RADIOGRAPHIC FINDINGS OF UNILATERAL EPIDURAL BLOCK

In 236 consecutive lumbar epidural anesthesia patients, epidurography was performed in seven patients who developed unilateral loss of cold sensation to clarify the cause of unilateral block. Epidurography demo nstrated the epidural catheter tip location in the anterior epidural s pace in four patients (57%) and in the transforaminal passage in three patients (43%). In all seven patients, successful bilateral epidural anesthesia was obtained by a second puncture using another catheter. O ur results showed that the most frequent cause of unilateral epidural blockade was the misplacement of the catheter into the anterior epidur al space.