Hemispherectomy
| Hemispherectomy | |
|---|---|
| Intervention | |
| ICD-9-CM | 01.52 |
| MeSH | D038421 |
Hemispherectomy is a very rare surgical procedure where one cerebral hemisphere (half of the brain) is removed or disabled. This procedure is used to treat a variety of seizure disorders where the source of the epilepsy is localized to a broad area of a single hemisphere of the brain. It is solely reserved for extreme cases in which the seizures have not responded to medications and other less invasive surgeries.
Contents |
[edit] History and changes
Hemispherectomy was first tried on a dog in 1888 by Friedrich Goltz. The first such operation on humans was done by Walter Dandy in 1923 for glioblastoma multiforme. In the 1960s and early 1970s, hemispherectomy involved removing half of the brain, but this resulted in unacceptable complications and side effects in many cases, predominantly filling of excessive body fluids in the skull with subsequent pressure to the remaining brain (known as hydrocephalus). The procedure was revitalized in children in the 1980s by Dr. Ben Carson at The Johns Hopkins Hospital. In many centers, the functional hemispherectomy has largely replaced this procedure, in which the temporal lobe is removed; a procedure known as corpus callosotomy is performed; and the frontal and occipital lobes are disconnected from the rest of the brain; however the traditional "anatomic" hemispherectomy has remained a viable procedure, due to its superiority in preventing future seizures compared with functional hemispherectomy.
[edit] Results
All hemispherectomy patients suffer at least partial hemiplegia on the side of the body opposite the removed or disabled portion, and may suffer problems with their vision as well.
This procedure is almost exclusively performed in children because their brains generally display more neuroplasticity, allowing neurons from the remaining hemisphere to take over the tasks from the lost hemisphere. This likely occurs by strengthening neural connections which already exist on the unaffected side but which would have otherwise remained small in a normally functioning, uninjured brain.[1] One case, demonstrated by Smith & Sugar, 1975; A. Smith 1987, demonstrated that one patient with this procedure had completed college, attended graduate school and scored above average on intelligence tests. Studies have found no significant long-term effects on memory, personality, or humor after the procedure,[2] and minimal changes in cognitive function overall.[3] Generally, the greater the intellectual capacity of the patient prior to surgery, the greater the decline in function. Most patients end up with mild to severe mental retardation, which is usually already present before surgery. When resecting the left hemisphere, evidence indicates that some advanced language functions (e.g., higher order grammar) cannot be entirely assumed by the right side. The extent of advanced language loss is often dependent on the patient's age at the time of surgery.[4]
Although initially thought to be limited solely to children, a recent study in 2007 by Dr. Shearwood McClelland III and Dr. Robert E. Maxwell indicated the long-term efficacy of anatomic hemispherectomy in carefully selected adults, with seizure control sustainable over multiple decades.[5]
[edit] Traumatic hemispherectomy
There are cases where a person that received major trauma to one side of the brain, such as a gunshot wound, has required a hemispherectomy and survived. The most notable case is that of Ahad Israfil, who lost the right side of his cerebrum in 1987 in a gun-related work accident. He eventually regained most of his faculties, though he still required a wheelchair. It was noted that reconstructive surgery was difficult due to the gunshot shattering his skull, and he lived for the next 15 years with a large indentation on that side of his head.
[edit] Foundations
The Hemispherectomy Foundation was formed in 2008 to assist families with children undergoing this procedure.[6]
[edit] See also
[edit] References
- ^ R. Chen, L. G. Cohen and M. Hallett, Nervous system reorganization following injury. Neuroscience. 2002;111(4):761-73. PMID 12031403
- ^ Vining EP, Freeman JM, Pillas DJ, Uematsu S, Carson BS, Brandt J, Boatman D, Pulsifer MB, Zuckerberg A. Why would you remove half a brain? The outcome of 58 children after hemispherectomy-the Johns Hopkins experience: 1968 to 1996. Pediatrics. 1997 Aug;100(2 Pt 1):163-71. PMID 9240794
- ^ Pulsifer MB, Brandt J, Salorio CF, Vining EP, Carson BS, Freeman JM. The cognitive outcome of hemispherectomy in 71 children. Epilepsia. 2004 Mar;45(3):243-54. PMID 15009226
- ^ Bayard S, Lassonde M. Cognitive, Sensory and Motor Adjustment to Hemispherectomy. In Neuropsychology of Childhood Epilepsy, ed. Jambaqué I. 2001.
- ^ McClelland S 3rd, Maxwell RE. Hemispherectomy for intractable epilepsy in adults: the first reported series. Ann Neurol. 2007 Apr;61(4):372-6. PMID 17323346.
- ^ "The Community News". http://www.community-news.com/node/3302. Retrieved 2009-02-25.[dead link]
[edit] External links
- Johns Hopkins Children's Center research findings
- Hopkins Medical News article on the topic
- The Hemispherectomy Foundation
- The Deepest Cut by Christine Kenneally, The New Yorker
[edit] Further reading
- Antonio M. Battro (2001). Half a Brain is Enough : The Story of Nico. Cambridge University Press. ISBN 0521783070. (ISBN 0-521-78307-0)
- Christine Kenneally (July 3, 2006). "The Deepest Cut". The New Yorker: 36–42.
- Charles Q. Choi (March 2008). "Do You Need Only Half Your Brain?". Scientific American 298 (3): 104. doi:10.1038/scientificamerican0308-104.
|
|||||||||||||||||||||||||||||||||||||||||||||||||
