Sunday, December 6, 2009

Cyber Knife Radio surgery in Pediatric Patients

Cyber Knife Radio surgery in Pediatric Patients

Dr.R.Rathna Devi, Sr. Consultant Radiation Oncologist

One little girl told me “ I want to go to school” she was one of my early pediatric patient with AVM for the new facility, Cyber Knife. That’s what was on her mind. And that’s what she did. She went to school immediately after her treatment. This made a tremendous difference to the family and to the child, and I was very happy to have offered her this”.

Cyber Knife radio surgery has a great advantage in treatment of pediatric intra and extra cranial lesions which includes non – invasive immobilization, low radiotherapy exposure to the developing normal brain other tissues and ability to fractionate the treatment.

Young patients in the past were usually required to wear a of head frame (Gamma Knife, other kind of radiosurgery equipments), and had to remain anesthetized during the entire, often day long procedure.

These procedures uses rigid metal frame attached directly to the patient’s skull to orient the radiation beams, making it difficult to treat young children with small/ fragile heads. Because the frame cannot be removed between the initial imaging and subsequent treatment, doctors also had to work fast with the other types of radio surgery. With the clock ticking, we had to place the frame, perform CT/MRI or other imaging studies; get everyone involved to meet, plan the treatment and then treat the patient, while the patient is intubated and asleep. This is not an optimal situation.

Fortunately now at Apollo Speciality Hospital we can treat young patients (who can hop off the table and go home or to school) after the initial imaging step while we plan the treatment strategy. The non invasive process uses tiny focused beams of radiation to perform radio surgery on a patients head or body. This technique allows us (Doctors) to attack trouble spots deep within the brain while minimizing the dose of radiation to surrounding healthy tissue. This is particularly important in children, whose brain is still developing.


Cyberknife which was developed by John Adler, uses a mesh mask to stabilize the head. The technology tracks any unintentional movement on the part of the patient and adjusts the radiation path as necessary. Children who can understand the importance of holding still can undergo the treatment while conscious, younger kids can have short term anesthesia for approximately hour – long diagnostic and treatment session. The recovery from anesthesia is usually quicker because they don’t usually have to be intubated.

At Apollo specialty hospital, till date we had the opportunity to treat 11 children with Cyberknife radio surgery. Our first Cyberknife patient was a pediatric patient with cervico medullary haemangioblastoma 15 years male patient from Tripura . He presented with neck pain, poor cough reflex, and difficulty in swallowing and upper limb tingling sensation. Investigations revealed cervico medullary expansile lesion involving medulla to C2 C3 level.

He underwent occipito cervical craniotomy and decompression, because of high vascularity, surgery was abandoned. He underwent Cyberknife radio surgery between 24th to 26th March 2009. In the first follow up after 3 months, his symptoms completely disappeared follow up MRI showed reduction in size of lesion and contrast enhancing portion of the lesion reduced significantly.

This boy really benefited out of Cyberknife radio surgery. Treating only the affected area with out affecting adjacent brain tissue. He is due for his 10th Std board exam now.


We have treated 4 patients with AVM, and other treated indications include :

1 patient with Supracellular Hemartoma

1 patient with pineliocytoma

1 patient with Recurrent Meningioma

1 patient with Brainstem Glioma

1 patient with Pilocytic astrocytoma (residual)


1 patient with vertebral Haemangioma

To conclude, Cyberknife: represents an entirely new approach to radiosurgery. It is the only system that combines robotics, and advanced image guidance to deliver frameless radio surgery.

Cyberknife features robotic arm and proprietary image guided technology. The robotic arm is computer controlled and has an arm movement precision of 0.5mm.

Greatest advantage is an out patient basis treatment.