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infants with aggressive posterior retinopathy of prematurity ( aprop ) and specific clinical profiles are likely to progress despite laser treatment.1 in these patients , frequent follow - up ( every 34 days ) after laser photocoagulation ( lp ) is imperative . additionally , timely vitreous surgery on the development of a retinal detachment is essential .
this case report presents the progression and management of a premature infant with aprop with a protracted clinical course .
an female infant was referred to our tertiary care ophthalmology center , 9 weeks after birth on detection of retinopathy of prematurity ( rop ) by the local ophthalmologist . the birth weight was 700 g and gestational age was 2628 weeks .
the infant had been admitted to a neonatal intensive care unit ( nicu ) due to multiple risk factors including respiratory distress syndrome , sepsis and neonatal jaundice . at presentation
, she weighed 1400 g. the anterior segment showed neovascularization of the iris , poorly dilating pupils and significant tunica vasculosa lentis .
the posterior segment was evaluated using the binocular indirect ophthalmoscope and documented with the retcam imaging system ( clarity medical systems , usa ) .
the patient had bilateral aprop with a few preretinal hemorrhages with plus disease.2 the presence of a ridge with new vessels elsewhere ( nve ) that had bled in the right eye qualified this as  hybrid  zone 1 disease [ figure 1].3 parents were exhaustively counseled and consent obtained for lp .
retcam images at presentation showing hybrid form of retinopathy of prematurity , zone 1 disease in the right eye , aggressive posterior retinopathy of prematurity in the left eye .
arrows show flat neovascularization laser photocoagulation was performed with the double frequency yttrium - aluminum - garnet laser of wavelength 532 nm with an indirect ophthalmoscope delivery system with a spot size of 500 microns ( iridex oculight tx ; iridex corporation , usa ) .
the laser parameters were as follows right eye 2981 shots and left eye 2611 shots with energy of 90110 mw , each shot duration being 100 ms .
pigmented eyes of indian infants have a higher uptake of laser energy.4 the extensive lp bilaterally was punctuated by spells of bradycardia .
the bradycardia , poorly dilating pupils and tunica vasculosa lentis may interfere with complete treatment .
ten days after the initial lp , additional lp was performed to cover the areas inside the vascular loops ( right 846 shots / left 346 shots ) .
few elevated fibrovascular proliferative bands were seen though the nves were regressing [ figure 2 ] .
image quality affected in left eye due to tunica vasculosa lentis eleven days after the additional laser , deterioration of both eyes was noted .
the aprop had progressed to stage 4 rop showing the tractional retinal detachment , vitreous bleed and recurrence of the plus disease [ figure 3].2 the patient underwent surgery and had to be given packed red blood cells as the hemoglobin was only 7 g / dl .
the patient received intravitreal bevacizumab ( ivb ) ( 0.625 mg i.e. 0.025 ml ) in the right eye followed 4 days later by lens sparing vitrectomy ( lsv ) .
intravitreal bevacizumab was injected in the left eye at the end surgery in the right eye .
this was followed by left eye lsv , a few days later as depicted in table 1 .
three port pars plana vitrectomy was performed by standard technique described by trese et al.5 progression of aggressive posterior retinopathy of prematurity with vitreous bleed , stage 4a ( right eye 3 , right eye 3 ) and nasal tractional retinal detachment ( left eye3 ) time frame of treatment postoperatively , the patient was meticulously followed - up for over 10 months after the 2 surgery that included assessment for visual acuity and retinal status .
total regression of the retinopathy was noted postoperatively with complete resolution of vitreoretinal traction bilaterally [ figure 4 ] . at 46 weeks
follow - up at a postmenstrual age of 300 days , the baby had central , steady and maintain fixation in both eyes with a visual acuity of 4.7 cpd ( cycles per degree ) @ 55 cm in each eye and 9.6 cpd @ 55 cm binocularly . no resistance to unilateral occlusion was noted .
in this case , the right eye showed the hybrid form of rop demonstrating both ridge tissue ( simulating staged rop ) and flat neovascularization simulating aprop in the same eye.3 infants < 1000 g should be screened within 20 after birth .
this is a cardinal rule that was not followed by the referring nicu in this case.6 preterm , very low birth weight infants with multiple risk factors can be challenging to manage.1 progression of retinopathy can occur despite adequate lp.17 in fact , aprop is known to progress directly to retinal detachment.2 in patients with aprop , recognizing the unique high risk characteristics such as gestational age < 29.5 weeks , zone 1 disease , presence of preretinal hemorrhages prior to laser therapy , and appearance of de novo fibrovascular proliferation after laser is as essential as is strict daily follow - up and aggressive surgical intervention to ensure good visual outcomes.1 studies have reported extremely high levels of vascular endothelial growth factor ( vegf ) in rop as compared to other retinal vascular diseases.8 lp does not neutralize the vegf that is already produced but prevents further production of vegf .
however , a is a relatively long interval in the natural course of rop.7 the patient received bevacizumab a few days prior to surgery to neutralize the vegf and decrease the chances of intra- and postoperative bleeding .
a few centers advocate use of bevacizumab as initial therapy for aprop.9 we treat aprop with lp , with remains the gold standard , due unaddressed long - term safety concerns associated with ivb treatment . at our center , ivb is reserved as a rescue therapy for cases with small pupils , rubeosis ( where laser is impossible , as primary treatment ) or for ablated nonregressing aprop as a secondary treatment . in this case ,
marked deterioration of similar cases is known to occur within a couple of days.1 without frequent follow - up , the progression ( despite treatment ) of the disease would have been missed . if follow - up is every 23 months cases often return with stage 5 rop despite adequate laser treatment . the role of lsv to relieve vitreoretinal traction in such cases
can not be overemphasized.510 the surgical intervention prior to detachment of the macula was a significant prognostic factor for visual recovery.510 our case illustrates that infants with aprop and with similar ( specific ) clinical profiles are likely to progress despite laser treatment.1 frequent follow - up , every 34 days , is warranted for these cases .
decisive and timely vitreous surgery on the development of a retinal detachment is the key to good anatomical and visual outcomes . in high - risk infants similar to this case
the management of retinopathy of prematurity ( rop ) can be challenging in preterm babies with a gestational age < 30 weeks , those with very low birth weight and multiple risk factors ( eg . , oxygen therapy for respiratory distress , sepsis , neonatal jaundice ) . a premature infant presented with  hybrid 
  zone 1 disease in the right eye and aggressive posterior rop in the left eye . 
 both eyes were adequately treated with laser photocoagulation ; however , the eyes deteriorated and progressed to stage 4 rop . 
 both eyes eventually underwent intravitreal bevacizumab followed by lens sparing vitrectomy with good anatomical and visual outcome . 
 anticipation of progression despite laser photocoagulation in certain clinical scenarios , frequent follow - up and timely surgical intervention is paramount .