Letter to the Editor In Reply to “Does Spinal Cord Line Influence Choice of Surgical Approach in Multilevel Cervical Spondylotic Myelopathy?” you very much to the reviewer for his letter and advice in T hank regard to our article, “The Spinal Cord Line Can Predict Postoperative Recovery Effect for Multilevel Cervical Spondylotic Myelopathy.”1 It is a great honor to have an exchange of communications with him. We agree with his viewpoint on defining the starting and end points of the spinal cord (SC) line. Point A was the posteroinferior point of the spinal cord at C2, whereas point B was the posterosuperior point of the spinal cord at C7. We meant that these points were the anterior cord adjacent to the vertebral body in a lordotic spine (Figure 1).1 The description of the reviewer may be more exact. The modified K line was defined by Sun et al.2 as a line connecting both anterior points of the spinal cord at the level of the endplates of inferior vertebrae C2 and C7 on sagittal T1-weighted magnetic resonance imaging. This was similar to, but different from, the SC line. Chen et al.3 found that surgical outcomes were poorer in patients with T2 intramedullary signal changes, especially when the signal changes were multisegmental and had a well-defined border and T1 intramedullary signal changes. We studied the SC line on T2 magnetic resonance imaging and thus did not mention T1 signal changes. The surgical strategy selected depended on multiple factors, such as the patient’s age, patient’s health condition, amount of compressed levels, severity of cervical stenosis, adjacent segment degeneration, and cervical sagittal alignment and stability.4 The age of type I, type II, and type III patients did not differ

1008

www.SCIENCEDIRECT.com

significantly. The SC line took into account the relationship between the spinal cord curvature and the degree of compression. We agree with the reviewer that the follow-up period of 1 year is relatively short; a study with long-term follow-up is underway. We hypothesize that the anterior approach is the preferred method of treatment for type I patients with surgical segments