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Biomedical subjects

R Weale

Publications and source records attributed to R Weale.

10 recordsLinked to original sources
PubMed1995

Why does the human visual system age in the way it does?

The tentative observation that the decrease of lenticular glutathione in man and in cattle may be under genetic control is extended to other biological functions which show a systematic reduction with age. Ocular and visual parameters are shown to decline consistently with the view that the human eye has evolved in keeping with other biological functions sustaining a life-span of approximately 120 years. Analysis of the data suggests that presbyopia represents an outlier in the distribution of ocular attributes, and should not be used as a biomarker for ageing.

Aged↗
PubMed1994

On the invention of the ophthalmoscope.

The author offers an English translation of three passages of Purkinje's Commentatio de examine physiologico organi visus (1823). He shows that Purkinje made three inventions: (1) by using a transparent mirror, (2) by anticipating Maxwellian illumination, and (3) by providing the first recorded ophthalmic examination of animal and human eyes.

Animals↗
PubMed1993

Is the season of birth a risk factor in glaucoma?

Several lines of research suggest that some systemic diseases, often associated with age-related conditions, may present with enhanced prevalences owing to very early influences on human development. This paper describes an analysis of 1264 adult Caucasian patients presenting either with primary open angle or narrow angle/angle closure glaucoma on the one hand, or with age-related cataract on the other. In addition, data on cataracts and primary open angle glaucoma on 254 patients of Caribbean origin and 190 of south east Asian origin were also examined. Patients were classified with respect to sex and season of birth. These variables can play a statistically significant role in the prevalence of glaucoma, which raises the possibility that environmental influences may be involved.

Aged↗
PubMed1992

The Oqual: a new device for measuring the optical quality of the anterior segment of the human eye.

An attachment to (Haag-Streit and Topcon) slit-lamps is described. This permits projection of a patterned target into the eye and the visual or photographic analysis of the details of the image reflected from the posterior surface of the crystalline lens. A numerical assessment can then be made of the optical quality of the crystalline lens as a whole, although scanning it is also possible. The attachment has also been used successfully for the objective assessment of the patient's post-operative visual acuity following kerato-refractive procedures.

Anterior Eye Segment↗
PubMed1980

A note on a possible relation between refraction and a disposition for senile nuclear cataract.

A study was made of records of patients who have had at least 1 senile cataract removed and for whom refraction records were available. The risk of a cataract occurring was determined as a function of precataractous refraction. Emmetropia was found to provide a sharp borderline between the low risk (about 1:1000) of hypermetropes and an increasing risk (about 1:100) for moderate myopes for patients in their early 60s.

Aged↗
PubMedDate not supplied

Presbyopia toward the end of the 20th century.

Recent advances in our understanding of the anatomy and physiology of accommodation have contributed to current concepts of the possible constituent factors in presbyopia, largely supplanting the long-held belief that presbyopia is due to sclerosis of the crystalline lens. In this review, the author examines epidemiologic, basic scientific, and clinical evidence for a multifactorial decrease in accommodative amplitude with age. Methods of measurement, oculomotor effects of presbyopia, and approaches to correcting it are also considered.

Accommodation, Ocular↗