Masaaki Machino1, Kei Ando1, Kazuyoshi Kobayashi1, Kyotaro Ota1, Masayoshi Morozumi1, Satoshi Tanaka1, Keigo Ito2, Fumihiko Kato2, Naoki Ishiguro1, Shiro Imagama3. 1. Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan. 2. Department of Orthopedic Surgery and Radiology, Chubu Rosai Hospital, Japan Organization of Occupational Health and Safety, Nagoya, Japan. 3. Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan. Electronic address: imagama@med.nagoya-u.ac.jp.
Abstract
OBJECTIVES: Although patients with cervical spinal cord injury without radiographic abnormality (SCIWORA) present increased signal intensity (ISI) on magnetic resonance imaging (MRI), its degree has not been examined. This study evaluated the clinical effectiveness of MRI-based ISI in adult patients of SCIWORA. Its predictive value for symptom severity was also evaluated. PATIENTS AND METHODS: One-hundred consecutive SCIWORA patients who had undergone expansive laminoplasty were enrolled. Among them, 79 were male and 21 were female. The mean age was 55 years (range 20-87). All patients underwent MRI in the acute phase, and ISI was classified into three groups based on sagittal T2-weighted MRI: Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score) and the ASIA impairment scale (AIS). RESULTS: Preoperative MRI showed Grade 0 in 8 patients, Grade 1 in 49 patients, and Grade 2 in 43 patients. There were no differences in age and gender among three groups. The pre- and postoperative JOA scores decreased significantly with an increasing ISI grade. The recovery rate of JOA score decreased with the ISI grade. The ISI grade tended to increase with the pre- and postoperative AIS grades. ISI Grade 2 on MRI was observed in severely paralyzed cases. CONCLUSIONS: MRI-based ISI classification is correlated with preoperative symptom severity in adult patients with SCIWORA and can be a predictor of surgical outcome.
OBJECTIVES: Although patients with cervical spinal cord injury without radiographic abnormality (SCIWORA) present increased signal intensity (ISI) on magnetic resonance imaging (MRI), its degree has not been examined. This study evaluated the clinical effectiveness of MRI-based ISI in adult patients of SCIWORA. Its predictive value for symptom severity was also evaluated. PATIENTS AND METHODS: One-hundred consecutive SCIWORA patients who had undergone expansive laminoplasty were enrolled. Among them, 79 were male and 21 were female. The mean age was 55 years (range 20-87). All patients underwent MRI in the acute phase, and ISI was classified into three groups based on sagittal T2-weighted MRI: Grade 0, none; Grade 1, light (obscure); and Grade 2, intense (bright). The pre- and postoperative neurological status was evaluated using the Japanese Orthopaedic Association scoring system for cervical myelopathy (JOA score) and the ASIA impairment scale (AIS). RESULTS: Preoperative MRI showed Grade 0 in 8 patients, Grade 1 in 49 patients, and Grade 2 in 43 patients. There were no differences in age and gender among three groups. The pre- and postoperative JOA scores decreased significantly with an increasing ISI grade. The recovery rate of JOA score decreased with the ISI grade. The ISI grade tended to increase with the pre- and postoperative AIS grades. ISI Grade 2 on MRI was observed in severely paralyzed cases. CONCLUSIONS: MRI-based ISI classification is correlated with preoperative symptom severity in adult patients with SCIWORA and can be a predictor of surgical outcome.