Mieke Bus

60 Chapter 4 line. All anatomical layers could be identified. In suspected areas, a flat broadened urothelial layer with low reflectivity was seen (Figure 5A and Figure 5B). No µ oct could be obtained from the suspected areas. As 4 out of 8 biopsies showed carcinoma in situ, a right-sided nephro- ureterectomy was performed. Histopathological examination of the nephroureterectomy specimen confirmed CIS in the pyelum, proximal ureter, mid and distal ureter. In 3D OCT reconstruction suspected areas were seen (Figure 5C). Figure 5: A & B) In-vivo cross-sectional OCT images of the ureter with a flat, broadened urothelial layer (*). Anatomical layers could be identified with lamina propria and muscularis propria presenting. The basal membrane presents as a thin dark line (#), suggesting a non-invasive tumor. Corresponding histology of the nephroureterectomy specimen showing CIS (*, right) and basement membrane (#). C) 3D pullback of the OCT build from 520 individual cross-sectional images over a length of 5.2cm.