1. in the human tissue research
Positronium probe
in the human tissue research
Bożena Zgardzińska
Institute of Physics, Maria Curie-Sklodowska University, Lublin, Poland

2. Positron and positronium probe
free annihilation
vacuum e+
+ e-
p-Ps τ=125 ps e+ e-
hydrogenlike Ps atom
o-Ps τ=142 ns e+ e-

3. Positron and positronium probe
free annihilation
vacuum e+
+ e-
p-Ps τ=125 ps e+ e-
hydrogenlike Ps atom
o-Ps τ=142 ns e+ e-
The o-Ps lifetime depends on the free volume size
- the larger is volume the longer is o-Ps lifetime
medium
τ=1÷10 ns
pick-off process

4. Positron and positronium probe
Positron annihilation lifetime spectroscopy (PALS) τ2
free annihilation
vacuum e+
+ e-
p-Ps τ=125 ps e+ e- τ1
hydrogenlike Ps atom
o-Ps τ=142 ns e+ e- τ3
The o-Ps lifetime depends on the free volume size
- the larger is volume the longer is o-Ps lifetime
medium
τ=1÷10 ns
pick-off process

5. Positronium probe
The PALS technique use the Ps probe to determine the free volume size in the medium.
Succesfully applied in studies of many classes of materials (organics, polymers, porous materials, etc.)
Useful for the human tissue investigation?

6. Sample 46 samples from 20 patients
Cardinal S. Wyszyński Provincial Specialist Hospital in Lublin
in 20% of population of women over 35 years, uterine myomas are diagnosed
clinical examination,
symptoms, history , USG
recommended surgical removal of the uterus
sample chamber
the surgeon cuts fragments of healthy and „sick” tissues for the PALS measurements
46 samples from 20 patients
sample in formaline
22Na source

7. fast – slow spectrometer
Technical data
Temperature: 21oC
Spectrometer: single Gaussian, resolution ps
Time: 1,5 h
Statistics: about 1,6*106cc/spectrum
fast – slow spectrometer
sample chamber
46 samples from 20 patients
sample in formaline
22Na source

8. Methodology 46 samples from 20 patients
Consent of the Bioethical Commission
A procedure was developed for:
sampling,
transporting samples,
handling samples during the measurement and after the measurement,
disinfection procedures for chambers and tools.
Minimum two samples were taken from each patient, which the surgeon classified (looking at the samples) as healthy tissue and diseased tissue.
The result is a set of data pairs in which a sample of healthy tissue is a reference to a diseased sample.
46 samples from 20 patients

9. PAL spectra parameters
PAL spectra parameters for pure water at 21oC (deionized water):
τ1=0,265 ns, I1=43,6%
τ2=0,521 ns, I2=31,2%
τ3=1,902 ns, I3=25,2%
Human body is in 45-70% water.
The human tissue PAL spectra have three components.
Previously we have investigated these microcapsules as a function of temperature. What we learned about the material from these measurements? Based on existing results we were able to establish that in the microcapsules two o-Ps components are visible (with a distinguishable lifetimes). The longer of the lifetimes we assigned to the filling material, the shorter one – to the shell material. Analysis of the PALS parameters had shown that the core material occurs in three phases: rigid crystal, rotator and liquid. At 25 C the microcapsules absorb the energy from the enviorment until the core become molten. The effect of energy absorption is also visible at -4 C when the core material transforms from a rigid to a rotator phase.
We also have identified the filler material (in spite of patent protection of this information by manufacturer).
It was found that the filler material is 75% of the total weight of the microcapsules, the remainder is the shell material (this result also confirmed two other methods).
Now, because the microcapsules are used in the building industry, we decide to investigate their behavior as a function of pressure (it seems to be important from the viewpoint of possible applications).

10. PALS results τ3=1,902 ns The values of PALS parameters
I3=25,2%
The values of
PALS parameters
differ from those
obtained for
water. The results
for healthy
tissues are
different for
different patients
and therefore a
common reference level for PALS studies can not be established. Patients indicated in this part of the picture were diagnosed as having uterine fibroids.
Previously we have investigated these microcapsules as a function of temperature. What we learned about the material from these measurements? Based on existing results we were able to establish that in the microcapsules two o-Ps components are visible (with a distinguishable lifetimes). The longer of the lifetimes we assigned to the filling material, the shorter one – to the shell material. Analysis of the PALS parameters had shown that the core material occurs in three phases: rigid crystal, rotator and liquid. At 25 C the microcapsules absorb the energy from the enviorment until the core become molten. The effect of energy absorption is also visible at -4 C when the core material transforms from a rigid to a rotator phase.
We also have identified the filler material (in spite of patent protection of this information by manufacturer).
It was found that the filler material is 75% of the total weight of the microcapsules, the remainder is the shell material (this result also confirmed two other methods).
Now, because the microcapsules are used in the building industry, we decide to investigate their behavior as a function of pressure (it seems to be important from the viewpoint of possible applications).
histopathology photo
Smooth muscle tissue of the uterine wall and sections of blood vessels

11. PALS results Muscle cell leukemia with focal fibrosis and glazing
However, correlating the results obtained for healthy and diseased tissue, one can find trends that allow for initial inference based on the PALS measurements, what kind of tissues we have.
Muscle cell leukemia with focal fibrosis and glazing and sections of blood vessels

12. PALS results
PALS studies were carried out not only on healthy and uterine tissues, but also on other types of tissues, including on endometrium tissues and tissues from the oviduct and ovary. The lines delimit these types of tissues.

13. PALS results Focal fibrosis Leiomyoma
Smooth muscle tissue of the endometrium wall

14. PALS results
atrophic
growing
Endometrium

15. PALS results
oviduct
Ovary with cyst

16. Conclusions Using the PALS technique:
- the different type of tissue can be identify
the normal and abnormal tissue can be detected

17. Thank you for your attention
Institute of Physics, Maria Curie-Sklodowska University, Lublin, Poland