Brief
Course Description

Anatomical Considerations

Although this course
is entitled Anatomical Considerations, it might just as easily be called
Potentially Adverse Effects of Contact Lens Wear. In effect, this course
catalogues many of the potentially negative aspects of contact lens
wear. However, with diligence on the part of the fitter and compliance
on the part of the patient, many of these adverse effects can be greatly
minimized. Proper patient selection, well-fit lenses, and adequate follow-up
will usually result in healthy corneas and satisfied patients. However,
lack of concern, laziness, or simple negligence on the part of either
the fitter or the patient can often cause the sort of problems we’re
about to study. Detecting many of these conditions will often require
considerable clinical experience, and treating them should always be
left to the prescribing practitioner.

The course begins
with a review of certain anatomical structures which effect the contact
lens fitter. These include the tear film, eyelids, conjunctiva, cornea,
and limbus. It is followed by a presentation of some of the potentially
adverse effects of contact lens wear which include corneal edema, corneal
striae, conjunctival and episcleral injection, giant papillary conjunctivitis,
and corneal vascularization. Flourescein, in addition to its value in
helping to evaluate the fit of a contact lens, is also used to facilitate
the precise delineation of specific corneal epithelial defects. It acts
either by pooling in the area of the defect or by staining the underlying
exposed basement membrane or Bowman’s layer. Corneal epithelial staining
patterns could possibly be caused by direct trauma or by defective distribution
of the tear film. This section will illustrate staining patterns which
might be caused by a poorly edged or damaged lens, or by improper insertion,
removal and recentering techniques. We will also discuss staining which
might be the result of defective tear distribution such as “three and
nine-o-clock” staining, or limbal peripheral staining. The course concludes
with a discussion of the biomicroscope or slit-lamp and will emphasize
the importance of this instrument in contact lens fitting. The various
illuminations are discussed, illustrated, and the uses of each are described.