UpToDate
Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate®

Progressive supranuclear palsy (PSP): Clinical features and diagnosis

Authors
Stewart A Factor, DO
Christine Doss Esper, MD
Section Editor
Howard I Hurtig, MD
Deputy Editor
John F Dashe, MD, PhD

INTRODUCTION

Symptoms and signs of Parkinsonism (ie, tremor, bradykinesia, rigidity, and postural instability) can be prominent in neurodegenerative disorders other than idiopathic Parkinson disease, particularly in atypical parkinsonian disorders, which include corticobasal degeneration, multiple system atrophy, and progressive supranuclear palsy.

Progressive supranuclear palsy (PSP), also known as Steele Richardson Olszewski syndrome, is an uncommon but not rare parkinsonian syndrome. Characteristic features of PSP and its variants include vertical supranuclear gaze palsy, postural instability with unexplained falls, akinesia, and cognitive dysfunction. This topic will review specifically the clinical features and diagnosis of PSP. Management and prognosis are reviewed elsewhere. (See "Progressive supranuclear palsy (PSP): Management and prognosis".)

Other neurodegenerative parkinsonian syndromes are discussed separately. (See "Clinical manifestations of Parkinson disease" and "Corticobasal degeneration" and "Multiple system atrophy: Clinical features and diagnosis" and "Diagnosis and differential diagnosis of Parkinson disease", section on 'Differential diagnosis'.)

HISTORICAL BACKGROUND

In 1964, Steele, Richardson, and Olszewski were the first to describe PSP when their seminal report of nine cases with neuropathology was published [1]. As a result of their pioneering work, some have referred to the disease as the Steele-Richardson-Olszewski syndrome. Since that time, hundreds of additional cases have been recorded, and the disease is now a well-recognized atypical parkinsonian syndrome (or Parkinson-plus disorder). As originally described, PSP was characterized by progressive supranuclear ophthalmoplegia, gait disorder and postural instability, dysarthria, dysphagia, rigidity, and frontal cognitive disturbance [1]. The consistent pathologic features of PSP consist of neuronal loss, globose neurofibrillary tangles, and gliosis mainly in the basal ganglia, cerebellum, brainstem, and to a lesser extent, the cerebral cortex [2]. A set of diagnostic criteria for PSP was initially proposed in 1996 [3], and revised in 2017 [4]. (See 'Diagnostic criteria' below.)

PSP is now recognized to encompass several phenotypic variants. The classical phenotype is now referred to as Richardson syndrome (PSP-RS), and other common variants include PSP with progressive gait freezing (PSP-PGF), PSP with predominant parkinsonism (PSP-P), and PSP with predominant frontal presentation (PSP-F).

                        

Subscribers log in here

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:
Literature review current through: Aug 2017. | This topic last updated: Aug 30, 2017.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
References
Top
  1. STEELE JC, RICHARDSON JC, OLSZEWSKI J. PROGRESSIVE SUPRANUCLEAR PALSY. A HETEROGENEOUS DEGENERATION INVOLVING THE BRAIN STEM, BASAL GANGLIA AND CEREBELLUM WITH VERTICAL GAZE AND PSEUDOBULBAR PALSY, NUCHAL DYSTONIA AND DEMENTIA. Arch Neurol 1964; 10:333.
  2. Golbe LI. Progressive Supranuclear Palsy. Curr Treat Options Neurol 2001; 3:473.
  3. Litvan I, Agid Y, Calne D, et al. Clinical research criteria for the diagnosis of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome): report of the NINDS-SPSP international workshop. Neurology 1996; 47:1.
  4. Höglinger GU, Respondek G, Stamelou M, et al. Clinical diagnosis of progressive supranuclear palsy: The movement disorder society criteria. Mov Disord 2017; 32:853.
  5. Bower JH, Maraganore DM, McDonnell SK, Rocca WA. Incidence of progressive supranuclear palsy and multiple system atrophy in Olmsted County, Minnesota, 1976 to 1990. Neurology 1997; 49:1284.
  6. Schrag A, Ben-Shlomo Y, Quinn NP. Prevalence of progressive supranuclear palsy and multiple system atrophy: a cross-sectional study. Lancet 1999; 354:1771.
  7. Respondek G, Kurz C, Arzberger T, et al. Which ante mortem clinical features predict progressive supranuclear palsy pathology? Mov Disord 2017; 32:995.
  8. Coyle-Gilchrist IT, Dick KM, Patterson K, et al. Prevalence, characteristics, and survival of frontotemporal lobar degeneration syndromes. Neurology 2016; 86:1736.
  9. Kawashima M, Miyake M, Kusumi M, et al. Prevalence of progressive supranuclear palsy in Yonago, Japan. Mov Disord 2004; 19:1239.
  10. Mastaglia FL, Grainger K, Kee F, et al. Progressive supranuclear palsy (the Steele-Richardson-Olszewski syndrome) clinical and electrophysiological observations in eleven cases. Proc Aust Assoc Neurol 1973; 10:35.
  11. Radhakrishnan K, Thacker AK, Maloo JC, et al. Descriptive epidemiology of some rare neurological diseases in Benghazi, Libya. Neuroepidemiology 1988; 7:159.
  12. Rajput AH, Offord KP, Beard CM, Kurland LT. Epidemiology of parkinsonism: incidence, classification, and mortality. Ann Neurol 1984; 16:278.
  13. Bower JH, Maraganore DM, McDonnell SK, Rocca WA. Incidence and distribution of parkinsonism in Olmsted County, Minnesota, 1976-1990. Neurology 1999; 52:1214.
  14. Wenning GK, Litvan I, Tolosa E. Milestones in atypical and secondary Parkinsonisms. Mov Disord 2011; 26:1083.
  15. Respondek G, Stamelou M, Kurz C, et al. The phenotypic spectrum of progressive supranuclear palsy: a retrospective multicenter study of 100 definite cases. Mov Disord 2014; 29:1758.
  16. Kristensen MO. Progressive supranuclear palsy--20 years later. Acta Neurol Scand 1985; 71:177.
  17. Golbe LI, Davis PH, Schoenberg BS, Duvoisin RC. Prevalence and natural history of progressive supranuclear palsy. Neurology 1988; 38:1031.
  18. Collins SJ, Ahlskog JE, Parisi JE, Maraganore DM. Progressive supranuclear palsy: neuropathologically based diagnostic clinical criteria. J Neurol Neurosurg Psychiatry 1995; 58:167.
  19. De Bruin VM, Lees AJ. Subcortical neurofibrillary degeneration presenting as Steele-Richardson-Olszewski and other related syndromes: a review of 90 pathologically verified cases. Mov Disord 1994; 9:381.
  20. Litvan I, Agid Y, Jankovic J, et al. Accuracy of clinical criteria for the diagnosis of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome). Neurology 1996; 46:922.
  21. Santacruz P, Uttl B, Litvan I, Grafman J. Progressive supranuclear palsy: a survey of the disease course. Neurology 1998; 50:1637.
  22. Maher ER, Lees AJ. The clinical features and natural history of the Steele-Richardson-Olszewski syndrome (progressive supranuclear palsy). Neurology 1986; 36:1005.
  23. Verny M, Duyckaerts C, Agid Y, Hauw JJ. The significance of cortical pathology in progressive supranuclear palsy. Clinico-pathological data in 10 cases. Brain 1996; 119 ( Pt 4):1123.
  24. Frasca J, Blumbergs PC, Henschke P, Burns RJ. A clinical and pathological study of progressive supranuclear palsy. Clin Exp Neurol 1991; 28:79.
  25. Baba Y, Putzke JD, Whaley NR, et al. Progressive supranuclear palsy: phenotypic sex differences in a clinical cohort. Mov Disord 2006; 21:689.
  26. Davis PH, Golbe LI, Duvoisin RC, Schoenberg BS. Risk factors for progressive supranuclear palsy. Neurology 1988; 38:1546.
  27. Golbe LI, Rubin RS, Cody RP, et al. Follow-up study of risk factors in progressive supranuclear palsy. Neurology 1996; 47:148.
  28. Caparros-Lefebvre D, Golbe LI, Deramecourt V, et al. A geographical cluster of progressive supranuclear palsy in northern France. Neurology 2015; 85:1293.
  29. McCrank E. PSP risk factors. Neurology 1990; 40:1637.
  30. McCrank E, Rabheru K. Four cases of progressive supranuclear palsy in patients exposed to organic solvents. Can J Psychiatry 1989; 34:934.
  31. Litvan I, Lees PS, Cunningham CR, et al. Environmental and occupational risk factors for progressive supranuclear palsy: Case-control study. Mov Disord 2016; 31:644.
  32. Kelley KD, Peavy G, Edland S, et al. The Role of Stress as a Risk Factor for Progressive Supranuclear Palsy. J Parkinsons Dis 2017; 7:377.
  33. de Yébenes JG, Sarasa JL, Daniel SE, Lees AJ. Familial progressive supranuclear palsy. Description of a pedigree and review of the literature. Brain 1995; 118 ( Pt 5):1095.
  34. Rojo A, Pernaute RS, Fontán A, et al. Clinical genetics of familial progressive supranuclear palsy. Brain 1999; 122 ( Pt 7):1233.
  35. Donker Kaat L, Boon AJ, Azmani A, et al. Familial aggregation of parkinsonism in progressive supranuclear palsy. Neurology 2009; 73:98.
  36. Im SY, Kim YE, Kim YJ. Genetics of Progressive Supranuclear Palsy. J Mov Disord 2015; 8:122.
  37. Höglinger GU, Melhem NM, Dickson DW, et al. Identification of common variants influencing risk of the tauopathy progressive supranuclear palsy. Nat Genet 2011; 43:699.
  38. Pittman AM, Myers AJ, Duckworth J, et al. The structure of the tau haplotype in controls and in progressive supranuclear palsy. Hum Mol Genet 2004; 13:1267.
  39. Rademakers R, Melquist S, Cruts M, et al. High-density SNP haplotyping suggests altered regulation of tau gene expression in progressive supranuclear palsy. Hum Mol Genet 2005; 14:3281.
  40. Pittman AM, Myers AJ, Abou-Sleiman P, et al. Linkage disequilibrium fine mapping and haplotype association analysis of the tau gene in progressive supranuclear palsy and corticobasal degeneration. J Med Genet 2005; 42:837.
  41. Zabetian CP, Hutter CM, Factor SA, et al. Association analysis of MAPT H1 haplotype and subhaplotypes in Parkinson's disease. Ann Neurol 2007; 62:137.
  42. Baker KB, Montgomery EB Jr. Performance on the PD test battery by relatives of patients with progressive supranuclear palsy. Neurology 2001; 56:25.
  43. Boeve BF. Progressive supranuclear palsy. Parkinsonism Relat Disord 2012; 18 Suppl 1:S192.
  44. Litvan I. Update on progressive supranuclear palsy. Curr Neurol Neurosci Rep 2004; 4:296.
  45. Litvan I, Mangone CA, McKee A, et al. Natural history of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome) and clinical predictors of survival: a clinicopathological study. J Neurol Neurosurg Psychiatry 1996; 60:615.
  46. Troost BT, Daroff RB. The ocular motor defects in progressive supranuclear palsy. Ann Neurol 1977; 2:397.
  47. Broderick M, Riley DE. Parkinson's-plus disorders. In: Parkinson's disease: Diagnosis and clinical management, 2nd ed, Factor SA, Weiner WJ (Eds), Demos Medical Publishing, New York 2008. p.727.
  48. Barclay CL, Lang AE. Dystonia in progressive supranuclear palsy. J Neurol Neurosurg Psychiatry 1997; 62:352.
  49. Rafal RD, Friedman JH. Limb dystonia in progressive supranuclear palsy. Neurology 1987; 37:1546.
  50. Dubois B, Pillon B, Legault F, et al. Slowing of cognitive processing in progressive supranuclear palsy. A comparison with Parkinson's disease. Arch Neurol 1988; 45:1194.
  51. Pillon B, Dubois B, Lhermitte F, Agid Y. Heterogeneity of cognitive impairment in progressive supranuclear palsy, Parkinson's disease, and Alzheimer's disease. Neurology 1986; 36:1179.
  52. Golbe LI, Boeve BF, Keegan BM, Parisi JE. An 81-year-old man with imbalance and memory impairment. Neurology 2007; 68:1147.
  53. Brown RG, Lacomblez L, Landwehrmeyer BG, et al. Cognitive impairment in patients with multiple system atrophy and progressive supranuclear palsy. Brain 2010; 133:2382.
  54. Pharr V, Uttl B, Stark M, et al. Comparison of apraxia in corticobasal degeneration and progressive supranuclear palsy. Neurology 2001; 56:957.
  55. Litvan I, Mega MS, Cummings JL, Fairbanks L. Neuropsychiatric aspects of progressive supranuclear palsy. Neurology 1996; 47:1184.
  56. Schrag A, Sheikh S, Quinn NP, et al. A comparison of depression, anxiety, and health status in patients with progressive supranuclear palsy and multiple system atrophy. Mov Disord 2010; 25:1077.
  57. Fukui T, Lee E, Hosoda H, Okita K. Obsessive-compulsive behavior as a symptom of dementia in progressive supranuclear palsy. Dement Geriatr Cogn Disord 2010; 30:179.
  58. Aldrich MS, Foster NL, White RF, et al. Sleep abnormalities in progressive supranuclear palsy. Ann Neurol 1989; 25:577.
  59. Walsh CM, Ruoff L, Varbel J, et al. Rest-activity rhythm disruption in progressive supranuclear palsy. Sleep Med 2016; 22:50.
  60. Boeve BF, Silber MH, Parisi JE, et al. Synucleinopathy pathology and REM sleep behavior disorder plus dementia or parkinsonism. Neurology 2003; 61:40.
  61. Williams DR, de Silva R, Paviour DC, et al. Characteristics of two distinct clinical phenotypes in pathologically proven progressive supranuclear palsy: Richardson's syndrome and PSP-parkinsonism. Brain 2005; 128:1247.
  62. Birdi S, Rajput AH, Fenton M, et al. Progressive supranuclear palsy diagnosis and confounding features: report on 16 autopsied cases. Mov Disord 2002; 17:1255.
  63. Williams DR, Lees AJ. What features improve the accuracy of the clinical diagnosis of progressive supranuclear palsy-parkinsonism (PSP-P)? Mov Disord 2010; 25:357.
  64. Boxer AL, Yu JT, Golbe LI, et al. Advances in progressive supranuclear palsy: new diagnostic criteria, biomarkers, and therapeutic approaches. Lancet Neurol 2017; 16:552.
  65. Kurz C, Ebersbach G, Respondek G, et al. An autopsy-confirmed case of progressive supranuclear palsy with predominant postural instability. Acta Neuropathol Commun 2016; 4:120.
  66. Williams DR, Holton JL, Strand K, et al. Pure akinesia with gait freezing: a third clinical phenotype of progressive supranuclear palsy. Mov Disord 2007; 22:2235.
  67. Facheris MF, Maniak S, Scaravilli F, et al. Pure akinesia as initial presentation of PSP: a clinicopathological study. Parkinsonism Relat Disord 2008; 14:517.
  68. Compta Y, Valldeoriola F, Tolosa E, et al. Long lasting pure freezing of gait preceding progressive supranuclear palsy: a clinicopathological study. Mov Disord 2007; 22:1954.
  69. Factor SA, Higgins DS, Qian J. Primary progressive freezing gait: a syndrome with many causes. Neurology 2006; 66:411.
  70. Factor SA, Jennings DL, Molho ES, Marek KL. The natural history of the syndrome of primary progressive freezing gait. Arch Neurol 2002; 59:1778.
  71. Donker Kaat L, Boon AJ, Kamphorst W, et al. Frontal presentation in progressive supranuclear palsy. Neurology 2007; 69:723.
  72. Han HJ, Kim H, Park JH, et al. Behavioral changes as the earliest clinical manifestation of progressive supranuclear palsy. J Clin Neurol 2010; 6:148.
  73. Hassan A, Parisi JE, Josephs KA. Autopsy-proven progressive supranuclear palsy presenting as behavioral variant frontotemporal dementia. Neurocase 2012; 18:478.
  74. Boeve B, Dickson D, Duffy J, et al. Progressive nonfluent aphasia and subsequent aphasic dementia associated with atypical progressive supranuclear palsy pathology. Eur Neurol 2003; 49:72.
  75. Josephs KA, Duffy JR. Apraxia of speech and nonfluent aphasia: a new clinical marker for corticobasal degeneration and progressive supranuclear palsy. Curr Opin Neurol 2008; 21:688.
  76. Santos-Santos MA, Mandelli ML, Binney RJ, et al. Features of Patients With Nonfluent/Agrammatic Primary Progressive Aphasia With Underlying Progressive Supranuclear Palsy Pathology or Corticobasal Degeneration. JAMA Neurol 2016; 73:733.
  77. Mochizuki A, Ueda Y, Komatsuzaki Y, et al. Progressive supranuclear palsy presenting with primary progressive aphasia--clinicopathological report of an autopsy case. Acta Neuropathol 2003; 105:610.
  78. Josephs KA, Duffy JR, Strand EA, et al. Clinicopathological and imaging correlates of progressive aphasia and apraxia of speech. Brain 2006; 129:1385.
  79. Cordato NJ, Halliday GM, McCann H, et al. Corticobasal syndrome with tau pathology. Mov Disord 2001; 16:656.
  80. Boeve BF, Maraganore DM, Parisi JE, et al. Pathologic heterogeneity in clinically diagnosed corticobasal degeneration. Neurology 1999; 53:795.
  81. Tsuboi Y, Josephs KA, Boeve BF, et al. Increased tau burden in the cortices of progressive supranuclear palsy presenting with corticobasal syndrome. Mov Disord 2005; 20:982.
  82. Josephs KA, Petersen RC, Knopman DS, et al. Clinicopathologic analysis of frontotemporal and corticobasal degenerations and PSP. Neurology 2006; 66:41.
  83. Ling H, O'Sullivan SS, Holton JL, et al. Does corticobasal degeneration exist? A clinicopathological re-evaluation. Brain 2010; 133:2045.
  84. Ling H, de Silva R, Massey LA, et al. Characteristics of progressive supranuclear palsy presenting with corticobasal syndrome: a cortical variant. Neuropathol Appl Neurobiol 2014; 40:149.
  85. Kanazawa M, Shimohata T, Toyoshima Y, et al. Cerebellar involvement in progressive supranuclear palsy: A clinicopathological study. Mov Disord 2009; 24:1312.
  86. Iwasaki Y, Mori K, Ito M, et al. An autopsied case of progressive supranuclear palsy presenting with cerebellar ataxia and severe cerebellar involvement. Neuropathology 2013; 33:561.
  87. Kanazawa M, Tada M, Onodera O, et al. Early clinical features of patients with progressive supranuclear palsy with predominant cerebellar ataxia. Parkinsonism Relat Disord 2013; 19:1149.
  88. Koga S, Josephs KA, Ogaki K, et al. Cerebellar ataxia in progressive supranuclear palsy: An autopsy study of PSP-C. Mov Disord 2016; 31:653.
  89. Shimohata T, Kanazawa M, Yoshida M, et al. Clinical and imaging findings of progressive supranuclear palsy with predominant cerebellar ataxia. Mov Disord 2016; 31:760.
  90. Josephs KA, Katsuse O, Beccano-Kelly DA, et al. Atypical progressive supranuclear palsy with corticospinal tract degeneration. J Neuropathol Exp Neurol 2006; 65:396.
  91. Nagao S, Yokota O, Nanba R, et al. Progressive supranuclear palsy presenting as primary lateral sclerosis but lacking parkinsonism, gaze palsy, aphasia, or dementia. J Neurol Sci 2012; 323:147.
  92. Graber JJ, Staudinger R. Teaching NeuroImages: "Penguin" or "hummingbird" sign and midbrain atrophy in progressive supranuclear palsy. Neurology 2009; 72:e81.
  93. Kato N, Arai K, Hattori T. Study of the rostral midbrain atrophy in progressive supranuclear palsy. J Neurol Sci 2003; 210:57.
  94. Shukla R, Sinha M, Kumar R, Singh D. 'Hummingbird' sign in progressive supranuclear palsy. Ann Indian Acad Neurol 2009; 12:133.
  95. Tsuboi Y, Slowinski J, Josephs KA, et al. Atrophy of superior cerebellar peduncle in progressive supranuclear palsy. Neurology 2003; 60:1766.
  96. Hauw JJ, Daniel SE, Dickson D, et al. Preliminary NINDS neuropathologic criteria for Steele-Richardson-Olszewski syndrome (progressive supranuclear palsy). Neurology 1994; 44:2015.
  97. Scaravilli T, Pramstaller PP, Salerno A, et al. Neuronal loss in Onuf's nucleus in three patients with progressive supranuclear palsy. Ann Neurol 2000; 48:97.
  98. Takahashi M, Weidenheim KM, Dickson DW, Ksiezak-Reding H. Morphological and biochemical correlations of abnormal tau filaments in progressive supranuclear palsy. J Neuropathol Exp Neurol 2002; 61:33.
  99. Feany MB, Dickson DW. Neurodegenerative disorders with extensive tau pathology: a comparative study and review. Ann Neurol 1996; 40:139.
  100. Gearing M, Olson DA, Watts RL, Mirra SS. Progressive supranuclear palsy: neuropathologic and clinical heterogeneity. Neurology 1994; 44:1015.
  101. Scaravilli T, Tolosa E, Ferrer I. Progressive supranuclear palsy and corticobasal degeneration: lumping versus splitting. Mov Disord 2005; 20 Suppl 12:S21.
  102. Houlden H, Baker M, Morris HR, et al. Corticobasal degeneration and progressive supranuclear palsy share a common tau haplotype. Neurology 2001; 56:1702.
  103. Higgins JJ, Golbe LI, De Biase A, et al. An extended 5'-tau susceptibility haplotype in progressive supranuclear palsy. Neurology 2000; 55:1364.
  104. Kasashima S, Oda Y. Cholinergic neuronal loss in the basal forebrain and mesopontine tegmentum of progressive supranuclear palsy and corticobasal degeneration. Acta Neuropathol 2003; 105:117.
  105. Warren NM, Piggott MA, Lees AJ, Burn DJ. The basal ganglia cholinergic neurochemistry of progressive supranuclear palsy and other neurodegenerative diseases. J Neurol Neurosurg Psychiatry 2007; 78:571.
  106. Pascual J, Berciano J, Grijalba B, et al. Dopamine D1 and D2 receptors in progressive supranuclear palsy: an autoradiographic study. Ann Neurol 1992; 32:703.
  107. Pierot L, Desnos C, Blin J, et al. D1 and D2-type dopamine receptors in patients with Parkinson's disease and progressive supranuclear palsy. J Neurol Sci 1988; 86:291.
  108. Juncos JL, Hirsch EC, Malessa S, et al. Mesencephalic cholinergic nuclei in progressive supranuclear palsy. Neurology 1991; 41:25.
  109. Zweig RM, Whitehouse PJ, Casanova MF, et al. Loss of pedunculopontine neurons in progressive supranuclear palsy. Ann Neurol 1987; 22:18.
  110. Suzuki M, Desmond TJ, Albin RL, Frey KA. Cholinergic vesicular transporters in progressive supranuclear palsy. Neurology 2002; 58:1013.
  111. Holemans S, Javoy F, Agid Y, et al. [3H]MK-801 binding to NMDA glutamatergic receptors in Parkinson's disease and progressive supranuclear palsy. Brain Res 1991; 565:154.
  112. Levy R, Ruberg M, Herrero MT, et al. Alterations of GABAergic neurons in the basal ganglia of patients with progressive supranuclear palsy: an in situ hybridization study of GAD67 messenger RNA. Neurology 1995; 45:127.
  113. Williams DR, Lees AJ. Progressive supranuclear palsy: clinicopathological concepts and diagnostic challenges. Lancet Neurol 2009; 8:270.
  114. Mendell JR, Engel WK, Chase TN. Modification by L-dopa of a case of progressive supranuclear palsy. With evidence of defective cerebral dopamine metabolism. Lancet 1970; 1:593.
  115. Urakami K, Wada K, Arai H, et al. Diagnostic significance of tau protein in cerebrospinal fluid from patients with corticobasal degeneration or progressive supranuclear palsy. J Neurol Sci 2001; 183:95.
  116. Borroni B, Malinverno M, Gardoni F, et al. Tau forms in CSF as a reliable biomarker for progressive supranuclear palsy. Neurology 2008; 71:1796.
  117. Warmuth-Metz M, Naumann M, Csoti I, Solymosi L. Measurement of the midbrain diameter on routine magnetic resonance imaging: a simple and accurate method of differentiating between Parkinson disease and progressive supranuclear palsy. Arch Neurol 2001; 58:1076.
  118. Oba H, Yagishita A, Terada H, et al. New and reliable MRI diagnosis for progressive supranuclear palsy. Neurology 2005; 64:2050.
  119. Looi JC, Macfarlane MD, Walterfang M, et al. Morphometric analysis of subcortical structures in progressive supranuclear palsy: In vivo evidence of neostriatal and mesencephalic atrophy. Psychiatry Res 2011; 194:163.
  120. Quattrone A, Nicoletti G, Messina D, et al. MR imaging index for differentiation of progressive supranuclear palsy from Parkinson disease and the Parkinson variant of multiple system atrophy. Radiology 2008; 246:214.
  121. Morelli M, Arabia G, Salsone M, et al. Accuracy of magnetic resonance parkinsonism index for differentiation of progressive supranuclear palsy from probable or possible Parkinson disease. Mov Disord 2011; 26:527.
  122. Morelli M, Arabia G, Novellino F, et al. MRI measurements predict PSP in unclassifiable parkinsonisms: a cohort study. Neurology 2011; 77:1042.
  123. Massey LA, Jäger HR, Paviour DC, et al. The midbrain to pons ratio: a simple and specific MRI sign of progressive supranuclear palsy. Neurology 2013; 80:1856.
  124. Mishina M, Ishii K, Mitani K, et al. Midbrain hypometabolism as early diagnostic sign for progressive supranuclear palsy. Acta Neurol Scand 2004; 110:128.
  125. Blin J, Baron JC, Dubois B, et al. Positron emission tomography study in progressive supranuclear palsy. Brain hypometabolic pattern and clinicometabolic correlations. Arch Neurol 1990; 47:747.
  126. Foster NL, Gilman S, Berent S, et al. Cerebral hypometabolism in progressive supranuclear palsy studied with positron emission tomography. Ann Neurol 1988; 24:399.
  127. Goffinet AM, De Volder AG, Gillain C, et al. Positron tomography demonstrates frontal lobe hypometabolism in progressive supranuclear palsy. Ann Neurol 1989; 25:131.
  128. Brooks DJ, Ibanez V, Sawle GV, et al. Striatal D2 receptor status in patients with Parkinson's disease, striatonigral degeneration, and progressive supranuclear palsy, measured with 11C-raclopride and positron emission tomography. Ann Neurol 1992; 31:184.
  129. Gardner RC, Boxer AL, Trujillo A, et al. Intrinsic connectivity network disruption in progressive supranuclear palsy. Ann Neurol 2013; 73:603.
  130. Rivaud-Péchoux S, Vidailhet M, Gallouedec G, et al. Longitudinal ocular motor study in corticobasal degeneration and progressive supranuclear palsy. Neurology 2000; 54:1029.
  131. Murphy MA, Friedman JH, Tetrud JW, Factor SA. Neurodegenerative disorders mimicking progressive supranuclear palsy: a report of three cases. J Clin Neurosci 2005; 12:941.
  132. Dubinsky RM, Jankovic J. Progressive supranuclear palsy and a multi-infarct state. Neurology 1987; 37:570.
  133. Weiner WJ. A differential diagnosis of Parkinsonism. Rev Neurol Dis 2005; 2:124.
  134. Fernández-Fournier M, Perry DC, Tartaglia MC, et al. Precipitous Deterioration of Motor Function, Cognition, and Behavior. JAMA Neurol 2017; 74:591.
  135. David NJ, Mackey EA, Smith JL. Further observations in progressive supranuclear palsy. Neurology 1968; 18:349.