RADT 211 EXAM #2 - THEORY

What bones are part of the CRANIUM

• frontal bone

• 2 parietal bones

• 2 temporal bones

• occipital bone

• sphenoid bone

• ethmoid bone

What is the skull cap also called

calvarium

What bones are part of the SKULL CAP

• frontal bone

• occipital bone

• right parietal bone

• left parietal bone

What bones are part of the SKULL FLOOR

• sphenoid bone

• ethmoid bone (crista galli)

• right / left temporal bone

What are the SURFACE LANDMARKS for skull

• glabella

• nasion

• acanthion

• mentum/mental point

• gonion (angle of mandible)

• TEA (top of ear attachment)

• IPL (interpupillary line)

• SOM (supraorbital margin)

• IOM (infraorbital margin)

• outer canthus

• inner canthus

The glabella is located on the ____ cranial bone

frontal

Which cranial bone houses the organs for hearing and equilibrium

Temporal bone

Which aspect of the skull is most vulnerable to fracture

Squamous portion of the temporal bone

The optic foramen is located on the _____ bone

Sphenoid

What are the PORTIONS of the temporal bone

• mastoid portion

• squamous portion

• petrous portion

What part of the ethmoid bone is visibly part of the skull floor

Crista galli

What are the PORTIONS of the frontal bone

• vertical/squamous portion

• orbital portion

Describe MESOCEPHALIC head shape (skull morphology)

skull of average shape

• width 75-85% of length

• petrous pyramids 47 degrees from MSP

Describe BRACHYCEPHALIC head shape (skull morphology)

• width is 80% or more of length

• petrous pyramids 54 degrees (greater than 47 degrees) from MSP

Describe DOLICHOCEPHALIC head shape (skull morphology)

• width is less than 75% of length

• petrous pyramids 40 degrees (less than 47 degrees) from MSP

What does GML stand for (positioning line)

Glabellomeatal line

• glabella to EAM

What does OML stand for (positioning line)

Orbitomeatal line

• outer canthus to EAM

What does IOML stand for (positioning line)

Infraorbitomeatal line

• infraorbital to EAM

• AKA Reids Base Line

• 7-degree difference from OML

What does AML stand for (positioning line)

Acanthiomeatal line

• acanthion to EAM

What does LML stand for (positioning line)

Lipmeatal line

• middle of lip to EAM

What does MML stand for (positioning line)

Mental point to EAM

What does EAM stand for

External Auditory/Acoustic Meatus

Describe the positioning and technical considerations for SKULL positioning

• kV range → 75-85

• minimum 40 inches (100 cm) SID

• small focal spot

• 10 × 12 IR with collimation

• objects that need to be removed or may cause artifacts

  • jewelry

  • false teeth

  • hearing aide

  • eye glasses

  • hair ties/clips

  • wigs / extensions

Describe TRUE PA skull positioning

• OML perpendicular to IR

• MSP perpendicular to IR

• CR 0 degrees, exit at glabella

• suspended breathing

Describe TRUE PA skull criteria

• entire skull visualized

• no rotation (MSP)

• petrous pyramids fill the orbits

• frontal bone visualized

Describe PA CALDWELL skull positioning

• OML perpendicular to IR

• MSP perpendicular to IR

• CR 15 caudal angle, exit at nasion

• suspended breathing

Describe PA CALDWELL criteria

• entire skull visualized

• no rotation (MSP)

• petrous ridges in lower 1/3 of orbit

• frontal bone visualized

Describe AP AXIAL TOWNES skull positioning

• MSP perpendicular to IR

• CR 2 ½ inches above glabella

• PREFER OML perpendicular to IR

  • CR 30 degrees caudal

• SETTLE IOML perpendicular to IR

  • CR 37 degrees caudal

Describe AP AXIAL TOWNES skull criteria

• no rotation (look at petrous pyramids … should be symmetrical)

• foramen magnum with dorsum sellae in center

• occipital bone visualized

• mastoid air cells aerated visualized

Describe PA AXIAL HAAS skull positioning

• OML perpendicular to IR

• MSP perpendicular to IR

• CR 25 degrees cephalic, exit 1 ½ inch above nasion

• reverse of Townes

Describe PA AXIAL HAAS skull criteria

• magnification of occipital bone evident

• dorsum sellae appears larger within foramen magnum

• occipital bone visualized

Describe LATERAL skull positioning

• need true lateral position of head

• perform both right and left sides

• IR landscape 10 × 12

• MSP parallel to IR

• IPL perpendicular to IR

• IOML plane perpendicular to front edge of IR / parallel to top edge of IR

• CR 2 inches superior to EAM

Describe LATERAL skull criteria

• sella turcica in profile

• visualizes temporal/parietal bone areas, part of occipital bone

Describe ROTATION on a LATERAL SKULL radiograph

• anterior to posterior separation

• make sure MSP is parallel to IR

• look at →

  • mandibular rami

  • EAM

  • greater wings of sphenoid

Describe TILT on a LATERAL SKULL radiograph

• inferior to superior separation

• make sure IPL is perpendicular to IR

• look at →

  • orbital plates

  • lesser wings of sphenoid

Describe EXCESSIVE FLEXION / EXTENSION on a LATERAL SKULL radiograph

• make sure IOML plane is perpendicular to IR

What bones meet at the CORONAL suture

Parietal bones and Frontal bone

What bones meet at the LAMDOIDAL suture

Parietal bones and Occipital bone

What bones meet at the SQUAMOSAL suture

Temporal bone and Parietal bone

What bones meet at the SAGITTAL suture

Left and Right Parietal bones

The ANTERIOR end of the sagittal suture is called what

Bregma (junction point)

The POSTERIOR end of the sagittal suture is called what

Lambda (junction point)

The angle between the midsagittal plane and the long axis of the petrous portion of the temporal bone in the BRACHYCEPHALIC skull is

47 degrees or greater

The midline point at the junction of the upper lip and the nasal septum is called what

Acanthion

There is a _______ difference between the OML and IOML (Reids Base line)

7-8 degree

Which positioning error is present if the orbital roofs are not superimposed on a lateral skull radiograph

Tilt

Which skull bones does the SPHENOID bone articulate with

• ethmoid bone

• frontal bone

• occipital bone

• right and left parietal bones

• right and left temporal bones

Which skull bones does the OCCIPITAL bone articulate with

• sphenoid bone

• right and left parietal bones

• right and left temporal bones

• C1

Which skull bones does the PARIETAL bone articulate with

• sphenoid bone

• opposite parietal bone

• frontal bone

• occipital bone

• temporal bone

Which skull bones does the FRONTAL bone articulate with

• sphenoid bone

• ethmoid bone

• right and left parietal bones

Which skull bones does the TEMPORAL bone articulate with

• sphenoid bone

• parietal bone

• occipital bone

Which skull bones does ETHMOID bone articulate with

• sphenoid bone

• frontal bone

Describe LATERAL SELLA TURCICA positioning

• IPL perpendicular to IR

• MSP parallel to IR

• IOML perpendicular to front edge of IR / parallel to top edge of IR

• CR ¾ inches anterior and ¾ inches superior to EAM

• close collimation

Describe LATERAL SELLA TURCICA criteria

• sella turcica and clivus in profile

• anterior and posterior clinoid processes superimposed

• greater and lesser wings of sphenoid superimposed

What views best visualize the PATELLA

• PA

• Lateral

• Merchant (superoinferior)

• Sunrise/Skyline (inferosuperior)

• Hughston (inferosuperior)

• Settegast (inferosuperior)

Describe PA PATELLA positioning

• CR perpendicular to mid-patella area (popliteal crease)

• rotate knee 5 degrees medial for true AP

Describe LATERAL patella positioning

• CR perpendicular to distal patellofemoral joint

• flex knee 5-10 degrees

Describe MERCHANT patella positioning

• superoinferior projection

• knee flexed 40 degrees

• CR angled 30 degrees from horizontal

Describe SUNRISE/SKYLINE patella positioning

• inferosuperior projection

• 40-45 degree flexion of knee

• CR 10-15 degrees from lower leg (centered to patellofemoral joint)

Describe HUGHSTON patella positioning

• inferosuperior projection

• knee flexed 40 degrees

• CR 15-20 degrees to lower leg

Describe SETTEGAST patella positioning

• inferosuperior projection

• flex knee 90 degrees

• CR 15-20 degrees to lower leg

What views will best visualize the INTERCONDYLAR FOSSA

• Camp-Coventry

• Holmblad

• Beclere

Describe CAMP-COVENTRY intercondylar fossa positioning

• PA

• flex lower leg 40-50 degrees

• CR perpendicular to lower leg / centered to popliteal crease

Describe HOLMBLAD intercondylar fossa positioning

• PA

• lean pt forward 20-30 degrees (leg forms 70 degree angle)

• CR perpendicular to lower leg / centered to popliteal crease

Describe BECLERE intercondylar fossa positioning

• AP

• knee flexed 40-50 degrees

• CR perpendicular to lower leg / centered ½ inch distal to apex of patella

When do you utilize an angle for a KNEE SERIES

Lateral →

• angle 5-7 degrees cephalic

• compensates for the medial condyle being inferior to lateral condyle, superimposed them

AP →

• 18 cm = angle 5 degrees caudal

• 19-24 cm = no angle

• 25 cm + = angle 5 degrees cephalic

• opens tibiofemoral joint better (?)

Describe the positioning/criteria for a MORTISE OBLIQUE ankle

• rotate ankle 15 degrees medially until intermalleolar plane is parallel to IR

• CR midway between malleoli

• visualizes whole ankle joint open and malleoli in profile

Describe the positioning/criteria for a 45-DEGREE OBLIQUE ankle

• rotate ankle 45 degrees medially

• CR midway between malleoli

• visualizes the distal tibiofibular joint on lateral aspect of ankle

What is the anatomy best visualized with a GRASHEY

the glenoid cavity

What is the anatomy best visualized with a NON-TRAUMA LAWRENCE

• lesser tubercle in profile

• coracoid process in profile

• demonstrates the glenohumeral joint

What is the anatomy best visualized with a TRAUMA LAWRENCE

• lateral view of shoulder/humerus through chest cavity

• should be visualizing a 90-degree difference from neutral AP

What is the anatomy best visualized with a SCAPULAR Y LATERAL for a trauma shoulder

• scapula in lateral position, humerus superimposing

• helps to see dislocations of shoulders

  • under the coracoid process → anterior dislocation

  • under the acromion process → posterior dislocation

Describe the epicondylar plane and anatomy best visualized on an INTERNAL ROTATION shoulder

• epicondylar plane perpendicular to IR

• lesser tubercle in profile

Describe the epicondylar plane and anatomy best visualized on an EXTERNAL ROTATION shoulder

• epicondylar plane parallel to IR

• greater tubercle in profile

Describe the epicondylar plane and anatomy best visualized on an AP NEUTRAL shoulder

• epicondylar plane somewhere in between, wherever pt has it in neutral position

• nothing in profile