Entries by Jamie Dunne

When Corneal Sensation Changes, Protection Can Change With It

Pain is one of the body’s warning systems. At the ocular surface, that warning system is especially sensitive because the cornea contains an exceptionally dense network of sensory nerves. When the surface becomes irritated or injured, those nerves help create the sensations that tell us something is wrong. But sensation is only part of their […]

Blinking Is Part of the Tear System

Blinking is so automatic that it is easy to think of it as separate from tear production. Biologically, the two are deeply connected. Each blink spreads the tear film across the cornea, redistributing fluid over a surface that would otherwise begin drying almost immediately. The movement of the eyelids also helps distribute lipids produced by […]

How the Eye Knows It Needs More Tears

Most people rarely think about tear production until they cry. But the tear system is working continuously, making small adjustments that help keep the ocular surface stable from one moment to the next. Those adjustments begin with sensation. Corneal nerves monitor the environment at the front of the eye. As tears evaporate between blinks, the […]

The Trigeminal Nerve: A Communication Pathway for the Ocular Surface

Tear production begins with a gland, but the decision to produce tears is partly a neurological event. To understand why, it helps to follow the path of a signal. The cornea is densely supplied with sensory nerve endings that continually monitor conditions at the ocular surface. When those nerves detect changes such as evaporation, cooling, […]

From the Ocular Surface to the Brain: The Sensory System Behind the Eye

The ocular surface is exposed to the outside world every moment the eyes are open. Wind, temperature, evaporation, airborne particles, light, and the mechanical movement of the eyelids all create potential sources of stress. Yet most of the time, we are barely aware of any of them. That apparent quiet depends on an extraordinarily sensitive […]

oGVHD Does Not Follow a Simple Post-Transplant Timeline

Patients recovering from an allogeneic hematopoietic stem cell transplant become accustomed to milestones. Days, weeks, and months after transplantation carry meaning. Laboratory values are tracked. Medications change. Infection risks evolve. Follow-up schedules shift. It would be convenient if ocular GVHD followed an equally predictable timetable. It does not. Chronic oGVHD often emerges after the immediate […]

Why the Best Time to Understand the Eyes May Be Before Transplant

When ocular symptoms appear after an allogeneic hematopoietic stem cell transplant, one of the first questions is often whether something has changed. That question is much easier to answer when clinicians know where the patient started. A pre-transplant ophthalmic evaluation can establish a baseline picture of the ocular surface before the immune and systemic changes […]

The NIH Eye Score: Measuring More Than What the Eye Looks Like

How do you measure the severity of a disease when the clinical examination tells only part of the story? That problem has shaped the way ocular graft-versus-host disease is assessed. In chronic GVHD, the National Institutes of Health developed an organ scoring system that includes the eyes. The ocular score ranges from no symptoms to […]

Tear-Film Stability: Why Making Tears Is Only Part of the Job

When we think about dry eye, it is natural to focus on quantity. Does the eye produce enough tears? That question matters, particularly in oGVHD, where lacrimal gland damage can cause profound aqueous tear deficiency. But the amount of fluid present is only one part of normal tear function. The tear film must also remain […]

What Corneal Staining Reveals About an Eye Under Stress

The cornea is transparent by design. That is essential for vision, but it can make early surface damage difficult to appreciate with the naked eye. Ocular surface staining gives clinicians a way to make some of that damage visible. During an eye examination, a diagnostic dye such as fluorescein can be applied to the ocular […]