Cardiac Radiology Flashcards
Describe the positioning of dogs and cats for thoracic radiographs
Right and left lateral images
-patient is positioned on the table with the dependent side down and marked with a lead marker to indicate the dependent side in the collimated area as right (R) or left (L).
Ventrodorsal (VD) image
-patient placed in dorsal recumbency. Using a V-trough helps keep the patient’s spine and sternum aligned.
The thoracic limbs are taped together evenly and pulled forward with the patient’s muzzle placed between the limbs
Dorsoventral (DV) image
Ventral recumbency without the legs taped. The comfort of the patient is of utmost importance.
The thoracic limbs are pulled cranial and abducted. The anatomic landmarks are the same as for a ventrodorsal image.
Standing lateral
Standing erect
Recumbent VD with horizontal beam
Describe how the assessment of a heart radiograph is made
Recognise any artefacts
Assess technical quality
Assess everything but heart/lungs
Assess respiritory system
Assess the cardiac silhouette
Describe the radiographic appearance and relative dimensions of the normal heart
Cardiac size can be very difficult to evaluate
- breed and age variation in dogs.
Dog:
Rules of thumb for lateral (3.5 rib spaces max)
Rules of thumb for DV (2/3 of width of thorax at rib 6 max)
Cat:
Width about 2 rib spaces
Height about 2/3 thorax
appearance of a lemon
Recognise the sites of cardiac chambers on lateral and dorso-ventral images of the heart
Discuss the limitations of cardiac radiography
Difficult to generate radiographs of diagnostic quality:
-movement blur
-wide radiographic contrast
-interpretation!
-breed normals/age normals
i-nspiratory/expiratory
Explain what angiography is
Selective vs non-selective
Selective allows precise identification of chamber/vessel outline
Valve disease/congenital defects
Provides DEFINITIVE diagnosis
Largely replaced by cardiac ultrasound (echocardiography)
Discuss indications for angiography
Visualise the abnormalities with blood flow/ valve issue
