SKELETAL NUCLEAR MEDICINE

BONE SCAN

INDICATIONS:

1. Screen for bone metastases in patients with known or suspected cancer.
2. Infection (Osteomyelitis vs. cellulitis).
3. Evaluation of suspected fracture, including stress fractures.
4. To help determine age and metabolic activity in areas of aseptic necrosis and trauma.
5. Evaluate response to therapy, chemotherapy or radiation treatment for cancer.
6. Evaluation of prosthesis for loosening or infection.
7. Location of biopsy site.
8. Planning of radiation portals.
9. Evaluation of nonspecific bone pain.
10. Evaluation of nonspecific, abnormal roentgenographic appearance of bone.
11. Metabolic bone disease
12. Confirm the diagnosis of RSD

PATIENT PREPARATION:

Fasting is not required. Patients should be well hydrated (see "Scanning Time"). The patient will be required to lie flat and still -- if sedation or analgesia will be required, please arrange this prior to scanning.

RADIOPHARMACEUTICAL:

25 mCi of Tc-99m Methylene Diphosphonate (MDP) is injected I.V. Radiation dose is approximately 0.7 rad to bone and 0.12 rad to whole body per 25 mCi. Critical organ is the bladder; the radiation dose varies with patient hydration and voiding frequency.

SCANNING TIME:

Whole body imaging takes about 45 minutes and occurs 3 hrs after injection. Please advise your patients about the waiting period between injection and imaging.

OTHER CONSIDERATIONS:

1. No other Tc-99m imaging studies for at least 48 hours prior to scanning.
2. The triple phase bone scan includes an angiogram, blood pool images and 3 hour delayed images. For a regular bone scan only 3 hour delayed images are obtained. The indications for a triple phase bone scan include differentiating soft tissue abnormality from bony pathology (osteomyelitis vs. cellulitis), stress fractures, evaluating patients with RSD, assessing approximate age of fractures, and it may be occasionally helpful in determining benign from malignant lesions.

RATIONALE:

Bone scan visualizes a great deal of pathology long before roentgenographic changes are evident. MDP is absorbed by and subsequently bound to bone matrix. The maximum incorporation occurs during osteoblastic activity. In general, any process that results in increased osteogenic activity or increased localized osseous blood perfusion will be detected. Soft tissue processes can be differentiated from bone pathology by utilizing the triple phase technique.

BONE MARROW SCAN

INDICATIONS:

1. Evaluation of regional bone marrow abnormalities in general.
2. To identify marrow replacement by tumor.
3. To define marrow distribution.
4. To locate sites for biopsy.
5. Assessment of suspected area of avascular necrosis.
6. Diagnosis of osteomyelitis in conjunction with Labeled white blood cell imaging.

PATIENT PREPARATION:

None.

RADIOPHARMACEUTICAL:

Tc-99m labeled colloid, 8 mCi, is given I.V. Whole body radiation dose is .05 rad; liver receives 3-5 rad.

SCANNING TIME:

Imaging takes about 40 minutes and occurs about 60-90 minutes after injection.

OTHER CONSIDERATIONS/RATIONALE:

Tc-99m albumin or sulfur colloid is taken up by the reticuloendothelial cells present in bone marrow and is the basis for this imaging procedure. Particles are delivered via the blood supply; therefore, images also reflect regional blood flow.