DEXA SCANS UPDATED ACTUAL QUESTIONS AND
CORRECT ANSWERS
Question:
1. Bone densitometry (DEXA scans)
Answer:
used to diagnose and monitor osteopenia and osteoporosis
Question:
2. Indications
Answer:
Premenopausal oophorectomy (estrogen deficiency) Plain films suggestive of osteopenia Endocrinopathies
associated with osteopenia
- Hyperparathyroidism
- Prolactinoma
- Cushing syndrome
- Male hypogonadism
- Hyperthyroidism
unexplained or multiple bone fractures anorexia multiple myeloma prolonged immobility GI
malabsorption (proteins and calcium deficiency) Chronic renal disease Treatment-related (breast cancer
anti hormone therapy, long-term heparin, steroids) Monitoring treatment of osteoporosis Onset of
menopause
Question:
3. Osteopenia and osteoporosis
Answer:
Most commonly seen in postmenopausal women
MOST COMMON fractures
- Vertebral compression fractures
- Hip fractures
20% of patients >40 y/o die within 1 year following hip or vertebral fracture
Treatment is most effective if found early
Question:
4. DEXA scans recommended for:
Answer:
Postmenopausal women with at least one additional risk factor (FH, Caucasian, thin) All women >65 y/o
Women on long-term Hormone Replacement Therapy (HRT) Men or women
- With hyperparathyroidism
- On long-term glucocorticoid therapy
- Being monitored on treatment for osteoporosis
Question:
5. What bones to study
, Answer:
Lumbar vertebrae best calcellous bone to study Radius best cortical bone to study Proximal hip (neck of
femur) best mixed calcellous and cortical bone Other sites if symptomatic
Question:
6. Measuring bone mineral density (BMD)
Answer:
Dual Energy X-ray Absorptiometry (DEXA)
Dual photon source measures density of bone
- Two different X-ray energies produce dual photons
- More energy is produced, so bones are more easily penetrated
Question:
7. When to measure the radius
Answer:
Patient weight exceeds limit of table
Severe arthritic changes affect the axial skeleton
Question:
8. Reporting bone density
Answer:
Reported in terms of deviation from mean values
- T scores compare the patient's results with those of a group of young, healthy adults
- Z scores compare patient's results with those of a group of age-matched controls
T scores are probably more accurate in predicting fracture risk
Question:
9. Osteopenia (WHO definition)
Answer:
bone density value > 1 standard deviation (SD) below peak bone mass levels in your women
Question:
10. Osteoporosis (WHO definition)
Answer:
bone density > 2.5 SDs below same scale
Question:
11. Fracture risk assessment tool (FRAX)
Answer:
Age Gender Weight & height Previous fracture smoking Family history of hip fracture Glucocorticoid use
(eg, Prednisone) Rheumatoid arthritis Femoral neck bone mineral density
Question:
12. 10 year probability
Answer:
CORRECT ANSWERS
Question:
1. Bone densitometry (DEXA scans)
Answer:
used to diagnose and monitor osteopenia and osteoporosis
Question:
2. Indications
Answer:
Premenopausal oophorectomy (estrogen deficiency) Plain films suggestive of osteopenia Endocrinopathies
associated with osteopenia
- Hyperparathyroidism
- Prolactinoma
- Cushing syndrome
- Male hypogonadism
- Hyperthyroidism
unexplained or multiple bone fractures anorexia multiple myeloma prolonged immobility GI
malabsorption (proteins and calcium deficiency) Chronic renal disease Treatment-related (breast cancer
anti hormone therapy, long-term heparin, steroids) Monitoring treatment of osteoporosis Onset of
menopause
Question:
3. Osteopenia and osteoporosis
Answer:
Most commonly seen in postmenopausal women
MOST COMMON fractures
- Vertebral compression fractures
- Hip fractures
20% of patients >40 y/o die within 1 year following hip or vertebral fracture
Treatment is most effective if found early
Question:
4. DEXA scans recommended for:
Answer:
Postmenopausal women with at least one additional risk factor (FH, Caucasian, thin) All women >65 y/o
Women on long-term Hormone Replacement Therapy (HRT) Men or women
- With hyperparathyroidism
- On long-term glucocorticoid therapy
- Being monitored on treatment for osteoporosis
Question:
5. What bones to study
, Answer:
Lumbar vertebrae best calcellous bone to study Radius best cortical bone to study Proximal hip (neck of
femur) best mixed calcellous and cortical bone Other sites if symptomatic
Question:
6. Measuring bone mineral density (BMD)
Answer:
Dual Energy X-ray Absorptiometry (DEXA)
Dual photon source measures density of bone
- Two different X-ray energies produce dual photons
- More energy is produced, so bones are more easily penetrated
Question:
7. When to measure the radius
Answer:
Patient weight exceeds limit of table
Severe arthritic changes affect the axial skeleton
Question:
8. Reporting bone density
Answer:
Reported in terms of deviation from mean values
- T scores compare the patient's results with those of a group of young, healthy adults
- Z scores compare patient's results with those of a group of age-matched controls
T scores are probably more accurate in predicting fracture risk
Question:
9. Osteopenia (WHO definition)
Answer:
bone density value > 1 standard deviation (SD) below peak bone mass levels in your women
Question:
10. Osteoporosis (WHO definition)
Answer:
bone density > 2.5 SDs below same scale
Question:
11. Fracture risk assessment tool (FRAX)
Answer:
Age Gender Weight & height Previous fracture smoking Family history of hip fracture Glucocorticoid use
(eg, Prednisone) Rheumatoid arthritis Femoral neck bone mineral density
Question:
12. 10 year probability
Answer:
