Table 2 Key features of each subtype of parasagittal central hypoxic–ischaemic injury
Mild | Moderate | Severe | Massive paramedian | |
|---|---|---|---|---|
Parasagittal structures affected | Sensorimotor cortex | Sensorimotor cortex, SMA | Sensorimotor cortex, SMA and more of the PCL | Sensorimotor cortex, SMA, PCL, extending to the SFG and SPL |
Boundaries of the injury | Limited to perirolandic cortex only | Perirolandic cortex and anterior part of the PCL | Perirolandic cortex and PCL | Laterally to edge of central sulcus, anteriorly and posteriorly to the edges of the IHF |
White matter destruction | Nil | Some reduction in WM volume | Slightly more WM volume reduction | Severe decrease in overall WM volume |
Interhemispheric fissure widening | Apposed paramedian gyri | Slight widening of the fissure at the PCL | Inverted V-shaped opening of the fissure | Diamond-shaped widening of the fissure |
Central cortico-spinal tract destruction | Usually none or minimal along the long tract | Mild hyperintensity along the long tracts | More significant destruction of the central WM tracts | Near complete destruction |
Insular Cortex | Spared | Minimally involved | Moderately involved | Near complete destruction |
Mammillary Bodies | Usually spared | Mildly injured | Moderately injured | Severely atrophied |
Heschl Gyrus | Usually spared | Mildly injured | Moderately injured | Severely injured |
Hippocampi | May be slightly decreased in volume | Moderately decreased in volume | Severely decreased in volume | Complete destruction |
Calcarine cortex | Usually, normal | Mild signal change | Moderate signal change | Significant signal change and atrophy |
Corpus callosum | Mild central CC atrophy | Moderate central CC atrophy | Marked central CC atrophy | Near complete central CC atrophy |
BGT involvement | Mild signal change | Moderate signal change up to less than 50% volume involved | Marked signal change greater than 50% volume involved | Spongiotic cavitation at putamen and thalami |