Film Critique of the CTL Spine - Part 1: Cervical Spine


Selected radiographs are critiqued for exposure, positioning, and diagnostic criteria.

Author: Nicholas Joseph Jr. RT(R) B.S. M.S

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Instructions:

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Diagnostic Criteria for Imaging the Horizontal Beam Lateral Cervical Spine

Diagnostic Criteria for Imaging the Swimmerís View of the Cervical Spine

Diagnostic Criteria for Imaging the AP Cervical Spine

Diagnostic Criteria for Imaging the Open-mouth Odontoid View of the Cervical Spine



Objectives:

Upon completion, the reader should be able to:

  • State the importance of a regular review of radiographs of the cervical spine using specific diagnostic criteria.
  • List the plain film radiographic views of the cervical spine taken for trauma series and for ambulatory imaging.
  • Give reasons why the Swimmerís view is used to demonstrate the lower cervical spine and particularly the cervicothoracic junction.
  • State the diagnostic criteria for the horizontal beam lateral cervical spine view.
  • State the diagnostic criteria for the horizontal beam lateral Swimmerís view.
  • State the importance of demonstrating the apophyseal joints of C7/T1 and the alignment at the cervicothoracic junction.
  • State the diagnostic criteria for the AP cervical spine view.
  • Give reasons why the AP view should be repeated if C3 is not adequately visualized.
  • State the diagnostic criteria for the open-mouth odontoid view of the cervical spine.
  • State what should be done to correct for poor positioning of the open-mouth view when the upper incisors are above and when below the base of the skull.
  • State the rationale for using the Fuchs view to demonstrate the odontoid tip, and tell why it is not an acceptable view for trauma imaging.
  • State how to properly position a patient for the cervical, thoracic, and lumbar spine views.
  • Discuss spine precautions and how to manipulate the x-ray tube for trauma imaging.
  • Describe why the central ray is often angled for the open-mouth odontoid view when the patient is on spine precautions.
  • State the relationships of the dens, spinous process, and spacing of the atlantoaxial joints when the head is not rotated.
  • Discuss the options when the cervicothoracic junction is not adequately demonstrated with the lateral spine radiographs.
  • Discuss the options when the open-mouth odontoid view is not adequately visualized with plain film imaging.
  • Discuss when a Swimmerís view should be taken and what should be demonstrated to complete the lateral visualization of the cervical spine.
  • Be able to identify specific anatomy on radiographs.

Radiographic Film Critique of the Cervical, Thoracic, and Lumbar Spines

Film Critique is a visual learning tool that allows the radiographer to understand the diagnostic criteria for each view in a radiographic series. Film critique is where professional imaging standards move beyond the classroom into real life imaging practice. This is a reverse learning session. You will see poorly made radiographs rather than optimal diagnostic radiographs. The purpose it to provide a discussion about what can be done to make better images. We face many circumstances where optimal positioning is not possible, for example during trauma surveys the ďas isĒ positioning is acceptable for spine imaging. While it is important to provide artful images, these do not always meet the diagnostic criteria. In this review the central focus is on diagnostic criteria for each radiographic view. To accomplish this you should be familiar with the pertinent anatomy, the affects of radiographic exposure factors like milliamperage and peak kilovoltage settings, and patient positioning. The imaging professional must decide if a film is truly useful as a diagnostic tool before it reaches the watchful eye of the radiologist who will use it for interpretation. Knowing the diagnostic standard for each film is of paramount importance where the goal is the presentation of useful images.






Introduction

Radiologic technologists make and view hundreds of thousands of films daily as part of our routine job performance. Providing radiologists with images suitable for interpretation requires both knowledge and skill. Knowing what is a diagnostic radiograph for all views presented is just part of what this critique is about. The task before each radiographic practitioner is acquiring the patience and skills to consistently make good radiographs. This exercise in film critique is designed to review the basic principles of applying diagnostic criteria to radiographic imaging. It is important that these standards be practiced uniformly throughout the discipline. Imaging textbooks generally emphasize what structures are mainly demonstrated with each view, the positioning of the part, and diagnostic criteria. Often as we get into the routine of imaging we forget to look at each image carefully to make sure we are complying with known standards. Knowing what is to be included in each view and the proper radiographic exposure technique for optimal subject detail are fundamental starting points for any discussion in film critique. As we view films in this module we will also address several important issues like what should be included in a specific view, how should that anatomy be presented radiographically, and is the radiographic exposure adequate for that view. It is the responsibility of the reader to know radiographic anatomy. You may need to review it just prior to beginning this critique exercise. The diagnostic criteria for each view are given in this lesson; however, bear in mind that the criteria must be met even if positioning is not optimal. Positioning is very patient dependent; however, it should be understood that less than optimal positioning could still meet the criteria for diagnosis. By diagnostic criteria we mean that the radiographic information meets minimum standards for diagnosis. The intent of this learning module is to reaffirm the practice of imaging according to diagnostic criteria rather than to a set of routinely practiced behaviors. For example, most textbooks reference the position of the part and the point of entrance of the central ray (CR) and its degree of tube angle. Standard radiographic practices are not always enough to meet the diagnostic criteria; however, not doing so will almost guarantee a poor quality image. This critique takes the approach of presented a radiograph for you to critique. Then the author discusses the radiograph to see how well you applied the diagnostic criteria to your critique. The goal is to use ďbadĒ images to discuss what should have been done or what is inadequate about the radiograph using the diagnostic criteria. By so doing you will be developing a concept of evaluating your radiographs to see if they meet standard criteria for interpretation. Following this practice you should transfer this practice to your images on patients your radiograph. You can also get a deeper appreciation for this module by also completing the modules ďTrauma imaging of the cervical, thoracic, and lumbar spines.Ē

Radiographic exposure technique and patient cooperation are very important factors in image quality. Likewise, not all images that are eye pleasing when casually viewed are diagnostic to the keen eye of a radiologist. Radiographer with experience must develop a sharper eye for viewing images for diagnostic quality. Paramount to viewing is the production of quality images time after time no matter how the patient presents. While most patients cooperate for imaging procedures there are times when a patient is too young to understand and cooperate, or the manifestation of alcohol abuse becomes a factor. Often language is a barrier to complete cooperation, as instructions may not be followed in a manner that optimizes imaging opportunities. Yet no specific circumstance inherently lowers or raises the bar against malfeasance or nonfeasance that haunts poor imaging and misdiagnosis that follows. Often with todayís shortages of radiologic technologists inexperienced practitioners are set on their own to clear images for interpretation without the close and precious benefit of ongoing critique by seasoned technologists. Notwithstanding, even seasoned experienced radiographers often repeat lateral cervical spine views due to under penetration of the part.

Furthermore, in order to evaluate any radiograph for technical excellence a solid foundation in how the four radiographic densities interplay based on exposure technique and patient composition is a must. In order to provide adequate density and subject contrast to maximize the visualization of bone, muscle, fat and air strong scientific principles must be embraced. Bone is the most radiopaque of these anatomic densities presenting as light areas on the film. Air gives radiolucent densities, which are dark on the radiograph. The viewing spectrum of these four radiographc densities creates a mosaic of varying densities seen as subject contrast and background density. A fifth density, metal, may be a part of the radiograph in the form of prosthetic implants, or an internal fixation, ands the like. When present, metal is also part of the subject contrast. Metal is more radiopaque than bone and is the main component of fixation devices. It is also the opacifying moiety in radiographic contrast agents like barium sulfate and iodinated contrast media. Using a contrast agent such as barium sulfate or iodine solutions allows us to demonstrate information about some structures better then if without it. For example, diagnostic details about some alimentary tract parts like the esophagus, stomach and colon are best seen using a contrast agent.

Evaluating images for density, subject contrast, image detail, and anatomical presentation is the proper way to conduct a film critique. Prior to submitting an image for interpretation make sure you are evaluating each image using the diagnostic criteria learned in this module. There are other authors whose perspective may vary slightly from that presented here; however, although the critique may vary for one person to another, the diagnostic criteria are constant from imager to imager. As we present many radiographs in the module it is our goal to improve youíre your ability to evaluate your radiographs and the skills it takes to produce consistent quality images. It is our hope that you will use the diagnostic criteria when commenting on images so that they become a part of your ongoing film critique in daily practice. Always consider that when we receive a prescription to administer a dose of radiation for diagnostic purpose that we are required to use as low as is reasonably achievable dose (ALARA). Therefore, the purpose of this critique is to teach principles consistent with proper planning of each view so that each exposure is a practice of the principle as low as reasonably achievable (ALARA). It is our goal to present many radiographs that tell the story of how to critique films in a way that encourages perfection of the diagnostic criteria by which we image.

  • This lesson is organized so that images are presented and then critiqued so as to promote effective learning.
  • Upon completion, you may take brief examination, which presents questions from samples of images.
Glossary of terms:
  • Overexposure (too much mAs)
  • Underexposure (too little mAs)
  • Overpenetrated (too much kVp)
  • Underpenetrated (too little kVp)
  • Positioning error (patient position)
  • Tube error (improper tube angle)




Trauma imaging of the cervical spine has specific diagnostic criteria that must be met in order to properly evaluate each patient. In addition to these radiographic standards, there are patient care standards that are practiced as spine precautions. For trauma imaging the patient presents on a spine board and in a cervical collar. Besides spine precautions there may be abdominal and pelvic precautions, and even precautions for extremities. Before aggressively imaging the spine the radiographer should get a good understanding of the patientís condition and their trauma score. Obviously you would not think of raising the arms to get a Swimmerís view on a patient with bilateral humerus and shoulder fractures. There are alternative methods for imaging these patients, mainly computerized tomography. But when requested, the standard views of the cervical spine are the horizontal beam lateral and Swimmerís view, AP, and open-mouth odontoid view.

The horizontal beam lateral is performed on every trauma patient presented with a cervical spine request. Until proven otherwise it is assumed that there is a vertebral fracture or dislocation. Both a lateral and a horizontal beam Swimmerís view are made to completely evaluate the entire cervical spine and cervicothoracic junction. The lateral view is generally the first image taken because it provides the most information about the spine quickly. In some institutions this view is requested as a portable survey. Others will stabilize the patient and bring them to the radiology department to complete all radiographic images at one time. Whatever the institutional procedure the lateral view is always a part of the trauma spine survey.

The lateral is followed by an AP view that may include the open-mouth odontoid view on patients that are conscious and not intubated. While these views are usually sufficient to evaluate the cervical spine the radiologist or emergency room physician may ask for additional views to complete the survey.

Diagnostic Criteria for Imaging the Horizontal Beam Lateral Cervical Spine

The horizontal beam lateral view of the cervical spine is taken when the patient has sustained an acute traumatic event. Victims of motor vehicle accidents, fall from heights, gunshot and penetrating neck injuries, diving injuries, just to mention a few present situations that warrant spine precautions. These patients are supported on a spine board with proper immobilizations to assure full spine precautions. The horizontal beam lateral of the cervical spine is the first image the radiographer should take to expedite the evaluation of the trauma patientís neck. For these patients the consequences and risk of injury including paralysis is real. Therefore, performing imaging protocols according to a safe set of diagnostic criteria is the radiographerís first duty. Below are the diagnostic criteria for imaging the cervical spine for both trauma situations and ambulatory imaging scenarios.

  • During trauma imaging a patient on a spine board should be given full spine precautions. Use the spine board to align the mid-sagittal plane (MSP) so that it is perpendicular to the horizontally directed central ray (CR). Always image the cervical spine of a trauma patient using a horizontal beam for all lateral views. These patients always remain supine recumbent and are manipulated using the spine board to align anatomical parts for imaging. The patientís body always remains in the so-called ďas isĒ position.
  • Never pull the arms or shoulders of a trauma patient attempting to demonstrate lower vertebra of the cervicothoracic junction. Instead, do bring the arms down to the sides if uninjured. Ask them to relax their shoulders into the spine board. Do not align the patientís head to correspond with the mid-sagittal plane if it is partially turned. The head must remain in the ďas isĒ position until the cervical spine is cleared. The two donít of trauma imaging of the cervical spine are: 1) do not pull down on the patientís shoulders or arms while attempting to demonstrate lower cervical vertebrae, 2) do not rotate the patientís head or body to position the upper cervical vertebrae.
  • All seven cervical vertebrae and the first thoracic vertebrae must be entirely demonstrated for all trauma views. In addition, the occiput, apophyseal joints of C1 through T1 must be demonstrated, and the posterior quadrilateral architecture of the vertebrae must be clearly seen. The complete anatomical presentation for interpretation includes from the occiput through the cervicothoracic junction. The three contour lines (anterior, posterior, and laminospinal lines) and in some cases all four contour lines must be drawn through the required anatomy.
  • Demonstrate the cervicothoracic junction (C7/T1) with a Swimmerís view when it is not fully appreciated on the horizontal beam lateral view alone. The three contour lines must also be demonstrated on the Swimmerís view. This is the proper way to demonstrate the lower cervical vertebrae and the cervicothoracic junction. If the Swimmerís view is inadequate, then you must consult with the radiologist who will recommend a CT scan.
  • Soft tissue structures such as the retropharyngeal space and airway should be visible on the radiograph without using a ďhot lightĒ or digital enhancements such as windowing and leveling the image. A careful balance between bone detail and soft tissue detail is a hallmark of a good radiographer. Soft tissue injury is a key indicator of trauma and cannot be neglected by poor or marginal radiographic exposure technique.
  • The radiographic exposure technique must demonstrate good bone architecture and detail. Adequate background density and subject contrast must be optimal for interpretation. An image that requires manipulation of digital data to make structures visible and lacks detail should be repeated. High contrast imaging of the bony spine is not recommended, especially if it results in a lack of penetration of bone. A well-penetrated bone window for digital imaging or a low contrast screen-film radiograph is recommended for spine imaging. Occasionally motion may be present on an image as a result of an uncooperative patient or long exposure times. It is sometimes difficult to get a radiograph of a ventilated patient completely free of motion. Image quality can suffer mildly from mechanical ventilation when using long exposure time. Excessive motion is unacceptable and measures must be taken before taking the radiograph to eliminate or diminish excessive motion. An uncooperative conscious patient may need a sedative or anti-anxiety medication to promote calmness. A ventilated patient may need to have ventilations temporarily stopped during the exposure by the respiratory therapist. When the patient is too uncooperative due to injury, alcohol, or drug use you should bring the issue to the attention of the ordering physician. Exposure technique to minimize patient motion should be selected at all times. Other measures include increasing the milliamperage (mA), decreasing the time of exposure (S), and compensatory use of high kVp.





Radiograph #1

image001 Consider this horizontal beam lateral radiograph of the cervical spine, has the diagnostic criteria for this radiograph been fulfilled? What would you suggest to improve the quality of this film and achieve the diagnostic standard for a lateral cervical spine view? Write down your comments and compare them to the diagnostic criteria above and the comments below!





Critique of Radiograph #1

image001

    When we compare what we see in this image to the diagnostic criteria stated above there are some concerns that need to be corrected:

  • Cervical vertebrae one through seven of this patient are easily demonstrated; however, the diagnostic criteria states that we should include from the base of the skull through the first thoracic vertebra. This criterion is not met on this radiograph. The apophyseal joints of C7/T1 are not adequately visualized. Vertebrae C1, C2, C7, and T1 are so underpenetrated that a fracture could be missed. The contrast scale is too high for spine radiography. Notice that the density of the air filled trachea is the same as the background density anterior to it. This is the result of the mAs being high and the beam too soft. A lower contrast exposure would differentiate the soft tissues from air better than is presented here.
  • We do not see the three contour lines through C7/T1. This makes it difficult to evaluate the alignment of the cervical and thoracic spine regions. This radiograph does have some value for the anatomy demonstrated so it should be kept and a more penetrated lateral should be added for interpretation.





Radiograph #2

image002 This horizontal beam lateral is taken on a trauma patient who is severely injured and is intubated. Do you think this radiograph presents enough information for diagnosis in this circumstance?

What do you think should be done to make it a better radiograph that fully meets the diagnostic criteria?





Critique of Radiograph #2

image002

    The technologist who made this radiograph considered it acceptable because C1-T1 and their apophyseal joints can be seen. The posterior bony quadrilateral architecture of each vertebra is also demonstrated. But because there is excessive motion due to high mechanical ventilation rate diagnostic detail cannot be gleaned from this picture. Subject detail too can be improved by using a shorter exposure time and a higher mA setting. Also having the respiratory therapist hold mechanical ventilations during the exposure will also cut down on motion. The safety pin holding the endotracheal tube should be moved a little more anterior to the spine, or replaced with tape during imaging. The radiographic technique chosen is adequate for this patient.






Radiograph #3

image003 The injuries on this film are quite obvious, but letís assume for a moment this is your patient and you donít know about these injuries. Also, your patient is unconscious.

Based on clinical presentation only, how should you handle this patient to achieve your radiographic imaging goals? What should be done to complete the diagnostic criteria for this trauma cervical spine lateral.





Critique of Radiograph #3

image003

    The compelling message of this radiograph is that it demonstrates why pulling down on the shoulders of any trauma patient for imaging the cervical spine is contraindicated. While imaging, always maintain spine precautions and a high suspicion for injury. Pulling down on the shoulders to help visualize C7/T1 junction is always contraindicated for acute trauma imaging. Ambulatory patients who are conscious and alert may bear weight for imaging, but never with trauma victims. The cervicothoracic junction is not demonstrated on this patient. A shoot through lateral rather than a swimmers view is indicated here because raising the arms of this patient is much too risky even for the Swimmerís view.

    Over collimation has restricted our view of the airway and other anterior soft tissue structures. This patient is intubated, but we cannot see the endotracheal tube on this radiograph because of over collimation. The entire anterior neck should be included during trauma imaging. With this type of injury more of the base of the skull should be demonstrated to evaluate relationships between the skull and spine.






Radiograph #4

image004 Do you think this radiograph meets its diagnostic criteria, or would you do something different to complete this view?






Critique of Radiograph #4

image004

    The technologist has demonstrated all 7 cervical vertebrae; however, the three contour lines are not seen through the 1st thoracic vertebra. This is due to a lack of optimal penetration at C7/T1. The most difficult part of the lateral cervical spine survey is to image the cervicothoracic junction. The apophyseal joints at C7/T1 appear to be intact; however, they are under penetrated. This leads to uncertainty in evaluating for fracture or dislocation. This is not due to the thickness of the shoulders as is usually the case. Notice that the shoulders are below the cervicothoracic junction. The opaqueness is strictly due to technique selection. The subject contrast is too high resulting in poor bone penetration. To complete this study a more penetrated lateral that shows detail through the apophyseal joints at C7/T1, or a Swimmerís view should be added. The pharyngeal structures, airway, and soft tissues of the neck are adequately seen.






Radiograph #5

image005 Does this radiograph meet the diagnostic criteria for a horizontal beam trauma lateral cervical spine view? If yes, what do you think is good about this radiograph, if no, what do you think is needed to complete the diagnostic criteria for this view?






Critique of Radiograph #5

image005
  • This lateral is well positioned. Notice that the mandibular condyles are superimposed on this trauma lateral view.
  • All apophyseal joints are superimposed, and the posterior quadrilateral architecture of all cervical vertebrae can be evaluated.
  • The junction of C7/T1 is seen, but is not adequately penetrated. It is these almost good radiographs that abut against the line of malfeasance.
  • The image is good for the pharyngeal shadow and airway. An appropriate amount of part collimation is also seen.
  • To complete this study a more penetrated lateral that shows detail through the apophyseal joints at C7/T1, or a Swimmerís view should be added.





Radiograph #6

image006 Consider this radiograph in which C7 is not visualized. Would you pull down on this patientís shoulders to see C7 through T1, why or why would you not? What else should be done to complete the diagnostic criteria for this view?






Critique of Radiograph #6

image006 No! Never pull down on the shoulders of a trauma patient!

    Notice there are bilateral jumped facets at C6/C5. The technologist does not need to be overly aggressive in this scenario; a consultation with the radiologist may be the best alternative after attempting a Swimmerís view. The three contour lines must be seen through T1 to complete the diagnosis, so add an overlapping Swimmerís view to include from T1 through C5. You donít need to be overly aggressive with plain film imaging since a CT scan may also be requested as well as an MRI scan. Again this is another example of why we must always maintain a high suspicion for injury for all trauma victims who may have sustained spine injury.

    The position marker should never be placed where it can obscure soft tissues. The anterior margins of the neck should be visualized when imaging the cervical spine. Blood or air in the neck fascia could indicate trauma elsewhere, such as a pneumothorax or hemorrhaging neck vasculature. So always include all of the soft tissues of the neck on cervical spine images.






Radiograph #7

image007 If this was your patient, and this is the image you got on your CTL trauma cervical spine view, what would you do next?





Critique of Radiograph #7 with Alternate Views #8 and #9

image007a
  • Weíve all had this type of difficult to image patient. Here only three proximal vertebrae are demonstrated on the lateral view. This lateral and two Swimmerís views bring home the point that you can shoot a lot of radiographs, but unless you can meet the diagnostic criteria for evaluating the spine your mission is incomplete.
  • Since pulling down on the shoulders of this patient is contraindicated, two Swimmerís views were attempted with marginal results.
  • Ultimately, only a CT scan will be able to contribute information sufficient for diagnostic clearance of this patientís spine. But what is important here is to inform the radiologist when you cannot achieve the diagnostic criteria for plain film interpretation without excessive repeat radiographs on this patient. Let the physician make the judgment call on what to do beyond your reasonable attempts to get good images.





Radiograph #10

image010 What is your critique of this radiograph? The background on the picture is that the patient was angry for having to wait 40 minutes to get radiographs and refused to remove her earrings. What would you do if your patient refuses to remove their earrings, necklace, etc? What is your critique of this film in this setting and how would you achieve the diagnostic standard?






Critique of Radiograph #10

image010

    The hallmark of a good radiographer is quality customer service. What this means for your relationship with the client in this scenario is that you must find a way to win them over, to cooperate in the production of their radiographs. You may need to show this unacceptable radiograph to your patient and tell them that you donít feel good about the quality of the study they have allowed you to make. Ask their permission to do it again correctly. And donít forget to apologize sincerely for their long wait. Acknowledging but not blaming yourself is the best way around this scenario. Taping the ears forward is not a good option here because the patient is able to cooperate.

    Did you also notice that the apophyseal joints of C7/T1 are barely visualized, and that vertebral alignment is not clearly seen through T1? Again the shoulders are obscuring what is really a good radiograph. When this radiograph is repeated have the patient depress their shoulders bringing them backwards. A little more kVp should be added to penetrate the cervicothoracic junction and demonstrate the three contour lines through T1.






Radiograph #11

image011 This is a "burned out" lateral radiograph in which the technologist tried to penetrate C7/T1 using an alternative view. The Swimmer's view is another alternative view to demonstrate the cervicothoracic junction.

Is this approach and film acceptable for diagnostic imaging interpretation?





Critique of Radiograph #11

image011a
  • Yes this is a good radiographic decision and resulting image. The so-called shoot through lateral is a more penetrated radiograph with excessive radiographic density and penetration through the part. In the picture to the left we see that the apophyseal joints of C7/T1 are clearly visible, the posterior bony quadrilateral architecture of C7 and T1 are well demonstrated. The three contour lines: anterior, posterior, and laminospinal can be drawn through T1.
  • The picture to the right is a magnification through the area of C7/T1. Notice the rib attachment to T1 and the well-penetrated apophyseal joints of C7/T1.
  • This view is actually more diagnostic than its more commonly done cousin the Swimmerís view because the humerus does not overshadow the spine.





Radiograph #12

image012 What is your critique of this radiograph, and what could have been done to make it a better image?






Critique of Radiograph #12

image012

    The most obvious improvements that can be made are the removal of the earrings and glasses. Donít try to get by with leaving earrings and glasses on because a repeat film means more exposure to the patient. Also the collimation for this view could be a little bit better. Collimation will improve radiographic contrast and reduce patient dose in keeping with ALARA. The radiologist can ignore the uniform streaks cause by the soft collar since it does not obstruct the anatomy.

    This patient is leaning slightly laterally towards the upright bucky. This may be an attempt to keep balanced while standing. The result is that the apophyseal joints are not superimposed. When this view is repeated sit the patient in a chair and reposition for a true lateral. Aligning the mid-sagittal plane parallel to the upright bucky will superimpose the apophyseal joints.






Radiograph #13

image013 This is obviously a good radiograph of the cervical spine. State reasons why this is a good radiograph, and tell if there is anything you would suggest to make it a better radiograph?





Critique of Radiograph #13

image013

    The good points to this radiograph are that: all seven cervical and first and second thoracic vertebrae are seen. Notice the cupola of the lungs extending above the thoracic inlet. The cupola is seen whenever the entire 1st thoracic vertebrae is demonstrated on a lateral view because it extends above the superior thoracic inlet. It is also important to see the apophyseal joints and posterior quadrilateral architecture of each vertebra. These are visualized entirely from the occiput through T2. The three contour lines can easily be drawn to reference alignment of the entire cervical spine and cervicothoracic junction.






Radiograph #14

image014 Consider this radiograph of a patient with a history for examination of: f/u interval changes, C2 fracture, check alignment.

Should anything be done to improve this radiograph?





Critique of Radiograph #14

image014

    This is an example of a radiograph in which the technologist does not need to include all of C7/T1 like in a trauma survey. This is a follow up (f/u) film to check alignment of C2 and the stability of the neck brace support. This is a good lateral by this scenario. When the patient history specifies f/u exam and the level of interest is specified, the diagnostic criteria applies to all vertebrae above the segment, and at least the entire vertebra below the segment. For example if C2 is specified, then the diagnostic criteria must at minimal include from the occiput through C3. However, the most common radiograph practice is to include the entire spine on all diagnostic plain film images.






Summary of the Lateral Cervical Spine Critique

  • What has been learned:
    1. A horizontal beam lateral is required for all trauma cervical spine images. The patient remain in the dorsal recumbent position until a radiologist and emergency room physician has cleared the spine.
    2. All cervical vertebrae from the occiput through the first thoracic vertebra must be seen. The contour of the vertebral bodies, apophyseal joints, posterior quadrilateral architecture, and bone trabecular patterns must be visualized.
    3. The radiographic technique must be adequate to differentiate between air, muscle, and bone.
    4. All of T1 to the occiput must be seen on the lateral view, or as a combination of views such as two laterals, or a lateral and Swimmerís view.
  • Apply your knowledge to each radiograph you take, asking did I meet the diagnostic criteria?




Diagnostic Criteria for Imaging the Swimmerís View of the Cervical Spine

  • Purpose is to demonstrate the cervicothoracic region with overlap of those cervical vertebrae not demonstrated on the horizontal beam lateral view. The Swimmerís view is indicated whenever the lateral view does not demonstrate all of C7 and T1, or when the thoracic spine lateral does not demonstrate C7 through T3.
  • With the patient on the spine board align the mid-sagittal plane (MSP) perpendicular to the horizontally directed central ray (CR). Occasionally the CR may be angled 5 degrees caudal when the patient is unable to depress the shoulder sufficiently to demonstrate T2. The patientís head and cervical spine are positioned true lateral unless spine precautions prohibit any movement of the patient.
  • The arm closest to the image receptor is raised and the opposite arm is depressed. The CR passes through the coricoid process of the scapula nearest the tube.
  • The apophyseal joints of C7/T1 and the posterior quadrilateral architecture must be demonstrated.
  • The three contour lines (anterior and posterior and laminospinal) must be visible throughout the entire cervical and first thoracic vertebrae. It is desirable to demonstrate from C5-T3 with T1 centered on the film.
  • The radiographic exposure technique should demonstrate good bone detail. To accomplish this a reduction in the scatter radiation reaching the film must be diminished. Tight collimation, a high grid ratio, and placing a lead strip along the posterior portion of the spine can significantly help in achieving this goal. For film screen imaging the kVp should be in the 80-90 ranges, and for CR/ddR in the 90-110 kVp ranges.





Radiograph #15

image015 Name this radiographic view.

Does it meet the diagnostic criteria for a lateral cervical view?

Why does it or does it not meet the criteria?





Critique of Radiograph #15

image015a
  • This is a coned Swimmerís view. It is a very good one in fact. Letís review the main reasons why it meets the diagnostic criteria for interpretation:
    1. The apophyseal joints of C7/T1 are well demonstrated (circle) with good subject contrast.
    2. The three contour lines can be drawn through the cervicothoracic junction.
    3. Motion due to long exposure technique did not grossly affect the diagnostic value of this image.
    4. Quality of the radiograph is not diminished by slight patient motion commonly seen with a long exposure.
  • Can you see all four points mentioned about this radiograph? The posterior ribs, apophyseal joints, and articular pillars are all seen without superimposition on each other. These are the hallmarks of a well-positioned Swimmerís view that is not rotated.





Radiograph #16

image016 Consider this radiograph of a Swimmerís view.

Is this an acceptable film, why or why not?





Critique of Radiograph #16

image016a
  • Again, this is a very good coned down Swimmerís view. The white arrow locates the first rib and first thoracic vertebra.
    1. The apophyseal joints of C7/T1 can be seen.
    2. The three contour lines can be drawn through T2.
    3. There is good bone detail for diagnostic evaluation.
  • Can you see all three points mentioned above in the radiograph?





Radiograph #17

image017 What could be done to improve this Swimmerís view?





Critique of Radiograph #17

image017

    It is important when using tight collimation or a cone that the part is aligned to the central ray. This radiograph has the part off centered so that the posterior margins of the spine are clipped. The humeral head of the left arm partially obscures anatomical structures. But this is a common finding with the Swimmerís view. Therefore, the shoulder should be brought backward towards the spine board as well as extended over the head. A little better centering may have been enough to provide better subject detail.

    Because of the positioning of the patient, the exact attachment of the 1st rib cannot be accurately determined. However, the apophyseal joints and posterior architecture of C7/T1 are adequately demonstrated. This view should be repeated because a good Swimmerís view is required for complete confident diagnosis of the cervicothoracic junction.






Radiograph #18

image018 Is this a good Swimmers view?

Which vertebrae is T1, and where are the apophyseal joints of C7/T1?





Critique of Radiograph #18

image018a

    Two reasons why it is difficult to determine which vertebra is T1 are under penetration of the part and positioning error. The long spinous process of C7 and the first thoracic spinous process are not easily identified due to part rotation. This also causes the apophyseal joints in the region of C7/T1 to not be superimposed. Strive to keep the patientís mid-sagittal plane aligned when one arm is raised and the other depressed. This may still be considered an adequate Swimmerís view, but is not optimal. What is lacking is clear visualization of both apophyseal joints of C7/T1 (white circle). We can see the superior and inferior alignment of the vertebrae at the cervicothoracic junction, which allows this radiograph to be marginally acceptable. The radiologist may have to work a little harder to appreciate the diagnostic value of this radiograph. Repeating this view to improve its value is suggested.






Radiograph #19

image019 Why do you think some radiologist require the full C-spine Swimmerís view over the coned down view? Does this Swimmerís view adequately meet the diagnostic criteria?






Critique of Radiograph #19

image019a

    Some radiologists prefer the full C-spine Swimmerís view because it is easier to count the vertebrae and determine which vertebrae are C7/T1 junction. Image detail is not as good since detail is enhanced by coning or tight collimation.

    Did you notice that the posterior arch of C1 is rotated (white arrow) and the apophyseal joints of the lower vertebrae are not well superimposed? This is because cervical spine is not aligned along the mid-sagittal plane. This can easily happen when raising one arm and depressing the other. Always check to see if the alignment has changed. Strive to not change the patientís alignment since the spine has not been cleared. An earring is seen that should have been removed.






Radiograph #20

image020 What could have been done to make this a better radiograph; tell whether or not it meets the diagnostic criteria for the Swimmerís view?





Critique of Radiograph #20

image020a

    This is a well-positioned radiograph that is optimally exposed. Obviously, the snap on the gown overshadows a portion of C7 and the quadrilateral architecture of C6. This is not an acceptable presentation of the Swimmerís view. Donít think that because the apophyseal joints of C7/T1 are well visualized this is an acceptable radiograph. A part of C7 is obscured by the metal snap. By now you should be pretty good at determining which vertebra is T1. Did you get it correct?






Critique of Radiograph #21

image021 Would you like a quick lesson on how to recognize C7 and T1 on the Swimmerís view?
  • First letís look at a CT slice through a thoracic vertebra and discuss its anatomy.
  • Notice that the rib has a joint articulation with the transverse process and the body of the vertebra (arrows). Remember these rib articulations because they are a factor when distinguishing the 1st thoracic vertebra on plain film.





Critique of Radiograph #22

image022
  • Next, observe that the 7th cervical vertebra has no rib attachment, and as its name (vertebra prominens) implies, it has a long spinous process that is not bifid (white arrow).
  • Notice the rib attachment to the first thoracic vertebra (long yellow arrow) by following it upwards. It is sometimes more difficult to see on the true lateral than on the Swimmerís view.
  • The apophyseal joints of C7/T1 so easily seen on this radiograph (short yellow arrow) must be seen on the Swimmerís view, which is a diagnostic criterion.





Radiograph #23

image023 Can you identify T1 and C7 on this radiograph?

Is it an acceptable radiograph, why or why not?





Critique of Radiograph #23

image023a
  • What makes this radiograph so difficult to critique is the poor subject contrast. While adequate penetration is demonstrated the graininess of the film suggests more mAs should be used and possibly an adjustment down in kVp. Close collimation will bring out better subject detail than the open collimation seen in this radiograph. The image suffers the type of fog seen with high kVp imaging and poor collimation.
  • To find T1 on this radiograph we must identify the 1st rib. It has an attachment to the manubrium at the clavicular notch anteriorly (white arrow). Just below it is the 1st costal cartilage where the 1st rib attaches. The yellow arrow indicates the first rib and T1. The apophyseal joints of C7/T1 are seen but without good subject contrast.





Summary of Swimmerís view Critique

  • What has been learned:
    1. Apophyseal joints of C7/T1 must be demonstrated along with the posterior quadrilateral architecture of all vertebrae.
    2. The radiologist must be able to evaluate the alignment of the vertebrae evidenced by three contour lines through the entire cervical spine and first thoracic vertebra.
    3. Adequate radiographic technique to evaluate for fractures.
  • Apply your knowledge to each radiograph you take, asking did I meet the diagnostic criteria?




Diagnostic Criteria for Imaging the AP Cervical Spine

  • Align the mid-sagittal plane (MSP) to the vertically directed central ray (CR). The CR is angled 15-20 degrees cephalic. A properly angled CR will open the intervertebral disk spaces and project the spinous processes near the inferior intervertebral disk space.
  • All of T1 through C3 must be demonstrated. This can be accomplished by extending the chin, or by tube angulation. Trauma imaging protocol does not permit the repositioning of the cervical spine by rotating, extension, or flexion.
  • The lateral margins including the skin lines must be demonstrated. A transverse field size of no less than 6 inches is recommended, and the position marker placed 3 or more inches from the cassette center.
  • Radiographic technique must be adequate to evaluate the vertebral bodies, spinous processes, articular pillars, and trabecular pattern of bone. For the AP view the optimal kVp range is between 70-80.





Radiograph #24

image024 Can you state the diagnostic criteria for the AP view of the cervical spine and tell whether it is meet on this film? How many cervical vertebrae should be seen on an AP view, considering that the neck cannot be extended during trauma imaging?






Critique of Radiograph #24

image024
  • The diagnostic standard for the AP cervical spine view includes:
    1. Demonstration of vertebrae C3 through T1, even if the patient is in a cervical collar. All soft tissues of the neck should be included on the AP view. Especially the lateral margins of the skin should be included. As technologist, we should recognize that tissues like the pre-cervical fascia are important to radiographic diagnosis. This information is not completely included on the left lateral margin of this film. The lateral margins must include the skin line for trauma imaging. Occasionally these tissues give clues to other injuries and the spine appearing normal. The diagnostic radiographer must be aware of the importance here and include all tissues of the neck.
    2. Radiograph density should include good penetration of the entire spine. Especially the area over C3 where soft tissues around the mandible tend to obscure bony detail.
  • Did you notice that the lateral margins of the film are over collimated? Important soft tissues of the neck and its precervical fascia are important to radiographic diagnosis. This radiograph should be repeated.





Radiograph #25

image025 Is this a good AP cervical spine radiograph? Base your answer on evaluating it according to the diagnostic criteria?





Critique of Radiograph #25

image025

    This radiograph demonstrates the required anatomy, which is from C3 inferiorly through T3. . The soft tissues along the lateral margins are included on the film. Radiographic technique is adequate for bone and soft tissues. Making this a very good radiograph.






Radiograph #26

image026 What could be done to improve the quality of this radiograph?





Critique of Radiograph #26

image026
  • In this example we see hairpins that should have been removed. Even when imaging seriously injured trauma patients metal such as earrings and necklaces should be removed before making radiographic exposures. Realistically speaking, there may be times when exception to removing items may occur. For example, when the patient is in a cervical collar appropriately strapped to a spine board, and items cannot be safely removed. In such case an ďas isĒ image should be done first. These images may need to be repeated later.
  • Did you notice that this image has very high subject contrast? It is too high to demonstrate C3 and the spine under the chin. Many technologists have trouble with the proper kVp setting for the AP view. The key to technique selection is the visualization of C3. If positioning allows for the demonstration of C3 then the radiographic technique should also! Use it to determine if the radiographic technique is correct. This radiograph should be repeated using an increased kVp to penetrate the mandible and demonstrate C3. The mAs may need to be lowered to compensate for the increase in density of the overall image. Variable mAs with kVp between 75-80 is recommended.





Radiograph #27

image027 What do you think about this radiograph, does it meet the diagnostic criteria? What can be done to make this a better radiograph?





Critique of Radiograph #27

image027a

    If you identified this radiograph as having a positioning error then you are correct. No amount of radiographic technique can compensate for the poor positioning seen here. The distance between the angle of the mandible and mastoid is too great (white arrows). These structures should be superimposed when positioning is correct. Small distances can be compensated for by tube angulation or repositioning the part. The standard tube angle is 15-20 degrees cephalic. This patient is not in a cervical collar; therefore, the technologist should have extended the chin more to demonstrate C3. This radiograph does not meet the diagnostic criterion of including a well-penetrated visualization of C3. Otherwise it would have met the diagnostic criteria.






Radiograph #28

image028 Is this a good radiograph, or is there something that could have been done to make it better?





Critique of Radiograph #28

image028
  • There are several good points to this radiograph:
    1. C3-T2 is adequately visualized, and the radiographic technique is adequate.
    2. The lateral margins of the image could be less collimated to show more of the soft tissue structures. This is especially important in the initial survey films of an unconscious patient.
  • Being intubated and in a cervical collar, the proper tube angle was achieved.





Radiograph #29

image029 Do you see any need for improvement of this radiograph?

If yes, then what should be done to improve it?





Critique of Radiograph #29

image029
  • Here is an example of the head being extended too far. This view resembles a reverse Waterís view for profiling the odontoid tip (Fuchs).
  • Also notice that the radiographic technique is inadequate. This low contrast image shows poor bone detail. In addition good patient positioning, subject detail must be adequate for soft tissues and bone detail.
    1. Repeat this image with the head tilted downward.
    2. Use a higher ratio grid, or select a technique that allows for an increase in the mAs, a doubling of the mAs is needed. Also a 15% reduction in kVp according to the 50/15 rule will help to improve subject contrast. Not using above 80 kVp initially will be less radiation to the patient than a repeated film.





Summary of the AP cervical spine view Critique

  • What has been learned:
    1. Vertebrae to be visualized are from T1 through C3.
    2. The lateral margins of the skin must be included on all AP cervical spine views.
    3. Adequate radiographic technique to evaluate for fractures, jumped facets, and alignment of the lateral margins of the vertebrae.
  • Apply your knowledge to each radiograph you take, asking did I meet the diagnostic criteria?




Diagnostic Criteria for Imaging the Open-mouth odontoid view of the Cervical Spine

  • A properly positioned open-mouth odontoid view will have the upper incisors superimposed over the base of the skull. This can be accomplished by placing the acanthiomeatal line perpendicular to the tabletop. Trauma requires that the patientís position not be changed to accommodate radiographic imaging. Two options are available for the technologist imaging trauma patients. 1) If the patient is conscious and able to open their mouth the tube (central ray) can be angled so that it passes through the acanthiomeatal line. Generally this requires the CR be angled 15-25 degrees caudal. If the patient is unconscious or is intubated the open-mouth odontoid view is considered unreliable. For these patients the radiologist should be consulted and a CT scan of the entire cervical spine is recommended. A limited CT scan from the occiput through C3 is also an acceptable alternative to the open-mouth view. At no time should the head be tilted or rotated during trauma imaging. Remember we always maintain spine support and a high suspicion for injury until proven otherwise.
  • Align the mid-sagittal plane (MSP) perpendicular to the horizontally directed central ray (CR). Moving the patient is permitted for ambulatory patients and those patients clinically cleared for motility. The trauma patient who is on spine precautions should not be manipulated to align the MSP. Instead, move the spine board while providing spine support to align the MSP. The part is positioned for non-trauma patients by having them raise or tuck their chin to achieve alignment. Again, if the patient is in a cervical collar the CR is angled so that it is parallel with the infraorbitomeatal line (IOML).
  • The lateral margins of C1/C2 should be aligned unless there is pathological reason for its misalignment. The spinous process of the axis should be on the mid-sagittal line. The spacing of the atlantoaxial joints should be equal. Equal spacing on the lateral borders of the odontoid process and the tip should not be superimposed on other structures. The space from the mandibular condyle to the lateral margin of C2 should be nearly equal on both sides.
  • Structures demonstrated are: atlantoaxial joints, occipitoatlantal joints, odontoid process and body of the axis, and lateral masses and transverse processes of the atlas and axis.
  • In addition to adequately visualizing C1 and C2, the following alignments should be meet when positioning the patient:
    1. The lateral margins of C1/C2 should be aligned unless there is pathological reason for its misalignment.
    2. The spinous process of the axis should be on the mid-sagittal line.
    3. The spacing of the atlantoaxial joints should be equal.
    4. Distance from the condyle to the lateral margin of the axis should be near equal on both sides. The space along the lateral borders of the odontoid process should be near equal and a space between the dens and anterior arch should be present.





Radiograph #30

image030 Identify the diagnostic criteria for imaging the open-mouth odontoid view using this radiograph?





Critique of Radiograph #30

image030a
  • In addition to adequately visualizing C1 and C2, the following alignments should be meet when positioning the patient:
    1. The lateral margins of C1/C2 should be aligned unless there is pathological reason for its misalignment.
    2. The spinous process of the axis should be on the mid-sagittal line.
    3. The spacing of the atlantoaxial joints should be equal.
    4. Equal spacing on the lateral borders of the odontoid process; the tip should be completely seen.





Radiograph #31

image031 This is obviously not the best quality for an open mouth odontoid view. What do you think could be done to make this a better radiograph?





Critique of Radiograph #31

image031

    This radiograph demonstrates a frequent positioning error seen with the open mouth odontoid view. The upper incisors are projected above the base of the skull. The spacing of the atlantoaxial joints is not demonstrated. To correct this positioning the patientís chin should be tucked down to align the teeth and base of the skull. The head should not be moved if the patient has acute trauma, instead, the CR is angled caudal 15-25 degrees. In either method the alignment of the acanthiomeatal line should be perpendicular to the tabletop by positioning the patient or through tube angulation. Notice the distance from the atlasís lateral masses to the mandibular rami is not equidistant. The spinous process of the axis is shifted from the midline indicating the part is rotated to the left. This radiograph is poorly collimated. There is nothing to be gained by including the maxillary sinuses on the open mouth odontoid view!






Radiograph #32

image032 Some technologists would consider this a good radiograph and send it for interpretation. What do you think should be done and why?





Critique of Radiograph #32

image032a

    Donít be fooled into thinking that this is a good radiograph just because the anatomy is present. The anatomical relationships must be presented as well. Here is another example of an open mouth odontoid view in which the head is extended too far back. The chin should be brought down until the upper teeth are superimposed over the base of the skull (arrows). This will require bringing the acanthiomeatal line perpendicular to the tabletop. The spacing of the atlantoaxial joints is not properly demonstrated. It is very possible to get a good view that demonstrates the joint spaces and odontoid process. Unfortunately, this view should be repeated.






Radiograph #33

image033 How would you adjust this patient to clear the odontoid process?





Critique of Radiograph #33

image033

    Because of the metal tooth plate it will be difficult to demonstrate the odontoid tip. The alignment of the teeth and base of the skull has been achieved so repeating this view may not yield the desired result. Try bringing the chin down just a little, then lower the tube to about 20 cm. Allow the divergence of the CR to clear the part. If you can demonstrate the anatomy having the complete diagnostic criteria with the exception of the superior third of the odontoid process you can just add a Fuchs view.






Radiograph #34

image034 Does this radiograph meet your standards for a good open-mouth odontoid view?

Should it be repeated, why or why not?





Critique of Radiograph #34

image034
  • Yes! The image should be repeated!
  • Consider that the lateral masses are covered by dental fillings; your positioning becomes even more critical.
  • The chin is tucked down too much! Slightly tilt the head backwards. This will help to demonstrate more of each lateral mass and the odontoid tip. You still may need to add a Fuchs view to demonstrate the spacing on each side of the odontoid peg.





Radiograph #35

image035 Can this radiograph be improved?





Critique of Radiograph #35

image035
  • Yes! The part is not well centered, and with better collimation it would have been an A+ radiograph.
  • Good points include proper spacing on either side of the odontoid peg, open atlantoaxial joints, and most of C1/C2.
  • Image should not be repeated (ALARA).





Radiograph #36

image036 Do you think this radiograph meets the diagnostic criteria for the open-mouth odontoid view, or would you repeat it?





Critique of Radiograph #36

image036a

    The line at the arrow is a Mach band phenomenon, not a fracture. The posterior arch of C1 and base of the skull are projected onto the odontoid process. If the upper teeth are brought downward by flexing the chin this will help in better demonstrating the tip of the odontoid process. In addition, it may be necessary to do a Fuchs view to demonstrate the upper third of the odontoid process. Decreasing the SID and bringing the chin slightly downward may help.






Radiograph #37

image037 How should this anatomy be demonstrated based on the clinical picture this radiograph has recorded?





Critique of Radiograph #37

image037
  • This is an attempt to image an open-mouth odontoid view of an unconscious intubated patient.
  • This type of imaging accounts for up to 16% missed diagnosis simply because there is ventilation motion, obstruction by endotracheal tube, and poor positioning of the patient. Donít try heroic measures to get this odontoid view; it is considered an unreliable image.
  • Current ACR standards recommend a CT scan when the patient is unconscious, intubated having suspected cervical spine injury.





Radiograph #38

image038 This is really bad positioning! No technologist should shoot an image like this one or pass it for interpretation. How would you correct the positioning seen on this radiograph?





Critique of Radiograph #38

image038

    The head is obviously extended back too far. Bring the head down as in flexion so that the upper incisors are in line with the base of the skull. The acanthiomeatal line should be perpendicular to the tabletop. If the patient is uncooperative, place a sponge or towel under the head to achieve desired flexion. If this were a trauma patient in a cervical collar then the CR should be angled at least 20-25 degrees caudal. This will open the atlantoaxial joints as well.






Radiograph #39

image039 Does this image meet the diagnostic criteria for imaging the open-mouth odontoid view? Consider that this patient is intubated, what should be done to get a good look at the odontoid process, atlas, and axis?





Critique of Radiograph #39

image039

    This radiograph demonstrates how technologists have tried creative ways to image the atlas and axis of intubated patients. This is a shoot through AP of the axis. Such imaging techniques cannot meet the diagnostic criteria. It is easy to see why a 16% missed diagnosis is reported for plain film cervical spine imaging of intubated unconscious patients. ACR recommends thin slice CT imaging from the occiput through C3 of these patients.






Radiograph #40

image040 What do you see that is wrong with this radiograph; tell what can be done to improve it?





Critique of Radiograph #40

image040

    There is considerable obstruction of the odontoid peg so that the image cannot be considered diagnostic. The head should be tilted back slightly to improve the presentation of the odontoid process and spacing of the atlantoaxial joints. Aligning the acanthiomeatal line perpendicular to the tabletop will improve this presentation. This image should be kept for interpretation since it shows most of the axis, and all of C3.






Radiograph #41

image041 Would you consider this a good open mouth odontoid view; what improvements if any should be made in positioning this patient?





Critique of Radiograph #41

image041a
  • This is a good radiograph; however, a close inspection reveals that the head is rotated. The view does not need to be repeated, but you should strive to make your images free of lateral rotation.
  • Notice that the spinous process is off centered evidenced by uneven spacing along the left lateral margin of the odontoid peg (arrows).
  • If the spinous process had been aligned and the odontoid tip spacing as presented, then this would be a pathological finding.





Radiograph #42

image042
Discuss this radiograph and tell if it is a useful way of imaging today?





Critique of Radiograph #42

image042a
  • This is an orthopantomogram (panorex) view.
  • This is not a common way of imaging the upper cervical spine; however, in trauma centers where they may have the supine version of the panorex machine, it is an alternative. In some of the pictures we have seen dental fillings obscuring the odontoid tip. The panorex view projects the mandible lateral to the spine so that the teeth do not obstruct it.
  • The relationship of the axis to the condyles of the skull (arrows) and to the axis is well demonstrated.
  • This view is almost completely replaced by CT scanning of the cervical spine.
  • Although the entire atlas is demonstrated, more of the base of the skull should have been imaged on this panorex scan.





Radiograph #43

image043 How would you correct this badly positioned radiograph?





Critique of Radiograph #43

image043a
  • Since the base of the skull (white arrow) is below the upper incisors (yellow arrow), the head should be tilted downward. Do this and center the part to the film. Tighter collimation should also be applied in keeping with ALARA.
  • It is a good picture in that the relationship of the condyles of the skull and the atlas is seen (pink arrows). This relationship should be well demonstrated on a properly made open-mouth odontoid view.





Radiograph #44

image044 What should be done to correct the positioning of this patient?





Critique of Radiograph #44

image044

    The upper incisors are below the base of the skull obscuring the spacing of the atlantoaxial joints and odontoid process. The head should be extended upward to correct the positioning. This film should be kept as well as the repeated film since C3 is effectively visualized.






Radiograph #45

image045 What should be done to correct the positioning of this patient?





Critique of Radiograph #45

image045a
  • The upper incisors are projected above the base of the skull.
  • Again we see that the base of the skull obscures the odontoid process (white arrow).
  • The head should be tilted down to correct for this positioning.





Radiograph #46

image046 What do you see in this radiograph that warrants repeating it, or would you be satisfied with this image?





Critique of Radiograph #46

image046a

    What should get your attention is the pseudofracture (Mach band phenomenon) through the dens. The lucency across the dens (arrows) is due to the overlap of the posterior arch of C1. Notice it continues on the right lateral edge of the odontoid process. The image should be repeated to remove the lucency from the odontoid process. The chin should be brought down slightly and the mouth opened wider.






Summary of the open-mouth odontoid view Critique

  • What has been learned:
    1. Vertebrae to be visualized are C1 and C2.
    2. The odontoid tip must be demonstrated with near equal spacing on either side of the peg.
    3. The atlantoaxial joints should be opened allowing for evaluating the joint space.
    4. The spinous process of the axis should be midline.
    5. The lateral margins of the each lateral mass articulation with the superior articular processes of C2 must be seen.
    6. Adequate radiographic technique to evaluate for fracture.
  • Apply your knowledge to each radiograph you take, asking did I meet the diagnostic criteria?



Copyright image Copyright 2006 Nicholas Joseph Jr.








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