Page 42 - TD-2-1

Tumor Discovery Breast cancer optical differentiation

2.7. Statistical analysis the significant differences among the various types of

So far, the commonly used methods to calculate the breast tissues and to select the optimum wavelength.
scattering and absorption properties of the various 2.8. System efficiency analysis
mediums are:
The efficiency of the presented system analysis methods is
(i) Monte Carlo (MC), which is a general class of achieved by comparing the outcomes with the histological
computational algorithms to achieve a numerical investigations. Regarding the results of these comparisons,
outcome by relying on random sampling. MC in the three numerical values (sensitivity, specificity, and accuracy)
optical field is effective for a broad range of light µa, could be measured to evaluate the various spectral analysis
µs, and photon paths . methods, as shown in Equations XIII, XIV, and XV:
[57]
(ii) Diffuse approximation (DA), which is an alternative
calculation method to calculate the scattering and Sensitivity = TP (XIII)
absorption properties of turbid mediums . TP FN+
[58]
(iii) IAD, which is an extended method from the adding
double (AD) method, and exploited to solve the TN
radiative transport equation in the optical field sector Specificity = TN FP+ (XIV)
related to the light’s interaction with the tissues in a
slab geometry .
[59]
The radiative transport equation could be used to
achieve light intensity distribution for the physical (XV)
mediums, as shown in Equation X . Where true positive (TP) is the cases detected by the
[60]
dI rs, ( ) s ) µ s p ss Ir sd, ( , ( proposed system as actual masses (tumors); false negative
ds =−(µ a + µ Ir s , ( ) + 4π ∫ ) ′ ) ′ θ (FN) is the cases of the system which had not been detected
and have masses; true negative (TN) is the cases detected
4π
(X) by the proposed system as normal, and they are normal
Where I (r,s) is the measured intensity per unit length, cases; and false positive (FP) is the cases mistakenly
r is the target location, s is the unit direction vector, detected by the presented system as abnormal masses, and
(
ps s, ′) is the phase function, and θ is the solid angle. they are normal cases.
Although there is no analytical solution for Equation X, 3. Results
it is achievable by exploiting the MC technique [61,62] . Our primary goal of these assessments is to investigate the
Moreover, the IAD method is used to solve the radiative optical properties of the ex vivo breast samples (normal/
transport equation. IAD technique and MC model have tumor) by identifying the spectral signatures through
offered more precise approximations of optical properties incorporating the HS camera capabilities to provide the
for the biological tissue (µ , µ , g) better than other methods. essential data for diagnostic and therapeutic applications
a
s
Two dimensionless quantities are exploited in the whole concerning breast cancer. We set up two diverse
process of the IAD, that is, the albedo (a) and the optical frameworks (reflection/transmission) methods using the
depth ( ), which are well-defined in Equations XI and XII: HS camera at wavelength range (400 ~ 1000 nm) and with
µ a polychromatic light source in the VIS-NIR range for this
a =� s (XI)
µ s +�µ a examination.
We initially exploited the first framework (reflection
µ
 = ( t µ s + ) (XII) method) to measure the investigated ex vivo breast tissue
�
a
sample’s light R ; one of the investigated cases is presented
d
Where is the sample’s thickness (mm), the measured in Figure 3. The solid red line represents the measured
values of R , the total diffuse transmittance (T ), and the tumor tissue’s R spectrum, and the solid blue line identifies
d
d
unscattered collimated transmittance (T) are applied to the normal tissue’s R spectrum over the VIS-NIR range.
d
c
the IAD process to calculate the (µ , µ ). d
a s From the measured light R for the investigated samples,
d
Due to the minimum computational time and high we could visually highlight the spectrum peaks, which
accuracy comparable to both DA and MC methods, we distinguish between the normal and the tumor tissues at
exploited in our system the IAD method for breast tissue wavelength range 600 ~ 680 nm and 750 ~ 960 nm at the
characterization and descriptive analysis (T-test) to verify VIS range and NIR range, respectively.
Volume 2 Issue 1 (2023) 7 https://doi.org/10.36922/td.258