imaging of the abdomen & the gastrointestinal

IMAGING OF THE IMAGING OF THE ABDOMEN & THE GITABDOMEN & THE GITYEAR 4, MBBSYEAR 4, MBBS

Dr Azlin bt Sa’at @ YusofDr Azlin bt Sa’at @ Yusof

Kulliyah of MedicineKulliyah of Medicine

IIUM.IIUM.

CONTENTSCONTENTS Imaging modalities:Imaging modalities:

Plain XR Plain XR Contrast studiesContrast studies UltrasoundUltrasound Computed TomographyComputed Tomography Magnetic Resonance ImagingMagnetic Resonance Imaging Angiogram and interventionalAngiogram and interventional Others: ERCP, Others: ERCP,

PTC, intra-op & T-tube cholangiogram,PTC, intra-op & T-tube cholangiogram, Radionuclide imaging – IDA, Meckel’s Radionuclide imaging – IDA, Meckel’s

and GIT and GIT

bleed.bleed. Quiz and summaryQuiz and summary..

PLAIN ABD XRAYPLAIN ABD XRAY

(1) Radiographic anatomy(1) Radiographic anatomy- know where solid organs lie:

* intraperitoneal* retroperitoneal – kidneys, adrenals, pancreas, psoas,

IVC, Ao, lymph node.* pro-peritoneal fat* GIT

(2) Interpretation(2) Interpretation- quality- views: supine, erect, decubitus (usu lt side down)- bowel gas pattern:

* normal gas : stomach and colon* normal air-fluid level : stomach and proximal duodenum* stomach – rugae; jejunum – feathery; small bowel – valvulae conniventes; colon – haustrations.

PLAIN ABD XRAY (1)PLAIN ABD XRAY (1)

* Dilated? - jejunum > 3.5 cm- mid small bowel > 3 cm- ileum > 2.5 cm- tranverse colon > 5.5 cm- caecum > 8 cm

- Psoas outline: symmetrical and slightly concave lateral borders.- Renal outline : 10-12cm / 3.5 vertebral height.- Bladder outline.- Liver and splenic outline.- Intraperitoneal fluid / collections.- Calculi / calcifications : GB, kidneys, pancreas, lymph

nodes, vacsular, phleboliths, tumoral.

- Soft tissue masses.- Extra-luminal gasses.


(3) Various conditions(3) Various conditions

* Bowel obstruction:* Bowel obstruction:

Mechanical obstruction of the small bowel:- small bowel dilatation with normal / reduced calibre of

colon.

Large bowel obstruction:- dilatation of large bowel +/- small bowel dilatation.

Paralytic ileus:- large + small bowel dilatation +/- gas in sigmoid to rectum.

Local peritonitis:- dilatation of loops adjacent to inflammatory process

‘sentinel loops’



* Bowel obstruction (cont.):* Bowel obstruction (cont.):

Gasteroenteritis:- normal / excess fluid levels / ~ paralytic ileus / ~small bowel obstruction.

Small bowel infarction:- obs of small or large bowel

Closed loop obstruction:- caecal/sigmoid volvulus – filled with air + char shape. obstructed hernias – fluid-filled, usu not visible.

Toxic dilatation of the colon:- maximal dilatation usu at transverse colon, lost/abnormal haustra +/- polypoid shadows.

SUPINE ERECT

Small bowel obstructionSmall bowel obstruction


Large bowel Large bowel obstructionobstruction

Small + large bowelSmall + large bowel

Toxic dilatation due Toxic dilatation due to ulcerative colitisto ulcerative colitis


VOLVULUSVOLVULUS

(3) Various conditions(3) Various conditions

* Extra-luminal gas:* Extra-luminal gas:

- Free intraperitoneal gas:- Free intraperitoneal gas:

* causes – post-laparotomy (up to 7 days)* causes – post-laparotomy (up to 7 days)

- perforated peptic ulcer- perforated peptic ulcer

- IBD / infarction- IBD / infarction

* * ERECT FILM!ERECT FILM! – air under diaphragm or lateral decubitus – air under diaphragm or lateral decubitus

* supine – gas outlining the falciform lig.* supine – gas outlining the falciform lig.

- gas on both sides of the bowel (Rigler’s sign)- gas on both sides of the bowel (Rigler’s sign)


PLAIN CXRPLAIN CXR

Air under hemidiaphragm

Free intraperitoneal air

PLAIN ABD XRAY PLAIN ABD XRAY

* Extra-luminal gas (cont.)* Extra-luminal gas (cont.)

- Intramural gas pattern:- Intramural gas pattern:

* spherical – pneumatosis coli* spherical – pneumatosis coli

* linear – infarction* linear – infarction

* neonatal period – NEC* neonatal period – NEC


NEC PNEUMATOSIS COLI

* Extra-luminal gas (cont.)* Extra-luminal gas (cont.)

- Gas elsewhere:- Gas elsewhere:

* biliary system – following sphincterotomy / fistula (stone) / * biliary system – following sphincterotomy / fistula (stone) / duodenal ulceration.duodenal ulceration.

* GB * kidneys* GB * kidneys *abscess *abscess *subphrenic*subphrenic


KidneysBiliary treeGalbladder

Subphrenic

????

PLAIN ABD XRAY PLAIN ABD XRAY

*Ascites*Ascites *Calcifications*Calcifications

- phleboliths - vascular

- solid organs: liver, spleen, pancreas, adrenals, kidneys.

- tumours: fibroids, ovarian masses.

- soft tissue

- faecoliths.

PLAIN ABD XRAY (8) PLAIN ABD XRAY (8)

Pancreatic

Gallstones

Appendicolith

Uterine fibroid

* Abdominal / pelvic masses* Abdominal / pelvic masses


CONTRAST STUDIESCONTRAST STUDIES

(1) General(1) General

* Contrast material: * Contrast material:

- BARIUM vs GASTROGRAFFIN vs LOCM- BARIUM vs GASTROGRAFFIN vs LOCM

* Single contrast vs Double contrast* Single contrast vs Double contrast

Good opacification Good opacification and coating BUT and coating BUT peritoneal leak peritoneal leak peritonitis peritonitis

Safe if ?peritoneal Safe if ?peritoneal leak BUT hypertonic, leak BUT hypertonic, lung irritant if lung irritant if aspirated and less aspirated and less opaqueopaque

Safe if aspirated or Safe if aspirated or leak BUT expensive leak BUT expensive and poor and poor opacification and opacification and coatingcoating

Oesophagus, small bowel Oesophagus, small bowel and TRO Hirschprungs and and TRO Hirschprungs and obstruction only. (no need obstruction only. (no need bowel prep)bowel prep)

Ideal for stomach, and Ideal for stomach, and colon. Excellent mucosal colon. Excellent mucosal detail.detail.

* Basic terms:* Basic terms:

- wall of the bowel -> not seen.- wall of the bowel -> not seen.

- mucosal folds: contracted -> folded- mucosal folds: contracted -> folded

distended -> valv conniventes / haustradistended -> valv conniventes / haustra

abnormal -> ? smoothing / ? Irregularabnormal -> ? smoothing / ? Irregular

- filling defect:- filling defect:

Intra-luminal Intra-mural Extra-luminal

CONTRAST STUDIES (1)CONTRAST STUDIES (1)

Tapering ends vs. overhanging Tapering ends vs. overhanging edges (shouldering)edges (shouldering)

- Ulceration: - Ulceration:

- Stricture: persistent narrowing- Stricture: persistent narrowing

In profileIn profile En faceEn face


Description: Description: - site of the abnormality- site of the abnormality- what is its shape? - what is its shape? - how long?- how long?- is there a soft tissue mass?- is there a soft tissue mass?


(2) Barium swallow(2) Barium swallow

* Barium swallow vs OGDS* Barium swallow vs OGDS

* Method:* Method: - CONTROL FILM !!!! - CONTROL FILM !!!! - swallow while flouro,- swallow while flouro, - oblique position, - oblique position, - films taken in full, collapsed +/- air-filled state.- films taken in full, collapsed +/- air-filled state.

* Normal:* Normal: full full smooth outline smooth outline collapsed collapsed 3-4 long straight parallel lines 3-4 long straight parallel lines indentation indentation left: aorta and left bronchus left: aorta and left bronchus

anterior: (L) atrium and ventricleanterior: (L) atrium and ventricle peristalsis peristalsis smooth smooth

elderly: pronounced and elderly: pronounced and prolonged (3o contractions)prolonged (3o contractions)


Full Collapsed 3o contractions

CONTRAST STUDIES (5) – Barium SwallowCONTRAST STUDIES (5) – Barium Swallow

* * Pathology:Pathology: - Carcinoma - Carcinoma

(a) (b)


Benign peptic strictureBenign peptic stricture AchalasiaAchalasia

CandidiasisCandidiasis


Oesophageal webOesophageal web


LeiomyomaLeiomyoma

VaricesVarices

Ca bronchusCa bronchus

(3) Barium meal(3) Barium meal

* Method: * Method: - swallow barium then gas-producing - swallow barium then gas-producing agent, agent,

- iv smooth muscle relaxant.- iv smooth muscle relaxant.

- various positions.- various positions.

* Normal: - * Normal: - lesser curvature -> smooth,lesser curvature -> smooth,

- greater curvature -> irregular,- greater curvature -> irregular,

- rugae- rugae

- duodenal cap -> triangular.- duodenal cap -> triangular.

CONTRAST STUDIES (9) – Barium MealCONTRAST STUDIES (9) – Barium Meal

* OGDS vs barium meal* OGDS vs barium meal

* * Pathology:Pathology: - Hiatus hernia - Hiatus hernia

(b) Rolling


(a) Sliding

- Linnitus plastica:- Linnitus plastica:

adenoca, lymphoma, breast mets, battery acid ingestion, TB, Crohn’s adenoca, lymphoma, breast mets, battery acid ingestion, TB, Crohn’s

and eusinophilic gastroenteritis.and eusinophilic gastroenteritis.


UlcersUlcers

Benign

Malignant

Duodenal ulcer


Erosive gastritisErosive gastritis


PolypsPolyps

CarcinomaCarcinoma


(4) Barium follow through and small bowel enema(4) Barium follow through and small bowel enema

* Differences in method:* Differences in method:- Barium follow through vs. SBE / enteroclysis - Barium follow through vs. SBE / enteroclysis

- view terminal ileum!- view terminal ileum!

* Normal barium follow-through and SBE:* Normal barium follow-through and SBE:- continuous column < 2.5cm diam.- continuous column < 2.5cm diam.

- transverse folds appear as filling defect 2-3mm width. - transverse folds appear as filling defect 2-3mm width.

If filled If filled transverse lines transverse lines

If collapsed If collapsed feathery feathery

- folds are most in the jejunum, least in the ileum.- folds are most in the jejunum, least in the ileum.

CONTRAST STUDIES (15) CONTRAST STUDIES (15) – Barium follow-thru’ & Small bowel enema– Barium follow-thru’ & Small bowel enema

- time-consuming - time-consuming procedure (2-3 hrs)procedure (2-3 hrs)

- require nasoduodenal intubationrequire nasoduodenal intubation- shorter timeshorter time- excellent mucosal detailexcellent mucosal detail

Normal barium follow through

SBE / Enteroclysis


MalabsorptionMalabsorptionSMALL BOWEL

LYMPHOMA


MalrotationMalrotation

Crohn’sCrohn’s

CONTRAST STUDIES (18) CONTRAST STUDIES (18) – Barium follow-thru’– Barium follow-thru’

LymphomaLymphoma Worm infestationWorm infestation

CONTRAST STUDIES (19) CONTRAST STUDIES (19) – Barium follow-thru’– Barium follow-thru’

(5) Barium enema(5) Barium enema

* barium enema vs. colonoscopy (vs. CT colonoscopy)* barium enema vs. colonoscopy (vs. CT colonoscopy)

** Method:Method: - Bowel prep! - Bowel prep!

- Control film!- Control film!

- Double contrast: Rectal tube, infuse barium,- Double contrast: Rectal tube, infuse barium,

drain, pump air. drain, pump air.

* Normal:* Normal: - Length variable +/- redundant loops. - Length variable +/- redundant loops.

- calibre decreases from caecum to sigmoid colon.- calibre decreases from caecum to sigmoid colon.

- ileocaecal valve may cause filling defect.- ileocaecal valve may cause filling defect.

- haustra may be absent in descending and- haustra may be absent in descending and

sigmoid regions.sigmoid regions.

CONTRAST STUDIES (20) - Barium EnemaCONTRAST STUDIES (20) - Barium Enema

Normal barium enema


Diverticulosis


Polyposis coliPolyposis coli


CarcinomaCarcinoma

‘Apple core’ appearance


TUBERCULOSIS INVOLVING

BOWEL

Strictures: Strictures: # ca, diverticular ds, Crohn’s, ischaemic colitis, TB, # ca, diverticular ds, Crohn’s, ischaemic colitis, TB, lymphogranuloma venereum, amoebiasis, radiation.lymphogranuloma venereum, amoebiasis, radiation.

‘THUMBPRINTING’(amoebiasis)

Diverticular disease


Crohn’s dz:Crohn’s dz:

# most freq inv lower ileum and colon# most freq inv lower ileum and colon

# early: - loss of haustration, narrowing and shallow # early: - loss of haustration, narrowing and shallow

ulceration. ulceration.

# ulcer + mucosal oedema # ulcer + mucosal oedema ‘cobblestone’ ‘cobblestone’

# later: deeper ulcer # later: deeper ulcer ‘rose-thorn’ or fissures. ‘rose-thorn’ or fissures.

# cx: - intra or extra-mural abscesses.# cx: - intra or extra-mural abscesses.

- fistulae.- fistulae.

- strictures: smooth and tapered ends.- strictures: smooth and tapered ends.

- when caecum inv - when caecum inv markedly contracted. markedly contracted.


Ulcerative colitis:Ulcerative colitis:

- similar to Crohn’s dz BUT (see below)- similar to Crohn’s dz BUT (see below)


CROHN’S DSCROHN’S DS

Shallow ulcers (aphtous)

Deep ulcer with tracking in the submucosa

Skip lesions


ULCERATIVE COLITIS

Loss of haustra

CROHN’S Recto-vaginal fistula


Intussusception

Hirschsprung’s ds


ULTRASOUNDULTRASOUND(1) General considerations(1) General considerations

- preparation- preparation

- normal anatomy: solid organs + biliary tree + vessels + - normal anatomy: solid organs + biliary tree + vessels + lymph nodes. lymph nodes.

- echogenicity: pancreas, liver, spleen, kidney.- echogenicity: pancreas, liver, spleen, kidney.

hyper hypohyper hypo

- appearances of various tissues:- appearances of various tissues:

fat = hyper; fat = hyper;

fluid = hypo with posterior acoustic enhancement;fluid = hypo with posterior acoustic enhancement;

calculi/ bone = hyper with post ac shadowing;calculi/ bone = hyper with post ac shadowing;

gas = shadowing.gas = shadowing.

NORMAL:NORMAL:

Liver

Pancreas

Spleen

Kidney

Gallbladder

Aorta

&

IVC

Lymph nodes

NORMAL:NORMAL:

Oesophagus

Stomach

Small bowel

Gas in bowel

NORMAL:NORMAL:

Cirrhosis

PATHOLOGY:PATHOLOGY:

Abscesses

Metastases

Lymphoma

Cyst

PATHOLOGY:PATHOLOGY:

Ascites

PV thrombosis

Cholecystitis with calculi

COMPUTED TOMOGRAPHY & COMPUTED TOMOGRAPHY & MAGNETIC RESONANCE IMAGING (1)MAGNETIC RESONANCE IMAGING (1)

(1) General considerations(1) General considerations

* * Differences between CT and MRI.Differences between CT and MRI.

* Windowing in CT, and sequences in MRI.* Windowing in CT, and sequences in MRI.

* Various densities in CT and intensities in MRI.* Various densities in CT and intensities in MRI.

CTCT MRIMRI

T2WT2W T1WT1W


PathologyPathology

Hepatic cystsHepatic cysts

CTCT

MRIMRI

T1WT1W

T2WT2W

HaemangiomaHaemangioma

NECTNECT Contrasted CTContrasted CT T2W MRIT2W MRI


Pancreatic CaPancreatic Ca

6 months later6 months laterPost-opPost-op 3 months later3 months later

ANGIOGRAPHY & ANGIOGRAPHY & INTERVENTIONAL RADIOLOGY (1)INTERVENTIONAL RADIOLOGY (1)

(1)(1) Types:Types:

- Flush aortogram- Flush aortogram

- Inferior vena cavogram / SVCgram- Inferior vena cavogram / SVCgram

- Selective: (according to vessels) hepatic artery, renal, spleen, - Selective: (according to vessels) hepatic artery, renal, spleen,

pancreas, coeliac axis, SMA, IMA, uterine artery. pancreas, coeliac axis, SMA, IMA, uterine artery.

- may include intervention: - may include intervention:

chemoembolization, coil/glue embolization, chemoembolization, coil/glue embolization,

stenting. stenting.

(2)(2) Indications:Indications:

- tumour / haemangioma, bleeding- tumour / haemangioma, bleeding, , pre-op … etcpre-op … etc

ANGIOGRAPHY & ANGIOGRAPHY & INTERVENTIONAL RADIOLOGY (2)INTERVENTIONAL RADIOLOGY (2)

Late phaseLate phase

MULTIFOCAL HEPATOMAMULTIFOCAL HEPATOMA

ANGIOMAANGIOMA

Post-embolisationPost-embolisationArterial phaseArterial phase

OTHER IMAGING METHODS (1)OTHER IMAGING METHODS (1)(1) Endoscopic retrograde cholangio-pancreatogram(1) Endoscopic retrograde cholangio-pancreatogram

(2) Percutaneous transhepatic cholangiogram(2) Percutaneous transhepatic cholangiogram

StoneStone

StoneStone

OTHER IMAGING METHODS (2)OTHER IMAGING METHODS (2)

(3) T-tube cholangiogram(3) T-tube cholangiogram (4) Radionuclide imaging (4) Radionuclide imaging

(I) GIT bleed(I) GIT bleed(II) IDA scan(II) IDA scan

MECKEL’S DIVERTICULUM

THE END !THE END !

imaging of the abdomen & the gastrointestinal

Documents

mid small bowel

small bowel infarction

bowel gas pattern

obs of small

normal gas

loop obstruction

mechanical obstruction

maximal dilatation usu