Diagnosis of traumatic carotid-cavernous sinus fistula by monitoring venous oxygen saturation in the jugular bulb: report of two cases

MR susceptometry for measuring global brain oxygen extraction

Monitoring of oxygen saturation in jugular venous blood gives an estimate of the balance of global oxygen delivery and cerebral oxygen consumption. We present a noninvasive approach to measure oxygen saturation in vivo in the internal jugular vein using MR susceptometry by exploiting the characteristic susceptibility of deoxyhemoglobin, and demonstrate the feasibility of performing such measurements in a group of subjects. We assessed the sensitivity of the method for detecting small changes in oxygen saturation by monitoring the variations observed during breath-holding and hypoventilation experiments. Unlike alternative methods, the susceptometric technique does not require calibration.

Marked regional heterogeneity in venous oxygen saturation in severe head injury studied by superselective intracranial venous sampling: case report

OBJECTIVE

Continuous monitoring of jugular venous oxygen saturation (SjvO2) is useful in the management of severe head injury. Abnormally high SjvO2 values can be caused by increased cerebral blood flow, decreased cerebral metabolism, brain death, contamination from extracerebral venous blood, or traumatic arteriovenous fistula.

CLINICAL PRESENTATION

A 20-year-old man with severe head injury was diagnosed to have a traumatic dural carotid-cavernous sinus fistula on the day of trauma. Continuous left SjvO2 monitoring from Days 4 to 12 revealed oxygen saturation ranging between 85 and 98%.

INTERVENTION

Superselective intracranial and extracranial venous sampling on Day 5 demonstrated marked regional heterogeneity in venous oxygen saturation as follows: superior sagittal sinus, 95 to 97%; straight sinus, 88%; right transverse sinus, 94%; left transverse sinus, 74%; right SjvO2, 95%; left SjvO2, 89%; the basilar plexus, 99%; right internal jugular vein, 98%; the left internal jugular vein, 94%. Extremely high oxygen saturation in the superior sagittal sinus and basilar plexus was attributed to severe brain damage and carotid-cavernous sinus fistula, respectively.

CONCLUSION

Although jugular bulb oximetry is useful in the management of severe head injury, high oxygen saturation values should be interpreted with caution because they cannot show the intracranial heterogeneity of venous oxygen saturation.

Posttraumatic carotid cavernous fistula: frequency analysis of signs, symptoms, and disability outcomes after angiographic embolization

OBJECTIVE

To increase awareness and understanding of posttraumatic carotid cavernous fistula (PTCCF) with the intent to expedite diagnosis and treatment of this disabling injury, a 14-year retrospective review of patients with angiographically identified PTCCF was conducted at this Level I trauma center. A frequency analysis of signs, symptoms, and disability was performed. The impact on disability of demographics, number of embolization attempts required for closure of the PTCCF, and time from injury to diagnosis was assessed by t test for independent samples.

RESULTS

Nine patients were diagnosed with 10 PTCCFs. Mean patient age was 41.5 years. All patients with PTCCF had basilar skull fracture, loss of consciousness, bruit, and chemosis; 90% had exophthalmos; 70% had visual changes; 50% complained of headache; and 80% had some lasting disability. Mean age of patients with partial to total disability was 47 years, while the mean age of patients without lasting disability was 19.5 years (p = 0.013). No statistical correlation could be found between disability and sex, blunt versus penetrating injury, days to diagnosis, or number of embolization attempts.

CONCLUSION

Patients sustaining head trauma with basilar skull fractures and presenting with the described signs and symptoms should be evaluated for PTCCF. Risk of disability does not appear to be influenced by number of attempts at embolization or time to diagnosis. However, age may have a significant impact on outcome.