Pituitary tumors - benign group, at least - of malignant neoplasms of the anterior lobe (adenohypophysis) and the posterior lobe (neurohypophysis) glands. Pituitary tumors, according to statistics, account for about 15% of intracranial tumors localization. They are often diagnosed equally in both sexes, usually between the ages of 30-40 years.
Symptoms
20% of patients have asymptomatic pituitary tumors that are detected only on autopsy. Clinical signs of pituitary tumors depend on hypersecretion of this or that hormone, size and growth rate of an adenoma. As the pituitary tumors are increasing, symptoms of the nervous and endocrine systems develop.
Increasing the size of the pituitary tumor leads to the development of the nervous system signs. As the pituitary gland is anatomically adjacent to the optic nerve (optic chiasm), then increasing the size of adenomas to 2 cm in diameter develop visual impairment: visual field loss, swelling of the papilla of the optic nerve and its atrophy, leading to a drop in vision, including blindness.
Pituitary adenomas of larger sizes cause compression of the cranial nerves, accompanied by symptoms of the nervous system: headache, diplopia, ptosis, nystagmus, limitation of movement of the eyeballs, convulsions, persistent cold, dementia and personality changes, increased intracranial pressure, bleeding in the development of the pituitary gland acute cardiovascular failure. With involvement of the hypothalamus may experience episodes of impaired consciousness.
Malignant tumors of the pituitary gland are extremely rare.
Classification
Pituitary tumors are classified according to their sizes, anatomic location, endocrine function, particularly the microscopic staining, etc. Depending on the size of tumors secrete microadenomas (less than 10 mm in maximum diameter) and macroadenomy (maximum diameter greater than 10 mm ) the pituitary. Localization in the anterior pituitary gland tumors are distinguished and posterior pituitary. Pituitary tumors in topography relative to sella and surrounding structures are endosellyarnymi ( going beyond the boundaries of Turkish saddle ) and intrasellyarnymi ( located within the sella ).
Taking into account the histological structure, the pituitary tumors are divided into benign and malignant tumors (adenomas). Adenomas originate from the glandular tissue of the anterior pituitary (adenohypophysis).
According to the functional activity, the pituitary tumors are divided into hormonally inactive ("dumb" insidentaloma) and hormonally active adenomas (producing a particular hormone), which are found in 75% of cases.
Risk Factors
Significant causes of pituitary tumors are not fully investigated, although it is known that some tumors may be genetically. The factors predisposing to the development of pituitary tumors include neural infections, chronic sinusitis, head injuries, hormonal changes (including as a result of prolonged use of hormonal drugs), adverse effects on the fetus during pregnancy.
Methods of treatment
Microsurgical removal of tumors with the use of intraoperative neuromonitoring
Endoscopic transnasal transsphenoidal biopsy access pituitary adenomas using intraoperative neuronavigation system
