Cholecystitis on CT

Purpose

To detect cholecystitis on CT

Tag(s)

 

Panel

Abdominal

Define-AI ID

19020003

Originator

Luther B. Adair, II Arun Krishnaraj

Panel Chair

Arun Krishnaraj

Panel Reviewers

Abdominal

License

Creative Commons
Status Public Comment
                               

Clinical Implementation


Value Proposition

Cholecystitis is a potentially life-threatening but readily treated emergency. AI meeting this use case would help in detecting, quantitating, comparing, 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 CT 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 cholecystitis on ultrasound and assess the need for further evaluation with CT.

Narrative(s)

A 40-year old patient presents with constant right upper quadrant pain and is taken to the emergency room at which time a CT scan is ordered. A 67-year old patient in the ICU with a history of diabetes presents with fever, but is intubated and is a poor candidate for an ultrasound. He is taken to the radiology department and a CT scan is performed.

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 gallstone, distention, or pericholecystic fluid.

An algorithm evaluates the CT scan and categorizes whether a gallstone is present, absent, or undetermined. If present, it then assesses whether pericholecystic fluid is present, absent, or undetermined; assesses whether the gallbladder is distended or not distended with a measurement. For cases returned where the algorithm returns a stone present, the recommendation for ultrasound is made and the ultrasound technologist is made aware. For cases returned where the algorithm returns a stone present, absent, or undetermined, but there are any secondary output elements (a distended gallbladder or present pericholecystic fluid) an alert is provided to the ordering physician to order an ultrasound. If a radiologist is present, the exam is prioritized in the radiologist worklist for urgent interpretation and reporting.

An algorithm evaluates the CT scan and categorizes a gallstone is absent, but pericholecystic fluid is present; determines that the gallbladder is distended. For cases returned where the algorithm returns a stone present, absent, or undetermined, but there are multiple secondary output elements (a distended gallbladder and present pericholecystic fluid) an alert is provided to the ordering physician to order an ultrasound. If a radiologist is present, the exam is prioritized in the radiologist’s worklist for urgent interpretation and reporting.

Considerations for Dataset Development


Procedures: {CT Abdomen, with contrast, without contrast, CT Abdomen and pelvis}

Views: {Axial, Coronal, Sagittal}

Age: [0,90]

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

Anatomic Focus

Gallbladder

Pharmaceutical


Scenario




Primary Outputs

Gallstone Detection

RadElement ID


Definition

Detection of gallstone

Data Type

Categorical

Value Set

0-gallstone absent

1- gallstone present

2-undetermined

Units

NA



Secondary Outputs

Pericholecystic Fluid Detection

RadElement ID


Definition

Pericholecystic fluid

Data Type

Categorical

Value Set

0-absent,

1-present

2-undetermined

Units

NA




Gallbladder Lumen Distention Measurement

RadElement ID


Definition

Gallbladder lumen distention

Data Type

Numeric

Value Set


Units


Future Development Ideas


  • gallstone location - although obstructive phenomena can be detected secondarily
  • corroborate CT and US data
  • provide ultrasound technologist with a statement of stone presence rapidly
  • Considering providing a scale of certainty based on findings which coincide with existing data to suggest a higher degree of sensitivity (i.e. presence of gallstone and sonographic murphy).