Biological Characteristics of a Cerebellar Mass Regrowing after Removal in a Patient with Lhermitte-Duclos Disease: Emission Tomography Studies
A 17-year-old man underwent a subtotal removal of a cerebellar mass lesion (Lhermitte-Duclos disease) via craniectomy []. Thirteen years later, the patient presented with headaches. Neurological examination showed a slightly ataxic gait. MRI revealed a regrowing mass lesion with an abnormal laminated pattern of cortical architecture in the left cerebellar hemisphere, extending to the vermis (fig. ).\nBrain blood flow and metabolic rate of oxygen were calculated by the steady-state method using a PET scanner and 15O-gas []. Both 99mTc-ECD and 123I-iomazenil SPECT studies were performed at 3 and 7 days after PET, respectively, using the same procedures applied in previous studies [, ]. The study protocol was approved by the local ethics committee. Written informed consent was obtained from the subject prior to undergoing these studies.\nIn the cerebellar region, increases in both blood flow and metabolic rate of oxygen were detected on 15O-gas PET imaging (fig. ). While the lesion exhibited hyperactivity on 99mTc-ECD SPECT imaging, where the contrast was similar to that of blood flow PET imaging, 123I-iomazenil SPECT showed a defect in uptake within the lesion (fig. ).\nThe lesion was partially resected through a suboccipital craniectomy. Histological examination revealed typical features of Lhermitte-Duclos disease.