Steven A. Kane

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 diagnosis of retinopathy of prematurity: accuracy of expert versus non-expert graders

Background/aims To assess accuracy of telemedical retinopathy of prematurity (ROP) diagnosis by trained non-expert graders compared with expert graders. Methods Eye examinations (n=248) from 67 consecutive infants were captured using wide-angle retinal photography (RetCam-II, Clarity Medical Systems, Pleasanton, California, USA). Non-expert graders attended two 1-h training sessions on image-based ROP diagnosis. Using a web-based telemedicine system, 14 non-expert and three expert graders provided a diagnosis for each eye: no ROP, mild ROP, type 2 pre-threshold ROP or treatment-requiring ROP. All diagnoses were compared with a reference standard of dilated indirect ophthalmoscopy by an experienced paediatric ophthalmologist. Results For detection of type 2 or worse ROP, the mean (range) sensitivities and specificities were 0.95 (0.94–0.97) and 0.93 (0.91–0.96) for experts, 0.87 (0.71–0.97) and 0.73 (0.39–0.95) for resident non-experts, and 0.73 (0.41–0.88) and 0.91 (0.84–0.96) for student non-experts, respectively. For detection of treatment-requiring ROP, the mean (range) sensitivities and specificities were 1.00 (1.00–1.00) and 0.93 (0.88–0.96) for experts, 0.88 (0.50–1.00) and 0.84 (0.71–0.98) for resident non-experts, and 0.82 (0.42–1.00) and 0.92 (0.83–0.97) for student non-experts, respectively. Conclusions Mean sensitivity and specificity of trained non-experts were lower than that of experts, although several non-experts had high accuracy. Development of methods for training non-expert graders may help support telemedical ROP evaluation.

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.

Late-recognized primary congenital glaucoma.

PURPOSE To describe a cohort of children with late-recognized primary congenital glaucoma (LRPCG), including age of presentation, age-related diagnostic signs, clinical abnormalities, and results of glaucoma surgery. METHODS The medical records of 31 patients (49 eyes) with PCG recognized after 1 year of age were reviewed retrospectively. Patients were confirmed to have PCG based on their increased intraocular pressure (IOP), anterior segment abnormalities including findings on gonioscopy, and the absence of other causes of childhood glaucoma. The outcome of glaucoma surgery was reviewed and success measured by assessment of the relative control of IOP, occurrence of significant complications, and need for additional glaucoma surgery. RESULTS Average age at diagnosis of glaucoma was 4.7 years (36% diagnosed at > 4 years of age). The most common initial diagnostic signs were corneal enlargement (46%, average age of 2.0 years), photophobia (20%, average age of 3.3 years), and suspected poor visual acuity (32%, average age of 9.9 years). Corneal cloudiness was not an initial sign for any patient. Haabs striae were present in 60% of the affected 49 eyes. Gonioscopy findings were abnormal in 82%, but the ciliary body band was seen in 81% and the scleral spur was visible in 47%. Sixty-one goniotomy procedures were performed for 39 eyes with overall success in 95% (37 eyes) and complete success in 65% (27 eyes). The final visual acuity was 20/200 or worse in 31% (15 eyes) and 20/40 or better in 60% (29 eyes). CONCLUSIONS An awareness of and familiarity with the subtle diagnostic signs of LRPCG can enable its differentiation from primary juvenile glaucoma and contribute to earlier recognition and treatment. Glaucoma surgery is often required for LRPCG and goniosurgery is the recommended initial procedure.