Microvascular Perfusion Patterns and Intramedullary Arterial Resistance in Predicting Postoperative Recovery of Patients with Degenerative Cervical Myelopathy.

BACKGROUND AND PURPOSE: In patients with degenerative cervical myelopathy (DCM), spinal microvascular perfusion and intramedullary pressure are of crucial importance in predicting the postoperative recovery (PR). The aim of this study is to investigate whether intraoperative contrast-enhanced ultrasound (IO-CEUS) perfusion pattern and intramedullary arterial resistance could indirectly reflect spinal cord perfusion pressure and intramedullary pressure to predict PR in patients with DCM. MATERIALS AND METHODS: Patients with multilevel DCM who underwent French-door laminoplasty with ultrasound guidance from October 2019 to May 2022 were enrolled in this single-center prospective study. The modified Japanese Orthopaedic Association (mJOA) score was used to evaluate neurological function before and 12 months after operation. IO-CEUS perfusion patterns were classified into three types: Type I (visible central spinal artery, CSA, with clear arborization), Type II (diffuse homogeneous enhancement), and Type III (diffuse sparse enhancement), and the PR differences among the three types were compared. For those patients whose central spinal artery (CSA) Resistance Index (RI) could be measured, the correlation between the RI and PR was analyzed. RESULTS: Thirty patients were successfully included in the study (22 males and 8 females, with age at surgery was 56.47 ± 9.77 years). The mean recovery rate (RR) was 65.81±29.45%. There was statistical difference between type I and III (P = 0.01), but no significant difference between type I and II (P = 0.47) or between type II and III (P = 0.14). CSA RI was measurable in 21 of the 30 patients and was significantly negatively correlated with postoperative mJOA score (P = 0.03). CONCLUSIONS: IOUS can be used as a non-invasive method to predict the postoperative recovery (PR) of DCM patients by indirectly assessing spinal cord perfusion pressure and intramedullary pressure. Type I (visible CSA) perfusion pattern may be associated with favorable outcomes, while type III (diffuse sparse) perfusion pattern may forebode poor PR. Elevated RI of CSA may indicate increased risk of incomplete neurological restoration.