Glaucoma Expert Witness

What Glaucoma Is and Why It Litigates Differently

Glaucoma is a group of diseases in which the optic nerve — the cable carrying visual signals to the brain — is progressively damaged, usually in association with elevated intraocular pressure (IOP). Peripheral vision is lost first, slowly, and the brain fills in the gaps, so patients typically notice nothing until late. Lost nerve tissue does not regenerate. Unlike an acute event with a date, chronic glaucoma damage accrues over years, which complicates both causation and apportionment when a lapse in care is alleged.

Common Litigation Themes

• Missed or delayed diagnosis — elevated pressures, suspicious optic nerve appearance, or abnormal tests documented but not pursued.
• Monitoring adequacy — whether IOP checks, automated visual fields (typically Humphrey perimetry), and OCT (optical coherence tomography) scans of the retinal nerve fiber layer were performed at reasonable intervals and whether progression on those tests prompted treatment escalation.
• Angle-closure emergencies — acute angle closure causes pain, blurred vision, and very high pressure and can destroy vision within days; claims involve missed diagnoses in urgent care settings and failure to perform gonioscopy (a mirrored-lens exam of the eye's drainage angle) in at-risk patients.
• Steroid-induced glaucoma — corticosteroids by any route can raise IOP in susceptible patients; claims typically allege prolonged steroid prescribing without pressure monitoring.
• Surgical complications — recognized risks of trabeculectomy, tube shunts, and minimally invasive glaucoma surgery, and whether they were managed appropriately.

Records and Testing an Expert Reviews

The glaucoma chart is data-rich: serial IOP measurements, gonioscopy findings, central corneal thickness, optic disc photographs, OCT nerve fiber layer analyses with progression software, and serial visual fields with reliability indices. Reviewing the actual printouts rather than summary impressions matters, because progression is often visible in the trend data before it is acknowledged in the narrative. The primer on understanding visual fields explains how these tests are read.

Causation and Apportionment in a Slow Disease

Because glaucomatous loss accrues gradually, the key causation question is usually: how much of the final deficit developed during the period of allegedly substandard care, and how much preceded it or would have occurred despite proper treatment? Serial fields and OCT often permit a reasoned answer. The same structure serves apportionment in California workers' compensation, where Labor Code sections 4663 and 4664 require permanent disability to be apportioned to its causes, including non-industrial disease — an analysis discussed on the apportionment page. Honest opinions also acknowledge that a minority of patients progress despite excellent pressure control, and that normal-tension glaucoma can advance without the elevated IOP that triggers suspicion.

Limitations of the Evaluation

Visual fields are effort-dependent and vary test to test; a single bad field proves little, which is why progression analysis relies on trends across multiple reliable tests. Where a chart contains few fields or scans, the reconstruction of when damage occurred becomes correspondingly uncertain, and the report should say so. Standard-of-care questions are matter-specific and follow the approach described on the standard of care page.

What Attorneys Should Provide

All ophthalmology and optometry records with the actual visual field printouts, OCT reports, and disc photographs; pharmacy records (for steroid exposure and drop adherence questions); and records predating the alleged lapse to establish baseline damage. For disability valuation, the resulting field loss feeds the analysis described under whole person impairment for vision.

Frequently Asked Questions