Evidence map›Paper›PMID 42184343›Full record

ArticleJMIR rehabilitation and assistive technologies2026

Smartphone-Based Grading and Rehabilitation in Patients With Facial Palsy Using Computer Vision: Prospective Validation Study.

Franz-Tassilo Müller-Graff, Fabian Essig, Maximilian U Friedrich, Kathrin Hoika, Stephan Hackenberg, Kristen Rak, Johannes Taeger

Abstract read
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Article in JMIR rehabilitation and assistive technologies, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Franz-Tassilo Müller-GraffDepartment of Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Wuerzburg, Josef-Schneider-Strasse 11, Wuerzburg, 97080, Germany, 49 093120121485.ORCID http://orcid.org/0000-0002-0566-9278
Fabian EssigDepartment of Neurology, University Hospital Wuerzburg, Wuerzburg, Germany.ORCID http://orcid.org/0000-0003-3928-9473
Maximilian U FriedrichDepartment of Neurology, University Hospital Ulm, Ulm, Germany.ORCID http://orcid.org/0000-0002-3695-1268
Kathrin HoikaDepartment of Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Wuerzburg, Josef-Schneider-Strasse 11, Wuerzburg, 97080, Germany, 49 093120121485.ORCID http://orcid.org/0009-0009-9539-0817
Stephan HackenbergDepartment of Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Wuerzburg, Josef-Schneider-Strasse 11, Wuerzburg, 97080, Germany, 49 093120121485.ORCID http://orcid.org/0000-0001-6995-1849
Kristen RakDepartment of Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Wuerzburg, Josef-Schneider-Strasse 11, Wuerzburg, 97080, Germany, 49 093120121485.ORCID http://orcid.org/0000-0003-2109-3536
Johannes TaegerDepartment of Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Wuerzburg, Josef-Schneider-Strasse 11, Wuerzburg, 97080, Germany, 49 093120121485.ORCID http://orcid.org/0000-0002-9018-6915

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background: Peripheral facial palsy causes significant functional and psychosocial impairments, requiring precise assessment and patient engagement for effective rehabilitation. However, conventional clinician-graded scales (eg, House-Brackmann Scale, Sunnybrook Facial Grading System, and Stennert Index) are subjective and prone to interobserver variability, limiting their reliability for tracking recovery. Smartphone-based computer vision solutions offer objective, standardized facial movement grading, and interactive home-based training to improve adherence and outcomes. Objective: This pilot study evaluated a novel iOS smartphone app (Apple Inc.) for facial palsy management. The app uses the iPhone TrueDepth 3D camera and on-device computer vision to compute a Digital Facial Index (DFI) for objective facial movement analysis, and provides guided neuromuscular facial exercises with real-time biofeedback. The study aimed to validate DFI against standard clinical grading scales and assess patient-reported outcomes and usability. Methods: A 4-week single-arm pilot included 21 patients with unilateral facial palsy. Participants used the app at home for daily facial exercises and periodic self-assessments with DFI. Clinicians, blinded to DFI, rated facial function from standardized video exams at baseline and 4 weeks using the House-Brackmann Scale, the Sunnybrook Facial Grading System, and the Stennert Index. DFI concurrent validity was evaluated via correlation with these clinician scores. Patient-reported outcomes included pre- and postintervention Facial Disability Index (FDI) physical and social scores, the System Usability Scale, and a poststudy user feedback questionnaire. Results: During the study period, strong correlations were observed between DFI and conventional clinical scores. FDI physical and social showed significant functional improvement. Mean System Usability Scale was 88.3 (SD 15.4), indicating excellent usability, and participants reported high satisfaction, preferring the app over traditional paper-based exercises. Conclusions: The app's DFI provided objective facial function grading that correlated well with standard clinical scales. Patients' FDI scores improved significantly over 4 weeks. High usability and patient preference support the app's feasibility for home-based rehabilitation. This digital approach is promising for facial palsy management, and controlled studies are needed to confirm efficacy and improve long-term engagement.

Indexed as

computer visionDigital Facial Indexfacial diagnosticsfacial neuromuscular retrainingfacial palsymHealthmobile healthsmartphone sensorstelerehabilitationtruedepth camerausability

Identifiers

PMID42184343
PMCPMC13200776

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.