OMT ultrasound: how is it done and what is included in the pelvic ultrasound? Norms and pathologies of pelvic ultrasound in women: transcript and protocol Examination of pelvic ultrasound.

Frequently asked Questions

On what day of the cycle do pelvic ultrasound

An ultrasound examination of the pelvic organs is recommended to be carried out in the initial phase of the menstruation cycle - on the 5-7th day from the onset of menstruation. In preparation for in vitro fertilization (IVF), ultrasound can be scheduled for 2-4 days of menstruation.

Do I need to prepare for an ultrasound?

Features of preparation for ultrasound scanning of the pelvic organs depend on the method by which the study is carried out (transabdominal, transvaginal or transrectal diagnostics). To general recommendations preparation includes following a sparing diet and taking enzyme preparations to improve digestion.

What does an ultrasound of the pelvic organs in women show?

In women, a pelvic ultrasound is performed to visualize anatomical features and pathological disorders Bladder, uterine cavity, ureters and other organs of the genitourinary system. During pregnancy, ultrasound allows you to monitor the development of the fetus and assess the condition of the reproductive organs of the future woman in labor.

Where is the best place to do a pelvic ultrasound in women

The Gynecologists.Moscow website contains contacts and addresses medical centers Moscow, where you can do an ultrasound of the pelvis. After reading the reviews of patients, finding out the cost of the procedure and other necessary information, you can sign up for the study. The most popular metro stations in Moscow for the pelvic ultrasound service are:,.

How much does a pelvic ultrasound cost?

The price for an ultrasound examination of the small pelvis in women is formed taking into account several factors: the pricing policy and the location of the chosen medical center, the quality of the equipment used, the qualifications of the specialist, the methodology for the procedure, as well as the goals and objectives of the diagnosis.

How can I book a pelvic ultrasound?

To sign up for an ultrasound of the pelvic organs, first you need to choose a suitable clinic. The questionnaire of each medical center contains the necessary contact information, work schedule and telephone number where you can contact the consultants of the medical institution and sign up for the study.

Ultrasound diagnostics has firmly entered medicine as a study that allows you to find out many important nuances. With the help of this manipulation, the doctor can see the structure, location and functioning of the organs.

Unlike x-rays, ultrasound is a more accurate examination. It, contrary to popular belief, does absolutely no harm. All age groups of the population are diagnosed: children, people of reproductive age, elderly patients. Pregnant and lactating women are no exception. The most common procedure of all ultrasound diagnostics is pelvic ultrasound in women.

• What organs does the specialist examine?

  The study of ultrasound diagnostics in women is carried out in several ways. Depending on the state of health, the abdominal, vaginal or rectal route of delivery of sound waves is selected.

  Less commonly used diagnostics through the perineal region. The most informative examination in non-pregnant women is It is not performed in virgins, during menstruation and with allergies to latex.

  What can be seen during the diagnosis? With the help of a conductor sensor and a special gel that improves contact, sound waves, inaudible to the human ear. They are reflected from the surface of organs and formations, after which they are transferred to the device screen in the appropriate form. A specialist sonologist can see echogenic, hyperechoic, and other outlines. Based on the results obtained, a protocol is issued.

  Ultrasound diagnosis of the small pelvis includes examination of the rectum and part of the large intestine, examination of the bladder, ureter, but most often there is a need to study the condition of the reproductive organs. These include the uterus with the cervical canal and neck,. Here is what the ultrasound of the pelvic organs in women shows.

  During the examination, the condition of the female genital organs, such as the uterus, ovaries, fallopian tube, etc., is examined.

  Norms at the beginning of the cycle

  Basically, ultrasound scanning is performed immediately after the end of menstruation. Doctors choose a period from 3 to 7 days of the cycle. Depending on the intensity of bleeding and its duration is set. What can be seen during it?

  If you want to know if there are pathologies and malfunctions in the reproductive function, then you should do an ultrasound after menstruation. the following indicators:

  • the height of the reproductive organ is about 5 cm, and the width is 5, the thickness varies from 3 to 4 cm; after the onset of menopause (after about 10 years), the height and width are reduced by 1 cm, and the thickness remains the same or decreases slightly;
  • the genital organ is defined by smooth and clear contours, and its echogenicity is usually homogeneous;
  • the state of the internal cavity can change every day (in women with a long cycle, the endometrium is not yet visualized, while with a period of 21 days or less, it is already noticeable), additional inclusions and neoplasms are not detected;
  • the size of the appendages (ovaries) is 3/2/2.5 cm (normally one organ may be slightly larger than the other);
  • the cervical canal is tightly closed, the neck without features and additional inclusions.

  Ultrasound can be considered ideal, in the conclusion of which it is indicated “normal” or “no deviations”. But this is not always the case. If you are sent for research at the beginning of the cycle, then they expect to see some kind of pathology. Exactly this best time for the diagnosis of diseases such as ovarian cysts, uterine polyps. What can be seen if they are available?

  Cyst

  This neoplasm differs from the flesh of the appendage in echogenicity. In the conclusion of a specialist, it is usually indicated "in the left (more often right) ovary."

  You should not panic if you saw one during your research. Cysts are different. It will not be possible to reliably establish the nature of the neoplasm during the study. With good equipment, it can be assumed which cyst is functional or non-functional. Further tactics are chosen taking into account this fact.

  

  Cyst is the most common disease among women of childbearing age. This disease does not have pronounced symptoms, however, it is easily detected during regular examinations by a gynecologist.

  Myomas, polyps

  These formations are easy to see at the beginning of the menstrual cycle, when the mucous membrane has separated, and the genital organ has become “naked” from the inside. Pathologies are determined by the thickening of the layers of the uterus, which causes its uneven contour and change in position.

  And fibroids are often due to hormonal imbalance, but may have other causes of origin. Methods of treatment are established depending on the indicators, the size of the neoplasm and the well-being of the woman.

  What can be seen on an ultrasound before ovulation?

  An ultrasound examination, which is scheduled for the period from 7 to 17 days of the cycle, provides for the determination of ovarian pathologies. During this period, their active work begins: which are larger or smaller.

  The largest are called "dominant". They will be the suppliers of eggs in this cycle. It is quite difficult to establish the normal size of the ovaries for this period, since the values ​​\u200b\u200bare changing every day.

  It is important to know what pathologies can be established by a specialist during this period:

  • polycystic (characterized by a large number of follicles in the ovary and the small size of the uterus);
  • anovulatory cycle (no dominant follicles, the mucous membrane of the genital organ does not correspond to the day of the cycle);
  • follicular cyst (an overgrown follicle that can no longer perform its function, as a result of which it will reverse development).

  In the middle of the cycle, pathologies of hormonal origin are predominantly established.

  Shortly before menstruation: what will the examination show and who needs it?

  What can show the diagnosis, which is made after ovulation? This period is the least often chosen for examination. More often, ultrasound before menstruation is necessary for women with pregnancy or those who are planning to conceive.

  Normally, the second part of the cycle is characterized by an increase in the size of the uterus and a thickening of its inner layer - the endometrium. One of the ovaries also acquires a larger volume (due to the formation of corpus luteum).

  Pathologies that a sonologist will detect may be as follows:

  • luteal cyst (excessively large corpus luteum);
  • endometrioma (a cyst that takes on a large size just before menstruation);
  • hyperplasia of the endometrium (its excessive growth in the cavity of the reproductive organ);
  • endometriosis (foci of the endometrium in places that are not characteristic of it).

  Before menstruation, a specialist may or may suggest it. But this is possible only with the help of modern equipment. Old ultrasound diagnostic devices will show the presence of a fetal egg in the uterus only after a delay.

  Deviation signs

  The interpretation of the data obtained should be carried out by an experienced gynecologist. On your own, you will not be able to give a sound assessment of the detected situation, compare some indicators with others and make a diagnosis. But some clue words may make you think about the presence of some kind of pathology.

  So what can be seen during the study?

  Inflammation of the uterus and its appendages

  This condition is characterized by an increase in the size of the organs and their inconsistency with the existing day of the female cycle.

  At inflammatory process appears Sometimes the hormonal background is also disturbed, which is characterized by improper functioning of the ovaries (absence of follicles in them, the appearance of cysts, and so on). The visualized fallopian tubes can speak of the inflammatory process.

  Neoplasms

  You already know how and when cysts, fibroids and polyps are found. These pathologies are clearly visible throughout the cycle (with the exception of menstrual bleeding). They are indicated by unusual inclusions located in different places, which may differ in their echogenicity from the general background.

  

  Signs of fibroids in the picture: increased size of the main female organ, the occurrence in the uterine cavity of a rounded clot. If the image shows that the uterus has changed its shape, it means that the myoma nodes have reached a large size

  adhesive process

  During the diagnosis, it is often assumed in women Causes - inflammatory diseases and surgical interventions. The presence of adhesions can be suspected due to the displacement of organs from their usual places, deformation of the body of the uterus, the appearance of fluid in the retrouterine pocket.

  

  The main complications that appear due to this disease include: intestinal obstruction, chronic pelvic pain syndrome, impaired gestation, infertility

  Ectopic pregnancy

  Easily determined by ultrasound. In most cases, the embryo is found inside the fallopian tubes, which gives them a clear visualization, as in inflammation.

  

  This examination allows you to determine the tubal pregnancy at those stages when the disease does not threaten with dangerous consequences. Such a pregnancy is characterized by the location of the fetal egg in the fallopian tube.

  Less commonly, a fertilized egg can be seen on the outer wall of the uterus, in the ovary, cervical canal, or abdominal cavity.

  Congenital and acquired anomalies

  During ultrasound, such deviations as the bending of the genital organ or its omission, a bicornuate uterus, and oncological diseases are reliably established.

  Conclusion with decoding

  After the diagnosis, the sonologist issues a conclusion to his patient. It prescribes the features seen, indicates the size of the pelvic organs, and gives preliminary conclusions.

  You should not take the information received as a diagnosis, since women do not always interpret it correctly.

  For example, a specialist has discovered that you are pregnant, which is recorded as "hyperechoic formation in the uterine cavity." A woman can interpret this conclusion in the most unexpected way: fibroids, cysts, malignant tumor and so on.

  Therefore, it is so important to contact a gynecologist who will collect an anamnesis, listen to complaints and, based on the results obtained, make a correct diagnosis. With the help of ultrasound diagnostics, many pathologies can be identified or refuted.

  This study allows you to detect pregnancy in the early stages, to examine the cavity of the organ after the installation of the intrauterine device. Ultrasound of the pelvis in women is performed in combination with other manipulations, for example, with metrosalpingography (). It is used for puncture, hysteroscopy. Modern gynecology is simply impossible to imagine without this examination.

The main feature of ultrasound is that it does not use harmful ionizing radiation, as is the case with x-rays. In addition, ultrasound does not show a static picture, but an image, so to speak, online. This allows specialists to assess the movement of organs and blood flow in the vessels.

Indications for pelvic ultrasound

So, the doctor may prescribe a pelvic ultrasound in one of the following cases:

With the help of ultrasound, you can determine pregnancy literally in the first days after conception.

The doctor prescribes ultrasound for women with any failures and irregularities of the menstrual cycle, whether it is a delay in the onset of menstruation or too early menstruation, bleeding in the middle of the cycle, and so on. Ultrasound is also prescribed for excessively strong or weak menstruation, with incomprehensible vaginal discharge, with discharge after menopause, and, of course, if menstruation is completely absent.

Ultrasound of the uterus is prescribed for suspected difficult-to-treat disease - uterine myoma.

Ultrasound also allows you to identify all the formations on the uterus and ovary (both malignant and benign).

Various inflammations of the pelvic organs are also indications for ultrasound diagnostics.

The gynecologist may prescribe a study to monitor the intrauterine contraceptive (spiral), as well as in case of complaints about side effects from such a contraceptive.

Pelvic ultrasound is performed for both sexes in the presence of any problems with the genitourinary system.

Obstetricians prescribe ultrasound for early detection all pathological disorders of the fetus, checking the condition and tone of the uterus during pregnancy and simply to control its development of the child.

Also, ultrasound is a mandatory procedure when searching for the cause of infertility in men and women.

Ultrasound is always prescribed for possible obstruction of the fallopian tubes in women.

It is important to note that ultrasound is prescribed for men, in case of suspicion of any pathology of the prostate gland (prostate) and seminal vesicles.

Children are also sometimes prescribed pelvic ultrasound for severe pain in the pelvic area.

What can a pelvic ultrasound reveal?

In addition to monitoring pregnancy and the process of fetal development, pelvic ultrasound in women can find a number of serious illnesses. First of all, of course, these are neoplasms, such as cysts, polyps and fibroids. Ultrasound can also show whether a woman has ovarian or uterine cancer. Ultrasound is able to detect almost all anomalies of the uterus, including scars on the uterus.

In both men and women, ultrasound of the pelvic organs reveals diseases of the bladder, including a tumor (cancer) of the bladder, as well as the presence of stones and sand in the kidneys. As for children, their ultrasound reveals various neoplasms and anomalies in the pelvic area, heterogeneity of the genital organs. At little girls Ultrasound can show too early or too late puberty.

special kind Ultrasound - Doppler ultrasound, shows such nuances as congenital vascular malformation, blockages and blood clots in the bloodstream, narrowing in the vessels, the appearance of blockages in the vessels.

Preventive ultrasound of the pelvic organs

Ultrasound is not always sent only in the presence of any diseases. The purpose of ultrasound is early diagnosis of the disease, because at the most early stages any disease is much more treatable. So it is very necessary to undergo ultrasound for prevention purposes, this is especially important for women.

How often should this be done? Healthy young women need to undergo such an ultrasound for prevention purposes at least once every two years. Women after forty need to do such an ultrasound more often - once a year.

For the most reliable result, it is important to undergo preventive ultrasound at the beginning of the menstrual cycle - on the fifth to seventh day after the onset of menstruation.

Ultrasound (ultrasound) of the pelvic organs is a reliable method for diagnosing diseases of the reproductive and urinary systems. This study helps to clarify the diagnosis and identify pathology at an early stage of development. It should be remembered that the reliability of the result will depend on the correct preparation for the study.

When is an Ultrasound Ordered?

Ultrasound is safe method diagnosis, which has no contraindications. It can be passed to the fair sex at any age.

Indications for pelvic ultrasound are:

What does an ultrasound of the pelvic organs in women show?

An ultrasound examination of the pelvic organs is performed to detect pregnancy.

Pelvic ultrasound can detect pregnancy early term. For more later dates Ultrasound allows you to assess the correct development of the fetus and the condition of the uterus.

Also, with the help of this examination, it is possible to identify the presence of congenital malformations in the fetus, anomalies incompatible with life, and also determine the sex of the child.

When conducting a survey in women, the pelvic organs are evaluated according to the following criteria:

• The correct location of the internal genital and urinary organs, their relationship to each other (uterus, appendages, bladder);
• Determination of the external and internal dimensions of the uterus;
• The contours of the uterus and bladder, the structure of the inner layer;
• The state of the myometrium (the muscular membrane of the uterus);
• The state of the endometrium(mucous membrane of the uterus);
• Dimensions of the appendages (ovaries and fallopian tubes);
• The structure of the appendages, identifying the presence of adhesions, follicles and cystic formations;
• Size of the cervix. This indicator is very important in the second half of pregnancy. If it is shortened, then the woman is diagnosed with a "threat of abortion";
• The correct position and structure of the cervix;
• The condition of the bladder, determining the presence of stones (stones and sand) in the cavity of the organ.

Ultrasound helps to assess the condition of the surrounding soft tissues and regional (nearby) lymph nodes.

How is a pelvic ultrasound done?

Ultrasound examination of organs reproductive system and bladder is carried out in a specially equipped room. This will require an apparatus consisting of a screen on which an image is displayed and a special sensor.

The patient should release the examination area from clothing and lie on the couch in the supine position. The legs must be bent at the knees. This will help relax the abdominal muscles.

Ultrasound of the pelvis in women is done in 3 ways:

Study preparation

Preparation for this examination depends on the method by which the ultrasound will be performed.

You will be interested in:

Transvaginal examination does not require special preparation. Several conditions must be met:

• Visit the shower before the study;
• Empty the bowels on the day of the study;
• The bladder must be empty, so it is worth visiting the toilet room before the examination.

Features of preparation for transabdominal and transrectal examination:

When is the best time to do a pelvic ultrasound?

The time for the examination is selected depending on the purpose of the diagnosis. If screening is carried out for pregnant women, then the timing depends on the gestational age:

• The first screening examination should be carried out from 10 to 14 weeks;
• The second examination - from 22 to 24 weeks;
• The third examination - from 32 to 34 weeks.

If ultrasound of the small pelvis is carried out for a preventive purpose, then it is recommended to do it immediately after menstruation on the 5th - 8th day of the cycle.

If tumors and cysts are suspected, an ultrasound can be done on the 5-7th day of the cycle, and with endometriosis, the examination is carried out in the second half of the cycle.

To assess the functionality of the ovaries is carried out three times in one menstrual cycle:

• From 8 to 10 days of the cycle;
• From 14 to 16 days of the cycle;
• From 22 to 24 days of the cycle.

Deciphering the results of the study

The doctor of ultrasound diagnostics is engaged in deciphering the results of ultrasound of the pelvic organs. A gynecologist interprets the results and, on their basis, a diagnosis is made.

Ultrasound of the uterus is done when diagnosing diseases and during pregnancy. When examining the uterus, its parameters are evaluated.

Normal ultrasound of the uterus is:

• The length of the uterus is about 70 millimeters;
• Width - about 60 millimeters;
• Anterior-posterior size - about 40 millimeters;
• The thickness of the endometrium corresponds to the day of the menstrual cycle.

If an intrauterine device is installed in the uterus, then its location is evaluated. Normally, it should be securely fixed in place.

When determining a short term pregnancy, it is found amniotic sac in the uterine cavity.

When examining the ovaries, the size, structure and presence of follicles and cystic formations are recorded.

In the nome, the ovarian parameters are as follows:

• Length about 30 millimeters;
• Width about 25 millimeters;
• The thickness is about 15 millimeters.

It should be noted that the presence of follicular cysts in women of childbearing age is considered a variant of the norm.

Normally, the fallopian tubes are not visualized on ultrasound because they are hollow.

Any deviation from the above norms is a sign of the presence of a pathology of the organs of the woman's reproductive system.

Normal bladder examination:

• The dimensions and shape of the hollow organ are not changed;
• Stones, sand and tumor formations were not found;
• The ureters are passable, through them urine freely and evenly penetrates into the bladder;
• After emptying the bladder, no residual urine is observed in it.

Men are tested if they have the following symptoms:

• erectile dysfunction;
• atypical discharge from the urethra;
• pain in the lower abdomen, in the lower back;
• blood in ejaculate or urine;
• violations of the process of urination (change in the frequency of urination and the amount of urine, pain).

For women, the following signs indicate the need to pass:

• atypical bleeding;
• pain in the lower abdomen;
• disruption of the menstrual cycle.

Ultrasound methods

Surveys can be carried out in three ways:

• transabdominal - through the wall of the abdominal cavity;
• transvaginal - through the vagina;
• transrectal - through the rectum.

If necessary, the methods can be combined.

Transrectal and transvaginal ultrasound provide more information than transabdominal. However, the first two methods have contraindications. Some patients are shown only transabdominal ultrasound.

Contraindications

In itself, ultrasound has no contraindications. Ultrasound does not harm children, pregnant women, or elderly patients. However, the research method must be taken into account.

There are no contraindications for transabdominal ultrasound, except that the patient's obesity makes the examination difficult. Fat layer greatly reduces image clarity.

Transvaginal ultrasound of the pelvic organs is not done in the second and third trimester of pregnancy. In the first trimester, a transvaginal examination can be performed.

Transrectal examinations are contraindicated:

• with intestinal obstruction;
• after surgical operations on the rectum;
• with hemorrhoids;
• in the presence of chronic sphincter fissures.

Virgins do either transrectal or transabdominal ultrasound.

Ultrasound is not recommended after X-ray examination with contrast. The contrast agent may interfere with the reliability of the results. It is better to go for an x-ray after an ultrasound.

Also, ultrasound examination of the pelvic organs may be uninformative after colonoscopy and gastroscopy. These procedures increase gas formation in the intestines.

Training

Preparation for the study depends on the type of procedure. However, there are general measures: before all types of ultrasound, it is necessary to clear the intestines from gases. To do this, 3 days before the examination, you need to abandon gas-forming products:

• flour;
• sweet;
• raw vegetables and fruits;
• legumes;
• dishes with cabbage;
• whole milk and dairy products;
• carbonated, caffeinated and alcoholic drinks.

You can eat boiled lean meat (turkey, chicken, beef), cereals, hard-boiled eggs (one per day).

Also in these 3 days, with increased gas formation, enterosorbents are welcome. However, do not "assign" them to yourself arbitrarily. Let the doctor determine the need for such a measure.

Features of preparation for different types procedures:

• Transabdominal ultrasound is performed with a full bladder. An hour before the procedure, drink 1-1.5 liters of pure non-carbonated water and do not empty the bladder.
• On the eve of transrectal ultrasound, the intestines are emptied using an enema or glycerin suppositories. Cleansing actions are repeated in the morning, before the examination.

Diagnosis of pathologies using ultrasound

For women, the procedure is carried out in order to identify:

• inflammation;
• dysfunction of the organs of the reproductive system;
• neoplasms;
• diseases of the ovaries and uterus.

Men are examined for the purpose of diagnosing diseases of the prostate gland.

Ultrasound is used for both women and men in the diagnosis of:

• tumors;
• diseases of the bladder and urinary tract;
• other pathologies internal organs.

When is the best time to do a pelvic ultrasound?

For men, the study can be performed at any time period according to the indications.

But the question is, when is it better to do an ultrasound of the pelvic organs in women - not idle, since the phase of the cycle significantly affects many indicators, for example, the thickness of the endometrium.

On what day of the cycle is it better to do an ultrasound of the pelvic organs depends on the diagnostic task.

Most often, scanning is carried out for a period up to the 10th day of the cycle. However, there are other schemes for its purpose.

When diagnosing the causes of infertility, three ultrasound examinations are prescribed in different phases monthly cycle:

1. From 8 to 10 days. The choice of the optimal and dominant follicle is made.
2. From 14 to 16 days. Its volume is measured.
3. From 22 to 24 days. The presence of a corpus luteum and the presence or absence of ovulation are determined.

Before IVF planning, the procedure is performed on the first 2 days of the cycle to determine the number of follicles, regardless of the abundance of menstruation.

In menopausal women, the study is performed at any time.

Deciphering the results of the study

The conclusion of the ultrasound is performed according to the following characteristics of the organ under study: size, volume, uniformity of its structure, echogenicity, clarity of contours. There are many parameters for evaluating the results of ultrasound of the pelvic organs, here are some of them.

Uterus.The shape is pear-shaped or oval. Average echogenicity of the myometrium. The endometrium with well-defined contours, of uniform thickness, with high echogenicity, is located in the center of the uterus. Normative indicators of the size of the organ depend on such factors - the day of the monthly cycle, the number of pregnancies and childbirth in history, the age factor (menopause).

Standards for the size of the uterus

Separately measured the size of the cervix and its ratio to the body of the uterus.

Ovaries. Their size varies greatly depending on the day of the monthly cycle, the age of the woman, the use hormonal drugs, including contraceptives.

Shape, length, width and thickness are measured. For the ovaries, the volume and number of follicles is determined.

Norms of the size of the ovaries

What does a pelvic ultrasound show in women?

We list some examples of pathological changes:

• The pathological increase in the size of the uterus, together with the presence of rounded areas with heterogeneous echogenicity, is in favor of fibroids.
• Sarcoma is similar to myoma, but the neoplasms have reduced echogenicity and internal cystic inclusions.
• Uneven wall thickness, increased size of the uterus, increased echogenicity of the myometrium indicates endometriosis.
• A decrease in the uterus with a simultaneous increase in the ovaries may indicate their polycystic ovaries (PCOS).
• The inflammatory process in the ovaries - oophoritis, can be diagnosed with a decrease in echogenicity and a spherical shape of the organs.

Some diagnoses should be clarified with the help of additional studies. For example, the diagnosis of "uterine sarcoma" can only be made based on the result of a histological examination.

With the help of ultrasound, indirect signs of erosive processes of the cervix can be detected, but colposcopy is necessary to confirm the diagnosis. Also, this study will be needed to diagnose dysplasia and cervical cancer - ultrasound does not detect them.

How is a pelvic ultrasound performed?

All types of ultrasound of the pelvic organs are carried out in approximately the same way:

1. The patient lies on his back (during transrectal examination - on his side).
2. In a transabdominal ultrasound, a gel is applied to the areas to be examined, then a probe is passed over the body. For transvaginal and transrectal examinations, a transducer placed in a condom is treated with a gel and then inserted into the vagina or rectum.

Ultrasonic waves, reflected from the examined tissues, make it possible to study the image of organs on the monitor in real time. This is very important if it is necessary to assess the movements of internal organs and the characteristics of blood circulation.