Abstract 016: Endovascular Coiling of a Left L3 Radicular Artery Mycotic Aneurysm
Authors: Roberts William H , Tong Brian A , Giurgiutiu Dan‐Victor 
Published: March 2024

Introduction
Mycotic aneurysms of paraspinal arteries are a rare finding. The most commonly affected vessels include the aorta, iliac, visceral, femoral, brachial, and cerebral arteries, often occurring in the setting of bacteremia, direct invasion from local infection, septic emboli from infective endocarditis, or arterial trauma.¹⁻³ However, there is limited existing documentation of mycotic aneurysms of the spinal vasculature.² Furthermore, knowledge regarding the management of paraspinal mycotic aneurysms and the efficacy of endovascular repair of these lesions is scarce.⁴

Methods
We present a 51‐year‐old male with a past medical history of diabetes mellitus, end‐stage renal disease on hemodialysis (T/T/S), hypertension, congestive heart failure, peripheral arterial disease s/p right bilateral knee amputation, coronary artery disease, and epilepsy that presented with a 2‐week duration of severe low back pain with associated left upper and lower extremity numbness, subjective fevers, generalized weakness, diffuse abdominal pain, nausea and vomiting. Neurological exam on admission was remarkable for left lower extremity paresthesia of no clear dermatomal distribution with no other focal deficits. CT of the abdomen and pelvis revealed concern for L3‐L4 discitis and osteomyelitis and a greater than 3 cm homogeneously enhancing lesion within the paraspinal muscles of the same level concerning for neoplasm vs. vascular malformation vs. pseudoaneurysm (Figure 1A). An emergent MRI lumbar spine revealed a left L3 radicular artery saccular aneurysm concerning for a mycotic aneurysm in the setting of infection (Figure 1B).

Results
Patient underwent cerebral and spinal angiography which showed a left L3 radicular artery ruptured mycotic aneurysm measuring 11.26 x 6.5 mm in mediolateral and craniocaudal diameters associated with a 16.4 x 21 mm pseudoaneurysm (Figure 1C). Successful coiling of the aneurysm, pseudoaneurysm, and fistulous connection were performed with Penumbra 400 coils and PAC coils. There was no opacification of the aneurysms at the end of the procedure and no procedural complications (Figure 1D). CT‐guided biopsy of the L3‐L4 disc was also obtained. Postoperatively, the patient was hypertensive to a systolic blood pressure of 220 mmHg that was controlled with a nicardipine infusion that was gradually weaned off once the patient’s vitals were stable while in the Neuro‐ICU. The patient’s discitis and osteomyelitis were identified as the source of infection for the aneurysm and managed medically with IV antibiotics and analgesics with no need for any acute neurosurgical intervention. Blood cultures showed no growth throughout admission and biopsy of lumbar vertebrae showed normal skin flora. Patient with stable neurological exam throughout his stay. Patient was transferred to the floor before ultimately discharging home per patient preference.

Conclusion
Endovascular embolization is a potentially efficacious therapy for the management of mycotic aneurysms of the spinal vasculature. Endovascular repair has been demonstrated as a surgical option for mycotic aneurysms in other vessels, such as the aorta, but further research and replication are needed to establish the utility of coiling in the setting of paraspinal mycotic aneurysms.⁵⁻⁷