2024 Charles F. Prentice Medal award lecture: Moments of inspiration

In this Prentice Medal Award lecture, I shall recount my career in vision science in the context of three types of inspiration-"being inspired," "personal inspiration," and "inspiring others." My research has derived inspiration from a variety of sources, such as contemporary and historical research doyens in the ophthalmic field and beyond, artists, Greek philosophers, and abstract constructs such as principles and adages. A given moment of inspiration can range from being a profound experience to a subtle realization during a quiet moment of reflection. Here I shall recount the primary research domains of vision science that have defined my academic career in the context of the three types of inspiration defined above. These research domains are ophthalmic markers of diabetic neuropathy, ocular response to contact lens wear, contact lens-induced parainflammation, contact lens-associated microbial keratitis, grading scales for contact lens complications, contact lens prescribing surveys, material properties of contact lenses, contact lens compliance, history of contact lenses, ocular thermography, and ophthalmic bibliometrics. The notions of "being inspired" and "personal inspiration" are necessarily subjective, although I have endeavored to present them here in a scientific context. Conversely, the notion of "inspiring others" can be objectively gauged, at least in part, by counting article citations or the number of times articles are read online or downloaded from a journal website. In conclusion, my research in the vision sciences has been inspired by others, derived from personal ideas, and perhaps in turn has inspired others.

Non-compliance with lens care and maintenance in diabetic contact lens wearers

We hypothesize that diabetic contact lens wearers may represent a special group displaying higher levels of compliance with their lens care regimens as a result of learned behaviour relating to maintenance of their diabetic condition. To test this hypothesis, a prospective, single centre, controlled, masked study was performed whereby 29 diabetic contact lens patients and 29 non-diabetic control subjects were issued with disposable hydrogel contact lenses and a multipurpose lens care regimen. All participants were given identical instruction on lens care and maintenance. Compliance levels were assessed at a 12-month aftercare appointment by demonstration and questionnaire. Twenty-four different aspects of compliance were scored, 12 by observation and 12 by questionnaire report, of which only two showed a significant difference between the diabetic and control groups. Although the combined population of contact lens wearers was generally compliant, there were examples of non-compliance in both groups. Neither the duration of diabetes nor the degree of metabolic control appeared to have a significant effect on compliance. The results suggest that eye care practitioners cannot assume that diabetic patients will be more compliant with contact lens care and maintenance than non-diabetic patients.

Corneal pathophysiology with contact lens wear

Contact lens wear induces a wide spectrum of changes in the appearance and function of the cornea. The most salient effect of lens wear is the hypoxically induced reduction in the rate of metabolic activity of the corneal epithelium and its sequellae. Other important alterations to corneal health associated with contact lens wear may be caused by antigenic and toxic stimuli, mechanical forces, osmotic effects and carbon dioxide retention. Perhaps the most important task facing the contact lens clinician is to distinguish between an acceptable state of physiological modification and an anomalous or pathological state of hypofunction. In this article, we review the assortment of corneal changes primarily on the basis of the causative agents and time scale with reference to the physical and chemical processes leading to the observed signs or symptoms. This procedure allows a strong foundation for understanding the etiology and management principles for the variety of effects that contact lenses may have on the cornea.