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Skull Base Osseous Arteriovenous Fistula—A Rare Clinical Entity: Case Report and Literature Review
Accepted Manuscript Skull Base Osseous Arterio-venous fistula – a rare clinical entity : Case report and Literature Review Aneesh Mohimen, MD, Santhosh Kumar, E.R. Jayadevan PII:
S1878-8750(16)30961-5
DOI:
10.1016/j.wneu.2016.09.104
Reference:
WNEU 4644
To appear in:
World Neurosurgery
Received Date: 28 February 2016 Revised Date:
24 September 2016
Accepted Date: 26 September 2016
Please cite this article as: Mohimen A, Kumar S, Jayadevan ER, Skull Base Osseous Arterio-venous fistula – a rare clinical entity : Case report and Literature Review, World Neurosurgery (2016), doi: 10.1016/j.wneu.2016.09.104. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Title: Skull Base Osseous Arterio-venous fistula – a rare clinical entity : Case report and Literature
RI PT
Review.
ABSTRACT
SC
Purpose
To describe a rare clinical entity of intra-osseous skull base arterio-venous fistula managed with
M AN U
transvenous fistula embolization. Case details
57 year old lady presented with complaints of headache and episodic tinnitus with progressive left sided visual deterioration. Cross sectional imaging of the head revealed multiple vascular
TE D
channels in the sphenoid bone and in bilateral masticator spaces. Catheter angiography showed presence of a large osseous arterio-venous fistula (AVF) epicentered in the body of sphenoid and left pterygoid plates with arterial feeders from bilateral external carotid arteries and venous
EP
drainage. She was managed by transvenous coil and liquid embolic agent (Squid) embolization
AC C
of the venous sac with significant reduction of shunt. In the post procedure period the patient developed paradoxical worsening of symptoms due to central retinal Vein occlusion (CRVO). Conclusion
Skull base osseous fistulae are uncommon clinical entities and fistulae centered within the sphenoid bone are very rare. The aim of this report was to highlight management issues associated with such a case and review the available literature on the subject.
ACCEPTED MANUSCRIPT
INTRODUCTION: Skull base arterio-venous fistulae (AVF) with the site of fistula located within the bone are an
RI PT
uncommon set of clinical entities, described in literature only in small case series. The entity, initially described by Malik et al in 1994, is characterised by the presence of nidus within the bone, unlike the classical dural fistula where the nidus is located within the dura or sinus wall(1).
SC
The clinical presentation is variable and depends on the location of fistula and pattern of venous drainage. Various treatment approaches such as transarterial or transvenous embolization and
M AN U
surgical techniques have been described in the literature (2-5). Due to rarity of reports, a standardized approach to these lesions have not been determined. We encountered a patient with an osseous AVF within the sphenoid bone presenting with clinical features similar to indirect carotidocavernous fistula. The fistula was managed successfully with trans-venous coiling and embolization with liquid embolic agent (LED) Squid (Embofru ,Switzerland). In the
TE D
postoperative period, she developed worsening of ocular symptoms which warranted active ophthalmological intervention.
EP
In this report, we highlight the imaging features and therapeutic options of this uncommon entity along with a brief review of the available literature.
AC C
CASE REPORT:
A 50 year old lady presented with complaints of slowly progressing holocranial headache and episodic tinnitus of 6 months duration along with mild progressive visual deterioration in the left eye of 2 months duration. Clinical examination showed left sided visual acuity of 6/36 with left sided temporal hemianopia. Left temporal bruit was appreciated. MRI and CT scan of the head showed multiple vascular channels within the sphenoid bone and in bilateral masticator spaces
ACCEPTED MANUSCRIPT
suggestive of a skull base arterio-venous fistula (AVF). She underwent a digital subtraction angiogram (DSA) which confirmed the presence of a large osseous AVF epicentered in the body of the sphenoid and the left pterygoid plates. Arterial supply was from terminal branches of the
RI PT
internal maxillary artery (IMA), middle meningeal arteries (MMA) and deep temporal arteries (figure1). Venous shunting was noted into a large venous sac located within the pterygoid plates. Subsequent venous egress was noted into multiple veins into the cavernous sinuses bilaterally
SC
and into the pterygoid venous plexus. There was no evidence of cortical venous reflux or drainage via ophthalmic veins. Since, the nidus was extensive and the feeding arteries to the
M AN U
nidus were not clearly defined, she was planned for transvenous embolization. A 3DRA was obtained to delineate the access to the venous sac (figure2), which clearly demonstrated the communicating of the sac with the cavernous sinus. The venous sac was accessed from the left IJV through the left cavernous sinus using two micro catheters (Echelon 10,Covidien /
TE D
Medtronics) over a Traxcess wire (Microvention, Tustin, California,U.S.) and the sac was progressively occluded with coils and liquid embolic agent (LED) Squid 18 with near complete obliteration of the sac and near total fistula obliteration (figure 3). Two microcatheters were used
EP
to ensure that embolization could be continued in case of inadvertent prolapse of one of the catheters from the venous sac. The entry of venous sac into the cavernous sinus and was marked
AC C
in the monitor to avoid any inadvertent migration of embolic material into the sinus. In the immediate postoperative period she had significant resolution of tinnitus and headache. However on the second postoperative day, she complained of left sided visual deterioration. Ophthalmology evaluation revealed visual acuity of 6/60 with corneal edema, conjunctival congestion and cotton wool spots in the retina suggestive of central retinal vein occlusion (CRVO). She was managed conservatively with topical anti-glaucoma medications and a follow
ACCEPTED MANUSCRIPT
up ophthalmological evaluation after 2 weeks revealed intra-ocular pressure (IOP) of 34 mmHg on the left eye with neovascularisation of the left iris secondary to CRVO. She subsequently underwent two sittings of panretinal laser photocoagulation. On clinical follow up after 3
RI PT
months, her initial symptoms had subsided with visual acuity being static at 6/60. IOP was controlled at 20 mm Hg and retinal examination revealed regression of neovascularisation. The tinnitus and headache resolved completely and her visual status remained static on serial clinical
SC
follow up. Patient declined consent for follow up check angiography
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DISCUSSION:
Skull base osseous AVF are rare clinical entities with a handful of case series described hitherto in literature. There is considerable discrepancy with regard to the nomenclature of these entities and the protocols for planning appropriate treatment. Pure intra-osseous spontaneous AV shunts
TE D
were first described in 2 cases by Malik et al in 1994(1). The subsequent reports / case series and the management strategies have been detailed as per table 1. The 10 previously reported cases (1-5) have shown no specific gender predilection. The mean age of presentation was in the
EP
5th -6th decades with 2 cases reported presenting in the 2nd decade. Tinnitus (with headache) was the commonest clinical presentation with two patients presenting with hearing loss and one
AC C
patient with orbital congestive symptoms. While some authors (1,5) have named these entities as arterio-venous malformations (AVM), others have used the term AVF (2-4). There was no definied nidus evident in angiograms or 3D angiographic analysis and hence we assume that these lesions are mostly AVF. In addition, although they are anatomically distinct and confined to osseous space, embryologically, the shunts sharing a common involvement of the cranial dura, extra-dural space and the adjacent
ACCEPTED MANUSCRIPT
calvarial bone have been categorized as dural arteriovenous fistula (DAVF) (6). The etiology of purely osseous fistula is conjectural and may be similar to the development of DAVF. Inflammatory reaction secondary to venous thrombosis is posited as one of the inciting factor
RI PT
leading to DAVF formation. Thrombosis of dural sinus or emissary veins are speculated in the development of DAVF (7). Similarly, thrombosis of diploic vein induced by paranasal sinus inflammation or skull base infective process could possibly trigger inflammatory processes
Author / Year Age Sex(M/F)
1.
Malik et al / 1. 48y / M 1994 (1) 2. 49y / F
/ Clinical Features
Tinnitus with headache (both cases)
No of Nomenclature Cases
Site
2
Foramen Magnum 1. Surgery. 2. Trans-arterial -2
M AN U
Sl No
SC
which would ultimately lead to the formation of osseous fistula.
AVM
Management
embolization followed surgery.
by
Kim et al (2) 15y/M
Tinnitus, 1 headache, Hearing loss
AVF
Petrous and jugular Transvenous embolization foramen
Coil
3.
Jung et al Mean age : (3) 58.6 years; (range, 15– 82y)
Tinnitus 6 (commonest) Hearing loss – 1 case Diplopia – 1 case
AVF
Transvenous Clivus -2 embolization Petrous apex-1 Hypoglossal canal -4
coil
Tinnitus with headache
1
AVF
Parietal Bone
Trans-arterial LED (Onyx) embolization
1
AVM
Sphenoid
Trans-arterial LED (Onyx) embolization
AVF
Sphenoid
Transvenous coil & LED (SQUID) embolization
EP
TE D
2.
M:F- 4:2 Shim et al / 46y/F 2011 (4)
5.
Park et al / 43y/F 2013 (5)
Headache, orbital chemosis, proptosis
6.
Present Case
Tinnitus with 1 visual loss
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4.
50y/F
ACCEPTED MANUSCRIPT
Table 1 : Summary of reports of Skull Base Osseous AVF in Literature.
Surgical as well as endovascular techniques have been described to treat these pure osseous
RI PT
fistulas. The exact localization of the fistula becomes important while planning surgical options as significant haemorrhage can be expected during the procedure and obliteration of this fistula requires complete exposure of the affected bone (1). Endovascular approaches include
SC
transarterial and transvenous obliteration of the nidus or venous sac using coils or liquid embolization agents. Following the initial report by Malik et al, subsequent management of these
M AN U
fistulas were performed by endovascular transarterial or transvenous techniques (2-5). To achieve complete cure by endovascular approach, it is essential to obliterate the nidus and or the draining vein at the shunt site completely (8). The access route is chosen considering several parameters such as easy accessibility, risk of cranial nerve injuries and presence of dangerous
TE D
intracranial-extracranial anastomoses. In our case, there was extensive involvement of the sphenoid bone with feeders from meningeal branches of external and internal carotid arteries ,hence transarterial embolisation of the fistula was not considered appropriate as the risk of
EP
cranial nerve injuries and percolation of liquid embolization agent via collaterals into the intracranial circulation was high. Transvenous approach could not be clearly delineated on
AC C
conventional angiography due to high shunt flow and overlap of multitude primary draining vein with the nidus and hence, 3DRA was performed to study the draining pattern of the fistula. 3DRA clearly demonstrated site of fistula and the draining venous sac communicating with the cavernous sinus through a venous channel This vein was subsequently used for accessing the fistula. It also helped to delineate the safe limit of permissable reflux, to avoid inadvertent occlusion of cavernous sinuses, which drain normal brain parenchyma. Initial coils were
ACCEPTED MANUSCRIPT
deployed to reduce the amount of liquid embolic agent and we used two microcatheters to preserve the access in the event of microcatheter kickback.
RI PT
Interestingly, the patient developed CRVO in the postoperative period, although significant reflux into the superior ophthalmic vein (SOV) was not noted in the initial angiograms. Paradoxical worsening of symptoms following the treatment of indirect carotico-cavernous
SC
fistulae (CCF) has been described and it has been postulated to be due to the development of thrombosis within the SOV with thrombus extension into the central retinal vein, resulting in
M AN U
CRVO (9-11). If the anastomotic communication with choroidal veins is compromised, it may result in severe retinal ischemia and hemorrhagic retinopathy (11). In our case, even though the shunt flow was very high, it was promptly decompressed by cavernous sinuses and pterygoid plexus.In such situation, the SOV flow, even if not directly visualized, would be expected to be in antegrade direction, towards the cavernous sinus due to the venturi effect caused by high flow
TE D
situation. Stagnant flow within the SOV following shunt obliteration would have precipitated thrombosis and retrograde propagation into central retina vein would have resulted CRVO in our patient. It is important to identify this complication early, so that appropriate therapeutic
EP
measures such as control of intraocular pressure and possibly, anticoagulation can be considered
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to reduce or limit the extent of ocular injury. Literature review of previously reported cases treated with embolization showed complete improvement of tinnitus and headache (similar to our case). The two patients who had presented with hearing loss had no improvement after treatment (2,3). Complete immediate / delayed angiographic shunt obliteration was noted in 10 of the previous 11 cases. These results confirm that endovascular options are mainstay of treatment for managing unusual osseous fistulas and additional imaging with 3D angiograms can be a useful tool for the interventionist to decide on appropriate treatment strategy.
ACCEPTED MANUSCRIPT
CONCLUSION Skull base osseous dural fistulae are uncommon clinical entities and fistulae centered within the
RI PT
sphenoid bone are very rare. 3D rotational angiography is helpful to ascertain the location of fistula, to delineate the route of approach and to map out the safe limit of embolisation. Central retinal vein thrombosis can be a potential complication following the embolisation and operator
SC
should be aware of this unusual entity for prompt recognition and expedited management.
Fig 1. Left IMA (short thin arrows) angiograms
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Figure Legends
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Frontal (A &B) and Lateral (C&D) showing site of fistula with routes of venous drainage. Long thin arrow shows the venous sac.
Fig 3:
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Fig 2 : 3D rotational angiographic images : (A) Axial : showing site of venous sac (arrow) in the left pterygoid plates. (B) Oblique Sagittal : Showing communication (black arrow) of the venous sac (thick white arrow) with the cavernous sinus (thin white arrow) (C) Oblique axial: Showing the relationship of the venous sac (thick arrow) with the cavernous sinus (thin arrow).
Post embolization : frontal (A) and lateral (B) angiograms showing near complete cessation of shunt. Coil mass and Squid case is denoted by black arrows. Unsubtracted fluoroscopic images : Frontal (C) and Lateral (D) showing the position of the coil mass and Squid cast with no evidence of embolic agent within the cavernous sinus.
REFERENCES :
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1. Malik GM, Mahmood A, Mehta BA. Dural arteriovenous malformation of the skull base with intraosseous vascular nidus: report of two cases. J Neurosurg 1994;81:620–3. ]\ 2. Jung C, Kwon BJ, Kwon OK et al. Intraosseous cranial dural arteriovenous fistula treated
3. Jae-Hyun Shim, Seok-Mann Yoon, Jai-Joon Shim et al.
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with transvenous embolization. Am J Neuroradiol 2009;30(6):1173-7.
A Case of Intraosseous Dural
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Arteriovenous Fistulas Involving Diploic Vein Treated with Transarterial Onyx Embolization. J Korean Neurosurg Soc 2011;50 : 260-3.
Myoung Soo Kim, Chang Wan Oh, Dae Hee Han et al. Intraosseous dural arteriovenous
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4.
fistula of the skull base associated with hearing loss. J Neurosurg 2002;96:952–5. 5. Eun Suk Park, Young-Jin Jung, Jung-Ho Yun et al. Intraosseous Arteriovenous Malformation of the Sphenoid Bone Presenting with Orbital Symptoms Mimicking
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Cavernous Sinus Dural Arteriovenous Fistula: A Case Report. J Cerebrovasc Endovasc Neurosurg 2013;15(3):251-4.
6. Geibprasert S, Pereira V, Krings T, et al. Dural arteriovenous shunts: a new classification
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of craniospinal epidural venous anatomical bases and clinical correlations. Stroke 2008;39:2783–94.
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7. Miyachi S,Izumi T,Matsubara N,Naito T,Haraguchi K,Wakabayashi T. Mechanism of the formation of dural arteriovenous fistula – the role of the emissary vein Interventional Neuroradiology 17: 195-202, 2011.
8. Gemmete Joseph, Ansari Sameer, Gandhi Dheeraj. Endovascular techniques for treatment of Carotid-Cavernous Fistula. Journal of Neuro-Opthalmology 2009; 29:62-71. 9.
Sergott RC, Grossman RI, Savino PJ et al. The syndrome of paradoxical worsening of dural-cavernous sinus arteriovenous malformations. Ophthalmology 1987;94(3):205-12.
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10.
Sia PI, Sia DI, Scroop R, Selva D. Orbital compartment syndrome following transvenous embolization of carotid-cavernous fistula. Orbit 2014;33(1):52-4.
11.
Komiyama M, Yamanaka K, Nagata Y et al. Ishikawa H. Dural carotid-cavernous sinus
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fistula and central retinal vein occlusion. A case report and review of literature. Surgical
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Neurol 1990;34:255-9.
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Highlights
Skull base osseous dural fistulae are uncommon clinical entities and fistulae centered within the sphenoid bone are very rare.
•
3D rotational angiography is helpful to ascertain the location of fistula, to delineate the route of approach and to map out the safe limit of embolisation.
•
Route of embolization should be tailored on an individual case basis depending upon the angiographic findings.
•
Central retinal vein thrombosis is a potential complication following the embolisation and operator should be aware of this unusual entity for prompt recognition and expedited management.
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•
ACCEPTED MANUSCRIPT Abbreviations:
AVF : Arterio-venous fistula DAVF: Dural arterio-venous fistula
DSA : Digital subtraction angiography 3DRA : 3 dimensional rotational angiography IMA : internal maxillary artery
SC
AMA : Accessory meningeal artery
RI PT
CRVO : Central retinal vein occlusion
AC C
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M AN U
MMA : Middle meningeal Artery
S1878-8750(16)30961-5
DOI:
10.1016/j.wneu.2016.09.104
Reference:
WNEU 4644
To appear in:
World Neurosurgery
Received Date: 28 February 2016 Revised Date:
24 September 2016
Accepted Date: 26 September 2016
Please cite this article as: Mohimen A, Kumar S, Jayadevan ER, Skull Base Osseous Arterio-venous fistula – a rare clinical entity : Case report and Literature Review, World Neurosurgery (2016), doi: 10.1016/j.wneu.2016.09.104. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Title: Skull Base Osseous Arterio-venous fistula – a rare clinical entity : Case report and Literature
RI PT
Review.
ABSTRACT
SC
Purpose
To describe a rare clinical entity of intra-osseous skull base arterio-venous fistula managed with
M AN U
transvenous fistula embolization. Case details
57 year old lady presented with complaints of headache and episodic tinnitus with progressive left sided visual deterioration. Cross sectional imaging of the head revealed multiple vascular
TE D
channels in the sphenoid bone and in bilateral masticator spaces. Catheter angiography showed presence of a large osseous arterio-venous fistula (AVF) epicentered in the body of sphenoid and left pterygoid plates with arterial feeders from bilateral external carotid arteries and venous
EP
drainage. She was managed by transvenous coil and liquid embolic agent (Squid) embolization
AC C
of the venous sac with significant reduction of shunt. In the post procedure period the patient developed paradoxical worsening of symptoms due to central retinal Vein occlusion (CRVO). Conclusion
Skull base osseous fistulae are uncommon clinical entities and fistulae centered within the sphenoid bone are very rare. The aim of this report was to highlight management issues associated with such a case and review the available literature on the subject.
ACCEPTED MANUSCRIPT
INTRODUCTION: Skull base arterio-venous fistulae (AVF) with the site of fistula located within the bone are an
RI PT
uncommon set of clinical entities, described in literature only in small case series. The entity, initially described by Malik et al in 1994, is characterised by the presence of nidus within the bone, unlike the classical dural fistula where the nidus is located within the dura or sinus wall(1).
SC
The clinical presentation is variable and depends on the location of fistula and pattern of venous drainage. Various treatment approaches such as transarterial or transvenous embolization and
M AN U
surgical techniques have been described in the literature (2-5). Due to rarity of reports, a standardized approach to these lesions have not been determined. We encountered a patient with an osseous AVF within the sphenoid bone presenting with clinical features similar to indirect carotidocavernous fistula. The fistula was managed successfully with trans-venous coiling and embolization with liquid embolic agent (LED) Squid (Embofru ,Switzerland). In the
TE D
postoperative period, she developed worsening of ocular symptoms which warranted active ophthalmological intervention.
EP
In this report, we highlight the imaging features and therapeutic options of this uncommon entity along with a brief review of the available literature.
AC C
CASE REPORT:
A 50 year old lady presented with complaints of slowly progressing holocranial headache and episodic tinnitus of 6 months duration along with mild progressive visual deterioration in the left eye of 2 months duration. Clinical examination showed left sided visual acuity of 6/36 with left sided temporal hemianopia. Left temporal bruit was appreciated. MRI and CT scan of the head showed multiple vascular channels within the sphenoid bone and in bilateral masticator spaces
ACCEPTED MANUSCRIPT
suggestive of a skull base arterio-venous fistula (AVF). She underwent a digital subtraction angiogram (DSA) which confirmed the presence of a large osseous AVF epicentered in the body of the sphenoid and the left pterygoid plates. Arterial supply was from terminal branches of the
RI PT
internal maxillary artery (IMA), middle meningeal arteries (MMA) and deep temporal arteries (figure1). Venous shunting was noted into a large venous sac located within the pterygoid plates. Subsequent venous egress was noted into multiple veins into the cavernous sinuses bilaterally
SC
and into the pterygoid venous plexus. There was no evidence of cortical venous reflux or drainage via ophthalmic veins. Since, the nidus was extensive and the feeding arteries to the
M AN U
nidus were not clearly defined, she was planned for transvenous embolization. A 3DRA was obtained to delineate the access to the venous sac (figure2), which clearly demonstrated the communicating of the sac with the cavernous sinus. The venous sac was accessed from the left IJV through the left cavernous sinus using two micro catheters (Echelon 10,Covidien /
TE D
Medtronics) over a Traxcess wire (Microvention, Tustin, California,U.S.) and the sac was progressively occluded with coils and liquid embolic agent (LED) Squid 18 with near complete obliteration of the sac and near total fistula obliteration (figure 3). Two microcatheters were used
EP
to ensure that embolization could be continued in case of inadvertent prolapse of one of the catheters from the venous sac. The entry of venous sac into the cavernous sinus and was marked
AC C
in the monitor to avoid any inadvertent migration of embolic material into the sinus. In the immediate postoperative period she had significant resolution of tinnitus and headache. However on the second postoperative day, she complained of left sided visual deterioration. Ophthalmology evaluation revealed visual acuity of 6/60 with corneal edema, conjunctival congestion and cotton wool spots in the retina suggestive of central retinal vein occlusion (CRVO). She was managed conservatively with topical anti-glaucoma medications and a follow
ACCEPTED MANUSCRIPT
up ophthalmological evaluation after 2 weeks revealed intra-ocular pressure (IOP) of 34 mmHg on the left eye with neovascularisation of the left iris secondary to CRVO. She subsequently underwent two sittings of panretinal laser photocoagulation. On clinical follow up after 3
RI PT
months, her initial symptoms had subsided with visual acuity being static at 6/60. IOP was controlled at 20 mm Hg and retinal examination revealed regression of neovascularisation. The tinnitus and headache resolved completely and her visual status remained static on serial clinical
SC
follow up. Patient declined consent for follow up check angiography
M AN U
DISCUSSION:
Skull base osseous AVF are rare clinical entities with a handful of case series described hitherto in literature. There is considerable discrepancy with regard to the nomenclature of these entities and the protocols for planning appropriate treatment. Pure intra-osseous spontaneous AV shunts
TE D
were first described in 2 cases by Malik et al in 1994(1). The subsequent reports / case series and the management strategies have been detailed as per table 1. The 10 previously reported cases (1-5) have shown no specific gender predilection. The mean age of presentation was in the
EP
5th -6th decades with 2 cases reported presenting in the 2nd decade. Tinnitus (with headache) was the commonest clinical presentation with two patients presenting with hearing loss and one
AC C
patient with orbital congestive symptoms. While some authors (1,5) have named these entities as arterio-venous malformations (AVM), others have used the term AVF (2-4). There was no definied nidus evident in angiograms or 3D angiographic analysis and hence we assume that these lesions are mostly AVF. In addition, although they are anatomically distinct and confined to osseous space, embryologically, the shunts sharing a common involvement of the cranial dura, extra-dural space and the adjacent
ACCEPTED MANUSCRIPT
calvarial bone have been categorized as dural arteriovenous fistula (DAVF) (6). The etiology of purely osseous fistula is conjectural and may be similar to the development of DAVF. Inflammatory reaction secondary to venous thrombosis is posited as one of the inciting factor
RI PT
leading to DAVF formation. Thrombosis of dural sinus or emissary veins are speculated in the development of DAVF (7). Similarly, thrombosis of diploic vein induced by paranasal sinus inflammation or skull base infective process could possibly trigger inflammatory processes
Author / Year Age Sex(M/F)
1.
Malik et al / 1. 48y / M 1994 (1) 2. 49y / F
/ Clinical Features
Tinnitus with headache (both cases)
No of Nomenclature Cases
Site
2
Foramen Magnum 1. Surgery. 2. Trans-arterial -2
M AN U
Sl No
SC
which would ultimately lead to the formation of osseous fistula.
AVM
Management
embolization followed surgery.
by
Kim et al (2) 15y/M
Tinnitus, 1 headache, Hearing loss
AVF
Petrous and jugular Transvenous embolization foramen
Coil
3.
Jung et al Mean age : (3) 58.6 years; (range, 15– 82y)
Tinnitus 6 (commonest) Hearing loss – 1 case Diplopia – 1 case
AVF
Transvenous Clivus -2 embolization Petrous apex-1 Hypoglossal canal -4
coil
Tinnitus with headache
1
AVF
Parietal Bone
Trans-arterial LED (Onyx) embolization
1
AVM
Sphenoid
Trans-arterial LED (Onyx) embolization
AVF
Sphenoid
Transvenous coil & LED (SQUID) embolization
EP
TE D
2.
M:F- 4:2 Shim et al / 46y/F 2011 (4)
5.
Park et al / 43y/F 2013 (5)
Headache, orbital chemosis, proptosis
6.
Present Case
Tinnitus with 1 visual loss
AC C
4.
50y/F
ACCEPTED MANUSCRIPT
Table 1 : Summary of reports of Skull Base Osseous AVF in Literature.
Surgical as well as endovascular techniques have been described to treat these pure osseous
RI PT
fistulas. The exact localization of the fistula becomes important while planning surgical options as significant haemorrhage can be expected during the procedure and obliteration of this fistula requires complete exposure of the affected bone (1). Endovascular approaches include
SC
transarterial and transvenous obliteration of the nidus or venous sac using coils or liquid embolization agents. Following the initial report by Malik et al, subsequent management of these
M AN U
fistulas were performed by endovascular transarterial or transvenous techniques (2-5). To achieve complete cure by endovascular approach, it is essential to obliterate the nidus and or the draining vein at the shunt site completely (8). The access route is chosen considering several parameters such as easy accessibility, risk of cranial nerve injuries and presence of dangerous
TE D
intracranial-extracranial anastomoses. In our case, there was extensive involvement of the sphenoid bone with feeders from meningeal branches of external and internal carotid arteries ,hence transarterial embolisation of the fistula was not considered appropriate as the risk of
EP
cranial nerve injuries and percolation of liquid embolization agent via collaterals into the intracranial circulation was high. Transvenous approach could not be clearly delineated on
AC C
conventional angiography due to high shunt flow and overlap of multitude primary draining vein with the nidus and hence, 3DRA was performed to study the draining pattern of the fistula. 3DRA clearly demonstrated site of fistula and the draining venous sac communicating with the cavernous sinus through a venous channel This vein was subsequently used for accessing the fistula. It also helped to delineate the safe limit of permissable reflux, to avoid inadvertent occlusion of cavernous sinuses, which drain normal brain parenchyma. Initial coils were
ACCEPTED MANUSCRIPT
deployed to reduce the amount of liquid embolic agent and we used two microcatheters to preserve the access in the event of microcatheter kickback.
RI PT
Interestingly, the patient developed CRVO in the postoperative period, although significant reflux into the superior ophthalmic vein (SOV) was not noted in the initial angiograms. Paradoxical worsening of symptoms following the treatment of indirect carotico-cavernous
SC
fistulae (CCF) has been described and it has been postulated to be due to the development of thrombosis within the SOV with thrombus extension into the central retinal vein, resulting in
M AN U
CRVO (9-11). If the anastomotic communication with choroidal veins is compromised, it may result in severe retinal ischemia and hemorrhagic retinopathy (11). In our case, even though the shunt flow was very high, it was promptly decompressed by cavernous sinuses and pterygoid plexus.In such situation, the SOV flow, even if not directly visualized, would be expected to be in antegrade direction, towards the cavernous sinus due to the venturi effect caused by high flow
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situation. Stagnant flow within the SOV following shunt obliteration would have precipitated thrombosis and retrograde propagation into central retina vein would have resulted CRVO in our patient. It is important to identify this complication early, so that appropriate therapeutic
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measures such as control of intraocular pressure and possibly, anticoagulation can be considered
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to reduce or limit the extent of ocular injury. Literature review of previously reported cases treated with embolization showed complete improvement of tinnitus and headache (similar to our case). The two patients who had presented with hearing loss had no improvement after treatment (2,3). Complete immediate / delayed angiographic shunt obliteration was noted in 10 of the previous 11 cases. These results confirm that endovascular options are mainstay of treatment for managing unusual osseous fistulas and additional imaging with 3D angiograms can be a useful tool for the interventionist to decide on appropriate treatment strategy.
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CONCLUSION Skull base osseous dural fistulae are uncommon clinical entities and fistulae centered within the
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sphenoid bone are very rare. 3D rotational angiography is helpful to ascertain the location of fistula, to delineate the route of approach and to map out the safe limit of embolisation. Central retinal vein thrombosis can be a potential complication following the embolisation and operator
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should be aware of this unusual entity for prompt recognition and expedited management.
Fig 1. Left IMA (short thin arrows) angiograms
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Figure Legends
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Frontal (A &B) and Lateral (C&D) showing site of fistula with routes of venous drainage. Long thin arrow shows the venous sac.
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Fig 2 : 3D rotational angiographic images : (A) Axial : showing site of venous sac (arrow) in the left pterygoid plates. (B) Oblique Sagittal : Showing communication (black arrow) of the venous sac (thick white arrow) with the cavernous sinus (thin white arrow) (C) Oblique axial: Showing the relationship of the venous sac (thick arrow) with the cavernous sinus (thin arrow).
Post embolization : frontal (A) and lateral (B) angiograms showing near complete cessation of shunt. Coil mass and Squid case is denoted by black arrows. Unsubtracted fluoroscopic images : Frontal (C) and Lateral (D) showing the position of the coil mass and Squid cast with no evidence of embolic agent within the cavernous sinus.
REFERENCES :
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1. Malik GM, Mahmood A, Mehta BA. Dural arteriovenous malformation of the skull base with intraosseous vascular nidus: report of two cases. J Neurosurg 1994;81:620–3. ]\ 2. Jung C, Kwon BJ, Kwon OK et al. Intraosseous cranial dural arteriovenous fistula treated
3. Jae-Hyun Shim, Seok-Mann Yoon, Jai-Joon Shim et al.
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with transvenous embolization. Am J Neuroradiol 2009;30(6):1173-7.
A Case of Intraosseous Dural
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Arteriovenous Fistulas Involving Diploic Vein Treated with Transarterial Onyx Embolization. J Korean Neurosurg Soc 2011;50 : 260-3.
Myoung Soo Kim, Chang Wan Oh, Dae Hee Han et al. Intraosseous dural arteriovenous
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fistula of the skull base associated with hearing loss. J Neurosurg 2002;96:952–5. 5. Eun Suk Park, Young-Jin Jung, Jung-Ho Yun et al. Intraosseous Arteriovenous Malformation of the Sphenoid Bone Presenting with Orbital Symptoms Mimicking
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Cavernous Sinus Dural Arteriovenous Fistula: A Case Report. J Cerebrovasc Endovasc Neurosurg 2013;15(3):251-4.
6. Geibprasert S, Pereira V, Krings T, et al. Dural arteriovenous shunts: a new classification
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of craniospinal epidural venous anatomical bases and clinical correlations. Stroke 2008;39:2783–94.
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7. Miyachi S,Izumi T,Matsubara N,Naito T,Haraguchi K,Wakabayashi T. Mechanism of the formation of dural arteriovenous fistula – the role of the emissary vein Interventional Neuroradiology 17: 195-202, 2011.
8. Gemmete Joseph, Ansari Sameer, Gandhi Dheeraj. Endovascular techniques for treatment of Carotid-Cavernous Fistula. Journal of Neuro-Opthalmology 2009; 29:62-71. 9.
Sergott RC, Grossman RI, Savino PJ et al. The syndrome of paradoxical worsening of dural-cavernous sinus arteriovenous malformations. Ophthalmology 1987;94(3):205-12.
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Sia PI, Sia DI, Scroop R, Selva D. Orbital compartment syndrome following transvenous embolization of carotid-cavernous fistula. Orbit 2014;33(1):52-4.
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Komiyama M, Yamanaka K, Nagata Y et al. Ishikawa H. Dural carotid-cavernous sinus
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fistula and central retinal vein occlusion. A case report and review of literature. Surgical
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Neurol 1990;34:255-9.
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Highlights
Skull base osseous dural fistulae are uncommon clinical entities and fistulae centered within the sphenoid bone are very rare.
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3D rotational angiography is helpful to ascertain the location of fistula, to delineate the route of approach and to map out the safe limit of embolisation.
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Route of embolization should be tailored on an individual case basis depending upon the angiographic findings.
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Central retinal vein thrombosis is a potential complication following the embolisation and operator should be aware of this unusual entity for prompt recognition and expedited management.
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ACCEPTED MANUSCRIPT Abbreviations:
AVF : Arterio-venous fistula DAVF: Dural arterio-venous fistula
DSA : Digital subtraction angiography 3DRA : 3 dimensional rotational angiography IMA : internal maxillary artery
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AMA : Accessory meningeal artery
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CRVO : Central retinal vein occlusion
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MMA : Middle meningeal Artery