Have you checked if the "Instance Number" element (tag: 0020,0013) contains the information that you require?

When I use my DICOM viewer I can see the information (thanks Olaf and Waldemar) . Both Image number and tag: 0029,0013 contain that info however when I read the image in my matlab code and use dicominfo command that info is not included.

Tag (0029,0013) indicates a "private date element", i.e. a data element defined by an implementor, which is not contained in the DICOM standard. Citing from the DICOM standard:

"Private Data Elements have an odd Group Number that is not (0001,eeee), (0003,eeee), (0005,eeee), (0007,eeee), or (FFFF,eeee)." Details are discussed in section 7.8 of the standard (part 5, referenced below).

Are private data elements fully supported by your matlab code?

http://dicom.nema.org/medical/dicom/current/output/pdf/part05.pdf

http://dicom.nema.org/standard.html

 When you use the matlab routine dicomdisp(file) you will get all (present) dicom tags. The images number is stored in (0020.0012) - in (0020.0013) there is an instance number.

(0020,0012) is Acquisition Number, not Image Number (see "http://dicom.nema.org/medical/dicom/current/output/chtml/part03/sect_C.7.6.html#para_60848ddb-641c-4c4e-a059-f329100ef248").

(0020,0013) used to be called Image Number but we changed it in CP 99 to Instance Number when we were considering how to store (and query for) more things than just images (see "http://dicom.nema.org/medical/dicom/current/output/chtml/part03/sect_C.7.6.html#para_bcd1b0e0-3a37-45bc-b41a-7f49d7633ffd" and "ftp://medical.nema.org/medical/dicom/final/cp099_ft.pdf").

David

In Matlab,

info_img = dicominfo('*.dcm');

InstanceNumber = info_img.InstanceNumber;

img_number = InstanceNumber;

For a lot of information ,you can check the following link:

https://stackoverflow.com/questions/20556897/how-to-find-number-of-images-in-a-dicom-study

For matlab , you can write :

help dicominfo

With Matlab use this instruction:

Dicominfo