Participants will undergo 5-ALA guided tumour resection via craniotomy with the aim of achieving maximal safe tumour resection without significant neurological deficit. On completion of tumour resection, digital images will be taken of the resection cavity under blue light using (i) an in-built camera in the operative microscope and (ii) an ultra-high sensitivity camera attached to the side arm of the operative microscope. Biopsies approximately 5x5x5mm in size will then be taken from the anterior, posterior, lateral and inferior areas of the resection cavity which were imaged. These biopsies will be analysed by histopathology to determine the presence of glioma cells.

An ultra-high sensitivity camera attached to the side arm of the operative microscope will be used to take images of the anterior, posterior, lateral and inferior walls of the resection cavity on completion of tumour resection.

Levels of tumour fluorescence in intra-operative images of the resection cavity taken by the ultra-high sensitivity camera and the in-built camera in the operative microscope will be measured. These fluorescence levels will then be used to calculate the sensitivity and specificity of the in-built camera and ultra-high sensitivity camera to detect glioma tissue.

Time points measured will include (i) time from arrival in theatre to start of operation, (ii) total operation duration and (iii) time from acquisition of images to availability of processed images available for the surgeon to view.