Poster 77

The Inconsistency Spectrum of Wavefront AnalysisPamela R. Oliver, O.D., M.S., Annette Bade, O.D.,Perla Najman, O.D., Patrick Hardigan, Ph.D., andArmando Barreto, Ph.D., Nova Southeastern University,College of Optometry, 3200 South University Drive, Ft.Lauderdale, Florida 33328

Purpose: Previous studies have shown that measurementsof ocular aberrations are useful in illustrating the image-forming abilities of the human eye even for pathologicalprocesses such as keratoconus. The COAS wavefront ana-lyzer is also utilized for custom LASIK surgery. The pur-pose of this study is to determine consistency of wavefrontanalysis data for patients with near emmetropia, simplemyopia, myopic astigmatism, or keratoconus.Methods: A sample of 53 subjects (age 18 to 39) with a totalof 106 eyes underwent a full ophthalmic examination,including a dilated evaluation, topography and COASwavefront analysis. For each subject the COAS analysis wasrepeated a minimum of 6 times. During the first half of thestudy, all of the patients were dilated for the wavefrontprocedure. Once differences were found comparing theinvestigator refraction and within the analysis measure-ments of individual subjects, the patients were tested bothundilated and dilated.Results: The data were divided into 3 nested-random effectmixed models and illustrated significant differences be-tween eyes using linear contrasts. The Intraclass CorrelationCoefficient (ICC) showed variability within the readings ofeach eye. Coma readings were 1 of the most consistent with0.87. An ICC of 0.80 or lower shows inconsistency, and0.70 shows significant inconsistency. The intraclass corre-lation coefficients for spherical and high order readingswere 0.81 and 0.74, respectively. Many of the other ICCvalues were 0.52 or lower. No improvement in consistencywas revealed between the dilated and undilated analysis.However, ICC for coma readings continued to be one of themost consistent with 0.91. Spherical and high order ICCvalues were 0.69 and 0.78.Conclusion: Unfortunately, there appears to be variability inthe wavefront analysis data derived from the COAS instru-ment in patients with near emmetropia, simple myopia,myopic astigmatism, and keratoconus. The findings suggestthat in order to use the COAS wavefront analyzer clinically,and for future studies, it may be necessary for all aberrationreadings to be evaluated separately.

(Investigators received grant support funding from theNational Science Foundation.)

Poster 78

Retinal Blood Flow is Not Related to IntraocularPressure Reduction Caused by ExerciseJames LaMotte, O.D., Ph.D., Christopher Johnson, O.D.,Brent Hartzell, O.D., and Cecilia Chang, O.D., SouthernCalifornia College Optometry, 2575 Yorba Linda Blvd,Fullerton, California 92831

That intraocular pressure (IOP) decreases after exercise iswell documented, but the mechanism is still being sought.Pulsatile ocular blood flow has been shown to increasefollowing exercise and accompanies the drop in IOP. Pul-satile blood flow as measured by pneumonometry primarilyindicates choroidal flow and not retinal blood flow (RBF).However, laser devices such as the Heidelberg Retina Flow-meter (HRF) are a means to determine RBF in a noninva-sive manner, so we measured the effect on RBF of anexercise workload that causes a reduction in RBF.

Exercise was completed by 30 healthy subjects rangingin age from 22 to 29. They exercised on an ergometerwith a set load for 6 minutes. IOPs were measuredwith Goldmann tonometry before exercise and immediatelyafter the 6-minute session on the ergometer. Retinal bloodflow was also measured before and after exercise with theHRF.

The drop in IOP after exercise was 3.97 mmHg and wassignificant (p � 0.00). There was no significant change (p �0.43) in the RBF after exercise when compared with pre-exercise RBF. Further statistics showed no correlation ofRBF with IOP (p � 0.758).

Previous studies have measured RBF after exercise usingindirect means. The results we found with a direct lasermeasurement of RBF agree with the previous studies andindicate that RBF does not change despite the increasedarterial pressure accompanying exercise. This implies con-striction of retinal vessels and retinal autoregulation duringexercise. If there is a vascular component to the reduction ofIOP from exercise it is more likely choroidal in nature.

Poster 79

Bardet-Biedl Syndrome: A Multidisciplinary ApproachSara Huffman, O.D., M.S., and Karen Fern, O.D., TheUniversity of Houston, College of Optometry, 505 J.Davis Armistead Building, Houston, Texas 77204-2020

Background: Bardet-Biedl syndrome is a condition thataffects 1 in 160,000 people in the general population. It ischaracterized by 5 cardinal signs: retinal pigmentary degen-eration, obesity, mental retardation/learning disabilities,polydactyly, and genital hypoplasia. Though previouslybelieved to be a single-gene recessive disease, current re-search points to a more complex, triallelic inheritance.Retinal dystrophy is the most common feature of Bardet-Biedl syndrome with typical retinitis pigmentosa present inonly 15% to 20% of cases. ERG is always abnormal and canbe used to confirm the diagnosis even when the fundus

302 Optometry, Vol 78, No 6, June 2007

appearance is not characteristic of RP. Other ocular signssuch as myopia and strabismus develop before the retinalchanges and can alert the clinician to the possible diagnosis.Visual acuity is usually reduced by age 6 and continues todecrease such that 65% of patients are legally blind by age20. Management of this condition includes genetic testing/counseling, vision rehabilitation, coordination of vision ser-vices with the school, and comanagement with the PCP forsystemic manifestations.Case Report: A 6-year-old Asian female was referred forevaluation of decreased acuity O.D. and O.S., nystagmus,and strabismus. The patient’s ocular history was negativefor injuries, surgeries, and night blindness. Her medicalhistory was positive for asthma, obesity, and polydactyly.Best-corrected visual acuity with a Bailey-Lovie logMarchart was O.D. 20/276 and O.S. 20/350 with a moderate,compound myopic prescription. Cover test revealed a 25�

constant left exotropia at both distance and near. EOMs andconfrontation visual fields were full in each eye. A high-frequency, small-amplitude jerk nystagmus was noted. Di-lated fundus exam revealed attenuated vessels but wasotherwise normal. The patient displayed classic signs ofBardet-Biedl syndrome and was referred for genetic testingand low vision rehabilitation.Conclusion: Bardet-Biedl syndrome is a rare condition withocular signs found in 93% of patients. As the appearance ofthe retina can be quite variable, clinicians must be attuned toother ocular signs as well as systemic signs to most appro-priately manage these patients. Detailed results of lowvision recommendations along with the latest genetic re-search on this condition will be presented.

Public Health

Poster 80

InfantSEE® Becomes a Toddler: Two Years of ResultsTimothy A. Wingert, O.D., Ralph P. Garzia, O.D., andJeffrey L. Weaver, O.D., M.B.A., M.S., University ofMissouri–St. Louis, College of Optometry, One UniversityBoulevard, Saint Louis, Missouri 63121

Background: The American Optometric Association an-nounced InfantSEE� in June of 2005. InfantSEE is a publichealth program that attempts to identify infants between 6and 12 months of age who are visually at risk, so that anycondition requiring intervention, e.g., amblyopia, may beidentified to maximize treatment effectivity.Method: The records of all infants seen by an InfantSEEparticipant voluntarily submitted to the Clinical Care Groupof the American Optometric Association were collected foranalysis from the launch of the program in June 2005 untilthe end of 2006. All patient-identifying information waseliminated to maintain patient anonymity according toHIPAA privacy standards. The information from each as-

sessment was entered into a database for descriptive statis-tical analysis.Results: Some records were eliminated from considerationbecause they became illegible during submission and thedata could not be extracted reliably. Therefore, the resultsare based on the actual number reporting results for eachparticular survey item. These data extend the results fromthe first 6 months of the program previously reported.Discussion: The InfantSEE program has now become atoddler. In its first 21 months, results were reported on over10,000 infants. The rates at which concerns were expressedare in broad agreement with the literature on the prevalenceof vision problems reported in this population.

As the program becomes more widely known and thenumber of infants seen increases, there exists the opportu-nity to positively impact the number of untreated visionproblems in children. With early and proper treatment,many of these vision problems can be improved. This wouldbe an important step in ensuring the visual welfare ofchildren, improving children’s visual performance and qual-ity of life throughout their lifetimes.

Poster 81

Prevalence of Myopia Among African-American andUgandan SoldiersWilliam H. McAlister, O.D., M.A., M.P.H., andTimothy A. Wingert, O.D., University of Missouri–St.Louis, College of Optometry, One University Boulevard,Saint Louis, Missouri 63121

Background: Controversy exists as to whether refractiveerror is determined by heredity or more influenced byenvironmental causes. This topic has been debated withinoptometry and ophthalmology for years. An often-usedargument by the environmental theorists is the differencethat has been reported in the distribution of refractive errorsbetween those from developed and developing countries.This has led many to hypothesize that environmentalcauses, specifically prolonged and detailed near work, leadto the development of myopia. However, those who areproponents of heredity as the causal factor argue that allinherited traits are not present at birth.Method: As part of the Uganda African Crisis ResponseInitiative, U.S. Army optometric personnel provided visionscreening, examination, and treatment to a battalion sizetask force from the Ugandan Army. All of those screened aspart of this mission were young African men in their earlytwenties. For comparison 3,247 U.S. soldiers were screenedat the 43rd reception battalion at Fort Leonard Wood,Missouri. Of these, 627 were African-American. Thosefrom Uganda who failed had the spherical component oftheir refractive error compared with those U.S. soldiers ofAfrican ancestry who had failed the previous vision screen-ing and were of the same age group. Soldiers from bothgroups were only examined if they failed vision screeningbased on distance visual acuity and/or reported symptoms.

303Poster Presentations