Aims and objectives
PACS migrations require element level data validation,
verification and cleansing,
mandating full knowledge of all elements within a closed set of DICOM files.
DesAcc’s processes enable the creation of a data dictionary and ontology specific to the hospital’s PACS environment and the establishment of a Data Lake with quantification of all elements and their associated enumerated values. The aim of this study was to see if the dictionary created could be used for identication of invalid...
Methods and materials
PACS data from a single site stored on tape,
MOD and spinning disc was used.
A subset containing 200,000 studies, MR (47%),
Ultrasound (19%) and X-Ray (1%) was used to for dictionary creation. 12,050,115 DICOM files containing 1,363,283,274 non-empty DICOM values were ingested.
Within the 1.3 billion DICOM values 29% were vendor specific ("Private Elements") and were excluded.
Of 2,500 elements defined within the 2017a DICOM Standard,
391 unique elements were identitified,
with 78 elements making up 75% of total values.
When value sets (the "ontology") for these 391 elements were generated,
for enumerated elements such as Body Part Examined,
over 50% of values were found to be illegal,
while misspellings in freeform elements such as Referring Physician Name (with...
Data Lakes can be utilised by hospitals for Business Intelligence,
quality improvement and outlier identification.
To create them,
it is necessary to build a data dictionary of all source elements and an ontology of their corresponding enumerated values. The PACS migration process offers the opportunity to build out a research Data Lake containing a de-identified copy of all migrated data. The ontology of terms collected on the closed set ofmigrated files provides a working set of identifying...
CEO DesAcc Inc.,
Managing Director DesAcc EMEA Ltd. Walter Balcavage,
Indiana University School of Medicine
NEMA PS3 / ISO 12052,
Digital Imaging and Communications in Medicine (DICOM) Standard,
National Electrical Manufacturers Association,
USA (available free at http://medical.nema.org/ )