This type of injury is difficult to diagnosis properly as it does not show up very well with typical CT scans of the head/brain. This is because the injury is more microscopic as opposed to macroscopic; thus, CT Scans, and MRI scans sometimes miss the injury. However, more modern tests are becoming available like MEG, and PET Scans. For example, there is Diffusion Tensor Imaging that is available to show the degree of white matter in the brain. The other tests can measure chemical flows in and out of the brain too. DAI also has delayed onset since it is primarily a biochemical deterioration. This is important for a lawyer handling a DAI case because he or she must be aware of this medical fact and consult with the doctors who are treating the patient. You have to be able to prove DAI in Court in order to establish the damages. due to the delayed onset is yet another reason why negative MRI and CT scans usually do not pick up the damage.