Keywords
textiloma - surgical sponges - pseudomass - postoperative
Background and Importance
Intracranial textilomas are retained surgical sponges, kept by the surgeon for filling
the postoperative space and achieving hemostasis, presenting as pseudomass lesions
in postoperative patients usually with surrounding inflammatory reaction. Though textiloma
is often used interchangeably with gossypiboma, some case reports use the later term
when there is foreign body reaction surrounding the retained sponges.[1]
[2]
[3] Intracranial textilomas are very rare with only few case reports available in literature.[4] Through this article we intend to describe the spectrum of imaging findings in intracranial
textilomas through clinicoradiological discussion of four postoperative cases. We
took our institutional ethical committee clearance for this study.
Clinical Presentation
Case 1
A 45-year-old female patient presented with complaints of headache and occasional
vomiting. Magnetic resonance imaging (MRI) showed well-defined extra-axial enhancing
mass lesion in right parafalcine region possibly representing large meningioma ([Fig. 1A]). Patient underwent craniotomy with excision of the lesion. Bipolar cautery was
used to achieve hemostasis and a single gelatin sponge was kept in the operative cavity.
Patient had uneventful postoperative course. Follow-up imaging was done after 3 months
of surgery. She was completely asymptomatic on follow-up. Follow-up computed tomography
(CT) scan showed ill-defined hyperdense lesion in right frontal region at the site
of surgery with few interspersed air foci and surrounding edema. MRIs revealed new
lesion that was relatively well-defined T2/fluid-attenuated inversion recovery (FLAIR)
isohyperintense with peripheral hypointensity in right frontal convexity with surrounding
mild vasogenic edema. The lesion showed peripheral post-contrast enhancement ([Fig. 1B]). The size of the lesion correlated with the size of the gelatin sponge kept as
a homeostatic device in the operative cavity. Also noted was residual right parafalcine
homogenously enhancing lesion. Since the patient was asymptomatic, no further management
was advised and patient was called up for routine follow-up imaging after 6 months.
Fig. 1 (a) Pre-operative MRI Images. Axial T2-weighted image (A), axial (B) and Coronal (C)
post-contrast T1-weighted images shows large well defined extra-axial hyperintense
lesion in right para-falcine frontal region causing marked mass effect over brain
parenchyma and surrounding vasogenic edema. The lesion shows intense enhancement with
non-enhancing component on inferomedial aspect of lesion. (b) Pre- operative MRI Images. Axial NCCT image (A) at the level just above the ventricles
shows post-operative changes as craniotomy and subdural hypodense collection in right
frontal region. There is relatively well defined hyperdense lesion with interspersed
air foci at the operative site. Axial T2W (B) and Axial FLAIR (C) images shows similar
post-operative changes in right frontal region. The lesion appears well defined with
central hyperintense signal intensity and peripheral hypointense capsule. Axial DWI
(D) shows intense restriction in central part of the lesion which was hypointense
on ADC images. Axial post contrast (E and F) T1-images shows thick smooth peripheral
enhancement in the lesion (blue arrow). Also noted is thick anterior falcine and frontal
convexity pachymeningeal enhancement with residual homogenously enhancing lesion in
right parafalcine region (red arrow).
Case 2
A 42-year-old female patient presented with chief complaints of chronic headache and
a single episode of seizures. MRI revealed an ill-defined infiltrating mass lesion
in right frontal region. Patient underwent craniotomy with partial excision of the
mass lesion. Hemostasis in the postoperative cavity was achieved using Surgicel (oxidized
cellulose) and fibrin sealant. Histopathology revealed anaplastic astrocytoma. Follow-up
MRI after 3 months revealed postoperative substance defect in right frontal region
with a relatively well-defined intra-axial T2/FLAIR hyperintensity and T1 hypointensity
at the operative site. The lesion showed internal T2 hypointense striations, mild
susceptibility changes, and peripheral diffusion restriction. There was smooth peripheral
contrast enhancement. CT images showed hyperdense lesion with interspersed air foci
([Fig. 2]). The size of the lesion was smaller than the size of the Surgicel kept in the operative
cavity.
Fig. 2 Post-operative MRI images. Axial T2W (A) and axial FLAIR (B) images show post-operative
gliotic changes in right frontal region. There is a well-defined centrally T2 hyperintense
lesion with peripheral hypointense rim and internal hypointense T2 striations at the
operative site in right frontal region. It is hypointense on FLAIR image (blue arrows).
Axial SWI (C) image shows peripheral susceptibility changes within the lesion. Axial
ADC image (D) shows mild diffusion restriction in the peripheral part of the lesion.
Axial pre- (E) and post-contrast (F) images shows smooth peripheral enhancement of
the lesion.
Case 3
A 3-year-old female child was operated for superior cerebellar pilocytic astrocytoma.
No operative details were available. She was asymptomatic after 1 year of surgery.
Follow-up MRI after 3 months revealed relatively well-defined intra-axial T2/FLAIR
peripherally hypointense and T1 mildly hyperintense lesion at the operative site.
The lesion showed peripheral susceptibility changes and mild diffusion restriction.
There was thick smooth peripheral post-contrast enhancement ([Fig. 3]). No perfusion was noted within the lesion and MR spectroscopy showed decreased
N-acetylaspartate (NAA) level. Since the lesion was present at the operative site
with MRI signal characteristics typical of homeostatic devices and different from
the original lesion, possibility of the textiloma was kept. Patient remained asymptomatic
with no increase in the size of the lesion/hemostatic device on follow-up MRI after
6 months.
Fig. 3 Post-operative MRI Images. Axial T2W (A) and axial FLAIR (B) images shows well defined
hypointense lesion with peripheral hypointense capsule in superior cerebellar vermis
at the operative site (yellow arrow). Axial SWI image (C) shows peripheral susceptibility
changes within the lesion. Axial ADC image (D) shows diffusion restriction in central
part of the lesion (arrow). Axial pre- (E) and post-contrast (F) T1-images shows thick
smooth peripheral enhancement of the lesion. Also noted is thick enhancement of left
sided tentorium.
Case 4
A 46-year-old female patient presented with chief complaints of headache, vomiting,
and seizures. MRI showed intra-axial infiltrating T2/FLAIR hyperintense mass lesion
with patchy areas of enhancement involving bilateral superior frontal lobes. Frontal
craniotomy and excision of mass were done. As in previous case, postoperative cavity
was filled with Surgicel (oxidized cellulose) and fibrin sealant to achieve hemostasis.
Histopathology revealed infiltrating astrocytoma. Patient presented with mild headache.
Follow-up MRI after 3 months revealed new lesion that was relatively well-defined
intra-axial T2/FLAIR isohyperintense lesion with peripheral hypointensity in right
frontal lobe with surrounding mild vasogenic edema. The lesion that appeared T1 hyperintense
showed central diffusion-weighted imaging (DWI) restriction, peripheral susceptibility
changes, and thick peripheral post-contrast enhancement. The lesion showed no perfusion.
MR spectroscopy showed decreased NAA levels with elevated Cho/Cr ratios ([Fig. 4]). After consultation with the neurosurgeon, it was apparent that the size of the
lesion matched the size of the Surgicel kept in the operative cavity. Based on the
appearances, possibility of textiloma was kept and follow-up MRI after 6 months was
advised.
Fig. 4 Post- operative MRI Images. Axial T2WI (A) shows well defined peripherally hypointense
lesion at the operative site in right frontal region. Axial ADC image (B) shows diffusion
restriction in central part of the lesion. Axial SWI image (C) shows peripheral susceptibility
changes within the lesion. Axial post-contrast T1-image (D) shows well defined hyperintense
lesion with thick smooth peripheral enhancement. Single voxel MR Spectroscopy (E,
TE-135) shows raised Cho/Cr and decreased NAA/Cr ratios. F) Axial perfusion image
(F, relative cerebral blood volume map) shows reduced perfusion in the lesion.
Discussion
Assessment of postoperative follow-up MRI scans in patients operated for intracranial
mass lesions requires thorough knowledge of the hemostatic agents used to prevent
repetitive hemorrhages. Different agents used such as simple cotton gauze, cellulose,
gelatin sponges, oxidized cellulose (Surgicel), Gelfoam wafers, or collagen tissue
have different MRI appearances that can be easily confused with residual or recurrent
mass lesion especially to inexperienced eye. Most of the cases of textilomas reported
in literature were mostly seen after abdominopelvic surgery with only limited literature
available for intracranial textilomas.[5] Surgicel is a hemostatic agent (blood-clot-inducing material) made of an oxidized
cellulose polymer (the unit is polyanhydroglucuronic acid).
Although mostly used as hemostatic agents to prevent recurrent bleeds at the operative
site, these agents are notorious for eliciting acute foreign body inflammatory changes
around them. These acute changes gradually turn into subacute to chronic type noncaseating
granulomatous inflammatory reaction.[6]
[7] This results in a demarcated inflammatory pseudomass that is easily confused with
post-chemoradiotherapy changes on postoperative MRI scans. The lesions in fibrotic
stages are asymptomatic and are detected incidentally on follow-up scans, while lesions
in exudative phase might become symptomatic in early postoperative period or later
depending on their location and size.[8] Here, we describe radiological appearances of these hemostatic agents to help our
radiology colleagues differentiate them from other lesions. Since these were left
purposely for hemostasis, no further management was needed in any case. No follow-up
scan was done in any case.
MRI appearances might vary depending on the type of material left, timing of MRI scan,
and the location of the hemostatic agent.[4] On conventional sequences, most of these agents appear as well demarcated focal
lesions mostly hypointense on T1-weighted (T1W) sequence. Signal changes on T2W images
could be hyperintense–hypointense depending on the fluid and protein contents. According
to literature, there is usually a peripheral T1 and T2 hypointense fibrotic capsule
that shows enhancement on post-contrast images.[7]
[9] Sometimes, internal linear T2W hypointense signal can be seen in hyperintense lesion
representing fibers of gauze material.[10] Some case reports are available where the patients were operated again and histopathology
showed granulomatous inflammatory reaction.[7]
[11] Differentiating textilomas from recurrent/residual lesions or post-radiochemotherapy
changes requires comparison of the imaging characteristics with preoperative imaging
and use of advanced MRI modalities like MR perfusion imaging and MR spectroscopy.
Though MRI is very helpful in diagnosing textilomas, histopathology correlation may
be needed in equivocal or questionable cases.[12] CT scan may also add up to the diagnosis of textilomas.[13]
Similar findings were noted in all our cases. The lesions, in our cases, were, however,
more hyperintense on T1-weighted imaging and showed DWI restriction representing proteinaceous
internal contents. Also, there was surrounding vasogenic edema with mild mass effect.
Thick peripheral T2 hypointensity representing fibrotic capsule was seen in our cases.
Dynamic susceptibility contrast perfusion done in our cases revealed perfusion defects
without raised cerebral blood volume and cerebral blood flow parameters. MR spectroscopy
findings were not specific. MR spectroscopy done in three cases showed decreased NAA
levels with increased Cho/Cr ratios. After consultation with the operating neurosurgeon,
it was apparent that the size of the lesions approximately matched the size of the
hemostatic agents kept in the operative cavity. CT scan done in two of our patients
revealed well-defined hyperdense masses with interspersed air foci as has been described
in literature.[13]
[14]
The final diagnosis of the intracranial textiloma should be made after consultation
with the operating neurosurgeon, comparison with the preoperative imaging, looking
at postoperative CT scans, use of advanced MRI sequences like perfusion, diffusion,
and MR spectroscopy and histopathology in questionable cases to reach the final diagnosis
especially if it has a medico-legal relevance.
Conclusion
Postoperative brain imaging is challenging. Intracranial hemostatic sponges are commonly
used nowadays and seen on the scan as “textilomas”; these can mimic residual/recurrent
lesions, postoperative abscesses, or radionecrosis. Careful clinical history and discussion
with surgeon before the evaluation of preoperative imaging and use of different modalities
can help reach the diagnosis and avoid pitfalls. Correct and timely diagnosis is important
for further treatment planning and patient care.
