Table 4.

Technical recommendations for use of the SPY System

Application	Timing of evaluation*
Microvascular reconstructive surgery
Pre-incision identification of perforators	15-30 sec
Following dissection, confirmation of adequate flow and limits of perfusion	1-2 min
Following transfer, evaluation of arterial and venous anastomoses	Arterial phase: instantaneous.
	Venous phase: 30–60 sec
	Re-image at 2 min; if venous congestion is suspected, evaluate again at ≥4 min
Following inset, confirmation of adequate flow and limits of perfusion	1-2 min (Wait at least 10 min following previous ICG administration)
Pedicle flap reconstruction
Pre-incision identification of perforator perfusion zone	≤1 min
Following elevation of flap, confirmation of adequate flow and limits of perfusion (selection of skin and soft tissue for preservation)	1-2 min
Following transposition and inset, confirmation of adequate flow and limits of perfusion	1-2 min
Skin flap reconstruction**
Following elevation of skin flap, define limits of perfusion for flap design and detect sub-clinical ischemia	1-2 min
Following transposition and inset to confirm adequate perfusion	1-2 min (Wait at least 10 min following previous ICG administration)
Mastectomy followed by TE/I reconstruction
Pre-mastectomy, map the vessels and the perfusion surrounding the nipple-areolar complex	15-30 sec
Following mastectomy, assess perfusion along the skin/tissue edges of the flap† Wait 30–45 minutes following completion of mastectomy procedure to ensure recovery of perfusion. If no fluorescence is detected after this time period, additional wait time of up to 30 minutes may be appropriate.	3-4 min
With implant or tissue expander in place, evaluate mastectomy skin flap prior to filling expander	Wait 5 min after insertion of implant or tissue expander before imaging
After filling tissue expander, evaluate skin flaps, nipple-areolar complex, and surrounding tissue perfusion	Wait 5 min after filling tissue expander before imaging

TE/I = tissue expander/implant.

* Start recording after first appearance of fluorescent blush. Times given indicate when within the captured image sequence assessments should be made.

**For areas or conditions associated with reduced perfusion (eg, lower extremities, vasculopathy), longer wait times may be required before evaluation.

Notes: The Instructions for Use supplied with SPY note that the 25 mg ICG should be reconstituted in 10 cc of normal saline, giving a concentration of 2.5 mg/cc [15]. The Instructions for Use suggest administration of 10 mg (or 4 cc) ICG for visualization of tissue perfusion. For restudy, wait ≥10 min from previous injection of ICG. Take a baseline image before restudy to ensure that ICG has washed out. If complete wash out is needed, wait 15 minutes from previous ICG administration.