1
Small intestine
imaging
dr sumer yadav
2
3
Indications for small bowel
investigations
• Investigation of non-specific symptoms such as
pain,distension,bloating,diarrhoea
• Suspected inflammatory bowel
disease,includingexclusion of small bowel disease in
Crohn’s colitis
• Partial small bowel obstruction
• Obscure G I bleeding,iron deficient anaemia or bleeding
per rectum with normal upper G I endoscopy and
colonoscopy
• Definition of anatomy,of fistulas or malrotation
• Exclusion of malignancy,for example,complicating
coeliac disease
4
Difficulty in investigation
• Median lengthof 5.7m
• Difficult to visualise by location and anatomy
• Investigations must traverse proximal or distal
gut,and then negotiatea tortuous course
• Movement,with consequent artefact
• Radiation dose
• Patient acceptability of for example,NG
tubes,MRI scanners
• Low yield due to inappropiate referrals
• Interpretation of images
5
KEY POINT 1
• The small bowel is difficult to image and
studies of all techniques are limited by the
lack of a gold standard reference and
agreed criteria for referral
6
Techniques
• Conventional radiography
• Bariummeal follow through& enteroclysis
• Sonography
• CT-CT enteroclysis,CTenterography
• MRI-MRenteroclysis
• Capsule endoscopy
• Enteroscopy –push enteroscopy,push-pull
enteroscopy[also called double-balloon] and
intraoperative enteroscopy
7
Conventional Xrays
• Preferred initial radiographic investigation
• Diagnostic in 50-60%
• Radiographs done are
1.Supine Abdomen-bladder should be emptied before the
film and film should include area from diaphragm to
hernial orifices
2.Chest Radiograph- superior to erect abdomen to detect
pneumoperitoneum
Chest disease may mimic SBO
3.Erect Abdomen-air fluid level are seen .normal two may
be seen at D-Jflexure and terminal ilenm
8
Difference between large & small
intestine
• large bowel small bowel
• Haustra present absent
• Valvulae
conniventes absent present
loops pheripheral central
9
SBO IN FPA
10
FPA
Centrally placed small bowel loop
Valvulae conniventes
11
Rigler’sign
12
Barium meal follow through
• 500 ml of 42%w/v barium mixture is
ingested,fluroscopic and over head radiographs
at 15-30 minutes intervals,continue till
ileoceacal valve,when barium has reached
caecum,with targeted fluroscopy of special area
of interest.
• Manual palpation of the abdomen facilitates
movement of contrast and assesment of fixation
of bowel loops.
13
Figure
14
Figure
• X-ray image from a small bowel series showin
15
Saddle bags
16
Classic radiographic string sign
17
Ca cecum invading terminal ileum
18
Lymphoma mid ileum
19
carcinoid
20
• Radiograph from double-contrast upper GI
showing a normal duodenum.
21
• Radiographic appearance of Crohn's
disease of the terminal ileum. Nodularity,
ulceration, narrowing, and irregularity ...
22
Aphthoid ulceration of terminal ileum (small arrows)- Note also
"cobblestoning" (larger arrows).
23
Typical features of Crohn's disease of the distal ileum
including fissure ulcers (small arrows), longitudinal ulcers
(arrowhead), "cobblestoning" (open arrows), aphthoid
ulcers (curved arrow) and stricturing. ic=ileocaecal valve
24
Crohn 's disease of distal ileum with stricturing and sacculation on
the antimesenteric aspect (curved arrows), and fissure ulcers
(small arrows). Open arrow points to ileo-caecal valve
25
Backwash ileitis" due to ulcerative colitis. Note features of chronic ulcerative
colitis in right colon, patulous ileocaecal valve, dilated distal ileum with
granular mucosa.
26
Chronic ileocaecal tuberculosis. The caecum and ascending colon are
retracted craniad and are fibrotic. scarred and saccilated (curved
arrows). The terminal ileum in this patient is relatively patulous
(straight arrows) and probably nodular. v=ileocaecal valve.
27
Nodular filling defects in small bowel of AIDS
patient (same of which are arrowed) are consistent
with the submucosal deposits of Kaposi sarcoma.
Disease was present elsewhere in the bowel.
Although unverified in this patient, the thickened
folds and pa or coating probably represent co-
existent opportunistic infection - most likely
cryptosporidium.
28
Small bowel non-Hodgkin's lymphoma. Enteroclysis examination demonstrates a
segment of ileum in the right iliac fossa with wall thickening, destruction of the normal
fold pattern and aneurysmal ulceration (arrowed) and mass effect
29
Benign lymphoid hyperplasia of distal ileum. Ileocaecal valve is arrowed.
30
Jejunal diverticulosis on enteroclysis examination. Multiple
moderate-sized and large diverticula present.
31
Meckel's diverticulum (arrowed) demonstrated on enteroclysis in a young
patient with recurrent melaena.
32
Multiple band adhesions of small
bowel in left iliac fossa causing
retraction, tenting and fixation of
several adjacent loops.
33
Acute small bowel ischaemia.
Small bowel barium study
shows partial functional
obstruction, proximal to diffuse
spastic narrowing of ileum with
thickened folds and thick walls.
There is a ''picket fence"
pattern in places (arrowed).
c=colon.
34
Small bowel ischaemia.
Same patient as slide
33 CT after intravenous
contrast. Note "target"
sign in thickened ileal
loops in right iliac fossa
(arrowed), oedema in
adjacent mesentery and
fluid filled obstructed
bowel to left of midline.
Bowel had returned to
normal a few weeks
later on follow up
contrast study (patient
then asymptomatic).
35
Advntages
• Relative ease of cocept and its
execution,the availability of equipment and
expertise,the acceptence to the
patient,and a relatively lower radiation
dose
36
Disadvantage
• Limited ability to distinguish
abnormalit,given that there may be many
overlying loops of small intestine
• Length of examination
• Lack of complete distention of small bowel
37
Small bowel enteroclysis
• The intubation and infusion of small bowel by
barium,challenges the distensibility of bowel
wall,exagerating the effects of mild or subclinical
obstruction,demonstrates mucosal detail more
readily
• Technique –infusion of 30-40%w/v at 60-
90mi/min after duodenal intubation.
• Double contrast enteroclysis infusion of 60-
95%w/v barium,followed by infusion of air/methyl
cellulose to distend lumen leaving a thin coating
of barium.
38
Advantages
• Shorter examination time
• Better distension
• Greater positive and negative for a wide
range of S B pathology,including
strictures,adhesions and intrinsic SB
disease[eg sprue]
39
Disadvantage
• Patient discomfort
• Higher radiation dose
• Gastroduodenal disease may not be seen
• More experienced radiologist required
40
Key point 2
• Barium contrast studies are widely avilable
but yield is low
41
Ulrtasonograpny
• Trans abdominal ultrasound
• Advantages
• 1.cheap
• 2.quick
• 3.acceptable to patient
• 4.no ionising radiation-important in Crohn’s
disease patient who may require many
investigations over a life time.due to this popular
wiyh paediatricians
• 5.extraluminal information
• 6.dynamic changes
42
• Disadvantage
• 1.operator dependent modality
• 2.lack of standardisation
• 3.less useful in obese[images are better in
children] or in the presence of large
volumes of bowel gases
43
Studies with of USG
• Studies concentrated for use in crohn’s disease
• It shows bowel wall thickening,presence of mesenteric fat wrapping.These
are used as marker of disease activity
• Other sign includes pattern of vascularisation,presence of free peritoneal
fluid and mesenteric lymphadenopathy
• Direct extra luminal information-presence of abscesseswhich may be
missed with small bowel contrast studies
• Compared with small bowel follow through of the ileum,ileal bowel wall
thickening of more than 2.5 mm gave comparative sensitivity of
75%,specificity of 92% and P P value of 88%
• Sup. Mesenteric artery doppler does not corelate with disease severity
• Small bowel follow through is more sensitiveand still indicated on strong
clinical grounds in spite of normal USG result
• There is lack of agreed definition of the bowel wall thickening that may be
considered abnormal
• Other disease processes, such as ileal TBand backwash ileitis of UC
44
New development in USG
• Supplementation with oral contrast
• USG after distention of the small bowel
with PEG electrolyte balanced solution
• In this method greater length of diseased
bowel recognised and detection of jejunal
lesions other wise missed with plain USG
• By Calabrese et al
• cont.
45
• Pareante et al used nonabsorbable
anechoic contrast to distend bowel with
proven crohn’s disease
• In this stricture was better seen
• Authors that USG with contrast may be
first-line investigation and comparable with
small bowel enema
46
Doppler USG
• Evaluate changes seen in vasculature with
bowel inflamation
• Incresed vascularity is seen in the bowel
• Sup. Mesenteric artery images may
indicate disease activity
• But there are small no. of studies there
fore the role of Doppler USG is still to be
established
47
• Ultrasound showing blood flowing
from intestines into liver. Image on
the left: routine. On the right with
power Doppler.
48
Ultrasound of thickened bowel. Relatively hypoechoic thick walls (arrowed) with
echogenic lumen. Appearances are non-specific - in this case, Crohn's disease of
the ileum
49
Ultrasound image demonstrates pelvic abscess and enterocutaneous
fistula complicating Crohn's disease. Abscess (arrows) contains
internal echoes. Hyperechoic foci (arrowhead) represent gas in bladder
(b) wall.
50
Same patient as previous slide. CT of pelvis
demonstrates thickened loop of ileum (small arrows),
fistula to bladder (arrowhead) and gas in bladder wall
(curved arrow) and in non-dependent aspect of bladder
itself. More cranial image better showed associated
abscess.
51
• An ultrasound miniprobe
(20 MHz) is placed in the
ascending part of the
partly water-filled jejunal
lumen in a patient with
CD. The layers of the wall
are seen and also an
erosion/superficial ulcer
(b) can be observed. The
edge of the lesion is
indicated
52
Key point 3
• USG may be very useful and acceptable
in identifying terminal ileitis,particularly in
children ,but its use is very observer-
dependent and expertise in bowel USG is
not widely available.
53
CT scan
C T has central role in imaging abdomen
CT can depict bowel
thickening,fistulas,abscesses and
lymphadenopathy
• Bowel wall assessment during different phases
of scanning with i.v. contrast allows assesment
of perfusion
• Intramural gas may be detected
• MDCT can reconstruct images in any angle
54
C T SCAN
• Advantages
• 1.quick
• 2.acceptable to most of the patient
• 3. major advantage is –provide
extraluminal information over luminal
contrast studies
55
Disadvantages
• Ionising radiation
• It is static rather than dynamic .This make
differentiation b/w skip lesionsand
peristalsis difficult
• Artefact which may arise from the lack of
physiological distension
56
CT ENTEROCLYSIS
• Newer more specific technique for small
bowel
• Require same nasojejunal intubation and
small bowel distension with contrast as
barium enteroclysis
• More quick
• Ability to follow the progression of contrast
is lacking
57
indicatinos
• Suspected malignancy
• Known inflamatory bowel disease
• Occult G I bleed
• Low grade small bowel obstruction
• Refractory coeliac sprue
58
Studies with CT ENTEROCLYSIS
• It demonstrated fistula which was not shown by
other modality
• Aid in the diagnosis of ileoceacal TB by
demonstrating necrotic mesenteric lymph node
• In refractory coeliac sprueit demonstrated
ulceration,lymphoma,adenocarcinomaof jejunum
• Boudiaf et al
• cont.
59
• Important-early crohn’s disease may be better
demonstrated on small bowel enema
• In patients with very high index of suspicion,use
of both tests may be appropiate
• More abnormality detected with CTenteroclysis
than small bowel enema,but principally with
extra luminal manifestation
• Minordi et al
60
CT ENTEROGRAPHY
• Generic term for C T investigation where small bowel is distended
with orally ingested contrast as opposed to that delievered by
nasojejunal tube
• Primary reason for abandoning the naso jejunal tube is patient
acceptibility
• Enterography may prove itself as effective as enteroclysis
• Oral contrast agent used –water,methylcellulose,PEG,dilute barium
solution
• The advantage of oral hyperhydration to achieve small bowel
distensibility is that in future it could be added to the general
CTabd/pelvis for abdominal pain of uncertain etiology
• Mazzeo et al
61
CT with free air and bowel loop
62
• Enterovesical fistulas
63
64
Key point 4
• CT enteroclysis shold be at least as good
as small bowel enema,and will provide
extraluminal informatiom.
• Images are static and repeated studies
expose to ionising radiation
65
M R Imaging
• Give extra luminal information and permit
multiplanar reformatting without ionising
radiation
• Preferable in children and reproductive age
group
• Distinguish active disease with fibrosis
• Definition of tissue planes is better than CT
• Real time functional information may be
obtained with MR fluroscopy and this is a distinct
advantage over CT
66
• Contrast by physiological luminal content
• Purposeful distention by drinking or by
enteroclysis
• Positve gadolinium based or negative iron
based contrast used in MR entroclysis
• MR demonstrate In crohn’s disease –
muralulcer,fistulas,pseudopolyp,thickening
,stenosisand pre-stenotic dilatation
67
Disadvantage
• Patient compliance-many patient fails to
complete the scan
• Long timeaffect image quality,as artefact
may be produced by peristalsis
• vomiting and rectal evacuation
68
CT V/S MR
• CT in the absence of luminal distention is
not sensitive for excluding small bowel
pathology
69
MR V/S CONVENTIONAL
RADIOGRAPHY
• No difference in finding of muralNo difference in finding of mural
ulceration,pseudopolyp,stenosis,pre stenoticulceration,pseudopolyp,stenosis,pre stenotic
dilatation or fistuladilatation or fistula
• More exrta luminal information with MRMore exrta luminal information with MR
enteroclysis in crohn’s disease asenteroclysis in crohn’s disease as
abscesses,lymphadenopathy,small bowelabscesses,lymphadenopathy,small bowel
separation and colonic lesionseparation and colonic lesion
• Studies say that MR enteroclysis may be inferiorStudies say that MR enteroclysis may be inferior
in detecting subtle lesionsin detecting subtle lesions
• EUR RADIOLOGY 2006EUR RADIOLOGY 2006
70
KEY POINT 5
• MR enteroclysis may be equivalent to
other imaging modalities, but with the
advantage of dynamic imaging and no
ionising radiation
71
Enteroscopy
• Imp. Both diagnostic and therapeutic
• Ileoscopy as part of colonoscopy
• Push enteroscopy-Enteroscope which traverse
the proximal jejunum. Max. distance covered
150 cm
• Push-pull or Double Balloon enteroscopy
visualise entire small bowel
• Good result in obscure GI bleed
• Mucosal visualisation better than capsule
endoscopy
72
Disadvantages
• Invasive
• Risks of bleeding & perforation
• Lower patient acceptibility
• Limited expertise
73
Key point 6
• Push enteroscopy permits therapeutic
intervention but has limited reach.Double
Balloon enteroscopy may overcome this
but is very invasiveand not widely
available
74
Capsule endoscopy
• Direct luminal visualisation is aceived by the patient
swallowing a capsule containing a video
camera,microchip and transmitter,with images
transmitted to a receiver worn by the patient
• Important complication-impactation which may require
surgical removal.impactation rate 0.75%
• Contra indicated in stricturing Crohn’s disease,in
implanted pace maker,in swallowing disorder
• Patency capsule-capsules with a lactose body which
dissolves after 40 h to confirm the patency of the lumen
• Biopsy is not possible at present
• More small bowel pathology may be seen, leading to
further investigations, not all of which may be necessary
75
• It is of note thay,in patients with suspected crohn’s disease,capsule
endoscopy did not give rise to a significantly greater yield over any
modality,whereas it did in the known Crohn’s disease patient.
• This is most likely to be due to the heterogeneity of patients labelled
as ‘suspected Crohn’s disease’
• There is lack of consensus as to what constitutes Crohn’s disease
on capsule endoscopy.
• It may be hard to distinguish b/w Crohn’s disease and NASID
induced enteropathy
• Overall impression is that capsule endoscopy produces a greater
yield.
• Take home message is- it may be powerful in promoting its uptake
in G I world
76
Advantage
• Direct mucosal visualisation
• Patient acceptibility
• Lack of ionising radiation
77
Disadvantages
• Cost
• Reporting time
• Impaction
• Difficult to localise the lesion
• High miss rate
78
The capsule
79
Inner workings of capsule
80
Scanner
81
Key point 7
• The evidence points towarss capsule
endoscopy being superior to other
imaging modalities in known Crohn’s
disease.however,it is not used in those
with stricturing Crohn’s disease patients
due to risk of capsule retention.Its
usefulness in the patient with suspected
Crohn’s disease is less clear.
82
Implication for practice
• A department should be encoureged to ultrasound the terminal ileum of patient who
present with irritable bowel syndrome-type symptoms,in whom it is desiredto exclude
inflammatory bowel disease.
• Ultrasound should be performed by G I radoiologist expert in the field of bowel
sonography.
• Next tier of investigation should be CT enterography or enteroclysis,which should
replace barium enteroclysis,as result are similar but the latter is more comprehensive.
• Rigorous audit shold accompany the change in practice,to ensure standards remain
high and that results are as good as enteroclysis.
• For Crohn’s disease patient who may require repeated investigations over many
years,MR enteroclysis should be developed
• Finally ,capsule endoscopy should be available for investigation of lesions such as
angiodysplasia which are not seen on cross-sectional imaging.
• Recommendations for the investigation of obscure G I bleeding have been largely
established and are likely to comprise upper and GI endoscopy,followed by a repeat
UGI endoscopy as lesions are found at enteroscopy that would be within reach of the
initial study. This can be followed by capsule endoscopy, then enteroscopy
83
Key point for clinical practice
• The small bowel is difficult to image and studies of all techniques are limited by the
lack of a gold standard reference and agreed criteria for referral.
• Barium contrast studies are widely available but yield is low.
• USG may be very helpful and accepyable in identifying terminal ileitis,particularly in
children,but its use is very observer-dependent and expertise in bowel ultrasound is
not widely available.
• CT enteroclysis should be at least as good as small bowel enema,and will provide
extraluminal information.images are static and repeatwd studies,such as Crohn’s
patient might expect during a life time,may result in considerable exposure to ionising
radiation.
• MR enteroclysis may be equivalentto other imaging modalities,but with the advantage
of dynamic imaging and no ionising radiation.
• Push enteroscopy permits therapeutic intervention but has limited reach.Double
balloon enteroscopy may overcome this but is very invasive and not widely available.
• The evidence points towards capsule endoscopy being superior to other imaging
modalities in known Crohn’s disease although it cannot be used in a large subsection
of Crohn’s disease patients due to stricturing with consequent risk of capsule
retention.Its usefulness in suspected Crohn’s disease is less clear.
•Thanks
84

small intestine imaging

  • 1.
  • 2.
  • 3.
    3 Indications for smallbowel investigations • Investigation of non-specific symptoms such as pain,distension,bloating,diarrhoea • Suspected inflammatory bowel disease,includingexclusion of small bowel disease in Crohn’s colitis • Partial small bowel obstruction • Obscure G I bleeding,iron deficient anaemia or bleeding per rectum with normal upper G I endoscopy and colonoscopy • Definition of anatomy,of fistulas or malrotation • Exclusion of malignancy,for example,complicating coeliac disease
  • 4.
    4 Difficulty in investigation •Median lengthof 5.7m • Difficult to visualise by location and anatomy • Investigations must traverse proximal or distal gut,and then negotiatea tortuous course • Movement,with consequent artefact • Radiation dose • Patient acceptability of for example,NG tubes,MRI scanners • Low yield due to inappropiate referrals • Interpretation of images
  • 5.
    5 KEY POINT 1 •The small bowel is difficult to image and studies of all techniques are limited by the lack of a gold standard reference and agreed criteria for referral
  • 6.
    6 Techniques • Conventional radiography •Bariummeal follow through& enteroclysis • Sonography • CT-CT enteroclysis,CTenterography • MRI-MRenteroclysis • Capsule endoscopy • Enteroscopy –push enteroscopy,push-pull enteroscopy[also called double-balloon] and intraoperative enteroscopy
  • 7.
    7 Conventional Xrays • Preferredinitial radiographic investigation • Diagnostic in 50-60% • Radiographs done are 1.Supine Abdomen-bladder should be emptied before the film and film should include area from diaphragm to hernial orifices 2.Chest Radiograph- superior to erect abdomen to detect pneumoperitoneum Chest disease may mimic SBO 3.Erect Abdomen-air fluid level are seen .normal two may be seen at D-Jflexure and terminal ilenm
  • 8.
    8 Difference between large& small intestine • large bowel small bowel • Haustra present absent • Valvulae conniventes absent present loops pheripheral central
  • 9.
  • 10.
    10 FPA Centrally placed smallbowel loop Valvulae conniventes
  • 11.
  • 12.
    12 Barium meal followthrough • 500 ml of 42%w/v barium mixture is ingested,fluroscopic and over head radiographs at 15-30 minutes intervals,continue till ileoceacal valve,when barium has reached caecum,with targeted fluroscopy of special area of interest. • Manual palpation of the abdomen facilitates movement of contrast and assesment of fixation of bowel loops.
  • 13.
  • 14.
    14 Figure • X-ray imagefrom a small bowel series showin
  • 15.
  • 16.
  • 17.
    17 Ca cecum invadingterminal ileum
  • 18.
  • 19.
  • 20.
    20 • Radiograph fromdouble-contrast upper GI showing a normal duodenum.
  • 21.
    21 • Radiographic appearanceof Crohn's disease of the terminal ileum. Nodularity, ulceration, narrowing, and irregularity ...
  • 22.
    22 Aphthoid ulceration ofterminal ileum (small arrows)- Note also "cobblestoning" (larger arrows).
  • 23.
    23 Typical features ofCrohn's disease of the distal ileum including fissure ulcers (small arrows), longitudinal ulcers (arrowhead), "cobblestoning" (open arrows), aphthoid ulcers (curved arrow) and stricturing. ic=ileocaecal valve
  • 24.
    24 Crohn 's diseaseof distal ileum with stricturing and sacculation on the antimesenteric aspect (curved arrows), and fissure ulcers (small arrows). Open arrow points to ileo-caecal valve
  • 25.
    25 Backwash ileitis" dueto ulcerative colitis. Note features of chronic ulcerative colitis in right colon, patulous ileocaecal valve, dilated distal ileum with granular mucosa.
  • 26.
    26 Chronic ileocaecal tuberculosis.The caecum and ascending colon are retracted craniad and are fibrotic. scarred and saccilated (curved arrows). The terminal ileum in this patient is relatively patulous (straight arrows) and probably nodular. v=ileocaecal valve.
  • 27.
    27 Nodular filling defectsin small bowel of AIDS patient (same of which are arrowed) are consistent with the submucosal deposits of Kaposi sarcoma. Disease was present elsewhere in the bowel. Although unverified in this patient, the thickened folds and pa or coating probably represent co- existent opportunistic infection - most likely cryptosporidium.
  • 28.
    28 Small bowel non-Hodgkin'slymphoma. Enteroclysis examination demonstrates a segment of ileum in the right iliac fossa with wall thickening, destruction of the normal fold pattern and aneurysmal ulceration (arrowed) and mass effect
  • 29.
    29 Benign lymphoid hyperplasiaof distal ileum. Ileocaecal valve is arrowed.
  • 30.
    30 Jejunal diverticulosis onenteroclysis examination. Multiple moderate-sized and large diverticula present.
  • 31.
    31 Meckel's diverticulum (arrowed)demonstrated on enteroclysis in a young patient with recurrent melaena.
  • 32.
    32 Multiple band adhesionsof small bowel in left iliac fossa causing retraction, tenting and fixation of several adjacent loops.
  • 33.
    33 Acute small bowelischaemia. Small bowel barium study shows partial functional obstruction, proximal to diffuse spastic narrowing of ileum with thickened folds and thick walls. There is a ''picket fence" pattern in places (arrowed). c=colon.
  • 34.
    34 Small bowel ischaemia. Samepatient as slide 33 CT after intravenous contrast. Note "target" sign in thickened ileal loops in right iliac fossa (arrowed), oedema in adjacent mesentery and fluid filled obstructed bowel to left of midline. Bowel had returned to normal a few weeks later on follow up contrast study (patient then asymptomatic).
  • 35.
    35 Advntages • Relative easeof cocept and its execution,the availability of equipment and expertise,the acceptence to the patient,and a relatively lower radiation dose
  • 36.
    36 Disadvantage • Limited abilityto distinguish abnormalit,given that there may be many overlying loops of small intestine • Length of examination • Lack of complete distention of small bowel
  • 37.
    37 Small bowel enteroclysis •The intubation and infusion of small bowel by barium,challenges the distensibility of bowel wall,exagerating the effects of mild or subclinical obstruction,demonstrates mucosal detail more readily • Technique –infusion of 30-40%w/v at 60- 90mi/min after duodenal intubation. • Double contrast enteroclysis infusion of 60- 95%w/v barium,followed by infusion of air/methyl cellulose to distend lumen leaving a thin coating of barium.
  • 38.
    38 Advantages • Shorter examinationtime • Better distension • Greater positive and negative for a wide range of S B pathology,including strictures,adhesions and intrinsic SB disease[eg sprue]
  • 39.
    39 Disadvantage • Patient discomfort •Higher radiation dose • Gastroduodenal disease may not be seen • More experienced radiologist required
  • 40.
    40 Key point 2 •Barium contrast studies are widely avilable but yield is low
  • 41.
    41 Ulrtasonograpny • Trans abdominalultrasound • Advantages • 1.cheap • 2.quick • 3.acceptable to patient • 4.no ionising radiation-important in Crohn’s disease patient who may require many investigations over a life time.due to this popular wiyh paediatricians • 5.extraluminal information • 6.dynamic changes
  • 42.
    42 • Disadvantage • 1.operatordependent modality • 2.lack of standardisation • 3.less useful in obese[images are better in children] or in the presence of large volumes of bowel gases
  • 43.
    43 Studies with ofUSG • Studies concentrated for use in crohn’s disease • It shows bowel wall thickening,presence of mesenteric fat wrapping.These are used as marker of disease activity • Other sign includes pattern of vascularisation,presence of free peritoneal fluid and mesenteric lymphadenopathy • Direct extra luminal information-presence of abscesseswhich may be missed with small bowel contrast studies • Compared with small bowel follow through of the ileum,ileal bowel wall thickening of more than 2.5 mm gave comparative sensitivity of 75%,specificity of 92% and P P value of 88% • Sup. Mesenteric artery doppler does not corelate with disease severity • Small bowel follow through is more sensitiveand still indicated on strong clinical grounds in spite of normal USG result • There is lack of agreed definition of the bowel wall thickening that may be considered abnormal • Other disease processes, such as ileal TBand backwash ileitis of UC
  • 44.
    44 New development inUSG • Supplementation with oral contrast • USG after distention of the small bowel with PEG electrolyte balanced solution • In this method greater length of diseased bowel recognised and detection of jejunal lesions other wise missed with plain USG • By Calabrese et al • cont.
  • 45.
    45 • Pareante etal used nonabsorbable anechoic contrast to distend bowel with proven crohn’s disease • In this stricture was better seen • Authors that USG with contrast may be first-line investigation and comparable with small bowel enema
  • 46.
    46 Doppler USG • Evaluatechanges seen in vasculature with bowel inflamation • Incresed vascularity is seen in the bowel • Sup. Mesenteric artery images may indicate disease activity • But there are small no. of studies there fore the role of Doppler USG is still to be established
  • 47.
    47 • Ultrasound showingblood flowing from intestines into liver. Image on the left: routine. On the right with power Doppler.
  • 48.
    48 Ultrasound of thickenedbowel. Relatively hypoechoic thick walls (arrowed) with echogenic lumen. Appearances are non-specific - in this case, Crohn's disease of the ileum
  • 49.
    49 Ultrasound image demonstratespelvic abscess and enterocutaneous fistula complicating Crohn's disease. Abscess (arrows) contains internal echoes. Hyperechoic foci (arrowhead) represent gas in bladder (b) wall.
  • 50.
    50 Same patient asprevious slide. CT of pelvis demonstrates thickened loop of ileum (small arrows), fistula to bladder (arrowhead) and gas in bladder wall (curved arrow) and in non-dependent aspect of bladder itself. More cranial image better showed associated abscess.
  • 51.
    51 • An ultrasoundminiprobe (20 MHz) is placed in the ascending part of the partly water-filled jejunal lumen in a patient with CD. The layers of the wall are seen and also an erosion/superficial ulcer (b) can be observed. The edge of the lesion is indicated
  • 52.
    52 Key point 3 •USG may be very useful and acceptable in identifying terminal ileitis,particularly in children ,but its use is very observer- dependent and expertise in bowel USG is not widely available.
  • 53.
    53 CT scan C Thas central role in imaging abdomen CT can depict bowel thickening,fistulas,abscesses and lymphadenopathy • Bowel wall assessment during different phases of scanning with i.v. contrast allows assesment of perfusion • Intramural gas may be detected • MDCT can reconstruct images in any angle
  • 54.
    54 C T SCAN •Advantages • 1.quick • 2.acceptable to most of the patient • 3. major advantage is –provide extraluminal information over luminal contrast studies
  • 55.
    55 Disadvantages • Ionising radiation •It is static rather than dynamic .This make differentiation b/w skip lesionsand peristalsis difficult • Artefact which may arise from the lack of physiological distension
  • 56.
    56 CT ENTEROCLYSIS • Newermore specific technique for small bowel • Require same nasojejunal intubation and small bowel distension with contrast as barium enteroclysis • More quick • Ability to follow the progression of contrast is lacking
  • 57.
    57 indicatinos • Suspected malignancy •Known inflamatory bowel disease • Occult G I bleed • Low grade small bowel obstruction • Refractory coeliac sprue
  • 58.
    58 Studies with CTENTEROCLYSIS • It demonstrated fistula which was not shown by other modality • Aid in the diagnosis of ileoceacal TB by demonstrating necrotic mesenteric lymph node • In refractory coeliac sprueit demonstrated ulceration,lymphoma,adenocarcinomaof jejunum • Boudiaf et al • cont.
  • 59.
    59 • Important-early crohn’sdisease may be better demonstrated on small bowel enema • In patients with very high index of suspicion,use of both tests may be appropiate • More abnormality detected with CTenteroclysis than small bowel enema,but principally with extra luminal manifestation • Minordi et al
  • 60.
    60 CT ENTEROGRAPHY • Genericterm for C T investigation where small bowel is distended with orally ingested contrast as opposed to that delievered by nasojejunal tube • Primary reason for abandoning the naso jejunal tube is patient acceptibility • Enterography may prove itself as effective as enteroclysis • Oral contrast agent used –water,methylcellulose,PEG,dilute barium solution • The advantage of oral hyperhydration to achieve small bowel distensibility is that in future it could be added to the general CTabd/pelvis for abdominal pain of uncertain etiology • Mazzeo et al
  • 61.
    61 CT with freeair and bowel loop
  • 62.
  • 63.
  • 64.
    64 Key point 4 •CT enteroclysis shold be at least as good as small bowel enema,and will provide extraluminal informatiom. • Images are static and repeated studies expose to ionising radiation
  • 65.
    65 M R Imaging •Give extra luminal information and permit multiplanar reformatting without ionising radiation • Preferable in children and reproductive age group • Distinguish active disease with fibrosis • Definition of tissue planes is better than CT • Real time functional information may be obtained with MR fluroscopy and this is a distinct advantage over CT
  • 66.
    66 • Contrast byphysiological luminal content • Purposeful distention by drinking or by enteroclysis • Positve gadolinium based or negative iron based contrast used in MR entroclysis • MR demonstrate In crohn’s disease – muralulcer,fistulas,pseudopolyp,thickening ,stenosisand pre-stenotic dilatation
  • 67.
    67 Disadvantage • Patient compliance-manypatient fails to complete the scan • Long timeaffect image quality,as artefact may be produced by peristalsis • vomiting and rectal evacuation
  • 68.
    68 CT V/S MR •CT in the absence of luminal distention is not sensitive for excluding small bowel pathology
  • 69.
    69 MR V/S CONVENTIONAL RADIOGRAPHY •No difference in finding of muralNo difference in finding of mural ulceration,pseudopolyp,stenosis,pre stenoticulceration,pseudopolyp,stenosis,pre stenotic dilatation or fistuladilatation or fistula • More exrta luminal information with MRMore exrta luminal information with MR enteroclysis in crohn’s disease asenteroclysis in crohn’s disease as abscesses,lymphadenopathy,small bowelabscesses,lymphadenopathy,small bowel separation and colonic lesionseparation and colonic lesion • Studies say that MR enteroclysis may be inferiorStudies say that MR enteroclysis may be inferior in detecting subtle lesionsin detecting subtle lesions • EUR RADIOLOGY 2006EUR RADIOLOGY 2006
  • 70.
    70 KEY POINT 5 •MR enteroclysis may be equivalent to other imaging modalities, but with the advantage of dynamic imaging and no ionising radiation
  • 71.
    71 Enteroscopy • Imp. Bothdiagnostic and therapeutic • Ileoscopy as part of colonoscopy • Push enteroscopy-Enteroscope which traverse the proximal jejunum. Max. distance covered 150 cm • Push-pull or Double Balloon enteroscopy visualise entire small bowel • Good result in obscure GI bleed • Mucosal visualisation better than capsule endoscopy
  • 72.
    72 Disadvantages • Invasive • Risksof bleeding & perforation • Lower patient acceptibility • Limited expertise
  • 73.
    73 Key point 6 •Push enteroscopy permits therapeutic intervention but has limited reach.Double Balloon enteroscopy may overcome this but is very invasiveand not widely available
  • 74.
    74 Capsule endoscopy • Directluminal visualisation is aceived by the patient swallowing a capsule containing a video camera,microchip and transmitter,with images transmitted to a receiver worn by the patient • Important complication-impactation which may require surgical removal.impactation rate 0.75% • Contra indicated in stricturing Crohn’s disease,in implanted pace maker,in swallowing disorder • Patency capsule-capsules with a lactose body which dissolves after 40 h to confirm the patency of the lumen • Biopsy is not possible at present • More small bowel pathology may be seen, leading to further investigations, not all of which may be necessary
  • 75.
    75 • It isof note thay,in patients with suspected crohn’s disease,capsule endoscopy did not give rise to a significantly greater yield over any modality,whereas it did in the known Crohn’s disease patient. • This is most likely to be due to the heterogeneity of patients labelled as ‘suspected Crohn’s disease’ • There is lack of consensus as to what constitutes Crohn’s disease on capsule endoscopy. • It may be hard to distinguish b/w Crohn’s disease and NASID induced enteropathy • Overall impression is that capsule endoscopy produces a greater yield. • Take home message is- it may be powerful in promoting its uptake in G I world
  • 76.
    76 Advantage • Direct mucosalvisualisation • Patient acceptibility • Lack of ionising radiation
  • 77.
    77 Disadvantages • Cost • Reportingtime • Impaction • Difficult to localise the lesion • High miss rate
  • 78.
  • 79.
  • 80.
  • 81.
    81 Key point 7 •The evidence points towarss capsule endoscopy being superior to other imaging modalities in known Crohn’s disease.however,it is not used in those with stricturing Crohn’s disease patients due to risk of capsule retention.Its usefulness in the patient with suspected Crohn’s disease is less clear.
  • 82.
    82 Implication for practice •A department should be encoureged to ultrasound the terminal ileum of patient who present with irritable bowel syndrome-type symptoms,in whom it is desiredto exclude inflammatory bowel disease. • Ultrasound should be performed by G I radoiologist expert in the field of bowel sonography. • Next tier of investigation should be CT enterography or enteroclysis,which should replace barium enteroclysis,as result are similar but the latter is more comprehensive. • Rigorous audit shold accompany the change in practice,to ensure standards remain high and that results are as good as enteroclysis. • For Crohn’s disease patient who may require repeated investigations over many years,MR enteroclysis should be developed • Finally ,capsule endoscopy should be available for investigation of lesions such as angiodysplasia which are not seen on cross-sectional imaging. • Recommendations for the investigation of obscure G I bleeding have been largely established and are likely to comprise upper and GI endoscopy,followed by a repeat UGI endoscopy as lesions are found at enteroscopy that would be within reach of the initial study. This can be followed by capsule endoscopy, then enteroscopy
  • 83.
    83 Key point forclinical practice • The small bowel is difficult to image and studies of all techniques are limited by the lack of a gold standard reference and agreed criteria for referral. • Barium contrast studies are widely available but yield is low. • USG may be very helpful and accepyable in identifying terminal ileitis,particularly in children,but its use is very observer-dependent and expertise in bowel ultrasound is not widely available. • CT enteroclysis should be at least as good as small bowel enema,and will provide extraluminal information.images are static and repeatwd studies,such as Crohn’s patient might expect during a life time,may result in considerable exposure to ionising radiation. • MR enteroclysis may be equivalentto other imaging modalities,but with the advantage of dynamic imaging and no ionising radiation. • Push enteroscopy permits therapeutic intervention but has limited reach.Double balloon enteroscopy may overcome this but is very invasive and not widely available. • The evidence points towards capsule endoscopy being superior to other imaging modalities in known Crohn’s disease although it cannot be used in a large subsection of Crohn’s disease patients due to stricturing with consequent risk of capsule retention.Its usefulness in suspected Crohn’s disease is less clear.
  • 84.