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Pontine Hemorrhage Presenting as an Isolated Facial Nerve Palsy
NEUROLOGY/CASE REPORT
Pontine Hemorrhage Presenting as an Isolated Facial Nerve Palsy Scott C. Sherman, MD Trevonne T. Thompson, MD
From the Cook County Hospital, Department of Emergency Medicine, Chicago, IL.
We report a case of an isolated facial nerve palsy in a young, otherwise healthy man who was found to have a pontine hemorrhage on computed tomography. Pontine hemorrhage is a rare cause of facial nerve palsy and has been reported in the literature as an isolated neurologic finding in only 1 other instance. This case reminds the emergency physician to remain vigilant for alternative causes of facial nerve palsy other than ‘‘idiopathic’’ Bell’s palsy. [Ann Emerg Med. 2005;46:64-66.]
0196-0644/$-see front matter Copyright ª 2005 by the American College of Emergency Physicians. doi:10.1016/j.annemergmed.2004.12.008
INTRODUCTION Facial nerve palsy is commonly encountered by emergency physicians. Although the majority of cases are found to be idiopathic Bell’s palsy, recognizing other causes for this lesion is essential.1 We present a case of a young patient who presented with features consistent with an isolated facial nerve palsy and was found to have a pontine hemorrhage on computed tomography (CT). This type of lesion has not been reported in the emergency medicine literature previously.
CASE REPORT A 37-year-old man presented to the emergency department (ED) with a chief complaint of difficulty using the right side of his face. He stated that the symptoms had been present since he awoke 2 days before. He denied headaches or vomiting. He had no visual complaints or diplopia. There was no history of change in lacrimation, salivation, taste, or hearing. He denied taking any other medications. He had no other relevant medical history. He had no allergies and used alcohol occasionally. Physical examination revealed a young healthy man in no acute distress. Vital signs were blood pressure 132/82 mm Hg, pulse rate 84 beats/min, respiratory rate 20 breaths/min, and temperature 37.0 C (98.5 F). His extraocular movements were intact, and there was no nystagmus. There was no papilledema, and pupils were equal and reactive. Sensation to the face was normal. The patient was unable to raise the right side of his mouth or wrinkle his forehead on the right (Figure 1A, B). Hearing was grossly intact, and the tympanic membranes and external auditory canal did not reveal any vesicles. The tongue was midline. The results of the remainder of his cranial nerve examination were normal. Motor and sensory examinations were intact in the upper and lower extremities. Reflexes were equal, and the gait was normal. No other abnormalities were noted on the remainder of the examination. 64 Annals of Emergency Medicine
Additional medical history was obtained from the patient, who stated that he had been at an outside hospital the preceding day, where a CT scan of the head was performed and revealed the presence of ‘‘bleeding in the brain.’’ The patient signed out against medical advice because he was afraid he could not pay for hospitalization. No further information was available from this visit; however, the patient stated that he felt no different at that time. A repeated CT scan revealed the presence of a right pontine hemorrhage anterior to the fourth ventricle on the right (Figure 2). The neurosurgery service was consulted, and the patient had a magnetic resonance imaging (MRI) scan of the brain that revealed the source of the hemorrhage to be a cavernous angioma. Because of the location within the brainstem, the decision was made to treat the patient conservatively, and at 6-month follow-up the patient was doing well, with some improvement in his right seventh nerve palsy.
DISCUSSION Seventh cranial nerve palsy is a common diagnosis made in the ED setting. Its idiopathic form, Bell’s palsy, accounts for approximately 50% to 75% of cases. The diagnosis is usually clinical. The typical presentation includes the acute onset (within 1 week) of unilateral paresis of the muscles of facial expression and numbness or heaviness of the affected side without demonstrable sensory deficit. Loss of lacrimation is present in 67% of patients, whereas taste disorders are elicited in 34% of patients. In approximately 50% of patients, pain is present behind the ear. Ipsilateral hyperacusis is found in 14% of cases.1-3 The evaluation of a patient with a seventh cranial nerve palsy generally consists of a thorough medical history and physical examination looking for an identifiable etiology. Laboratory or radiographic studies are considered unnecessary when the presentation is typical. Atypical features include slow onset, Volume 46, no. 1 : July 2005
Sherman & Thompson
Pontine Hemorrhage
Figure 1. Patient demonstrating right seventh cranial nerve palsy when asked to A, show his teeth and B, raise his eyebrows.
otorrhea, vestibular complaints, recent trauma, hearing loss or tinnitus, and other focal neurologic findings.3 Atypical features justify further evaluation, including imaging modalities. When atypical features are present or questions are raised by the medical history or physical examination, other etiologies must be considered. In a study of more than 2,500 patients with a seventh cranial nerve palsy, a total of 37 etiologies were identified, the most common being neonatal, herpes zoster (Ramsey Hunt syndrome), trauma, and diabetes mellitus. Other etiologies commonly cited include Lyme disease, herpes simplex, tumors, multiple sclerosis, sarcoidosis, AIDS, and vascular pontine lesions. Vascular pontine lesions are a rare cause of a seventh nerve palsy, present in only 1% of cases.1 Even more unlikely is a pontine lesion that precipitates an isolated seventh nerve deficit. The seventh cranial nerve lies in close proximity to multiple other important nervous structures within the pons (Figure 3). Commonly injured adjacent structures include the abducens nerve,4 the trigeminal nerve,5 and the vestibular nerve.6 If the medial longitudinal fasciculus is affected, an intranuclear ophthalmoplegia is present in which adduction is impaired on the affected side. A lesion affecting the closely approximated structures of the medial longitudinal Volume 46, no. 1 : July 2005
fasciculus, abducens nerve, and the paramedian pontine reticular formation is known as one-and-a-half syndrome. In this syndrome, the only preserved horizontal eye movement is abduction on the unaffected side. If the seventh cranial nerve is affected additionally, it is termed eight-and-a-half syndrome.7 The case presented here illustrates a deviation from the typical presentation and pathology. Our patient did not have atypical features, nor did he have anything in his history or physical examination that suggested an alternative etiology. A CT scan would not have been ordered by these authors had the patient not given the additional history that an abnormal CT scan of the brain was obtained the preceding day. It is unclear what prompted imaging on the initial visit. It was interesting to note that our patient lacked some of the frequently present symptoms of idiopathic seventh nerve palsy in that he had intact lacrimation and taste, which can be explained by the location of the lesion. The parasympathetic (lacrimation and salivation) and special sensory components (taste) of the seventh cranial nerve are transmitted to the superior salivatory nucleus and nucleus solitarius, respectively. These nuclei, as shown in Figure 3, were in proximity to the lesion in this case but did not affect them. Annals of Emergency Medicine 65
Sherman & Thompson
Pontine Hemorrhage
seventh nerve palsies caused by pontine infarctions. Only 50% of these lesions were identified on MRI, and the remainder were detected by electrophysiologic testing that indicated pontine dysfunction.8 An additional report occurred in a patient with multiple sclerosis.9 One report described an elderly hypertensive man with a pontine hemorrhage noted on MRI in a location similar to that of our patient.10 In conclusion, this case, although rare, is important because it reminds the emergency physician to consider all diagnostic possibilities when evaluating a patient with a seventh cranial nerve palsy. Despite the etiology of the cranial nerve deficit in this case, it would be difficult to recommend routine imaging in cases of isolated seventh nerve palsies. The number of additional imaging studies performed does not seem justified by the rarity of this condition, especially in a young patient with an otherwise typical onset. Supervising editor: William G. Barsan, MD Funding and support: The authors report this study did not receive any outside funding or support. Publication dates: Received for publication November 15, 2004. Revision received December 7, 2004. Accepted for publication December 8, 2004. Available online April 13, 2005. Reprints not available from the authors. Figure 2. CT scan demonstrating a pontine hemorrhage in the right pons just anterior to the fourth ventricle and in the vicinity of the facial nerve nuclei.
Address for correspondence: Scott C. Sherman, MD, Department of Emergency Medicine, Cook County Hospital, 1900 W Polk Avenue, 10th Floor, Chicago, IL 60612; 312-864-0199, fax 312-864-9656; E-mail [email protected]. REFERENCES
Figure 3. Schematic representation of the caudal pons showing the close proximity of nervous structures. CN, Cranial nerve; MLF, medial longitudinal fasciculus; NS, nucleus solitarius; SSN, superior salivatory nucleus; PPRF, paramedian pontine reticular formation. Adapted from Spector and Stark. Arch Neurol. 1983.11
There have been previous reports of cases of isolated seventh nerve palsies caused by pontine lesions. One study of diabetic and hypertensive patients identified 10 patients with isolated 66 Annals of Emergency Medicine
1. Peitersen E. Bell’s palsy: the spontaneous course of 2,500 peripheral facial nerve palsies of different etiologies. Acta Otolaryngol Suppl. 2002;549:4-30. 2. Perry JR, Hasso AN. Magnetic resonance imaging of cranial nerve VII. Top Magn Reson Imaging. 1996;8:155-163. 3. Roob G, Fazekas F, Hartung HP. Peripheral facial palsy: etiology, diagnosis and treatment. Eur Neurol. 1999;41:3-9. 4. Roh JK, Kim BK, Chung JM. Combined peripheral facial and abducens nerve palsy caused by caudal tegmental pontine infarction. Eur Neurol. 1999;41:99-102. 5. Waterman G, Epstein JD, Fenske NA. Herpes zoster infection with trigeminal and facial nerve involvement. Cutis. 1989;43: 262-263. 6. Biavati MJ, Gross JD, Wilson WR, et al. Magnetic resonance imaging evidence of a focal pontine ischemia in sudden hearing loss and seventh nerve paralysis. Am J Otol. 1994;15:250-253. 7. Eggenberger E. Eight-and-a-half syndrome: one-and-a-half syndrome plus cranial nerve VII palsy. J Neuroophthalmol. 1998;18:114-116. 8. Thomke F, Urban PP, Marx JJ, et al. Seventh nerve palsies may be the only clinical sign of small pontine infarctions in diabetic and hypertensive patients. J Neurol. 2002;249:1556-1562. 9. Schnorpfeil F, Braune HJ. Nuclear facial palsy in multiple sclerosis: a case report. Electromyogr Clin Neurophysiol. 1997;37:207-211. 10. Martinez-Garcia FA, Salmeron P, Morales-Ortiz A, et al. [Pontine hemorrhage as a cause of peripheral facial paralysis]. Rev Neurol. 1996;24:984-986. 11. Spector RH, Stark S. Peripheral facial palsy with intact taste and tearing caused by intrapontine lesion. Arch Neurol. 1983; 40:317-319.
Volume 46, no. 1 : July 2005
Pontine Hemorrhage Presenting as an Isolated Facial Nerve Palsy Scott C. Sherman, MD Trevonne T. Thompson, MD
From the Cook County Hospital, Department of Emergency Medicine, Chicago, IL.
We report a case of an isolated facial nerve palsy in a young, otherwise healthy man who was found to have a pontine hemorrhage on computed tomography. Pontine hemorrhage is a rare cause of facial nerve palsy and has been reported in the literature as an isolated neurologic finding in only 1 other instance. This case reminds the emergency physician to remain vigilant for alternative causes of facial nerve palsy other than ‘‘idiopathic’’ Bell’s palsy. [Ann Emerg Med. 2005;46:64-66.]
0196-0644/$-see front matter Copyright ª 2005 by the American College of Emergency Physicians. doi:10.1016/j.annemergmed.2004.12.008
INTRODUCTION Facial nerve palsy is commonly encountered by emergency physicians. Although the majority of cases are found to be idiopathic Bell’s palsy, recognizing other causes for this lesion is essential.1 We present a case of a young patient who presented with features consistent with an isolated facial nerve palsy and was found to have a pontine hemorrhage on computed tomography (CT). This type of lesion has not been reported in the emergency medicine literature previously.
CASE REPORT A 37-year-old man presented to the emergency department (ED) with a chief complaint of difficulty using the right side of his face. He stated that the symptoms had been present since he awoke 2 days before. He denied headaches or vomiting. He had no visual complaints or diplopia. There was no history of change in lacrimation, salivation, taste, or hearing. He denied taking any other medications. He had no other relevant medical history. He had no allergies and used alcohol occasionally. Physical examination revealed a young healthy man in no acute distress. Vital signs were blood pressure 132/82 mm Hg, pulse rate 84 beats/min, respiratory rate 20 breaths/min, and temperature 37.0 C (98.5 F). His extraocular movements were intact, and there was no nystagmus. There was no papilledema, and pupils were equal and reactive. Sensation to the face was normal. The patient was unable to raise the right side of his mouth or wrinkle his forehead on the right (Figure 1A, B). Hearing was grossly intact, and the tympanic membranes and external auditory canal did not reveal any vesicles. The tongue was midline. The results of the remainder of his cranial nerve examination were normal. Motor and sensory examinations were intact in the upper and lower extremities. Reflexes were equal, and the gait was normal. No other abnormalities were noted on the remainder of the examination. 64 Annals of Emergency Medicine
Additional medical history was obtained from the patient, who stated that he had been at an outside hospital the preceding day, where a CT scan of the head was performed and revealed the presence of ‘‘bleeding in the brain.’’ The patient signed out against medical advice because he was afraid he could not pay for hospitalization. No further information was available from this visit; however, the patient stated that he felt no different at that time. A repeated CT scan revealed the presence of a right pontine hemorrhage anterior to the fourth ventricle on the right (Figure 2). The neurosurgery service was consulted, and the patient had a magnetic resonance imaging (MRI) scan of the brain that revealed the source of the hemorrhage to be a cavernous angioma. Because of the location within the brainstem, the decision was made to treat the patient conservatively, and at 6-month follow-up the patient was doing well, with some improvement in his right seventh nerve palsy.
DISCUSSION Seventh cranial nerve palsy is a common diagnosis made in the ED setting. Its idiopathic form, Bell’s palsy, accounts for approximately 50% to 75% of cases. The diagnosis is usually clinical. The typical presentation includes the acute onset (within 1 week) of unilateral paresis of the muscles of facial expression and numbness or heaviness of the affected side without demonstrable sensory deficit. Loss of lacrimation is present in 67% of patients, whereas taste disorders are elicited in 34% of patients. In approximately 50% of patients, pain is present behind the ear. Ipsilateral hyperacusis is found in 14% of cases.1-3 The evaluation of a patient with a seventh cranial nerve palsy generally consists of a thorough medical history and physical examination looking for an identifiable etiology. Laboratory or radiographic studies are considered unnecessary when the presentation is typical. Atypical features include slow onset, Volume 46, no. 1 : July 2005
Sherman & Thompson
Pontine Hemorrhage
Figure 1. Patient demonstrating right seventh cranial nerve palsy when asked to A, show his teeth and B, raise his eyebrows.
otorrhea, vestibular complaints, recent trauma, hearing loss or tinnitus, and other focal neurologic findings.3 Atypical features justify further evaluation, including imaging modalities. When atypical features are present or questions are raised by the medical history or physical examination, other etiologies must be considered. In a study of more than 2,500 patients with a seventh cranial nerve palsy, a total of 37 etiologies were identified, the most common being neonatal, herpes zoster (Ramsey Hunt syndrome), trauma, and diabetes mellitus. Other etiologies commonly cited include Lyme disease, herpes simplex, tumors, multiple sclerosis, sarcoidosis, AIDS, and vascular pontine lesions. Vascular pontine lesions are a rare cause of a seventh nerve palsy, present in only 1% of cases.1 Even more unlikely is a pontine lesion that precipitates an isolated seventh nerve deficit. The seventh cranial nerve lies in close proximity to multiple other important nervous structures within the pons (Figure 3). Commonly injured adjacent structures include the abducens nerve,4 the trigeminal nerve,5 and the vestibular nerve.6 If the medial longitudinal fasciculus is affected, an intranuclear ophthalmoplegia is present in which adduction is impaired on the affected side. A lesion affecting the closely approximated structures of the medial longitudinal Volume 46, no. 1 : July 2005
fasciculus, abducens nerve, and the paramedian pontine reticular formation is known as one-and-a-half syndrome. In this syndrome, the only preserved horizontal eye movement is abduction on the unaffected side. If the seventh cranial nerve is affected additionally, it is termed eight-and-a-half syndrome.7 The case presented here illustrates a deviation from the typical presentation and pathology. Our patient did not have atypical features, nor did he have anything in his history or physical examination that suggested an alternative etiology. A CT scan would not have been ordered by these authors had the patient not given the additional history that an abnormal CT scan of the brain was obtained the preceding day. It is unclear what prompted imaging on the initial visit. It was interesting to note that our patient lacked some of the frequently present symptoms of idiopathic seventh nerve palsy in that he had intact lacrimation and taste, which can be explained by the location of the lesion. The parasympathetic (lacrimation and salivation) and special sensory components (taste) of the seventh cranial nerve are transmitted to the superior salivatory nucleus and nucleus solitarius, respectively. These nuclei, as shown in Figure 3, were in proximity to the lesion in this case but did not affect them. Annals of Emergency Medicine 65
Sherman & Thompson
Pontine Hemorrhage
seventh nerve palsies caused by pontine infarctions. Only 50% of these lesions were identified on MRI, and the remainder were detected by electrophysiologic testing that indicated pontine dysfunction.8 An additional report occurred in a patient with multiple sclerosis.9 One report described an elderly hypertensive man with a pontine hemorrhage noted on MRI in a location similar to that of our patient.10 In conclusion, this case, although rare, is important because it reminds the emergency physician to consider all diagnostic possibilities when evaluating a patient with a seventh cranial nerve palsy. Despite the etiology of the cranial nerve deficit in this case, it would be difficult to recommend routine imaging in cases of isolated seventh nerve palsies. The number of additional imaging studies performed does not seem justified by the rarity of this condition, especially in a young patient with an otherwise typical onset. Supervising editor: William G. Barsan, MD Funding and support: The authors report this study did not receive any outside funding or support. Publication dates: Received for publication November 15, 2004. Revision received December 7, 2004. Accepted for publication December 8, 2004. Available online April 13, 2005. Reprints not available from the authors. Figure 2. CT scan demonstrating a pontine hemorrhage in the right pons just anterior to the fourth ventricle and in the vicinity of the facial nerve nuclei.
Address for correspondence: Scott C. Sherman, MD, Department of Emergency Medicine, Cook County Hospital, 1900 W Polk Avenue, 10th Floor, Chicago, IL 60612; 312-864-0199, fax 312-864-9656; E-mail [email protected]. REFERENCES
Figure 3. Schematic representation of the caudal pons showing the close proximity of nervous structures. CN, Cranial nerve; MLF, medial longitudinal fasciculus; NS, nucleus solitarius; SSN, superior salivatory nucleus; PPRF, paramedian pontine reticular formation. Adapted from Spector and Stark. Arch Neurol. 1983.11
There have been previous reports of cases of isolated seventh nerve palsies caused by pontine lesions. One study of diabetic and hypertensive patients identified 10 patients with isolated 66 Annals of Emergency Medicine
1. Peitersen E. Bell’s palsy: the spontaneous course of 2,500 peripheral facial nerve palsies of different etiologies. Acta Otolaryngol Suppl. 2002;549:4-30. 2. Perry JR, Hasso AN. Magnetic resonance imaging of cranial nerve VII. Top Magn Reson Imaging. 1996;8:155-163. 3. Roob G, Fazekas F, Hartung HP. Peripheral facial palsy: etiology, diagnosis and treatment. Eur Neurol. 1999;41:3-9. 4. Roh JK, Kim BK, Chung JM. Combined peripheral facial and abducens nerve palsy caused by caudal tegmental pontine infarction. Eur Neurol. 1999;41:99-102. 5. Waterman G, Epstein JD, Fenske NA. Herpes zoster infection with trigeminal and facial nerve involvement. Cutis. 1989;43: 262-263. 6. Biavati MJ, Gross JD, Wilson WR, et al. Magnetic resonance imaging evidence of a focal pontine ischemia in sudden hearing loss and seventh nerve paralysis. Am J Otol. 1994;15:250-253. 7. Eggenberger E. Eight-and-a-half syndrome: one-and-a-half syndrome plus cranial nerve VII palsy. J Neuroophthalmol. 1998;18:114-116. 8. Thomke F, Urban PP, Marx JJ, et al. Seventh nerve palsies may be the only clinical sign of small pontine infarctions in diabetic and hypertensive patients. J Neurol. 2002;249:1556-1562. 9. Schnorpfeil F, Braune HJ. Nuclear facial palsy in multiple sclerosis: a case report. Electromyogr Clin Neurophysiol. 1997;37:207-211. 10. Martinez-Garcia FA, Salmeron P, Morales-Ortiz A, et al. [Pontine hemorrhage as a cause of peripheral facial paralysis]. Rev Neurol. 1996;24:984-986. 11. Spector RH, Stark S. Peripheral facial palsy with intact taste and tearing caused by intrapontine lesion. Arch Neurol. 1983; 40:317-319.
Volume 46, no. 1 : July 2005