Diagnostic error and neuro-ophthalmology

Diagnosis and classification of optic neuritis

There is no consensus regarding the classification of optic neuritis, and precise diagnostic criteria are not available. This reality means that the diagnosis of disorders that have optic neuritis as the first manifestation can be challenging. Accurate diagnosis of optic neuritis at presentation can facilitate the timely treatment of individuals with multiple sclerosis, neuromyelitis optica spectrum disorder, or myelin oligodendrocyte glycoprotein antibody-associated disease. Epidemiological data show that, cumulatively, optic neuritis is most frequently caused by many conditions other than multiple sclerosis. Worldwide, the cause and management of optic neuritis varies with geographical location, treatment availability, and ethnic background. We have developed diagnostic criteria for optic neuritis and a classification of optic neuritis subgroups. Our diagnostic criteria are based on clinical features that permit a diagnosis of possible optic neuritis; further paraclinical tests, utilising brain, orbital, and retinal imaging, together with antibody and other protein biomarker data, can lead to a diagnosis of definite optic neuritis. Paraclinical tests can also be applied retrospectively on stored samples and historical brain or retinal scans, which will be useful for future validation studies. Our criteria have the potential to reduce the risk of misdiagnosis, provide information on optic neuritis disease course that can guide future treatment trial design, and enable physicians to judge the likelihood of a need for long-term pharmacological management, which might differ according to optic neuritis subgroups.

Patient Personality and Illness Perceptions in Relation to Follow-Up Appointment Adherence in Neuro-Ophthalmology

BACKGROUND

Improving patient attendance at medical follow-up visits may have a notable impact on disease and overall health outcomes. Understanding factors contributing to poor attendance is important for identifying at-risk patients and designing interventions to improve clinical outcomes. Our objective was to identify personality and illness perception factors associated with attendance at recommended follow-up visits in a neuro-ophthalmology practice.

METHODS

New or established patients (≥18 years) with scheduled neuro-ophthalmology (study) or glaucoma (comparison) appointments at a tertiary care academic medical center completed the Brief Illness Perception Questionnaire and Ten-Item Personality Inventory. Physician recommendations made during the visit were recorded (medications, referrals, follow-up, testing, and procedures). A chart review was performed 18 months after enrollment to assess attendance at follow-up appointment and adherence with other physician recommendations. Multiple variable logistic regression models studied associations between follow-up appointment attendance and demographic factors, appointment factors, and survey responses.

RESULTS

Among 152 respondents (97% response rate (152 of 157), aged 19-97 years, 58% female, 34% new, 80 neuro-ophthalmology, 72 glaucoma), neuro-ophthalmology subjects were younger, more likely to be White, non-Hispanic, female and new to the practice than subjects with glaucoma. They reported higher emotional impact, identity, and consequences related to their illness (P = 0.001-0.03). Neuro-ophthalmology physician recommendations included more referrals to other services (17.5% vs 1.4%, P = 0.001, chi-square) and more radiology studies (15% vs 0%, P = 0.001, chi-square), but fewer follow-up visits (75% vs 97%, P < 0.0005, chi-square). Among those with recommended follow-up visits, neuro-ophthalmology subjects had lower rates of on-time appointment attendance (55% vs 77%, P = 0.009, chi-square). In a multiple variable model, on-time follow-up attendance was associated with shorter recommended follow-up interval (≤90 days, P < 0.0005), established (vs new) patient status at enrollment visit (P = 0.04), and glaucoma (P = 0.08), but not subject demographics, illness perception, or personality factors.

CONCLUSIONS

Patient demographics, illness perception, and personality traits were not associated with follow-up appointment attendance and therefore unlikely to be useful for identifying patients at risk of being lost to follow-up. New neuro-ophthalmology patients with a follow-up recommended ≥90 days in advance may benefit from targeted interventions to improve follow-up appointment adherence.

Diagnostic Error in Neuro-ophthalmology: Avenues to Improve

Purpose of Review

To highlight potential avenues to reduce preventable diagnostic error of neuro-ophthalmic conditions and avoid patient harm.

Recent Findings

Recent prospective studies and studies of patient harm have advanced our understanding. Additionally, recent studies of fundus photography, telemedicine, and artificial intelligence highlight potential avenues for diagnostic improvement.

Summary

Diagnostic error of neuro-ophthalmic conditions can often be traced to failure to gather an adequate history, perform a complete physical exam, obtain adequate/appropriate neuroimaging, and generate a complete, appropriate differential diagnosis. Improving triage and identification of neuro-ophthalmic conditions by other providers and increasing access to subspecialty neuro-ophthalmology evaluation are essential avenues to reduce diagnostic error. Further research should evaluate the relationship between misdiagnosis and patient harm, and help identify the most impactful potential targets for improvement.

Mismatch in Supply and Demand for Neuro-Ophthalmic Care

BACKGROUND

Previous research suggests the number of neuro-ophthalmologists in the United States may be below a level that provides sufficient access to neuro-ophthalmic care in much of the United States. However, national estimates of the amount of clinical time spent on neuro-ophthalmology are lacking.

METHODS

The North American Neuro-Ophthalmology Society administered a survey on professional time allocation to its active members. Survey response was 95%. The survey characterized the hours each week each respondent allocated to overall work, clinical work, clinical work in ophthalmology/neurology, and clinical work in neuro-ophthalmology specifically. The survey additionally collected information regarding demographics, current wait times to be seen for new patients, and the difference in clinical time spent in neuro-ophthalmology spent between the current day compared with that shortly after completing clinical training. Linear regression was used to identify potential relationships between the above and average wait time.

RESULTS

On average, responding physicians spent 70% of their clinical time on neuro-ophthalmology. In 6 states, there were no reported practicing neuro-ophthalmologists, and in only 8 states was the clinical full-time equivalent to population ratio below the suggested threshold of 1 for every 1.2 million. The median wait time for a new patient was 6 weeks. This wait time was associated with the fraction of clinical time spent in neuro-ophthalmology (0.2 weeks longer wait for a 10 percentage point increase in the fraction of time spent in neuro-ophthalmology; P = 0.02), and suggestively associated with training (training in ophthalmology was associated with 1.0 week shorter wait time; P = 0.06).

CONCLUSION

The survey suggests that neuro-ophthalmologists are unable to see patients in a timely manner and a decreasing number of clinicians are entering the field. Future interventions should be considered to incentivize neuro-ophthalmology training in ophthalmology and neurology residents such that the United States population is able to appropriately access neuro-ophthalmic care.

Virtual Reality and Augmented Reality- Emerging Screening and Diagnostic Techniques in Ophthalmology: a Systematic Review

In healthcare, virtual reality (VR) and augmented reality (AR) have been applied extensively for many purposes. Similar to other technologies such as telemedicine and artificial intelligence, VR and AR may improve clinical diagnosis and screening services in ophthalmology by alleviating current problems, including workforce shortage, diagnostic error, and underdiagnosis. In the past decade a number of studies and products have used VR and AR concepts to build clinical tests for ophthalmology, but comprehensive reviews on these studies are limited. Therefore, we conducted a systematic review on the use of VR and AR as a diagnostic and screening tool in ophthalmology. We identified 26 studies that implemented a variety of VR and AR tests on different conditions, including VR cover tests for binocular vision disorder, VR perimetry for glaucoma, and AR slit lamp biomicroscopy for retinal diseases. In general, while VR and AR tools can become standardized, automated, and cost-effective tests with good user experience, several weaknesses, including unsatisfactory accuracy, weak validation, and hardware limitations, have prevented these VR and AR tools from having wider clinical application. Also, a comparison between VR and AR is made to explain why studies have predominantly used VR rather than AR.

Importance of the "Rule of the Pupil" in the Modern Neuroimaging Era

ABSTRACT

The "Rule of the Pupil" states that when aneurysms compress the oculomotor nerve, a dilated or sluggishly reactive pupil will result. In previous decades, when cerebral angiography was required to detect an intracranial aneurysm, the "Rule of the Pupil" was used to determine the relative risk of angiography and the likelihood of aneurysmal compression in patients with third nerve palsies (3NPs). Noninvasive imaging including computed tomography angiography (CTA) and magnetic resonance angiography has become readily accessible and can detect all aneurysms large enough to cause 3NPs. It is therefore recommended that all patients with 3NP undergo neuroimaging regardless of pupil status because the consequences of missing an aneurysm are high. The question therefore remains as to whether the "Rule of the Pupil" still has relevance in today's era of modern neuroimaging. We describe a 73-year-old man who developed a left complete, pupil-sparing 3NP and was found to have a paraclinoid meningioma in the left cavernous sinus. As compressive lesions are expected to impair the iris sphincter muscle, no intervention was recommended and his 3NP spontaneously improved within 3 months. We also describe a 54-year-old woman with diabetes and a complete 3NP with a dilated, nonreactive pupil. Initial CTA was reported as normal, but re-review of imaging revealed a posterior communicating artery aneurysm and immediate intervention to coil the aneurysm occurred. The "Rule of the Pupil" is still important in the modern neuroimaging era as demonstrated in cases of incidentally found lesions along the course of the oculomotor nerve and missed radiological findings.

Bilateral calcification of the optic nerve sheath: A diagnostic dilemma

Purpose

To present a case of symptomatic optic nerve sheath calcification and highlight clues and pitfalls for the final diagnosis: bilateral optic nerve sheath meningioma.

Observations

A 48-year-old man presented with painless vision loss in his left eye and findings consistent with left optic nerve atrophy. Magnetic resonance imaging (MRI) displayed thinning of the left optic nerve without contrast-enhancement or evidence of compressive lesions. A supplementary computed tomography angiography (CTA) exposed scattered dural calcification, which included the optic nerves. This was regarded as an incidental finding. The initial diagnosis was ischemic optic neuropathy. Over the next two years, the vision loss in the left eye progressed. A CT of the orbits revealed extensive calcification surrounding both optic nerves. A second MRI was unchanged in comparison to the first MRI. The diagnosis was changed to idiopathic duro-optic calcification. The vision in the left eye further declined over another two years. Consecutive optical coherence tomography measurements of the peripapillary retinal nerve fiber layer suggested bilateral progressive thinning. A third MRI displayed progression of tubular contrast-enhancement surrounding the optic nerves. On the basis of this finding, the patient was finally diagnosed with a bilateral optic nerve sheath meningioma and received external beam radiotherapy.

Conclusion and importance

It is crucial to differentiate an optic nerve sheath meningioma from idiopathic calcification of the optic nerve. In the present case the initial MRI did not detect optic nerve sheath abnormalities. To better demonstrate characteristic calcification, additional CT imaging should be considered when a bilateral optic nerve sheath meningioma is suspected.

Deep Learning for Retinal Image Quality Assessment of Optic Nerve Head Disorders

ABSTRACT

Deep learning (DL)-based retinal image quality assessment (RIQA) algorithms have been gaining popularity, as a solution to reduce the frequency of diagnostically unusable images. Most existing RIQA tools target retinal conditions, with a dearth of studies looking into RIQA models for optic nerve head (ONH) disorders. The recent success of DL systems in detecting ONH abnormalities on color fundus images prompts the development of tailored RIQA algorithms for these specific conditions. In this review, we discuss recent progress in DL-based RIQA models in general and the need for RIQA models tailored for ONH disorders. Finally, we propose suggestions for such models in the future.

Patient Harm Due to Diagnostic Error of Neuro-Ophthalmologic Conditions

PURPOSE

To prospectively examine diagnostic error of neuro-ophthalmic conditions and resultant harm at multiple sites.

DESIGN

Prospective, cross-sectional study.

PARTICIPANTS

A total of 496 consecutive adult new patients seen at 3 university-based neuro-ophthalmology clinics in the United States in 2019 to 2020.

METHODS

Collected data regarding demographics, prior care, referral diagnosis, final diagnosis, diagnostic testing, treatment, patient disposition, and impact of the neuro-ophthalmologic encounter. For misdiagnosed patients, we identified the cause of error using the Diagnosis Error Evaluation and Research (DEER) taxonomy tool and whether the patient experienced harm due to the misdiagnosis.

MAIN OUTCOME MEASURES

The primary outcome was whether patients who were misdiagnosed before neuro-ophthalmology referral experienced harm as a result of the misdiagnosis. Secondary outcomes included appropriateness of referrals, misdiagnosis rate, interventions undergone before referral, and the primary type of diagnostic error.

RESULTS

Referral diagnosis was incorrect in 49% of cases. A total of 26% of misdiagnosed patients experienced harm, which could have been prevented by earlier referral to neuro-ophthalmology in 97%. Patients experienced inappropriate laboratory testing, diagnostic imaging, or treatment before referral in 23%, with higher rates for patients misdiagnosed before referral (34% of patients vs. 13% with a correct referral diagnosis, P < 0.0001). Seventy-six percent of inappropriate referrals were misdiagnosed, compared with 45% of appropriate referrals (P < 0.0001). The most common reasons for referral were optic neuritis or optic neuropathy (21%), papilledema (18%), diplopia or cranial nerve palsies (16%), and unspecified vision loss (11%). The most common sources of diagnostic error were the physical examination (36%), generation of a complete differential diagnosis (24%), history taking (24%), and use or interpretation of diagnostic testing (13%). In 489 of 496 patients (99%), neuro-ophthalmology consultation (NOC) affected patient care. In 2% of cases, neuro-ophthalmology directly saved the patient's life or vision; in an additional 10%, harmful treatment was avoided or appropriate urgent referral was provided; and in an additional 48%, neuro-ophthalmology provided a diagnosis and direction to the patient's care.

CONCLUSIONS

Misdiagnosis of neuro-ophthalmic conditions, mismanagement before referral, and preventable harm are common. Early appropriate referral to neuro-ophthalmology may prevent patient harm.

Diagnostic Error of Neuro-ophthalmologic Conditions: State of the Science

BACKGROUND

Diagnostic error is prevalent and costly, occurring in up to 15% of US medical encounters and affecting up to 5% of the US population. One-third of malpractice payments are related to diagnostic error. A complex and specialized diagnostic process makes neuro-ophthalmologic conditions particularly vulnerable to diagnostic error.

EVIDENCE ACQUISITION

English-language literature on diagnostic errors in neuro-ophthalmology and neurology was identified through electronic search of PubMed and Google Scholar and hand search.

RESULTS

Studies investigating diagnostic error of neuro-ophthalmologic conditions have revealed misdiagnosis rates as high as 60%-70% before evaluation by a neuro-ophthalmology specialist, resulting in unnecessary tests and treatments. Correct performance and interpretation of the physical examination, appropriate ordering and interpretation of neuroimaging tests, and generation of a differential diagnosis were identified as pitfalls in the diagnostic process. Most studies did not directly assess patient harms or financial costs of diagnostic error.

CONCLUSIONS

As an emerging field, diagnostic error in neuro-ophthalmology offers rich opportunities for further research and improvement of quality of care.

Feasibility of a Nonmydriatic Ocular Fundus Camera in an Outpatient Neurology Clinic

OBJECTIVE

To determine the feasibility of nonmydriatic fundus photography in the neurology outpatient setting and to record frequency of clinically relevant fundus findings.

METHODS

Over 5 weeks, fundus photographs were obtained using a nonmydriatic fundus camera in both eyes of adult patients attending our general neurology and headache clinics. A neurologist, who had received 15 minutes of training on the use of the camera, took the photographs. Quality of photographs was graded. Photographs were reviewed by 2 neuro-ophthalmologists. Treating neurologists completed a survey on the use of this technology in the neurology clinic. Feasibility parameters including ease, comfort, speed, quality, and clinical relevance of nonmydriatic fundus photography was assessed.

RESULTS

We obtained 505 fundus photographs of 206 patients. Median time to completion of photographs per patient was 2.12 minutes. Mean rating for ease, comfort, and speed was 9.7 out of 10. Among these, 160 had normal and 44 had abnormal findings. In 114 of 206 patients, neurologists relied on photographs for ocular fundus assessment. In the remaining 92 patients, 18 patients had abnormal photographs, of which neurologists missed the abnormality in 14 (78%). All neurologists preferred nonmydriatic fundus photography over direct ophthalmoscopy.

CONCLUSIONS

Using nonmydriatic fundus photography in an outpatient neurology clinic is feasible without disrupting patient flow or causing patient discomfort. Findings of optic nerve pallor, optic nerve swelling, or normal optic nerves were particularly relevant to these patients seen for headaches or demyelinating disease and helped inform immediate diagnosis and management.

Training in Neurology: Diagnostic Accuracy Among Neurology Residents: The "Close the Loop" Project

OBJECTIVE

To describe cases presented by junior neurology residents and to evaluate resident diagnostic patterns to help address individual and systemic educational needs.

METHODS

For 6 academic years, details of all morning report cases assessed and presented by junior neurology residents were logged, including the resident's independent initial diagnostic impression. Cases were later revisited at subsequent morning reports to "close the loop" on a final diagnosis. We conducted retrospective review to quantify case demographics and to determine resident diagnostic accuracy based on prespecified localization pathways.

RESULTS

Demographic analysis included 1,472 cases; of these, 1,301 qualified for accuracy analysis due to diagnostic uncertainty at time of morning report. Non-neurologic etiologies represented 26.0% of cases. CNS etiologies were the majority (86.0%) of neurologic cases. The most frequent diagnoses were ischemic stroke and seizure. Overall resident diagnostic accuracy was 64.0%. Accuracy was similar between central and peripheral etiologies. Of 1,301 cases, 15.3% were overcalled as neurologic, while neurologic disease was rarely mistaken as non-neurologic (5.1%). Most diagnostic errors (49.1%) occurred when determining whether a case was neurologic. Where in the localization pathway errors occurred varied between etiologies.

CONCLUSION

Overall diagnostic accuracy for neurology junior residents in our cohort was similar to prior work conducted in smaller samples. Analysis of errors, particularly at the critical "neurologic or non-neurologic" decision point, warrants further investigation. Close the loop methodology is simple to employ and can guide educational and quality initiatives to improve neurology resident clinical acumen.

Referral Patterns in Neuro-Ophthalmology

BACKGROUND

Neuro-ophthalmologists specialize in complex, urgent, vision- and life-threatening problems, diagnostic dilemmas, and management of complex work-ups. Access is currently limited by the relatively small number of neuro-ophthalmologists, and consequently, patients may be affected by incorrect or delayed diagnosis. The objective of this study is to analyze referral patterns to neuro-ophthalmologists, characterize rates of misdiagnoses and delayed diagnoses in patients ultimately referred, and delineate outcomes after neuro-ophthalmologic evaluation.

METHODS

Retrospective chart review of 300 new patients seen over 45 randomly chosen days between June 2011 and June 2015 in one tertiary care neuro-ophthalmology clinic. Demographics, distance traveled, time between onset and neuro-ophthalmology consultation (NOC), time between appointment request and NOC, number and types of providers seen before referral, unnecessary tests before referral, referral diagnoses, final diagnoses, and impact of the NOC on outcome were collected.

RESULTS

Patients traveled a median of 36.5 miles (interquartile range [IQR]: 20-85). Median time from symptom onset was 210 days (IQR: 70-1,100). Median time from referral to NOC was 34 days (IQR: 7-86), with peaks at one week (urgent requests) and 13 weeks (routine requests). Median number of previous providers seen was 2 (IQR: 2-4; range:0-10), and 102 patients (34%) had seen multiple providers within the same specialty before referral. Patients were most commonly referred for NOC by ophthalmologists (41% of referrals). Eighty-one percent (242/300) of referrals to neuro-ophthalmology were appropriate referrals. Of the 300 patients referred, 247 (82%) were complex or very complex; 119 (40%) were misdiagnosed; 147 (49%) were at least partially misdiagnosed; and 22 (7%) had unknown diagnoses. Women were more likely to be at least partially misdiagnosed-108 of 188 (57%) vs 39 of 112 (35%) of men (P < 0.001). Mismanagement or delay in care occurred in 85 (28%), unnecessary tests in 56 (19%), unnecessary consultations in 64 (22%), and imaging misinterpretation in 16 (5%). Neuro-ophthalmologists played a major role in directing treatment, such as preserving vision, preventing life-threatening complications, or avoiding harmful treatment in 62 (21%) patients.

CONCLUSIONS

Most referrals to neuro-ophthalmologists are appropriate, but many are delayed. Misdiagnosis before referral is common. Neuro-ophthalmologists often prevent vision- and life-threatening complications.