Telemedical evaluation and management of retinopathy of prematurity using a fiberoptic digital fundus camera

Detection of clinically significant retinopathy of prematurity using wide-angle digital retinal photography: a report by the American Academy of Ophthalmology

OBJECTIVE

To evaluate the accuracy of detecting clinically significant retinopathy of prematurity (ROP) using wide-angle digital retinal photography.

METHODS

Literature searches of PubMed and the Cochrane Library databases were conducted last on December 7, 2010, and yielded 414 unique citations. The authors assessed these 414 citations and marked 82 that potentially met the inclusion criteria. These 82 studies were reviewed in full text; 28 studies met inclusion criteria. The authors extracted from these studies information about study design, interventions, outcomes, and study quality. After data abstraction, 18 were excluded for study deficiencies or because they were superseded by a more recent publication. The methodologist reviewed the remaining 10 studies and assigned ratings of evidence quality; 7 studies were rated level I evidence and 3 studies were rated level III evidence.

RESULTS

There is level I evidence from ≥5 studies demonstrating that digital retinal photography has high accuracy for detection of clinically significant ROP. Level III studies have reported high accuracy, without any detectable complications, from real-world operational programs intended to detect clinically significant ROP through remote site interpretation of wide-angle retinal photographs.

CONCLUSIONS

Wide-angle digital retinal photography has the potential to complement standard ROP care. It may provide advantages through objective documentation of clinical examination findings, improved recognition of disease progression by comparing previous photographs, and the creation of image libraries for education and research.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Computer-based image analysis for plus disease diagnosis in retinopathy of prematurity

Presence of plus disease in retinopathy of prematurity (ROP) is an important criterion for identifying ROP requiring treatment. Plus disease is defined by a standard published photograph selected more than 20 years ago by expert consensus. However, diagnosis of plus disease has been shown to be subjective and qualitative. Computer-based image analysis using quantitative methods has potential to improve the objectivity of plus disease diagnosis. The objective was to review the published literature involving computer-based image analysis for ROP diagnosis. The PubMed and Cochrane library databases were searched for the keywords "retinopathy of prematurity" AND "image analysis" AND/OR "plus disease." Reference lists of retrieved articles were searched to identify additional relevant studies. All relevant English-language studies were reviewed. There are four main computer-based systems-ROPtool (area under the receiver operating characteristic curve [AUROC], plus tortuosity 0.95, plus dilation 0.87), RISA (AUROC, arteriolar TI 0.71, venular diameter 0.82), Vessel Map (AUROC, arteriolar dilation 0.75, venular dilation 0.96), and CAIAR (AUROC, arteriole tortuosity 0.92, venular dilation 0.91)-attempting to objectively analyze vessel tortuosity and dilation in plus disease in ROP. Some show promise for identification of plus disease using quantitative methods. This has potential to improve the diagnosis of plus disease and may contribute to the management of ROP using both traditional binocular indirect ophthalmoscopy and image-based telemedicine approaches.

Laser treatment for retinopathy of prematurity

Retinal development involves a complex coordination of events that may be affected by premature delivery, leading to retinopathy of prematurity (ROP), a potential blinding childhood disease. The avascular retina drives further disease progression, with laser ablation reducing unfavorable anatomic outcomes as well as maintaining visual acuity. Trials have stressed the importance of early identification and treatment of threshold and high-risk prethreshold disease to improve outcomes. Retinal ablation with laser photocoagulation should involve entire treatment of avascular retina with a confluent laser spot density, avoiding skip lesions. The current review highlights the use of laser photocoagulation in the treatment of ROP.

Efficacy of wide-field digital retinal imaging for retinopathy of prematurity screening

BACKGROUND

To evaluate the efficacy of wide-field digital retinal imaging for retinopathy of prematurity screening.

DESIGN

Retrospective study in a quaternary public neonatal intensive care unit.

PARTICIPANTS

A total of 108 premature infants screened for retinopathy of prematurity.

METHODS

Retrospective chart and photo review were performed on participants screened by both serial wide-field digital retinal imaging and concurrent binocular indirect ophthalmoscopy. Review of captured digital photos was performed independently by a masked reader. Using the binocular indirect ophthalmoscopy findings as the gold standard, the efficacy of wide-field digital retinal imaging in detecting treatment-requiring retinopathy of prematurity, defined as type 1 prethreshold disease, was determined.

MAIN OUTCOME MEASURES

Sensitivity and specificity of wide-field digital retinal imaging in detecting treatment-requiring retinopathy of prematurity.

RESULTS

Treatment-requiring retinopathy of prematurity was detected in 11 infants by both binocular indirect ophthalmoscopy examination and telemedicine images taken at the same visit. Wide-field digital retinal imaging has a sensitivity of 100% (95% CI: 76.2-100%) and a specificity of 97.9% (95% CI: 93.4-99.7%) in detecting infants with treatment-requiring retinopathy of prematurity. Positive and negative predictive values of wide-field digital retinal imaging were 84.6% (95% CI: 57.8-97.3%) and 100% (95% CI: 96.9-100%), respectively.

CONCLUSIONS

Wide-field digital retinal imaging is accurate, reliable and efficient in detecting treatment-requiring retinopathy of prematurity. Incorporating wide-field digital retinal imaging with telemedicine in standard retinopathy of prematurity management can potentially improve delivery, accessibility, quality and cost of retinopathy of prematurity care.

Stanford University network for diagnosis of retinopathy of prematurity (SUNDROP): 36-month experience with telemedicine screening

BACKGROUND AND OBJECTIVE

to report the 36-month experience of the Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP) telemedicine initiative.

PATIENTS AND METHODS

retrospective analysis of the SUNDROP archival data between December 1, 2005, and November 30, 2008, to evaluate this diagnostic technology for retinopathy of prematurity (ROP) screening. A total of 230 consecutively enrolled infants meeting ROP examination criteria were screened with the Ret-Cam II (Clarity Medical Systems, Pleasanton, CA) and evaluated by the SUNDROP reading center at Stanford University. Outcomes included referral-warranted ROP, treatment-warranted ROP, and anatomic outcomes.

RESULTS

in the initial 36-month period, the SUNDROP telemedicine initiative did not miss any treatment-warranted ROP. A total of 230 infants (460 eyes) were imaged, resulting in 1,059 examinations and 10,921 unique images. Ten infants were identified with referral-warranted ROP: nine underwent laser photocoagulation and one regressed spontaneously. The sensitivity was 100% with a specificity of 99.5%. No patient progressed to retinal detachment or other adverse outcomes.

CONCLUSION

the SUNDROP telemedicine screening initiative for ROP has demonstrated high reliability for identification of treatment-warranted disease. All cases of treatment-warranted disease were captured. There were no adverse outcomes.

The retinopathy of prematurity screening examination: ensuring a safe and efficient examination while minimizing infant discomfort

Retinopathy of prematurity (ROP) examinations in the NICU are necessary to protect vision in premature infants, but the examinations are associated with risk and discomfort. ROP examination risks include adverse effects from mydriatic agents, systemic responses to the stress of examination, and nosocomial infection. Infant discomfort may be lessened by limiting examination length and possibly by measures such as topical anesthetic, oral sucrose, and certain nonpharmacologic techniques. A well-organized ROP service facilitates appropriate scheduling of examinations and education of the infant's parents. This article addresses causes of risk and infant discomfort, providing a framework for developing a safe and efficient ROP service while minimizing infant discomfort.

Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP): 24-month experience with telemedicine screening

PURPOSE

To report the 24-month experience of the Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP) telemedicine initiative.

METHODS

Retrospective analysis of the SUNDROP archival data gathered between 1 December 2005 and 30 November 2007 to evaluate this diagnostic technology for ROP screening. One hundred and sixty consecutively enrolled infants meeting ROP examination criteria were screened with the RetCam II and evaluated by the SUNDROP reading centre at Stanford University. Nurses obtained five or six images in each eye. All patients also received a dilated examination within 1 week of discharge. Outcomes included treatment-warranted retinopathy of prematurity (TW-ROP) and anatomical outcomes.

RESULTS

In the initial 24-month period, the SUNDROP telemedicine initiative has not missed any TW-ROP. A total of 160 infants (320 eyes) were imaged, resulting in 669 exams and 7556 images. Seven infants were identified with TW-ROP; six underwent laser photocoagulation and one regressed spontaneously. The sensitivity was 100%, with specificity of 99.4%. No patient progressed to retinal detachment or other adverse outcomes.

CONCLUSION

The SUNDROP telemedicine screening initiative for ROP has been proven to have a high degree of sensitivity and specificity for the identification of treatment-warranted disease. All cases of treatment-warranted disease were captured. There were no adverse outcomes.

RetCam II Fluorescein Angiography to Guide Treatment and Diagnosis of Coats Disease

Coats disease is a well-described clinical condition featuring peripheral leakage from telangiectatic vasculature, resulting in exudative retinal detachments and exudative deposits. It often affects pediatric patients, requiring examinations and treatments to be performed under anesthesia. It can be difficult to distinguish from retinoblastoma. The RetCam II is a wide-field fundus imaging system that can also obtain intraoperative fluorescein angiography. The case of a 5-year-old girl diagnosed with Coats disease is presented. She presented with an exudative detachment, a submacular nodule, and peripheral telangiectasis. An examination under anesthesia, including angiography, was performed. The angiograph revealed characteristic aneurysms as well as extensive areas of telangiectasis and ischemia not readily visible on examination. The angiogram allowed more diagnostic certainty and guided a more complete treatment than otherwise possible. We propose that fluorescein angiography with the RetCam II system can be a useful tool when examining and treating pediatric patients with Coats disease.

Telemedicine for retinopathy of prematurity diagnosis: evaluation and challenges

Retinopathy of prematurity (ROP) is a vasoproliferative disorder affecting low birth weight infants. Although timely diagnosis and treatment can significantly reduce the risk of severe complications, ROP remains a leading cause of childhood blindness worldwide. Limitations of current disease management strategies include extensive travel and logistical coordination requirements for ophthalmologists and neonatologists, decreasing availability of adequately trained ophthalmologists at the point of care, variability in how retinal findings are diagnosed and documented, and a growing need for ROP care worldwide. Store-and-forward telemedicine is an emerging technology by which medical data are captured for subsequent interpretation by a remote expert. This has potential to improve accessibility, quality, and cost of ROP management. In this article, we summarize the current evaluation data on applications of telemedicine for ROP, particularly involving the diagnostic accuracy and reliability of remote image interpretation by experts. We also address challenges such as the cost-effectiveness of telemedicine, and highlight potential barriers to implementation of these systems. Understanding these principles is essential to determine future directions in research and development of telemedicine systems for ROP, as well as for other ophthalmic diseases.

Speed of telemedicine vs ophthalmoscopy for retinopathy of prematurity diagnosis

PURPOSE

To compare the speed of retinopathy of prematurity (ROP) diagnosis using standard indirect ophthalmoscopy with that of telemedicine.

DESIGN

Prospective, comparative study.

METHODS

Three study examiners (2 pediatric retinal specialists [R.V.P.C., T.C.L.] and 1 pediatric ophthalmologist [M.F.C.]) conducted ROP diagnosis via standard indirect ophthalmoscopy and telemedicine. Each examiner performed: 1) standard ophthalmoscopy on 72 to 150 consecutive infants at his respective institution and 2) telemedical diagnosis on 125 consecutive deidentified retinal image sets from infants from an at-risk population. Time for ophthalmoscopic diagnosis was measured in 2 ways: 1) time spent by the examiner at the infant's bedside and 2) mean total time commitment per infant. Time for telemedicine diagnosis was recorded by computer time stamps in the web-based system. For each examiner, nonparametric statistical analysis (Mann-Whitney U test) was used to compare the distribution of times for examination by ophthalmoscopy vs telemedicine.

RESULTS

Mean (+/- standard deviation [SD]) times for ophthalmoscopic diagnosis ranged from 4.17 (+/- 1.34) minutes to 6.63 (+/- 2.28) minutes per infant. Mean (+/- SD) times for telemedicine diagnosis ranged from 1.02 (+/- 0.27) minutes to 1.75 (+/- 0.80) minutes per infant. Telemedicine was significantly faster than ophthalmoscopy (P < .0001). The total time commitment by ophthalmologists performing bedside ophthalmoscopy for ROP diagnosis, including travel and communication with families and hospital staff, was 10.08 (+/- 2.53) minutes to 14.42 (+/- 2.64) minutes per infant.

CONCLUSIONS

The ophthalmologist time requirement for telemedical ROP diagnosis is significantly less than that for ophthalmoscopic diagnosis. Additional time requirements associated with bedside ROP diagnosis increased this disparity. Telemedicine has potential to alleviate the time commitment for ophthalmologists who manage ROP.

Digital image analysis of plus disease in retinopathy of prematurity

An accurate assessment of retinopathy of prematurity (ROP) is essential in ensuring correct and timely treatment of this potentially blinding condition. Current modes of assessment are based upon clinical grading by expert examination of retinal changes. However, this may be subjective, unreliable and difficult and there has been significant interest in alternative means of measurement. These have been made possible through technological advancements in image capture and analysis as well as progress in clinical research, highlighting the specific importance of plus disease in ROP. Progress in these two fields has highlighted the potential for digital image analysis of plus disease to be used as an objective, reliable and valid measurement of ROP. The potential for clinical and scientific advancement through this method is argued and demonstrated in this article. Along with the potential benefits, there are significant challenges such as in image capture, segmentation, measurement of vessel width and tortuosity; these are also addressed. After discussing and explaining the challenges involved, the research articles addressing digital image analysis of ROP are critically reviewed. Benefits and limitations of the currently published techniques for digital ROP assessment are discussed with particular reference to the validity and reliability of outcome measures. Finally, the general limitations of current methods of analysis are discussed and more diverse potential areas of development are discussed.

Wide-field digital imaging based telemedicine for screening for acute retinopathy of prematurity (ROP). Six-year results of a multicentre field study

Objective

To report on a 6-year experience with wide-field digital imaging based telemedicine (WFDI telemedicine) to reduce the risk for blindness from retinopathy of prematurity (ROP).

Methods

Wide-angle digital fundus cameras (RetCam 120, Massie Lab, Pleasanton, CA, USA) were installed in five neonatal intensive care units (NICUs) in Germany. All prematures at risk were screened with WFDI, and the local ophthalmologists were asked to continue binocular indirect ophthalmoscopy (BIO) according to the German guidelines. Image data were coded and transferred to the Reading Centre in Regensburg. Image evaluation and additional BIO of infants with suspected treatment-requiring ROP (STR-ROP i.e. threshold ROP zone II, prethreshold ROP zone I (type-1 ROP according to ETROP), and ROP possibly requiring treatment but not reliably classifiable from the images) were performed by paediatric ophthalmologists at the Reading Centre. ROP was classified following ICROP, ETROP, and revised ICROP criteria. Outcome measures were incidence of clinically relevant ROP (CR-ROP, i.e. any ROP up to mid-peripheral zone III, ≤ stage 3+), sensitivity to detect STR-ROP, and positive predictive value to detect treatment-requiring ROP (TR-ROP).

Results

In total, 1,222 prematures at risk were screened (mean BW 1395 g, SD ±507 g; mean GA 30 wks, SD ±3 wks). The overall incidence of CR-ROP was 27.6% (71.8% mild = stage 1 to 3 without plus disease, 15.7% prethreshold = type-1 ROP according to ETROP, 12.5% threshold according to ICROP). Zone I disease was present in 3.3%, zone II disease in 76.5%, and zone III disease in 20.2%. According to ETROP, 95 infants were type-1 or type-2 ROP; 67.4% type-1 ROP, and 32.6% type-2 ROP. Of all 1,222 infants, 3.5% received treatment. Following ETROP (not applied in the study), 5.3% would have been treated. The sensitivity for detecting STR-ROP was 100%, and the positive predictive value for TR-ROP 82.4% (28/34) at the time of the first referral (28 infants, ≤ stage 3+ in zone I or II).

Conclusion

All TR-ROP was detected in time, showing the potential of our telemedical screening program. The overall incidence of CR-ROP was comparable to ROP incidences reported in other West European countries.

Retinopathy of prematurity

Retinopathy of prematurity (ROP) is a rapidly evolving area of pediatric ophthalmology. Over the past decade, a new understanding of the pathophysiology of ROP has emerged. Advances in clinical research have lead to modifications in screening criteria and treatment guidelines for ROP. With this knowledge, new treatment modalities such as anti-angiogenic agents are being investigated. This review will highlight some of the current concepts related to ROP.

Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP): 18-month experience with telemedicine screening

PURPOSE

To report the 18-month experience of the Stanford University Network for Diagnosis of Retinopathy of Prematurity (SUNDROP) telemedicine initiative.

DESIGN

Retrospective analysis of the SUNDROP archival data between 1 December 2005 and 30 May 2007, evaluating this new diagnostic technology for ROP screening.

PARTICIPANTS

All 97 consecutively enrolled infants in the SUNDROP network.

METHODS

All patients were screened using the RetCam II, and evaluated by the SUNDROP reading center at Stanford University. Nurses were trained to obtain five images in each eye. All patients were screened by an ophthalmologist trained in diagnosing ROP within 1 week of discharge from the hospital.

MAIN OUTCOME MEASURES

Outcomes included referral-warranted disease, need for treatment, and anatomic outcomes. Referral-warranted disease was defined as any Early Treatment Retinopathy of Prematurity Disease Type 2 or greater, threshold disease, any plus disease, and any stage 4 or higher disease.

RESULTS

In the initial 18-month period, the SUNDROP telemedicine screening initiative has not missed any referral-warranted disease for ROP. A total of 97 infants (194 eyes) were enrolled, resulting in 443 unique examinations and 4,929 unique images. The mean birth weight of the infants was 1,186.9 grams, with a mean gestational age at birth of 28.9 weeks. Seven infants were identified with referral-warranted disease; six patients underwent laser photocoagulation and completely regressed. The one remaining patient regressed spontaneously, and did not require intervention. Calculated sensitivity and specificity was 100% and 98.9% respectively. No patient progressed to retinal detachment or other adverse outcome. Inadequate exposure, artifact, poor visualization of the periphery, and lack of a complete standardized image set in some patients were identified as areas requiring further assessment.

CONCLUSIONS

The SUNDROP telemedicine screening initiative for ROP has proven to have a high degree of sensitivity and specificity for identification of referral-warranted disease. Training was easily implemented. All cases of referral-warranted disease were captured. There were no adverse outcomes.

Retinopathy of prematurity management using single-image vs multiple-image telemedicine examinations

PURPOSE

To compare performance of single-image vs multiple-image telemedicine examinations for retinopathy of prematurity (ROP) diagnosis.

DESIGN

Prospective comparative study.

METHODS

A total of 248 eyes from 67 consecutive infants underwent wide-angle retinal imaging by a trained neonatal nurse at 31 to 33 weeks and/or 35 to 37 weeks postmenstrual age (PMA) at a single academic institution. Data were uploaded to a web-based telemedicine system and interpreted by three masked retinal specialists. Diagnoses were provided based on single images, and subsequently on multiple images, from both eyes of each infant. Findings were compared to a reference standard of indirect ophthalmoscopy by a pediatric ophthalmologist. Primary outcome measures were recommended follow-up interval, presence of plus disease, presence of type-2 or worse ROP, and presence of visible peripheral ROP.

RESULTS

Among the three graders, mean sensitivity/specificity for detection of infants requiring follow-up in less than one week were 0.85/0.93 by single-image examination and 0.91/0.88 by multiple-image examination at 35 to 37 weeks PMA. Mean sensitivity/specificity for detection of infants with type-2 or worse ROP were 0.82/0.95 by single-image examination and 1.00/0.91 by multiple-image examination at 35 to 37 weeks PMA. Mean sensitivity/specificity for detection of plus disease were 1.00/0.86 by single-image examination and 1.00/0.87 by multiple-image examination at 35 to 37 weeks PMA. There were no statistically-significant intragrader differences between accuracy of single-image and multiple-image telemedicine examinations for detection of plus disease.

CONCLUSIONS

Single-image and multiple-image telemedicine examinations perform comparably for determination of recommended follow-up interval and detection of plus disease. This may have implications for development of screening protocols, particularly in areas with limited access to ophthalmic care.

Telemedicine screening for retinopathy of prematurity in developing countries using digital retinal images: a feasibility project

PURPOSE

To determine the feasibility in a middle-level human development country of onsite training, image collection, Internet transfer, and remote grading of digital retinal images from babies screened for retinopathy of prematurity (ROP).

METHODS

Two experienced nurses in a neonatal nursery in Lima, Peru, were trained to take posterior pole (30 degrees ) digital retinal images. Nurses obtained posterior pole retinal images from babies undergoing routine ROP screening and selected images for uploading via Internet for remote evaluation by five masked ROP experts. Results of gradings were compared with same-day clinical diagnostic examinations by an experienced ophthalmologist. Success rates for image acquisition and transfer for grading by expert readers were calculated.

RESULTS

Serial image sets from 26 of the 28 babies enrolled in this study were obtained; two babies were too unstable for imaging. Fifty-six of 58 (96.6%) imaging sessions were successful in obtaining retinal images. Three hundred thirty of 336 (98.2%) images obtained were successfully uploaded to an interactive database. Remote graders judged 93.6% to 97.3% of image sets suitable for ROP grading. Preliminary results indicate sensitivities for detection of serious ROP from 45.5% to 95.2% among individual readers, with specificities of 61.7% to 96.2% when images were gradable.

CONCLUSIONS

A telemedicine approach for ROP screening using digital retinal images obtained by nonophthalmologists is feasible in rapidly developing countries that lack ROP-trained ophthalmologists. If remote grading of digital images is validated as an effective method for identifying referral-warranted ROP (RW-ROP), images obtained by nonphysicians may provide a means of identifying babies who require a diagnostic examination by an ophthalmologist.

A pilot study using "ROPtool" to quantify plus disease in retinopathy of prematurity

PURPOSE

The accurate diagnosis of plus disease is critical to optimize the timing of laser treatment. Unfortunately, it is highly subjective and error-prone. "ROPtool" is a computer program that automatically traces retinal blood vessels and measures their tortuosity and dilation. Our aims were to pilot ROPtool, determine its reliability and validity, and establish appropriate numerical thresholds for plus and pre-plus disease.

METHODS

Twenty high-quality images of the posterior poles of premature infants were collected. Two of the authors (DKW and SFF) independently judged tortuosity and dilation separately as plus, pre-plus, or normal for each quadrant of each image. Disagreements were adjudicated, and the results were considered to be the standard for comparison to ROPtool. These two authors then separately used ROPtool to analyze the same 20 images.

RESULTS

For determination of tortuosity sufficient for plus disease, ROPtool interuser agreement was 95% (19/20), compared with 90% (18/20) agreement by investigator judgment. Eye-level (2 MDs x 20 eyes) sensitivity of ROPtool in detecting tortuosity sufficient for plus disease averaged 95% (21/22) and specificity averaged 78% (14/18). Quadrant-level (2 MDs x 20 eyes x 4 quadrants) sensitivity averaged 85% (66/78) and specificity averaged 77% (63/82). A numeric threshold for pre-plus disease equal to 70% of the average tortuosity of the standard photograph of plus disease resulted in mean sensitivity of 89% (103/116) and mean specificity of 82% (36/44) in distinguishing quadrant-level tortuosity sufficient for pre-plus disease or worse from normal.

CONCLUSIONS

ROPtool can reduce subjectivity and thereby enhance the evaluation of plus and pre-plus disease.

Current understanding and management of retinopathy of prematurity

PURPOSE OF REVIEW

Retinopathy of prematurity is the leading cause of childhood blindness in industrialized countries and is the fifth leading cause of bilateral childhood blindness worldwide. There have been new insights into understanding the factors involved in the pathogenesis of retinopathy of prematurity and related retinal detachment. This review outlines the current recommendations for initiation, frequency, and duration of screening examinations and describes the infants at the highest risk for developing complications from retinopathy of prematurity. The rationale and timing of treatment are also discussed.

RECENT FINDINGS

Infants who undergo early screening and treatment for retinopathy of prematurity have improved long-term functional and structural outcomes compared with those who receive conventional screening and treatment. Patients undergoing surgical repair of retinopathy of prematurity-related detachments (stage 4A, 4B and 5) can have favorable anatomical and functional outcomes. The increased survival of lower birth weight infants has increased the prevalence of aggressive, posterior retinopathy of prematurity that may be unresponsive to conventional treatment.

SUMMARY

While full understanding of the mechanisms that underlie the formation of retinopathy of prematurity and related detachments is not complete, progress has been made in identifying risk factors, screening of high-risk patients, and optimizing the timing of surgical interventions to improve structural and functional outcomes.

Semiautomated analysis of retinal vessel diameter in retinopathy of prematurity patients with and without plus disease

PURPOSE

To determine the feasibility of using semiautomated analysis of digital fundus images to quantify the differences in retinal vascular diameter between retinopathy of prematurity (ROP) patients with and without plus disease.

DESIGN

Case-control study.

METHODS

Thirty eyes of 15 patients with ROP were included in this study. Fourteen eyes of seven patients had plus disease and 16 eyes of eight patients had no evidence of plus disease. Digital fundus images were captured using an NM200D (Nidek, Inc, Aichi, Japan) camera. Vessel diameters were determined using VesselMap software (Imedos, Jena, Germany). The Student t test analysis was used to compare diameters of vessels with and without plus disease.

RESULTS

We found that the average venous diameter is significantly larger by 15% in the group with plus disease.

CONCLUSIONS

VesselMap analysis of digital images is feasible. This method is able to distinguish between veins with and without plus disease, and may be useful in telemedicine screening strategies.

Étude épidémiologique de la rétinopathie du prématuré : les facteurs de risque au CHU de Tours

BACKGROUND

A prospective analysis of the incidence of retinopathy of prematurity (ROP) by documenting clinical perinatal characteristics of affected infants, in an attempt to describe risk factors for ROP.

MATERIALS AND METHODS

Between March 2002 and April 2004, 161 infants, with a gestational age under 31 weeks and/or a birth weight under 1500 g, were screened according to CRYO-ROP guidelines, using direct ophthalmoscopy with a Layden contact lens. Risk factors for ROP were analyzed with the Student and Fischer tests.

RESULTS

ROP developed in 15% of the cases studied, with one out of five at prethreshold or threshold levels of ROP. Gestational age at birth (p<0.0001), low birth weight (p<0.0001), the length of the infant's stay in the neonatal intensive care unit (p<0.0001), the duration of mechanical ventilation (p<0.0001), the duration of oxygen provided (p<0.0001), blood transfusions (p<0.0001), hyaline membrane disease (p=0.0257), and bronchodysplasia (p=0.0012) were significant risk factors for ROP.

CONCLUSION

Despite progress in neonatal intensive care, ROP persists and can be explained by greater and greater prematurity and earlier screening. Effective screening, done between 4 and 6 weeks of life, taking risk factors into account, can improve prognosis.

Remote image based retinopathy of prematurity diagnosis: a receiver operating characteristic analysis of accuracy

BACKGROUND/AIMS

Telemedicine offers potential to improve the accessibility and quality of diagnosis of retinopathy of prematurity (ROP). The aim of this study was to measure accuracy of remote image based ROP diagnosis by three readers using receiver operating characteristic (ROC) analysis.

METHODS

64 hospitalised infants who met ROP examination criteria underwent two consecutive bedside procedures: dilated examination by an experienced paediatric ophthalmologist and digital retinal imaging with a commercially available wide angle camera. 410 images from 163 eyes were reviewed independently by three trained ophthalmologist readers, who classified each eye into one of four categories: no ROP, mild ROP, type 2 prethreshold ROP, or ROP requiring treatment. Sensitivity and specificity for detection of mild or worse ROP, type 2 prethreshold or worse ROP, and ROP requiring treatment were determined, compared to a reference standard of dilated ophthalmoscopy. ROC curves were generated by calculating values for each reader at three diagnostic cut-off levels: mild or worse ROP (that is, reader was asked whether image sets represented mild or worse ROP), type 2 prethreshold or worse ROP (that is, reader was asked whether image sets represented type 2 prethreshold or worse ROP), and ROP requiring treatment.

RESULTS

Areas under ROC curves ranged from 0.747-0.896 for detection of mild or worse ROP, 0.905-0.946 for detection of type 2 prethreshold or worse ROP, and 0.941-0.968 for detection of ROP requiring treatment.

CONCLUSIONS

Remote interpretation is highly accurate among multiple readers for the detection of ROP requiring treatment, but less so for detection of mild or worse ROP.

Retinopathy of prematurity screening by non-retinologists

OBJECTIVE

To detect the screening efficiency of general ophthalmologists (ophthalmic residents) as well as non-ophthalmologists (pediatric residents and nurses posted in neonatal intensive care unit) in screening (ROP) retinopathy of prematurity on the basis of posterior pole vascular changes.

METHODS

Prospective consecutive review in a tertiary care hospital setting. Five groups (each comprising of one ophthalmic resident, one pediatric resident and a nurse) examined the posterior pole vessels of 200 eyes of ROP with a direct ophthalmoscope and compared with an ROP specialist using indirect ophthalmoscope. SPSS (Statistical Package for the Social Science), version 10.0 was used for the analysis.

RESULTS

Ophthalmic residents findings were: (sensitivity 95.68%, specificity 92.85%, positive predictive value 94.81%, negative predictive value 93.97%; pediatric residents findings were : (sensitivity 92.24%, specificity 88.09%, positive predictive value 91.45%, negative predictive value 89.15%); and nurses, finding were: (sensitivity 88.79%, specificity 85.71%, positive predictive value 89.56%, and negative predictive value 84.70%). The results had no statistically significant difference in diagnostic reliability. Kappa agreement analysis was significant for ophthalmic residents (0.887), pediatric residents (0.805) and nurses (0.744) compared with the ROP specialist. None of the children diagnosed with pre-threshold or threshold ROP was thought to have normal posterior pole vessels by the trainees.

CONCLUSIONS

Given adequate training, general ophthalmologists and non-ophthalmologists (pediatricians and nurse practitioners) are independently reliable in detecting posterior pole changes in ROP babies using direct ophthalmoscope and can be provided with a screening protocol.

RetCam imaging for retinopathy of prematurity screening

PURPOSE

Indirect ophthalmoscopy is the gold standard for retinopathy of prematurity (ROP) screening. Screening for ROP with digital imaging has been proposed as a possible alternative. Our goal was to evaluate the longitudinal clinical outcomes of employing digital imaging to detect high-risk ROP.

METHODS

Serial RetCam imaging and indirect ophthalmoscopy were performed on 43 premature infants. A masked reader evaluated the images and made management recommendations that were compared with indirect ophthalmoscopy results. Successful screening was determined by correctly identifying progression to prethreshold or threshold disease with referral for indirect ophthalmoscopy. Unsuccessful screening was determined by failure to identify prethreshold or threshold disease, inaccurately detecting prethreshold or threshold disease, or inability to evaluate for ROP.

RESULTS

No cases of prethreshold or threshold disease were missed by the reader. The reader overestimated prethreshold or threshold disease in 5% of cases. Initial screening in 21% of cases could not be evaluated for ROP secondary to poor image quality. Digital photography had a sensitivity of 100% and specificity of 97.5% in detecting prethreshold and threshold ROP. Positive-predictive value of digital photography was 67% and negative-predictive value was 100%.

CONCLUSIONS

Screening and management of ROP using RetCam imaging did not fail to detect prethreshold or threshold disease when images could be obtained. Ophthalmologic examinations were needed in 20% of cases that did not reach threshold or prethreshold disease because of poor image quality or overestimation of ROP. RetCam screening may safely reduce the overall number of indirect ophthalmologic examinations required.

Fundus fluorescein angiography in the screening for and management of retinopathy of prematurity

OBJECTIVES

To describe the characteristics of fundus fluorescein angiography in retinopathy of prematurity (ROP) and to explore the possible benefits of fundus fluorescein angiography over conventional indirect ophthalmoscopy in the screening for and management of ROP.

PATIENTS AND METHODS

Beginning in January 2003, 23 consecutive patients were recruited for a nonrandomized, investigational trial. Fifty-one sessions of fundus fluorescein angiography were performed as part of ROP screening.

RESULTS

Fundus fluorescein angiography caused no adverse effect. Clear angiograms were easily obtained. There was delayed arm-to-eye fluorescein transit. Leakage of fluorescein was observed in all stage 2 and stage 3 ROP. The leakage resolved soon after treatment. Arteriovenous tufts were found far posterior to the ROP ridge and were a feature of severe ROP.

CONCLUSIONS

Some vascular pathology observed on angiograms cannot be seen on indirect ophthalmoscopy. There was delayed arm-to-eye transit and fluorescein transit within the eyes. Fundus fluorescein angiography allows more objective assessment of disease stage and zone. Regression of ROP is clearly observed on fundus fluorescein angiography.

Is there a role for high-frequency ultrasonography in clinical staging of retinopathy of prematurity?

PURPOSE

To compare 20-MHz ultrasonography with ophthalmoscopy in the staging of retinopathy of prematurity (ROP).

METHODS

We used a handheld 20-MHz ultrasound system to examine 38 eyes of 19 neonates who had an indirect ophthalmoscopic examination (diagnosis masked) within 48 hours prior to ultrasonography. Determination of ROP by indirect ophthalmoscopy was compared with independent identification of ultrasonic features indicative of ROP stages.

RESULTS

In masked cases, ultrasonography correctly identified 13 of 18 (72.2% sensitivity) eyes with zone 2, stage 2 ROP or worse and 19 of 20 (95.0% specificity) normal eyes (zone 2, stage 1 ROP or better) (chi-square, 18.4; P < .001).

CONCLUSION

In the neonatal nursery, a 20-MHz handheld ultrasound system may be an effective screening tool to initially identify ROP for further ophthalmoscopic evaluation and management.

The ‘ideal’ management of retinopathy of prematurity

AIM

Retinopathy of prematurity continues to be a serious, but largely preventable cause of blindness and its detection and treatment is of increasing importance as survival rates of premature babies increase. This is particularly important in Medium Human Development Countries where the guidelines for detection used in the US or UK may not be appropriate.

METHOD

This report addresses identification of infants at risk for retinopathy of prematurity, detection, and treatment of serious disease, and what to do when treatment fails.

RESULTS AND CONCLUSIONS

Retinopathy of prematurity occurs almost exclusively in small premature babies, but the demographic characteristics of these babies vary depending on where they are born. Detection of serious retinopathy requires carefully timed examinations and the treatment criteria will continue to evolve as new therapies are developed. Timely detection and treatment of serious retinopathy of prematurity minimizes the likelihood of blindness, but it is not always successful.

Clinical outcomes associated with telemedicine/telehealth

This paper is a comprehensive review and synthesis of the literature concerning clinical outcomes associated with various telemedicine applications. It starts out with a brief description of the findings reported by similar literature reviews already published. Subsequently, it proposes a conceptual model for assessing clinical outcomes based on Donabedian's formulation of the Medical Care Process. Accordingly, research findings are reported in terms of the relevant components of the medical care process, namely, diagnosis, clinical management, and clinical outcomes. Specific findings are organized according to the designated clinical and diagnostic application. This is followed by a general report of studies dealing with patient satisfaction.

Pilot study of the systemic effects of three different screening methods used for retinopathy of prematurity

PURPOSE

This pilot study compared the physiological and behavioural changes in premature infants undergoing three different methods of screening for retinopathy of prematurity (ROP).

STUDY DESIGN

Prospective randomized cross-over pilot study.

SUBJECTS AND METHODS

Fifteen premature infants requiring screening for ROP were recruited, and physiological and behavioural responses produced by three different methods of screening were compared. The screening methods employed a RetCam 120 and an indirect ophthalmoscope with and without an eyelid speculum. Physiological indices (change in pulse, mean blood pressure and oxygen saturation) and facial responses to pain (brow bulge, eye squeeze, nasolabial fold, mouth opening and the presence of cry) were recorded at five points: before, during and immediately after screening and 10 and 30 min after examination.

RESULTS

Screening with the RetCam 120 and the indirect ophthalmoscope with a speculum both caused a greater change in pulse and mean blood pressure and an increase in facial responses to pain during and immediately after screening as compared to the indirect ophthalmoscope without the speculum. RetCam 120 screening caused greater desaturation than the other methods.

CONCLUSIONS

Although this was a small sample which limits absolute conclusions, the study showed that screening using a RetCam or a speculum and indirect ophthalmoscope caused more stress to the infant, as indicated by physiological and behavioural changes, than simply screening using an indirect ophthalmoscope without a speculum. These effects should be considered when deciding on the appropriate screening method for examining particularly sick infants.

Cost-effectiveness of digital photographic screening for retinopathy of prematurity in the United Kingdom

OBJECTIVES

To compare the cost-effectiveness of alternative methods of screening for retinopathy of prematurity (ROP) in the United Kingdom, including the existing method of indirect ophthalmoscopy by ophthalmologists and digital photographic screening by nurses.

METHODS

A decision tree model was used to compare five screening modalities for the UK population of preterm babies, using a health service perspective. Data were taken from published sources, observation at a neonatal intensive care unit (NICU), and expert judgment.

RESULTS

We estimated that use of standard digital cameras by nurses in NICUs would cost more than current methods (pound 371 compared with pound 321 per baby screened). However, a specialist nurse visiting units with a portable camera would be cheaper (pound 172 per baby). These estimates rely on nurses capturing and interpreting the images, with suitable training and supervision. Alternatively, nurses could capture the images then transmit them to a central unit for interpretation by ophthalmologists, although we estimate that this would be rather more expensive (pound 390 and pound 201, respectively, for NICU and visiting nurses). Sensitivity analysis was used to examine the robustness of estimates.

CONCLUSIONS

It is likely that there is an opportunity to improve the efficiency of the ROP screening program. We estimate that screening by specialist nurses trained in image capture and interpretation using portable digital cameras is a cost-effective alternative to the current program of direct visualization by ophthalmologists. This option would require the development of a suitable portable machine. Direct comparative research is strongly needed to establish the accuracy of the various screening options.

Incidence of retinopathy of prematurity from 1996 to 2000: analysis of a comprehensive New York state patient database

OBJECTIVE

To determine the current incidence of retinopathy of prematurity (ROP) in New York state.

DESIGN

Population-based cohort study.

PARTICIPANTS

Newborn infants (15 691) with initial hospital length of stay >28 days and date of discharge from January 1, 1996, to December 31, 2000. Subjects were identified from the New York Statewide Planning and Research Cooperative System (SPARCS) database, which contains information about every patient hospitalized in New York during this period.

METHODS

Demographic and clinical information about eligible infants was abstracted by searching the SPARCS database. Patients with a discharge diagnosis of ROP or who underwent laser retinal photocoagulation, scleral buckle, or pars plana vitrectomy were identified by searching for appropriate discharge and procedure codes. Incidence of ROP in the study population was determined and analyzed on the basis of birth weight.

MAIN OUTCOME MEASURES

Incidence of any ROP, laser photocoagulation, scleral buckle, and pars plana vitrectomy in study population.

RESULTS

On the basis of SPARCS coding, the overall incidence of any ROP among all newborn infants in New York state during the study period was 0.2% (2284 of 1 167 427), or 1 in 511. The incidence of any ROP in the study population of newborns with initial hospital length of stay >28 days was 20.3% (2152 of 10 596) among infants with birth weight <1500 g and 27.3% (1839 of 6745) among infants with birth weight <1200 g. Among study patients with any ROP, the proportion who underwent laser photocoagulation during initial hospital stay was 9.5% (218 of 2284), and the proportion who underwent scleral buckle or vitrectomy surgery was 0.5% (12 of 2284). Seventeen study newborns with birth weight > or =2000 g had a discharge diagnosis of ROP, although none of these patients required laser or incisional surgery during hospitalization.

CONCLUSIONS

This study involves the largest known cohort of newborns that has been analyzed for ROP. The incidence of ROP in this study is lower than results from previous multicenter clinical trials. However, the diagnosis of ROP in 17 study newborns with birth weight > or =2000 g deserves further investigation and may have implications for ROP screening protocols.

Telemedicine: pediatric applications

The newly developing field of telemedicine has the potential to benefit pediatric care by increasing access to pediatric specialists and services. This report explores the current uses and limitations of telemedicine in pediatrics.

Use of the RetCam 120 for fundus evaluation in uncooperative children

PURPOSE

To report our experience using the RetCam 120 to evaluate suspected retinal pathology in children who did not cooperate for standard in-office examination.

DESIGN

Interventional case series.

METHODS

We reviewed charts of eight consecutive uncooperative children with suspected fundus abnormalities that were photographed using the RetCam 120 as a routine part of patient care.

RESULTS

Three uncooperative children with suspected pathology required RetCam 120 photos because of inadequate fundus examination. Five had pathology or suspected pathology that required more detailed examination. In all of these children, we were able to reach or rule out a diagnosis.

CONCLUSION

The Retcam 120 digital fundus camera has utility as an in-office diagnostic tool for fundus examination of poorly cooperative children and may be a good alternative to examination under anesthesia or sedation in selected cases.

Semiautomated computer analysis of vessel growth in preterm infants without and with ROP

AIMS

To measure characteristics of the retinal blood vessels close to the optic disc in full term and preterm infants, with and without retinopathy of prematurity (ROP), using digital imaging. To determine whether these measures are indicative of the presence or severity of ROP in the retinal periphery.

METHODS

52 digital fundus images from 42 babies were analysed with a semiautomated analysis program developed at Imperial College London. Analysis was limited to the principal temporal vessels close to the optic disc: recording venular diameter and arteriolar diameter and tortuosity.

RESULTS

Each result was categorised by the gestational age of the infant ("very premature" 24-27 weeks, "moderately premature" 28-31 weeks, and "near term" > or =32 weeks) and by the highest stage of ROP present ("no ROP," "mild ROP" stage 1 or 2, and "severe ROP" stage 3). Arteriolar tortuosity was found to vary significantly (Kruskal-Wallis p=0.002) with ROP severity. Although venular and arteriolar diameters increased monotonically with ROP severity the differences were not significant. Venular diameter, arteriolar diameter, and arterial tortuosity did not vary significantly between gestational age groups.

CONCLUSIONS

This study confirms it is possible to quantify the size and tortuosity of retinal blood vessels in term and preterm babies using digital image analysis software. This method detected significant increases in arteriolar tortuosity with increasing ROP severity.

Outcomes and Methods in Telemedicine Evaluation

One hundred and four articles, published from 1966 to 2000, were reviewed to investigate telemedicine evaluation studies in terms of methods and outcomes. A total of 112 evaluations were reported in these 104 articles. Two types of evaluations were evaluated: clinical and nonclinical. Within the clinical evaluations, three were on clinical effectiveness, 26 on patient satisfaction, 49 on diagnostic accuracy, and nine on cost. In the non-clinical evaluations, 15 articles discussed technical issues relating to digital images, such as bandwidth, resolution, and color, and 10 articles assessed management issues concerning efficiency of care, such as avoiding unnecessary patient transfer, or saving time. Of the 112 evaluations, 72 were descriptive in nature. The main methods used in the remaining 40 articles used quantitative methods. Nineteen articles employed statistical techniques, such as receiver operating characteristics curve (three evaluations) and kappa values (seven evaluations). Only one article utilized a qualitative approach to describe a telemedicine system. Currently, there are a number of good reports on diagnostic accuracy, satisfaction, and technological evaluation. However, clinical effectiveness and cost-effectiveness are important parameters, and they have received limited attention. Since telemedicine evaluations tend to explore various outcomes, it may be appropriate to evaluate from a multidisciplinary perspective, and to utilize various methodologies.

Telemedicine approach to screening for severe retinopathy of prematurity: a pilot study

PURPOSE

To evaluate the use of remote reading of digital retinal photographs in the diagnosis of severe (referral-warranted) retinopathy of prematurity (ROP) during longitudinal screening for ROP.

STUDY DESIGN

Prospective, longitudinal cohort study.

SUBJECTS

Forty-four consecutive premature infants at risk for ROP.

METHODS

All infants were examined longitudinally, over a series of examinations, by indirect ophthalmoscopy (gold standard) and digital photography using the RetCam-120 Digital Retinal Camera (Massie Research Laboratories Inc., Dublin, CA) equipped with an ROP lens. Images were stored and read remotely by a masked reader. Referral-warranted ROP was defined as ROP in zone 1, the presence of plus disease or the presence of any stage 3 ROP. We determined whether and when referral-warranted ROP was diagnosed for each eye, of each infant, on each examination, during the course of each of the infant's screening.

RESULTS

Severe (referral-warranted) ROP was diagnosed in 23 eyes by indirect ophthalmoscopy during their series of examinations. Digital photography had a sensitivity of 100% and a specificity of 96% in detecting referral-warranted ROP. The positive predictive value of digital photography was 92%, and the negative predictive value was 100%. In 87% of eyes, referral-warranted ROP was diagnosed by digital photography before or at the same time as indirect ophthalmoscopy.

CONCLUSIONS

Longitudinal remote reading of digital photographs using the RetCam-120 system has excellent specificity and sensitivity in detecting referral-warranted ROP. This pilot study has shown that remote reading of digital photographs has promise for telemedicine strategies in ROP screening.

[Retinopathy of prematurity screening and follow-up with Retcam120: expertise of a team of neonatologists concerning 145 patients]

OBJECTIVES

The high incidence of retinopathy in very premature infants requires strict evaluation and follow-up in neonatal intensive care. The strict organization required in each center, under the responsibility of ophthalmologists, is sometimes puzzling. Therefore, we tested the hypothesis that the introduction of the Retcam allows the neonatologist under the control of ophthalmologist to diagnose retinopathy of prematurity then preventing sequelae, by comparison of pictures interpretations between neonatologists and ophthalmologists.

METHODS

The Retcam gives a 120 degrees picture of the retina which is captured digitally. Then, the interpretation of the neonatologist can be reviewed by the ophthalmologist. We screened premature babies less than 32 weeks of gestation and less than 1500 g, during 1 year, including learning experience. We compared pictures interpretation by neonatologists and ophthalmologists of Retcam recordings.

RESULTS

One hundred and forty-five patients were included. Eight cases of retinopathy were diagnosed with an exact correlation : 3 grade III in zone 2 form plus disease, 1 stage III zone 2 unilateral, 1 stage II in zone 3, 2 stage II en zone 2, 1 grade I zone 3 on at least 5 h contiguous. We had neither false positive, nor false negative. Five infants were treated without significant sequelae.

CONCLUSIONS

Retcam 120 allows an easy diagnosis and follow-up for the retinopathy of prematurity by the neonatologist. We advocate to spread Retcam to the wards where the screening of retinopathy is difficult for the ophthalmology department. As every case requiring therapy is diagnosed, prevention of severe visual handicap is completed. The cost of this apparatus is equivalent to the cost of the care for a congenital blindness.

Features associated with surgical outcome in patients with stages 4 and 5 retinopathy of prematurity

PURPOSE

To present ocular features associated with surgical outcomes in infants with stages 4 and 5 retinopathy of prematurity (ROP).

METHODS

Twenty-two infants (35 eyes) were referred for vitreoretinal surgery for stages 4 and 5 ROP. The following ocular features recorded before the development of retinal detachment requiring surgical intervention were analyzed: clock hour extent of ridge elevation, vitreous state, plus disease, prominent iris vessels, neovascularization, and the presence of exudates. Surgical procedures included scleral buckle, lensectomy-vitrectomy, and lens-sparing vitrectomy. Univariate and multivariate analyses were used to determine features associated with failure to achieve retinal reattachment as the main outcome variable.

RESULTS

Of the 35 eyes that underwent at least one surgical procedure, nine had successful retinal reattachment after the first surgery, and 18 achieved it at the end of follow-up. After accounting for the correlation between the eyes, features significantly associated with surgical failure after the first surgery were vitreous haze, hemorrhage, or organization; plus disease; and neovascularization. The presence of exudates was significantly associated with a successful outcome. When eyes were analyzed by stage at the first procedure, vitreous organization and plus disease were associated with failed retinal reattachment in stage 4 eyes, whereas at least 6 clock hours of ridge elevation and plus disease were significant in stage 5 eyes. The need to perform a lensectomy-vitrectomy was associated with a poor surgical outcome. Neither stage nor number of procedures performed was associated with the development of phthisis.

CONCLUSIONS

Vitreous haze, neovascularization, and plus disease are associated with a poor surgical outcome in eyes that progress after treatment for threshold ROP requiring surgical intervention for retinal detachment. When eyes were divided by stage of ROP at first surgery, plus disease remained a significant variable associated with failed retinal reattachment. Close observation of eyes after laser treatment for threshold ROP is necessary. If neovascularization and plus disease persist and progression of ROP is noted, additional laser should be considered before surgery for retinal detachment. Additional studies with a larger patient sample will be necessary to further define ocular features associated with surgical outcome for ROP.

Retinopathy of prematurity: clinical aspects

There have been many major advances recently that have improved the identification and management of retinopathy of prematurity (ROP). This chapter describes the clinical features of ROP and then considers briefly the incidence and epidemiology of acute phase disease. This is followed by a discussion of the two ROP epidemics and ROP-induced disability in high, low and middle income countries, and how this has been impacted by treatment. The principles and specifics of screening for ROP are considered, focusing on certain topical issues such as whether one screening guideline suits all populations. Treatment has undergone several advances, so that now laser therapy has overtaken cryotherapy as the preferred mode of treatment, and treatment at an earlier stage is now being considered. Finally, the authors attempt to look into the future and wonder how the criteria for treatment will change, and whether innovations in ocular imaging will impact ROP screening in both high and middle income countries.

Laser therapy for retinopathy of prematurity

Retinopathy of prematurity (ROP) is a potentially blinding condition that afflicts preterm infants in the neonatal period. Although advances in scleral buckling and vitrectomy techniques offer hope for those infants suffering from stage 4 or 5 ROP, prevention of progression to these stages offers the most promise for favorable structural and visual outcomes. Proper screening for threshold ROP and treatment with peripheral retinal ablation are the keys to successfully managing ROP. Technological advances in screening tools and portable diode lasers enable ophthalmologists to provide prompt, effective, and safe treatment for patients with threshold ROP.