Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Human Anatomy ppt lectures Topic 12 Principles Of Radiology Notes. - anatomy ppt free download human anatomy ppt lectures, medicine notes ppt, anatomy handwritten notes pdf, mbbs 1st year anatomy notes pdf download, best anatomy notes pdf, human anatomy notes pdf, anatomy easy notes pdf, anatomy notes online, anatomy short notes, Anatomy ppt, Powerpoint Presentations and lecture notes.
Radiology
? Means Science of radioactive substances and high energy radiations.
? Is a branch of medicine concerned with use of radiant energy or radioactive
material in the diagnosis and treatment of diseases.
Discovery of X Rays by...
WC Roentgen
In the year...
1895
Classification of radiological procedures
? Diagnostic radiology
? Interventional radiology
? Computed tomography (CT)
? Magnetic resonance imaging (MRI)
? Ultrasonography (USG)
? Mammography
? Interventional radiology
X ray generator
Diagnostic radiology
? Plain radiography
? Fluoroscopy
? Observing moving body structures
Plain radiography
? A/k/a X Rays/ Skiagrams/ Radiographs
? Radiosensitive film
? Negative- black and white
? Farther the structure ? image is magnified but borders are less sharp.
? Only 2D representation.
? For skeletal system and internal organs.
? Not much use in soft tissue injuries and abnormalities eg. tendon, ligament
etc.
Fundamental principles for radiography
? Radio-opacity
? Positioning
? Different body tissues have different
capacity to block or absorb X Rays
depending on density of structure.
Positioning
A P View
Lateral View
P A View
Radiological features of skeletal system
General features of long bone
? Compact bone-- thick , homogenous calcified
band
? Nutrient canal-- oblique radiolucent line
passing through compact bone
? Cancellous bone? network with spaces , clear
at ends of shaft.
? In young-- uncalcified epiphyseal plate-
irregular radiolucent band.
? Metaphysis? calcified epiphyseal plate and
new bone near it.
General features of Joints
? Articular disc-- not visible.
? Joint space? interval between epiphyseal areas of
adjacent bones.
Skeletal maturity
? Based on ossification centres and their fusion.
? Varies in sexes, race, geographical location and nutritional status.
Fluoroscopy
? Real time observation of moving organs.
? Image is created by striking X rays on a fluorescent screen coated with
phosphor and recorded electronically.
? High radiation exposure and low resolution of image.
Role of contrasts
? To differentiate structures of same density.
? Barium contrasts for diagnosis of abnormal constrictions and growths
of gut tube.
? Intravenous pyelogram
? Hysterosalpingography
Iodinated contrasts for
? arteriograms,
? venograms,
? myelograms.
Digital subtraction angiograms
Vascular interventions
? Peripheral vascular disease? Balloon angioplasty
? Percutaneous Transluminal Coronary Angioplasty
? Stent placement
Prevent Avascularity
? Blood clot dissolving drugs are pushed into the artery through a
catheter.
Vascular interventions
? Aneurysms- Coils, Stents
? Haemorrhage- Embolisation- eg. gelfoam
? Varicose veins :RF Ablation
? Thrombectomy ? pulmonary embolus
Non-Vascular interventions
? Drainage of pus/fluids from thorax or abdomen.
? Insert feeding tubes- gastrostomy, jejunostomy
? Uterine fibroids, heavy bleeding (DUB): PVA, glue, Gelfoam
? Renal and Gall stones fragmentation followed by drainage.
? Tumour ablation RF
? Pressure relief from cancer masses.
Computerized Axial Tomography (CT Scan)
? Principle: construction of cross sectional image by passing Xrays in multiple
directions along a 36 degree arc.
? 3mm -1cm slice
? Patient can not move
? High radiation
? Uses :
? Trauma- fractures, clots,
? Rupture of vessel in brain.
Magnetic Resonance Imaging (MRI)
? Alignment of polarised molecules in the body when placed in strong
magnetic field.
? Subjected to radio waves- alignment is displaced (depends on
chemical environment).
? When returning to aligned position the energy emitted is detected.
? Series of images is collected by computer application.
Magnetic Resonance Imaging (MRI)
? Subjected to radio waves- alignment is displaced (depends on
chemical environment).
? When returning to aligned position the energy emitted is detected.
? Series of images is collected by computer application.
Drawbacks
? Pacemakers, stents etc. contraindicated
? Patient movement degrade quality of image,
Ultrasonography
? Short bursts of high frequency
sound waves.
? Uses:
? Evaluation of organs such as
kidney, pancreas, GB, spleen etc.
? Obstetrics
? Heart
? Needle biopsy
? Drainage tube insertion
? Doppler studies
Mammography
? Parallel-plate compression
? evens out the thickness of breast tissue
? increase image quality
? reducing amount of x-rays to penetrate,
? decreasing the amount of scattered
? holding the structure to prevent motion
blur.
Positron emission tomography
(PET) scan
Some ques..
1. Ultrasonography works on principle of....
piezoelectric effect
2. X rays are electromagnetic radiation of ......... wavelength
Short
An area on a scan has an associated measurement of 900HU, it is most
likely to be composed of
A. Bone
B. Fat
C. Air
D. Water
This post was last modified on 05 April 2022