Endoscopic Resection of an Intraventricular Tumor With Second Window Indocyanine Green: 2-Dimensional Operative Video.

A 26-year-old woman presented to our clinic with years of headaches and mental clouding. She had a nonfocal neurological examination including benign ophthalmological examination. Head computed tomography and brain magnetic resonance imaging (MRI) demonstrated asymmetry of the lateral ventricles due to a lesion arising from the foramen of Monro. At the top of our differential diagnosis were choroid plexus tumor and colloid cyst. We offered the patient treatment via an endoscopic approach. Here, we demonstrate the feasibility of using tumor-localizing dyes such as indocyanine green (ICG) in conjunction with endoscopes equipped with lasers to localize and treat intraventricular lesions. While ICG is FDA approved, the technique presented here is investigational and the dye is being used off-label. The laser-equipped endoscope is also being used off-label. To treat the ventricular asymmetry, we performed an endoscopic septostomy between the frontal horns of the lateral ventricles. For our tumor-localizing dye technique, we injected the patient with ICG 24 hours before the planned surgery. We were able to clearly visualize the lesion at the foramen of Monro as it was intensely fluorescent. The dye also appeared to localize to the presumably normal choroid plexus. We resected the lesion endoscopically and permanent pathology revealed that the lesion was a choroid plexus papilloma. The postoperative MRI showed improvement in her ventricular asymmetry and complete resection of the enhancing lesion at the foramen of Monro. The patient recovered well and was uneventfully discharged. She was seen in follow-up and has had improvement in her headaches.Consent for surgery was obtained from the patient. Consent for publication of the operative video was also obtained from the patient.