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Chiari 1 malformation with optic disc drusen.

Ozge Sarac1, Mehtap Caglayan2, Pinar Kosekahya3

  • 1Ataturk Training and Research Hospital, Department of Ophthalmology, Ankara, Turkey.

Neuro-Ophthalmology (Aeolus Press)
|July 26, 2018
PubMed
Summary

In patients with Chiari Malformation Type 1 (CM 1), pseudopapilledema can mimic papilledema. Differentiating these conditions is crucial to avoid unnecessary interventions.

Keywords:
Chiari 1 malformationoptic disc drusenpapilledema

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Area of Science:

  • Ophthalmology
  • Neurology
  • Medical Imaging

Background:

  • Chiari Malformation Type 1 (CM 1) is a condition where brain tissue extends into the spinal canal.
  • Papilledema, or optic nerve swelling, requires careful diagnosis and management.
  • Distinguishing true papilledema from pseudopapilledema is clinically significant.

Observation:

  • A 32-year-old female with CM 1 presented with symptoms suggestive of papilledema.
  • Ophthalmologic examination, including visual acuity and optic nerve function tests, was normal.
  • Fundoscopy showed bilateral irregular optic nerve heads with blurred margins.

Findings:

  • B-scan ultrasonography (USG) and Spectral Domain Optical Coherence Tomography (SD-OCT) were utilized for detailed optic nerve head assessment.
  • Imaging results led to a diagnosis of optic nerve drusen (ODD) in both eyes.
  • The observed optic nerve head appearance was consistent with pseudopapilledema, not true papilledema.

Implications:

  • This case highlights the importance of considering pseudopapilledema in CM 1 patients presenting with optic nerve head abnormalities.
  • Accurate differentiation prevents misdiagnosis of papilledema.
  • Avoiding misdiagnosis can spare patients from unnecessary and potentially invasive diagnostic or therapeutic procedures.