Reversible postoperative vision loss (POVL): A tale of four patients.

Background: Posterior reversible encephalopathy syndrome (PRES) is a clinic-imaging entity. PRES is rarely reported in the perioperative period to cause reversible postoperative vision loss (POVL). It is reported in the literature in the form of case reports for spinal and cardiac surgeries and eclampsia patients. The suggested diagnostic criteria for PRES are: (i) acute onset of neurological symptoms and signs; (ii) specific findings of vasogenic cerebral edema upon imaging studies; and (iii) reversibility of signs and symptoms as well as image study findings. We report a case series of four patients undergoing other than spinal, cardiac, or orthopedic surgeries who developed PRES and had reversible POVL. Cases: The first case was a young female who had laparoscopic sleeve gastrectomy, had extreme hypertension at induction of anesthesia, had surgery and developed POVL after a few hours in the postoperative period, and had convulsions diagnosed to have PRES after computed tomography (CT) and magnetic resonance imaging (MRI). Managed with blood pressure and seizure control, vision returned gradually from 2nd postoperative day. The second case was also a young female who had appendicitis, requiring an appendectomy. Complicated by septic shock. Post-surgery, she was extubated after 1 day and immediately complained of total blindness. Local causes were ruled out, and an MRI diagnosed PRES. With supportive therapy, her vision started to return by Day 3 with improved normal vision. The third case was a female with recently diagnosed diabetes mellitus who presented with right upper limb embolic ischemia and had an embolectomy with a return of circulation. Her blood pressure was high and reached up to 200 mmHg after induction of anesthesia, which was controlled with deep anesthesia and a labetalol infusion in the perioperative period. After 8 h in the postoperative period, she was awake but searching for available objects. Relatives complained that she was unable to see. Local and fundus examinations were normal. She was awake but blind. Imaging studies confirmed PRES. Blood pressure was controlled using a labetalol infusion and continued supportive therapy. By Day 3, her vision became normal. The fourth case was an elderly patient who had hypertension, type 2 diabetes mellitus, and coronary artery disease. He underwent a right carotid endarterectomy under general anesthesia. He had severe hypertension in the perioperative area and blood pressure was controlled using a labetalol infusion. The surgery went smoothly. After 3 h, he had a loss of vision. Imaging studies confirmed PRES. His blood pressure was kept normal. After 2 days, his vision gradually returned to normal. Follow-up MRIs in the outpatient clinic for all four patients normalized in due time. Conclusion: Extremes of hypertension and/or hypotension in the perioperative period can cause PRES, which may lead to reversible POVL.