Deep Learning in Medical Image Analysis

The accelerating power of deep learning in diagnosing diseases will empower physicians and speed up decision making in clinical environments. Applications of modern medical instruments and digitalization of medical care have generated enormous amounts of medical images in recent years. In this big data arena, new deep learning methods and computational models for efficient data processing, analysis, and modeling of the generated data are crucially important for clinical applications and understanding the underlying biological process. This book presents and highlights novel algorithms, architectures, techniques, and applications of deep learning for medical image analysis

Department of Radiology-Annual Executive Summary Report-July 1, 1989 to June 30, 1990

Department of Radiology Chairman, Vice Chairman 1 Divisions and Directors 1 Committees and Chairmen 1 Department Full Time Faculty 2 Faculty with Secondary Appointments 3 Adjunct Faculty 3 Radiology Residents and Fellows 4 Department Organization Charts 5 State of the Department 7 Teaching Programs Introduction 17 A. Teaching Programs for Medical Students 17 B. Residency Program 18 C. Training Programs for Fellows 19 D. Continuing Medical Education (CME) Programs . 20 Radiology Grand Rounds 21 Radiology Research Conferences 23 Publications Publications 25 Abstracts 34 Presentations Scientific Presentations 43 Exhibits and Poster Presentations 66 Honors, Editorial Activities, Service for National or Regional Radiology Organizations 69 Appendix A: Funded Researc

Sviluppo di un tomografo multi-energy per lo studio pre-clinico di nuove metodiche diagnostiche finalizzate al riconoscimento precoce della patologia tumorale

A new multi-energy CT for small animals is being developed at the Physics Department of the University of Bologna, Italy. The system makes use of a set of quasi-monochromatic X-ray beams, with energy tunable in a range from 26 KeV to 72 KeV. These beams are produced by Bragg diffraction on a Highly Oriented Pyrolytic Graphite crystal. With quasi-monochromatic sources it is possible to perform multi-energy investigation in a more effective way, as compared with conventional X-ray tubes. Multi-energy techniques allow extracting physical information from the materials, such as effective atomic number, mass-thickness, density, that can be used to distinguish and quantitatively characterize the irradiated tissues. The aim of the system is the investigation and the development of new pre-clinic methods for the early detection of the tumors in small animals. An innovative technique, the Triple-Energy Radiography with Contrast Medium (TER), has been successfully implemented on our system. TER consist in combining a set of three quasi-monochromatic images of an object, in order to obtain a corresponding set of three single-tissue images, which are the mass-thickness map of three reference materials. TER can be applied to the quantitative mass-thickness-map reconstruction of a contrast medium, because it is able to remove completely the signal due to other tissues (i.e. the structural background noise). The technique is very sensitive to the contrast medium and is insensitive to the superposition of different materials. The method is a good candidate to the early detection of the tumor angiogenesis in mice. In this work we describe the tomographic system, with a particular focus on the quasi-monochromatic source. Moreover the TER method is presented with some preliminary results about small animal imaging

Evaluation of the effect of breast implants on the accuracy of the CT attenuation Correction (CTAC) map for SPECT/CT myocardial perfusion imaging: a phantom study

Background: Myocardial perfusion imaging (MPI) using single photon emission computedtomography (SPECT) imaging can assess myocardial viability and perfusion. However,overlying thoracic structures, such as ribs or breast tissue lead to gamma ray attenuation. Thisattenuation does not occur equally for all body regions. Photons emitted from deeper structureswill undergo more attenuation than superficial structures, causing artefacts within the imagethat can mimic pathology - such as ischaemia. Such artefacts can be removed or minimised byusing attenuation correction (AC) maps generated using computed tomography (CT). Breastimplants that have density higher than normal breast tissue, could affect the accuracy of the CTnumbers used for AC.Methods: Imaging protocols were compared with and without three sizes of breast implant, ina phantom study. The first experiment used a diagnostic CT scanner to design the method. Thesecond experiment was carried out in a clinical centre using the CT components of a SPECT/CTscanner to assess the impact of three different breast implants on CT number accuracy whenthe CTAC is applied in SPECT/CT MPI. The last experiment used a clinical SPECT/CTscanner and 99mTC as a radiotracer to mimic the clinical MPI scan.Results: The first and second experiments found that large breast implants led to a greaterdifference in CT HU and CT numbers compared to baseline, than the small or medium implants,but the differences were within the tolerance range (±5HUs). This suggested that even largebreast implants did not impact in a clinically significant way on the accuracy of CT HUs andCT numbers. However, the third experiment found that large breast implants resulted in a moresignificant difference in corrected counts and thus more overcorrection than small or mediumbreast implants.Conclusion: The study illustrates that large breast implants resulted in a greater differences inCT HUs, CT number and corrected counts than small or medium implants. Increasing the tubecurrent (mA) improves the CT HU accuracy without significant impact, apart from an increasein the radiation dose to the patient

Life Sciences Program Tasks and Bibliography for FY 1996

This document includes information on all peer reviewed projects funded by the Office of Life and Microgravity Sciences and Applications, Life Sciences Division during fiscal year 1996. This document will be published annually and made available to scientists in the space life sciences field both as a hard copy and as an interactive Internet web page

Assessing the impact of motion on treatment planning during stereotactic body radiotherapy of lung cancer

Cancer is a leading cause of death in Australia and approximately 52% of cancer patients will require radiotherapy at some stage in their treatment. In recent years, stereotactic radiotherapy has emerged as an increasingly common treatment modality for small lesions in various sites of the human body.  To facilitate the investigation into the effects of imaging small mobile lesions, a see-saw 4D-CT phantom was developed. This phantom was used to investigate phase-binning artifacts that can be present when assigning an insufficient number of phases to 4D-CT data. The interplay between a lesion’s size and its amplitude, and the effects this relationship has on 4D-CT data was also investigated. An upgrade to a commercially available respiratory motion phantom was also pursued in order to replicate patient motion recorded with the Varian RPM system. Monte Carlo methods were used to determine the impact of motion on PET data by incorporating a computational moving phantom (XCAT) with a full Monte Carlo model of a commercially available PET scanner. To assess the impact of motion on treatment planning and dose calculation, two treatment planning scenarios were simulated using Monte Carlo. The traditional method of calculating dose on an average intensity projection from 4D-CT was compared to 4D dose calculation, in which tumour motion data from 4D-CT is explicitly incorporated into the treatment plan. Monte Carlo methods are also employed to evaluate the degree of underdosage at the periphery of lung lesions arising from electronic disequilibrium associated with density changes.  It was found that small lesions typically seen in SBRT of lung cancer require extra care when considering treatment planning, motion mitigation, and treatment delivery. The upgraded QUASAR phantom allows for patient specific verification of SBRT/SABR treatment plans to be conducted and was found to replicate patient motion accurately. Respiratory analysis software presented in this work enables detailed statistics of a patient’s respiratory characteristics to be evaluated. The number of phase-bins required to mitigate banding artifacts in 4D-CT projections is quantified in a simple equation for sinusoidal motion. It was also found that for lesion with diameters greater than 2.0 cm and amplitudes less than 4.0 cm, ten phase-bins are adequate to negate all banding artifacts in projection images.  Experimental and Monte Carlo simulations of PET and 4D-PET revealed that motion greater than 1.0 cm resulted in a reduction in apparent activity that increased with motion amplitude. A Dose Reduction Factor (DRF) metric was developed using Monte Carlo simulation which is defined as the ratio of the average dose to the periphery of the lesion to the dose in the central portion. The mean DRF was found to be 0.97 and 0.92 for 6 MV and 15 MV photon beams respectively, for lesion sizes ranging from 10 – 50 mm. The dynamic scenario was simulated with 4D dose calculation methods of registering and adding the dose distributions in each phase-bin from 4D-CT. The dose-volume distributions compared well with 3D (AIP) methods if multiple beams were used and the amplitude of motion was less than 3.0 cm.  

An assessment of cortical function in expert and novice surgeons

Imperial Users onl

Doctor of Philosophy

dissertationIn Chapter 1, an introduction to basic principles or MRI is given, including the physical principles, basic pulse sequences, and basic hardware. Following the introduction, five different published and yet unpublished papers for improving the utility of MRI are shown. Chapter 2 discusses a small rodent imaging system that was developed for a clinical 3 T MRI scanner. The system integrated specialized radiofrequency (RF) coils with an insertable gradient, enabling 100 'm isotropic resolution imaging of the guinea pig cochlea in vivo, doubling the body gradient strength, slew rate, and contrast-to-noise ratio, and resulting in twice the signal-to-noise (SNR) when compared to the smallest conforming birdcage. Chapter 3 discusses a system using BOLD MRI to measure T2* and invasive fiberoptic probes to measure renal oxygenation (pO2). The significance of this experiment is that it demonstrated previously unknown physiological effects on pO2, such as breath-holds that had an immediate (<1 sec) pO2 decrease (~6 mmHg), and bladder pressure that had pO2 increases (~6 mmHg). Chapter 4 determined the correlation between indicators of renal health and renal fat content. The R2 correlation between renal fat content and eGFR, serum cystatin C, urine protein, and BMI was less than 0.03, with a sample size of ~100 subjects, suggesting that renal fat content will not be a useful indicator of renal health. Chapter 5 is a hardware and pulse sequence technique for acquiring multinuclear 1H and 23Na data within the same pulse sequence. Our system demonstrated a very simple, inexpensive solution to SMI and acquired both nuclei on two 23Na channels using external modifications, and is the first demonstration of radially acquired SMI. Chapter 6 discusses a composite sodium and proton breast array that demonstrated a 2-5x improvement in sodium SNR and similar proton SNR when compared to a large coil with a linear sodium and linear proton channel. This coil is unique in that sodium receive loops are typically built with at least twice the diameter so that they do not have similar SNR increases. The final chapter summarizes the previous chapters

Bronx Community College Catalog 2016-2016

Course catalog for Bronx Community College for 2015-16