Powerpoint presentation on techniques and artifacts of bone mineral densitometry. Especial attention to hip, lumbar spine and forearm artifacts separately. Lots of real patient examples and the solutions to the technical errors. Different vendors such as Norland, Hologic, and Lunar have been discussed.

1. BONE MINERAL
DENSITOMETRY: ARTIFACTS
AND TECHNIQUES
Ramin Sadeghi
Mashhad University of Medical Sciences

2. Hip: femoral neck and total femur

3. Case 1
• A 52 y/o female patient, referred for BMD.
• What is the technical error in the hip BMD?

5. Case 1
• For total femur ROI, number of pixels below the lesser
trochanter should not be more than 10.
• The correct ROI can be found in the next image.

7. Case 2
• A 78 y/o female patient referred for BMD.
• What is the technical error of the scan.

9. Case 2
• The femoral neck ROI should not contain any bone from
other parts of the pelvis.
• Specifically, the ischium should be excluded if needed.

11. Case 3
• A young female patient referred for BMD by Norland
device.
• What is the technical error for femoral neck BMD of the
patient.

13. Case 3
• For Norland, placement of femoral neck ROI is different
from Lunar and Hologic.
• For Norland:
• The part of the neck with shortest diameter should be used.
• For Lunad and Hologic:
• The ROI should be anchored to the greater trochanter border
• Correct ROI is shown in the next slides (for the same
patient by Norland and Hologic devices.

16. Discussion
• Correct placement of femoral ROIs for Lunar, Hologic and
Norland devices as well as correct acquisition can be
found in the next figures

18. Hologic

19. Norland

20. Lunar

21. Case 4
• A 43 y/o female patient referred for BMD

24. • In case of any anatomical derangement of the left femoral
neck area, the right femur should be used.

26. Total femur
• What is called total femur on processed BMD of the hip.

28. • Total femur= Neck+Intertrochantric+Trochantric areas

29. Case 5
• What is the technical problem of the BMD in the next slide

31. • Internal rotation of the femur is of utmost importance
during acquisition.
• The lesser trochanter should not be seen or only has a
minimal protuberance.

33. Spine

34. Case 1
• A 57 y/o male patient referred for BMD.
• What is your opinion regarding the spine BMD

36. • In case of more than 1 unit difference between two
adjacent vertebrae, the vertebra with higher T-score
should be omitted.
• VFA should help elucidate the reason of the difference.

39. Case 1
• The patient had a fall from a two-story building and the
reason of T-score difference was spine fracture
• If the patient had no history of alcohol or smoking, no
history of fracture in the relatives and no evidence of
secondary osteoporosis, please calculate the risk of
fracture using Frax.
• Femoral neck BMD=0.610

40. • For history of fracture, the fracture should be
disproportionate to the trauma. Otherwise, fracture should
not be included in Frax.

42. Case 2
• A 66 y/o male patient referred for BMD.
• That is your opinion regarding the spine BMD.

44. • For spine BMD, at most two vertebrae can be omitted
from processing. If only one vertebra remains, bilateral hip
BMD should be reported.

47. Case 3
• What is your opinion regarding the next slide BMD

49. • High BMI is a major problem in BMD. Quantum dots are
the hallmarks of high BMI.

50. Case 4
• A patient with history of secondary hyperparathyroidism
due to chronic renal failure.
• What is your opinion regarding this patient.

53. • The most common causes of high BMD are degenerative
changes and osteophytes.
• However other causes of high BMD should also be
considered in proper clinical setting.
• The current case had typical renal osteodystrophy and
“Rugger Jersey” appearance of the spine.
• In this case, forearm BMD should also be taken.

55. Case 5
• A young female patient referred for BMD.
• What is your opinion regarding this BMD

57. • Metal artifacts are common in BMD.
• In this patient piercing of the belly button was the cause of
high BMD of L4

59. Case 6
• What is your opinion regarding the BMD of the next slide.

61. • A common error in spine BMD is counting the lumbar
spine up-down and using rib as landmark. In 7% of
patients T12 does not have any visible rib and can cause
error.
• Shape of L5 (like an I on its side), and L4 (like an X) are
different from the other lumbar vertebrae.
• L3 usually has the largest transvers process.
• BMD has increasing trend from L1 to L3 and decreases
from L3 to L4 (usually).
• A combination of all above-criteria should be used for
delineation of L1 to L4.

66. Case 6 another example

69. Case 7
• What is your opinion regarding the BMD of this patient

71. • Oral contrast agents can remain in the GI system for
days.
• The patient should wait at least a week before trying BMD

72. Case 8
• A 68 y/o male patient referred for BMD.
• The patient had no history of fracture, no underlying
disease, smoking or alcohol consumption.
• Please calculate the fracture risk using Frax.

76. • For fracture risk assessment using Frax, history of
fracture should be considered positive if on VFA the
patient has typical spine fracture (even without history)

77. Similar case as case 8

80. Case 9
• What is your opinion regarding the BMD of the spine in
the next slide?

83. • Aortic calcification can be seen on VFA but usually can
not change BMD and there is no need for omitting
vertebrae.

84. Case 10
• Is the processing of BMD of the next slide correct?

86. • Lumbar sib is rare but can be misleading.
• The criteria of delineation of vertebrae should be followed.

87. Case 11
• What is the technical error in the BMD of the next slide

89. • Some technical errors are very subtle.
• In this case incomplete raising of the legs resulted in
incomplete flattening of the lumbar arc.

92. Forearm

93. Case 1
• A patient with primary hyperparathyroidism.
• What is your opinion regarding the BMD of this patient

97. • Processing of forearm BMD is very sensitive and operator
dependent. Different devices have different definitions for
forearm BMD.
• The part which is used for BMD is part of the radius which
corresponds to 1/3 length of ulna (next slide)

99. • Correct ROI of the patient can be found in the next slide

101. • Forearm processing and nomenculture of different
vendors can be found in the next slides

105. Case 2
• A 47 y/o female patient with history of primary
hyperparathyroidism
• What is your opinion regarding the forearm BMD of the
patient

107. • In patient with history of coles fracture, the non-dominant
forearm should be used for BMD

109. Case 3
• A 73 y/o left handed female patient with history of primary
hyperparathyrodism.
• What is your opinion on the patient’s BMD

111. • The non-dominant forearm should not be used for BMD