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What is the diagnosis and what is the treatment?

¿Cuál es su diagnóstico y tratamiento?

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A 67-year-old patient reported a one-month history of shooting headaches with Valsalva maneuvers, ocular pain and redness on the right side and intermittent diplopia. Over the previous ten days progressive exophthalmos of the right eye and a persistent type of diplopia had developed. His personal history was not of relevance to the case.

The ophthalmologic examination revealed an intraocular pressure of 24 mm mercury (normal IOP is 12 to 22 mm mercury), diplopia on upgaze and venous dilation in the temple and nasal [regions], with a certain blurring on the nasal of the papilla.

An emergency CT scan was requested, and an intraorbital extraconal tumor was observed at a supero-external angle of the right orbit, with a diameter of 1 cm, that was displacing the ocular globe medially and downwards. The intrinsic musculature and bony structures appeared normal. He was admitted for further tests. Antibiotics and corticoid treatment was given together with ocular treatment consisting of epithelium ointment (Fig. 1).

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Carotid-cavernous fistula

Fístula carótido-cavernosa

 

A. Riaño Argüelles¹, M.A. Bada García², C. Sebastián López¹, J. Garatea Crelgo²

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1 Médico Residente.
2 Cirujano Adjunto.
Servicio de Cirugía Oral y Maxilofacial
Hospital Virgen del Camino. Pamplona, España

Correspondencia:
Ana Riaño Argüelles
Plaza Rafael Alberti nº9 1ºC
31010 Barañain. Navarra, España

 

During his hospital stay an echography of the orbit was carried out, in which the abnormal size of the superior ophthalmic vein could be appreciated. It had a lowflow and a carotid-cavernous fistula was suspected (Fig. 2).

The Department of Radiology recommended further study with a CT scan of the cavernous sinuses with i.v. contrast. This confirmed the engorgement of the ophthalmic vein, as well as an enlargement of the right cavernous sinus.

A diagnostic angiography was carried out using the Seldinger technique that revealed a low-flow cavernous-carotid fistula, with shunting from both sides. It was supplied mainly by the ascending pharyngeal artery and drainage was via the right ophthalmic vein (Fig. 3).

The case was discussed with the Neurosurgery Department and, given the various symptoms, conservative treatment was decided on, with the patient himself massaging the right carotid for three minutes three times during the morning and three times in the afternoon with an outpatient follow-up.

A month later the exophthalmos and the diplopia had receded and an angioresonance check of the brain was carried out. The fistula had disappeared and an ophthalmic vein with a normal diameter was observed. The patient was discharged.

Carotid-cavernous fistulas are anomalous communications that arise between the carotid artery and the cavernous sinus, either directly or through the intradural branches of the internal or external carotid arteries. They can be spontaneous (congenital, degenerative, infectious) or traumatic (three quarters).⁸

Barrow et al.³ classified them according to angiographic findings into two groups: Direct or type A carotid-cavernous fistulas, and the indirect or dural (type B-C-D). The "direct" fistulas are produced as a result of a rupture of the internal carotid artery within the cavernous sinus. There is a high-flow, and the clinical onset is dramatic. They often occur following trauma or because of the rupture of an aneurysm. Cases have been described following a Le Fort I type osteotomy. ²

Those with a low-flow, or that are "indirect", are produced through a generally spontaneous rupture of the smaller branches the internal or external carotid arteries and the cavernous sinus. They are clinically indolent, and they appear more frequently in perimenopausal women. They are attributed to a multiple of causes among which are congenital anomalies, spontaneous venous hypertension due to thrombosis, arteriosclerosis, collagen diseases, syphilitic arteritis and iatrogenic vascular injury.

These are divided into: type B (meningeal branches of the internal carotid artery), type C (meningeal branches of the external carotid artery) and type D (branches of both arteries).

The new fistulous connection produces, in addition to the typical compressive symptoms of an "intraorbital mass", increased flow together and intracavernous pressure, together with a retrograde flow. This reverse flow leads to orbital venous hypertension and, as a result pulsating exophthalmos, chemosis, retinal venous congestion, headaches and orbital pain. A pathological sign is fronto-orbital whistling (tinnitus) in time with the pulse on lying down. There is an early onset of ptosis and diplopia, with the latter being the most common symptom, as the occulomotor muscles are compressed. How serious this is depends on the amount of fluid and the capacity for venous drainage.

The pattern of venous drainage frequently dictates the clinical findings and radiographic appearance. Although anterior drainage into the sinus and ophthalmic veins produces the most ocular symptomatology and a greater lengthening of the superior orbital vein, it takes longer to detect using CT and MR.

An echography is crucial for pin-pointing this pathology as the cause of this group of symptoms and not any other within the "orbital masses" group. An arterialized flow, reversed into the superior ophthalmic vein can be observed.

Radiographic findings of the fistula will show an increase in the size of the superior orbital vein (that is not specific to the fistula), lateral bulging of the cavernous sinus, enlargement of the extraocular muscles, and an abnormal flow in the cavernous sinus.

Performing gadolinium magnetic resonance angiography is of fundamental importance if there is no anterior drainage nor an enlargement of the superior ophthalmic vein. If there is a fistula, a hyperintense image will be observed in the sinus, which would correspond to a carotid-cavernous fistula with a sensitivity of 83% and specificity of 100%.1 However, this technique is not able to distinguish between the arteries implied in neither the fistula nor the cortical venous drainage, and for this a normal angiography would be necessary.

The differential diagnosis should be made using various procedures capable of producing the displacement of the globe: benign tumors (hemangiomas, dermoid and epidermoid cysts, frontoethmoidal mucoceles, lacrimal gland tumors), malignant (tumors of the lacrimal gland; leukemias and lymphomas; metastasis principally of the breast, lungs, malignant melanoma, gastric carcinoma, genitourinary carcinoma; rhabdomyosarcoma, glioma of the optic nerve or juvenile pilocytic astrocytoma), thyroid ophthalmopathy, infections (orbital cellulitis, pansinusitis), retrobulbar hemorrhages secondary to trauma, orbital vasculitis (Wegener's granulomatosis, PAN), sarcoidosis, etc.

The first successful treatment with this group of symptoms was carried out by the British surgeon Travers, and it consisted in ligating the common carotid artery, and since then therapeutic advances have been plentiful. When there is intracranial hypertension, neurologic deficits, loss of vision, transitory ischemic attacks etc treatment should be given urgently.^6,7 The therapeutic approach varies depending on the type of fistula we are dealing with.

A "direct fistula" or one with a high-flow: embolization of the artery by means of an endovascular balloon or particles.

An "indirect" fistula: The previous treatment is not possible because a multiple of tiny arterial feeders are received from the internal or external carotid arteries. If the symptoms are stable, there is an inclination towards observation. 30% of cases are solved by means of manual compression at regular intervals, as in the case we are dealing with. Nevertheless, this should be supervised closely, because there can be a rapid deterioration in vision or in the function of the cranial nerves, as a consequence of an increase in intraocular pressure caused by retrograde venous flow through the superior ophthalmic vein. For the external carotid veins (type C) the approach is through the cavernous sinus, and the branches of the external carotid artery are embolized with polyvinyl alcohol and an endovascular balloon is placed distally at the point of entry, so that there is selective vascular damage, with no migration of the alcohol along the vessel. This type of approach would be impossible to carry out if there was angiographic evidence of an inferior petrosal sinus or if the superior ophthalmologic vein had a sharp bend, because of the high risk of iatrogenic perforation and retroorbital hemorrhaging. With this technique a rapid improvement is achieved in vision acuity, extraocular mobility and there is a significant descent in intraocular pressure.

In the D types only the branches of the external carotid are embolized, given the difficulty of cauterizing the very fine branches of the internal carotid, for fear of introducing the sclerosing agents in the interior of the cavernous sinus.

Finally, in those patients in whom residual fluid has been observed and with symptoms that have not been completely resolved, stereotactic radiosurgery should be considered.

References

1. Rucker JC, Biousse V, Newmann NJ. Magnetic resonance angiography source images in carotid cabernous fistulas. Br J Ophthalmol 2004;88:311.        [ Links ]

2. Precious David S. Management of complications of maxillary osteotomies. J Oral Maxillofac Surg Online Septiembre, 2004.        [ Links ]

3. Koebbe CJ, Horowitz M, Jungreis C. Alcohol embolization of carotid-cavernous indirect fistulae. Neurosurgery Online 2003;52:1111.        [ Links ]

4. Rhee DJ, Pyfer MF. Manual de Urgencias Oftalmológicas. 3ª ed. McGraw-Hill Interamericana Nov 2000, p.p. 181-205.        [ Links ]

5. Villacampa T. Oftalmología. Curso MIR ASTURIAS 2002, p.p. 111-118.        [ Links ]

6. Chaloupka JC, Putman CM. Endovascular therapy for surgical diseases of the cranial base. Clin Plast Surg 1985;77:981.        [ Links ]

7. Halbach W, Hieshima GB, Higashida RT, y cols. Carotid-cavernous fistula: indications for urgent treatment. AJNR 1987;8:627-33.        [ Links ]

8. Albertos JM, Junquera LM, Diego J, Villarreal P. Fístula carótido-cavernosa asociada a una fractura mandibular. Rev Esp Cir Oral Maxilofac 1997;19:145-50.        [ Links ]