How much urine is needed for prostate B-mode ultrasound depends on the capacity of the patient’s bladder. Some people can hold back 100 milliliters of urine, while others need about 300 milliliters, so there is generally no clear value. It’s best to do it when you feel like holding back urine for a while, but not when you urinate immediately.
The reason why we need to hold our urine is to keep the bladder in a normal filling state, so that we can separate the prostate from the bladder for detection, not only to better observe the external structure of the prostate, but also to check the shape, size and nature of the prostate, and to analyze the internal tissue structure of the gland, whether the light spots in the prostate are evenly distributed, and whether the middle lobe of the prostate protrudes into the bladder. So as to find the lesions inside and provide the basis for differential diagnosis.
On the contrary, if the bladder is in a collapsed and empty state, it is difficult to separate the bladder from the prostate, and it is difficult to find local bladder damage.
In addition to easy observation, B-mode ultrasonography of the prostate has the following advantages:
1. It is fast, intuitive and clear, not only harmless to patients, but also can be repeatedly examined, and its cost is much lower than that of CT and magnetic resonance imaging. B-mode ultrasound images of benign prostatic hyperplasia can also reflect the development and changes of the disease, and have a high accuracy in the differential diagnosis of benign prostatic tumors.
2. While measuring the prostate, it can also measure the residual urine volume, which is non-invasive by B-mode ultrasound, avoiding the risk of infection caused by catheterization, and easy to repeat many times.
3. It can also determine whether there will be urinary calculi and whether there is hydronephrosis.
If the above advantages are not worth mentioning before the “pain” of holding your urine, you can also choose transrectal prostate ultrasound examination, that is, the anus as the entrance to the examination, which does not require holding your urine.