Ocular blood flow in preterm neonates.

Retinopathy of prematurity (ROP) is a disorder affecting low birthweight, preterm neonates. In the preterm eye, the retina is not fully developed and neovascularization may occur at the margin between the developed vascular retina and undeveloped avascular retina. Without timely treatment by laser or intravitreal anti-vascular endothelial growth factor (VEGF) therapy, this can lead to tractional retinal detachment and blindness. Visualization of the retina in regular examinations by indirect ophthalmoscopy is hence the current standard of care, but the exams are stressful and interpretation of images is subjective. The upregulation of VEGF in ROP would suggest an increase in ocular blood flow. In this report, we evaluate the potential of ultrafast plane-wave Doppler ultrasound (PWU) to detect increased flow velocities in the orbital vessels supplying the eye in a gentle exam with objective findings. We imaged both eyes of 50 low-birthweight preterm neonates using 18 MHz PWU. Flow velocity in the central retinal artery (CRA) and vein (CRV), and the short posterior ciliary arteries were determined and values at each ROP Stage compared. We found significantly increased velocities in the CRA and CRV in Stage 3 ROP eyes, where intervention would be considered. We compared multivariate models for identifying Stage 3 eyes comprised solely of clinical factors, solely of Doppler parameters, and clinical plus Doppler parameters. The respective models provided areas under their respective ROC curves of 0.760, 0.812, and 0.904. PWU Doppler represents a gentle, objective means for identifying neonates at risk for ROP that could complement ophthalmoscopy.

Ocular Blood Flow in Preterm Neonates: A Preliminary Report.

Purpose: Retinopathy of prematurity (ROP) is a vision-threatening complication occurring in pre-term neonates. The standard of care entails regular monitoring by dilated ophthalmoscopy examinations, which entail stress and potential morbidity. In this pilot study, we used plane-wave ultrasound (PWUS) to image, measure, and assess the association of blood-flow velocities in the retrobulbar vessels with ROP stages ranging from stage 0 (immature vessels without ROP) to stage 3. Methods: Both eyes of 14 preterm neonates at risk for ROP were examined by 18 MHz PWUS. All but two subjects had a follow-up examination. PWUS was acquired for 1.5 seconds at 3000 compound B-scans/sec. Data were postprocessed to form color-flow images and spectrograms depicting flow velocity in the central retinal artery (CRA), central retinal vein (CRV), and the short posterior ciliary arteries (SPCA). Flow parameters derived from spectrograms were compared by ROP stage. Results: ROP stage was found to correlate with flow velocities. Velocities were significantly elevated with respect to non-ROP eyes in all vessels at stage 3 and in the SPCAs at stage 2. Conclusions: PWUS measurement of blood flow may provide a quantitative, clinically important, and easily tolerated means for detecting and assessing the risk of ROP in preterm neonates. We speculate that the observed increase in flow velocity results from elevated vascular endothelial growth factor (VEGF) in ROP eyes. Translational Relevance: PWUS offers a gentle, nonmydriatic method for monitoring neonates at risk for ROP that would complement ophthalmoscopy.

Parental perceptions toward digital imaging and telemedicine for retinopathy of prematurity management.

BACKGROUND: Telemedicine is an emerging technology with potential to improve care for retinopathy of prematurity (ROP). This study evaluates parental perceptions about digital imaging and telemedicine for ROP care. METHODS: During a 1-year period, one parent of each infant who underwent wide-field retinal imaging for ROP was given a questionnaire designed to evaluate parental perceptions using a 5-point Likert-type scale. Five items assessed perceptions toward digital retinal imaging, and ten items assessed attitudes toward telemedicine. Construct validity of the questionnaire was examined using factor analysis. Responses were summarized using descriptive and correlational statistics. RESULTS: Forty-two parents participated. Factor analysis extracted two factors explaining 79% of the total variance in digital retinal imaging items (Cronbach's alpha = 0.843), and three factors explaining 63% of the total variance in telemedicine items (Cronbach's alpha = 0.631). Among digital imaging items, the highest mean (+/-SD) score was for "digital pictures of my child's retinopathy should be included in the permanent medical record" (4.4 +/- 0.6), and the lowest was for "digital cameras and computers are reliable" (3.8 +/- 0.8). Among telemedicine items, the highest mean (+/-SD) score was for "technology will improve the quality of medical care for my child" (4.3 +/- 0.6), and the lowest was for "technology will make it harder for a patient and doctor to establish a good relationship" (2.6 +/- 1.1). CONCLUSIONS: Parents reported positive perceptions about telemedical ROP diagnosis, but expressed some preference for face-to-face care. Telemedicine has potential to alter the nature of the patient-physician relationship.

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.

Telemedical diagnosis of retinopathy of prematurity intraphysician agreement between ophthalmoscopic examination and image-based interpretation.

OBJECTIVE: To evaluate the intraphysician agreement between ophthalmoscopic examination and image-based telemedical interpretation for retinopathy of prematurity (ROP) diagnosis, when performed by the same expert physician grader. DESIGN: Prospective, nonrandomized, comparative study. PARTICIPANTS: Sixty-seven consecutive premature infants who underwent ROP examination at a major university medical center whose parents consented for participation. METHODS: Infants underwent standard dilated ophthalmoscopy by one of two pediatric ophthalmologists, followed by retinal imaging with a commercially available wide-angle fundus camera by a trained neonatal nurse. Study examinations were performed at 31 to 33 weeks postmenstrual age (PMA) and/or 35 to 37 weeks PMA. Images were uploaded to a Web-based telemedicine system developed by the authors. After a 4- to 12-month period, telemedical interpretations were performed in which each physician graded images from infants upon whom he had initially performed ophthalmoscopic examinations. Diagnoses were classified using an ordinal scale: no ROP, mild ROP, type 2 prethreshold ROP, and treatment-requiring ROP. MAIN OUTCOME MEASURES: Absolute intraphysician agreement and kappa statistic between ophthalmoscopic examination and telemedical interpretation were calculated by eye. All intraphysician discrepancies were reviewed, and underlying causes were classified by eye as no ROP identified by ophthalmoscopic examination, no ROP identified by telemedical interpretation, discrepancy about presence of zone 1 ROP, discrepancy about presence of plus disease, or other discrepancy in classification of ROP stage. RESULTS: Absolute intraphysician agreement between ophthalmoscopic examination and telemedical interpretation was 86.3%. The kappa statistic for intraphysician agreement between examinations ranged from 0.657 (substantial agreement) for diagnosis of treatment-requiring ROP to 0.854 (near-perfect agreement) for diagnosis of mild or worse ROP. Among 206 eye examinations (103 infant examinations), there were 28 (13.6%) intraphysician discrepancies in diagnosis, 8 of which resulted from uncertainty about presence of zone 1 disease and 4 from uncertainty about presence of plus disease. CONCLUSIONS: Intraphysician agreement between ophthalmoscopic examination and telemedical interpretation for ROP was very high. Neither examination modality appeared to have a systematic tendency to overdiagnose or underdiagnose ROP. Diagnosis of zone 1 disease and plus disease were major sources of clinically significant discrepancies.

Telemedical retinopathy of prematurity diagnosis: accuracy, reliability, and image quality.

OBJECTIVE: To prospectively measure accuracy, reliability, and image quality of telemedical retinopathy of prematurity (ROP) diagnosis. METHODS: Two-hundred forty-eight 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) using a standard protocol. Data were uploaded to a Web-based telemedicine system and interpreted by 3 expert retinal specialist graders who provided a diagnosis (no ROP, mild ROP, type 2 prethreshold ROP, treatment-requiring ROP) and an evaluation of image quality for each eye. Findings were compared with a reference standard of indirect ophthalmoscopy by an experienced pediatric ophthalmologist. RESULTS: At 35 to 37 weeks' PMA, sensitivity and specificity for diagnosis of mild or worse ROP were 0.908 and 1.000 for grader A, 0.971 and 1.000 for grader B, and 0.908 and 0.977 for grader C. Sensitivity and specificity for diagnosis of type 2 prethreshold or worse ROP were 1.000 and 0.943 for grader A, 1.000 and 0.930 for grader B, and 1.000 and 0.851 for grader C. At 35 to 37 weeks' PMA, weighted kappa for intergrader reliability was 0.791 to 0.889, and kappa for intragrader reliability for detection of type 2 prethreshold or worse ROP was 0.769 to 1.000. Image technical quality was rated as "adequate" or "possibly adequate" for diagnosis in 93.3% to 100% of eyes. CONCLUSION: A telemedicine system using nurse-captured retinal images has the potential to improve existing shortcomings of ROP management, particularly at later PMAs.