Digital Imaging and Communications in Medicine (DICOM) is a standard for handling, storing, printing, and transmitting information in medical imaging. It includes a file format definition and a network communications protocol. The communication protocol is an application protocol that uses TCP/IP to communicate between systems. DICOM files can be exchanged between two entities that are capable of receiving image and patient data in DICOM format. DICOM enables the integration of scanners, servers, workstations, printers, and network hardware from multiple manufacturers into a picture archiving and communication system (PACS). The different devices come with DICOM conformance statements which clearly state the DICOM classes they support. DICOM has been widely adopted by hospitals and is making inroads in smaller applications like dentists' and doctors' offices.

1. DICOM Structure Basics Gunjan Patel MS - Medical software, BE-Biomedical Engineer PGD-Quality Management Email: gunjannpatel@gmail.com

2. Content History Introduction Why DICOM? DICOM Services Class Basic Terminology Exa.- RIS connection Uses of DIOCM 2

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6. Contin…. Need for Digital Image Generation More need for Digital Transfer/Archiving (PACS) More need for Post-Processing More need for Cross-Vendor Compatibility Need for Communication via Networks/Media 7

7. DICOM Services Class 8

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10. DICOM Terminology DICOM File Format Information Object Definition (IODs) Application Entity Title (AE Title) Service Class User/Provider (SCU/SCP) Unique IDentifier (UID) Transfer Syntax Value Representations (VR) 11

11. Attribute Name Tag Type Group Length (0002,0000) 1 File Meta Information Version (0002,0001) 1 Media Storage SOP Class UID (0002,0002) 1 Media Storage SOP Instance UID (0002,0003) 1 Transfer Syntax UID (0002,0010) 1 Implementation Class UID (0002,0012) 1 Implementation Version Name (0002,0013) 3 Source Application Entity Title (0002,0016) 3 Private Information Creator UID (0002,0100) 3 Private Information (0002,0102) 1C DICOM File Format File Preamble 128 Bytes (set to 00H by default) DICOM File Meta Information DICOM Prefix DICM File Meta Eléments ONE DICOM SOP Instance as sent during network transfer DICOM Data Set Group 0002H elements are alwaysencoded in Explicit VR LittleEndian DICOM File Format (Ref: PS 3.10, Sec.7.1) A DICOM Image File is more than an image stored in a File 12

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14. Modules may be specific (e.g. CT Image)The atomic piece of information in DICOM - Contains the actual information 14

15. “ I am sending a CT Image to you “ A verb (an action) A noun (an object) Service IOD DICOM Service and IOD Real world: DICOM: 15

16. Application Entity Title (AE Title) AE is essentially the name of a DICOM device or program used to uniquely identify it (you cannot have two identical AEs in your PACS network) Even though DICOM does not have strict requirements for AE naming, AEs are typically labeled with numbers and uppercase characters only – no spaces, punctuation signs, or other characters. In fact, it is not uncommon to see DICOM units that would accept only uppercase alphanumeric AEs. 16

17. Application Entity Title (AE Title) 17 John Tom , I am “ Hi . Can I send you a CT Image?“ Communicator’s Names AE Title(s) An AE Title must be UNIQUE on a given network

18. John Tom , I am “ Hi . Can I send you a CT Image?“ Communication Initiator Name Communication Recipient Name Calling AE Title / Called AE Title CallingAE Title CalledAE Title 18

19. “ am sending a CT Image to I you “ User Provider Service Class User/Provider (SCU/SCP) SCP SCU ServiceClass User role Service Class Provider role SCU’s are initiating the actions. Therefore, they are usually initiating the communication (i.e. the association) 19

22. Query/Retrieve

23. Modality Worklist20

25. A UID is a string of up to 64 Characters including digit numbers (“0” to “9”) and “.” e.g. SOP Instance UID= 1.2.840.113619.2.65.3.200583648570.2428.1178103577.1

27. A SOP Instance UID of an image shall never be equal to the SOP Instance UID of another image

28. An Image SOP Instance UID shall never be equal to a Series Instance UID21

32. Value Representations (VR) Clinical data comes in a wide variety of formats. Ex. Distances measured in millimeters, time in seconds, patient names are typically written in alpha-betic characters, and so on. The DICOM standard defnes 27 basic data types, known as value representations (VRs), which are designed to encapsulate all possible clinical data types. Each VR has its own abbreviated two-letter name, a defnition of what it represents, a description of what characters are allowed in its data, and a pre-scribed data length. 25

34. DA: Date

35. TM: Time

36. DT: DateTime

37. PN: Person Name

38. Other VR:

39. OB: Other Byte

40. OW: Other Word

41. OF: Other Float

42. SQ: Sequence

43. …

44. Free Form Text VR:

45. SH: Short String

46. LO: Long String

47. ST: Short Text

48. LT: Long Text

49. UT: Unlimited Text

50. Math VR:

51. IS: Integer String

52. DS: Decimal String

53. US: Unsigned Short

54. SS: Signed Short

55. UL: Unsigned Long

56. SL: Signed Long26

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62. A lot of flexibility to support all features available on various vendor’s printers31

63. MEDICAL DIRECTORY DICOM for Media Interchange The DICOM Directory (a.k.a. DICOMDIR) facilitates media browsing The same image objects as defined for Network exchange are usable on physical media ALL DICOM INFORMATION OBJECTS DICOM File Format ISO 9660 UDF FAT 16 FS ISO 9660 Level 1 DOS DOS 130 mmMOD (650 MB, 1.2, 2.3, 4.1GB) 90 mm MOD (128, 230, 540, 640 MB, 1.3, 2.3 GB) DVD-ROM -R/+R/-RW/+RW CD-ROMCD-R USBMedia DICOM Relies on Broadly Available Media Storage Technology 32

64. Uses of DIOCM 33

65. Feedback and Query ??? 34

66. “Save Paper, Save Earth, Save US” Thank you !!! Email : gunjannpatel@gmail.com www.bmeportal.ning.com 35

67. Referances DICOM Cook Book -for Implementations in Modalities Digital Imaging and Communication in Medicine (DICOM)- OS Priyankh http://www.mediacy.com/index.aspx?page=IQDICOM_Service http://medical.nema.org/ 36