CT scans of the pelvis are carried out to detect existing pathologies in the early stages. We are talking about the most informative scanning technique. I use it to examine hard and soft tissues. It allows you to determine the state of:
- bones;
- vessels;
- The lymph nodes;
- organs and tissues of the pelvic area.
Computed tomography of the pelvic organs is painless, patients do not feel discomfort during such an examination.
CT scan of the pelvic organs in a good clinic
In our clinic, CT scans of the pelvis can be performed in comfortable conditions. The center’s doctors are highly qualified and know how to properly carry out this procedure. After the examination, patients are given a conclusion and can receive advice from an experienced specialist. The clinic has modern equipment for high-quality pelvic diagnostics. Doctors use effective methods for identifying pathologies at the stage of their inception.
Modern equipment for examining the pelvis allows you to perform up to 128 sections. The accuracy of diagnosis depends on the number of sections; the more, the better. Scanning an area of 5 cm takes approximately 5 seconds. The accuracy of the results is beyond doubt.
There are tomographs that allow you to examine organs in the pelvis in women and men not only with normal weight, but also with excess weight. In some cases, the procedure is performed with contrast. The use of a contrast agent, usually iodine, improves the quality of the resulting images. This greatly simplifies making the correct diagnosis.
Many people are interested in what a pelvic CT scan shows in male and female patients. With the help of such diagnostics, various pathologies are identified.
Pelvic bones
The pelvic girdle, or pelvis, is a strong bony ring that is located in the lower part of the human torso skeleton. It is formed from almost motionlessly connected bones: the unpaired one - the sacrum and two massive, flat ones - the right and left pelvic bones. Wedged between the pelvic bones is the sacrum, to which is attached a small bone - the coccyx - a rudimentary remnant of the caudal skeleton.
In children under 16 years of age, each pelvic bone consists of 3 separate bones: the ilium, the ischium and the pubis, connected to each other by layers of cartilaginous tissue. After 16 years they grow together. At this place there is a deep fossa - the acetabulum. The head of the femur enters it, forming the hip joint.
The structure of the ischium The ischium has a powerful ischial tuberosity, on which the human body rests when sitting. If a person stands, the ischial tuberosity is hidden by a thick layer of gluteal muscles and fatty tissue.
The structure of the pubic bone The pubic bone has 2 branches connected to each other at an angle. These branches, together with the branch of the ischium, limit the large obturator foramen on the pelvic bone, covered with a dense membrane. The pubic bones on the right and left are connected to each other through cartilage - thus forming the pubic symphysis (half-joint), one of the joints of the pelvic girdle. The elevation of the skin above the symphysis is called the pubis.
The significance of the pubic symphysis is especially great for the female body. By the time of childbirth, the cartilaginous layer between the pubic bones softens, and the gap inside it allows the bones to move apart and thereby slightly expand the birth canal.
The structure of the ilium The ilium consists of a body and a thin wing, which expands upward and ends in a long crest. The ridge serves as the attachment point for the broad abdominal muscles. The depression on the inner surface of the wing forms the iliac fossa. It is in this fossa on the right that the cecum with the vermiform appendix (appendix) is located.
At the back of the ilium there is an articular surface shaped like the auricle. It is tightly connected to exactly the same surface on the sacrum, forming a flat sacroiliac joint. This joint is strengthened on all sides by bundles of ligaments, which in terms of their strength are considered the most powerful in the human body.
Angle of inclination of the pelvic bones The pelvic bones are the attachment point for the muscles of the abdomen, back and lower extremities. In a vertical position of a person, the pelvis is tilted forward at an angle of 45–60 degrees relative to the horizontal plane. The size of the angle depends on posture; in women it is larger than in men.
Examination with a tomograph with reduced radiation dose
CT scan of the pelvic vessels is highly informative. Modern tomographs can operate in several modes. They make it possible to perform scanning with a small radiation dose, without compromising the quality of the resulting images.
The patient receives the results of the examination in his hands. They are captured on the disk. The clinic’s doctors have extensive experience in deciphering the data obtained during the examination of tomographs. Typically, preparing a report takes no more than an hour.
Why is a pelvic CT scan prescribed?
Diseases of organs located in the pelvis are common. The earlier the pathology is detected, the greater the chances of successful treatment. To diagnose disorders they perform. This procedure can be prescribed to patients of both sexes.
It is carried out in order to detect:
- benign and malignant tumors;
- injuries and violations of bone integrity;
- ruptures of internal organs;
- negative transformations in veins and vessels.
This examination is prescribed if there is a suspicion of prolapse or prolapse of the bladder. It makes it possible to detect sand with stones in the bladder and ureters.
For women, CT scans are prescribed to identify inflammatory pathologies, prolapse or prolapse of the uterus. It allows you to find out if there is an accumulation of blood with pus in the lumen of the fallopian tube.
In men, tomography can reveal:
- prostatitis;
- prostate adenoma;
- inflammatory processes in the seminal vesicles;
- disorders in the development of the genitourinary system;
- inflammation of the testicles.
While studying the images, the doctor assesses the condition of the tailbone and other tissues. This method of examination makes it possible to differentiate pathologies, since diagnosis in many cases is complicated by similar symptoms.
Due to a detailed examination, the diagnosis is greatly simplified.
Text of the book "Obstetrics"
STRUCTURE OF THE FEMALE PELVIS
By puberty, a healthy woman’s pelvis should have a normal shape and size for a woman (Fig. 11).
To form a correct pelvis, the girl’s normal development during the prenatal period, prevention of rickets, good physical development and nutrition, natural ultraviolet radiation, injury prevention, normal hormonal and metabolic processes are necessary. Pelvis
(
pelvis
) consists of two pelvic, or nameless, bones, the sacrum (
os sacrum
) and the coccyx (
os coccygis
).
Each pelvic bone consists of three fused bones: the ilium ( os ilium
), ischium (
os ischii
) and pubis (
os pubis
).
The pelvic bones are connected in front by the symphysis. This inactive joint is a semi-joint in which the two pubic bones are connected by cartilage. The sacroiliac joints (almost immobile) connect the lateral surfaces of the sacrum and the ilia. The sacrococcygeal joint is a movable joint in women. The protruding part of the sacrum is called the promontory ( promontorium
).
In the pelvis there is a distinction between the large and small pelvis. The large and small pelvis are separated by the innominate line.
The differences between the female pelvis and the male pelvis are as follows: in women, the wings of the ilium are more deployed, the small pelvis is more voluminous, which in women has the shape of a cylinder, and in men it has the shape of a cone. The height of the female pelvis is smaller, the bones are thinner.
Measuring the size of the pelvis.
To assess pelvic capacity, 3 external dimensions of the pelvis and the distance between the femurs are measured.
Measuring the pelvis is called pelvimetry
and is carried out using a pelvimeter.
Rice. eleven.
Structure and planes of the pelvis:
A
– plane of entrance to the pelvis;
b
– plane of exit from the small pelvis;
1
– straight size;
2
– transverse size;
3
– left oblique size;
4
– right oblique size
Rice. 12.
Pelvimetry:
A
– technique of external measurement of the pelvis using Martin’s compasses:
1
– the distance between the anterosuperior iliac spines (
d. spinarum
);
2
– distance between the crests of the iliac bones (
d. cristarum
);
3
– distance between greater trochanters (
d. trochanterica
)
External dimensions of the pelvis
:
1. Distancia spinarum
- interspinous distance - the distance between the anterosuperior spines of the iliac bones (spine -
spina
), in a normal pelvis is 25 - 26 cm.
2. Distancia cristarum
– intercrestal distance – the distance between the most distant points of the iliac crests (crest -
crista
) is normally 28 - 29 cm.
Rice. 12
(
continuation
):
b
– measurement of the external conjugate (
conjugata externa
)
3. Distancia trochanterica
– intertubercular distance – the distance between the greater tuberosities of the trochanters of the femurs (greater tuberosity -
trochanter major
), normally equals 31 cm.
4. Conjugata externa
– external conjugate – the distance between the middle of the upper edge of the symphysis and the suprasacral fossa (the depression between the spinous process of the V lumbar and I sacral vertebrae). Normally it is 20 – 21 cm.
When measuring the first three parameters, the woman lies in a horizontal position on her back with her legs extended, and the pelvic meter buttons are placed on the edges of the size. When measuring the direct size of the wide part of the pelvic cavity, to better identify the greater trochanters, the woman is asked to bring her toes together. When measuring the external conjugate, the woman is asked to turn her back to the midwife and bend her lower leg (Fig. 12).
Pelvic planes.
In the pelvic cavity, four classical planes are conventionally distinguished (Fig. 13, Table 8).
Rice. 13.
Pelvic planes:
1
– anatomical conjugate;
2
– true conjugate;
3
– direct size of the wide part of the pelvic cavity;
4
– direct size of the narrow part of the pelvic cavity;
5
– direct size of the plane of exit from the pelvis during pregnancy;
6
– direct size of the plane of exit from the small pelvis during childbirth;
7
– wire pelvic spine
The 1st plane is called the entry plane. It is bounded anteriorly by the upper edge of the symphysis, posteriorly by the promontory, and laterally by the innominate line. The direct size of the entrance (between the middle of the upper inner edge of the symphysis and the promontory) coincides with the true conjugata ( conjugata vera
). In a normal pelvis, the true conjugate is 11 cm. The transverse dimension of the first plane - the distance between the most distant points of the boundary lines - is 13 cm. Two oblique dimensions, each of which is 12 or 12.5 cm, go from the sacroiliac joint to the opposite iliac joint - pubic tubercle.
Table 8
Pelvic planes
The plane of entrance to the small pelvis has a transverse oval shape.
The 2nd plane of the pelvis is called the latissimus plane. It passes through the middle of the inner surface of the pubis, sacrum and projection of the acetabulum. This plane has a rounded shape. The straight dimension, equal to 12.5 cm, goes from the middle of the inner surface of the pubic articulation to the articulation of the II and III sacral vertebrae. The transverse dimension connects the middles of the acetabular plates and is also 12.5 cm.
The 4th plane is called the exit plane and consists of two planes converging at an angle. In front it is limited by the lower edge of the symphysis (like the 3rd plane), on the sides by the ischial tuberosities, and behind by the edge of the coccyx. The direct size of the exit plane goes from the lower edge of the symphysis to the tip of the coccyx and is equal to 9.5 cm, and in the case of divergence of the coccyx, it increases by 2 cm. The transverse dimension of the exit is limited by the inner surfaces of the ischial tuberosities and is equal to 10.5 cm. When the coccyx diverges, this plane has longitudinal oval shape.
The wire line, or pelvic axis, passes through the intersection of the straight and transverse dimensions of all planes.
Internal dimensions of the pelvis
can be measured using ultrasound pelvimetry, which is not yet widely used.
With a vaginal examination, the correct development of the pelvis can be assessed. If the promontory is not reached during examination, this is a sign of a capacious pelvis. If the cape is reached, measure the diagonal conjugate
(the distance between the lower outer edge of the symphysis and the promontory), which normally should be no less than 12.5 - 13 cm (Fig. 14).
The internal dimensions of the pelvis and the degree of narrowing are judged by the true conjugate
(direct size of the entry plane), which in a normal pelvis is at least 11 cm.
The true conjugate is calculated using two formulas:
• The true conjugate is equal to the outer conjugate minus 9 – 10 cm.
• The true conjugate is equal to the diagonal conjugate minus 1.5 – 2 cm.
For thick bones, the maximum number is subtracted; for thin bones, the minimum number is deducted. To assess bone thickness, the Solovyov index
(wrist circumference). If the index is less than 14–15 cm, the bones are considered thin, if more than 15 cm, the bones are considered thick.
The size and shape of the pelvis can also be judged by the shape and size of the Michaelis diamond (Fig. 15), which corresponds to the projection of the sacrum. Its upper corner corresponds to the suprasacral fossa, the lateral corners correspond to the posterosuperior iliac spines, and the lower corner corresponds to the apex of the sacrum.
Rice. 14.
Diagonal conjugate measurement:
A
– first moment;
b
– second moment
The dimensions of the exit plane, as well as the external dimensions of the pelvis, can also be measured using a pelvis meter (Fig. 16).
Pelvic tilt angle
is the angle between the plane of its entrance and the horizontal plane. When a woman is in an upright position, it is 45–55 degrees. It decreases if the woman squats or lies in a gynecological position with her legs bent and brought toward her stomach (a possible position during childbirth). The same provisions allow you to increase the direct size of the exit plane. The angle of inclination of the pelvis increases if a woman lies on her back with a bolster under her back, or if she bends backward in an upright position. The same happens if a woman lies on a gynecological chair with her legs down (Walcher position). The same provisions allow you to increase the direct size of the entrance.
Rice. 15.
Michaelis rhombus:
A
– general view:
1
– depression between the spinous processes of the last lumbar and first sacral vertebrae;
2
– apex of the sacrum;
3
– posterosuperior iliac spines;
b
– shapes of the Michaelis rhombus with a normal pelvis and various anomalies of the bony pelvis (diagram):
1
– normal pelvis;
2
– flat pelvis;
3
– uniformly narrowed pelvis;
4
– transversely narrowed pelvis;
5
– obliquely narrowed pelvis
Rice. 16.
Measuring the dimensions of the pelvic outlet plane:
A
– transverse size;
b
– straight size
MENSTRUAL CYCLE AND ITS REGULATION
Menstruation, or cyclic bleeding from the uterus, occurs in every healthy woman or girl aged 12–13 to 50 years. Cyclic changes occur not only in the uterus, but throughout the entire body and are also cyclical in nature. Cyclic processes occur in the hypothalamus, pituitary gland, ovaries, uterus and other organs. This prepares the reproductive organs for pregnancy, childbirth and lactation.
Cortex.
Regulation of the menstrual cycle depends on the normal activity of the cerebral cortex and some subcortical formations (Fig. 17). Specialized neurons in the brain receive information about the state of the woman’s organs and the state of the external environment, convert it into neurohormonal signals, which enter the neurosecretory cells of the hypothalamus through the neurotransmitter system. The functions of neurotransmitters are performed by biogenic amines - catecholamines (dopamine and norepinephrine), indoles (serotonin), neuropeptides of morphine-like origin, opioid peptides (endorphins and enkephalins). The regulatory role of the cerebral cortex is not yet well understood. However, it has been noted that psycho-emotional experiences affect the regularity of the menstrual cycle. Stress can cause both a delay in menstruation and extraordinary bleeding. However, there have been cases where cyclical processes persisted in a woman in a coma. There are suggestions about the active participation of the amygdaloid nuclei and limbic system in the neurohumoral regulation of the menstrual cycle.
Hypothalamus.
The hypothalamus produces neurosecrets (liberins, or releasing factors) that affect the production of hormones in the anterior pituitary gland.
The following liberins have been studied:
• folliberin, or follicle-stimulating hormone releasing factor (FSH-RF);
• luliberin, or luteinizing hormone releasing factor (LH-RF);
• prolactoliberin, or prolactin releasing factor (PRF);
• corticoliberin, or adrenocorticotropic releasing factor (ACTH-RF);
Rice. 17.
Regulation of the menstrual cycle
• somatotropic releasing factor (STH-RF);
• thyrotropin-releasing hormone, or thyroid-stimulating releasing factor (T-RF);
• melanoliberin, or melanotropic releasing factor (M-RF).
The hypothalamus also produces neurosecretes (statins) that suppress the production of hormones from the anterior pituitary gland. The activity of the following statins has been studied:
• prolactostatin, or prolactin-inhibiting factor (P-IF);
• somatostatin, or somatotropic inhibitory factor (S-IF);
• melanostatin, or melanotropic inhibitory factor (M-IF).
As already mentioned, dopamine, norepinephrine, serotonin, endorphins and some other neurotransmitters can influence the production or inhibition of both neurosecretions of the hypothalamus and pituitary hormones.
The hypothalamus also synthesizes vasopressin, or antidiuretic hormone, and oxytocin, which are deposited in the posterior lobe of the pituitary gland (neurohypophysis).
The secretion of releasing factors, for example the secretion of gonadotropic releasing factors, is genetically programmed and formed during puberty. There is a programmed pulsating rhythm of the production of these secretions every hour, which is called circhoral, or hourly.
Pituitary.
The anterior lobe of the pituitary gland (adenohypophysis) produces gonadotropic hormones, i.e. hormones responsible for the production of sex hormones in the gonads.
The following hormones have been well studied:
• FSH – follicle stimulating hormone. It stimulates the growth and maturation of follicles in the ovary, promotes the proliferation of granulosa cells and the formation of LH receptors on the surface of these cells;
• LH is a luteinizing hormone, which, in combination with FSH, ensures ovulation and stimulates the synthesis of progesterone in the luteinized granulosa cells of the follicle (practically the corpus luteum). LH affects the synthesis of androgens, which can be converted into estrogens in a woman’s body;
Rice. 18.
The egg after ovulation (according to: Ailamazyan E.K., 2002):
1
- core;
2
– protoplasm;
3
– zona pellucida;
4
– follicular cells forming the corona radiata
• LTG is a luteotropic hormone, which has another name – prolactin. This hormone stimulates the growth of mammary glands and lactation, promotes the mobilization of fats. In high concentrations, it inhibits the growth and maturation of the follicle, ovulation and the onset of menstruation.
Gonadotropic hormones are produced in tonic and cyclic modes. Tonic – promotes the development of follicles and their production of estrogens. Cyclic – ensures a change in the phases of hormone secretion.
In addition, the anterior lobe of the pituitary gland produces: adrenocorticotropic hormone (ACTH), which mainly affects the function of the adrenal cortex; somatotropic hormone (GH), which stimulates growth, immune processes, and thyroid-stimulating hormone (TSH), which stimulates thyroid function. Melanotropin is produced in the middle lobe of the pituitary gland and is associated with adrenal function and affects mineralcorticoid metabolism.
Ovaries.
In the ovary of a sexually mature woman, under the influence of pituitary hormones, the follicle grows and matures, the egg matures and is born (this process is called
ovulation
) and sex hormones are produced (Fig. 18).
Even during the prenatal period, around the 20th week, germinal, or primordial, follicles are formed in the girl’s body. By the time of birth, there are from 300 thousand to 500 thousand. The primordial follicle consists of one egg surrounded by one row of follicular epithelium. Its diameter is about 50 microns.
Follicle growth occurs under the influence of follicle-stimulating hormone (FSH). The follicular epithelium multiplies, acquires a granular structure and forms a granulosa layer. The cells of this layer produce a secretion that accumulates in the intercellular space. The diameter of the follicle increases to 90 microns. The egg is pushed aside by the resulting fluid and is surrounded by granular cells in the form of a radiant crown ( corona radiata
).
This formation is called oviparous tubercle
. The liquid contains estrogenic hormones. These hormones promote the growth and better development of the uterus, mammary glands, and vagina; they can cause spontaneous contractions of the uterus and increase the sensitivity of the uterus to the action of contractile substances. The remaining granular cells are located along the periphery of the follicle and turn into a granulosa (granular) membrane. A connective tissue membrane (follicular) develops around it, which is divided into internal and external. The maturation of the egg occurs after double division. By this time, the follicle becomes mature and gradually transforms into a graafian vesicle, the size of which can reach 20 mm, while the membranes stretch from the surface, rupture and release the egg into the abdominal cavity. It is most likely that with a 28-day menstrual cycle, ovulation occurs on the 12th – 16th day. True, under the influence of hormonal influences, stress, illness, or taking medications, the time of ovulation may shift. At the site of the ruptured follicle, a corpus luteum forms.
If fertilization does not occur, the corpus luteum exists for 12–14 days and goes through the following stages of development:
• proliferation
, or growth;
• vascularization
, or proliferation of blood vessels;
• heyday
when the corpus luteum grows to its maximum size, it becomes folded;
• reverse development
when the corpus luteum gradually decreases and becomes discolored.
If pregnancy occurs, the corpus luteum functions during pregnancy and is called the “corpus luteum of pregnancy.”
The ovarian cycle is conventionally divided into two phases:
• follicular
, or estrogenic, - from the beginning of menstruation until ovulation, during which estrogens are produced;
• luteal
, or progesterone (can also be called gestagenic), - from ovulation to menstruation. At this stage, both estrogens and progesterone are produced, i.e. estrogens are produced throughout the entire cycle, and progesterone is produced mainly in the second half of the uterine cycle. It promotes relaxation of the uterine muscles, the growth of the pregnant uterus, and prepares the mammary glands for lactation.
The two-phase cycle is called ovulatory
. With a single-phase, or anovulatory, cycle (no ovulation), pregnancy cannot occur.
Estrogens are produced mainly by granular membrane cells.
Progestins are secreted by the luteal cells of the corpus luteum.
Androgens are secreted by the cells of the inner connective tissue membrane of the follicle ( theca interna
)
The processes in the ovary are cyclical and are regulated by the principle of direct and feedback, interconnected with the activity of the hypothalamus and pituitary gland. For example, an increase in the concentration of follicle-stimulating hormone (FSH) causes the growth and maturation of the follicle and contributes to an increase in the concentration of estrogen. Increased concentrations of estrogen can inhibit the production of FSH and promote the production of luteinizing hormone (LH), and LH together with FSH - ovulation. LH also promotes the development of the corpus luteum and the production of both progesterone and estrogens. The accumulation of progesterone in excess leads to a decrease in LH production. The production of female sex hormones by the ovary, together with cyclic changes in the pituitary gland and hypothalamus, causes cyclic processes in the uterus.
Uterus.
In women of reproductive age, menstrual discharge should be regular, moderately heavy, painless or slightly painful, most often occurring every 28 days, lasting 3 to 5 days. Normally, blood loss during these days should not be more than 100 ml.
Phases of the uterine cycle:
• desquamation
, or rejection of the functional layer of the endometrium, occurs within 3 to 5 days. This rejection is accompanied by blood loss of 50 to 100 ml and is called menstruation;
• regeneration
– healing of the bleeding surface, which lasts from the 6th to the 8th day, occurs under the influence of estrogens;
• proliferation
– restoration, or growth of the functional layer, also occurs under the influence of estrogens and continues until the 15th – 16th day;
• secretion
- occurs under the influence of progesterone and continues until the next menstruation.
Cyclic changes also occur in the vagina. For example, the thickness of the stratified squamous epithelium changes. During the uterine cycle, the diameter of the cervical canal and the viscosity of cervical mucus changes.
Cyclic changes occur not only in the genitals, but throughout the woman’s entire body: mood swings may be observed, especially in the period before menstruation, there may be fluctuations in body weight, temperature changes (by changes in rectal temperature, you can even determine the time of ovulation, since during During ovulation, the temperature rises by 0.5 degrees). There is some weight gain before menstruation, and during the same period there may be engorgement of the mammary glands. A woman can feel pain during menstruation and during ovulation, which is explained in the first case by the detachment of the functional layer of the uterine mucosa and contraction of the myometrium, and in the second case by microrupture of the ovary due to the release of the follicle.
Menstrual hygiene.
The midwife should give advice on menstrual hygiene and help the woman solve some problems associated with menstruation. The period of menstruation is a rather difficult time for a woman, at the same time it is a completely physiological phenomenon. It is necessary to give the woman advice on how to overcome discomfort and avoid complications.
At this time, it is not recommended to: be sexually active, do hard physical work, swim in ponds, take a bath, eat spicy food and alcohol. A woman should sleep more, drink more fluids and replace blood loss by eating high-calorie foods. It is necessary to strictly observe the rules of hygiene, take a shower and wash yourself more often, use frequently changed pads or tampons (for virgins, pads are preferable).
These recommendations should be followed in order to prevent complications both for the woman herself and for those around her. It should be remembered that transmission of infection is especially likely during this period. In Polynesia, during menstruation, a woman was taken to a special menstrual hut, which was then burned. According to all superstitions and beliefs, it was believed that a woman during menstruation was unclean and had to undergo a purification ceremony. With modern hygienic improvements, a woman can maintain a normal lifestyle and be fully able to work. In case of minor pain, she can take antispasmodics and analgesics. In cases of menstrual irregularities and particularly severe pain, she should consult a doctor 4
Problems of menstrual irregularities are dealt with in the Gynecology curriculum.
[Close].
Indications for computed tomography of organs located in the pelvis
CT allows you to examine the rectum, bladder and ureters, prostate gland in representatives of the stronger sex, as well as the uterus and vagina in women.
It is recommended to undergo such an examination if:
- pain in the pelvis and sacrum;
- injuries of bones and soft tissues;
- suspected pathology of the rectum;
- congenital disorders in the structure of the genitourinary system.
Another reason for undergoing such a diagnosis is infertility.
For men, CT scans are prescribed to diagnose benign and malignant tumors in the prostate area, prostatitis. In the fairer sex, endometriosis is detected using computed tomography. Women often undergo a CT scan if there is a suspicion of rupture of an ovarian cyst or capsule. Moreover, diagnostics in such cases is carried out on an emergency basis. A tomography examination is also indicated for vaginal bleeding, the cause of which is unclear.