Biomedical subjects

H P Orton

Publications and source records attributed to H P Orton.

3 recordsLinked to original sources

PubMed1995

Sensory adaptations in Duane's retraction syndrome.

Knowledge of the sensory status of patients with Duane's retraction syndrome is limited. Fourteen patients with type A Duane's retraction syndrome, aged 6 to 22 years, were assessed prospectively and their sensory findings and the nature of their sensory symptoms detailed. All 14 patients had corrected monocular Snellen acuities of 6/9 or better. Six patients were asymptomatic and 5 of these had dense suppression on lateral versions, were free of diplopia and had variable stereopsis. The 5 bilateral cases were among the asymptomatic group. The remaining 8 patients had weak or absent suppression on lateral versions, variable horizontal diplopia and relatively normal stereopsis. Six were aware of diplopia but were never bothered by it and two spontaneously complained of symptoms related to abnormal binocularity (diplopia in one and asthenopia at near in both). It was not [corrected] possible to differentiate the 2 symptomatic cases from the former 6 on the basis of their sensory findings. Patients with type A Duane's retraction syndrome spontaneously complained of symptoms related to abnormal binocularity. The patients least likely to suffer sensory symptoms were bilateral cases or patients with dense suppression on lateral versions, irrespective of their stereoacuity levels.

Adaptation, Ocular↗

PubMed1992

Whiplash and its effect on the visual system.

Whiplash or indirect injuries to the neck as a consequence of motor vehicle collisions are a common occurrence in which the frequency of ocular complications is largely unknown. Ophthalmic and oculomotor function was investigated in a longitudinal study of 39 cases who had their initial ophthalmological assessment within one week of the whiplash injury. Ten of 39 cases had ocular symptoms and signs which developed shortly after the accident. The principal abnormality in 6 of these was decreased convergence and accommodation, superior oblique muscle paresis in 2, decreased stereoacuity in 1 and bilateral vitreous detachments in 1 patient. All but 2 had complete resolution of their symptoms within 9 months. Four other patients were asymptomatic but had ophthalmic signs which resolved within 3 months. Oculomotor abnormalities following whiplash injuries are generally mild, have a good prognosis, and would appear from this study to be commoner than hitherto expected.

Accidents, Traffic↗

PubMed1987

Counteracting the effects of mydriatics. Does it benefit the patient?

The effect of 2% pilocarpine nitrate in countering mydriasis, cycloplegia, and change in visual acuity due to 0.5% tropicamide was studied in 23 healthy volunteers. There was no significant difference in the decrease in pupil size or the rate of return of accommodation between the eye that received pilocarpine and the control eye. The effect of tropicamide on visual acuity was slight. In four (17%) of 23 eyes that received pilocarpine, visual acuity was reduced to 6/36 or worse. It is suggested that the use of 2% pilocarpine in the attempted reversal of 0.5% tropicamide to improve a patient's vision is not helpful and may possibly be harmful.

Accommodation, Ocular↗