Swallow tail sign is normally present in Substantia Nigra pars compacta due to the hyperintensity of nigrosome 1 containing cells on T2*/SWI sequences. Its absence is highly indicative of Parkinson’s disease.However, nigrostriatal dopaminergic degeneration is seen in progressive supranuclear palsy as well.It is important for neurologists and radiologists to assess the patient’s symptoms and signs to be able to provide the correct diagnosis,in view of further clinical management
Tewari, Siddharth and Prasad, Niharika
"Diagnostic dilemma: progressive supranuclear palsy with Parkinson’s disease,"
Manipal Journal of Medical Sciences: Vol. 7:
1, Article 2.
Available at: https://impressions.manipal.edu/mjms/vol7/iss1/2