Pneumobilia Detection on CT

Purpose	Detection of pneumobilia on CT
Tag(s)
Panel	Abdominal
Define-AI ID	22020020
Originator	Martha Menchaca
Lead	Martha Menchaca
Panel Chair	Luther B. Adair II
Panel Reviewers	Abdominal Panel
License	Creative Commons 4.0
Status	Public Comment
RadElement Set	RDES215

Clinical Implementation

Value Proposition

Identifying pneumobilia on CT.

AI for this use case would help in detecting, quantitating, comparing, and alerting both non-specialists and radiologists. In clinical settings where a radiologist is not readily available, such detection would be of value to non-radiologists such as technologists or ER physicians. 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.

Narrative(s)

A 70-year-old patient presents with abdominal pain to the emergency room at which time a CT scan is performed and branch-like hypodense areas are identified throughout the liver with a central predominance.

Workflow Description

The relevant images are obtained from the modality and sent to PACS and the AI engine based on anatomic landmarks. An algorithm evaluates the CT and, based on anatomic landmarks for the location of the liver, determines whether gas is present, absent, or indeterminate by assessing the Hounsfield Units. If present, it then assesses whether the gas is in the left hepatic lobe, absent in the left hepatic lobe, or indeterminate. For cases returned where the algorithm returns gas in the left hepatic lobe, the radiologist is made aware of the need for further evaluation. If the radiologist is not available, the non-radiologist provider is made aware of the need for further evaluation.

Considerations for Dataset Development

Procedures	{CT Abdomen with contrast, without contrast, CT Abdomen and pelvis}
View(s)	{Axial, Coronal, Sagittal}
Age	[0,90]
Sex at Birth	{Male, Female}
Catheter	{common bile duct stent, common bile duct drain}
Confounding Variables	{gas containing collection, portal venous gas, bowel loop interposed between liver and abdominal wall}

Technical Specifications

Inputs

DICOM Study

Procedure	CT Abdomen with contrast, CT Abdomen without contrast
Views	Axial, Coronal, Sagittal
Data Type	DICOM
Modality	CT
Body Region	Abdomen and Pelvis
Anatomic Focus	Liver, biliary system

Primary Outputs

Pneumobilia Detection

RadElement ID	RDE1392
Definition	Detection of Air in the Liver
Data Type	Categorical
Value Set	Absent Present Intermediate
Units	N/A

Secondary Outputs

Left Hepatic Lobe Gas

RadElement ID	RDE1393
Definition	Detection of Air in the Left Hepatic Lobe
Data Type	Categorical
Value Set	Absent Present Intermediate
Units	N/A

Future Development Ideas

Possible extension to this use case is to differentiate portal venous gas versus biliary gas (pneumobilia).