Retinopathy of PrematurityRetinopathy of Prematurity (ROP) (ROP)

(With acknowledgements to the Online Journal of Ophthalmology: www.onjoph.com)

ContentsContents IntroductionIntroduction EpidemiologyEpidemiology IncidenceIncidence Pathogenesis and clinical featuresPathogenesis and clinical features Classification of ROPClassification of ROP TerminologyTerminology Examination and screeningExamination and screening ManagementManagement ConclusionConclusion

IntroductionIntroduction

ROP ROP potentially blinding potentially blinding ICROP and CRYO-ROP – guidelines to screen, discuss ICROP and CRYO-ROP – guidelines to screen, discuss

and treat ROP.and treat ROP. ↑↑frequency of ROPfrequency of ROP 2 facets 2 facets Acute phaseAcute phase – normal vasculature goes awry – normal vasculature goes awry

abnormal vessel proliferation.abnormal vessel proliferation. Chronic phaseChronic phase – late proliferation, retinal detachment – late proliferation, retinal detachment

and visual loss due to cataracts; squints; amblyopia etc.and visual loss due to cataracts; squints; amblyopia etc. ** 90% acute ROP regress spontaneously. ** 90% acute ROP regress spontaneously.

EpidemiologyEpidemiology Cryo-ROP: Incidence and severity correlates Cryo-ROP: Incidence and severity correlates

with LBW and early post-conceptual with LBW and early post-conceptual gestational age.gestational age.

↑↑Incidence of more severe posterior ROP in Incidence of more severe posterior ROP in smaller and younger infants.smaller and younger infants.

Caucasians and Hispanics have ↑aggressive Caucasians and Hispanics have ↑aggressive ROP compared to African Americans.ROP compared to African Americans.

Mayet and Cockinos (CHBara) – There is a Mayet and Cockinos (CHBara) – There is a similar incidence of ROP in Africans compared similar incidence of ROP in Africans compared to other races but with less severity (3%).to other races but with less severity (3%).

IncidenceIncidence Related to gestational age (GA) and birth weight (bw).Related to gestational age (GA) and birth weight (bw). ROP rare in bw > 2000 grams.ROP rare in bw > 2000 grams. 70% ROP in bw < 1250g and 7% develop threshold 70% ROP in bw < 1250g and 7% develop threshold

ROP.ROP. Threshold ROP very rare in bw > 1250g. (Mayet & Threshold ROP very rare in bw > 1250g. (Mayet &

Cockinos)Cockinos) 95% ROP begins at 32-34 weeks GA.95% ROP begins at 32-34 weeks GA. Threshold disease at 36 weeks.Threshold disease at 36 weeks. Regression with spontaneous healing at 45-48 weeks Regression with spontaneous healing at 45-48 weeks

GA.GA. Long term ophthalmic follow up of formerly Long term ophthalmic follow up of formerly

premature neonates who suffered severe ROP.premature neonates who suffered severe ROP.

Pathogenesis and clinical Pathogenesis and clinical featuresfeatures

Incomplete retinal vascularisation.Incomplete retinal vascularisation.

Vessels migrate from disc to ora at 16 weeks.Vessels migrate from disc to ora at 16 weeks. Mature vessels extend to nasal ora at 36 weeks.Mature vessels extend to nasal ora at 36 weeks. Vessels extend to temporal ora at 39-41 weeks.Vessels extend to temporal ora at 39-41 weeks.

STOP-ROP : supplemental treatment of oxygen in STOP-ROP : supplemental treatment of oxygen in progression of ROP did not yield statistically significant progression of ROP did not yield statistically significant difference in the progression to threshold ROP.difference in the progression to threshold ROP.

LIGHT-ROP : Light reduction in ROP showed no role in LIGHT-ROP : Light reduction in ROP showed no role in the incidence or severity of ROP.the incidence or severity of ROP.

Pathogenesis Cont.Pathogenesis Cont.

Classification of ROPClassification of ROP International Classification of Retinopathy of International Classification of Retinopathy of

Prematurity (ICROP)Prematurity (ICROP) Describe ROP according to - Zone, Extent and Describe ROP according to - Zone, Extent and

Stage.Stage.

Classification of ROP cont.Classification of ROP cont. Staging:Staging:

5 stages - describe abnormal vascular response. 5 stages - describe abnormal vascular response. Most severe stage is used to determine the stage Most severe stage is used to determine the stage of the eye as whole.of the eye as whole.

Stage 1: Demarcation line Stage 2: Ridge

Classification of ROP cont.Classification of ROP cont. Stage 3: Extaretinal Stage 3: Extaretinal

Fibrovascular Fibrovascular ProliferationProliferation

Stage 4: Partial Stage 4: Partial Retinal Detachment Retinal Detachment

4a - Extrafoveal4a - Extrafoveal 4b – Foveal4b – Foveal Stage 5: Total Stage 5: Total

Retinal DetachmentRetinal Detachment

Classification of ROP cont.Classification of ROP cont. Plus disease – Plus disease – signs indicating signs indicating

severity. Venous severity. Venous dilatation or arteriolar dilatation or arteriolar tortuosity in at least tortuosity in at least two quadrants; vitreous two quadrants; vitreous haze; poor pupil haze; poor pupil dilatation; vascular dilatation; vascular engorgement of the engorgement of the iris.iris.

TerminologyTerminology Threshold disease : Stage 3 in zone 1 or 2 in at Threshold disease : Stage 3 in zone 1 or 2 in at

least 5 contiguous or 8 non-contiguous clock hours least 5 contiguous or 8 non-contiguous clock hours with plus disease. Point at which infant is treated.with plus disease. Point at which infant is treated.

Pre-threshold disease : ETROP. High and low risk Pre-threshold disease : ETROP. High and low risk prethreshold disease.prethreshold disease.

High risk prethreshold : High risk prethreshold : Zone1, any stage ROP with plus disease.Zone1, any stage ROP with plus disease. Zone 1, stage 3 with or without plus disease.Zone 1, stage 3 with or without plus disease. Zone 2, stage 2/3 with plus disease.Zone 2, stage 2/3 with plus disease. Rush disease : Rapid progressive severe form of Rush disease : Rapid progressive severe form of

ROP. Posterior location. Dilated, tortuous vessels ROP. Posterior location. Dilated, tortuous vessels with shunt vessels throughout retina.with shunt vessels throughout retina.

Examination and screeningExamination and screening Dilate with cyclomydril.Dilate with cyclomydril. Screening guidelines vary depending on resources, Screening guidelines vary depending on resources,

financial implications and medicolegal liability.financial implications and medicolegal liability. Universal criteria for screening :Universal criteria for screening : 1. Infants with bw < 1500g or GA < 31 weeks.1. Infants with bw < 1500g or GA < 31 weeks. 2. First examination 4/52 after birth.2. First examination 4/52 after birth. 3. Examine 1 or 2 weekly depending on stage of 3. Examine 1 or 2 weekly depending on stage of disease at initial visit.disease at initial visit. 4. Treat threshold disease.4. Treat threshold disease. 5. Examine until 45 weeks GA without threshold 5. Examine until 45 weeks GA without threshold

disease disease or till vascularisation reaches zone 3.or till vascularisation reaches zone 3.

ManagementManagement ETROP & Cryo-ROPETROP & Cryo-ROP Treat threshold disease as it decreases unfavourable outcome Treat threshold disease as it decreases unfavourable outcome

from 15 to 9%.from 15 to 9%. Ablation is beneficial for prethreshold ROP.Ablation is beneficial for prethreshold ROP. Photograph screening for ROPPhotograph screening for ROP Telemedicine with on-site treatment.Telemedicine with on-site treatment. Evidence based screening criteriaEvidence based screening criteria Screen at 31 weeks GA or 4 weeks chronologic age if born before Screen at 31 weeks GA or 4 weeks chronologic age if born before

27 weeks.27 weeks. Continue screening till 45 weeks GA or vascularisation in zone 3.Continue screening till 45 weeks GA or vascularisation in zone 3. Screening of 1250g-1800g infants is cost effective.Screening of 1250g-1800g infants is cost effective. ETROP : Recognize prethreshold disease and follow up 2 weekly.ETROP : Recognize prethreshold disease and follow up 2 weekly. Follow up weekly if zone 2, stage 2 ROP or if Follow up weekly if zone 2, stage 2 ROP or if vascularisation ends in zone 1.vascularisation ends in zone 1.

Management Cont.Management Cont. Treatment of ROPTreatment of ROP Portable indirect laser units. Laser superior to cryotherapy.Portable indirect laser units. Laser superior to cryotherapy. Rush diseaseRush disease Poor prognosis if found in zone 1. 64% anterior zone 1 required Poor prognosis if found in zone 1. 64% anterior zone 1 required

surgery after laser. 100% posterior zone 1 required surgery after surgery after laser. 100% posterior zone 1 required surgery after laser treatment.laser treatment.

ROP related retinal detachmentROP related retinal detachment * misconceptions * misconceptions 1. Stage 4A = benign and can wait till stage 4B before treating.1. Stage 4A = benign and can wait till stage 4B before treating. 2. Poor prognosis with total detachment.2. Poor prognosis with total detachment. Surgery reserved for stages 4A, 4B and 5.Surgery reserved for stages 4A, 4B and 5. Intravitreal triamcinolone in Stage 5Intravitreal triamcinolone in Stage 5 reattachment success reattachment success

rate.rate. Vision restoration technology – future.Vision restoration technology – future.

ConclusionConclusion Ultimate prevention = prevent premature births.Ultimate prevention = prevent premature births. The role of VEGF and IGF-1 may lead to pharmacologic The role of VEGF and IGF-1 may lead to pharmacologic

interventions in preventing progression.interventions in preventing progression. Evidence based data reshape our understanding of who Evidence based data reshape our understanding of who

to screen and determines the critical timing of to screen and determines the critical timing of treatment.treatment.

Digital fundus imaging may revolutionalise screening.Digital fundus imaging may revolutionalise screening. ROP is a lifelong disease with sequelae manifesting into ROP is a lifelong disease with sequelae manifesting into

the 2the 2ndnd decade. decade. Surgical intervention preserves vision in ROP-related Surgical intervention preserves vision in ROP-related

retinal detachment esp. before macular detachment.retinal detachment esp. before macular detachment.