it or may not associate it with ocular symptoms (Miller 2007).

Comparable (audible) bruits in the craniofacial region can be found in patients with arteriosclerotic stenoses of the carotid siphon, subclavian artery or vascular tumors. A congenital or posttraumatic hypoor aplasia of the sphenoid bone may simulate the bruit of a CCF through transmission of brain pulsations to the orbit. A bruit may also be heard in rare cases of raised ICP or meningeomas (Miller 1998).

6.2.5

Pulse-synchronous Pulsation of the Eyelid and Bulb

Birch-Hirschfeld (1930) was the first to describe pulse-synchronous movements of the eye lid and bulb in patients with CCFs. They develop due to the arterializations of intraorbital veins, also involve the bulb, and are visible or can be found by palpation in about 5% – 20% of patients with DCSF. Bilateral assessment of ocular pulse amplitudes (OPA) using the pneumotonometer or Goldmann tonometer differs in 93% of patients with CCF by >1.6 mm, and is a reliable non-invasive method for identifying a CCF (Golnik and Kulwin 1997; Golnik and

Miller 1992).

6.2.6

Secondary Glaucoma and Visual Loss

After manifestation of orbital symptoms, the chronic elevated intraorbital venous pressure may lead in 20% of patients with DCSF to a blockage of Schlemm’s canal. This may subsequently lead to gonioscopically detectable elevated intraocular pressure (secondary glaucoma), retinal ischemia and usually reversible loss of visual acuity. Many authors postulate that the elevated episcleral venous pressure is responsible for secondary glaucoma, rarely for papilla edema, retinal ablations, central vein thrombosis and hemorrhagic retinopathy (2%) (Phelps et al. 1982; Barke et al. 1991; Jorgensen and Gutthoff 1985). In 11% of the patients bilateral symptoms are found. In general, the clinical severity of visual loss correlates more with the venous drainage pattern than with the volume and flow velocity of AV shunt. Meyers et al. (2002) found diminished visual acuity is found in up to 31%.

In patients with rapid visual loss, neuropathy of the optic nerve and occlusion of the superior ophthalmic vein are found, respectively, while distal stenosis merely contributes to clinical improvement (Halbach et al. 1992). Patients with a DCSF and fulminant glaucomatous loss of vision need, beside endovascular therapy, temporary local β-blocker or Diamox (Acetazolamide) application, or even more invasive ophthalmologic intervention (canthotomy, gonioplasty) (Fiore et al. 1990). It cannot be emphasized enough that in patients with unilateral glaucoma, a DCSF must always be included in the differential diagnosis.

Stiebel-Kalish et al. (2002) have provided the most detailed description of frequency of signs and symptoms in a larger group (85) of patients so far. The authors differentiated cranial neuropathy accordingly into sixth (34%), third (19%), fourth (5%) nerve palsies, fifth nerve dysfunction (2%) and facial nerve paresis (1%). They found relatively frequent optic neuropathy (31%), vertigo in 5%, intracerebral hemorrhage in 2%, and cortical venous infarct in 1% of their patients.

6.3

Other and Neurological Symptoms

Intracranial hemorrhage caused by CSFs has already been reported to occur by Sattler (1930), De Schweinitz and Holloway (1908) and others in about 3% of cases, most of which, however being caused by CSFs of traumatic origin. Harding et al. (1984) reported on two patients with a DCSF, who experienced a spontaneous intracerebral hemorrhage within 18 months after onset of their symptoms. Sakuma et al. (2006) reported recently a case where the hemorrhage developed contralateral to the fistula side, mimicking a hypertensive putaminal bleeding. Kuwayama et al. (1998) described a patient who presented with frontal subcortical hemorrhage and Nakahara et al. (1996) reported another who developed a temporo-parietal hematoma due to a ipsilateral fistula. Although cortical or leptomeningeal drainage can be found in 31% of the patients, intracerebral hemorrhage seem to occur less frequently than in DAVF, in only 1.5% (Meyers et al. 2002). In general, central nervous system symptoms or dysfunction are less frequent and have been observed in larger patient groups in only 7/85 cases with vertigo

(5%), intracerebral hemorrhage (2%) and cortical venous infarct (1%) (Stiebel et al. 2002).

Cerebral or cerebellar symptoms can be caused by a venous outflow restriction or venous hypertension. They are rare events and occur less frequently than in DAVFs and are only observed, if a cortical venous drainage is present. Iwasaki et al. (2006) have recently reported a DCSF complicated by pontine venous congestion. The authors observed isolated sixth nerve palsy in a 71-year-old woman that was caused by brain stem edema due to an AV shunt with exclusive venous posterior drainage into SPS, cerebellar cortical veins and inferior vermian vein. Only a few more of such cases have been reported so far (Uchino et al. 1997; Kurata et al. 1999; Kai et al. 2004; Takahashi et al. 1999), showing that in fact a “cortical” venous drainage is not always the cause, but often a leptomeningeal retrograde venous drainage of the AV shunt instead (Davies et al. 1997).

An unusual clinical presentation is posterior ischemic optic neuropathy (PION) as recently suggested by Hashimoto et al. (2005), who observed a patient with sudden unilateral vision loss after an ocular motor disturbance and pulsatile tinnitus. The arteriogram revealed a fistula which was in part supplied by a recurrent meningeal branch arising from the ophthalmic artery possibly causing arterial steal.

Other rare complications of DCSF include macular exudative retinal detachment (Garg et al. 2006), abnormal choroidal circulation (Klein et al. 1978), myelopathy (Ohnishi et al. 2003), and facial nerve paresis (Moster et al. 1988).

6.4

Di erential Diagnosis

Dural CSFs presenting with mild and slowly progressing symptoms are often misdiagnosed in their early stage (Miller 2007). Considering a DCSF in the differential diagnoses of inflammatory and other orbital diseases can be crucial. In a recent study, Stiebel-Kalish et al. (2002) were able to demonstrate a good correlation between venous drainage pattern and clinical signs. Drainage into the anterior CS and SOV was well correlated with orbital congestion, elevated IOP and optic neuropathy. Drainage into the IPS was well correlated with third nerve

palsy, drainage into the SPS allowed prediction for CNS symptoms. In series only 10 patients with bilateral signs had true bilateral AV shunts. While four patients had bilateral eye signs without evidence of drainage into the SOVs, three had unilateral congestion with bilateral shunts draining into both SOV.

Ikeda et al. (2005) reported recently on a patient with prominent anterior drainage who presented with absent orbito-ocular signs. By contrast, cases with dominant posterior drainage may present not with the typical “white-eyed cavernous shunt” as described by Acierno et al. (1995). I have seen patients that, despite exclusive posterior drainage, presented with eye-redness (Fig. 6.3). The angiographic demonstration of either anterior or posterior drainage alone will not always or not completely explain the symptoms (Fig. 6.6). Equally or even more important is probably the associated venous pressure. This pressure may, especially in low-flow fistulas, not be significantly elevated and only increases if venous outflow restriction starts to occur.

Various pathologies should be considered differential diagnoses in clinical practice, including conjunctivitis, thyroid orbitopathy, orbital pseudotumor, myositis, orbital cellulites, episcleritis, meningeoma or Tolosa-Hunt syndrome and allergic reactions. (Brazis 1994; Grove 1984; Miller 2007; Newton 1970; Oestreicher 1995; Phelps 1982; Procope 1994). Pulsating exophthalmos can also be caused by sphenoid dysplasia in neurofibromatosis (Recklinghausen) or after neurosurgical removal of the orbital roof. Dilated episcleral and conjunctival loops can be observed in CS thrombosis, venous malformations, brain AVMs or DAVFs (see Figs. 7.48, 7.49). Other causes include Graves’ disease (Lore et al. 2003), idiopathic elevated episcleral pressure, orbital vein variation, superior vena cava syndrome, pulmonary hypertension (Akduman et al. 1996), scleritis with vortex vein blockage and malignant endocrine exophthalmos (de Keizer 2003). If the fistula is small and thus not detectable by CT or MRI, a patient can be misdiagnosed, leading not only to distress but also to inadequate therapeutic measures and false treatment effects (Figs. 6.4 and 6.7). Theaudin et al. (2006) reported just recently a delay in diagnosis of up to 22 months; similar to my own experience (Fig. 6.5., Case Report I), underlining the diagnostic dilemma in patients with small AV-shunts, not detectable by CT or MRI. Selective catheter angiography is indispensable in these cases and can be performed by an experienced neuroradiologist with very low morbidity (Willinsky et al. 2003).

In summary, the signs and symptoms in patients with low-flow DCSF are in principle similar to those with direct high-flow CCF, but milder and less progressive. In the initial stage of the disease, nonspecific signs such as retro orbital headaches, mild conjunctival injection or isolated diplopia may occur. Consequently, the disease may be overlooked and can be mistaken as endocrine orbitopathy, conjunctivitis or ocular myositis. Neglecting a DCSF in the clinical differential diagnoses may cause progression of the disease with serious deterioration of the patient’s symptoms including the risk of complete vision loss.

References

Acierno MD, Trobe JD, Cornblath WT, Gebarski SS (1995) Painful oculomotor palsy caused by posterior-drain- ing dural carotid cavernous fistulas. Arch Ophthalmol 113:1045–1049

Akduman L, Del Priore LV, Kaplan HJ, Meredith T (1996) Uveal effusion syndrome associated with primary pulmonary hypertension and vomiting. Am J Ophthalmol 121:578–580

Barke RM, Yoshizumi MO, Hepler RS, Krauss HR, Jabour BA (1991) Spontaneous dural carotid-cavernous fistula with central retinal vein occlusion and iris neovascularization. Ann Ophthalmol 23:11–17

Benndorf, G, et al. (1999) Occlusion of the inferior petrosal sinus (IPS) for endovascular treatment of a longstanding traumatic carotid cavernous sinus fistula (CCF). In Annual Meeting, European Society of Neuroradiology. Vienna.

Birch-Hirschfeld A (1930) Kurzes Handbuch der Ophthalmologie, vol 1. Springer, Berlin Heidelberg New York Brazis PW, et al. (1994) Low flow dural arteriovenous shunt:

another cause of „sinister“ Tolosa-Hunt syndrome. Headache 34:523–525

Davies M, Saleh J, Ter Brugge K, Willinsky R, Wallace MC (1997) The natural history and management of intracranial dural arteriovenous fistulae. Intervent Neuroradiol 3 de Keizer RJ (1979) Spontaneous carotico-cavernous fistulas. The importance of the typical limbal vascular loops for the diagnosis, the recognition of glaucoma and the uses of conservative therapy in this condition. Doc Ophthalmol

46:403–412

de Keizer R (2003) Carotid-cavernous and orbital arteriovenous fistulas: ocular features, diagnostic and hemody-

namic considerations in relation to visual impairment and morbidity. Orbit 22:121–142

De Schweinitz G, Holloway T (1908) Pulsating exophthalmos: its etiology, symptomatology, pathogenesis and treatment. Saunders, Philadelphia

Eggenberger, E, et al. (200) A bruital headache and double vision. Surv Ophthalmol. 45(2):147–153.

Fiore PM, Latina MA, Shingleton BJ, Rizzo JF, Ebert E, Bellows AR (1990) The dural shunt syndrome. I. Management of glaucoma [see comments]. Ophthalmology 97:56–62

Garg SJ, Regillo CD, Aggarwal S, Bilyk JR, Savino PJ (2006) Macular exudative retinal detachment in a patient with a dural cavernous sinus fistula. Arch Ophthalmol 124:1201–1202

Golnik C, Kulwin D (1997) CCF: neuro-ophthalmolgic findings. In: Tomsick TA (ed) Carotid cavernous fistula. Digital Educational Publishing, Philadelphia, pp 75–82

Golnik KC, Miller NR (1992) Diagnosis of cavernous sinus arteriovenous fistula by measurement of ocular pulse amplitude [see comments]. Ophthalmology 99:1146–1152

Grove AS Jr (1984) The dural shunt syndrome. Pathophysiology and clinical course. Ophthalmology 91:31–44

Halbach VV, Higashida RT, Hieshima GB, Reicher M, Norman D, Newton TH (1987) Dural fistulas involving the cavernous sinus: results of treatment in 30 patients. Radiology 163:437–442

Halbach VV, Hiogashida RT, Hieshima GB, Dowd CF (1992) Endovascular therapy of dural fistulas. In: Vinuela F, Halbach VV, Dion J (eds) Interventional neuroradiology. Raven Press, New York, p 32

Harding AE, Kendall B, Leonard TJ, Johnson MH (1984) Intracerebral haemorrhage complicating dural arteriovenous fistula: a report of two cases. J Neurol Neurosurg Psychiatry 47:905–911

Hashimoto M, Ohtsuka K, Suzuki Y, Hoyt WF (2005) A case of posterior ischemic optic neuropathy in a posteriordraining dural cavernous sinus fistula. J Neuroophthalmol 25:176–179

Hawke SH, Mullie MA, Hoyt WF, Hallinan JM, Halmagyi GM (1989) Painful oculomotor nerve palsy due to duralcavernous sinus shunt. Arch Neurol 46:1252–1255

Hoops JP, Rudolph G, Schriever S, Nasemann JE, Bien S, Kuffer G, Schworm HD, Kampik A (1997) Dural carotidcavernous sinus fistulas: clinical aspects, diagnosis and therapeutic intervention. Klin Monatsbl Augenheilkd 210:392–397

Ikeda K, Deguchi K, Tsukaguchi M, Sasaki I, Shimamura M, Urai Y, Touge T, Kawanishi M, Takeuchi H, Kuriyama S (2005) Absence of orbito-ocular signs in dural carotidcavernous sinus fistula with a prominent anterior venous drainage. J Neurol Sci 236:81–84

Iwasaki M, Murakami K, Tomita T, Numagami Y, Nishijima M (2006) Cavernous sinus dural arteriovenous fistula complicated by pontine venous congestion. A case report. Surg Neurol 65:516–518; discussion 519

Jorgensen JS, Gutthoff RF (1985) 24 cases of carotid cavernosus fistulas: frequency, symptoms, diagnosis and treatment. Acta Ophthalmol Suppl 173:67–71

Kai Y, Hamada JI, Morioka M, Yano S, Ushio Y (2004) Brain stem venous congestion due to dural arteriovenous fistulas of the cavernous sinus. Acta Neurochir (Wien) 146:1107–1111; discussion 1111–1102

Keltner JL, Gittinger JW Jr, Miller NR, Burder RM (1987a)

A red eye and high intraocular pressure [clinical conference]. Surv Ophthalmol 31:328–336

Keltner JL, Satterfield D, Dublin AB, Lee BC (1987b) Dural and carotid cavernous sinus fistulas. Diagnosis, management, and complications. Ophthalmology 94:1585–1600

Kim, DJ, et al. (2006) Results of transvenous embolization of cavernous dural arteriovenous fistula: a single-center experience with emphasis on complications and management. AJNR Am J Neuroradiol. 27(10):2078–2082.

Klein R, Meyers SM, Smith JL, Myers FL, Roth H, Becker B (1978) Abnormal chloroidal circulation: association with arteriovenous fistula in the cavernous sinus area. Arch Ophthalmol 96:1370–1373

Komorsky GB (1988) Carotid cavernous sinus fistulas presenting as painful ophthalmoplegia without external ocular signs. J Clin Neuro Ophthalmol 8:131–135

Kupersmith MJ, Berenstein A, Flamm E, Ransohoff J (1986) Neuroophthalmologic abnormalities and intravascular therapy of traumatic carotid cavernous fistulas. Ophthalmology 93:906–912

Kupersmith MJ, et al. (1988) Management of nontraumatic vascular shunts involving the cavernous sinus. Ophthalmology 95:121–130

Kupersmith MJ, Vargas EM, Warren F, Berenstein A (1996) Venous obstruction as the cause of retinal/choroidal dysfunction associated with arteriovenous shunts in the cavernous sinus. J Neuroophthalmol 16:1–6

Kurata A, Miyasaka Y, Oka H, Irikura K, Tanaka R, Ohmomo T, Nagai S, Fujii K (1999) Spontaneous carotid cavernous fistulas with special reference to the influence of estradiol decrease. Neurol Res 21:631–639

Kuwayama N, Endo S, Kitabayashi M, Nishijima M, Takaku A (1998) Surgical transvenous embolization of a cortically draining carotid cavernous fistula via a vein of the sylvian fissure. AJNR Am J Neuroradiol 19:1329–1332

Lore F, Polito E, Cerase A, Bracco S, Loffredo A, Pichierri P, Talidis F (2003) Carotid cavernous fistula in a patient with Graves‘ ophthalmopathy. J Clin Endocrinol Metab 88:3487–3490

Madsen PH (1970) Carotid-cavernous fistulae. A study of 18 cases. Acta Ophthalmol (Copenh) 48:731–751

Meyers PM, Halbach VV, Dowd CF, Lempert TE, Malek AM, Phatouros CC, Lefler JE, Higashida RT (2002) Dural carotid cavernous fistula: definitive endovascular management and long-term follow-up. Am J Ophthalmol 134:85–92

Miller N (1998) Carotid-cavernous sinus fistulas. In: Miller N, Newmann N (eds) Walsh and Hoyt‘s clinical neuroophthalmology. Williams and Wilkins, Baltimore, pp 1524–1526

Miller, NR (2007) Diagnosis and management of dural ca- rotid-cavernous sinus fistulas. Neurosurg Focus. 23(5): p. E13

Miyachi S, Negoro M, Handa T, Sugita K (1993) Dural carotid cavernous sinus fistula presenting as isolated oculomotor nerve palsy. Surg Neurol 39:105–109

Moster ML, Sergott RC, Grossman RI (1988) Dural carotidcavernous sinus vascular malformation with facial nerve paresis. Can J Ophthalmol 23:27–29

Nakahara I, Taki W, Murao K, Ohkata N, Matsumoto K, Isaka F, Kikuchi H (1996) Endovascular treatment of cavernous dural AVFs (spontaneous CCFs): results in 50

patients. In: Taki W, Picard L, Kikuchi H (eds) Advances in interventional neuroradiology. Elsevier Science, Amsterdam, pp 251–256

Newton TH, Hoyt WF (1970) Dural arteriovenous shunts in the region of the cavernous sinus. Neuroradiology, 1970. 1:71–81

Oestreicher, JH, Frueh BR (1995) Carotid-cavernous fistula mimicking Graves’ eye disease. Ophthal Plast Reconstr Surg,. 11(4):238–244

Ohnishi H, Deguchi J, Yamada M, Kuroiwa T (2003) Cavernous arteriovenous fistula presenting myelopathy: a case report. No Shinkei Geka 31:1119–1123

Ott D, Bien S, Krasznai L (1993) Embolization of a tentorial dural arterio-venous fistula presenting as atypical trigeminal neuralgia. Headache 33:503–508

Palestine AG, Younge BR, Piepgras DG (1981) Visual prognosis in carotid-cavernous fistula. Arch Ophthalmol 99:1600–1603

Phelps CD, Thompson HS, Ossoinig KC (1982) The diagnosis and prognosis of atypical carotid-cavernous fistula (redeyed shunt syndrome). Am J Ophthalmol 93:423–436

Procope, JA, et al. (1994) Dural cavernous sinus fistula: an unusual presentation. J Natl Med Assoc, 1994. 86(5):363–364.

Rizzo M, Bosch EP, Gross CE (1982) Trigeminal sensory neuropathy due to dural external carotid cavernous sinus fistula. Neurology 32:89–91

Sakuma I, Takahashi S, Tomura N, Kinouchi H (2006) Dural arteriovenous fistulas of the cavernous sinus with onset of intracerebral haemorrhage mimicking hypertensive putaminal hemorrhage. Acta Neurochir (Wien) 148:915–918

Sattler H (1930) Pulsierender Exophthalmus. In: Graefe A, Saemisch T (eds) Handbuch der Gesamten Augenheilkunde. Springer, Berlin Heidelberg New York, pp 745–948

Stiebel-Kalish H, Setton A, Nimii Y, Kalish Y, Hartman J, Huna Bar-On R, Berenstein A, Kupersmith MJ (2002) Cavernous sinus dural arteriovenous malformations: patterns of venous drainage are related to clinical signs and symptoms. Ophthalmology 109:1685–1691

Suh DC, et al. (2005) New concept in cavernous sinus dural arteriovenous fistula: correlation with presenting symptom and venous drainage patterns. Stroke 36:1134–1139

Takahashi S, Tomura N, Watarai J, Mizoi K, Manabe H (1999) Dural arteriovenous fistula of the cavernous sinus with venous congestion of the brain stem: report of two cases. AJNR Am J Neuroradiol 20:886–888

Theaudin M, Saint-Maurice JP, Chapot R, Vahedi K, Mazighi M, Vignal C, Saliou G, Stapf C, Bousser MG, Houdart E (2006) Diagnosis and treatment of dural carotid-cavern- ous fistulae: a consecutive series of 27 patients. J Neurol Neurosurg Psychiatry

Uchino A, Kato A, Kuroda Y, Shimokawa S, Kudo S (1997) Pontine venous congestion caused by dural carotid-cav- ernous fistula: report of two cases. Eur Radiol 7:405– 408

Vinuela F, Fox AJ, Debrun GM, Peerless SJ, Drake CG (1984) Spontaneous carotid-cavernous fistulas: clinical, radiological, and therapeutic considerations. Experience with 20 cases. J Neurosurg 60:976–984

Voigt K, Sauer M, Dichgans J (1971) Spontaneous occlusion of a bilateral caroticocavernous fistula studied by serial angiography. Neuroradiology 2:207–211