Venous Hypertension As the Cause of Intracranial Hypertension in Patients with Transverse Sinus Dural Arteriovenous Fistula

Home , Sigmoid sinus, Transverse sinuses

Original Contribution

Venous Hypertension as the Cause of Intracranial Hypertension in Patients With Transverse Sinus Dural Arteriovenous Fistula

Rebekah M. Ahmed, MBBS(Hons), FRACP, Bryan Khoury, MBBCh, FRANZCR, Mark Wilkinson, MBChB, FRANZCR, Geoffrey D. Parker, MBBS, FRANZCR, G. Michael Halmagyi, MD, FRACP

Abstract: We describe 2 patients with transverse sinus CASE REPORTS dural arteriovenous fistulas (DAVFs) who presented with headache and papilledema due to intracranial hypertension. It has been proposed, but never proven, that venous Case 1 hypertension causes the intracranial hypertension in DAVF. The data from our patients support this hypothesis. An A 51-year-old man presented with a 4-month history of left additional factor leading to intracranial hypertension could pulsatile tinnitus. He had an easily palpable left occipital be stenosis of the fellow transverse sinus. artery, a bruit over the left mastoid, and moderately severe, – bilateral papilledema. Visual acuity was 20/20 in each eye, Journal of Neuro-Ophthalmology 2013;33:102 105 fi doi: 10.1097/WNO.0b013e318250575b and visual elds demonstrated enlarged blind spots without © 2012 by North American Neuro-Ophthalmology Society peripheral field constriction. MRA and magnetic resonance venogram (MRV) with auto-triggered elliptic centric ordered (ATECO) sequences (8) (Fig. 1A) showed occlusion of the left transverse and sigmoid sinuses, with an associated D ural arteriovenous fistula (DAVF) of one transverse DAVF; the occipital artery was dilated and there was subtle sinus can cause intracranial hypertension with papil- cortical venous reflux (Cognard grade IIB) (9). Arteriogra- ledema but without ventriculomegaly, simulating idiopathic phy (Fig. 1B) confirmed a DAVF of the left transverse sinus – intracranial hypertension and leading to vision loss (1 5). with arterial supply from a large transmastoid occipital Cerebral venous sinus hypertension leading to decreased branch of the external carotid artery, the left middle men- fl cerebrospinal uid (CSF) absorption has been proposed ingeal artery, the left internal carotid artery via the – (3 6), although never been proven to be the mechanism. meningo-hypophyseal trunk, and from both vertebral We report 2 patients with intracranial hypertension and arteries via suboccipital branches. The left superior sigmoid DAVFs of one transverse sinus, in whom intracranial sinus was severely attenuated with multiple venous chan- hypertension resolved after embolization of the DAVF. nels, suggesting previous thrombosis. Venous sinus pressure We found that in addition to the DAVF of one transverse measurements were recorded before and after embolization sinus, there was a stenosis of the fellow transverse sinus. We (Table 1). propose that in these patients the lack of even one func- The patient underwent 2 arterial embolization procedures tioning transverse sinus allowed intracranial hypertension to with Onyx. After the second, a left carotid arteriogram dem- develop (7). onstrated no reflux in to cortical veins (Cognard grade IIA). Five months after embolization, the patient still had papilledema but no longer had tinnitus. Lumbar puncture Departments of Neurology (RMA, GMH) and Radiology (BK, MW, showed an opening pressure of 350 mm H20 with normal GDP), Royal Prince Alfred Hospital, Camperdown, Sydney, Australia. CSF contents. Arteriography showed no change in the The authors report no conflict of interest. DAVF. Venography demonstrated that the left transverse Address correspondence to Rebekah M. Ahmed, Department of Neu- rology,RoyalPrinceAlfredHospital,MissendenRoad,Camperdown, sinus was occluded, and there was a swollen arachnoid gran- Sydney, NSW, Australia 2050; E-mail:[email protected] ulation in the right transverse sinus impairing venous flow

102 Ahmed et al: J Neuro-Ophthalmol 2013; 33: 102-105

FIG. 1. Case 1. A, MRA with ATECO sequences (8) shows extensive, arterialized flow into a very irregular transverse/sigmoid sinus (long arrow) by a dural arteriovenous fistulous channel; left occipital artery (arrowhead); left internal carotid artery (small arrow). B, Late arterial phase from left external carotid artery injection shows extensive dural arteriovenous fistulous channels (black arrow) entering the left transverse/sigmoid sinus with rapid retrograde flow across the torcular into the right transverse/sigmoid sinus (white arrow). The distal left sigmoid sinus is markedly narrowed, with prominent flow into the left vertebral venous plexus (arrowheads). C, Onyx cast within the left transverse/sigmoid sinus and dural channels (white arrow) and coils within the proximal left transverse sinus (black arrow).

(pressure gradient: 25 mm Hg). Anterior sagittal sinus pres- Case 2 sure was elevated at 54 mm Hg. An 85-year-old woman with a long history of left pulsatile Six months after arterial embolization, the DAVF was tinnitus was found to have papilledema. Her visual acuity embolized via the right transverse sinus, with 11 hydrocoils was 20/30 in each eye, and visual fields showed enlarged placed in the stump of the left transverse sinus (Fig. 1C). blind spots but no peripheral constriction. MRV disclosed Superior sagittal sinus and torcular pressure decreased to a DAVF draining into the left transverse sinus and distal 29 mm Hg, and the pressure gradient across the arachnoid occlusion of the left sigmoid sinus, with no filling of the left granulation of the right transverse sinus decreased to 5 mm Hg. internal jugular vein. The patient’s papilledema resolved. Arteriography (Fig. 2A) demonstrated a DAVF involving The most recent venogram documented that venous the left transverse sinus with no cortical reflux, and drainage sinus pressure remained stable with a superior sagittal sinus across the torcular into the right transverse sinus and right pressure of 27 mm Hg and a pressure gradient across the internal jugular vein (Cognard grade IIA). Arterial supply was right transverse sinus of 7 mm Hg (Table 1). The patient predominantly via the left occipital and middle meningeal remains well without headache or papilledema. branches, with lesser supply via suboccipital and posterior

TABLE 1. Venous Sinus Pressures Recorded Before and After Embolization of DAVF of Transverse Sinus Case 1 Case 2 Post-embolization Post-embolization Pre-embolization 1 Month 9 MonthsPre-embolization Immediate 4 Months

ASSS 53 29 27 38 21 16 MSSS 54 29 27 41 21 16 PSSS 54 29 26 42 21 15 Torcular 52 29 24 40 21 15 PTS 52 28 22 43* 21 14 Mid TS 47* 27* 22* 21 12 ATS 42 22* 15 15* 21 11 Sup. sig. sinus 22* 21 15* 19 12 9 Inf. sig. sinus 19 21 14 15 12 9 Jugular bulb 19 21 11 14 12 8 Internal jugular 18 22 9 11 11 7 Right atrium 17 17 7 9 9 6

All pressure measurements are expressed in millimeters of mercury. *Gradient across stenosis. ASSS, anterior superior sagittal sinus; ATS, anterior transverse sinus; MSSS, mid-superior sagittal sinus; PSSS, posterior superior sagittal sinus; PTS, posterior transverse sinus; sup. sig. sinus, superior sigmoid sinus; inf. sig. sinus, inferior sigmoid sinus.

Ahmed et al: J Neuro-Ophthalmol 2013; 33: 102-105 103

FIG. 2. Case 2. A, Arteriogram demonstrates left transverse sinus dural arteriovenous ﬁstula. B, Venogram shows high venous pressure throughout the venous sinuses before embolization and narrowing of the right transverse sinus (arrows). C, Manometry of the venous sinuses reveals a pressure gradient of 28 mm Hg (arrow) across stenosis of the right transverse sinus. D, Four months after embolization, venogram shows normal venous pressures throughout the sinuses and less narrowing of the right transverse sinus. ASSS, anterior superior sagittal sinus; ATS, anterior transverse sinus; MSSS, mid- superior sagittal sinus; PSSS, posterior superior sagittal sinus; PTS, posterior transverse sinus; RA, right atrium; RIJV, right inferior jugular vein; R. Inf. Sig., right inferior sigmoid sinus; R. Sup. Sig., right superior sigmoid sinus.

meningeal branches of the vertebral arteries and meningo- Hg, and the pressure gradient across the stenosis in the right hypophyseal tentorial branches. There was no drainage into transverse sinus resolved (Table 1). The patient developed the left sigmoid sinus or left jugular vein. Venography dem- a small intracerebral occipital hemorrhage but made a full onstrated a narrowing of the right transverse sinus together recovery. Papilledema and pulsatile tinnitus resolved. with rapid inflow of unopacified blood via the fistula. The Four months later, venography showed normal venous narrowing was felt to be due to a combination of swelling of sinus pressures (Table 1) and narrowing of the right trans- an arachnoid granulation and elevated intracranial pressure. verse sinus had improved (Fig. 2D). Superior sagittal sinus pressure measured 41 mm Hg (Fig. 2B, 2C; Table 1), with an abrupt drop to 15 mm Hg across the DISCUSSION narrowed segment of the right transverse sinus (Fig. 2C). The DAVF was embolized with Onyx via a transarterial It has been proposed that intracranial hypertension in the approach. Superior sagittal sinus pressure decreased to 21 mm setting of a transverse sinus DAVF is the result of a decreased

104 Ahmed et al: J Neuro-Ophthalmol 2013; 33: 102-105

CSF absorption secondary to venous hypertension (3,4,10). ophthalmic evaluation should be performed, including Our 2 cases support this concept. In our first patient, after visual acuity, visual fields, and funduscopy. Embolization embolization, venous pressure remained mildly elevated due should be considered if there is any indication of risk of to the ongoing arterial supply to the DAVF and narrowing visual loss. of the right transverse sinus. Yet, treatment was sufficient to resolve the patient’s tinnitus and papilledema. In our second patient, embolization not only terminated flow in ACKNOWLEDGMENT the DAVF but also lessened stenosis in the contralateral Dr Steve Reddel referred the second patient. transverse sinus. Again, the patient’s symptoms resolved as did the papilledema and the venous hypertension. REFERENCES It has been shown that the lack of even one functioning 1. Johnston I, Hawke S, Halmagyi GM, Teo C. The pseudotumor transverse sinus may lead to venous hypertension and syndrome. Disorders of cerebrospinal fluid circulation causing intracranial hypertension without ventriculomegaly. Arch intracranial hypertension (7,11). We propose that this also Neurol. 1991;48:740–747. might be true in transverse sinus DAVFs causing intracra- 2. Cockerell OC, Lai HM, Ross-Russell RW. Pseudotumour cerebri fi associated with arteriovenous malformations. Postgrad Med J. nial hypertension, given the ndings in our 2 patients. – fl 1993;69:637 640. Adding to the increase in venous pressures was the ow 3. Cognard C, Casasco A, Toevi M, Houdart E, Chiras J, of arterialized blood into the transverse sinuses, leading to Merland JJ. Dural arteriovenous fistulas as a cause of further venous hypertension and intracranial hypertension intracranial hypertension due to impairment of cranial venous outflow. J Neurol Neurosurg Psychiatry. 1998;65:308–316. through decreased CSF absorption at the arachnoid villi. By 4. Silberstein P, Kottos P, Worner C, Glenn D, Shnier R, Davies M, embolizing the DAVFs, the venous hypertension improved, Halmagyi GM, Hersch M. Dural arteriovenous fistula causing as did the intracranial hypertension and papilledema. pseudotumour cerebri syndrome in an elderly man. J Clin Neurosci. 2003;10:242–243. We propose that if a patient has a DAVF of one trans- 5. Van den Bergh R, Dralands G, Crolla D, Van den Bergh P. verse sinus and the other transverse sinus is functioning, Pseudotumor cerebri due to intracranial arteriovenous significant venous hypertension and subsequent intracranial malformation. Clin Neurol Neurosurg. 1980;82:119–125. 6. Kuhner A, Krastel A, Stoll W. Arteriovenous malformations of hypertension will not develop. Cognard et al (3) in their the transverse dural sinus. J Neurosurg. 1974;40:322–329. review of DAVFs leading to intracranial hypertension 7. Ahmed R, Wilkinson M, Parker G, Thurtell M, Macdonald J, reported that only 4 of 13 patients had normal venous McCluskey P, Allan R, Dunne V, Hanlon M, Owler BK, Halmagyi GM. Transverse sinus stenting for idiopathic sinuses. However, the authors did not look for stenosis intracranial hypertension: a review of 52 patients and of model of the contralateral sinus nor obtain pressure gradient meas- predictions. AJNR Am J Neuroradiol. 2011;32:1408–1414. urements. It was reported that all patients had abnormal 8. Farb R, Scott J, Willinsky R, Montanera J, Wright G, fl terBrugge KG. Intracranial venous system: gadolinium- cerebral venous ow. enhanced three-dimensional MR venography with auto- DAVFs with reflux into cortical veins (Cognard type triggered elliptic centric-ordered sequence—initial experience. IIB) pose great risk for hemorrhage and focal neurological Radiology. 2003;226:203–209. fl 9. Cognard C, Gobin YP, Pierot L, Bailly AL, Houdart E, Casasco A, damage (5). We believe that a DAVF with anterograde ow Chiras J, Merland JJ. Cerebral dural arteriovenous fistulas: (Cognard type I) and reflux into the affected sinus (Cognard clinical and angiographic correlation with a revised type IIA) are also not “benign” and may cause venous classification of venous drainage. Radiology. 1995;194:671–680. hypertension with papilledema and potential vision loss. 10. Lamas E, Lobato RD, Esparza J, Escudero L. Dural posterior Patients having arteriography for investigation of DAVFs fossa AVM producing raised sagittal sinus pressure. J should be considered for venography and manometry. In Neurosurg. 1977;46:804–810. fi 11. King JO, Mitchell PJ, Thomson KR, Tress BM. Cerebral patients where venous hypertension is identi ed, especially venography and manometry in idiopathic intracranial in the setting of only one functioning transverse sinus, a full hypertension. Neurology. 1995;45:2224–2228.

Ahmed et al: J Neuro-Ophthalmol 2013; 33: 102-105 105