88 |
6 Neuro-Ophthalmology in Dural Cavernous Sinus Fistulas (DCSFs) |
Table 6.1. Incidence of frequent signs and symptoms in DCSFs in recent series (Meyers et al. 2002; Stiebel-Kalish et al. 2002; de Keizer 2003; Theaudin et al. 2006; Suh et al. 2005)
|
Meyers et al. |
Stiebel-Kalish |
de Keizer |
Kim |
Theaudin |
Suh et al. |
|
(2002) |
et al. (2002) |
(2003) a |
(2006) |
et al. (2006) |
(2005) |
|
% of 135 |
% of 85 |
% of 68 |
% of 65 |
% of 27 |
58 |
Conjunctival injection |
93 |
76 |
66 |
|
41 |
* |
Chemosis |
87 |
21 |
- |
32 |
37 |
* |
Propotosis |
81 |
76 |
65 |
21 |
37 |
* |
Diplopia |
68 |
|
45 |
34 |
45 |
* |
Bruit |
49 |
28 b |
27 |
|
|
* |
Retroorbital pain |
34 |
|
11 |
34 |
|
* |
Elevated IOP |
34 |
72 |
|
|
|
* |
Decreased visual acuity |
31 |
|
26 |
13 |
30 |
* |
Retinal hemorrhage |
- |
18 |
18 |
|
|
* |
a De Keizer (2003) differentiated in 68 spontaneous (dural, orbital and direct) and 33 traumatic (direct and dural) fistulas
b Subjective bruit in 24 and objective in 7 patients |
|
|
* Suh et al. (2005): divided 58 patients into four main symptom pattern |
|
|
|
Orbital pattern (chemosis, exophthalmos,pain,eyelid swelling): |
53% |
|
Cavernous pattern (ptosis,diplopia, anisocoria, ophthalmoplegia): |
71% |
|
Ocular pattern (decreased vision, IOC > 20 mm Hg ocular pain, glaucoma, retinal hemorrhage): |
64% |
|
Cerebral pattern (seizures, hemorrhage): |
5% |
CS as a precondition for the presence of orbital symptoms in patients with DCSFs, although its angiographic appearance may be mimicked by an anatomical variant or be caused by a thrombotic occlusion of the IPS (Grove 1984; Hoops et al. 1997).
6.2.1 Exophthalmos
As a result of the chronically elevated intraorbital venous pressure a prolapse of the orbital soft tissue may develop, which is commonly less prominent than in patients with direct CCFs. In most cases it is less than 5 mm and can initially be overlooked. The most precise method of measurement is to examine the patient in reclining head position using the Hertel Exophthalmometer.
A massive exophthalmos, rarely observed in cases of DCSF, can lead to chemosis, lid swelling, lagophthalmos and corneal damage. If an acute increasing exophthalmos, associated with pain and lid swelling occurs and is followed by a spontaneous improvement, a thrombosis of the SOV or the CS should be considered.
6.2.2
Conjunctival Engorgement and Chemosis
Typically, arterialization of conjunctival veins is associated with other ophthalmologic manifestations, particularly with exophthalmos, and can be found in 82%–100% of patients (Phelps et al. 1982; Palestine et al. 1981; Kupersmith et al. 1988) with intraorbital symptoms. It may lead to dilatations and tortuosities of conjunctival veins, which are often the cause for misdiagnosis such as inflammatory conjunctivitis. However, the conjunctival injection in patients with CSF is, different from allergic, viral or bacterial conjunctivitis, characterized by brightred, corkscrew veins. Except for cases of secondary infections, it usually occurs without inflammatory secretion.
These veins are called specific epibulbar loops by De Keizer (2003) and represent the most superficial layer, developing due to opening of small capillary connections at the outside of the orbit (Fig. 6.3). Enlarged connections on the eyeball develop between the recurrent conjunctival ciliary veins and posterior conjunctival veins (specific limbal loops) (de Keizer 1979, 2003).