Quantitative Measurement Methods

Sensitive new quantitative methods could be used to detect small signs of increased tremor and impaired motor skills caused by exposure to certain metals, according to a thesis from the Sahlgrenska Academy, University of Gothenburg, Sweden. The methods studied in the thesis may also be used to follow up the treatment of neurological disorders.

“The aim was to investigate whether quantitative measurement methods, in other words sensitive computer-based methods, could be used to detect small changes in tremor or other motor functions resulting from exposure to low levels of neurotoxic metals,” says Gunilla Wastensson, doctoral student at the Sahlgrenska Academy.

The thesis looked at former welders exposed to manganese from welding fumes in Gothenburg shipyards. When tested for fine motor skills like manual dexterity and motor speed, the welders faired worse than other shipyard workers.

“We interpret this as a residual effect of manganese exposure from the welding fumes, even though they’d stopped welding 18 years ago on average,” says Wastensson.

A second study looked into whether quantitative measurement methods can be used to follow up the treatment of certain neurological disorders, such as essential tremor (ET). Some cases can be treated with deep brain stimulation (DBS) administered by specially trained staff..

ET patients treated with DBS were both examined by an experienced neurologist who estimated the degree of tremor on a scale of 0 to 4, and assessed using quantitative measurement methods. The effect of the stimulation was very prominent, and the quantitative measurement methods were slightly more sensitive at detecting changes, particularly where the tremor was less pronounced.

“The results show that quantitative measurement methods are more sensitive than clinical assessments. They can be used to detect small changes in tremor or other motor functions caused by neurotoxic metals,” says Wastensson.

She also believes that quantitative measurement methods could be used to complement clinical assessments when determining the impact of treatments for various neurological disorders.

Download the thesis