Diagnostic ultrasound ( PDFDrive )

CHAPTER 23 Overview of Musculoskeletal Ultrasound Techniques and Applications 869
FIG. 23.26 Osteoarthritis. Long-axis gray-scale image of the ifth metatarsophalangeal joint demonstrates osteophyte formation (arrows) at
both sides of the joint. M, Metatarsal, P, proximal phalanx.
FIG. 23.27 Ganglion Cyst. Long-axis image of the radiocarpal joint at the radioscaphoid articulation demonstrates a lobulated, hypoechoic
ganglion cyst (arrows) arising from the region of the scapholunate ligament. Note the neck (arrowhead) arising from the joint. R, Radius, S,
scaphoid.
chondrocalcinosis in which cartilage calciication may be seen
with an intracartilaginous echogenic line. Tophi are focal crystal
accumulations, which occur around joints in some patients with
gout, appearing as clumps of hyperechoic material, which may
have a surrounding hypoechoic rim, an appearance has been
referred to as “wet sugar clumps.” 68 Bony erosions may be seen
adjacent to these tophi.
In osteoarthritis (nonerosive), cartilage thinning and
irregularity may be seen in addition to osteophytes and typically
mild synovitis (Fig. 23.26). Osteophytes appear as cortical
protrusions at the margin of the articular surface, with posterior
acoustic shadowing. 69 Synovitis may be nodular or difuse.
Joint efusions may also be demonstrated in osteoarthritis,
and although they may occur in the absence of synovitis, the
presence and size of efusion correlate with the presence of
synovitis and the extent of synovial thickening. Joint efusion
and synovitis also correlate with clinical and radiographic
disease severity. 70
SOFT TISSUE MASSES
Palpable sot tissue masses are very common and represent a
diagnostic dilemma for physicians. Although the vast majority
of these masses are benign, discrimination between benign and
malignant masses is not clinically possible. Ultrasound is a
complementary modality to MRI in the workup of sot tissue
masses. Although MRI has overall higher speciicity, several sot
tissue masses can be characterized as benign with ultrasound. 71,72
In indeterminate cases, contrast-enhanced MRI can be performed,
and this two-tiered strategy may provide an overall cost savings
to the health care system if appropriately implemented.
Ganglion cysts are mucin-illed lesions most oten found at
the wrist; they are usually closely related to a joint or tendon
sheath. Approximately 10% of ganglion cysts occur secondary
to trauma. 73 he most common location is adjacent to the
scapholunate articulation (Fig. 23.27). A neck extending from
the lesion to an underlying joint or tendon sheath should be