Radiology Flashcards
Recovery of taste loss after radiotherapy occurs after
60-120 days
This force carrier particle mediate strong nuclear force that binds quarks into proton and neutrons and bind nuclie together
Gluons
Javelle water is
Sodium hypochlorite also known as daikin solution
Effective dose of panoramic radiographs
9-26 micron Sv
Photoelectric interaction in bone is ____ times greater than an equal thickness of soft tissue
6.5
Onset of radiation induced leukaemia is after
2-3years
Bystander effect is
When tissue other that focused area is affected
Atelectasis
Collapse of pulmonary alveoli
Twinning effect is seen in
NiTi
Useful range of density for a dental X-ray is
0.3-2
The beta particle emitted by a radioactive nuclie can penetrate the tissue to a maximum depth of
1.5cm
Calcifying plaque becomes 50% mineralised in
Two days
Piezo surgery was invented by
Vercellotti
Brachytherapy
Treatment of carcinomas with radiation by inserting internal implants in the body
Technique employed in radiotherapy to counteract the effect of Tumour motion due to breathing is known as
Gating
In a freshly made bleaching powder the available chlorine is
33%
Bupivacain used in concentration of
0.5%
In radiology, DNA damage cluster is defined as
Two or more double strands break within two turns of DNA
Trench ramp area are methods of
Controlled tipping
Mild hematopoetic symptoms in acute radiation syndrome is observed at dose
2-7 Gy
Multisensory communication helps these children the best
7-10yrs
Prompt somatic effects of radiation
Hair loss that occurs about 3 weeks after a dose of 400 rad to scalp
Inflammation of mucous membranes occurs
2 weeks of radiotherapy heals in 2 months after treatment has stopped
When teeth are to be removed after radiotherapy
Low concentration epinephrine containing local anaesthetic that do not contain lidocaine are used
Injury to GIT
7-15 Gy
700-1500 rads
CNS CVS symptoms
50Gy and over
Salivary flow reaches zero at
60 Gy
Deterministic and stochastic
Deterministic = mucositis Stochastic = mutagenesis, carcinogenesis, teratogenesis
Radiation induced carriers can occurs is
3 months
Mean exposure of skin from IOPA is
300mR
From OPG it’s 90mR
Occupational dose limit relative to deterministic effect to
1 lens of the eye
2 skin
1 150 micro Sv/year
2. 500 micro sievert/ year
Exposure for an IOPA with rectangular collimation, panoramic radiograph, circular collimation, CBCT, CT
Rectangular collimation 5 micro Sv Round collimation 171 micro Sv Panoramic 9-26 Cephalogram 3-6 CBCT 20-600 CT of head 860-2000
Processing solution is checked using
Reference radiograph or
STEP WEDGE PHANTOM
OR normalising solution
To differentiate margins of cyst from the surface of cortex
Low radiograph density
F speed is faster because
Presence of tubular crystal grains used in F speed
Film is off greatest diagnostic value when structure of interest has
0.6-3 optical density units
Minimum density is called gross fog or base plus fog
Optical density is 0.2-0.3
Angulation in bitewing radiograph
+7 to +10 vertical angulation
Best view for zygomatic arches
Submentovertex
Water’s view visualises
Fractures of middle third and maxillary sinus also demonstrates chronic process
For visualising condylar neck or sub condylar fractures
Reverse town and transorbital view
Submento vertex view demostrates
Base of the skull, curvature of mandible, position and orientation of condyles, and zygomatic arch fractures
For zygomatic arch fracture exposure time is reduced to 1/3 of that is used for skull visualisation
Zygoma fractures are best seen with
Water view
Best for detecting perforation in the disk
Anthrography
Radiopaque contrast in sialogram
Ethidiol ( lipid soluble)
Sianografin (non lipid soluble)
Dye in scintiscan
Tc pertechnatate is given iv
Contraindicated in acute inflammatory conditions
Principles of panoramic radiography was given by
Patero and numata
Angulation for anterior mandibular occlusal projection
-10 degrees from chin
Anterior maxillary occlusal projection
+45 through tip of the nose
Articular disk using MRI using T1 and T2
T1 or proton weighted images best demonstrate osseous and diskal tissues
T2 weighted images demonstrate inflammation and temporomandibular joint
MRI can detect accumulation of fluid in joint spaces which appears as high signal in the joint spaces in T2 images
In fluoroscopy contrast material contains
Iodine
Bimolar technique or gardener technique
Lateral oblique view of right and left half of jaw
Best suited for detecting calculus in submandibular gland
Mandibular true occlusal
