Quality Improvement in Rad Onc Part 2

who established the mandatory programs with QA

NRC and individual states

what does NCRP stand for

national council on radiation protection and measurements

what does ICRP stand for

international commission on radiologic protection

what two organizations have many standards set for the foundation of QA

NCRP and ICRP

what professional organizations incorporate many of foundations of QA into their own standards

ACR, AAPM, ACMP

what does ACMP stand for

american college of medical physics

QA programs are _ except for NRC and state mandated components

voluntary

what does commitment to QA programs vary largely due

financial constraints

what perfect of the total billing dollars is consumed if done well

3%

what are 2 major incentives to establishing QA programs

desire to avoid lawsuits & desire to practice good radiation therapy

who has the overall responsibility for the conduct of the entire treatment process

rad onc

what is the rad onc ultimately responsible for

making sure a competent physicist is in place and actively overseeing the program

what does inadequate physics support translates into

substandard or less than optimal patient care

what are the goals of a QA program

systematic monitoring of outcomes, team approach, systematic reporting of outcomes, use of the data to facilitate improvement

what year was the first version of the blue book

1968

what is the first responsibility of the TG142

do no harm

what is the second responsibility of the TG142

make things better

what is quality control in the TG142

proving that machines, processes, and people perform as expected

what is CQI in TG142

proving that the expectation are still relevant

who does the ACR recommend that a QA committee be representative from

rad onc, physics, dosimetrist, therapist, nursing, administration, support areas

how many physicist per 400 patients treated annually should be staffed according to the blue book

1

what things does the level of involvement of physics staff varies significantly from center to center depending on

experience of physicist, experience of dosimetrist, staffing levels, level of sophistication of modalities offered

how many dosimetrist should be staffed per 300 pts annually according to the blue book

1

what does AAMD stand for

american association of medical dosimetrists

how many radiation therapist is needed per blue book in simulation

2 per every 500 pts

who has the responsibility of calibration of radiation generators or sources

medical physicist

when does acceptance testing occur

at the end of vendor’s equipment installation

what does acceptance testing verify

equipment meets specifications outlined by vendor

who performs acceptance test in accordance with the vendor’s procedure manual

vendor and physicist

what kind of equipment is the only one that is not ready for clinical use after acceptance testing is done

linacs

when is acceptance testing required

on any new equipment used in conjuction with pt treatments

what does acceptance testing test for

radiation surveys measure head leakage, area survey, interlocks, warning lights and emergency switches, rotation and accuracy of couch, gantry, and collimator

who accomplishes the commissioning

physicists

how long does commissioning take on a linac

several weeks

at the end of commissioning, what can be released for use on pts

tx planning software

what does linac commissioning result in

central axis depth-dose tables, understanding of the isodose curves for each energy, factors to be used for MU calculations

what central axis depth dose tables are created during commissioning

PDD, TMR/TPR tables

what tolerance of depths and field sizes should agree with when commissioning depth dose distributions

+- 2%

what tolerance is isodose curves when commissioning

+-2%

during commissioning what things are tested with monitor units

they can accurately deliver dose to a given energy, field size, and depth

what are the two qualities of photon beams that are necessary on external beam units

low energy and high energy

what desire of electron beams should be necessary for external beam units

6 and 20 Mev

why is electron beams 6 and 20 MeV desired to have

30% of pts will require/benefit from an electron boost or entire course of treatment

why kind of beams for linacs provide all the beams necessary for modern radiation therapy

dual energy

what can happen if a center can tx more than 30 pts per day

errors increase as work load increases & useful life of equipment may decline if there is a constant high volume

what does evidence suggest that effective treatment requires

+-5% in overall dose delivery accuracy

what three errors should QA program address for

systemic, random, human errors

what are examples of systemic errors

affects all fields of a pt or all pts

what is a random error

affects 1 field of 1 pt

what are some human errors that can happen

reading an instrument, selecting a treatment parameter, interpreting a tx plan

what are some things linac testing includes

jaw symmetry, collimator axis, light beam, mechanical and radiation isocenter, energy, field symmetry, wedge accuracy, mlc leaf position accuracy

what things are included in mechanical isocenter

collimator rotation, tx table, gantry rotation, no beam on

what things are included in radiation isocenter

collimator, tx table, gantry rotation with beam on

what should isocenter shift with couch motion up and down not exceed

+-2%

how accurate should ODI be within in linac testing

+-2mm

how accurate should field size indicators be within in linac testing

+-2mm

how accurate should gantry angle and collimator angles be within in linac testing

1 degree

how much should lasers be aligned within the isocenter in linac testing

+-2mm

what should tabletop sag with lateral or longitudinal travel under a distributed weight of 180lbs not exceed

2mm

what checks are included in QA activity with brachytherapy

source identity, source uniformity and symmetry, source calibration, applicator evaluation

what is source identity

physical length, diameter, serial number, color coding

what is source calibration

individual calibration to check source strength specified by the vendor

what is applicator evaluation

internal structure such as shielding, welding/security of device, mechanical function, etc

what two things are essential for accurate tx delivery

acceptance testing and commissioning

what 3 things does QA activities be documented

tracks equipment performance, legal record documenting, records will be reviewed by state as part of inspection

what are vendors required to do when there is a potential for safety violation

safety alerts