Stereotactic Radiosurgery

Stereotactic Radiosurgery (SRS) & Stereotactic Body Radiotherapy (SBRT)

Overview

Stereotactic Radiosurgery (SRS) is a non-surgical radiation therapy used for treating small tumors and functional disorders of the brain with high precision. Stereotactic Body Radiotherapy (SBRT) applies similar techniques to treat tumors in the body.

These outpatient procedures use precisely targeted radiation in high doses to spare healthy tissue.

What Is Stereotactic Radiosurgery?

SRS is a minimally invasive radiation treatment that targets brain, spine, and body tumors or abnormalities. Unlike surgery, there is no physical removal of the tumor. Instead, concentrated radiation beams damage DNA in cancer cells, making them unable to reproduce.

SBRT is used for body tumors, where radiation is carefully directed at the tumor while keeping the patient immobile.

How It Works

SRS and SBRT rely on advanced technologies:

3D imaging (CT, MRI, PET/CT) to locate tumors
Patient immobilization systems
Gamma-ray or X-ray beams that converge precisely
Image-Guided Radiation Therapy (IGRT) to enhance targeting

Fractionated Stereotactic Radiotherapy (SRT) is used when:

The tumor is larger than 1 inch
Treatment needs to be split into 2–5 sessions for safety

Diseases Treated

Brain Conditions:

Benign & malignant tumors
Primary or metastatic tumors
Tumors at the skull base or orbital regions
Arteriovenous malformations (AVMs)
Trigeminal neuralgia
Tremors and neurological disorders

Body Conditions (SBRT):

Lung cancer
Liver tumors
Abdominal tumors
Spinal tumors
Prostate cancer
Head & neck tumors

Types of Equipment Used

Gamma Knife Radiosurgery:
- 192–201 focused gamma rays
- Ideal for small to medium intracranial lesions
LINAC Radiosurgery:
- Uses high-energy X-rays (photons)
- Suitable for larger or multiple-session tumors
Proton Beam Radiosurgery:
- Uses protons or neutrons
- Best for small, irregular tumors

Benefits of SRS

High radiation dose to the target with minimal damage to nearby tissues
Reaches hard-to-access brain areas
Non-invasive: fewer complications, less post-op discomfort
Quick recovery: often same-day or overnight stay
Often performed under local anesthesia (general for children or certain adults)

Aftercare & Side Effects

Recovery:

Resume normal activities in 1–2 days
Possible side effects: headache, nausea, pin-site bleeding

Common Side Effects:

Fatigue
Skin issues (redness, itching, dryness)
Hair loss (only in treated areas)
Mouth & swallowing problems
Nausea, diarrhea, digestive discomfort
Urinary or bladder changes

Long-Term Risk:

Small risk of developing new cancer from radiation

FAQs

Q: What is the difference between SRS and traditional radiotherapy?
A: SRS delivers high doses with pinpoint accuracy, exposing minimal normal tissue.

Q: How often can you receive SRS?
A: Usually between 1–8 treatments depending on tumor size and location.

Q: Will I lose hair with SRS?
A: Only if the treatment area is near the scalp. Hair loss is generally temporary.

Q: What to expect after SRS?
A: Minor bleeding or pain at pin sites, potential headaches or nausea, managed with medication.

Q: What does "stereotactic" mean?
A: A method that uses 3D coordinates from imaging to guide radiation or surgical instruments to precise locations in the body.