The woman previously had undergone coronary artery bypass graft surgery and resection for colon carcinoma. She also had atrial fibrillation, hypertension, and diverticulosis, according to Dr. M. Yasir Haroon and Dr. Victor Jaramillo of Conemaugh Memorial Medical Center in Johnstown, Pa.
At the time of the incident, she had no associated headache, visual changes, dysarthria or dysphagia, tonic-clonic movements, incontinence, chest pain, palpitations, or shortness of breath.
In the emergency department, the patient was hemodynamically stable, awake, alert, and oriented. An electrocardiogram showed T-wave inversion in the lateral and inferior leads.
The woman was admitted for further evaluation of the syncopal episode and her left jaw pain. A previously performed x-ray of the mandible showed no bony abnormality. A chest x-ray performed at admission showed no acute pulmonary process.
Dr. Haroon and Dr. Jaramillo were consulted for possible trigeminal neuralgia, which may be initially experienced in short, mild attacks that may progress to longer, more frequent bouts of searing pain through the face. It is known to affect women more often than men as well as patients older than 50 years.
The neurologic exam was nonfocal. A brain MRI was performed, which showed a large, multilobular mass suggestive of meningioma in the prepontine region. The mass measured 3.6 cm craniocaudal by 3.2 cm transverse by 2.3 cm anterior-posterior, causing moderate mass effect.
An old infarction also was noted in the right basal ganglia, along with chronic white matter microvascular ischemic changes. An EEG showed slight abnormality with bilateral temporoparietal sharp wave discharges with epileptogenic potential.
A cardiac evaluation also was performed, revealing moderate stenosis of the right internal carotid artery and mild stenosis of the left internal carotid. A stress test was negative and an echocardiogram showed a left ventricular ejection fraction of 58% with no gross valvular abnormalities.
Dr. Haroon and Dr. Jaramillo concluded that the woman had trigeminal neuralgia and that her syncope episode was due to the large prepontine meningioma. Although the patient was referred for neurosurgery, she refused surgical treatment.
Posterior fossa tumors or meningiomas are rarely associated with syncope and trigeminal neuralgia in the literature. There have been very few case reports of trigeminal neuralgia caused by meningiomas located in the cerebellopontine angle and posterior fossa, Dr. Haroon noted. In this patient, the prepontine meningioma ipsilaterally compressed the trigeminal nerve. The doctors suggested that a posterior fossa tumor should be considered a potential cause of trigeminal neuralgia and syncope.
MRI shows a large lobular mass in the left prepontine region in coronal (left), T2 axial (middle), and T1 axial (right) views. PHOTOS COURTESY DR. M. YASIR HAROON
