====== Second Window Indocyanine Green ====== Second Window [[Indocyanine Green]] (SWIG) is a novel technique for real-time, intraoperative tumor visualization using a high dose infusion of Indocyanine Green (ICG) 24 hours before surgery. Due to pathologic diversity found in the [[pineal region]], tissue diagnosis in patients with pineal region mass is essential to optimize further clinical management. ===== Case reports ===== Cho et al. presented a case of a 75-year-old woman with known pineal region [[mass]] for 18 years, who presented with progressive classic signs and symptoms of [[obstructive hydrocephalus]] over the past six months. The preoperative imaging confirmed a contrast-enhancing [[pineal region tumor]], which appeared to be obstructing the [[aqueduct of Sylvius]], causing proximal obstructive hydrocephalus. 5mg/kg of [[ICG]] was delivered intravenously 24 hours before the surgery. The patient underwent an [[endoscopic third ventriculostomy]] and a [[biopsy]] of the [[pineal]] lesion. The [[tumor]] demonstrated clear near-infrared fluorescence which was distinct from surrounding [[third ventricle floor]] and [[ependyma]]. The signal to background ratio was 2.9. The final pathology report revealed a WHO Grade I [[pineocytoma]]. They reported on a novel application of near-infrared [[fluorescence]] for tumor identification of [[pineal region tumor]]s, using the Second Window ICG technique ((Cho A, Cho SS, Buch VP, Buch LY, Lee JYK. Second Window ICG Near Infrared Fluorescent TransVentricular Biopsy of a Pineal Tumor: A Case Report with a 2-Dimensional Operative Video. World Neurosurg. 2019 Oct 26. pii: S1878-8750(19)32741-X. doi: 10.1016/j.wneu.2019.10.113. [Epub ahead of print] PubMed PMID: 31669685. )).