Brain and spinal cord tumours.pptx

medical

1. PRIMARY BRAIN TUMORS Mrs.Usha Rani Kandula , Assistant professor, Department of nursing, Arsi University, Asella , Ethiopia.

2. PRIMARY BRAIN TUMORS A brain tumor is a localized intracranial lesion that occupies space within the skull. Tumors usually grow as a spherical mass, but they can grow diffusely and infiltrate tissue. The effects of neoplasms occur from the compression and infiltration of tissue. A variety of physiologic changes result, causing any or all of the following pathophysiologic events:

3. Increased intracranial pressure (ICP) and cerebral edema Seizure activity and focal neurologic signs Hydrocephalus Altered pituitary function

4. Primary brain tumors originate from cells and structures within the brain. Secondary , or metastatic, brain tumors develop from structures outside the brain and occur in 20% to 40% of all patients with cancer. Brain tumors rarely metastasize outside the CNS , but metastatic lesions to the brain occur commonly from the lung, breast, lower gastrointestinal tract, pancreas, kidney, and skin (melanomas).

5. The cause of primary brain tumors is unknown. The only known risk factor is exposure to ionizing radiation. Both glial and meningeal neoplasms have been linked to irradiation of the cranium , with a latency period of 10 to 20 years after exposure. Suggested causes have included use of cellular telephones, exposure to high-tension wires, use of hair dyes, head trauma, dietary exposure to such factors as nitrates, and other sources.

6. Secondary tumors or metastases to the brain from a systemic primary cancer are more common. In adults, most brain tumors originate from glial cells (glial cells make up the structure and support system of the brain and spinal cord) and are supratentorial (located above the covering of the cerebellum). Neoplastic lesions in the brain ultimately cause death by impairing vital functions, such as respiration, or by increasing intracranial pressure (ICP).

7. GLIOMAS Glial tumors, the most common type of brain neoplasm, are divided into many categories. Astrocytomas are the most common type of glioma and are graded from I to IV, indicating the degree of malignancy. The grade is based on cellular density, cell mitosis, and appearance. Usually , these tumors spread by infiltrating into the surrounding neural connective tissue and therefore cannot be totally removed without causing considerable damage to vital structures.

8. Oligodendroglial tumors are another type of glial tumor, representing 20 % of gliomas . MENINGIOMAS Meningiomas , which represent 20% of all primary brain tumors, are common benign encapsulated tumors of arachnoid cells on the meninges. They are slow-growing and occur most often in middle-aged adults (more often in women ). Meningiomas most often occur in areas proximal to the venous sinuses. Manifestations depend on the area involved and are the result of compression rather than invasion of brain tissue . Standard treatment is surgery with complete removal or partial dissection.

9. ACOUSTIC NEUROMAS An acoustic neuroma is a tumor of the eighth cranial nerve, the cranial nerve most responsible for hearing and balance. It usually arises just within the internal auditory meatus, where it frequently expands before filling the cerebellopontine recess . As the tumor becomes larger, painful sensations of the face may occur on the same side as a result of the tumor’s compression of the fifth cranial nerve.

10. With improved imaging techniques and the use of the operating microscope and microsurgical instrumentation, even large tumors can be removed through a relatively small craniotomy . Some of these tumors may be suitable for stereotactic radiotherapy rather than surgery.

11. PITUITARY ADENOMAS Pituitary tumors represent about 8% to 12% of all brain tumors and cause symptoms as a result of pressure on adjacent structures or hormonal changes ( hyperfunction or hypofunction of the pituitary ).

12. Pressure Effects of Pituitary Adenomas Pressure from a pituitary adenoma may be exerted on the optic nerves, optic chiasm, or optic tracts or on the hypothalamus or the third ventricle when the tumor invades the cavernous sinuses or expands into the sphenoid bone . These pressure effects produce headache, visual dysfunction, hypothalamic disorders ( eg , disorders of sleep, appetite, temperature and emotions), increased ICP, and enlargement and erosion of the sella turcica .

13. Hormonal Effects of Pituitary Adenomas Functioning pituitary tumors can produce one or more hormones normally produced by the anterior pituitary. These hormones may cause prolactinsecreting pituitary adenomas ( prolactinomas ), growth hormonesecreting pituitary adenomas that produce acromegaly in adults, and adrenocorticotropic hormone (ACTH)-producing pituitary adenomas that result in Cushing’s disease.

14. ANGIOMAS Brain angiomas (masses composed largely of abnormal blood vessels) are found either in or on the surface of the brain .

15. Clinical Manifestations Brain tumors can produce either focal or generalized neurologic signs and symptoms. Generalized symptoms reflect increased ICP , and the most common focal or specific signs and symptoms result from tumors interfering with functions in specific brain regions.

16. INCREASING ICP The skull is a rigid compartment containing essential noncompressible contents: brain matter, intravascular blood , and cerebrospinal fluid (CSF ). Brain components increases in volume, ICP increases unless one of the other components decreases in volume. Consequently , any change in volume occupied by the brain (as occurs with disorders such as brain tumor or cerebral edema) produces signs and symptoms of increased ICP.

17. Common brain tumor sites

18. Symptoms of increased ICP result from a gradual compression of the brain by the enlarging tumor . The effect is a disruption of the equilibrium that exists between the brain, the CSF, and the cerebral blood, all located within the skull. As the tumor grows, compensatory adjustments may occur through compression of intracranial veins, reduction of CSF volume (by increased absorption or decreased production), a modest decrease of cerebral blood flow, and reduction of intracellular and extracellular brain tissue mass.

19. The three most common signs of increased ICP are headache, nausea and vomiting , and a sixth-nerve palsy. Personality changes and a variety of focal deficits, including motor, sensory, and cranial nerve dysfunction, are also common.

20. LOCALIZED SYMPTOMS The most common focal or localized symptoms are hemiparesis, seizures , and mental status changes. When specific regions of the brain are affected, additional local signs and symptoms occur, such as sensory and motor abnormalities, visual alterations , alterations in cognition, and language disturbances such as aphasia. The progression of the signs and symptoms is important because it indicates tumor growth and expansion. For example , a rapidly developing hemiparesis is more typical of a highly malignant glioma than a low-grade tumor.

21. Assessment and Diagnostic Findings The history of the illness and the manner and time frame in which the symptoms evolved are key components in the diagnosis of brain tumors. A neurologic examination indicates the areas of the CNS involved. To assist in the precise localization of the lesion , a battery of tests is performed. Computed tomography (CT ) scans, enhanced by a contrast agent, can give specific information concerning the number, size, and density of the lesions and the extent of secondary cerebral edema.

22. CT scans can provide information about the ventricular system. Magnetic resonance imaging (MRI) is the most helpful diagnostic tool for detecting brain tumors, particularly smaller lesions, and tumors in the brain stem and pituitary regions, where bone interferes with CT . Positron emission tomography (PET ) Cerebral angiography provides visualization of cerebral blood vessels and can localize most cerebral tumors.

23. An electroencephalogram (EEG) can detect an abnormal brain wave in regions occupied by a tumor and is used to evaluate temporal lobe seizures and assist in ruling out other disorders . Cytologic studies of the CSF may be performed to detect malignant cells because CNS tumors can shed cells into the CSF .

24. Medical Management A variety of medical treatment modalities, including chemotherapy and external-beam radiation therapy, are used alone or in combination with surgical resection. Radiation therapy, the cornerstone of treatment of many brain tumors, decreases the incidence of recurrence of incompletely resected tumors. Brachytherapy (the surgical implantation of radiation sources to deliver high doses at a short distance) has had promising results for primary malignancies .

25. Intravenous (IV) autologous bone marrow transplantation is used in some patients who will receive chemotherapy or radiation therapy because it has the potential to “rescue” the patient from the bone marrow toxicity associated with high doses of chemotherapy and radiation . A fraction of the patient’s bone marrow is aspirated, usually from the iliac crest, and stored . The patient receives large doses of chemotherapy or radiation therapy to destroy large numbers of malignant cells. The marrow is then reinfused intravenously after treatment is completed.

26. Corticosteroids may be used before and after treatment to reduce cerebral edema and promote a smoother, more rapid recovery. Gene-transfer therapy uses retroviral vectors to carry genes to the tumor, reprogramming the tumor tissue for susceptibility to treatment. This approach is being tested.

27. A new technique being investigated is photodynamic therapy. This is a treatment of primary malignant brain tumors that delivers a targeted therapy while conserving healthy brain tissue.

28. SURGICAL MANAGEMENT The objective of surgical management is to remove or destroy the entire tumor without increasing the neurologic deficit ( paralysis, blindness ) or to relieve symptoms by partial removal (decompression). A variety of treatment modalities may be used; the specific approach depends on the type of tumor, its location, and accessibility. Most pituitary adenomas are treated by transsphenoidal microsurgical removal, whereas the remainder of tumors that cannot be removed completely are treated by radiation. An untreated brain tumor ultimately leads to death, either from increasing ICP or from the damage to brain tissue it causes.

29. Conventional surgical approaches require an incision into the skull (craniotomy ). This approach is used in patients with meningiomas , acoustic neuromas, cystic astrocytomas of the cerebellum , colloid cysts of the third ventricle, congenital tumors such as dermoid cyst, and some of the granulomas.

30. For patients with malignant glioma , complete removal of the tumor and cure are not possible, but the rationale for resection includes relieving ICP , removing any necrotic tissue, and reducing the bulk of the tumor , which theoretically leaves behind fewer cells to become resistant to radiation or chemotherapy .

31. Stereotactic approaches involve use of a three-dimensional frame that allows very precise localization of the tumor; a stereotactic frame and multiple imaging studies (x-rays, CT scans) are used to localize the tumor and verify its position. Lasers or radiation can be delivered with stereotactic approaches. Radioisotopes such as iodine 131 can also be implanted directly into the tumor to deliver high doses of radiation to the tumor (brachytherapy) while minimizing effects on surrounding brain tissue.

32. The use of the gamma knife to perform radiosurgery allows deep , inaccessible tumors to be treated, often in a single session. Precise localization of the tumor is accomplished using the stereotactic approach and by minute measurements and precise positioning of the patient . Multiple narrow beams then deliver a very high dose of radiation.

33. Nursing Interventions COMPENSATING FOR SELF-CARE DEFICITS IMPROVING NUTRITION RELIEVING ANXIETY ENHANCING FAMILY PROCESSES Thanking you.