“Empty sella” syndrome - is this disease dangerous?

MRI is a non-invasive, highly informative, safe study. As a result of the procedure, a three-dimensional model of the area of ​​interest is obtained, assembled from many slices.

Anatomy of the brain: the pituitary gland is located in the saddle-shaped prominence of the sphenoid bone

In neurosurgery, endocrinology and neurology, MRI of the brain/sella turcica is prescribed if a pathological process in the pituitary gland is suspected. The absence of ionizing radiation harmful to humans allows magnetic resonance scanning to be carried out for pregnant women from the 12th week of gestation and for newborns upon reaching the age of one month.

Why is MRI of the sella turcica prescribed?

This anatomical structure is the seat of the pituitary gland, an endocrine gland that regulates metabolic processes in the body. The sella turcica (protrusion on the body of the sphenoid bone) protects the cerebral appendage from mechanical damage and compression.

If a tumor of the pituitary gland is suspected and there is a need to assess the blood supply to the structure, MRI is performed with intravenous contrast. Diagnosis of the phenomenon of an empty sella turcica, arachnoid cysts, and funnel deformation does not imply the introduction of an amplifier. The type of study is determined by the doctor, based on the clinical picture, changes in tests, and previous diagnostic data.

Is it possible to do an MRI of the sella turcica?

Magnetic resonance imaging of the brain

You can undergo a diagnostic procedure on the direction of a doctor, including under a compulsory medical insurance/voluntary health insurance policy, or independently, provided there are no contraindications:

• functioning implants with metal components, vascular clips, ferromagnetic fragments, etc.;
• body weight more than 120 kg;
• pregnancy in the first trimester;
• emergency condition - cardiovascular accidents, acute abdomen, etc.
• mental illness that prevents MRI (can be examined in a hospital under sedation).

Contrast is unacceptable in cases of severe renal failure (GFR less than 30 ml/min) or allergies to an enhancer drug.

What is better to do: MRI or CT of the sella turcica?

Magnetic resonance scanning will be more informative if pathology of the pituitary gland/hypothalamus and surrounding soft tissues is suspected; computer scanning will better show changes in solid bone structures and foci of calcification.

Biologically active substances synthesized by the pituitary gland

Indications for the study:

• increased levels of prolactin and other hormones;
• empty sella syndrome according to computed tomography results, suspected focal formation;
• clinical manifestations of pituitary gland dysfunction: neurological, endocrine, ophthalmosymptoms:

• stunting/gigantism;
• thirst, excessive urination;
• causeless loss of body weight;
• moon-shaped face;
• excessive sweating, deterioration in the appearance of skin, hair, nails;
• infertility/changes in spermogram;
• menstrual irregularities;
• erectile disfunction;
• increased blood pressure, dizziness;
• mood swings, etc.;

• dynamic monitoring of asymptomatic tumors;
• assessment of post-traumatic changes, etc.

Features of interpretation of survey results

The resulting images - lateral and frontal craniograms - are analyzed by a radiologist.

The main categories used in the process of decoding images:

• sagittal size;
• vertical size;
• sella turcica shape;
• location, shape and dimensions of the saddle back.

For an objective analysis of the results, the images must be recorded taking into account the requirements of correct placement and centering. Correctness is determined by the complete coincidence of the projections of the anterior sphenoid processes, internal and external auditory openings.

Normally, the plane of the sphenoid eminence and the pituitary fossa in the sella turcica are visualized on photographs as single lines with a clear, intense contour.

D. G. Rokhlin proposed his own method for assessing the size of the pituitary fossa of the sella turcica from X-ray images. For this purpose, an image of the skull in a frontal projection is used. The Rokhlin technique is considered one of the most objective and accurate schemes.

The sagittal dimension is defined as the maximum distance between the posterior and anterior walls of the fossa. In this case, the line that connects the outermost points of the fossa has a direction parallel to the plane of the wedge-shaped eminence. The normal sagittal size in an adult is no more than 14 millimeters.

The process of clarifying the vertical size of the fossa is impossible without drawing a projection line of the diaphragm of the sella turcica on the image. Normally, it connects the middle and posterior sphenoid processes. If the media are not visualized on the image, the projection is determined by connecting the tubercle sella and the posterior processes. In some cases, for example, in children, the posterior sphenoid processes may not be visible on the radiograph, so the projection is carried out by connecting the tubercle sella and the top of the dorsum sella with a line. In addition to this line, an auxiliary tangent line is established to the lowest point of the edge of the pituitary fossa. It is located parallel to the surface of the wedge-shaped eminence. A perpendicular is laid from the indicated tangent to the midpoint of the bottom of the pituitary fossa. The vertical size of the fossa is measured from the tangent to the intersection of the perpendicular with the projection of the diaphragm. Its normal length is up to 12 millimeters.

The shape of the sella turcica is a very individual category. In order to be able to generalize and evaluate it, scientists were proposed to calculate the sella index - the ratio of the vertical and sagittal dimensions. A flat fossa is one in which the sagittal dimension is larger than the vertical. If both dimensions are equal, the hole is considered round. If the larger size is vertical, then the hole is deep.

It is noteworthy that both sizes of the fossa tend to change, starting from childhood until the end of the organism’s maturation, and the sagittal size can increase even after the entire organism stops growth processes.

In children under 2-3 years of age, a flat shape of the pituitary fossa is usually found. By the age of 4-5 years, the vertical size becomes equal to the sagittal one, that is, the fossa acquires a round shape, and then acquires a larger size than the sagittal one. The round or deep shape of the fossa, starting from this age, persists up to 15 years in boys and up to 8 years in girls, after which the sagittal size begins to rapidly increase, which is why in adults the flat shape of the pituitary fossa sellae can most often be found on the picture.

The back of the saddle in the pictures appears as a flat or concave clear line. Basically, it has a vertical location, but a slight tilt forward or backward is allowed. Its thickness ranges from 1 to 10 millimeters.

To study the features of the shape and location of the back of the sella turcica, the doctor needs to have targeted radiographs in the nasal-frontal and posterior occipital projections. In such photographs, the back is defined as a rectangle that expands slightly upward. The transverse size of the back in an adult can reach 15 millimeters.

In addition to these values, the radiologist also pays attention to the structure of the wedge-shaped processes. The front ones are usually equal in size, while the rear ones can be located at different angles or vertically, and have different sizes. Technically correct images also show the middle sphenoid processes.

Will an MRI show an empty sella turcica?

MRI image of the area of ​​interest

When interpreting photographs of magnetic resonance imaging of the head, the phenomenon of an empty sella turcica is often discovered by chance.

The pituitary gland is separated from the hypothalamus by a stalk that passes through an opening in the dura mater. Above are the diaphragm and the space filled with cerebrospinal fluid. If the membrane fails, fluid enters the sella turcica. High intracranial pressure and the invasion of the meninges have a compressive effect on the pituitary gland, as a result of which the gland is spread out along the walls. With long-term pathology, deformation (flattening) of bone structures occurs, as shown by MRI.

The phenomenon of an empty sella turcica may be a consequence of:

• hormonal changes;
• pituitary ischemia;
• autoimmune pathologies;
• past illnesses, injuries;
• post-radiation changes in the chiasmal-sellar region;
• adenoma necrosis and hemorrhage;
• operations for tumors.

The clinical picture is variable: from the absence of symptoms to severe manifestations of intracranial hypertension:

• headache;
• nausea;
• hearing impairment;
• memory impairment, etc.

Above the sella turcica there is a chiasma (optic chiasm), therefore, with compression of this structure, the appearance of ophthalmological symptoms is typical: decreased visual acuity, double vision, loss of fields, lacrimation.

Differentiation is carried out with:

• craniopharyngioma;
• arachnoid, epidermoid, Ratkin cysts;
• multicavitary pituitary adenoma.

Definition

The sella turcica is a formation in the bone structure of the skull that houses the most important area of ​​the brain responsible for the production of hormones (prolactin, somatotropin, lipotropin, luteinizing, follicle-stimulating, thyroid-stimulating hormones), which determines its leading role in the endocrine system. The sella turcica in humans is located in the central part of the cranium, where the base of the skull is located. In the area of ​​the sella turcica, called in Latin as sella turcica, the optic nerves lie.

How to prepare for an MRI of the sella turcica?

Eating a light meal 30 minutes before contrast will help prevent nausea, dizziness, drooling, and metallic taste.

In most medical centers, diagnostics are carried out by appointment. When planning a native study, no special measures are required: it is enough to rest well before the procedure and choose clothes without metal parts.

Women during lactation are advised to stock up on milk for 2-3 feedings; within 24 hours, the contrast agent will completely leave the body.

Before an MRI scan, it is better to refrain from drinking alcohol and smoking.

The clinic will require the following documents:

• passport;
• doctor's referral indicating the preliminary diagnosis, area and type of examination (with or without contrast);
• extracts from the medical record, hospital, conclusion of the oncology consultation;
• results of previously performed MRI, CT, radiography.

Treatment of other diseases starting with the letter - s

The information is for educational purposes only. Do not self-medicate; For all questions regarding the definition of the disease and methods of its treatment, consult your doctor. EUROLAB is not responsible for the consequences caused by the use of information posted on the portal.