Etiology

Infection

• Encephalitis (see Encephalitis, [[Encephalitis]])
• xxx
• xxx

Metabolic Disorders

• Hypernatremia (see Hypernatremia, [[Hypernatremia]])
• Hypoglycemia (see Hypoglycemia, [[Hypoglycemia]])

Other

• Anti-Epileptic Drug Withdrawal
  • Pregabalin (Lyrica) (see Pregabalin, [[Pregabalin]]) Withdrawal
• Cytokine Release Syndrome (see Cytokine Release Syndrome, [[Cytokine Release Syndrome]])
• High-Altitude Cerebral Edema (HACE) (see

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Physiology

• Transient Lesions Involving the Splenium of the Corpus Callosum

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Diagnosis

Brain MRI

• Round-Shaped Lesion Centered in the Splenium of the Corpus Callosum: disappears after a variable lapse
  • Diffusion studies reveal DW hypersignal with low ADC values (consistent with cytotoxic edema)
  • Only high altitude cerebral edema-related cases and one patient with pregabalin withdrawal showed high ADC values (consistent with vasogenic edema)

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Clinical Manifestations

Neurologic Manifestations

• Non-Specific: absence of neurologic evidence of callosal disconnection

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Treatment

• Correction of Underlying Disorder/Supportive Care: most cases have a complete resolution after a variable lapse

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References

• Reversible splenial lesion syndrome (RESLES): what’s in a name? J Neuroimaging. 2011 Apr;21(2):e1-14. doi: 10.1111/j.1552-6569.2008.00279.x [MEDLINE]