GI Flashcards
Where is the A ring in the oesophagus ?
Above the vestibule (muscular)
Where is the B ring in the oesophagus?
Below vestibule, mucosal
Is called a Schatzki ring if narrowed (<13mm)
Barretts
Precursor to Adenocarcinoma 2° to reflux
Shown as high stricture with associated hiatal hernia
Reticular mucosal pattern
Oesophagus Ca buzzwords
Irregular contour
Abrupt/shouldered edges
Squamous oesophageal Ca
Stricture/ulcer/ mass is mid oesophagus
Oesophageal adenocarcinoma
Previous barretts
Stricture/ulcer/mass is in the lower oesophagus
Turcot syndrome
Autosomal recessive
Colonic polyposis and CNS tumours - supratentorial glioblastoma and medulloblastomas
Right sided colitis causes
Shigella
Salmonella
Haemochromatosis mri findings
Low T2
Hepatomegaly
Duodenum
4 parts :
D1 superior
D2 descending
D3 horizontal/transverse
D4 ascending
Ligament of treitz at junction of duodenum and jejenum
Bleed proximal to this is an upper GI bleed.
Signs of bowel ischaemia ( or impending ischaemia )
Engorged mesenteric vessels
Mesenteric oedema
Ascites
Wall thickening
Lack of bowel wall enhancement
Pneumatosis
Indirect inguinal hernia
Lateral to inferior epigastric vessels
Travels with spermatic cord and often into the scrotum
Direct inguinal hernia
Medial to inferior epigastric vessels
Contents do not go into the scrotum
Amyand hernia
Inguinal hernia containing appendix
Littre hernia
Inguinal hernia containing Meckel’s diverticulum
Obturator hernia
Usually In elderly due to weak pelvic floor muscles
Bowel located between pectineus and obturator muscles
Femoral hernia
Posterior and inferior to inguinal ligament.
If contains appendix is called De Gaarengeot hernia
Compresses femoral vein
Aneurysmal dilatation of the small bowel wall with no obstruction
Think lymphoma
Intussusception
Transient small bowel - short segment without wall thickening
Malignant - longer segments with associated thickening and upstream obstruction
Chrons
Affects mouth to anus
Usually terminal ileum
Discontinuous skip lesions
Early changes - aphthous ulcers
Chrons active inflammation
Mural hyperenhancement
Intramural oedema
Mural ulcerations
Chrons stricturing disease
Luminal narrowing with upstream dilatation
Chrons penetrating disease
Sinus tracts, simple fistula,complex fistula, inflammatory mass, abscess
Celiac disease
Reversal of jejunal and ideal fold patterns.
Featureless jejunum due to villous atrophy.
Mesenteric adenopathy
Engorgement of mesenteric vessels
Complication - small bowel t cell lymphoma
Terminal ileum infectious enteritis
Yersinia and TB
Segmental distal small bowel thickening and thickened folds due to infection
Salmonella
Low attenuation mesenteric adenopathy
Whipples disease
Celiac - cavitating mesenteric lymph node syndrome
Radiation enteritis
Mural thickening
Mucosal hyperenhancement and luminal narrowing later on.
Hidebound bowel
In scleroderma
Thin, straight bowel folds stacked together due to replacement of muscular layers with collagen
Most common primary appendiceal neoplasm
Carcinoid
Ischaemic colitis
Splenic flexure most susceptible as it is a watershed area
Segmental thickening
Infectious colitis
Pericolonic stranding
Ascites
Colonic wall thickening
Yersinia and salmonella - right colon
E.coli,cmv and c diff. Cause pancolitis
Accordian sign
Severe Colonic wall thickening and enhancing inner mucosa.can be seen in pseudomembranous colitis
Ulcerative colitis
Begins distally in rectum and spreads proximally.
Increased risk of PSC, cholangiocarcinoma and colon cancer.
Assoc. Sacroiliitis, iritis, erythema nodosum, pyoderma gangrenosum.
Can have backwash ileitis.
Circumferential wall thickening with granular mucosal pattern.
Featureless and foreshortened lead pipe colon.
Toxic mega colon - >6cm, risk of perforation.
Typhlitis
Necrotising inflammatory colitis seen in right colon/ terminal ileum in neutropenic patients.
Stercoral colitis
Focal inflammatory colitis due to increased bowel wall pressure from impacted faeces .
Can lead to bowel wall ischaemia, pressure ulceration and perforation.
FAP
Autosomal dominant
Innumerable pre-malignant polyps.
Prophylactic colectomy
Gardner syndrome is a variant with Desmoid tumours, osteomas, papillary thyroid cancer and epidermoid cysts.
Turcot syndrome is another variant with CNS tumours - glioma and medulloblastoma
Most common tumour involving mesentry
Non-Hodgkin lymphoma
Also causes bulky adenopathy
Peritoneal carcinomatosis
Disseminated Mets to peritoneal surface.
Most commonly caused by mucinous adenocarcinoma
Pseudomyxoma peritonei
Due to mucin producing adenoma or adenocarcinoma of appendix
Also seen in ovarian, gallbladder and pancreatic ca
Necrotising panc imaging
Cg 72-96 hrs after onset of symptoms
Retroperitoneal
Descending and ascending colon
Hyperechoic liver lesion
Mets
Cholangio
Some HCCs
Acute UC presentation
AXR as 1st line
CI to liver biopsy
Echinococcus / hydatid cyst
Abnormal uptake on mibg scan
Pancreas
(Mibg goes into cells metabolically active for adrenaline )
Detect spleen/splenules
RBCs
Zollinger ellison
Multiple gastrinomas
Octreotide scan
Mass obstructing smv that calcifies
Neuroendocrine tumour
Heamachromatosis
In and out of phase reversal of signal
GRE to quantify degree
