging agent for positron emission tomography (PET) of CXCR4 expression in vivo. In this study, the corresponding [68Ga]-1,4,7-triazacyclononane-triacetic acid (NOTA) analog was preclinically evaluated and compared to the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) parent compound [68Ga]pentixafor.MethodsNOTA-pentixafor was synthesized by combining solid and solution-phase peptide synthesis. The CXCR4 receptor affinities of [68Ga]pentixafor and [68Ga]NOTA-pentixafor were determined in competitive binding assays using the leukemic CXCR4-expressing Jurkat T-cell line and [125I]FC131 as the radioligand. Internalization and cell efflux assays were performed using CXCR4-transfected Chem-1 cells. Small-animal PET and biodistribution studies were carried out using Daudi-tumor bearing SCID mice.Results[68Ga]NOTA-pentixafor showed a 1.4-fold improved affinity towards CXCR4 (IC50). However, internalization efficiency into CXCR4+-Chem-1 cells was substantially decreased compared to [68Ga]pentixafor. Accordingly, small-animal PET imaging and biodistribution studies revealed a 9.5-fold decreased uptake of [68Ga]NOTA-pentixafor in Daudi lymphoma xenografts (1.7 ± 0.4 % vs 16.2 ± 3.8 % ID/g at 90 min p.i.) and higher levels of non-specific accumulation, primarily in the excretory organs such as the liver, intestines, and kidneys (2.3 ± 0.9 % vs 2.0 ± 0.3 % ID/g, 1.9 ± 0.8 % vs 0.7 ± 0.2 % ID/g, and 2.7 ± 1.1 % vs 1.7 ± 0.9 % ID/g, respectively).ConclusionsDespite enhanced CXCR4-affinity in vitro, the [68Ga]NOTA-analog of pentixafor showed reduced CXCR4 targeting efficiency in vivo. In combination with enhanced background accumulation, this resulted in significantly inferior PET imaging contrast, and thus, [68Ga]NOTA-pentixafor offers no advantages over [68Ga]pentixafor.

Automated Breast Ultrasound: Dual-Sided Compared with Single-Sided Imaging

The design and performance of a mammographically configured, dual-sided, automated breast ultrasound (ABUS) 3-D imaging system are described. Dual-sided imaging (superior and inferior) is compared with single-sided imaging to aid decisions on clinical implementation of the more complex, but potentially higher-quality dual-sided imaging. Marked improvement in image quality and coverage of the breast is obtained in dual-sided ultrasound over single-sided ultrasound. Among hypo-echoic masses imaged, there are increases in the mean contrast-to-noise ratio of 57% and 79%, respectively, for spliced dual-sided versus superior or inferior single-sided imaging. The fractional breast volume coverage, defined as the percentage volume in the transducer field of view that is imaged with clinically acceptable quality, is improved from 59% in both superior and inferior single-sided imaging to 89% in dual-sided imaging. Applying acoustic coupling to the breast requires more effort or sophisticated methods in dual-sided imaging than in single-sided imaging.

Training retinal imagers for retinopathy of prematurity (ROP) screening

To report the training/certification process of nonphysician imagers, image quality, and factors that affected image quality in the National Eye Institute sponsored multicentered e-ROP study. Nonphysician imagers underwent rigorous training and certification in obtaining retinal images, with attention to clarity, focus, and optic disk placement. Image readers measured pupil size in pupil image and graded posterior pole, temporal, nasal, superior, and inferior retinal images and classified them as good, adequate, poor, or missing. Good and adequate images were deemed acceptable. In 4,003 image sessions of 1,257 infants, 3,453 (86.8%) were complete. Of 39,550 retinal images, 91.7% had acceptable quality, 5.6% poor, and 2.7% were missing. Inadequate pupil dilation negatively affected acceptable image quality: 54% acceptable images for pupil <5mm versus 93% for >6mm(P<0.0001). When ventilatory equipment obstructed access to imaged infant, the percent of acceptable image quality decreased: 94% for no support versus 66.6% for oscillatory ventilation (P<0.0001). Acceptable image quality rates improved from 87% to 90% (P=0.03) from first 6months to last 6months at low patient volume centers, while high patient volume centers remained stable at 95%. Nonphysicians successfully obtained acceptable quality images for ROP evaluation. Skills improved with experience. Image quality was negatively affected by inadequate pupil dilation and the presence of obstructive ventilatory equipment.

P5. Acute versus chronic lesion mapping: Methodological considerations from a study of arm motor functions

The method of lesion analysis is a tool widely used in cognitive neuroscience to conduct group studies with stroke patients associating cognitive dysfunctions with brain lesions. Although modern statistical lesion analysis (voxel wise lesion symptom mapping, VLSM) is an established tool there is still a lively debate about the time between stroke onset, neuroimaging and the assessment of cognitive functions. There are several reasons supporting acute/subacute or chronic neuroimaging or functional assessment. Performing lesion mapping in acute stages avoids the influences of uncontrollable variables such as individual rehabilitative interventions and resources obviously biasing data collection in the chronic phase. Further, deficits occurring only in the acute phase will be overlooked. On the other hand, high resolution images at a chronic stage when acute consequences of brain lesions, such as tissue swellings, have decreased represent a more accurate method of lesion localization than qualitative inferior clinical imaging. The present study aimed to investigate how post-stroke time of structural imaging and functional assessment may influence the results of lesion studies. We compared the results of anatomical and clinical data in acute versus chronic stages after stroke. Therefore, 55 patients were scanned in acute ( 4 months post stroke) stages after stroke with various neuroimaging techniques (CT, T2FLAIR, DWI, T1). As a functional measure motor deficits were assessed using BMRC (British medical research council) scores of (upper) limbs in acute and chronic stages. With established knowledge about the neuronal substrate of motor functions we were able to assess the validity of either method - acute and chronic lesion mapping. A subsample of patients ( n = 30) was scanned in the chronic phase with high-resolution MR techniques (T1, T2FLAIR), while from the other patients only CT or clinical MR scans were available. Normalized lesion maps from every patient and time point were compared intraindividually. Additionally, for the subsample of patients with high-resolution chronic imaging comparisons between T1 and T2FLAIR scans were conducted. For all conditions (chronic vs. acute, T1 vs. T2FLAIR) VLSM analyses were performed and the results were compared to known anatomy of motor functions. A preliminary data analysis demonstrated that acute and chronic/T1 and T2FLAIR scans differed significantly: chronic lesion maps drawn on T2FLAIR images tended to overestimate, chronic T1 scans to underestimate acute lesion size. We further observed obvious mislocalizations of chronic periventricular lesions through projection of the normalized lesion map onto a standard brain template. The VLSM analyses revealed different functional results depending on time point and image modality. However, the acute lesion approach showed the most accurate mapping of motor functions in the brain. We suspect that typical morphological changes over time cause a regional bias of chronic lesion maps. Especially regions in close vicinity to the ventricles may cause vast errors in lesion localization. Further, it is to assume that deficits associated with a lesion decreased/vanished due to regular neuronal reorganization processes or rehabilitative interventions. This clearly biased the measurement of behavioral in the chronic phase. These results suggest a preferential use of acute structural neuroimaging data for the method of lesion analysis.

Entry zone of iliac screw fixation to maintain proper entry width and screw length.

To evaluate the entry zone of iliac screw fixation to maintain proper entry width and screw length. Computed tomography images of pelvic bones from 90 human cadavers were reconstructed into 3-dimensional models. In each model, a sectional image crossing the posterior superior iliac spine (PSIS) and anterior inferior iliac spine (AIIS) and consecutive sectional images up to 20 mm superiorly and inferiorly from the PSIS with 1-mm intervals aiming the AIIS were obtained. One virtual iliac screw with 10-mm diameter was introduced onto the PSIS at the middle and at the lateral and medial 1/4 points on the prominence of the posterior iliac spine. The entry width of the bony prominence and the corresponding maximal screw length available were evaluated for each entry point. The entry width was smallest on the inferior 20 mm (4.7 ± 3.0 mm) and gradually increased up to the superior 10 mm (19.1 ± 3.9 mm) sectional images. The maximal screw length was smallest on the superior 20 mm (76.7 ± 39.7 mm) and gradually increased down to the inferior 10 mm (112.3 ± 15.1 mm) sectional images. The maximal screw lengths were significantly greatest at the most medial point and smallest at the most lateral point on the superior 20- and 10-mm sectional images and at the PSIS. The iliac screw fixation entry zone to maintain proper screw length and entry width is outlined from 20 mm superiorly to 10 mm inferiorly from the PSIS and is located more medially from the prominence of the posterior iliac spine.

SU-E-J-220: Evaluation of Atlas-Based Auto-Segmentation (ABAS) in Head-And-Neck Adaptive Radiotherapy

Purpose: Evaluate the accuracy of atlas-based auto segmentation of organs at risk (OARs) on both helical CT (HCT) and cone beam CT (CBCT) images in head and neck (HN) cancer adaptive radiotherapy (ART). Methods: Six HN patients treated in the ART process were included in this study. For each patient, three images were selected: pretreatment planning CT (PreTx-HCT), in treatment CT for replanning (InTx-HCT) and a CBCT acquired in the same day of the InTx-HCT. Three clinical procedures of auto segmentation and deformable registration performed in the ART process were evaluated: a) auto segmentation on PreTx-HCT using multi-subject atlases, b) intra-patient propagation of OARs from PreTx-HCT to InTx-HCT using deformable HCT-to-HCT image registration, and c) intra-patient propagation of OARs from PreTx-HCT to CBCT using deformable CBCT-to-HCT image registration. Seven OARs (brainstem, cord, L/R parotid, L/R submandibular gland and mandible) were manually contoured on PreTx-HCT and InTx-HCT for comparison. In addition, manual contours on InTx-CT were copied on the same day CBCT, and a local region rigid body registration was performed accordingly for each individual OAR. For procedures a) and b), auto contours were compared to manual contours, and for c) auto contours were compared to those rigidly transferred contours onmore » CBCT. Dice similarity coefficients (DSC) and mean surface distances of agreement (MSDA) were calculated for evaluation. Results: For procedure a), the mean DSC/MSDA of most OARs are >80%/±2mm. For intra-patient HCT-to-HCT propagation, the Resultimproved to >85%/±1.5mm. Compared to HCT-to-HCT, the mean DSC for HCT-to-CBCT propagation drops ∼2–3% and MSDA increases ∼0.2mm. This Resultindicates that the inferior imaging quality of CBCT seems only degrade auto propagation performance slightly. Conclusion: Auto segmentation and deformable propagation can generate OAR structures on HCT and CBCT images with clinically acceptable accuracy. Therefore, they can be reliably implemented in the clinical HN ART process.« less

Communication spaces

Background and objectiveAnnotations to physical workspaces such as signs and notes are ubiquitous. When densely annotated, work areas become communication spaces. This study aims to characterize the types and purpose of such annotations.MethodsA qualitative observational study was undertaken in two wards and the radiology department of a 440-bed metropolitan teaching hospital. Images were purposefully sampled; 39 were analyzed after excluding inferior images.ResultsAnnotation functions included signaling identity, location, capability, status, availability, and operation. They encoded data, rules or procedural descriptions. Most aggregated into groups that either created a workflow by referencing each other, supported a common workflow without reference to each other, or were heterogeneous, referring to many workflows. Higher-level assemblies of such groupings were also observed.DiscussionAnnotations make visible the gap between work done and the capability of a space to support work. Annotations are repairs of an environment, improving fitness for purpose, fixing inadequacy in design, or meeting emergent needs. Annotations thus record the missing information needed to undertake tasks, typically added post-implemented. Measuring annotation levels post-implementation could help assess the fit of technology to task. Physical and digital spaces could meet broader user needs by formally supporting user customization, ‘programming through annotation’. Augmented reality systems could also directly support annotation, addressing existing information gaps, and enhancing work with context sensitive annotation.ConclusionsCommunication spaces offer a model of how work unfolds. Annotations make visible local adaptation that makes technology fit for purpose post-implementation and suggest an important role for annotatable information systems and digital augmentation of the physical environment.

Retention of 99mTc-DMSA(III) and 99mTc-nanocolloid in different syringes affects imaging quality

(99m)Tc-dimercaptosuccinic acid [DMSA(III)] and colloidal human serum albumin ((99m)Tc-nanocolloid) are widely used radiopharmaceuticals. Recently, in our institution we encountered image quality problems in DMSA scans after changing the brand of syringes we were using, which triggered us to look into the adsorption properties of syringes from different brands for (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid. We also describe a clinical case in which adsorption of (99m)Tc-DMSA(III) caused inferior imaging quality. DMSA and nanocolloid were labeled with (99m)Tc following manufacturer guidelines. After synthesis, syringes with (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid were stored for 15, 30, 60, and 120 min. We evaluated Luer Lock syringes manufactured by different brands such as Artsana, Henke-Sass-Wolf, B. Braun Medical N.V., CODAN Medizinische Geräte GmbH & Co KG, Becton Dickinson and Company, and Terumo Europe. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid was acceptably low for all syringes (<13%), except for two brands with (99m)Tc-DMSA(III) adsorption rates of 36 and 30%, respectively, and for one brand with a (99m)Tc-nanocolloid adsorption rate of 27%. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid reaches critical levels in syringes produced by two brands, potentially causing poor image quality--for example, in DMSA scans using pediatric radiopharmaceutical doses. It is advised to check the compatibility of any radiopharmaceutical with syringes as an integral part of the quality assurance program.

Recognition of Low-Resolution Logos in Vehicle Images Based on Statistical Random Sparse Distribution

Traditional image recognition approaches can achieve high performance only when the images have high resolution and superior quality. A new vehicle logo recognition (VLR) method is proposed to treat low-resolution and poor-quality images captured from urban crossings in intelligent transport system, and the proposed approach is based on statistical random sparse distribution (SRSD) feature and multiscale scanning. The SRSD feature is a novel feature representation strategy that uses the correlation between random sparsely sampled pixel pairs as an image feature and describes the distribution of a grayscale image statistically. Multiscale scanning is a creative classification algorithm that locates and classifies a logo integrally, which alleviates the effect of propagation errors in traditional methods by processing the location and classification separately. Experiments show an overall recognition rate of 97.21% for a set of 3370 vehicle images, which showed that the proposed algorithm outperforms classical VLR methods for low-resolution and inferior quality images and is very suitable for on-site supervision in ITSs.