disease( but in an anatomical pattern that causes CBS) and another 20 % have the same brain abnormalities that underlie PSP. A few are caused by the abnormalities underlying dementia with Lewy bodies or other rare conditions.
Because it is very difficult during life to tell if someone with corticobasal syndrome in fact has corticobasal degeneration as their underlying brain disorder, neurologists are increasingly using the term“ CBS” in reference to living patients and“ CBD” only in reference to autopsy-proven corticobasal degeneration.
Regardless of the term used or the specific set of neurological signs and symptoms, treatment and care should be tailored to meet the unique needs and preferences of the individual.
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How is CBD diagnosed? Accurately diagnosing CBD can be difficult or sometimes impossible for even the most experienced neurologist. There are no generally accepted blood tests or spinal fluid tests for CBD. To diagnose CBD, a neurologist will gather a person’ s medical history, including neurological symptoms, and perform a physical examination. Brain scans, such as MRI, CT and PET, can show an asymmetric loss of bulk or function in certain parts of the brain, usually asymmetrically, corresponding to the asymmetry of the outward signs and symptoms. The brain imaging is most useful in ruling out other conditions, such as stroke or multiple sclerosis.
How is CBD treated? At this time, we have no medication to cure CBD or to slow its progression. Doctors will usually attempt a trial of carbidopa-levodopa, which is the most common medication used to manage Parkinson’ s disease. Unfortunately, the response to this medication is typically not nearly as dramatic or long-lasting as it is in Parkinson’ s disease. Still, for some people, it can help to manage slowness and stiffness of CBD. If it is not helpful for someone’ s symptoms at all, or if the benefit is outweighed by side effects, which can include sleepiness and nausea, the doctor may recommend decreasing the medication over a week or two and then stopping it.
Amantadine is an antiparkinsonian drug that can sometimes help with the freezing of gait in CBD. The dosage of amantadine should not exceed 200-300mg per day because at higher doses, it can cause confusion, constipation and urinary retention. Other drugs often used for Parkinson’ s disease, such as dopamine agonists, COMT inhibitors and MAO-B inhibitors, do not help CBD and can cause a number of side effects. Additionally, the various extendedrelease formulations of carbidopa-levodopa do not help more than the regular formulation. However, the orally dissolvable form of carbidopa-levodopa may be easier for people with CBD who have difficulty swallowing pills.
The sometimes-painful muscle spasms that can be experienced by some people with CBD may respond to muscle relaxant drugs, such as cyclobenzaprine, baclofen and tizanidine. A medication for seizures called levitiracetam can also help this symptom and may be better