Sublingual Nitroglycerin Administration before Computed Tomography Angiography for Detection of the Artery of Adamkiewicz in Patients with Spinal Dural Arteriovenous Fistula.

Objective: Presurgical identification of the artery of Adamkiewicz (AKA) is crucial in thoracic and lumbar spinal lesions. Although CTA is widely employed to identify AKA, the detection rate varies across reports and is often difficult, especially in patients with spinal dural arteriovenous fistulas (SDAVFs). We report 2 cases where sublingual administration of nitroglycerin (NTG), a vasodilator, before CTA enabled good visualization of the AKA in patients with SDAVF. Case Presentation: (Case 1) A patient in his 60s presented with progressive gait disturbance, and an MRI revealed a spinal vascular lesion. CTA with sublingual NTG administration revealed an SDAVF supplied by the right seventh intercostal artery and an AKA branching from the left ninth intercostal artery. A chronic descending aortic dissection was identified on CTA, but spinal angiography was not performed. The patient was successfully managed with direct surgical disconnection of the SDAVF, and his symptoms improved. (Case 2) A patient in his 60s presented with progressive bilateral lower-limb numbness, and a thoracic SDAVF was diagnosed using MRI. CTA without NTG administration failed to identify the AKA, but after the administration of NTG, a clear depiction of the AKA branching from the left 10th intercostal artery was obtained. Endovascular shunt occlusion was successfully performed via the right 10th intercostal artery, resulting in significant symptom improvement. Conclusion: Sublingual NTG administration before CTA may improve AKA expression in patients with SDAVF.