Michael F. Chiang

Agreement among pediatric ophthalmologists in diagnosing plus and pre-plus disease in retinopathy of prematurity

PURPOSE Plus disease has become the major criterion for laser treatment in infants with retinopathy of prematurity (ROP), but its assessment is subjective. Our purpose was to compare quadrant-level and eye-level assessment of plus disease and pre-plus disease among 3 experienced ROP examiners and to report their rate of agreement. METHODS One hundred eighty-one high-quality RetCam images from premature infants were graded by 3 of the authors. Dilation and tortuosity were judged separately using a scale of normal or sufficiently abnormal to meet criteria for pre-plus or plus disease. RESULTS There was disagreement on the presence of plus disease for 18 images (10%), on tortuosity sufficient for plus disease (plus tortuosity) for 26 images (14%), and on dilation sufficient for plus disease (plus dilation) for 26 images (14%). Of 67 images judged to have pre-plus disease or worse, there was disagreement on the presence of plus disease for 18 images (27%), on plus tortuosity for 25 images (37%), and on plus dilation for 21 images (31%). For distinguishing plus or pre-plus disease from normal, there was disagreement on pre-plus tortuosity for 38 of 181 images (21%) and on pre-plus dilation for 58 of 181 images (32%). CONCLUSIONS Three experienced ROP examiners disagreed frequently on the diagnosis of plus or pre-plus disease when evaluating cropped clinical photographs of infants, many of which had borderline plus disease. Further study is required to determine the implications of these observations on clinical decision making.

Automating Content Extraction of HTML Documents

Abstract Web pages often contain clutter (such as unnecessary images and extraneous links) around the body of an article that distracts a user from actual content. Extraction of “useful and relevant” content from web pages has many applications, including cell phone and PDA browsing, speech rendering for the visually impaired, and text summarization. Most approaches to making content more readable involve changing font size or removing HTML and data components such as images, which takes away from a webpage’s inherent look and feel. Unlike “Content Reformatting,” which aims to reproduce the entire webpage in a more convenient form, our solution directly addresses “Content Extraction.” We have developed a framework that employs an easily extensible set of techniques. It incorporates advantages of previous work on content extraction. Our key insight is to work with DOM trees, a W3C specified interface that allows programs to dynamically access document structure, rather than with raw HTML markup. We have implemented our approach in a publicly available Web proxy to extract content from HTML web pages. This proxy can be used both centrally, administered for groups of users, as well as by individuals for personal browsers. We have also, after receiving feedback from users about the proxy, created a revised version with improved performance and accessibility in mind.

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.

Cost-Utility Analysis of Telemedicine and Ophthalmoscopy for Retinopathy of Prematurity Management

OBJECTIVE To evaluate the cost-effectiveness of telemedicine and standard ophthalmoscopy for retinopathy of prematurity (ROP) management. METHODS Models were developed to represent ROP examination and treatment using telemedicine and standard ophthalmoscopy. Cost-utility analysis was performed using decision analysis, evidence-based outcome data from published literature, and present value modeling. Visual outcome data were converted to patient preference-based time trade-off utility values based on published literature. Costs of disease management were determined based on 2006 Medicare reimbursements. Costs per quality-adjusted life year gained by telemedicine and ophthalmoscopy for ROP management were compared. One-way sensitivity analysis was performed on the following variables: discount rate (0%-7%), incidence of treatment-requiring ROP (1%-20%), sensitivity and specificity of ophthalmoscopic diagnosis (75%-100%), percentage of readable telemedicine images (75%-100%), and sensitivity and specificity of telemedicine diagnosis (75%-100%). RESULTS For infants with birth weight less than 1500 g using a 3% discount rate for costs and outcomes, the costs per quality-adjusted life year gained were

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

3193 with telemedicine and

Telemedicine for Retinopathy of Prematurity Diagnosis: Evaluation and Challenges

5617 with standard ophthalmoscopy. Sensitivity analysis resulted in ranges of costs per quality-adjusted life year from

Adoption and Perceptions of Electronic Health Record Systems by Ophthalmologists: An American Academy of Ophthalmology Survey

1235 to

Accuracy of retinopathy of prematurity diagnosis by retinal fellows.

18,898 for telemedicine and from

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

2171 to

Interexpert agreement in the identification of macular location in infants at risk for retinopathy of prematurity

27,215 for ophthalmoscopy. CONCLUSIONS Telemedicine is more cost-effective than standard ophthalmoscopy for ROP management. Both strategies are highly cost-effective compared with other health care interventions.