But the MRI machine can do a more thorough investigation is less time with less inconvenience to the patient and with fewer medical staff. The colonoscopy I had essentially occupied a doctor and a nurse for close to half an hour. The MRI that I had more recently for the same purpose took one radiologist and the part involving me was over in less than fifteen minutes.
And the capital cost of the machine is not necessarily the relevant measure. If the MRI machine is idle then it is wasting money so if you have one it should be used as much as possible which means that the marginal cost of the MRI might well compete with colonoscopy.
I have also read that many colonoscopy patients, especially in the US, require sedation which of course is not necessary with MRI.
And the capital cost of the machine is not necessarily the relevant measure. If the MRI machine is idle then it is wasting money so if you have one it should be used as much as possible which means that the marginal cost of the MRI might well compete with colonoscopy.
I have also read that many colonoscopy patients, especially in the US, require sedation which of course is not necessary with MRI.