Differentiating between pilocytic astrocytomas (PA) and hemangioblastomas (HB) during surgery is challenging due to their radiological similarities but distinct vascular characteristics and surgical considerations. This study explores the application of indocyanine green (ICG) fluorescence angiography for intraoperative differentiation of these tumors.

Four patients with cerebellar cystic masses underwent surgical resection using ICG video angiography. ICG fluorescence patterns were observed intraoperatively to distinguish vascular characteristics. Homogeneous enhancement in HB was hypothesized to contrast with the nonenhancing nodules of PA. The findings were correlated with preoperative imaging and histopathology.

In cases of HB, ICG angiography demonstrated early-phase homogeneous fluorescence, highlighting the tumor's high vascularity and aiding complete resection while preserving vascular integrity. In contrast, PA showed no fluorescence in the tumor nodule, enabling piecemeal resection with minimal blood loss. Histopathological diagnoses confirmed the intraoperative findings. The technique was safe, with no complications reported.

This study demonstrates the utility of ICG video angiography as an intraoperative adjunct for differentiating PA from HB. Compared with digital subtraction angiography, ICG offers a cost-effective, safe, and efficient alternative, without the need for specialized equipment or radiation exposure. ICG fluorescence enhances intraoperative decision-making and optimizes surgical outcomes for challenging posterior fossa lesions. Further studies are warranted to validate these findings and expand the role of ICG in neurosurgical practice.

B.P.: Conceptualization, formal analysis, visualization, writing—original draft. D.K.: Visualization, writing—review and editing. K.K.Ö.: Writing—review and editing. A.A.: Data curation, methodology. T.K.: Conceptualization, methodology, supervision, writing—review and editing.

The Declaration of Helsinki is followed during the investigation. Before being enrolled in the study, each participant signed an informed consent form that had been authorized by the institutional review board.

The signed informed consent form for this study includes approval to publish clinical and medical information. The patients gave written informed consent for their individual cases to be published, allowing for the release of the patient's medical records and any related photos. Upon request, a copy of the permission form is provided.

Received: 02 October 2025

Accepted after revision: 06 April 2026

Accepted Manuscript online:
09 April 2026

Article published online:
01 July 2026

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