BACKGROUND: Sandhoff disease is an autosomal recessive disorder caused by β-hexosaminidase deficiency in which the ganglioside GM2 and other glycolipids accumulate intracellularly within lysosomes. This process results in progressive motor neuron manifestations, death from respiratory failure and infections in infantiles. CASE REPORT: This report presents a 22-month-old girl with infantile type Sandhoff disease that was hospitalized for generalized seizures and psychomotor retardation. She was diagnosed with a genetically proven novel mutation and by demonstrating it's specific imaging findings. CONCLUSIONS: Determination of spesific changes in neuroimaging which are initial findings for GM2 gangliosidosis is important from the point of diagnosis and follow-up in infants suspected of having a neurodegenerative disease.