A 65-year-old woman underwent abdominal aortic replacement using a woven Dacron tube graft for abdominal aortic aneurysm on April 2nd, 1996. She had pyrexia on the 6th postoperative day and abdominal enhanced CT scan showed periprosthetic bubble formations. She underwent relaparotomy 14 days after the initial procedure due to large retroperitoneal abcess bacterial culture of which revealed methicillin resistant staphylococcus aureus. She underwent debridement and local irrigation by an electrolyzed strong acid solution. Her pyrexia diminished immediately after relaparotomy and bacterial culture of the drain of the left retroperitoneal space became negative 82 days later. She was discharged and has had no active inflammatory signs for 3 years. She is doing well at present.

The patient was a 61-year-old male, who underwent thoracoabdominal aortic aneurysm repair with Gelseal Triaxial prosthetic graft 2 years previously. False-aneurysm due to prosthetic graft dilatation was diagnosed. The direct closure of the ostium of the disruption of the anastomosis was successfully performed by an emergency operation. The postoperative course was uneventful. This case suggests that prosthetic graft dilatation may cause false-aneurysm at the site of end-to-side anastomosis.