Distinguishing Papilledema from Pseudopapilledema

Educational Objectives

The goal of this program is to improve diagnosis of papilledema. After hearing and assimilating this program, the clinician will be better able to:

1. Use patient history, physical examination, and ancillary testing to distinguish between papilledema and pseudopapilledema.

Summary

Causes of pseudopapilledema: optic disc drusen is most common; drusen often start out buried and gradually emerge to the surface over time; drusen may not be visible in younger people; tilted optic nerves may be seen, especially with myopia; crowded optic nerves may be seen in people with hyperopia; congenitally anomalous optic nerves may be misidentified

History and physical examination: history — most people present with headaches; postural and nocturnal headaches are indicative of increased ICP; ask about nausea, vomiting, pulsatile tinnitus, and transient visual obscurations; identify risk factors for increased ICP (eg, history of diplopia, focal neurologic problems, and level of risk for idiopathic intracranial hypertension [IH]); examination — look for obscuration of vessels over the margin of the disc (suggests that the axons overlying the vessels are causing the swelling), peripapillary hemorrhages, disc elevation, congestion of the vessels, and disc hyperemia; spontaneous venous pulsation is particularly important to identify; look at the central retinal veins as they enter the disc; pulsations are visible in the majority of people, although they require a 90 D lens of the slit lamp or a direct ophthalmoscope (cannot be seen with an indirect ophthalmoscope); spontaneous venous pulsations are absent in all people with elevated ICP and present in 90% of people with normal ICP; therefore, their presence with disc swelling rules out ICH

Ancillary tests

Ultrasonography: traditionally used since the 1980s, when the 30-degree test was used to identify distention of the nerve sheath around the optic nerve; also used to rule out drusen; 30-degree test has a sensitivity of ≈68% and specificity of ≈54% for elevated ICP; ultrasonography is good for identifying calcified disc drusen, but early drusen are not calcified and may not be distinguishable from true papilledema

Autofluorescence: identifies superficial disc drusen with sensitivity of ≈100%, but deep or buried drusen appear similar to papilledema

Fluorescein angiography: drusen stain with fluorescein but do not grow; buried disc drusen may not be visible; leakage is typically seen with papilledema and increases over time, and this test has an accuracy of 97% for distinguishing papilledema from pseudopapilledema in children; requires expertise in distinguishing features on fluorescein

Optical coherence tomography (OCT): retinal nerve fiber layer (RNFL) thickness — generally greater with papilledema than with pseudopapilledema, but considerable overlap exists between the conditions; opening in Bruch membrane — appears to be wider with papilledema, but no precise cutoff exists; Bruch membrane often has a forward-bowed appearance toward the inside of the eye with papilledema; multivariate analysis in children (Thompson et al [2018]) found that the combination of RNFL thickness and opening in Bruch membrane has relatively high accuracy for distinguishing true papilledema from pseudopapilledema; identification of drusen — identifying specific features is difficult; areas of hyporeflective centers with hyperreflective rims strongly indicate drusen; en face OCT — choroidal folds (wrinkles in the inner retinal layer) are diagnostic for true papilledema; however, their absence does not rule out papilledema

Indications for imaging: imaging is not recommended if the patient is asymptomatic and has multiple features of disc drusen; workup for papilledema with neuroimaging and lumbar puncture is recommended if the patient has multiple features of disc drusen and symptoms of ICH; observation is recommended if no drusen are present and patient is asymptomatic (workup should be done if changes occur); if no drusen are present and patient is symptomatic, assume papilledema is present and proceed with a workup

Readings

Chang MY, Velez FG, Demer JL, et al. Accuracy of diagnostic imaging modalities for classifying pediatric eyes as papilledema versus pseudopapilledema. Ophthalmology. 2017;124(12):1839-1848. doi:10.1016/j.ophtha.2017.06.016; Choudhari NS, Raman R, George R. Interrelationship between optic disc edema, spontaneous venous pulsation and intracranial pressure. Indian J Ophthalmol. 2009;57(5):404-406. doi:10.4103/0301-4738.55061; Thompson AC, Bhatti MT, El-Dairi MA. Bruch's membrane opening on optical coherence tomography in pediatric papilledema and pseudopapilledema. J AAPOS. 2018;22(1):38-43.e3. doi:10.1016/j.jaapos.2017.09.003.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Borchert was recorded at the USC Department of Ophthalmology Winter Symposium, held December 9, 2023, in Los Angeles, CA, and presented by the Keck School of Medicine of the University of Southern California. For information on future CME activities from this presenter, please visit https://keckusc.cloud-cme.com. Audio Digest thanks the speakers and the Keck School of Medicine of the University of Southern California for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0.50 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0.50 CE contact hours.

Lecture ID:

OP620601

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.