The Skull Flashcards
The floor of the orbit is composed of the ______
medially and the _______ laterally.
maxilla medially and the zygoma laterally.
The frontal bone and parietal bones are connected by the
coronal suture.
The cranial bone located on the medial and posterior wall is the
ethmoid.
The cranial bone located at the lateral wall of the apex of the orbit is the
sphenoid.
The suture that joins the parietal and temporal bones is the
squamosal suture.
The occipital bone and parietal bones are connected by the
lambdoidal suture
The infant skull has six areas of incomplete ossification, termed the
fontanels.
Which skull landmark is located at the junction of the frontal and nasal bones in MSP?
The nasion is located in the MSP, at the junction of the frontal and nasal bones.
Which skull type is characterized as deep from vertex to base, narrow from side to side, and long from front to back?
The dolichocephalic skull is deep from vertex to base, narrow from side to side and long from front to back.
Which positioning baseline is formed when the outer canthus and EAM are connected?
The orbitomeatal line (OML) is formed by the connection of the outer canthus and the EAM.
Baseline positioned perpendicular to the IR on the lateral projection of the cranium.
interpupillary line
The CR is angled ________ for the PA Axial Projection (Caldwell) and you center it to exit at the level of the _____.
15 degrees caudal
exit at the Nasion
Which cranial bones are joined at the sagittal suture?
A) Parietals
B) Frontal and parietals
C) Occipital and parietals
D) Temporal and sphenoid
The Parietals
The foramen magnum is located in the:
A) Temporal bone
B) Sphenoid bone
C) Occipital bone
D) Inner ear
Occipital Bone
Which of the following structures are parts of the bony orbit?
(1) Sphenoid
(2) Palatine
(3) Maxilla
A) 1 and 2 only
B) 1 and 3 only
C) 2 and 3 only
D) 1, 2, and 3
1, 2, & 3
The bone of the anterior and superior portion of the cranium is the:
A) Occipital bone
B) Temporal bone
C) Frontal bone
D) Sphenoid bone
Frontal Bone
The greater and lesser wings are portions of the:
A) Ethmoid bone
B) Temporal bone
C) Frontal bone
D) Sphenoid bone
Sphenoid Bone
Which of the following items must be removed before a radiographic examination of the skull?
(1) Eyeglasses
(2) Contact lenses
(3) Hairpins
A) 1 and 2 only
B) 1 and 3 only
C) 2 and 3 only
D) 1, 2, and 3
1 & 3 Only
Which category of skull morphology is used to characterize a skull of average size and shape?
A) Mesocephalic
B) Dolichocephalic
C) Brachycephalic
D) Extracephalic
Mesocephalic
Which baseline is used to position the PA projection of the cranium, and what is its proper position in relation to the image receptor?
A) OML; perpendicular
B) OML; parallel
C) IOML; perpendicular
D) IOML; parallel
A) The OML is positioned perpendicular to the IR.
Which projection of the cranium demonstrates the petrous ridges in the lower third of the orbits?
A) PA axial (Caldwell method)
B) AP axial (Towne method)
C) SMV (Schüller method)
D) PA axial (Haas method)
The PA Axial (Caldwell)
What is another name for the angle of the mandible? A) Inion B) Vertex C) Nasion D) Gonion
Gonion
The junction of the eyelids at the lateral margin is the:
A) Outer canthus
B) Inner canthus
C) Glabella
D) Gonion
Outer Canthus
An image of a properly positioned PA projection of the cranium will demonstrate the:
A) Petrous ridges in the lower third of the orbits
B) Petrous ridges filling the orbits
C) Petrous ridges symmetrically on each side of the foramen magnum
D) Petrous ridges superimposed
Petrous Ridges filling the orbits
What is the line extending across the front through both eyes?
A) Midsagittal
B) Midcoronal
C) Interpupillary
D) Superciliary
Interpupillary
What is the line extending from the EAM to the outer canthus?
Orbitomeatal Line
What is the name of the smooth elevation between the superciliary arches?
glabella
What is the lateral aspect of each orbit: where the two eyelids originate?
Outer canthus
For the AP Axial (Towne) of the skull, how many degrees and which direction should the CR be directed when the OML is perpendicular to the IR?
30 Degrees caudal
Which projection of the skull can be correctly performed with the CR angled 15 degrees caudad?
PA Axial, Caldwell
With reference to the patient, where should the IR be centered for the PA Skull?
Nasion
Which positioning landmark is located at the base of the nasal spine?
Acanthion
With which cranial bone does the first cervical vertebra articulate?
Occipital
Which structure should be projected within the shadow of the foramen magnum on a well positioned AP Axial (Towne) projection radiograph of the skull?
A) Petrous Pyramids
B) Posterior Cervical Arch
C) Inion
D) Dorsum sellae
D) Dorsum sellae
The bregma in an adult would be referred to as what in an infant?
A) Posterior fontanel
B) Anterior fontanel
C) posterior sulcus
D) anterior fissure
B) Anterior fontanel
What type of fracture to the floor of the orbit will result from a direct blow to the eye?
A) Blow out fracture
B) Colles’ fracture
C) Compression fracture
D) Trimalleolar fracture
A) Blowout fracture
If the orbitomeatal line is perpendicular to the image receptor for an AP axial (Towne) projection, how much caudal angle is required?
A) 25 degrees
B) 40 degrees
C) 37 degrees
D) 30 degrees
D) 30 degrees
What is the name of the part of the temporal bone that houses the organs of hearing and balance?
A)Squamous
B)Mastoid
C)Petrous
D)Alveolar
C) Petrous
Which cranial suture separates the temporal from the parietal bone? A)Lambdoidal B)Coronal C)Squamosal D)Sagittal
C) Squamosal
What is the name of the large opening in the base of the cranium through which the spinal cord passes?
A)Foramen magnum
B)Foramen lacerum
C)Optic foramen
D)Foramen ovale
A) Foramen magnum
The orbital plates are part of the _________ bone.
A)Sphenoid
B)Frontal
C)Ethmoid
D)Temporal
B) Frontal
Which of the following projectionsis also referred to as the Rhese method?
A)Parieto-orbital oblqiue projection
B)PA projection
C)AP axial projection
D)Parietoacanthial projection
A) Parieto-orbital Projection
Each orbit is composed of ______ different bones; which are:
7 bones: frontal, sphenoid, ethmoid, maxilla, zygoma, lacrimal, and palatine
