Periprosthetic Hip Lucency

Purpose

Measure periprosthetic lucency in the hip

Tag(s)

 #THA

Panel

 Musculoskeletal

TOUCH-AI ID

 TAI-05180009

Originator

 Munib Sana

Panel Chair

 Jay Patti

Panel Reviewers

 Musculoskeletal Panel

License

 Creative Commons 4.0

Status  Public Commenting

Clinical Implementation


Value Proposition

There are 400,000 total hip arthroplasties (THAs) performed annually. Every patient has annual follow-up exams, which can add up to about 100 reads per day for a musculoskeletal radiologist who works with arthroplasty surgeons. Aseptic loosening and adverse local tissue reaction complicate a significant number of THAs and necessitate revision arthroplasty. These are indolent processes that, if not detected early, can lead to osteolysis or extensive tissue necrosis. Findings are not readily apparent on x-ray and require comparison with multiple prior exams to see progression of abnormality over time. AI meeting this use case would help to reduce the false negative rate, patient risk, and medical legal risk for the radiologists. High-risk patients could be screened for elevated serum cobalt levels and sent to MRI for further evaluation. Delay in diagnosis could delay treatment for years.

Narrative(s)

A 65-year-old patient presents for annual follow-up THA x-ray. An algorithm evaluates the image and compares this exam with multiple prior exams, if accessible. The algorithm measures periprosthetic lucency. If the measurement is greater than 2 mm, the radiologist is alerted. Otherwise, the measurement displays when called.

Workflow Description

The current image and prior hip x-rays are analyzed by an AI engine. The engine measures periprosthetic lucency between the current image and images at least 5 years old or initial post-op film if THA was performed less than 5 years ago.

Considerations for Dataset Development


Procedures(s): X-ray, Hip

View(s): {AP, Frog-leg lateral, Cross-table lateral}

 

Sex at Birth: {Male, Female}

 

Osteolysis Location: {Gruen Zone 1, Gruen Zone 7, Gruen Zone 8, Gruen Zone 14}

 

Interval Between Imaging (years): [0,20]

 

Comorbidities: {Calcar resorption, osteoporosis, subsidence, lucency}

Technical Specifications


Inputs

DICOM Study

Procedure

XRAY, Hip

Views

AP, frog-leg lateral, cross-table lateral

Data Type

DICOM

Modality

XRAY

Body Region

Pelvis

Anatomic Focus

Hip

Primary Outputs

Periprosthetic Lucency

RadElement ID

RDE313

Definition

Measure periprosthetic lucency. Alert if greater than 2 mm.

Data Type

Numeric

Value Set

 

Units

mm

Secondary Outputs

Total Hip Arthroplasty Status

RadElement ID

RDE314

Definition

Status of the total hip arthroplasty

Data Type

Categorical

Value Set

0–Normal

1–Abnormal

2–Indeterminate

Units

N/A

Public Commenting


Use cases are meant to be a primary vehicle for distributing clinical information to the developer community. They pinpoint precise scenarios within radiology workflows where potential automation could add noticeable value and establish standards for interpreting and passing corresponding common data elements. Implementing effective standards requires the perspective from all stakeholders. So to that end, we encourage your feedback on use cases.

To submit comments, please email DSIUseCases@acr.org with the use case title(s) and relevant comments by January 1, 2019. If more convenient, you may also download this use case and comment directly on the PDF. Just attach the PDF copy on the email.