Nuclear Medicine DMSA Scan
What is a DMSA scan? DMSA, or dimercaptosuccinic acid, is bound to technetium 99m to form the radiopharmaceutical, 99m-Tc DMSA.…Read more
A hookwire localisation is an imaging-guided procedure, carried out on the day of breast surgery, in which a radiologist will use imaging to place a hookwire into a breast lesion before surgery.
This may be done with ultrasound, mammography or MRI to guide the wire placement. The choice of imaging modality depends on which was the easiest and most accurate in identifying the lesion.
A hookwire may not be needed for all operations, but is usually used in patients where the lesion is not palpable, breasts are lumpy or the lesion is very small, and is decided by the surgeon and radiologist in advance of the operation.
Hookwire placement is decided by the surgeon and radiologist in advance of the procedure, and is usually carried out for small or impalpable lesions. In addition, it is usually carried out in patients where an excisional biopsy, lumpectomy or wide local excision is desired and the remainder of breast is to be spared.
The treating multidisciplinary team, including at least the operating surgeon and a radiologist, should decide the timing and method of localisation. All previous imaging should be assessed and made available by the treating team before localisation. In general, if a lesion is seen by one modality only, that modality will be the one chosen to guide the localisation procedure.
For mammographic hookwire procedures, the patient should be capable of sitting in a chair and understanding simple instructions.
MRI contraindications and renal function status (for IV contrast administration) should be reassessed before localisation.
It is useful to be aware of the patient’s coagulation status, including platelet count, haemoglobin, activated partial thromboplastin time and international normalised ratio (this would be standard information required before any radiological interventional or surgical procedure).
There are no absolute contraindications for breast hookwire localisation. There are some absolute contraindications for MRI guidance outlined in the MRI item.
Relative contraindications are also rare, as these would usually have been encountered in the diagnostic phase of work-up and would inform the choice of the subsequent localisation procedure.
Vasovagal reactions occur in approximately 7% of hookwire localisations. The risk of a vasovagal attack is increased by patient anxiety. The radiology practice should employ anxiety-reducing strategies, including the provision of a relaxed and friendly atmosphere, and fast, efficient procedures, so that most vasovagal reactions are avoided or minimised.
Adverse events related to MRI in general include the small risk of allergic reactions to gadolinium, the risk of nephrogenic systemic fibrosis in women with kidney failure who receive gadolinium during the localisation procedure and the general risks of entering the MRI environment, such as pacemaker malfunction or metallic foreign body migration. See items on MRI and gadolinium contrast medium.
Wire misplacement or migration can affect the accuracy of excision, and occasionally small wire fragments are retained in the breast. These rarely cause harm.
The wire will be placed securely on the skin, and the patient will be transferred to the operating room shortly after. No specific care is needed in the interim.
Alternatives to hookwire localisation include injection of medical carbon as a track to the lesion, injection of radionuclide tracer into the lesion, and deposition of various clips and markers at the time of diagnostic needle biopsy. These alternative methods usually then involve intraoperative localisation by the surgeon with an ultrasound probe or a gamma probe, in the case of radionuclide injection, without the need for a preoperative radiological localisation method. The choice of timing and method is made by the treating multidisciplinary team, and will vary according to the available facilities and expertise. All methods have excellent track records when success is measured on the basis of correct identification and removal of the lesion.
Page last modified on 19/12/2019.
RANZCR® is not aware that any person intends to act or rely upon the opinions, advices or information contained in this publication or of the manner in which it might be possible to do so. It issues no invitation to any person to act or rely upon such opinions, advices or information or any of them and it accepts no responsibility for any of them.
RANZCR® intends by this statement to exclude liability for any such opinions, advices or information. The content of this publication is not intended as a substitute for medical advice. It is designed to support, not replace, the relationship that exists between a patient and his/her doctor. Some of the tests and procedures included in this publication may not be available at all radiology providers.
RANZCR® recommends that any specific questions regarding any procedure be discussed with a person's family doctor or medical specialist. Whilst every effort is made to ensure the accuracy of the information contained in this publication, RANZCR®, its Board, officers and employees assume no responsibility for its content, use, or interpretation. Each person should rely on their own inquires before making decisions that touch their own interests.