What factors affect signal intensity in MRI imaging?

Signal intensity in MRI imaging is influenced by several factors, including the type of tissue being imaged, the strength of the magnetic field, and the specific MRI sequences used (like T1 or T2 weighting). The presence of contrast agents can also enhance signal intensity by altering the relaxation times of tissues. Additionally, factors such as the patient's movement, coil sensitivity, and scan parameters (e.g., repetition time and echo time) can significantly affect the quality and intensity of the resulting images.