Electroencephalograms (EEG): Catching a Brain Wave

Written by Gary Cordingley


In this era of rapidly developing technology for medical imaging, one test that might seem downright old-fashioned is an electroencephalogram (EEG) or brain-wave test. But by its very nature,repparttar EEG test will continue to occupy a valuable niche in medical diagnosis that brain-imaging tests—like CT scans and MRI scans—will never fill.

Rather than making pictures ofrepparttar 142770 brain's anatomy, EEGs evaluaterepparttar 142771 brain's physiology. So while imaging tests won't replace electroencephalograms, EEGs won't replace imaging tests, either. The testing methods look atrepparttar 142772 brain from completely different points of view, each valuable in its own way.

Broken into its parts,repparttar 142773 term electroencephalogram means "electrical brain recording."

Hans Berger, a German scientist, gotrepparttar 142774 ball rolling in 1924 withrepparttar 142775 first recordings of human brain-waves. Since then,repparttar 142776 basic principles of recording EEGs have remainedrepparttar 142777 same, butrepparttar 142778 electronics have gotten better—and smaller. In an EEG recording, tiny voltage-fluctuations fromrepparttar 142779 brain are picked up by a standard array of metal disks attached torepparttar 142780 scalp and are then amplified electronically in order to create a permanent recording.

If you are old enough, you might rememberrepparttar 142781 1960s fascination with alpha waves which people tried to enhance via biofeedback devices. Alpha waves are rhythmic brain-signals oscillating between 8 and 13 times per second that can be measured fromrepparttar 142782 back ofrepparttar 142783 head during quiet wakefulness.

Additional voltage-rhythms encountered during clinical recordings include theta and delta waves that oscillate more slowly than alpha waves, and beta waves that oscillate more rapidly. All four rhythms can be seen in normal states of alertness, drowsiness or sleep, and should berepparttar 142784 same on both sides ofrepparttar 142785 brain.

The premier use of EEGs is to evaluate people with known or suspected epilepsy (seizure disorders). Seizures are highly electrical events inrepparttar 142786 brain that cause temporary alterations inrepparttar 142787 patient's consciousness, perceptions or behavior.

In healthy circumstances,repparttar 142788 brain's approximately 20 billion brain cells perpetually signal each other via electrical impulses. Collectively, these impulses traveling among networks of brain-cells arerepparttar 142789 means by whichrepparttar 142790 brain performs its functions—like perceiving, pondering, remembering, calculating and deciding. A poetic scientist describedrepparttar 142791 brain and its normal functioning as "an enchanted loom where millions of flashing shuttles weave a dissolving pattern, always a meaningful pattern though never an abiding one; a shifting harmony of subpatterns."

But in epileptic attacks, salvo upon salvo of excessive discharges overwhelmrepparttar 142792 brain's circuits and disrupt their normal functions. Suddenly,repparttar 142793 enchanted loom's patterns are no longer meaningful or harmonious.

A seizure-in-progress is readily detected by an EEG recording. However, most patients under evaluation for seizures don't obligerepparttar 142794 doctor by having an attack during a typical 30-90 minute recording session. Fortunately, for purposes of diagnosis this is not usually necessary. Tell-tale changes in brain-waves are often present duringrepparttar 142795 periods between attacks—whilerepparttar 142796 patient feels normal—that can reveal a tendency to epilepsy and even identify specific sub-types.

Zometa and Aredia Warning. Victim Compensation

Written by Jt


Zometa, Aredia,Fosamax Side Effects Warning. Victim Compensation

Fosamax (generic name Alendronate) Zometa and Aredia are types of drugs known as bisphosphonates. Recently a link has been found between bisphosphonates and a serious bone disease called osteonecrosis ofrepparttar jaw (ONJ). This important discovery clearly shows that Fosamax and Zometa side effects may include osteonecrosis ofrepparttar 142739 jaw (also known as Dead Jaw.)

The discovery published inrepparttar 142740 Journal of Oral and Maxillofacial Surgeons prompted bothrepparttar 142741 US Food and Drug Administration FDA and Novartisrepparttar 142742 manufacturer of bisphosphonates used in cancer chemotherapy to issue a warning to health care professionals on September 24 2004. The warning letter contained information about bisphosphonates andrepparttar 142743 risks of osteonecrosis inrepparttar 142744 jaw Bisphosphonates are commonly used in tablet form such as Fosamax Alendronate Sodium to prevent and treat osteoporosis in postmenopausal women. Stronger forms of bisphosphonates are commonly used inrepparttar 142745 management of advanced cancers that have metastasized torepparttar 142746 bone whererepparttar 142747 disease often causes bone pain and possibly even fractures.

Several cancers can involve or metastasize torepparttar 142748 bone including lung cancer breast cancer prostate cancer multiple myeloma and others. When bisphosphonates are given in cancer chemotherapyrepparttar 142749 drugs are given intravenously and usually for longer periods of time.

Osteonecrosis ofrepparttar 142750 jaw. ONJ is a condition in whichrepparttar 142751 bone tissue inrepparttar 142752 jaw fails to heal after minor trauma such as a tooth extraction causingrepparttar 142753 bone to be exposed. The exposure can eventually lead to infection and fracture and may require longterm antibiotic therapy or surgery to removerepparttar 142754 dying bone tissue.

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