ArticlePDF Available

CT-guided indirect percutaneous facet synovial cyst rupture combined with direct fenestration: 10-year review at a single institution

Authors:

Abstract and Figures

Background Facet synovial cysts (FSCs) are benign, extradural outpouchings arising from the facet joint that can cause radiculopathy. Effectiveness of CT-guided indirect percutaneous cyst rupture (IPCR) alone and direct fenestration (DF) treatment alone have previously been reported in large cohorts. We performed a retrospective review of all FSCs treated under CT-guidance at a single institution where patients underwent IPCR, and IPCR followed by DF if necessary. We hypothesized that CT-guided FSC rupture would demonstrate similar effectiveness to previously reported fluoroscopic-guided methods, with potential improvement due to the opportunity to employ the DF technique in cases of IPCR failure. Methods A search was conducted of all CT-guided FSC rupture procedures over 10 years. Data included demographics, needle gauge used for IPCR and DF, rupture success, cyst size and T2 intensity, presence of spinal hardware, and cyst location. Subsequent surgery at the level of the cyst was documented. Results 90 FSC rupture attempts were performed on 75 patients (28 M/47 F). FSC rupture using IPCR had a 70.0% success rate. In 22 FSC rupture attempts, IPCR failed and was followed by DF, with a success rate of combined IPCR + DF of 90.6 %. Subsequent surgery was required for 36.0% of patients involving the same level as the cyst or cysts. Conclusion Rates of successful FSC rupture under CT-guidance increased when the indirect rupture technique could be followed by direct fenestration in cases of failure. Our findings emphasize the benefits of flexibility afforded to the operator with CT-guidance.
Content may be subject to copyright.
CT-guided indirect percutaneous facet synovial cyst rupture combined with
direct fenestration: 10-year review at a single institution
Allison Y. Yang
a,*
, Troy A. Hutchins
b
, Lubdha M. Shah
b
, Lacey Woods
c
, Ghazaleh Safazadeh
b
,
Blair A. Winegar
b
, Anna Hudson
b
, Miriam E. Peckham
b
a
Department of Radiology and Imaging Sciences, Indiana University, United States
b
Departments of Radiology and Imaging Sciences University of Utah Health Sciences Center, United States
c
University of Utah School of Medicine, United States
ABSTRACT
Background: Facet synovial cysts (FSCs) are benign, extradural outpouchings arising from the facet joint that can cause radiculopathy. Effectiveness of CT-guided
indirect percutaneous cyst rupture (IPCR) alone and direct fenestration (DF) treatment alone have previously been reported in large cohorts. We performed a
retrospective review of all FSCs treated under CT-guidance at a single institution where patients underwent IPCR, and IPCR followed by DF if necessary. We hy-
pothesized that CT-guided FSC rupture would demonstrate similar effectiveness to previously reported uoroscopic-guided methods, with potential improvement due
to the opportunity to employ the DF technique in cases of IPCR failure.
Methods: A search was conducted of all CT-guided FSC rupture procedures over 10 years. Data included demographics, needle gauge used for IPCR and DF, rupture
success, cyst size and T2 intensity, presence of spinal hardware, and cyst location. Subsequent surgery at the level of the cyst was documented.
Results: 90 FSC rupture attempts were performed on 75 patients (28 M/47 F). FSC rupture using IPCR had a 70.0% success rate. In 22 FSC rupture attempts, IPCR
failed and was followed by DF, with a success rate of combined IPCR +DF of 90.6 %. Subsequent surgery was required for 36.0% of patients involving the same level
as the cyst or cysts.
Conclusion: Rates of successful FSC rupture under CT-guidance increased when the indirect rupture technique could be followed by direct fenestration in cases of
failure. Our ndings emphasize the benets of exibility afforded to the operator with CT-guidance.
1. Introduction
Facet synovial cysts (FSCs) are benign, extradural, uid-lled out-
pouchings that arise from synovium in the setting of chronic spinal facet
motion and degenerative facet arthropathy, most commonly at the L4/5
level [1,2]. When present, FSCs can impinge upon the intradural neural
elements, as well as exiting and transiting nerve roots, which may
manifest as intractable back pain, radiculopathies, neurogenic claudi-
cation, and, in rare cases, cauda equina syndrome [1].
Treatment options for patients with FSCs generally include non-
operative medical management, surgical excision, indirect percuta-
neous cyst rupture (IPCR) via the facet joint itself (Fig. 1), or direct
fenestration (DF) (Fig. 2) [2,3]. IPCR has been found to achieve statis-
tically and clinically signicant pain relief in patients [4]. Some imaging
markers, specically inherent T2 signal intensity of FSCs, have been
found to directly correlate with success of percutaneous rupture, i.e.
high and intermediate signal intensity cysts are signicantly easier to
rupture than low signal intensity cysts, although the reason for this is not
entirely clear [5].
Access of the facet joint under image guidance may be performed
using either uoroscopy or computed tomography (CT). Use of uo-
roscopy provides real-time assessment of needle trajectory in the ante-
roposterior and lateral planes and can also minimize the radiation dose
to the patient relative to CT [6]. Fluoroscopically-guided procedures use
the IPCR method to treat FSCs, accessing the facet joint from a posterior
approach, conrming intra-articular needle placement by contrast in-
jection, and using high pressure to indirectly rupture the cyst [4,7]. FSCs
treated with IPCR under uoroscopic guidance have been reported to be
successful in up to 81% of cases [8], with an overall success rate of
55.8% as shown in a meta-analysis of 29 studies [9]. A potential
downside of using uoroscopic technique, however, is that it only shows
a two-dimensional evaluation of contrast spread into the epidural space
to conrm rupture [10,11], which can be difcult to differentiate from
the retrodural space of Okada [12]. On the other hand, intervention with
* Corresponding author.
E-mail addresses: yangay@iu.edu (A.Y. Yang), Troy.Hutchins@hsc.utah.edu (T.A. Hutchins), Lubdha.Shah@hsc.utah.edu (L.M. Shah), Lacey.Woods@hci.utah.
edu (L. Woods), Ghazaleh.Safazadeh@hci.utah.edu (G. Safazadeh), Blair.Winegar@hsc.utah.edu (B.A. Winegar), Aewillis10@gmail.com (A. Hudson), Miriam.
Peckham@hsc.utah.edu (M.E. Peckham).
Contents lists available at ScienceDirect
Interventional Pain Medicine
journal homepage: www.journals.elsevier.com/interventional-pain-medicine
https://doi.org/10.1016/j.inpm.2024.100447
Received 30 September 2024; Received in revised form 29 October 2024; Accepted 3 November 2024
Interventional Pain Medicine 3 (2024) 100447
2772-5944/Published by Elsevier Inc. on behalf of International Pain & Spine Intervention Society. This is an open access article under the CC BY-NC-ND license
( http://creativecommons.org/licenses/by-nc-nd/4.0/ ).
CT, albeit a more limited procedural resource, can be instrumental for
accessing joints in patients who may have anatomical variations or large
osteophytes which complicate facet joint access [6]. Under CT-guidance,
FSCs can be treated using the less invasive IPCR method as in uoros-
copy, as well as the more invasive DF technique via an interlaminar
approach to directly aspirate and/or rupture the cyst [2]. The advan-
tages of CT include [1]: accurate visualization of contrast extravasation
into the epidural space to conrm successful cyst rupture (Fig. 1) [13],
and [2] the ability to use a DF technique in the case of IPCR failure
(Fig. 2).
The effectiveness of CT-guided IPCR FSC treatment alone and DF FSC
treatment alone have previously been reported in large cohorts. In our
study, we performed a retrospective review of all FSCs treated under CT-
guidance at a single institution where patients underwent IPCR, DF, or a
combination of techniques over the last ten years. We hypothesized that
CT-guided IPCR would be similarly effective when compared to previ-
ously reported uoroscopic-guided methods in the literature, with
potentially improved effectiveness due to the opportunity to employ the
DF technique in cases of IPCR failure. We investigated the patient de-
mographics, pre-procedure FSC imaging features, and procedure tech-
niques in order to determine if any of these were associated with
successful cyst rupture or the need for subsequent surgical intervention.
2. Materials and methods
This exploratory retrospective, single-arm cohort/case series was
conducted under an institutional review board-approved protocol, and
informed consent was waived.
2.1. Subjects
We conducted a search in the Nuance mPower (Montage, Burlington,
Massachusetts) database for all CT-guided facet synovial cyst rupture
procedures performed within the last ten years, August 2012 - August
2022. Search terms included ‘facet AND synovial AND cyst AND needle
AND rupture.Results were ltered by Exam description, including ‘CT
guidance needle placement and ‘CT guided cyst aspiration and ‘CT
guided needle biopsy. Data for each case, including accession number,
patient sex, patient age, and report text, were exported into Microsoft
Excel Spreadsheet (Microsoft Corporation, Redmond, Washington).
Next, a search was conducted in the Picture Archiving and
Communication System (PACS) using the accession numbers to record
corresponding medical record numbers, demographic information, level
of intervention, presence of spinal hardware, needle gauge used, suc-
cessful indirect rupture (which was determined by contrast
extravasating into the ventral or dorsal epidural fat pad or into the
foramina), and follow-up direct fenestration and rupture attempt, as
applicable. Additionally, pre- and post-procedure pain scores by
numeric rating system were recorded as available. For each patient, the
most recent pre-intervention lumbar MR images were accessed to record
cyst size in greatest biaxial dimension, cyst location, and cyst T2 in-
tensity. Chart review was performed on each patient to assess rates of
subsequent surgery at the same level of prior intervention during the
study period.
2.2. Procedural technique
All cases were performed by one of three operators with a range of
215 years of procedural experience during the 10-year search period
and used techniques established by the practice. Pre-procedure MR
imaging was reviewed for each patient to determine precise location of
each FSC. Potential risks of the procedure were discussed with the pa-
tient, including but not limited to bleeding, infection, or injury to sur-
rounding blood vessels, nerves, or the spinal cord. Each patient was
positioned prone on the table, and the overlying skin was prepped and
draped in the usual sterile fashion and anesthetized locally with 12%
lidocaine. Conscious sedation was achieved with IV Versed and Fentanyl
and titrated to effect under continuous physiologic monitoring.
All FSC ruptures were rst attempted using the less invasive IPCR
approach prior to consideration of using the more invasive DF approach.
Under CT-guidance, either a 17-, 18-, 20-, or 22-gauge needle (as
deemed by physician by patient anatomic factors) was placed with its tip
in the posterior aspect of the facet joint ipsilateral to the FSC. Contrast
was injected into the facet joint in order to visualize the lling of the
synovial cyst under CT. Once visualized, a mixture of 80 mg Depo-
Medrol, 1 cc of 0.5 % Bupivacaine, and 1 cc of normal saline was
forcefully injected into the facet joint to attempt indirect rupture of the
synovial cyst and bathe the epidural space at this level. Cyst rupture via
this indirect technique was conrmed by visualization of contrast
extravasating into the epidural space, after previously being contained
within the cyst. Upon procedure completion, the needle was removed,
and a sterile dressing applied to the area. If no contrast was seen
extravasating into the epidural space, additional indirect attempts were
performed using preservative-free normal saline to achieve FSC rupture.
If multiple (i.e. at least 3) subsequent IPCR attempts with normal
saline failed, the more invasive DF technique was performed as feasible
via an interlaminar approach. Under CT-guidance, a 17-, 18-, 20-, or 22-
gauge spinal needle was placed using either [1] an ipsilateral inter-
laminar approach or [2] a contralateral interlaminar approach in order
to access the FSC. Direct fenestration of the cyst was performed, and
Fig. 1. The indirect percutaneous cyst rupture technique as shown in three sequential procedural CT axial images. Image A demonstrates placement of a spinal
needle into the posterior aspect of the right facet joint, with injection of contrast to ll the joint space (arrow). Image B demonstrates contrast extending from the
joint and lling the FSC (arrow). Image C demonstrates extravasation of contrast into the right lateral and ventral aspects of the epidural space after successful FSC
rupture (arrows).
A.Y. Yang et al.
Interventional Pain Medicine 3 (2024) 100447
2
preservative-free normal saline was injected into the cyst to induce a
direct rupture. Subsequent CT images through the intervention site were
attained in order to conrm contrast extending from the cyst into the
epidural space, demonstrating a successful cyst rupture.
2.3. Statistical analysis
Analyses were performed to evaluate imaging and procedural vari-
ables and their effect on the following outcomes: success of IPCR, suc-
cess of IPCR followed by DF, and necessity for subsequent surgery at the
level of FSC. Successful IPCR or rupture via DF was dened by visuali-
zation of contrast extravasation through the epidural space. Statistical
analysis was performed using the Mann-Whitney test for non-parametric
variables, Student t-test for parametric continuous variables, and Fisher
Exact test for categorical variables. The variables analyzed were as fol-
lows: sex, age, hardware, needle gauge, cyst size in greatest bi-axial
dimension, and cyst T2 intensity, all of which were chosen to replicate
studies that have preceded ours, in order to determine the relationship
between each of these variables and successful cyst rupture at our
institution. The change in numeric rating scale between pre- and post-
procedure was correlated with procedure success, both in the IPCR
and IPCR +DF groups.
The T2 intensity of FSCs was evaluated by a neuroradiology
attending with 9 years of experience (BW) and neuroradiology fellow
with one year of experience (AH). They assigned categories of T2 signal
per the methods originally developed by Cambron et al. [5]. Weighted
Cohens Kappa Coefcient was used to report the reliability of the two
radiologists [14].
For analyses of predictor variables and their association with out-
comes, a total of 75 patients consisting of 90 FSC rupture attempts/90
cases were analyzed. Three procedures involved bilateral synovial cyst
ruptures. Patients sex and hardware status did not change between
procedures (n =75). Patients age, needle gauge, cyst size, and cyst
intensity changed between total cases (n =90). Three procedures used
the same MR ndings, and as such, T2 cyst intensity and size were
excluded from outcome calculations for these procedures (n =87). Data
Analyses were generated using STATA version 17 statistical software
[StataCorp. College Station, TX].
3. Results
3.1. Subjects
Ninety cases were yielded from our search. Three cases had no
intervention performed due to no cyst lling with contrast during the
procedure (one cyst previously seen on MRI not found to communicate
with the facet joint, one case found to represent facet hypertrophy on the
CT planning scan prior to intervention instead of a cyst, and one case
demonstrating a vascular structure rather than a cyst). However, we
included these cases as they would have likely undergone intervention
in the uoroscopic setting. The 90 FSC attempted ruptures remaining for
review were performed on 75 patients (28 males with an average 62.3
years of age; 47 females with an average 61.1 years of age) under CT-
guidance. Three cases involved bilateral FSCs (3.2%), with the
remainder being unilateral (96.8%). Eleven patients required repeated
FSC interventions [1]: 9 were treated twice [2], 1 was treated 3 times,
and [3] 1 treated 4 times in total. This resulted in a total of 90 FSCs being
treated in 90 cases involving 75 patients (Supplemental Table). There
were no procedural complications.
3.2. Inter-rater reliability
An inter-rater reliability analysis of cyst T2 signal intensity showed
Kw =0.65, which falls in the substantial level of agreement [15]. The
agreement values were dened as follows: 0 poor, 0.010.20 slight,
0.210.40 fair, 0.410.60 moderate, 0.610.80 substantial, and
0.811.00 almost perfect.
3.3. Overall rates of successful cyst rupture
63/90 (70.0%) FSCs were successfully treated using the IPCR
method alone. In 27 FSCs the IPCR method did not result in cyst rupture.
In 22 of these FSCs the failed rupture was subsequently followed by DF,
which was successful in 14/22 FSCs (63.6%). In 5 of these FSCs, DF was
not attempted due to anatomy barriers (no interlaminar window). The
overall success rate for FSC rupture using IPCR alone was 70.0% (63/90
FSCs), and the success rate of combined IPCR +DF was 90.6% in FSCs
where both techniques were attempted (77/85 FSCs, as 5 FSCs never had
a DF attempted).
Twenty-seven out of 75 patients required subsequent surgery
involving the same level as the cyst or cysts (36.0%). The average
amount of time after the attempted percutaneous cyst rupture to sub-
sequent surgery was 10.21 (standard deviation±15.23) months.
3.4. Association of age, sex, and presence of surgical hardware with
treatment outcomes
Neither age nor sex were found to be associated with success of IPCR
alone, IPCR +DF, or subsequent need for surgery (Table 1, Table 2).
Fourteen patients had surgical hardware, and of these, 13 (92.9%)
had the hardware present either directly adjacent to or at the same level
as the FSC. The presence of surgical hardware was also not found to be
Fig. 2. Failure of indirect percutaneous cyst rupture followed by successful rupture by direct fenestration. Image A demonstrates indirect lling of the FSC via lling
of the right facet joint (arrow). There was failure of rupture after multiple attempts at pressurizing the cyst indirectly. Image B demonstrates direct fenestration of the
cyst. This caused subsequent spillage of contrast into the epidural space (early extravasation noted by arrow).
A.Y. Yang et al.
Interventional Pain Medicine 3 (2024) 100447
3
associated with treatment success or subsequent need for surgery
(Table 1).
3.5. Association of procedural technique and treatment outcomes
An 18-gauge Quincke needle was most used in the IPCR technique
(82/90 FSCs, 91.1 %). Four FSC ruptures were attempted with a 20-
gauge Quincke needle, three with a 22-gauge Quincke needle, and one
used a 17-gauge needle. Needle gauge was not found to be associated
with treatment success of IPCR alone, IPCR +DF, or subsequent need for
surgery (Table 2).
3.6. Association of procedural outcomes and pain relief
Pre- and post-procedure pain scores were available in both the IPCR
+DF and IPCR alone groups. There were only 46 paired pain scores in
the IPCR +DF and 45 paired pain scores in IPCR alone group.
In IPCR +DF group, the mean change in pain scores was the same
between successful and unsuccessful procedures (3.8 vs. 3.3, p =
.83). In the IPCR alone group, those with unsuccessful rupture had a
slightly greater reduction in pain (4.3) compared to those with suc-
cessful rupture (3.5); however, it was not statistically signicant (p =
.45), (Table 3).
Given the similar levels of pain reduction across the success rates, it
suggests that procedural success of rupture did not immediately impact
the amount of pain relief, or that the sample sizes might be too small to
detect a signicant effect. There were not enough observations for
analysis in the group that subsequently underwent surgery.
3.7. Association of imaging features and treatment outcomes
Cyst size in greatest bi-axial dimension had a mean size of 46.4 mm.
Size was not found to be associated with treatment success of IPCR or
IPCR +DF. However, small cysts were more often found to require
subsequent surgery (mean of 44.2 mm vs 50.0 mm, p =.012) (Table 2).
Forty-two of the 87 FSCs with corresponding MRI demonstrated a bright
T2 signal, forty demonstrated an intermediate signal, and ve demon-
strated a dark signal on T2-weighted imaging. Intrinsic cyst intensity
was not found to be associated with success of IPCR, IPCR +DF, or
subsequent surgery.
4. Discussion
Our study is, to our knowledge, one of the rst to evaluate the
effectiveness of FSC rupture using a combination of IPCR, followed by
the DF technique in cases of IPCR failure, by employing CT-guidance.
We found a lower rate of rupture using IPCR under CT-guidance
Table 1
Patient-level characteristics and outcomes. (n =75).
Overall Success Success IPCR alone Subsequent surgery
No Yes p-value No Yes p-value No Yes p-value
Age mean (SD), y 61.52 (10.7)
Female 61.06 (10.7)
Male 62.28 (10.8)
Sex no. (%)
Female 47 (62.6) 10 (71.4) 37 (60.6) .45 19 (731) 28 (57.2) .17 32 (66.6) 15 (55.5) .34
Male 28 (37.3) 4 (28.5) 24 (39.3) 7 (27) 21 (42.8) 16 (33.3) 12 (44.4)
Hardware no. (%)
No 64 (85.3) 12 (85.7) 52 (85.2) .96 24 (92.3) 40 (81.6) .21 41 (85.4) 23 (85.2) .97
Yes 11 (14.7) 2 (14.3) 9 (14.8) 2 (7.7) 9 (18.4) 7 (14.6) 4 (14.8)
-Student t-test for parametric continuous variables and Fisher Exact or chi-squared test for categorical variables where appropriate.
Table 2
FSC rupture attempt characteristics and outcome.
Overall Success Success IPCR alone Subsequent surgery
No Yes p-
value
No Yes p-
value
No Yes p-
value
Age mean (SD), y (n =90) 66 (9.5) 61.7 (10.5) .15 62.7 (10.5) 62.1 (10.5) .78 62 (11.5) 63 (8.5) .67
Needle Gauge no. (%) (n =90)
Any 18 13 (100) 69 (89.6) .22 26 (96.3) 56 (88.9) .25 51 (89.572) 31 (94) .47
Other 0 8 (10.4) 1 (3.7) 7 (11.1) 6 (10.5) 2 (6)
Cyst size median [IQR], mm (n =
87)
a
46 [32.2,
52.5]
46.7 [35.7,
91.5]
.44 47.6 [32.8,
66]
45.8 [35.7,
80.2]
.92 50 [37.2,
100.7]
44.2 [30,
57.6]
.012
T2 Signal no. (%) (n =87)
a
Hyper-intense (H) 3 (23) 39 (52.7) .10 9 (33.3) 33 (55) .15 24 (43.5) 18 (56.3) .41
Intermediate (I) 9 (69.3) 31 (41.9) 16 (59.3) 24 (40) 28 (51) 12 (37.5)
Hypo-intense (L) 1 (7.7) 4 (5.4) 2 (7.4) 3 (5) 3 (5.5) 2 (6.1)
-Student t-test used for parametric continuous variables (Age),-Mann-Whitney test for non-parametric variable (Cyst Size), and Fisher Exact or chi-squared test for
categorical variableswhere appropriate.
-Cyst size: L x W (mm), calculated by multiplying the two greatest biaxial dimensions in millimeters.
a
In three FSC rupture attempts same MR was used and were excluded.
Table 3
Absolute pain score change from pre-to post-procedure.
obs mean change (SD) p-value
IPCR þDF Success (n =46)
Yes 43 3.8 (3.1) 0.83
No 3 3.3 (3.5)
IPCR Alone Success (n =45)
Yes 33 3.5 (3.3) 0.45
No 12 4.3 (2.7)
- Student t-test.
- Pain scores were documented on a scale of 010 (0: no pain, 10: the worst
pain).
A.Y. Yang et al.
Interventional Pain Medicine 3 (2024) 100447
4
compared to what has been previously reported using uoroscopy in a
large cohort (70.0% vs 81% [8]). However, we found a higher rate of
successful FSC rupture when IPCR was followed by DF (90.6%), and
combining the IPCR and DF techniques resulted in a higher rate of
success than uoroscopically guided IPCR alone rates, which has been
described in prior meta-analyses (55.8%) [9].
Rates of success with IPCR combined with DF in our study were
overall similar to a previously reported IPCR alone CT-guided study,
which reported an 87% success rate [5]. Though our study utilized
slightly different techniques (e.g. needles used in the Cambron et al.
study included a 14-gauge to penetrate covering facet osteophytes), our
high rate of success emphasizes the value of CT-guided intervention to
not only allow for repeated attempts until unequivocal rupture with the
less invasive initial IPCR approach, but also the exibility to transition
to the more invasive DF technique, which we have shown increases the
likelihood of FSC rupture.
Prior studies have examined radiologic FSC features, and association
with subsequent surgical conversion in one study of 45 patients found no
correlation between cyst signal intensity, size, facet effusion, spondy-
lolisthesis, canal stenosis, or facet edema with eventual surgery [7]. In
comparison, our study, with a larger cohort, interestingly found an as-
sociation between smaller cyst size and the need for subsequent surgery.
This result was somewhat surprising, and we surmise that smaller cysts
may perhaps have an easier time reforming than larger cysts, which in
turn, results in persistent symptoms for the patient. However, it is not
certain from these ndings that the symptoms requiring FSC treatment
and subsequent surgery were caused by these small cysts, and our as-
sumptions based on this correlation are therefore limited. Cambron et al.
found in their study of 110 patients that cysts with higher intrinsic T2
intensity were more likely to rupture using the IPCR technique, and they
hypothesized that the higher proportion of uid within the cyst im-
proves ease of IPCR compared to lower intensity cysts, which may be
more characteristically gelatinous or calcied. They also discussed that
increased T2 intensity led to fewer subsequent surgeries compared to the
cohort with more hypointense cysts. Our study, however, did not nd
these same associations, potentially limited by our lower sampling
power with a smaller patient cohort.
Rates of surgical intervention following IPCR +DF were found to be
lower in our CT-guided cohort than previously reported in a large IPCR
by uoroscopy study in 101 patients (36.0% vs 54% [8]), and more
similar to other uoroscopically-guided studies demonstrating a con-
version rate of 2038.7% [7,9,16].
Strengths of our study include the ability to unequivocally conrm
FSC rupture with CT-guidance. Single and bi-planar views with uo-
roscopy may not be as denitive, as we suspect there may be a
component of false positive ruptures when assessing rupture under
uoroscopic guidance versus CT. This may partially account for the
discrepancy between CT conrmed success, and previously reported
uoroscopic success.
One limitation of our study includes the retrospective nature of our
investigation with absence of patient-reported outcomes, and inconsis-
tent collection of pre and post pain scores, which limited our analyses.
There is also a lack of repeat MR imaging in some patients that went
underwent repeat rupture, as clinicians might order a repeat interven-
tion upon return of symptomatology with the assumption of recurrence
instead of obtaining post-procedural MR imaging, which partially limits
our determination of associated imaging variables. Additionally, we
could only track subsequent surgery in this patient cohort if it occurred
at our institution which may under-represent this percentage.
5. Conclusion
Conrmed FSC rupture via indirect technique under CT-guidance
was lower compared to previously reported uoroscopic-guided
studies in the literature, but the rates of successful rupture increased
with the addition of the direct fenestration technique. Our ndings
emphasize the benets of exibility afforded to the operator with a CT-
guided approach. CT guided direct fenestration may be indicated to treat
FSCs that fail uoroscopic or CT-controlled indirect rupture.
Declaration of competing interest
The authors declare that they have no known competing nancial
interests or personal relationships that could have appeared to inuence
the work reported in this paper.
Appendix A. Supplementary data
Supplementary data to this article can be found online at https://doi.
org/10.1016/j.inpm.2024.100447.
References
[1] Ramhmdani S, Ishida W, Perdomo-Pantoja A, Witham TF, Lo SL, Bydon A. Synovial
cyst as a marker for lumbar instability: a systematic review and meta-analysis.
World Neurosurg 2019;122:e105968. Epub 2018/11/12. doi: 10.1016/j.
wneu.2018.10.228. PubMed PMID: 30415048.
[2] Shah VN, von Fischer ND, Chin CT, Yuh EL, Amans MR, Dillon WP, et al. Long-term
effectiveness of direct CT-guided aspiration and fenestration of symptomatic
lumbar facet synovial cysts. AJNR Am J Neuroradiol 2018;39(1):1938. Epub
2017/11/11. doi: 10.3174/ajnr.A5428. PubMed PMID: 29122762; PubMed
Central PMCID: PMC7410714.
[3] Boody BS, Savage JW. Evaluation and treatment of lumbar facet cysts. J Am Acad
Orthop Surg 2016;24(12):82942. Epub 2016/10/30. doi: 10.5435/jaaos-d-14-
00461. PubMed PMID: 27792054.
[4] Lutz GE, Nicoletti MR, Cyril GE, Harrison JR, Lutz C, Solomon JL, et al.
Percutaneous rupture of zygapophyseal joint synovial cysts: a prospective
assessment of nonsurgical management. Pm r 2018;10(3):24553. Epub 2017/08/
12. doi: 10.1016/j.pmrj.2017.07.078. PubMed PMID: 28797833.
[5] Cambron SC, McIntyre JJ, Guerin SJ, Li Z, Pastel DA. Lumbar facet joint synovial
cysts: does T2 signal intensity predict outcomes after percutaneous rupture? AJNR
Am J Neuroradiol 2013;34(8):16614. Epub 2013/03/02. doi: 10.3174/ajnr.
A3441. PubMed PMID: 23449657; PubMed Central PMCID: PMC3801423.
[6] Bykowski JL, Wong WH. Role of facet joints in spine pain and image-guided
treatment: a review. AJNR Am J Neuroradiol 2012;33(8):141926. Epub 2011/09/
24. doi: 10.3174/ajnr.A2696. PubMed PMID: 21940805.
[7] Bell J, Bhatia M, Hadeed MM, George J, Hill A, Novicoff WM, et al.
Fluoroscopically guided facet cyst rupture: rate of conversion to surgery and risk
factor analysis. Clin Spine Surg 2021;34(7):E410. e4. Epub 2021/02/27. doi:
10.1097/bsd.0000000000001146. PubMed PMID: 33633003.
[8] Martha JF, Swaim B, Wang DA, Kim DH, Hill J, Bode R, et al. Outcome of
percutaneous rupture of lumbar synovial cysts: a case series of 101 patients. Spine J
2009;9(11):899904. Epub 2009/08/12. doi: 10.1016/j.spinee.2009.06.010.
PubMed PMID: 19664971.
[9] Shuang F, Hou SX, Zhu JL, Ren DF, Cao Z, Tang JG. Percutaneous resolution of
lumbar facet joint cysts as an alternative treatment to surgery: a meta-analysis.
PLoS One 2014;9(11):e111695. Epub 2014/11/13. doi: 10.1371/journal.
pone.0111695. PubMed PMID: 25389771; PubMed Central PMCID: PMC4229115.
[10] Wagner AL. CT uoroscopy-guided epidural injections: technique and results.
AJNR Am J Neuroradiol 2004;25(10):18213. Epub 2004/12/01. PubMed PMID:
15569755; PubMed Central PMCID: PMC8148733.
[11] Lee B, Lee SE, Kim YH, Park JH, Lee KH, Kang E, et al. Evaluation of contrast ow
patterns with cervical interlaminar epidural injection: comparison of midline and
paramedian approaches. Medicina (Kaunas) 2020;57(1). Epub 2020/12/31. doi:
10.3390/medicina57010008. PubMed PMID: 33374193; PubMed Central PMCID:
PMC7823639.
[12] Murthy NS, Maus TP, Aprill C. The retrodural space of Okada. AJR Am J
Roentgenol 2011;196(6):W7849. Epub 2011/05/25. doi: 10.2214/ajr.10.5751.
PubMed PMID: 21606270.
[13] Ortiz AO, Tekchandani L. Improved outcomes with direct percutaneous CT guided
lumbar synovial cyst treatment: advanced approaches and techniques.
J Neurointerventional Surg 2014;6(10):7904. Epub 2013/11/28. doi: 10.1136/
neurintsurg-2013-010891. PubMed PMID: 24280130.
[14] Cohen J. Weighted kappa: nominal scale agreement with provision for scaled
disagreement or partial credit. Psychol Bull 1968;70(4):21320. Epub 1968/10/
01. doi: 10.1037/h0026256. PubMed PMID: 19673146.
[15] Landis JR, Koch GG. The measurement of observer agreement for categorical data.
Biometrics 1977;33(1):15974. Epub 1977/03/01. PubMed PMID: 843571.
[16] Eshraghi Y, Desai V, Cajigal Cajigal C, Tabbaa K. Outcome of percutaneous lumbar
synovial cyst rupture in patients with lumbar radiculopathy. Pain Physician 2016;
19(7):E101925. Epub 2016/09/28. PubMed PMID: 27676672.
A.Y. Yang et al.
Interventional Pain Medicine 3 (2024) 100447
5
ResearchGate has not been able to resolve any citations for this publication.
Article
Full-text available
Background and objectives: The purpose of this study was to compare and to analyze contrast spread patterns between the paramedian and midline approaches to cervical interlaminar epidural injection (CIEI). Materials and Methods: We retrospectively enrolled 84 CIEI cases that had been performed for unilateral cervical spinal pain from April 2019 to April 2020. After 3 mL of contrast had been injected into the epidural space, fluoroscopic images were obtained. The CIEI was divided into a midline (Group M, n = 42) and a paramedian (Group P, n = 42) approach by anteroposterior imaging. The P Group was classified into a more medial (Group Pm, n = 26) and a more lateral (Group Pl, n = 16) group. Using ImageJ on an anteroposterior image, we assessed the grayscale brightness ratio of the ipsilateral or contralateral side of the vertebral body as well as the intervertebral disc space one level just above the needle location. We identified the dispersion of contrast into the ventral epidural space. Results: The grayscale brightness ratio was significantly higher in Group P than in Group M (p < 0.001). The incidence of ventral epidural spread in Group M was 57.1% versus 88.1% in Group P, which was significantly different (p = 0.001). Conclusions: The fluoroscopic CIEI finding in the paramedian approach predominantly showed an excellent delivery of the injectate to the ipsilateral side in comparison to the contralateral side. This showed a greater advantage in delivery toward ventral epidural space as compared to the midline approach.
Article
Full-text available
Purpose A comprehensive review of the literature in order to analyze data about the success rate of percutaneous resolution of the lumbar facet joint cysts as a conservative management strategy. Methods A systematic search for relevant articles published during 1980 to May 2014 was performed in several electronic databases by using the specific MeSH terms and keywords. Most relevant data was captured and pooled for the meta-analysis to achieve overall effect size of treatment along with 95% confidence intervals. Results 29 studies were included in the meta-analysis. Follow-up duration as mean ± sd (range) was 16±10.2 (5 days to 5.7 years). Overall the satisfactory results (after short- or long-term follow-up) were achieved in 55.8 [49.5, 62.08] % (pooled mean and 95% CI) of the 544 patients subjected to percutaneous lumbar facet joint cyst resolution procedures. 38.67 [33.3, 43.95] % of this population underwent surgery subsequently to achieve durable relief. There existed no linear relationship between the increasing average duration of follow-up period of individual studies and percent satisfaction from the percutaneous resolutions procedure. Conclusion Results shows that the percutaneous cyst resolution procedures have potential to be an alternative to surgical interventions but identification of suitable subjects requires further research.
Article
Study design: Retrospective case series at a single academic medical center. Objective: The aim was to determine if specific clinical, radiologic, and procedural factors are associated with conversion to surgery after fluoroscopically guided cyst rupture. Summary of background data: Percutaneous fluoroscopic rupture of facet cysts can often be the definitive treatment; however, it is unknown before the procedure who will ultimately proceed to formal surgical decompression. Differences in clinical, radiographic, and procedural factors of facet cysts may relate to the difference in efficacy of fluoroscopically guided cyst rupture. Methods: A continuous cohort of 45 patients who underwent fluoroscopically guided cyst rupture was evaluated. The primary outcome measured rate of conversion to surgery and of those that underwent surgery, the rate of decompression and fusion compared with fusion alone was noted. Secondary outcomes included analysis of clinical, radiologic, and procedural variables to determine if there were risk factors associated with conversion to surgery. Results: Twenty-nine percent of patients eventually underwent a surgical procedure with an average interval to surgery of 95 days after attempted rupture. Thirty-eight percent of patients that underwent surgery had a decompression and fusion. Failure of percutaneous cyst rupture trended toward significance for a future surgical decompression (P=0.08). Conclusions: Percutaneous facet cyst rupture is potentially a definitive treatment for this condition; however, it is unknown ahead of time who will proceed to definitive surgical decompression. On the basis of the data in this study, less than one-third of patients who had a fluoroscopically guided facet cyst rupture went on to surgery. There were no clinical, radiographic, or procedural details which could be used to robustly predict failure of percutaneous treatment. At this time, it is recommended to continue to attempt this nonoperative treatment intervention when there is a clinical indication after discussion of the risks and benefits with the patient.
Article
Background The pathogenesis of synovial cysts is largely unknown; however, they have been increasingly thought of as markers of spinal facet instability and typically associated with degenerative spondylosis. We specifically investigated the incidence of concomitant synovial cysts with underlying degenerative spondylolisthesis. Methods A literature search was performed using 4 online databases to assess the association between lumbar synovial cysts and degenerative spinal pathological features. Meta-analyses were performed on the prevalence rates of coexisting degenerative spinal pathological entities and treatment modalities. A random effects model was used to calculate the mean and 95% confidence intervals. Results A total of 17 studies encompassing 824 cases met the inclusion criteria. The pooled prevalence rates of concurrent spondylolisthesis, facet arthropathy, and degenerative disc disease at the same level of the synovial cysts were 42.5% (range, 39.0%–46.1%), 89.3% (range, 79.0%–94.8%), and 48.8% (range, 43.8%–53.9%), respectively. Among these, patients with coexisting spondylolisthesis were more likely to undergo spinal fusion surgery (vs. laminectomy alone) and reoperation than were patients without spondylolisthesis with a pooled odds ratio of 11.5 (95% confidence interval, 4.5–29.1; P < 0.0001) and 2.0 (95% confidence interval, 0.9–4.2; P = 0.088), respectively. Conclusions Patients with a combination of synovial cysts and degenerative spondylolisthesis are more likely to undergo spinal fusion surgery than laminectomy alone compared with patients with synovial cysts and no preoperative spondylolisthesis. Furthermore, patients with synovial cysts and spondylolisthesis are more likely to require additional fusion surgery. The results from the present review lend credence to the argument that synovial cyst herniation might be a manifestation of an unstable spinal level.
Article
Background and purpose: Lumbar facet synovial cysts are commonly seen in facet degenerative arthropathy and may be symptomatic when narrowing the spinal canal or compressing nerve roots. The purpose of this study was to analyze the safety, effectiveness, and long-term outcomes of direct CT-guided lumbar facet synovial cyst aspiration and fenestration for symptom relief and for obviating an operation. Materials and methods: We retrospectively reviewed the medical records and imaging studies of 64 consecutive patients between 2006 and 2016 who underwent 85 CT-guided lumbar facet synovial cyst fenestration procedures in our department. We recorded patient demographics, lumbar facet synovial cyst imaging characteristics, presenting symptoms, change in symptoms after the procedure, and whether they underwent a subsequent operation. We also assessed long-term outcomes from the medical records and via follow-up telephone surveys with patients. Results: Direct CT-guided lumbar facet synovial cyst puncture was technically successful in 98% of procedures. At first postprocedural follow-up, 86% of patients had a complete or partial symptomatic response. During a mean follow-up of 49 months, 56% of patients had partial or complete long-term relief without the need for an operation; 44% of patients underwent an operation. Patients with calcified, thick-rimmed, or low T2 signal intensity cysts were less likely to respond to the procedure and more likely to need an operation. Conclusions: CT-guided direct lumbar facet synovial cyst aspiration and fenestration procedures are safe, effective, and minimally invasive for symptomatic treatment of lumbar synovial facet cysts. This procedure obviates an operation in a substantial number of patients, even at long-term follow-up, and should be considered before surgical intervention.
Article
Background: Although lumbar zygapophyseal joint synovial cysts are fairly well recognized, they are an uncommon cause of lumbosacral radicular pain. Non-operative treatments include percutaneous aspiration of the cysts under computed tomography or fluoroscopic guidance with a subsequent corticosteroid injection. However, there are mixed results in terms of long-term outcomes and cyst reoccurrence. This study prospectively evaluates percutaneous ruptures of zygapophyseal joint (Z-joint) synovial cysts for the treatment of lumbosacral radicular pain. Objectives: Primary: To determine if percutaneous rupture of symptomatic Z-joint synovial cysts leads to sustained improvements in radicular pain and function. Secondary: To assess the rates of cyst recurrence and progression to surgical intervention following percutaneous rupture of symptomatic Z-joint synovial cysts. Design: Prospective cohort study. Setting: Outpatient academic spine practice. Participants: Adults with primary radicular pain due to a facet synovial cyst. Methods: Participants underwent fluoroscopically guided percutaneous Z-joint synovial cyst ruptures under standard-of-care practice. Data on pain, physical function, satisfaction, and progression to surgery were collected at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year post-rupture. An intention-to-treat analysis was utilized for assessment of patient-reported outcome measures. Main outcome measures: The Numerical Rating Scale, Oswestry Disability Index (ODI), and modified North American Spine Society questionnaires were used to measure pain, function, and satisfaction with the procedure, respectively. Results: Thirty-five participants were included in the study, and data were analyzed by an independent researcher. Statistically significant changes in ODI were reported at 2 weeks, 3 months, and 1 year post-intervention (p=.034, .040, and .039, respectively). A statistically and clinically significant relief of current pain was reported at 2 weeks (p=.025) and 6 weeks (p=.014) with respect to baseline. Patients showed significant improvements for best pain at 6 weeks with respect to baseline (p=.031). Patients' worst pain showed the greatest amount of improvement with clinically meaningful changes at all time points compared to baseline. Patient-reported satisfaction was found nearly 70% of the time at all time points. Forty percent (14/35) of participants required repeat cyst rupture, and 31% (11/35) required surgical interventions. Conclusions: There were statistically and clinically significant improvements in pain and function following percutaneous rupture of Z-joint synovial cysts. Additionally, the outcomes support previous retrospective studies indicating that approximately 40% of patients will need surgery. This study provides further research to determine the utility of this procedure and to precisely define a subset of ideal candidates.
Article
Lumbar facet cysts are a rare but increasingly common cause of symptomatic nerve root compression and can lead to radiculopathy, neurogenic claudication, and cauda equina syndrome. The cysts arise from the zygapophyseal joints of the lumbar spine and commonly demonstrate synovial herniation with mucinous degeneration of the facet joint capsule. Lumbar facet cysts are most common at the L4-L5 level and often are associated with spondylosis and degenerative spondylolisthesis. Advanced imaging studies have increased diagnosis of the cysts; however, optimal treatment of the cysts remains controversial. First-line treatment is nonsurgical management consisting of oral NSAIDs, physical therapy, bracing, epidural steroid injections, and/or cyst aspiration. Given the high rate of recurrence and the relatively low satisfaction with nonsurgical management, surgical options, including hemilaminectomy or laminotomy to excise the cyst and decompress the neural elements, are typically performed. Recent studies suggest that segmental fusion of the involved levels may decrease the risks of cyst recurrence and radiculopathy.
Article
Background: Lumbar synovial cysts can result from spondylosis of facet joints. These cysts can encroach on adjacent nerve roots, causing symptoms of radiculopathy. Currently the only definitive treatment for these symptoms is surgery, which may involve laminectomy or laminotomy, with or without spinal fusion. Surgery has been reported to successfully relieve radicular pain in 83.5% of patients by Zhenbo et al. Little information is available concerning the efficacy and outcome of percutaneous fluoroscopic synovial cyst rupture for treatment of facet joint synovial cysts. Objective: The goal of this investigation was to assess the efficacy of fluoroscopically guided lumbar synovial cyst rupture, in particular for its relief of radicular symptoms and its potential to reduce the need for surgical intervention. Study design: Retrospective evaluation of a case series. Setting: University hospital and urban public health care system. Methods: With approval from the Institutional Review Board of Case Western Reserve University/ MetroHealth Medical Center, we reviewed the medical charts of patients with lumbar radiculopathy who underwent percutaneous lumbar synovial cyst rupture. The 30 patients in the cohort were treated by one pain specialist between 2006 and 2013. These patients were diagnosed with moderate to severe lower back pain, radiculopathy, and ranged in age from 42 to 80 years. Patients were followed up for a minimum of 6 months and up to 24 months. Pre- and post-procedure pain assessments were reviewed by clinical chart review. In addition post-procedure pain assessments and duration of pain relief were obtained with telephone interviews. Pain had been reported by the patients using a numeric rating scale of 0 - 10 (0 = no pain; 10 = worst possible pain). Charts were reviewed to determine if surgery was eventually performed to correct radicular symptoms. Results: More than 6 months of pain relief was achieved in 14/30 patients (46%) and between one and 6 months of pain relief was achieved in 7/30 patients (23.3%). Nine patients (30.0%) had recurrence of the synovial cyst requiring repeat rupture and 6 patients (20.0%) required surgical intervention for cyst removal. A Wilcoxon signed-rank test demonstrated that the difference in numeric pain rating scale scores before and after the procedure was statistically significant (P < 0.0001). The average pain reduction was 71.2%. No complications were reported. Limitations: The results are limited by the retrospective nature of the data collection and the lack of detailed information regarding patients' functional improvement. Conclusions: Rupture of percutaneous lumbar synovial cysts in patients with lumbar radiculopathy was associated with immediate relief of radicular symptoms. In 80% of the patients, synovial cyst rupture eliminated the need for surgical interventions over the measured term. This minimally invasive procedure helps relieve pain in a subset of a patient population associated with these characteristics and is useful for management of this condition. Cyst expansion and failure to rupture with possible neuronal compression are the potential complications of this procedure. This complication did not occur in the study population. Key words: Fluoroscopically guided lumbar synovial cyst rupture, lumbar synovial cyst, lumbar zygapophyseal joint cyst, nonsurgical intervention, radiculopathy, spondylosis.
Article
To determine if lumbar synovial cyst rupture in symptomatic patients results in improved clinical outcome when using direct tandem and/or coaxial percutaneous CT guided techniques. 20 patients with unilateral lower extremity radiculopathy and/or low back pain underwent CT guided percutaneous treatment for their symptomatic lumbar synovial cysts. Cysts were identified with the use of a low osmolar non-ionic contrast agent via facet joint injection or through direct injection. Cyst rupture, using a direct tandem and/or coaxial technique, was attempted in all patients using an 18 gauge guide needle and a 22 gauge insert needle. Following attempted cyst aspiration, cyst rupture was performed using 1-3 mL of a mixture of methylprednisolone (2 mL, 80 mg) and bupivacaine (3 mL, 0.5%). All patients were followed-up in clinic for a minimum of 6 months after their procedures and up to a maximum of 24 months. 11 patients were male and nine were female, with an average age of 65.6 years. 17 patients presented with severe unilateral lower extremity radiculopathy and three patients were experiencing low back pain. One of the patients had two synovial cysts, and therefore a total of 21 lumbar synovial cysts were treated in this group of patients. Direct cyst puncture was achieved using a tandem technique in nine patients, a coaxial interlaminar approach in seven patients, a coaxial transforaminal approach in two patients, and a coaxial trans-facet approach in three patients. Cyst rupture was documented in all cases, as evidenced by CT confirmation of cyst decompression and contrast agent extravasation into the epidural space. The mean surveillance period in these patients was 18 months. Six patients experienced their usual radicular pain within 2 months of their treatment. Four of these patients were re-treated for recurrent smaller cysts. These patients have not had a recurrence at 24 months of follow up. Two of these six patients elected to undergo open surgical decompression without symptomatic improvement. No treatment related complications were observed in this group of patients. Direct tandem and/or coaxial percutaneous CT guided techniques for rupture and treatment of symptomatic lumbar synovial cysts reduces recurrence rates and therefore helps avoid more invasive open surgical procedures in this group of patients.