bone imaging

Bone Scan

Common use

Area of application

Contrast

Description

This procedure is contraindicated for

• Patients who are pregnant or suspected of being pregnant, unless the potential benefits of a procedure using radiation far outweigh the risk of radiation exposure to the fetus and mother.

Indications

• Aid in the diagnosis of benign tumors or cysts
• Aid in the diagnosis of metabolic bone diseases
• Aid in the diagnosis of osteomyelitis
• Aid in the diagnosis of primary malignant bone tumors (e.g., osteogenic sarcoma, chondrosarcoma, Ewing’s sarcoma, metastatic malignant tumors)
• Aid in the detection of traumatic or stress fractures
• Assess degenerative joint changes or acute septic arthritis
• Assess suspected child abuse
• Confirm temporomandibular joint derangement
• Detect Legg-Calvé-Perthes disease
• Determine the cause of unexplained bone or joint pain
• Evaluate the healing process following fracture, especially if an underlying bone disease is present
• Evaluate prosthetic joints for infection, loosening, dislocation, or breakage
• Evaluate tumor response to radiation or chemotherapy
• Identify appropriate site for bone biopsy, lesion excision, or débridement

Potential diagnosis

Normal findings

• No abnormalities, as indicated by homogeneous and symmetric distribution of the radionuclide throughout all skeletal structures

Abnormal findings related to

• Bone necrosis
• Degenerative arthritis
• Fracture
• Legg-Calvé-Perthes disease
• Metastatic bone neoplasm
• Osteomyelitis
• Paget’s disease
• Primary metastatic bone tumors
• Renal osteodystrophy
• Rheumatoid arthritis

Critical findings

N/A

Interfering factors

N/A

• Factors that may impair clear imaging

  • Inability of the patient to cooperate or remain still during the procedure because of age, significant pain, or mental status.
  • Metallic objects within the examination field (e.g., jewelry, earrings, and/or dental amalgams), which may inhibit organ visualization and can produce unclear images.
  • Retained barium from a previous radiological procedure may affect the image.
  • A distended bladder may obscure pelvic detail.
  • Other nuclear scans done within the previous 24 to 48 hr may alter image.

• Other considerations

  • The existence of multiple myeloma or thyroid cancer can result in a false-negative scan for bone abnormalities.
  • Improper injection of the radionuclide may allow the tracer to seep deep into the muscle tissue, producing erroneous hot spots.
  • Consultation with a health-care provider (HCP) should occur before the procedure for radiation safety concerns regarding younger patients or patients who are lactating. Pediatric & Geriatric Imaging Children and geriatric patients are at risk for receiving a higher radiation dose than necessary if settings are not adjusted for their small size. Pediatric Imaging Information on the Image Gently Campaign can be found at the Alliance for Radiation Safety in Pediatric Imaging (www.pedrad.org/associations/5364/ig/).
  • Risks associated with radiation overexposure can result from frequent x-ray or radionuclide procedures. Personnel working in the examination area should wear badges to record their level of radiation exposure.

Nursing Implications and Procedure

Pretest

• Positively identify the patient using at least two unique identifiers before providing care, treatment, or services.
• Patient Teaching: Inform the patient this procedure can assist in identification of bone disease before it can be detected with plain x-ray images.
• Obtain a history of the patient’s complaints or clinical symptoms, including a list of known allergens, especially allergies or sensitivities to latex, anesthetics, sedatives, or radionuclides.
• Obtain a history of results of the patient’s musculoskeletal systems, symptoms, and results of previously performed laboratory tests and diagnostic and surgical procedures.
• Note any recent procedures that can interfere with test results, including examinations using iodine-based contrast medium.
• Record the date of the last menstrual period and determine the possibility of pregnancy in perimenopausal women.
• Obtain a list of the patient’s current medications, including herbs, nutritional supplements, and nutraceuticals (see Effects of Natural Products on Laboratory Values online at DavisPlus).
• Review the procedure with the patient. Address concerns about pain related to the procedure and explain to the patient that some pain may be experienced during the test, or there may be moments of discomfort. Reassure the patient that the radionuclide poses no radioactive hazard and rarely produces side effects. Inform the patient the procedure is performed in a nuclear medicine department by an HCP specializing in this procedure, and takes approximately 30 to 60 min. Pediatric Considerations Preparing children for a bone scan depends on the age of the child. Encourage parents to be truthful about what the child may experience during the procedure (e.g., there may be a pinch or minor discomfort when the IV needle is inserted) and to use words that they know their child will understand. Toddlers and preschool-age children have a very short attention span, so the best time to talk about the test is right before the procedure. The child should be assured that he or she will be allowed to bring a favorite comfort item into the examination room, and if appropriate, that a parent will be with the child during the procedure. Explain the importance of remaining still while the images are taken.
• Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
• Explain that an IV line may be inserted to allow infusion of IV fluids such as normal saline, anesthetics, sedatives, radionuclides, medications used in the procedure, or emergency medications.
• Note that there are no food, fluid, or medication restrictions unless by medical direction.
• Instruct the patient to remove jewelry and other metallic objects in the area to be examined.
• Make sure a written and informed consent has been signed prior to the procedure and before administering any medications.

Intratest

• Potential complications:

• Although it is rare, there is the possibility of allergic reaction to the radionuclide. Have emergency equipment and medications readily available. If the patient has a history of allergic reactions to any substance or drug, administer ordered prophylactic steroids or antihistamines before the procedure.

• Establishing an IV site and injection of radionuclides is an invasive procedure. Complications are rare but do include bleeding from the puncture site (related to a bleeding disorder, or the effects of natural products and medications known to act as blood thinners), hematoma (related to blood leakage into the tissue following needle insertion), infection (that might occur if bacteria from the skin surface is introduced at the puncture site), or nerve injury (that might occur if the needle strikes a nerve).

• Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient.
• Ensure that the patient has removed all external metallic objects from the area to be examined prior to the procedure.
• Administer ordered prophylactic steroids or antihistamines before the procedure if the patient has a history of allergic reactions to any substance or drug.
• Avoid the use of equipment containing latex if the patient has a history of allergic reaction to latex.
• Have emergency equipment readily available.
• Instruct the patient to void prior to the procedure as a full bladder may obscure pelvic bones, and to change into the gown, robe, and foot coverings provided.
• Record baseline vital signs and assess neurological status. Protocols may vary among facilities.
• Establish an IV fluid line for the injection of saline, anesthetics, sedatives, radionuclides, or emergency medications.
• Instruct the patient to cooperate fully and to follow directions. Instruct the patient to remain still throughout the procedure because movement produces unreliable results.
• Administer sedative to a child or to an uncooperative adult, as ordered.
• Place the patient in a supine position on a flat table with foam wedges to help maintain position and immobilization.
• IV radionuclide is administered and images are taken immediately to assess blood flow to the bones.
• After a delay of 2 to 3 hr to allow the radionuclide to be taken up by the bones, multiple images are obtained over the complete skeleton. Delayed views may be taken up to 24 hr after the injection.
• The needle or catheter is removed, and a pressure dressing is applied over the puncture site.
• Observe/assess the needle/catheter insertion site for bleeding, inflammation, or hematoma formation.
• The patient may be imaged by single-photon emission computed tomography (SPECT) techniques to further clarify areas of suspicious radionuclide localization.

Post-Test

• Inform the patient that a report of the results will be made available to the requesting HCP, who will discuss the results with the patient.
• Unless contraindicated, advise patient to drink increased amounts of fluids for 24 to 48 hr to eliminate the radionuclide from the body. Inform the patient that radionuclide is eliminated from the body within 6 to 24 hr.
• No other radionuclide tests should be scheduled for 24 to 48 hr after this procedure.
• Instruct the patient to resume medication and activity as directed by the HCP.
• Observe/assess the needle/catheter insertion site for bleeding, inflammation, or hematoma formation.
• Instruct the patient in the care and assessment of the injection site.
• If a woman who is breastfeeding must have a nuclear scan, she should not breastfeed the infant until the radionuclide has been eliminated. This could take as long as 3 days. She should be instructed to express the milk and discard it during the 3-day period to prevent cessation of milk production.
• Instruct the patient to immediately flush the toilet and to meticulously wash hands with soap and water after each voiding for 24 hr after the procedure.
• Instruct all caregivers to wear gloves when discarding urine for 24 hr after the procedure. Wash gloved hands with soap and water before removing gloves. Then wash ungloved hands after the gloves are removed.
• Recognize anxiety related to test results, and be supportive of perceived loss of independent function. Discuss the implications of abnormal test results on the patient’s lifestyle. Provide teaching and information regarding the clinical implications of the test results, as appropriate. Provide contact information, if desired, for the American College of Rheumatology (www.rheumatology.org) or for the Arthritis Foundation (www.arthritis.org).
• Reinforce information given by the patient’s HCP regarding further testing, treatment, or referral to another HCP. Answer any questions or address any concerns voiced by the patient or family.
• Depending on the results of this procedure, additional testing may be needed to evaluate or monitor progression of the disease process and determine the need for a change in therapy. Evaluate test results in relation to the patient’s symptoms and other tests performed.

Related Monographs

• Related tests include antibodies, anticyclic citrullinated peptide, ANA, arthroscopy, BMD, calcium, CRP, collagen cross-linked telopeptide, CT pelvis, CT spine, culture blood, ESR, MRI musculoskeletal, MRI pelvis, osteocalcin, radiography bone, RF, synovial fluid analysis, and white blood cell scan.
• Refer to the Musculoskeletal System table at the end of the book for related tests by body system.