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Threshold retinopathy of prematurity: ocular changes and sequelae following cryotherapy
M R Dogra1, S Narang, C Biswas
1Department of Ophthalmology, Post Graduate Institute of Medical Education and Research, Chandigarh, India. eyepgi@ch1.dot.net.in
Insights
Cryotherapy for threshold retinopathy of prematurity (ROP) can lead to ocular changes like vessel tortuosity and myopia. Premature infants require long-term follow-up to monitor these potential ROP sequelae.
Area of Science:
- Ophthalmology
- Neonatology
- Pediatric Medicine
Background:
- Retinopathy of prematurity (ROP) is a significant cause of visual impairment in premature infants.
- Cryotherapy is a common treatment for threshold ROP, but its long-term ocular sequelae require investigation.
Purpose of the Study:
- To evaluate ocular changes and their sequelae after cryotherapy for threshold retinopathy of prematurity.
- To identify risk factors associated with these post-cryotherapy ocular findings.
Main Methods:
- Retrospective study of 49 eyes from 26 premature infants treated with cryotherapy for threshold ROP.
- Follow-up examinations included visual axis assessment, fixation pattern, anterior segment evaluation, cycloplegic refraction, and dilated fundus examination.
- Average follow-up duration was 28 months post-cryotherapy.
Main Results:
- Common retinal residuae included vessel tortuosity (65.3%), narrow temporal arcade (44.89%), and temporal crescent (34.69%).
- Ocular sequelae observed were myopia (40.82%) and strabismus (19.23%).
- Greater ROP involvement (clock hours) and higher gestational age were significant risk factors for ocular changes.
Conclusions:
- Cryotherapy for threshold ROP can result in various retinal and refractive changes.
- Premature infants treated for ROP require ongoing, long-term monitoring for ocular complications.
- Regular follow-up is crucial for detecting and managing refractive errors and motility disorders.
Purpose:
To determine ocular changes and sequelae following cryotherapy for threshold retinopathy of prematurity (ROP).
Methods:
This is a retrospective study of 49 eyes of 26 premature babies with threshold ROP treated with cryotherapy between 1995 and 1998. All eyes included in the study had favourable structural outcome after cryotherapy. Follow-up examination of all babies was done 12 - 62 months (average 28 months) after cryotherapy. Visual axis, fixation pattern, anterior segment examination, cycloplegic refraction and dilated fundus examination with indirect ophthalmoscopy were undertaken in all eyes during follow-up.
Results:
Posterior pole retinal residuae observed following cryotherapy were tortousity of blood vessels in 32 (65.3%), narrow temporal arcade in 22 (44.89%), temporal crescent in 17 (34.69%), disc drag in 13 (26.53%) and macular heterotopia in 7 (14.28%) eyes. Myopia was observed in 20 (40.82%) eyes and strabismus in 5 (19.23%) babies. The significant risk factor for ocular changes was ROP with more clock hours of involvement (p < 0.05). Higher period of gestation was associated with posterior pole changes (p< 0.05).
Conclusions:
All premature babies with threshold ROP treated with cryotherapy require frequent and long-term follow up to look for retinal residuae, refractive status, and ocular motility disorders.
