Coverage of the target volume: cribriform plate
- To include the cribriform fossa
in the CTV and allowing an
additional appropriate margin
to the PTV, the PTV frequently
includes the lenses.
- We consider it necessary to
frequently deliver a higher dose
to the lens (accepting an
increased
probability
of later
cataract development) than not
adequately cover the cribriform
plate.
- SFOP group suggested that the
edge of the shielding block/
MLCs is
at least 5 mm below
the cribriform fossa
as this
field edge definition is not
associated with an increase risk
of frontal recurrence