The ultrasound system Exact Vu It is a novel imaging tool created with the intention of assisting the urologist in the diagnosis of prostate cancerIts physical and technical characteristics allow the prostate to be visualized with much greater clarity and precision than conventional ultrasound.
What are the main features of this ultrasound system?
Conventional intracavitary ultrasound systems (including conventional transrectal ultrasound) typically operate at a frequency of 6-9 MHz. The system Exact VU It operates at a frequency of 29 MHz, which allows it to achieve image quality up to 300 times better than the ultrasound conventional.
It also features a significant improvement in axial image resolution (70 µm) compared to conventional transrectal ultrasound (200 µm). This resolution is approximately the diameter of a prostatic duct and allows for the visualization of subtle changes in ductal anatomy (which is where the prostate gland normally originates). prostate cancer).
In short, it allows you to see the anatomy of the prostate in real time, with a level of detail and precision never before achieved, and if the urologist observes any area suspicious of cancer, he can take a biopsy in the same act for subsequent analysis and diagnosis.
How are lesions suspected of being tumors identified?
Exact Vu It has a system for stratifying lesions suspected of being tumors, known as the classification PRIMEwhich has broad international validation. In a system created from the anatomical characteristics of the prostate, the homogeneity or heterogeneity of its tissue (the prostatic parenchyma) and the anatomical relationships of the prostate with its neighboring organs (gallbladder, bladder, rectum and the urinary sphincter).
The system has a grading scale from 1 to 5 (scale PRIME), with the higher grades (3-5) having the greatest correlation with the suspicion of clinically significant cancer and requiring treatment.
What advantages does it offer me if I've already had a prostate MRI?
Nowadays, multiparametric magnetic resonance imaging of the prostate (MRI) It is established as a complementary diagnostic test in patients who present with an elevation of PSA and there is a suspicion of prostate cancer.
MRI provides a wealth of information about prostate anatomy and, in many cases, allows for the identification of areas suspected of being tumorous, which can then be precisely studied with a fusion biopsy. It also uses a grading scale, known as the PIRADS classification, which ranges from 1 to 5. Type 1-2 lesions are considered benign, and type 4-5 lesions are considered highly suspicious for malignancy. Grade 3 lesions are considered indeterminate, and in 15-20 percent of cases, they may indicate the presence of prostate cancer.
However, MRI also has several limitations. It is a relatively expensive technology, requires a significant learning curve for the radiologist, and necessitates a second visit to perform the targeted fusion biopsy. MRI can miss approximately 15 percent of clinically significant cancers. Furthermore, a potential new application of high-resolution ultrasound would be to determine which patients with PIRADS 3 lesions on prostate MRI will require a biopsy and which will not.
It's also important to consider that, from a clinical perspective, providing access to MRI for all patients for whom it is indicated is a challenge, which can result in very long waiting lists. Furthermore, MRI interpretation is complex and subject to variation.
Finally, some men have a relative or absolute contraindication for MRI, such as claustrophobia, prosthetic implants, pacemakers, or renal insufficiency that prevents the use of intravenous contrast.
In short, high-resolution ultrasound offers the advantage of being a relatively simple technology, which, combined with current technologies, allows us to make an accurate diagnosis of prostate cancer.
