Page 459 - Adams and Stashak's Lameness in Horses, 7th Edition

Diagnostic Imaging 425

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A B
Figure 3.250. Dorsal proton density image with fat saturation in the medial femoral condyle and the axial margin of the medial
(A) and dorsal short tau inversion recovery (STIR) image (B) of the tibial plateau suggestive of abnormal bone fluid (black arrows).
left stifle of a horse with a tear of the cranial horn of the medial Source: Courtesy of Dr. Carter Judy.
meniscus (white arrow). There is intraosseous signal hyperintensity

Moreover, the cranial cruciate ligament is supposed to Cartilage Lesions
be heavily subjected to magic angle artifact in closed Cartilage erosions are readily visible in the stifle
high‐field magnets with the patient in lateral recum­ thanks to the innately thicker cartilage than in distal limb
87
bency. Magic angle effect was also consistently seen in joints. Focal cartilage erosions are more easily recognized
the cranial cruciate ligament with the horse in dorsal than generalized thinning of degenerative cartilage.
recumbency and the stifle positioned in extension in an Invariably cartilage erosions are accompanied by an
open low‐field 0.25‐T magnet. Therefore, the internal increase in subchondral fluid and STIR signal intensity. 87
signal of the ligament should never be assessed on T1
images only, but evaluation should also include short
87
TE sequences. Thickening of the cranial cruciate liga­ References
ment with internal signal changes in T1 and PD images
has been described as the most consistent finding in cra­ 1. Aarsvold S, Solano M, Garcia‐Lopez J. Magnetic resonance imag­
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