A 16-year-old female presented to the Emergency Department with a tongue laceration. She was playfighting with her brother who swung a samurai sword and cut her tongue as she tried to dodge it. She denied headaches, constitutional symptoms, weakness, or loss of consciousness. The history was otherwise unremarkable. She was alert with normal vital signs. Her tongue was swollen with a 1-cm laceration. She was admitted due to inability to tolerate oral intake.
During admission, the patient reported having difficulty opening her right eye. On exam, she was found to have anisocoria but it was unclear whether this finding was new (Figure 1). With no other symptoms, her difficulty with right eye opening was presumed to be from direct trauma and the patient was discharged home.
Figure 1.
Photos of patient after injury. Pupils were assessed (A) acutely postinjury, (B) 6 weeks postinjury and (C) 5 months postinjury in dim lighting showing ptosis and anisocoria without significant improvement over time.
She returned days later with persistent symptoms. On examination, she was found to have right-sided ptosis and anisocoria. Pupils were 3 mm on the right and 5 mm on the left in bright illumination, with the right pupil dilating poorly and slowly in dim illumination. Her right neck was tender with no cervical spine tenderness. Carotid pulses were symmetric with no bruits. The remainder of the examination was unremarkable. Urgent imaging assisted in the diagnosis.
DISCUSSION
A diagnosis of acute acquired right-sided Horner syndrome was made based on the history and physical exam findings. Computed tomography angiogram (CTA) of the head and neck revealed normal neck vasculature with no carotid artery dissection, but a small amount of air was seen in the right parapharyngeal space, with antero-lateral compression of the right side of the oropharynx. Subsequent magnetic resonance imaging (MRI) revealed an area of abnormal enhancement in the right lateral parapharyngeal area partially encasing the right internal and external carotid vessels (Figure 2). The findings were most in keeping with a right jugular vein hematoma with secondary compression of the right sympathetic chain, resulting from the patient’s neck hyperextension during her attempt to avoid the sword.
Figure 2.
Imaging findings of 16-year-old female with Horner syndrome. (A) Axial Computed Tomography image. Free air (arrow in A) in the right parapharyngeal space, surrounded by an area that was iso-attenuated to muscle and resulted in antero-lateral compression of the right side of the oropharynx (*). (B) Magnetic resonance imaging (MRI) Axial T1. (C) MRI Axial T2 with fat suppression. MRI demonstrated abnormal signal in the oropharyngeal region involving the right lateral parapharyngeal space (arrow in C), posterior to the tongue. It extended from the level of the cranio-cervical junction to C4 level and along the antero-medial aspect of the carotid sheath, partially encasing both the internal and the external carotid arteries.
Horner syndrome (unilateral miosis, ptosis, and anhidrosis) results from disruptions along the oculosympathetic pathway. Congenital causes include birth-related trauma and infections while acquired causes include malignancies (neuroblastoma, Pancoast tumors, rhabdomyosarcoma), brainstem vascular malformations or tumors, carotid artery thrombosis or dissection, and direct blunt or penetrating neck trauma. Paediatric Horner syndrome is rare with an estimated incidence of 1.42 per 100,000. To our knowledge, this is the first case of acquired Horner syndrome from a neck hyperextension injury in a paediatric patient due to jugular vein hematoma.
A detailed history should be obtained in any patient with anisocoria and ptosis including symptom onset, birth and surgical history, and recent trauma to the cervical area. As physiologic anisocoria is found in 19% of the general population, asking patients for photos of themselves prior to an incident can help differentiate pathological and physiological anisocoria. Anhidrosis is only present in central or preganglionic lesions (brainstem, cervicothoracic spinal cord, thoracic outlet, or lung apex) due to the anatomic location of the sympathetic fibers responsible for facial sweating. Expectedly, anhidrosis was not a symptom in this case.
The history should be followed by a thorough physical exam, including a full neurologic examination with pupillary assessment. When localizing the abnormal pupil, an abnormally constricted pupil will have greater anisocoria in darkness (as in Horner syndrome), while an abnormally dilated pupil will have greater anisocoria in light. Dilation lag, the delay in pupil dilation after an abrupt dimming of room illumination, is variably present in Horner syndrome and typically takes time to develop, but has 100% specificity and 53% sensitivity (1). Dilation lag was noted in our patient which helped confirm the diagnosis.
A patient with acute Horner syndrome and neck pain should be presumed to have carotid dissection until proven otherwise and emergent imaging should be obtained. CTA and MRI should be used in a complementary fashion to localize the lesion in Horner syndrome, as was done in our case. CTA provides rapid assessment to exclude vascular injury while MRI is helpful for soft tissue details. MRI in our case delineated the presence of a parapharyngeal hematoma from hyperextension injury to the neck vessels. Expansion of this hematoma presumably caused irritation and compression of the cervical sympathetic chain which runs alongside the internal jugular vein and carotid artery within the carotid sheath.
Post-traumatic Horner syndrome may resolve within days to months but in some cases fails to improve (2). In this case, while topical apraclonidine provided partial and temporary relief of ptosis, the patient’s symptoms persisted over several months, necessitating surgical resection of the right Muëller muscle to mechanically elevate the eyelid. The anisocoria did not improve.
CLINICAL PEARLS
Traumatic Horner syndrome should be considered when ptosis and miosis are present after neck hyperextension, even in the absence of blunt or penetrating neck trauma. Traumatic Horner syndrome is especially important to recognize due to the risk of injury to vascular structures adjacent to the sympathetic fibres, in particular the carotid artery.
As physiologic anisocoria is found in 19% of the general population, asking patients for photos of themselves prior to an incident can help differentiate between physiologic or pathologic anisocoria such as due to Horner syndrome.
A thorough history and physical exam are crucial to the diagnosis of Horner syndrome, with dilation lag being especially specific to the diagnosis. Imaging is critical to identify a cause of Horner Syndrome.
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Funding: There are no funders to report for this submission.
Potential Conflicts of Interest: All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
References
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