LSRC Flashcards
What are the commonly used medical imaging techniques?
Plain film radiography, fluoroscopy, MRI, ultrasound, computed Tomography, Nuclear medicine imaging.
Explain plain film radiography.
X-ray passes through posterior to anterior. Radio dense objects appear brighter. Used to evaluate fractures, chest pain, difficulty breathing. Quick and low cost - 2D difficult to interpret.
Explain fluoroscopy and it’s uses.
Continuous pulsed x-ray produces a series of images. Images can appear in any plane.Contract dye can be used for seeing more detail.
Used to evaluate GIntract and sailography (tear ducts and salivary glands)
It can record multiple images but has a variable radiation dose and 2D
Explain the concept of ultrasound, what it’s used for and pros and cons
Probe to skin surface, high frequency sound waves reflected shows different density to structures. Antenatal evaluation, abdominal organs and vessels soft tissue and echocardiography. Very accessible, mobile, no radiation - relies on operator skill, reduced resolution on deeper structure.
Explain the concept of a CT scan, it’s uses, pros and cons.
X-ray rotates around patient, passes through patient at different angles picked up by a detector and patient is moved through scanner. Images can be viewed in any plane, 3D image that gives lots of information. Radiation dose is higher more expensive.
Used for trauma, neurological signs, acutely unwell patients, cancer staging, vascular disease.
Explain how an MRI scan works, it’s pros and cons and clinical uses.
The magnetic energy lines up the protons then makes them spin creating the 3D image. It avoids radiation dose, great for assessing inflammation and soft tissue. Can causes symptoms of claustrophobia.
Assessing joints, bones and heart.
How does Nuclear medicine imaging work?
Uses radioactive tracer, tracer admits gamma rays which are detected on a gamma camera.
Part of hybrid imaging used with PET or CT scans. Radiation dose is higher.
Used for looking at oestoblastic activity associated with bone cancer. Pulmonary embolisms.
What are the different epithelial cell types?
Cuboidal - all nuclei of similar round size cells with hexagonal shape
Columnar - long thin, all attached to basement membrane all similar size.
Squamous - thin squashed nuclear shape.
Different types of layers of epithelial cells
Pseudostratified - cells all touch basement membrane, nuclei long and thin, appears to have lots of layers but doesn’t.
Stratified - contains multiple layers tightly packed.
Simple - one single layer of cells.
Keratinised - cells at the top full of keratin with no organelles like in the skin.
What is the difference between dense vs loose connective tissue?
Loose - not completely packed, with spaces for diffusion.
Dense - collagen runs in straight lines, very thick pinker.
What are the different mucosa layers?
Laminate propria- connective tissue
Epithelium -
S mucosa - thin layer of muscle laminate ties the lamina propria.
What are the functions of apical, basal and lateral specialisation.
Apical - always divides from the back to form microvilli
Lateral - tight junctions for movement of extra cellular fluid.
Basal - structural support for epithelium.
Where would you find different types of connective tissue?
Loose connective tissue - around blood vessels found in between many organs
Dense regular - tendons and ligaments, haemopoietic tissue (bone and lymphatic)
Dense irregular - sub mucosa of digestive tract, lymph nodes, fibrous capsules of joints.
What is commonly found in connective tissue?
Macrophages, adipocytes, mast cells- release histamine makes arterioles and capillaries leaky.
Fibroblasts- makes the actin cytoskeleton
What are the macromolecules?
lipids, protein, nucleotide acid
