Spontaneous Skull Base Cerebrospinal Fluid Leaks and Their Relationship to Idiopathic Intracranial Hypertension

Background

The association between spontaneous skull base cerebrospinal fluid (CSF) leaks and idiopathic intracranial hypertension (IIH) has been suggested, but its significance remains unclear.

Objective

To estimate the prevalence of IIH in spontaneous skull base CSF leak patients.

Methods

Systematic collection of demographics, neuro-ophthalmic and magnetic resonance imaging evaluation of spontaneous skull base CSF leak patients seen pre- and post-leak repair in one neuro-ophthalmology service. Patients with preexisting IIH were diagnosed with definite IIH if adequate documentation was provided; otherwise, they were categorized with presumed IIH. Classic radiographic signs of intracranial hypertension and bilateral transverse venous sinus stenosis were recorded.

Results

Thirty six patients were included (age [interquartile range]: 50 [45;54] years; 94% women; body mass index: 36.8 [30.5;39.9] kg/m2), among whom six (16.7%, [95% confidence interval, CI]: [6.4;32.8]) had a preexisting diagnosis of definite or presumed IIH. Of the remaining 30 patients, four (13.3%, 95%CI: [3.8;30.7]) had optic nerve head changes suggesting previously undiagnosed IIH, while one was newly diagnosed with definite IIH at initial consultation. One out of 29 patients with normal findings of the optic nerve head at presentation developed new onset papilledema following surgery (3.4%, 95%CI: [0.1;17.8]) and was ultimately diagnosed with definite IIH. Overall, the prevalence of definite IIH was 19.4% (95%CI: [8.2;36.0]).

Conclusion

Striking demographic overlap exists between IIH patients and those with spontaneous CSF leak. Definite IIH was present in approximately 20% of our patients. However, its true prevalence is likely higher than identified by using classic criteria. We therefore hypothesize that an active CSF leak serves as an auto-diversion for CSF, thereby “treating” the intracranial hypertension and eliminating characteristic signs and symptoms at initial presentation.

Artificial Intelligence to Detect Papilledema from Ocular Fundus Photographs

BACKGROUND

Nonophthalmologist physicians do not confidently perform direct ophthalmoscopy. The use of artificial intelligence to detect papilledema and other optic-disk abnormalities from fundus photographs has not been well studied.

METHODS

We trained, validated, and externally tested a deep-learning system to classify optic disks as being normal or having papilledema or other abnormalities from 15,846 retrospectively collected ocular fundus photographs that had been obtained with pharmacologic pupillary dilation and various digital cameras in persons from multiple ethnic populations. Of these photographs, 14,341 from 19 sites in 11 countries were used for training and validation, and 1505 photographs from 5 other sites were used for external testing. Performance at classifying the optic-disk appearance was evaluated by calculating the area under the receiver-operating-characteristic curve (AUC), sensitivity, and specificity, as compared with a reference standard of clinical diagnoses by neuro-ophthalmologists.

RESULTS

The training and validation data sets from 6779 patients included 14,341 photographs: 9156 of normal disks, 2148 of disks with papilledema, and 3037 of disks with other abnormalities. The percentage classified as being normal ranged across sites from 9.8 to 100%; the percentage classified as having papilledema ranged across sites from zero to 59.5%. In the validation set, the system discriminated disks with papilledema from normal disks and disks with nonpapilledema abnormalities with an AUC of 0.99 (95% confidence interval [CI], 0.98 to 0.99) and normal from abnormal disks with an AUC of 0.99 (95% CI, 0.99 to 0.99). In the external-testing data set of 1505 photographs, the system had an AUC for the detection of papilledema of 0.96 (95% CI, 0.95 to 0.97), a sensitivity of 96.4% (95% CI, 93.9 to 98.3), and a specificity of 84.7% (95% CI, 82.3 to 87.1).

CONCLUSIONS

A deep-learning system using fundus photographs with pharmacologically dilated pupils differentiated among optic disks with papilledema, normal disks, and disks with nonpapilledema abnormalities. (Funded by the Singapore National Medical Research Council and the SingHealth Duke-NUS Ophthalmology and Visual Sciences Academic Clinical Program.).

Lack of Relationship between Central Corneal Thickness and Papilloedema in Idiopathic Intracranial Hypertension

Translaminar pressure gradient abnormalities have been implicated in the pathogenesis and progression of glaucoma. A "reversed" translaminar pressure gradient may be related to papilloedema severity in idiopathic intracranial hypertension. Central corneal thickness is related to intraocular pressure measurements and, by extension, to translaminar pressure gradients. We evaluated if central corneal thickness could be a marker of worse papilloedema due to altered translaminar pressure gradients in patients with idiopathic intracranial hypertension. We found that central corneal thickness was not related to the severity of papilloedema in idiopathic intracranial hypertension.

Diagnostic Errors in Initial Misdiagnosis of Optic Nerve Sheath Meningiomas

Importance

Diagnostic errors can lead to the initial misdiagnosis of optic nerve sheath meningiomas (ONSM), which can lead to vision loss.

Objective

To identify factors contributing to the initial misdiagnosis of ONSM.

Design, Setting, and Participants

We retrospectively reviewed 35 of 39 patients with unilateral ONSM (89.7%) who were seen in the tertiary neuro-ophthalmology practice at Emory University School of Medicine between January 2002 and March 2017. The Diagnosis Error Evaluation and Research taxonomy tool was applied to cases with missed/delayed diagnoses.

Exposures

Evaluation in a neuro-ophthalmology clinic.

Main Outcomes and Measures

Identifying the cause of diagnostic errors for patients who initially received a misdiagnosis who were found to have ONSM.

Results

Of 35 patients with unilateral ONSM (30 women [85.7%]; mean [SD] age, 45.26 [15.73] years), 25 (71%) had a diagnosis delayed for a mean (SD) of 62.60 (89.26) months. The most common diagnostic error (19 of 25 [76%]) was clinician assessment failure (errors in hypothesis generation and weighing), followed by errors in diagnostic testing (15 of 25 [60%]). The most common initial misdiagnosis was optic neuritis (12 of 25 [48%]), followed by the failure to recognize optic neuropathy in patients with ocular disorders. Five patients who received a misdiagnosis (20%) underwent unnecessary lumbar puncture, 12 patients (48%) unnecessary laboratory tests, and 6 patients (24%) unnecessary steroid treatment. Among the 16 patients who initially received a misdiagnosis that was later correctly diagnosed at our institution, 11 (68.8%) had prior magnetic resonance imaging (MRI) results that were read as healthy; 5 (45.5%) showed ONSM but were misread by a non-neuroradiologist and 6 (54.5%) were performed incorrectly (no orbital sequence or contrast). Sixteen of the 25 patients (64%) had a poor visual outcome.

Conclusions and Relevance

Biased preestablished diagnoses, inaccurate funduscopic examinations, a failure to order the correct test (MRI brain/orbits with contrast), and a failure to correctly interpret MRI results were the most common sources of diagnostic errors and delayed diagnosis with worse visual outcomes and increased cost (more visits and tests). Easier access to neuro-ophthalmologists, improved diagnostic strategies, and education regarding neuroimaging should help prevent diagnostic errors.

Update on pediatric optic neuritis

PURPOSE OF REVIEW

To summarize recent developments in the classification, investigation and management of pediatric optic neuritis (PON).

RECENT FINDINGS

A recent surge in interest surrounding antibodies to myelin oligodendrocyte glycoprotein antibody (MOG-Ab) has instigated a paradigm shift in our assessment of children with PON. This serological marker is associated with a broad spectrum of demyelinating syndromes that are clinically and radiologically distinct from multiple sclerosis (MS) and aquaporin-4 antibody positive neuromyelitis optica spectrum disorder (AQP4+NMOSD). Optic neuritis is the most common presenting phenotype of MOG-Ab positive-associated disease (MOG+AD). MOG-Ab seropositivity is much more common in the pediatric population and it predicts a better prognosis than MS or AQP4+NMOSD, except in the subset that exhibit a recurrent phenotype.

SUMMARY

A better grasp of MOG+AD features and its natural history has facilitated more accurate risk stratification of children after a presenting episode of PON. Consequently, the initial investigation of PON has broadened to include serology, along with neuroimaging and cerebrospinal fluid analysis. Acute treatment of PON and chronic immunotherapy is also becoming better tailored to the suspected or confirmed diagnoses of MS, AQP4+NMOSD and MOG+AD.

Haemodilution and head-down tilting induce functional injury in the rat optic nerve: A model for peri-operative ischemic optic neuropathy

BACKGROUND

Mechanisms of peri-operative ischaemic optic neuropathy remain poorly understood. Both specific pre-operative and intra-operative factors have been examined by retrospective studies, but no animal model currently exists.

OBJECTIVES

To develop a rodent model of peri-operative ischaemic optic neuropathy. In rats, we performed head-down tilt and/or haemodilution, theorising that the combination damages the optic nerve.

DESIGN

Animal study.

SETTING

Laboratory.

ANIMALS

A total of 36 rats, in four groups, completed the functional examination of retina and optic nerve after the interventions.

INTERVENTIONS

Anaesthetised groups (n>8) were supine (SUP) for 5 h, head-down tilted 70° for 5 h, head-down tilted/haemodiluted for 5 h or SUP/haemodiluted for 5 h. We measured blood pressure, heart rate, intra-ocular pressure and maintained constant temperature.

MAIN OUTCOME MEASUREMENTS

Retinal function (electroretinography), scotopic threshold response (STR) (for retinal ganglion cells) and visual evoked potentials (VEP) (for transmission through the optic nerve). We imaged the optic nerve in vivo and evaluated retinal histology, apoptotic cells and glial activation in the optic nerve. Retinal and optic nerve function were followed to 14 and 28 days after experiments.

RESULTS

At 28 days in head down tilted/haemodiluted rats, negative STR decreased (about 50% amplitude reduction, P = 0.006), VEP wave N2-P3 decreased (70% amplitude reduction, P = 0.01) and P2 latency increased (35%, P = 0.003), optic discs were swollen and glial activation was present in the optic nerve. SUP/haemodiluted rats had decreases in negative STR and increased VEP latency, but no glial activation.

CONCLUSION

An injury partly resembling human ischaemic optic neuropathy can be produced in rats by combining haemodilution and head-down tilt. Significant functional changes were also present with haemodilution alone. Future studies with this partial optic nerve injury may enable understanding of mechanisms of peri-operative ischaemic optic neuropathy and could help discover preventive or treatment strategies.

Differing presenting features of idiopathic intracranial hypertension in the UK and US

AIM

Demographic factors potentially influencing the presentation and severity of idiopathic intracranial hypertension (IIH) in the US vs. UK populations include obesity and ethnicity. We aimed to compare the presenting features of IIH between populations in the UK and US tertiary referral centres, to assess what population differences exist and whether these cause different presentations and impact on visual function.

METHODS

Clinical data were collected on 243 consecutive UK IIH patients and 469 consecutive US IIH patients seen after 2012 in two tertiary centres. Visual function was defined as severe visual loss when Humphrey visual field mean deviation was <-15 dB, when Goldmann visual fields showed constriction or when visual acuity was <20/200.

RESULTS

US patients were more commonly of self-reported black race (58.9% vs. 7.1%) than UK patients, but had a similar mean body mass index (38.3 ± 0.63kg/m² UK vs. 37.7 ± 0.42kg/m² US; p = 0.626). The UK cohort had lower presenting Frisén grade (median 1 vs. 2; p < 0.001) and severe visual loss less frequently (15.4% vs. 5%; p = 0.014), but there was no difference in mean cerebrospinal fluid-opening pressure (CSF-OP) (35.8 ± 0.88cmH₂O UK vs. 36.3 ± 0.52cmH₂O US; p = 0.582). African Americans had poorer visual outcomes compared with US whites (19.4% vs. 10% severe visual loss; p = 0.011). Visual function was weakly associated with CSF-OP (R² = 0.059; p = 0.001), which was similar between UK and US patients.

CONCLUSIONS

The UK and the US cohorts had a similar average presenting BMI. However, the worse presenting visual function in the US IIH cohort was partially attributable to differences in the black populations in the two countries.

Nonmydriatic Fundus Photography in Patients with Acute Vision Loss

Background: Acute visual loss is a common chief complaint in emergency department (ED) patients, but the scarcity of ophthalmologists in most EDs limits its evaluation. Introduction: Our objective was to evaluate whether nonmydriatic fundus photography (NMFP) in the ED helps triage patients with acute visual loss. Materials and Methods: We included 213 patients with acute visual loss evaluated in the ED with NMFP as part of the Fundus Photography versus Ophthalmoscopy Trial Outcomes in the ED studies. Demographics, referral patterns, results of NMFP, and final diagnoses were recorded. Results: A final ophthalmological diagnosis was made in 109/213 (51%) patients. NMFP allowed a definite diagnosis in 51/109 (47%) patients: 14 nonglaucomatous optic neuropathies, 10 papilledema, 13 acute retinal ischemia, 2 retinal detachments, 2 choroidal metastases, 4 maculopathies, and 6 glaucoma. In 58/109 (53%) patients, NMFP was not diagnostic even when interpreted remotely by ophthalmologists due to disorders undiagnosable with NMFP. Ophthalmology consultation was requested in 109/213 (51%) patients, 41/54 (76%) patients with abnormal NMFP versus 68/159 (43%) patients with normal NMPF (p < 0.001). Discussion: Although NMFP allowed rapid diagnosis in 51/213 (24%) patients presenting to the ED with acute visual loss, NMFP alone was not sufficient to detect all ocular diseases; ophthalmology consultation was more often requested when NMFP was abnormal. Conclusions: Our study emphasizes the limitations of teleophthalmology with NMFP in remotely detecting ocular diseases related to acute visual loss in the ED. NMFP helped triage and referral decisions and can be used to complement ophthalmology consultations in the ED.

Optic nerve appearance as a predictor of visual outcome in patients with idiopathic intracranial hypertension

BACKGROUND/AIMS

It remains unclear whether the presence of optic disc haemorrhages (ODH) or cotton wool spots (CWS) at presentation in patients with papilloedema from idiopathic intracranial hypertension (IIH) has prognostic value. The aim of this study was to determine if optic disc appearance at presentation predicts visual outcome in patients with IIH.

METHODS

Retrospective study of 708 eyes of 360 consecutive patients with IIH who had baseline optic disc photographs before or within 30 days of their diagnostic lumbar puncture and initiation of medical treatment. Optic disc photographs were independently graded by three ophthalmologists in a standardised manner. Visual function was assessed using Snellen converted to logMAR visual acuity, Humphrey mean deviation and visual field grade.

RESULTS

At least one ODH was found in 201 (28.4%) eyes, at least one CWS was found in 101 (14.3%) eyes and 88 eyes had both ODH and CWS (12.4%). At presentation, Frisén grade was associated with the presence and severity of ODH and CWS (p<0.001). ODH were associated with a worse visual acuity and CWS were associated with a worse visual field grade and mean deviation at presentation (p<0.05). Frisén grade was associated with worse visual function at presentation and final follow-up (p<0.001). Neither ODH nor CWS at presentation were associated with visual function at final follow-up when controlling for the Frisén grade.

CONCLUSIONS AND RELEVANCE

ODH and CWS at baseline are not independent predictors of final visual function in IIH when controlling for the severity of papilloedema.

Papilloedema from Dural Venous Sinus Compression by Meningiomas

Intracranial mass lesions may cause intracranial hypertension secondary to venous hypertension when they compress the dural venous sinuses (DVS) and may present with isolated papilloedema, mimicking idiopathic intracranial hypertension. We report a series of 16 patients with isolated papilloedema related to meningiomas compressing the DVS seen from 2012 to 2016 at three institutions. Correct diagnosis was delayed in 10/16 patients and treatment required a multidisciplinary approach, often with multiple sequential interventions, including combinations of acetazolamide, cerebrospinal fluid-shunt, optic nerve sheath fenestration, surgical resection of the meningioma, radiation therapy, and endovascular venous stenting. Two patients also received anticoagulation for venous thrombosis secondary to venous sinus compression.

Optical coherence tomography retinal ganglion cell complex analysis for the detection of early chiasmal compression

PURPOSE

To report patients with sellar tumors and chiasmal compression with normal visual fields, who demonstrate damage to the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) on optical coherence tomography (OCT).

METHODS

Seven patients with sellar tumors causing mass effect on the optic chiasm without definite visual field defect, but abnormal GCC are described. GCC/RNFL analyses using Cirrus-OCT were classified into centiles based on the manufacturer's reference range.

RESULTS

In seven patients with radiologic compression of the chiasm by a sellar tumor, OCT-GCC thickness detected compressive chiasmopathy before visual defects became apparent on standard automated visual field testing. Without OCT, our patients would have been labelled as having normal visual function and no evidence of compressive chiasmopathy. With only OCT-RNFL analysis, 3/7 patients would still have been labelled as having no compression of the anterior visual pathways.

CONCLUSIONS

These patients show that OCT-GCC analysis is more sensitive than visual field testing with standard automated perimetry in the detection of compressive chiasmopathy or optic neuropathy. These cases and previous studies suggest that OCT-GCC analysis may be used in addition to visual field testing to evaluate patients with lesions compressing the chiasm.

Treatment of Nonarteritic Acute Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is an event most often caused by an embolus originating in the ipsilateral carotid artery, aortic arch, or heart. CRAO may result from partial or complete occlusion of the central retinal artery (CRA), which acts as the primary blood supply to the inner neurosensory retina, and typically results in profound vision loss and permanent visual disability. No consensus has emerged regarding the optimal treatment of CRAO. All proposed treatments are of questionable efficacy and many have uncertain risk profiles. In certain circumstances, thrombolysis may be attempted as a treatment option; however, the evidence to support broad use of thrombolytics in the treatment of acute CRAO remains elusive. It is known that the risk factors that predispose to other cardiovascular and cerebrovascular events are often present in CRAO. Accordingly, identification of patients at highest risk of stroke and secondary prevention of ischemic events remains the primary focus of management. This review offers a summary of the clinical presentation, diagnosis, and prognosis of CRAO, with an emphasis on treatment options.

Acute retinal arterial ischemia

Acute retinal arterial ischemia, which includes transient monocular vision loss (TMVL), branch retinal artery occlusion (BRAO), central retinal artery occlusion (CRAO) and ophthalmic artery occlusion (OAO), is most commonly the consequence of an embolic phenomenon from the ipsilateral carotid artery, heart or aortic arch, leading to partial or complete occlusion of the central retinal artery (CRA) or its branches. Acute retinal arterial ischemia is the ocular equivalent of acute cerebral ischemia and is an ophthalmic and medical emergency. Patients with acute retinal arterial ischemia are at a high risk of having further vascular events, such as subsequent strokes and myocardial infarctions (MIs). Therefore, prompt diagnosis and urgent referral to appropriate specialists and centers is necessary for further work-up (such as brain magnetic resonance imaging with diffusion weighted imaging, vascular imaging, and cardiac monitoring and imaging) and potential treatment of an urgent etiology (e.g., carotid dissection or critical carotid artery stenosis). Since there are no proven, effective treatments to improve visual outcome following permanent retinal arterial ischemia (central or branch retinal artery occlusion), treatment must focus on secondary prevention measures to decrease the likelihood of subsequent ischemic events.

Management of Acute Retinal Ischemia: Follow the Guidelines!

Acute retinal arterial ischemia, including vascular transient monocular vision loss (TMVL) and branch (BRAO) and central retinal arterial occlusions (CRAO), are ocular and systemic emergencies requiring immediate diagnosis and treatment. Guidelines recommend the combination of urgent brain magnetic resonance imaging with diffusion-weighted imaging, vascular imaging, and clinical assessment to identify TMVL, BRAO, and CRAO patients at highest risk for recurrent stroke, facilitating early preventive treatments to reduce the risk of subsequent stroke and cardiovascular events. Because the risk of stroke is maximum within the first few days after the onset of visual loss, prompt diagnosis and triage are mandatory. Eye care professionals must make a rapid and accurate diagnosis and recognize the need for timely expert intervention by immediately referring patients with acute retinal arterial ischemia to specialized stroke centers without attempting to perform any further testing themselves. The development of local networks prompting collaboration among optometrists, ophthalmologists, and stroke neurologists should facilitate such evaluations, whether in a rapid-access transient ischemic attack clinic, in an emergency department-observation unit, or with hospitalization, depending on local resources.

Noninvasive Assessment of Intracranial Pressure Status in Idiopathic Intracranial Hypertension Using Displacement Encoding with Stimulated Echoes (DENSE) MRI: A Prospective Patient Study with Contemporaneous CSF Pressure Correlation

BACKGROUND AND PURPOSE

Intracranial pressure is estimated invasively by using lumbar puncture with CSF opening pressure measurement. This study evaluated displacement encoding with stimulated echoes (DENSE), an MR imaging technique highly sensitive to brain motion, as a noninvasive means of assessing intracranial pressure status.

MATERIALS AND METHODS

Nine patients with suspected elevated intracranial pressure and 9 healthy control subjects were included in this prospective study. Controls underwent DENSE MR imaging through the midsagittal brain. Patients underwent DENSE MR imaging followed immediately by lumbar puncture with opening pressure measurement, CSF removal, closing pressure measurement, and immediate repeat DENSE MR imaging. Phase-reconstructed images were processed producing displacement maps, and pontine displacement was calculated. Patient data were analyzed to determine the effects of measured pressure on pontine displacement. Patient and control data were analyzed to assess the effects of clinical status (pre-lumbar puncture, post-lumbar puncture, or control) on pontine displacement.

RESULTS

Patients demonstrated imaging findings suggesting chronically elevated intracranial pressure, whereas healthy control volunteers demonstrated no imaging abnormalities. All patients had elevated opening pressure (median, 36.0 cm water), decreased by the removal of CSF to a median closing pressure of 17.0 cm water. Patients pre-lumbar puncture had significantly smaller pontine displacement than they did post-lumbar puncture after CSF pressure reduction (P = .001) and compared with controls (P = .01). Post-lumbar puncture patients had statistically similar pontine displacements to controls. Measured CSF pressure in patients pre- and post-lumbar puncture correlated significantly with pontine displacement (r = 0.49; P = .04).

CONCLUSIONS

This study establishes a relationship between pontine displacement from DENSE MR imaging and measured pressure obtained contemporaneously by lumbar puncture, providing a method to noninvasively assess intracranial pressure status in idiopathic intracranial hypertension.

Fundus Photography vs. Ophthalmoscopy Outcomes in the Emergency Department (FOTO-ED) Phase III: Web-based, In-service Training of Emergency Providers

We evaluated a web-based training aimed at improving the review of fundus photography by emergency providers. 587 patients were included, 12.6% with relevant abnormalities. Emergency providers spent 31 minutes (median) training and evaluated 359 patients. Median post-test score improvement was 6 percentage points (IQR: 2-14; p = 0.06). Pre- vs. post-training, the emergency providers reviewed 45% vs. 43% of photographs; correctly identified abnormals in 67% vs. 57% of cases; and correctly identified normals in 80% vs. 84%. The Fundus photography vs. Ophthalmoscopy Trial Outcomes in the Emergency Department studies have demonstrated that emergency providers perform substantially better with fundus photography than direct ophthalmoscopy, but our web-based, in-service training did not result in further improvements at our institution.

Optic nerve head edema among patients presenting to the emergency department

OBJECTIVE

To determine the frequency of and predictive factors for optic nerve head edema (ONHE) among patients with headache, neurologic deficit, visual loss, or elevated blood pressure in the emergency department (ED).

METHODS

Cross-sectional analysis was done of patients with ONHE in the prospective Fundus Photography vs Ophthalmoscopy Trial Outcomes in the Emergency Department (FOTO-ED) study. Demographics, neuroimaging results, management, and patient disposition were collected. Patients in the ONHE and non-ONHE groups were compared with bivariate and logistic regression analyses.

RESULTS

Of 1,408 patients included, 37 (2.6%, 95% confidence interval 1.9-3.6) had ONHE (median age 31 [interquartile range 26-40] years, women 27 [73%], black 28 [76%]). ONHE was bilateral in 27 of 37 (73%). Presenting complaints were headache (18 of 37), visual loss (10 of 37), acute neurologic deficit (4 of 37), elevated blood pressure (2 of 37), and multiple (3 of 37). The most common final diagnoses were idiopathic intracranial hypertension (19 of 37), CSF shunt malfunction/infection (3 of 37), and optic neuritis (3 of 37). Multivariable logistic regression found that body mass index ≥35 kg/m² (odds ratio [OR] 1.9, p = 0.0002), younger age (OR 0.5 per 10-year increase, p < 0.0001), and visual loss (OR 5, p = 0.0002) were associated with ONHE. Patients with ONHE were more likely to be admitted (62% vs 19%), to be referred to other specialists (100% vs 54%), and to receive neuroimaging (89% vs 63%) than patients without ONHE (p < 0.001). Fundus photographs in the ED allowed initial diagnosis of ONHE for 21 of 37 (57%) patients. Detection of ONHE on ED fundus photography changed the final diagnosis for 10 patients.

CONCLUSIONS

One in 38 patients (2.6%) presenting to the ED with a chief complaint of headache, neurologic deficit, visual loss, or elevated blood pressure had ONHE. Identification of ONHE altered patient disposition and contributed to the final diagnosis, confirming the importance of funduscopic examination in the ED.