Diagnostic ultrasound ( PDFDrive )

912 PART III Small Parts, Carotid Artery, and Peripheral Vessel Sonography
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me
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N
A
C
FIG. 25.25 Ultrasound-Guided Injection of Autologous Blood to Induce Healing Response. (A) Coronal inversion-recovery magnetic resonance
imaging scan of the affected elbow in a 43-year-old man with medial epicondylitis shows increased signal intensity (arrow) of the common lexor
tendon mass and adjacent collateral ligament. (B) Long-axis ultrasound image of the tendon (T) and adjacent medial epicondyle (me) shows
that tendon is predominantly hypoechoic, relecting underlying tendinosis. (C) Image shows 22-gauge needle (N) placed within the common lexor
tendon mass, for purposes of mechanical fenestration, and injection of 5 mL of autologous blood, obtained from an antecubital vein. Tendon
echogenicity (small arrow) is increased by microbubbles within the injected blood.
me
FIG. 25.26 Baseline Image Before Autologous Blood Injection.
Common extensor tendon mass (T) in 50-year-old woman with partial
tear of the deep portion of the tendon (short arrow, extensor carpi
radialis brevis) as it inserts on the medial epicondyle (me); rc, radiocapitellar
joint; long arrow, plane of needle entry for percutaneous tenotomy and
autologous blood injection. See also Video 25.5.
anatomic compartments is of value. Nerves are best visualized
in short axis as clusters of hypoechoic fascicles with echogenic
septations (internal epineurium), which have a surrounding
echogenic epineurial sleeve (external epineurium). An enlarged
hypoechoic nerve may indicate neuritis, whereas a focal
hypoechoic nodule seen in relationship to the nerve may represent
a neuroma in the appropriate clinical setting.
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rc
Ultrasound allows direct targeting of the perineural sot tissue
or a neuroma for injection (Fig. 25.28, Video 25.7). he nerve
is best approached in short axis, usually with a 1.5-inch 25-gauge
needle or occasionally a spinal needle. In the case of a perineural
injection, it is helpful to position the needle in close proximity
to the nerve, injecting small amounts of anesthetic until a clear-cut
luid plane outlining the epineurium is evident. When this is
achieved, the therapeutic mixture can be instilled. he same
procedure is used when performing ultrasound-guided neurolytic
therapy. I typically inject a mixture of long-acting anesthetic
(0.75% bupivacaine) with a total of 0.5 to 1 mL of absolute ethanol
for peripheral nerve lesions. In my experience, absolute ethanol
may require multiple injections and can produce a marked
postinjection inlammatory response that can last for several
days. he volume injected can be variable and in general does
not exceed 1 mL. Multiple small injections have been advocated
to be eicacious for Morton neuromas (0.25-0.5 mL).
CONCLUSION
Ultrasound ofers distinct advantages in providing guidance for
delivery of therapeutic injections. Most important, ultrasound
allows the operator to visualize the needle and make adjustments
in real time, to ensure that medication is delivered to the appropriate
location. Current ultrasound technology provides excellent
depiction of relevant musculoskeletal anatomy. he needle has
a unique sonographic appearance and can be monitored with