Prone positioning used for surgeries in operation room has been reported with ocular complications, of which vision loss is one of the devastating complications. Multiple risk factors are reported but orbital compression during prone positioning, excess intravenous fluids, hypotension and duration of prone positioning were the predominant factors. Perioperatively patients, who underwent prone positioning for surgeries can be followed up for symptoms of any complications after the surgery, but this follow up for symptoms is difficult in intensive care units as most of the patients after prone ventilation, will not be able to communicate. The hours of prone ventilation are nearly 3-4 times more, when compared intra-operatively which can definitely increase intra-ocular pressure(IOP) significantly. Most of the patients will be hemodynamically unstable on vasopressor supports, unlike intra-operatively, which can significantly affect ocular perfusion pressure (mean arterial pressure - intra-ocular pressure), making ICU patients with definitely high risk for ocular complication. The purpose of our study is to evaluate the effect of prone position on IOP in critically ill patients and follow up for other ocular complication among survivors.