Spinal hernia tissue autofluorescence spectrum.

The laser intervertebral disc decompression may provide appropriate relief in properly selected patients with contained disc herniations. The present investigation aims to characterise intervertebral disc material by autofluorescence induced by laser light. Degeneration of the intervertebral disc is associated with progressive biochemical changes in disc material. Percutaneous laser disc decompression has become rather popular for the treatment of lumbar disc herniation, but there are problems in the selection of patients. For this purpose, recognition of the disc composition is necessary. We propose a new type of spectroscopic investigation. It is advantageous to the characterization of intervertebral disc material. Intervertebral disc specimens were removed during open surgery from different disc locations. Preoperative patients' MRI was evaluated using the Pfirrmann disc degeneration and Komori scale for migrating of herniated nucleus pulposus. Adjacent slices of stained disc sections were evaluated by histology/histochemistry and autofluorescence spectra. Comparison of the MRI, spectral, histological and histochemical data was performed. The MRI Komori scale correlated with the histology Boos degeneration index. In the histochemistry, collagens other than collagens I and II of the disc were distinguished with best positive correlation coefficient (0.829) and best negative one (-0.904) of proteoglycans of sequester to Boos index. A correlation of the IV Gaussian component of the hernia spectra with the Boos index was established. The Gaussian component correlation with different collagen types and proteoglycan was determined for the disc and sequester. "Autofluorescence-based diagnosis" refers to the evaluation of disc degeneration by histological and histochemical evaluation; it can provide additional data on the degeneration of an intervertebral disc.

Cervical smear photodiagnosis by fluorescence.

OBJECTIVE: Fluorescence is widely investigated and can characterize general changes occurring in the state of the cell and the tissue during physiological and/or pathological processes, but the method has not been adopted for clinical use. We present a photodiagnostic device and a relevant evaluation method fitted to classical screening procedures. This method is based on the discovery of smear content intrinsic fluorescent markers. BACKGROUND DATA: Meaningful spectral components of cervical smear samples differ from those measured in the entire live cervix. This article deals with the identification of changes in smear spectra in cervicitis and CIN2+ (cervical intraepithelial neoplasia of the second degree or higher) at 355 nm excitation. METHODS: Methods used in the study: microlaser-induced fluorescence spectroscopy of liquid cytology samples and histological evaluation of the biopsies of the same cervix (and/or only cytological evaluation) was performed for 78 cases. The fluorescence spectra of cervical cytology supernatant sediment were approximated with several Gaussian components. The ratios of the area under each Gaussian component to the whole area under the experimental curve were calculated and compared among histological groups by using the Mann-Whitney test and receiver operating characteristic (ROC) analysis. RESULTS: The results of this study are a concise summary of the essential features verified by the data: the spectral regions 402-416 nm and 424-438 nm are important for the discrimination of both normal and CIN2+ groups (in terms of sensitivity, specificity, and positive predictive value). The spectral regions 480-515 nm and 595-625 nm are important for the identification of cervicitis. CONCLUSIONS: Cervical smear autofluorescence diagnostics could be useful for cancer screening at the point of care, in a simple cytology laboratory, and for the monitoring of treatment. We suggest possible fluorophores in the smear content.

Methods for detailed histopathological investigation and localization of biopsies from cervix uteri to improve the interpretation of autofluorescence data.

Fluorescence spectroscopy is one of many optical methods that are potentially clinically useful for noninvasive detection and characterization of disorders on the cervical part of uterus, including precancerous lesions. The cervix uteri exhibits a biologically complex tissue and the morphology of a biopsy is generally not homogenous. The standard histopathological protocol accounts only for the most severe condition found within the biopsy and no information is given on other constituents potentially influencing the recorded fluorescence spectra. Spectra are usually correlated, using multivariate techniques, to the histopathological diagnosis of the biopsies. Since the probe volume of fluorescence spectroscopy is considerably smaller than the extension of the biopsy, this can cause problems in the search for correlation between the fluorescence signals and the pathological structures. In addition, the orientation and location of the biopsies are normally not recorded. We now report on the first detailed histopathological protocol where numerous tissue parameters, such as thickness and type of the epithelium and the number of blood vessels, glands, and inflammatory cells, are tabulated and the orientation and location of the biopsy are recorded as precisely as possible. Hopefully, the use of this protocol together with sophisticated mathematical methods will increase the probability to classify cervical disorders of the uterus, including precancerous lesions, with high sensitivity and specificity.