At first glance, the idea to examine the brain by ultrasound waves appears more than risky. Because this organ is well protected against ultrasound wave penetration by the scull cap. However, a small "window" at the temple proves to be the ideal gate for entry. From here the so-called brain parenchymsonography (transcranial sonography – TCS) penetrates the Substantia nigra. The clou: In more than 90 percent of all cases, a heightened regum flection of the ultrasound waves is observed in the Substantia nigra. The reason for the existence of this hyperechogenic zone is a high iron content in the damaged brain areas. Obviously, the iron accumulates there during the progression of the disease – this phenomenon benefits the TCS.
"When the first TCS was made on a Parkinson patient, nobody expected to see anything special", recalls Assistant Professor Daniela Berg of the Hertie-Institute for clinical brain research at Tuebingen/Germany. In the meantime, the method emerges as a potential break-through in Parkinson diagnosis.
The advantage is – gaining time
Because, compared to other diagnostic methods, the tremendous advantage is the massive gain of time for the patient. Of all things, the TCS eliminates that particular perfidy of the disease, which turns out to be the fate of every patient affected: For a long time, the neuronal loss does not cause any discomfort or troubles. By the time, the first symptoms show, such as the typical trembling hands, the brain is already heavily damaged. At that time, about two thirds of the cells producing Dopamine, the messenger responsible for quiet, steady movements, are irrevocably destroyed. In those cases, the production of Dopamine in the Substantia nigra is reduced to less than 20%. Because the Parkinson disease is invisible on CT and MRI, even in its latest stage, neurologists did not have a chance to diagnose the disease visually prior to the massive regression of Dopamine production.
Exactly this is now about to change. According to Berg, serious indications show that TCS make very early changes identifiable: "Should this assumption be confirmed, an easy to use, free of side effects and reasonable method will be available for the early- and pre-clinic diagnosis of the Parkinson disease for the very first time."
The Deutsche Gesellschaft für Ultraschall in der Medizin (DEGUM), the German Association for Ultrasound in Medicine, shares this evaluation. According to DEGUM, current tests show, that TCS "for the first time potentiate an early diagnosis of this appraxia". In the meantime, 6 centers in Germany count on this method: university hospitals at Rostock, Homburg/Saar, Tuebingen, Goettingen, Dresden and Magdeburg. Researchers in Magdeburg even see the TCS as a tool for fundamental research, if the method is used in combination with MRI. By involving the 7-Tesla MRI of the university hospital, the researchers at Magdeburg are aiming at the elementary genesis of the disease.
New ways to go for pharmaceutical researchers
Next to the fundamental-, the active ingredient research should benefit from using TCS. Because up to now, the lack of opportunity to detect patients at an early stage of the disease, blocked the way to develop active ingredients stopping the nemesis of Dopamine production right from its start. TCS finally opens new doors for pharmaceutical researchers in this field. For example in clinical studies, active agents could be tested, which – provided before the first symptoms occur – abide the body's production of Dopamine. For 270,000 Parkinson patients in this country a completely new perspective – with an according medication a life free of any disorders – the ideal case.