Acute abdominal series: Difference between revisions

Latest revision as of 13:57, 18 March 2019

Technique

3 Films:

Upright chest film
- Rule-out free air
Upright abdominal film
- Look for air-fluid levels
Supine abdominal film (KUB = just supine film)
- Width of bowel loops most visible (estimate of amount of distention)

If patient does not tolerate upright position, left lateral decubitus abdominal film can substitute

Interpretation

Normal
Small bowel obstruction
Large bowel obstruction (Cecal volvulus; black arrows).
Free intra-abdominal air below the diaphragm.
Body-packing with multiple foreign bodies ("balls" of hashish).
Button battery in stomach.
Gallstones (not sensitive)
Toxic megacolon
Rectal foreign body

Differentiating large and small bowel

Location	Size	Lines
Small bowel	3 cm	All the way through the bowel (plica circulares)
Colon	6 cm	Only halfway through the bowel (haustra)
Cecum	9 cm

Small bowel obstruction

Air in colon or rectum makes complete obstruction less likely (esp if symptoms >24hr)
Abdominal x-ray has poor Sn and Sp for SBO
- If concerned need CT

Indications

Ruling out free air under the diaphragm (e.g. perforated ulcer)
Ruling out radio-opaque abdominal foreign body (e.g. swallowed battery)
Ruling in bowel obstruction (i.e. to avoid need for subsequent CT scan)

Do NOT use as the sole study to rule out bowel obstruction (poor sensitivity)
Do NOT use to rule out generalized peritonitis (almost no sensitivity for diagnoses such as appendicitis)
Do NOT use to diagnose constipation (many patient with acute abdomen will have "copious stool")

Incidental findings

Gallstones (not always radiodense)

@@ Line 1: / Line 1: @@
-==Background==
+==Technique==
-*Differs from KUB in that patient is upright vs supine on KUB
+Films:
+#Upright chest film
+#*Rule-out free air
+#Upright abdominal film
+#*Look for air-fluid levels
+#Supine abdominal film (''KUB = just supine film'')
+#*Width of bowel loops most visible (estimate of amount of distention)
-==Diagnosis==
+''If patient does not tolerate upright position, left lateral decubitus abdominal film can substitute''
-*Films
-**Upright chest film: r/o free air
-**Upright abd film: air-fluid levels
-**Supine abd film: width of bowel loops most visible (estimate of amount of distention)
-*Air in colon or rectum makes complete obstruction less likely (esp if symptoms >24hr)
-*If pt does not tolerate upright position left lateral decub abd film can substitute
+==Interpretation==
+<gallery mode="packed">
+File:Medical X-Ray imaging ALP02 nevit.jpg|Normal
+File:SBO plain.png|[[Small bowel obstruction]]
+File:Cecalvolvulus.png|Large bowel obstruction (Cecal [[volvulus]]; black arrows).
+File:Free air under diaphram.png|Free intra-abdominal air below the diaphragm.
+File:Abdominal foreign body.png|Body-packing with multiple foreign bodies ("balls" of hashish).
+File:Battery in stomach.png|[[Esophageal foreign body|Button battery in stomach.]]
+File:StonesXray.png|[[Gallstones]] (not sensitive)
+File:Toxisches Megacolon bei Colitis ulcerosa.jpg|[[Toxic megacolon]]
+File:Rectal_fb.JPG|[[Rectal foreign body]]
+</gallery>
-To differentiate large and small bowel:
+===Differentiating large and small bowel===
-*Small bowel has lines (plica circulares) all the way through the bowel
+{| class="wikitable"
-*Large bowel has lines (haustra) only halfway through the bowel
+| align="center" style="background:#f0f0f0;"|'''Location'''
+| align="center" style="background:#f0f0f0;"|'''Size'''
+| align="center" style="background:#f0f0f0;"|'''Lines'''
+|-
+| Small bowel||3 cm||All the way through the bowel (plica circulares)
+|-
+| Colon||6 cm||Only halfway through the bowel (haustra)
+|-
+| Cecum||9 cm||
+|}
+===[[Small bowel obstruction]]===
+*Air in colon or rectum makes complete obstruction less likely (esp if symptoms >24hr)
+*Abdominal x-ray has poor Sn and Sp for [[SBO]]
+**If concerned need CT
-Bowel Diameters: 3/6/9 rule
+==Indications==
-*Small bowel - 3 cm
+*Ruling out free air under the diaphragm (e.g. perforated ulcer)
-*Colon - 6 cm
+*Ruling out radio-opaque abdominal foreign body (e.g. swallowed battery)
-*Cecum - 9 cm
+*Ruling '''in''' bowel obstruction (i.e. to avoid need for subsequent CT scan)
+;Do NOT use as the sole study to rule out bowel obstruction (poor sensitivity)
+;Do NOT use to rule out generalized peritonitis (almost no sensitivity for diagnoses such as [[appendicitis]])
+;Do NOT use to diagnose constipation (many patient with acute abdomen will have "copious stool")
-Abdominal x-ray has poor Sn and Sp for SBO
+==Incidental findings==
-*If concerned need CT
+*[[Gallstones]] (not always radiodense)
 ==See Also==
-*[[SBO]]
+*[[Abdominal pain]]
 [[Category:GI]]
-[[Category:Rads]]
+[[Category:Radiology]]