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Transarterial CT angiography for surgical planning of spinal dural arteriovenous fistula.

OBJECTIVE
We report a novel method to provide excellent anatomical depiction of a dural arteriovenous fistula (dAVF) for surgical planning.


METHODS
A 78-year-old female presented with progressive back pain, deteriorating mobility and urinary incontinence with a background of obesity and severe osteoarthritis. Initial MRI suspected dAVF and subsequent spinal angiography encountered an extremely tortuous and arteriosclerotic aorta, hence catheterisation of the segmental-intercostal and lumbar vessels proved challenging. Contrast injection into the aortic arch via a pigtail catheter for arterial-phase CT angiogram of the descending aorta was performed.


RESULTS
This modality of imaging delineated the dAVF showing extensive involvement of the whole spine accounting for the patient's symptoms. Furthermore this allowed characterisation of bony anatomy in relation to the fistula facilitating precise surgical approach. The dAVF was successfully disconnected through a localised laminectomy centred over the lesion.


CONCLUSION
This specific technique for dAVF characterisation has not been previously reported, although trans-venous angiography has been used to some effect. In view of diagnostic and therapeutic technical difficulties that are often faced in such patients, this technique may be a useful alternative that is not only helpful in accurate diagnosis but helps in providing an invaluable guide for the surgical approach.


ADVANCES IN KNOWLEDGE
This case highlights the difficulties that one may be faced within cases of tortuous vasculature and the obese patient population. With this in mind, we have been able to demonstrate how a unique hybridised technique may provide valuable alternative to the neurosciences team should such a future scenario arise.