You can’t diagnose or treat a problem if you can’t identify it. Here’s a quick guide on how to navigate the slit-lamp biomicroscope ahead of time to avoid fumbling in front of an anxious patient.

Basic Approach

First, take a quick second to observe the patient as a whole. Once under the microscope, macropathology such as iris heterochromia, periorbital neoplasms and heterotropias can be surprisingly easy (and embarrassing) to miss. Begin with a lower magnification — and fight the urge to jump to obvious lesions. Then figure out your exam algorithm, beginning with external features and working towards deeper structures. Stick to that order so you don’t neglect other important, but more subtle, findings.

Lighting Techniques

Remember that there is a human on the other end of the scope. Cranking up the light intensity may improve your view, but it’s uncomfortable for the patient. If you must do so, give a courtesy heads-up and keep it short. The rule of thumb is to decrease the beam width and/or height as you increase brightness.

Here are a few of the more common and useful lighting techniques that you’ll need to employ:

Diffuse illumination

10x magnification

With this technique, an open beam is directed on the eye at 45°. This is useful for conducting an overall survey of the eye, lids, lashes, caruncle, sclera, surface vessels and media opacities.