macular function tests ophthalmology Amsler grid photostress ERG comprehensive

macular dystrophy types Stargardt Best vitelliform Sorsby pattern dystrophy classification management 2024

macular function tests potential acuity meter laser interferometry two-point discrimination entoptic phenomenon ophthalmology

https://www.ncbi.nlm.nih.gov/books/NBK587444/

Amsler grid macular function test metamorphopsia

Stargardt disease fundus fluorescein angiography silent choroid

Best vitelliform macular dystrophy egg yolk stages

mkdir -p /home/daytona/workspace/macular-ppt && ls /home/daytona/workspace/macul…

~/macular-ppt/build.js

const pptxgen = require("pptxgenjs");

const pres = new pptxgen();
pres.layout = "LAYOUT_16x9";
pres.title = "Macular Function Tests & Macular Dystrophy";
pres.author = "Ophthalmology Residency Education";

// ─── COLOR PALETTE ───────────────────────────────────────────────
const C = {
  navy:    "0A2342",   // dominant dark background
  teal:    "1B7F79",   // section accent
  gold:    "F4A623",   // highlight / accent
  white:   "FFFFFF",
  offWhite:"E8F0F7",
  slate:   "3A506B",
  light:   "BDD5EA",
  red:     "D94F3D",
  green:   "2E8B57",
  gray:    "8899AA",
};

// ─── HELPERS ─────────────────────────────────────────────────────
function titleSlide(slide, title, subtitle) {
  // Full-bleed navy background
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.navy} });
  // Gold accent bar
  slide.addShape(pres.ShapeType.rect, { x:0, y:3.8, w:"100%", h:0.06, fill:{color:C.gold} });
  // Decorative side element
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.25, h:"100%", fill:{color:C.teal} });
  slide.addText(title, {
    x:0.5, y:1.5, w:9, h:1.8,
    fontSize:40, bold:true, color:C.white, fontFace:"Calibri",
    align:"center", valign:"middle"
  });
  if (subtitle) {
    slide.addText(subtitle, {
      x:0.5, y:3.5, w:9, h:0.8,
      fontSize:18, color:C.light, fontFace:"Calibri",
      align:"center", italic:true
    });
  }
  slide.addText("Ophthalmology Residency Education  |  2026", {
    x:0.5, y:5.1, w:9, h:0.4,
    fontSize:12, color:C.gray, fontFace:"Calibri", align:"center"
  });
}

function sectionHeader(slide, sectionNum, sectionTitle, sectionSub) {
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.teal} });
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:0.12, fill:{color:C.gold} });
  slide.addShape(pres.ShapeType.rect, { x:0, y:5.5, w:"100%", h:0.125, fill:{color:C.gold} });
  slide.addText(`SECTION ${sectionNum}`, {
    x:0.5, y:1.2, w:9, h:0.5,
    fontSize:16, color:C.gold, bold:true, charSpacing:5,
    fontFace:"Calibri", align:"center"
  });
  slide.addText(sectionTitle, {
    x:0.5, y:1.9, w:9, h:1.5,
    fontSize:38, bold:true, color:C.white, fontFace:"Calibri",
    align:"center", valign:"middle"
  });
  if (sectionSub) {
    slide.addText(sectionSub, {
      x:0.5, y:3.6, w:9, h:0.8,
      fontSize:18, color:C.light, fontFace:"Calibri",
      align:"center"
    });
  }
}

function contentSlide(slide, heading, bullets, opts={}) {
  // Background
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.offWhite} });
  // Left accent bar
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.18, h:"100%", fill:{color:C.navy} });
  // Header strip
  slide.addShape(pres.ShapeType.rect, { x:0.18, y:0, w:9.82, h:1.0, fill:{color:C.navy} });
  slide.addText(heading, {
    x:0.35, y:0, w:9.5, h:1.0,
    fontSize:22, bold:true, color:C.white, fontFace:"Calibri",
    valign:"middle", margin:0
  });
  // Gold accent underline
  slide.addShape(pres.ShapeType.rect, { x:0.18, y:1.0, w:9.82, h:0.05, fill:{color:C.gold} });

  const items = bullets.map((b, i) => {
    if (typeof b === "string") {
      return { text: b, options: { bullet:{type:"bullet"}, color:C.navy, fontSize:opts.fontSize||17, fontFace:"Calibri", paraSpaceAfter:6, breakLine: i < bullets.length-1 } };
    } else {
      // {text, sub:true, bold:true, color}
      return { text: b.text, options: { bullet: b.sub ? {indent:30} : {type:"bullet"}, color: b.color||C.slate, fontSize: b.sub ? (opts.fontSize||17)-2 : (opts.fontSize||17), bold: b.bold||false, italic: b.italic||false, fontFace:"Calibri", paraSpaceAfter: b.sub?3:6, breakLine: i < bullets.length-1 } };
    }
  });

  slide.addText(items, {
    x:0.4, y:1.1, w:9.4, h:4.4,
    valign:"top", margin:[8,4,4,10]
  });
}

function twoColSlide(slide, heading, leftHead, leftBullets, rightHead, rightBullets) {
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.offWhite} });
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.18, h:"100%", fill:{color:C.navy} });
  slide.addShape(pres.ShapeType.rect, { x:0.18, y:0, w:9.82, h:0.9, fill:{color:C.navy} });
  slide.addText(heading, {
    x:0.35, y:0, w:9.5, h:0.9,
    fontSize:22, bold:true, color:C.white, fontFace:"Calibri", valign:"middle", margin:0
  });
  slide.addShape(pres.ShapeType.rect, { x:0.18, y:0.9, w:9.82, h:0.05, fill:{color:C.gold} });

  // Left col header
  slide.addShape(pres.ShapeType.rect, { x:0.3, y:1.05, w:4.5, h:0.45, fill:{color:C.teal}, line:{color:C.teal} });
  slide.addText(leftHead, { x:0.3, y:1.05, w:4.5, h:0.45, fontSize:14, bold:true, color:C.white, fontFace:"Calibri", align:"center", valign:"middle", margin:0 });
  // Right col header
  slide.addShape(pres.ShapeType.rect, { x:5.1, y:1.05, w:4.6, h:0.45, fill:{color:C.teal} });
  slide.addText(rightHead, { x:5.1, y:1.05, w:4.6, h:0.45, fontSize:14, bold:true, color:C.white, fontFace:"Calibri", align:"center", valign:"middle", margin:0 });

  // Divider
  slide.addShape(pres.ShapeType.line, { x:4.97, y:1.1, w:0, h:4.3, line:{color:C.gold, width:1.5, dashType:"dash"} });

  const makeItems = (arr) => arr.map((b, i) => {
    if (typeof b === "string") return { text:b, options:{bullet:{type:"bullet"}, color:C.navy, fontSize:15, fontFace:"Calibri", paraSpaceAfter:5, breakLine: i < arr.length-1}};
    return { text:b.text, options:{bullet: b.sub?{indent:20}:{type:"bullet"}, color:b.color||C.slate, fontSize:b.sub?13:15, bold:b.bold||false, fontFace:"Calibri", paraSpaceAfter:b.sub?2:5, breakLine: i < arr.length-1}};
  });

  slide.addText(makeItems(leftBullets), { x:0.3, y:1.6, w:4.5, h:3.9, valign:"top", margin:[4,2,2,8] });
  slide.addText(makeItems(rightBullets), { x:5.1, y:1.6, w:4.6, h:3.9, valign:"top", margin:[4,2,2,8] });
}

function tableSlide(slide, heading, headers, rows, colW) {
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.navy} });
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.18, h:"100%", fill:{color:C.gold} });
  slide.addText(heading, {
    x:0.35, y:0.1, w:9.5, h:0.7,
    fontSize:24, bold:true, color:C.white, fontFace:"Calibri", valign:"middle", margin:0
  });
  slide.addShape(pres.ShapeType.rect, { x:0.18, y:0.8, w:9.62, h:0.04, fill:{color:C.gold} });

  const tableData = [
    headers.map(h => ({ text: h, options: { bold:true, color:C.navy, fill:C.gold, fontSize:13, fontFace:"Calibri", align:"center" }})),
    ...rows.map((row, ri) => row.map(cell => ({ text: cell, options: { color:C.white, fill: ri%2===0 ? "0D2D4E" : "143355", fontSize:12, fontFace:"Calibri", align:"center" }})))
  ];
  slide.addTable(tableData, {
    x:0.25, y:0.9, w:9.5,
    colW: colW,
    border:{ pt:0.5, color:"1B7F79" },
    rowH:0.52
  });
}

function imageSlide(slide, heading, imgUrl, caption, bullets) {
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.offWhite} });
  slide.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.18, h:"100%", fill:{color:C.navy} });
  slide.addShape(pres.ShapeType.rect, { x:0.18, y:0, w:9.82, h:0.9, fill:{color:C.navy} });
  slide.addText(heading, {
    x:0.35, y:0, w:9.5, h:0.9,
    fontSize:22, bold:true, color:C.white, fontFace:"Calibri", valign:"middle", margin:0
  });
  slide.addShape(pres.ShapeType.rect, { x:0.18, y:0.9, w:9.82, h:0.05, fill:{color:C.gold} });

  if (imgUrl) {
    try {
      slide.addImage({ path: imgUrl, x:0.3, y:1.05, w:4.4, h:3.6 });
    } catch(e) {}
  }
  if (caption) {
    slide.addText(caption, { x:0.3, y:4.7, w:4.4, h:0.6, fontSize:11, italic:true, color:C.gray, fontFace:"Calibri", align:"center" });
  }
  if (bullets) {
    const items = bullets.map((b, i) => typeof b === "string"
      ? { text:b, options:{bullet:{type:"bullet"}, color:C.navy, fontSize:15, fontFace:"Calibri", paraSpaceAfter:6, breakLine: i < bullets.length-1}}
      : { text:b.text, options:{bullet:b.sub?{indent:20}:{type:"bullet"}, color:b.color||C.slate, fontSize:b.sub?13:15, bold:b.bold||false, fontFace:"Calibri", paraSpaceAfter:b.sub?3:6, breakLine: i < bullets.length-1}});
    slide.addText(items, { x:4.9, y:1.05, w:4.9, h:4.2, valign:"top", margin:[4,4,4,10] });
  }
}

// ══════════════════════════════════════════════════════════════════
// SLIDE 1 — TITLE
// ══════════════════════════════════════════════════════════════════
let s = pres.addSlide();
titleSlide(s,
  "Macular Function Tests\n& Macular Dystrophy",
  "A Comprehensive Review for Ophthalmology Residents"
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 2 — OVERVIEW / TABLE OF CONTENTS
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
slide2 = s;
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.navy} });
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.18, h:"100%", fill:{color:C.gold} });
s.addText("Lecture Overview", {
  x:0.4, y:0.15, w:9.4, h:0.7,
  fontSize:26, bold:true, color:C.white, fontFace:"Calibri"
});
s.addShape(pres.ShapeType.rect, { x:0.18, y:0.85, w:9.62, h:0.04, fill:{color:C.gold} });

const sections = [
  ["01", "Anatomy of the Macula — a quick review"],
  ["02", "Macular Function Tests — classification & overview"],
  ["03", "Psychophysical Tests — Amsler, Photostress, Two-Point, Maddox Rod"],
  ["04", "Electrophysiological Tests — ERG, EOG, VEP"],
  ["05", "Tests for Potential Vision — PAM, Laser Interferometry, Entoptic"],
  ["06", "Microperimetry & OCT-based Functional Assessment"],
  ["07", "Introduction to Macular Dystrophies"],
  ["08", "Stargardt Disease"],
  ["09", "Best Vitelliform Macular Dystrophy"],
  ["10", "Other Dystrophies: Pattern, Sorsby, North Carolina, Cone"],
  ["11", "Investigations & Management"],
];

sections.forEach(([num, title], i) => {
  const col = i < 6 ? 0 : 1;
  const row = i < 6 ? i : i - 6;
  const x = col === 0 ? 0.4 : 5.3;
  const y = 1.0 + row * 0.68;
  s.addShape(pres.ShapeType.rect, { x:x, y:y, w:0.5, h:0.45, fill:{color:C.teal} });
  s.addText(num, { x:x, y:y, w:0.5, h:0.45, fontSize:13, bold:true, color:C.gold, fontFace:"Calibri", align:"center", valign:"middle", margin:0 });
  s.addText(title, { x:x+0.6, y:y+0.04, w:4.2, h:0.38, fontSize:13, color:C.light, fontFace:"Calibri", valign:"middle" });
});

// ══════════════════════════════════════════════════════════════════
// SLIDE 3 — MACULA ANATOMY
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Anatomy of the Macula — Quick Review", [
  {text:"Definition", bold:true, color:C.teal},
  {text:"Specialised area of central retina, ~5.5 mm diameter, centred at the fovea (~4 mm temporal to optic disc)", sub:true},
  {text:"Histological definition: retinal area with > 2 layers of ganglion cells", sub:true},
  {text:"Zones (centre outward)", bold:true, color:C.teal},
  {text:"Foveola (0.35 mm) — cone-only, thinnest retina, highest acuity", sub:true},
  {text:"Fovea centralis (1.5 mm) — includes foveola + surrounding slope", sub:true},
  {text:"Parafovea (2.5 mm) — densest ganglion cells", sub:true},
  {text:"Perifovea (5.5 mm) — outer boundary of macula", sub:true},
  {text:"Key structural features", bold:true, color:C.teal},
  {text:"Xanthophyll pigment (lutein + zeaxanthin) — protects against phototoxicity", sub:true},
  {text:"Retinal pigment epithelium (RPE) — essential for photoreceptor support & visual cycle", sub:true},
  {text:"Bruch's membrane separates RPE from choriocapillaris", sub:true},
  {text:"Müller cells form foveal pit structure", sub:true},
  {text:"Clinical importance", bold:true, color:C.teal},
  {text:"Responsible for central vision, colour vision, fine detail discrimination", sub:true},
  {text:"Damage → central scotoma, metamorphopsia, reduced Snellen acuity", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 4 — SECTION HEADER: MACULAR FUNCTION TESTS
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
sectionHeader(s, "01", "Macular Function Tests", "Classification & Clinical Rationale");

// ══════════════════════════════════════════════════════════════════
// SLIDE 5 — CLASSIFICATION OF MFTs
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
tableSlide(s,
  "Classification of Macular Function Tests",
  ["Category", "Test", "Media Opacity?", "Primary Use"],
  [
    ["Psychophysical", "Amsler Grid", "Clear / mild", "Detect metamorphopsia, scotoma"],
    ["Psychophysical", "Photostress Test", "Clear / mild", "Macular vs optic nerve disease"],
    ["Psychophysical", "Two-Point Discrimination", "Clear", "Gross macular screen"],
    ["Psychophysical", "Maddox Rod Test", "Clear", "Metamorphopsia assessment"],
    ["Electrophysiological", "Full-Field ERG", "Any", "Retinal function, dystrophies"],
    ["Electrophysiological", "Multifocal ERG (mfERG)", "Clear", "Localised macular function"],
    ["Electrophysiological", "Electrooculogram (EOG)", "Any", "RPE function (Best disease)"],
    ["Electrophysiological", "Visual Evoked Potential (VEP)", "Any", "Cortical visual pathway"],
    ["Potential Vision", "Potential Acuity Meter (PAM)", "Dense cataract", "Pre-op acuity prediction"],
    ["Potential Vision", "Laser Interferometry", "Dense cataract", "Pre-op acuity prediction"],
    ["Potential Vision", "Entoptic Phenomena", "Any", "Gross retinal function"],
    ["Special", "Microperimetry (MP-1, MAIA)", "Clear", "Retinal sensitivity mapping"],
  ],
  [2.1, 2.2, 1.5, 3.7]
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 6 — AMSLER GRID
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
twoColSlide(s,
  "Amsler Grid",
  "Technique",
  [
    "7 variants (white, red, dotted, etc.); Chart I (standard) most used",
    "Held at 33 cm from eye (covers central 20° of visual field)",
    "Patient wears near correction; one eye at a time",
    "Room lighting adequate; avoid pre-test bright illumination (photostress effect)",
    "Patient fixates central dot and reports any distortion or missing areas",
    "Mark defects on chart for serial monitoring",
    {text:"Results:", bold:true},
    {text:"Normal: all lines straight, all squares equal, central dot visible", sub:true},
    {text:"Metamorphopsia: lines appear wavy/distorted", sub:true},
    {text:"Scotoma: area appears missing/blurred", sub:true},
    {text:"Micropsia/macropsia: squares appear smaller/larger", sub:true},
  ],
  "Clinical Points",
  [
    {text:"Indications", bold:true},
    {text:"Diagnosis & monitoring of macular disease (AMD, CRVO, CSR, dystrophies)", sub:true},
    {text:"Pre-op macular screen before cataract surgery", sub:true},
    {text:"Home monitoring in AMD — daily use recommended (AAO)", sub:true},
    {text:"Limitations", bold:true},
    {text:"Low sensitivity for small central scotomata", sub:true},
    {text:"Better eye may suppress defect in binocular testing", sub:true},
    {text:"False negatives in patients with poor fixation", sub:true},
    {text:"Cannot quantify size or depth of scotoma reliably", sub:true},
    {text:"Alternatives", bold:true},
    {text:"M-charts (quantify metamorphopsia)", sub:true},
    {text:"PreView PHP — computerised version", sub:true},
    {text:"Microperimetry for precise mapping", sub:true},
  ]
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 7 — PHOTOSTRESS TEST
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Photostress Recovery Test (PSRT)", [
  {text:"Principle", bold:true, color:C.teal},
  {text:"Bright light bleaches macular photopigments → transient scotoma", sub:true},
  {text:"PSRT = time for visual acuity to return to baseline after photostress", sub:true},
  {text:"Dependent on: RPE–photoreceptor regeneration of visual pigment (11-cis-retinal cycle)", sub:true},
  {text:"Technique", bold:true, color:C.teal},
  {text:"Record baseline BCVA in each eye separately", sub:true},
  {text:"Direct bright penlight at eye for 10 seconds at 5 cm from cornea", sub:true},
  {text:"Time taken for VA to recover to within 1 line of baseline = PSRT", sub:true},
  {text:"Normal PSRT: ≤ 50 seconds; Abnormal: > 60–90 seconds", sub:true},
  {text:"Interpretation", bold:true, color:C.teal},
  {text:"Prolonged PSRT (>50 s) → macular disease (AMD, CSCR, macular dystrophy, macular oedema)", sub:true, color:C.red},
  {text:"Normal PSRT (≤50 s) with poor VA → optic nerve disease or media opacity", sub:true, color:C.green},
  {text:"Independent of media opacity; test only retinal function", sub:true},
  {text:"Clinical value: differentiates macular vs. optic nerve aetiology of vision loss", sub:true},
  {text:"Limitations", bold:true, color:C.teal},
  {text:"Subjective; requires patient cooperation", sub:true},
  {text:"Not reliable in dense media opacities", sub:true},
  {text:"Cannot localise the lesion; over-predicts recovery in optic neuropathies", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 8 — TWO-POINT DISCRIMINATION + MADDOX ROD + ENTOPTIC
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Other Psychophysical & Gross Macular Tests", [
  {text:"Two-Point Discrimination Test", bold:true, color:C.teal},
  {text:"Two 2-mm lights held 5 cm apart at 60 cm — patient identifies if 2 separate lights seen", sub:true},
  {text:"Normal: two separate lights perceived → adequate macular function", sub:true},
  {text:"Good for children/uncooperative patients; requires clear media", sub:true},
  {text:"Maddox Rod Test (for metamorphopsia)", bold:true, color:C.teal},
  {text:"Maddox rod held before eye — converts point source of light into a streak", sub:true},
  {text:"Normal: streak appears straight; Metamorphopsia: streak appears wavy/bent", sub:true},
  {text:"Can be combined with Hess chart for quantification", sub:true},
  {text:"Entoptic Phenomena", bold:true, color:C.teal},
  {text:"Haidinger brush: rotating bowtie pattern seen with polarised blue light → intact foveal cone function", sub:true},
  {text:"Blue field entoptic (Scheerer's phenomenon): small bright corpuscles darting across field → intact macular blood flow & retinal function; >15 corpuscles = normal", sub:true},
  {text:"Retinal vascular arborisation shadow: shadow of retinal vessels seen in bright diffuse illumination; absent or poor = poor macular function", sub:true},
  {text:"Useful when media is too opaque for direct visualisation", sub:true},
  {text:"Colour Vision Testing", bold:true, color:C.teal},
  {text:"Ishihara, Farnsworth-Munsell 100-Hue, City University — detect colour axis of defect", sub:true},
  {text:"Important screening tool in cone dystrophies, Stargardt, chloroquine toxicity", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 9 — ELECTROPHYSIOLOGY (ERG/EOG/VEP)
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
tableSlide(s,
  "Electrophysiological Tests — ERG, EOG, VEP",
  ["Test", "What It Measures", "Key Finding in Macular Disease", "Clinical Application"],
  [
    ["Full-Field ERG\n(ffERG)", "Mass retinal response (photoreceptors + bipolar cells)", "Often normal in isolated macular dystrophies\n(affects <5% retinal area)", "Cone vs rod dysfunction;\nEstablish disease extent"],
    ["Pattern ERG\n(PERG)", "Macular / ganglion cell function\n(P50 & N95 waves)", "P50 reduced/absent in macular dystrophy;\nN95 affected in optic nerve disease", "Differentiates macular\nfrom optic nerve origin"],
    ["Multifocal ERG\n(mfERG)", "Local retinal sensitivity\nacross central 50°", "Localised amplitude reduction\nover dystrophic area", "Best functional map\nof macular lesions"],
    ["Electrooculogram\n(EOG)", "RPE function\n(Arden ratio = light peak/dark trough)", "Arden ratio <1.5 = subnormal;\nHallmark of Best disease", "MANDATORY in suspected\nBest vitelliform dystrophy"],
    ["Visual Evoked\nPotential (VEP)", "Cortical response from\nentire visual pathway", "Reduced amplitude / delayed\nP100 in macular dysfunction", "Rule out cortical or\noptic pathway disease"],
  ],
  [1.9, 2.3, 2.3, 2.5]
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 10 — PAM + LASER INTERFEROMETRY
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
twoColSlide(s,
  "Tests for Potential Vision (Opaque Media)",
  "Potential Acuity Meter (PAM)",
  [
    "Projects miniature Snellen chart through a tiny clear area of cataract using +12D lens + bright light",
    "Main components: bright source, miniature transilluminated chart",
    "Pupil should be widely dilated; patient reads chart",
    "Smallest line readable by ≥3 chars = potential acuity",
    "Most accurate for VA ≥ 6/60",
    {text:"Advantage: easy, familiar Snellen format", sub:true},
    {text:"Limitation: over-estimates acuity in dense/posterior subcapsular cataract; unreliable in macular disease", sub:true, color:C.red},
    {text:"Pre-cataract surgical counselling", bold:true},
    {text:"Warn patients if macular pathology likely to limit outcome", sub:true},
  ],
  "Laser Interferometry (Retinometer)",
  [
    "Two coherent laser beams (He-Ne, 632 nm) create interference fringes on retina bypassing optical media",
    "Patient adjusts fringe spacing until just resolvable — correlates with grating acuity",
    "Not dependent on refractive error or optical quality of cornea/lens",
    {text:"Advantage: penetrates dense cataracts; quantitative", sub:true},
    {text:"Limitation: over-predicts potential in amblyopia; fails in total cataract (no light transmission)", sub:true, color:C.red},
    {text:"Comparison of PAM vs Interferometry", bold:true},
    {text:"PAM: better for moderate-severe cataract with retained VA ≥ 6/60", sub:true},
    {text:"Interferometry: better for dense posterior subcapsular cataract", sub:true},
    {text:"Both: false optimism if dense macular disease co-exists", sub:true, color:C.red},
  ]
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 11 — MICROPERIMETRY
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Microperimetry — Fundus-Related Visual Field Testing", [
  {text:"Principle", bold:true, color:C.teal},
  {text:"Combines fundus imaging (SLO) with automated perimetry — each stimulus precisely located on fundus image", sub:true},
  {text:"Measures retinal sensitivity (dB) at defined retinal loci with simultaneous fixation tracking", sub:true},
  {text:"Instruments: MP-1 (Nidek), MAIA (Centervue), Spectralis (Heidelberg) — all differ in SLO vs colour image, testing protocols", sub:true},
  {text:"Parameters Measured", bold:true, color:C.teal},
  {text:"Macular sensitivity: normal foveal threshold ≥ 25–27 dB", sub:true},
  {text:"Fixation stability: PRL (Preferred Retinal Locus), BCEA (Bivariate Contour Ellipse Area)", sub:true},
  {text:"Fixation location: foveal vs para-foveal — important in macular atrophy", sub:true},
  {text:"Clinical Applications in Macular Dystrophy", bold:true, color:C.teal},
  {text:"Characterise functional loss pattern in Stargardt, Best, cone dystrophy", sub:true},
  {text:"Monitor disease progression and treatment response", sub:true},
  {text:"Correlate structural OCT changes with functional deficit", sub:true},
  {text:"Identify viable retina for potential gene therapy targeting", sub:true},
  {text:"Rehabilitation: guide eccentric viewing training using preferred retinal locus data", sub:true},
  {text:"Advantages over Standard Perimetry", bold:true, color:C.teal},
  {text:"Direct structure–function correlation; patient fixation does not affect accuracy", sub:true},
  {text:"Suitable for patients with unstable/eccentric fixation — a common problem in macular dystrophies", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 12 — SECTION HEADER: MACULAR DYSTROPHY
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
sectionHeader(s, "02", "Macular Dystrophies", "Classification, Clinical Features & Management");

// ══════════════════════════════════════════════════════════════════
// SLIDE 13 — INTRODUCTION TO MACULAR DYSTROPHIES
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Macular Dystrophies — Introduction & Classification", [
  {text:"Definition", bold:true, color:C.teal},
  {text:"Inherited genetic disorders causing progressive, bilateral, symmetric macular degeneration", sub:true},
  {text:"Distinct from AMD: earlier onset, genetic basis, no systemic vascular risk factors", sub:true},
  {text:"Key presenting features", bold:true, color:C.teal},
  {text:"Central vision loss (scotoma) with preserved peripheral vision", sub:true},
  {text:"Colour vision defects (especially in cone dystrophies)", sub:true},
  {text:"Metamorphopsia (distortion) with macular deposits/accumulation", sub:true},
  {text:"Often bilateral but asymmetric in early stages", sub:true},
  {text:"Classification by primary layer involved", bold:true, color:C.teal},
  {text:"Photoreceptor layer: Stargardt (ABCA4), Cone Dystrophy, Cone-Rod Dystrophy", sub:true},
  {text:"RPE layer: Best Vitelliform (BEST1), Pattern Dystrophies (PRPH2)", sub:true},
  {text:"Bruch's membrane / RPE-choriocapillaris: Sorsby fundus dystrophy (TIMP3), Familial Drusen (EFEMP1)", sub:true},
  {text:"Complex / unknown: North Carolina Macular Dystrophy (PRDM13)", sub:true},
  {text:"Important investigations for all macular dystrophies", bold:true, color:C.teal},
  {text:"BCVA, colour vision, Amsler grid, fundus photography, FAF, OCT, FA, ERG, EOG, genetic testing", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 14 — STARGARDT DISEASE
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Stargardt Disease (STGD1) — Most Common Juvenile Macular Dystrophy", [
  {text:"Epidemiology & Genetics", bold:true, color:C.teal},
  {text:"Most common inherited macular dystrophy; prevalence 1:8,000–10,000", sub:true},
  {text:"STGD1 (AR): ABCA4 gene mutation (chr 1p) → defective clearance of retinoid by-products → lipofuscin accumulation in RPE", sub:true},
  {text:"STGD3 (AD): ELOVL4 gene; STGD4 (AD): PROM1 gene (rare)", sub:true},
  {text:"Clinical Features", bold:true, color:C.teal},
  {text:"Onset: childhood–young adulthood (typically < 25 yrs); vision loss disproportionate to fundus findings early on", sub:true},
  {text:"Bilateral, symmetric central vision loss; central scotoma", sub:true},
  {text:"Colour vision frequently impaired", sub:true},
  {text:"Fundoscopy findings", bold:true, color:C.teal},
  {text:"Early: normal-appearing fundus or subtle foveal granularity", sub:true},
  {text:"Pisciform (fish-tail) yellow-white flecks at level of RPE — pathognomonic", sub:true},
  {text:"'Beaten-bronze' or 'beaten-metal' macular appearance", sub:true},
  {text:"Bull's-eye maculopathy; geographic atrophy in advanced disease", sub:true},
  {text:"Prognosis", bold:true, color:C.teal},
  {text:"VA often deteriorates to 6/60 or worse; once < 6/12 tends to worsen rapidly", sub:true},
  {text:"ERG: normal early, may become abnormal late; cone-rod pattern in some", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 15 — STARGARDT INVESTIGATIONS
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
twoColSlide(s,
  "Stargardt Disease — Investigations",
  "Imaging Findings",
  [
    {text:"Fluorescein Angiography (FA)", bold:true},
    {text:"'Silent choroid' (dark choroid) — PATHOGNOMONIC in ~80%", sub:true, color:C.gold},
    {text:"Choroidal fluorescence blocked by lipofuscin in RPE", sub:true},
    {text:"Macular hyperfluorescence (window defect) in atrophic areas", sub:true},
    {text:"Fundus Autofluorescence (FAF)", bold:true},
    {text:"Hyperautofluorescent flecks = lipofuscin accumulation", sub:true},
    {text:"Hypoautofluorescent areas = RPE/photoreceptor atrophy", sub:true},
    {text:"OCT", bold:true},
    {text:"Outer retinal atrophy, ellipsoid zone disruption, RPE loss", sub:true},
    {text:"Hyperreflective deposits in outer retina", sub:true},
    {text:"Adaptive Optics + Wide-Field Imaging", bold:true},
    {text:"Demonstrate peripheral fleck extension in some patients", sub:true},
  ],
  "Electrophysiology & Genetics",
  [
    {text:"ERG Groups (Fishman classification)", bold:true},
    {text:"Group 1 (normal ffERG): isolated macular disease, best prognosis", sub:true, color:C.green},
    {text:"Group 2 (abnormal cone ERG): cone-rod pattern, intermediate", sub:true},
    {text:"Group 3 (abnormal rod + cone ERG): panretinal disease, worst prognosis", sub:true, color:C.red},
    {text:"Pattern ERG: reduced P50 amplitude", sub:true},
    {text:"EOG: can be subnormal", sub:true},
    {text:"Genetic Testing", bold:true},
    {text:"ABCA4 panel sequencing — confirms diagnosis, aids counselling", sub:true},
    {text:"Allows classification A–D by mutation severity", sub:true},
    {text:"Differential Diagnosis", bold:true},
    {text:"AMD (older patients, no flecks)", sub:true},
    {text:"Chloroquine/hydroxychloroquine toxicity", sub:true},
    {text:"Cone dystrophy, bull's-eye maculopathy", sub:true},
    {text:"Fundus albipunctatus (stationary, peripheral dots)", sub:true},
  ]
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 16 — BEST VITELLIFORM MACULAR DYSTROPHY
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Best Vitelliform Macular Dystrophy (BVMD)", [
  {text:"Genetics & Pathogenesis", bold:true, color:C.teal},
  {text:"BEST1 gene (chr 11q13) — encodes bestrophin: Ca²⁺-activated Cl⁻ channel in RPE", sub:true},
  {text:"Autosomal dominant with variable penetrance & expressivity", sub:true},
  {text:"2nd most common macular dystrophy after Stargardt disease", sub:true},
  {text:"Defective bestrophin → impaired fluid transport → lipofuscin-like material accumulates subretinally", sub:true},
  {text:"Stages (Gass Classification)", bold:true, color:C.teal},
  {text:"Stage 1 — Pre-vitelliform: subnormal EOG, normal fundus; asymptomatic", sub:true},
  {text:"Stage 2 — Vitelliform: classic 'sunny-side-up egg yolk' yellow macular lesion (0.5–2 DD)", sub:true, color:C.gold},
  {text:"Stage 3 — Pseudohypopyon: material gravitates inferiorly → horizontal level", sub:true},
  {text:"Stage 4 — Vitelliruptive: lesion breaks up, 'scrambled egg'; vision begins to deteriorate", sub:true},
  {text:"Stage 5 — Atrophic: RPE + photoreceptor atrophy; significant VA loss", sub:true, color:C.red},
  {text:"Stage 6 — Fibrovascular scar (if MNV develops)", sub:true, color:C.red},
  {text:"Electrophysiology — KEY DIAGNOSTIC FINDING", bold:true, color:C.teal},
  {text:"EOG: grossly subnormal Arden ratio < 1.5 at ALL stages — even in carriers with normal fundus", sub:true, color:C.gold},
  {text:"ERG: usually normal (differentiates from extensive retinal disease)", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 17 — BEST DISEASE INVESTIGATIONS
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Best Disease — Investigations & Management", [
  {text:"Investigations", bold:true, color:C.teal},
  {text:"EOG: Arden ratio < 1.5 — pathognomonic; abnormal even in pre-vitelliform carriers", sub:true, color:C.gold},
  {text:"FAF: vitelliform material = intensely hyperautofluorescent; atrophic stage = hypoautofluorescent", sub:true},
  {text:"FA: hypofluorescence of vitelliform lesion (masking); hyperfluorescence in window defects", sub:true},
  {text:"OCT: subretinal dome-shaped hyperreflective material above RPE; fluid-filled space in pseudohypopyon", sub:true},
  {text:"Genetic testing: BEST1 sequencing — essential for family counselling; also tests for PRPH2, IMPG2 (AOVMD)", sub:true},
  {text:"Prognosis", bold:true, color:C.teal},
  {text:"Usually good until middle age; one or both eyes may deteriorate due to atrophy or MNV", sub:true},
  {text:"Visual acuity often preserved until vitelliruptive/atrophic stage", sub:true},
  {text:"~20% develop choroidal neovascularisation (MNV) → anti-VEGF indicated", sub:true},
  {text:"Management", bold:true, color:C.teal},
  {text:"No proven treatment for the underlying disease currently", sub:true},
  {text:"Anti-VEGF (ranibizumab, aflibercept, bevacizumab) for complicating MNV", sub:true},
  {text:"Low vision aids, genetic counselling, annual monitoring", sub:true},
  {text:"Gene therapy trials ongoing (BEST1-targeted AAV vectors)", sub:true},
  {text:"Adult-Onset Vitelliform (AOVMD)", bold:true, color:C.teal},
  {text:"Similar yellow foveal deposits in patients > 40 yrs; normal EOG; mutations in PRPH2, IMPG2 or BEST1", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 18 — PATTERN DYSTROPHIES + SORSBY
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
twoColSlide(s,
  "Pattern Dystrophies & Sorsby Fundus Dystrophy",
  "Pattern Dystrophies of the RPE",
  [
    "Heterogeneous group of AD macular diseases",
    "PRPH2 (peripherin/RDS) gene mutations — chr 6p21",
    "Onset: 4th–6th decade; generally mild vision loss",
    {text:"Types:", bold:true},
    {text:"Butterfly-shaped dystrophy (triradiate pigment at fovea)", sub:true},
    {text:"Reticular (fishnet) dystrophy", sub:true},
    {text:"Adult-onset foveomacular vitelliform (AOVMD)", sub:true},
    {text:"Fundus pulverulentus", sub:true},
    {text:"Multifocal pattern dystrophy simulating Stargardt", sub:true},
    "EOG: normal (unlike Best) — important differential",
    "ERG: normal",
    "OCT: subretinal deposits, outer retinal disruption",
    "Treatment: supportive; anti-VEGF for complicating MNV",
  ],
  "Sorsby Fundus Dystrophy",
  [
    "TIMP3 gene mutation (chr 22q) — AD",
    "Defective TIMP3 → abnormal Bruch's membrane metabolism",
    "Onset: 4th–5th decade",
    {text:"Features:", bold:true},
    {text:"Bilateral symmetric subretinal drusenoid deposits", sub:true},
    {text:"Central vision loss + nyctalopia (night blindness)", sub:true},
    {text:"Extensive choroidal neovascularisation common", sub:true},
    {text:"Fundus: yellow-white peripheral deposits + macular scar", sub:true},
    "ERG: subnormal rod and cone responses",
    "EOG: subnormal",
    "MRI of Bruch's: thickened, abnormal",
    {text:"Treatment:", bold:true},
    {text:"Vitamin A supplementation (high-dose) may slow RPE degeneration", sub:true},
    {text:"Anti-VEGF for MNV", sub:true},
    {text:"Differentiate from AMD: younger age, AD inheritance, peripheral deposits", sub:true, color:C.gold},
  ]
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 19 — OTHER DYSTROPHIES
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Other Macular Dystrophies", [
  {text:"North Carolina Macular Dystrophy (NCMD)", bold:true, color:C.teal},
  {text:"PRDM13 gene, chr 6q; autosomal dominant; rare", sub:true},
  {text:"Non-progressive; drusen-like macular & peripheral deposits from 1st decade", sub:true},
  {text:"Grade 1: scattered yellow-white deposits; Grade 2: confluent macular deposits; Grade 3: atrophic macular coloboma", sub:true},
  {text:"FAF: peripheral hyperautofluorescent streaks — characteristic; ERG: normal", sub:true},
  {text:"Cone Dystrophy", bold:true, color:C.teal},
  {text:"Pure cone photoreceptor dysfunction; AR, AD or X-linked", sub:true},
  {text:"Onset: 1st–3rd decade; profound colour vision loss, severe photophobia, nystagmus", sub:true},
  {text:"Bull's-eye maculopathy on fundus; dark adaptation normal", sub:true},
  {text:"ERG: absent/severely reduced photopic (cone) response; scotopic (rod) response preserved", sub:true, color:C.gold},
  {text:"Achromatopsia (congenital stationary cone dystrophy): CNGB3, CNGA3 mutations", sub:true},
  {text:"Familial Dominant Drusen (Doyne Honeycomb / Malattia Leventinese)", bold:true, color:C.teal},
  {text:"EFEMP1 gene (chr 2p16); AD; radially oriented macular drusen from 2nd decade", sub:true},
  {text:"Honeycomb pattern with age; MNV in older patients; ERG normal, EOG subnormal late", sub:true},
  {text:"Macular Corneal Dystrophy (note: CORNEAL, not retinal)", bold:true, color:C.teal},
  {text:"CHST6 gene; AR stromal corneal dystrophy; cloudy stroma with ill-defined edges", sub:true},
  {text:"Reduced vision due to corneal haze, not macular disease — important distinction!", sub:true, color:C.red},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 20 — INVESTIGATION SUMMARY TABLE
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
tableSlide(s,
  "Electrophysiology Summary — Macular Dystrophies",
  ["Disease", "ffERG", "Pattern ERG", "EOG (Arden)", "FAF", "Key Genetic Test"],
  [
    ["Stargardt STGD1", "Normal early\n(Group 1)\nAbnormal late\n(Groups 2–3)", "Reduced P50", "Subnormal\n(may be normal)", "Hyper flecks\n+ hypo atrophy", "ABCA4"],
    ["Best Vitelliform", "Normal", "Normal", "SEVERELY subnormal\n< 1.5 (hallmark)", "Hyper vitelliform\nHypo atrophic", "BEST1"],
    ["Pattern Dystrophy", "Normal", "Normal or\nmildly reduced", "Normal\n(key differential)", "Variable pattern\ndeposits", "PRPH2"],
    ["Sorsby FD", "Subnormal\n(rod + cone)", "Reduced", "Subnormal", "Drusenoid\ndeposits", "TIMP3"],
    ["Cone Dystrophy", "Severely reduced\nphotopic only", "Reduced P50", "Normal", "Bull's-eye\nmaculopathy", "CNGB3, CNGA3\nGUCY2D etc"],
    ["North Carolina MD", "Normal", "Normal", "Normal", "Peripheral\nhyper streaks", "PRDM13"],
    ["Familial Drusen", "Normal", "Normal", "Subnormal\n(late)", "Drusen\nhyperauto", "EFEMP1"],
  ],
  [2.2, 1.5, 1.5, 1.8, 1.5, 1.5]
);

// ══════════════════════════════════════════════════════════════════
// SLIDE 21 — MANAGEMENT OF MACULAR DYSTROPHIES
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
contentSlide(s, "Management of Macular Dystrophies — General Principles", [
  {text:"No curative treatment currently available for most inherited macular dystrophies", bold:true, color:C.red},
  {text:"Patient education", bold:true, color:C.teal},
  {text:"Explain natural history and prognosis — crucial for informed decision-making", sub:true},
  {text:"Avoid smoking — exacerbates oxidative RPE damage", sub:true},
  {text:"UV-protective sunglasses — reduce phototoxic stress", sub:true},
  {text:"Avoid vitamin A supplementation in ABCA4 diseases (increases A2E toxin in RPE)", sub:true, color:C.red},
  {text:"Genetic counselling", bold:true, color:C.teal},
  {text:"Confirm molecular diagnosis with comprehensive retinal gene panel", sub:true},
  {text:"Determine inheritance pattern; counsel family members; consider reproductive options (PGT)", sub:true},
  {text:"Symptomatic / supportive treatment", bold:true, color:C.teal},
  {text:"Low vision aids: magnifiers, telescopic lenses, electronic devices (OrCam, tablet apps)", sub:true},
  {text:"Anti-VEGF (ranibizumab, aflibercept) for complicating choroidal neovascularisation (MNV)", sub:true},
  {text:"Emerging & investigational therapies", bold:true, color:C.teal},
  {text:"Gene therapy (AAV vectors): RPGR, BEST1, CNGA3 — Phase I/II trials ongoing", sub:true},
  {text:"Cell therapy: hESC-derived RPE (ASP7317) — Phase Ib trials in Stargardt (Astellas, 2024–25)", sub:true},
  {text:"Pharmacology: Emixustat (visual cycle modulator, A2E reduction), deuterated vitamin A (ALK-001)", sub:true},
  {text:"Optogenetics: ChR2 / ChrimsonR channelrhodopsin for late-stage photoreceptor loss", sub:true},
  {text:"CRISPR/Cas9 gene editing: preclinical studies in ABCA4 and BEST1 models", sub:true},
]);

// ══════════════════════════════════════════════════════════════════
// SLIDE 22 — CLINICAL APPROACH ALGORITHM
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.navy} });
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.18, h:"100%", fill:{color:C.teal} });
s.addText("Clinical Approach to Suspected Macular Dystrophy", {
  x:0.35, y:0.05, w:9.5, h:0.75,
  fontSize:22, bold:true, color:C.white, fontFace:"Calibri", valign:"middle", margin:0
});
s.addShape(pres.ShapeType.rect, { x:0.18, y:0.8, w:9.62, h:0.04, fill:{color:C.gold} });

// Flowchart boxes
const boxes = [
  { x:3.5, y:0.95, w:3.5, h:0.5, text:"Central vision loss\n(young adult)", fill:C.teal },
  { x:3.5, y:1.65, w:3.5, h:0.5, text:"Complete history:\nfamily, onset, drugs, systemic", fill:"143355" },
  { x:3.5, y:2.35, w:3.5, h:0.5, text:"BCVA · Colour vision\nAmsler grid · Fundus exam", fill:"143355" },
  { x:3.5, y:3.05, w:3.5, h:0.5, text:"OCT · FAF · FA", fill:"143355" },
  { x:0.4, y:3.75, w:2.8, h:0.5, text:"ERG + EOG + VEP", fill:C.gold },
  { x:3.5, y:3.75, w:3.5, h:0.5, text:"Genetic panel\n(targeted or WES)", fill:"143355" },
  { x:6.7, y:3.75, w:2.8, h:0.5, text:"Microperimetry\n(functional mapping)", fill:C.gold },
  { x:3.5, y:4.55, w:3.5, h:0.5, text:"Diagnosis → Counselling\n→ Management plan", fill:C.teal },
];

boxes.forEach(b => {
  s.addShape(pres.ShapeType.rect, { x:b.x, y:b.y, w:b.w, h:b.h, fill:{color:b.fill}, line:{color:C.gold, pt:1}, rectRadius:0.05 });
  s.addText(b.text, { x:b.x, y:b.y, w:b.w, h:b.h, fontSize:12, bold:true, color:b.fill===C.gold?C.navy:C.white, fontFace:"Calibri", align:"center", valign:"middle", margin:0 });
});

// Arrows (as thin rectangles)
[[5.25,1.45,0.1,0.2],[5.25,2.15,0.1,0.2],[5.25,2.85,0.1,0.2],[5.25,3.55,0.1,0.2]].forEach(([x,y,w,h])=>{
  s.addShape(pres.ShapeType.rect,{x,y,w,h,fill:{color:C.gold}});
});

// ══════════════════════════════════════════════════════════════════
// SLIDE 23 — KEY POINTS & EXAM PEARLS
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.navy} });
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.18, h:"100%", fill:{color:C.gold} });
s.addText("Key Points & Examination Pearls", {
  x:0.35, y:0.05, w:9.5, h:0.75,
  fontSize:24, bold:true, color:C.white, fontFace:"Calibri", valign:"middle"
});
s.addShape(pres.ShapeType.rect, { x:0.18, y:0.8, w:9.62, h:0.04, fill:{color:C.teal} });

const pearls = [
  ["Photostress test:", "Prolonged PSRT (>50 s) = macular disease; Normal PSRT with poor VA = optic nerve lesion"],
  ["EOG Arden < 1.5:", "Pathognomonic of Best vitelliform dystrophy — abnormal even before fundus changes appear"],
  ["Silent choroid on FA:", "~80% pathognomonic for Stargardt (ABCA4); lipofuscin blocks choroidal fluorescence"],
  ["ffERG normal:", "In macular dystrophies (isolated) — macular area is <5% of total retina"],
  ["Pattern ERG P50 ↓:", "Indicates macular ganglion cell / photoreceptor dysfunction — useful objective measure"],
  ["EOG normal in Pattern Dystrophies:", "Key differential from Best disease (same age group, similar deposits)"],
  ["Vitamin A avoidance:", "In ABCA4 Stargardt — vitamin A ↑ A2E formation → accelerated RPE toxicity"],
  ["NCMD:", "Non-progressive despite dramatic fundus appearance — do not over-treat"],
  ["Gene therapy outlook:", "ABCA4, BEST1, CNGB3 — active trials; genetic testing now standard of care"],
];

pearls.forEach(([key, val], i) => {
  const y = 0.9 + i * 0.52;
  s.addShape(pres.ShapeType.rect, { x:0.3, y:y, w:9.4, h:0.46, fill:{color: i%2===0 ? "0D2D4E" : "143355"}, line:{color:C.teal, pt:0.5} });
  s.addText([
    { text: key + "  ", options: { bold:true, color:C.gold, fontSize:13, fontFace:"Calibri" } },
    { text: val, options: { color:C.white, fontSize:13, fontFace:"Calibri" } }
  ], { x:0.4, y:y, w:9.2, h:0.46, valign:"middle", margin:[0,4,0,6] });
});

// ══════════════════════════════════════════════════════════════════
// SLIDE 24 — THANK YOU
// ══════════════════════════════════════════════════════════════════
s = pres.addSlide();
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:"100%", h:"100%", fill:{color:C.navy} });
s.addShape(pres.ShapeType.rect, { x:0, y:2.55, w:"100%", h:0.06, fill:{color:C.gold} });
s.addShape(pres.ShapeType.rect, { x:0, y:2.62, w:"100%", h:0.06, fill:{color:C.teal} });
s.addShape(pres.ShapeType.rect, { x:0, y:0, w:0.25, h:"100%", fill:{color:C.teal} });
s.addText("Thank You", {
  x:0.5, y:0.6, w:9, h:1.6,
  fontSize:52, bold:true, color:C.white, fontFace:"Calibri", align:"center"
});
s.addText("Questions & Discussion", {
  x:0.5, y:2.8, w:9, h:0.8,
  fontSize:22, color:C.light, fontFace:"Calibri", align:"center", italic:true
});
s.addText([
  { text: "References: ", options:{bold:true, color:C.gold, fontSize:13} },
  { text: "Kanski's Clinical Ophthalmology 10e  |  Wills Eye Manual 8e  |  StatPearls NBK587444  |  Review of Ophthalmology 2024", options:{color:C.gray, fontSize:13} }
], { x:0.5, y:4.2, w:9, h:0.8, align:"center", valign:"middle" });

// ══════════════════════════════════════════════════════════════════
// WRITE FILE
// ══════════════════════════════════════════════════════════════════
pres.writeFile({ fileName: "/home/daytona/workspace/macular-ppt/Macular_Function_Tests_and_Dystrophy.pptx" })
  .then(() => console.log("✅ PPT created successfully"))
  .catch(e => { console.error("❌ Error:", e); process.exit(1); });