Imaging strategies to reduce the risk of radiation in CT studies, including selective substitution with MRI

Abstract

“When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others.” Bertrand Russell (1872–1970) Computed tomography (CT) is one of the largest contributors to man‐made radiation doses in medical populations. CT currently accounts for over 60 million examinations in the United States, and its use continues to grow rapidly. The principal concern regarding radiation exposure is that the subject may develop malignancies. For this systematic review we searched journal publications in MEDLINE (1966–2006) using the terms “CT,” “ionizing radiation,” “cancer risks,” “MRI,” and “patient safety.” We also searched major reports issued from governmental U.S. and world health‐related agencies. Many studies have shown that organ doses associated with routine diagnostic CT scans are similar to the low‐dose range of radiation received by atomic‐bomb survivors. The FDA estimates that a CT examination with an effective dose of 10 mSv may be associated with an increased chance of developing fatal cancer for approximately one patient in 2000, whereas the BEIR VII lifetime risk model predicts that with the same low‐dose radiation, approximately one individual in 1000 will develop cancer. There are uncertainties in the current radiation risk estimates, especially at the lower dose levels encountered in CT. To address what should be done to ensure patient safety, in this review we discuss the “as low as reasonably achievable” (ALARA) principle, and the use of MRI as an alternative to CT. J. Magn. Reson. Imaging 2007;25:900–909. © 2007 Wiley‐Liss, Inc.

Whole-body MRI: comprehensive evaluation on a 48-channel 3T MRI system in less than 40 minutes. Preliminary results

“…Additionally, there has been progress in the development of other whole-body imaging modalities, such as whole-body CT, PET, and PET/CT. Recently, however, an increasing awareness of the risks of ionizing radiation exposure has encouraged the investigation of alternative imaging techniques (1,2) . mote control of table motion, together with interconnection of multiple multichannel phased-array coils, has improved the spatial resolution and speed of data acquisition, and rendered whole-body MRI diagnostically accurate and fast (3)(4)(5) .…”

Whole‐body MRI for staging Hodgkin lymphoma in a pregnant patient

“…Subsequent ultrasound-guided core-needle biopsy of the lymph node revealed nodular sclerosing Hodgkin lymphoma (HL). Combined 18 F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is the standard imaging modality for staging HL, but uses ionizing radiation which is potentially harmful to the unborn fetus [1,2]. Therefore, whole-body magnetic resonance imaging (MRI) was used instead as a radiation-free alternative [2,3].…”

“…Combined 18 F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) is the standard imaging modality for staging HL, but uses ionizing radiation which is potentially harmful to the unborn fetus [1,2]. Therefore, whole-body magnetic resonance imaging (MRI) was used instead as a radiation-free alternative [2,3]. The whole-body MRI examination, which consisted of coronal T1-weighted and coronal short inversion time inversion recovery (STIR) acquisitions, took 30 min and was well tolerated by the patient.…”

“…is the standard imaging modality for staging HL, but uses ionizing radiation which is potentially harmful to the unborn fetus [1,2]. Therefore, whole-body magnetic resonance imaging (MRI) was used instead as a radiation-free alternative [2,3].…”

“…Therefore, whole-body magnetic resonance imaging (MRI) was used instead as a radiation-free alternative [2,3]. The whole-body MRI examination, which consisted of coronal T1-weighted and coronal short inversion time inversion recovery (STIR) acquisitions, took 30 min and was well tolerated by the patient.…”