File:PMC4833782 415 2015 7905 Fig1 HTML.png

English: Fig1: To analyze the cerebral blood glucose utilization during an actual VM attack a FDG-PET was performed in a 35-year-old patient suffering from VM according to the consensus criteria [8, 9] (ECAT Exact PET Scanner, Siemens/CTI, Knoxville, USA, with a 18F-fluorodeoxyglucose [FDG]-tracer in a three-dimensional acquisition mode). During the attack the patient presented with a central positional nystagmus beating oblique (up- and leftward) and increasing in different head/body positions (supine, left ear down, right ear down). Both, nystagmus and vertiginous sensation, persisted for 72 h and resolved spontaneously without any ongoing vestibular or ocular motor dysfunction. In addition, a structural T1-weighted MRI (MPRAGE sequence, 180 slices, slice thickness = 1 mm, image matrix = 2562, TR = 9.7 ms, TE = 4 ms) was acquired in a clinical 1.5 T scanner (Siemens Vision, Erlangen, Germany). The PET image was spatially normalised using the structural MRI data and a proportional scaling was performed to adjust for differences in tracer dosage and uptake time. A two-sample t test was computed with respect to a healthy, age-matched reference sample (n = 12) acquired on the same scanner under identical conditions (supine, eyes closed). During the attack the patient showed an increased cerebral glucose metabolism bilaterally in the ventral-anterior thalamus compared to healthy volunteers at rest (p < 0.001 uncorrected). The thalamic response was localized to the prefrontal thalamic projection zone [87]. The scale reflects the z score (personal communication: C. Best, Marburg, and P. zu Eulenburg, Mainz, Germany)