IMRT
Also written as: IMRT — Intensity-Modulated Radiation Therapy
Advanced radiation therapy technique that modulates beam intensity to spare normal tissues while targeting tumors.
Full Definition
Intensity-Modulated Radiation Therapy (IMRT) is an advanced form of external beam radiation therapy that uses computer-controlled linear accelerators to deliver precise radiation doses to tumors while minimizing exposure to surrounding healthy tissues. In head and neck oncology, IMRT is particularly valuable due to the complex anatomy and proximity of critical structures such as the parotid glands, spinal cord, and brainstem. The technique uses multiple beam angles and varying intensities within each beam to create highly conformal dose distributions. This allows for dose escalation to tumors while reducing toxicity to organs at risk.
Usage
Usage note: Distinguish from other advanced techniques like IGRT and VMAT.
In Context
- "IMRT planning achieved adequate target coverage while keeping parotid gland doses below tolerance." — Treatment planning report
- "The patient developed grade 2 xerostomia despite IMRT optimization for salivary gland sparing." — Follow-up assessment