What is MRgFUS ?
Imagine your doctor being able to see inside your body, find your tumor and treat it without incisions . This is the idea behind a procedure called Magnetic resonance guided focused ultrasound .
MRgFUS uses a combination of high intensity ultrasound waves and magnetic resonance imaging to provide a novel treatment alternative for tumors .MRgFUS focuses the ultrasound energy to a small spot about the size of a peanut inside the tumors. MRgFUS focuses the ultrasound energy to a small spot about the size of a peanut inside the tumor and heats that spot sufficiently to cause cell death .
During treatment , Magnetic resonance images enable the physician to “see” the tumor and surrounding organ in 3 D , obtain real time feedback about temperature changes in the treated areas , and observe what has been treated , in a totally non -invasive manner .
The first investigations of HIFU for non-invasive ablation were reported by Lynn et al. in the early 1940s. Extensive important early work was performed in the 1950s and 1960s by William Fry and Francis Fry at the University of Illinois and Carl Townsend, Howard White and George Gardner at the Interscience Research Institute of Champaign, Ill., culminating in clinical treatments of neurological disorders. In particular High Intensity ultrasound and ultrasound visualization was accomplished stereotaxically with a Cincinnati precision milling machine to perform accurate ablation of brain tumors. Until recently, clinical trials of HIFU for ablation were few (although significant work in hyperthermia was performed with ultrasonic heating), perhaps due to the complexity of the treatments and the difficulty of targeting the beam noninvasively. With recent advances in medical imaging and ultrasound technology, interest in HIFU ablation of tumors has increased.
The first commercial HIFU machine, called the Sonablate 200, was developed by the American company Focus Surgery, Inc. (Milipitas, CA) and launched in Europe in 1994 after receiving CE approval, bringing a first medical validation of the technology for benign prostatic hyperplasia (BPH). Comprehensive studies by practitioners at more than one site using the device demonstrated clinical efficacy for the destruction of prostatic tissue without loss of blood or long term side effects. Later studies on localized prostate cancer by Murat and colleagues at the Edouard Herriot Hospital in Lyon in 2006 showed that after treatment with the Ablatherm (EDAP TMS, Lyon, France), progression-free survival rates are very high for low- and intermediate- risk patients with recurrent prostate cancer (70% and 50% respectively) HIFU treatment of prostate cancer is currentlyan approved therapy in Europe[, Canada, South Korea, Australia, and elsewhere.As of 2012, clinical trials for the Sonablate 500 in the United States are ongoing for prostate cancer patients and those who have experienced radiation failure.
Use of magnetic resonance-guided focused ultrasound was first cited and patented in 1992. The technology was later transferred to InsighTec in Haifa Israel in 1998. The InsighTec ExAblate 2000 was the first MRgFUS system to obtain FDA market approval in the United States.
What are the advantages of MRgFUS?
MRgFUS is a procedure designed to reduce your tumor related symptoms , resulting in significant improvement in your qualityof life . It is a non invasive alternavtive to surgery or hormonal treatments . Only over night hospital stay is required and most patients are able to return to everyday life the very next day .
During the procedure , you lie on your back or tummy , on the MRgFUS table inside MRI scanner . Conscious Sedation or rarely anesthesia is given to help you relax . You are awake throughout the procedure and your doctor communicates with you during the treatment .
First the doctor obtains MR images and uses these to see the exact location ans size of your tumor and to plan your treatment . Then individual pulses of focused ultrasound energy , called soncations each lasting about 20 seconds are used to heat the lesion , one planned spot at a time, until your doctor is satisfied with the treatment . Afterwards , MR images with contrast are taken to determine how effective the treatment was .
What happens to the patient after the procedure?
Following the treatment , patients will generally require 1-2 hrs of rest while the conscious sedation wears off . you may experience some abdominal pain , cramping or nausea. If necessary , your doctor will provide instructions for medication to keep you comfortable upon discharge . Usually , only over the counter pain relief medication is required . Most patients are able to return to work and normal activity the next day .
what are the risks of the treatment ?
As with any medical procedure , there are risks involved with the MRgFUS treatment .These risks could include back or leg pain , mild skin burns ,abdominal cramping, nausea , fever , vaginal discharge , and urinary tract infection . The incidence of these complications is relatively low .
Who is the right patient for MRgFUS?
Your physician will help you decide if you are a candidate . Baseline MRI with contrast study is done on every patient to determine if they are a candidate for the procedure .
Where can we use MR -Guided Focused Ultrasound surgery ?
Utrerine Fibroids : 25-30% of Indian female patients suffer from Uterine Fibroids . These patients have symptoms like heavily bleeding , abdominal pain, increased urinary frequency , constipation and infertility . MRgFUS is FDA approved modality for treatment of these uterine fibroids . Jaslok hospital is the only centre in India where this modality is available .
Adenomyosis : Patients suffer from heavy bleeding , abdominal pain and infertility due to adenomyosis . MRgFUS is a CE approved modality for treatment of focal Adinomyosis.
Bone Metastasis : Excruciating pain is the main symptom in patients with bone metastasis. MRgFUS helps us to achieve : a) pain palliation b) local tumor control c) skeletal stabilization .
Prostate Cancer : Patients with T1- T2 tumors ( low and intermediate risk) are ideal candidates for treatment with MRgFUS .
Future applications :
liver / brain tumors : Research work is going on for treatment of liver and brain tumors with MRgFUS.
Functional brain surgery : Research work is on to perform MRgFUS in functional brain surgery like STN etc . Increase drug response to cancer , osteoporosis, Arthritis , Thrombolysis, Embolisation of tumors