Basic Treatment Planning

Optic chiasm homogeneity

• Excessive dose to optic chiasm risks optic neuropathy, potential loss of sight, blindness

Clinical Scenario: • Pituitary Tumour, prescribed dose 50 Gy in 25 fractions • Maximum dose to optic chiasm 55 Gy • QUANTEC 55Gy <3% risk of optic neuropathy  ‘safe’?