Usefulness of Spinal MR Angiography for Detecting Adamkiewicz Artery

ABSTRACT

PURPOSE: We wanted to evaluate the detection rate of the artery of Adamkiewicz (AKA) by contrast-enhanced MR angiography (CE-MRA) and to compare the detection rate of AKA between the coronal source image plane and the sagittal source image plane. MATERIALS AND METHODS: Between December 2004 and May 2005, 23 patients (9 men and 14 women. age range 11-86 years, mean age 43 years) who were examined by contrast-enhanced MRI for the purpose of evaluating spondylopathy were also studied by performing spinal CE-MRA. Spinal CE-MRA was performed with a 1.5-T system and with using 3D Fast field echo with a double dose (0.2 mmol/kg) of Gadolinium. Source images were obtained in either the sagittal plane (n = 11) or the coronal plane (n = 12) at random. The source images were reconstructed with multiplanar reconstruction and maximum intensity projection. Two radiologists, who were kept unaware of the source image plane, independently evaluated the CE-MRA with focusing on the AKA. The detection rate was evaluated and the difference of detection rates according to the source image plane was compared and analyzed. RESULTS: CE-MRA could demonstrate the AKA in 11 (47%) of the 23 patients. The interobserver agreement for detection was fair (κ=0.283). Among the 11 patients in whom the MRA was obtained with using the coronal plane source image, CE-MRA detected the AKA in three of them (27%); among the 12 patients in whom the CE-MRA was obtained with using the sagittal plane source image, CE-MRA detected the AKA in 8 of them (67%, p = 0.059). The AKA in 7 cases (63%) originated from the intercostal or lumbar arteries on the left side at L2 (n = 3), L1 (n = 2), T12 (n = 1) or T9 (n = 1), and on the right side at L1 (n = 1) or T12 (n = 3). CE-MRA with coronal slice orientation visualized the AKA in 8 (67%) of the 11 patients (p = 0.059). CONCLUSION: The detection rate of AKA by CE-MRA was 47%. By obtaining the source image in the coronal plane, the detection rate of AKA was 67%.