Automated video-based assessment of facial bradykinesia in de-novo Parkinson’s disease

Abstract

Even though hypomimia is a hallmark of Parkinson’s disease (PD), objective and easily interpretable tools to capture the disruption of spontaneous and deliberate facial movements are lacking. This study aimed to develop a fully automatic video-based hypomimia assessment tool and estimate the prevalence and characteristics of hypomimia in de-novo PD patients with relation to clinical and dopamine transporter imaging markers. For this cross-sectional study, video samples of spontaneous speech were collected from 91 de-novo, drug-naïve PD participants and 75 age and sex-matched healthy controls. Twelve facial markers covering areas of forehead, nose root, eyebrows, eyes, lateral canthal areas, cheeks, mouth, and jaw were used to quantitatively describe facial dynamics. All patients were evaluated using Movement Disorder Society-Unified PD Rating Scale and Dopamine Transporter Single-Photon Emission Computed Tomography. Newly developed automated facial analysis tool enabled high-accuracy discrimination between PD and controls with area under the curve of 0.87. The prevalence of hypomimia in de-novo PD cohort was 57%, mainly associated with dysfunction of mouth and jaw movements, and decreased variability in forehead and nose root wrinkles (p < 0.001). Strongest correlation was found between reduction of lower lip movements and nigro-putaminal dopaminergic loss (r = 0.32, p = 0.002) as well as limb bradykinesia/rigidity scores (r = −0.37 p < 0.001). Hypomimia represents a frequent, early marker of motor impairment in PD that can be robustly assessed via automatic video-based analysis. Our results support an association between striatal dopaminergic deficit and hypomimia in PD.

Computerized analysis of hypomimia and hypokinetic dysarthria for improved diagnosis of Parkinson's disease

“…These facts are confirmed by statements in the literature on PD [11] , [12] , [17] , [20] . The proposed model has clinical explainability and is also supported by literature [51] , [59] . What could be stated about the choice of the metrics is that the most informative among all created features were approximate entropy, variance, slope, and rsd.…”

“…The work in [51] created 12 markers based on 68 facial landmarks of two types: distances and areas. In the research, there were involved 91 de-novo and drug-naive patients and 79 HC with the limitation to people suffering from depression.…”

Does Black vs. White race affect practitioners’ appraisal of Parkinson’s disease?

“…Of added importance, hypomimia can be one of the first motor manifestations and is a distinctive clinical feature in patients with PD, presenting as many as 10 years before a clinical diagnosis of PD is determined 17 – 19 . Hypomimia is present in most patients with PD (approximately 92%; race not reported) 18 , 20 . Therefore, accurately identifying signs such as hypomimia early in the course of PD could facilitate a timely diagnosis for patients.…”

“…Bradykinesia is a key part of many diagnostic criteria and is requisite for diagnosing PD; thus, it is crucial for practitioners to accurately identify this sign in patients 15 , 16 . Further, hypomimia is one manifestation of bradykinesia 17 , 18 . Of added importance, hypomimia can be one of the first motor manifestations and is a distinctive clinical feature in patients with PD, presenting as many as 10 years before a clinical diagnosis of PD is determined 17 – 19 .…”

Multi-Modal Deep Learning Diagnosis of Parkinson’s Disease—A Systematic Review

“…4) Alterations in Facial Expressions -Hypomimia: In clinical practice, the evaluation of hypomimia symptoms remains subjective or is confined to the identification of a few landmarks that inadequately explain the disease's subtle manifestations [59]. A recent study [98] presented a novel digital biomarker, represented as a spatio-temporal convolutional representation that learns facial movement patterns to differentiate between Parkinson and control patients as seen in Table XI in the Appendix.…”