title: Reply to Drs Wolf and Gray.
authors.affiliation: Department of Anesthesia and Intensive Care The Chinese University of Hong Kong Prince of Wales Hospital Shatin, New Territories, Hong Kong Special Administrative Region, China Department of Anesthesiology St Luke's-Roosevelt Hospital Center New York, NY Department of Anaesthesiology Mahidol University, Sriraj Hospital Bangkok, Thailand Department of Anesthesiology St. Luke's-Roosevelt Hospital Center New York, NY.
authors.forename: Manoj Kumar
authors.initials: MK
authors.lastname: Karmakar
authors.forename: Ali Nima
authors.initials: AN
authors.lastname: Shariat
authors.forename: Pawinee
authors.initials: P
authors.lastname: Pangthipampai
authors.forename: Junping
authors.initials: J
authors.lastname: Chen
mesh_terms: D005205:Fascia / Q000000981:diagnostic imaging*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging*; D012584:Sciatic Nerve / Q000000981:diagnostic imaging*; D018084:Ultrasonography, Interventional / Q000379:methods*