Stereotactic radiosurgery (SRS) is a non-invasive therapeutic procedure that delivers high-dose ionizing radiation to a precisely defined intracranial target with sub-millimeter accuracy, typically in one to five fractions.

Unlike conventional radiotherapy, SRS relies on:

• Stereotactic localization systems (frame-based or frameless)
• Advanced imaging techniques (CT, MRI, PET)
• Steep dose gradients to spare surrounding healthy tissue

SRS is most commonly used for:

• Brain metastases
• Arteriovenous malformations (AVMs)
• Vestibular schwannomas
• Meningiomas
• Functional disorders (e.g., trigeminal neuralgia)

Despite the term “surgery,” no incision is made. The “surgical” aspect refers to the precision and therapeutic intent, akin to resection.

• Single-session (classic SRS) vs. Hypofractionated stereotactic radiotherapy (HSRT)
• Delivered using systems such as Gamma Knife, CyberKnife, or LINAC-based platforms

Clinical goal: Maximize tumor control or lesion ablation while minimizing damage to adjacent critical structures.