BASIC GI RADIOLOGY THE “FLAT” PLATE Michael Maristany, MD Janis Letourneau, MD After: Robert S. Perret, MD

KUB/Abdominal plain film Most common abdominal radiograph Patient supine Often combined with upright (CXR)

KUB

Normal KUB

KUB K kidney U ureter B bladder Term KUB indicates that the kidneys, ureters, and bladder are on the film But these organs are not necessarily seen on the image

K K u u KUB – Backwards u u B

KUB Paradoxically, organ system of greatest interest is often GI tract Small bowel situated centrally Large bowel located on periphery

colon small bowel colon rectum

Contrast filled stomach and small bowel

Contrast filled Colon

Miller-Abbott decompression tube For intestinal obstruction

KUB

KUB’s Why order them, anyway? > 85% (for pain, colic, nausea, etc) KUB will be non-contributory or normal

Why can KUB be useful? Bowel gas pattern characterization Detection of free air Abnormal calcifications Detection of organomegaly Discovery of abdominal masses Evaluation of bony structures Surgical / other medically relevant history

Bowel Gas Pattern Four major patterns Ileus Obstruction Gasless Normal “Free” air

Abnormal Bowel Gas Pattern: Small Bowel Obstruction Dilated loops of bowel SBO – (small bowel obstruction) Adhesions Less likely inflammatory/neoplastic Colonic obstruction More often of malignant etiology

Small Bowel Obstruction Dilated loops of small bowel (>3 cm) KUB With air/fluid levels on upright view Stair-step pattern to air/fluid levels Gasless colon

Normal Abnormal

Dilated small bowel - KUB Air/fluid levels on upright

PFs => SBO CT ABDOMEN: SBO Transition point – luminal caliber

Normal KUB

What’s likely dx? Common etiologies?

FREE (INTRAPERITONEAL) AIR KUB is not the best exam; upright or LLQ views helpful Think also of CT; not only good for detection, but for cause

KUB – Abnormal Ca++ Calcifications Gallstones Kidney stones Vascular Masses with calcifications (myoma, AAA) 20% < will be calcified >75% will be calcified

KUB - gallstones

KUB - Porcelain Gallbladder (or very large calcified stones)

ERCP Gallstones? Most gallstones will not be seen on KUB – not sufficiently calcified

KUB - kidney stones Kidney stones will often be visualized Related to extent of calcification Detection limit 1-2 mm Overlying intestinal gas limiting Obesity limiting

Kidney Stones

Other Calcified Abnormalities Uterine myomas Pancreatic ductal calcifications Vascular calcification Appendicolith Neoplasms sarcoma, testicular cancer, neuroblastoma Old hematomas

Uterine Myoma

CHRONIC PANCREATITIS

Calcified Uterine arteries

Appendicolith

Splenic hematoma Injection granulomata

Patient Detained Miami International

Non-calcified mass or mass effect Major limitation of plain films Organomegaly (multifocal dz vs diffuse) Neoplasm, abscess, hematoma Free peritoneal fluid (distribution of SB) Difficult to differentiate Relatively homogeneous Soft tissue density Merit of CT and MRI

Non calcified mass effect

OTHER GI IMAGING MODALITIES Esophagram Upper GI Series Small Bowel Follow-Through Barium Enema (or Contrast Enema) CT and CT Colonography ERCP MRCP US

UGIS and SBFT

AC Barium Enema

UNKNOWN CASE 52 yo man from Boston Bloody diarrhea Following half-marathon (CCC and poor training)

Thumb-printing: colonic wall edema Inflammation, ischemia, diffuse mural infiltration

CONSIDERATIONS UNKNOWN (REAL) CASES Patient age and gender Clinical symptoms Underlying diseases Including psychiatric (case of gym sock) Need for additional views (one at least) Localize mass or foreign body Deductive reasoning……….

Not the usual “stacked” coin appearance

And not causing GOO

More typical “stacked” coins