gamma_knife_radiosurgery

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
gamma_knife_radiosurgery [2025/05/15 19:24] – administradorgamma_knife_radiosurgery [2025/05/15 19:26] (current) – [Indications] administrador
Line 26: Line 26:
  
 [[Gamma Knife radiosurgery Indications]]. [[Gamma Knife radiosurgery Indications]].
 +
 +====== Gamma Knife Radiosurgery (GKRS) Modalities ======
 +
 +Gamma Knife Radiosurgery (GKRS) is a form of stereotactic radiosurgery used to deliver highly focused radiation to intracranial targets. Below is a classification of the main modalities used in GKRS.
 +
 +===== 1. Based on Treatment Delivery =====
 +
 +==== a. Single-Fraction SRS ====
 +  * **Definition:** Entire dose delivered in one session.
 +  * **Indications:** Small brain metastases, vestibular schwannomas, trigeminal neuralgia.
 +  * **Advantages:** Quick procedure, high precision, minimal invasiveness.
 +
 +==== b. Hypofractionated SRS (HF-GKRS) ====
 +  * **Definition:** Radiation delivered over 2–5 sessions.
 +  * **Indications:** Large tumors, lesions near eloquent brain areas (e.g., optic pathways, brainstem).
 +  * **Advantages:** Reduces risk of radiation necrosis in sensitive structures.
 +
 +===== 2. Based on Gamma Knife Platform =====
 +
 +==== a. Gamma Knife Perfexion ====
 +  * Modular collimator system.
 +  * Allows automated repositioning.
 +  * High efficiency and precision.
 +
 +==== b. Gamma Knife Icon ====
 +  * Includes cone-beam CT for adaptive planning.
 +  * Enables frameless mask-based immobilization.
 +  * Allows for hypofractionation.
 +  * Real-time motion monitoring.
 +
 +==== c. Older Models (4C, B, C) ====
 +  * Rely on rigid frame-based fixation.
 +  * Longer preparation time.
 +  * No fractionation capabilities.
 +
 +===== 3. Based on Immobilization Method =====
 +
 +==== a. Frame-Based Fixation ====
 +  * Titanium stereotactic frame fixed to skull.
 +  * Maximum precision.
 +  * Preferred for functional and AVM cases.
 +
 +==== b. Frameless Fixation (Mask-Based) ====
 +  * Thermoplastic mask with image guidance.
 +  * Available in Gamma Knife Icon only.
 +  * Enables outpatient workflow and multiple sessions.
 +
 +===== 4. Based on Target Type =====
 +
 +==== a. Tumoral ====
 +  * Examples: Brain metastases, meningiomas, gliomas.
 +  * Dose and fractionation depend on size, location, histology.
 +
 +==== b. Vascular ====
 +  * Example: Arteriovenous malformations (AVMs).
 +  * Dose: 16–25 Gy.
 +  * Gradual obliteration over 2–3 years.
 +
 +==== c. Functional ====
 +  * Examples: Trigeminal neuralgia, tremor, epilepsy.
 +  * Very high precision required (e.g., 90 Gy for trigeminal root entry).
 +
 +===== 5. Summary Table =====
 +
 +^ Modality                    ^ Platform              ^ Fixation       ^ Dose Scheme         ^ Typical Indications                     ^
 +| Single-fraction GKRS       | All                   | Frame or mask  | 1 session (18–25 Gy) | Small metastases, schwannomas           |
 +| Hypofractionated GKRS      | Icon only             | Mask           | 3–5 sessions         | Large tumors, near critical structures  |
 +| Functional GKRS            | All (prefer frame)    | Frame           | 1 session (up to 90 Gy) | Trigeminal neuralgia, essential tremor  |
 +| AVM GKRS                   | All                   | Frame           | 1 session (20–25 Gy) | AVMs not suitable for surgery           |
 +
 +
  
  
  • gamma_knife_radiosurgery.txt
  • Last modified: 2025/05/15 19:26
  • by administrador