Campbell et al reported a ALVAL (Aseptic Lymphocytic Vasculitis-Associated Lesion) histologic score to describe microscopic findings associated with a metal-on-metal joint prosthesis. The authors are from the UCLA Orthopedic Hospital in Los Angeles.
Paramters:
(1) appearance of the synovial lining
(2) nature of the inflammatory cell infiltrate
(3) tissue arrangement
|
Parameter |
Finding |
Points |
|
appearance of the synovial lining |
intact |
0 |
|
|
focal loss of synovial surface; fibrin may be present |
1 |
|
|
moderate to marked loss of synovial surface; fibrin present |
2 |
|
|
complete loss of synovium; abundant fibrin and/or necrosis |
3 |
|
inflammatory cell infiltrate |
none or minimal |
0 |
|
|
predominantly macrophages with occasional lymphocytes |
1 |
|
|
mixture of macrophages and lymphocytes, may be diffuse or show small perivascular aggregates |
2 |
|
|
mixture of macrophages and lymphocytes, with large perivascular aggregates |
3 |
|
|
lymphocytes predominate, may have multiple large perivascular aggregates, may show follicles |
4 |
|
tissue arrangement |
normal |
0 |
|
|
small areas of synovial hyperplasia; focal necrosis may be present |
1 |
|
|
little normal tissue; distinct cellular and acellular zones; thick fibrous layers may be present |
2 |
|
|
perivascular lymphocytic aggregates; thick acellular areas may be present |
3 |
where:
• A perivascular aggregate was designated small if it occupied less than half of a high power field and large if it occupied more than of a high power field.
total score =
= SUM(points for all 3 parameters)
Interpretation:
• minimum score: 0
• maximum score: 10
• A patient with ALVAL tended to have a higher score.
|
Score |
Level |
|
0 to 4 |
low |
|
5 to 8 |
intermediate |
|
9 or 10 |
high |
Purpose: To evaluate tissue adjacent to a metal-on-metal joint prosthesis using the ALVAL score of Campbell et al.
Specialty: Surgery, orthopedic
Objective: other testing
ICD-10: T84.5,
