Magseed clip insertion

X-Ray & Imaging Clinic

What is Magseed? 

Magseed is a sterile, surgical grade steel clip that is about the size of a grain of rice. It is inserted prior to surgery next to the breast cancer to help guide surgeons during a breast lumpectomy. 

How is a Magseed placed in my breast? 

The Magseed is placed with the help of either an ultrasound or a mammogram. A needle is inserted into the tumour within the breast under local anaesthetic and the Magseed is placed. This will performed by your Radiologist. 

How does it help during surgery?

During your operation, the surgeon uses a handheld probe called Sentimag®, which works like a metal detector, to find the location of the Magseed in your breast. From the surface of your skin, your surgeon can detect the exact location of the Magseed next to the cancer and then plan the incision and operation accurately. 

Why are markers needed for breast cancers? 

While some tumours can be felt easily, approximately one third of all breast cancers are not always so easy to feel (palpable). In order for your consultant to accurately locate the cancer during surgery, the breast is marked by our radiologists, using mammography or ultrasound. 

Traditionally, this was done using a rigid wire as a marker, which requires a procedure a few hours before the operation. However, a Magseed can be placed into the breast in advance allowing you to continue your daily life in the lead-up to your operation. The wire marker is not always easy for surgeons to feel in the breast, but Magseed takes them directly to the tumour.

How is a Magseed removed? 

At the time of surgery, a magnetic Sentimag® probe is used to locate the marker. The probe makes sounds of different pitches allowing your surgeon to know how close they are to it. The seed will then be remove at the same time as the tumour. 

What are the benefits of Magseed? 

The seed can be placed in the breast days or weeks prior to surgery, removing the need for a local anaesthetic procedure on the day of surgery. In addition, it offers a more comfortable patient experience, avoiding the need for you to sit in the ward waiting for surgery with the wire protruding from your breast surrounded by a bulking protective dressing. 

Are there any risks? 

The main risk associated with Magseed is, if the moves from its original position; which could lead to the wrong piece of tissue being removed during surgery. But this same risk remains when a guide wire is used.

X-Ray & Imaging Clinic
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108 Harley Street, London, W1G 7ET

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