Torcular Dural Arteriovenous Fistula Treated Via Stent Placement and Angioplasty in the Affected Straight and Transverse Sinuses: Case Report

case report J Neurosurg 122:1208–1213, 2015

Torcular dural arteriovenous fistula treated via stent placement and angioplasty in the affected straight and transverse sinuses: case report

Shigeki Takada, MD, Fumiaki Isaka, MD, PhD, Takuya Nakakuki, MD, Yuto Mitsuno, MD, and Takaaki Kaneko, MD, PhD

Department of Neurosurgery, Hikone Municipal Hospital, Hikone, Japan

The successful obliteration of torcular dural arteriovenous fistula (DAVF) with a diffuse shunt in the affected sinus may require complex treatment strategies. Therapeutic goals include the preservation of normal venous drainage and complete obliteration of shunt flow. The authors report the case of a torcular DAVF. The treatment of this type of AVF may require a combined approach with transarterial and transvenous embolization, open surgery, or radiosurgery and is associated with many problems. Stent placement and angioplasty in the affected sinus result in compression of the fistulous dural wall of the sinus and decrease shunt flow. In cases in which there is a diffuse shunt in the affected sinus and no evident shunt point, such as in AVFs involving venous pouches and parasinuses, sealing the fistula orifice with self-expandable stents and angioplasty (balloon inflation) is considered the best treatment option to preserve normal cerebral venous sinus drainage and obliterate shunt flow. In such cases, the authors recommend using one or more self-expandable and closed-cell stents and using angioplasty to avoid endoleakage into the gap between the stent graft and the vessel wall. http://thejns.org/doi/abs/10.3171/2014.12.JNS141374 Key Words torcular dural arteriovenous fistula; stent placement; angioplasty; vascular disorders

ural arteriovenous fistulas (DAVFs) are relatively details in a case of torcular DAVF in which the complete uncommon (incidence of 0.15–0.16 cases/100,000 obliteration of shunt flow was achieved by stent placement people/year)1,2 and represent approximately 10%– and angioplasty. We describe the technical details of this 15%D of all intracranial arteriovenous shunts.10 The clinical case. course of DAVF is variable, ranging from asymptomatic to symptomatic presentations, with an aggressive presen- Case Report tation consisting of venous hypertension and neurological deficit in patients with high-flow shunts. In patients with History and Examination cortical venous reflux, intracerebral hemorrhage (ICH) A 64-year-old man with progressive dementia (Mini- may be the initial symptom. The presence of deep venous Mental State Examination [MMSE] Score 13) was referred drainage causes venous infarction, resulting in ICH and to our department with the diagnosis of torcular DAVF. dementia. Most DAVFs are treated via an endovascular Six years earlier, he had undergone transarterial and trans- approach; however, successful obliteration of complex venous embolization for a cavernous DAVF that presented DAVFs may require a combined approach involving open with headache, conjunctival injection, and exophthalmos; surgery, endovascular treatment, and radiosurgery. Rou- complete obliteration of the fistula was achieved. Follow- tine endovascular techniques include transarterial and up angiography performed 1 year later confirmed com- transvenous embolization by coil placement and injec- plete obliteration of the cavernous DAVF; however, it also tion of particles or liquid embolic material as an adjunct revealed a new torcular DAVF, which was asymptomatic to surgical treatment or as a curative treatment. In some and without cortical and deep venous reflux (Borden Type patients, however, the use of these techniques is impos- I). Therefore, the patient was kept under observation. Dur- sible given the associated problems. Here we describe the ing the follow-up period, he presented at the emergency

Abbreviations DAVF = dural arteriovenous fistula; ECA = external carotid artery; ICA = internal carotid artery; ICH = intracerebral hemorrhage; MMSE = Mini-Mental State Examination; VA = vertebral artery. submitted June 20, 2014. accepted December 18, 2014. include when citing Published online February 13, 2015; DOI: 10.3171/2014.12.JNS141374. Disclosure The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.

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Unauthenticated | Downloaded 09/27/21 04:09 PM UTC Dural arteriovenous fistula treated by stent placement and angioplasty room with left paresis and sensory disturbance. Com- puted tomography scanning on admission demonstrated a right thalamic hemorrhage (Fig. 1). Cerebral angiography revealed a torcular DAVF fed by multiple meningeal arteries with cortical and deep venous reflux and venous congestion (Borden Type II). Transarterial embolization was performed several times, and open surgery (sinus isolation) was performed once. Although flow in the DAVF decreased after these treatments, complete obliteration was not achieved. In addition, the multiple treatments administered caused skin flap ulceration. Thus, the skin was reconstructed with a latissimus dorsi musculocutaneous flap (anastomosis: the superficial temporal artery with the dorsal thoracic artery, the superficial temporal vein with the dorsal thoracic vein). After these therapies, cognitive function improved and venous reflux decreased. Howev- er, during the follow-up period, dementia worsened over time. We performed FLAIR MRI, which showed hyper- intensities in bilateral thalami, indicating cerebral edema (Fig. 2A and B). In addition, T2*-weighted images showed hypointensities in bilateral thalami, which indicated previ- ous hemorrhage and microbleeds (Fig. 2C and D). Angiographic Findings Digital subtraction angiography demonstrated multiple Fig. 2. Axial FLAIR images (A and B) showed hyperintensity in bilateral arteries feeding the torcular DAVF from the intracranial thalami, which indicated cerebral edema. Axial T2*-weighted images (C and extracranial circulations. Cerebral angiography re- and D) showed hypointensity in bilateral thalami, which indicated previ- vealed increased shunt flow along with cortical and deep ous hemorrhage and microbleeds. venous reflux. Contrast injection in the right internal carotid artery (ICA) revealed filling of the DAVF from the filling of the DAVF from the middle meningeal arteries tentorial arteries and posterior cerebral arteries. Contrast and superficial temporal arteries. Contrast injection in the injection in the left ICA revealed filling of the DAVF right vertebral artery (VA) revealed filling of the DAVF from the tentorial arteries. Contrast injection in the right from the posterior cerebral arteries. Antegrade venous external carotid artery (ECA) demonstrated filling of the drainage was directed toward the right transverse sinus, DAVF from the superficial temporal arteries and occipital and retrograde venous drainage was directed toward the arteries. Contrast injection in the left ECA demonstrated deep venous system through the straight sinus. Markedly dilated cortical and deep veins and right transverse sinus stenosis were observed (Fig. 3). Operation The patient and his family provided written informed consent for the procedure, which was performed under general anesthesia. The right femoral artery was accessed using a 5-Fr sheath, and a 4-Fr diagnostic catheter was placed in the left ECA to guide contrast injections. The right jugular vein was accessed with an 8-Fr sheath, and an 8-Fr guiding catheter (Brite Tip straight guiding catheter, Cordis, Johnson & Johnson) was introduced over a hydrophilic 0.035-in soft-tip angled guidewire and was navigated into the right transverse-sigmoid junction. A percutaneous transluminal angioplasty balloon (3.5 × 20 mm, Ryujin Plus OTW, Terumo) was dilated at the right stenotic portion of the right transverse sinus, and a self- expanding closed stent (8 × 29 mm, Carotid Wallstent Monorail, Boston Scientific Ireland Ltd.) was deployed from the straight sinus to the right transverse sinus, covering the stenotic portion of the right transverse sinus and the affected straight sinus. Contrast injection in the left ECA still demonstrated filling of the DAVF. Therefore, to deploy another self-expanding closed stent over the first Fig. 1. Computed tomography scan obtained at presentation, demon- stent, we attempted to introduce it into the right transverse strating right thalamic hemorrhage. sinus. Because it was difficult to advance it into the right

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Fig. 3. Bilateral ECA, bilateral ICA, and right VA angiograms demonstrating a torcular DAVF. Right ECA angiograms demonstrated the DAVF feeding of the right superficial temporal artery and right occipital artery in the anteroposterior projection (early arterial phase, A) and lateral projection (early arterial phase, B). Left ECA angiograms demonstrated filling of the DAVF from the left middle meningeal artery and left superficial temporal artery in the anteroposterior projection (late arterial phase, C). Right ICA angiograms demonstrated filling of the DAVF from the right tentorial artery and right posterior cerebral artery in the anteroposterior projection (late arterial phase, D) and lateral projection (early arterial phase, E). Left ICA angiograms demonstrated filling of the DAVF from the left tentorial artery in the anteroposterior projection (late arterial phase, F). Right VA angiograms demonstrated the DAVF fed by the right posterior cerebral artery in the anteroposterior projection (late arterial phase, G). Antegrade venous drainage was directed toward the right transverse sinus, and retrograde venous drainage was directed toward the deep venous system through the straight sinus. Right VA angiograms demonstrated markedly dilated vein of Galen, internal occipital vein, and internal cerebral vein in the lateral projection (venous phase, H), and left ECA angiograms demonstrated right transverse sinus stenosis in the anteroposterior projection (late arterial phase, C). Left ECA 3D angiograms demonstrated a torcular DAVF feeding of the left middle meningeal artery and left superficial temporal artery (I). transverse sinus, we replaced the straight guiding catheter DAVF; therefore, we deployed a third stent (8 × 20 mm, with an angled guiding catheter (8-Fr angled peripheral Iliac Wallstent RP, Boston Scientific Ireland Ltd.) over the guide catheter, Launcher, Medtronic). We introduced the first and second stents at the lesion of the shunt point in angled guiding catheter and the second stent (8 × 21 mm, the same manner. After successful deployment of the stent Carotid Wallstent Monorail) over the wire into the first graft, repeat balloon inflations (4.5× 20 mm, Sterling Bal- stent, pulled the guiding catheter, and deployed the sec- loon Dilation Monorail Catheter, Boston Scientific USA) ond stent over the first stent in the affected sinus. Contrast were performed to fix the stent graft to the venous sinus injection in the left ECA still demonstrated filling of the wall. Contrast injection in the bilateral ECA, ICA, and VA DAVF, but shunt flow was markedly decreased. Contrast still demonstrated filling of the DAVF, but retrograde ve- injection in the right ECA still demonstrated filling of the nous drainage was absent (Borden Type I; Fig. 4).

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Postoperative Course involving endovascular treatment (transarterial and trans- The patient was discharged on the 4th postoperative venous embolization), open surgery, and radiosurgery. day and was placed on 200 mg of cilostazol and 15 mg of However, these approaches were not applicable in the pres- rivaroxaban daily. At the 3-month follow-up, the patient’s ent case for the following reasons. 1) During transvenous neurological findings had ameliorated (MMSE Score embolization of DAVFs, in general, the venous pouches, 23). Follow-up angiography performed at that time dem- parasinuses, and affected sinus are embolized using de- onstrated normal cerebral venous drainage with in-stent tachable coils; however, it is important to preserve normal stenosis of the straight and right transverse sinuses and venous drainage. In the present case, the affected sinus was without recurrent shunt flow (Fig. 5A–D). The hyperinten- the straight sinus and the right transverse sinus near the tor- sity in bilateral thalami observed on FLAIR images had cular herophili. We wanted to accomplish complete oblit- decreased (Fig. 5E and F). eration of the DAVF and preserve normal venous drainage from the straight sinus to the right transverse sinus. 2) Dur- ing transarterial embolization using detachable coils and Discussion liquid embolic agents, if the shunt points are embolized, Abnormal arteriovenous communication located in the complete obliteration of the DAVF can be accomplished; sinus wall is generally considered to be the pathology in however, this is very difficult. Dural AVFs occasionally re- DAVFs; however, their pathogenesis is not fully under- cur because their feeding arteries have extensive collateral stood. A limited number of histological evaluations of networks. In the present case, the skin was reconstructed resected specimens have shown a constant pattern in the using a latissimus dorsi musculocutaneous flap. Transarte- architecture of the affected sinus wall. The essential ab- rial embolization can result in avascularity of the skin and normality was not a direct arteriovenous shunt to the sinus skin ulceration; thus, the procedure was not applicable in lumen; rather, it was a connection between dural arteries the present case. 3) Surgical isolation or resection of the and dural veins within the venous sinus wall.4,11 fistulous sinus is associated with a high cure rate;5 how- Dural AVFs are addressed with a multimodal approach ever, it is not always feasible and carries the risks associ-

Fig. 4. Contrast injection in the left ECA demonstrated filling of the torcular DAVF (A). After deployment of the first and second stents, shunt flow decreased (B and C). Contrast injection in the right ECA still demonstrated filling of the DAVF (D); therefore, a third stent was deployed and angioplasty was performed (E and F). Contrast injection in the right ECA (G), right ICA (H), left ECA (I), and right VA (J) still demonstrated filling of the DAVF, but retrograde venous drainage had disappeared (K).

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Fig. 5. Follow-up angiograms obtained 3 months after the procedure demonstrated normal cerebral venous drainage with moder- ate in-stent stenosis and without recurrent shunt flow (A–D). The hyperintensity observed in bilateral thalami on FLAIR images was decreased (E and F). ated with open surgery, such as blood loss, brain adhesions, of some debate. An investigation performed by Levrier et and skin flap problems. In the present case, the multiple al.6 showed that the inner endoluminal compression force treatments administered caused skin flap ulceration, and on the sinus wall is related to the stent radial force and is the skin was reconstructed with a latissimus dorsi mus- dependent on the mechanical characteristics of the stent. culocutaneous flap. We thought that open surgery would Stainless steel stents usually provide a stronger radial certainly result in skin flap troubles; therefore, we did not force than nitinol stents. These authors reported that stent consider open surgery in the present case. 4) Recent studies caliber size should be appropriate. An undersized stent on the use of stereotactic radiation therapy reported a rela- will not compress the sinus wall and will not significantly tively high occlusion rate (in approximately 60% of cases) decrease shunt flow. They also asserted that stent lengths several months after treatment, without significant compli- should be appropriate. Insufficient covering of the affect- cations;13 however, DAVF obliteration via radiosurgery is ed sinus leads to incomplete treatment. A study performed a long process. We needed to obliterate the shunt flow and by Ohara et al.12 indicated that self-expandable and closed- retrograde venous drainage as soon as possible. Therefore, cell type stents, such as the Wallstent, are suitable for the we did not consider radiosurgery in the present case. recanalization of thrombosed sinus in DAVFs because If stent placement in the affected sinus can obliterate a their radial force may also induce compression of the fis- DAVF shunt, it can decrease shunt flow immediately and tulous dural wall of the affected sinus. Choi et al.3 and preserve the straight and right transverse sinuses. Choi et Liebig et al.7 revealed that it is important to avoid blood al.3 reported the use of a stent graft to preserve venous leakage (endoleakage) into the gap between the stent graft sinus flow in a DAVF involving the dominant transverse- and the vessel wall by repeated and high-pressured bal- sigmoid junction and sigmoid sinus in a patient with hypo- loon inflation. The use of covered stents to treat a DAVF plasia of the contralateral venous sinuses and intolerable involving the transverse sinus has also been reported.3 balloon occlusion test for the ipsilateral venous sinuses. Covered stents are effective in occluding perpendicular Stent placement in the affected sinus of DAVFs and an- shunt flow to the stent strut. In the present case, we first gioplasty could compress these vessels in the sinus wall selected a self-expandable closed-cell stent, the Wallstent, and occlude the arteriovenous shunt flow hemodynami- and used 3 closed-cell stents and performed repeated an- cally. Therefore, in cases in which there is no evident gioplasty to compress them on the affected sinus wall. We shunt point, such as the venous pouches and parasinuses, did this because closed-cell stents have a smaller free-cell but there is diffuse shunt flow in the affected sinus, stent area than open-cell stents; thus, an increase in the number placement with or without angioplasty in the affected si- of closed-cell stents yielded a smaller free-cell area. We nus can be an effective treatment to occlude the DAVF and chose multiple stent placements and angioplasty rather preserve normal cerebral venous sinus drainage.3,6–9,12,15 than a covered stent or a flow diverter because it is difficult Stent selection among patients with DAVF is a matter to advance a covered stent into the right transverse sinus

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Unauthenticated | Downloaded 09/27/21 04:09 PM UTC Dural arteriovenous fistula treated by stent placement and angioplasty and straight sinus and because a flow diverter has still not lateral venous sinuses: technical case report. Neurosurgery been approved in Japan. 65:E994–E996, 2009 We attained a marked decrease in shunt flow and signif 4. Hamada Y, Goto K, Inoue T, Iwaki T, Matsuno H, Suzuki S, et al: Histopathological aspects of dural arteriovenous fistulas icant amelioration of clinical symptoms in the present case. in the transverse-sigmoid sinus region in nine patients. Neu- Another important concern during stent graft place- rosurgery 40:452–458, 1997 ment in the venous sinus is antithrombotic therapy. There 5. Kakarla UK, Deshmukh VR, Zabramski JM, Albuquerque is controversy regarding the selection and duration of an- FC, McDougall CG, Spetzler RF: Surgical treatment of tithrombotic agents. Choi et al.3 described a patient with high-risk intracranial dural arteriovenous fistulae: clinical a DAVF of the transverse sigmoid sinus treated via the outcomes and avoidance of complications. Neurosurgery placement of a balloon-expandable and covered stent graft 61:447–459, 2007 6. Levrier O, Métellus P, Fuentes S, Manera L, Dufour H, in the affected venous sinus. In that case, premedication Donnet A, et al: Use of a self-expanding stent with balloon was not administered because the patient underwent emer- angioplasty in the treatment of dural arteriovenous fistulas gency treatment. After the procedure, the patient received involving the transverse and/or sigmoid sinus: functional and 100 mg of aspirin and 75 mg of clopidogrel daily. In ad- neuroimaging-based outcome in 10 patients. J Neurosurg dition, low-molecular-weight nadroparin calcium (2850 104:254–263, 2006 IU/0.3 ml) was subcutaneously administered twice a day 7. Liebig T, Henkes H, Brew S, Miloslavski E, Kirsch M, Kühne for 3 days. Follow-up angiography performed 9 months D: Reconstructive treatment of dural arteriovenous fistulas of the transverse and sigmoid sinus: transvenous angioplasty after the procedure demonstrated normal cerebral venous and stent deployment. Neuroradiology 47:543–551, 2005 drainage without shunt flow and in-stent stenosis of the 14 8. Malek AM, Higashida RT, Balousek PA, Phatouros CC, transverse-sigmoid junction. Spiotta et al. described a Smith WS, Dowd CF, et al: Endovascular recanalization with patient with DAVF involving the superior sagittal sinus balloon angioplasty and stenting of an occluded occipital and torcular herophili who was treated with covered stent sinus for treatment of intracranial venous hypertension: tech- graft placement in the affected sinus. In that case, after nical case report. Neurosurgery 44:896–901, 1999 the procedure, the patient received aspirin and clopidogrel 9. Murphy KJ, Gailloud P, Venbrux A, Deramond H, Hanley D, daily, and heparin was intravenously administered. On Rigamonti D: Endovascular treatment of a grade IV transverse sinus dural arteriovenous fistula by sinus recanaliza- postoperative Day 4, however, the patient became acutely tion, angioplasty, and stent placement: technical case report. unresponsive, developed uncal herniation syndrome, and Neurosurgery 46:497–501, 2000 died because of in-stent superior sagittal sinus occlusion. 10. Newton TH, Cronqvist S: Involvement of dural arteries A study conducted by Levrier et al.6 demonstrated that in intracranial arteriovenous malformations. Radiology stent graft placement can induce the coagulation process 93:1071–1078, 1969 and may lead to cortical vein occlusion if appropriate an- 11. Nishijima M, Takaku A, Endo S, Kuwayama N, Koizumi F, ticoagulation therapy is not administered during the time Sato H, et al: Etiological evaluation of dural arteriovenous malformations of the lateral and sigmoid sinuses based on required for epithelialization of the stent by endothelial histopathological examinations. J Neurosurg 76:600–606, cells. Thus, those authors recommend the use of antiplate- 1992 let agents for 3 months after stent placement in the cerebral 12. Ohara N, Toyota S, Kobayashi M, Wakayama A: Superior venous sinus. In our case, after the procedure, the patient sagittal sinus dural arteriovenous fistulas treated by stent received 200 mg of cilostazol and 15 mg of rivaroxaban placement for an occluded sinus and transarterial emboliza- daily, and 3-month follow-up angiography demonstrated tion. A case report. Interv Neuroradiol 18:333–340, 2012 normal cerebral venous drainage without in-stent occlu- 13. Pan DH, Chung WY, Guo WY, Wu HM, Liu KD, Shiau CY, et al: Stereotactic radiosurgery for the treatment of dural ar- sion. Although the piling of several stents in the affected teriovenous fistulas involving the transverse-sigmoid sinus. J sinus of the DAVF was effective in the present case, we Neurosurg 96:823–829, 2002 believe that appropriate antithrombotic therapy, such as 14. Spiotta AM, Sivapatham T, Hussain MS, Hui FK, Moskowitz a combination therapy of antiplatelet and anticoagula- SI, Gupta R: Combined surgical and endovascular approach tion agents, is also important. However, the duration of to a complex dural arteriovenous fistula involving the supe- antithrombotic therapy is controversial. The patient will rior sagittal sinus and torcula. J Stroke Cerebrovasc Dis take 200 mg of cilostazol and 15 mg of rivaroxaban daily 21:283–288, 2012 15. Troffkin NA, Graham CB III, Berkmen T, Wakhloo AK: throughout his life. It is essential that follow-up cerebral Combined transvenous and transarterial embolization of a angiography or CT venography is performed. tentorial-incisural dural arteriovenous malformation followed by primary stent placement in the associated stenotic straight References sinus. Case report. J Neurosurg 99:579–583, 2003 1. Al-Shahi R, Bhattacharya JJ, Currie DG, Papanastassiou V, Ritchie V, Roberts RC, et al: Prospective, population-based Author Contributions detection of intracranial vascular malformations in adults: the Scottish Intracranial Vascular Malformation Study Conception and design: Takada. Drafting the article: Takada. (SIVMS). Stroke 34:1163–1169, 2003 Critically revising the article: Takada, Isaka. Administrative/tech- 2. Brown RD Jr, Wiebers DO, Torner JC, O’Fallon WM: Inci- nical/material support: Takada, Isaka, Nakakuki, Mitsuno. Study dence and prevalence of intracranial vascular malformations supervision: Kaneko. in Olmsted County, Minnesota, 1965 to 1992. Neurology 46:949–952, 1996 Correspondence 3. Choi BJ, Lee TH, Kim CW, Choi CH: Reconstructive treat- Shigeki Takada, Department of Neurosurgery, Hikone Municipal ment using a stent graft for a dural arteriovenous fistula of Hospital, 1882 Hassaka-cho, Hikone-shi, Shiga-ken 522-8539, the transverse sinus in the case of hypoplasia of the contra- Japan. email: [email protected].

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