Manifestation and Diagnosis of Pilocytic Astrocytoma of the Brain

摘要

Astrocytoma is a tumor in the central nervous system that grows from astro cytes, a type of glial cells.1 Most astrocytomas are benign and have a cure rate of more than 90%. The 4 grades of astrocytoma are based on how likely the tumor will spread and become malignant. Most astrocytomas in children are low grade; in adults, most are high grade. Symptoms of astrocytoma vary according to the tumor size and its location in the central nervous system.2 According to the National Organization for Rare Disorders, if the patient experiences nausea, vomiting, impaired ability to coordinate voluntary movements, and wryneck (painful twisting and tilting of the neck), the tumor most likely is in the brainstem. If symptoms include optic disc swelling, involuntary eye movements, or paralysis of cranial nerves VI and VII, the tumor likely is in the ocular area. Symptoms in the optic nerve pathway include loss of vision, atrophy of optic nerve, papilledema (swelling of optic nerve due to increased pressure), nystagmus (repetitive, uncontrolled eye movements), and protruding of the eyeball. Symptoms in the hypothalamic region present as weight gain or loss, premature or delayed puberty, abnormal thinness, irritability, and eye abnormalities. The most common symptom of brain tumors is increased pressure in the brain, usually caused by blocked cerebrospinal fluid flow. Signs and symptoms not connected to a specific area include seizures, problems with vision, changes in behavior or mood, and weakness in the arms and legs.