What are Hounsfield Units?
used universally in CT scanning
Radiodensity of air: -1000
Radiodensity of water: 0
Radiodensity of bone: +1000
Two different types of thrombi
Arterial: made of platelet aggregates
Venous: made of fibrin and RBC
Most common places to get venous thrombi and what are the consequences of this?
DVT
This can lead to a PE
(or can lead to a stroke if there is a congenital heart defect)
Most common places to get dangerous arterial thrombi and what are the consequences of this?
Carotids, mural etc
can result in MI, unstable angina, ischamic stroke, manifestations of PAD (eg; acute limb ischaemia)
What increases risk of mural thrombi (thrombi that attach to the wall of a blood vessel and cardiac chamber, seen in aorta or heart)
- Atrial Fibrillation
- Heart valve replacement
- DVT
- Acute MI
- Genetic coagulation disorder
list the different stone types of nephrolithiasis (Kidney Stones)
Radiopaque:
- Calcium oxalate
- Struvite (triple phosphate) (can lead to staghorn calculi)
Radiolucent:
- Uric Acid
- Cystine
Associations/causes of a perianal/abdominal fistula?
- Diverticulitis
- Crohns Disease
- Bowel/pelvic infections
- TB
- iatrogenic (post-surgical)
- Childbirth
- Pelvic malignancies
What is Gliosis and when does it occur?
A non-specific reactive change of glial cells in response to the damage to the CNS (brain/spinal cord)
Pleural Plaques (lesions of scar tissue, sometimes calcified) are caused because of?
- Asbestos exposure (20-30 post)
Diffuse plerual thickening can be from?
- Diffuse pleural fibrosis
- Asbestos related pleural disease
- Malignant pleural mesothelioma
*
Pseudomyxoma peritonei
Progressive intraperitoneal mucinous ascites
Due to a mucin-producing neoplasm
Most commonly of the appendix “appendiceal mucocele”
Stages of CHF on a plain chest radiograph
- Upper Lobe Pulmonary Veins Enlarge
- Upper usually smaller or equal to LL’s (change art:bronch)
- Cardiomegaly
- Interstitial Changes
- Peribronchial cuffing/doughnut sign: describes haziness/increased density around bronchus or large bronchiole walls.
- Kerley- B lines
- Hazy contour of vessels
- Thickened interlobar fissure
- Pulmonary oedema
- alveolar oedema; sometimes a central perihilar pattern, outward from the hilum “batwing”.
- **air bronchograms can be seen with this**
- Pleural effusion
How do alveoli communicate?
Via the ‘Pores of Kohn”
