Unable to recruit any patients that fulfilled the narrow enrollment requirements

To confirm or refute recently published data regarding the reduction in post-stroke ischemic penumbra, that used SPECT/CT, by using the more precise tools of PET/MRI.

Most patients who suffer an acute ischemic stroke improve over the immediately ensuing 30-90 days. However, many patients do not improve beyond this initial period in spite of continued intensive physical therapy and supportive care. A prospective, randomized trial of the use of hyperbaric oxygen treatments in 59 such patients was published in January 2012. That study which used 40 hyperbaric oxygen treatments, indicated significant clinical neurological improvement in residual motor deficit in patients who had sustained a stroke over a year previously. An increase in brain activity in the region immediately surrounding their stroke (penumbra) was reported on the basis of SPECT studies. Regions of live cells were determined by CT. Because SPECT is primarily a measure of perfusion and not metabolic activity and CT is a poor measure of cell life, the investigators plan to assess areas of physiologic/anatomic mismatch in similar patients following hyperbaric oxygen treatment by the use of the more appropriate and precise tools, PET and MRI.

Inclusion Criteria:

• person must have sustained an acute ischemic stroke 6-12 months prior to enrollment, exhibited clinical improvement during the initial 30-90 days post stroke, exhibited no further improvement for at least 1 month in spite of continued supportive care and physical therapy, must have at least one residual measurable motor deficit.

Exclusion Criteria:

Smoking, Contraindications to an MRI e.g. pacemaker, Contraindications to hyperbaric oxygen treatment e.g. emphysema, claustrophobia. seizure disorder, Inability to tolerate pressurization e.g. Eustachian tube dysfunction, other uncontrolled co-morbidities e.g. diabetes, hypertension, thyroid disorders, renal or hepatic dysfunction.