Shah SH, Chen YF, Moss HE, et al. - This study was carried out to establish a predictive model based on known preoperative risk factors for perioperative ischemic optic neuropathy (ION) to guide patient and physician preoperative decision-making. Researchers distinguished and classified the National Inpatient Sample (NIS) for 1998–2012, discharges for posterior thoracic, lumbar, and sacral spine fusion by ION status. They conducted hierarchical clustering with 4 clusters, and the variable with largest squared loading in each cluster was chosen. In spine fusion, it was noted that predictive model could enable screening for individuals at higher risk of ION to give more accurate risk assessment and surgical and anesthetic planning for perioperative ION.