Broadening the differential for bilateral globus pallidus MRI T2 hyperintense lesions beyond  carbon monoxide poisoning.

Bilateral symmetric lesions of areas of the brain supplied by a perforating arterial branches (internal capsule, basal ganglia and thalamus) are rare and specifically bilateral globus pallidus lesions are even rarer.They have been associated with various conditions, but most commonly its a pathognomonic sign of carbon monoxide poisoning.There is not much evidence in the literature for the combination of drug abuse resulting in similar imaging presentation.

Case series of 5 patients seen in one academic hospital presenting with acute bilateral globus pallidus  lesions over six months.

All five patients were found unresponsive after illicit drug use and had abused cocaine, with other substances, and found to have bilateral globus pallidus lesions T2 intense on MRI. Most commonly, it was cocaine with opiates (3 patients), one with cocaine and levamisole, and one with cocaine only (though limited toxicology screen). Clinical presentations early in the course ranged from myoclonus to additional ischemic lesions causing cortical blindness,but all had some degree of cognitive impairment.

We found that use of cocaine, typically with other illicit drugs, can present a similar imaging presentation as would be seen in carbon monoxide poisoning. Mechanism may be from hypo ventilation and additional vasospasm selectively impacting the metabolically high demand basal ganglia and in particular globus pallidus, though etiology remains uncertain.