GI Tract Pathology - DMS 152 (PDF)

GI tract Pathology DMS 152 Duplication Cyst Duplication cysts are embryologic mistakes. Cab ne seen in stomach or bowels Asymptomatic or With symptoms, depending on their size, location. Criteria for a duplication cyst: Is lined with epithelium Has a well...

GI tract Pathology DMS 152 Duplication Cyst Duplication cysts are embryologic mistakes. Cab ne seen in stomach or bowels Asymptomatic or With symptoms, depending on their size, location. Criteria for a duplication cyst: Is lined with epithelium Has a well-developed muscular wall Is contiguous with the stomach or bowel Duplication Cyst Is usually found on the greater curvature of the stomach. May come from the pancreas or duodenum. Clinical symptoms: High intestinal obstruction distention Vomiting Abdominal pain Hemorrhage and fistula formation may also occur Duplication Cyst Sono Well defined Round Fluid-filled mass Anechoic Acoustic enhancement Hypoechoic outer muscular rim and a hyperechoic inner rim of mucosa. Duplication Cyst On U/S, duplication cysts appear anechoic with a thin inner echogenic rim (mucosa) and a wider outer hypoechoic rim (muscle layer) CT contrast image of the gastric duplication cyst. Gastric Bezoar Gastric bezoar Intragastric movable mass of accumulated ingested material Divided into three categories: Trichobezoars - hair balls in young women Phytobezoars - vegetable matter (e.g., unripe persimmons) Concretions - inorganic materials (e.g., sand, asphalt, and shellac) S/S N &V pain Gastric Bezoar Sono hyperechoic curvilinear dense strip/band at the anterior margin. Radiography or CT is the mobile imaging modality of choice can look complex Benign Tumors: Polyp A polyp small, tumorlike growth that projects from a mucous membrane. Gastric polyp an outgrowth of tissue from the gastric wall. S/S asymptomatic when the polyp is small. ss the polyp grows – abdominal pain Sono Solid mass attached to gastric wall can be seen with Endoscopic view of a fluid distention of stomach polyp in the gastrointestinal tract Large ones – inhomogeneous A pedicle may be seen Benign Tumors: Leiomyoma m/c tumor of the stomach. seen as a mass similar to carcinoma usually small and asymptomatic. Sono Solid mass Hypoechoic Trv image of LUQ: If necrosis – cystic areas a complex tumor in the Mass is continuous with muscle layer region of the stomach was diagnosed as leiomyoma. Malignant Tumors: Gastric Carcinoma Carcinoma m/c cancer of the stomach. 5th leading cause of death occurs more often in older men 50% of tumors occur in the pylorus Lesions may be ulcerated, diffuse, polypoid, or superficial. Gastric Carcinoma Sono Target sign Pseudokidney sign Gastric wall thickening Mass is polypoid Lobulated Fungating (cauliflower like) May cause obstruction of gastric ouitlet Malignant Tumors Lymphoma Leiomyosarcoma Can occur as a primary tumor of aka gastric sarcoma GI tract Occurs in older people Disseminated lymphoma Mass is generally globular or occurs as a multifocal lesion in the irregular. GI tract Hypoechoic Hypoechoic lesions seen May become huge, outstripping its blood supply, with central necrosis leading to cystic degeneration and cavitation. Malignant Tumors: Lymphoma Gastric Lymphoma. The stomach has enlarged and thickened mucosal folds, multiple submucosal nodules, ulceration. Malignant Tumors: Metastatic disease Mets to the stomach are rare. May come from a melanoma or from lung or breast cancer. Tumors are found in the submucosal layer, forming Sono circumscribed nodules or A target pattern plaques. Wall thickening without layering is visible. Lower GI Tract Obstruction and dilation A small bowel obstruction is associated with dilation of the bowel loops proximal to the site of the obstruction. Obstruction can happen due to Gallstone accumulation Tumors Small bowel adenocarcinoma Congenital atresia and stenosis Annular pancreas Small bowel obstruction Img: Duodenal atresia – narrowing at duodenum (arrows) Sono of Bowel obstruction: hyperactive, dilated bowel loops bowel wall thickening in some cases duoden. & stomach seen as large anechoic structures Small Bowel Obstruction prominent dilated loops of bowel Acute Appendicitis Acute appendicitis is the result The appendix obstructed by: of luminal obstruction and Fecal material inflammation Foreign body leading to ischemia of the Carcinoma of the cecum vermiform appendix. Stenosis This ischemia produces necrosis, Inflammation that leads to complications: Kinking of the organ Perforation Lymphatic hypertrophy Periappendicular abscess resulting from systemic infection Peritonitis Acute Appendicitis Normal Abnormal appendix Acute Appendicitis S/S Pain and rebound tenderness over RLQ (McBurney’s sign). Abdominal rigidity TRIAD: 1. RLQ pain N &V 2. Leukocytosis Diarrhea 3. Fever Leukocytosis Fever Acute appendicitis can occur at any age but is more prevalent at younger ages. Acute Appendicitis The rate of perforation in the preschool child can be as high as 70% compared with the overall figure of 30% for children and 21% to 22% for adults. Acute Appendicitis App vid Sono Complications Progression of acute appendicitis to frank Tubular noncompressible structure perforation is more rapid in the younger with a target appearance of an outer child, sometimes within 6 to 12 hours. hypoechoc muscular layer and Perforation occurs in 80-100% of children under the age of 3. echogenic submucosa layer surrounded by a fluid-filled centre Perforated appendix appears as a fluid-filled collection that can lead to Abscess formation Appendix > 6mm AP complex mass Peritonitis Appendicolith may be noted Fluid with debris fecaliths Thick adjacent abdo wall Enlarged mesenteric lymph nodes Women ages 20 to 40 years are at high Inflamed fat and free fluid risk of having misdiagnosis on initial physical exam. Acute Appendicitis Ultrasound – primary method Differential diagnoses : of imaging Acute gastroenteritis Graded compression Mesenteric lymphadenitis in children to displace the bowel gas Ruptured ectopic pregnancy to demonstrate compressibility of the appendix Mittelschmerz Inflammation of Meckel The appendix is visualized near diverticulum the cecum and terminal ileum Right ovarian torsion Doppler  Appendicitis A. A normal thin-walled appendix seen just anterior to the iliac vessels B. Images with and without compression show no change in the size of the dilated appendix. Fluid is seen when the compression is released C. Sag and trv (D) images of the inflamed appendix demonstrate peripheral hyperemia of the wall E. A dilated blind-ended tubular structure = 0.93 cm represents an inflamed appendix F. Dilated fluid-filled appendix in RLQ  Appendicitis G. A large echogenic appendicolith (between calipers) within an irregular dilated appendix H. Echogenic appendicolith (arrows) is seen within the appendix (A). Note the acoustic shadowing I. Enlarged LNs (arrows) are seen anterior to an inflamed appendix (A) J. A complex mass (A) seen in RLQ represents an abscess in a patient with a ruptured appendix. Acute Appendicitis Acute Appendicitis Appendicolith Appendicolith seen as intraluminal foci of high-amplitude echoes with acoustic shadowing. Mucocele Mucocele Classified into three groups: is distension of appendix by mucus Hyperplasia Focal or diffuse RLQ pain resembling Mucinous cystadenoma appendicitis is m/c symptom Mucinous cystadenocarcinoma Patients may be asymptomatic has malignant potential Rare A mucocele rupture can cause massive accumulation of gelatinous ascites aka pseudomyxoma peritonei Mucolocele Sono cystic or complex mass up to 7 cm in diameter with through transmission located in RLQ Diff dx ovarian cysts mesenteric or omental cysts duplication cysts renal cysts or even abdominal abscess Meckel Diverticulitis Diverticulum Pouchlike herniation through the muscular wall of a tubular organ: Colon – m/c Stomach S/S Small intestine intestinal obstruction Meckel diverticulum rectal bleeding Located on the antemesenteric diverticular inflammation border of the distal ileum, approximately 2 feet from the ileocecal valve Meckel diverticulitis mimics 3-6 cm long acute appendicitis Present in 2% of the population. Meckel Diverticulitis Sono the wall of Meckel’s diverticulum consists of mucosal, muscular, and serosal layers Noncompressibility of the obstructed, inflamed diverticulum indicates that intraluminal fluid is trapped Crohn’s Disease IBD autoimmune regional enteritis inflammatory disease that affects any part of GI tract, but m/c: terminal ileum colon The reaction involves the entire thickness of the bowel wall. S/S Diarrhea Fever RLQ pain Crohn’s Disease Sono (use graded compression) Symmetrically thickened hypoechoic bowel walls Non- or partially compressible Bull’s eye or target sign on trv Pseudo kidney – in sag ↑ vascularity Secondary appendicitis Lymphadenopathy Crohn’s Disease Prominent colon with increased vascularity Tumors of the Colon: Lymphoma A tumor that usually occurs late in life in 60s Also occur in young children S/S Intestinal blood loss Weight loss Anorexia Abdominal pain. The patient may have an intestinal obstruction or palpable mass. Tumors of the Colon: Lymphoma Sono large, discrete mass with a target pattern or small anechoic mass representing subserosal nodes mesenteric nodal involvement (LNs) bowel may show pseudokidney sign or hydronephrotic pseudokidney sign Tumors of the Colon: Lymphoma Lymphoma of the sigmoid colon seen with wall thickening in the CT and ultrasound images. Tumors of the Colon: Leiomyosarcoma Rare Smooth muscle tumor Malignant Occur in duodenum, jejunum and ileum Patients are in their 50-60s