Intraoperative Near-Infrared Optical Imaging Can Localize Gadolinium-Enhancing Gliomas During Surgery

Abstract

Background Although real-time localization of gliomas has improved with intraoperative image guidance systems, these tools are limited by brain shift, surgical cavity deformation, and expense. Objective To propose a novel method to perform near-infrared (NIR) imaging during glioma resections based on preclinical and clinical investigations, in order to localize tumors and to potentially identify residual disease. Methods Fifteen patients were identified and administered an FDA-approved, NIR contrast agent (Second Window indocyanine green [ICG], 5 mg/kg) prior to surgical resection. An NIR camera was utilized to localize the tumor prior to resection and to visualize surgical margins following resection. Neuropathology and MR imaging data were used to assess the accuracy and precision of NIR-fluorescence in identifying tumor tissue. Results NIR visualization of 15 gliomas (10 glioblastoma multiforme, 1 anaplastic astrocytoma, 2 low grade astrocytoma, 1 juvenile pilocytic astrocytoma, and 1 ganglioglioma) was performed 22.7 hours (mean) after intravenous injection of ICG. During surgery, 12/15 tumors were visualized with the NIR camera. The mean signal-to-background ratio was 9.5 ± 0.8 and fluorescence was noted through the dura to a maximum parenchymal depth of 13 mm. The best predictor of positive fluorescence was enhancement on T1-weighted imaging; this correlated with SBR (P = .03). Non-enhancing tumors did not demonstrate NIR fluorescence. Using pathology as the gold standard, the technique demonstrated a sensitivity of 98% and specificity of 45% to identify tumor in gadolinium-enhancing specimens (n = 71). Conclusion Using Second Window ICG, gadolinium-enhancing tumors can be localized through brain parenchyma intraoperatively. Its utility for margin detection is promising but limited by lower specificity.

A Clinical Trial of TumorGlow to Identify Residual Disease During Pleurectomy and Decortication

“…No other adverse events were noted within this cohort. The low toxicity profile in MPM is in accordance with our experiences with central nervous system malignancies and other pulmonary malignancies (10, 11, 15). …”

“…Approximately 24 hours prior to surgery, subjects were infused with ICG (5 mg/kg) (Akorn Pharmaceuticals, Illinois) as previously described by our group (14, 15). ICG has an excitation and emission wavelength of 805nm and 830nm, respectively.…”

“…ICG has an excitation and emission wavelength of 805nm and 830nm, respectively. NIR imaging was performed using the Iridium system optimized for detection of ICG (Visionsense Corp, Philadelphia, PA) as previously described by our (14, 15). The Iridium is a high definition, dual band (white light and NIR) camera system which uses an excitation laser (805nm) and detects fluorescence using a bandpass filter (825 to 850nm).…”

Real‐Time Imaging of Brain Tumor for Image‐Guided Surgery

“…[40] Real-time ICG NIR imaging correlates with contrast enhancement on preoperative MRI scanning data and is able to identify tumor margin. [80] …”

“…Rapid clearance of ICG ( t 1/2 ≤ 5 min) requires continuous injection, which may exceed the lethal dose, limiting its use in the brain tumor surgery. [80] …”