C O N T E N T S

6.1.1Orbital Pain 86

6.1.2Cranial Nerve Deficits and Ophthalmoplegia 87

6.2Orbital Symptoms 87

6.2.1Exophthalmos 88

6.2.2Conjunctival Engorgement and

Chemosis 88

6.2.2.1 Retinal Hemorrhage 89

6.2.3Corneal Damage 89

6.2.4Orbital Bruit 90

6.2.5Puls-synchronous Pulsation of

6.4Differential Diagnosis 92

References 94

Introduction

Hemodynamic dysregulation in AV-shunting lesions of the CS lead in 80% of cases to elevated pressure in periand intraorbital veins. This results in interstitial edema and increased caliber of the orbital veins and the CS, which causes in turn mechanical compression and ischemia. Spectrum and progression of resulting neuroophthalmological deficits in patients with a DCSF are determined by individual hemodynamics and angioarchitecture of the fistulas drainage (Table 6.1).

Most DCSFs drain via the superior ophthalmic vein into the angular, supraorbital and facial veins. Such anterior drainage is usually associated with more impressive clinical symptoms. It may cause ipsilateral CN deficits and damage to orbital organs. The posterior drainage via IPS or SPS instead rarely causes ophthalmologic symptoms, but may be re-

sponsible for oculomotor deficits due to ischemic, or less frequently, mechanical disturbance of CN functions. Fistulas with posterior drainage may also cause trigeminal neuropathy or facial nerve paresis (Eggenberger 2000; Rizzo 1982).

Association with local thrombosis of the CS or IPS is often found. It may lead to a rapid deterioration caused by acute elevation of the intravenous and intraocular pressures and can be the reason for slow recovery later on. Bior contralateral symptoms occur in 10% of the patients with DCSFs and can be due to thrombotic occlusions of ipsilateral draining veins and involvement of intracavernous and /or basilar sinuses as well as of the contralateral CS in the fistulas drainage. It remains unclear whether venous thrombosis, often seen on angiograms, has developed secondarily on the basis of hemodynamic turbulences, or as a residuum of the initial thrombotic processes considered a triggering factor in the pathogenesis of DCSFs (Grove 1984). Complications and unfavorable long-term outcomes in the natural course of the disease mainly involve the eye. The spontaneous occlusion rate of DCSFs in the literature may lie between 11% and 90%, depending on observations made by different authors (Vinuela et al. 1984, Keltner et al., 1987b, Kupersmith 1988). Interestingly enough, several authors have reported disappearance of the AV shunting following diagnostic angiography (Grove 1984; Keltner et al. 1987b; Phelps et al. 1982; Voigt et al. 1971). Thus, spontaneous cure seems possible and should be considered in therapeutic decision-making.

The classical Dandy’s triad seen in Type A or traumatic CCFs (Fig. 6.1) – chemosis, exophthalmos and bruit – is rarely observed in patients with dural CSF. Because of the usually chronic, clinically milder and variform manifestation of symptoms, the diagnosis of a DCSF can be less straightforward and may not allow a standard procedural regimen.

If an individual patient presents with nonspecific symptoms, the clinical picture may provide initial