1. Inadvertent subdural injection: a complication of an epidural block;Lubenow;Anesth Analg,1988
2. Extradural block. Confirmation of the injection site by x-ray monitoring;Mehta;Anaesthesia,1985
3. Accidental subdural injection during attempted lumbar epidural block may present as a failed or inadequate block: radiographic evidence;Collier;Reg Anesth Pain Med,2004
4. The incidence of Horner's syndrome during lumbar extradural for elective caesarean section and provision of analgesia during labour;Clayton;Anaesthesia,1983
5. Bilateral Horner's syndrome and hoarseness complicating lumbar epidural anesthesia;Tabatabia;Reg Anesth,1989