Toxic-Metabolic, Nutritional, and Medicinal- Induced Disorders of Cerebellum Nadejda Alekseeva, MD a , Jeanie McGee, DHEd, MSHS b , Roger E. Kelley, MD c , Amir Hadi Maghzi, MD d , Eduardo Gonzalez-Toledo, MD, PhD e , Alireza Minagar, MD a, * INTRODUCTION The human cerebellum is situated behind the pons and medulla within the posterior cranial fossa and is composed of 2 vastly convoluted hemispheres and a narrow medial section known as the vermis. The cerebellar vermis (derived from Latin word for worm) is situated in the corticonuclear zone of the cerebellum (Fig. 1). Three pairs of dense fiber bundles known as peduncles connect the cerebellum to the brain. Despite extensive research into the role of the cerebellum in human a Department of Psychiatry, Overton Brooks VA Medical Center, 510 East Stoner Avenue, Shreveport, LA 71101, USA; b Department of Neurology, LSU Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71103, USA; c Department of Neurology, Tulane University, 1430 Tulane Avenue, #8065, New Orleans, LA 70112, USA; d Department of Neurology, Univer- sity of California, 350 Parnassus Avenue, San Francisco, CA 94117, USA; e Department of Radi- ology, LSU Health Sciences Center, Shreveport - 1501 Kings Highway, Shreveport, LA 71103, USA * Corresponding author. LSUHSC-Shreveport, 1501 Kings Highway, Shreveport, LA 71130. E-mail address: aminag@lsuhsc.edu KEYWORDS  Cerebellum  Ataxia  Atrophy  Thiamine deficiency  Phenytoin  Ethanol KEY POINTS  A number of toxic, metabolic, nutritional, and medicinal insults may affect the cerebellum.  Acute alcohol intoxication, chronic alcoholism, anticonvulsant therapy, and thiamine defi- ciency are among the more common causes of cerebellar dysfunction.  Metabolic explanations for cerebellar dysfunction can include hypoglycemia and hypothy- roidism, as well as pronounced electrolyte disturbance.  Illicit drugs such as cocaine, heroin, and phencyclidine can result in cerebellar damage.  Poisoning with a number of agents, including carbon monoxide and insecticides, can affect the cerebellum.  Rapid assessment and management of patients with toxin- and metabolic-induced disor- ders of the cerebellum can have an important impact on outcome. Neurol Clin 32 (2014) 901–911 http://dx.doi.org/10.1016/j.ncl.2014.07.001 neurologic.theclinics.com 0733-8619/14/$ – see front matter Ó 2014 Elsevier Inc. All rights reserved.