title: Correspondence on BIP test.
authors: Vijah
authors: V
authors: Singh
authors: Michael  L
authors: M
authors: Whitworth
authors: Somayaji
authors: S
authors: Ramamurthy
mesh_terms: D004824:Epidural Space / Q000000981:diagnostic imaging / Q000601:surgery*; D005471:Fluoroscopy / Q000379:methods*; D006801:Humans; D007268:Injections, Epidural / Q000379:methods; D009339:Needles / Q000592:standards; D009407:Nerve Block / Q000379:methods*; D011312:Pressure