What are the factors that increase Peripheral Nerve Stimulation (PNS)?

The factors that increase Peripheral Nerve Stimulation (PNS) include the duty cycle, rise time, and maximum gradient. All of these elements relate to how the magnetic field gradients are applied during an MRI procedure.

The duty cycle refers to the ratio of the time the gradient is turned on to the total time of the sequence. A higher duty cycle means that the gradients are applied for a longer period, which can lead to increased stimulation of peripheral nerves due to sustained magnetic fields.

Rise time is the time it takes for the gradient to go from zero to its maximum amplitude. Shorter rise times can produce sharper changes in the magnetic field, and rapid changes can stimulate nearby nerves, increasing the risk of PNS.

The maximum gradient is related to the strength of the magnetic field changes applied. Higher maximum gradients can induce stronger electrical fields in the body, elevating the likelihood of nerve stimulation.

Considering all these factors together, it's clear that duty cycle, rise time, and maximum gradient collectively contribute to the risk of inducing PNS, making the choice indicating all of the above the correct answer.