DOI:10.2214/AJR.08.1068
AJR 2009; 192:159-164
© American Roentgen Ray Society
Is Gadolinium Necessary for MRI Follow-Up Evaluation of Cystic Lesions in the Pancreas? Preliminary Results
Michael Macari1,
Terrence Lee1,
Sooah Kim1,
Stacy Jacobs1,
Alec J. Megibow1,
Cristina Hajdu1,2 and
James Babb1
1 Department of Radiology, Abdominal Imaging, New York University School of
Medicine, New York University Medical Center, Tisch Hospital, 560 First Ave.,
Ste. HW 201, New York, NY 10016.
2 Department of Pathology, New York University School of Medicine, New York
University Medical Center, Tisch Hospital, New York, NY.
Received April 14, 2008;
accepted after revision July 24, 2008.
Address correspondence to M. Macari
(Michael.Macari{at}nyumc.org).
Abstract
OBJECTIVE. The purpose of our study was to determine whether
gadolinium is necessary in the follow-up evaluation of pancreatic cystic
lesions.
MATERIALS AND METHODS. Fifty-six patients with pancreatic cystic
lesions detected on initial MRI and who underwent follow-up MRI were
identified. Mean cyst size was 1.9 cm, and mean follow-up was 9.1 months. MRI
included multiacquisition T1- and T2-weighted sequences before contrast
administration and 3D fat-suppressed T1-weighted images before and after
gadolinium administration. Two radiologists independently reviewed the entire
initial examination and follow-up MRI using only unenhanced T1- and
T2-weighted sequences from the second examination. Each radiologist made one
of three recommendations: 1, no follow-up necessary or follow-up imaging in
6-12 months; 2, cyst aspiration; or 3, cyst resection. Four weeks later,
imaging studies were reevaluated with the contrast-enhanced images from the
second examination. A second recommendation using the same outcomes was made.
Interobserver and intraobserver variations for the same patient were
summarized in terms of kappa coefficients and the percentage of times the
decisions were concordant. A 95% CI for the percentage of times management
decisions would change without and with gadolinium was calculated.
RESULTS. Concordance between the two different readers for the
interpretations (when using the same MRI interpretation technique for
follow-up surveillance) was 87.5% with a kappa coefficient to assess
interobserver variation of 0.075, suggesting only slight agreement between the
two readers. However, treatment recommendations provided by a single reader
with and without information from the contrast-enhanced images were discordant
only 4.5% of the time. Recommendations were concordant without and with
gadolinium 95.5% (107/112; 
= 0.67) of the time, suggesting substantial
agreement. A retrospective consensus review of the five cases in which
gadolinium effected a change in the observer's recommendation was performed.
There was nothing on the gadolinium-enhanced sequences that would specifically
alter a change in a management decision, and it is likely that the changes in
management decisions in these five cases were simply related to expected
variations in categorizing lesions rather than to the use of gadolinium.
CONCLUSION. The use of gadolinium has minimal impact in the
follow-up MR assessment of pancreatic cystic lesions.
Keywords: gadolinium • management • MRI • pancreatic cyst
Introduction
Pancreatic cystic lesions are being detected with increasing
frequency using imaging techniques. One study using T2-weighted MRI showed the
presence of pancreatic cystic lesions in 19% of 1,444 patients
[1]. The differential diagnosis
of these lesions includes benign (pseudocysts, serous cystadenomas) and
potentially malignant (side-branch intraductal papillary mucinous neoplasms,
peripheral mucinous cystic neoplasms) lesions. The age and sex of the patient
as well as the clinical history (prior pancreatitis) can be helpful in
suggesting the cause of a pancreatic cystic lesion. Moreover, a number of
imaging features, particularly on MRI, of the cyst may allow a confident
diagnosis to be made or at least suggested
[2-5].
Because the biologic behavior of these lesions is unknown and the imaging
diagnosis may be indeterminate, follow-up strategies are frequently used. The
clinical options available for incidentally detected pancreatic cystic lesions
are numerous. Dismissal of the lesion is a reasonable option, especially if
the cyst is small (< 1 cm); unilocular; or is detected in a patient who is
older, has serious comorbidities, or has a history of pancreatitis. For larger
cystic lesions, a number of potential strategies may be used
[6]. These include follow-up
surveillance imaging (typically with MRI or endoscopic sonography), cyst
aspiration (usually performed with endoscopic sonography), and resection
(especially if the imaging features suggest possible malignancy or if the
patient is symptomatic)
[6].
A number of studies have suggested that pancreatic cystic lesions < 3 cm
and incidentally detected show no significant morphologic change on follow-up
studies
[7-10].
However, the exact imaging techniques and follow-up intervals remain
controversial. An initial follow-up of 6 months followed up by annual imaging
and perhaps even prolonged surveillance may be appropriate if the lesion
remains stable in size [6]. MRI
has several advantages for follow-up of cystic lesions. Superior contrast
resolution improves detection of septations and debris; duct communication can
be established; size can be easily measured; and, most important, there is no
ionizing radiation.
On MRI, gadolinium-enhanced sequences are often added to an MR
cholangiopancreatography (MRCP) acquisition. If the contrast-enhanced
sequences could be eliminated without affecting decision making, a number of
potential advantages would be realized. First, the additional cost of the
gadolinium would be eliminated. Second, patient anxiety would be decreased
because of decreased time in the magnet and no requirement for an IV
injection. Third, concern about the risk of nephrogenic systemic fibrosis
would be eliminated because gadolinium would not be used.
We wanted to test the incremental value of unenhanced and
gadolinium-enhanced dynamic 3D T1-weighted sequences over that provided by the
unenhanced sequences encompassed within our protocol (in- and opposed-phase
T1-weighted sequences, axial and coronal single-shot fast spin-echo sequences,
and 3D MRCP) in detecting any change in the lesion that would result in a
change in management. Therefore, the purpose of this study was to determine
whether gadolinium-enhanced MRI is necessary in the follow-up imaging of
previously detected pancreatic cysts.
Materials and Methods
Patients
Institutional review board approval for this retrospective study was
obtained, and the study was performed in full compliance with HIPAA
regulations. From an MRI database, we retrospectively identified 56 patients
with a pancreatic cystic lesion detected on an initial MRI examination and who
in addition underwent follow-up MRI from 2005 through 2007. All patients were
initially being evaluated for suspected pancreaticobiliary abnormality
(abnormal liver function tests [n = 30], biliary calculi [n
= 15], pain [n = 11]) and underwent MRI using our routine abdominal
MRCP protocol. There were 17 men and 39 women with a mean age of 73 years (age
range, 34-88 years). Mean cyst size was 19 mm (range, 9-144 mm), and mean
follow-up was 9.1 months (range, 5-23 months) between the MRI
examinations.
MRI Technique
Both the initial and follow-up examinations were performed with the
identical protocol at 1.5 T using either an Avanto or Symphony scanner
(Siemens Medical Solutions) with a torso phasedarray coil. A 22-gauge IV
catheter was inserted into an arm vein before imaging.
In all patients, imaging was performed with a breath-hold spoiled
gradient-echo T1-weighted sequence using a dual-echo for in- and opposed-phase
imaging (TR/first-echo TE, second-echo TE, 180/4.7, 2.3); breath-hold T2
weighting using either a STIR sequence (TR/effective TE, 2,530/76) with
inversion time of 150 milliseconds or fat-suppressed turbo spin-echo technique
(3,900/101); and breath-hold axial and coronal half-Fourier acquisition
single-shot turbo spin-echo (HASTE) T2-weighted sequences (900/88, 150°
flip angle, 4- to 6-mm-thick sections, no gap). The final sequence was a
volumetrically acquired 3D fat-suppressed gradient-recalled echo sequence
(3.9/1.6) before and during the arterial phase and at approximately 60 and 200
seconds after IV administration of 15-20 mL of gadopentetate dimeglumine
(Magnevist, Bayer HealthCare) injected via an MR-compatible power injector
(Solaris MR-compatible Power Injector, Medrad). The arterial acquisition was
determined and acquired after a 1-mL test bolus was injected. Between the
venous and delayed phases of enhancement, a 3D MRCP acquisition with fat
suppression was obtained (2,500/684, 140° flip angle, 1-mm-thick
sections). All data were sent to a Leonardo PACS (Siemens Medical Solutions)
from which data were evaluated.
Data Evaluation
Two abdominal radiologists with 1 and 4 years of experience, respectively,
in pancreatic MRI evaluated the data. The radiologists were aware of the study
design but blinded to any clinical information other than age and sex of the
patients. First, the two reviewers independently analyzed data from the entire
initial MRI examination and data from the follow-up MRI examination using only
the unenhanced T1- and T2-weighted sequences. The data were analyzed for:
changes in cyst size, changes in cyst content, and presence or absence of
ductal communication. On the basis of this evaluation of the data, the
reviewers made one of three recommendations: 1, probably benign lesion and
either no follow-up necessary or continued follow-up in 6-12 months; 2,
indeterminate lesion, recommend cyst aspiration; and 3, probably malignant
lesion, cyst resection recommended. The reviewer's assessment of benign,
indeterminate, and probably malignant was based on the subjective imaging
findings of cyst morphology, change in size, internal septation, presence or
absence of perceived ductal communication, and mural nodularity. Small
unilocular cysts (< 2.0 cm) without septations or nodularity were
considered benign. Larger lesions or lesions that showed thin internal
septations or slight mural nodularity were considered indeterminate. Lesions
with thick irregular septations or those with mural nodularity were considered
probably malignant.
The cases were reevaluated 2-4 weeks later by the same readers in a
different order from the initial interpretation to decrease recall bias.
During the second review, the entire initial MRI examination and all the data
from the follow-up MRI examination (including unenhanced T1- and T2-weighted
sequences and gadolinium-enhanced data) were analyzed. Again, on the basis of
the evaluation of this data, the reviewers made one of three recommendations:
1, probably benign lesion and either no follow-up necessary or continued
follow-up in 6-12 months; 2, indeterminate lesion, cyst aspiration using
endoscopic sonography to assess cyst content; and 3, probably malignant
lesion, cyst resection recommended.
Statistical Analysis
Interobserver agreement—Each reader rendered two management
decisions for each of the 56 patients, once using the initial examination and
follow-up imaging without gadolinium and then using the initial examination
and the entire follow-up examination including the gadolinium-enhanced
sequences. Therefore, the data consisted of a total of four management
decisions for each of 56 patients. Concordance agreement between the
management decisions (recommendations) provided by the two readers for the
same patient was summarized in terms of kappa coefficients and the percentage
of times the decisions were concordant. To account for the dependency of the
different measurements on the same patient, kappa was first calculated per MRI
interpretation technique (with vs without the use of the gadolinium-enhanced
sequences), and the results were used to calculate an overall kappa
[11].
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Fig. 1A —35-year-old woman with biliary colic. Cyst in tail of pancreas was
incidentally detected during MRI. Axial single-shot fast spin-echo (SSFSE)
T2-weighted image shows 21-mm cyst (arrow) in tail of pancreas.
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Fig. 1C —35-year-old woman with biliary colic. Cyst in tail of pancreas was
incidentally detected during MRI. Axial 3D gradient-recalled echo (GRE)
T1-weighted image obtained at 60 seconds shows same thin septations within
cyst (arrow).
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Fig. 1D —35-year-old woman with biliary colic. Cyst in tail of pancreas was
incidentally detected during MRI. Follow-up axial SSFSE T2-weighted image 14
months after A-C shows same 21-mm cyst (arrow) in tail of
pancreas is stable in size.
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Fig. 1E —35-year-old woman with biliary colic. Cyst in tail of pancreas was
incidentally detected during MRI. Follow-up axial 3D GRE T1-weighted image
obtained at 60 seconds shows same cyst is unchanged (arrow).
Follow-up examination with gadolinium did not contribute to change in
management recommendations. One reader recommended continued follow-up imaging
in 1 year without and with use of gadolinium and second reader recommended
cyst aspiration without and with use of gadolinium. Patient ultimately
underwent cyst aspiration, revealing glycogen-rich fluid without mucin, and
diagnosis of serous cystadenoma was made.
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Intraobserver agreement—Agreement between the management
decisions (recommendations) made for the same patient by a single reader (one
decision made with and the other without information from the
contrast-enhanced follow-up images) was summarized using kappa coefficients
and the percentage of times the decisions were concordant. To account for the
dependency of the different measurements on the same patient, kappa was first
calculated per reader and the results used to calculate an overall kappa
[11].
Logistic regression for correlated data was used to derive a 95% CI for the
percentage of times use of gadolinium can be expected to change management
decisions. Specifically, generalized estimating equations (GEEs) based on a
binary logistic regression model were used to model the probability that
decisions made with and without the gadolinium-enhanced images would be
concordant. The dependent variable was the binary indicator of agreement
between the decisions made for a given patient. Because each patient
contributed two binary assessments to the analysis, one from each of the two
readers, the correlation structure was modeled by assuming observations to be
correlated only when derived for the same patient. Within the GEE framework,
Wald statistics were used as a basis for constructing a CI for the probability
that the use of gadolinium can be expected to change management decisions
(i.e., a CI for 1 minus the probability of concordance between the unenhanced
data and the addition of gadolinium-based decisions provided by a given reader
for a given patient). SAS, version 9.0, software (SAS Institute) was used for
all statistical computations.
Results
Interobserver Agreement
Concordance between the two different readers for the interpretations (when
using the same MRI interpretation technique for follow-up surveillance) was
87.5% (49/56) for follow-up using MRI with gadolinium and 87.5% (49/56) for
follow-up using MRI without gadolinium. That is, 98 of 112 total decisions
were the same between the two independent readers. In the 14 cases in which
there were differences between the readers, the differences were related to
one reader recommendation of 1 and the second reader recommending 2. The kappa
coefficient to assess interobserver agreement with respect to management
decisions was found to be 0.075, suggesting that there was only slight
agreement between the readers
[11].
Intraobserver Agreement (Without and With the Use of Gadolinium)
A management decision was provided by each of the two independent readers
using each of two MRI interpretation techniques (without and with the use
gadolinium) for all 56 subjects. The recommendations of reader 1 were
concordant in 94.6% (53/56; = 0.6) of cases without and with the use
of gadolinium and were concordant in 96.4% (54/56; = 0.74) of cases
for reader 2 (Table 1).
Overall, the management decisions derived on the basis of the two
interpretation techniques (without and with the use of gadolinium) were
concordant 95.5% (107/112; = 0.67) of the time suggesting substantial
agreement between the techniques.
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TABLE 1 : Percentage of Time Same or Different Decision Was Rendered Using
Gadolinium-Enhanced Sequences as Was Rendered Using Unenhanced
Sequences
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Fig. 2A —58-year-old woman with cyst in tail of pancreas incidentally
detected on MRI. Axial single-shot fast spin-echo (SSFSE) T2-weighted image
(A) and axial 3D gradient-recalled echo T1-weighted image (B)
obtained at 60 seconds show 11-mm simple-appearing cyst (arrows) in
tail of pancreas.
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Fig. 2B —58-year-old woman with cyst in tail of pancreas incidentally
detected on MRI. Axial single-shot fast spin-echo (SSFSE) T2-weighted image
(A) and axial 3D gradient-recalled echo T1-weighted image (B)
obtained at 60 seconds show 11-mm simple-appearing cyst (arrows) in
tail of pancreas.
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Fig. 2D —58-year-old woman with cyst in tail of pancreas incidentally
detected on MRI. Follow-up axial SSFSE T2-weighted image 13 months after
A-C shows same 11-mm cyst (arrow) in tail of pancreas is
stable in size. In this case, gadolinium-enhanced images did not contribute to
change in follow-up recommendations, both readers suggesting continued imaging
surveillance on basis of review of data without and with gadolinium-enhanced
sequences.
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Overall, a change in a management decision was observed only 4.5% of the
time when interpreting follow-up MRI data with gadolinium compared with
interpretation without the use of gadolinium (Figs.
1A,
1B,
1C,
1D,
1E,
2A,
2B,
2C, and
2D). The 95% CI for the
percentage of times the use of additional gadolinium-enhanced sequences will
lead to change in a management decision when following up a known pancreatic
cystic lesion is 1.5-10.0%.
Changes in Initial Assessment After the Use of Gadolinium
One hundred four initial interpretations were graded as 1, benign lesion
with either no follow-up necessary or continued follow-up in 6-12 months
suggested (Table 2). After the
use of gadolinium, two of these 104 (1.9%) decisions were changed to a grade
of 2, indeterminate cyst, aspiration using endoscopic sonography to assess
cyst content recommended. Two of six initial interpretations of 2,
indeterminate lesion, cyst aspiration using endoscopic sonography to assess
cyst content, were changed to a grade of 1. One of six initial decisions of 2
was changed to 3, cyst resection recommended. None of the initial decisions of
3 were changed after the use of gadolinium.
A consensus review of the five cases in which gadolinium caused a change in
the observer's recommendation of patient management was performed. In
retrospect, there was nothing on the gadolinium-enhanced sequences that would
specifically alter a change in a management decision (Figs.
3A,
3B, and
3C). Therefore, it is likely
that the changes in management decisions in these five cases were simply
related to expected variations in categorizing lesions as opposed to truly
being related to the use of gadolinium.
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Fig. 3A —85-year-old woman undergoing MRI for evaluation of abnormal liver
function tests. Coronal single-shot fast spin-echo (SSFSE) T2-weighted image
shows multiloculated 2.5-cm cyst in body of pancreas (arrow). On
other images, ductal communication appeared to be present, suggesting
intraductal papillary-mucinous neoplasm. Note iron in liver.
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Fig. 3B —85-year-old woman undergoing MRI for evaluation of abnormal liver
function tests. Axial SSFSE T2-weighted image obtained 7 months after A
shows same multiloculated 2.5-cm cyst in body of pancreas (arrow).
Cyst did not appear changed in size. Reader 1 suggested continued follow-up on
basis of unenhanced interpretation. Reader 2 also recommended cyst aspiration
on basis of unenhanced interpretation. This reflects interobserver
variation.
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Fig. 3C —85-year-old woman undergoing MRI for evaluation of abnormal liver
function tests. Axial 3D gradient-recalled echo T1-weighted image obtained
during same examination as B at 60 seconds shows same cyst
(arrow). Cyst did not appear changed in size. Reader 1 suggested
continued follow-up on basis of complete MRI examination including
gadolinium-enhanced images. Reader 2 recommended resection when interpreting
image set with gadolinium. This reflects both interobserver variation and
intraobserver variation. Because of patient comorbidities, the lesion was
neither resected nor aspirated.
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Discussion
Pancreatic cystic lesions are being detected with increasing frequency
using modern cross-sectional imaging techniques. This is especially true on
MRI [1]. There are many
different cystic lesions that occur in the pancreas. The most common
pancreatic cystic lesion is a pseudocyst
[12]. However, the
differential diagnosis is broad and includes infectious cysts and cystic
neoplasms [12,
13]. Most cystic neoplasms
identified in the pancreas are benign
[14,
15]. These include almost all
serous cystadenomas and most small intraductal papillary-mucinous neoplasms
(IPMNs) and peripheral mucinous cystadenomas. However, mucinous tumors (both
IPMNs and mucinous cystadenomas) have malignant potential or even can be
malignant at the time they are detected. Other rare cystic lesions of the
pancreas include cystic islet cell tumors, mucinous cystadenocarcinoma, and
cystic adenocarcinoma [13].
Imaging features that favor malignancy include increasing size > 3 cm,
mural nodularity, and extrapancreatic spread
[7,
14].
The decision on how to manage a patient when a cystic lesion is identified
in the pancreas is controversial, and no clear guidelines have been
established. However, for mucinous cystic lesions, a consensus panel suggests
that cysts may be followed up or resected on the basis of imaging appearance
and patient comorbidities [6].
Clinical decisions based on imaging findings should be made using the imaging
features of the cyst, the age of the patient, and whether the patient is
symptomatic. Most large cysts (> 3 cm) with or without mural nodules or
those that are symptomatic require intervention. On the other hand, when a
small (
1 cm) simple cyst is seen in the pancreas in an elderly
individual, the lesion can likely be ignored because the chance that this
lesion will ever cause harm to the patient is remote. However, when a small,
relatively simple-appearing cystic lesion measuring between 1 and 3 cm that is
not clearly a pseudocyst or serous cyst adenoma is detected in a younger or
middle-aged individual, further evaluation is required
[7-10].
Many of these pancreatic cystic lesions are followed up with imaging
surveillance. The exact imaging interval for follow-up of pancreatic cystic
lesions is not clear. A 6- to 12-month follow up is often suggested, and
further recommendations can be made at the time of the follow up examination
on the basis of stability or growth
[6].
For follow-up of a pancreatic cystic lesion with imaging, MRI offers clear
advantages compared with MDCT. First, no radiation is involved. This is
especially relevant if the cyst is detected in a younger individual who may
need to undergo multiple future surveillance imaging examinations
[16]. Second, because of the
excellent contrast resolution, especially of T2-weighted sequences, the
external morphology, internal cyst content (debris, nodularity, and
septations), and presence or absence of ductal communication are better
appreciated on MRI than on MDCT. Finally, because iodinated contrast material
is not administered, the risk of contrast-induced allergy and nephrotoxicity
are much lower than on MDCT, in which iodinated contrast is necessary.
However, there are some potential limitations of MRI compared with MDCT in
the imaging follow-up of pancreatic cystic lesions. Imaging examination times
on MRI are substantially longer than for MDCT. Some of the additional MRI time
is related to obtaining the contrast-enhanced data. The additional time is
related to inserting an IV catheter into an arm vein, connecting it to a power
injector, performing a timing-run acquisition for the contrast acquisition,
and the contrast-enhanced sequences themselves. If gadolinium were not
necessary, the examination time could be substantially shortened. Moreover, in
those patients with borderline renal function, the potential risk of
nephrogenic systemic fibrosis would be eliminated
[17].
In our study, we found substantial interobserver disagreement regarding the
management decisions rendered. The kappa coefficient to assess interobserver
variation in the treatment decisions was 0.075, suggesting only slight
agreement between the two readers
[11]. However, despite this
relatively high level of interreader variation (12.5% discordance between
readers with respect to decisions rendered using the same data set), treatment
decisions provided by a single reader with and without information from the
gadolinium-enhanced sequences were discordant only 4.5% of the time.
Therefore, although the readers exhibited marked differences in their
interpretations of the same data set, each reader was quite consistent in the
interpretation of the two data sets (with and without the use of gadolinium)
for a single patient. This suggests that the contrast-enhanced images provided
very little information that each individual reader considered pertinent to
decision making.
In only five cases was a management recommendation changed on the basis of
the additional gadolinium-enhanced data. This is because changes in clinical
decisions are primarily based on lesion growth. When an uncharacterized cystic
lesion is observed to grow, a decision to aspirate the cyst fluid to better
determine whether the lesion is a pseudocyst, serous, or mucinous lesion is
warranted. It is well known that some benign cystic lesions, such as serous
cystadenomas and pseudocysts, may grow. Serous cystadenomas have been shown to
grow, and the larger they are, the more likely they are to grow
[18]. If a benign cystic
lesion (pseudocyst or serous cystadenoma) is noted to grow on surveillance
imaging, a decision to intervene (resect) may be necessary if the patient is
symptomatic from the growing lesion. On the other hand, if a lesion is
observed to be stable in size or decrease on surveillance imaging, either
continued follow-up or no further imaging may be necessary, based on the age
of the patient and overall imaging appearance of the cyst.
The use of gadolinium may have some advantages for follow-up of pancreatic
cystic lesions. The use of subtraction imaging may show enhancing nodules or
thick irregular septations. However, mural nodularity and internal septations
are easily seen on T2-weighted sequences, and the presence of a change in
these features should be easily shown when comparing the surveillance
examination with the initial examination. Moreover, worrisome enhancing
features on the initial MRI examination should prompt earlier intervention
rather than surveillance. Finally, if a worrisome feature is identified on a
follow-up MRI examination performed without gadolinium to evaluate a
pancreatic cyst, the patient could always return for a gadolinium-enhanced
study if necessary. This scenario should be extremely rare.
There are some limitations to our study. We do not know the histology of
most of the cystic lesions in this study. Although some cystic lesions
included in this study had microcystic morphology (suggesting serous cyst
adenoma) and some cases showed ductal communication (suggesting IPMN), our aim
was not to evaluate lesion characterization but to determine if the addition
of gadolinium led to changes in imaging decision making. Moreover, most of the
time when evaluating a cystic pancreatic lesion detected on imaging in
clinical practice, the histology is not definitely known and decisions are
based on the age, symptomatology, and imaging findings.
Second, most of the cystic lesions in our study were relatively small (1-3
cm) and simple-appearing and were categorized as requiring no additional
imaging or continued surveillance. Cystic lesions initially detected on MRI
with more worrisome features are likely to be treated interventionally rather
than followed-up. Again, our findings show that in these rather
simple-appearing cystic lesions, gadolinium had minimal impact on decision
making.
In conclusion, our study showed that in the follow-up imaging surveillance
of previously detected pancreatic cystic lesions, gadolinium had minimal
impact in decision making. By avoiding the routine use of gadolinium in
patients being followed up for pancreatic cysts, the additional cost of the
gadolinium can be eliminated, patient anxiety can be decreased, and concerns
regarding nephrogenic systemic fibrosis would be eliminated.
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Abstract
Introduction
