Image Features for Tuberculosis Classification in Digital Chest Radiographs

Tuberculosis (TB) is a respiratory disease which affects millions of people each year, accounting for the tenth leading cause of death worldwide, and is especially prevalent in underdeveloped regions where access to adequate medical care may be limited. Analysis of digital chest radiographs (CXRs) is a common and inexpensive method for the diagnosis of TB; however, a trained radiologist is required to interpret the results, and is subject to human error. Computer-Aided Detection (CAD) systems are a promising machine-learning based solution to automate the diagnosis of TB from CXR images. As the dimensionality of a high-resolution CXR image is very large, image features are used to describe the CXR image in a lower dimension while preserving the elements in the CXR necessary for the detection of TB. In this thesis, I present a set of image features using Pyramid Histogram of Oriented Gradients, Local Binary Patterns, and Principal Component Analysis which provides high classifier performance on two publicly available CXR datasets, and compare my results to current state-of-the-art research

Accuracy of pelvis repositioning in individuals with and without low back pain

Proprioception allows the body to maintain proper orientation during static and dynamic activities. In the upper and lower extremities, research has demonstrated a loss of some aspects of proprioception and improvement in proprioception with retraining. It was hypothesized that persons with low back pain lose some elements of proprioception, although research in this area is relatively new. One aspect of proprioception, repositioning accuracy, was examined in this study. The primary purpose of this study was to compare repositioning accuracy of individuals with CLBP and healthy controls. Specifically, the ability to reposition the pelvis into a neutral position was examined in standing and seated positions. A secondary purpose of the study was to examine the inter-relationships between low back pain, repositioning accuracy and physical measurements. The ability to repositioning the pelvis into neutral in both standing and seated positions was tested in 19 volunteers aged 35-55 years old from the University of Tennessee at Knoxville and surrounding community. The participants were divided into two groups based on their Oswestry Low Back Pain Disability Questionnaire score (ODQ). Individuals with an ODQ score of zero were placed in the control group (n = 10). The chronic low back pain group (CLBP; n = 9) included individuals with an ODQ score greater than zero. The groups were similar with regards to age, height, weight, and body mass index. An electronic goniometer (elgon) was used to measure total lumbar range of motion (TROM), baseline neutral position, and neutral repositioning in both standing and seated positions. Each participant underwent a neutral spine training session following anthropometric, flexibility and strength measurements. Standing TROM was calculated as the sum of extreme anterior tilt and extreme posterior tilt. Following TROM testing, baseline standing neutral spine position was recorded for each individual. The participants then attempted to replicate their standing neutral position. Repositioning error was calculated as the absolute difference between the baseline neutral position and the repositioned neutral position. The same protocol was repeated in an unsupported seated position. The results of the repeated measures ANOVA demonstrated no significant differences in repositioning accuracy between the CLBP group and the healthy control group in either standing or seated positions. However, there was a significant difference between the standing and seated positions for the sample (p \u3c 0.05). Overall, for all subjects, the mean absolute repositioning error was greater in a seated position than in standing. In addition, the groups were no statistically different in TROM or baseline neutral positions in either standing or seated positions. To examine the difference in lumbar lordosis before and after neutral spine training, a single factor (time) repeated measures ANOVA was performed on the measurements obtained with the flexible ruler. There was a significant time effect for both the CLBP and control groups; the lumbar lordosis measures were significantly reduced with neutral spine posture. The between group effect was not significant. MANOVA indicated significant differences between the groups for trunk extension strength and abdominal strength. In both cases the CLBP group had statistically weaker trunk extension and trunk flexion strength

An Evaluation of passive recumbent quantitative fluoroscopy to measure mid-lumber intervertebral motion in patients with chronic non-specific low back pain and healthy volunteers.

Introduction: The biomechanical model of back pain has failed to find distinct relationships between intervertebral movement and pain due to limitations and variation in methods, and errors in measurement. Quantitative fluoroscopy (QF) reduces variation and error and measures dynamic intervertebral motion in vivo. This thesis used recumbent QF to examine continuous mid-lumbar intervertebral motion (L2 to L5) in patients with assumed mechanical chronic non-specific low back pain (CNSLBP) that had been clinically diagnosed. It aimed to develop kinematic parameters from the continuous data and determine whether these could detect subtle mechanical differences by comparing this to data obtained from healthy volunteers. Methods: This was a prospective cross sectional study. Forty patients with CNSLBP (age 21 to 51 years), and 40 healthy volunteers matched for gender, age and body mass index underwent passive recumbent QF in the coronal and sagittal planes. The patient group completed questionnaires for pain and disability. Four kinematic parameters were developed and compared for differences and diagnostic accuracy. Reference intervals were developed for three of the parameters and reproducibility of two were assessed. The radiation dose was compared to lumbar spine radiographs and diagnostic reference levels were established. Finally, relationships between patient’s pain and disability and one of the kinematic parameters (continuous proportional motion CPM) were explored. Results: Reproducibility was high. There were some differences in the coronal plane and flexion for each kinematic parameter, but no consistency across segments and none had high diagnostic accuracy. Radiation dose for QF is of the same magnitude as radiographs, and there were no associations between patient characteristics of pain and disability and CPM. Conclusion: Although the kinematic differences were weak, they indicate that biomechanics may be partly responsible for clinically diagnosed mechanical CNSLBP, but this is not detectable by any one kinematic parameter. It is likely that other factors such as loading, central sensitisation and motor control may also be responsible for back pain that is considered mechanical. QF is easily adapted to clinical practice and is recommended to replace functional radiography, but further work is needed to determine which kinematic parameters are clinically useful

Current Advances in Spinal Diseases of Elderly Patients

The rapid aging of populations in developed countries since the 2000s has placed increasing attention on the issue of musculoskeletal disorders in elderly patients. Notably, spinal disorders not only restrict the social activities of elderly patients, but they also lead to economic loss for society. “Current Advances in Spinal Diseases of Elderly Patients” is a topical collection of articles about current perspectives on diagnosis and treatment of spinal disorders including current surgical strategies. This Special Issue covers a broad range of issues, ranging from managing refractory states such as severe osteoporosis, spinal deformity, ossification of the spinal ligaments, and multiple arthropathy to managing lifestyle-related spinal diseases during the COVID-19 pandemic in elderly populations. We hope that the readers of this Special Issue find the contents interesting

Computed-Tomography (CT) Scan

A computed tomography (CT) scan uses X-rays and a computer to create detailed images of the inside of the body. CT scanners measure, versus different angles, X-ray attenuations when passing through different tissues inside the body through rotation of both X-ray tube and a row of X-ray detectors placed in the gantry. These measurements are then processed using computer algorithms to reconstruct tomographic (cross-sectional) images. CT can produce detailed images of many structures inside the body, including the internal organs, blood vessels, and bones. This book presents a comprehensive overview of CT scanning. Chapters address such topics as instrumental basics, CT imaging in coronavirus, radiation and risk assessment in chest imaging, positron emission tomography (PET), and feature extraction

Intervertebral Disc Regeneration II

This book is devoted to the thriving research on the regeneration of intervertebral discs. It is a colorful mixture of different applied science fields with the shared aim of reducing the number of lower back pain surgeries worldwide. I thank all contributors for submitting their manuscripts to this Special Issue who made this project a success

Diseño de técnicas de inteligencia artificial aplicadas a imágenes médicas de rayos X para la detección de estructuras anatómicas de los pulmones y sus alteraciones

[ES] El ojo humano de los radiólogos es altamente preciso y ha sido muy entrenado durante los últimos años. Sin embargo, cuando se utilizan imágenes médicas para detectar enfermedades, hay ciertos cambios que son muy sutiles (a nivel de píxel) y permanecen ocultos a la interpretación visual. Por este motivo, el objetivo principal del trabajo es la aplicación de técnicas de inteligencia artificial (¿machine learning¿ o ¿deep learning¿) para la detección de estructuras anatómicas y sus alteraciones en el tejido pulmonar mediante adquisiciones de rayos X de tórax. Se va a emplear Matlab para desarrollar un sistema clasificador de imágenes mediante técnicas de machine learning, entrenado con imágenes de rayos-x de pulmón de distintas bases de datos libres. Finalmente se va a finalizar el trabajo probando el sistema con imágenes del PACS del Hospital Unversitario y Politécnico La Fe de Valencia.Fos Guarinos, B. (2016). Diseño de técnicas de inteligencia artificial aplicadas a imágenes médicas de rayos X para la detección de estructuras anatómicas de los pulmones y sus alteraciones. http://hdl.handle.net/10251/70103.TFG

An Observational study of changes in cervical inter-vertebral motion and the relationship with patient-reported outcomes in patients undergoing spinal manipulative therapy for neck pain.

Spinal manipulation is a commonly sought therapy for neck pain. The present work examined sagittal plane cervical inter-vertebral kinematics in patients and healthy volunteers to explore whether motion is different in patients with neck pain, if manipulation is associated with changing cervical kinematics, and if changes are related to patient-reported outcomes. A standardised quantitative fluoroscopy (QF) image acquisition protocol for the cervical spine was developed and tested. A model of a cervical segment with a rigidly fitted digital inclinometer was rotated in the sagittal plane whilst being fluoroscopically imaged and QF results were compared for accuracy to that of the inclinometer. QF imaging sequences from ten subjects were analysed twice, six weeks apart, to assess repeatability. Finally, 30 patients and 30 age/gender-matched healthy volunteers had two cervical spine QF assessments four weeks apart. Only patients received spinal manipulation and completed patient-reported outcome measures (PROMs). Kinematic variables of interest included IV-RoM, segmental hypo-mobility, paradoxical motion, instantaneous axis of rotation (IAR) location, and laxity/attainment rate. The acquisition protocol allowed for imaging sequences to be achieved in a manner acceptable to participants. QF was found to be accurate to 0.5° for rotational range of motion. Intra- and inter-observer repeatability studies revealed substantial agreement and reliability for the QF measurement of C1 to C6 rotational motion (largest standard error of measurement (SEM) = 1.14°, lowest intra-class correlation coefficient (ICC) = 0.895) but not for IAR location (largest SEM = 7.66mm, lowest ICC = -0.080). Agreement and reliability were moderate-substantial for laxity/attainment rate (largest SEM = 0.04, lowest ICC = 0.70). There were no significant differences at baseline between patients and healthy volunteers in IV-RoM, or in the number of hypo-mobile, paradoxical or lax motion segments. Spinal manipulation was weakly associated with IV-RoM increases above the minimum detectable change calculated from healthy volunteers, in a dose response manner (Rho = 0.39 (95% CI: 0.014 to 0.663) p = 0.04). While the majority (87%) of patients reported clinically significant reductions in pain and disability