P.R.I.S.M. Tx Design

Surgical target & flap planning — reasoning engine
LASIK / PRK ablation target · flap · optical zone · op-plan
Companion to PRISM
↗ Pre-Op Screening (IQ) ↗ Monovision Planner (Mono) ↗ Lens (IOL) ↗ Financials
Build v0.12. This is a first pass covering the rules specified so far. Zones, flap thickness/diameter and MMC follow the practice protocol (see References under the plan). Still placeholders pending your protocol, marked PLACEHOLDER and adjustable under Criteria: the myopia tier reduction schedule beyond −6 D and the surgical monovision near offset. Opening this module from PRISM IQ pre-fills the refraction, K's, surgical metrics, planned flap and screening context via the link; every field stays editable.

Patient & Procedure

Intake
Monovision Planning
Intended Target

Emmetropia is the starting point for every eye. Pick the residual you intend; the plan applies the high-myopia and inter-eye logic on top of it. Age is shown as advice only — it no longer sets the target.

Refraction Sources

MRx · Auto · Cyclo · iDesign — manifest entered in minus cyl
Right Eye · OD
Wearing
Auto
MRx
Cyclo
iDesign
Keratometry & Axial (from IQ)
Surgical Metrics (from IQ)
Left Eye · OS
Wearing
Auto
MRx
Cyclo
iDesign
Keratometry & Axial (from IQ)
Surgical Metrics (from IQ)

Reasoning Engine

Normalization · cross-check · net target
Right Eye · OD
Left Eye · OS

Treatment Plan

Non-dominant computed first, dominant second
Inter-eye axial/K adjustment — shifts the dominant eye's target by a % of the signed axial-length-derived diopter difference between the eyes. Off by default; toggle on to compare.
CL trial override — when a successful contact lens trial target is on file and the patient is at or above the age floor, plan to the trial result instead of emmetropia (only while the intended target is left at emmetropia).
Enter age, dominant eye, and at least MRx for both eyes to generate a treatment plan.
References — MMC, treatment zones, flap
  1. Thornton I, Puri A, Xu M, Krueger RR. Low-dose mitomycin C as a prophylaxis for corneal haze in myopic surface ablation. Am J Ophthalmol 2007;144:673–681 — and Thornton I, Xu M, Krueger RR. Comparison of standard (0.02%) and low dose (0.002%) mitomycin C in the prevention of corneal haze following surface ablation for myopia. J Refract Surg 2008;24:S68–S76. Standard 0.02% outperformed low dose for myopia ≥ −6.00 D / ablation ≥ 75 µm; 30 s vs 2 min exposure made no difference — basis for the 6.00 D trigger and the 0.02% concentration.
  2. Virasch VV, Majmudar PA, Epstein RJ, Vaidya NS, Dennis RF. Reduced application time for prophylactic mitomycin C in photorefractive keratectomy. Ophthalmology 2010;117:885–889. 12 s was equivalent to 2 min for haze prophylaxis — basis for the 12 s application.
  3. Majmudar PA, et al. Topical mitomycin-C for subepithelial fibrosis after refractive corneal surgery. Ophthalmology 2000;107:89–94. 2-minute 0.02% application is the therapeutic dose for established haze, not the prophylactic one.
  4. Talamo JH, et al. Modulation of corneal wound healing after excimer laser keratomileusis using topical mitomycin C and steroids. Arch Ophthalmol 1991;109:1141–1146. Original demonstration of MMC suppressing subepithelial fibrosis after ablation.
  5. Prophylaxis is not recommended for every PRK; recognized exceptions below the diopter trigger are high-cylinder (bow-tie) ablations, retreatment over prior corneal surgery, and prior haze (Epstein, Majmudar — Cataract & Refractive Surgery Today, 2007 & 2023).
  6. Treatment zones (6.5 mm large zone; 6.5 OZ blended to 8.0 mm, blend available only at ≥ 1.00 D of myopic correction; 9.0 mm hyperopic / mixed) and flap diameters (8.5 mm myopic, 9.0 mm to cover a 9.0 mm zone) are the practice's VISX / femtosecond protocol, entered by the surgeon — not literature-derived thresholds.
⚕ Planning aid — surgeon-verified before use. This is a foundational build; several thresholds are placeholders pending protocol confirmation (see build note above). All targets, flap parameters, and warnings must be independently verified by the operating surgeon before the printed op-plan is used for the day-of-surgery timeout. Nothing here replaces clinical judgment or standard timeout/verification procedures.