Choledocholithiasis Detection on MRCP

Purpose	To detect choledocholithiasis on MRCP
Tag(s)
Panel	Abdominal
Define-AI ID	20020008
Originator	Luther B. Adair, II
Lead	Luther B. Adair, II
Panel Chair	Arun Krishnaraj
Panel Reviewers	Abdominal Panel
License	Creative Commons 4.0
Status	Public Comment
RadElement Set	RDES159

Clinical Implementation

Value Proposition

Choledocholithiasis is a potentially life-threatening but treatable emergency. AI meeting this use case would help in detecting, quantitating, and alerting both nonspecialists and radiologists to this potentially life-threatening abnormality. In clinical settings where a radiologist is not readily available, such detection would be of value to non-radiologists such as technologists who would perform a MRCP for this disease entity. In clinical settings where radiologists are available, such detection could be used to alert the radiologist and prioritize its reporting and notification to the treating physicians. One possible extension to this use case is to detect choledocholithiasis on MRCP and assess the need for further treatment with ERCP.

Narrative(s)

A 44-year old patient presents with constant right upper quadrant pain and is taken to the emergency room at which time an MRCP is ordered.

A 67-year old patient presents to an outpatient clinic with jaundice and right upper quadrant pain and is sent to the emergency room, at which time an MRI Abdomen with MRCP is ordered.

Workflow Description

The relevant images are obtained from modality and sent to PACS and the AI engine based on anatomic landmarks. The images are analyzed by the engine. The system then detects the relevant outputs providing associated categorical data or measurements. An alert message is sent to PACS from the engine with the information, identification, and graphics highlighting the common bile duct stone, the measurement of the stone, whether there is biliary ductal dilatation and measurement of the common bile duct, whether there is periductal fluid present, and whether there is gallbladder distention.

An algorithm evaluates the relevant MRCP sequences and categorizes whether a common bile duct stone is present, absent, or undetermined. If present, it then measures the stone; assesses whether biliary ductal dilatation is present, absent, or undetermined with a measurement of the common bile duct; assesses whether periductal fluid is present, absent, or undetermined; assesses whether the gallbladder is distended or not distended with a measurement of the gallbladder lumen from wall to wall. For cases returned where the algorithm returns a common bile duct stone present, the recommendation for ERCP is made and the radiologist is made aware. For cases returned where the algorithm returns a stone absent or undetermined, but there are any secondary output elements present (biliary ductal dilatation, periductal fluid, or a distended gallbladder) an alert is provided to the radiologist to consider a soft tissue mass obstruction. If a radiologist is present, these exams are prioritized in the radiologist worklist for urgent interpretation and reporting.

Considerations for Dataset Development

Procedures	{MRI abdomen with MRCP, MRCP, MRI Abdomen}
View(s)	{ thick-slab single-section sequence T2, T2 sequence, thin-section multisection sequence}
Age	[0,90]
Sex at Birth	{Male, Female}
Other	{pneumobilia, hemobilia, soft tissue mass anywhere in the biliary tree, susceptibility artifact from cholecystectomy clips, flow artifact, crossing vessel artifact, choldechocal cysts, biliary stricture, sclerosing cholangitis, hepaticojejunostomy/Whipple/etc}

Technical Specifications

Inputs

DICOM Study

Procedure	MRCP, MRI Abdomen with MRCP, MRI Abdomen
Views	thick-slab single -section sequence T2, T2 sequence, thin-section multisection sequence
Data Type	DICOM
Modality	MRI
Body Region	Abdomen
Anatomic Focus	Common bile duct and gallbladder

Primary Outputs

Common Bile Duct Stone Detection

RadElement ID	RDE1116
Definition	Detection of common bile duct stone
Data Type	Categorical
Value Set	Absent Present Undetermined
Units	N/A

Common Bile Duct Stone Size

RadElement ID	RDE1114
Definition	If a common bile duct stone(s) is present then determine maximum measurement
Data Type	Numeric
Value Set	N/A
Units	mm

Secondary Outputs

Common Bile Duct Dilation Measurement

RadElement ID	RDE1115
Definition	Biliary ductal dilation measurement
Data Type	Numeric
Value Set	N/A
Units	mm

Common Bile Duct Dilation Detection

RadElement ID	RDE1117
Definition	Biliary ductal dilation detection based on measurement. Absent if measurement is less than 6 mm for patients younger than 60 years, allow 1 mm for each decade over 60 years. Present if measurement is less than or equal 6-9 mm for patients younger than 60 years, allow 1 mm for each decade over 60 years. Present if measurement is greater than 15 mm in the setting of prior cholecystectomy.
Data Type	Categorical
Value Set	Absent Present Undetermined
Units	N/A

Periductal Fluid Detection

RadElement ID	RDE1118
Definition	Periductal fluid detection (high T2)
Data Type	Categorical
Value Set	Absent Present Undetermined
Units	N/A

Gallbladder Lumen Distention Measurement

RadElement ID	RDE1119
Definition	Gallbladder lumen distention (a measurement greater than 45 mm is considered distention)
Data Type	Numeric
Value Set	N/A
Units	mm

Future Development Ideas

In the case of biliary ductal dilatation without an identified stone or prior gallbladder/biliary surgery, soft tissue mass obstruction within the common bile duct, ampulla, or pancreas should be considered.
In the case of periductal fluid and ducal wall thickening or enhancement, perhaps cholangitis should be considered.
Consider adding the number of stones within the common bile duct if there are multiple in the future.

Related Datasets

No known related public datasets at this time, please alert us if you know of any.