About HeadachesWhat hurts when you have a headache? The bones of the skull and tissues of the brain itself never hurt, because they lack pain-sensitive nerve fibers. Several areas of the head can hurt, including a network of nerves which extends over the scalp and certain nerves in the face, mouth, and throat. Also sensitive to pain, because they contain delicate nerve fibers, are the muscles of the head and blood vessels found along the surface and at the base of the brain. The ends of these pain-sensitive nerves, called nociceptors, can be stimulated by stress, muscular tension, dilated blood vessels, and other triggers of headache. Once stimulated, a nociceptor sends a message up the length of the nerve fiber to the nerve cells in the brain, signaling that a part of the body hurts. The message is determined by the location of the nociceptor. A person who suddenly realizes "My toe hurts," is responding to nociceptors in the foot that have been stimulated by the stubbing of a toe. A number of chemicals help transmit pain-related information to the brain. Some of these chemicals are natural painkilling proteins called endorphins, Greek for "the morphine within." One theory suggests that people who suffer from severe headache and other types of chronic pain have lower levels of endorphins than people who are generally pain free. What Tests Are Used to Diagnose Headache? Diagnosing a headache is like playing Twenty Questions. Experts agree that a detailed question-and-answer session with a patient can often produce enough information for a diagnosis. Many types of headaches have clear-cut symptoms which fall into an easily recognizable pattern. Patients may be asked: How often do you have headaches? Where is the pain? How long do the headaches last? When did you first develop headaches? The patient's sleep habits and family and work situations may also be probed. Most physicians will also obtain a full medical history from the patient, inquiring about past head trauma or surgery, eye strain, sinus problems, dental problems, difficulties with opening and closing of the jaw, and the use of medications. This may be enough to suggest strongly that the patient has migraine or cluster headaches. A complete and careful physical and neurological examination will exclude many possibilities and the suspicion of aneurysm, meningitis, or certain brain tumors. A blood test may be ordered to screen for thyroid disease, anemia, or infections which might cause a headache. A test called an electroencephalogram (EEG) may be given to measure brain activity. EEG's can indicate a malfunction in the brain, but they cannot usually pinpoint a problem that might be causing a headache. A physician may suggest that a patient with unusual headaches undergo a computed tomographic (CT) scan and/or a magnetic resonance imaging (MRI) scan. The scans enable the physician to distinguish, for example, between a bleeding blood vessel in the brain and a brain tumor, and are important diagnostic tools in cases of headache associated with brain lesions or other serious disease. CT scans produce X-ray images of the brain that show structures or variations in the density of different types of tissue. MRI scans use magnetic fields and radio waves to produce an image that provides information about the structure and biochemistry of the brain. If an aneurysm-an abnormal ballooning of a blood vessel-is suspected, a physician may order a CT scan to examine for blood and then an angiogram. In this test, a special fluid which can be seen on an X-ray is injected into the patient and carried in the bloodstream to the brain to reveal any abnormalities in the blood vessels there. A physician analyzes the results of all these diagnostic tests along with a patient's medical history and examination in order to arrive at a diagnosis. Headaches are diagnosed as * Vascular Vascular headaches - a group that includes the well-known migraine - are so named because they are thought to involve abnormal function of the brain's blood vessels or vascular system. Muscle contraction headaches appear to involve the tightening or tensing of facial and neck muscles. Traction and inflammatory headaches are symptoms of other disorders, ranging from stroke to sinus infection. Some people have more than one type of headache. |