14 Analysis of spiral drawings as a means of exploring differences between functional and essential tremor: an ink and paper approach. Issue 8 (13th July 2017)

• Record Type: Journal Article
• Authors: Moughal, Saad; Coebergh, Jan Adriaan
• Is Part Of: Journal of neurology, neurosurgery and psychiatry. Volume 88:Issue 8(2017)
• Page Start: A18
• Page End: A18
• Publication Date: 2017-07-13
• Subjects: Neurology -- Periodicals; Nervous system -- Surgery -- Periodicals; Psychiatry -- Periodicals; 616.8
• DOI: 10.1136/jnnp-2017-BNPA.38
• Languages: English
• ISSNs: 0022-3050

Abstract

Abstract : Objective: To compare spiral drawings between essential tremor (ET) and functional tremor (FT); exploring spiral size, axis, density and tremor severity score for parameters to potentially distinguish ET from FT. Method: Spiral drawing data of 29 patients with either ET or FT were acquired from ASPH using the NHs patient database and patient notes. Using a ruler spiral size was represented as the horizontal diameter, and it was also measured to 3-loops (3-turn diameter/3TD). Spiral density was determined using total loop number and the horizontal diameter of each spiral. Tremor severity score was determined using a validated tremor scale (Bain). The spirals were also rated for the presence of single or multiple axes. An independent t-test was used to compare tremor severity, 3TD and size and a Mann-Whitney test was used to compare spiral density between both groups. Results: Spirals drawn by ET patients had significantly higher tremor severity scores than FT patients (4.18 vs 2.82 p=0.03). Spiralaxis is significantly affected by tremor type (p=0.03); there was a significantly greater proportion of patients in the ET group that demonstrate a single axis on spirography compared to those in the FT group (57% vs 14.3%; p=0.02). In two patients with FT and ET there were variable degrees of change in tremor severity over time, with the change in severity in FT being greater than in ET. Conclusion: ET and FT can be distinguished by tremor severity and the presence of a single vs multiple axis on analysis of handwritten spiral drawings.