PROCEEDINGS OF THE 7 INTERNATIONAL ... - Fizika

More documents

Recommendations

Info

M. Pučetaitė et al. / Medical Physics in the Baltic States 7 (2009) 96 - 99 monohydrate to 1324 cm -1 for calcium oxalate dihydrate (Fig. 3). The second issue in this study is related to distribution of chemical components in the cross-section of the stone. FTIR microscope was used for capturing of infrared image of cross-sectioned stones. The spectra from small areas of the cross section (100×100µm) were used for constructing false-colour images. Optical density Wavenumber, cm -1 600 800 1000 1200 1400 1600 1800 2000 Fig. 1. Spectrum of pure uric acid stone (top) compared with spectrum of uric acid from the library (bottom). Optical density 600 800 1000 1200 1400 1600 1800 2000 Wavenumber cm Fig. 2. Spectrum of urinary stone (top) constituted from calcium oxalate (black curve), carbapatite (blue curve) and struvite (red curve). -1 Optical density Optical density Wavenumber, cm -1 Wavenumber, cm -1 600 1000 1400 1800 1200 1300 1400 1500 Fig. 3. Spectra of stones containing calcium oxalate monohydrate (bottom) and calcium oxalate dihydrate (top). The band of the latter is shifted to the side of higher wavenumbers. The images were obtained by integrating area under specific spectral band. Having analyzed the data obtained, we divided the stones into two groups: the ones with some ordered distribution of chemical components and the others without any organized structure. One of the stones constituted of calcium oxalate and calcium phosphate (brushite) is shown in figure 4. Optical and false-colour images of this stone 97 are presented in figure 6. The false-colour image in the middle shows how calcium oxalate is distributed in the cross-section of the stone. Red colour corresponds the areas where the concentration of calcium oxalate is high and blue colour – where the concentration is low. The bottom image represents distribution of brushite. Having these images in mind, we can assume that the stone was induced by small deposit of brushite on the epithelium and the layer of calcium oxalate formed on it through time. Fig. 4. A photo of the stone constituted from calcium oxalate and calcium phosphate (brushite). A photo of another stone, constituted from calcium oxalate and calcium phosphate (carbapatite), is presented in figure 5. False-colour and optical images of this stone are shown in figure 6. Here we cannot see an organized structure, and the chemical compounds are distributed randomly in the cross-section of the stone. Fig. 5. A photo of the stone constituted of calcium oxalate and calcium phosphate (carbapatite). From this data, we can assume that both chemical components are distributed in the stone evenly what is resulted by simultaneous crystallization. In addition, there is no evidence that the stone formed on epithelium before it became loose. Most likely, the stone formed from oversaturated solution of the compounds.
M. Pučetaitė et al. / Medical Physics in the Baltic States 7 (2009) 96 - 99 4. Conclusions Conventional infrared spectroscopy, enhanced by KBr pellet technique, can be used to the qualitative and quantitative analysis of urinary stones. Even chemically rather similar components such as calcium oxalate monohydrate and calcium oxalate dehydrate give rice to very specific infrared absorption spectra. Accuracy of determination of relative concentration of some chemical component in the stone depends on abundance of the component. In case of major component (relative concentration more than 50%) Fig. 6. Optical (top image) and false-color images of the stone constituted from calcium oxalate (middle image) and brushite (bottom immage). Red color represents areas with high concentration of the chemical component and blue color – areas with low concentration or lack of the corresponding component. of the stone, the concentration can be defined with accuracy of 3%, while in case of minor component (relative concentration less than 5%) accuracy can be as low as 10%. Infrared spectroscopical mapping can be efficiently used for elucidating the distribution of chemical components in the stones. Due to disability to prepare urinary stone samples suitable for infrared transmission measurements, only reflection spectra can be used for the infrared mapping. One has two options here - either to use diffuse reflection spectroscopy or specular reflection spectroscopy. Our experience is that 98 diffusion reflection is difficult to use due to technical problems. Imaging by mapping requires using mapping stage incorporated to the diffusion sphere needed for such experiments. Such technical arrangement is hardly possible. Specular reflection measurements do not require the diffusion sphere and can be performed for the kidney stones fixed on mapping stage. Unfortunately the surface of polished kidney stone is rather porous what results to very weak signal of speculary reflected infrared light. Intensity of the signal depends on the size of illuminated area of the stone surface. Fig. 7. Optical (top image) and false-color images of the stone constituted from calcium oxalate (middle image) and carbapatite (bottom immage). Red color represents areas with high concentration of the chemical component and blue color – areas with low concentration or lack of the corresponding component. Theoretically, infrared microscopy allows diminish this area almost to diffraction limit - 10×10µm. In practice, due to weakness of the signal of specular reflection from polished kidney stones this area cannot be smaller than 100×100 µm. This limitation seems not to be critical for studies of distribution of chemical components in urinary stones. Chemical images obtained in this work show that in case of ordered structure of the stones the components have domain structure and the domains are big enough to be characterized by infrared specular reflection microscopical technique. Spectra collected by specular
Page 1 and 2:
2009 PROCEEDINGS OF THE 7 th INTERN
Page 3 and 4:
Executive editor: D.Adlienė CONFER
Page 5 and 6:
11.15-11.30 Daiva Leščiute, Valda
Page 7 and 8:
MEDICAL PHYSICS IN THE BALTIC STATE
Page 9 and 10:
S. Mattsson / Medical Physics in th
Page 11 and 12:
S. Mattsson / Medical Physics in th
Page 13 and 14:
L. Bumbure et al. / Medical Physics
Page 15 and 16:
Average brightness Brightness range
Page 17 and 18:
Page 19 and 20:
D. Lesciute et al. / Medical Physic
Page 21 and 22:
Page 23 and 24:
D. Kaskelyte et al. / Medical Physi
Page 25 and 26:
Page 27 and 28:
V. Poderys et al. / Medical Physics
Page 29 and 30:
E D A B C V. Poderys et al. / Medic
Page 31 and 32:
Page 33 and 34:
A. Kulbickas / Medical Physics in t
Page 35 and 36:
Page 37 and 38:
M. Franckevicius / Medical Physics
Page 39 and 40:
M. Franckevicius / Medical Physics
Page 41 and 42:
J. Puiso et al. / Medical Physics i
Page 43 and 44:
J. Puiso et al. / Medical Physics i
Page 45 and 46:
T. Landberg et al. / Medical Physic
Page 47 and 48: T. Landberg et al. / Medical Physic
Page 53 and 54: MEDICAL PHYSICS IN THE BALTIC STATE
Page 55 and 56: S. Plaude et al. / Medical Physics
Page 59 and 60: Table 1. Optimization of number of
Page 63 and 64: C.-M. Nilsson / Medical Physics in
Page 67 and 68: S. Bernhardsson et al. / Medical Ph
Page 69 and 70: S. Bernhardsson et al. / Medical Ph
Page 71 and 72: 2.3. Biological test. Y. Dekhtyar e
Page 75 and 76: Scatter dose ( Gy /mA s) 1.55E-12 1
Page 79 and 80: N. Kazuchits et al. / Medical Physi
Page 81 and 82: V. Minialga et al. / Medical Physic
Page 83 and 84: Temperature, o C 36 35 34 33 32 31
Page 85 and 86: O. Klepalov et al. / Medical Physic
Page 89 and 90: G. Adlys / Medical Physics in the B
Page 91 and 92: G. Adlys / Medical Physics in the B
Page 93 and 94: D. Mikšys / Medical Physics in the
Page 95 and 96: L. Krynke et al.. / Medical Physics
Page 97: MEDICAL PHYSICS IN THE BALTIC STATE
Page 105 and 106: D. Bernatavičius et al. / Medical
Page 109 and 110: N. Vaiciunaite / Medical Physics in
Page 111 and 112: D. Adlienė et al. / Medical Physic
Page 113 and 114: MP Competences Generic Competences
Page 117 and 118: S. Tabakov et al. / Medical Physics
Page 119 and 120: J. Laurikaitienė et al. / Medical
Page 121 and 122: R, % 100,0 99,5 99,0 98,5 98,0 97,5
Page 123 and 124: S. Mockevičienė et al. / Medical
show all

PROCEEDINGS OF THE 7 INTERNATIONAL ... - Fizika

Create successful ePaper yourself

Delete template?

Save as template?