EVALUACION DEL COLON POR TC: ENFERMEDADES INFLAMATORIAS

1. EVALUACION DEL COLON POR TC: ENFERMEDADES INFLAMATORIAS

2. COLON NORMAL

3. APENDICITIS • Causa: oclusión de la luz acúmulo de fluido dilatación, inflamación e isquemia eventualmente absceso • TC especificidad y sensibilidad del 98%

4. APENDICITIS • Apendice normal generalmente se lo ve por TC • Presentan gas hasta el 50% • Pueden medir hasta 20 cm

5. APENDICITIS .   Appendicolith. Drawing shows an appendicolith that obstructs the appendiceal lumen, resulting in dilatation of the appendix and wall thickening.

6. Normal appendix. Contrast-enhanced spiral CT scan shows a normal air-filled appendix (arrow).

7. APENDICITIS • TC: diámetro mayor a 6 mm +++ engrosamiento mural + - fluidos o detritus apendicolito 25-40% alteración de la grasa perforación-absceso rara complicación

8. Appendicitis. Contrast-enhanced spiral CT scan shows a dilated, fluid-filled appendix (arrows). Minimal inflammatory changes are also present in the adjacent mesenteric fat.

9. Appendicitis in a patient with acute-onset right lower quadrant pain. Spiral CT scan obtained with oral and intravenous contrast material shows enlargement of the appendix, which is filled with fluid (arrows).

10. .   Appendicitis in a patient with acute-onset right lower quadrant pain. Nonenhanced CT scan shows moderate inflammatory changes in the right lower quadrant. An appendicolith is identified (arrow).

11. Periappendiceal abscess. Contrast-enhanced CT scan shows an inflammatory mass with an air-fluid level in the right lower quadrant (arrow) and associated inflammatory changes in the pericecal fat.

12. APENDAGITIS EPIPLOICA • Isquemia e inflamación causada por torsión o trombosis venosa de un apéndice epiploico • TC: lesión oval de 1-4 cm de la grasa pericólica que rodea el mesenterio

13. Epiploic appendagitis CT scan shows a 2.5-cm-diameter mass (straight arrow) with fat attenuation and mesenteric stranding. The mass is adjacent to the descending colon (curved arrow) and was thought to represent inflammation of the appendix epiploica on the basis of the CT findings.

14. DIVERTICULITIS • Diverticulosis 5-10% en mayores de 45 a 80% en mayores de 85 a • Localización mas común: sigmoides y descendente • Pequeños sacos de 2-3 a 20 mm

16. Diverticulosis. Spiral CT scan obtained with oral and intravenous contrast material shows moderate diverticulosis of the sigmoid colon.

17. DIVERTICULITIS • Engrosamiento segmentario • Hiperhemia • Cambios inflamatorios de la grasa pericólica • DD enf. inflamatorias e isquemia, cáncer colon • La clave de los DD es la presencia de divertículos y su localización (descendente y sigmoides) y la presencia de adenomegalias

18. DIVERTICULITIS • Complicaciones: absceso diverticular fístula colovesical perforación

19. .   Diverticulitis wall thickening in the sigmoid colon (arrows) with adjacent inflammatory changes in the pericolic fat.

20. Diverticular abscess. moderate wall thickening in the sigmoid colon (S) with significant adjacent inflammatory changes and stranding of the pericolic fat. A 3-cm-diameter fluid collection (*) is seen between the sigmoid colon and bladder (B), a finding compatible with a diverticular abscess.

21. .   Colovesical fistula. moderate wall thickening in the sigmoid colon (S) with adjacent inflammatory changes and stranding of the pericolic fat. Focal wall thickening is seen in the left posterior part of the bladder adjacent to the inflamed sigmoid (arrow). A moderate amount of air is also present in the bladder, a finding compatible with a colovesical fistula.

22. TIFLITIS • Enterocolitis neutropénica • Más frec. en pac. con QMT x LMA. • También en anemia, linfoma, SIDA, tx renal • TC: inflamación del ciego, colon ascendente e ileo terminal • Complicaciones: necrosis, perforación (neumatosis, neumoperitoneo)

23. Typhlitis. Drawing shows the significant wall thickening that involves the cecum in patients with typhlitis.

24. Typhlitis in a patient with LMA inflammation and marked thickening of the cecum (arrowheads), findings compatible with typhlitis. Minimal pericecal inflammation is present in the adjacent mesenteric fat. The descending colon (D) appears normal

25. COLITIS POR RADIACION • Radiación aguda: diarrea autolimitada TC no especifica engrosamiento mural locorregional • Radiación crónica: 6-24 meses post RDT TC engrosamiento mural inespecífico en recto, alteración de la grasa, fibrosis perirrectal Complicación: fístula y estricturas

26. Radiation fibrosis. Drawing shows smooth wall thickening and fibrosis in the sigmoid colon, which narrow the colonic lumen.

27. Radiation proctitis in a 38-year-old woman who underwent radiation therapy for cervical cancer. marked thickening of the cervix and vagina (curved arrow) with necrosis (open arrow), findings compatible with known locally invasive cervical cancer. Marked thickening of the rectum due to radiation colitis is also present (solid straight arrows).

28. ENFERMEDAD INFLAMATORIA INTESTINAL • La afectación del colon derecho e ID es típica de Crohn aunque puede afectar al izquierdo • Al contrario la C ulcerosa afecta es típica del colon izquierdo o difusa y raramente afecta solamente el colon derecho

29. ENFERMEDAD INFLAMATORIA INTESTINAL • TC: ambos presentan engrosamiento mural (Crohn hasta 11-13 mm, C. ulcerosa hasta 7-8 mm) • C ulcerosa es difusa y simétrica • Crohn excéntrica y segmentaria con áreas respetadas

30. ENFERMEDAD INFLAMATORIA INTESTINAL • El signo del halo de baja atenuación (deposito de grasa submucosa) es más común en la C ulcerosa que en Crohn • Proliferación de la grasa mesentérica es casi exclusiva del Crohn • Adenomegalias son mas comunes en Crohn • Complicaciones: abscesos-Crohn fistulas:enterovesicales, esterocutaneas, perianales, rectovaginales

31. Crohn disease. CT scan obtained with oral contrast material shows moderate thickening of the terminal ileum (curved arrow) and cecum (straight arrow) with adjacent inflammatory changes in the pericolic fat.

32. Ulcerative colitis in a 27-year-old man. Contrast-enhanced CT scan shows minimal diffuse thickening of the sigmoid colon with minimal inflammatory stranding. The remainder of the colon was normal (not shown).

33. Crohn disease. CT scan obtained with oral contrast material shows low-attenuation submucosal fat in the ascending colon (arrow) and fibrofatty proliferation of adjacent mesenteric fat (*).

34. Ulcerative colitis. CT scan of a patient with long-standing ulcerative colitis shows a submucosal halo of fat within the rectum (arrow). There is also perirectal fibrofatty proliferation (*).

35. Crohn disease. CT scan obtained with oral and intravenous contrast material shows an abscess involving the iliacus muscle (black arrow) with a fistula to the anterior abdominal wall (white arrow).

36. COLITIS ISQUEMICA • Causa común de dolor abdominal en ancianos • Causas: oclusión mesentérica vascular arterial o venosa, embólica, trombótica o invasiva tumoral • Segmentaria o difusa • El angulo esplénico y el rectosigma son más suceptibles de isquemia

37. COLITIS ISQUEMICA • Típicamente engrosamiento mural extenso • Signo del doble halo • TC muestra claramente el trombo en los casos de isquemia oclusiva o por invasión tumoral • Neumatosis con o sin gas dentro de los vasos mesentéricos y portales es un signo ominoso sugestivo de necrosis e isquemia

38. Diffuse ischemic colitis. CT scan obtained with oral and intravenous contrast material shows diffuse, low-attenuation thickening of the colonic wall (arrows). This is an example of the halo sign.

39. Segmental ischemic colitis. CT scan obtained with oral and intravenous contrast material shows focal thickening of two colonic loops in the left abdomen (arrows).

40. Ischemic colitis in a 65-year-old man with abdominal pain after surgery for pancreatic cancer. Contrast-enhanced spiral CT scans show marked edema and thickening of the small bowel (SB) and colon (C) to the level of the splenic flexure, findings compatible with ischemia due to thrombus in the superior mesenteric vein (arrow in a). There is also moderate atherosclerosis of the aorta and ascites.

41. .   Ischemic colitis. Drawing shows ischemia and pneumatosis involving a segment of colon.

42. .   Ischemic colitis in a critically ill patient. CT scan obtained with oral and intravenous contrast material shows pneumatosis involving the ascending colon and transverse colon (arrows), findings compatible with ischemia and infarction.

43. COLITIS INFECCIOSA • Bacterias: shigella, salmonella, yersinia, campilobacter, staphylococcus y trachomatis • Fúngicas: histoplasmosis, mucormicosis y actinomices • Virus: herpes, citomega, y rotavirus • Amebiasis y TBC • TC engrosamiento mural, con realce homogeneo

44. Infectious colitis from Escherichia coli in a 52-year-old man with abdominal pain and severe bloody diarrhea. CT scan obtained with oral and intravenous contrast material shows moderate thickening of the colon (arrows) and inflammatory changes in the mesenteric fat. E coli was cultured from stool.

45. COLITIS SEUDOMEMBRANOSA • Resultado del crecimiento excesivo del Clostridium Difficile • Caracterizado por seudomembranas (exudado de c. necróticas que desnudan la mucosa) • Clásicamente dan pancolitis • TC: engrosamiento circunferencial y excéntrico de la pared mas irregular que en el Crohn • Engrosamiento de austras (casos severos), signo del acordeón

46. Pseudomembranous colitis. Drawing shows marked colonic wall thickening and mucosal plaques.

47. Pseudomembranous colitis. Spiral CT scan obtained with oral and intravenous contrast material shows marked wall thickening throughout the colon (thickness, 15 mm) and pericolic inflammation. The thickening in the transverse colon is asymmetric.

48. Pseudomembranous colitis. Spiral CT scan obtained with oral and intravenous contrast material shows marked wall thickening throughout the colon. The wall is of low attenuation, which is compatible with edema or inflammation, and there is significant enhancement of the mucosa due to hyperemia. There is also moderate pericolic inflammation and ascites.

49. .   Accordion sign in a patient with pseudomembranous colitis. Spiral CT scan obtained with oral contrast material shows marked wall thickening throughout the colon. The colonic wall is so thick that only minimal contrast material can be seen sandwiched between the thick walls, creating the appearance of an accordion. There is also pericolic inflammation and ascites.

50. Pseudomembranous colitis in a patient with severe diarrhea. Spiral CT scan obtained with oral contrast material shows rectal thickening (arrows) and perirectal inflammation. The remainder of the colon was normal (not shown). Pseudomembranous colitis was diagnosed at endoscopy.