Gamma Knife radiosurgery is a technique that uses intracranial stereotactic radiosurgery. It may be helpful in treating melanomas affecting the uvea, a part of the eye.
What is Gamma Knife radiosurgery for uveal melanoma?
Gamma Knife radiosurgery uses the administration of high dosages of radiation concentrated on targeting neoplasia, which is enriched in the back of the eyeball. To ensure maximum accuracy, it is necessary to immobilize the eye during the procedure.
How is Gamma Knife radiosurgery for uveal melanoma performed?
The patient is lightly sedated and then given a local anesthesia, where the stereotactic frame is placed and the eye surgeon, having instilled anesthesia into the eye, will fix stitches on the supporting structures of the eyeball, to ensure immobilization. The procedure is completely painless. After completing this step, the patient will be subjected to imaging tests (orbital MRI with gadolinium). The images will allow the specialist to plan for the most proper form of treatment. Once decided upon, the patient will lay with a stereotactic frame fixed on to the Gamma Knife bed. The treatment can last from one to six hours, depending on the needs of the patient and the target area for radiation.
What are the advantages to undergoing Gamma Knife radiosurgery for uveal melanoma?
Gamma Knife radiosurgery is a minimally invasive procedure , done in a single session and free of pain and surgical incisions. The procedure is almost always done on an outpatient basis and the patient is usually discharged the same day or the next.
Is Gamma Knife radiosurgery for uveal melanoma painful and / or dangerous?
The procedure is not painful, though the patient may feel pain during positioning of the four small metal pins to stabilize the helmet and mild burning while the eye is being treated. During the actual treatment, the patient will undergo subtle movements of the head, though they will not experience any pain or noises. The risks associated with this procedure may include worsening of visual impairment.
Which patients can undergo this procedure?
Patients with uveal melanoma can undergo this procedure. The eye doctor will confirm the indication for treatment, in collaboration with a neurosurgeon.
Follow up
The results of the procedure are not immediate . The patient will be informed of any additional examinations that need to be carried out during discharge. Usually, the patient will need to undergo an eye examination and magnetic resonance imaging of the orbits with gadolinium. Effects of the treatment can occur at a distance of at least three to six months.
What steps should be taken to help prepare for this procedure?
A few days before undergoing the procedure, the patient will travel to Humanitas for pre-admission and will be subjected to blood tests, an electrocardiogram (ECG), and a medical examination for a complete compilation of medical records. It is important that the patient announce any allergies to medications or contrast agents, or claustrophobia. On the day of the procedure, the patient should be accompanied by a family member or an acquaintance and should have been fasting from midnight the night before. On the night before the procedure, the patient should cleanse themselves with a product-based disinfectant shampoo, such as chlorhexidine. It is best to avoid wearing any jewelry: brooches, hairpins, makeup, hair products, and artificial nails; but rather wear comfortable clothing and footwear, preferably with buttons or zippers.
