Imaging in osteomyelitis: Difference between revisions

From IDWiki
mNo edit summary
No edit summary
 
(6 intermediate revisions by the same user not shown)
Line 1: Line 1:
{| class="wikitable"
{|
! Technique
!Technique
! Advantages
!Advantages
! Disadvantages
!Disadvantages
! Sn/Sp
!Sn
!Sp
! Main Findings
!Main Findings
|-
|-
| X-ray
|X-ray
| Inexpensive
|Inexpensive, reproducible, and accessible
| Late diagnosis
|Late diagnosis, confusing, and radiation
| 43 to 75%/75 to 83%
|43 to 75%
|75 to 83%
| Lytic lesions, osteopenia, periosteal thickening, loss of trabecular architecture, new bone apposition
|Lytic lesions, osteopenia, periosteal thickening, loss of trabecular architecture, new bone apposition
|-
|-
|
|CT
|Excellent spatial resolution
| Reproducible
|Cost, availability, radiation exposure
| Confusing
|
|67%
|
|50%
|Blurring of fat planes, increased density of fatty marrow, periosteal reaction, cortical erosion or destruction, and sequestra, involucra, and intraosseous gas
|-
|-
|
|US
|Accessibility, inexpensive, real-time evaluation, guided aspiration/biopsy
| Accessible
|Operator dependent, cannot image across cortical bone
| Radiation
| colspan="2" |To be determined
|
|Elevated periosteum, soft tissue abscesses and fluid collections
|
|-
|-
| CT
|MRI
| Excellent spatial resolution
|Excellent spatial resolution, early detection, assesses extent of tissues affected
|Cost, availability, time requested
| Cost
|82 to 100%
| 67%/50% (chronic)
|75 to 96%
| Blurring of fat planes
|Acute: T1 shows low-signal-intensity medullary space; T2 shows high intensity surronuding inflammatory processes and edema; Gad enhances areas of necrosis<br />Subacute: evidence of Brodie's abscess, single or multiple radiolucent abscesses; T1 shows central abscess cavity with low intensity; T2 shows high intensity of granulation tissue surrounded by low-intensity band of bone sclerosis (double-line)<br />Chronic: T1 and T2 show low-intensity areas of devascularized fibrotic scarring in the marrow
|-
|-
|Bone scan
|
|Sensitive, available, relatively cheap, early detection
|
|Nonspecific, further imaging required
| Availability
|~85%
|
|~25%
| Increased density of fatty marrow
|Focal hyperperfusion or hyperemia or bone uptake
|-
|-
|Bone+WBC scan
|
|Reliable when clearly positive or negative
|
|Need for two isotopes with multiple imaging sessions over several days, higher radiation exposure, often equivocal results, long examination time (days)
| Radiation exposure
|~60%
|
|~80%
| Periosteal reaction
|Localized area of increased uptake
|-
|
|
|
|
| Cortical erosion or destruction
|-
|
|
|
|
| Sequestra, involucra, intraosseous gas
|-
| US
| Accessibility, inexpensive, real-time evaluation
| Operator dependent
| To be determined
| Elevated periosteum
|-
|
| Guided aspiration-biopsy
| US beam cannot cross cortical bone
|
| Soft tissue abscess
|-
|
|
|
|
| Fluid collection
|-
| MRI
| Excellent spatial resolution
| Cost
| 82 to 100%/75 to 96%
| Acute
|-
|
| Early detection
| Availability
|
| T1-weighted: low-signal-intensity medullary space
|-
|
| Assessment of the extent of tissue affected
| Time requested
|
| T2-weighted: high signal intensity surrounding inflammatory processes, edema
|-
|
|
|
|
| Gadolinium: enhances areas of necrosis
|-
|
|
|
|
| Subacute
|-
|
|
|
|
| Evidence of Brodie's abscess, single or multiple radiolucent abscesses
|-
|
|
|
|
| T1-weighted: central abscess cavity with low signal intensity
|-
|
|
|
|
| T2-weighted: high signal intensity of granulation tissue surrounded by low-signal-intensity band of bone sclerosis (double-line effect)
|-
|
|
|
|
| Chronic
|-
|
|
|
|
| T1- and T2-weighted: low-signal-intensity areas of devascularized fibrotic scarring in the marrow
|-
| Bone scan
| Sensitive
| Nonspecific
| ~85%/~25%
| Focal hyperperfusion
|-
|
| Availability
| Further imaging evaluation required
|
| Focal hyperemia
|-
|
| Relatively inexpensive
|
|
| Focal bone uptake
|-
|
| Early detection
|
|
|
|-
| Bone+WBC scan
| Reliable when clearly positive or negative
| Need for two isotopes with multiple imaging sessions over several days
| ~60%/~80%
| Localized area of increased uptake
|-
|
|
| High radiation exposure
|
|
|-
|
|
| Large number of equivocal results
|
|
|-
|
|
| Long examination time
|
|
|}
|}


==Specific Indications==
== Further Reading ==

*'''Post-fixation with hardware:''' WBC scan likely best, since none of the others can reliably distinguish between post-op changes and infection.
*'''Pressure ulcers:''' imaging (including MRI and WBC scan) cannot distinguish infection from bone remodeling due to pressure alone, with specificities decreasing to 15-60% range for all modalities


==Further Reading==
* Pineda C, Espinosa R, Pena A. [[10.1055/s-0029-1214160|Radiographic Imaging in Osteomyelitis: The Role of Plain Radiography, Computed Tomography, Ultrasonography, Magnetic Resonance Imaging, and Scintigraphy]]. ''Semin Plast Surg''. 2009;23(2):080-089.


*Pineda C, Espinosa R, Pena A. [https://doi.org/10.1055/s-0029-1214160 Radiographic Imaging in Osteomyelitis: The Role of Plain Radiography, Computed Tomography, Ultrasonography, Magnetic Resonance Imaging, and Scintigraphy]. ''Semin Plast Surg''. 2009;23(2):080-089.
*[https://doi.org/10.1097/00006231-200608000-00006 Nuclear medicine imaging of bone infections]. ''Nuc Med Comm''. 2006;27:633–644.


[[Category:Bone and joint infections]]
[[Category:Bone and joint infections]]

Latest revision as of 14:12, 6 October 2022

Technique Advantages Disadvantages Sn Sp Main Findings
X-ray Inexpensive, reproducible, and accessible Late diagnosis, confusing, and radiation 43 to 75% 75 to 83% Lytic lesions, osteopenia, periosteal thickening, loss of trabecular architecture, new bone apposition
CT Excellent spatial resolution Cost, availability, radiation exposure 67% 50% Blurring of fat planes, increased density of fatty marrow, periosteal reaction, cortical erosion or destruction, and sequestra, involucra, and intraosseous gas
US Accessibility, inexpensive, real-time evaluation, guided aspiration/biopsy Operator dependent, cannot image across cortical bone To be determined Elevated periosteum, soft tissue abscesses and fluid collections
MRI Excellent spatial resolution, early detection, assesses extent of tissues affected Cost, availability, time requested 82 to 100% 75 to 96% Acute: T1 shows low-signal-intensity medullary space; T2 shows high intensity surronuding inflammatory processes and edema; Gad enhances areas of necrosis
Subacute: evidence of Brodie's abscess, single or multiple radiolucent abscesses; T1 shows central abscess cavity with low intensity; T2 shows high intensity of granulation tissue surrounded by low-intensity band of bone sclerosis (double-line)
Chronic: T1 and T2 show low-intensity areas of devascularized fibrotic scarring in the marrow
Bone scan Sensitive, available, relatively cheap, early detection Nonspecific, further imaging required ~85% ~25% Focal hyperperfusion or hyperemia or bone uptake
Bone+WBC scan Reliable when clearly positive or negative Need for two isotopes with multiple imaging sessions over several days, higher radiation exposure, often equivocal results, long examination time (days) ~60% ~80% Localized area of increased uptake

Specific Indications

  • Post-fixation with hardware: WBC scan likely best, since none of the others can reliably distinguish between post-op changes and infection.
  • Pressure ulcers: imaging (including MRI and WBC scan) cannot distinguish infection from bone remodeling due to pressure alone, with specificities decreasing to 15-60% range for all modalities

Further Reading