1. Faculty of Medicine, Benha University, Benha 13511, Egypt
2. Faculty of Medicine, Menoufia University, Shiben El Kom 51123, Egypt
3. Department of Anesthesiology, Faculty of Medicine, Ain Shams University, Cairo 11517, Egypt
4. Department of Ophthalmology, University of Montreal, Montreal, QC H3T 1J4, Canada
5. School of Medicine, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA 71103, USA
6. Department of Anesthesiology, Louisiana State University Health Sciences Center at Shreveport, Shreveport, LA 71103, USA