Case Studies

Case Study in Reconstructive Microsurgery

Physician Name: Jeffery Marcus, MD, Michael Zenn, MD, Brian Coan, MD
Institution: Duke University Medical Center, Durham, NC
Case Highlight: Facial reanimation with free muscle graft

History:
11 year old, 60 kg male, presented with right sided facial paralysis that occurred secondary to brain tumor excision several years prior. The left side of his face was unaffected. Six months prior to this operation, the child underwent a sural nerve grafting procedure. A portion of the sural nerve was removed from the leg and then sewn to the middle branch of the facial nerve that extended across the face between the nose and upper lip, originating from the left side toward the right. The patient was scheduled for a free gracilis muscle flap.

Operative Procedure and Imaging Assessment:

  • A face lift type incision was made along the right jaw line of the face. The facial artery and vein were identified. The sural nerve graft, placed during the previous operation, was dissected out. This extension of the facial nerve from the right side of the face had been placed between the nose and the upper lip.

  • The gracilis muscle was dissected out and the pedicle, which included the median cutaneous circumflex femoral artery and vein, and the obturator nerve were identified.

  • The SPY System was first used to visualize the gracilis muscle flap insitu. To image, 5.0 mg of Fluorescence Agent was injected peripherally. SPY demonstrated excellent perfusion in the muscle graft.

  • The muscle graft was split into sections in situ, and a second image sequence was performed. Again, 5.0 mg of Fluorescence Agent was administered peripherally. SPY demonstrated two different areas of perfusion. The muscular section of the targeted tissue with the best perfusion was resected and used for grafting.

  • The graft was placed in the right cheek area and, under microscopic surgery, the arterial and venous anastomoses were completed. Arterial and venous Doppler probes were applied, but the Doppler signal was questionable, possibly due to the size of the vessels.

  • A third SPY image was captured. The image sequence showed excellent perfusion with arterial in-flow, muscle perfusion and venous outflow and therefore no need for anastomotic revision. The coupling device used for the venous anastomosis is visualized.

  • The facial/sural nerve was then connected to the obturator nerve which was part of the muscle graft. The facial and leg incisions were closed.

Conclusion:
The patient tolerated the surgery well and enjoyed an uneventful postoperative period after routine time was spent in the ICU. In surgery, SPY provided real-time visual and functional information that enabled sound intra-operative decisions. Without SPY, a needless anastomotic revision might have been performed. SPY increased surgeon confidence during the performance of this highly complex case.

 

Case Study in Colorectal Surgery


Physician Name: Helen Sohn, MD
Institution: University of Southern California University Hospital, Los Angeles CA
Case Highlight: Exploratory laparotomy, small bowel resection

History:
The patient is a 65 year old female s/p CABG with no known allergies. The patient developed symptoms of an ischemic bowel on post-op day two. The patient was returned to the operating room for an exploratory laparotomy.

Operative Procedure and Imaging Assessment:

  • During the operative procedure, the abdomen was incised and it was confirmed that some portion of the small bowel was ischemic. To assess the full extent of the ischemia the surgeon chose to use SPY fluorescence imaging.
  • Prior to imaging, the anesthesiologist reconstituted 25 mg of Fluorescence Agent with 10 cc of aqueous solvent. To image, 2.5 mg of Fluorescence Agent was administered intravenously, followed by a brisk 10 cc flush of normal saline prior to each imaging sequence. Imaging capture was initiated 5 seconds following confirmation of the delivery of the normal saline flush.
  • During the imaging procedure, the 60 second capture provided the surgeon with ample time to visualize all of the areas of ischemic bowel. SPY imaging confirmed that there were several areas of ischemia in the bowel rather than one large isolated area. The areas of ischemia were easily identified during the imaging procedure. To prevent the need for more than one anastomosis, the surgeon decided to resect a large portion of the small bowel.
  • Following the resection, the surgeon performed an additional SPY image to confirm that all areas of ischemic bowel had been resected.The SPY image confirmed that there were no additional areas of ischemia and the anastomosis was performed without incidence.


Conclusion:
Following the small bowel resection, the patient recovered without any further complications. The patient was discharged from the hospital in stable condition.

Surgeon comments about SPY:
The SPY System was easy to use and provided objective data, which allowed the best clinical decision to be made while the patient was in the operating room. The ability to definitively and quickly visualize the demarcation between viable and non-viable tissue in the small bowel reduced operating room time and increased surgeon confidence in knowing that the resection was complete and the surgery was successful.

SPY is not yet cleared for use in pediatric populations or colorectal surgery.