| Abstract [eng] |
Automated Identification of Cancerous Kidney Tissue by Application of Attenuated Total Reflection Infrared Spectroscopy It is possible to identify normal and cancerous tissues by applying the technique of an attenuated total reflection of infrared radiation (ATR IR) for the tissue analysis. It is possible to apply this technique immediately after surgery for the intercellular material of the removed tissues because this method does not require any special sample preparation. There is a need for methods that could automatically identify normal and cancerous tissues for the purpose to create the technique for the tissue recognition in vivo. The aim of this work is to create the system for the recognition of the cancerous kidney tissues. The goals of this study: 1. To register the ATR IR absorption spectra of intercellular material of the normal and tumorous human kidney tissue and to complement the database of the spectra. 2. To do the qualitative spectral analysis and identify the spectral markers and methods which could be used for the recognition system of the tissues. 3. To evaluate the accuracy of the different spectra recognition methods. 4. To evaluate the possibilities of the system for the tissue diagnostics in situ. Main results. After analysis of the ratio of the integral intensities of the spectral bands corresponding to the glycogen (1200 cm-1 - 950 cm-1) and Amide I of proteins (1717 cm-1 - 1591 cm-1), it was found that comparison of this ratio in normal and cancerous tissues is not an appropriate method for the recognition system. Using the attribute of spectra that the spectra of the intercellular material of normal and cancerous tissues have the different number of peaks in the glycogen area (1200 cm-1 – 950 cm-1) the program was written. It automatically identified the ATR IR absorption spectra of intercellular material of the normal and tumorous human kidney tissue. The program identified the cancerous tissue with 84 % accuracy, while the normal tissue was identified with 98 % accuracy. After creation of the spectra library containing ATR IR absorption spectra of 30 normal, 30 cancerous human kidney tissue samples, water and ethanol, there was written the program which operation algorithm is based on the comparison of the spectrum that is being analyzed with the spectra of the library. It was established that the latter method is the most appropriate for the tissue identification: the tissue of the clear cell renal cell carcinoma was identified with 90 % accuracy, while normal tissue was identified with 94 % accuracy. After evaluation of the validity of this method for the cancerous tissue diagnosis, it was established that the tissue type can be identified with 90 % sensitivity and 94 % specificity, while the positive and negative predictive values reached 93 % and 92 % respectively. It is possible that the normal human kidney tissue could be recognized with better accuracy according to the probable differences between ATR IR absorption spectra of intercellular fluid of the different kidney tissue areas. There is a need for the more detailed spectral analysis of different kidney parts. The applied methodology is able to classify the different types of tissue into several groups whereas the application of the fiber spectroscopic tool enables in situ tissue identification. This method after some improvements could be applied for the cancerous tissue diagnostics in the future. |
