Skull Projections Techniques
144 Questions
2 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the proper position for the Modified Waters projection?

  • Supine with MSP & MML perpendicular to the IR
  • Prone with MSP parallel to the IR
  • Sitting with OML 37 degrees to IR
  • Prone with MSP & MML perpendicular to the IR (correct)

    • In the Sweet Method, which structure is primarily targeted during the imaging process?

  • Facial bones (correct)
  • Lateral skull
  • Chest cavity
  • Cervical spine

    • What is the required angulation of the OML in the Reverse Waters method?

  • 50 degrees
  • 30 degrees
  • 45 degrees
  • 37 degrees (correct)

    • Which projection utilizes a perpendicular CR directed to the Acanthion?

    <p>Modified Waters Projection</p> Signup and view all the answers

    What is the key characteristic of the Towne View Method in terms of positioning?

    <p>MSP perpendicular to the IR and OML 30 degrees to the IR</p> Signup and view all the answers

    What is the appropriate central ray (CR) angle for the Towne method?

    <p>30 degrees cephalad</p> Signup and view all the answers

    What is the central ray (CR) orientation for the Schuller/Pfeiffer Method?

    <p>30° caudad</p> Signup and view all the answers

    In the Axiolateral Oblique Projection, how should the patient's head be oriented?

    <p>In true lateral position</p> Signup and view all the answers

    Which anatomical structure is best demonstrated with the Schuller Method?

    <p>Sella turcica</p> Signup and view all the answers

    Which projection provides a panoramic image of the mandible and TMJ?

    <p>Panoramic Tomography</p> Signup and view all the answers

    What is the recommended patient position for the Submentovertex Projection?

    <p>Supine or seated upright with IOML parallel to IR</p> Signup and view all the answers

    In the Lysholm Method, what is the recommended patient position?

    <p>Semiprone, with the MSP parallel to IR</p> Signup and view all the answers

    For the Valdini Method, what is the orientation of the central ray?

    <p>50° to OML with the CR entering at the nasion</p> Signup and view all the answers

    Which of the following describes the purpose of the Caldwell Projection?

    <p>To assess the nasal sinuses and frontal bone</p> Signup and view all the answers

    What angle is recommended when positioning for the Axiolateral Oblique Projection toward the ramus?

    <p>25 degrees cephalad</p> Signup and view all the answers

    Which sinuses are primarily illustrated in the Schuller Method?

    <p>Sphenoidal and maxillary sinuses</p> Signup and view all the answers

    Which adjustment is recommended for muscular or hypersthenic patients during lateral projections?

    <p>Angle CR 10 degrees cephalad</p> Signup and view all the answers

    What central ray positioning is used for the Towne View Method?

    <p>30° caudad</p> Signup and view all the answers

    In the Verticosubmental Projection, how should the patient's chin be positioned?

    <p>Fully hyperextended</p> Signup and view all the answers

    What should be the position of the patient's IOML in the Lysholm Method?

    <p>Parallel to the transverse axis of IR</p> Signup and view all the answers

    In a submentovertex projection, what is the relationship of the MSP to the IR?

    <p>Perpendicular to the IR</p> Signup and view all the answers

    What is the significance of filling the mouth with air during the Modified Towne Method?

    <p>Enhances contrast around the TMJs</p> Signup and view all the answers

    Which of the following is NOT a structure visualized by the Valdini Method?

    <p>Ethmoid sinus</p> Signup and view all the answers

    In the closed-mouth position during the Towne Method, which teeth need to be in contact?

    <p>Posterior teeth</p> Signup and view all the answers

    What is an essential feature of the Caldwell Projection?

    <p>CR is directed 15° caudad</p> Signup and view all the answers

    What is the correct angulation of the central ray (CR) when using the Haas Method?

    <p>30 degrees caudad</p> Signup and view all the answers

    What anatomical structures are primarily visualized in the projection obtained with the Orbitoparietal Oblique?

    <p>Inferior and lateral margin of the uppermost orbit</p> Signup and view all the answers

    In which position should the patient be placed for the PA Axial Projection?

    <p>Prone with forehead and nose against the table</p> Signup and view all the answers

    When performing the projection above the glabella, which orientation of the AML is mandated?

    <p>Perpendicular to the IR</p> Signup and view all the answers

    What is the Recommended Positioning (RP) for the entrance of the central ray in the Haas Method?

    <p>1.5 inches below the inion</p> Signup and view all the answers

    What is the main advantage of using the Sweet Method in imaging?

    <p>It determines the exact location of a foreign body using geometric calculations.</p> Signup and view all the answers

    Which projection best demonstrates the zygomatic bone and anterior wall of the maxillary sinus?

    <p>Modified Waters Projection</p> Signup and view all the answers

    In the Reverse Waters Method, what is the primary angle of OML to the IR?

    <p>37 degrees</p> Signup and view all the answers

    What is the purpose of positioning the petrous ridges below the inferior border of orbits during imaging?

    <p>To eliminate distortion in the facial bone images.</p> Signup and view all the answers

    Which apparatus is essential for the Sweet Method?

    <p>Localizing device and film pedestal</p> Signup and view all the answers

    Which anatomical structures are primarily demonstrated in the Caldwell Projection?

    <p>Orbital rims, maxillae, nasal septum, zygomatic bones &amp; anterior nasal spine</p> Signup and view all the answers

    What is the central ray (CR) angle used in the Exaggerated Caldwell method?

    <p>30 degrees caudad</p> Signup and view all the answers

    In the Waters Method, what is the proper orientation of the OML with respect to the IR?

    <p>At a 37-degree angle to IR</p> Signup and view all the answers

    Which projection is utilized specifically for demonstrating medial or lateral displacement of fragments in fractures?

    <p>Law Method</p> Signup and view all the answers

    What position is required for the patient during the Law Method PA Oblique Axial Projection?

    <p>Semiprone with the affected side against the IR</p> Signup and view all the answers

    For the Tangential Projection, which structure is specifically targeted?

    <p>Zygomatic arch</p> Signup and view all the answers

    What is the patient positioning for the Reverse Waters method?

    <p>Supine with head elevated and MSP perpendicular to sponge</p> Signup and view all the answers

    Which of the following describes the positioning of the head during the Initial positioning for the Waters Method?

    <p>Forehead and nose against IR</p> Signup and view all the answers

    What is the appropriate direction of the central ray (CR) for the Axiolateral Projection?

    <p>25-30 degrees caudad</p> Signup and view all the answers

    In the closed-mouth position, where does the condyle lie during the Axiolateral Projection?

    <p>In the mandibular fossa</p> Signup and view all the answers

    Which method requires the patient's head to be in a true lateral position for the TMJ examination?

    <p>Zanelli Method</p> Signup and view all the answers

    What is the proper rotation of the MSP for the Schuller Method?

    <p>15 degrees toward the IR</p> Signup and view all the answers

    For the lateral transfacial position, what is the orientation of the patient's chin?

    <p>30 degrees to the IR</p> Signup and view all the answers

    What structure is best demonstrated using the Schuller Method?

    <p>Mandibular condyles</p> Signup and view all the answers

    In the opened-mouth position during the Axiolateral Projection, where do the condyles lie?

    <p>Inferior to the articular tubercle</p> Signup and view all the answers

    What is the recommended patient position for the Axiolateral Oblique projection?

    <p>Semiprone with MSP rotated 15 degrees</p> Signup and view all the answers

    Which of these structures is best visualized using the Schuller Method?

    <p>Mastoid antrum</p> Signup and view all the answers

    What is the appropriate central ray angulation for the Haas Method?

    <p>25° cephalad</p> Signup and view all the answers

    In the Towne Method, what is the central ray reference point?

    <p>Inion</p> Signup and view all the answers

    Which positioning is recommended for the Axiolateral positions?

    <p>Semiprone, with head in true lateral</p> Signup and view all the answers

    What anatomical structures does the Valdini Method primarily illustrate?

    <p>Internal auditory meatus and labyrinths</p> Signup and view all the answers

    In the Henschen Method, what structure is primarily targeted?

    <p>Petrous portion</p> Signup and view all the answers

    What is a key factor in positioning for the Runstrom Recommendation?

    <p>Open mouth during exposure</p> Signup and view all the answers

    What is the positioning requirement for the Modified Towne Method?

    <p>Supine, OML/IOML &amp; MSP perpendicular to IR</p> Signup and view all the answers

    Which projection uses a 30° caudad central ray angulation?

    <p>Towne Method</p> Signup and view all the answers

    For which projection would a patient ideally be in a recumbent position?

    <p>Valdini Method</p> Signup and view all the answers

    In the submentovertex projection, what alignment is essential for the MSP?

    <p>MSP perpendicular to IR</p> Signup and view all the answers

    Which of the following is NOT a structure that can be visualized using the Schuller Method?

    <p>Mandibular fossa</p> Signup and view all the answers

    What is the proper head position for imaging using the Henschen Method?

    <p>Head in true lateral position</p> Signup and view all the answers

    Which angulation is specific for the Lysholm/Runstrom II Method?

    <p>35° caudad</p> Signup and view all the answers

    What planes are required to be perpendicular in the Modified Waters method?

    <p>MSP and MML</p> Signup and view all the answers

    Which projection is best utilized to visualize the facial bones with less axial angulation?

    <p>Modified Waters Method</p> Signup and view all the answers

    In the Sweet Method, what does the apparatus specifically include?

    <p>Sweet localizing device</p> Signup and view all the answers

    Which structure is best demonstrated in the Modified Waters projection?

    <p>Maxillary sinus</p> Signup and view all the answers

    What is the primary purpose of the Sweet Method in imaging?

    <p>To localize foreign bodies</p> Signup and view all the answers

    What is the central ray angle for the Caldwell Method when using an exaggerated angulation?

    <p>30 degrees caudad</p> Signup and view all the answers

    In the Waters Method, what is the required angle of the OML relative to the IR?

    <p>37 degrees</p> Signup and view all the answers

    Which projection is described as providing visualization of the nasal bones with minimal superimposition?

    <p>Law Method</p> Signup and view all the answers

    What is the positioning recommendation for the patient's chin during the Tangential Projection?

    <p>Chin fully extended</p> Signup and view all the answers

    What should be the orientation of the patient's head for the PA Axial Projection?

    <p>Nose against the IR</p> Signup and view all the answers

    Which method requires the patient to be in a prone position with MSP and MML perpendicular to the IR?

    <p>Waters Method</p> Signup and view all the answers

    What anatomical structures does the Caldwell Projection primarily visualize?

    <p>Orbital rims and nasal septum</p> Signup and view all the answers

    What is the disadvantage of using the PA Axial Projection for patients?

    <p>Inability to position patients with short nasal bones</p> Signup and view all the answers

    What is the required central ray (CR) angulation for the Axiolateral Projection?

    <p>25-30 degrees caudad</p> Signup and view all the answers

    In the opened-mouth position during the Axiolateral Projection, where do the condyles lie?

    <p>Inferior to the articular tubercle</p> Signup and view all the answers

    What is the correct positioning for the axiolateral projection using the double angulation method?

    <p>Head in true lateral position</p> Signup and view all the answers

    What is the recommended position of the head for the Zaneli Method?

    <p>Semiprone with MSP rotated 30 degrees</p> Signup and view all the answers

    What is the central ray (CR) angle used in the Towne method for the OML?

    <p>30 degrees caudad</p> Signup and view all the answers

    In the Schuller Method, how should the patient's head be oriented relative to the IR?

    <p>MSP rotated 15 degrees towards the IR</p> Signup and view all the answers

    Which structures are better demonstrated when the central ray is perpendicular to the occlusal plane?

    <p>Mandibular condyles and fossae</p> Signup and view all the answers

    In the PA tangential position, how should the patient's face be oriented?

    <p>Cheek against the IR and rotated away from side of interest</p> Signup and view all the answers

    What aspect is evaluated by performing a lateral projection of the sinuses?

    <p>Presence or absence of fluid</p> Signup and view all the answers

    What is the recommended patient position for the single angulation method?

    <p>Prone with tape auricle forward</p> Signup and view all the answers

    What structure should be seen free of superimposition in the axiolateral position?

    <p>Mastoid process</p> Signup and view all the answers

    Which method involves a patient position of true lateral with the chin elevated?

    <p>Lateral Transfacial Position</p> Signup and view all the answers

    For a Schuller projection, where is the reference point (RP) for the entrance of the central ray situated?

    <p>0.5 inches anterior and 2 inches superior to the upside EAM</p> Signup and view all the answers

    What is the primary purpose of the part angulation method?

    <p>To ensure proper angling of the CR</p> Signup and view all the answers

    For the Law method, what is the central ray (CR) angle when targeting the TMJ?

    <p>15 degrees caudad</p> Signup and view all the answers

    In the Towne method, if the IOML is perpendicular to the IR, what is the required central ray (CR) angle?

    <p>37 degrees caudad</p> Signup and view all the answers

    What is the required position for the Law Method?

    <p>Seated-erect with chin against the IR</p> Signup and view all the answers

    Which structures are primarily visualized in the RHESE Method?

    <p>Posterior &amp; anterior ethmoidal sinuses and sigmoid sinus</p> Signup and view all the answers

    What is the central ray (CR) angle used for the Modified Hickey Method?

    <p>25-30 degrees cephalad</p> Signup and view all the answers

    In the positioning for the Law Method, what is the relationship of the neck to the imaging receptor?

    <p>Fully extended</p> Signup and view all the answers

    Which anatomical structure is not typically included in the images obtained using the RHESE Method?

    <p>Frontal bone structure</p> Signup and view all the answers

    What is the positioning of the patient’s head in the Modified Hickey Method during the AP Tangential position?

    <p>Rotated toward the side of interest</p> Signup and view all the answers

    What is the orientation of the IOML during the Modified Hickey Method?

    <p>Parallel to the IR</p> Signup and view all the answers

    Which projection utilizes a central ray angled 25-30 degrees cephalad from the uppermost gonion?

    <p>Law Method</p> Signup and view all the answers

    What is the recommended patient position for the PA projection of the skull?

    <p>Prone with forehead and nose against the image receptor</p> Signup and view all the answers

    Which line is described as being 7 degrees off between the OML and IOML?

    <p>Infraorbitomeatal line (IOML)</p> Signup and view all the answers

    Which reference point is used for the AP projection of the skull?

    <p>Nasion</p> Signup and view all the answers

    What characteristic defines the successful PA projection of the skull with regards to the petrous pyramids?

    <p>Petrous pyramids completely filling the orbits</p> Signup and view all the answers

    How does the Interpupillary line (IPL) relate to other skull planes during imaging?

    <p>It is parallel to the OML during the lateral view</p> Signup and view all the answers

    What is the maximum angle of the OML to the IR during the Parietoacanthial projection?

    <p>37 degrees</p> Signup and view all the answers

    Which sinuses are best demonstrated using the Schuller method?

    <p>Sphenoidal and ethmoidal sinuses</p> Signup and view all the answers

    In the Open-Mouth Waters Method, what should the patient be instructed to do during the exposure?

    <p>Phonate 'ah'</p> Signup and view all the answers

    What is the required central ray (CR) orientation for the Axial Transoral Position?

    <p>Perpendicular to IOML</p> Signup and view all the answers

    During the Verticosubmental projection, what is the patient's position with respect to the IR?

    <p>Seated upright with neck hyperextended</p> Signup and view all the answers

    What is the central ray (CR) orientation when using the Stenvens Method?

    <p>35° caudad</p> Signup and view all the answers

    In the Hirtz Method, where is the required projection point (RP) located?

    <p>Midway between and 1 in. anterior to the EAMs</p> Signup and view all the answers

    Which projection positions the patient's forehead, nose, and zygoma against the image receptor?

    <p>Posterior Profile Position</p> Signup and view all the answers

    What is the angulation of the IOML in the Axiolateral Oblique Projection?

    <p>Parallel to the IR</p> Signup and view all the answers

    Which structures are visualized in the Axiolateral Oblique Projection?

    <p>Petrous ridges and mastoid air cells</p> Signup and view all the answers

    What patient position is required for the Mayer Method?

    <p>Supine with auricles taped forward</p> Signup and view all the answers

    What is the direction of the central ray (CR) in the Reverse Stenvens Method?

    <p>45° caudad</p> Signup and view all the answers

    In the Stenvens Method, what structures are best visualized?

    <p>Petrosae and tympanic cavities</p> Signup and view all the answers

    What type of fracture involves the floor of the orbit?

    <p>Blowout Fx</p> Signup and view all the answers

    Which fracture is characterized by a jagged and irregular shape?

    <p>Linear Fx</p> Signup and view all the answers

    What is the general description of a Le Fort fracture?

    <p>Bilateral horizontal fractures of the maxillae</p> Signup and view all the answers

    Which type of fracture is caused by trauma to one side, affecting the opposite side of the structure?

    <p>Contre-Coup Fx</p> Signup and view all the answers

    What anatomical structure is primarily involved in a Tripod fracture?

    <p>Zygomatic arch</p> Signup and view all the answers

    In a depressed fracture, what is the primary outcome?

    <p>A portion of the skull is depressed into the cranial cavity</p> Signup and view all the answers

    What condition involves inflammation of the mastoid air cells?

    <p>Mastoiditis</p> Signup and view all the answers

    What is the central ray angle for a True Caldwell projection?

    <p>23° caudad</p> Signup and view all the answers

    In the context of skull fractures, what does the term 'Paget’s Disease' refer to?

    <p>Condition marked by thick, soft bone with bowing fractures</p> Signup and view all the answers

    Which projection is used to visualize the anterior and side walls of the cranium?

    <p>Modified Caldwell Method</p> Signup and view all the answers

    What is the central ray angle required for the Modified Lysholm method?

    <p>30 degrees caudad</p> Signup and view all the answers

    Which structure is primarily visualized using the Hough method for the parieto-orbital oblique projection?

    <p>Optic canal/foramen</p> Signup and view all the answers

    During a PA axial projection using the Caldwell method, which angle does the CR make with OML?

    <p>20-25 degrees</p> Signup and view all the answers

    In the Water method, what is the angle relationship of the OML to the IR?

    <p>37 degrees</p> Signup and view all the answers

    What position should the patient's chin be in during the Modified Waters method?

    <p>Against the IR</p> Signup and view all the answers

    What is the RP for the central ray entrance point in the Pfeiffer-Comberg method?

    <p>Midpoint of the orbits</p> Signup and view all the answers

    Which foreign body localization technique uses a lateral projection for imaging?

    <p>Vogt-Bone-Free Position</p> Signup and view all the answers

    What is the required angle for the CR in the PA axial projection for the Bertel method?

    <p>20-25 degrees</p> Signup and view all the answers

    Which projection demonstrates the petrous pyramids lying below the orbital shadows?

    <p>Caldwell Method</p> Signup and view all the answers

    What angle should the IOML be positioned for the Hough method?

    <p>Perpendicular to IR</p> Signup and view all the answers

    During the Alexander method, what is the angulation of the central ray?

    <p>25 degrees cephalad</p> Signup and view all the answers

    Which projection is indicated for imaging of the inferior orbital fissures?

    <p>Hough Method</p> Signup and view all the answers

    What is the positioning of the patient's head in the Vogt-Bone-Free position for lateral exposure?

    <p>Facing directly ahead</p> Signup and view all the answers

    In the Modified Waters method, what instruction should be given to the patient during imaging?

    <p>Close your eyes</p> Signup and view all the answers

    Study Notes

    Skull Projections

    • Schuller/Pfeiffer Method
      • Submentovertical Projection (SMV)
        • Patient Position: Supine or seated-upright, IOML parallel to IR, MSP perpendicular to IR, head resting on vertex, neck hyperextended
        • Central Ray (CR): Perpendicular to IOML, MSP of throat between gonion (entrance)
        • Structures Demonstrated: Foramen ovale & spinosum, symmetric petrosae, mastoid processes, carotid canals, sphenoidal & ethmoidal sinuses, mandible, bony nasal septum, dens of axis, occipital bone, maxillary sinus superimposed over the mandible, zygomatic arches, axial tomography of orbits, optic canals, ethmoid bone, maxillary sinuses & mastoid processes
      • Verticosubmental Projection
        • Patient Position: Prone, chin fully hyperextended, MSP perpendicular to IR
        • Central Ray (CR): Perpendicular to IOML
        • Structures Demonstrated: Zygomatic arches free of superimposition
    • Modified Towne Method (AP Axial Projection - Jug Handle View)
      • Patient Position: Supine, OML/IOML & MSP perpendicular to IR
      • Central Ray (CR): 30 degrees caudad (OML ┴); 37 degrees caudad (IOML ┴)
    • Lysholm Method (Axiolateral Method)
      • Patient Position: Semiprone, MSP parallel to IR, IOML parallel to transverse axis of IR, IPL perpendicular to IR
      • Central Ray (CR): 30-35 degrees caudad
      • Structures Demonstrated: Oblique position of lateral aspect of cranial base closest to IR
    • Valdini Method (PA Axial Projection)
      • Patient Position: Recumbent or seated-erect, upper frontal region of skull against IR, MSP perpendicular to IR, head acutely flexed, IOML 50 degrees/OML 50 degrees, line extending from inion to 0.5 cm distal to nasion form 28 degrees to CR
      • Central Ray (CR): Perpendicular, inion (entrance), 0.5 cm distal to nasion (exit)
      • Structures Demonstrated: Dorsum sellae, Internal Auditory Meatus (IAM), Labyrinth, External auditory meatus, Tymphanic cavity, Bony part of Eustachian tube, Dorsum sellae & posterior clinoid processes within or above shadow of foramen magnum, Tubeculum sellae, anterior clinoid processes
    • PA Axial Projection
      • Patient Position: Prone, nose & chin against IR, AML & MSP perpendicular to IR, fill the mouth with air
      • Central Ray (CR): 30 degrees cephalad
      • Structures Demonstrated: Mandibular body, TMJs, condylar processes
    • Axiolateral Oblique Projection
      • Patient Position: Seated/semiprone/semisupine, head in true lateral & IPL perpendicular to IR (ramus), head rotated 30 degrees toward IR (body), head rotated 45 degrees toward IR (symphysis), head rotated 10-15 degrees toward IR (general survey), mouth closed, neck extended
      • Central Ray (CR): 25 degrees cephalad
      • Structures Demonstrated: Mandibular body & TMJs
    • Panoramic Tomography/Pantomography/Rotational Tomography
      • Technique employed to produced tomograms of curved surfaces
      • Structures Demonstrated: Panoramic image of the entire mandible, TMJ, dental arches, distortion-free lateral image of the entire mandible, patients who sustained severe mandibular or TMJ trauma, general survey studies of dental abnormalities, adjuvant for pre-bone marrow transplant

    Temporomandibular Joints (TMJ)

    • Schuller/Pfeiffer Method
      • Submentovertical Projection (SMV)
        • Patient Position: Supine or seated-upright, IOML parallel to IR, MSP perpendicular to IR, head resting on vertex, neck hyperextended
        • Central Ray (CR): Perpendicular to IOML
        • Structures Demonstrated: Mandibular body, coronoid & condyloid processes of rami
      • Verticosubmental Projection
        • Patient Position: Prone, chin fully hyperextended, IR against throat, MSP perpendicular to IR
        • Central Ray (CR): Perpendicular to IOML
    • Towne Method (AP Axial Projection)
      • Patient Position: Supine, MSP & OML perpendicular to IR
      • Closed-mouth Position: Posterior teeth in contact, not incisors. Rationale: prevents mandibular protrusion & condyles to be carried out of mandibular fossae
      • Opened-mouth Position: Open as wide as possible, Mandible not protruded (jutted forward), Not perform in trauma patients
      • Central Ray (CR): Perpendicular
      • Structures Demonstrated: Orbits, maxillae & zygomatic arches, Petrous ridges below the maxillae, Blow out fractures

    Nasal Bone

    • Lateral Projection
      • Patient Position: Semiprone, MSP & IOML parallel to IR, IPL perpendicular to IR
      • Central Ray (CR): Perpendicular

    Additional Information

    • Sweet Method
      • Used to determine the exact location of a foreign body using geometric calculations
      • Uses a Sweet localizing device and a Sweet film pedestal
      • Requires 1 projection: Lateral with 2 exposures
    • Reverse Waters Method (AP Axial Projection)
      • Patient Position: Supine, MSP & MML perpendicular to IR, OML 37 degrees to IR, chin up
      • Central Ray (CR): Perpendicular
      • Structures Demonstrated: Zygomatic bone, anterior wall of maxillary sinus of side up
    • Modified Waters
      • Patient Position: Prone, MSP & MML perpendicular to IR, OML 55 degrees to IR
      • Central Ray (CR): Perpendicular
      • Structures Demonstrated: Zygomatic bone, anterior wall of maxillary sinus of side up

    Cranial Facial Projections

    • Distal to Nasion
      • Caldwell Method
        • PA Axial Projection
          • Position: Prone; forehead & nose against IR; OML perpendicular to IR
          • RP: Nasion
          • CR: 15º caudad or 30º caudad (Exaggerated Caldwell)
          • SS: Orbital rims, maxillae, nasal septum, zygomatic bones & anterior nasal spine
            • Petrous ridges at lower third of orbits (15º caudad)
            • Petrous ridges below the inferior orbital margins (30º caudad)
            • Orbital floors (30º caudad)
      • Waters Method
        • Pariéto-Acānthial Projection
          • Position: Prone; MSP & MML perpendicular to IR; OML 37º to IR; nose ¾ in.above glabella
          • RP: Acanthion (exit)
          • CR: Perpendicular
          • SS: Nasal bones with minimal superimposition
          • ER: Demonstration of any medial or lateral displacement of fragments in fractures

    Skull Projections

    • Sinus Projections
      • Lateral Projection
        • Position: Semiprone; MSP & IOML parallel to IR; IPL perpendicular to IR
        • RP: ¾ in. (old) or ½ in. above nasion
        • CR: 35° caudad
        • SS: Condyles & neck of condylar processes
          • Closed mouth: condyle lying in mandibular fossa
          • Opened mouth: condyles lying inferior to articular tubercle
      • Henschen, Schuller, & Lysholm Methods
        • Axiolateral Positions
          • Position: Semiprone; head in true lateral; MSP parallel to IR; IPL perpendicular to IR; IOML parallel to transverse axis of IR; auricles taped forward
          • RP: Dependent EAM closest to IR
          • CR: 15º caudad (Henschen/Cushing); 25º caudad (Schuller); 35º caudad (Lysholm/Runstrom II)
          • SS: Mastoid & petrous portion
            • Mastoid cells, mastoid antrum, IAM & EAM & tegmen tympani (Henschen)
            • Tumors of acoustic nerve (Cushing)
            • Pneumatic structures of mastoid process, mastoid antrum, tegmen tympani, IAM & EAM, sinus & dural plates & mastoid emissary when present (Schuller)
            • Mastoid cells, matoid antrum, IAM & EAM, tegmen tympani, labyrinthine area & carotid canal (Lysholm/Runstrom II)
      • Towne Method
        • AP Axial Projection
          • Position: Supine; OML/IOML & MSP perpendicular to IR
          • RP: MSP b/n EAMs
          • CR: 30º caudad (OML ┴); 37º caudad (IOML ┴)
          • SS: Petrosae above base of the skull
            • IAM
            • Arcuate eminences
      • Schuller/Pfeiffer Method
        • Submentovertical (Subbasal) Projection
          • Position: Supine or Seated-upright (more comfortable); OML parallel to IR or CR perpendicular to OML (cannot fully extend the neck) or supraorbitomeatal line (SOML) parallel to IR; MSP perpendicular to IR; head rested on vertex; neck hyperextended
          • RP: ¾ in.

    Other Projections

    • Law Method
      • PA Oblique Axial Projection
        • Position: Semiprone; zygoma, nose & chin against IR; unaffected side against IR; OML perpendicular to IR; Center IR 2 in.above floor of maxillary sinuses
        • CR: 30º caudad (OML ┴); 37º caudad (IOML ┴)
        • SS: Sellar region
          • Dorsum sellae, tuberculum sellae & anterior clinoid processes through occipital bone above shadow of foramen magnum (30º caudad)
          • Dorsum sellae & posterior clinoid processes w/in shadow of foramen magnum (37º caudad)
          • Symmetric petrous pyramid
    • Rhése Method
      • Orbitó-Pariétal Oblique Projection
        • Position: Supine; affected orbit away from IR; AML perpendicular to IR; MSP 53º angle to IR
        • RP: Inferior and lateral margin of uppermost orbit
        • CR: Perpendicular
        • SS: Orbits, maxillae & zygomatic arches
    • Sweet Method
      • Lateral Projection
        • Position: 2 exposures
        • SS: It determines the exact location of a foreign body by use of geometric calculations
    • Valdini Method
      • PA Axial Projection
        • Position: Recumbent or seated-erect (more comfortable); upper frontal region of skull against IR; MSP perpendicular to IR; head acutely flexed; IOML 50º/OML 50°; line extending from inion to 0.5 cm distal to nasion form 28º to CR
        • RP: 0.5 cm distal to nasion (dorsum sellae); foramen magnum at or slightly above level of EAM (petrosae)
        • CR: Perpendicular; inion (entrance); 0.5 cm distal to nasion (exit)
        • SS:
          • DILA: dorsum sellae; internal auditory meatus (IAM); labyrinth
          • ETB: external auditory meatus; tymphanic cavity; bony part of Eustachian tube
    • Modified Waters Method
      • Position: Prone; MSP & MML perpendicular to IR; OML 55º to IR
      • RP: Acanthion (exit)
      • CR: Perpendicular
      • SS: Facial bones w/ less axial angulation
        • Petrous ridges below the inferior border of orbits
        • Zygomatic bone
        • Anterior wall of maxillary sinus of side up
    • Haas Method
      • PA Axial Projection
        • Position: Prone; MSP & OML perpendicular to IR; forehead & nose against the table; IR center 1 in.to nasion
        • RP: Nasion
        • CR: 25º cephalad
        • SS: Symmetric axial frontal image of petrous portions projected above the base of the skull
          • IAM
          • Labyrinths
          • Mastoid antrums
          • Middle ears
          • Dorsum sellae & posterior clinoid processes w/in shadow of foramen magnum

    Distal to Nasion

    • Acanthion is the exit point for this projection.
    • Perpendicular central ray.
    • Superior facial bones are imaged similarly to the Waters projection, but the image is magnified.
    • Tangential projection.
    • Extraoral film requires a prone positioning, with chin resting on sandbags and theMSP perpendicular to the IR.
    • Intraoral film (Occlusal Film) requires a supine position with the head elevated. The MSP is perpendicular to the sponge and the GAL is parallel to the sponge and perpendicular to the film.
    • Glabelloalveolar line is the reference point.
    • Perpendicular central ray.
    • Nasal Bones are imaged with minimal superimposition.
    • Medial or lateral displacement of fragments in fractures can be visualized.
    • Contraindications:
      • Children or adults with short nasal bones.
      • Concave face or protruding upper teeth.

    Caldwell Method

    • PA Axial projection.
    • Prone positioning, with forehead and nose against the IR.
    • OML is perpendicular to the IR.
    • Nasion is the reference point.
    • 15° or 30° caudad angle for the central ray.
      • 15° caudad: Petrous ridges at the lower third of the orbits.
      • 30° caudad: Petrous ridges below the inferior orbital margins and orbital floors.

    Law Method

    • PA Oblique Axial.
    • Semiprone positioning with the zygoma, nose, and chin against the IR, the unaffected side against the IR, and the OML perpendicular to the IR.
    • Center the IR 2 inches above the floor of the maxillary sinuses.
    • Two exposures are required.

    Sweet Method

    • Determines the exact location of a foreign body using geometric calculations.
    • Apparatus:
      • Sweet Localizing Device
      • Sweet film pedestal
    • One projection:
      • Lateral: Two exposures

    Waters (Parieto-Acanthial Projection)

    • Prone positioning with the MSP and MML perpendicular to the IR.
    • OML is 37° to the IR and the nose is 3/4 inch (1.9 cm) from the IR.
    • Acanthion is the exit point.
    • Perpendicular central ray.
    • Best projection for facial bones.
    • Orbits, maxillae, and zygomatic arches are imaged.
    • Petrous ridges below the maxillae.
    • Blowout Fractures can be visualized.

    Modified Waters

    • Prone positioning with the MSP & MML perpendicular to the IR.
    • OML is 55° to the IR.
    • Acanthion is the exit point.
    • Perpendicular central ray.
    • Zygomatic bones are imaged.
    • Anterior wall of the maxillary sinus of the side up is visualized.

    Reverse Waters

    • AP Axial projection.
    • Supine positioning, with the MSP & MML perpendicular to the IR.
    • OML is 37° to the IR and the chin is up.

    Nasal Bone

    • Lateral projection.
    • Semiprone positioning with the MSP & IOML parallel to the IR.
    • IPL is perpendicular to the IR.
    • Reference point: 3/4 inch (old) or 1/2 inch superior to the tip of the mastoid process.
    • 15° caudad central ray.
    • Mastoid process is free from superimposition and projected below the shadow of the occipital bone.

    PA Tangential Position

    • Prone positioning.
    • IR is cranially inclined 15°.
    • Tape auricles forward.
    • Cheek against the IR.
    • Face rotated away from the side of interest.
    • MSP is 55° from the IR or 35° from vertical.
    • IOML is perpendicular to the IR.
    • Reference point: 1 inch superior to the tip of the mastoid process.
    • 15° cephalad central ray.
    • Mastoid process is free from superimposition and projected below the shadow of the occipital bone.

    Towne Method

    • AP Axial projection.
    • Supine positioning with the OML/IOML and MSP perpendicular to the IR.
    • Reference point: 2 inches above the glabella or 2.5 inches above nasion.
    • 30° caudad (OML perpendicular) or 37° caudad (IOML perpendicular) central ray.
    • Mandibular condyles and mandibular fossae of the temporal bones are imaged.
    • Closed-mouth: The condyle lies in the mandibular fossa.
    • Opened-mouth: The condyles lie inferior to the articular tubercle.

    Axiolateral Projection

    • Semiprone positioning with the head in a lateral position.
    • IPL perpendicular to the IR.
    • MSP parallel to the IR.
    • Closed-mouth and opened-mouth positions.
    • Reference point: 0.5 inch anterior and 2 inches superior to the upside EAM.
    • 25-30° caudad central ray.
    • TMJ anterior to the EAM is imaged.
    • Closed-mouth: Condyle lies within the mandibular fossa.
    • Opened-mouth: Condyles lie inferior to the articular tubercle.

    Schuller Method

    • Axiolateral oblique/lateral transcranial/axial transcranial projection.
    • Semiprone positioning with MSP rotated 15° toward the IR.
    • AML parallel to the transverse axis of the IR.
    • Reference point: 1.5 inches anterior to the EAM (sella turcica).
    • Mouth wide open.
    • Acanthion is the reference point.
    • Horizontal central ray.
    • Sphenoidal sinuses projected through the open mouth.
    • Petrous pyramids inferior to the floor of the maxillary sinus.

    Zanelli Method

    • Lateral transfacial position.
    • Lateral recumbent positioning with the head in a true lateral position, resting on the parietal.
    • MSP is 30° to IR.
    • Uppermost gonion is the entrance point.
    • Perpendicular central ray.
    • TMJ is visualized.

    Sinuses

    • Cross and Flecker identified the value of the erect position to visualize fluid levels and differentiate fluid shadows from pathology.

    Lateral Projection

    • Perpendicular central ray.
    • Sphenoidal sinuses are projected through the open mouth.
    • Maxillary sinuses and nasal fossae visualized.

    Rhese Method

    • PA Oblique position.
    • Seated erect positioning with zygoma, nose, and chin against the IR.
    • AML perpendicular to the IR and MSP 53° from the IR.
    • Upper parietal region is the reference point.
    • Perpendicular central ray.
    • Oblique image of the posterior and anterior ethmoidal sinuses.
    • Frontal and sphenoidal sinuses visualized.
    • Profile image of the optic canal is visualized.

    Law Method

    • PA Oblique position.
    • Seated erect positioning with zygoma, nose, and chin against the IR.
    • Neck is fully extended.
    • Uppermost gonion is the reference point.
    • 25-30° cephalad central ray.
    • Relationship of the teeth to maxillary sinuses is visualized.

    Mastoid

    • Modified Hickey Method.
    • AP Tangential position.
    • Supine positioning with the auricles taped forward and the face rotated away from the side of interest.
    • MSP is 55° from the IR or 35° from vertical.
    • IOML perpendicular to the IR.
    • IR caudally inclined 15°.
    • Reference point: 1 inch.
    • Sigmoid sinus, lateral portion of pars petrosa, tegmen tymphani, internal & external auditory meatuses, and the mastoid emissary vessel (when present) are visualized.

    Skull Planes, Points & Lines

    • Midsagittal Plane (MSP): Divides the skull into equal right and left halves.
    • Interpupillary Line (IPL): Line drawn between the centers of the pupils.
    • Acanthion: Point at the tip of the nasal spine.
    • Outer Canthus: Lateral (outer) corner of the eye.
    • Infraorbital Margin: Lower edge of the bony orbit.
    • External Acoustic Meatus (EAM): Opening of the ear canal.
    • Orbitalmeatal Line (OML): Line connecting the outer edge of the orbit to the EAM.
    • Infraorbitomeatal Line (IOML)/Frankfort Line: Line connecting the infraorbital margin to the EAM.
    • Acanthiomeatal Line (AML): Line connecting the acanthion to the EAM.
    • Mentomeatal Line (MML): Line connecting the chin (menton) to the EAM.
    • OML, IOML, and GML (Glabellomeatal Line): The angles between these lines are crucial for positioning during skull radiography.

    Skull Pathology

    • Basal Fracture: Fracture at the base of the skull.
    • Blowout Fracture: Fracture of the floor of the orbit.
    • Contre-Coup Fracture: Fracture on one side of a structure due to impact on the opposite side.
    • Depressed Fracture: Fracture causing a portion of the skull to be pushed inwards.
    • Le Fort Fracture: Bilateral horizontal fractures of the maxillae (upper jawbone).
    • Linear Fracture: Irregular or jagged fracture of the skull.
    • Tripod Fracture: Fracture involving the zygomatic arch, orbital floor/rim, and dislocation of the frontozygomatic suture.
    • Mastoiditis: Inflammation of the mastoid antrum and air cells in the mastoid bone.
    • Paget's Disease: Thickened, soft bone with a tendency for bowing and fractures.
    • Sinusitis: Inflammation of one or more paranasal sinuses (air-filled cavities in the skull).
    • TMJ Syndrome: Disorder of the temporomandibular joint (jaw joint).

    Skull Radiographic Projections

    • PA (Posteroanterior) Projection: Patient prone, MSP and OML perpendicular to the IR (image receptor).
    • AP (Anteroposterior) Projection: Patient supine, MSP and OML perpendicular to the IR.
    • Lateral Projection: Patient semiprone, MSP and IOML parallel to IR, IPL perpendicular to IR.
    • Caldwell Method: PA axial projection.
    • Waters Method: Parietoacanthial projection.
    • Stenvers Method: Posterior profile position of the skull to view the petrous bone.
    • Schuller Method: Verticosubmental projection to view the sphenoid sinuses.
    • Mayer Method: Axiolateral oblique projection of the petrous bone.
    • Modified Lysholm Method: Eccentric angle parieto-orbital oblique projection.
    • Hough Method: Parieto-orbital oblique projection to view the sphenoid strut.
    • Bertel Method: PA axial projection to view the inferior orbital fissures.
    • Pfeiffer-Comberg Method: Utilizes a leaded contact lens to localize foreign bodies in the eye.
    • Vogt-Bone-Free Position: Lateral and superoinferior projections used for detecting small or low-density foreign bodies in the eye.
    • Parallax Method: Two projections (lateral) to determine if a foreign body is within the eye.
    • Open-Mouth Waters Method: Modification of the Waters for better visualization of the sphenoid and ethmoid sinuses.
    • Hirtz Method: Variation of the Open-Mouth Waters for better visualization of the petrous bone and mastoid structures.

    Radiographic Projections for Specific Structures

    • Petrous Pyramid: Best visualized with the Caldwell, PA axial, and Stenvers projections.
    • Superior Orbital Fissure: Well visualized on the Caldwell PA axial projection at 15o caudal angle.
    • Inferior Orbital Fissure: Best visualized with the Bertel Method, PA axial projection.
    • Optic Canal (Foramen): Modified Lysholm Method, Hough Method, and PA projection with 10o cephalad angle.
    • Foreign Body in the Eye: Lateral projection for initial check.
    • Facial Bones: Lateral projection to visualize superimposed facial bones.
    • Sphenoid and Ethmoid Sinuses: Waters method and Schuller method.
    • Maxillary Sinuses: Waters method.
    • Sella Turcica: Waters method, Open-Mouth Waters method, and Stenvers method.
    • In addition to these projections, tomographic studies can be conducted to obtain detailed images of specific structures like the ears, jugular foramina, and rotundum foramina.*

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Skull Anatomy PDF

    Description

    This quiz covers detailed methods for skull projections including the Schuller/Pfeiffer method and the Modified Towne method. You will learn about patient positioning, central ray angles, and the anatomical structures demonstrated in each projection. Test your knowledge of radiographic techniques in skull imaging.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser