Tumor segmentation via enhanced area growth algorithm for lung CT images

Abstract Background Since lung tumors are in dynamic conditions, the study of tumor growth and its changes is of great importance in primary diagnosis. Methods Enhanced area growth (EAG) algorithm is introduced to segment the lung tumor in 2D and 3D modes on 60 patients CT images from four different databases by MATLAB software. The contrast augmentation, color intensity and maximum primary tumor radius determination, thresholding, start and neighbor points’ designation in an array, and then modifying the points in the braid on average are the early steps of the proposed algorithm. To determine the new tumor boundaries, the maximum distance from the color-intensity center point of the primary tumor to the modified points is appointed via considering a larger target region and new threshold. The tumor center is divided into different subsections and then all previous stages are repeated from new designated points to define diverse boundaries for the tumor. An interpolation between these boundaries creates a new tumor boundary. The intersections with the tumor boundaries are firmed for edge correction phase, after drawing diverse lines from the tumor center at relevant angles. Each of the new regions is annexed to the core region to achieve a segmented tumor surface by meeting certain conditions. Results The multipoint-growth-starting-point grouping fashioned a desired consequence in the precise delineation of the tumor. The proposed algorithm enhanced tumor identification by more than 16% with a reasonable accuracy acceptance rate. At the same time, it largely assurances the independence of the last outcome from the starting point. By significance difference of p < 0.05, the dice coefficients were 0.80 ± 0.02 and 0.92 ± 0.03, respectively, for primary and enhanced algorithms. Lung area determination alongside automatic thresholding and also starting from several points along with edge improvement may reduce human errors in radiologists’ interpretation of tumor areas and selection of the algorithm’s starting point. Conclusions The proposed algorithm enhanced tumor detection by more than 18% with a sufficient acceptance ratio of accuracy. Since the enhanced algorithm is independent of matrix size and image thickness, it is very likely that it can be easily applied to other contiguous tumor images. Trial registration PAZHOUHAN, PAZHOUHAN98000032. Registered 4 January 2021, http://pazhouhan.gerums.ac.ir/webreclist/view.action?webreclist_code=1930

Molybdenum transmutation via

99mTc is the usual medical isotope for imaging in nuclear medicine. The use of accelerators to produce 99Mo is an alternative to nuclear reactors. Here, the neutron production from a new neutron source is investigated to achieve a proper production yield. The induced neutron was simulated from 30 MeV protons on a beryllium target. The Adiabatic Resonance Crossing (ARC) method was evaluated using lead and bismuth moderators, and lead(II) fluoride reflector around a moderator region. The flux and energy of the aggregated neutrons within different regions of the proposed activator were estimated by the MCNPX code. The epithermal flux in the reflector region was greater than that in the moderator region, since the maximum amount was estimated to be $6.00\text{E}+11\ \text{n/cm}^{2}\text{/s}$ when the bismuth moderator was employed. The outcomes demonstrated that the production yield of 99Mo improved using the bismuth material, whereas the 98Mo sample at a distance $z = -38\ \text{cm}$ from the target showed a greater amount by 5.03E + 5 MBq through a 0.1 cm sample thickness. When the sample was positioned in the reflector region, the obtained yield increased taking advantage by the more accumulated flux in the epithermal range. The ARC method can replace conventional reactor-based prototypes of the 99Mo-99mTc generator, or complement them, because it is safe and more accessible

Estimation of microvascular capillary physical parameters using MRI assuming a pseudo liquid drop as model of fluid exchange on the cellular level

AimOne of the most important microvasculatures’ geometrical variables is number of pores per capillary length that can be evaluated using MRI. The transportation of blood from inner to outer parts of the capillary is studied by the pores and the relationship among capillary wall thickness, size and the number of pores is examined.BackgroundCharacterization of capillary space may obtain much valuable information on the performance of tissues as well as the angiogenesis.MethodsTo estimate the number of pores, a new pseudo-liquid drop model along with appropriate quantitative physiological purposes has been investigated toward indicating a package of data on the capillary space. This model has utilized the MRI perfusion, diffusion and relaxivity parameters such as cerebral blood volume (CBV), apparent diffusion coefficient (ADC), ΔR2 and [[mml:math altimg="si1.gif"]][[mml:mrow]][[mml:mi]]Δ[[/mml:mi]][[mml:msubsup]][[mml:mi]]R[[/mml:mi]][[mml:mn]]2[[/mml:mn]][[mml:mo]]*[[/mml:mo]][[/mml:msubsup]][[/mml:mrow]][[/mml:math]] values. To verify the model, a special protocol was designed and tested on various regions of eight male Wistar rats.ResultsThe maximum number of pores per capillary length in the various conditions such as recovery, core, normal-recovery, and normal-core were found to be 183±146, 176±160, 275±166, and 283±143, respectively. This ratio in the normal regions was more than that of the damaged ones. The number of pores increased with increasing mean radius of the capillary and decreasing the thickness of the wall in the capillary space.ConclusionDetermination of the number of capillary pore may most likely help to evaluate angiogenesis in the tissues and treatment planning of abnormal ones

Radioanalytical prediction of radiative capture in 99Mo production via transmutation adiabatic resonance crossing by cyclotron

In this study, the transmutation adiabatic resonance crossing (TARC) concept was estimated in Mo-99 radioisotope production via radiative capture reaction in two designs. The TARC method was composed of moderating neutrons in lead or a composition of lead and water. Additionally, the target was surrounded by a moderator assembly and a graphite reflector district. Produced neutrons were investigated by (p,xn) interactions with 30 MeV and 300 mu A proton beam on tungsten, beryllium, and tantalum targets. The Mo-99 production yield was related to the moderator property, cross section, and sample positioning inside the distinct region of neutron storage as must be proper to achieve gains. Gathered thermal flux of neutrons can contribute to molybdenum isotope production. Moreover, the sample positioning to gain higher production yield was dependent on a greater flux in the length of thermal neutrons and region materials inside the moderator or reflector. When the sample radial distance from Be was 38 cm inside the graphite region using a lead moderator design, the production yield had the greatest value of activity, compared with the other regions, equal to 608.72 MBq/g. Comparison of the two designs using a Be target revealed that the maximum yield occurred inside the graphite region for the first design at 38 cm and inside the lead region for the second design at 10 cm. The results and modeling of the new neutron activator were very encouraging and seem to confirm that the TARC concept can be used for Mo-99 production in nuclear medicine