AJR 2002; 179:109-112
© American Roentgen Ray Society
Using a Coaxial Technique with a Curved Inner Needle for CT-Guided Fine-Needle Aspiration Biopsy
Sanjay Gupta1,
Kamran Ahrar,
Frank A. Morello, Jr.,
Michael J. Wallace,
David C. Madoff and
Marshall E. Hicks
1 All authors: Department of Radiology, Vascular and Interventional Radiology
Section, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe
Blvd., Box 325, Houston, TX 77030-4009.
Received November 26, 2001;
accepted after revision January 4, 2002.
Address correspondence to S. Gupta.
Introduction
Percutaneous needle biopsy is a safe and effective technique for obtaining
tissue from various regions in the body for diagnosis. Although the shortest
path between the skin and the target lesion to avoid other organs is
preferred, this approach is not always possible because of intervening
structures such as bowel loops, bones, major blood vessels, or lungs. Although
these structures can be transgressed when necessary, doing so increases the
risk of complications. Some techniques that have been used to avoid
penetrating interposed structures include changing the patient's position,
performing the biopsy during a different phase of respiration, tilting the
gantry, using geometric triangulation, instilling saline or carbon dioxide to
displace intervening structures, and using abdominal compression devices
[1,2,3].
A curved needle can also be used for this purpose. A review of the literature
revealed only a few reports describing the curved-needle technique
[4,
5].
A commercially available coaxial bone biopsy set with a straight outer
needle and a curved 13-gauge needle allows sampling from various locations in
the bone. At our institution, we use a CT-guided coaxial biopsy technique with
a straight 18-gauge outer guide needle and a custom-tailored curved 22-gauge
biopsy needle for circumventing intervening structures. This technique also
allows sampling of different parts of the lesion through the same guide
needle, potentially increasing the diagnostic yield. A curved needle may also
be used to compensate for the suboptimal trajectory of the guide needle. In
our report, we describe the CT-guided curved-needle coaxial technique with a
few illustrative cases and discuss the advantages and limitations of this
technique.
Subjects and Methods
Curved-needle biopsies are performed with a coaxial technique using CT
guidance. We use 22-gauge needles (Chiba; Cook, Bloomington, IN) for obtaining
aspiration biopsy specimens; the needle tip is grasped with hemostat forceps
without totally closing the jaws of the forceps and is gently bent to impart a
curve to the distal part of the needle shaft. Alternatively, the needle tip
may be curved against a 10-mL syringe. Before starting, it is important to
ensure that the biopsy needle is not sharply angled or kinked and that the
inside stylet slides freely in and out of the needle. Most commercially
available 22-gauge Chiba needles can be easily curved because of their
flexibility. The degree and length of curvature are based on the depth and
location of the target area in relation to the tip of the guide needle.
An 18-gauge guide needle (Chiba, Cook; or Hawkins needle, Medical Device
Technologies, Gainesville, FL) is placed in the proximity of the target lesion
using CT scans to monitor needle path and to verify the final position of the
needle tip. Occasionally, the guide needle must be pulled away from the
lesion, providing a distance between the tip of the guide needle and the
lesion. This method gives the curved needle enough space to regain its desired
curve or shape on exiting the guide needle. The bevel of the needle is kept on
the convexity of the curvature; this allows us to use the needle hub as an
indicator of the direction that the curve will take once the inner needle
exits the guide needle.
The curved needle is advanced through the 18-gauge guide needle, rotated in
the desired direction while still within the guide needle, and then slowly
advanced beyond the tip of the guide needle into the area to be sampled.
Although the curved needle is straightened out while it is within the guide
needle, it regains its curve on exiting the guide needle. Advancing a curved
needle through the guide needle is often met with some resistance, which
suddenly decreases as the 22-gauge needle exits the guide needle. Taking note
of this change often gives the operator a good indication as to how far he or
she needs to advance the 22-gauge needle. Also, care must be taken while
withdrawing the stylet. This should be done by firmly holding the 22-gauge
needle cannula in place to prevent it from being pulled back with the stylet.
Occasionally, respiratory excursions or organ motion rotate the biopsy needle
away from the desired direction once it exits the guide needle. The ratation
of the needle can be prevented by holding the hub while advancing the needle
into the lesion. To prevent the curved needle from slicing through tissues,
the operator should keep the rotation to a minimum while the needle is still
in the tissues. The biopsy needle should be pulled back into the guide needle
before rotating it in a different direction. A cytologist should be present at
each biopsy to assess the adequacy of the specimen.
Results
The coaxial technique with a curved inner needle allows safe access to
deep-seated lesions surrounded by vital structures. Figure
1A,1B
illustrates the use of this technique to biopsy a portocaval node surrounded
by liver, stomach, gallbladder, pancreas, and the inferior vena cava. In
another patient (Fig.
2A,2B),
we successfully used a curved needle to avoid intervening bowel loops, aorta,
inferior vena cava, and the superior mesenteric vessels while sampling an
interaortocaval lymph node. We have also used this technique to compensate for
imperfect trajectory of the guide needle (Fig.
3A,3B)
and to sample different portions of a mass lesion (Fig.
4A,4B).
View larger version (159K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —53-year-old man with colon cancer. Transverse
contrast-enhanced CT scan shows portacaval lymph node (asterisk)
shielded anteriorly by pancreas (large white arrowhead), stomach
(small white arrowheads), gallbladder (black arrowheads),
and liver (small white arrows), and posteriorly by inferior vena cava
(large white arrow). Lateral transhepatic approach would have
involved transgression of liver mass (black arrows) and hence was not
considered safe.
|
|
View larger version (161K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —53-year-old man with colon cancer. Transverse CT scan
obtained with patient in prone position shows curved 22-gauge needle
(small arrow) coaxially advanced through straight 18-gauge needle
(large arrow) and passing between liver and inferior vena cava
(large arrowhead) to sample lymph node (small
arrowheads).
|
|
View larger version (130K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2A. —56-year-old woman with follicular lymphoma. Transverse
contrast-enhanced CT scan shows aortocaval node (small solid arrow)
surrounded by inferior vena cava (open arrow), aorta (large
arrowhead), pancreas (large solid arrow), and superior
mesenteric vessels (small arrowheads).
|
|
View larger version (166K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2B. —56-year-old woman with follicular lymphoma. Transverse CT
scan obtained with patient in prone position shows curved 22-gauge needle
(white arrow) advanced coaxially through 18-gauge needle (black
arrow) and passing between inferior vena cava (small arrowhead)
and aorta (large arrowhead) into node.
|
|
View larger version (129K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3A. —65-year-old man with gastric carcinoma and left adrenal
nodule. Transverse CT scan obtained with patient in prone position shows left
adrenal mass (arrow) shielded posteriorly by lung. Using the
triangulation technique, we inserted 18-gauge guide needle at level caudal to
mass and directed cranially. Straight 22-gauge needle (arrowhead)
coaxially introduced through guide needle is seen to miss adrenal mass.
|
|
View larger version (130K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3B. —65-year-old man with gastric carcinoma and left adrenal
nodule. Transverse CT scan obtained with patient in prone position shows
curved 22-gauge needle (arrowhead) used to sample adrenal mass
(arrow).
|
|
View larger version (132K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4A. —51-year-old woman with pancreatic mass. Transverse CT scan
obtained with patient in prone position shows coaxial needles with straight
22-gauge needle (arrowhead) passing by side of biliary stent
(arrow) to sample pancreatic mass. Aspiration yielded fibrosis and
few inflammatory cells but no malignant cells.
|
|
View larger version (140K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4B. —51-year-old woman with pancreatic mass. Transverse CT scan
obtained with patient in prone position shows curved 22-gauge needle
(arrowhead) passing lateral to biliary stent (arrow) to
sample different region of same mass. Aspirate revealed mucinous
adenocarcinoma of pancreas.
|
|
Discussion
Although curved needles are routinely used for transjugular liver biopsies,
only a few reports have described the use of curved needles for direct
percutaneous needle biopsies. Carrasco et al.
[4] reported the use of curved
20- to 23-gauge needles for fluoroscopically guided biopsies when skeletal or
visceral structures prevented a direct path. However, that method is
technically demanding, involving careful selection of the skin entry site to
circumvent the intervening structure, initial introduction of the needle in a
direction away from the lesion, and a gradual change in the direction of
needle insertion after the curved portion has been introduced to direct the
needle tip toward the lesion. Because the needle curve should be kept
correctly oriented throughout the procedure, the technique can be performed
only under real-time fluoroscopic control, limiting its use to
fluoroscopically visible lesions. Also, because Carrasco et al. did not use a
coaxial needle technique, repeated biopsy attempts would require reinsertion
of the needle.
Warnock [5] reported a case
in which curved needles were used, both directly and through a coaxial needle,
for CT-guided biopsy of a retroperitoneal mass to avoid puncture of the colon.
As our cases illustrate, the curved-needle coaxial biopsy technique can
provide a safe access route for deeply situated, relatively inaccessible
abdominal or pelvic lesions without transgression of intervening structures
such as major vessels, bowel, and other organs, thereby reducing the risk of
complications.
A curved needle can also be used to compensate for inaccurate needle
positioning—that is, when the guide needle is found to be slightly
off-course and the projected needle path suggests that a straight needle
advanced through the guide needle is likely to miss the target lesion. The
curved needle is advanced with the hub positioned to direct the curve toward
the lesion on the needle's exit from the guide needle. This method allows
sampling of the lesion without repunctures or tandem needle insertions, thus
avoiding multiple punctures of the overlying normal tissues. The ability to
obtain multiple samples without repunctures is particularly helpful if
placement of the guide needle has been difficult and time-consuming because of
the deep lesion location, such as when performing cephalad-angled adrenal
biopsies using the triangulation method by the posterior approach or when
repeated needle insertions can increase the risk of the procedure, as in lung
biopsies or transpulmonary biopsies.
The coaxial technique allows multiple tumor biopsy samples to be obtained
through a single guide needle. However, one potential problem of the coaxial
method is that after the first needle pass, subsequent passes tend to follow
the same path and may yield little additional tissue
[6]. To overcome this problem,
Kopecky et al. [7] described
the use of a special side-exiting guide needle for coaxial biopsy. The smaller
needle is advanced through this guide needle and exits through the side hole;
the guide needle is then rotated in 45° increments to allow sampling of
different regions of the mass with each pass. In contrast, the technique we
describe achieves the same result without the need for any specialized needle;
it can be performed with the conventional end-hole coaxial guide needles,
which are inexpensive and readily available.
If the initial aspirate from a coaxial biopsy with a straight inner needle
yields necrotic tissue or an otherwise nondiagnostic sample, a curved needle
advanced through the guide needle can be used to sample different regions of
the tumor without having to reinsert the outer needle. Many tumors, such as
pancreatic tumors, are known to be associated with extensive fibrosis and
inflammation. Hence, the mass seen on imaging may be larger than the actual
tumor itself and may show uniform density making it impossible to
differentiate viable from nonviable tumor. Occasionally, areas of tumor
necrosis and bleeding may also be radiologically indistinguishable from the
remainder of the tumor. In these situations, the use of a curved needle to
obtain material from various locations in the mass may increase the chances of
finding the viable sections of the tumor.
We believe that the ability to sample different parts of the target lesion
with the curved-needle coaxial technique is also potentially useful for biopsy
of lymphomatous lesions. When complemented by flow cytometry and
immunophenotyping, fine-needle biopsy allows accurate diagnosis and
subclassification of lymphomas; however, this requires a good aspirate with a
high cell count, often necessitating multiple needle passes. The initial
needle pass often causes bleeding within the sampled lesion, resulting in a
drop-off in specimen quality and cellular yield in subsequent biopsies from
the same site; the drop-off in cellular yield can be avoided by using a curved
needle and directing the curve to sample different parts of the lymph node
with each pass.
The major limitation of the curved-needle coaxial technique is the
inability to perform a core biopsy. It is not possible to impart a curve to a
cutting type core biopsy needle without compromising the needle's cutting
action; the attempt to use a curved core biopsy needle may also result in
shearing the slotted stylet. Hence, this technique cannot be used in cases in
which histologic analysis is essential, requiring larger caliber cutting
needles. At our institution, we generally start all percutaneous biopsy
procedures with fine-needle aspiration biopsy, with immediate assessment of
the specimens by the cytologist. In our experience and in our patient
population (many of our patients have a history of known malignancies and are
referred for biopsy of lung, liver, or lymph nodal lesions to evaluate for
metastatic disease), fine-needle aspiration alone provides a definitive
diagnosis in most patients. Another reason for our overall success with fine
needles may be the cytologist's on-site evaluation of specimen adequacy.
In conclusion, the described technique of coaxial needle biopsy using a
curved inner needle is helpful in selected cases, providing safe access to
lesions that are difficult to approach. This technique may also allow the
operator to correct for an inaccurately positioned guide needle and facilitate
sampling of tissue from multiple areas within the tumor without repositioning
the guide needle.
References
-
de Kerviler E, Guermazi A, Gossot D, et al. Use of an abdominal
compression device for CT-guided biopsy of enlarged abdominal or pelvic lymph
nodes. J Vasc Interv Radiol
1998;9:353
-357[Medline]
-
Langen HJ, Jochims M, Gunther RW. Artificial displacement of
kidneys, spleen, and colon by injection of physiologic saline and
CO2 as an aid to percutaneous procedures: experimental results.
J Vasc Interv Radiol
1995;6:411
-416[Medline]
-
vanSonnenberg E, Wittenberg J, Ferrucci JT, Mueller PR, Simeone JF.
Triangulation method for percutaneous needle guidance: the angled approach to
upper abdominal masses. AJR
1981;137:757
-761[Abstract/Free Full Text]
-
Carrasco CH, Wallace S, Charnsgavej C. Aspiration biopsy: use of a
curved needle. Radiology
1985;155:254[Abstract/Free Full Text]
-
Warnock NG. Curved needle technique for the avoidance of interposed
structures in CT-guided percutaneous fine-needle biopsy. J Comput
Assist Tomogr 1996;20:826
-828[Medline]
-
Sheiman RG, Fey C, McNicholas M, Raptopulos V. Possible causes of
inconclusive results on CT-guided thoracic and abdominal core biopsies.
AJR
1998;170:1603
-1607[Abstract/Free Full Text]
-
Kopecky KK, Broderick LS, Davidson DD, Burney BT. Side-exiting
coaxial needle for aspiration biopsy. AJR
1996;167:661
-662[Free Full Text]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
|
|
 
S. Gupta, H. L. Nguyen, F. A. Morello Jr, K. Ahrar, M. J. Wallace, D. C. Madoff, R. Murthy, and M. E. Hicks
Various Approaches for CT-guided Percutaneous Biopsy of Deep Pelvic Lesions: Anatomic and Technical Considerations
RadioGraphics,
January 1, 2004;
24(1):
175 - 189.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Introduction
Subjects and Methods
