Figure 4 (postoperative MRI T2 sagital view)
Discussion:
The first description of Harlequin syndrome was in 1988 by Lance at al.1They described five cases of adult patients with unilateral flushing and sweating with contralateral anhidrosis. In years that followed (1993) this phenomenon was described as a dysfunction of the pregangliotic and postganglioticcervical sympathetic nerve fibers and parasympathetic neurons of ciliary ganglion5.
The anatomy of sympathetic fibers innervating the face are made of a three- neuron chain pathway: first neurons originate in hypothalamus and synapse in the intermediolateral cell column of the upper thoracic spinal cord with preganglionic fibers (second neurons) - somewhere between Th1 – Th3 9. Preganglionic fibers leave the spinal cord at Th2 -Th3, synapsing with the postganglionic fibers (third neurons) in superior cervical ganglion. Then, postganglionic fibers leave cervical ganglion passing either along internal carotid artery to supply forehead, nose and eye, or along external carotid artery to supply the rest of the face. Preganglionic oculosympathetic neurons originate at the level of Th1.
In our case the lesion is at the level of inferior cervical ganglion (stellate ganglion) given the symptoms – unilateral facial flushing and upper extremity and trunk, without Horner’s syndrome. Harlequin sign in our case presented probably due to resection of sympathetic nerves while removing meningioma.
The PubMed database was searched online (PubMed, http:// pubmed.com). A search query using Harlequin syndrome revealed 129 published cases of which 23 was iatrogenic. (Table 1) Of 23 patients female sex was predominant -15:8 ratio in which 8 were pediatric patients.
Most of the patients had undergone a thoracic surgery (8 patients), Intrathecal pump in 3 patients, total thyroidectomy and neck surgery (3 patients), five patients underwent spinal nerve block, and only two had neurosurgical procedure.
Conclusion:
Harlequin syndrome as a condition often frightens the patients since it happens after the operation, while they perform their usual activities. In most cases (about 80%) it resolves by itself within few hours. The patient fear and anxiety can be calmed by explaining the benign nature of the condition. If the patient has long term sequelae and the symptoms aren’t tolerable, a contralateral sympathectomy or stellate ganglion block are options for symptom relief32,33.