Treatment of low flow, indirect cavernous sinus dural arteriovenous fistulas with external manual carotid compression - the UK experience

Retinal arterial-venous pulse delay: a new specific marker for a carotid-cavernous fistula

Purpose

The purpose of the study was to describe ocular blood flow changes in eyes affected by a carotid-cavernous fistula (CCF) using laser speckle flowgraphy. We hypothesized that imaging blood flow velocity waveforms in the retinal arterioles and venules simultaneously would reveal specific characteristics of an arteriovenous (AV) connection.

Design

The study was an observational case series, with a retrospective case-control analysis.

Methods

Five patients with a CCF underwent measurement of ocular blood flow using laser speckle flowgraphy. The blood flow was compared retrospectively between a control group of healthy subjects (n = 32) and patients with an elevated intraocular pressure or venous outflow impairment without an AV fistula (n = 40). The outcomes were derived from the arteriole and venule blood flow velocity waveforms, including an A-V phase delay and flow pulsatility.

Results

The presence of an active CCF was associated with an increased delay in the peak velocity measured in the retinal venule (10.7% ± 2.2% of the cardiac cycle duration) compared with unaffected fellow eyes (1.8% ± 0.2%; p = 0.05) or control eyes of normal subjects (2.7% ± 0.3%; p = 0.02). This delay disappeared after fistula thrombosis and was not present in eyes with a central retinal vein occlusion (CRVO), glaucoma, non-arteritic anterior ischemic optic neuropathy (NAION), or papilledema. The venule blood flow velocity decreased during systole (and in some cases momentarily stopped), leading to a delayed pulse with a greater amplitude in the venules than in fellow eyes and normal controls after normalizing to the arteriole amplitude (1.71 ± 0.3 vs 0.54 ± 0.03 vs 0.59 ± 0.02; p = 8.0E-12). This specific AV delay could also be identified in a scanning laser ophthalmoscope (SLO; SPECTRALIS®) video.

Conclusion

Laser speckle flowgraphy reveals dynamic retinal vascular changes in eyes affected by a CCF, which are not present in healthy controls or patients with other eye conditions, and which reverses with treatment.

Intermittent Manual Carotid Compression as a Treatment Option for Indirect Low Flow Carotid Cavernous Fistula

PURPOSE

To evaluate the efficacy of intermittent manual carotid compression (IMCC) in the management of low-flow carotid cavernous fistulae (CCF).

MATERIALS AND METHODS

Patients diagnosed with low-flow CCF and treated with IMCC over a period of 13 years were retrospectively analyzed. Data analyzed included demographic details, clinical features, type of CCF, and response to therapy. Outcomes were categorized as complete cure, partial cure, and no cure or worsening. Patients with complete and partial cure were grouped as good outcome whereas those with no cure or worsening as poor outcome.

RESULTS

A total of 44 patients were advised IMCC for low-flow CCF, of whom five were lost to follow-up. Results of the remaining 39 patients were analyzed, of whom 21 (53.8%) were males. The mean age at presentation was 54.38 ± 14.54 years. The median duration between the onset of symptoms and presentation was 5.0 ± 4.10 months. The common presenting features were episcleral congestion and proptosis (89.7%), extraocular motility restriction (66.7%), and diplopia (48.7%). Most common CCF type was type D (34, 87.2%). All patients were advised to undergo IMCC. Good outcome was seen in 35 patients (89.7%, 95% CI: 80.2% to 99.2%), whereas poor outcome was seen in four (10.3%) patients. The mean duration of follow-up was 15.91 ± 21.87 months.

CONCLUSION

The present study found a good outcome with IMCC in 89.7% cases of indirect low-flow CCF with no major complications. It should be considered the management of choice in patients who are systemically unfit or cannot afford endovascular embolization.

Bilateral cavernous sinus dural arteriovenous fistula with initial ocular symptom: A case report

RATIONALE

Cavernous sinus dural arteriovenous fistula (CSDAVF) is a rare intracranial vascular malformation. Because of its complicated clinical manifestations, it is easy to miss or misdiagnose CSDAVF.

PATIENT CONCERNS

A 42-year-old female had chief complaint that the right eyeball had conjunctival congestion for half a year. She was given levofloxacin eye drops to treat the right eye with anti-inflammatory treatment, but the symptoms did not improve. Cranial magnetic resonance and cerebrovascular imaging showed that the right lateral rectus muscle was slightly enlarged, the right eyeball was prominent, but there was no abnormality in the brain.

DIAGNOSES

Based on clinical and imaging examinations and digital subtraction angiography (DSA), she was diagnosed as low-flow CSDAVF.

INTERVENTIONS

The patient received interventional embolization with transvenous combined arterial approach using coils and Onyx liquid glue.

OUTCOMES

The patient's exophthalmos and congestion symptoms were improved.

CONCLUSION

DAS is the gold standard for the diagnose of CSDAVF. Intravascular embolization interventional therapy is an effective treatment for CSDAVF.