Objective To explore the effect of oxygen inhalation on the retinae of newborn rats and its mechanism.Methods We mimicked the retinopathy of prematurity(ROP) by putting the newborn rats in high concentrated oxygen. One-day old rats were put into the oxygen box with the oxygen concentration of 80% for continuous 7 days; then in air condition for 7 days. The arterial blood oxygen pressure, retinal superoxide dismutase (SOD), and malondialdehyde (MDA) of the rats (1,2,4,7,8,9,11,14 days old) were examined. The diameter of retinal vessels′main branch and the coverage rate of peripheral vessels were measured in 7- and 14-day-old rats by ink perfusion. The retinal neovascularization of rats (8,9,11, 14 days old) were observed by HE staining. The rats of the same age fed in air condition were in the control group.Results The differential pressures of blood oxygen of rats (1,2,4,7 days old) in study group were significantly higher than those in the control group (P<0.01), while the differential pressures of blood oxygen of rats (8,9,11,14 days old) in study group were lower than those in the control group (P>0.05). The contents of SOD of the retinae in the rats ( 1,2,4,7,8 days old) were significantly lower than those in the control group(P<0.01, P<0.05 ), while the contents of MDA were significantly higher than those in the control group (P<0.01,P<0.05). The diameter of retinal vessels′main branch in 7-day rats was 75% of the control group, and the coverage rate of peripheral vessels was 22% of the control group; and was 61% and 73% respectively in 14-day-old rats. The neovascularization could be seen in 16.7% of the rats in the study group and nought in the control group.Conclusion The damage of free radical of the retina in high concentrated oxygen and hypoxia situation after oxygen supply may be one of the most important mechanism of ROP. (Chin J Ocul Fundus Dis,2003,19:269-332)
ObjectiveTo analysis the fundus characteristics of fundus fluorescein angiography (FFA) of retinopathy of prematurity (ROP). MethodsEighty-four cases (168 eyes) who were diagnosed with ROP by a binocular indirect ophthalmoscope were included in the study. Among the 84 cases, there were 2 cases (4 eyes) of stage 1 ROP, 26 cases (52 eyes) of stage 2 ROP, 40 cases (80 eyes) of stage 3 ROP, 4 cases (8 eyes) of stage 4 ROP, and 4 cases (8 eyes) of stage 5 ROP, 9 cases (18 eyes) of plus disease, 8 cases (16 eyes) of aggressive posterior ROP (APROP). All infants received FFA with RetCam Ⅱ under general anesthesia and mydriasis. The retinal vein morphology, capillary filling state, neovascularization morphology and fluorescein leakage were observed. ResultsFFA revealed increased branching, expansion and tortuous peripheral retinal capillaries, increased capillary permeability with a small amount of fluorescein leakage in stage 1 ROP. There was a clear dividing line between the vascular area and the remote avascular area. In stage 2, the peripheral branches of temporal retinal blood vessels increased, and parallel distributed like a broom. The capillary end anastomosed with each other to form a loop. The fibrous tissues at the lesion edge proliferated as a ridge, with popcorn phenomenon. In stage 3, the ridge continued broadening, and the neovascular fibrous membrane formed breakthrough internal limiting membrane, stretched into the vitreous with a lot of fluorescein leakage. The ridge and remote avascular zone demarcated clearly. In stage 4 and 5, the vessel changes had similar phenomenon with the stage 2 and 3 in undetached retina, but the vessels in the detached retina expanded with fluorescein leakage. As for plus disease, the retinal arterioles in the posterior pole were tortuous, there were a large number of non-perfusion area in the peripheral retina with hemorrhage and obscured fluorescence. The retinal vessels in posterior pole in AP-ROP were also tortuous, and the capillaries were extreme expanded, while there were very few tortuous vessels and no capillary formation in the other part of retina.At the avascular zone boundaries, there were a large group of neovascularization with fluorescein leakage. ConclusionsThe demarcation line separating the avascular from the vascularized retinal regions is formed in stage 1, 2 and 3, and the amount of fluorescein leakage gradually increase from stage 1 to stage 3 ROP. The detached retina of stage 4 and stage 5 has an unclear focal length in the FFA. The plus disease mainly has arteriolar tortuosity in the posterior pole retina. In the AP-ROP cases, both of the arterioles and venules in posterior pole of retina are tortuous and expanding with neovascularization leakage of fluorescein.
Objective To determine the effect of methimazole (MMI) on retinal vascular development in neonatal rats, and to investigate the relationship between the concentration of insulin-like growth factor-I (IGF-I) in serum and the development of normal blood vessels and between the concentration of IGF-I and the formation of abnormal blood vessels. Methods There were 75 neonatal SpragueDawley rats in experimental group whose mothers were raised with water with 0.1% MMI at the first day of parturition. Another 50 neonatal rats were in the control group whose mothers were raised with normal water. The rats in the two groups were sub-divided into 4day and 10day subgroup, respectively. The retinal flatmount of the right eyes were stained with adenosine diphosphatase (ADPase); with the paraffin section of the left eyes, the number of nucleolus breaking through retinal inner limiting membrane was counted and the retinal blood vessels were evaluated. Serum IGF-I levels were detected by radioimmunoassay, and the weight of the neonatal rats in each group were observed and recorded. Results The incidence of retinal neovascularization in 10 day MMI group was 27%, and 0% in 4-day MMI group and control group. The serum IGF-I level in 4-day and 10-day MMI group (73.07 ng/ml, 175.13 ng/ml) was obviously lower than which in the 4-day and 10-day control group (168.73 ng/ml,306.38 ng/ml) (P=0.00). Obvious slow growth of the neonatal rats was found in MMI group compared with which in the control group. Conculsions MMI may inhibit the normal growth of retinal blood vessels and lead neovascularization, which may relate to the initial decrease of the serum IGF-I level. (Chin J Ocul Fundus Dis, 2007, 23: 198-201)
ObjectiveTo observe the therapeutic effect of segmental scleral buckling and vitrectomy with/without lensectomy on the retinopathy of prematurity (ROP) stage 4a, 4b and 5. MethodsOne hundred and thirty-four ROP infants (181 eyes) diagnosed as stage 4a, 4b and 5, and performed with segmental scleral buckling or vitreous with/without lensectomy were retrospectively analyzed. The operated 4a-, 4b- and 5- stage eyes were 40, 51 and 90 eyes. The operational method depended on the location and severity of fibrovascular membrane. Of 181 eyes, segmental scleral buckling was referred for 37 eyes which include 23 eyes with 4a stage and 14 eyes with 4b stage; vitrectomy was referred for 50 eyes which include 14 eyes with 4a stage, 29 eyes with 4b stage and 7 eyes with 5 stage; vitrectomy with lensectomy was referred for 94 eyes which include 3 eyes with 4a stage, 8 eyes with 4b stage and 83 eyes with 5 stage. The effect was classified as success, improved and failure. Failure includes lost eye. Follow-up for 4a, 4b and 5 stage patients are 34, 31 and 29 months respectively. ResultsSegmental scleral buckling was referred for 37 eyes, success in 23 eyes (62.16%), improved in 11 eyes (29.73%), failure in 3 eyes (8.11%). Vitrectomy was referred for 50 eyes, and success in 20 eyes (40.00%), improved in 22 eyes (44.00%), and failure in 8 eyes (16.00%). In the total of 94 eyes underwent vitrectomy with lensectomy, 20 eyes was success (21.28%), improved in 17 eyes (18.08%), failure in 57 eyes (60.64%). In 40 stage 4a eyes, 33 successes (82.50%), 6 improved (15.00%) and 1 failure (2.50%). In 51 stage 4b eyes, 11 successes (21.57%), 30 improved (58.82%) and 10 failures (19.61%). For 90 stage 5 eyes, 14 successes (17.50%), 19 improved (23.75%) and 57 failures (71.25%). The therapeutic effect of segmental scleral buckling for stage 4a was better than that for stage 5 (χ2=6.707,P=0.035). The difference of therapeutic effect of vitrectomy for different stage was significant (χ2=21.010,P=0.000); stage 4a was the best; stage 4b was the second, stage 5 was the worst. The therapeutic effect of vitrectomy with lensectomy for stage 5 was worse than that for stage 4a and 4b (χ2=16.066,P=0.003). ConclusionThe surgery patterns of ROP was determined based on the disease severity, the surgery effects of stage 4a and 4b were better than stage 5, which had nothing to do with the surgical procedures.
ObjectiveTo evaluate the efficacy and safety of intravitreal ranibizumab (IVR) for the treatment of retinopathy of prematurity(ROP). MethodsA total of 57 eyes of 29 premature infants with diagnosis of high-risk pre-threshold, threshold ROP, or aggressive posterior ROP were reviewed and analyzed in the study. The lesions of 18 eyes were located in zoneⅠ, 39 eyes were located in zoneⅡ. All infants in the study received IVR (10 mg/ml, 0.025 ml) as the initial treatment within 24 hours after diagnosis. Follow-up examinations were performed after treatment, every week at the first month, every 2 weeks at the second and third month, every month afterward, until vascularization of zoneⅢwas observed. Follow-up ranged from 16 weeks to 52 weeks, and the average follow-up time was (28.1±11.7) weeks. If the infants didn't respond positively to the treatment or the disease recurred, the additional treatments were applied. 36 eyes (63.2%) received a single injection, whereas 21 eyes (36.8%) received additional treatments. The follow-up examinations included the development of retinal vessels, the ocular or systemic adverse events. ResultsAmong the eyes, the development of peripheral retinal vessels could be observed in 36 eyes (63.2%) which received a single injection; clinical improvement in 11 eye (19.3%) which received repeat injection; stable disease in 10 eyes (17.5%) which received laser therapy. Among the eyes, 18 eyes (31.6%) recurred, including ggressive posterior ROP (14 eyes), threshold ROP (2 eyes) and high-risk pre-threshold ROP (2 eyes). The mean time of recurrence was (5.7±2.1) weeks (range 2.0-8.0 weeks). Three eyes (5.3%) of high-risk pre-threshold, threshold ROP lacked a positive response to the treatment. The lesions were controlled after additional laser given in these eyes. No serious ocular or systemic adverse events associated with the drug or the injection was observed during the follow-up period. ConclusionIVR is safe and effective for most ROP infants. In cases of recurrence or no response, conventional laser treatment or an additional IVR injection were needed.
Objective To determine the incidence of and risk fact ors for retino pathy of prematurity (ROP) among preterm infants in Beijing after implementation of the ROP guidelines. Methods The preterm infants with birth weight le; 2000 g or gestational age le; 3 4 weeks who were admitted to the neonatal intensive care units in 6 hospitals in Beijing from Jan. 1, 2005 to Dec. 31, 2005 were screened. Ophthalmologic examin ations started 3-4 weeks after birth and ROP was classified by the revised Inte r national Classification. Maternal and perinatal risk factors of occurrence of R OP were analyzed. Results In the 639 infants who had been scre ened in the 6 ho spitals, ROP was detected in 69 (10.8%), in whom 23 infants (39 eyes) (3.6%) had type 1 ROP and underwent photocoagulation. The lower the birth weight and small er the gestational age was, the higher the incidence of ROP was. Logistic regres sion analysis indicated that low birth weight, apnea gt;20 seconds, anemia, hypoxic-ischemic encephalopathy and placenta abruption were the high risk factor of R O P.Conclusion In Beijing the incidence of ROP is 10.8% after i mplementation of the ROP guidelines. Low birth weight, apnea gt;20 seconds, anemia, hypoxicischem ic encephalopathy and placenta abruption were the high risk factor of ROP.
ObjectiveTo retrospectively analyze incidence and trends of retinopathy of prematurity (ROP) from 2004 to 2013 in Shenzhen. MethodsA total of 9100 preterm children (5401 males, 3699 females) were screened for ROP in Shenzhen from January 2004 to June 2013 using binocular ophthalmoscope or RetCam Ⅱ. First examination was performed from 4-6 weeks after birth. The birth weight was 520-2990 g with an average of (1710±410) g.The gestational age were 24-36 weeks with an average of (31.57±1.99) weeks. The gestational age of 208 children were <28 weeks, 3608 children were 28-32 weeks, 3553 children was 33-34 weeks, 1731 children was >34 weeks. The ocular findings were recorded according to the International Classification of ROP and The Early Treatment for ROP. Only the more aggressive eye of bilateral asymmetrical cases was counted for statistical purpose, and the cases required surgeries were defined as severe cases. The 10 years period was divided into first phase (2004-2008) and second phase (2009-2013). The incidence of ROP and severe ROP of these two phases was compared and statistics was analyzed. ResultsIn the past 10 years, the overall incidence of ROP and sever ROP in Shenzhen was 12.49% and 4.99% in this screen. The children were divided into 4 groups according to the birth weight, the ROP incidences of birth weight <1000 g, 1000-1499 g, 1500-1999 g and ≥2000 g were 62.62%, 28.40%, 11.34% and 3.63% respectively. The severe ROP incidences were 34.95%, 12.21%, 3.73% and 0.49% respectively in these birth weight groups. The children were divided into 4 groups according to gestational weeks, the ROP incidences of gestational age <28 weeks, 28-32 weeks, 33-34 weeks and >34 weeks were 67.31%, 25.27%, 7.22% and 3.87% respectively. Severe ROP incidences were 37.02%, 10.71%, 1.79% and 0.68% in these gestational age groups respectively. ROP and severe ROP incidences were decreased from 14.64% at first phase to 11.47% at second phase, and from 6.52% at first phase to 4.26% second phase respectively, the differences were statistical significant (χ2=26.96, 26.61; P<0.05). ROP and severe ROP incidence in <1000 g birth weight group at second phase were much less than the first phase (χ2=13.676, 5.271; P<0.05). In <28 weeks gestational age group, the ROP incidence was the same in first phase and second phase (χ2=0.843, P>0.05), but the severe ROP incidence at second phase was much less the first phase (χ2=4.757,P<0.05). ConclusionFrom 2004 to 2013, the incidences of ROP and severe ROP have decreased significantly in Shenzhen.
Objective To observe the characteristics of morphological development of premature retina at 33-46 weeks of gestational corrected age (GCA). Methods A total of 268 premature infants were divided into 7 groups according to the GCA (33-34,35-36,37-38,39-40,41-42,43-44 and 45-46 weeks). The ocular fundus of those infants were recorded and analyzed by an indirect ophthalmoscopelinked imaging system. Results As GCA increases, noticeable macular morphological changes occurred and recorded in 96% of infant at 45-46 weeks of GCA. Retinas were gradually vascularized at 41-42 weeks (nasal retina) or 43-44 weeks (area Ⅲ,temporal retina), and pigmented in 84% of infant at 45-46 weeks of GCA. Conclusion Macular morphological patterns, retinal blood vessels and pigments continue to develop in postnatal premature infants.
In the expert consensus published by the Pediatrics in 2013, it was first proposed that anti-VEGF drugs can be considered for retinopathy of prematurity (ROP) with stage 3, zone Ⅰ with plus disease. However, there are many problems worth the attention of ophthalmologists, including the advantages and disadvantages of anti-VEGF therapy compared with traditional laser therapy, systemic and ocular complications after anti-VEGF therapy, and what indicators are the end points of anti-VEGF therapy. Combined with this consensus and numerous research findings, we recommend that the first treatment for anti-VEGF or laser therapy should be considered from disease control effects. For the threshold and pre-threshold lesions, the effect of anti-VEGF therapy for zoneⅡ lesions is better than that for zone Ⅰ lesions and the single-time effective rate is high. So, it is suggested that anti-VEGF therapy should be preferred for the first treatment. The choice of repeat treatment should be considered from the final retinal structure and functional prognosis. Laser therapy is advisable for the abnormal vascular regression slower and abnormalities in the posterior pole. It can reduce the number of reexaminations and prolong the interval between re-examinations. However, the premature use of laser has an inevitable effect on peripheral vision field. Excluding the above problems, supplemental therapy can still choose anti-VEGF therapy again. Most of the children with twice anti-VEGF therapy are sufficient to control the disease. Anti-VEGF therapy should be terminated when there are signs such as plus regression, threshold or pre-threshold lesions controlled without recurrence, peripheral vascularization, etc.
ObjectiveTo observe the effect of retinal hemorrhage on the treatment of retinopathy of prematurity (ROP) by laser photocoagulation.MethodsRetrospective case analysis. Screening and diagnosis of 134 eyes in 67 patients with ROP in Zone Ⅱ Stage 3+ were included in the study. Among them, 32 patients were male and 35 patients were female. The average birth gestational age was 27.80±2.55 weeks. The average birth weight was 1060±320 g. All children underwent binocular indirect ophthalmoscopy and RetCam Ⅲ. Of the 134 eyes, 38 eyes (28%) with anterior, ridge or vitreous hemorrhage (group A); 96 eyes (72%) without hemorrhage. Retinal avascular photocoagulation was performed within 72 hours after diagnosis by intravenous sedative combined with ocular surface anesthesia with 810 nm laser. Follow-up was performed at 1, 4, 8 and 12 weeks after treatment, and then every 6 months thereafter. The same equipment and methods before treatment were used to examine and document the regression and progression of ROP. The number of eyes with lesions after photocoagulation in the two groups was compared by χ2 test. The t-test was used to compare the gestational age and birth weight.ResultsAmong 134 eyes, lesions completely resolved in 125 eyes (93.3%), progressed in 9 eyes (6.7%). In group A, 7 eyes were progressive (18.4%). In group B, 2 eyes were progressive (2.1%). There was a statistically significant difference in the number of eyes with lesions after laser treatment in group A and B (χ2=9.14, P=0.003). There was no significant difference in birth gestational age and birth weight (t=0.85, 0.25; P=0.40, 0.80).ConclusionThe laser photocoagulation is safe and effective in the treatment of ROP. The preretinal, ridge or vitreous hemorrhage is related to the progression of the lesion after laser photocoagulation.