Dental CT Scan Parameter Form
... IAC Dental CT Scan Parameter Form
This form must contain specific information for the Dental CT case study submitted for review.
Patient initials (first 3 letters of last name, first 3 letters of first name) or ID (MRN):
Cone beam CT unit make and model:
Dental CT scanners and physical quality parameters El
... Results: Scanora 3D, with less radiation time, showed less dosing values compared to 3D Accuitomo
80 (Mean 0.33 mSv, SD ± 0.16 VS 0.18 mSv, SD ± 0.1). Using paired t-test, no significant difference
was found in Accuitomo two scan sessions (p > 0.05), while it was highly significant in Scanora (p >
Chapter 10, (6th ed)
... Reduction of repeats
Windowing and leveling allow for less images being produced.
Image ingtensifier, 5 minute timer, dead man switch, filter on fluoro tube, lead in table to protect Rad.
Last image hold
Protocols that reduce dose
THERE IS GREAT INTEREST IN DOSE REDUCTION IN ...
... (p=0.549). The CTDIvol in both RP-CT and DG#CT CTDIvol increase with higher BMI,
but the dependence is much stronger in the DG-CT studies than in the RP-CT (DG-CT
r=0.852,p<0.001; RP-CT r=0.279,p=0.044). Variations in CTDIvol with BMI indicates the
ability of the CT system to modulate the mA accordi ...
Purpose: Emission guided radiation therapy (EGRT
... Purpose: Emission guided radiation therapy (EGRT) is a new concept that allows for online
biological targeting with radioactive tracers. The concept was previously demonstrated in
phantom experiments involving free breathing trajectories. This study involves the first patient
imaging data to assess ...
X-ray fluoroscopy imaging in the invasive cardiac laboratory
... increased patient dose rate for flat panel fluoroscopy systems?
a) The size of the output phosphor is constant.
b) Decreasing minifaction gain requires increase tube output.
c) Detector target dose remains constant for all FOV.
d) As the FOV gets smaller, local photon density increases.
e) Use of se ...
All patients will receive both EBRT and BT. Summation of EBRT and
... All patients will receive both EBRT and BT. Summation of EBRT and BT doses will be
performed by calculation of a biologically equivalent dose in 2 Gy per fraction (EQD2) using
the linear quadratic model with α/β = 10 Gy for tumour effects and α/β=3 Gy for late normal
tissue damage.The repair half ti ...
Radiation Dose Reduction in Pediatric CT
... implementing radiation dose reduction.
• To become familiar with the various modifications that can
be done to reduce neuroradiological CT examination
radiation doses in pediatrics (on both older and newer
pp003 calculation of conversion factor relating measured patient
... profile, to measure entrance surface dose (ESD), and the peak
surface dose (PSD).
The objective of this work was to study the feasibility of using RF
as in vivo dosimeters to measure ESD from patients undergoing
routine CT examination of the sinus and relate the
measurements to the scanner calculate ...
II. Basic Physics of Ionizing Radiation
... intended to reflect the total biological
effect of a given exposure on a human. It
is a weighted average of the individual
doses to a number of important tissues:
PDF version - Sciencesconf.org
... Université Pierre et Marie Curie - Paris 6 - UFR de Médecine Pierre et Marie Curie (UPMC) –
Université Pierre et Marie Curie (UPMC) - Paris VI – 4 place Jussieu - 75005 Paris, France
... • The weighting factor (wR) is also 1 for X-rays and
• The weighting factor (wR) is 20 for alpha particles
and 5-20 for neutrons, depending on energy.
• Some beta particles may not be much hazard because
they have low energy and will not penetrate the skin
(for example, from tritium).
... • Positioning can be more critical, aligning to detectors
• Manual techniques may be required to produce
• Post processing as a method of enhancing image
should be discouraged
• Exposure creep must be avoided (any more than 4%
ADVANTAGE provides statistical evidence of ...
... HSS ensures that its leading Radiology Information
System – CRIS – remains the most functionally rich
system available by continually investing in research
and development. As the market’s leading RIS provider,
HSS works closely with many PACS suppliers and niche solution providers. While HSS is exp ...
Introduction to Radiation Physics, Quantities and Units
... electromagnetic and particulate forms of
• Understand the distinctions between the units
of radiation quantity, exposure and dose.
• Be familiar with some of the methods used to
measure radiation dose.
CT Dose Measures
... radiation dose is being absorbed and
radiosensitivity of the tissue irradiated
• Estimates the equivalent whole-body dose from
the absorbed dose
• ED allows estimate of stochastic risks (cancer
induction) (BIER report)
• Unit is the Sievert (Sv)
Radiation Dose in Interventional Radiology PDF
... cancer. Risk of stochastic radiation effects depends upon many
• Demographic indices (patient age, patient gender and patient
• Patient medical history (prior x-ray exams).
Deterministic Effects are short-term effects observed in the
portion of the patient’s body receiving ...
Slice Wars vs Dose Wars in Multiple
... force behind the slice wars. However, the increasing number of
slices and the increasing complexity
in the performance of cardiac CT
imaging has led to the development
of protocols that can yield high radiation dose (expressed in terms
of “effective dose”). In general, the
demand for shorter scan ti ...
Accounting for Imaging Dose: Impact of California Regulation
... • Annual verification of the CT dose displayed by scanner
Section 2 (effective July 1, 2013)
Mandatory CT accreditation
Section 3 (effective Jan 1, 2011, SB 38 July 1, 2012)
• Report CT over-exposures exceeding certain dose limits
• Report CT or RT over-doses to fetus or incorrect site, etc
The sievert (symbol: Sv) is a derived unit of ionizing radiation dose in the International System of Units (SI). It is a measure of the health effect of low levels of ionizing radiation on the human body.Quantities that are measured in sieverts are intended to represent the stochastic health risk, which for radiation dose assessment is defined as the probability of cancer induction and genetic damage.The sievert is used for radiation dose quantities such as equivalent dose, effective dose, and committed dose. It is used both to represent the risk of the effect of external radiation from sources outside the body, and the effect of internal irradiation due to inhaled or ingested radioactive substances.Conventionally the sievert is not used for high dose rates of radiation which produce deterministic effects, which is the severity of acute tissue damage which is certain to happen. These effects are compared to the physical quantity absorbed dose measured by the unit gray (Gy).To enable consideration of stochastic health risk, calculations are performed to convert the physical quantity absorbed dose into equivalent and effective doses, the details of which depend on the radiation type and biological context. For applications in radiation protection and dosimetry assessment the International Commission on Radiological Protection (ICRP) and International Commission on Radiation Units and Measurements (ICRU) have published recommendations and data which are used to calculate these.The sievert is of fundamental importance in dosimetry and radiation protection, and is named after Rolf Maximilian Sievert, a Swedish medical physicist renowned for work on radiation dosage measurement and research into the biological effects of radiation. One sievert carries with it a 5.5% chance of eventually developing cancer.One sievert equals 100 rem. The rem is an older, non-SI unit of measurement.To enable a comprehensive view of the sievert this article deals with the definition of the sievert as an SI unit, summarises the recommendations of the ICRU and ICRP on how the sievert is calculated, includes a guide to the effects of ionizing radiation as measured in sieverts, and gives examples of approximate figures of dose uptake in certain situations.