LOOKING FOR AIR IN ALL THE WRONG PLACES Richard M. Gore, MD North Shore University Health System University of Chicago Evanston, IL

Transcription

1 SIGNIFICANCE OF EXTRALUMINAL ABDOMINAL GAS: LOOKING FOR AIR IN ALL THE WRONG PLACES Richard M. Gore, MD North Shore University Health System University of Chicago Evanston, IL SCBT/MR 2012 October 26, :00-3:10

2 NO DISCLOSURES

3 TOPICS PNEUMOPERITONEUM PNEUMORETROPERITONEUM PNEUMATOSIS INTESTINALIS PORTAL-MESENTERIC VENOUS GAS PNEUMOBILIA

4 PNEUMOPERITONEUM

5 THE SPECTRUM OF PNEUMOPERITONEUM Expected and benign finding requiring no treatment Sensitive indicator of sudden and lifethreatening perforation of the GI tract

6 PNEUMOPERITONEUM: BENIGN CAUSES Surgery Surgery Percutaneous Endoscopic Gastrostomy Percutaneous Peritoneal dialysis Endoscopic Gastrostomy Peritoneal Biopsy dialysis Biopsy Percutaneous abscess drainage Percutaneous Pneumothorax abscess drainage Pneumomediastinum

7 PNEUMOPERITONEUM: LIFE-THREATENING Perforation of benign ulcer Diverticulitis Appendicitis Perforation of neoplasm Pneumatosis Bowel obstruction

8 PNEUMOPERITONEUM: LIFE-THREATENING Intestinal ischemia and infarction Toxic megacolon Necrotizing enterocolitis Inflammatory bowel disease Typhlitis Pseudomembranous colitis

9 PNEUMOPERITONEUM: LIFE-THREATENING Anastomotic leak Upper GI endoscopy Colonoscopy

10 RIGLER S SIGN

11 LIVER EDGE SIGN

12 FALCIFORM LIGAMENT SIGN

13 BENIGN CAUSES OF PNEUMOPERITONEUM

14 POSTOPERATIVE PERITONEAL DIALYSIS PERCUTANEOUS GASTROSTOMY

15 POSTOPERATIVE PNEUMOPERITONEUM POSTOPERATIVE PNEUMOPERITONEUM

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19 POSTOPERATIVE (OPEN) PNEUMOPERITONEUM ON UPRIGHT CXR POD # % POD # % POD # % Tang Dis Colon Rectum 43: , 2000

20 FACTORS INFLUENCING DURATION OF POST OPERATIVE PNEUMOPERITONEUM Obesity: prevalence of PP is less in fat compared to thin patients Gender: PP more prevalent in men Drains: greater incidence of PP No effect: age, surgery duration, presence and location of anastomosis, time to flatus, time to first bowel movement

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22 PP IN THE ERA OF LAPAROSCOPIC SURGERY Iatrogenic GI tract perforations due to trocar insertion and thermal injury: 0.06%- 0.4% Artificial pneumoperitoneum Small incisions minimize room air

23 PP IN THE ERA OF LAPAROSCOPIC SURGERY Iatrogenic GI tract perforations due to trocar insertion and thermal injury: 0.06%- 0.4% Artificial pneumoperitoneum Small incisions minimize room air

24 PP IN OPEN vs LAPAROSCOPIC CHOLECYSTECTOMY ON CXR-24 hrs Open cholecystectomy: 60%, minimal to moderate 2:1 Laparoscopic cholecystectomy: 24%, minimal to moderate 5:1 Gayer Semin Ultrasound, CT, MR 25: , 2004

25 PP: CT vs RADIOGRAPH 3 days postoperative: 87% on CT, 53% on plain radiograph 6 days postoperative: 50% on CT, 8% on plain radiograph Earls AJR 161: , 1993

26 IN PATIENTS WITH COMPLICATIONS The amount of free air should be decreasing Any increase is very worrisome Difficult to exactly compare quantity of gas on CT study with radiograph

27 PERITONEAL DIALYSIS

28 PERITONEAL DIALYSIS Seen in 30% of patients on PD The presence, quantity, and distribution of free air is not helpful in separating perforations from nonperforations Lee JCAT 18: , 1994

29 PERCUTANEOUS ENDOSCOPIC GASTROSTOMY

30 PNEUMOPERITONEUM S/P PEG TUBE INSERTIONS 8.6%-55.6% Free air on CXR 1 to 3 days Free air on CT 1 to 9 days In the absence of clinical symptoms is of no clinical significance and does not need further evaluation

31 LIFE- THREATENING CAUSES OF PNEUMOPERITONEUM

32 GI TRACT PERFORATION

33 PERFORATION Emergent condition that requires prompt surgery Spontaneous, traumatic, or iatrogenic causes Variable clinical presentations, particularly in the early clinical course

34 GI TRACT PERFORATION Concentration of air bubbles next to gut Supramesocolic vs inframesocolic space Preponderance of abdominal vs pelvic gas Perivisceral fat stranding Segmental bowel wall thickening Abscess Extraluminal fluid Focal defect in bowel wall

35 GI TRACT PERFORATION Extraluminal contrast Focal defect in bowel wall Segmental bowel wall thickening Abscess-fluid

36 GI TRACT PERFORATION Extraluminal contrast Focal defect in bowel wall Segmental bowel wall thickening Abscess-fluid

37 GI TRACT PERFORATION Extraluminal contrast Focal defect in bowel wall Segmental bowel wall thickening Abscess-fluid

38 GI TRACT PERFORATION Extraluminal contrast Focal defect in bowel wall Segmental bowel wall thickening Abscess-fluid

39 GI TRACT PERFORATION Extraluminal contrast Focal defect in bowel wall Segmental bowel wall thickening Abscess-fluid

40 GI TRACT PERFORATION Extraluminal contrast Focal defect in bowel wall Segmental bowel wall thickening Abscess-fluid

41 GI TRACT PERFORATION Extraluminal contrast Focal defect in bowel wall Segmental bowel wall thickening Abscess-fluid

42 GI TRACT PERFORATION Concentration of air bubbles next to gut Supramesocolic vs inframesocolic space Preponderance of abdominal vs pelvic gas Perivisceral fat stranding

43 GI TRACT PERFORATION Concentration of air bubbles next to gut Supramesocolic vs inframesocolic space Preponderance of abdominal vs pelvic gas Perivisceral fat stranding

44 GI TRACT PERFORATION Concentration of air bubbles next to gut Supramesocolic vs inframesocolic space Preponderance of abdominal vs pelvic gas Perivisceral fat stranding

45 GI TRACT PERFORATION Concentration of air bubbles next to gut Supramesocolic vs inframesocolic space Preponderance of abdominal vs pelvic gas Perivisceral fat stranding

46 GI TRACT PERFORATION Concentration of air bubbles next to gut Supramesocolic vs inframesocolic space Preponderance of abdominal vs pelvic gas Perivisceral fat stranding

47 FISSURE LIGAMENTUM VENOSUM- FALCIFORM LIGAMENT

48 CT FEATURES OF PNEUMOPERITONEUM PROXIMAL GI PERFORATION FALCIFORM LIG 60% 0% DISTAL GI POCKETS OF AIR 10% 69% WALL THICKENING 50% 100% ABSCESS 20% 53% ASCITES 90% 63% FAT STRANDING 30% 72% Yeung J Clin Imaging 28: , 2004 PERFORATION

49 GI TRACT PERFORATION: LOCATION OF GAS BUBBLES IN 86 PATIENTS Stomach and liver Inframesocolic Infra- and supramesocolic Gastroduodenal perforation Small bowel perforation Colon perforation Hainaux AJR 187: , 2006

50 CT FEATURES OF PNEUMOPERITONEUM (n=53) UPPER GI PERFORATION LOWER GI PERFORATION PERIPORTAL FREE AIR FALCIFORM LIGAMENT LIGAMENTUM TERES Cho HS Eur J Radiology 2007

51 GASTRODUODENAL PERFORATIONS Peptic ulcer disease Necrotic or ulcerated malignancies Large amount of extraluminal air Air in lesser sac, ligamentum teres, ligamentum venosum Ulceration, focal interruption of wall, abrupt wall thickening with adjacent increased fat density

52 GASTRODUODENAL PERFORATIONS Traumatic injures involve 2 nd and 3 rd portions of the duodenum Blunt trauma in children and penetrating trauma in adults Cause pneumoretroperitoneum in the anterior pararenal space

53 GASTRODUODENAL PERFORATIONS DUODENAL 38.3% JUXTA-PYLORIC 35.6% GASTRIC 19.1% PYLORIC 6.8% Grassi Eur J Radiology 50: 30-36, 2004

54 PEPTIC ULCER DISEASE

55 DIVERTICULITIS

56 PERFORATED NSAID ULCER

57 PERFORATED ANTRAL ULCER

58 PEPTIC ULCER DISEASE

59 SUPERIOR RECESS LESSER SAC

60 SMALL BOWEL PERFORATIONS Diverticulitis Ischemic or bacterial enteritis Crohn s disease Ingested foreign bodies Bowel obstruction Volvulus Intussusception

61 SMALL BOWEL PERFORATIONS Abdominal trauma Iatrogenic injury Postoperative perforation Anastomotic leakage Amount of extraluminal air is small or absent in most cases unlike UGI perf Extraluminal air seen in only 50% of CTs

62 SMALL BOWEL PERFORATIONS Findings often subtle- search for gas trapped in mesenteric folds Postoperative perforation and anastomotic leakage usually occur within first week of surgery Suggest perforation or leak with persistent or progressively increasing free air

63 PERFORATED ILEUM BY CHICKEN BONE

64 PERFORATED ILEUM BY CHICKEN BONE

65 SMALL BOWEL PERFORATION

66 COLONIC PERFORATION Malignant neoplasm Diverticulitis Spontaneous perforation Trauma Ischemia

67 COLONIC PERFORATION Free air on plain radiograph 33% Free air on MDCT 100% Dirty fat sign 100% Wall thickening at perf site 100% Extraluminal fluid 100% Dirty mass 83% Interruption of colon wall 67% Miki JCAT 31: , 2007

68 COLONIC PERFORATION: LEFT SIDED Malignant neoplasm Diverticulitis Spontaneous perforation Blunt trauma Ischemia

69 COLONIC PERFORATION: RIGHT SIDED Inflammatory lesions Penetrating trauma Cecum- LBO, toxic megacolon, ileus

70 DIVERTICULITIS

71 DIVERTICULITIS

72 ANASTOMOTIC LEAKS Leak rate 3.6% to 9% 30% may have clinically occult leaks High risk: low rectal anastomosis and Whipple s procedure

73 ANASTOMOTIC LEAKS Peri-anastomic fluid and gas are the best indicators of anastomotic leaks

74 A A A

75 PNEUMORETROPERITONEUM

76 PNEUMORETROPERITONEUM Postoperative Postdiagnostic procedure (ERCP) Penetrating trauma Blunt traumatic rupture of duodenum Pelvic trauma with rectal perforation

77 PNEUMORETROPERITONEUM Spontaneous colonic perforation volvulus, obstruction, carcinoma, diverticulitis Extension from pneumomediastinum Gas-containing retroperitoneal abscess

78 PERFORATION DURING ERCP

79 PERFORATION FROM COLONOSCOPY

80 OCCULT COLONIC PERFORATION WITH INCOMPLETE COLONOSCOPY Optical colonoscopy perforation rate is 1/3,115 (.032%) to 1/510 (0.196%) 2/262 (0.8%) had occult perforation Recommend low dose CT before rectal tube insertion and gas insufflation in all patients with same day or next day CTC Hough AJR 191: , 2008

81 ACCURACY OF MDCT IN DETECTING PERFORATION SITE OF GI TRACT Axial images only: 87.8% Axial + MPR images: 93.9% Kim JW Abdominal Imaging 36: , 2011 (Oct)

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