Validation of a protocol for manual segmentation of the thalamus on magnetic resonance imaging scans.
We present a validated protocol for manual segmentation of the thalamus on T1-weighted magnetic resonance imaging (MRI) scans using brain image analysis software. The MRI scans of five normal control subjects were randomly selected from a larger cohort recruited from Lund University Hospital and Landskrona Hospital, Sweden. MRIs were performed using a 3.0T Philips MR scanner, with an eight-channel head coil, and high resolution images were acquired using a T1-weighted turbo field echo (T1 TFE) pulse sequence, with resulting voxel size 1×1×1 mm3. Manual segmentation of the left and right thalami and volume measurement was performed on 28-30 contiguous coronal slices, using ANALYZE 11.0 software. Reliability of image analysis was performed by measuring intra-class correlations between initial segmentation and random repeated segmentation of the left and right thalami (in total 10 thalami for segmentation); inter-rater reliability was measured using volumes obtained by two other experienced tracers. Intra-class correlations for two independent raters were 0.95 and 0.98; inter-class correlations between the expert rater and two independent raters were 0.92 and 0.98. We anticipate that mapping thalamic morphology in various neuropsychiatric disorders may yield clinically useful disease-specific biomarkers.
School of Medicine, The University of Notre Dame Australia, Fremantle, Australia; Clinical Research Centre, North Metropolitan Health Service - Mental Health, Perth, Australia. Electronic address: briandiarmidpower@gmail.com.
Brian D
BD
Power
Research Centre for the Neurosciences of Ageing, Academic Unit of Psychiatry and Addiction Medicine, Australian National University Medical School, Canberra Hospital, Canberra, Australia.
Fiona A
FA
Wilkes
Research Centre for the Neurosciences of Ageing, Academic Unit of Psychiatry and Addiction Medicine, Australian National University Medical School, Canberra Hospital, Canberra, Australia.
Mitchell
M
Hunter-Dickson
Center for Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden; Diagnostic Radiology, Department of Clinical Sciences, Lund University, Lund, Sweden.
Danielle
D
van Westen
Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Lund, Sweden.
Alexander F
AF
Santillo
Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne Neuropsychiatry Centre, Melbourne, Australia.
Mark
M
Walterfang
Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Lund, Sweden.
Christer
C
Nilsson
Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne Neuropsychiatry Centre, Melbourne, Australia.
Dennis
D
Velakoulis
Research Centre for the Neurosciences of Ageing, Academic Unit of Psychiatry and Addiction Medicine, Australian National University Medical School, Canberra Hospital, Canberra, Australia.
Jeffrey C L
JC
Looi
D015415:Biomarkers; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019636:Neurodegenerative Diseases / Q000175:diagnosis*; D015203:Reproducibility of Results; D012984:Software; D013548:Sweden; D013788:Thalamus / Q000033:anatomy & histology*
D015415:Biomarkers
Biomarker; Dementia; Neurodegenerative disorder; Neuroimaging; Neuropsychiatry; Thalamus