Reversible splenial lesion syndrome (RESLES): what's in a name?
BACKGROUND
The presence of transient lesions involving the splenium of the corpus callosum (SCC) has been described in patients with encephalitis or encephalopathy of varied etiology. We have termed it RESLES (reversible splenial lesion syndrome).


OBJECTIVE
To describe 3 additional patients (2 encephalitis, 1 hypoglycemia) and review the literature to define this syndrome, its etiology, presentation, prognosis, and possible pathophysiological mechanisms.


METHODS
Search of the MEDLINE database from 1966 through 2007. English language article titles and abstracts were screened and the appropriate articles reviewed. Additional articles cited by original references were also reviewed.


RESULTS
RESLES is caused by antiepileptic drug withdrawal, infection, high-altitude cerebral edema (HACE), or metabolic disorders (hypoglycemia and hypernatremia). Complete resolution after a variable lapse is the rule. Clinical presentation is nonspecific, without evidence of callosal disconnection syndromes. Neuroimaging shows a nonenhancing, round-shaped lesion centered in the SCC that disappears after a variable lapse. Diffusion studies reveal DW hypersignal with low ADC values, suggestive of cytotoxic edema. Only HACE-related cases and 1 patient with pregabalin withdrawal showed high ADC values, consistent with vasogenic edema.


CONCLUSIONS
RESLES is a distinct clinicoradiological syndrome of varied etiology and benign course except in those patients with an underlying severe disorder.
Garcia-Monco
Juan Carlos
JC
Servicio de Neurologia, Hospital de Galdacano, Vizcaya, Spain. hospit05@sarenet.es
Cortina
Ines Escalza
IE
Ferreira
Eva
E
Martínez
Amaia
A
Ruiz
Lara
L
Cabrera
Alberto
A
Beldarrain
Marian Gomez
MG
D000368:Aged; D000927:Anticonvulsants / Q000009:adverse effects* / Q000627:therapeutic use; D003337:Corpus Callosum / Q000473:pathology*; D004660:Encephalitis / Q000150:complications / Q000382:microbiology / Q000473:pathology*; D004827:Epilepsy / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D005260:Female; D006801:Humans; D006955:Hypernatremia / Q000150:complications / Q000473:pathology*; D007003:Hypoglycemia / Q000150:complications / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D012307:Risk Factors; D055815:Young Adult
D000927:Anticonvulsants