For stereotactic biopsies, the experiment consists of six different parts: (1) A baseline 5
min biopsy planning period during which only imaging occurs after patient positioning and
breast compression is complete, (2) One 2-min local anesthesia administration period during
which the skin is injected with local anesthetic and an incision is made to insert the biopsy
needle into the breast occurs ("stressor 1"), (3) One 2-minute post local anesthesia
administration period during which imaging is obtained to confirm the position of the needle
with respect to the target, (4) One 1-minute sampling period when the breast tissue is
sampled ('stressor 2"), (5) One 2-minute post-CNB period, during which adequacy of obtained
samples is confirmed and the need for additional sampling determined, and (6) One 2-minute
period during which a biopsy marker clip is deployed and pressure dressing placed on the
biopsy site.
For ultrasound biopsies, the experiment also consists of six different parts: (1) A baseline
5 min biopsy planning period during which only imaging occurs after patient is positioning,
(2) One 2-min local anesthesia administration period during which local anesthesia is given
at the site of biopsy and a skin incision performed ("stressor 1"), (3) One post local
anesthesia administration period during which intra-procedure imaging and confirmation of
adequate targeting occurs, (4) One 1-minute first-pass sampling period ('stressor 2") during
which the biopsy device is advanced to the target for the first time and fired to acquire the
first tissue sample, and (5) One 2-minute post-CNB period, following the first needle pass
while sample adequacy is visually assessed and additional intra-procedure imaging occurs, (6)
One 2-minute post-CNB period, during which a biopsy marker clip is deployed and pressure
dressing placed on the biopsy site.
The total time for a single site CNB is approximately 30 minutes when performed under
US-guidance, and 30-45 minutes when performed under stereotactic guidance. The added
physiological recordings for this experiment are not expected to significantly prolong the
duration of CNB procedures.
