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Shrinkage revisited: how long is long enough?
Ann P Murchison1, Jurij R Bilyk, Ralph C Eagle
1Wills Eye Emergency Room, Wills Eye Institute, Philadelphia, Pennsylvania 19107, USA. amurchison@willseye.org
Ophthalmic Plastic and Reconstructive Surgery
|May 24, 2012
Summary
Temporal artery biopsy (TAB) specimens shrink significantly after fixation. To achieve the standard 20 mm length, surgeons must account for the average 4.61 mm shrinkage during giant cell arteritis diagnosis.
Area of Science:
- Vascular Surgery
- Pathology
- Rheumatology
Background:
- Temporal artery biopsy (TAB) is the gold standard for diagnosing giant cell arteritis (GCA).
- A postfixation specimen length of 20 mm is commonly accepted as adequate for diagnosis.
- Mean specimen shrinkage of 2.4 mm is reported, but correlation with diagnostic outcomes is lacking.
Purpose of the Study:
- To quantify specimen shrinkage in temporal artery biopsies (TABs).
- To determine if TAB specimen shrinkage correlates with biopsy results, patient demographics, or surgeon.
- To inform surgical practice regarding specimen length for accurate GCA diagnosis.
Main Methods:
- Prospective study of patients undergoing TAB over one year.
- Recording pre- and postfixation measurements of TAB specimens.
- Statistical analysis to correlate shrinkage with biopsy results, age, gender, and race/ethnicity.
Main Results:
- Mean TAB specimen shrinkage was 4.61 mm ± 2.97.
- No significant difference in shrinkage between positive and negative GCA biopsy results (p=0.43).
- Shrinkage did not correlate with specimen length, fixation duration, surgeon, patient gender, or race/ethnicity.
Conclusions:
- TAB specimens exhibit significant mean shrinkage of 4.61 mm.
- To achieve the 20 mm postfixation length, specimens of approximately 27.58 mm should be obtained.
- Factors like surgeon, patient demographics, and biopsy results do not significantly impact TAB specimen shrinkage.
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