MR guided Focussed Ultrasound Surgery

Dr Shrinivas Desai, Head of Imaging, Jaslok Hospital explains the benefits of MrgFUS and HIFU in treating uterine fibroids and more

MR guided Focussed Ultrasound Surgery is a revolutionary non-invasive, procedure which uses high doses of focussed ultrasound waves (HIFU) to treat different tumours inside the body without surgery. MRgFUS machine consists of a combination of an MRI scanner and HIFU transducer. MRI localises the lesion and guide the HIFU beam to destroy the target tissue safely and accurately with submillimetre precision.

The HIFU transducer focusses sound energy on the area to be treated and destroys the abnormal cells. Imagine using a magnifying glass to focus the sun’s energy on a single point to burn a leaf or paper. The focussed ultrasound energy is directed at a small volume of tumour raising its temperature high enough to cause thermal ablation (killing of the cells) without impacting other tissues. Pulses of energy are repeated until the entire volume is treated.

Following the treatment post contrast MRI images allow the Radiologist to confirm that the treatment is completed. The body gradually removes the treated tissue over a period of months after the treatment.

MRgFUS was installed in Jaslok Hospital in May 2010. Since its inception, we have treated more than 710 patients, covering more than 1600 different lesions.

Clinical applications of MRgFUS

1. Uterine Fibroids and Adenomyosis
2. Facetal arthropathy
3. Bone metastasis
4. Primary Bone Tumour
5. Prostate cancer

Upcoming applications

1. Breast cancer
2. Brain tumours
3. Movement disorders (Intentional Tremor/ persistent Parkinsonism)
4. Epilepsy
5. Liver tumours

Uterine fibroids

In October 2004, FDA approved the use of MRgFUS for the treatment of uterine fibroids. MRgFUS offers a non-invasive alternative to hysterectomy or myomectomy.

During the procedure the patient lies on her stomach on MRI table HIFU is underneath the table.

Afterwhich the patient is given a mild sedative and pain medication for relaxation. it is important to note that the  patient is conscious and awake during the treatment.

Fibroid is treated with high intensity sound waves and destroyed by Thermal Ablation. There is irreversible death of tumour cells if it is heated at temperature of 75 to 90 degree centigrade. MR thermometry has a unique capability to measure the temperatures online at any given point right from the skin to the tumour.

During treatment, it is normal to feel a warm  sensation in the pelvic region. The patient will be given a safety stop button that allows to immediately stop the sonication if patient feels some pain.

It has been observed that large number of patients are free of symptoms, usually by third or  fourth menstrual cycle following the treatment.

The body gradually removes the treated dead tissue over a period of months.

Case study

A 30 year old woman came with heavy bleeding and severe abdominal pain during periods since two years. Her  iimmediate post treatment, post contrast scans (A,B) showed non-viable fibroids with volumes of 271 and 61.2 cc respectively . Follow up scan obtained at 6 months (C,D) revealed shrinkage of size and volume reduction by 45 per cent measuring 137 and 40 cc respectively. Second follow up at one year revealed(E, F) 60-70 per cent volume reduction ,measuring 90 and 19cc respectively.

MRgFUS treatment in a C/O residual fibroids post myomectomy with surgical scar and adherent bowel loop to the uterus.

ADENOMYOSIS

Adenomyosis is a benign condition with presence of ectopic endometrial glands and stroma in the myometrium (wall of the uterus) and hyperplasia of adjacent smooth muscles leading to dysmenorrhea, menorrhagia and subfertility MRgFUS has emerged as modality of choice to treat both focal and diffuse Adenomyosis as it can effectively destroy the abnormal cells without surgery, providing good symptomatic relief with acceptable recurrence rates.

Treatment of Adenomyosis –Pre-treatment images (A,B) showing focal enhancing Adenomyosis in posterior wall of uterus. Immediate post treatment scan (C,D) showed non enhancement indicating non-viable tissue. Follow up scan at 3 months (E) and 6 months (F,G) revealed progressive volume reduction.

Advantages of MRgFUS in treatment of fibroids or Adenomyosis

1. Non-invasive, Incision less surgery (no touch technique)
2. No anaesthesia
3. No radiation
4. Short hospital stay (overnight)
5. Short recovery period (patient can return to daily activities the next day)
6. Low complication rate
7. Recurrence rates lower compared to conventional surgery
8. Fertility preserved
9. Cost effective

Other applications of MRgFUS

MRgFUS has various other applications both oncological and otherwise. We at Jaslok hospital have treated patients suffering from facetal arthropathy, bone metastasis, bone tumors and prostate cancer. Upcoming applications include treatment of breast, liver and brain cancer, treatment of movement disorders and epilepsy.