Study: Despite its reputation, spinal angio is safe, accurate
Spinal digital subtraction angiography (SpDSA) carries a very low risk of complications, and provides the imaging gold standard for the evaluation of spinal cord disorders, according to a study published online Sept. 14 in Neurology. The results contradict the perception of SpDSA as a high-risk procedure that requires high doses of radiation and contrast.

Timely and accurate diagnosis of diseases involving the spinal cord vasculature is critical, yet challenging. Clinical symptoms are nonspecific, but misdiagnosis or delayed diagnosis can lead to worsening myelopathy.

While there have been advances in spinal cord vascular imaging, SpDSA remains the gold standard. However, it is perceived as a high-risk study.

James Chen, BS, and Philippe Gailloud, MD, from the division of interventional neurology at Johns Hopkins School of Medicine in Baltimore, sought to provide an up-to-date assessment of the safety and diagnostic role of SpDSA.

The researchers retrospectively reviewed 302 diagnostic spinal angiograms acquired between January 2000 and December 2010 at Johns Hopkins. They reported no intraprocedural or postprocedural neurologic complications. Both patients who experienced non-neurologic complications were released at baseline status.

SpDSA was used to diagnose a variety of vascular malformations, including: spinal dural arteriovenous fistulas (AVF), perimedullary AVFs, arteriovenous malformations and epidural AVFs.

Chen and Gailloud emphasized the need for an accurate diagnostic tool for spinal cord disorders, writing, “As the roles of both endovascular and microsurgical techniques for the treatment of spinal cord vascular malformations continue to increase, so does the need for detailed hemodynamic and anatomic analysis of spinal vessels at a level that can only currently be provided by catheter angiography.”

The current study demonstrates the favorable safety profile of SpDSA, which the authors partially credited to advances in imaging equipment and endovascular devices. They reported comparable contrast load requirements for CT angiography and SpDSA and a mean fluoroscopy time of 25 minutes, an improvement from earlier studies. The procedure also can be completed without general anesthesia, except among pediatric patients, Chen and Gailloud said.

The authors acknowledged that the retrospective design of the study may have underestimated complication rates and made it challenging to assess delayed complications. They concluded, “Prompt referral for SpDSA offers the opportunity for earlier detection and improved functional recovery following therapy … SpDSA is able to confirm or exclude with a gold-standard level of certainty the presence of spinal vascular lesions, and therefore can play an important role in the evaluation of atypical or otherwise diagnostically challenging cases.”