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AMD Severity Scale Astigmatism Assistant Barrett / SRK-T Sim Diabetic Retinopathy Risk Glaucoma Progression Glaucoma Risk (OHTS)Graves CAS HFA MD to VFI Converter IOP Correction (CCT)LogMAR <-> Snellen MRD Assessment ROP Risk (G-ROP)SPEED Score (Dry Eye)SUN Uveitis Grading Vertex Distance

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Clinical Notice:OpiCalc is not a substitute for professional clinical judgment. Always verify dosages and guidelines.

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Recent Journal Updates

DiabetologiaJun 8, 2026

Genetics of MASLD: a diabetes perspective

Clinical Context

We think this might be relevant to the clinical guidance for MRD-1 / MRD-2 Assessment.

Intensive Care MedicineJun 8, 2026

Patient blood management in general intensive care patients

Clinical Context

We think this might be relevant to the clinical guidance for MRD-1 / MRD-2 Assessment.

DiabetologiaJun 6, 2026

Time-restricted eating versus dietetic guidance on glycaemic outcomes in adults at risk of type 2 diabetes: a non-inferiority randomised clinical trial

Clinical Context

We think this might be relevant to the clinical guidance for MRD-1 / MRD-2 Assessment.

MRD Assessment

MRD-1 (Upper Lid)

mm

MRD-2 (Lower Lid)

mm

Guidelines & Evidence

Verified

Last Review: 2026

How it Works

Definitions

MRD-1: Distance from the upper eyelid margin to the corneal light reflex (Normal: 4-5 mm)

MRD-2: Distance from the corneal light reflex to the lower eyelid margin (Normal: 5 mm)

Palpebral Fissure (PF): MRD-1 + MRD-2

Clinical Interpretation

MRD-1 < 4mm typically defines ptosis. Low MRD-1 with a high MRD-2 may suggest eyelid retraction (e.g., in Graves disease).

Last Comprehensive Review: 2026

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LogMAR <-> Snellen

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