SKINOPATHY AI: Smartphone-Based Ophthalmic Screening and Longitudinal Tracking Using Lightweight Computer Vision
Authors: S. Kalaycioglu, C. Hong, M. Zhu, H. Xie
Organizations: Toronto Metropolitan University · York University · AIMechatroniX Inc. · DrRobot Inc · Skinopathy Inc. · Scarborough Health Network, Centenary Hospital, Scarborough, Ontario, Canada
Early ophthalmic screening in low-resource and remote settings is constrained by access to specialized equipment and trained practitioners. We present SKINOPATHY AI, a smartphone-first web application that delivers five complementary, explainable screening modules entirely through commodity mobile hardware: (1) redness quantification via LAB a* color-space normalization; (2) blink-rate estimation using MediaPipe FaceMesh Eye Aspect Ratio (EAR) with adaptive thresholding; (3) pupil light reflex characterization through Pupil-to-Iris Ratio (PIR) time-series analysis; (4) scleral color indexing foricterus and anemia proxies via LAB/HSV statistics; and (5) iris-landmark-calibrated lesion encroachment measurement with millimeter-scale estimates and longitudinal trend tracking. The system is implemented as a React/FastAPI stack with OpenCV and MediaPipe, MongoDB-backed session persistence, and PDF report generation. All algorithms are fully deterministic, privacy-preserving, and designed for non-diagnostic consumer triage. We detail system architecture, algorithm design, evaluation methodology, clinical context, and ethical boundaries of the platform. SKINOPATHY AI demonstrates that multi-signal ophthalmic screening is feasible on unmodified smartphones without cloud-based AI inference, providing a foundation for future clinically validated mobile ophthalmoscopy tools.
Figures & tables
Tier
Technology
Role
Frontend
React, Chart.js, MediaRecorder API, Axios
UI, consent, media capture, visualization
Backend
FastAPI, OpenCV, MediaPipe FaceMesh, ReportLab
Image/video processing, metrics, PDF export
Database
MongoDB (Motor async client), UUID keys
Session storage, result persistence, trend data
DevOps
Supervisor, Kubernetes ingress, .env variables
Process management, routing, configuration
Table 1: System Technology Stack by Tier
Figure 1: Schematic overview of SKINOPATHY AI three-tier architecture.
Binary mask; M(x,y)=1 if pixel belongs to region of interest
EM[⋅]
—
Spatial expectation over mask: (1/NM)∑(x,y):M(x,y)=1f(x,y)
p i
R2
Unnormalized pixel-space landmark coordinate (x i , y i )
Table 2: Unified Notation for All Module Algorithms
Figure 2: SKINOPATHY AI — Red-Eye Meter module. The user captures or uploads an eye photograph; the system computes a redness score (0–10) via LAB a* analysis and displays triage guidance. Illustrated output: 3.66/10 (mild, monitor). Camera device selection and live preview are provided to guide optimal capture. Screening only; not diagnostic.
Module
Primary Metric
Pilot Value
Target (Full Study)
Status
Redness
Spearman r s
0.86
> 0.80 vs. Efron grade
Pilot complete
Blink Rate
MAE (blinks/min)
2.1 ± 0.9
< 2.5 blinks/min MAE
In progress
Pupil Reflex
Latency error (ms)
42 ± 18 ms
< 50 ms vs. pupillometer
Pilot complete
Color Screen
Icterus AUC
0.79
> 0.80 vs. clinical grade
In progress
Lesion Track.
MAE (mm)
0.31 ± 0.12 mm
< 0.5 mm vs. slit-lamp
Ongoing
Table 3: Pilot Performance Summary by Module
Figure 3: SKINOPATHY AI — Blink Coach module. The user records a 10-second selfie video; MediaPipe FaceMesh and adaptive EAR thresholding detect blink events. Illustrated output: 17 blinks detected, rate = 102.05 blinks/min (elevated; re-recording with stable head position recommended). The module provides blink count, rate, and normative guidance (typical adult range: 15–20 blinks/min).
Figure 4: SKINOPATHY AI — Pupil Reflex Test module. The user records a 10-second video while briefly exposing the eye to a bright light source at approximately t = 3 s. MediaPipe FaceMesh with iris refinement tracks the Pupil-to-Iris Ratio (PIR) time-series. Key metrics extracted include PLR amplitude ( Δrel ), latency (L ms ), mean constriction velocity (v mean ), and a recording quality score Q. The module targets neurological screening signals; absent or markedly delayed constriction warrants clinical follow-up. This figure shows the baseline without the application of a bright light source.
Figure 5: SKINOPATHY AI — Pupil Reflex Test module (additional view). The user records a 10-second video while briefly exposing the eye to a bright light source at approximately t = 3 s. MediaPipe FaceMesh with iris refinement tracks the Pupil-to-Iris Ratio (PIR) time-series.
Figure 6: SKINOPATHY AI — Color Health Screen module. The user uploads or captures an eye photograph; the system computes the Yellow Index (icterus proxy from LAB b*) and Pallor Index (anemia proxy from LAB L* and a*) over a luminance-gated scleral mask. Gray-world white balance correction is applied before color analysis. Outputs include both indices on [0,1] with uncertainty bands and conservative triage messaging. Screening only; not diagnostic.
Figure 7: SKINOPATHY AI — Lesion Detection & Tracking module. MediaPipe FaceMesh iris landmarks calibrate the pixel-to-millimeter conversion factor using the population mean HVID (11.8 mm). A multi-space color filter (LAB + HSV) segments candidate lesion pixels within the near-limbus annular analysis band (0.65–0.98 ρiris ). Illustrated output: iris diameter assumed 11.8 mm; distance from limbus = 0 mm (no lesion detected). The OLS trend estimator flags progressive lesions when v^growth > 0.005 mm/day. Heuristic MVP; trained segmentation model planned for future release.
Appendix figures & tables2 assets
Supplementary material from the paper’s appendix.
Appendix
Method
Endpoint
Description
POST
/api/sessions
Create new session; accepts consent and intake JSON; returns session_id (UUID)
GET
/api/sessions
List all sessions for the current user context; returns array of session summaries
GET
/api/sessions/{id}
Retrieve full session document including all module results and intake data
GET
/api/sessions/{id}/report.pdf
Generate and download PDF report for session; includes all intake and results
Department of Ophthalmology, Emory University, Atlanta, Georgia, United States · Department of Biomedical Engineering, National University of Singapore, Singapore · Singapore Eye Research Institute, Singapore National Eye Centre, Singapore +5
Vishwakarma Institute Of Technology, Computer Engineering Department, Pune , India · Vishwakarma Institute Of Technology, Computer Science and Engineering (AI & ML ) Department, Pune , India