Have been brushing up on anatomy... While many discussions document which fascia are the ones being interacted with during the procedure, I wanted to know where those fascia went as the tissue transitioned away from the penis...
Found these two images helpful
The right side highlights the volume accessible (if I'm reading it correctly) by this the typical
PMMA/
HA/
PCL filler
This is just another view, but under normal circumstances (i.e. not filled with urine)