Carotid and transcranial color-coded duplex sonography in different types of carotid-cavernous fistula

Carotid cavernous fistula: A rare but treatable cause of ophthalmoplegia - A case report

Carotid cavernous fistulas (CCFs) are a rare but debilitating entity that may present with orbital or cerebral venous hypertension. CCFs may pose diagnostic and management pitfalls for clinicians as they can initially be misdiagnosed as primary orbital pathology or nonarteriovenous shunting-related cavernous sinus pathology. Furthermore, the resolution of pulsatile tinnitus could be an ominous sign in patients with untreated dural arteriovenous fistula. We describe a case of a 56-year-old male who presented with progressive right eye proptosis, congestion, decreased visual acuity, limited duction, exophthalmos, and pulsatile tinnitus. The patient had poor response to antibiotics and steroids. Magnetic resonance imaging brain showed significant inflammation involving the right orbit and atypical enhancement of the basal frontal lobe adjacent to the orbit. Cerebral angiography revealed an indirect right CCF and right sigmoid sinus thrombosis with stenosis of the right internal jugular vein. No clear predisposing factor was identified. Given the rapidly progressive nature of the condition, the patient successfully underwent endovascular treatment with transvenous approach to preserve flow in the internal carotid artery while ensuring occlusion of the fistula. A triad of proptosis, eye congestion, and signs of turbulent flow such as tinnitus or orbital bruit should raise suspicion for CCF. An interesting feature in this patient is that CCF may have occurred secondary to sigmoid sinus thrombosis with accompanying small cortical vein drainage. Our case highlights the importance of early recognition and timely intervention to ensure the resolution of orbital hypertension-related symptoms in rare cases of CCFs.

Objective Assessment of Arterial Steal Phenomenon in Direct Carotid Cavernous Fistula Using 2D Parametric Parenchymal Blood Flow Analysis

The aim of the study is to evaluate the hemodynamic changes and the parenchymal perfusion associated with carotid cavernous fistulas before and after embolization using two-dimensional (2D) parenchymal blood flow analysis. A 15-year-old boy presented with 2-month history of progressive right eye proptosis, chemosis, and diplopia after a motor vehicle accident. Intracranial liquid embolization using Onyx-18 through the inferior petrosal approach was done with balloon protection at the opening of the fistula in the internal carotid artery, resulting in complete occlusion of the fistula. Parenchymal blood flow analysis was done before and immediately after embolization. 2D parametric parenchymal blood flow analysis is newly introduced software that can provide data cannot be conveyed by conventional digital subtraction angiography alone. The software allows for objective assessment of the arterial steal and the parenchymal perfusion both pre, and post-embolization. Pre-embolization assessment may influence the therapeutic decision, while post-embolization assessment can evaluate the treatment efficacy.

Efficacy of Orbital Color Doppler Imaging and Neuroimaging in the Diagnosis of Carotid Cavernous Fistulas

PURPOSE

To evaluate the diagnostic sensitivity and specificity of orbital color Doppler imaging (CDI) and conventional neuroimaging (CT/MRI) compared with cerebral angiography in patients with carotid-cavernous fistulas (CCFs).

METHODS

The study design was a retrospective patient chart and imaging review. The authors reviewed 655 charts of all patients who underwent CDI and neuroimaging (CT/MRI) between 2006 and 2015 at one institution. Sixty patients had a presumptive diagnosis of CCF without thrombosis. Thirty-seven patients with 43 events met the inclusion criteria of the study. The diagnostic sensitivity of the 3 noninvasive imaging modalities (CDI, CT, MRI) for CCF was compared with the gold standard 6-vessel cerebral angiography. Significance testing was performed using the 2-tailed Fisher test.

RESULTS

Color Doppler imaging had high sensitivity (96.8%) but low specificity (41.7%) for the diagnosis of CCFs with anterior orbital findings. A negative CDI had more diagnostic value than a positive CDI. While an arterial wave form in the superior ophthalmic vein was the most common finding of CCF on CDI, enlargement of the superior ophthalmic vein was the only statistically significant finding. Posterior cortical venous drainage was noted in about 10% of the patients with indirect (low-flow) fistulas, who presented with unilateral orbital signs and symptoms, a finding not previously reported in the literature.

CONCLUSION

Color Doppler imaging is a useful noninvasive, radiation-free modality for diagnosis of CCF with anterior drainage, with higher sensitivity than CT or MRI, but equivalent specificity. A significant limitation of CDI is the lack of usefulness in diagnosing fistulas with posterior cortical venous drainage, which carry a risk of intracerebral hemorrhage and stroke. In this series, 10% of unilateral CCFs with anterior orbital signs and symptoms showed angiographic evidence of posterior cortical venous drainage.

Assessment of dural arteriovenous fistulas of the cavernous sinuses on 3D dynamic MR angiography

BACKGROUND AND PURPOSE

Flow voids within the cavernous sinuses and/or certain venous drainage on spin-echo MR imaging and time-of-flight (TOF) flow enhancement on MR angiography (MRA) have indicated high-velocity shunt flow and have been used for screening patients with dural arteriovenous fistulas (DAVFs) of the cavernous sinuses. In this investigation, the capabilities of 3D dynamic MRA as a flow-independent approach and those of conventional MR imaging techniques were compared with selective angiography for the diagnosis of DAVFs of the cavernous sinuses.

MATERIALS AND METHODS

This retrospective study involved 18 patients with angiographically proved DAVFs of the cavernous sinuses and 12 control subjects. Sixteen partially overlapping sequential MR images were acquired on contrast-enhanced 3D dynamic MRA between the petrosal bone and the orbital roof. Two experienced observers blinded to the clinical data and results of angiography independently graded 3D dynamic MRA, fast spin-echo T2-weighted imaging (FSE T2WI), and TOF MRA.

RESULTS

The average area under the receiver operating characteristic curve values and interobserver kappa scores for the diagnosis of DAVFs on 3D dynamic MRA, FSE T2WI, and TOF MRA were 0.99, 0.89, and 0.95; and 0.92, 0.71, and 0.73, respectively. Those for the diagnosis of anterior, posterior, and retrograde cortical venous drainage on 3D dynamic MRA were 0.72, 0.95, and 0.81; and 0.56, 0.50, and 0.49, respectively.

CONCLUSION

In this small series, screening 3D dynamic MRA directly demonstrates DAVFs of the cavernous sinuses and has improved diagnostic capability.

Pulsatile tinnitus in a case of traumatic temporal extradural arteriovenous fistula: carotid duplex sonography findings before and after embolization

Carotid duplex sonography (CDS) is regarded as a screening tool for lateral dural arteriovenous fistulae (AVF). However, data on evaluating long-term effects of endovascular treatment are limited. We report the CDS findings in the feeding arteries of a traumatic temporal extradural AVF before and after transarterial embolization. Volume flow of the left common carotid artery was greater than the right (433 ml/minute versus 294 ml/minute right) and the resistance index of the left external carotid artery was lower than the right (0.69 left versus 0.84 right). Both parameters returned to normal 4 months after embolization, thus confirming successful endovascular treatment.

Diagnóstico precoz no invasivo de la fístula carótido-cavernosa postraumática por dúplex transcraneal color. Análisis de 4 pacientes

Posttraumatic carotid-cavernous fistula (PtCCF) is an uncommon complication after cranioencephalic trauma. It is usually diagnosed with a cerebral arteriography when the clinical symptoms have already appeared. The transcranial color-coded duplex sonography (TCDS) is a non-invasive technique at the patient's bedside that permits visualization of the circle of Willis and the intracavernous segment of the internal carotid artery. The initial sonographic patterns that suggest the presence of a PtCCF by TCDS are a mosaic image in color mode, presence of arterial and venous flows mixed with high velocity and low resistances. We present our experience in the early and non-invasive diagnosis of PtCFF in an Intensive Care Unit.

[Carotido-cavernous fistula after traumatic brain injury: an unusual vascular complication]

The authors reported the case of a young man who suffered a cranial traumatism and showed neurological, ophthalmic and orbital signs with orbital bruit, cranial nerve palsy and chemosis while he was in the intensive care unit. Further examinations of imagery made it possible to highlight a high-flow carotid-cavernous fistula which was the origin of these symptoms and which was successfully treated by endovascular way. The aim of this article is to remind the reader of the characteristics of this pathology, in terms of epidemiology, physiopathology, clinical and paraclinical presentation, and therapeutic care.

Diagnosis and follow-up study of carotid cavernous fistulas with color Doppler ultrasonography: analysis of 33 cases

OBJECTIVE

The purpose of this study was to observe image characteristics and hemodynamic changes of carotid-cavernous sinus fistulas (CCFs) and to evaluate the efficacy of interventional treatment for CCFs by color Doppler ultrasonography (CDUS).

METHODS

Thirty-three patients with suspected CCFs were studied with CDUS. Forty-six volunteers took part in this study as controls. Scanning was performed through temporal, orbital, and occipital windows to measure the blood flow parameters of the internal carotid artery (ICA) and related vessels. All results were confirmed by cerebral angiography. Nineteen patients were followed after interventional treatment.

RESULTS

Thirty-two patients (97%) were found to have CCFs by CDUS. Irregular mosaic flashes were observed in the cavernous sinus region, the cross-section areas of which were significantly larger than those of the normal intracranial ICA (1.7-5.2 versus 0.2-0.5 cm(2); P < .01). A lower resistive index of the ICA in the affected side was revealed with spectral analysis of relevant vessels. The peak velocity of vessels distal to the fistula was significantly lower than that of the healthy side and control group (P < .05). Superior ophthalmic veins had a reversed arterialized flow pattern with a mean velocity of 34.5 cm/s and an average resistive index +/- SD of 0.31 +/- 0.08. In follow-up study, the mosaic flashes and turbulence flow disappeared in 14 patients and remained in 5 after the interventional operation.

CONCLUSIONS

Combined with the direct sign of an irregular mosaic flash in the cavernous sinus region, hemodynamic changes in relevant branch vessels, and a reversed arterialized flow pattern in superior ophthalmic veins, CDUS has great value in confirming diagnosis and follow-up study of CCFs.

Diagnosis of intracranial dural arteriovenous fistulas by carotid duplex sonography

OBJECTIVE

To validate carotid duplex sonography (CDS) in diagnosis of intracranial dural arteriovenous fistulas (AVFs) against the standard of cerebral catheter angiography.

METHODS

We investigated 35 patients with dural AVFs and 64 patients without dural AVFs confirmed by the catheter angiographic studies. Twenty CDS parameters in 4 categories, including resistive index (RI), flow volume, peak systolic velocity, and end-diastolic velocity, were evaluated. Abnormal CDS findings were defined as the data above 95th percentile or below 5th percentile values from 180 control subjects. We determined the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in each CDS parameter.

RESULTS

The parameter of RI of the external carotid artery (ECA; cutoff points: right, 0.72; left, 0.71) yielded the highest sensitivity (74%), specificity (89%), positive predictive value (79%), negative predictive value (86%), and accuracy (84%) for predicting dural AVFs. All other ECA-related parameters yielded sensitivity lower than 70%, and those related to the internal carotid artery were lower than 30%. The sensitivity values for the parameter of RI of the ECA in different locations of dural AVFs were 54% (7 of 13 patients) in cavernous sinus dural AVFs and 86% (19 of 22 patients) in non-cavernous sinus dural AVFs (P = .05).

CONCLUSIONS

The RI of the ECA is the best CDS parameter for predicting intracranial dural AVFs. Carotid duplex sonography can be used as the initial screening tool for diagnosis in patients having symptoms related to dural AVFs.

Diagnóstico por dúplex transcraneal color de una fístula carótido-cavernosa traumática

The extracranial carotid duplex is a feasible, non invasive technique that is useful for the diagnosis of some intracranial pathologies. We present the case of a patient who was admitted in our unit with a severe traumatic brain injury. An early transcranial color duplex showed a mosaic color flash with unidirectional turbulent flow that was compatible with a posttraumatic carotid cavernous fistula that was confirmed by angio MRI.

Visualization of bilateral carotid cavernous sinus fistulas with duplex sonography

Duplex sonography used as a primary diagnostic tool in the case of a 17-year-old boy with a traumatic head injury revealed bilateral carotid cavernous sinus fistulas, with bilateral dilated venous convolutions next to the carotid siphon and dilated superior ophthalmic veins. A bilateral craniectomy allowed visualization of the entire circle of Willis together with the dilated cavernous sinuses. Doppler spectral analysis of blood flow in the arterialized superior ophthalmic veins revealed an arterialized venous pattern with retrograde and increased blood flow. The same blood flow profile was found in the venous cavernous sinuses. These findings were confirmed by digital subtraction angiography. We planned to perform embolization of the patient's fistulas, but intracranial and subarachnoid hemorrhaging developed, and the patient died the day before the procedure was to have been performed. The entire pathologic state of carotid cavernous sinus fistulas, from their origin beside the carotid siphon to the superior ophthalmic veins, can be visualized with duplex sonography, particularly when patients have undergone craniectomy. We believe that patients with frontal or basilar skull fracture should undergo duplex sonographic examination to detect carotid cavernous sinus fistulas.

Transcranial ultrasonography of cerebral veins and sinuses

Transcranial ultrasonography has become a valuable diagnostic tool for the bed-side evaluation of cerebral hemodynamics. While the assessment of arterial blood flow is well established, analysis of venous hemodynamics by transcranial ultrasonography is a new application of the method. The present review summarises the current state of transcranial venous ultrasound in adults by means of transcranial Doppler (TCD) and transcranial colour-coded duplex sonography (TCCS). It gives a critical overview regarding current and possible future clinical applications of the techniques.