UK Locum Optoms: This Is The Most Overlooked Number On The Slip...

We’ve all been there: You’re halfway through a busy clinic, you glance at the autorefractor printout to check the reflex, and you move straight to the refraction. But if you’re ignoring that small value labeled "PS," you might be walking blindly into a difficult appointment.

That Pupil Size (PS) measurement isn’t just data filler. It is a critical window into your clinical workflow for the next 20 minutes.

Why PS is a Clinical "Heads-Up"

The autorefractor captures the PS measurement in ambient room lighting. This gives you an immediate, objective preview of your patient's baseline pupil diameter before they even sit in your chair.

• The 4mm Threshold: A PS measurement of 4mm or less is your first red flag for a challenging fundoscopy.
• The "Small Pupil" Struggle: As the pupil size drops, your field of view constricts. Attempting to view the peripheral retina, macula, or even a clear view of the optic nerve through a 3mm aperture is like trying to inspect a room through a keyhole.

Proactive Clinical Planning

Paying attention to the PS value allows you to pivot your clinical plan before you struggle.

1. Anticipate Difficulty: If you see a value below 3.5mm, expect to spend significantly more time maneuvering your Volk lens and hunting for pathology.
2. Early Dilation: For patients with diabetes or those requiring a comprehensive peripheral retinal exam, a low PS value is an immediate indicator that you should consider dilation early in the exam.
3. Manage Your Clock: Knowing you need to dilate at the start of the appointment saves you from the "failed fundoscopy" mid-exam that throws your entire afternoon off schedule.

The Bottom Line

Modern optometry is about working smarter, not harder. Use every tool at your disposal—even the small ones. By checking the PS value first, you ensure a higher standard of care and a much smoother day in the testing room.