# Development and Clinical Validation of the DMEK Risk and Outcome Prediction (DROP) Score: A Dynamic Temporal Machine Learning Framework

## TL;DR

The DROP Score is a new machine learning model that predicts outcomes for DMEK surgery by combining patient, donor, surgical, and center data.

## Contribution

The DROP Score introduces a dynamic, multi-domain risk prediction framework validated with clinical and imaging data for DMEK outcomes.

## Key findings

- High-risk patients had worse visual acuity and higher poor prognosis rates at 12 months.
- Diabetes mellitus was the strongest prognostic factor for DMEK outcomes.
- Tissue classification accuracy using IVCM imaging reached 96.2%.

## Abstract

Background/Objectives: To develop and validate the DMEK Risk and Outcome Prediction (DROP) Score—a benchmarking model integrating patient, donor, surgical, and center-specific parameters for individualized risk assessment following DMEK. Methods: The DROP Score comprises four subscores, namely the Patient Risk Profile (PRP), Donor Tissue Quality (DTQ), Surgical Complexity Index (SCI), and Center Performance Factor (CPF), with literature-derived weights (α = 0.40, β = 0.25, γ = 0.20, δ = 0.15) validated by sensitivity analysis (K = 0.82–0.91). Clinical validation included 76 DMEK eyes and 89 controls (2019–2023). Machine learning models utilized EfficientNetV2B3 transfer learning with Random Forest classifiers and patient-level data partitioning. IVCM imaging comprised 6200 images. Results: The mean DROP Score was 39.35 ± 7.61 (Moderate: 92.1%; High: 7.9%). High-risk patients showed worse 12-month BCVA (0.50 vs. 0.31 logMAR) and higher poor prognosis rates (50.0% vs. 34.3%). The DROP Score showed significant correlations with BCVA (r = 0.305, p = 0.007) and ECD (r = −0.352, p = 0.002). Tissue classification accuracy reached 96.2%. Diabetes mellitus emerged as the strongest prognostic factor (OR: 4.34, p = 0.012), followed by hypertension (OR: 2.65, p = 0.078). Conclusions: The DROP Score provides transparent, individualized DMEK risk assessment. Diabetes mellitus and hypertension emerged as dominant systemic prognostic factors, while rebubbling showed no adverse impact on long-term outcomes. Complete four-domain validation requires ongoing prospective data collection.