Since Acquisition_Type needs to be imported into multiple schemas besides ToT.xsd and Tot.xsd needs to import these schemas, a circular reference can be omitted by making Acquisition its own schema. This will also permit extension of Acquisition_Type Referenced Instance Sequence (0008,114A) 1 Sequence of Items each providing a reference to an Instance that is part of the Series defined by Series Instance UID (0020,000E) in the enclosing Item. One or more Items shall be present PS 3.4-2008, C.6.1.1.5.1 Alternate Representation Sequence The Purpose of Reference Code Sequence (0040,A170), which shall describe the nature of the alternate encoding of the image. The Purpose of Reference Code Sequence (0040,A170) shall include only one Item. The Baseline Context Group for this Code Sequence is CID 7205. The Acquisition Number is a number produced by the instrument that is changed for each run. (the Acquisition Number is sequentially changed (incremented) for each run of the instrument independently of the measurement being performed) Depending upon the instrument, the underlying data-type and pattern can be changed without changing any code that includes this data-type. (0020,0012) Acquisition Number IS 1 The Instance Number is an integer that is increase by 1 for every set of binary data included in an ACS file. In order to maximize reliability, the values shall start with 1. this permits the last number to equal the total number of data sets. (0020,0013) Instance Number IS 1 It is suggested that the name of the file that contains the binary data includes either the Acquisition Number or the Instance Number. Tag=(0008,0022) Acquisition Date VR=DA 1 Tag =(0008,0032) Acquisition Time VR=TM 1 Acquisition Datetime (0008,002A) VR=DT Date and Time 1 The date and time that the acquisition of data that resulted in this image started. From: PS 3.3 - 2008, C.7.6.1 General Image Module Table C.7-9 specifies the Attributes that identify and describe an image within a particular series. Table C.7-9, GENERAL IMAGE MODULE ATTRIBUTES "Acquisition Number (0020,0012) A number identifying the single continuous gathering of data over a period of time that resulted in this image." This is also relevant to list-mode. (0020,0012) Acquisition Number IS 1 (