MRSC2200: QA & ICRU

Which organisation defines QA as procedures ensuring the consistency of medical prescriptions and their safe fulfilment?

WHO

According to the WHO, which of the following is NOT one of the four key components of QA?

Cost-Benefit Analysis

The GTV is defined as?

The visible, palpable, or demonstrable extent of malignant disease

Which volume is the true disease extent & considered the “pure” clinical concept?

CTV

The PTV is a geometrical concept used to account for…

Both internal movement and setup error

According to ICRU 50/62, the recommended variation of dose across the PTV is:

+7% to -5%

What is the definition of the Conformity Index (CI)?

The quotient of Treated Volume and the PTV

In plan evaluation, "Visual Inspection" primarily involves…

Looking at the isodose distribution and ensuring all relevant lines are on

A "Serial Organ" is one where…

Exceeding dose limits to even a small portion can cause entire loss of function

The ICRU Reference Point should ideally be located…

At the center of the PTV and, when possible, at the intersection of beam axes

Which category of error is described as "rare but catastrophic events with severe patient harm"?

Major Systematic Failures

What could be classified as a primary technical failure?

Multileaf collimators (MLCs) not moving properly during IMRT delivery

In the ISBAR framework, what does the "A" stand for?

Assessment

Approximately what percentage of health-related incidents occur due to poor communication?

80%

The London Protocol categorises contributory factors into how many classes?

6

Which factor is NOT part of the London Protocol's contributory factors?

Financial Profitability

The "Swiss Cheese Model" of error prevention refers to…

Stacking multiple layers of defense to prevent an error from penetrating

What is a "Near Miss"?

An incident that almost occurred but was caught before reaching the patient

Standard Clinical Procedures (SCPs) should…

Be updated regularly based on new evidence and incident analysis

A "Just Culture" in healthcare focuses on…

Balancing accountability with understanding system contributions

In plan evaluation, what is the consequence of using an isodose margin that is too large around the PTV?

It treats too much healthy tissue and increases side effects

Why is it problematic to have parallel wedges with opposing angles?

One wedge pushes the dose anteriorly while the other pushes it posteriorly, defeating the purpose.

In a 3DCRT plan, uneven weighting on fields opposing each other will result in…

Uneven dose distribution

What is a "Parallel Organ"?

An organ where functional units act independently

The "Treated Volume" is generally aimed to be the:

95% isodose line

Which dose reporting level is used for basic palliative cases where no PTV is contoured?

Level 1

Why are errors in radiotherapy particularly concerning compared to other medical fields?

Their repetitive nature, delayed manifestation, and cumulative impact

Situational awareness in RT means…

Maintaining consciousness of environmental factors and potential hazards

Who is responsible for QA?

Everyone in the department

What happens if an OAR is not contoured correctly?

The DVH readings for that organ will be inaccurate

Which framework transforms clinical information into clear, actionable communication?

ISBAR

QA is concerned only with the treatment delivery phase of the patient pathway.

False

The Internal Target Volume (ITV) is CTV + the internal margin (IM).

True

Standard healthcare reporting systems are perfectly designed for the technical complexities of radiation oncology.

False

Human factors, such as fatigue and complacency, are considered the "weakest link" in the radiotherapy treatment chain.

True

A 6MV beam has greater penetrating power than an 18MV beam.

False

Peer review rounds are only useful for junior radiation oncologists.

False

What does the acronym ICRU stand for?

International Commission on Radiation Units & Measurements

In the clinical communication framework, what does the acronym ISBAR stand for?

Identify, Situation, Background, Assessment, Recommendation