Vander Lugt Research Articles

Photon counting CT clinical adoption, integration, and workflow.

Photon counting CT was recently introduced into clinical practice [Rajendran K, Petersilka M, Henning A, Shanblatt ER, Schmidt B, Flohr TG, Ferrero A, Baffour F, Diehn FE, Yu L, Rajiah P, Fletcher JG, Leng S, McCollough CH. First Clinical Photon-counting Detector CT System: Technical Evaluation. Radiology 2022;303(1):130-138. doi: https://doi.org/10.1148/radiol.212579 ]. Photon counting detectors (PCD) afford better spatial resolution, radiation dose efficiency, and iodine contrast-to-noise than EID-CT [Leng S, Bruesewitz M, Tao S, Rajendran K, Halaweish AF, Campeau NG, Fletcher JG, McCollough CH. Photon-counting Detector CT: System Design and Clinical Applications of an Emerging Technology. Radiographics 2019;39(3):729-743. doi: https://doi.org/10.1148/rg.2019180115 ); (Leng S, Rajendran K, Gong H, Zhou W, Halaweish AF, Henning A, Kappler S, Baer M, Fletcher JG, McCollough CH. 150-mum Spatial Resolution Using Photon-Counting Detector Computed Tomography Technology: Technical Performance and First Patient Images. Invest Radiol 2018;53(11):655-662. doi: https://doi.org/10.1097/RLI.0000000000000488 )(Booij R, van der Werf NR, Dijkshoorn ML, van der Lugt A, van Straten M. Assessment of Iodine Contrast-To-Noise Ratio in Virtual Monoenergetic Images Reconstructed from Dual-Source Energy-Integrating CT and Photon-Counting CT Data. Diagnostics (Basel) 2022;12(6). doi: https://doi.org/10.3390/diagnostics12061467 ); (Sawall S, Klein L, Amato C, Wehrse E, Dorn S, Maier J, Heinze S, Schlemmer HP, Ziener CH, Uhrig M, Kachelriess M. Iodine contrast-to-noise ratio improvement at unit dose and contrast media volume reduction in whole-body photon-counting CT. Eur J Radiol 2020;126:108909. doi: https://doi.org/10.1016/j.ejrad.2020.108909 ] while also maintaining multienergy CT (MECT) capabilities[Flohr T, Petersilka M, Henning A, Ulzheimer S, Ferda J, Schmidt B. Photon-counting CT review. Phys Med 2020;79:126-136. doi: https://doi.org/10.1016/j.ejmp.2020.10.030 ]. This article will review the clinical adoption of PCD-CT including protocol development, clinical applications, clinical integration and workflow considerations. Protocol development is institution specific and involves collaborative decision-making among radiologists, physicists, and technologists. Key PCD clinical applications include radiation exposure reduction, intravenous contrast volume reduction, and improved lesion conspicuity. Patients who would most benefit from these improvements may preferentially be scanned with PCD CT. With numerous available reconstructions, radiologists should be strategic in the series sent to PACS for interpretation and routinely sending spectral series to PACS can facilitate integration with clinical workflow. The Society of Abdominal Radiology PCD Emerging Technology Commission endorsed this article.

Measurements of morphodynamics of a sheltered beach along the Dutch Wadden Sea

Abstract. A field campaign was carried out at a sheltered sandy beach with the aim of gaining new insights into the driving processes behind sheltered beach morphodynamics. Detailed measurements of the local hydrodynamics, bed-level changes and sediment composition were collected at a man-made beach on the leeside of the barrier island Texel, bordering the Marsdiep basin that is part of the Dutch Wadden Sea. The dataset consists of (1) current, wave and turbidity measurements from a dense cross-shore array and a 3 km alongshore array; (2) sediment composition data from beach surface samples; (3) high-temporal-resolution RTK-GNSS beach profile measurements; (4) a pre-campaign spatially covering topobathy map; and (5) meteorological data. This paper outlines how these measurements were set up and how the data have been processed, stored and can be accessed. The novelty of this dataset lies in the detailed approach to resolve forcing conditions on a sheltered beach, where morphological evolution is governed by a subtle interplay between tidal and wind-driven currents, waves and bed composition, primarily due to the low-energy (near-threshold) forcing. The data are publicly available at 4TU Centre for Research Data at: https://doi.org/10.4121/19c5676c-9cea-49d0-b7a3-7c627e436541 (Van der Lugt et al., 2023).

Neurointerventional Advances in 2022

Neurointerventional Advances in 2022

M1, M2: Time to Bid Adieu!

M1, M2: Time to Bid Adieu!

Gene therapy offers new hope for children with metachromatic leukodystrophy

Metachromatic leukodystrophy (MLD) is a rare, progressive lysosomal storage disease caused by mutations in the gene encoding arylsulfatase A (ARSA), causing disease in the central and peripheral nervous systems. MLD presents in toddlers (late infantile disease) or in children (juvenile disease) with gait disturbances, loss of developmental milestones, and cognitive decline, leading to death in childhood. It is frequently not diagnosed until the later symptomatic phase when it is too late to intervene. Haematopoietic stem-cell transplantation (HSCT) from allogeneic donors has been used with mixed results. Although HSCT can slow progression of disease in the central nervous system, it does not prevent progression in the peripheral nervous system. HSCT is also associated with risks of graft-versus-host disease and treatment-related toxicity. 1 Boucher AA Miller W Shanley R et al. Long-term outcomes after allogeneic hematopoietic stem cell transplantation for metachromatic leukodystrophy: the largest single-institution cohort report. Orphanet J Rare Dis. 2015; 10: 94 Crossref PubMed Scopus (66) Google Scholar , 2 Wolf NI Breur M Plug B et al. Metachromatic leukodystrophy and transplantation: remyelination, no cross-correction. Ann Clin Transl Neurol. 2020; 7: 169-180 Crossref PubMed Scopus (11) Google Scholar , 3 Beschle J Döring M Kehrer C et al. Early clinical course after hematopoietic stem cell transplantation in children with juvenile metachromatic leukodystrophy. Mol Cell Pediatr. 2020; 7: 12 Crossref PubMed Google Scholar , 4 Vander Lugt MT Chen X Escolar ML et al. Reduced-intensity single-unit unrelated cord blood transplant with optional immune boost for nonmalignant disorders. Blood Adv. 2020; 4: 3041-3052 Crossref PubMed Scopus (3) Google Scholar Additionally, small trials of intrathecal gene therapy in mice or humans did not result in improvement in symptoms of clinical disease. 5 Miyake N Miyake K Sakai A Yamamoto M Suzuki H Shimada T Treatment of adult metachromatic leukodystrophy model mice using intrathecal administration of type 9 AAV vector encoding arylsulfatase A. Sci Rep. 2021; 1120513 Crossref PubMed Scopus (1) Google Scholar Thus, new therapeutic approaches are desperately needed. Lentiviral haematopoietic stem-cell gene therapy for early-onset metachromatic leukodystrophy: long-term results from a non-randomised, open-label, phase 1/2 trial and expanded accessTreatment with arsa-cel resulted in sustained, clinically relevant benefits in children with early-onset MLD by preserving cognitive function and motor development in most patients, and slowing demyelination and brain atrophy. Full-Text PDF Open Access

Holographic photonic neuron

Abstract The promise of artificial intelligence (AI) to process complex datasets has brought about innovative computing paradigms. While recent developments in quantum-photonic computing have reached significant feats, mimicking our brain’s ability to recognize images are poorly integrated in these ventures. Here, I incorporate orbital angular momentum (OAM) states in a classical Vander Lugt optical correlator to create the holographic photonic neuron (HoloPheuron). The HoloPheuron can memorize an array of matched filters in a single phase-hologram, which is derived by linking OAM states with elements in the array. Successful correlation is independent of intensity and yields photons with OAM states of lℏ, which can be used as a transmission protocol or qudits for quantum computing. The unique OAM identifier establishes the HoloPheuron as a fundamental AI device for pattern recognition that can be scaled and integrated with other computing platforms to build-up a robust neuromorphic quantum-photonic processor.

Driver Drowsiness Detection Based on Drivers’ Physical Behaviours: A Systematic Literature Review

One of the most common causes of traffic accidents is human error. One such factor involves the drowsy drivers that do not focus on the road before them. Driver drowsiness often occurs due to fatigue in long distances or long durations of driving. The signs of a drowsy driver may be detected based on one out of three types of tests; i.e., performance test, physiological test, and behavioural test. Since the physiological and performance tests are quite difficult and expensive to implement, the behavioural test is a good choice to use for detecting early drowsiness. Behaviour-based driver drowsiness detection has been one of the hot research topics in recent years and is still increasingly developing. There are many approaches for behavioural driver drowsiness detection, such as Neural Networks, Multi Layer Perceptron, Support Vector Machine, Vander Lugt Correlator, Haar Cascade, and Eye Aspect Ratio. Therefore, this study aims to conduct a systematic literature review to elaborate on the development and research trends regarding driver drowsiness detection. We hope to provide a good overview of the current state of research and offer the research potential in the future.

Potential of Plasmatic Biomarkers to Predict Acute Gvhd Severity: A Validation Study in a Prospective Cohort of 177 Patients

Background: Several biological markers have been reported to predict response to treatment and mortality in patients with acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplant. aGVHD is a major concern since it significantly impacts outcome, especially in patients with steroid refractory aGVHD, leading to a high mortality rate (>50%). The present study was designed to validate a prognostic score based on 6 plasmatic biomarkers: Elafin, IL2Ra, TNFRI, HGF, IL8, and REG3a (Levine et al. Blood 2012).Methods: A prospective study was conducted between 2013 and 2017 in our institution in patients presenting with aGVHD after transplantation for hematological disease. One blood sample was taken at diagnosis of aGVHD and clinical data were prospectively collected. No response at day 30 after aGVHD onset was defined as non-complete response or requirement of a second line therapy. Association of biomarkers with day-30 response and overall survival was analyzed by logistic and Cox models, respectively. Discriminative ability of the models was quantified by the c index. The biomarkers were measured by a multiplex Luminex based assay (R&D systems) except one which was measured by ELISA (REG3a).Patient characteristics: Median age at inclusion was 45 years, 63 (36 %) patients were women; hematological disease prior transplant was acute myeloid leukemia or myelodysplastic syndrome in 36 (20%), lymphoma in 31 (18%), acute lymphoid leukemia in 32 (18%) and myeloproliferative neoplasms in 24 (14%) patients. A reduced intensity conditioning regimen was used in 117 (66%) and the donor was an HLA-matched sibling donor in 51 (29%) patients, matched unrelated in 82 (46%) and HLA-mismatched in 44 (25%). Sources of stem cells were G-CSF mobilized peripheral blood stem cells in 138 (78%), bone marrow in 23 (13%) and unrelated cord blood in 16 (9%) patients. aGVHD occurred at a median of 22 days after transplant (range 6 - 77) and was graded I, II and III at time of aGVHD diagnosis for 12%, 57% and 31% of patients respectively. At inclusion, aGVHD involved skin (n=143), gut (n=138) and/or liver (n=29). At day 30 after treatment initiation, 123 (69%) patients had a complete response. The follow-up was greater than 6 months at time of analysis for all living patients. Forty patients were dead 180 days after the aGVHD episode.Results: Plasmatic biomarkers were measured at time of corticosteroids initiation at aGVHD onset in 177 patients. Predictive potential was assessed on response at day 30 and mortality at 6 months. The score was significantly associated with day-30 response and 6-month mortality, as already reported. In a multivariable analysis, after adjustment for aGVHD grade at initiation of treatment, age, donor type (related or unrelated), source of stem cells, albumin level and fever, the score was still predictive for day-30 response and 6-month mortality, along with aGVHD grade (table 1). None of the other parameters were associated with day-30 response while age and donor type were associated with 6-months mortality. The same multivariate analysis was further conducted with ST2, another strong prognostic biomarker previously described (Vander Lugt et al NEJM 2013). After adjustment for the other variables, ST2 was associated with 6-month mortality only (table 1).Finally, we used the c-index to estimate the discriminative ability of the score alone, ST2 alone or the combination of score and ST2. The score had the highest value to discriminate response at day-30 (c-index=0.68) as compared to ST2 (c-index=0.60) and the combination score+ST2 (c-index=0.66). The combination score+ST2 had the highest value to predict 6-month mortality (c-index=0.68) as compared to the score (c-index=0.64) and ST2 (c-index=0.59) alone.Conclusion: The present study shows the potential of a score based on 6 biomarkers (Elafin, IL2Ra, TNFRI, HGF, IL8, and REG3a) and of ST2, to predict severity of aGVHD, after adjustment for other variables. However, when tested for discriminative value by the c-index, our results support the need for improved biomarker studies and prospective trials designed to re-enforce immunosuppressive therapy in patients with unfavorable biomarkers, while patients with favorable biomarkers could possibly benefit from less intensive aGVHD therapy. This study corroborates the ability of a score based on 6 biomarkers to predict severity of aGVHD in an independent cohort of patients. [Display omitted] DisclosuresPeffault De Latour:Alexion Pharmaceuticals, Inc.: Consultancy, Honoraria, Research Funding; Amgen: Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding. Socié:Alexion Pharmaceuticals, Inc.: Consultancy.

Analysis focused image formation in double exposure speckle photography

This paper presents the theoretical and experimental results of the analysis of the formation of the focused image in a double-exposure speckle photography. Theoretical analysis of the formation of the focused image in double-exposure speckle photography was carried out using the Vander Lugt method. It is shown that as a result of the summation of speckle structures displaced in the space of the photographic plates, moiré fringes are formed in double-exposure speckle photography. Experimental results confirming theoretical studies are presented.

Structured light based optical pattern recognition:Principle and technical progress

<p indent=0mm>Optical image recognition technology has attracted considerable attention due to its advantages, such as extensive information processing capacity, high-speed calculation, and advanced parallel processing. This technology also has various applications in security systems, remote sensing imaging, biomedical technology, and military scenarios. With the development of structured optical engineering technology, optical image recognition has gained new vitality in recent years. This paper describes two major optical image recognition correlators, the Vander Lugt Correlator and Joint Transform Correlator. We describe the progress of research on optical pattern recognition in the framework of linear optics, nonlinear optics, and quantum correlation. Our study also emphasizes how structured light engineering technologies can be incorporated into all-optical pattern recognition systems to accelerate technological developments.

Pre-Transplantation ST2 Levels and Non-Relapse Mortality after Myeloablative Allogeneic Hematopoietic Cell Transplantation

Introduction: Suppression of tumorigenicity 2 (ST2) is a prognostic plasma marker of non-relapse mortality (NRM) after allogeneic hematopoietic cell transplantation (allo-HCT) when measured at day +14 [Vander Lugt MT et al., N Engl J Med, 2013] and at day +7 in combination with regenerating islet-derived 3α (REG3α) [Hartwell MJ et al., JCI Insight, 2017]. We hypothesized that also pre-transplantation ST2 levels would be associated with NRM in the first 6 months after allo-HCT. Methods: We studied 112 adult patients who underwent allo-HCT with myeloablative conditioning at Rigshospitalet between July 2015 and August 2018 (Table 1). ST2 levels were measured by enzyme-linked immunosorbent assays using stored EDTA plasma samples obtained at the patients' scheduled pre-transplantation visit around day -23 (±11 days) and post-transplantation at days +7 and +14 (±3 days, n = 76 and 66). Univariable linear models and Spearman's ρ were used to evaluate associations and correlations between pre-transplantation ST2 levels and patient characteristics and other prognostic markers, respectively. Cause-specific Cox regression models were used to estimate hazard ratios (HR) with 95% confidence intervals (CI) for NRM in the first 6 months after allo-HCT (relapse as competing risk) and grade II-IV acute graft-versus-host disease (GvHD) in the first 100 days after allo-HCT (NRM and relapse as competing risks) according to pre-transplantation ST2 levels. Gray's test was used to test differences in the cumulative incidence of NRM in the first 6 months after allo-HCT according to quartiles of pre-transplantation ST2 levels. Results: The median pre-transplantation plasma ST2 level was 19.9 ng/mL (inter-quartile range: 14.6-25.7 ng/mL, Figure Panel A); levels were higher in males (β = 8.7 ng/mL, p &amp;lt; 0.01), but did not differ by age (p = 0.81) or by being transplanted for acute leukemia (p = 0.89). ST2 was correlated with C-reactive protein (ρ = 0.24, p = 0.01), the endothelial activation and stress index (EASIX, calculated as creatinine x lactate dehydrogenase/thrombocytes, ρ = 0.27, p &amp;lt; 0.01) and ferritin (ρ = 0.28, p &amp;lt; 0.01). Longitudinally, pre-transplantation ST2 levels were strongly correlated with ST2 levels on day +7 (ρ = 0.57, p &amp;lt; 0.01) and day +14 (ρ = 0.48, p &amp;lt; 0.01). The cumulative incidence of NRM at 6 months was 11% (n = 12); causes of death were organ failure (75%), acute graft-versus-host disease (GvHD, 17%) and infection (8%). Higher pre-transplantation ST2 levels were associated with increased hazard of NRM in the first 6 months after allo-HCT (HR 1.73 per 10 ng/mL increase, 95% CI: 1.28-2.33, p &amp;lt; 0.01, area under the receiver operating characteristics curve = 0.61). Despite a significantly higher NRM in patients with pre-transplantation ST2 levels in the highest quartile (cumulative incidence at 6 months: 21% vs. 7% in patients with levels in the three lower quartiles, p = 0.03), there was no overall significant difference in NRM according to quartiles of pre-transplantation ST2 levels (p = 0.15, Figure Panel B). No significant association was found between pre-transplantation ST2 levels and grade II-IV acute GvHD (HR 0.88, 95% CI: 0.61-1.26, p = 0.48). Conclusion: Pre-transplantation ST2 levels were associated with increased NRM in the first 6 months after myeloablative allo-HCT, mainly driven by higher NRM in patients with pre-transplantation ST2 levels in the highest quartile. Larger studies are warranted to validate pre-transplantation ST2 levels as a prognostic marker of NRM after allo-HCT, which potentially could be used to support the choice of conditioning intensity. Disclosures No relevant conflicts of interest to declare.

Prehospital Triage of Patients with Suspected Stroke (PRESTO): A Prospective In-Field Validation of Eight Prehospital Stroke Scales to Detect Intracranial Large Vessel Occlusion

Background: Due to the time-sensitive effect of endovascular treatment (EVT), rapid prehospital identification of large vessel occlusion (LVO) in suspected stroke patients is essential to optimize outcome. Inter-hospital transfers are an important cause of delay of EVT. Prehospital stroke scales have been proposed to select patients with LVO for direct transport to an endovascular-capable intervention centre. We aimed to prospectively validate eight prehospital stroke scales in the field. Methods: In a multi-centre prospective observational cohort study, we included suspected stroke patients transported by ambulance in the Southwest Netherlands. Paramedics assessed items from eight prehospital stroke scales: Rapid Arterial oCclusion Evaluation (RACE), Los Angeles Motor Scale (LAMS), Cincinnati Stroke Triage Assessment Tool (C-STAT), Gaze-Face-Arm-Speech-Time (G-FAST), Prehospital Acute Stroke Severity (PASS), Cincinnati Prehospital Stroke Scale (CPSS), Conveniently-Grasped Field Assessment Stroke Triage (CG-FAST), and the FAST PLUS Test. Patients that presented beyond six hours from symptom onset were excluded. Primary outcome was the clinical diagnosis of ischaemic stroke with a proximal intracranial LVO in the anterior circulation (aLVO) on CT-angiography. Prehospital stroke scale performance was expressed as the area under the receiver operating characteristic curve (AUC) and was compared with National Institute of Health Stroke Scale (NIHSS) scores assessed by physicians at the emergency department. Findings: We included 1039 patients, of which 121 patients (12%) were diagnosed with aLVO. AUCs for the prehospital stroke scales ranged from 0·69 (FAST PLUS) to 0·82 (RACE). The performance of RACE was not significantly different from G-FAST (AUC=0·80, p=0·14) and CG-FAST (AUC=0·80, p=0·09), but was significantly different from the other scales (p-values<0·05). The NIHSS performed somewhat better (AUC 0·86, p-values<0·05). Interpretation: Prehospital stroke scales detect aLVO with good accuracy and approach the performance of the physician-assessed NIHSS. RACE is the best performing prehospital stroke scale, but does not differ significantly from G-FAST and CG-FAST. Trial Registration: This study was registered at the Netherlands Trial Register (www.trialregister.nl), NL7387 Funding: BeterKeten collaboration and Theia Foundation (Zilveren Kruis) Declaration of Interests: Diederik Dippel and Aad van der Lugt report funding from the Dutch Heart Foundation, Brain Foundation Netherlands, The Netherlands Organisation for Health Research and Development, Health Holland Top Sector Life Sciences & Health, and unrestricted grants from Penumbra Inc., Stryker, Stryker European Operations BV, Medtronic, Thrombolytic Science, LLC and Cerenovus for research, all paid to institution. Pieter Jan van Doormaal reports funding from Stryker, paid to institution and an unrestricted fee from Bayer. All other authors declare no conflict of interest. Ethics Approval Statement: This study was conducted in accordance with the Dutch Agreement on Medical Treatment Act and the European General Data Protection Regulation. The Institutional Review Board of the Erasmus MC University Medical Centre has reviewed the study protocol and confirmed that the Dutch Medical Research Involving Human Subjects Act is not applicable. Because our study met the exceptions of informed consent regulations, the need for informed consent was waived. Patients or their relatives were informed about the study and could withdraw from the study through an opt-out system.

Optical correlator based algorithm for driver drowsiness detection

The human eye and its characteristics (texture, gaze, and movement) have shown to be reliable in expressing human emotional states. A non-invasive eye tracking and state (open/close) estimation system is, consequently, fundamental for developing human-machine interaction systems, hands-off process control, and fatigue detection.In the current work, a novel and fast method based on an optical correlator is proposed for eye detection first, followed by eye state estimation. The second aim of this work was to investigate the simulated optical correlator on a real world driving videos for driver drowsiness detection. For the first time, a numerical simulation of the Vander Lugt Correlator (VLC) was used for automatically detecting the eye center. Further, correlation filters tailored to all the eye states were proposed and their design, to recognize eyes in cluttering and noisy environments, was investigated. Besides, the correlation peak amplitude returned by the VLC based algorithm was investigated to detect the driver drowsiness.Results reported on four international databases reveal that the proposed method improves over the recently published methods in eye tracking. Evaluations of the simulated VLC on real world driving videos from the SHRP2 database demonstrate its good performance on the driver's eye tracking and closure detection.

Prevalence and the Risk Factors for Asymptomatic Carotid Artery Stenosis Among Type II Diabetes Mellitus Patients

Prevalence and the Risk Factors for Asymptomatic Carotid Artery Stenosis Among Type II Diabetes Mellitus Patients

Low-Dose Computed Tomography With Two- and Three-Dimensional Postprocessing as an Alternative to Plain Radiography for Intrathecal Catheter Visualization: A Phantom Pilot Study

ObjectivesIn intrathecal drug delivery, visualization of the device has been performed with plain radiography. However, the visibility of the related structures can be problematic. In troubleshooting, after the contrast material injection via the catheter access port, a computed tomography (CT) scan has been used. In troubleshooting, we also used a non‐contrast CT scan with 2D and 3D reconstructions. With the current phantom study, we aimed to obtain high‐resolution imaging of a poor opaque catheter with the use of a low‐dose single‐energy 2D and 3D CT scan with limited radiation exposure as a substitute for plain radiography.Materials and MethodsThe catheter was placed into a fatty substance and mounted on an anthropomorphic abdomen phantom followed by CT with varying kVp settings and with added tin beam filtering. Dose levels corrected based on the spinal catheter tip on T8 would result in a calculated effective dose in the range of the mSv's calculated for the plain x‐ray examination.ResultsUltimately, Sn100 kVp has the best trade‐off between visibility, artifacts, and noise for a fixed dose. Although 3D VRT imaging was challenging at this low dose level, we could make a full evaluation possible with complementary 2D projections.ConclusionsWe could correctly identify the catheter and related structures, which supports the investigation of this in vivo and side‐by‐side evaluation with plain radiography. If found superior, then this technique may be able to replace plain radiography, while providing better visualization and acceptable radiation exposure.Conflict of InterestDr. Delhaas reports personal fees from Medtronic Inc., as a previous consultant, outside the submitted work; Prof. van der Lugt reports grants from GE Healthcare, Siemens, Stryker, Medtronic, and Penumbra outside the submitted work.

Hybrid Approach for Face Recognition from a Single Sample per Person by Combining VLC and GOM

Abstract This paper proposes a new face recognition system based on combining two feature extraction techniques: the Vander Lugt correlator (VLC) and Gabor ordinal measures (GOM). The proposed system relies on the execution speed of VLC and the robustness of GOM. In this system, we applied the Tan and Triggs and retina modeling enhancement techniques, which are well suited for VLC and GOM, respectively. We evaluated our system on the standard FERET probe data sets and on extended YaleB database. The obtained results exhibited better face recognition rates in a shorter execution time compared to the GOM technique.

Structured-Pump-Enabled Quantum Pattern Recognition.

We report a new scheme of ghost imaging by using a spatially structured pump in the Fourier domain of spontaneous parametric down-conversion for quantum-correlation-based pattern recognition. We exploit the mathematical feature of Laguerre-Gaussian mode's Fourier transform to describe the pump-modulated formation of a ghost image. Of particular interest is the experimental demonstration of a quantum equivalence of a Vander Lugt filter, based on which the nonlocal spiral phase contrast for vortex mapping and quantum-correlation-based human face recognition are implemented successfully. The photons used for probing a test object, scanning the database, and producing a correlation signal can belong to three different light beams, which suggests some security applications where low-light-level illumination and covert operation are desired.

HOLOGRAPHIC ASSOCIATIVE MEMORY PROBLEM WITHIN CORRELATION-OPTICAL APPROACH

Проблема голографічної асоціативної пам’яті обговорюється в рамках кореляційно-оптичного підходу. Аналіз моделей безопорної голограми та нелінійно зареєстрованих позаосевих голограм, зчитуваних в асоціативному режимі, показує широкий спектр корисних властивостей таких голограм не лише для відновлення відсутньої частини збереженого масиву даних, а й для детектування малих змін (помилок) у записаній картині, для відновлення повного масиву даних з корекцією помилок за неповною версією масиву, а також для здійснення високоефективного гетероасоціативного відновлення на базі неінтерференційного механізму зв’язку парціальних сигналів. Показано, що візуально оцінювана якість відновленого асоціативного відгуку може наближатись до якості зображення, що досягається у звичайній позаосевій голографії.

Abstract LB-150: Neoantigens that fail to elicit measurable T cell responses following peptide immunization can control tumor growth when delivered using a Listeria-based immunotherapy platform

Abstract Introduction: Recent advances in the field of cancer immunotherapy have identified CD8+ T cell responses against tumor-specific neoantigens as a key driver of tumor regression and prolonged survival. ADXS-NEO is a personalized Listeria monocytogenes (Lm)-based immunotherapy designed to generate immune responses against mutation-derived tumor-specific neoantigens. Advaxis' Lm-based immunotherapies consist of live highly-attenuated bacterial vectors that are bioengineered to secrete a fusion protein consisting of a truncated non-hemolytic fragment of listeriolysin O, which has adjuvant properties, and tumor-specific neoantigens that harbor nonsynonymous point mutations (NSMs). The objective of this study is to demonstrate the feasibility of using the ADXS-NEO platform to target tumor-specific point mutations to generate neoantigen-specific T cells and control tumor growth. Results: Whole-exome sequencing of the MC38 mouse tumor cell line identified 2870 unique NSMs. Among these, the IC50 of 138 NSMs were predicted to be less than 500 nM by the netMHCcons algorithm. We evaluated the immunogenicity of 37 NSMs, and found that 12 immunogenic NSMs elicited a CD8+ T cell response following peptide immunization. Moreover, we identified 10 additional immunogenic NSMs in MC38-bearing mice treated with a check point inhibitor. Altogether, we identified 22 immunogenic and 23 non-immunogenic NSMs. Two ADXS-NEO vectors were constructed, Lm-19 &amp; Lm-20, targeting 19 non-immunogenic and 20 immunogenic NSMs respectively. The ability of Lm-19 and Lm-20 to control MC38 tumor growth was evaluated in C57BL/6J mice. We found that both Lm-19 &amp; Lm-20 led to an accumulation of neoantigen-specific CD8+ TILs and significantly slowed tumor growth. Moreover, both Lm-19 and Lm-20 decreased the frequency and absolute number of intratumoral Tregs, TAMs, and MDSCs and increased the frequency and absolute number of effector CD8+ T cells. Interestingly, expression of PD-L1 was decreased in TAMs and MDSCs and the frequency and total number of granzyme A+ CD8+ effector T cells was increased. Furthermore, the proportion of phenotypically exhausted PD-1hiLAG3+ TILs was decreased. Together, these data suggest the tumor microenvironment in mice receiving Lm-19 and Lm-20 becomes more cytotoxic and less suppressive. Conclusion: ADXS-NEO is a potent immunotherapy capable of driving immune responses against tumor-specific mutations and leading to tumor control. The effectiveness of the Lm platform is demonstrated by the generation of neoantigen-specific T cells to peptide sequences that were identified as “non-immunogenic” using a conventional peptide-adjuvant immunization. This study is a clear demonstration that T cell mediated anti-tumor responses can be generated by targeting tumor-derived NSMs with the ADXS-NEO Listeria monocytogenes vector. Citation Format: Brandon Coder, Hyewon Phee, Cristina Mottershead, Dipti Kelkar, Elena Filippova, Xiaoming Ju, Bryan Vander Lugt, Olga Pryshchep, Justin Lesch, Xian Liu, Jason DeVoss, Keegan Cooke, Claret Liu, Jinghui Zhan, Petia Mitchell, Kim Ramos, Daniel O. Villarreal, Jim Johnston, Robert Petit, Michael Princiotta. Neoantigens that fail to elicit measurable T cell responses following peptide immunization can control tumor growth when delivered using a Listeria-based immunotherapy platform [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-150.

Brain tumor segmentation with Vander Lugt correlator based active contour

Background and objectiveThe manual segmentation of brain tumors from medical images is an error-prone, sensitive, and time-absorbing process. This paper presents an automatic and fast method of brain tumor segmentation. MethodsIn the proposed method, a numerical simulation of the optical Vander Lugt correlator is used for automatically detecting the abnormal tissue region. The tumor filter, used in the simulated optical correlation, is tailored to all the brain tumor types and especially to the Glioblastoma, which considered to be the most aggressive cancer. The simulated optical correlation, computed between Magnetic Resonance Images (MRI) and this filter, estimates precisely and automatically the initial contour inside the tumorous tissue. Further, in the segmentation part, the detected initial contour is used to define an active contour model and presenting the problematic as an energy minimization problem. As a result, this initial contour assists the algorithm to evolve an active contour model towards the exact tumor boundaries. Equally important, for a comparison purposes, we considered different active contour models and investigated their impact on the performance of the segmentation task. Several images from BRATS database with tumors anywhere in images and having different sizes, contrast, and shape, are used to test the proposed system. Furthermore, several performance metrics are computed to present an aggregate overview of the proposed method advantages. ResultsThe proposed method achieves a high accuracy in detecting the tumorous tissue by a parameter returned by the simulated optical correlation. In addition, the proposed method yields better performance compared to the active contour based methods with the averages of Sensitivity=0.9733, Dice coefficient = 0.9663, Hausdroff distance = 2.6540, Specificity = 0.9994, and faster with a computational time average of 0.4119 s per image. ConclusionsResults reported on BRATS database reveal that our proposed system improves over the recently published state-of-the-art methods in brain tumor detection and segmentation.