Newswise — The symptoms can be so similar to a host of other conditions that patients are often told that their chronic headaches and muscle weakness are psychosomatic, or that the symptoms are "all in their head." Patients with syringomyelia and Chiari Type 1 often present with an intense, burning-type nerve pain and/or headaches, among other symptoms. Chiari is indeed in the head, but it is a physical condition, most often congenital in nature. According to the American Association of Neurological Surgeons (AANS), the prevalence in the general population is estimated at slightly less than one in 1000.

Some patients with Chiari experience symptoms similar to those of fibromyalgia and chronic fatigue syndrome, which are also challenging to diagnose and treat. "Chiari that goes undiagnosed for a lengthy time can lead to real psychological problems in some patients, making the condition even more problematic to treat," said Ghassan Bejjani, MD, AANS spokesperson and an expert on Chiari.

"In many cases, symptoms can be addressed individually through nonsurgical treatments. Some patients can cope with the symptoms without any major problems, while others are severely impacted by the condition," remarked Dr. Bejjani. Symptoms vary greatly depending on the type of Chiari and the individual case, but may include:

"¢Severe head and neck pain"¢An occipital headache felt at the base of the skull that is made worse by coughing, sneezing, or straining"¢Loss of pain and temperature sensation of the upper torso and arms (as a result of a syrinx)"¢Loss of muscle strength in the hands and arms (as a result of a syrinx)"¢Drop attacks " collapsing to the ground due to muscle weakness"¢Spasticity"¢Dizziness"¢Balance problems"¢Double or blurred vision"¢Hypersensitivity to bright lights

Chiari is considered a congenital condition, although acquired forms of the condition have been diagnosed. A German pathologist, Professor Hans Chiari, first described abnormalities of the brain at the junction of the skull with the spine in the 1890s. He categorized these in order of severity; types I, II, III, and IV. These malformations are closely related to syringomyelia.

When cerebrospinal fluid (CSF) forms a cavity or cyst within the spinal cord, it is known as syringomyelia. This is a chronic disorder involving the spinal cord developing, expanding or extending over time. As the fluid cavity expands, it can displace or injure the nerve fibers inside the spinal cord. A wide variety of symptoms can occur, depending upon the size and location of the syrinx. Loss of sensation and pain are two of the symptoms. Syringomyelia can arise from several causes. While Chiari is the leading cause, the direct link is not well understood.

Surgical treatment of Chiari depends on the type of malformation. The goal of surgery is to relieve or stop the progression of the syrinx and/or symptoms by decompressing nerve tissue and restoring normal CSF flow around and behind the cerebellum. Decompression provides more space for the brain stem, spinal cord, and descended cerebellar components.

A recent study on decompressive surgery for Chiari presented at the 2008 AANS Annual Meeting provided some evidence that surgery is effective in reducing the size of the syrinx, but that this reduction does not seem to correlate to pain relief. However, researchers believe that early syrinx reduction may minimize the long-term pain experienced by patients with syringomyelia.

"It is really key that patients with either of these conditions work closely with their neurosurgeons and other healthcare providers on pain management strategies, because while surgery may help, it does not always provide complete resolution of symptoms," concluded Dr. Bejjani.

For more information on Chiari, visit http://www.neurosurgerytoday.org/what/patient_e/chiari1.asp. This is just one of 60 in-depth neurosurgical topics available on the AANS public Web site at http://www.NeurosurgeryToday.org.

Founded in 1931 as the Harvey Cushing Society, the American Association of Neurological Surgeons (AANS) is a scientific and educational association with more than 7,400 members worldwide. The AANS is dedicated to advancing the specialty of neurological surgery in order to provide the highest quality of neurosurgical care to the public. All active members of the AANS are certified by the American Board of Neurological Surgery, the Royal College of Physicians and Surgeons (Neurosurgery) of Canada or the Mexican Council of Neurological Surgery, AC. Neurological surgery is the medical specialty concerned with the prevention, diagnosis, treatment and rehabilitation of disorders that affect the entire nervous system, including the spinal column, spinal cord, brain and peripheral nerves.