Ultrasound is the imaging modality of choice for the biliary tree. But the gallbladder isn't fixed to the body wall like other organs — it moves, it hides, and it lies to you when the patient just ate.
Find it, interrogate it in two axes, press on it, measure the duct. That's the whole exam.
Curated from the POCUS 101 Abdominal Ultrasound Made Easy: Step-By-Step Guide. This page is the pocket version — go there for the labeled images, clips, and probe-position photos.
Abdominal preset. Phased array works through rib spaces if that's what's on the machine.
Start supine. If the view is poor, roll to left lateral decubitus — it's the single highest-yield move in this exam.
Probe under the right costal margin near the midclavicular line, indicator toward the head. Sweep along the margin.
Subcostal sweep · indicator cephalad · patient holds a deep breath
Sweep the probe along the costal margin, fanning up under the ribs, until an anechoic, pear-shaped structure appears within the liver's inferior edge. If bowel gas is in the way, go intercostal — scan through the rib spaces using the liver as your window.
Long axis first · then rotate 90° for short axis · fan through the entire organ
In long axis, fan completely through the gallbladder side to side. In short axis, sweep fundus to neck. Stones hide in the neck — a "normal" fundus means nothing if you never saw the neck.
Probe pressure directly over the visualized gallbladder
A sonographic Murphy's sign is maximal tenderness when you push with the probe directly over the gallbladder you can see on screen — not just "the RUQ hurts." It is the most sensitive sonographic finding for cholecystitis (roughly 86–88%).
Anterior wall in short axis · CBD at the portal triad
Measure the anterior gallbladder wall (the posterior wall is falsely thickened by acoustic enhancement). Normal is ≤3 mm.
For the CBD: find the portal triad in cross-section (the "Mickey Mouse" — portal vein head, CBD and hepatic artery ears), then rotate to trace the duct in long axis anterior to the portal vein. Use color Doppler to confirm the duct is the structure without flow.
| Finding | Threshold | Means |
|---|---|---|
| Anterior wall | > 3 mm | Wall thickening — supports cholecystitis, but nonspecific (ascites, CHF, low albumin thicken walls too) |
| Sonographic Murphy's | present | Most sensitive single finding for cholecystitis (~86–88%) |
| Pericholecystic fluid | present | Supports cholecystitis; also nonspecific alone |
| GB distension | > 4 cm TR / > 9 cm long | Distension — a soft, supporting finding |
| CBD | < 6 mm | Normal. Allow ~1 mm per decade over 60; up to ~10 mm can be normal post-cholecystectomy |
| Stones + Murphy's | together | Stones plus a positive sonographic Murphy's is highly predictive of acute cholecystitis |
Pattern beats any single number: stones + Murphy's + thick wall + pericholecystic fluid tells one story. An isolated thick wall in an anasarcic patient tells another.
An impacted stone in the gallbladder neck or cystic duct is the lesion that causes cholecystitis — and the easiest one to miss. Fan through the neck deliberately, every time.
Position change is your mobility test: stones layer with gravity, polyps and adherent sludge balls stay put. It also un-stacks bowel gas from your window.
Fluid-filled duodenum sits right next door and fools everyone once. Watch for peristalsis, and trace your structure to the portal triad before you believe it.
A contracted gallbladder after a meal has a thick wall and no lumen — a setup for both false positives and "I can't find it." Ask when they last ate before you over-read the wall.
Refraction at the gallbladder neck creates an edge shadow that mimics a stone's shadow. A true stone shadow comes from an echogenic focus, not from a curved wall.
Stones? Murphy's? Wall? Fluid? Duct? That's the exam. Ductal stones themselves are hard to see — a dilated CBD is your surrogate, and MRCP/radiology takes it from there.
A starting template for the POCUS note. Text in brackets [ ] and pick-lists in { } are fields to complete. Save it as a SmartPhrase, then edit every field to match the actual study.
POINT-OF-CARE ULTRASOUND: RUQ / BILIARY
Indication: RUQ / epigastric pain [***]
Exam type: Focused / limited, bedside
Operator: @ME@ Interpretation: independent, real-time
Probe: curvilinear
FINDINGS
- Gallbladder: {visualized : not visualized}
- Gallstones: {none : present, {mobile : non-mobile}}
- Sonographic Murphy's sign: {negative : positive}
- Anterior GB wall: {normal <=3 mm : thickened *** mm}
- Pericholecystic fluid: {none : present}
- Common bile duct: *** mm, {normal : dilated}
IMAGE QUALITY: adequate / limited by [***]
Images saved and archived to [PACS / Qpath / ***].
IMPRESSION: {no sonographic evidence of cholecystitis :
findings concerning for acute cholecystitis : ***}.
I personally performed and interpreted this study.
Electronically signed: @ME@ @TD@ @NOW@
Sample template only — not a validated institutional SmartPhrase. Verify wording, image-archival, and attestation requirements against your department's POCUS credentialing, coding, and compliance policies before clinical use. Documentation supports, but does not replace, the medical record and QA workflow.