Electrical impedance tomography (EIT) is a low-cost noninvasive imaging method. The main purpose of this paper is to highlight the main aspects of the EIT method and to review the recent advances and developments. The advances in instrumentation and in the different image reconstruction methods and systems are demonstrated in this review. The main applications of the EIT are presented and a special attention made to the papers published during the last years (from 2015 until 2020). The advantages and limitations of EIT are also presented. In conclusion, EIT is a promising imaging approach with a strong potential that has a large margin of progression before reaching the maturity phase.

Introduction: Early detection of breast cancer saves lives. Existing detecting techniques are invasive. Electrical bioimpedance is a noninvasive technique and has a high diagnostic potential. Methods: An impedance value different from the normal can predict a physiological abnormality. The idea is to use a designed bioimpedance device to early detect breast cancer. A low-frequency current (1 kHz, 0.9 mA) is injected to each breast to measure the extracellular resistances. The resistances of the two breasts are then measured, and if there is a significant difference, warning is displayed. The performance was tested on a set of reference resistors, and the validation was done in vitro on (Na+Cl-) solutions and in vivo on a group of forty volunteer women. Results: The results confirm that the electrical conductivity of an ionic solution is proportional to its concentration. The concentration and the resistance are strongly correlated (correlation coefficient of 0.97). The accuracy and the repeatability of the measures were satisfactory. Early detection means that we can detect small extracellular concentration variations into the breast (from 0.6 g/l). In vivo measurements made it possible to set the threshold at 50 ohm. If the difference between the two measured breast resistances is greater than this threshold, we advise the patient to consult a doctor promptly. Conclusion: The difference between measured resistances of the right and left breast is a pertinent parameter to early detect the presence of a cancer. The lowest resistance value (RR or RL) can provide information on the breast affected by the cancer (right or left). Various improvements in the system are possible but already the results are encouraging. In the future, this system could be integrated into a bra.

Chitosan films are increasingly being applied in the biomedical field owing to their biocompatibility, biodegradability, non-toxicity, mucoadhesive nature, hemostatic properties, antibacterial and biological activities. This study aimed to enhance the mechanical properties of chitosan films by doping niosomal sage nanoparticles (NS-SagNPs) at various concentrations (100–300 μg). The NS-SagNPs were prepared by a thin-film hydration process with an average particle size of 21.5 nm. The doped chitosan films were fabricated through a simple casting method. FTIR and DSC measurements confirmed the successful incorporation of NS-SagNPs in the chitosan films. The mechanical properties of the doped films were improved and the most significant improvement was found in tensile strength and elasticity when the NS-SagNPs loading was increased to 300 μg. Based on these results, chitosan films doped with NS-SagNPs have the advantageous feature of sage and show enhanced mechanical properties compared with pure chitosan, rendering them more suitable for biomedical applications.