Wednesday, September 26, 2018 10:35 AM – 12:00 PM Cervical Spine Trauma: 18. The relationship between subacute MRI and walking ability, urinary function at the chronic stage in patients with cervical spinal cord injury

Abstract

BACKGROUND CONTEXT Some papers reported about the relationship between the MRI features and the clinical outcomes in patients with cervical spinal cord injury (CSCI) at the acute stage following trauma. However, to the best of our knowledge, there is no paper reporting about the relationship between MRI features and activities of daily living of patients at chronic stage. PURPOSE The purpose of this study was to investigate the relationship between the subacute MRI features and the clinical outcomes at chronic stages, especially walking ability and urinary function in patients with cervical spinal cord injury (CSCI). STUDY DESIGN/SETTING A retrospective imaging and clinical study. PATIENT SAMPLE Eighty-six patients with CSCI who were admitted to our hospital within 7 days after injury were included in this study. The diagnosis was 66 patients for CSCI without major bone injury and 20 patients for CSCI with fracture or dislocation. Seventy-two males and 14 females, and the average age at the time of injury were 62.2 years (16-88 years). Paralysis at the time of admission was graded as A in 25, B in 7, C in 32, and D in 22 patients on the basis of the ASIA impairment scale. OUTCOME MEASURES Patients were followed up for average 7.5 months (range, 4-14 months). MRI was performed for all patients at within 24 hours after admission (acute stage) and 1 month following injury (subacute stage). Using the MRI sagittal images, we measured the vertical and transverse diameter of intramedullary intensity changed area with T1 and T2-weighted images at the injured segment. Neurological evaluation was performed using ASIA motor score, the modified Frankel grade and urination status at the time of admission, 1 month, and 6 months following injury. METHODS We evaluated the relationship between the size of intensity-changed area in MR images (T1 low and T2 high intensity areas) and ASIA motor score, walking ability and urinary function. This study was approved by our Institutional Review Board, and written informed consent was obtained from all the patients. RESULTS In the MR images at subacute stage, T1 low-intensity area, which was not seen at acute stage, appeared in 73 (84.8%) in 86 patients. There was a significant relationship between the transverse diameter of T1 low-intensity area in MR image at subacute stage and walking ability, urination function at 6 months following injury. ASIA motor score at admission also showed a significant correlation with walking ability, urination function at 6 months following injury. Receiver operator characteristic (ROC) curve analysis demonstrated that the optimal transverse diameter of T1 low-intensity area cut-off value for patients who were able to walk with or without a cane at 6 months following injury was 46%. The optimal transverse diameter of T1 low-intensity area cut-off value for patients who were able to self-urinate at 6 months following injury was 30%. ROC curve analysis demonstrated that the optimal ASIA motor score at admission cut-off value for patients who were able to walk with or without a cane at 6 months following injury was 46. The optimal ASIA motor score at admission cut-off value for patients who were able to self-urinate at 6 months following injury was 50. Twenty of the 21 patients (95.2%) with no or less than 1/3 of the cord transverse diameter of T1 low-intensity area, and with admission ASIA motor score 50 or more recovered able to walk with or without a cane, and able to self-urinate at 6 months following injury. CONCLUSIONS The ASIA motor score at admission and subacute T1 low-intensity area were significantly correlated with the walking ability and urination function of the patient at 6 months following injury. With this data, we can infer the activities of daily living of patients at chronic stage and educate patients. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.