I See G: Superior Hypophyseal Artery Intraoperative Indocyanine Green Angiogram as a Predictor of Postoperative Visual Function After Endoscopic Endonasal Surgery

Summary

Endonasal endoscopic approaches are an established treatment for suprasellar lesions compromising the optic nerves (ON). Surgery often involves dissecting tumors from the optic nerves and its blood supply, which can result in nerve damage and visual loss after surgery. To date, there are no reliable methods to monitor the optic nerve function during surgery and thus, post-surgical visual outcomes is unknown until the patients are fully awake after surgery for a visual exam. This delay in diagnosis prevents early therapeutic measures and can result in further harm to the ON. We have recently recognized that when ICG is routinely injected during these cases to check for patency of the big arteries the sub millimetric superior hypophyseal arteries supplying (SHA) the ON are also visible and that lack of visualization of these vessels is associated with worse visual deficits after surgery. Thus, ICG may be a tool to intraoperative predict visual outcomes after endonasal approach for suprasellar lesions and fill the nondiagnostic gap. This study will assess whether endoscopic ICG angiography before and after resection of suprasellar lesions can predict post-operative visual deficits. Successful completion will provide surgeons a novel tool to assess visual function during surgery. The ICG endoscopic angiograms suggested in this study are noninvasive and currently routinely performed at the end of surgery to check for patency of big brain arteries.

Eligibility

Age range

18+ years

Sex

All

Healthy volunteers

No

Interventions

• Procedure
  Indocyanine Green

  Tumor resection, direct visualization of the chiasm and both optic nerves and ICG administration will be provided as it is recommended by the standard of care. ICG will be administered by an injection of 5 mg of ICG diluted in a 10 mL syringe performed in the line closest to the heart followed by a 10-mL saline bolus. Using near-infrared lighting, the investigators will determine the time between anterior cerebral arteries (ACA) peak luminescence to the peak luminescence of the superior hypophyseal arteries enveloping the optic chiasm (ACA to chiasm time). Because luminescence of large vessels precedes small arterial penetration, signal from the ACAs was considered as "time 0" to account for possible differences in the arm-brain time between patients. In addition, the investigators will analyze the proportion of superior hypophyseal branches on the chiasm that luminesced from ICG.

Location