The elements located in the area of the sella turcica are difficult to examine. Neither externally nor with the help of x-ray examination can one detect pathologies in this area of the brain. Preparing for an MRI of the pituitary gland does not mean that significant disruptions have occurred in the body.
The main advantages of tomography using a magnetic resonance machine are:
- possibility of three-dimensional examination
- absence of foreign elements (skull bones) in the image
- correct visualization of vessels, both arterial and venous
- accurate diagnosis of the degree of movement of the chiasm
- harmless to the body
Anatomical features of the pituitary gland
The pituitary gland belongs to the group of so-called central glands of the body. The hypothalamus and pineal gland are included in this category. Located at the base of the human skull, the pituitary gland has two lobes - posterior and anterior. The mass of the pituitary gland is no more than one gram, and its dimensions do not exceed 3-8 mm in height and 10-17 mm in width. The outer surface of the pituitary gland is either completely flat or slightly concave. In rare cases, it becomes convex, most often this happens in young women.The pituitary gland produces hormones that are essential for regulating numerous processes - physiological and biological. The anterior lobe produces tropic hormones, which are necessary for the induction of hormones in other glands and influence reactions in almost all tissues of the body. Fluid balance and muscle tone are constantly regulated by hormones from the pituitary lobe, located posteriorly.
The lobe located in front produces a whole group of hormones: thyrotropin, prolactin, luteinizing and follicle-stimulating hormones, melatropin and lipotropin.
Indications for MRI
Indications for MRI of the pituitary gland include suspicion of the occurrence of pathologies in the pituitary gland. If there is concern that a tumor is developing in the organ or there are disorders in the sellar region that cannot be detected in any other way, MRI of the pituitary gland with contrast is recommended. Contrasting is the procedure for introducing a special fluid into the body, which accumulates in the damaged organ and at the same time clearly outlines its contours. This method allows you to track the full picture of the structure of the pituitary gland and make a correct diagnosis.The main indications are:
- assumption of the presence of an adenoma
- suspicion of the development of Cushing's syndrome (with pronounced obesity with stretch marks on the skin)
- assumption of increased hormonal activity as a result of the tests performed
- increased prolactin levels
- pathological abnormalities in the functioning of other glands
Pathological changes in the pituitary gland can provoke growth disturbances and cause manifestations of dwarfism or gigantism. Adenomas of this organ are most often benign, but in order to avoid their development into malignant, they should be examined for further treatment. To do this, you need to prepare for an MRI of the pituitary gland, because only resonance scanning allows you to correctly diagnose and carry out appropriate treatment.
Carrying out an MRI procedure
Magnetic resonance imaging examination of pathologies of the pituitary gland is carried out together with the surrounding area, since its size is very small. It is difficult to accurately determine changes in the pituitary gland, which can only affect its individual parts. Therefore, images of maximum resolution are needed. The special protocol for studying the pituitary gland differs significantly from the protocol for MRI of the brain.Since MRI is performed in special apparatus, which has magnetic resonance properties, before the procedure you should remove all metal components from clothing (buckles, brooches) and metal jewelry. If there is a piercing, it will have to be removed in advance. Metal prostheses should also be removed.
Preparing for an MRI of the pituitary gland with contrast involves testing the injected substance to detect the presence of allergic reactions. A special contrast agent is administered before the procedure. It can be administered once before the start of the study (half an hour). Sometimes contrast is administered through an IV during the entire examination.
The patient is placed inside the device in a supine position with the head securely fixed. You cannot move during the examination. The usual time for resonance imaging of the pituitary gland is about an hour.
Contraindications for MRI of the pituitary gland
The numerous advantages of resonance tomography do not exclude the presence of contraindications, which can be divided into absolute (a complete ban on the procedure) and relative (the advisory nature of the ban).Relative contraindications to MRI of the pituitary gland are the presence of non-metallic implants, heart failure, and nerve stimulators. This group also includes obesity and claustrophobia, which are directly related to the procedure - the need to place the subject in the apparatus.
MRI is not performed for people who have metal implants, pacemakers, or implanted ferromagnetic implants.
MRI of the pituitary gland should be performed with caution during pregnancy, only if absolutely necessary. And the tomography procedure with contrast is completely contraindicated for this category.
Magnetic resonance imaging - modern direction instrumental study of the human body. The high information content of the resulting images makes it possible to early stage detect pathologies and neoplasms, even if the size of the area being examined is very small. MRI of the brain, including the pituitary gland, is widely used to detect tumors.
The pituitary gland (pituitary gland) is a small gland that is located under the cerebral cortex, in the pituitary fossa of the sella turcica. Its functions include the production and secretion of hormones involved in the metabolic processes of the body. The posterior and anterior lobes of the pituitary gland are located at the base of the brain where, despite their small size, they produce many different hormones. Any pathology in the structure of the pituitary gland leads to disruption hormonal levels and consequently, to the occurrence of various diseases.
Due to the inaccessibility of ultrasound or x-ray examination and its small size, magnetic resonance imaging of the pituitary gland is a real godsend for doctors.
What is the essence of the method?
The image in magnetic resonance imaging is formed as a result of the reaction of hydrogen atoms present in any organ human body, to electromagnetic pulses. To determine changes in the tissues of the pituitary gland during the scanning process, the MRI machine creates layer-by-layer images of the gland. This is comparable to the thinnest sections, each of which is depicted in the photograph. Thus, the doctor has the opportunity to see the slightest changes in the structure of the pituitary gland.
Indications for the study
The doctor prescribes an MRI of the pituitary gland if the patient has the following signs of gland dysfunction:
- menstrual irregularities;
- a significant increase in prolactin levels;
- pronounced obesity with characteristic stretch marks (stretch marks) on the skin;
- blurred vision, changes in visual fields, impaired eye motility;
- frequent headaches not associated with other diseases;
- memory and orientation problems.
What does an MRI of the pituitary gland show?
As a result of the study, the doctor can diagnose changes in the structure and size of the pituitary gland and determine the cause of the following diseases:
- infertility;
- diabetes insipidus;
- acromegaly or gigantism;
- tumor process;
- thyrotoxicosis;
- metabolic disorders, etc.;
MRI also reveals the type of tumor, if present. An adenoma is often diagnosed - a benign tumor, which, even if small in size, can be easily treated drug treatment. A large adenoma must be surgically removed. A malignant tumor of the pituitary gland is very rarely diagnosed.
Order of conduct
To obtain high-quality images of the pituitary gland, scanning is recommended to be performed on closed-type devices with a high field. During the session, the patient lies on the mobile table of the MRI machine, which is then moved inside the chamber. The patient does not experience any impact from the tomograph, except for the loud noise that the tomograph makes during scanning. The duration of the procedure is thirty to forty minutes, during which you need to remain motionless. When contrast is used, the examination lasts about an hour.
When is an MRI of the pituitary gland with contrast prescribed?
The use of contrast in magnetic resonance imaging is recommended for patients with suspected pituitary malignancy. In some cases, the doctor may prescribe contrast to identify microadenomas or to identify the interaction of the tumor with surrounding tissues.
The use of a dye (usually gadolinium) makes it possible to more accurately highlight the gland itself and tumors, infections or other abnormalities in the images, which greatly facilitates the diagnosis of changes in the gland.
MRI of the pituitary gland with contrast can be performed in two ways: with the administration of the drug half an hour before the examination, or with the drip administration of a contrast agent during the procedure. You should arrive for the procedure on an empty stomach.
To look for microadenomas, dynamic MRI is sometimes used, in which a series of images are taken within a few minutes immediately after contrast is administered. This type of scan is based on the fact that tumors and normal gland tissue absorb dye at different rates.
Dynamic MRI is especially important for the search for adenomas causing acromegaly or when Cushing's disease is suspected.
Advantages of the MRI method
- It is safe even when performed repeatedly, as it does not expose the patient to ionizing radiation.
- The most informative of modern hardware for diagnosing the condition of the pituitary gland, which cannot be compared with ultrasound, X-ray, or CT.
- Detects any change in the structure and condition of an organ.
- MRI using contrast is much less likely to cause side effects and allergic reactions than the contrast agents used in CT.
Contraindications to the procedure
The main contraindication to MRI is the presence of implanted medical devices in the patient:
- pacemakers;
- drivers of the heart;
- brain clips and others.
There is a risk of an acute allergic reaction to the contrast agent, so an allergic reaction test is done before the procedure.
Patients with kidney pathologies may be harmed by high doses of contrast media. In rare cases, gadolinium has been shown to cause nephrogenic systemic fibrosis.
There are limitations to the use of contrast-enhanced MRI in breastfeeding mothers. It is not recommended to carry out breast-feeding within two days after contrast administration.
In case of severe claustrophobia (fear of closed spaces), scanning is carried out in open-type tomographs or sedatives are used.
If you have been prescribed an MRI of the pituitary gland, the question arises - how to prepare? MRI is a rather complex, expensive procedure; it helps to identify changes in organs located in the very depths of the brain, in the skull. These changes are difficult to recognize using other research methods, which is why patients are prescribed MRI, because it allows one to study the metabolic processes of cells and blood supply.
What are the features of MRI of the pituitary gland, how to prepare for it
When you are scheduled for this examination, you need to prepare for an MRI of the pituitary gland with special care. The pituitary gland is a small gland that is located in the skull. It produces a number of hormones that affect the tissues of the human body. Typically, MRI is prescribed for gland dysfunction, if the pituitary gland is not working properly - its hypofunction or hyperfunction is pronounced.
An MRI may be prescribed for:
- the patient’s complaints of frequent headaches, the nature of which is not clear;
- visual impairment or symptoms associated with defects in the innervation of the extraocular muscles (the pituitary gland is located near the site of the optic nerve);
- weight changes (obesity or cachexia), metabolic disorders, since the pituitary gland produces thyroid-stimulating hormone, which affects metabolism;
- absence or irregularities in the frequency of menstruation in women, caused by problems in the pituitary gland's production of follicle-stimulating and luteinizing hormones, which ensure the normal functioning of the female genital organs;
- erectile dysfunction in men, which can also be a sign of cerebrovascular accident;
- acromegaly;
- the presence of hypercortisolism syndrome, when differential diagnosis of Itsenko-Cushing's disease is needed.
These deviations are caused by both hyperfunction and hypofunction of the glandular tissue of the pituitary gland. Often such disorders occur against the background of the formation of a tumor, which can be benign (adenoma) or malignant (adenocarcinoma).
How to properly prepare for an MRI of the pituitary gland?
Preparing for the scan is not difficult, since MRI of the pituitary gland does not require special preparation: for example, food intake will not affect its examination in any way. However, if you are offered an MRI of the pituitary gland with contrast, then you need to prepare by refusing to eat four hours before the scan. This is due to the fact that the contrast agent has side effects and may cause dyspeptic symptoms such as nausea or vomiting. The chance of their occurrence is higher if the patient's stomach is full of food.
Before preparing for an MRI of the pituitary gland, tell your doctor if you have asthma or are allergic to medications, since the contrast agent can provoke an attack. Take with you to the clinic the results of previously completed additional studies, including blood tests for hormones - this will help the specialist to determine in advance which part of the pituitary gland can be changed.
How to prepare for an MRI of the pituitary gland with contrast? No special preparation is needed, just don’t eat four hours before the procedure and notify your doctor if you have allergies to medications or bronchial asthma.
MRI of the pituitary gland or brain - which method of examination is preferable to identify pathological changes in the pituitary gland? The question is logical, since this gland in the brain (on its lower surface) is visualized during examination of the latter. However, due to differences in indications and protocols, these MRI options cannot be identified.
What is an MRI examination of the pituitary gland or brain?
MRI (magnetic resonance imaging) of the pituitary gland, brain or any other organ is a highly informative diagnostic method based on interaction magnetic field and hydrogen atoms contained in the tissues being studied. Visualization of the examined anatomical structures using magnetic resonance technology does not involve radiation exposure, therefore it is considered safer than radiography and computed tomography (or CT).
In the diagnosis of diseases of the central nervous system (central nervous system) magnetic resonance imaging plays a leading role, as it gives doctors information about soft tissue damage, neoplasms, and changes in the vascular bed. Based on the MRI results, specialists determine treatment tactics, and if surgery is indicated, choose the optimal surgical option.
Tomography of the pituitary gland or brain: reasons for the examination
The pituitary gland produces hormones that regulate important physiological processes, so when its functioning is disrupted, serious diseases develop: nanism, acromegaly, hypothyroidism, infertility, diabetes insipidus, obesity.
Most often, tumors (adenomas) and empty sella syndrome lead to pituitary secretory dysfunction. MRI is best suited for diagnosing these or other pathologies, and a similar procedure for analyzing the brain has a slightly different purpose.
When is it better to diagnose the brain or pituitary gland?
Brain research is used in cases where it is necessary to determine the cause of constant pain in the head, fainting, memory loss, progressive visual and hearing impairment, seizures, and paralysis. Also using this method It is possible to study brain structures in different projections and diagnose the following pathological conditions with high accuracy:
- tumors;
- strokes;
- aneurysms and vasoconstriction;
- multiple sclerosis;
- bruises and displacements of brain structures.
Are the examination procedures different or not?
MRI of the pituitary gland differs from MRI of the brain in the object of study, indications, as well as general or technical parameters (projection, slice thickness, image resolution). Everything else is identical: a high-precision device with a closed circuit is used, a contrast agent is applied if necessary, the diagnostic process lasts 30-60 minutes, and contraindications common to all magnetic resonance methods can prevent it from being carried out.
Is it possible or not to replace MRI of the pituitary gland with magnetic resonance imaging of the brain?
MRI of the pituitary gland cannot be replaced by magnetic resonance scanning of the brain, or the information obtained will be uninformative. The pituitary lobes are small in size, so high-resolution images with minimal thickness are required to detect pathological processes in them. In such images, the doctor can examine the smallest adenomas (microadenomas), which are not visualized on overview images of brain structures.
The answer to the question, “Which is better: MRI of the pituitary gland or the brain?” is clear - it depends on the circumstances. Due to the frequent clinical need to study in more detail the area of the sella turcica or the pituitary lobes, diagnostic centers provide MRI of the pituitary gland as a separate service. Therefore, the doctor always has the opportunity to prescribe exactly what is indicated for the patient.
MRI is often used to evaluate the internal structures of the brain. MRI of the pituitary gland, as a rule, is prescribed for the diagnosis of pituitary tumors. Currently MRI examination of the pituitary gland is the best method for diagnosing changes in the pituitary gland and nearby structures and allows you to obtain images of higher quality than other research methods. Considering that tumors and changes in the pituitary gland are small, only MRI examination using high-field MRI allows obtaining images with high resolution. MRI is often performed with the use of contrast, which makes it possible to more clearly visualize even minor morphological changes in such a small organ as the pituitary gland.
The pituitary gland is a small oval-shaped gland that is located at the base of the skull below the optic nerve. The pituitary gland produces hormones that control and regulate other endocrine glands in the body. These glands secrete hormones that control metabolism and tissue growth.
The pituitary gland consists of two lobes: anterior and posterior.
The anterior pituitary gland produces six hormones:
- Growth hormone (somatotropic hormone)
- Prolactin, a hormone that stimulates breast milk production after childbirth
- ACTH (adrenocorticotropic hormone), which stimulates the production of adrenal hormones
- TSH (thyroid-stimulating hormone), which stimulates the production of thyroid hormones
- FSH (follicle stimulating hormone) and LH (luteinizing hormone), which stimulate the ovaries in women and the testes in men.
The posterior lobe of the pituitary gland produces:
- ADH (antidiuretic hormone), reduces urine production
- Oxytocin, which stimulates uterine contractions during labor and the release of breast milk.
Indications for MRI of the pituitary gland
- Headaches of unsophisticated origin
- Visual impairment (changes in visual fields)
- Eye movement disorders
- Intracranial hypertension
- Increased or altered hormone production and associated endocrine disorders.
Contraindications for MRI of the pituitary gland:
- presence of metal in the body
- pregnancy
- CRF (if necessary, studies with contrast).
MRI of the pituitary gland allows you to diagnose formations such as:
Microadenoma – Tiny tumors (less than 10 mm). As a rule, these are tumors of the anterior pituitary gland and in such cases there is excessive secretion of prolactin. Craniopharyngioma - These pituitary tumors usually occur in young children and cause symptoms related to pressure on nearby structures. These tumors put compression on the optic nerves, which will result in blurred vision, or put pressure on the brain, which can lead to intracranial hypertension and headaches.
Pituitary cyst – Most pituitary cysts are asymptomatic. But if the cyst is large, then a compression effect on the brain structures is possible with the development of headaches.
Pituitary apoplexy - Some pituitary tumors can bleed and destroy large parts of the pituitary gland, leading to severe endocrinological disturbances. If blood circulation is impaired, dyshormonal disorders can also be serious. In such cases, we are talking about a stroke of the pituitary gland and sometimes this can pose a risk to life.
In some cases, with a small tumor size, dynamic MRI may be performed. In dynamic MRI, a series of images are taken immediately within a few minutes of gadolinium administration. This type of study is based on the different levels of gadolinium (contrast) absorption between healthy and diseased tissue.