What type of radiation is primarily used in PET scans?

Gamma (γ) rays

Riddle: I am a negatively charged electrode in an X-ray tube, where electrons are emitted. What am I?

Cathode

True or False: The photoelectric effect contributes to 80% of X-ray production in most tubes.

False. The Bremsstrahlung reaction accounts for 80% of X-ray production in most tubes.

The unit of measurement for absorbed dose in radiation is the ______.

Gray (Gy)

Which of the following is a deterministic effect of radiation? A) Genetic mutations B) Skin erythema C) Cancer D) Teratogenicity

B) Skin erythema

What is the primary purpose of a collimator in X-ray imaging?

To limit scattered radiation and direct the X-ray beam

Fill in the blank: The ______ principle states that radiation exposure should be kept as low as reasonably achievable.

ALARA

True or False: CT scans use ionizing radiation and are considered safe for pregnant women.

False. CT scans use ionizing radiation, which poses risks during pregnancy.

What material is commonly used for filters in X-ray tubes?

Aluminum

Riddle: I am an imaging technique that uses sound waves and is non-invasive. What am I?

Ultrasound (USG)

Which imaging modality is best for assessing the presence of gallstones?

Ultrasound (USG)

Fill in the blank: The standard distance for most radiography is ______.

100 cm

What is the significance of the 10-day rule in radiology?

To avoid radiation exposure to an undiagnosed pregnancy

True or False: The effective dose accounts for the varying sensitivity of tissues to radiation.

True

Which type of CT scan technology allows for continuous rotation of the X-ray unit?

Slip-ring technology

Riddle: I am used to visualize blood flow and can show the direction of flow. What am I?

Doppler ultrasound

What is the term for the biological effect of radiation that occurs without a dose threshold?

Stochastic effects

Fill in the blank: The ______ reaction involves the interaction of electrons with the nucleus, contributing to X-ray production.

Bremsstrahlung

Which imaging modality uses gadolinium as a contrast agent?

MRI

True or False: Digital radiography uses film to capture images.

False. Digital radiography uses electronic sensors to capture images.

What is the main advantage of using dual-source CT technology?

Better temporal resolution and ability to scan at any heart rate

Fill in the blank: The ______ effect relates to the increased brightness beyond objects that transmit many sound waves in ultrasound.

Posterior Acoustic Enhancement

Which imaging technique is preferred for assessing acute ischemic infarcts?

Diffusion-Weighted MRI (DWI)

Riddle: I am the standard for assessing tissue response to stress and can help differentiate lesions. What am I?

Elastography

What is the primary method used in MRI to visualize soft tissue structures?

Nuclear magnetic resonance

True or False: Non-ionic contrast media are preferred for myelography due to lower risk of complications.

True

Fill in the blank: The ______ unit measures the radiation dose output in CT scans.

CTDI (CT Dose Index)

Which contrast agent poses the greatest risk of nephrogenic systemic fibrosis (NSF)?

Gadodiamide

Which imaging modality is the least expensive and does not use ionizing radiation?

Ultrasound (USG)

Fill in the blank: The ______ classification system is used for categorizing mammography lesions.

BIRADS