Imaging Notes Year 3 - finished Flashcards
What is McGregors Line (Basal Line)?
Measured: Line drawn from posterosuperior margin of hard palate to most inferior surface of occipital bone. The superior, (apical), aspect of the dens should not exceed 8mm above this line (10mm female)
Significance: Indicates basilar impression, Atlas occipitalisation, Bone softening conditions (OM, Pagets, fibrous dysplasia) RA
What are the Cervical views?
- AP open mouth
- AP Lower Cervical
- Lateral
- Right and Left Posterior Oblique
- Davis Series = Flexion and extension lateral (along with all other films)
What are the cervical lines of alignment in a lateral Cx view? What is the significance of interruptions/discrepancies in these lines?
▪ ALL, PLL, SLL ▪ Cervical canal width ▪ Georges Line (PLL) ▪ Angle of the Cervical Spine ▪ Ruth Jackson physiological Line ▪ Vertical line of stress (cervical body gravity Line) ▪ ADI ▪ Retropharyngeal and retro tracheal spaces
SIGNIFICANCE: Traces curvature of lordosis Spondylolisthesis Interruptions indicative of osteophytes Fractures/dislocations
What does the space between the PLL and the SLL indicate? What is the clinical significance?
Distance between PLL and SLL is spinal canal space <12mm = stenosis
What does the cervical measure, what are the measured landmarks and what is normal?
Measures the angle of lordosis in the cervical spine.
Measured: Midpoints of anterior and posterior tubercles of the atlas and a line through inferior endplate of C7. Perpendiculars are constructed if required.
Angle: 35-45 degrees normal lordosis
What does the Physiological Line of Stress (Ruth Jackson) measure?
How is it measured and what is normal?
What does an abnormal measurement signify?
Measures the line of gravity through the Cx spine
MEASURED BY: 2 lines and where they intersect:
1 - Along the posterior aspect of the dens
2 - Along the posterior aspect of C7
NORMAL:
Neutral: Should pass through C4/5 IVD
Flexion: Should Pass through C5/6
Extension: Should Pass through C4/5 posterior
SIGNIFICANCE:
Biomechanical compensation
What does the Atlanto-dental interspace (ADI) measure?
How is it measured and what is normal?
What does an abnormal measurement indicate?
The space between the front of the dens and the back of the C1 arch anteriorly.
MEASURED BY: Anterior aspect of dens and posterior aspect of anterior tubercle.
NORMAL:
1-3mm adults
1-5mm children
INDICATIONS: PARRS, Down Syndrome
List all of the lines of alignment in the Cervical Spine (6)
- Georges (PLL, ALL and SLL) for all of spine
- Physiological line of stress (Ruth Jackson)
- Angle of Cx. Spine
- Cervical body gravity line
- ADI
- Retropharyngeal and Retro tracheal space
List the lines of alignment in the Thoracic Spine (4)
- Thoracic curve angle
- Pedicular method of rotation
- Tracheal bifurcation level in pediatric to geriatric
- Scoliosis
What are the views of thoracic spinal imaging?
AP
Lateral
Specific rib views
What are the lines of alignment of a lateral of the thoracic spine?
▪ ALL, PLL, SLL
▪ Angle of the Thoracic Kyphosis
▪ Tracheal bifurcation
When look at the alignment of the Tx spine in an AP, the interpedicular distance should not be less than what?
14mm
Describe the 2 measuring systems for quantifying scoliosis deviation
Cobb Lippman Method:
- A line is drawn along superior border of cephalad (top) vertebrae.
- A line is drawn along inferior of caudad (bottom) vertebrae.
If endplates not visible then bottoms and tops of pedicles used.
Perpendicular lines are then drawn from each horizontal line, and the angle of their intersection measured.
Seven groups: 1: 0-20 degrees, 2: 21-30 degrees,3: 31-50 degrees,4: 51-75 degrees,5: 76- 100 degrees, 6: 101-125 degrees ,7: 126 and above,
Cobb method gives larger measurements then Risser technique by average of 25% or about 10 degrees.
Risser-Ferguson Method:
- The centres of the end (top and bottom) and apical vertebral bodies are identified. These points are then connected and the angle of intersection measured.
What can alter the tracheal bifurcation level?
Where is the tracheal bifurcation level at the ages:
1 - newborn?
2 - 10 yrs old?
3 - adult?
Infections
Tumours
Mechanical Influences
Newborn - T3
10 years old: T5
Adult: T6
What are the views in a lumbo-sacral series?
AP (tilt 15 degree SIJ)
Lateral
Oblique R & L
L5/S1 spot (AP and Lat)
What are all of the lines of alignment in the lumbar spine?
- George’s line (ALL,PLL,SLL)
- Ferguson’s line
- Lumbosacral disc angle
- McNab’s line
- Lumbar curve angle
- Ulman’s line
- Myerdings classification
- Sacral base angle
- Pedicle Rotation, Interpedicular distance
What is Meyerding classification used for? How is it measured?
Classifying spondylolisthesis.
Sacral base is divided into 4 equal parts. The relative slip of the vertebrae above is classified.
What is Ulman’s line? How is it measured?
Helps identify a spondylolisthesis.
Line extended upwards at a 90 degree angle to the superior surface of the sacral base at its anterior margin and it should clear the anterior inferior margin of the L5 body.
When look at the alignment of the Lx spine in an AP, the interpedicular distance should not be less than what?
20mm
What are the views of a pelvic and hip series?
AP widely collimated
Spot AP Hip
Frogleg
Lateral (uncommon due to superimposition)
What are the ages of ossification of the pelvis?
Three centres of ossification
1: Ilium ~ = 2 months fetal life
2: Ischium = 3 months
3: Pubis = 4 months
4: Ischial and pubic rami = 7 years
5: The ‘Y’ shaped cartilaginous physis of the three bones after puberty = 15yr
What are the ages of ossification of the femur?
Femur:
1: Centre of the head = 1 year
2: Greater trochanter = 3 years
3: Lesser trochanter = 12 years
What are the lines of alignment of the hip and pelvis?
- Acetabular depth
- Acetabular angle
- Symphysis pubis width
- Shenton’s line
- Ilio-femoral line
- Skinners line
- Kohlers Line (Measurement of protrusio acetabuli)
- Klein’s line (Slipped epiphysis in children)
- Femoral angle
- Measurement of protrusio acetabuli
- Hip joint width (Tear drop distance)
What are the areas measured in for hip joint width and what are the normal values? What does abnormal values signify?
▪ S: Superior Joint Space:
The space from the most superior aspect of articular surface of femur and adjacent acetabular cortex.
▪ A: Axial Joint Space:
Space btw the femoral head and acetabulum immediately lateral to acetabular notch.
▪ M: Medial Space (also Teardrop distance):
Space between the most medial surface of femoral head and opposing acetabular surface.
NORMAL:
Superior: 3-6 (4mm average)
Axial: 3-7 (4mm average)
Medial: 6-11 (8mm average)
SIGNIFICANCE \: Various disorders. (some examples) Superior : most common DJD Axial: DJD, inflammatory arthritides Medial: DJD, RA. Effusion
Medial Teardrop distance: if exceeds 11mm or > 2mm discrepancy from side to side then hip disease is most likely present. (even 1mm difference can indicate disease).
Early sign in Perthes, inflammatory conditions, septic arthritis.
How is the Ilio-femoral line measured?
What is normal?
What is the significance of abnormal?
MEASURED BY:
A line along lateral margins of the ilium should continue as an unbroken curve along the superior margins of the femoral neck.
NORMAL:
Even appearance bilaterally
SIGNIFICANCE: Congenital dysplasia SFCE Dislocation #
How is the Acetabular Angle measured?
What is normal?
What is the significance of abnormal?
MEASURED BY:
Base Line: A horizontal line through the triradiate cartilage at its junction with the pelvic rim.
A 2nd oblique line connecting the lateral and medial acetabular surfaces is constructed and intersected with the base line.
NORMAL:
Avg. = 20 degrees
New born = < 34
SIGNIFICANCE:
> seen in dysplasia and congenital hip dislocations.
< often in down syndrome.
What are the views of a knee series?
AP Lateral Intercondylar Skyline Medial oblique
What are the lines of alignment in the knee?
- Q angle
- Patella Alta/Baja
- Femoral angle
- Tibial angle
What are the views of an Ankle series?
AP
Lateral
Oblique
What are the views of a foot series?
Dorsal Plantar
Lateral
Oblique (medial)
What are the lines of alignment in the ankle/foot?
- Tibial/ fibular angles
- Boehlers
- Arches
What is a normal heel pad measurement?
< 20mm
Significance:
Achondroplasia,
Inflammatory conditions
How to assess the longitudinal arch of the foot?
Compare the height from the curvilinear line extending along the horizontal arch to the base line between the calcaneus and the base of the 1st MTP.
Significance: Pes Planus (Dropped arches) Pes Cavus (High Arch)
What are the views in a shoulder series?
AP AP internal rotation AP external rotation Axial Scapular Y Shoulder AC Joints (spot, weighted
When would you do an AP of a shoulder?
GH Arthritis, Coracoid Process # Glenoid Fracture Proximal Humerus # Post. GH Instability AC joint position AC arthritis RTC calcifications Acromial spurring
When would you do an AP with external/internal rotation of a shoulder?
GH Arthritis
Coracoid Process #
Glenoid Fracture
Prox. Humerus Fracture.
When would you do an axillary view of a shoulder?
GH narrowing (best view)
Os Acromion
Glenoid erosion
Humeral head subluxation.
When would you do a scapular Y view of the shoulder? What does it demonstrate?
Shoulder Dislocation
Proximal Humerus Fracture
Scapula Fracture
Demonstrates: Lateral projection of scapular body and humeral head overlapping the glenoid.
What are the lines of alignment for the shoulder?
Width of joint space
How is the humeral axial angle measured?
What is normal?
What is the significance of abnormal?
MEASURED BY:
Greater tuberosity apex to where medial cortex of diaphysis becomes a thin line. Line down the axis of the humerus.
NORMAL:
60-62 degrees
SIGNIFICANCE: # surgical neck
How is the Acromiohumeral Joint Space measured?
What is normal?
What is the significance of abnormal?
MEASURED BY:
Inferior aspect acromion and apices of humerus.
NORMAL:
9mm avg.
SIGNIFICANCE:
>7mm indicates rotator cuff tear, degenerative tendonitis.
> 11mm indicate post traumatic subluxation, dislocation, joint effusion, brachial plexus lesions.
How is the Acromioclavicular Joint Space measured?
What is normal?
What is the significance of abnormal?
MEASURED BY:
2 points on lat clavicle and 2 points acromion.
NORMAL:
- 3mm male
- 9mm female
SIGNIFICANCE:
< seen in DJD
> arthritides, Trauma
What are the views in an elbow series?
– AP
– Lateral Flexion
– Medial Oblique
– +- supination or pronation AP
What are the lines of alignment of the elbow?
- Carrying angle,
* General relationship of radius ulna humerus
What are the views in a hand/wrist series?
PA:
Carpal joints, distal radio-ulnar joint, radio-carpal and ulnocarpal joints.
Lateral: Displays carpals (particularly lunate) alignment, esp. in relationship to distal radius.
Lateral Oblique (PA) (zither player, ball catcher): Metacarpal-phalangeal joints
Medial Oblique (PA): Radio-carpal and ulnocarpal joints
Scaphoid:
Ulna deviated and flexed.
What are the lines of alignment of the wrist?
- General alignment wrist
* Carpal Alignment
What are the views in a chest series?
PA
Lateral
Rib views
*note: all chest views are taken on full inspiration unless told otherwise
Looking at a normal PA of the chest we should be able to see:
Lung fields Heart Great vessels Ribs Shoulder girdles Thoracic spine Upper abdomen
PA chest structures to note:
Trachea – bifurcation Aortic arch Right/left atrial borders Left ventricular border Right/left cardio-phrenic angles Right/left costo-phrenic angles Right/left pulmonary blood vessels Scapula Clavicle Breast contour (in females) Liver and Stomach – gastric air bubble in fundus
Looking at a normal lateral of a chest we should be able to see:
Lung fields Heart Great vessels Ribs Sternum Thoracic spine (lucent due to air masses)
Lateral chest structures to note:
Sternum Manubrium/Angle of louis R / L domes of diaphragm Trachea Retro-sternal space Retro-cardiac space Heart Aortic arch Ribs
What are the lines of alignment for a chest xray series?
- Trachea
- Measurement of normal heart, general positioning
- Cardio phrenic, Costophrenic
- Diaphragmatic relationships
What are the things we should consider in each of the letters of AABCS?
A = All:
- Ensure all your films asked for are there
- Patients identifying details are present (i.e. The X-rays are of the patient you requested)
- All Bones are present which should normally be present
A = Alignment
- Alignment of bones with one another in relation to articulation with other bones
B = Bone Quality
- Trabecular patterns
- Density of bones (i.e. high density = whiter film as opposed to low density films)
- Medullary cavities
- Cortical continuity, thickness and integrity
- Periosteal involvement
C = Cartilage
- Note joint space and symmetry
S = Soft tissues
- Note any increase in density (i.e. soft tissue injury) or absence or presence of.
What does VINDICATE stand for?
V: Vascular I: Infection N: Neoplasm D: Degenerative I: Iatrogenic / Idiopathic: C: Congenital: A: Autoimmune: T: Trauma: E: Endocrine (+ nutritional, metabolic):
