Figure 1.

Peri-lesional hyperglycolysis in the absence of cerebral ischaemia. CT, CBF, CMRO₂, OEF, and ¹⁸F-FDG kinetic parameters obtained in a 29-year-old male within 24 h of severe TBI following a road traffic accident. Plasma glucose during imaging was 6.6 mmol/l. (A) CT demonstrates bilateral temporal and parietal haemorrhagic contusions. Regions of interest are defined for haemorrhagic lesion (core, red), hypodense tissue (penumbra, blue), and a 1 cm border zone of normal-appearing tissue (peri-penumbra, green). (B) Co-registered parametric maps of CBF, CMRO₂, OEF, K₁, K_i and k₃. The regions with a critical increase in OEF above the individually calculated threshold (ischaemic brain volume) and region of increased phosphorylation activity (k₃ hotspot) are both shown in red overlying the CT scan. The ischaemic brain and k₃ hotspot volumes were 7 ml and 56 ml, respectively, and overlap between these two tissue classes in this patient was 0.4 ml.