Primary Aldosteronism (PA) has been recognised as a curable cause of hypertension, which affects more than 18% of hypertensive patients. In PA, excess aldosterone is secreted by the adrenal glands in the body due to a tumour (adenoma). Increased aldosterone results in increased reabsorption of sodium and water from urine in the kidneys, leading to high blood pressure (hypertension). It is proposed to treat PA with a novel Microwave Ablation (MWA) system delivered via a flexible endoscope to access the adrenal gland. This undergraduate summer research project will focus on the assessment of heat damage from microwaves to the ablated adrenal tissue in the pre-clinical evaluation of the proposed MWA based treatment of PA. A microwave ablation system has been developed at sponsor’s research laboratory which is being evaluated for safety and technical merits. In the first stage, the system will be tested on excised samples of bovine and porcine adrenal glands with a range of radiation doses to assess the effective ablation zone. Thermal damage in central and peripheral ablation zones will be assessed by immunohistochemical staining. The results of this project will be used in optimising the design of the MWA system.