[Cervical retro-odontoid pseudo-tumor treated with posterior decompression surgery].

A cervical retro-odontoid pseudo-tumor, which is considered as a reactive fibrocartilaginous mass, is a rare condition in cervical myelopathy. A 63-year-old male, with repeated neck axial movements by a long-term leisure-time cycling, developed subacute myelopathy. Cervical MRI showed a mass lesion at the retro-odontoid region, compressing to the upper spinal cord. After detailed systemic and local examinations that ruled out primary or metastatic malignancy and inflammatory disorders such as rheumatoid arthritis or chronic kidney diseases, a retro-odontoid pseudo-tumor was diagnosed clinically. The patient underwent posterior C1-laminectomy without tumor resection and its pathological confirmation. After the surgery, his neurological signs of cervical myelopathy improved, and a follow-up MRI one year later showed a mild reduction of the tumor size. The neuro-physicians should recognize the relatively benign pseudotumor in cervical myelopathy, because the tumor size usually shows no further enlargement or regression only after decompression surgery without tumor resection.

[Endogenous endophthalmitis and meningo-encephalitis in septic bacteremia of Klebsiella pneumoniae].

Endogenous endophthalmitis may be a rare condition in acute meningo-encephalitis. A 69-year-old compromised adult abruptly developed septic bacteremia and meningo-encephalitis by Klebsiella pneumoniae. After an improvement from initial conscious disturbance and systemic inflammatory unstable vital conditions by treatment of intensive antibiotic medications, severe unilateral endogenous endophthalmitis with impaired visual acuity was diagnosed by detailed ophthalmological assessments and it deteriorated rapidly. After early vitreous surgery with anti-biotic direct injection, the patient successfully regained visual acuity of 20/200. Among the organisms of endogenous bacterial endophthalmitis, Klebsiella pneumoniae is the worst pathogen mostly resulting in vision loss or enucleation despite any aggressive treatments. The neuro-physicians should recognize the presence of refractory endophthalmitis by Klebsiella pneumoniae, even if clinically asymptomatic, because prompt ophthalmologic diagnosis and managements may improve the outcome.

[Three cases of small brain infarction in the lateral wall of the fourth ventricle presenting with paroxysmal positional vertigo and vomiting].

A lesion responsible for central paroxysmal positional vertigo (PPV) is often found in the dorsolateral wall of the fourth ventricle. A relatively large tumor or hemorrhage in the dorsolateral wall of the fourth ventricle usually causes central PPV, but small brain infarction has hardly been reported to cause central PPV. We report three cases of a small brain infarction in the lateral wall of the fourth ventricle presenting with central PPV. All of the cases showed similar clinical features in which a given recumbent position and a sitting position caused a dizziness associated with nausea and vomiting over an acute period. The symptom lasted one to two months after the onset. In two of our cases, no neurological abnormal signs, except nystagmus, were observed, and initial differentiation of central PPV from peripheral PPV was difficult. Interruption of the vestibular nuclei-archicerebellar loop seems to be responsible for the central PPV. Recognition of the clinical features of central PPV and diffusion-weighted MRI images are important for a precise local diagnosis in small brain infarction showing PPV.