Dicom Header: Image Pixel

There is a set of attributes in the
dicom standard associated with the pixel bit representation in a dicom
image. Some image types (SOP classes) use the definitions in the Image
Pixel Module, others have specialized the image pixel attributes for
specifc to the SOP class (e.g. DX Image Pixel Module)

Here's the verbage for the general Pixel Module
Bits Allocated (0028,0100)
Number of bits allocated for each pixel sample. Each sample shall have
the same number of bits allocated. See PS 3.5 for further explanation.

Bits Stored (0028,0101)
Number of bits stored for each pixel sample. Each sample shall have the
same number of bits stored. See PS 3.5 for further explanation.

High Bit (0028,0102)
Most significant bit for pixel sample data. Each sample shall have the
same high bit. See PS 3.5 for further explanation.

Pixel Representation (0028,0103)
Data representation of the pixel samples. Each sample shall have the
same pixel representation. Enumerated Values: 0000H = unsigned integer,
0001H = 2's complement


For DX, the attributes have been specialized as follows
Bits Allocated (0028,0100)
Number of bits allocated for each pixel sample. Enumerated Values: 8,
16

Bits Stored (0028,0101)
Number of bits stored for each pixel sample. Enumerated Values: 6 to 16

High Bit (0028,0102) Most significant bit for pixel sample data. Shall
have an Enumerated Value of one less than the value in Bit Stored
(0028,0101).

Pixel Representation (0028,0103) Data representation of the pixel
samples. Shall have the Enumerated Value: 0000H = Unsigned Integer.

Plus there are several mandatory attributes describing the relationship
of the pixel values to the xray intensity values, rescaling factors,
etc which were applied during the processing.

Most DICOM viewers do handle data greater than 8 bits. CT and MR pixel
data are typically 12 bits, allocated into 16 bit words. I've seen CR
and DX at both 12 bits and 16 bits, and seen it displayed by numerous
applications.

However, picking up on our earlier conversation, I've seen a number of
DICOM acquisition gateways which only support capture 8-bit data. For
example you indicated your sensor manufacture had recommended
PACSGear. A quick browse of their website says they only support 8-bit
secondary capture. I don't know the detailed specs of acquisition
stations and so can't cite one off the top of my head which does
support capturing 16 bit data but am wondering if your problem is more
on constructing rather than displaying side of the equation. People
here are also usually pretty helpful to tell you what might be wrong if
you want to post one of your images to an accessible location

http://www.cabiatl.com/mricro/dicom/index.html

DICOM Sample
http://www.barre.nom.fr/medical/samples/
http://pubimage.hcuge.ch:8080/
ftp://medical.nema.org/MEDICAL/Dicom/DataSets/WG04
http://www.aycan.de/main/lp/sample_dicom_images.html
http://www.rubomed.com/dicomfiles/index.html

ftp://medical.nema.org/medical/dicom/DataSets/WG16 Enhanced MR product images
ftp://medical.nema.org/MEDICAL/Dicom/DataSets/WG12 Ultrasound product disk exchange test images
ftp://medical.nema.org/MEDICAL/Dicom/DataSets/WG04 Compression working group test images (uncompressed, JPEG, JPEG-LS and J2K

http://www.dclunie.com/medical-image-faq/html/part8.html