Fluorescein angiography for the detection of metastases of ovarian tumor in the abdominal cavity, a feasibility pilot.

BACKGROUND AND OBJECTIVES: The growth and progression of ovarian tumor metastases at the peritoneal surfaces of the abdominal cavity are coupled with neovascularization. Newly formed tumor vessels show a more diffuse pattern and are more permeable for macromolecules than normal vessels. We investigated the possibility to detect (small) ovarian metastases in the abdominal cavity by means of fluorescein angiography. STUDY DESIGN/PATIENTS AND METHODS: Eighteen patients known with ovarian cancer or with suspicion for this disease received sodium fluorescein intravenously in different doses (0.4-1.6 ml of a 25% solution), whereafter fluorescence detection by laparoscope was carried out. The distribution pattern of fluorescein was gained from 0 to 120 min by pooling the data collected in different patients at various time intervals. RESULTS: Three phases could be discriminated, that is, rapid filling of blood vessels after administration of fluorescein, diffuse extravasation of fluorescein into surrounding tissues, and clearance of fluorescein from vessels and surrounding tissue. Differences in accumulation of fluorescein could be visualized only after 1 hour or more. Fluorescence imaging more then 60 minutes after administration of fluorescein did not give additional information compared to the inspection using white light, which was confirmed by histology. These observations were dose-independent. CONCLUSIONS: The concentration gradient differences of fluorescein between healthy and pathological tissue in the abdominal cavity are too small to indicate tumor neovascularization.

Autofluorescence characteristics of healthy oral mucosa at different anatomical sites.

BACKGROUND AND OBJECTIVES: Autofluorescence spectroscopy is a promising tool for oral cancer detection. Its reliability might be improved by using a reference database of spectra from healthy mucosa. We investigated the influence of anatomical location on healthy mucosa autofluorescence. STUDY DESIGN/MATERIALS AND METHODS: Spectra were recorded from 97 volunteers using seven excitation wavelengths (350-450 nm), 455-867 nm emission. We studied intensity and applied principal component analysis (PCA) with classification algorithms. Class overlap estimates were calculated. RESULTS: We observed differences in fluorescence intensity between locations. These were significant but small compared to standard deviations (SD). Normalized spectra looked similar for locations, except for the dorsal side of the tongue (DST) and the vermilion border (VB). Porphyrin-like fluorescence was observed frequently, especially at DST. PCA and classification confirmed VB and DST to be spectrally distinct. The remaining locations showed large class overlaps. CONCLUSIONS: No relevant systematic spectral differences have been observed between most locations, allowing the use of one large reference database. For DST and VB separate databases are required.