NBI Video Atlas and experts’ commentary about NBI technique

We use NBI at all cystoscopies where urothelial malignancy is suspected. This includes all patients coming for outpatient flexible cystoscopy for haematuria work-up and all patients with a previous history of urothelial carcinoma coming for follow-up cystoscopy. If in doubt during the first white light cystoscopy, we switch directly to NBI to estimate whether to biopsy a suspicious mucosal area or not.

NBI is used when during the overview cystoscopy before resection in TURBT patients. This facilitates identification of small lesions that should be biopsied or coagulated during the procedure in order to have the correct diagnosis of CIS and avoid “early recurrences” because of over-looked small lesions.

NBI is recommended for all cystoscopies where there is a risk of urothelial cancer. This includes specifically (but no limited to) patients coming for first TURBT in order to identify CIS and patients where white light cystoscopy and CT-urography is normal but the patient has malignant cells in the cytology. NBI can here help identifying otherwise overlooked flat lesions and guide the surgeon for biopsies the correct site in the bladder. Selected site biopsies are therefore made superfluous if NBI is available.

NBI helps by improving the contrast between normal flat mucosa and neoplastic more thick and irregular mucosa. The latter gives a more dark appearance of the neoplastic areas which can more easily be identified. Moreover, the addition capillary structure of both small papillomatous tumors and CIS areas has a very characteristic “frog’s egg” appearance that is almost patognomic for CIS. The latter can guide the surgeon whether to perform a biopsy of red patches in the bladder mucosa or not.

Tumor grade does not affect the ability to identify it in NBI. On the other hand, tumor grad cannot be estimated based on the NBI appearance alone at the present time.

We use NBI following the initial overview white light cystoscopy in order to detect additional small lesions or flat lesions (e.g. CIS) that have been missed by the initial white light cystoscopy. This ensures thoroughness that will follow the dual procedure by itself but will also lead to better identification of small and flat lesion owing to the NBI effect. Moreover, if in doubt during the first white light cystoscopy, we switch directly to NBI to estimate whether to biopsy a suspicious mucosal area or not.

During the resection part of the TURBT, we use white light and not NBI as coagulated non-vital areas still looks falsely vital in NBI.