Fluorescence emission and diffuse reflectance spectra of freshly excised cervical tissue were studied with two specially designed contact probes. The objective of the study was to reach a better understanding of the relationship between spectroscopic measurements and cervical tissue morphology. Tissue samples from loop electro-surgical excision and hysterectomy specimens were measured within 20 to 90 minutes of excision. Emission spectra with 337 nm excitation, and reflectance spectra were collected at wavelengths between 370 and 720 nm from different tissue sites. Hematoxylin-eosin stained slides of the measured zones were obtained and compared to the spectra.
In one experiment, a contact probe with a central illumination fiber and two concentric rings of detection fibers (radii 0.1 and 1 mm), was placed in contact with the epithelium and used to measure spectra from ectocervix and endocervix. The influence of 5% acetic acid on fluorescence and reflectance spectra was also investigated. In another experiment, a single 100-micron fiber probe was placed perpendicular to a cut edge of tissue and scanned to measure spectra in depth. Depth scans were made over various areas of the cervix
Laser induced fluorescence is widely being developed as a new method for early detection of pre-cancerous tissue. Typically an optical fiber probe directly contacting tissue is used for detection and localization of abnormal tissue. This method of tissue interrogation has certain clinical and diagnostic restrictions due to physical contact with the tissue. This method of tissue interrogation has certain clinical and diagnostic restrictions due to physical contact with the tissue. The objective of our study was to investigate the method of remote sensing in colposcopy. The device was designed using an optical multichannel analyzer with UV excitation. The excitation light is delivered through the fiber bundle to the optical head that is attached to the colposcope. This arrangement allows one to conveniently collect fluorescence spectra from the cervix during regular colposcopy examination. To understand the practical restrictions of the remote sensing the influence of various factors are studied. A few modifications of the device were tested. Phantoms were created and used to test the device. Data form more than 200 patients shows substantial improvement in sensitivity and specificity compared with the doctor's impressions. The result of the experimental measurements of tissue-like phantoms and in- vivo measurements are provided. The modification increased the average signal/noise ration more than 4 times.