Diagnostic ultrasound ( PDFDrive )

910 PART III Small Parts, Carotid Artery, and Peripheral Vessel Sonography
A
B
C
FIG. 25.22 Ultrasound-Guided Aspiration of
Paralabral Cyst in the Hip. A 54-year-old woman with
left hip pain. (A) Sagittal luid–sensitive image of the
hip showing a multiloculated paralabral cyst (arrow)
associated with a tear of the anterior superior labrum
(not shown). (B) The same cyst (arrow) shown on
ultrasound as a septated hypoechoic collection overlying
the anterior joint margin. The acetabulum (a), femoral
head (fh), and labrum (L) are labeled. (C) Ultrasoundguided
aspiration of the cyst is depicted. A 22-gauge
spinal needle (N) is positioned within the cyst (c) for
purposes of aspiration and injection. The needle tip is
depicted (arrow).
measures. 41 Likewise, autologous blood injections and PRP
injections have been successfully used in both the elbow and
the knee 42-44 (Figs. 25.25 and 25.26, Video 25.5). he advantage
of performing these injections under ultrasound guidance
becomes evident when the clinician wants to generalize such
techniques to include tendons close to neurovascular structures,
such as the hamstring tendon origin. Newer technology is now
available that allows sonographically directed emulsiication of
focal tendinosis, calciications, and enthesopathic spurs followed
by removal during the course of the procedure. 46 he technique
employs a coaxial system with a mechanically active hollow tip
that disrupts the tissue and is connected to vacuum suction,
while the outer tube supplies sterile water to cool the tip and
remove debris as part of the suctioned material (Fig. 25.27, Video
25.6). his technique is relatively new, and no deinitive long-term
trials are available to assess eicacy, but preliminary results appear
promising.
PERINEURAL INJECTIONS
Ultrasound has shown promise in evaluating and treating patients
with painful lesions of peripheral nerves due to compressive
neuropathies, such as in carpal or cubital tunnel syndromes, or
in cases of posttraumatic or postsurgical neuromas. 35 hese
injections can include nerve blocks with long-acting anesthetic,
therapeutic injections using an injectable steroid, or neurolytic
therapy with an agent that promotes cellular death such as absolute
ethanol. 47,48 A rapidly absorbed injectable steroid, such as dexamethasone,
may be preferable for supericial lesion to minimize
potential complications, such as depigmentation or atrophy of
the subcutaneous fat.
A thorough knowledge of the normal sonographic appearances
of nerves and their anatomic course is a prerequisite. 35,36 In the
case of small sensory nerves, which can be diicult to visualize,
knowledge of the anatomic relationships of the nerves to adjacent