Chapter 6 – Skeletal System Scintigraphy

Which of the following is a malignant bone disease?

Ewing’s sarcoma

A three-phase bone scan is often done to differentiate:

Osteomyelitis vs. cellulitis

The presence of gastric and thyroid activity on a bone scan signals:

Free pertechnetate

Purpose of a reducing agent in a Tc-99m diphosphonate kit:

Both

What is the dose of Tc-99m MDP most often prescribed for a planar bone scan?

20-30 mCi

Which of the following is least likely to cause an artifact on a bone scan:

Colostomy bag

What is not an indication for a bone scan?

Osteoporosis

The presence of free pertechnetate on a bone scan may be the result of:

Both

What is the purpose of hydration and voiding after an injection for a bone scan?

Reduce radiation dose to the bladder

Cause of generalized diffuse abdominal activity:

Malignant ascites

Timing protocol best describing a four-phase bone scan:

During injection, immediately following, 2–4 h and 18–24 h

A focal hot spot near the left femur shows up on a bone scan. What is/are the best way/ways to proceed?

Both

A bone scan showing relatively uniformly increased skeletal uptake of radiopharmaceutical with almost absent renal and bladder activity is usually referred to as a:

Superscan

The glove phenomenon is usually the result of:

Arterial injection

What are common sites of bony metastasis?

All of the above

Purpose of stannous ion in a diphosphonate kit:

Acts as a reducing agent

The appendicular skeleton includes the following bones, except:

Skull

The axial skeleton contains:

All of the above

By what mechanism do diphosphonates localize in the bone?

Ion exchange

Which of the following describes a pediatric bone scan?

Increased uptake along epiphyseal plates

The first phase of a three-phase bone scan is best performed by:

Bolus injection + dynamic 2-s images for 60 s

What pharmaceuticals may be used for bone marrow imaging:

Both 

What is often used in imaging-suspected avascular necrosis of the hip?

Pinhole collimation (also SPECT)

Splenic uptake on a bone scan is often associated with

Sickle cell disease

The bone is made of:

Hydroxyapatite + collagen

Osteoblastic activity refers to:

New bone formation

Osteoclastic activity refers to:

Destruction and reabsorption of bone

Function of the skeleton:

All of the above

Which group shows the highest rate of primary bone tumors?

Children

The radiation dose from a bone scan is highest to the:

Bladder

When performing a bolus injection for a three-phase bone scan, why would the tourniquet be released and injection delayed for 1 min?

Reduce transient hyperemia

What is an advantage of spot planar imaging over whole body imaging for a bone scan?

Decreased patient-to-detector distance

Reason not to inject in right antecubital fossa:

Suspicion of osseous abnormality there

The preparation for a bone scan is:

None of the above

Metastases usually affect the axial skeleton before the appendicular skeleton.

True

The advantage(s) of bone scanning over plain radiography is:

All of the above

The mechanism of localization for bone marrow scanning is:

Phagocytosis

A large amount of diffuse soft tissue activity present on a bone scan at 4 h frequently represents:

Renal insufficiency

What imaging agent can be used to image the skeleton as well as myocardial infarction?

Tc-99m PYP

Rib fractures often show up as:

Multiple focal hot spots located in consecutive ribs

Cold defect in left proximal humerus is most likely from:

Surgically implanted metal