Wing Beating Tremor and Double Panda Sign
Authors: Somasekharan Manoj MD, DM and K.V.S. Hari Kumar MD, DNB
Article first published online: 2 FEB 2015 | DOI: 10.1002/mdc3.12134
In March 2014, a 23-year-old man presented with insidious onset of gradually progressive tremors of the right hand of 1 year in duration. He noticed worsening of symptoms during the last 3 months with increased frequency of the tremors and inability to hold even small objects in the right hand. He denied symptoms pertaining to gait, memory, or speech functions and past history of jaundice. Similar complaints were not present in any family members, and there was no history of substance abuse. Physical examination revealed bilateral greenish brown rings in the cornea suggestive of Kayser-Fleischer rings (Fig. 1). Neurological examination revealed generalized hypertonia and “wing beating tremors” of the right arm (Fig. 1; Video 1). This tremor is classically observed in Wilson's disease (WD) and is posture induced as a result of the sustained abduction of the arms. MRI of the brain revealed the characteristic “face of the giant panda” sign in the midbrain and “face of the miniature panda” in the pons (Fig. 1).
Investigations revealed low serum levels of ceruloplasmin at 4 mg/dL (normal, 10–55) and elevated urinary copper excretion of 128 mg (normal, 10–20). His liver function tests and ultrasonography of the abdomen revealed no evidence of hepatic involvement. The diagnosis of WD was confirmed, and the patient was treated with zinc acetate 50 mg thrice-daily along with appropriate dietary advice. The characteristic neurological signs of WD are owing to the selective involvement of the brainstem nuclei with preservation of normal signal intensity in other areas, and the wing beating tremor is a result of the lesions in the dentatorubrothalamic pathway. At the 6-month follow-up visit, the tremor in the right hand had improved markedly, and the patient is able to hold a tea cup now.
Figure 1. A) Kayser-Fleischer ring over the cornea. (B) Wing beating tremor in the patient. (C) Face of the Giant Panda in the midbrain. (D) Face of the Miniature Panda in the pons. The authors confirm that patient consent was obtained for publication.