9 - Principles of Interpretation of Axial skeleton

Question 1

Ancillary projections of the skull

Answer 1

Question 2

Which projection is best used to identiify frontal sinuses?

Answer 2

Rostrocaudal projection

Question 3

Which projection is best used to identiify right maxillary dental arcade or right tympanic bulla? (And vice versa)

Answer 3

Open mouth left 20 degrees-ventral, right dorsal

Question 4

Which projection is best used to identiify the right mandibular arcade? (and vice versa)

Answer 4

Open mouth left 20-degree dorsal - right ventral

Question 5

Which two views are best used to visualise the nasal cavity?

Answer 5

Open mouth ventral 20-degree rostral-dorsocaudal (attached picture similar projection without angulation)

Intraoral dorsoventral projection

Question 6

Which projection is best used to visualise tympanic bullae? And in brachys / cats?

Answer 6

Intraoral rostrocaudal

Brachys / cats: Rostro 10 degrees ventral - caudodorsal

Question 7

Which projection is best used to identiify the right bulla / TMJ? (And vice versa)

Answer 7

Left 20 degree rostral - right caudal

Question 8

What are the advantages of high kVp and low mAs / low kVp and high mAs techniques in skull radiography?

Answer 8

Low kVp, high mAs = Increased contrast, makes bone detail better at expense of ST.

High kVp, low mAs = Better for STs

Seems inverse…. investigate if needed!

Question 9

How do we mark oblique skull radiographs?

Answer 9

L positioned dorsal; R positioned ventral -> indicates which structure is dorsal and which is ventral

Question 10

Which projection is used to identify right maxillary tooth roots in horses (only oblique specifically demonstrated in book….)?

Answer 10

Left 45-degree ventral - right dorsal oblique

Question 11

Vertebral formulae of cat, dog and horse?

Answer 11

Cat, dog: C7; T13; L7; S3; Cd variable

Equine: C7; T18; L6; S5; Cd15-21

Question 12

Which cervical vertebra has elongated transverse processes in the dog / horse?

Answer 12

C6

Question 13

Where is the anticlinal process typically located?

Answer 13

T10 or T11

Question 14

The ventral aspect of which vertebrae may be indistinct in the dog, and confused with aggressive process?

Answer 14

L3 and L4 (Diaphramagtic insertion)

Question 15

Which radiographic factors should be used for spinal radiography?

Answer 15

Low kVp, High mAs -> maximise contrast to evaluate bone

Opposite in the horse due to large size (reduced exposure time)

Question 16

What are the most common congenital malformations at: 1) Cervicothoracic junction

2) thoracolumbar junction
3) Lumbosacral junction (and associated predispositions)

Answer 16

1) Vestigial ribs C7 -> clinically silent. In people, association with horners
2) Altered T13 rib morphology
3) Transitional sacralised L7 -> LS disc protrusion, nerve root compression