INTRODUCTIONRadiologists may encounter bilaterally symmetrical abnormalities of the basal ganglia on magnetic resonance imaging (MRI), typically in the context of diffuse systemic, toxic or metabolic diseases. A systematic approach and broad knowledge of pathology causing this uncommon group of conditions would be useful.

MATERIALS AND METHODSThis review uses illustrative images to highlight metabolic conditions, such as Leigh's syndrome, citrullinaemia, hypoglycaemia or carbon monoxide poisoning, as well as other causes of bilateral basal ganglia lesions such as osmotic myelinolysis, deep cerebral venous thrombosis and Creutzfeldt-Jakob disease.

RESULTSCareful assessment of radiological findings outside the basal ganglia, such as involvement of the cortex, white matter, thalamus and pons, together with clinical correlation, may be helpful in narrowing the differential diagnosis, and directing further radiological, biochemical or genetic investigations. Recent advances in MR technology have resulted in newer techniques including diffusion-weighted (DW) MR imaging and MR spectroscopy (MRS); these may be helpful if appropriately used.

CONCLUSIONSAbnormal MRI findings in the basal ganglia should not be interpreted in isolation. A systematic approach including DW MR imaging, MRS, and a broad knowledge of diffuse systemic, toxic or metabolic diseases is helpful.

Basal Ganglia Diseases ; diagnosis ; diagnostic imaging ; physiopathology ; Brain Diseases, Metabolic ; diagnosis ; diagnostic imaging ; Diagnosis, Differential ; Humans ; Magnetic Resonance Imaging ; Radiography

A previously healthy 16-month-old Korean girl with symptoms of fever, vomiting, and generalized tonic seizure was diagnosed to have Group D non-typhoid Salmonella meningitis. The patient was treated with ceftriaxone (100 mg/kg/day) and amikin (22.5 mg/kg/day) initially and ciprofloxacin (30 mg/kg/day) was added later because of clinical deterioration and disseminated intravascular coagulation. Brain CT performed on the second day showed a well-demarcated low density lesion in the right lentiform nucleus and both caudate nuclei, without evidence of increased intracranial pressure. MRI performed on the 11th day confirmed CT scan findings as well as right subdural fluid collection, brain atrophy, and ventriculomegaly. She underwent subdural drainage and later ventriculo-peritoneal shunt operation. Despite receiving intensive treatment, she still has severe neurologic sequelae. Our case shows that infarctions of basal ganglia and thalami are not specific for tuberculous meningitis and that meningitis complicated by infarction is indicative of grave prognosis.
Basal Ganglia Diseases/radiography ; Basal Ganglia Diseases/pathology ; Basal Ganglia Diseases/complications ; Basal Ganglia Diseases/cerebrospinal fluid ; Brain/radiography ; Brain/pathology ; Case Report ; Cerebral Infarction/radiography ; Cerebral Infarction/pathology ; Cerebral Infarction/complications* ; Cerebral Infarction/cerebrospinal fluid ; Female ; Follow-Up Studies ; Human ; Infant ; Magnetic Resonance Imaging ; Meningitis, Bacterial/radiography ; Meningitis, Bacterial/pathology ; Meningitis, Bacterial/complications* ; Meningitis, Bacterial/cerebrospinal fluid ; Salmonella Infections/complications* ; Tomography, X-Ray Computed/methods