Contouring of Organs at Risk

Dr Rajesh BalakrishnanMD , DNB (Radiotherapy)

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References

• Radiotherapy and Oncology 93 (2009) 545–552• Radiotherapy and Oncology 110 (2014) 390-397

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Prerequisites

• Good Planning CT – Good Immobilistaion setup– With Contrast imaging– 3mm Slice thickness or smaller

• Suggested the center (HU) and width (HU) values (window settings) used to delineate the OARs– Brain: C35, W100– Bone: C450, W1,600– H&N: C35, W350– Parotid: C 840 , W 370

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• Temporal Lobes• Right Eye and Lens• Left eye and lens• Right Optic nerve• Left Optic nerve• Optic chiasm• Pituitary• Cochlea• Brainstem4

Organs at Risk (1)

• Spine• Parotid Glands• Sub Mandibular Gland• Pharyngeal Constrictors• Trachea• Brachial Plexus

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Organs at Risk (2)

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