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.

Evaluation of a computer-based system for plus disease diagnosis in retinopathy of prematurity.

OBJECTIVE: To measure accuracy and reliability of the computer-based Retinal Image Multiscale Analysis (RISA) system compared with those of recognized retinopathy of prematurity (ROP) experts, for plus disease diagnosis. DESIGN: Evaluation of diagnostic test or technology. PARTICIPANTS: Eleven recognized ROP experts and the RISA image analysis system interpreted a set of 20 wide-angle retinal photographs for presence of plus disease. METHODS: All experts used a secure Web site to review independently 20 images for presence of plus disease. Images were also analyzed by measuring individual computer-based system parameters (integrated curvature [IC], diameter, and tortuosity index) for arterioles and venules and by computing linear combinations and logical combinations of those parameters. Performance was compared with a reference standard, defined as the majority vote of experts. MAIN OUTCOME MEASURES: Diagnostic accuracy was measured by calculating sensitivity, specificity, and receiver operating characteristic area under the curve (AUC) for plus disease diagnosis by each expert, and by each computer-based system parameter, compared with the reference standard. Diagnostic agreement was measured by calculating the mean kappa value of each expert compared with all other experts and the mean kappa value of each computer-based system parameter compared with all experts. RESULTS: Among the 11 experts, sensitivity ranged from 0.167 to 1.000, specificity ranged from 0.714 to 1.000, AUC ranged from 0.798 to 1.000, and mean kappa compared with all other experts ranged from 0.288 to 0.689. Among individual computer system parameters, arteriolar IC had the highest diagnostic accuracy, with sensitivity of 1.000; specificity, 0.846; and AUC, 0.962. Arteriolar IC had the highest diagnostic agreement with experts, with a mean kappa value of 0.578. CONCLUSIONS: A computer-based image analysis system has the potential to perform comparably to recognized ROP experts for plus disease diagnosis.

Inaccuracy of stated versus measured parental heights.

Routine measurement of children's height is essential in monitoring for deviations in normal growth velocity. Target adult height of children is estimated by determining an adjusted midparental height. Such determinations are dependent on the accurate acquisition of parental height. Incorrect assessment of parental height will result in inaccurate expectations for the child's height. To observe the difference between stated and measured parental heights within a United States subspecialty setting, prospective acquisition of parental stated and measured heights during the summer months of 2000 and 2001 was examined. Two hundred and thirty-eight parents, 185 mothers and 53 fathers, were measured. The mean values of the stated heights for mothers and fathers were 163.7 cm +/- 6.3 cm and 177.1 cm +/- 8.6 cm, respectively. The corresponding measured heights were 163.0 cm +/- 5.9 cm and 175.2 cm +/- 6.6 cm, respectively. The mean height difference for mothers was 0.69 cm (p<0.001) while the mean height difference for fathers was 1.90 cm (p<0.001). Parents significantly overestimate their height in a clinical setting. Fathers overestimate to a greater degree than mothers. These findings emphasize the need to obtain height measurement of parents along with that of their children in assessing for linear growth delay.

Effects of repeated Valsalva maneuver straining on cardiac and vasoconstrictive baroreflex responses.

INTRODUCTION: We hypothesized that repeated respiratory straining maneuvers (repeated SM) designed to elevate arterial BPs (arterial baroreceptor loading) would acutely increase baroreflex responses. METHODS: We tested this hypothesis by measuring cardiac baroreflex responses to carotid baroreceptor stimulation (neck pressures), and changes in heart rate and diastolic BP after reductions in BP induced by a 15-s Valsalva maneuver in 10 female and 10 male subjects at 1, 3, 6, and 24 h after performing repeated SM. Baroreflex responses were also measured in each subject at 1, 3, 6, and 24 h at the same time on a separate day without repeated SM (control) in a randomized, counter-balanced cross-over experimental design. RESULTS: There was no statistical difference in carotid-cardiac and peripheral vascular baroreflex responses measured across time following repeated SM compared with the control condition. Integrated cardiac baroreflex response (deltaHR/ deltaSBP) measured during performance of a Valsalva maneuver was increased by approximately 50% to 1.1 +/- 0.2 bpm x mm Hg(-1) at 1 h and 1.0 +/- 0.1 bpm x mm Hg(-1) at 3 h following repeated SM compared with the control condition (0.7 +/- 0.1 bpm x mm Hg(-1) at both 1 and 3 h, respectively). However, integrated cardiac baroreflex response after repeated SM returned to control levels at 6 and 24 h after training. These responses did not differ between men and women. CONCLUSIONS: Our results are consistent with the notion that arterial baroreceptor loading induced by repeated SM increased aortic, but not carotid, cardiac baroreflex responses for as long as 3 h after repeated SM. We conclude that repeated SM increases cardiac baroreflex responsiveness which may provide patients, astronauts, and high-performance aircraft pilots with protection from development of orthostatic hypotension.