@mmaryemc
Below is a response I just now received from my Neurophysiology friend in London. I was hoping for better news but here is her response.

Hi Jake
Lovely to hear from you. All OK here. Well, OK being crazy, with an American/Irish house with two small children and one about to arrive! It's a blessing 😀

Whilst a PET scan does indicate glucose uptake, i strongly doubt it would be helpful in this case. The PET scanning technique has been around for years and if this was an identified clinical use it would be mainstream.

The scan basically demonstrates "hotpots" of metabolism, therefore indicates which body parts or specific areas are using more glucose than others. This is very useful in detecting cancers/lesions if a patient is suspected of having secondary /metastatic spread, or to source the primary tumour if a scan elsewhere has found evidence of cancer spread, for example.

The brain as a whole uses more glucose than any other body part, relatively, I'd go as far to say doing a scan in this situation would be pointless as it's only demonstrating "relative" increased uptake and the brain even in coma will demonstrate higher metabolism than anywhere else. There would be no predictability value attached to those results as they would not be specific.

The fact she's having seizures would imply that there is still a good deal of metabolism in order to generate the brain activity required to make seizures happen.
This though doesn't have any bearing or implication regarding prognosis and doesn't in any way help quantify the amount of remaining "useful" brain activity.

I'm ever so sorry to not be the bearer of hopeful news. Coma is a tortuous condition both for the patient and their families. We know some people can undergo a mild drug induced coma to let the body rest and this helps, and we know sometimes the body does this itself. There's no limit on how long a person can stay in that state, we know people spontaneously can recover to one degree or another and we know sometimes they just don't. It's totally unpredictable.
I wish I could give more positive news or information but I think it's important to be honest and straight.
I'll keep you, and this family, in my thoughts and prayers xx
Anna / Jake

@mmaryemc - wanted to check in with you on your 14-year-old granddaughter who was put into a medically-induced coma due to her seizures and the physician's concern about brain damage. Has she awakened? Is she now in a rehab facility?

Also wondering how you are doing with all of this?