Validity of spiral analysis in early Parkinson's disease.
Spiral analysis is an objective, easy to administer noninvasive test that has been proposed to measure motor dysfunction in Parkinson disease (PD). We compared overall Unified Parkinson Disease Rating Scale Part III scores to selected indices derived from spiral analysis in seventy-four patients with early PD (mean duration of disease 2.4 +/- 1.7 years, mean age 61.5 +/- 9.7 years). Of the spiral indices, degree of severity, first order zero crossing, second order smoothness, and mean speed were best correlated with total motor Unified Parkinson's Disease Rating Scale (UPDRS) score (all P < 0.01), and these indices showed a gradient across worsening tertiles of UPDRS (P < 0.05). Spiral indices also correlated with UPDRS ratings for the worst side and worst arm scores as well. The domains of bradykinesia, rigidity, and action tremor were correlated with first order crossing, second order smoothness, and mean speed, where as rest tremor was most highly correlated with degree of severity. This suggests that the spiral analysis may supplement motor assessment in PD, although further analysis of spiral metrics, a larger sample and longitudinal data should be evaluated.
Saunders-Pullman
Rachel
R
Department of Neurology, Beth Israel Medical Center, New York, New York 10003, USA. rsaunder@bethisraelny.org
Derby
Carol
C
Stanley
Kaili
K
Floyd
Alicia
A
Bressman
Susan
S
Lipton
Richard B
RB
Deligtisch
Amanda
A
Severt
Lawrence
L
Yu
Qiping
Q
Kurtis
Mónica
M
Pullman
Seth L
SL
D000367:Age Factors; D001696:Biomechanical Phenomena / Q000379:methods; D003937:Diagnosis, Differential; D005260:Female; D006236:Handwriting; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000175:diagnosis*; D011596:Psychomotor Disorders / Q000175:diagnosis* / Q000209:etiology*; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D014202:Tremor / Q000175:diagnosis* / Q000209:etiology*