The ACR in partnership with the Society of Nuclear Medicine and Molecular Imaging  has begun planning the future scope of the Dose Index Registry (DIR) Nuclear Medicine (Nuc Med) module.  


The purpose of the ACR DIR Nuc Med module is to document practice patterns and, over time, establish dose indices’ benchmarks for common nuclear medicine examinations.  Facilities can then compare their data to regional and national aggregate data to determine the potential for improvements.


Data Collected 

The DIR NM module currently only collects CT dose indices results for their facilities’ PET CT scans. The DIR NM module automatically de-identifies exam data sent directly to the registry to include Volume CT Dose Index (CTDIvol) and Dose Length Product (DLP). In addition, DIR CT also computes size-specific dose estimate values (SSDE), for body examinations, that more accurately represent the radiation dose absorbed by the patient, based on patient size. 


Exam descriptions are standardized using ACR Common radiology terms and semantic structures so that data are comparable across facilities and scanners.


Available Reports 

DIR NM participants can view CT dose indices results for their facilities’ PET CT scans in the DIR Standardized Reports. These are interactive reports that provide a variety of filters and other features for review of PET CT exams submitted to the registry.  For information about these reports, select a link to the articles below.


Several Knowledge Base articles are available to help you become familiar with reports.