Effect of osteopathy in the cranial field on visual function--a pilot study.

CONTEXT: The effects of osteopathy in the cranial field on visual function-particularly on changes in the visual field and on the binocular alignment of the eyes-have been poorly characterized in the literature. The authors examined whether osteopathy in the cranial field resulted in an immediate, measurable change in visual function among a sample of adults with cranial asymmetry. STUDY DESIGN: Randomized controlled double-blinded pilot clinical trial. SUBJECTS: Adult volunteers between ages 18 and 35 years who were free of strabismus or active ocular or systemic disease were recruited. Inclusion criteria were refractive error ranging between six diopters of myopia and five diopters of hyperopia, regular astigmatism of any amount, and cranial somatic dysfunction. INTERVENTION: All subjects were randomly assigned to the treatment or control group. The treatment group received a single intervention of osteopathy in the cranial field to correct cranial dysfunction. The control group received light pressure of a few ounces of force applied to the cranium without osteopathic manipulative treatment. MEASUREMENTS: Preintervention and postintervention optometric examinations consisted of distant visual acuity testing, Donder push-up (ie, accommodative system) testing, local stereoacuity testing, pupillary size measurements, and vergence system (ie, cover test with prism neutralization, near point of convergence) testing. Global stereoacuity testing and retinoscopy were performed only in preintervention to determine whether subjects met inclusion criteria. Analysis of variance (ANOVA) was performed for all ocular measures. RESULTS: Twenty-nine subjects completed the trial-15 in the treatment group and 14 in the control group. A hierarchical ANOVA revealed statistically significant effects within the treatment group and within the control group (P <.05) in distance visual acuity of the right eye (OD) and left eye (OS), local stereoacuity, pupillary size measured under dim illumination OD and OS, and near point of convergence break and recovery. For the treatment group vs the control group, a statistically significant effect was observed in pupillary size measured under bright illumination OS (P <.05). CONCLUSIONS: The present study suggests that osteopathy in the cranial field may result in beneficial effects on visual function in adults with cranial asymmetry. However, this finding requires additional investigation with a larger sample size and longer intervention and follow-up periods. (ClinicalTrials.gov number NCT00510562).

Accommodative response to PRIO Computer Vision Tester versus printed text.

BACKGROUND: Video display terminals (VDTs) have Gaussian display characteristics. Research suggests that patients accommodate differently to Gaussian images. In the present study, we asked if the accommodative response to the PRIO Computer Vision Tester (a Gaussian image) is different than the accommodative response to a Monocular Estimation Method (MEM) printed text target. METHOD: A normally sighted prepresbyopic group of subjects (N = 60) was recruited from the student body of Nova Southeastern University. Low neutral retinoscopy was performed on each subject at a distance of 50 cm. using both the PRIO vision tester and an MEM target. RESULTS: The PRIO vision tester and the printed text provided essentially the same measures of accommodative response. In addition, the luminance of the PRIO dropped by nearly 40% over the course of 1 hour of intermittent use. CONCLUSION: The PRIO vision tester and traditional nearpoint retinoscopy provided essentially the same measures of accommodative response in prepresbyopic subjects. Further studies should be considered to evaluate whether the change in luminance of the PRIO system has any effect on the measurement of accommodative response.

Assessment of intraocular pressure in children by digital tension.

BACKGROUND: Measurement of intraocular pressure by digital tension is a procedure that warrants study to determine if it could reliably yield pressure measurements for young children. METHODS: Sixty-two children (mean age, 3.8 years) served as subjects for the study. The examiner determined each child's digital tension in mmHg, classifying the measurement as soft to touch, medium to touch, or hard to touch. A masked examiner measured the intraocular pressure with a non-contact tonometer. RESULTS: Ninety-eight percent of the digital tension measurements yielded correct classification of the pressure when compared with non-contact tonometry results. The correlation for the digital tension determination of intraocular pressure with non-contact tonometry measurements was significant: 0.38 (p < 0.05) for O.D. and 0.39 (p < 0.05) for O.S. CONCLUSIONS: This study suggests use of digital tension as a reliable means of obtaining the intraocular pressure of young children. Digital tension tends to under-estimate the intraocular pressure when compared to non-contact tonometry readings.