Focusing on one projection per page, Bontrager's Textbook of Radiographic Positioning and Related Anatomy, 9th Edition includes all of the positioning and projection information you need to know in a clear, bulleted format. Positioning photos, radiographic images, and radiographic overlays, presented side-by-side with the explanation of each procedure, show you how to visualize anatomy and produce the most accurate images. Updated to reflect the latest ARRT competencies and ASRT curriculum guidelines, it features more than of the most commonly requested projections to prepare you for clinical practice.
Labeled radiographs radiographic overlays identify key radiographic anatomy and landmarks to help you recognize anatomy and determine if you have captured the correct diagnostic information on your images. Positioning chapters, organized with one projection per page, present a manageable amount of information in an easily accessible format. Unique page layout with positioning photos, radiographic images, and radiographic overlays presented side-by-side with the text explanation of each procedure to facilitate comprehension and retention.
Pathologic Indications list and define the pathologies most likely to be encountered during procedures covered in each chapter to help you understand the whole patient and improve your ability to produce radiographs that make diagnosis easy for the physician. Bontrager MA RT R This radiography text focuses on the most commonly performed radiographic exams as determined by an extensive survey. To help students better visualise and understand positioning, this text features one projection per page and a"show-and-tell" style that lines up explanation of the featured projection with positioning photos, radiographic images and anatomy line drawings.
This outstanding fifth edition includes an all new full colour design, new information on pathology, geriatric and paediatric patient populations, expanded survey information, and new positioning photographs for the latest in radiographic positioning. Nice Text in great shape By David Behymer text in almost new shape at a bargan price. Obese Patient Considerations include general information on positioning techniques and positioning modifications for obese patients to show you how to position this subset of patients accurately.
Routine and Special Procedures sections moved to an appendix so you can refer to this necessary material quickly and efficiently. Anatomy in Your Pocket 1st Edition. Sciubba Editor , Mark M. Mikhael Editor , Savvas Nicolaou Editor. Kagadis Editor , Nancy L. Ford Editor , Dimitrios N. Karnabatidis Editor , George K. Loudos Editor. Lowell Kahn Author , Christopher M. Gaskin Author , Victoria L. Sharp Author , Theodore E. Keats Author , Bing Li Author. Smith Author , Philip W.
Frank Author , Bruce W. Long Author. A Me dia l rota tion B La te ra l rota tion Fig. B, Lateral external rotation.
Another application of this term is the abduction of the ngers or toes, which means spreading them apart Fig. Adduction of the ngers or toes means moving them together or toward each other. This movement rotates the radius of the forearm laterally along its long axis. Abduction a wa y from A B Adduction towa rd Fig. B, Adduction. Supine or supination means face up or palm up, and prone or pronation means face down or palm down. Retraction is the opposite of this—that is, moving the jaw backward or squaring the shoulders, as in a military stance.
A B S upina tion P rona tion Fig. B, Pronation. A P rotra ction B Re tra ction Fig. B, Retraction. Depressing the shoulders is lowering them. This term describes sequential movements of exion, abduction, extension, and adduction, resulting in a cone-type movement at any joint where the four movements are possible e.
In Fig. Tilt is a slanting or tilting movement with respect to the long axis. Understanding the difference between these two terms is important in cranial and facial bone positioning see Chapter A B Fig. B, Depression. These terms should be understood and used correctly Table 1.
View describes the body part as seen by the IR or other recording medium, such as a uoroscopic screen. An example of a three-part radiographic image evaluation as used in this text for a lateral forearm is shown on the right. The positioning photo and the resulting optimal radiograph Figs. Va UaT n r T r a F r aT The technologist should review and compare radiographs using this standard to determine how close to an optimal image was achieved.
A systematic method of learning how to critique radiographs is to break the evaluation down into these th ee p ts. Anatom y dem onstrated: Describes precisely what anatomic parts and structures should be clearly visualized on that image radiograph.
Position: Generally evaluates four issues: 1 placement of body part in relationship to the IR, 2 positioning factors that are important for the projection, 3 correct centering of anatomy, and 4 collimation. Exposure: Describes how exposure factors or technique kilovoltage [kV], milliamperage [mA], and time can be evaluated for optimum exposure for that body part. Motion is included with exposure criteria because exposure time is the primary controlling factor for motion.
R Fig. Each image receptor IR should have a marker on the exterior indicating this area where the patient ID, including the date, will be identi ed. Throughout this text, the preferred location of this patient ID marker is shown in relation to the body part. A general rule for most chest studies is to place the patient ID information at the top margin of the IR on chests. The patient ID marker must always be placed where it is least likely to cover essential anatomy.
The anatomic side markers should always be placed in a manner on the IR so that they are legible and esthetically correct Fig. It must be within the collimation eld so that it provides a permanent indicator of correct side of the body or anatomic part.
B, Radiograph blue a rrow, Patient identi cation information; yellow a rrow, Anatomic side marker to indicate right wrist. Care must be taken so that this area does not obscure the essential anatomy that is being demonstrated. With digital imaging systems, patient identi cation is typically entered during registration and prior to exposure.
These radiopaque markers must be placed just within the collimation eld so that they will be exposed by the x-ray beam and included on the image. The two markers, the patient ID and the anatomic side marker, must be placed correctly on all radiographic images i clu i g igit lly p o uce im ges.
Generally, it is an unacceptable practice to write or annotate digitally this information on the image after it is processed because of legal and liability problems caused by iog ph t ke without these two potential mismarkings.
A m ke s m y h ve to be epe te , which results in unnecessary radiation to the patient, making this a serious error.
In the case of digital images, annotating the image to indicate side markers is an unacceptable practice. The exposure should be repeated to ensure the correct anatomy was imaged. Sometimes the examination room number is also included. Tim e i ic to s are also commonly used; these note the minutes of elapsed time in a series, such as the minute, minute, 1-hour, and 2-hour series of radiographs taken in a small bowel series SBS procedure see Chapter Another important marker on all decubitus positions is a decubitus marker or some type of indicator such as an ow i e tifyi g which si e is up.
Sample markers are shown in Fig. Code o ethics describes the ules of ccept ble co uct tow p tie ts othe he lth c e te m m em be s s well s pe so l ctio s beh vio s as de ned within the profession.
The a r T a campaign is an initiative to educate patients about the role of the radiologic technologist. ACE is an acronym to help you remember to share and gain important information with and from your patients Box 1. BOX 1. It is important for patients to understand that radiologic technologists are highly quali ed medical imaging professionals who are educated in patient positioning, radiation safety, radiation protection and equipment protocols.
Furthermore, patients should have an understanding of the medical imaging procedure they are undergoing. To communicate these points to patients, the American Society of Radiologic Technologists recommends that medical imaging professionals use the ACE initiative.
All rights reserved. Used with permission of the ASRT for educational purposes. The Code of Ethics shall serve as a guide by which Certi cate Holders and Candidates may evaluate their professional conduct as it relates to patients, healthcare consumers, employers, colleagues, and other members of the healthcare team.
The Code of Ethics is intended to assist Certi cate Holders and Candidates in maintaining a high level of ethical conduct and in providing for the protection, safety, and comfort of patients. The Code of Ethics is aspirational. The radiologic technologist acts in a professional manner, responds to patient needs, and supports colleagues and associates in providing quality patient care.
The radiologic technologist acts to advance the principal objective of the profession to provide services to humanity with full respect for the dignity of mankind. The radiologic technologist delivers patient care and service unrestricted by the concerns of personal attributes or the nature of the disease or illness, and without discrimination on the basis of sex, race, creed, religion, or socio-economic status.
The radiologic technologist practices technology founded upon theoretical knowledge and concepts, uses equipment and accessories consistent with the purposes for which they were designed, and employs procedures and techniques appropriately. The radiologic technologist assesses situations; exercises care, discretion, and judgment; assumes responsibility for professional decisions; and acts in the best interest of the patient.
The radiologic technologist acts as an agent through observation and communication to obtain pertinent information for the physician to aid in the diagnosis and treatment of the patient and recognizes that interpretation and diagnosis are outside the scope of practice for the profession. The radiologic technologist uses equipment and accessories, employs techniques and procedures, performs services in accordance with an accepted standard of practice, and demonstrates expertise in minimizing radiation exposure to the patient, self, and other members of the healthcare team.
The radiologic technologist continually strives to improve knowledge and skills by participating in continuing education and professional activities, sharing knowledge with colleagues, and investigating new aspects of professional practice. The ARRT does not review, evaluate, or endorse publications or other educational materials. Routine projections are de ned as p ojectio s com m o ly t ke o p tie ts who c coope te fully. This varies depending on radiologist and department preference and on geographic differences.
These are de ned as p ojectio s m ost com m o ly t ke to em o st te bette speci c tom ic p ts o ce t i p thologic co itio s o p ojectio s th t m y be ecess y fo p tie ts who c ot coope te fully.
The authors recommend on the basis of recent survey results that all students learn and demonstrate pro ciency for all essential projections as listed in this text. This includes all routine projections as well as all special projections as listed and described in each chapter. Examples of these routine projection and special projection boxes for Chapter 2 are shown. Becoming competent in these projections ensures that students are prepared to function as imaging technologists in any part of the United States.
Exceptions include an AP mobile portable chest, a single AP abdomen called a KUB—kidneys, ureter, and bladder , and an AP of the pelvis, in which only one projection usually provides adequate information. Three reasons for this general rule of a minimum of two projections are as follows: Fig. These are a P or Pa , l te l, and oblique p ojectio s. The reason for this rule is that more information is needed than can be provided on only two projections. For example, with multiple surfaces and angles of the bones making up the joint, a small oblique chip fracture or other abnormality within the joint space may not be visualized on either frontal or lateral views but may be well demonstrated in the oblique position.
Therefore, the technologist must rely on bony landmarks to indicate their location. These bony structures are m ks. Topographic landmarks can be located by a process referred to as palpation. Pa PaT n P lp tio refers to the process of applying light pressure with the ngertips directly on the patient to locate positioning landmarks. This m ust be o e ge tly because the area being palpated may be painful or sensitive for the patient. Also, the p tie t shoul lw ys be i fo m e of the pu pose of this p lp tio befo e this p ocess is begu , p tie t pe m issio shoul be obt i e.
Cre s t of ilium AS IS n T : Palpation of certain of these landmarks, such as the ischial tuberosity or the symphysis pubis, may be embarrassing for the patient and m y ot be pe m itte by i stitutio l policy. Technologists should use alternative landmarks as described in later chapters. S ymphys is pubis Gre a te r trocha nte r Is chia l tube ros ity Fig. In most cases, the long axis of the anatomic part is aligned to the longest dimension of the IR. This allows for the majority of an anatomic structure to be demonstrated and permits closer collimation of the x-ray eld to the anatomy.
The example in Fig. The IR is in the po t it le gthwise alignment in which the long axis of the lungs is aligned to the longest dimension of the IR.
In another case, the hypersthenic adult PA chest often requires the IR to be placed in sc pe c osswise alignment. This permits the broader the l lateral borders of the lung to be demonstrated Fig. For sc pe or po t it, will be each position in the text, the terms, l listed following the recommended size of IR to indicate how the IR should be aligned to the anatomic part. However, in the United States and Canada, a common and accepted way to place radiographic images for viewing is to display them so that the p tie t is f ci g the viewe , with the patient in the anatomic position Fig.
This is true for eithe a P o Pa p ojectio s Figs. One common method is to place the image so that the viewer is seeing the image from the same perspective as the x-ray tube.
Technologists should determine the preferred method for viewing laterals in their department. Images that include the digits hands and feet generally are placed with the igits up. However, other images of the limbs are viewed in the anatomic position with the lim bs h gi g ow Fig. Conventional lm-screen technology with the associated chemical processing and lm libraries is being replaced rapidly by digital technology.
Digital technology uses computers and x-ray receptors to acquire and process images; specialized digital communication networks are used to transmit and store the x-ray images. This period of technologic transition necessitates that students have an understanding of all image acquisition technologies because they will nd themselves working in imaging departments that acquire images by using only digital technology, only lmscreen technology, or a combination of both.
This part provides an introduction to radiographic technique and image quality for both lm-screen imaging and digital imaging. The study of radiographic technique and image quality includes factors that determine the accuracy with which structures that are being imaged are reproduced in the image.
Each of these factors has a speci c effect on the nal image, and the technologist must strive to maximize these factors to produce the best image possible at the lowest achievable dose. This part also describes methods of digital image acquisition, discusses the application of digital imaging, and provides an introduction to the important principles of radiation safety.
The image acquisition device is a lm-screen system that consists of a pair of intensifying screens with a lm between them. The screens and lm are housed in an x-ray cassette that protects the lm from light and ensures that screens are in close contact with the lm.
When screens receive the remnant radiation from the patient, they uoresce; this light exposes the lm, which must be chemically processed so the image can be viewed. Chemical processing includes several steps developing, xing, washing, and drying and typically takes 60 to 90 seconds. The lm image radiograph , which actually is composed of a deposit of metallic silver on a polyester base, is permanent; it cannot be altered. The various shades of gray displayed on the image are representative of the densities and atomic numbers of the tissues being examined.
The lm image is often referred to as a hard-copy image. Analog image receptors are best described as self-regulating systems with a limited dynamic range. Analog image receptors are also described using the term exposure latitude. Exposure latitude is the range of exposure over which a lm produces an acceptable image. An image produced with a level of exposure outside of the exposure latitude is an unacceptable image.
Note the impact of doubling the mAs on the diagnostic quality of the images of the elbow. Analog images have relatively narrow exposure latitude. T r n ,P T n n , an d acquisition technology. This can also be referred to as Kilovolt ge pe k kVp —the maximum electrical potential used to create the x-ray photons within the x-ray tube. When performing radiographic procedures, technologists must apply their knowledge of exposure factors and imaging principles to ensure that images obtained are of the highest qu lity possible, while exposing patients to the lowest i tio ose possible.
Film-based radiographic images are evaluated on the basis of fou qu lity f cto s. When a radiograph with high density is viewed, less light is transmitted through the image. The relationship for our purpose can be described as linear; doubling the mAs doubles the quantity or duration of x-rays emitted, thus doubling the density on the lm.
The distance of the x-ray source from the IR, or the sou ce im ge ecepto ist ce d , also has an effect on radiographic density according to the inverse square law. If the SID is doubled, at the IR, the intensity of the x-ray beam is reduced to one-fourth, which then reduces radiographic density to one-fourth.
A standard SID generally is used to reduce this variable. The radiograph of the elbow obtained with the use of 2 mAs shown in Fig. Doubling the mAs in this example resulted in doubling of the density on the radiograph. SID also should not require adjustment; it is a constant. Greater attenuation or absorption of x-rays occurs at the anode end because of the angle of the anode; x-rays emitted from deeper within the anode must travel through more anode material before exiting; thus, they are attenuated more.
The anode heel effect is more pronounced when a short SID and a large eld size are used. Applying the anode heel effect to clinical practice assists the technologist in obtaining quality images of body parts that exhibit signi cant variation in thickness along the longitudinal axis of the x-ray eld.
The patient should be positioned so that the thicke po tio of the p t is t the c tho e e of the x-ray tube and o e the cathode and anode the thi e p t is u e the ends of the x-ray tube usually are marked on the protective housing. The abdomen, thoracic spine, and long bones of the limbs e. A summary chart of body parts and projections for which the anode heel effect can be applied is provided in Table 1. In practice, the most common application of the anode heel effect is for anteroposterior AP projections of the thoracic spine.
This problem can be overcome through the use of compensating lters, which lter out a portion of the primary beam toward the thin or less dense part of the body that is being imaged. Several types of compensating lters are in use; most are made of aluminum; however, some include plastic as well. The type of compensating lter used by the technologist depends on the clinical application Fig.
This lter has numerous applications; the most common include AP foot, AP thoracic spine, and axiolateral projection of the hip. The thicker peripheral portions of the lter are placed to correspond to the anatomically less dense lungs; the thinner portion of the lter corresponds to the mediastinum.
Too little density underexposed or too much density overexposed does not adequately demonstrate the required structures. Correct use of the anode heel effect and compensating lters helps to demonstrate optimal lm density on anatomic parts that vary signi cantly in thickness. B Fig. When the density difference is large, the contrast is high, and when the density difference is small, the contrast is low.
This is demonstrated by the step wedge and by the chest radiograph in Fig. Contrast can be described as lo g-sc le or sho t-sc le co t st, referring to the total range of optical densities from the lightest to the darkest part of the radiographic image.
This is also demonstrated in Fig. Contrast allows the anatomic detail on a radiographic image to be visualized. Optimum radiographic contrast is important, and an understanding of contrast is essential for evaluating image quality. Low or high contrast is not good or bad by itself. For example, low contrast long-scale contrast is desirable on radiographic images of the chest.
Many shades of gray are required for visualization of ne lung markings, as is illustrated by the two chest radiographs in Figs. The low-contrast long-scale contrast image in Fig. The shades of gray that outline the vertebrae are less visible through the heart and the mediastinum on the high-contrast chest radiograph shown in Fig. In each of those circumstances, the technologist will need to make changes in the mAs settings in order to compensate for adjustment made for the change in contrast.
The higher the kV, the greater the energy, and the more uniformly the x-ray beam penetrates the various mass densities of all tissues. Therefore, highe kV produces less variation in attenuation differential absorption , resulting in lowe co t st. Higher kV, kV is also a seco resulting in both more numerous x-rays and greater energy x-rays, causes more x-ray energy to reach the IR, with a corresponding increase in overall density. In the lower kV range, such as 50 to 70 kV, an 8- to kV increase would double the density equivalent to doubling the mAs.
In the to kV range, a to kV increase is required to double the density. The importance of this relates to radiation protection because as kV is increased, mAs can be signi cantly reduced, resulting in absorption of less radiation by the patient.
The amount of scatter radiation the lm-screen receives in uences the radiographic contrast. Scatter radiation is radiation that has been changed in direction and intensity as a result of interaction with patient tissue.
The amount of scatter produced depends on the intensity of the x-ray beam, the amount of tissue irradiated, and the type and thickness of the tissue. Close collimation of the x-ray eld reduces the amount of tissue irradiated, reducing the amount of scatter produced and increasing contrast.
Close collimation also reduces the radiation dose to the patient and the technologist. Irradiation of thick body parts produces a considerable amount of scatter radiation, which decreases image contrast. A device called a grid is used to absorb much of the scatter radiation before it hits the IR. T r n ,P T n n , an d Grid s Because the amount of scatter increases with the thickness of the tissue irradiated, it generally is recommended that a grid should be used for radiography of any body part that is thicker than 10 cm.
Depending on the examination, the grid may be portable or may be built into the x-ray equipment. It is positioned between the patient and the IR and absorbs much of the scatter radiation before it hits the IR. Absorption of scatter is a key event that increases image contrast.
However, several rules must be followed to ensure optimal image quality when grids are used. Incorrect use of grids results in loss of optical density across all or part of the radiographic image; this feature is called grid cuto.
Grid cutoff occurs in various degrees and has several causes. Causes of grid cutoff include the following: 1. Off-center grid 3. Off-focus grid 2.
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