Tuberous sclerosis complex is an autosomal dominant disorder that often causes refractory seizures. The presence of multiple lesions makes it difficult to identify a single lesion responsible for the epilepsy. Our purpose is to assess the single-voxel proton spectroscopic findings of the tubers in 11 children with tuberous sclerosis complex. Prior to age 4 years, all of the patients had presented with epileptic seizures and multiple bilateral tubers in magnetic resonance images. Single-voxel proton spectroscopy was performed from the tubers especially showing epileptogenic activity using both the long and short echo time and in 14 controls. The results were analyzed using the Mann-Whitney U-test. Compared with the control group, the spectroscopic findings of tubers were characterized by decreased N-acetylaspartate to creatine ratios (1.43 +/- 0.33; P < .001) in both the long and short echo time spectra, increased choline to creatine ratios (0.91 +/- 0.082; P < .05), and myo-inositol to creatine ratios (0.97 +/- 0.19; P < .01) in the short echo time spectra. A lactate peak was detected in the regions corresponding to an epileptic focus on electroencephalography in six patients. Single-voxel proton spectroscopy could be a useful noninvasive method to evaluate epileptogenic tubers.