Effect of General Anesthesia on MR Optic Nerve Sheath Diameter in the Pediatric Population

Israel Cohen, Matan Kraus, Gahl Greenberg, Chen Hoffmann, Shai Shrot*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Background: Papilledema is thought to be the hallmark sign of increased intracranial pressure (ICP). Distension of the subarachnoid space within the optic nerve sheath is also commonly reported in MR studies as an indirect sign of increased ICP. Hypothesis: General anesthesia and positive pressure ventilation might result in changes in optic sheath diameter (OSD) observed on clinical brain MRI. Study Type: Retrospective. Population: One hundred forty-five patients (154 MRI scans, 7.3 years ± 5.1); 97 studies in the anesthesia group (4.4 years ± 3.4) of which 22 had papilledema, and 57 in the non-anesthesia group (12.3 years ± 3.2), of which 28 had papilledema. Field Strength/Sequence: 1.5T or 3.0T volumetric T2 images. T2 images were obtained from different vendors. Assessment: OSD, optic nerve diameter (OND), and peri-optic cerebrospinal fluid (CSF) were measured manually on T2-weighted MR images for various population subgroups (with and without anesthesia; with or without papilledema). The correlation between these measurements and the clinical diagnosis of papilledema was evaluated via receiver operating characteristic (ROC) analysis. Statistical Tests: Chi-square test; Mann–Whitney Test; Spearman's test and ROCs; Interclass correlation coefficient, P = 0.05. Results: General anesthesia resulted in significantly larger mean OSD in patients with or without papilledema (7.3 ± 1.0 mm vs. 6.1 ± 1.1 mm and 6.7 ± 1.0 mm vs. 5.4 ± 0.9 mm, respectively). In the non-anesthesia group, the average OSD values (6.1 ± 1.1 mm) were significantly higher in papilledema patients compared to non-papilledema patients (5.4 ± 0.9 mm), with larger peri-optic CSF rim (1.6 ± 0.4 mm vs. 1.3 ± 0.3 mm). In the anesthesia group, OND was significantly larger in papilledema patients (3.4 ± 0.4 mm vs. 3.1 ± 0.5 mm), though the average peri-optic CSF rim did not reach a significance in papilledema compared with non-papilledema patients (2.0 ± 0.3 mm vs. 1.8 ± 0.4 mm, P = 0.06). In patients with general anesthesia, peri-optic CSF rim had a limited correlation with increased ICP. Data Conclusion: In the pediatric population, imaging findings of increased OSD on brain MRI might be related to general anesthesia rather than increased ICP. The interpretation of optic nerve sheath distention should be reported cautiously in conjunction with anesthesia status, especially in the pediatric population. Evidence Level: 4. Technical Efficacy: 5.

Original languageEnglish
Pages (from-to)1875-1881
Number of pages7
JournalJournal of Magnetic Resonance Imaging
Issue number6
StatePublished - Dec 2023


  • MRI
  • children
  • intracranial hypertension
  • pseudotumor cerebri
  • sedation


Dive into the research topics of 'Effect of General Anesthesia on MR Optic Nerve Sheath Diameter in the Pediatric Population'. Together they form a unique fingerprint.

Cite this