Robert J. Hardy

Results of the Prospective Evaluation of Radial Keratotomy (PERK) Study One Year After Surgery

The Prospective Evaluation of Radial Keratotomy (PERK) study is a nine-center, self-controlled clinical trial of a standardized technique of radial keratotomy in 435 patients who had physiologic myopia with a preoperative refraction between -2.00 and -8.00 diopters. The surgical technique consisted of eight incisions using a diamond micrometer knife with blade length determined by intraoperative ultrasonic pachymetry and the diameter of central clear zone determined by preoperative refraction. At one year after surgery, myopia was reduced in all eyes; 60% were within +/- 1.00 diopter of emmetropia; 30% were undercorrected and 10% were overcorrected by more than 1.00 diopter (range of refraction, -4.25 to +3.38 D). Uncorrected visual acuity was 20/40 or better in 78% of eyes. The operation was most effective in eyes with a refraction between -2.00 and -4.25 diopters. Thirteen percent of patients lost one or two Snellen lines of best corrected visual acuity. However, all but three eyes could be corrected to 20/20. Ten percent of patients increased astigmatism more than 1.00 diopter. Disabling glare was not detected with a clinical glare tester, but three patients reduced their driving at night because of glare. Between six months and one year, the refraction changed by greater than 0.50 diopters in 19% of eyes.

Relief of pain by anterior cervical-spine fusion for spondylosis. A report of sixty-five patients.

An extensive evaluation of the results of anterior spine fusion in sixty-five patients with cervical spondylosis showed that good results with respect to relief of pain were Obtained in 90 per cent. The factors predisposing to more favorable results were: presence of radicular symptoms preoperatively, presence of positive roentgenographic findings at only one vertebral level, presence of myelographic defects which correlated with the levels operated on, and achievement of a solid union without interspace collapse. None of these factors, however, were indispensable to a good result. Those factors which were associated with a bad result were: the presence preoperatively of long tract signs and the preoperative presence of subluxation of a vertebra. Psychological testing (Cornell Index) did not differentiate whether the results would be favorable or unfavorable.

Prevalence of Myopia between 3 Months and 5 '/-- Years in Preterm Infants with and without Retinopathy of Prematurity

Purpose: The purpose of the study was to examine spherical equivalent refractive errors, especially myopia, at six ages between 3 months and 5’/, years post-term in preterm children with birth weights of less than 1251 g. Design: A cohort study. Participants: There were a total of 827 participants in the multicenter study of cryotherapy for retinopathy of prematurity (ROP). Approximately one third of the eyes did not develop ROP, whereas two thirds developed mildto-severe ROP. None of the eyes underwent ctyotherapy. Intervention: Refractive error was measured at 3 months, 1 year, and 5’/2 years after term due date at the five long-term follow-up centers. In most eyes, refractive error also was measured at 2, 3’/*, and 4’/* years. Main Outcome Measure: Myopia was defined as 0.25 diopter (D) or greater with high myopia as 5 D or greater. Results: The proportion of eyes with myopia in this preterm population was increased compared to published data on full-term children and was related to severity of both acute-phase and cicatricial-phase ROP. The percentage of eyes with myopia varied little across ages, ranging from 21.2% at 1 year to 15.7% at 4’1’~ years. The percentage of eyes with high myopia doubled from 1.8% to 3.9% between 3 months and 1 year and remained stable thereafter. The distribution of refractive errors in eyes with mild acute-phase ROP was similar to that of eyes with no ROP. In contrast, eyes with moderate or severe acute-phase ROP showed an increased prevalence of high myopia. The distribution of refractive errors changed between 3 months and 1 year with little change after 1 year. This pattern of refractive development differs from that of full-term infants. Birth weight, severity of ROP, and degree of myopia at 3 months predicted the presence of myopia and high myopia at 5’1, years of age. Conclusions: The distribution of refractive errors in preterm infants from age 3 months to 51/2 years varies with severity of acute-phase ROP and cicatricial disease. Changes in refractive error distribution occur primarily between 3 months and 1 year and involve a decrease in the proportion of eyes with hyperopia and an increase in the proportion with high degrees of myopia. Ophfhalmology 7998; 705:7292- 7300

Severity of Neonatal Retinopathy of Prematurity Is Predictive of Neurodevelopmental Functional Outcome at Age 5.5 Years

Objective. The purpose of this study was to assess the relation between neonatal retinopathy of prematurity (ROP) in very low birth weight infants and neurodevelopmental function at age 5.5 years. Methods. Longitudinal follow-up of children occurred in 2 cohorts of the Multicenter Cryotherapy for Retinopathy of Prematurity Study. The extended natural history cohort followed 1199 survivors of <1251 g birth weight from 5 centers. The threshold randomized cohort (ThRz) followed 255 infants <1251 g from 23 centers who developed threshold ROP and who consented to cryotherapy to not more than 1 eye. At 5.5 years both cohorts had ophthalmic and acuity testing and neurodevelopmental functional status determined with the Functional Independence Measure for Children (WeeFIM). Results. Evaluations were completed on 88.7% of the extended natural history cohort; 87% had globally normal functional skills (WeeFIM: >95). As ROP severity increased, rates of severe disability increased from 3.7% among those with no ROP, to 19.7% of those with threshold ROP. Multiple logistic regression analysis demonstrated that better functional status was associated with favorable visual acuity, favorable 2-year neurological score, absence of threshold ROP, having private health insurance, and black race. Evaluations were completed on 87.4% of the ThRz children. In each functional domain, the 134 children with favorable acuity in their better eye had fewer disabilities than did the 82 children with unfavorable acuity: self-care disability 25.4% versus 76.8%, continency disability 4.5% versus 50.0%, motor disability 5.2% versus 42.7%, and communicative-social cognitive disability 22.4% versus 65.9%, respectively. Conclusion. Severity of neonatal ROP seems to be a marker for functional disability at age 5.5 years among very low birth weight survivors. High rates of functional limitations in multiple domains occur in children who had threshold ROP, particularly if they have unfavorable visual acuity.

The Infant Aphakia Treatment Study: Design and Clinical Measures at Enrollment

OBJECTIVE To compare the use of contact lenses and intraocular lenses (IOLs) for the optical correction of unilateral aphakia during infancy. METHODS In a randomized, multicenter (12 sites) clinical trial, 114 infants with unilateral congenital cataracts were assigned to undergo cataract surgery with or without IOL implantation. Children randomized to IOL treatment had their residual refractive error corrected with spectacles. Children randomized to no IOL treatment had their aphakia treated with a contact lens. MAIN OUTCOME MEASURES Grating acuity at 12 months of age and HOTV visual acuity at 4 1/2 years of age. APPLICATION TO CLINICAL PRACTICE This study should determine whether either treatment for an infant with a visually significant unilateral congenital cataract results in a better visual outcome. RESULTS Enrollment began December 23, 2004, and was completed January 16, 2009. The median age at the time of cataract surgery was 1.8 months. Fifty patients were 4 to 6 weeks of age at the time of enrollment; 32, 7 weeks to 3 months of age; and the remaining 32, more than 3 to less than 7 months of age. Fifty-seven children were randomized to each treatment group. Eyes with cataracts had shorter axial lengths and steeper corneas on average than the fellow eyes. CONCLUSIONS The optimal optical treatment of aphakia in infants is unknown. However, the Infant Aphakia Treatment Study was designed to provide empirical evidence of whether optical treatment with an IOL or a contact lens after unilateral cataract surgery during infancy is associated with a better visual outcome.

Statistical aspects of early termination in the beta-blocker heart attack trial

Abstract The Beta-Blocker Heart Attack Trial was a randomized double blind controlledtrial comparing propranolol with placebo in 3837 patients with a recent myocardial infarction. The trial was terminated on recommendation of the Policy and Data Monitoring Board 9 months before the scheduled closing date. The propranolol group, at the time of the decision, had a 26% lower mortality (z = 2.82). Many issues were considered in this decision. These included the magnitude of the overall results; consistency of results across subgroups, clinical centers, and cause of death; and completeness of follow-up. Two basic statistical methods were used in declaring the overall mortality results significant. The first method evaluated the current survival data taking into account the issue of repeated significance testing. The second method evaluated whether the observed trend was so impressive that the conclusion was unlikely to change even if the trial should continue to the scheduled end. These two methods, as well as other considerations led to the recommendation to discontinue the trial.

Grating visual acuity results in the early treatment for retinopathy of prematurity study

OBJECTIVE To compare grating (resolution) visual acuity at 6 years of age in eyes that received early treatment (ET) for high-risk prethreshold retinopathy of prematurity (ROP) with that in eyes that underwent conventional management (CM). METHODS In a randomized clinical trial, infants with bilateral, high-risk prethreshold ROP (n = 317) had one eye undergo ET and the other eye undergo CM, with treatment only if ROP progressed to threshold severity. For asymmetric cases (n = 84), the high-risk prethreshold eye was randomized to ET or CM. MAIN OUTCOME MEASURE Grating visual acuity measured at 6 years of age by masked testers using Teller acuity cards. RESULTS Monocular grating acuity results were obtained from 317 of 370 surviving children (85.6%). Analysis of grating acuity results for all study participants with high-risk prethreshold ROP showed no statistically significant overall benefit of ET (18.1% vs 22.8% unfavorable outcomes; P = .08). When the 6-year grating acuity results were analyzed according to a clinical algorithm (high-risk types 1 and 2 prethreshold ROP), a benefit was seen in type 1 eyes (16.4% vs 25.2%; P = .004) undergoing ET, but not in type 2 eyes (21.3% vs 15.9%; P = .29). CONCLUSION Early treatment of eyes with type 1 ROP improves grating acuity outcomes, but ET for eyes with type 2 ROP does not. APPLICATION TO CLINICAL MEDICINE: Type 1 eyes should be treated early; however, based on acuity results at 6 years of age, type 2 eyes should be cautiously monitored for progression to type 1 ROP. Trial Registration clinicaltrials.gov Identifier: NCT00027222.

The effect of a reduction in leading causes of death: potential gains in life expectancy.

The potential gains in total expectation of life and in the working life ages among the United States population are examined when the three leading causes of death are totally or partially eliminated. The impressive gains theoretically achieved by total elimination do not hold up under the more realistic assumption of partial elimination or reduction. The number of years gained by a new-born child, with a 30 per cent reduction in major cardiovascular diseases would be 1.98 years, for malignant neoplasms 0.71 years, and for motor vehicle accidents 0.21 years. Application of the same reduction to the working ages, 15 to 70 years, results in a gain of 0.43, 0.26, and 0.14 years, respectively for the three leading causes of death. Even with a scientific break-through in combating these causes of death, it appears that future gains in life expectancies for the working ages will not be spectacular. The implication of the results in relation to the current debate on the national health care policy is noted.

Three-year Results of the Prospective Evaluation of Radial Keratotomy (PERK) Study

The Prospective Evaluation of Radial Keratotomy (PERK) study is a nine-center clinical trial of a standardized technique of radial keratotomy in 435 patients who had simple myopia with a preoperative refractive error between -2.00 and -8.00 diopters (D). We report results for one eye of each patient. The surgical technique consisted of eight incisions using a diamond micrometer knife with the blade length determined by intraoperative ultrasonic pachymetry and the diameter of the central clear zone determined by the preoperative refractive error. At three years after surgery, 58% of eyes had refractive error within one diopter of emmetropia; 26% were undercorrected, and 16% were overcorrected by more than one diopter. Uncorrected visual acuity was 20/40 or better in 76% of eyes. The operation was more effective in eyes with a preoperative refractive error between -2.00 and -4.37 diopters. Between one and three years after surgery, the refractive error changed by 1.00 diopter or more in 12% of eyes, indicating a lack of stability in some eyes.

Does cryotherapy affect refractive error? Results from treated versus control eyes in the cryotherapy for retinopathy of prematurity trial

PURPOSE To evaluate the effect of cryotherapy on refractive error status between ages 3 months and 10 years in children with birth weights of less than 1251 g in whom severe retinopathy of prematurity (ROP) developed in one or both eyes during the neonatal period. DESIGN Randomized clinical trial. PARTICIPANTS Two hundred ninety-one children in whom severe ROP developed during the neonatal period. INTERVENTION Cryotherapy for ROP. MAIN OUTCOME MEASURES Cycloplegic Refraction METHODS The children underwent repeated follow-up eye examinations, including cycloplegic retinoscopy, between 3 months and 10 years after term due date. Refractive error data from all eyes that were randomized to cryotherapy were compared with data from all eyes that were randomized to serve as controls. Refractive error data were also compared for a subset of children who had both a treated and a control eye that could be refracted. RESULTS At all ages, the proportion of treated eyes that were unable to be refracted because of retinal detachment, media opacity, or pupillary miosis was approximately half the proportion of the control eyes that were unable to be refracted. When data from all eyes that could be refracted were considered, the distribution of refractive errors between fewer than 8 diopters (D) of myopia and more than 8 D of hyperopia was similar for treated and control eyes at all ages. The proportion of eyes with 8 D or more of myopia was much higher in treated than in control eyes at all ages after 3 months. In the subset of children who had a treated eye and a control eye that could be refracted, distributions of refractive errors in treated versus control eyes were similar at most ages. CONCLUSIONS In both treated and control eyes, there was an increase in the prevalence of high myopia between 3 and 12 months of age. Between 12 months and 10 years of age, there was little change in distribution of refractive error in treated or control eyes. The higher prevalence of myopia of 8 D or more in treated eyes, as compared with control eyes, may be the result of cryotherapys preservation of retinal structure in eyes that, in the absence of cryotherapy, would have progressed to retinal detachment.