Procerus Sign in Corticobasal Degeneration.

Vertical wrinkling of the forehead or Procerus sign in Progressive Supranuclear Palsy

“…The absence of blepharospasm for diagnosis of this sign has been suggested by some Journal of the Neurological Sciences 298 (2010) 148-149 [4] but not others [1,3]. The presence of this vertical wrinkling on forehead has been suggested in one patient of suspected CBD [5] but not well documented. The common and overlapping features of PSP and CBD and existence of a variant of PSP with close resemblance to CBD (PSP-CBS) [11], may offer possible explanation to the existence of this sign in that particular case.…”

“…The sign has gained importance in literature and was quoted as a useful sign in subsequent texts [3,4]. One case has also been described with a clinical picture suggestive of Corticobasal degeneration with Procerus sign [5].…”

Procerus sign: Mechanism, clinical usefulness, and controversies

“…The procerus draws the medial angle of the eyebrows down, resulting in transverse wrinkling over the bridge of the nose. [ 2 3 4 ] Corrugator supercilii pulls the eyebrows downward and medially, leading to the vertical wrinkling of the supranasal skin of the forehead. [ 4 5 ] This anatomical principle is the basis of surgical resection and chemodenervation of corrugator supercilii to treat vertical glabellar creases.…”

“…[ 9 ] Although this sign was also described in probable corticobasal diseases, misdiagnosis of PSP Corticobasal degeneration clinically is common as both are characterized by selective 4-repeat Tau deposition. [ 2 8 10 ] One patient with probable multiple system atrophy (MSA) was also found to demonstrate this sign. [ 2 ] Hence, it is possible that widespread degeneration outside substantia nigra (as occurs in Parkinson's disease) is required to produce this sign.…”

“…[ 2 8 10 ] One patient with probable multiple system atrophy (MSA) was also found to demonstrate this sign. [ 2 ] Hence, it is possible that widespread degeneration outside substantia nigra (as occurs in Parkinson's disease) is required to produce this sign. However, recent literature suggests that PSP can present with predominantly cerebellar symptoms, making the distinction between probable MSA and atypical PSP clinically difficult.…”