Radiation Biology, Radiotherapy & Radiodiagnosis - Scholarly Publications

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Browsing Radiation Biology, Radiotherapy & Radiodiagnosis - Scholarly Publications by Subject "Research Subject Categories::MEDICINE"

Now showing 1 - 4 of 4
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    Open Access
    Evaluation of temperature distributions during microwave ablation of ex vivo bovine liver using two types of antennas.
    (2019-03) Ibitoye, AZ; Nwoye, EO; Saseyi, AO; Adeneye, SO; Adedokun, MB; Aweda, MA
    Introduction: Temperature distributions during microwave ablation are dependent on the antenna types, antenna geometry, tissue properties, input power and ablation. All these factors can significantly affect the coagulation region, ablation length, ablation diameter, aspect ratio, backward heating (comic effect), and degree of necrosis. Temperature distributions during microwave ablation procedures determine the effectiveness of ablating tumours in tissue. Objective: The aim of this study is to evaluate temperature distributions during microwave ablation using sleeved and dual slot antennas. Materials and Methods: In this study, sleeved and dual slot antennas were designed using COMSOL MULTIPHYSICS software version 4.4. Temperature distributions were analyzed at 10 mm and 20 mm from the antennas’ surfaces. Dualslot and sleeved antennas were fabricated from 0.085’ 50 Ω semi-rigid coaxial cable to conform to numerical simulation. The antennas were applied on ex vivo bovine liver. Thermometer probes were placed at 10 mm and 20 mm from the antennas’ surfaces with the input powers set at 30, 50 and 80 W for 300 s. Before each ablation, the initial temperature was recorded whereas subsequent measurements were recorded at 50 s intervals. Numerical simulation and experimental obtained data were analyzed and compared using the student's t-test statistical tool. Results: The findings in this study showed that temperatures produced at the two points of measurements by the sleeved antenna were greater than that of the dual-slot antenna in simulation and experimental procedures. Also, there was no significant difference between simulation and experimentally results for dual-slot antenna and sleeved antenna (p = 0.25). Conclusion: In conclusion, the sleeved antenna has the potential to ablate a tumour faster above the tumoricidal temperatures at the same position than the dual-slot antenna.
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    Open Access
    Evaluation of the performance of designed coaxial antennas for hyperthermia using simulation and experimental methods
    (Sciendo, 2021-03-31) Ibitoye, AZ; Ogese, CO; Adedokun, MB; Habeebu, MYM; Nwoye, EO; Aweda, MA
    Introduction: Antenna geometries and tissue properties affect microwave energy distributions during microwave ablation procedures. There is a paucity of information on the potential of antenna fabricated from a thick semi-rigid coaxialcable in the field of microwave thermal therapy. This study aimed at comparing the performance of two dual-slotantennas designed from different semi-rigid coaxial cables for the ablation of a liver tumour using numerical simulationand experimental validation methods. Materials and Methods: COMSOL Multiphysics software was used for designing dual-slot antennas and as well as toevaluate microwave energy deposition and heat distribution in the liver tissue. Experimental validations were conductedon the ex-vivo bovine livers to validate the simulation results. Results: Thick antenna developed in this study produced a higher sphericity index, larger ablation diameter and reducedbackward heating along the antenna shaft than the existing one. The experimental validation results also indicatesignificant differences between the two antennas in terms of ablation diameters (p = 0.04), ablation lengths (p = 0.02)and aspect ratios (p = 0.02). Conclusion: Based on the findings in this study, an antenna fabricated from a thick coaxial cable has ahigher potential oflocalizing microwave energy in the liver than conventional antennas.
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    Open Access
    Overexposure of rats to radiation from infrared lamp: Effects on blood parameters
    (Wolters Kluwer, 2016-07) Ibitoye, A; Afolabi, O; Irurhe, N; Ekun, O; Sowunmi, A
    Background: Previous reports showed that infrared radiation (IR) involved in photoaging, photocarcinogenesis, free radicals’ production, and depletion of bone marrow cells. Beneficial effects of moderate exposure to infrared lamp have been itemized to include enhancement of blood circulation, relief from muscular pain, and wound healing acceleration with scarce information on biological effects when it is overexposed. Therefore, there is a need to investigate the possibility of its overexposure on the biological system, especially blood parameters. Aim: This study was aimed to determine the biological effects of overexposure to radiation from infrared lamp on blood parameters. Materials and Methods: Infrared lamp of 100 W acts as a source of the IR. Twenty male healthy Wistar rats of the age range between 10 and 12 weeks and weigh between 100 and 250 g were studied. All the animals studied also acts as a control group with their blood samples taken and recorded as initial counting values. The animals were later divided into three groups: A, B, and C according to their hours of exposure according to their weight. Animals in Groups A, B, and C were exposed to IR for 1, 3, and 5 h, respectively. Blood samples of each animal in the group were taken 24, 48, and 96 h after exposure. The total number of erythrocytes, leukocytes, lymphocyte, and neutrophils were counted and compared with the initial samples. Results: The results revealed that packed cell volume, white blood cells, and lymphocytes of all the exposed animals averagely decreased by 17.4%, 17.5%, and 11.3%, respectively, whereas neutrophil increased by 19.0% after exposure to infrared. Conclusion: This study established that overexposure to radiation from infrared lamp affects hematological parameters.
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    Open Access
    Synthesis and Characterization of Iron Oxide Nanoparticles from Wonderful Kola seed for Future Application in Microwave Tumour Ablation
    (Academic Journals, 2021-08) Morakinyo, AD; Ibeh, JG; Aweda, MA; Adeyemi, DK; Oyenenin, AO; Ige, O; Ibitoye, AZ; Adeneye, SO
    The green method of synthesizing nanoparticles is an eco-friendly, reliable and cost effective approach which has proven to be an alternative to chemical based methods over the years (Dipankar and Murugan, 2012). This research focuses on the synthesis and characterization of super-paramagnetic iron oxide nanoparticles (FeNPs), adopted a co-precipitation procedure by the interaction of ferric chloride solution (precursor) with aqueous extract of wonderful kola seed. The characterization phase was investigated using the Ultra-violet visible spectroscopy, Fourier Transform Infra- red, X-ray Diffraction and Scanning Electron Microscopy. The SEM analysis showed that the particles have irregular shapes with the average particle diameter measured between 10 to 40 nm. The crystalline nature of the nanoparticles was confirmed by the X-ray diffraction method with the crystallite size range between 10 and 47 nm. The absorbance peak of the synthesized wonderful kola FeNPs was investigated using the ultra-violet visible spectroscopy with wavelengths of 431, 488, 613 and 642 nm and corresponding band gap energies of 2.87, 2.54, 2.02 and 1.93eV respectively; while the absorbance peak of wonderful kola extract has a wavelength of 256 nm with band gap energy of 4.84 eV showing the tendency of a new compound formed. The FTIR peak at 3336.0cm-1 corresponds to the –OH bond stretching, with a strong and broad peak intensity (S, B) indicating the presence of alcohols and phenol. The peak value at 1636.3 cm-1 corresponds to C=O bond stretching vibration with strong intensity, indicating the presence of carbonyl and acids. The peak values also denote the change in fundamental vibrational levels of most molecules present in the sample. The synthesized magnetic nanoparticles could be applied as an enhancement tool in microwave tumour ablation.