Mark Rzeszotarski | Case Western Reserve University (original) (raw)

Papers by Mark Rzeszotarski

ABSTRACT LEARNING OBJECTIVES 1. Understand technique of brain perfusion imaging using 64-slice CT... more ABSTRACT LEARNING OBJECTIVES 1. Understand technique of brain perfusion imaging using 64-slice CT scanner. 2. Review advantages and limitations of this new technology with respect to tissue coverage and sensitivity for infarcts and ischemic penumbra in larger volumes of the brain. ABSTRACT MDCT perfusion imaging of the brain provides a rapid method for assessing patients presenting with stroke. Information regarding viable versus non-viable brain tissue can alter treatment in the acute phase by influencing decisions regarding systemic and intra-arterial thrombolysis. This technique has been made practical with the advent of multi-detector row CT scanners. These scanners permit rapid data acquisition during multiple phases of contrast enhancement. The newest generation of multi-detector row CT scanners is capable of acquiring 64 slices in one rotation. This translates into a broader area of anatomic coverage, up to four centimeters. Using "Jog" type techniques, coverage can be doubled to eight centimeters. This increased coverage of brain tissue increases sensitivity to smaller, more peripheral areas of infarct or ischemic penumbra.

ABSTRACT PURPOSE To analyze the wait times for screening and diagnostic mammograms in various are... more ABSTRACT PURPOSE To analyze the wait times for screening and diagnostic mammograms in various areas of the country. METHOD AND MATERIALS Both academic and community hospitals/imaging centers were contacted, and a standard script was used to obtain information regarding the wait times for screening and diagnostic mammograms. RESULTS Preliminary results have been obtained from contacting 10 institutions in Ohio and 11 institutions in California. In Ohio, the wait time for a screening mammogram ranged from 1-12 days, with an average wait time of 3.8 days, while the wait time for a diagnostic mammogram was 1-14 days, with an average wait time of 4.4 days. In California, the wait time for a screening mammogram ranged from 1-60 days, with an average wait time of 25.7 days, while the wait time for a diagnostic mammogram was 1-69 days, with an average wait time of 21.1 days. Overall, the average wait time for a screening mammogram was 15.3 days, and the average wait time for a diagnostic mammogram was 13.1 days. CONCLUSION Initial results show a nearly equivalent wait time for screening and diagnostic mammograms. We plan to expand this study to involve additional states and regions of the country. CLINICAL RELEVANCE/APPLICATION Knowledge regarding the wait times for mammographic examinations allows institutions to implement methods to decrease the wait time and better serve the patient population.

Typescript. Department of Biomedical Engineering. Thesis--Case Western Reserve University.

LEARNING OBJECTIVES 1) To review the different methodologies used for constructing exposure chart... more LEARNING OBJECTIVES 1) To review the different methodologies used for constructing exposure charts. 2) To comprehend the importance of accurate exposure charts in computed radiography. 3) To understand the challenges presented with exposure charts designed specifically for computed radiography. ABSTRACT Exposure charts are an essential quality assurance component of a diagnostic x-ray imaging department. These exposure guides are especially important in computed radiography (CR), where the wide exposure latitude makes it possible to obtain clinical images which are severely underexposed, resulting in noisy images, or overexposed, resulting in possible data clipping as well as high patient doses. This exhibit reviews the different types of exposure charts and provides guidance on how to construct an exposure chart for optimal CR imaging based on the signal, noise and radiation scatter characteristics of CR equipment. Tradeoffs in speed settings for pediatric and adult imaging, the us...

Clinical nuclear …, 1988

Magnetic resonance imaging (MRI) was compared with radionuclide scintigraphy (RNS) in 16 patients... more Magnetic resonance imaging (MRI) was compared with radionuclide scintigraphy (RNS) in 16 patients with renal transplants undergoing renal failure to determine which modality could best discriminate between rejection, acute tubular necrosis (ATN), and cyclosporin ...

Radiographics, 1999

Factors affecting patient dose in all x-ray imaging modalities include beam energy, filtration, c... more Factors affecting patient dose in all x-ray imaging modalities include beam energy, filtration, collimation, patient size, and image processing. In conventional radiography, the most important determinant of acceptable patient dose is use of the highest peak kilovoltage that results ...

Radiographics : a review publication of the Radiological Society of North America, Inc

The low radiation dose rates used in nuclear medicine necessitate image formation and measurement... more The low radiation dose rates used in nuclear medicine necessitate image formation and measurements that are severely count limited. This limitation may mask our ability to perceive contrast in an image or may affect our confidence in quantitative functional measurements. The randomness of the signal can be described by using the Poisson probability distribution with its associated mean and variance. The validity of a measurement and uncertainties in a result can be determined by examining the count statistics. If multiple measurements are used to derive a result, confidence levels can be determined by examination of the propagation of errors. The statistical properties of the detected signal can also be evaluated to determine if the equipment is functioning properly. For example, the chi2 test can be used to determine if there is too much or too little variability in count samples. Finally, image formation with limited numbers of photons results in noisy images that may be difficult...

Optical Engineering, 1984

The variance of a bar pattern image can be used to measure the modulation transfer function (MTF)... more The variance of a bar pattern image can be used to measure the modulation transfer function (MTF) of an imaging system. This method is often simpler and more practical than conventional methods. The theoretical basis of the method is derived, and verification is provided by computer simulations. The computer simulations also are used to evaluate the accuracy of approximate formulas. The MTF of a computed tomographic (CT) scanner is measured to illustrate the technique.

Behavior Research Methods & Instrumentation, 1983

Neurophysiological and psychophysical evidence indicates that the visual system performs a sort o... more Neurophysiological and psychophysical evidence indicates that the visual system performs a sort of Fourier analysis of retinal variations in brightness through multiple spatial frequencytuned channels. Two types of applications of techniques of two-dimensional Fourier analysis are discussed: (1) modeling and simulation of visual functions. and (2) generation of stimuli in which the spatial frequency information is controlled. Examples of both these applications are presented.

Behavior Research Methods & Instrumentation, 1983

PURPOSE/AIM The purpose of this exhibit is to: 1) Demonstrate the most useful angles and lines th... more PURPOSE/AIM The purpose of this exhibit is to: 1) Demonstrate the most useful angles and lines that can be used in evaluating hand and wrist radiographs. 2) Describe, using clinical examples, how the measurements assist in determining the pathology. CONTENT ORGANIZATION Normal radiographic anatomy is reviewed first. Following this, diagrams demonstrating the radial length, radial inclination, volar tilt, radial shift, carpal arcs, scapholunate angle, capitolunate angle, scapholunate interval, carpal height ratio, ulnar variance, ulnar translocation, carpal angle, metacarpal sign, radial deviation, and ulnar deviation are shown. Normal values, a description of the uses, and an abnormal example of each type of measurement are also presented. SUMMARY Conventional radiographs are often used as a starting point in the evaluation of acute and chronic abnormalities of the hand and wrist in the emergency and outpatient settings. A great deal of information can be obtained before proceeding ...

PURPOSE/AIM * To review the billing costs of radiology examinations * To review what patients fin... more PURPOSE/AIM * To review the billing costs of radiology examinations * To review what patients financially owe a county hospital based on how much they earn and whether they have insurance * To review negotiated payments by insurance companies for radiology exams * To discuss future costs based on new technological advances CONTENT ORGANIZATION * Current costs of radiology examinations - MRI, CT, CR/DR, Nuclear Medicine, Interventional examinations - Trends of what costs were in the past and what they are today * Financial obligations patients are expected to fulfill * What insurance companies will pay * Emerging technologies and their expected corresponding costs SUMMARY * The current costs of radiology examinations are more significant than clinicians expect, and it is important to understand these costs when ordering a radiology exam * When a patient is employed but has little or no insurance, they may be responsible for a very large radiology bill * Insurance companies can consid...

PURPOSE/AIM The purpose of this exhibit is to describe several of the graphical tools most common... more PURPOSE/AIM The purpose of this exhibit is to describe several of the graphical tools most commonly used in quality improvement using examples from quality improvement projects frequently encountered in a radiology department. CONTENT ORGANIZATION The content organization will lead the reader through a series of useful quality improvement visualization tools: Cause-Effect Diagrams, Flow Diagrams, Scatter Plots, Histograms, Time Data Series, Bar Charts, Pareto Charts and Control Charts. SUMMARY The major teaching points of this exhibit include: 1. Comprehend the scope of quality improvement tools available to aid in understanding a process. 2. Decide which tools are most useful for your specific application. 3. Examine the advantages of representing information visually using control charts.

PURPOSE/AIM The aims of this exhibit are to: 1. Describe the AAPM/RSNA Education Task Force, whic... more PURPOSE/AIM The aims of this exhibit are to: 1. Describe the AAPM/RSNA Education Task Force, which is developing web-based modules for radiologic science education of residents and radiologists. 2. Encourage physicists, residents and radiologists to participate in the development of these modules to provide easily accessible, low cost education for all. CONTENT ORGANIZATION This exhibit describes an AAPM/RSNA joint initiative to create web-based radiologic science educational materials. A request for proposals to develop these modules has been issued. 25-30 modules will be developed in phase 1 with more in phase 2. Each module must have a physicist and a radiologist as authors. The intention is to make these modules image-rich with a clinical emphasis. Two modules have been developed: CT Dose and another on Interventional Dose and Safety. Funding has been approved SUMMARY The major teaching points of this exhibit include: 1. A request for proposals has been published, requesting phy...

PURPOSE/AIM The purpose of this exhibit is to: 1. Explain how control charts can be used to provi... more PURPOSE/AIM The purpose of this exhibit is to: 1. Explain how control charts can be used to provide a visual interpretation of data; 2. Review the different types of data; 3. Contrast the various types of control charts and describe how to select the appropriate chart; and 4. Learn to recognize trends, outliers and excess variation in a process. CONTENT ORGANIZATION Introduction to control charts: what they are used for. Types of data used in Radiology (attribute and variable). Example of a control chart: how to construct it and what information it provides. Types of control charts and how to select the right one. How to interpret a control chart: trends, outliers, excess variability, processes in control versus out of control. SUMMARY This exhibit will use simulated examples of processes frequently monitored in Radiology. The major teaching points of this exhibit are: 1. Comprehend how the use of a control chart can provide rapid visual interpretation of data that may not otherwise...

ABSTRACT LEARNING OBJECTIVES 1. Understand technique of brain perfusion imaging using 64-slice CT... more ABSTRACT LEARNING OBJECTIVES 1. Understand technique of brain perfusion imaging using 64-slice CT scanner. 2. Review advantages and limitations of this new technology with respect to tissue coverage and sensitivity for infarcts and ischemic penumbra in larger volumes of the brain. ABSTRACT MDCT perfusion imaging of the brain provides a rapid method for assessing patients presenting with stroke. Information regarding viable versus non-viable brain tissue can alter treatment in the acute phase by influencing decisions regarding systemic and intra-arterial thrombolysis. This technique has been made practical with the advent of multi-detector row CT scanners. These scanners permit rapid data acquisition during multiple phases of contrast enhancement. The newest generation of multi-detector row CT scanners is capable of acquiring 64 slices in one rotation. This translates into a broader area of anatomic coverage, up to four centimeters. Using "Jog" type techniques, coverage can be doubled to eight centimeters. This increased coverage of brain tissue increases sensitivity to smaller, more peripheral areas of infarct or ischemic penumbra.

ABSTRACT PURPOSE To analyze the wait times for screening and diagnostic mammograms in various are... more ABSTRACT PURPOSE To analyze the wait times for screening and diagnostic mammograms in various areas of the country. METHOD AND MATERIALS Both academic and community hospitals/imaging centers were contacted, and a standard script was used to obtain information regarding the wait times for screening and diagnostic mammograms. RESULTS Preliminary results have been obtained from contacting 10 institutions in Ohio and 11 institutions in California. In Ohio, the wait time for a screening mammogram ranged from 1-12 days, with an average wait time of 3.8 days, while the wait time for a diagnostic mammogram was 1-14 days, with an average wait time of 4.4 days. In California, the wait time for a screening mammogram ranged from 1-60 days, with an average wait time of 25.7 days, while the wait time for a diagnostic mammogram was 1-69 days, with an average wait time of 21.1 days. Overall, the average wait time for a screening mammogram was 15.3 days, and the average wait time for a diagnostic mammogram was 13.1 days. CONCLUSION Initial results show a nearly equivalent wait time for screening and diagnostic mammograms. We plan to expand this study to involve additional states and regions of the country. CLINICAL RELEVANCE/APPLICATION Knowledge regarding the wait times for mammographic examinations allows institutions to implement methods to decrease the wait time and better serve the patient population.

Typescript. Department of Biomedical Engineering. Thesis--Case Western Reserve University.

LEARNING OBJECTIVES 1) To review the different methodologies used for constructing exposure chart... more LEARNING OBJECTIVES 1) To review the different methodologies used for constructing exposure charts. 2) To comprehend the importance of accurate exposure charts in computed radiography. 3) To understand the challenges presented with exposure charts designed specifically for computed radiography. ABSTRACT Exposure charts are an essential quality assurance component of a diagnostic x-ray imaging department. These exposure guides are especially important in computed radiography (CR), where the wide exposure latitude makes it possible to obtain clinical images which are severely underexposed, resulting in noisy images, or overexposed, resulting in possible data clipping as well as high patient doses. This exhibit reviews the different types of exposure charts and provides guidance on how to construct an exposure chart for optimal CR imaging based on the signal, noise and radiation scatter characteristics of CR equipment. Tradeoffs in speed settings for pediatric and adult imaging, the us...

Clinical nuclear …, 1988

Magnetic resonance imaging (MRI) was compared with radionuclide scintigraphy (RNS) in 16 patients... more Magnetic resonance imaging (MRI) was compared with radionuclide scintigraphy (RNS) in 16 patients with renal transplants undergoing renal failure to determine which modality could best discriminate between rejection, acute tubular necrosis (ATN), and cyclosporin ...

Radiographics, 1999

Factors affecting patient dose in all x-ray imaging modalities include beam energy, filtration, c... more Factors affecting patient dose in all x-ray imaging modalities include beam energy, filtration, collimation, patient size, and image processing. In conventional radiography, the most important determinant of acceptable patient dose is use of the highest peak kilovoltage that results ...

Radiographics : a review publication of the Radiological Society of North America, Inc

The low radiation dose rates used in nuclear medicine necessitate image formation and measurement... more The low radiation dose rates used in nuclear medicine necessitate image formation and measurements that are severely count limited. This limitation may mask our ability to perceive contrast in an image or may affect our confidence in quantitative functional measurements. The randomness of the signal can be described by using the Poisson probability distribution with its associated mean and variance. The validity of a measurement and uncertainties in a result can be determined by examining the count statistics. If multiple measurements are used to derive a result, confidence levels can be determined by examination of the propagation of errors. The statistical properties of the detected signal can also be evaluated to determine if the equipment is functioning properly. For example, the chi2 test can be used to determine if there is too much or too little variability in count samples. Finally, image formation with limited numbers of photons results in noisy images that may be difficult...

Optical Engineering, 1984

The variance of a bar pattern image can be used to measure the modulation transfer function (MTF)... more The variance of a bar pattern image can be used to measure the modulation transfer function (MTF) of an imaging system. This method is often simpler and more practical than conventional methods. The theoretical basis of the method is derived, and verification is provided by computer simulations. The computer simulations also are used to evaluate the accuracy of approximate formulas. The MTF of a computed tomographic (CT) scanner is measured to illustrate the technique.

Behavior Research Methods & Instrumentation, 1983

Neurophysiological and psychophysical evidence indicates that the visual system performs a sort o... more Neurophysiological and psychophysical evidence indicates that the visual system performs a sort of Fourier analysis of retinal variations in brightness through multiple spatial frequencytuned channels. Two types of applications of techniques of two-dimensional Fourier analysis are discussed: (1) modeling and simulation of visual functions. and (2) generation of stimuli in which the spatial frequency information is controlled. Examples of both these applications are presented.

Behavior Research Methods & Instrumentation, 1983

PURPOSE/AIM The purpose of this exhibit is to: 1) Demonstrate the most useful angles and lines th... more PURPOSE/AIM The purpose of this exhibit is to: 1) Demonstrate the most useful angles and lines that can be used in evaluating hand and wrist radiographs. 2) Describe, using clinical examples, how the measurements assist in determining the pathology. CONTENT ORGANIZATION Normal radiographic anatomy is reviewed first. Following this, diagrams demonstrating the radial length, radial inclination, volar tilt, radial shift, carpal arcs, scapholunate angle, capitolunate angle, scapholunate interval, carpal height ratio, ulnar variance, ulnar translocation, carpal angle, metacarpal sign, radial deviation, and ulnar deviation are shown. Normal values, a description of the uses, and an abnormal example of each type of measurement are also presented. SUMMARY Conventional radiographs are often used as a starting point in the evaluation of acute and chronic abnormalities of the hand and wrist in the emergency and outpatient settings. A great deal of information can be obtained before proceeding ...

PURPOSE/AIM * To review the billing costs of radiology examinations * To review what patients fin... more PURPOSE/AIM * To review the billing costs of radiology examinations * To review what patients financially owe a county hospital based on how much they earn and whether they have insurance * To review negotiated payments by insurance companies for radiology exams * To discuss future costs based on new technological advances CONTENT ORGANIZATION * Current costs of radiology examinations - MRI, CT, CR/DR, Nuclear Medicine, Interventional examinations - Trends of what costs were in the past and what they are today * Financial obligations patients are expected to fulfill * What insurance companies will pay * Emerging technologies and their expected corresponding costs SUMMARY * The current costs of radiology examinations are more significant than clinicians expect, and it is important to understand these costs when ordering a radiology exam * When a patient is employed but has little or no insurance, they may be responsible for a very large radiology bill * Insurance companies can consid...

PURPOSE/AIM The purpose of this exhibit is to describe several of the graphical tools most common... more PURPOSE/AIM The purpose of this exhibit is to describe several of the graphical tools most commonly used in quality improvement using examples from quality improvement projects frequently encountered in a radiology department. CONTENT ORGANIZATION The content organization will lead the reader through a series of useful quality improvement visualization tools: Cause-Effect Diagrams, Flow Diagrams, Scatter Plots, Histograms, Time Data Series, Bar Charts, Pareto Charts and Control Charts. SUMMARY The major teaching points of this exhibit include: 1. Comprehend the scope of quality improvement tools available to aid in understanding a process. 2. Decide which tools are most useful for your specific application. 3. Examine the advantages of representing information visually using control charts.

PURPOSE/AIM The aims of this exhibit are to: 1. Describe the AAPM/RSNA Education Task Force, whic... more PURPOSE/AIM The aims of this exhibit are to: 1. Describe the AAPM/RSNA Education Task Force, which is developing web-based modules for radiologic science education of residents and radiologists. 2. Encourage physicists, residents and radiologists to participate in the development of these modules to provide easily accessible, low cost education for all. CONTENT ORGANIZATION This exhibit describes an AAPM/RSNA joint initiative to create web-based radiologic science educational materials. A request for proposals to develop these modules has been issued. 25-30 modules will be developed in phase 1 with more in phase 2. Each module must have a physicist and a radiologist as authors. The intention is to make these modules image-rich with a clinical emphasis. Two modules have been developed: CT Dose and another on Interventional Dose and Safety. Funding has been approved SUMMARY The major teaching points of this exhibit include: 1. A request for proposals has been published, requesting phy...

PURPOSE/AIM The purpose of this exhibit is to: 1. Explain how control charts can be used to provi... more PURPOSE/AIM The purpose of this exhibit is to: 1. Explain how control charts can be used to provide a visual interpretation of data; 2. Review the different types of data; 3. Contrast the various types of control charts and describe how to select the appropriate chart; and 4. Learn to recognize trends, outliers and excess variation in a process. CONTENT ORGANIZATION Introduction to control charts: what they are used for. Types of data used in Radiology (attribute and variable). Example of a control chart: how to construct it and what information it provides. Types of control charts and how to select the right one. How to interpret a control chart: trends, outliers, excess variability, processes in control versus out of control. SUMMARY This exhibit will use simulated examples of processes frequently monitored in Radiology. The major teaching points of this exhibit are: 1. Comprehend how the use of a control chart can provide rapid visual interpretation of data that may not otherwise...