The primary objective of this review of the literature is to identify the probable causes of blindness after bilateral radical neck dissections. This case report and literature review also discusses possible preventive measures that may avert this catastrophic outcome. Cases of blindness after bilateral radical neck dissection were identified by an electronic literature search, as well as cross-checking all references of the above-identified papers. Eleven previous cases of blindness after bilateral neck dissection were identified. The most common cause was posterior ischemic optic neuropathy (PION), which was permanent. We present the only case in the literature in which blindness occurred after radical neck dissections separated by a span of 9 years. The cause of blindness in our patient was posterior ischemic optic neuropathy. Contributing factors included anemia, hypotension, and disruption of collateral venous return from the neck.