HRCT stands for High-Resolution Computed Tomography. This is performed on a technically advanced CT (Computerised x-ray) machine and gives the doctor excellent details of normal and diseased tissue. For the lungs it almost always involves using intravenous injection of x-ray contrast medium as well, to identify normal and abnormal blood vessels. The cost varies from Rs. 2000-6000. Radiation exposure is within safe limits except in pregnancy.