ACUTE ABDOMEN ABNORMAL GAS COLLECTIONS TERRENCE C DEMOS, MD DEPARTMENT OF RADIOLOGY OR GAZ ACUTE ABDOMEN EXAMINATION • RADIOGRAPHS – – – – LEFT LATERAL DECUBITUS ABDOMEN UPRIGHT ABDOMENT UPRIGHT CHEST SUPINE ABDOMEN PNEUMOPERITONEUM FREE AIR SENSITIVITY OF IMAGING STUDIES • COMPUTED TOMOGRAPHY • LATERAL UPRIGHT CHEST RADIOGRAPH • AP UPRIGHT CHEST RADIOGRAPH 99% 98% 80 - 90% • LEFT DECUBITUS ABDOMEN RADIOGRAPH 80- 90% • SUPINE ABDOMEN RADIOGRAPH ? PNEUMOPERITONEUM SENSITIVITY OF IMAGING STUDIES • RADIOLOGIC DEMONSTRATION DEPENDS ON: – – – – VOLUME OF FREE AIR TIME INTERVAL BEFORE IMAGING TYPE OF IMAGING CONDUCT OF IMAGING EXAMINATION • AS LITTLE AS ONE CC CAN BE DEMONSTRATED • 10% OF PATIENTS WITH PERFORATED ULCERS DO NOT DEMONSTRATE PNEUMOPERITONEUM UPRIGHT CHEST PERITONITIS THICKENED, ENHANCING PERITONEUM PANCREATIC ABSCESS PANCREATIC GAS • GAS IN PANCREATIC BED – ABSCESS – POST PANCREATIC DRAINAGE PROCEDURE • PERCUTANEOUS OR SURGICAL – PUESTOW PROCEDURE – PSEUDOCYST – PANCREATIC FISTULA PANCREATITIS WITH ABSCESS LESSER SAC ABSCESS GAS IN PANCREATIC ABSCESS PANCREAS-GAS BUT NO ABSCESS POST PUESTOW PROCEDURE PANCREAS-COLON FISTULA LESSER SAC LESSER SAC GASTRIC ULCER PERFORATION INTO LESSER SAC GALLBLADDER IN LESSER SAC GAS IN LESSER SAC PERFORATED GASTRIC ULCER CULTURE HISTORY OF RADIOLOGY INTERMITTENT ABDOMINAL PAIN FOR WEEKS TAKING NSAIDS FOR MONTHS 68-YEAR –OLD MAN SUDDEN ONSET OF SEVERE ABDOMINAL PAIN ... QUESTION PNEUMOTHORAX SIMULATES FREE AIR GAS IN SUBPHRENIC ABSCESS SIMULATES FREE AIR RETROPERITONEAL GAS SIMULATES FREE AIR RETROPERITONEAL GAS RETROPERITONEAL GAS IMAGING • LITTLE CHANGE IN POSITION... OBSTRUCTION ISCHEMIC BOWEL TRAUMA • TRAUMA • PERITONITIS – GAS FORMING ORGANISM PSEUDO-PNEUMOPERITONEUM CENTRAL TENDON GAS YES, BUT JUST THE STOMACH GAS UNDER THE RIGHT HEMIDIAPHRAGM HEPATIC FLEXURE ANTERIOR-SUPERIOR... LIGAMENT GAS BUBBLE OVER LIVER FALCIFORM LIGAMENT PNEUMOPERITONEUM SUBHEPATIC GAS BUBBLE DIVERTICULITIS PNEUMOPERITONEUM ANTERIOR ABDOMINAL WALL ANATOMIC FOLDS FREE AIR INFERIOR EPIGASTRIC VESSELS