Characterization of indocyanine green fluorescence imaging patterns of pheochromocytomas

Imaging guided adrenalectomy with Indocyanine green fluorescence in a dog with a pheochromocytoma

IMPORTANCE

This case report presents the successful surgical removal of a pheochromocytoma in a dog using indocyanine green (ICG) fluorescence imaging.

CASE PRESENTATION

A 10-year-old, 6.87 kg, spayed female poodle was referred for an abdominal mass and eight episodes of vomiting. Computed tomography revealed masses in the spleen and left adrenal gland. Based on the plasma normetanephrine levels, the patient was diagnosed with pheochromocytoma. Subsequently, a total splenectomy and left adrenalectomy were performed. A dose of 5 mg/kg ICG was administered intravenously 24 h prior to surgery. Using ICG allowed visualization of tumor margins, aiding in complete resection and minimizing anesthesia-related risks.

CONCLUSIONS AND RELEVANCE

No evidence of recurrence or metastasis has been observed for 12 months. To our knowledge, this is the first report of the surgical removal of a pheochromocytoma using intraoperative ICG imaging in veterinary medicine. This case highlights the efficacy of ICG fluorescence imaging as a valuable tool for the surgical management of adrenal tumors in veterinary medicine.

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

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.