The use of fluorescein in the examination of corneal integrity was introduced by Pflüger in 1882, just 6 years before the first fitting of contact lenses to humans was reported by Fick. However, it is only in the past 50 years that fluorescein has been used routinely by clinicians for this purpose. Corneal staining is probably the most familiar of all potential contact lens complications since…

Contact lens–induced superior limbic keratoconjunctivitis (CLSLK) is a syndrome comprising a combination of tissue pathologies. Tissues affected include the corneal epithelium and stroma, the limbus and the bulbar and tarsal conjunctivae. Although this condition was first fully described in the literature in the early 1980s, a similar syndrome unrelated to contact lens wear known as Theodore’s superior limbic keratoconjunctivitis (or ‘Theodore's SLK’) had been described about…

The limbus is prone to pathological changes for a variety of reasons. A rich capillary plexus is embedded in the limbus and these vessels may become engorged (see Chapter 15 ) or may constitute the platform from which vessels may penetrate into the cornea (see Chapter 25 ). The limbus is the site of the corneal stem cells, which are the primary source for the differentiation…

‘Limbus’ is the Latin word for ‘border’. When the eye is viewed macroscopically from a social viewing distance of, say, 50 cm, the limbus appears as a reasonably clear circle that forms the outer limit (or ‘border’) of the visible iris. However, defining the exact position of the limbus is more problematic from both a clinical and a histological perspective. When the limbus is viewed under…

Australian ophthalmologist Tom Spring is widely credited as being the first to observe an allergic-like reaction of the upper tarsal conjunctiva, which was later to become known as ‘giant papillary conjunctivitis’. In his 1974 letter to the editor of the Medical Journal of Australia , Spring reported observing the presence of large tarsal papillae, accompanied by discomfort and excessive mucus production in 43% of patients wearing…

Increased conjunctival redness in response to contact lens wear is so easily recognised that it serves as a fundamental indicator to clinicians of the physiological status of the contact lens–wearing eye. It is not surprising that the first two clinical reports of contact lens wearing trials on humans – conducted independently in the late 1880s by Adolf Fick and August Müller – used conjunctival redness as…

Lid-parallel conjunctival folds (LIPCOFs) are sub-clinical folds in the lateral, lower quadrant of the bulbar conjunctiva, parallel to the lower lid margin, which are easily observable with the slit lamp biomicroscope ( Fig. 12.1 ). This phenomenon, first described by Hoh et al. in 1995, has received considerable attention in the literature since then. LIPCOFs are not an adverse ocular reaction; rather, it is a sign…

In the open eye, contact lenses are primarily in physical apposition with the cornea. Well-fitted rigid lenses generally reside almost exclusively on the cornea and only occasionally impinge on the limbus. The situation is different with soft lenses. If the surface area of the cornea is taken to be 132 mm , and the surface area of a soft lens – with typical dimensions of 14.5…

Various forms of organic and inorganic matter can accumulate in the post-lens tear film. These include intrinsic matter, such as desquamated epithelial cells, inflammatory cells and microorganisms, and extrinsic matter, such as dust particles that may have entered the eye from the atmosphere. Most of this matter is flushed away during daily lens wear because of the blink-activated tear pump. The accumulation of such debris during…

Dry eye in contact lens wearers has been identified as a growing public health problem. Between 2015 and 2017, the Tear Film and Ocular Surface Society (TFOS) convened an international collaboration of over 150 experts in the field of dry eye to appraise, synthesise and summarise current knowledge relating to dry eye disease, in a series of meetings known as the Dry Eye Workshop II (DEWS…

Disorders of the eyelashes (cilia) and of the associated structures at the base of the eyelashes such as the eyelash follicles, glands of Zeis and skin of the lid margin, have implications with respect to contact lens wear. Practitioners need to be aware of the possible existence of such conditions in contact lens wearers because it may explain ocular discomfort during lens wear and, in many…

The meibomian glands in the upper and lower eyelids play a critical role in forming and maintaining a viable tear film. Specifically, these glands produce a clear, oily secretion that serves two main functions: (1) forming a hydrophobic lining along the lid margins, thus preventing epiphora, and (2) maintaining a thin lipid layer over the surface of the aqueous tear phase, which retards evaporative fluid loss.…

Contact lens practitioners routinely examine the tarsal conjunctiva and lid margins of their patients, but little attention is generally given to the overall integrity of the eyelids. Eyelid dysfunction, whether caused by contact lens wear or other factors, can pose a problem for contact lens wearers because this could interfere with some of the important roles played by the eyelids. This chapter will concentrate on a…

The concept of the ‘lid wiper’ and a proposed condition brought about by disturbance to this structure, referred to as ‘lid wiper epitheliopathy’ (LWE), were first described by Korb et al. in 2002. The terms ‘lid wiper’ and ‘LWE’ are becoming increasingly common when referring to the aetiology, diagnosis and management of dry eye in contact lens wearers and non–lens wearers. The lid wiper is proposed…

Blinking is a high-speed closure movement of the eyelids of short duration and has both reflex and spontaneous origins. Reflex blinking can be elicited by a variety of external stimuli, such as strong lights, approaching objects, loud noises and corneal, conjunctival or ciliary touch. Contact lenses will cause reflex blinking during lens insertion and removal and other instances of manual manipulation. Furthermore, as a result of…

Although grading performance can be enhanced by interpolation to the nearest 0.1 grade unit, most practitioners find the process of mental interpolation between two discrete grading steps to be quite difficult, notwithstanding the fact that this task becomes easier with practice. One way of partially overcoming this difficulty is to re-engineer the grading scales into a continuous movie sequence, progress through which can be controlled by…

In all health care disciplines, it is important to record as accurately as possible the clinical signs observed in patients. Classically, this has involved a discursive account of the condition being entered on a record card. The severity of the condition would be recorded by using wording that offers a general connotation of the level of severity, such as ‘mild’ or ‘severe’. A potential problem with…

The slit lamp biomicroscope has been the primary instrument for examining the anterior ocular structures since its invention in the early part of the 20th century. In particular, this versatile instrument is invaluable in assessing the effect of contact lens wear on the tear film, cornea, conjunctiva and eyelids. Other simple 20th century optical instruments which were developed to aid contact lens fitting, such as the…