Proceedings Article | 4 March 2019
KEYWORDS: Surgery, Endoscopy, Multispectral imaging, Tissues, Endoscopes, Brain mapping, Image quality standards, Nose, Brain, Tissue optics
Pituitary adenomas are benign tumours of the pituitary gland, a pea-sized organ situated behind the nose, attached to the base of the brain. During transsphenoidal endoscopic surgery to remove pituitary adenomas, it is important to distinguish normal pituitary tissue from adenoma, both to maximize the completeness of resection, and to minimize damage to healthy tissue, thus preserving endocrine function.
Standard of care intraoperative white light imaging often displays low contrast between healthy pituitary tissue and adenoma. Multispectral imaging (MSI), which allows simultaneous collection of morphological (spatial) and biochemical (spectral) information, can help to more effectively delineate tissue types. This motivated the design and construction of a compact, clinically translatable endoscope capable of capturing multispectral images during transsphenoidal surgery.
The multispectral endoscope employs a spectrally resolved detector array (SRDA) with 9 spectral filters (8 narrow bands; average FWHM 30nm, center wavelengths 553, 587, 629, 665, 714, 749, 791, 829nm; 1 broadband; 500–850nm). The SRDA was coupled to a standard clinically approved 4mm rigid endoscope, through which broadband (400–750nm) and narrowband (400–480nm) illumination were supplied sequentially for reflectance and fluorescence imaging respectively.
Subjects due to undergo transsphenoidal surgery to resect pituitary adenoma were enrolled for experimental imaging in a pilot clinical study (MAPS). Images were captured before, during and after resection of the adenoma. Here, we present the results from these first-in-human tests, including evaluation of the image quality and classification potential of the multispectral image cubes.