Indocyanine green endoscopic evaluation of pituitary stalk and gland blood flow in craniopharyngiomas

Objective: We aimed to assess the use of indocyanine green (ICG) fluorescence endoscopy to evaluate pituitary blood flow in craniopharyngioma resection and its possible impact on intraoperative decisions regarding pituitary stalk processing. Methods: Patients with craniopharyngiomas who had undergone transsphenoidal surgery since March 2021, when an ICG endoscope was introduced at Kagoshima University Hospital, were included in the study. When targeted tumor removal was approaching completion, 10 mg of ICG was administered intravenously, and blood flow in the pituitary stalk and gland was evaluated. Subsequently, ICG signals and endocrinological status before and after surgery were evaluated retrospectively. Pituitary stalk and gland blood flow was evaluated as sufficient (++), weakly positive (+), and no signal (-). Results: Ten patients with craniopharyngiomas underwent transsphenoidal surgery using an ICG endoscope (mean age 56.6 ± 14.2 years; 40% male). Among the eight patients in whom the pituitary stalk was preserved, pituitary function with sufficient signal on the stalk was intact in two. Two other patients with weakly positive stalk and sufficient pituitary gland signals showed intact function or minimal pituitary dysfunction. Four patients had impairments in more than three axes with poor ICG signals in the stalk or pituitary gland. Two patients underwent pituitary amputation because of high tumor invasion and lack of ICG signal in the stalk after tumor removal, resulting in panhypopituitarism. Conclusion: A negative ICG signal is likely to indicate postoperative loss of pituitary function. Craniopharyngioma surgery using ICG endoscopy may be useful for predicting endocrine prognosis and improving tumor outcomes.