Pathophysiology of Retinopathy of Prematurity

ROP:Risk Factors  Prematurity --- Gestational age: less than 34 weeks  Low Birth Weight: less than 2000 gm especially less than 1250gms  Oxygen therapy : Fluctuating oxygen saturation

Contd…  Other factors : Sepsis, Multiple blood transfusions, Multiple births, Hyaline membrane disease, Use of aminophylline, antibiotics, Apnoeic spells, Low pH

Pathophysiology  At 16 wks-Mesenchyme growth starts as precusrsor of blood vessels  Blood vessels reache Nasal ora by 36 wks and Temporal ora by 40 wks  High O2 obliterate newly formed capillaries, damaging endothelium.  Reduce blood flow due to vasoconstriction

Pathophysiology  Most of the time- no new vessel, normal vasculogenesis-regressed ROP(90%)  Neovascular proliferations- shunt cells break through ILM & grow in vitreous

Pathogenesis  PhaseI: 22 Wk to 30 PM wk. Relative Hyperoxia, decreased VEGF level. - Strategy: Prevention and Early treatment  Phase II : PM wk Relative hyperoxia, increased VEGF level. - Strategy: Treatment. Normal O2, normal VEGF, Normal Intra- uterine growth PhaseI, high 02, low VEGF Premature birth Stage 0, Stage1, Stage2 Stage3 Ph2, low 02, high VEGF StageV treatment

ETROP Criteria for Treatment Type I- ZoneI, Any stage,+ - ZoneI, Stage3, No + - Zone II, stage2 or 3, + Type II- Zone I, Stage1 or 2, No + - Zone II, Stage3, No + TREAT OBSERVE Early Treatment of Retinopathy of Prematurity Cooperative Group. Revised indications for the treatment of retinopathy of prematurity. Arch Ophthalmol 2003;121:

FVP Zone 1 any stage with +Zone II, Stage II + Zone II, Stage III +

 ROP ANIMATION mpeg ROP ANIMATION mpeg

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Rop Handout

Chasing dropouts  Maintain follow up schedule in Excel worksheet with reminders  ROP Cards updated at every visit with mention of next date of visit  Call parents in case of dropout -- At least 2 phone calls & noted the time & date. -- Registered letter  Call neonatologist

Priyamvada Birla Aravind Eye Hospital (Till 2014 NOVEMBER)  Total baby seen  Rop baby laser: eyes-278  Avastin-30  Rop surgery done-8  StageV, referred- 10  Total StageV, Blind & inoperable= 25

Stage 3, lasered