This thesis assesses an innovative hybrid technique to calibrate a microwave imaging (MWI) system combining synthetically emulated measured data with pre-simulated scenarios while retrieving a brain stroke condition. Stroke is a medical emergency that occurs when a vessel within the brain bursts or clots, causing the death of millions of cells per minute and requiring prompt diagnosis and treatment. Currently, clinicians support their appraisal on well-established image-based technologies such as magnetic resonance imaging (MRI) and computed tomography (CT). However, novel complementary technologies like MWI, a harmlessness, cost-effective, and non-bulky alternative, emerged in the last years. The calibration proposed here, attempts to ponder variations between the realized MWI antenna array elements caused by unavoidable manufacturing tolerances and placement compared to the nominal modeled electromagnetic (EM) scenario.