Hugo Botha1, Jennifer L Whitwell2, Ajay Madhaven2, Matthew L Senjem3, Val Lowe2, Keith A Josephs4. 1. Department of Neurology, Mayo Clinic, Rochester, MN, USA. 2. Department of Radiology, Mayo Clinic, Rochester, MN, USA. 3. Department of Information Technology, Mayo Clinic, Rochester, MN, USA. 4. Department of Neurology, Mayo Clinic, Rochester, MN, USA. Electronic address: josephs.keith@mayo.edu.
Abstract
BACKGROUND: Some patients with progressive supranuclear palsy syndrome (PSPS) demonstrate a focal area of midbrain hypometabolism on FDG-PET scans which we call the 'pimple sign'. We assessed its association with midbrain atrophy, its reliability and its ability to differentiate PSPS from corticobasal syndrome (CBS) and multiple system atrophy (MSA). METHODS: We identified 67 patients with PSPS, CBS or MSA who had volumetric MRI as well as FDG-PET imaging. Midbrain volume was measured and expressed as a percentage of total intracranial volume. Two independent, blinded specialists rated the 'pimple sign' on FDG-PET as 'absent', 'possible' or 'definite'. Midbrain volumes were compared across these groups and reliability assessed with the kappa statistic. Sensitivity and specificity were calculated using CBS and MSA patients as controls. RESULTS: Midbrain volume was decreased in the 'definite' group compared to the 'absent' and 'possible' groups (p = 0.0036). Inter-rater reliability for the pimple sign was high (κ = 0.90). A 'definite pimple sign' had a high specificity (100%) but low sensitivity (29%) for PSPS, whilst the presence of a possible or definite sign had a sensitivity of 79%. CONCLUSION: The 'pimple sign' of PSPS is associated with midbrain atrophy, and may be helpful in differentiating PSPS from CBS and MSA.
BACKGROUND: Some patients with progressive supranuclear palsy syndrome (PSPS) demonstrate a focal area of midbrain hypometabolism on FDG-PET scans which we call the 'pimple sign'. We assessed its association with midbrain atrophy, its reliability and its ability to differentiate PSPS from corticobasal syndrome (CBS) and multiple system atrophy (MSA). METHODS: We identified 67 patients with PSPS, CBS or MSA who had volumetric MRI as well as FDG-PET imaging. Midbrain volume was measured and expressed as a percentage of total intracranial volume. Two independent, blinded specialists rated the 'pimple sign' on FDG-PET as 'absent', 'possible' or 'definite'. Midbrain volumes were compared across these groups and reliability assessed with the kappa statistic. Sensitivity and specificity were calculated using CBS and MSA patients as controls. RESULTS: Midbrain volume was decreased in the 'definite' group compared to the 'absent' and 'possible' groups (p = 0.0036). Inter-rater reliability for the pimple sign was high (κ = 0.90). A 'definite pimple sign' had a high specificity (100%) but low sensitivity (29%) for PSPS, whilst the presence of a possible or definite sign had a sensitivity of 79%. CONCLUSION: The 'pimple sign' of PSPS is associated with midbrain atrophy, and may be helpful in differentiating PSPS from CBS and MSA.
Authors: Jennifer L Whitwell; Nirubol Tosakulwong; Christopher G Schwarz; Hugo Botha; Matthew L Senjem; Anthony J Spychalla; J Eric Ahlskog; David S Knopman; Ronald C Petersen; Clifford R Jack; Val J Lowe; Keith A Josephs Journal: Mov Disord Date: 2018-11-23 Impact factor: 10.338
Authors: Keith A Josephs; Joseph R Duffy; Edythe A Strand; Mary M Machulda; Matthew L Senjem; Jeffrey L Gunter; Christopher G Schwarz; Robert I Reid; Anthony J Spychalla; Val J Lowe; Clifford R Jack; Jennifer L Whitwell Journal: Brain Date: 2014-08-11 Impact factor: 13.501
Authors: Richard M Tsai; Iryna Lobach; Jee Bang; Jennifer L Whitwell; Matthew L Senjem; Clifford R Jack; Howard Rosen; Bruce Miller; Adam L Boxer Journal: Parkinsonism Relat Disord Date: 2016-04-24 Impact factor: 4.891
Authors: Nicholas Zalewski; Hugo Botha; Jennifer L Whitwell; Val Lowe; Dennis W Dickson; Keith A Josephs Journal: J Neurol Date: 2014-02-04 Impact factor: 4.849
Authors: Jennifer L Whitwell; Chase A Stevens; Joseph R Duffy; Heather M Clark; Mary M Machulda; Edythe A Strand; Peter R Martin; Rene L Utianski; Hugo Botha; Anthony J Spychalla; Matthew L Senjem; Christopher G Schwarz; Clifford R Jack; Farwa Ali; Anhar Hassan; Keith A Josephs Journal: Mov Disord Clin Pract Date: 2019-05-29