Risk Management

Watch for Warning Signs of a Missed Diagnosis

By Anne M. Menke, RN, PhD OMIC Risk Manager

Digest, Spring 2004

ALLEGATION  Failure to diagnose optic glioma, resulting in delay in surgical removal and blindness in right eye.

DISPOSITION  Settled on behalf of defendant ophthalmologist.

Case Summary

A three-year-old was referred to the insured ophthalmologist with a complaint of headaches. The mother reported an out-turning right eye and said the child needed to sit directly in front of the TV to see. The ophthalmologist noted nystagmus, diagnosed hyperopia OU and exotropia, issued a prescription for a full cycloplegic refraction, and instructed the mother to bring the child back in three months or sooner if headaches and/or blurred vision persisted. Four months later, the ophthalmologist noted resolution of the headache, stable exotropia and hyperopia, slow-beating nystagmus, and stable gaze. The patient was to continue wearing the glasses and return in six months. Three months later, the mother brought the child in when he failed his school eye examination and reported trouble with the glasses. VA was felt to be unreliable but measured 20/30 OD, 20/70 OS. A low-grade allergic conjunctivitis was noted and treated. When he returned as requested for a refraction the following month, the child was failing the school eye exam with and without glasses. Refraction was performed with a mild hyper- opic correction; optic pallor was noted on the fundus examination OD. A trial of patching was planned, after which the child was to return for evaluation. When the mother reported problems with the patching exercise a week later, the ophthalmologist referred her to the local children’s hospital. A work-up there revealed HM to LP only, with marked divergent drift and pale optic disc OD. Neuro- imaging studies revealed an optic glioma, which was treated with surgery, radiation, and chemotherapy.

Analysis

In order to prove malpractice, the care rendered must deviate from the standard and be the cause of the patient’s alleged damages. Experts criticized the insured’s failure to refer the child to a specialist for nystagmus, found on the initial exam, and optic pallor, noted seven months later. The validity of the visual acuity measurement was also challenged, given the precipitous change over a one-week period. Defense experts noted, however, that the patient did benefit from the treatment for exotropia and, more importantly, that earlier diagnosis of this slow-growing tumor would not have affected the treatment or the out- come. The insured ophthalmologist agreed with the defense attorney that these shared concerns, coupled with the child’s poor outcome, could lead to a substantial jury verdict. A decision was therefore reached to settle the case.

Risk Management Principles

“Failure to diagnose” claims are common and account for half of OMIC’s top ten indemnity payments. From both a patient safety and liability perspective, it is important to rule out the worst possible diagnosis as part of the diagnostic process. One of the simplest for- mulations of this axiom is the “witty” or “WIT-D” approach.1 Include the worst thing (W) the patient could have in the differential diagnosis; collect the information (I) needed to rule it in or out; tell (T) the patient and other members of the health care team of your differential diagnosis, planned treat- ment, and any symptoms that should be reported to you; and document (D) your care, decision-making process, and instructions. In this case, nystagmus should have prompted a referral (I) to a neuro-ophthalmologist to rule out a CNS process (W); the optic pallor also required further work-up. There are usually many warning signs of a missed diagnosis. These include repeated, ongoing, or worsening complaints (worsening visual acuity); treatment that does not resolve complaints (kept failing school eye exams); and a diagnosis that does not account for the symptoms (neither the nystagmus nor the optic pallor could be attrib- uted to the hyperopia or exotropia). Such warning signs should prompt the physician to start over by reviewing all chart notes, using the WIT-D approach, accounting for all symp- toms, and seeking a consultation or referral.