www.elsevier.com/locate/ajem

American Journal of Emergency Medicine (2011) xx, xxx–xxx

Case Report

Fig. 1 Recommended technique for ocular ultrasound.

Ultrasound assessment of optic disc edema in patientswith headache

Abstract

Point-of-care ocular ultrasonography is emerging as apowerful tool to evaluate emergency department (ED)patients at risk for ophthalmologic and intracranial patho-logy. We present cases of 3 patients in whom optic discswelling was identified using ocular ultrasound. Causes foroptic disc swelling in our patients included idiopathicintracranial hypertension, secondary syphilis, and malig-nant hypertension with associated hypertensive retinopathy.Because direct visualization of the optic disc may bechallenging in an ED setting, ultrasound examination ofthe optic disc may represent an important adjunct tofundoscopy when assessing patients with headache orvisual complaints.

Point-of-care ocular ultrasonography is emerging as auseful tool for the evaluation of patients at risk forophthalmologic and intracranial pathology. Emergencyphysician–performed sonography appears to be a sensitivescreening test for various ocular conditions includingtraumatic injuries, retinal vascular insult, and retinaldetachment [1,2]. In addition, measurement of the retro-bulbar optic nerve sheath diameter (ONSD) has beeninvestigated as a means of noninvasively assessing intracra-nial pressure [2,3]. To date, however, little data exist on theperformance of point-of-care sonography to assess swellingto the optic disc. Although direct visualization using anophthalmoscope is considered the standard method ofassessing the appearance of the fundus, it may be difficultor impossible to perform this effectively, especially in an EDsetting [4-6]. Because optic disc swelling is alwaysabnormal, a reliable method to assess patients at risk forthis condition is of critical importance to the emergencyphysician. Below, we describe 3 cases in which point-of-careultrasound was used to accurately identify optic disc edemain emergency department (ED) patients with variousunderlying diagnoses.

The patient lies supine with the head in neutral positionand is instructed to close both eyes. A small amount ofultrasound gel is placed over the closed eyelid, or anonadhesive clear dressing may be placed over the eyelid to

0735-6757/$ – see front matter © 2011 Published by Elsevier Inc.

protect the eye from the gel. A high-frequency (10-13MHz) linear array transducer with a Sonosite M-Turbo(Bothell, WA) is placed lightly on the lid. We recommendthat the operator's fingers be braced on the bridge of thenose or forehead to minimize pressure on the globe (Fig. 1).The patient is instructed to look straight ahead, and theglobe is scanned in the axial plane until a clear image of theoptic disc is obtained. When the optic disc is isolated, itshould be measured from its base to maximal height (Fig.2A, normal landmarks).

A 19-year-old woman was sent to the ED by herophthalmologist for evaluation of persistent headache anddecreasing peripheral vision. She reported approximately 6months of gradually worsening blurry vision and diffuseheadache associated with nausea. She had no additionalmedical problems and denied alcohol, tobacco, and druguse. On the day of presentation, she saw her ophthalmol-ogist who noted bilateral optic disc swelling on examina-tion and referred her to the ED for further evaluation.

On evaluation, the patient's vital signs were normal. Herphysical examination was notable for morbid obesity andbilateral optic disc swelling on fundoscopy (Fig. 3). Hervisual acuity and visual fields were normal. An ocularultrasound demonstrated significant swelling of bilateraloptic discs (Fig. 2C, papilledema in idiopathic intracranialhypertension retinal base (thick arrow) with swollen opticdisc [thin arrow]). A computed tomographic scan of her head

Fig. 2 A, Normal ocular ultrasound landmarks; B, Hypertensive ischemic papillitis with retinal base [thick arrow] and swollen optic disc[thin arrow]; C, Papilledema in idiopathic intracranial hypertension with retinal base [thick arrow] and swollen optic disc [thin arrow]; D,Neurosyphilis induced optic disc swelling with height measurement.

2 Case Report

showed no abnormalities. A lumbar puncture was performedin the ED. The opening pressure was markedly elevated at 51cm, but analysis of the cerebrospinal fluid analysis wasotherwise normal. Her symptoms significantly resolved afterthe procedure. Of note, however, her optic disc swellingpersisted when she was evaluated with a repeat bedsidesonogram 24 hours later, a finding that reflects the underlyingpathophysiology of papilledema as a consequence ofimpairment of retrograde axoplasmic transport within the

Fig. 3 Fundoscopy of optic disc edema demonstrating blurreddisc margins.

optic nerve rather than a direct result of the hydrostaticpressure of the cerebrospinal fluid (CSF) on the nerve head.

The patient was diagnosed with idiopathic intracranialhypertension (IIH) and admitted to the hospital for furthermanagement. Her pain was controlled, and she was startedon acetazolamide and topiramate. Her headache symptomsimproved, and on follow-up with her ophthalmologist3 months later, her papilledema had entirely resolved.

A 36-year-old man with no prior medical history wastransferred to our ED from a community clinic to beevaluated for hypertension. He reported several weeks ofheadache and blurry vision and had a blood pressure of 235/140 at triage. He denied chest pain, shortness of breath, orother symptoms. He smoked cigarettes and drank alcoholoccasionally but denied illicit drug use.

On further evaluation, a repeat blood pressure measure-ment remained elevated at 198/131, but vital signs wereotherwise normal. His physical examination was unre-markable with the exception of bilateral optic disc swellingnoted on fundoscopy. Ocular ultrasound demonstratedsignificant swelling of both optic Retinal base discs withthe right eye more severely affected (Fig. 2B, [thick arrow]with swollen optic disc [thin arrow]).

The patient was admitted to the hospital for bloodpressure control. A subsequent noncontrast computedtomographic scan of the brain was unremarkable. Theophthalmology service evaluated the patient and confirmedexamination findings consistent with severe hypertensive

3Case Report

retinopathy. The patient's blood pressure was controlled withintravenous and oral medications during his admission. Hewas ultimately discharged home on oral blood pressureagents but was lost to follow-up before further outpatientworkup for his hypertension could be undertaken.

A 41-year-old man with HIV was evaluated in our ED for1 day of cloudiness and “darkening” of the peripheral visionin his right eye. He denied diplopia, flashing lights, floaters,headache, fevers, neck stiffness, focal weakness, or associ-ated trauma. He had been diagnosed with HIV 3 years priorand had started antiretroviral therapy 6 weeks before theonset of his symptoms. He had no coexisting medicalproblems and denied tobacco, alcohol, and drug use.

On initial evaluation in the ED, the patient's vital signs andgeneral physical examination were normal. His visual acuity,visual fields, intraocular pressures, extraocular movements,and pupils were normal. No abnormalities were noted in theanterior segment of either eye; however, the optic discs werenot well seen on initial evaluation in the ED. Point-of-caresonography revealed significant swelling of both optic discs.The findings were more severe in the right eye in which theapex of the disc was noted to bulge anteriorly approximately1.5 mm relative to the surface of the retina (Fig. 2D).

A subsequent magnetic resonance imaging confirmedbilateral optic disc edema, but no abnormal findings werenoted in the brain. A lumbar puncture yielded spinal fluidcontaining 10 white blood cells per high-power field, 15 redblood cells per high-power field, glucose of 52, and totalprotein of 57. The opening pressure was normal at 14 cm.Serum and CSF cryptococcal antigen tests were negative.The gram stain and bacterial culture of the CSF were bothnegative; however, CSF Venereal Disease Research Labo-ratory test as well as serum rapid plasma reagin (titer 256:1)and serum treponemal antibody tests were positive. Thepatient was diagnosed with neurosyphilis with associatedpapillitis. He was treated with a 5-week course of penicillin.On follow-up with neurology and ophthalmology, the patienthad no further symptoms and was noted to have resolution ofthe optic disc swelling in both eyes.

As the cases above illustrate, point-of-care ocularultrasonography can be a useful diagnostic tool for assessingswelling of the optic disc from a variety of causes. In an EDsetting, numerous obstacles may prevent an accurateassessment of the appearance of the optic disc using atraditional ophthalmoscope. Thus, we believe that thetechnique described above may prove to be a valuableadjunct to the standard ocular examination.

A rich differential diagnosis exists for the underlyingcauses of optic disc edema; however, of greatest clinicalimportance to the emergency physician is the ability to detectelevated intracranial pressure (ICP), either from an intracra-nial mass lesion or from IIH. The presence of disc swellingdemands prompt subsequent evaluation, usually withneuroimaging and a lumbar puncture.

When optic disc swelling is bilateral and caused byelevated ICP, it is correctly termed papilledema. As

illustrated above, disc edema can result from other causesas well, specifically ischemia caused by malignant hyperten-sion, inflammation caused by conditions such as sarcoidosisor multiple sclerosis, or with infections such as neurosyphilis.In these cases, the disc edema is referred to as “papillitis.” Ifno evidence of elevated ICP is uncovered, a search for one ofthese underlying etiologies should be undertaken.

What is the relationship between the presence of opticdisc swelling and the diameter of the retrobulbar optic nervesheath? Current literature in traumatic brain injury indicatesthat ONSD of 5.7 to 6 mm is accurate in predicting elevatedICP in both the intensive care unit setting [7] and in theED screening [8,9], although these findings did not attemptto characterize the appearance of the optic disc. Oneprospective ED and intensive care unit study comparedultrasound ONSD measurements and invasive ICP monitor-ing, showing that an ONSD of greater than 5 mm correlatedto an ICP greater than 20 mm Hg [3]. One prior ED casereport describes nerve sheath enlargement (ONSDs of 6.9and 7.1 mm) in addition to visible optic disc bulging in apatient with significantly elevated ICP due to idiopathicintracranial hypertension, suggesting a possible relationship[10]. It should be mentioned, however, that controversyexists as to the reliability of the technique used to measurethe ONSD in these studies [11,12]. Thus, any relationshipbetween sonographic measurements of ONSD and thepresence of optic disc swelling remains an open question.

One final point deserved mention: The degree of swellingvisualized on bedside sonography that represents trueunderlying pathology has yet to be determined. Our clinicalexperience suggests that the optic disc is visible in manyhealthy patients but appears significantly smaller than in anypatients described present. We recommend that anysignificant degree of disc swelling be further referred forexpert evaluation if uncertainty exists, although literature inthe ophthalmologic journals suggests that ultrasonographicmeasurements may accurately assess the presence of opticdisc swelling when compared with the criterion standard ofmeasurement, confocal scanning laser ophthalmoscopemeasurements [13].

Bedside ultrasonography appears to be a promisingmodality to improve clinical examination skills in evalu-ating ocular pathology in the ED. More study is needed todetermine physician accuracy and test characteristics ofbedside ultrasound in detecting optic disc swelling.However, because direct visualization of the optic discmay be challenging in an ED setting, ultrasound examina-tion of the optic disc may represent an important adjunct tofundoscopy when assessing patients with headache orvisual complaints.

Siri Daulaire MDDepartment of Emergency Medicine

Rhode Island HospitalProvidence, RI

E-mail address: siri.daulaire@gmail.com

4 Case Report

Lauren Fine MDDepartment of Emergency Medicine

Alameda County Medical CenterOakland, CA

Margaret Salmon MDDepartment of Emergency Medicine

University of California at San Francisco Medical CenterSan Francisco, CA

Catherine Cummings MDOtto Liebmann MD

Department of Emergency MedicineRhode Island Hospital

Providence, RI

Sachita Shah MD, RDMSDivision of Emergency Medicine

Harborview Medical CenterSeattle, WA

Nathan Teismann MDDepartment of Emergency Medicine

University of California at San Francisco Medical CenterSan Francisco, CA

doi:10.1016/j.ajem.2011.06.030

References

[1] Shinar Z, Chan L, Orlinsky M. Use of ocular ultrasound for theevaluation of retinal detachment. J Em Med 2011;40(1):53-7.

[2] Blaivas M, Theodoro D, Sierzinski PR. A study of bedside ocularultrasonography in the emergency department. Acad Emerg Med2002;9(8):791-9.

[3] Kimberly HH, Shah S, Marill K, Noble V. Correlation of optic nervesheath diameter with direct measurement of intracranial pressure. AcadEmerg Med 2008;15(2):201-4.

[4] Wu EH, Fagan MJ, Reinert SE, Diaz JA. Self-confidence andperceived utility of the physical examination: a comparison of medicalstudents, residents, and faculty internists. J Gen Intern Med 2007;22(12):1725-30.

[5] Roberts E, Morgan R, King D, Clerkin L. Funduscopy: a forgotten art?Postgrad Med J 1999;75:282-4.

[6] Bruce B, Lamirel C, Wright D, et al. Nonmydriatic ocular fundusphotography in the emergency department. N Engl J Med 2011;364(4):387-8.

[7] Soldatos T, Karakitsos D, Chatzimichail K, Papathanasiou M,Gouliamos A, Karabanis A. Optic nerve sonography in the diagnosisevaluation of adult brain injury. Crit Care 2008;12(3).

[8] Tayal VS, Neulander M, Norton HJ, et al. Emergency departmentsonographic measurement of optic nerve sheath diameter to detectfindings of increased intracranial pressure in adult head injury patients.Ann Emerg Med 2007;49(4):508-14.

[9] Tsung JW, Blaivas M, Cooper A, Levick NR. A rapid noninvasivemethod of detecting elevated intracranial pressure using bedside ocularultrasound: application to 3 cases of head trauma in the pediatricemergency department. Ped Emer Care 2005;21(2):94-7.

[10] Stone MB. Case report: ultrasound diagnosis of papilledema andincreased intracranial pressure in pseudotumor cerebri. Am J Em Med2009;27(3):376.e1-2.

[11] Blehar DJ, Gaspari RJ, Montoya A, Calderon R. Correlation of visualaxis measurements of the optic nerve sheath diameter. J UltrasoundMed 2008;27:407-11.

[12] Copetti R, Cattarossi L. Optic nerve ultrasound: artifacts and realimages. Intensive Care Med 2009;35(8):1488-9.

[13] Tamburelli C, Salgarello T, Caputo CG, Giudiceandrea A, Scullica L.Ultrasonographic evaluation of optic disc swelling: comparison withCSLO in idiopathic intracranial hypertension. IOVS 2000;41(10):2960-6.