Usefulness of 4K-resolution Indocyanine Green Endoscope for the Removal of Spontaneous Intracerebral Hematomas

Indocyanine green (ICG) is a cyanine dye useful for visualizing blood vessels; it has been developed for endoscopy and is used in skull base surgery. Endoscopy is widely used for hematoma removal after an intracerebral hemorrhage since it is minimally invasive and has a shorter operation time than craniotomy. However, with this technique the surgical field is limited and it is difficult to obtain an adequate orientation; thus, it is challenging to locate the bleeding point, and postoperative rebleeding has been reported. We performed intraoperative ICG near-infrared fluorescence imaging to locate the bleeding point. This purpose of this study was to evaluate the usefulness of ICG angiography during endoscopic hematoma removal in two patients, using two endoscope types and comparing their visualization of perforating branches during the procedure. ICG angiography was performed in two different cases of putaminal hemorrhage, using the SPIES NIR/ICG-System and IMAGE1 S Rubina (both KARL STORZ, Tuttlingen, Germany) at the intraoperative bleeding site. The intraoperative use of ICG allowed the clear visualization of the perforating branches and real-time confirmation of active bleeding. We could also distinguish an old hematoma from the active bleeding point. The IMAGE1 S Rubina has adequate brightness for contrast enhancement, allowing surgical manipulation simultaneously to the enhancement phase. ICG fluorescence angiography is useful to identify the damaged vessel and perform hemostasis. We expect other similar devices to be developed in the future, accompanied by flexible and thin rigid endoscopes.