Ultrasound signs of prostate and seminal vesicle disease

Ultrasound evaluation of diseases of the prostate gland and seminal vesicles

In acute prostatitis, both increased and decreased vascularization may be observed equally depending on the stage of the inflammatory process. When the hyperemia phase prevails, increased vascularization and decreased IR in the vessels of the gland are observed, whereas in the edema phase, decreased vascularization and increased IR prevail. The importance of transrectal ultrasound with new technologies in monitoring the treatment of patients with prostatitis has been clearly demonstrated in a number of studies. In acute prostatitis, it is recommended to monitor the treatment after 2-3 days using a comprehensive study of the vessels to determine the effectiveness of the therapy. The dynamics of vascularization changes is an indicator of the treatment effect. With a positive effect, there is restoration of the symmetry of the vascular pattern, enrichment of the vascular pattern and increased perfusion of the gland (in areas with previously reduced blood flow) or a decrease in the degree of vascularization in areas with previously increased blood flow. When analyzing changes in venous blood flow, a reliable increase in the linear velocity of venous blood flow in the periprostatic venous plexus is observed by an average of 5.3 ± 2.1 cm / s (15%), indicating an improvement in venous outflow and, as a consequence, a decrease in congestion. Similar changes are noted in the intraprostatic veins (periurethral and capsular).

The ultrasound angiography technique allows suspecting the formation of a prostate abscess at early stages and identifying the ineffectiveness of the treatment. In the gray scale mode, even when using the tissue harmonic mode, it is impossible to immediately suspect the formation of an abscess. With ultrasound angiography, this zone is usually avascular or hypovascular. A decrease in the degree of vascularization of the gland or a decrease in vascularization in the focal focus during a control study also indicates a deterioration in the blood supply to the inflammation zone and subsequently, in the absence of treatment adjustments, leads to the formation of an abscess. With ultrasound angiography, an abscess is characterized by a "flaming ring" blood flow.

Vesiculitis is determined echographically by a sharp expansion of the seminal vesicles with thickened walls filled with anechoic contents. With ultrasound angiography, increased blood flow is localized in the walls of the seminal vesicles.

In chronic prostatitis, the analysis of vascularization using ultrasound angiography techniques in all patients with predominantly fibrous changes showed a local decrease in vascularization in fibrosis zones. In some cases, with long-term chronic prostatitis, a general decrease in vascularization of the gland was noted. The peak LSC and IR values in the intraprostatic arteries in patients with chronic prostatitis were practically no different from similar values in the normal group.

In benign prostatic hyperplasia, the vascular pattern changes significantly, mainly due to hyperplasia of the urethral group of arteries, which has been described in a number of scientific papers. It is characterized by a hyperplastic type of vascularization. The ratio of the degree of vascularization of the central and peripheral parts of the gland is disrupted due to a decrease in vascularization of the peripheral zone and an increase in vascularization of the central part.

Benign hyperplasia

The prostate gland is accompanied by not only qualitative but also quantitative changes in hemodynamics. It is characterized by an increase in peak blood flow velocities on average to 14.8 ± 5.2 cm / s in the urethral arteries and to 16.8 + 4.3 cm / s in the capsular arteries, IR to 0.71 ± 0.08 and 0.72 + 0.09, respectively, regardless of the form of adenoma growth.

Prostate cancer, according to many researchers, is characterized by hypervascularization in the affected area. However, it has been established that hypervascularization is not a decisive factor in its diagnosis. In prostate cancer, both hypervascular and hypovascular tumors are equally common. The degree of tumor vascularization is closely related to its ability to grow quickly and metastasize. Studying the angioarchitectonics and nature of the vascular pattern is more important than determining the degree of tumor vascularization. Tumor vessels differ from normal ones. Tumor vessels are characterized by pathological branching, different calibers, tortuous course, blind pockets instead of terminal arterioles. This type of vascular pattern is called "disorganized". Determining the nature of the vascular pattern is possible most fully using the technique of three-dimensional angiography. Three-dimensional reconstruction of vessels allows more accurate assessment of the vascular pattern of the gland as a whole, identifying not only areas of vascular pattern asymmetry, but also identifying neovascularization zones, and talking about the spatial distribution of vessels in the tumor. In this mode, it is possible to more accurately perform differential diagnostics of various hypoechoic areas in the prostate gland. This allows already at the first stage to distinguish hypoechoic areas in acute prostatitis and cancer in elderly patients. The study of vascularization symmetry increases the positive predictive value of TRUS in identifying infiltrating isoechoic tumors and tumors with fuzzy contours. In the absence of local changes in the gray scale mode, vascular pattern asymmetry, local decrease or increase in the degree of vascularization can provide some assistance in searching for isoechoic tumors and infiltrating prostate cancer.

Prostate adenoma on scanograms is a homogeneous formation, different in shape and size, but always with clear, even contours and a well-defined capsule. Adenomatous tissue of the gland can develop unevenly and look asymmetrical during frontal echoscanning. With the predominance of glandular elements, stromal edema due to adenoma and the accompanying inflammatory process, the echogenicity of the gland can be diffusely reduced: small anechoic rounded formations are sometimes found in the parenchyma. In the case of chronic inflammation, hyperechoic inclusions (sometimes with an acoustic path) appear in the parenchyma, located, as a rule, in the transitory zone and along the surgical capsule or on the border of the central and peripheral zones.

To establish the causes of lower urinary tract obstruction and assess structural changes in the urethra, micturition ultrasound cystourethroscopy (echourodynamic study) is used. The essence of the method is TRUS of the prostate, performed during urination. The passage of urine through the urethra allows the latter to be seen during echography, which is impossible when it is in a subsided state. On transrectal echograms at the time of urination, the neck of the bladder is determined as a funnel with a clear and even internal contour, the prostatic and? Partially, membranous sections of the urethra, about 5 mm thick. If the cause of obstruction is prostate adenoma, then the urethra in this place is visualized as a thin anechoic strip less than 5 mm wide. Deviation of the urethra by adenomatous tissue depends on the form of its growth. Micturition ultrasound cystourethroscopy is of great importance in recognizing urethral strictures, especially if the patient has prostate adenoma. It allows determining the condition of the urethra proximal to the site of stenosis, localization and, in some cases, the length of the stricture. During urination, if its violation is not associated with prostate adenoma, with stricture, dilation of the urethra is noted above the stenosis (including the prostatic section). With inflammatory stenosis, the outlines of the urethra are clear, rectilinear, the diameter of the healthy part of the urethra is not changed.

In addition to diagnosing structural changes in the urethra, micturition ultrasound cystourethroscopy in combination with UFM or Doppler ultrasonography of the urine flow allows detecting functional changes in the urethra and bladder.

IVO in prostate adenoma leads to structural and functional changes in the urinary tract (e.g., bladder). Determining the volume of residual urine using ultrasound is an important method for diagnosing and staging prostate adenoma.

Prostate cancer is characterized by echographic features in the form of the formation of heterogeneous hypoechoic nodes in the peripheral zone.

Depending on the stage, symmetry disturbances, uneven contours and thinning of the capsule are observed. In 13% of cases, ultrasound shows that cancerous nodes have a more pronounced echogenicity than the gland tissue, and in 9% they are isoechoic or not detectable at all.

Echographic changes in prostatitis depend on the form of inflammation and are extremely diverse. Thus, in acute prostatitis, an increase in the size of the gland and a decrease in its echo density are noted both in individual areas and in the entire gland. An abscess of the organ is quite easily diagnosed using TRUS. The echographic picture has characteristic features. An abscess looks like a formation of a round or irregular shape with significantly reduced echogenicity, almost approaching that of a liquid structure (anechoic in nature). The structure of the prostate abscess is heterogeneous due to the content of purulent-necrotic masses in it; anechoic (liquid) inclusions are often observed. With color Doppler mapping, there is no blood circulation in the abscess area, and a clearly defined vascular network is found around it.

In chronic inflammatory process in the prostate outside of exacerbation, changes in the structure of the organ associated with sclerotic changes come to the fore, which in echography look like hyperechoic areas without an acoustic effect. Stones in the prostate look like hyperechoic, often multiple formations with a clear acoustic path. Echo-Dopplerography of the prostate allows to study the features of blood circulation in it in various diseases, which increases the diagnostic value of the method.