| Objective: Multilevel cervical spondylotic myelopathy (MCSM) is the pathological change of over two cervical segments, which is characterized by extensive compression of spinal cords and seriously damaged nerves. The major expression is pyramidal tract symptom. It often affects the routine work and the lives of the patients seriously. The rapid development of imageological technology, esp, the availability of Magnetic resonance imaging (MRI) has played an important role in the diagnosis and cure of multilevel cervical spondylotic myelopathy, which has been treated widely with surgical operations, including anterior approach, posterior approach and anterior-posterior united approach. MRI is an important examination in patients with cervical spondylotic myelopathy. MRI can show not only the degree of spinal canal stenosis but also the intramedullary state of the spinal cord in detail. However, it is difficult to choose the appropriate approach despite the fact of widespread operative treatments. Reasonable choice of surgical method is the key to therapeutic efficacy. The imageology was always provided reliabilitical evidence for the diagnosis of cervical syndrome before. The aim of this research is to assess the clinical value of three approachs for multilevel cervical spondylotic myelopathy with classification of quantifying MRI T2 signal intensity ratio.Methods: From December 2000 to November 2007, 116 patients treated with anterior, posterior, or posterior-anterior combined surgery for multilevel cervical myelopathy were enrolled retrospectively in this study (including 86 males, 30 females, with the mean age of 58.73±8.29 years). 1.5 T magnetic resonance imaging (MRI) was performed on each patient before surgery. T1- and T2-weighted images of sagittal views of the cervical cord were obtained using a spin echo sequence system for T1-weighted images and a fast spin echo sequence system for T2-weighted images. A surface coil was used. The slice width was 4 mm and the acquisition matrix was 512×256. The sequence parameters were repetition time (TR) 612 milliseconds/echo time (TE) 13 milliseconds for T1-weighted images, and TR 2400 milliseconds/TE 114 milliseconds for T2-weighted images. Value of T2-weighted images (T2WI) of sagittal ISI on the cervical spinal cord were obtained, the regions of interest (ROIs) is taken by 0.05cm2. T2-weighted MR images of sagittal normal cord signal intensity value on the cervical between C7-T1 disc levels were obtained, and the ROIs are taken by 0.3 cm2. Signal intensity value is measured by computer and the signal ratio between regions 0.05 cm2 and 0.3 cm2 has been calculated. If no intramedullary ISI on T2-weighted MR images was noted, the ROIs will be taken by 0.05 cm2 of the severe compression cord.All patients were divided into three groups by the data of signal intensity ratio. Parameter of improvement rate to JOA score were studied in groups of different classification with signal intensity ratio and in groups of different surgical approach for all patients. Statistical analysis were performed with SPSS 13.0.Results: All patients were followed up for 1～5 years, with the average of 13.8 months. The JOA score in 116 patients was 8.68±2.26 preoperatively, and 12.89±2.94 three months postoperatively, 12.16±3.07 twelve months postoperatively. The mean recovery rate was 55.13%±15.27% at final follow-up. With the Kruskal-Wallis H test for recovery rate, in the group of low signal intensity ratio, there were no significant difference among three surgical approachs. In the group of middle signal intensity ratio, there showed significant difference among three surgical approachs. The Student-Newnan-Keuls test for recovery rate showed significant difference between groups of anterior (71%) and posterior (47%) decompression, posterior and posterior-anterior combined (64%) decompression. In the group of high signal intensity ratio, there also showed significant difference among three surgical approachs. The SNK test for recovery rate showed significant difference between groups of anterior (20%) and posterior (36%) decompression, anterior and posterior-anterior combined (28%) decompression. However, there was no significant difference among groups of three surgical approachs in all patients.Conclusion: Surgical decompression for multilevel cervical spondylotic myelopathy can significantly improve the neurological function. In the groups of different signal intensity grade, the three surgical approach showed different outcome. And the classification of quantifying MRI T2 signal intensity ratio can help to choose the surgical treatment.
|
PDF Full Text Request