Isolated cranial nerve palsies in multiple sclerosis

Data on patients with multiple sclerosis and cranial nerve involvement as a presenting sign or a sign of disease exacerbation were retrospectively analyzed. Isolated cranial nerve involvement was present in 10.4% out of 483 patients, either as a presenting symptom (7.3%) or a symptom of disease relapse (3.1%). Trigeminal nerve was most frequently involved, followed by facial, abducens, oculomotor and cochlear nerves. Only 54% of patients had brainstem MRI lesion that could explain the symptoms. As multiple sclerosis is a disease characterized by multiple neurological symptoms, while early diagnosis and therapy are critical for the prognosis and course of the disease, the diagnosis of multiple sclerosis should be considered in young adults with cranial nerve involvement.     

Isolated cranial nerve palsies due to brainstem lesions.

Isolated cranial nerve palsies are often attributed to lesions of the respective nerves along their extraaxial courses. There are a significant number of reports of individual patients with cranial nerve palsies, mostly of the 3rd and 6th nerves, as the sole manifestation of brainstem lesions proven by magnetic resonance imaging (MRI) or computer-assisted tomography (CT). An intraaxial basis may still be underestimated if based on MRI only, as electrophysiological abnormalities indicating brainstem lesions (masseter reflex, blink reflex, DC electrooculography) may be independent from MRI-documented morphological lesions. This article reviews the evidence that ischemic and demyelinating brainstem lesions are an important and underestimated cause of clinically isolated cranial nerve palsies. Especially in middle-aged and elderly people with 3rd and 6th nerve palsies, small pontine and mesencephalic infarctions seem to be more frequent than small-vessel ischemic infarctions of the extraaxial nerves.     

Recurrent multiple cranial nerve palsies: a distinctive syndrome of cranial polyneuropathy

This report of 14 Thai patients describes the clinical features of a symptom-complex we have termed recurrent multiple cranial nerve palsies. While the disorder is common in South Eastern Asia, patients suffering similar symptoms have been seen in Europe and America. Characteristically, a long prodromal headache precedes the abrupt onset of multiple cranial nerve palsies affecting predominantly, although not exclusively, the oculomotor and facial nerves. Symptoms are self-limited and steroid therapy hastens recovery in most cases. Recurrence after many months or years is not uncommon and different cranial nerves may then be affected. Wider neurological involvement seems not to occur. Although the erythrocyte sedimentation rate is frequently elevated there is no other evidence of co-existing systemic disease. The single necropsy study thus far reported indicates that the pathogenesis of the syndrome is granulomatous inflammation of the meninges (dura), adjacent to, and involving the perineurium of cranial nerves. It is uncertain whether this inflammation is a response to a single agent, as yet unidentified, or a focal and selective hypersensitivity reaction of connective tissue to a number of different factors. As a clinical entity the syndrome is distinctive, international, and deserving of wide recognition.     

Seronegative granulomatosis with polyangiitis presenting with multiple cranial nerve palsies

Granulomatosis with polyangiitis (GPA), previously known as Wegener’s granulomatosis (WG), is a rare systemic disease characterized by necrotizing granulomas and vasculitis that usually presents in the respiratory tract and renal system. Here, we report a case of anti‐neutrophil cytoplasmic antibody (ANCA)‐negative GPA with diagnostic difficulties. Neurologic involvement in GPA is not uncommon, with up to 50% of patients manifesting with neurologic defects; however, it is usually a late event. This patient was a 50‐year‐old man whose first manifestation was multiple neurologic defects without respiratory or renal symptoms. Since multiple neurologic deficits were the first manifestation and there were no pulmonary or renal symptoms, our patient was treated for 1 year for suspected infectious or inflammatory diseases such as non‐tuberculous mycobacterial infection or immunoglobulin G4 (IgG4)‐related disease with brain involvement; however, his symptoms would wax and wane. Reanalysis of the laboratory findings including biopsies, finally revealed this case to be compatible with GPA. Here, we report a case of GPA, focusing on the diagnostic pitfalls.     

Familial recurrent cranial nerve palsies

Family cases of recurrent cranial nerve palsies are seldom reported. This paper presents a family with recurrent facial and ocular nerve palsies in 2 brothers. Their father and his sister had Bell's palsies. Examinations provided no explanation. Six previous reports of families with recurrent cranial nerve palsies are summarized. The pedigrees speak in favour of an autosomal dominant mode of inheritance of predisposing factors. The pathogenetic mechanism might be vascular or autoimmune, but is still unknown.     

Isolated third nerve palsies

In the diagnostic assessment of patients with N III palsies, the examiner should first endeavor to determine if the palsy is isolated, that is, unassociated with other contributory neurologic findings. If any other abnormalities are present, they should be used to localize the lesion and to help direct ensuing neuroradiologic studies. If the palsy is isolated, the presence of pupil sparing, together with advanced age or a vasculopathic background probably indicates that an extra-axial infarction of the nerve has taken place. The patient may safely be observed periodically without radiographic studies. In younger patients or those without significant vasculopathy, the status of the pupil should not be a major determinant of management. Moreover, the clinician must be aware that pupil sparing is expected when the vulnerable superior division of N III is selectively involved in cavernous sinus compressive lesions. "Pseudo pupil-sparing" in aberrant N III regeneration and in coexisting parasympathetic and sympathetic pupillomotor paresis is a pitfall to be avoided. When one of the muscles subserved by N III appears to be misfunctioning, the diagnosis is rarely that of a partial N III palsy. Instead, the causative lesion is more likely to be in the muscles themselves, the neuromuscular junction, or in the gaze pathways converging on the N III subnuclei.     

Cerebrovascular brainstem diseases with isolated cranial nerve palsies

There is a significant number of individual patients with cranial nerve palsies as the sole manifestation of MRI- and, less frequently, CT-documented small brainstem infarctions or hemorrhages. The 3rd and 6th nerves are most commonly involved and, less frequently, the 4th, 5th, 7th, and 8th nerves. An intra-axial basis for such lesions may be underestimated if the diagnosis is based solely on MRI. The electrophysiologic abnormalities indicating brainstem lesions may be independent of MRI-documented morphological lesions. This paper reviews the literature on cerebrovascular brainstem diseases manifesting as isolated cranial nerve palsies. It supports the concept that small pontine and mesencephalic infarctions are the main cause of non-traumatic cranial nerve palsies in the middle-aged and elderly population. Microvascular infarction of the respective extra-axial cranial nerve segments seem to be less important.     

Microvascular cranial nerve palsies in an Arabic population.

OBJECTIVES: The incidence of microvascular ocular cranial nerve palsies may be increasing with the prevalence of diabetes in the developing world. We review this problem for the first time in an Arabic population. MATERIALS AND METHODS: This is a prospective nonrandomized study of all patients with the diagnosis of microvascular cranial mononeuropathy seen in the Neuro-ophthalmology Clinic at the King Khaled Eye Specialist Hospital between September 1997 and April 1998. RESULTS: Forty-seven patients with microvascular palsies of cranial nerves 3, 4, or 6 were seen in this 8-month period. Compared to previous studies, this group had a stronger association with previously diagnosed diabetes mellitus, more males affected, and a longer duration of the cranial nerve palsy before complete resolution. Five patients had an unusual clinical course that included a second microvascular cranial mononeuropathy before the first palsy completely resolved. CONCLUSIONS: Microvascular cranial nerve palsies may occur more frequently in this Arabic population than elsewhere and may have certain unusual features.     

Spontaneous carotid dissection presenting lower cranial nerve palsies

Cranial nerve palsy in internal carotid artery (ICA) dissection occurs in 3--12% of all patients, but in 3% of these a syndrome of hemicranias and ipsilateral cranial nerve palsy is the sole manifestation of ICA dissection, and in 0.5% of cases there is only cranial nerve palsy without headache. We present two cases of lower cranial nerve palsy. The first patient, a 49-year-old woman, developed left eleventh and twelfth cranial nerve palsies and ipsilateral neck pain. The angio-RM showed an ICA dissection with stenosis of 50%, beginning about 2 cm before the carotid channel. The patient was treated with oral anticoagulant therapy and gradually improved, until complete clinical recovery. The second patient, a 38-year-old woman, presented right hemiparesis and neck pain. The left ICA dissection, beginning 2 cm distal to the bulb, was shown by ultrasound scanning of the carotid and confirmed by MR angiogram and angiography with lumen stenosis of 90%. Following hospitalisation, 20 days from the onset of symptoms, paresis of the left trapezius and sternocleidomastoideus muscles became evident. The patient was treated with oral anticoagulant therapy and only a slight right arm paresis was present at 10 months follow-up. Cranial nerve palsy is not rare in ICA dissection, and the lower cranial nerve palsies in various combinations constitute the main syndrome, but in most cases these are present with the motor or sensory deficit due to cerebral ischemia, along with headache or Horner's syndrome. In the diagnosis of the first case, there was further difficulty because the cranial nerve palsy was isolated without hemiparesis, and the second case presented a rare association of hemiparesis and palsy of the eleventh cranial nerve alone. Compression or stretching of the nerve by the expanded artery may explain the palsies, but an alternative cause is also possible, namely the interruption of the nutrient vessels supplying the nerve, which in our patients is more likely.     

Acute necrosis after Gamma Knife surgery in vestibular schwannoma leading to multiple cranial nerve palsies

We discuss a rare acute complication after Gamma Knife therapy (Elekta AB, Stockholm, Sweden) in a single patient. A 52-year-old woman presented with vertigo, facial weakness and hearing loss emerging 48 hours following Gamma Knife radiosurgery for a right-sided vestibular schwannoma. Neurological examination 6 days after symptom onset showed right-sided facial palsy, spontaneous left-beating nystagmus and pathologic head-impulse testing to the right. Pure-tone audiogram revealed right-sided sensorineural hearing loss. A diagnosis of acute vestibulocochlear and facial neuropathy was made. Brain MRI demonstrated focal contrast sparing within the schwannoma, likely related to acute radiation necrosis. Acute multiple cranial neuropathies of the cerebellopontine angle after Gamma Knife treatment should raise suspicion of acute tissue damage within the schwannoma and should result in urgent MRI. Treatment with steroids may be considered based on accompanying swelling and edema.