Retinopathy of prematurity

Retinopathy of Prematurity: Pathogenesis and Current Treatment Options

Retinopathy of prematurity (ROP) is a vasoproliferative retinal disorder that continues to be the major cause of preventable childhood blindness worldwide. Its incidence is inversely proportional to gestational age and birth weight. Approximately 65 percent of neonates with <1,250 g birth weight and 80 percent of those with 1,000 g birth weight will develop some degree of ROP. ROP can cause mild retinal disease without major visual defects or can adversely progress to retinal detachment and blindness through aggressive vascular proliferation. The purpose of this article is to raise awareness about the history of ROP, pathogenesis, normal retinal vascular development, international classification of ROP, and risk factors. Conventional ROP treatment and the promising antivascular endothelial growth factor monotherapy will also be explored.

Neuroprotective effect of Myo/Nog cells in the stressed retina

Myo/Nog cells are essential for eye development in the chick embryo and respond to injury in adult tissues. These cells express mRNA for the skeletal muscle specific transcription factor MyoD, the bone morphogenetic protein (BMP) inhibitor Noggin and the cell surface protein recognized by the G8 monoclonal antibody (mAb). In this study, we determined that Myo/Nog cells are present in low numbers in the retina of the mouse eye. G8-positive Myo/Nog cells were distinguished from neuronal, Müller and microglial cells that were identified with antibodies to calretinin, Chx10, glial fibrillary acidic protein and ionized calcium binding adaptor molecule 1, respectively. In the neonatal retina, the number of Myo/Nog cells increased in parallel with cell death induced by transient exposure to hyperoxia. In this model of retinopathy of prematurity, depletion of Myo/Nog cells by intravitreal injection of the G8 mAb and complement increased cell death. These findings demonstrate that Myo/Nog cells are a distinct population of cells, not previously described in the retina, which increases in response to retinal damage and mitigate hypoxia-induced cell death.

Retinopathy of prematurity in extremely low birth weight infants in Turkey

PURPOSE

This study was designed to determine the incidence rate of retinopathy of prematurity (ROP) in extremely low birth weight (ELBW) infants in the middle Black Sea region of Turkey.

METHODS

The charts of 1,719 preterm infants were reviewed between January 2003 and September 2011. Of them, 225 (13.1%) infants with birth weights of less than 1,000 g were enrolled in the study. ROP was classified according to the international classification of retinopathy.

RESULTS

Of the 225 ELBW infants, 47.6% had advanced ROP, 23.1% had mild ROP, and 29.3% did not have ROP; 30.2% infants required treatment. ROP was detected in 75.6% of multiple births versus 69.6% of singleton births; there were no significant differences between the two groups (P = .388).

CONCLUSION

Extremely premature infants with low gestational ages had high incidence rates of advanced ROP. Most ELBW infants require ROP treatment. In addition, increased survival of ELBW infants owing to advancements in neonatal care warrants the specialization of ophthalmologists in regard to improved diagnosis and treatment of ROP.

Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP): four-years of screening with telemedicine

PURPOSE

To report the four-year experience of the Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP) telemedicine initiative, which was developed to reduce the risk of blindness from retinopathy of prematurity (ROP).

MATERIALS AND METHODS

A retrospective analysis of the SUNDROP archival data between 12/1/2005 and 11/30/2009. A total of 410 consecutively enrolled infants meeting ROP screening criteria had nurse-obtained fundoscopic images evaluated remotely by an ROP specialist. Every infant then received at least one dilated bedside binocular indirect ophthalmoscope (BIO) examination within one week of discharge. All infants were then followed with both telemedicine images and bedside evaluation in clinic according to recommended screening timelines. Primary outcomes were treatment-warranted ROP (TW-ROP), defined as Early Treatment of ROP Type 1, and adverse anatomical outcomes.

RESULTS

The SUNDROP telemedicine screening initiative has not missed any TW-ROP in its four-year evaluation period. A total of 410 infants (820 eyes) were imaged, resulting in 1486 examinations and 18,097 unique images. An average of 12.2 images were obtained per patient. Fourteen infants met TW-ROP criteria on telemedicine examination. After bedside evaluation, 13 infants required laser photocoagulation and one was followed until he spontaneously regressed. Infants with TW-ROP had a significantly lower gestational age (24.9 weeks), birth weight (658.7 grams), and were more likely to be male than the no TW-ROP cohort (all p values <0.00001). Telemedicine had a calculated sensitivity of 100%, specificity of 99.8%, positive predicative value of 92.9% and negative predictive value of 100% for the detection of TW-ROP. No patient progressed to retinal detachment or any adverse anatomical outcome.

CONCLUSIONS

The SUNDROP initiative demonstrated a high degree of diagnostic reliability and was able to capture all infants with TW-ROP. Telemedicine offers a cost-effective, reliable and accurate screening methodology for identifying infants with TW-ROP without sacrificing quality of care.