Medical Diagnostic Imaging Research Articles

Morphological Variation of Fissure and Lobe of the Left Lung: A Case Report

Abstract The left lung usually has an oblique fissure that divides it into superior and inferior lobes. Some variants in the lobar fissure are well known, but the knowledge of certain uncommon variants will enhance our anatomical understanding and proper identification of the bronchopulmonary segments. Several imaging techniques have been used to describe anatomical variations of the lung, but studies that utilize dissections as tools for understanding lobar variations were limited. In this report, we described an incomplete horizontal fissure, bifurcated accessory fissure, incomplete superior and middle lobes, and fibrous condensation of the left lung pulmonary pleura observed during dissection. The knowledge of these anatomical variations will be useful in surgical segmental resection and lobectomy, and for accurate interpretations of medical diagnostic images.

Multicystic Dysplastic Kidney and Sonography

Multicystic dysplastic kidney is a congenital anomaly that can affect the kidneys. It is generally unilateral and is characterized by multiple noncommunicating cysts in the renal parenchyma. This disease usually results in an enlarged, nonfunctioning kidney in the neonate. Recent advances in diagnostic medical imaging, especially in sonography, have enabled earlier detection of this disease, created better management and treatment options, and resulted in improved outcomes for patients. This case study demonstrates the use of early detection with sonography and the utilization of it for follow-up care. Sonography is ranked as the imaging modality of choice for patients with a clinical condition of renal failure and has the potential for an improved outcome for patients.

Acoustic Holographic Rendering with Two-dimensional Metamaterial-based Passive Phased Array.

Acoustic holographic rendering in complete analogy with optical holography are useful for various applications, ranging from multi-focal lensing, multiplexed sensing and synthesizing three-dimensional complex sound fields. Conventional approaches rely on a large number of active transducers and phase shifting circuits. In this paper we show that by using passive metamaterials as subwavelength pixels, holographic rendering can be achieved without cumbersome circuitry and with only a single transducer, thus significantly reducing system complexity. Such metamaterial-based holograms can serve as versatile platforms for various advanced acoustic wave manipulation and signal modulation, leading to new possibilities in acoustic sensing, energy deposition and medical diagnostic imaging.

Laser-driven resonance of light-absorbing ultrasound contrast microbubbles

The sensitivity of ultrasound imaging is greatly enhanced by the use of microbubble contrast agents through resonant volumetric oscillations. While the increased acoustic contrast is of prime interest for perfusion imaging of organs, microbubbles until now have limited benefit in terms of specificity for ultrasound imaging. Original strategies are required to tackle this difficulty that rely on loading functional targeting ligands onto the microbubble encapsulation. In parallel, laser light offers great specificity in its interaction with tissue. This advantage is put to use in photoacoustic imaging where absorbed laser light is converted into a measurable acoustic signal. Here, we present a novel ultrasound contrast agent designed to make use of the specificity of laser light. The acoustic agent consists of a gas core encapsulated by an oil layer containing an absorbing dye. The resulting laser light absorption can then be used to heat up the gas and drive the system into resonance, thereby generating ultrasound. Combining finite difference simulations and ultra high-speed imaging led to a quantitative physical description of the optical and thermal interactions in the system resulting in the efficient generation of acoustic waves in the MHz range. A range of physical bubble parameters are investigated, i.e., thickness and composition of the light absorbing oil layer. This new generation of contrast agents will open up new applications in medical diagnostic and therapeutic imaging.

Image Fusion of Multi-Modal Images using Region Consistency Check and Blocking in Contourlet Transform

Objectives: The purpose of medical image fusion is to obtain more useful content from different imaging modalities. Region consistency check fusion rule is applied in Contourlet Transform with blocking methodology for better diagnosis. Methods: Here, features of Contourlet Transform along with Wavelet transform have been studied. Simulation experiments have been done on multimodality images. Two source images are decomposed into multi-resolutions by applying concept of Contourlet transform. Transformed coefficients will be integrated with a fusion rules. After that, CT with blocking has been applied. In blocking process similarity between temporary fused image and original image has been find out. Lastly best result has been considered using sign matrix. Finding: CT, which provides a good directionality than the others transforms. Quantitative and qualitative analysis of our proposed algorithm shows that using blocking in CT with region consistency check fusion rule gives more informative image. Novelty/Improvement: The results show that it is useful for enhancing medical imaging for medical diagnostics and analysis.

Flow visualization of simple pipe and channel flows obtained by MRI time-slip method

Herein, time-resolved magnetic resonance imaging, a noninvasive medical diagnostic imaging technique, was evaluated as a noncontact measurement tool for intuitively understanding fluid machineries. Simple pipe flows and channel flows are investigated by the 2D time–spatial labeling inversion pulse (2D time–SLIP) method, which can track a labeled water mass and visualize it using two-dimensional images. In this article, moving water masses of steady and pulsating pipe flows in a straight single pipe and a double cylindrical pipe (which are often seen in fluid machines and heat exchangers) are described. Then, abruptly contracting and expanding channels were tested and compared with particle image velocimetry (PIV) measurements or numerical simulations to evaluate their validity. In addition, as a feasibility test, a rotating water wheel and a fluidic diode with a strong swirling flow were tested to estimate this method’s applicability to fluid machines. The results suggest that the time-SLIP method of tracking a labeled water mass is sufficiently accurate for use in simple fluid machinery under low Re number conditions.

Fiber pixelated image database

Imaging of physically inaccessible parts of the body such as the colon at micron-level resolution is highly important in diagnostic medical imaging. Though flexible endoscopes based on the imaging fiber bundle are used for such diagnostic procedures, their inherent honeycomb-like structure creates fiber pixelation effects. This impedes the observer from perceiving the information from an image captured and hinders the direct use of image processing and machine intelligence techniques on the recorded signal. Significant efforts have been made by researchers in the recent past in the development and implementation of pixelation removal techniques. However, researchers have often used their own set of images without making source data available which subdued their usage and adaptability universally. A database of pixelated images is the current requirement to meet the growing diagnostic needs in the healthcare arena. An innovative fiber pixelated image database is presented, which consists of pixelated images that are synthetically generated and experimentally acquired. Sample space encompasses test patterns of different scales, sizes, and shapes. It is envisaged that this proposed database will alleviate the current limitations associated with relevant research and development and would be of great help for researchers working on comb structure removal algorithms.

Super-Resolution via Sparse Representation for Low-dose X-ray Photography

The diagnostic medical imaging has provided enormous benefits in the early detection as well as the potential side effect of radiation induced genetic diseases. The super-resolution analysis is pro...

Nanoparticulate Contrast Agents for Multimodality Molecular Imaging.

Molecular imaging is rapidly developing as a powerful tool in research and medical diagnostic. By integrating complementary signal reporters into a single nanoparticulate contrast agent, multimodal molecular imaging can be performed as scalable images with high sensitivity, resolution and specificity. In this review, multifunctional nanoparticles (MFNPs) are classified into four types: conjugation, encapsulation, core/shell, and co-doping. Further, new constructs of MFNPs were reported recently which have used nanoparticulate contrast agent such as quantum dots (QDs), iron oxide nanoparticles (IONPs), Upconversion nanoparticles (UCNPs), carbon based nanoparticles, gold nanoparticles (Au-NPs), Metal-Organic Frameworks (MOFs), dendrimers and porphyrins based nanoparticles. Different surface modification strategies were also developed as well as ligands are attached to those NPs to render the biocompatibility and enable specific targeting. These new development in MFNPs are expected to introduce a paradigm shift in multi-modal molecular imaging and thereby opening up an era of personalized medicine and new diagnostic medical imaging tools.

Study on the relation between tissues pathologies and traditional chinese medicine syndromes in knee osteoarthritis: Medical image diagnostics by preoperative X-ray and surgical arthroscopy.

This study aims to investigate whether integration of traditional Chinese medicine and modern medicine has advantage in achieving the improved diagnosis and treatment of knee osteoarthritis. 90 patients with knee osteoarthritis were selected from The Department of Minimal Invasive Joint of The Third Affiliated Hospital of Beijing University of Chinese Medicine from June 2013 to June 2015. They were divided into 3 groups with 30 cases per group in accordance to the syndrome differentiation of traditional Chinese medicine. The patients underwent arthroscopic surgery, and we categorized the patients having the same characterization in each group, and those having distinct difference into the three groups. Based on the arthroscopic analysis, we performed analysis of statistical data in order to analyze the relation between knee osteoarthritis under arthroscope and traditional Chinese medicine syndromes. There are three syndromes according to traditional Chinese medicine that can be categorized into various different groups. The synovial proliferation can be seen mostly in the syndrome of stagnation of blood stasis. The slight damage of knee joint cartilage can be seen in the syndrome of yang deficiency and cold stagnation, the severe one in the syndrome of kidney-marrow deficiency. We found that there are different pathological expressions with the various degree of the tissues damage at the knee and we categorized the knee according to their syndrome. For knee osteoarthritis, different syndromes of traditional Chinese medicine presents different tissues pathological changes at the knee joint under arthroscopy, which will provide objective basis for the diagnosis of this medical condition.

Trends and Developments Shaping the Future of Diagnostic Medical Imaging: 2015 Annual Oration in Diagnostic Radiology.

For acceptance of innovative new methods into practice, the imaging community will need to increase its emphasis on assessing not just the intrinsic quality or accuracy of new methods but their capacity to ultimately help achieve societal goals of more patient centeredness of care, better patient outcomes, and improved cost effectiveness in resource utilization.

The Relevance and Limitations of the Imaging Diagnosis in Dogs ʼNeurological Disorders

The purpose of this paper is to emphasise the importance of the clinical exam in the evaluation of dogs with neurological disorders. A strict evaluation of this group of dogs during the clinical examination conduces to a more rapid diagnosis, reducing the risk of radiation and unnecessary costs by using the modern medical imaging techniques. Dogs from different breeds, of different ages and sex were examined. After the typical clinical procedures, for all the animals a neurological examination was performed. Once we have received the owner’s consent, basic blood biochemistry and haematology was performed. The VITAMIND protocol was mandatory for each dog. In order to establish the final diagnosis, the dogs were examined by imaging techniques or by other tests (e.g. for endocrynopathies). Further the dogs were treated systematically with appropriate drugs. The results show that all the diagnoses of the examined dogs can be confirmed by imaging and/or other techniques (physical examination methods), depending on the disease’ etiology. In order to have a correct and quick diagnosis of animals with neurological disorders, a certain examination protocol should be followed. The effectiveness of the treatments was different, according to the specific disease. Taking everything into account, the diagnostic medical imaging techniques are very important but not always necessary. Precious time is saved when the examining physician is able to evaluate and interpret the clinical signs obtained by the animal inspection.

Teleradiology service for mission hospitals: initial experiences in Ethiopia and Kenya

Throughout their history, mission hospitals have provided high quality and lifesaving medical care to regions of the world where medical care is sparse. These hospitals are generally built and equipped through a combination of governmental and non-governmental sources. As advances in diagnostic medical imaging have progressed and become mainstream in the developed world, mission hospitals have adopted advanced imaging modalities. These modalities provide early diagnosis and treatment options for their patients. In addition to the installation and operation of advanced imaging equipment, the need for professional expert interpretation of these studies remains a challenge for mission hospitals. Historically these hospitals have used either voluntary services on site or paid for interpretations from local radiologists; however, with the introduction of high speed internet, teleradiology has become a possibility. This article describes the teleradiology experience of two mission hospitals in rural Africa.

Current status of medical radiation exposure in Korea - recent efforts to develop a radiation exposure control system focussed on justification and optimisation.

Radiation exposure from diagnostic medical imaging has increased in Korea. Radiological societies play a key role in radiation safety issues in Korea, including guidelines, accreditation, advocacy, scientific activity, and education. Any medical radiation exposure must be justified, and examinations using ionising radiation must be optimised. Education of referring physicians and radiologists is also important for justification. Medical physicists and radiographers have an important role to play in quality management and optimisation. Regulations are essential to control medical radiation exposure. Therefore, national organisations have made a significant effort to regulate and monitor medical radiation exposure using guidelines, accreditation, and even the law. Medical radiation exposure must be controlled, and this could be achieved by continuous interest from health professionals and organisations.

Theoretical and Monte Carlo optimization of a stacked three-layer flat-panel x-ray imager for applications in multi-spectral medical imaging.

We propose a new design of a stacked three-layer flat-panel x-ray detector for dual-energy (DE) imaging. Each layer consists of its own scintillator of individual thickness and an underlying thin-film-transistor-based flat-panel. Three images are obtained simultaneously in the detector during the same x-ray exposure, thereby eliminating any motion artifacts. The detector operation is two-fold: a conventional radiography image can be obtained by combining all three layers' images, while a DE subtraction image can be obtained from the front and back layers' images, where the middle layer acts as a mid-filter that helps achieve spectral separation. We proceed to optimize the detector parameters for two sample imaging tasks that could particularly benefit from this new detector by obtaining the best possible signal to noise ratio per root entrance exposure using well-established theoretical models adapted to fit our new design. These results are compared to a conventional DE temporal subtraction detector and a single-shot DE subtraction detector with a copper mid-filter, both of which underwent the same theoretical optimization. The findings are then validated using advanced Monte Carlo simulations for all optimized detector setups. Given the performance expected from initial results and the recent decrease in price for digital x-ray detectors, the simplicity of the three-layer stacked imager approach appears promising to usher in a new generation of multi-spectral digital x-ray diagnostics.

Abstract WP387: Outcomes of a Wake-up Stroke Protocol

Background: Patients who present with stroke symptoms upon awakening, often referred to as wake-up stroke (WUS), account for approximately 25% of acute ischemic strokes. In this group, onset time is unknown. Due to the unknown time of onset, patients with WUS are often excluded from consideration of aggressive stroke treatment and are generally treated with routine medical management only. However, through the use of advanced imaging and rapid interpretation of findings, we have found that selected WUS patients may benefit from endovascular stroke therapies. We identified the need for a standardized protocol to ensure that all WUS patients are urgently assessed as candidates for aggressive management. Purpose: The purpose of this project was to establish a standardized protocol, including a one-call alert system and pre-set orders for advanced diagnostic imaging, to be used in the quick determination of a treatment plan for patients presenting with WUS. Methods: A protocol was created by the stroke team. The stroke team responds to the one-call alert system, advanced diagnostics are rapidly performed, and a decision regarding endovascular treatment is made by the Interventional Radiologist. Education was provided to all major stakeholders including all Neurologists, Emergency Department Physicians and staff, Radiologists, Stroke Nurse Practitioners, Emergency Medical Providers, Diagnostic Imaging and Special Procedures staff. Wake-Up Stroke alert activations, procedures, and outcomes are monitored by the Stroke Coordinator. Results: Wake Up Stroke Protocol was published for use in February 2015. Within the 90-day period immediately following, 16 Stroke Alert activations were called for WUS patients. Eight of the 16 were deemed to be candidates for endovascular stroke therapy. Of the eight patients treated, the average improvement in NIHSS score is 5.5 points (range 0-14). Conclusion: In conclusion, the WUS Protocol is effective in the rapid identification of patients who could benefit from endovascular stroke therapies.

Decision tree based medical image clustering algorithm in computer-aided diagnoses

With the rapid development of intelligent diagnostic medical imaging, artificial intelligent methods have become a research hotspot in this field with the rapid development of medical imaging intelligent diagnosis. The new research progress of artificial intelligence in medical image processing in recent five years is discussed. This paper discussed the function of medical image mining in computer-aided diagnoses. The idea of using luminance grade as the features of CT image and the method of extracting and storing the luminance grade are proposed. The results of classification based on decision tree and clustering based on density to some brain and breast CT images and the analysis to them are introduced. Moreover, the conclusion and future work are given.

Personal exposure to static and time-varying magnetic fields during MRI procedures in clinical practice in the UK

BackgroundMRI has developed into one of the most important medical diagnostic imaging modalities, but it exposes staff to static magnetic fields (SMF) when present in the vicinity of the MR...

50 Years Ago in TheJournal ofPediatrics: Effects of Ionizing Radiation in Children

Sutow WW, Conard RA. J Pediatr 1965;67:658-71 This review article, published 50 years ago in The Journal, examined the effects of ionizing radiation on children. At the time of writing, limited scientific data was available regarding the effects of low-dose radiation, an important source of which is medical diagnostic imaging. Although emerging evidence did suggest an increased risk of developing leukemia and malignant neoplasia among children exposed in utero to diagnostic doses of radiation, not all studies supported such finding. Estimates of potential harmful effects of low-dose radiation were mainly based on assumptions and extrapolations from adult data and reports on high-dose exposure. Nonetheless, physicians back then had already taken a more cautious and conservative approach in the use of radiation in both diagnostic and therapeutic procedures. Robust and valid evidence is now accumulating to ascertain the harmful effects of low-dose ionizing radiation on children. A recent retrospective cohort study demonstrated significant associations between the estimated radiation doses provided by computed tomography (CT) scans to bone marrow and brain and subsequent incidence of leukemia and brain tumors. Cumulative ionizing radiation doses from 2 to 3 head CT scans could almost triple the risk of brain tumors and 5 to 10 head CT scans could triple the risk of leukemia.1Pearce M.S. Salotti J.A. Little M.P. McHugh K. Lee C. Kim K.P. et al.Radiation exposure from CT scans in childhood and subsequent risk of leukemia and brain tumors: a retrospective cohort study.Lancet. 2012; 380: 499-505Abstract Full Text Full Text PDF PubMed Scopus (2578) Google Scholar Advanced imaging is a remarkable resource but the need for the scan has to be balanced against the potential harm. All procedures and especially those that may involve significant radiation need to be justified. Other diagnostic means, which do not involve ionizing radiation, should be considered if appropriate. Monitoring patient radiation exposure is the way forward. It is only by measuring the doses that are being delivered that physicians can begin to do their utmost to keep the doses as low as possible, and to avoid unnecessary or repeated scans.

Monte Carlo reference data sets for imaging research: Executive summary of the report of AAPM Research Committee Task Group 195

The use of Monte Carlo simulations in diagnostic medical imaging research is widespread due to its flexibility and ability to estimate quantities that are challenging to measure empirically. However, any new Monte Carlo simulation code needs to be validated before it can be used reliably. The type and degree of validation required depends on the goals of the research project, but, typically, such validation involves either comparison of simulation results to physical measurements or to previously published results obtained with established Monte Carlo codes. The former is complicated due to nuances of experimental conditions and uncertainty, while the latter is challenging due to typical graphical presentation and lack of simulation details in previous publications. In addition, entering the field of Monte Carlo simulations in general involves a steep learning curve. It is not a simple task to learn how to program and interpret a Monte Carlo simulation, even when using one of the publicly available code packages. This Task Group report provides a common reference for benchmarking Monte Carlo simulations across a range of Monte Carlo codes and simulation scenarios. In the report, all simulation conditions are provided for six different Monte Carlo simulation cases that involve common x-ray based imaging research areas. The results obtained for the six cases using four publicly available Monte Carlo software packages are included in tabular form. In addition to a full description of all simulation conditions and results, a discussion and comparison of results among the Monte Carlo packages and the lessons learned during the compilation of these results are included. This abridged version of the report includes only an introductory description of the six cases and a brief example of the results of one of the cases. This work provides an investigator the necessary information to benchmark his/her Monte Carlo simulation software against the reference cases included here before performing his/her own novel research. In addition, an investigator entering the field of Monte Carlo simulations can use these descriptions and results as a self-teaching tool to ensure that he/she is able to perform a specific simulation correctly. Finally, educators can assign these cases as learning projects as part of course objectives or training programs.