GENETICS MasterGene in developmentof Eye PAX G t PAX 6 gene mutation PaisedBox 6gene t Coloboma Microphthalmia PetersAnomaly Generesponsible forDivision of Eyefield into 2eyeGlobes SHH Soni'T Hedgehog
PAX6 expression PAX G switch for eye development
DD
Holo Prose NCEPHALY Defect in SHH Gene Proboscis Cyclopean Eye fSynophthalmia7 ANOPHTHALMIA failure offormation of opticVesicle to attain e any visibleglobestructure
MICROPHTHALMIA to simple_Pure Complex Nanophtralmos f t Structurally eyeball Associated features short Axial length of Dysgenesis eg.co oboma orbital cyst Bllolobomas Orbital cyst
COLO BOMA Mutilation PAX 6 gene mutation Chtoidal fissure hot closed Normally closes 1 by 7th week Coloboma t H Isis Retinae opticDisc ciliary choroid Body Recoloboma x ยต 2onules ODpit Axial Coloboma of OD MORNING Glory SYNDROME M.c.sie Inkronasalheyhole defect of iris Typical Coloboma
Hq Calamitouslens keyholedefectinin's I ymissingzonules 2ondaddoboma Types I It Typical Atypical Inferonasal quadrant otherareas macular'Toloboma siteof choroidalfissure closure is also atypical Atrial Complete E Incomplete fulllhickness Partialthickness defect defectof epithelium stroma
Retinochoroidal Globo ma r Retinalvessels dip down Excavated area yo RPE Choroid Exposing bare sclera Edges dean cut
Histopathology SplitinNeurosensory Retina Inner Nyagkey ppenfierarm a Layer ignerlayer Intercalary membrane 7 t.TT sFsRPElchaoid outerlayer fusey.si RPE Disorganised mass Termination of choroid H Junction Locus Minoris Resistentiae
Pathophysiology Defective fetalfissure closure t Inner Layerof opticCup growsfaster than outerLayer future RP E f Eversion 11 Gradual displacement of RPE t DoubleLayer of photoreceptors facing each other Absent RPE 1 Absent choroid
Ida Mann Classification AboveDisc superiorbogda Belowdisc Nimue area of Retina b n OD Globoma
Isolationism J so pigmendfoftwbana extreme
Lingam Gopal Classification of RC Globoma 19967 I NO Disc OD is outside fundus coloboma I Abnormal Disco I Colobomalous Disc isolated I Disc OD is within Fundus coloboma I ColobomatousDisc 4 I Disc shape not identified Blood vessels emanatingfrom superior aspectoflarge fundalwlobom
LingamGopal Classification r I I o E x I f f I abnormal TI r I I I I TI High myopia Good Visual Acuity III Microphthalmos common
OD Coloboma focalglistening while bowelshaped excavation Inferior NRR Absent1 Thin Assoc OD pit
Association of Hoboma Rhegmatogenous RD I 401 CHARGE syndrome CHD7 gene involved Edoboma HeartDefects Atresiachoanae Retardedgrowth Genital hypoplasia Ear malformation AICARDI syndrome WARBURGsyndrome
Note Lens Coloboma Misnomer CB coloboma I Absence ofwhales 1 Indented Lens
BIG PICTURE Efm orbit migratingNYids sypienophab SarkEctoderm 1 i II mean Lens NTeuralabe ftp7Iweloph.g Hyaloidvessels Neuroectoderm Future Retina Neuroectoderm Neural crest Mesenchyme surface Ectoderm mesodermal Mesenchyme
SUMMARY Go throughagain
Summary of the derivatives been Repeated to have the final understanding of the Big Picture
References
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