Common errors in the use of magnetic resonance imaging for neuro-ophthalmic diagnosis

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.

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.

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.

Diagnostic error and neuro-ophthalmology

PURPOSE OF REVIEW

This review summarizes the recent literature on diagnostic error relevant to the practice of neuro-ophthalmology, and evaluates the potential for increased access to neuro-ophthalmology to decrease rates of diagnostic error, thereby reducing medical harm and spending on unnecessary tests and treatments.

RECENT FINDINGS

Despite medical advances, current research continues to show alarmingly high rates of diagnostic error. Research into diagnostic error shows that many of these errors can be traced to cognitive errors. Recent studies on diagnostic problems relevant to neuro-ophthalmology, including studies of misdiagnosis of posterior communicating artery aneurysms, idiopathic intracranial hypertension, optic neuritis, and optic nerve sheath meningiomas, have identified major causes of diagnostic error in these conditions.

SUMMARY

Studies on diagnostic error in neuro-ophthalmologic conditions show that prior to evaluation by a neuro-ophthalmologist, patients may undergo unnecessary tests and treatments that are costly and potentially harmful. Further research on diagnostic error will inform better utilization of neuro-ophthalmologists as a resource to decrease diagnostic error.

Uveal melanoma: evaluation of extrascleral extension using thin-section MR of the eye with surface coils

PURPOSE

This study was done to evaluate the role of high-resolution magnetic resonance (MR) imaging with special surface coils in selecting the correct therapeutic approach (eye enucleation or follow-up) in patients with suspected extrascleral extension of uveal melanoma.

MATERIALS AND METHODS

This prospective study involved 12 patients with suspected extrascleral extension of uveal melanoma on orbital ultrasonography. All patients were studied with thin-section MR imaging of the eye using surface coils.

RESULTS

High-resolution MR imaging of the eye excluded extrascleral extension of disease in 8/12 patients: in 4/8 cases it revealed vascular ectasia and in the other 4/8 cases the linear hypointensity of the sclera was unbroken. Seven of these eight patients were followed up by ultrasound, which showed stability of melanoma for at least 2 years, while the last patient underwent enucleation, and the histological examination confirmed the MR diagnosis. In 4/12 patients, high-resolution MR suggested a diagnosis of extrascleral extension of melanoma, which was confirmed at histological examination after enucleation.

CONCLUSION

High-resolution MR imaging of the eye with surface coils allowed us to evaluate extrascleral extension of uveal melanoma and choose the correct therapeutic approach, avoiding unnecessary enucleation in 7/12 patients.

Neuroimaging in patients referred to a neuro-ophthalmology service: the rates of appropriateness and concordance in interpretation

OBJECTIVE

Neuroimaging studies frequently are ordered to investigate neuro-ophthalmic symptoms. When misused, these studies are expensive and time consuming. This study describes the type and frequency of neuroimaging errors in patients referred to an academic neuro-ophthalmology service and measures how frequently these neuroimaging studies were reinterpreted.

DESIGN

Prospective cohort study.

PARTICIPANTS

Eighty-four consecutive patients referred to an academic neuro-ophthalmology practice.

METHODS

From November 2009 through July 2010, 84 consecutive new patients who had undergone a neuroimaging study in the last 12 months specifically to evaluate their presenting neuro-ophthalmic symptoms were enrolled prospectively. Participants then underwent a complete neuro-ophthalmic evaluation, followed by a review of prior neuroimaging. Questions regarding appropriateness of the most recent imaging, concordance of radiologic interpretation, and re-evaluation of referring diagnoses were answered by the attending physician.

MAIN OUTCOME MEASURES

The frequency and types of errors committed in the use of neuroimaging and the frequency of reinterpretation of prereferral neuroimaging studies after neuro-ophthalmic history and examination.

RESULTS

Most study participants (84.5%; 71/84) underwent magnetic resonance imaging before referral; 15.5% (13/84) underwent only computed tomography. The rate of suboptimal neuroimaging studies was 38.1% (32/84). The 3 most common reasons for suboptimal studies were incomplete area of imaging (34.4%; 11/32), wrong study type (28.1%; 9/32), and poor image quality (21.9%; 7/32). Twenty-four of 84 subjects (28.6%) required additional neuroimaging. The authors agreed with the radiology interpretation of the prior neuroimaging studies in most patients (77.4%; 65/84). The most common anatomic locations for discordance in interpretation were the intraorbital optic nerve (35%; 7/20) and the brainstem (20%; 4/20).

CONCLUSIONS

There was a high rate of suboptimal neuroimaging studies performed in patients referred for neuro-ophthalmology examination. These findings have significant implications given the increasing attention to resource use currently and in the near future.

Imaging in neuro-ophthalmology: An overview

Advances in neuroimaging and interventional techniques have revolutionized the early diagnosis, prognosis, and treatment of neuro-ophthalmic disorders. These techniques include computed tomography (CT), magnetic resonance imaging (MRI), CT and MR angiographic techniques, catheter digital subtraction angiography, functional MRI, positron emission tomography, and single photon emission computed tomography. In this review, the value of current techniques in the diagnosis, localization, and treatment of various neuro-ophthalmic disorders is described.

Imaging for neuro-ophthalmic and orbital disease - a review

A literature review was performed by content experts in neuro-ophthalmology and neuroradiology using a systematic English-language Medline search (1994-2008) limited to articles with relevance to neuro-ophthalmic and orbital imaging. The information covered in this review includes: (i) the basic mechanics, indications and contraindications for cranial and orbital computed tomography and magnetic resonance (MR) imaging; (ii) the utility and indications for intravenous contrast, (iii) the use of specific MR sequences; (iv) the techniques and ophthalmic indications for computed tomography/MR angiography and venography; and (v) the techniques and indications for functional MR imaging, positron emission tomography scanning and single photon emission computed tomography. Throughout the review accurate and timely communication with the neuroradiologist regarding the clinical findings and suspected location of lesions is emphasized so as to optimize the ordering and interpretation of imaging studies for the ophthalmologist.

Imaging for neuro-ophthalmic and orbital disease

PURPOSE

To provide an update on imaging of the brain and orbit for ophthalmologists.

DESIGN

Literature review.

METHODS

A systematic English-language medline search and summary of recent literature on imaging of brain and orbit was performed.

RESULTS

Computed tomography and magnetic resonance (MR) scanning are the mainstays for the evaluation of most disorders involving the brain and orbit. Computed tomography angiography and magnetic resonance angiography are relatively newer applications that are useful for the evaluation of arterial and venous disorders. Special sequences such as fat suppression and fluid attenuation inversion recovery are useful techniques for specific ophthalmic indications. Diffusion weighted imaging and perfusion-weighted imaging are improving the evaluation of acute stroke. Functional MRI, positron emission tomography scanning and single photon emission computed tomography may provide useful information regarding brain or tumor metabolism. Magnetic resonance spectroscopy has expanded our knowledge of brain function. Newer imaging studies have improved our diagnostic abilities on many fronts, including new sequences, new applications of imaging studies, and functional imaging of brain.

CONCLUSION

New imaging techniques for brain and orbit have an increased potential for improving diagnostic yield. Accurate and timely communication with the neuroradiologist can optimize the prescription and interpretation of imaging in ophthalmology.