Bilateral facial colliculus syndrome caused by pontine tegmentum infarction: a case report

Background Bilateral facial colliculus syndrome is a rare clinical presentation in patient with pontine infarction. We herein described a case of bilateral facial paralysis and complete horizontal gaze palsy possibly caused by paradoxical embolization from patent foramen ovale related stroke. Case presentation A 55-year-old male presented with sudden onset of complete peripheral facial palsy and horizontal gaze palsy after Valsava maneuver. MRI revealed symmetric involvement of bilateral pontine tegmentum in accordance with the location of facial colliculus. CSF analysis and follow-up MRI showed no evidence of central demyelinating disease. Subsequent echocardiography revealed patent foramen ovale and closure surgery was performed. Conclusions Facial colliculus syndrome with symmetric dorsal pontine tegmentum involvement may a rare manifestation in posterior circulation stroke.

Sleep Pathophysiology

Sleep is a natural, reversible, and periodic behavioral state characterized by perceptual inattention and decreased responsiveness to external stimuli. The processes governing sleep, sleep-wake transitions, and maintenance of wakefulness are mediated by complex physiologic mechanisms, the primary neurobiological substrates of which include the neocortex, basal forebrain, thalamus, hypothalamus, pontine tegmentum, and brainstem monoaminergic nuclei. Moreover, the integrity of brainstem autonomic respiratory control networks becomes critical in the maintenance of ventilation during sleep. Pathologic insults to these systems may result in a broad constellation of clinical deficits.

Isolated abducens nucleus syndrome due to pontine tegmentum infarction

Introduction: Abnormalities of horizontal gaze could be caused by damage of the abducens nucleus due to ischemic lesion. We report a patient with isolated horizontal gaze palsy as a result of a small ischemic lesion of the pontine tegmentum. Observation: A 61-year-old man, with medical history of diabetes mellitus, dyslipidemia and high blood pressure, was hospitalized after 12 hours of transient dizziness and diplopia. On examination, he had conjugate eye deviation to the right side with horizontal gaze paralysis toward controlateral side. Vertical eye movements, convergence and pupillary reflex were preserved with no peripheral facial palsy. Brain MRI revealed a small lesion in the left pontine tegmentum. Patient received aspirin with atorvastatin and the gaze palsy has been disappeared three weeks later. Discussion: Conjugate lateral eye movement paralysis is commonly attributed to lesions of the caudal pons involving the abducens nucleus. horizontal gaze palsy is often associated to an ipsilateral peripheral facial palsy. In our case, the left lateral gaze palsy was isolated. The pontine lesion should be strictly confined the abducens nucleus which is extremely rare. the outcome of eye movement deviation in brainstem lesions is favorable within few weeks. Conclusion: Our case provides evidence that small pontine lesions can damage the abducens nerve nucleus without causing ipsilateral peripheral facial palsy.

633 Dysregulated REM Sleep in Children with Moebius syndrome

Introduction Moebius syndrome (MBS) is a rare disorder characterized by failure of development of the 6th and 7th cranial nerve nuclei located in the pons. Though the congenital lesion abuts the pontine tegmentum, sleep architecture has not been evaluated in MBS. Methods We report the clinical features of three children with MBS, and discuss implications for “developmental” RBD. Results Three clinically and MRI brain scan-confirmed MBS children, age 0.5 to 16 years, mean 8.5 ± 6.3 years, were evaluated for disrupted sleep, with repetitive crying (1/3), yelling (2/3), agitation in sleep (2/3), and injuring a co-sleeping sibling (1/3); 3/3 had REM sleep without atonia while 2/3 had RBD. REM sleep was reduced in all three: 21.7% in the infant (reference REM percentage value in infancy is about 40%), 11.4% in subject 2 and 3% in subject 3. Treatment with clonazepam (patients 2 and 3) or melatonin (patient 1) had variable results. Conclusion Children with Moebius syndrome have both quantitative (reduced percentage) and qualitative abnormalities of REM sleep (RSWA/RBD). The association of MBS with RSWA/RBD suggests more extensive involvement than published in literature, with extension into the sub-laterodorsal pontine tegmentum and “REM-off” neurons. Moebius syndrome might serve as a model for study of “developmental” REM sleep behavior disorder. Support (if any):

Resection of pontine cavernous malformation by the full neuroendoscopic telovelar approach

Introduction: Lesions located in the fourth ventricle and/or pontine tegmentum were treated by telovelar approach under a microscope. However, it is difficult to access upper fourth ventricle from caudal to rostral without removal posterior arch of the atlas due to the vertical working angle of microscope. Neuroendoscope has a good degree of freedom in surgery and can reach this area easily. We tried to remove pontine cavernous malformation by full neuroendoscopic telovelar approach and the results was excellent. Clinical Presentation: Two women presented with dizziness and numbness and were diagnosed as pontine cavernous malformation. The cavernous malformations were removed by a full neuroendoscopic telovelar approach without removal of the posterior arch of the atlas. Conclusion: Neuroendoscope can remedy the flaws of microscopy and can provide greater application for the telovelar approach in pons and fourth ventricle.