Prostate MR is the imaging of prostate gland using magnetic resonance (MR) or magnetic resonance imaging (MRI) technology. The MR scanner, a large magnet, is used to create images of various tissues in the body that a Radiologist can use to diagnose abnormalities. In order to intensify the signals and improve the clarity of these images, several variations of MR coils are sometimes used. These MR coils can be placed on the surface of the body, e.g. a torso or pelvic MR coil, or inserted into a body orifice, e.g. an endorectal coil.
Prostate MR can be done with just a torso/pelvic coil or with a combination of an endorectal coil and a torso/pelvic coil. Endorectal Prostate MR offers excellent image quality due to the proximity of the coil to the gland and can best help in cancer diagnosis and treatment planning.
MRI provides excellent image quality for a more accurate look at the prostate gland. MRI uses magnetic fields to image the gland. This superior resolution offered by MRI can enable physicians to guide biopsies, determine cancer stage, conclude whether the cancer is contained within the gland or has spread, and determine treatment path for the patient.
Prostate MR can be particularly useful in following cases:
- When a patient has an increasing PSA level and a negative biopsy, the detailed information provided by MRI can lead the doctor to the area most suspicious for disease, increasing the chance of obtaining a comprehensive biopsy.
- An MRI can help determine cancer stage by differentiating between a cancer that is within the prostate and a cancer that has spread beyond the prostate. However, be aware that the false positive and false negative rates are about 30%.
- Patients who have a rising PSA after radical prostatectomy might benefit from an MRI to determine if cancer has recurred in the prostate bed.
- An MRI can be beneficial for planning a patient’s radiation treatment therapy since it’s important that the radiation is targeted to only the affected area. However, a CAT scan usually provides sufficient information and is less expensive.
Prostate MR uses advanced magnetic resonance imaging to create very accurate and clear images of the prostate gland. These images are diagnostic quality and are especially useful to clinicians when diagnosing prostate diseases. Additionally, medical images resulting from prostate MR can be combined with powerful post-processing computer programs to enable very detailed information about the prostate. This information can provide a wider variety of diagnosis and treatment options for clinicians and patients. All available methods for evaluating the prostate including ultrasound, CAT and MRI have false positive and false negative results. MRI is being evaluated for use with a negative ultrasound guided biopsy to determine if it can help improve diagnosis. MRI may be most helpful when evaluating a measurable tumor, and least helpful when the cancer is microscopic.
|Prostate Anatomy||Prostate Anatomy Seen Under MRI|
|Prostate Gland Seen With Ultrasound||MRI images help differentiate between tumor and healthy tissue|
- Prostate MRI is a noninvasive imaging technique that does not require exposure to ionizing radiation.
- Prostate MRI provides more clear and detailed images of the soft-tissue structures of the prostate than other imaging methods. The detail makes MRI an invaluable tool in early diagnosis and evaluation of tumors.
- MRI contrast material is less likely to produce an allergic reaction than the iodine-based materials used for conventional x-rays and CT scanning.
MRI is most accurate when obtained with an endorectal coil. This coil is placed in the rectum at the start of the exam. Similar to ultrasound probe, the coil is placed rectally because it provides the greatest amount of signal when placed near the gland. This increased signal from the endorectal coil helps to provide excellent resolution (image quality).
The endorectal coil, sometimes called a balloon coil, has a flexible shaft with a small balloon on one end. Once inserted, the balloon is filled with either air or a special liquid until it comes into contact with and conforms to the size and shape of the prostate. It is not painful, however, it may cause some initial discomfort.
The total exam time is about 40 minutes. You may be asked to restrict your diet for a short period prior to the exam. Each institution has a patient prep procedure and that will be explained to you at the time of scheduling the examination.