The User Information Item shall be made of a sequence of mandatory length fields followed by a variable field. Table 9-20 shows the sequence of the mandatory fields.
The variable field shall consist of one or more User-Data Sub-Items.
Note: The User-Data Sub-Items may be present in any order within the User-Information Item. No significance should be placed on the order of User-Data Sub-Items within the User Information Item. Sending applications should be aware that some older applications might expect Sub-Items to be encoded in ascending order of Item-type within the enclosing Item.
Table 9-20 USER INFORMATION ITEM FIELDS
|Item bytes||Field name||Description of field|
|2||Reserved||This reserved field shall be sent with a value 00H but not tested to this value when received.|
|3-4||Item-length||This Item-length shall be the number of bytes from the first byte of the following field to the last byte of the User-data-information field(s). It shall be encoded as an unsigned binary number.|
|5-xxx||User-data||This variable field shall contain User-data sub-items as defined by the DICOM Application Entity. The structure and content of these sub-items is defined in Annex D.|