Fluorescence-guided minimally-invasive resection of abdominal paragangliomas using indocyanine green

Abstract

This retrospective study explores the utility of near-infrared (NIR) fluorescence imaging with indocyanine green (ICG) in enhancing the intraoperative identification and guidance for the resection of abdominal paragangliomas. They can be challenging to detect during minimally invasive surgery, due to their anatomical location, varying size and similar appearance in regard to their surrounding tissue. Patients with suspected abdominal paragangliomas planned for a minimally-invasive resection were included. As part of standard of care they received single intravenous dose of 5 mg ICG after abdominal exploration. NIR fluorescence imaging of the anatomical region of the suspected lesion was performed immediately following intravenous administration, to assess fluorescence signals, intraoperative identification, and histopathological correlation. Out of five resected suspicious lesions, four were imaged with NIR fluorescence, pathology confirming four as paragangliomas, the latter turned out to be an adrenal adenoma. NIR fluorescence identified all four lesions, surpassing the limitations of white-light visualization. Homogeneous fluorescence signals appeared 30-60 s post-ICG administration, which lasted up to 30 min. The study demonstrates the feasibility and potential clinical value of fluorescence-guided minimally-invasive resections of abdominal paragangliomas using a single intravenous ICG dose. These findings support the scientific basis for routine use of ICG-fluorescence-guided surgery in challenging anatomical cases, providing valuable assistance in lesion detection and resection.

Figure 1

Multimodal workflow of perioperative diagnostics of subject 1. Detailed overview of subject 1, diagnosed with a 27 mm lesion on the cranial side of the left renal hilus, just above the renal artery. Suspected for paraganglioma, based on abdominal CT, MRI and additional I¹²³ * Corresponding location on different imaging modalities (A). Surgical robot-assisted resection and NIR fluorescence imaging was performed using the Intuitive da Vinci Xi surgical robot in FireFly-mode, t = 31 s after IV administration of Indocyanine Green (ICG) homogenous fluorescence signal was detected using the NIR-channel (B). Administration-Imaging timeline for NIR-fluorescence imaging of abdominal paragangliomas (C). Created with biorender.com. CT contrast-enhanced computerized tomography; ICG Indocyanine Green; IV Intravenous; NA not applicable; NIR Near-infrared Fluorescence; MIBG Meta-iodobenzylguanidine; MRI Magnetic Resonance Imaging.

Figure 2

Multimodal overview of included cases, referenced to histopathology. Detailed overview of subject 1–4 with preoperative (PET)/CT-scan used during the diagnostic work-up (A), Color-video image of surgical field (B), the in-vivo identification in the suspected tumor during minimally-invasive procedures (C), Hematoxylin and eosin (HE) stained resection slides and corresponding ex-vivo NIR fluorescence scans of blank histology slides (C) [LI-COR Odyssey CLx, Lincoln, NE, U.S.A.]. Subject 4 (Panel A): Based on the preoperative work-up there was a discrepancy in the suspected lesion location and diameter based on CT and ⁶⁸ Ga-Octreotide PET/CT-scan, in-vivo the lesion corresponding with the ⁶⁸ Ga-Octreotide PET/CT-scan was identified. Subject 4 (Panel D): Microscopic slide with two 4um tissue sections of the same lesion. (Subject 1–3: da Vinci Xi [Intuitive, Sunnyvale, California, United States of America] robot-assisted surgical system, in FireFly-operating mode; Subject 4: Image 1S RUBINA laparoscopic imaging system [KARL STORZ SE & Co. KG – Tuttlingen, Germany] in overlay-operating mode). Created with biorender.com. CT contrast-enhanced computerized tomography; ⁶⁸ Ga, 68-Galium; HE Hematoxylin and eosin; ICG Indocyanine Green; MRI Magnetic Resonance Imaging; NIR Near-infrared Fluorescence.