How many biopsy cores should be obtained during an MRI-targeted biopsy?
The current recommendation is two cores per lesion. There is a debate as to whether one might be enough for an MRI in-bore biopsy.
MRI in-bore biopsy (done in ambulatory setting):
Patient preparation:
Coagulation parameters (INR, aPTT) were performed and reviewed before the procedure.
Written informed consent was obtained.
Periprocedural antibiotics were administered.
Fasting for 4 hours before the procedure. Rectal cleansing with enema.
Procedural details:
The patient is placed in a prone position on the MRI table.
After a digital rectal exam (DRE) and intrarectal instillation of sterile lidocaine gel, the needle guide is introduced into the patient's rectum.
A portable biopsy device is connected to the MRI table and the needle guide.
Sagittal and oblique T2W image stacks, as well as axial T2W and DWI sequences, are acquired.
Image sequences are transferred to a planning workstation.
The needle guide is used as a fiducial reference point and calibrated to the system with the software.
The suspicious lesion in the left midglandular, posterolateral zone (PZpl) is re-identified on the images, marked and locked using the software.
Planning coordinates and needle length are obtained.
This information is used to direct the needle guide of the biopsy device in the MRI gantry.
Control oblique T2W images are obtained to verify the accurate orientation of the needle guide to the suspicious lesion.
An 18G, 150 mm biopsy needle is introduced.
Oblique T2W images are obtained again to document the biopsy needle position within the lesion.
Two biopsy cores are obtained from the lesion, registered and sent to pathology.
The needle guide was withdrawn and a tampon soaked with antiseptic gel is introduced into the rectum.