[A Case of Primary Dural Lymphoma of Jugular Tubercle Mimicking Lower Clival Meningioma].

Primary dural lymphoma (PDL) is a rare type of primary central nervous system lymphoma (PCNSL); however, its clinical etiology and appearance on magnetic resonance images (MRI) are similar to those of meningioma. We report a case of PDL mimicking a meningioma in the jugular tubercle, with hemiparesis and double vision, and review the published PDL case reports. A 41-year-old woman experienced numbness on her right side, and reported right hemiparesis and double vision 2 days thereafter. Her cranial computed tomography (CT) scan showed a mass lesion in the posterior fossa, and contrasted MRI revealed homogenous tumor with a dural tail sign in the left jugular tubercle. The patient was diagnosed as having jugular tubercle meningioma. However, her symptoms disappeared promptly with the injection of dexamethasone, and follow-up MRI showed that the tumor had diminished. After 9 months, her double vision recurred and MRI results indicated tumor regrowth. She underwent sub-total resection of the tumor via the left trans-condylar fossa approach. A histological diagnosis was PDL. She was treated with 3 courses of high-dose methotrexate, and subsequent MRI results showed a partial reduction of the residual tumor. PDL is histologically associated with marginal zone lymphoma (MZL), and is sensitive to radiation and chemotherapy. This patient responded well to high-dose methotrexate alone. PDL is one of the important differential diagnoses of meningioma.

Life-Threatening Intracranial Hypotension after Skull Base Surgery with Lumbar Drainage.

Although lumbar drainage (LD) is widely used in skull base surgery (SBS), no cases with intracranial hypotension (IH) following LD-assisted SBS have been reported, and skull base surgeons lack awareness of this potentially life-threatening condition. We report two cases of IH after LD-assisted SBS, a spheno-orbital meningioma and an osteosarcoma in the orbit. Despite a minimal amount of cerebrospinal fluid (CSF) drainage and early LD removal, severe postural headache and even a deteriorating consciousness level were observed in the early postoperative course. Neuroimages demonstrated epidural fluid collections, severe midline shift, and tonsillar sag compatible with IH. Epidural blood patch (EBP) immediately and completely reversed the clinical and radiologic findings in both patients. IH should be included in the differential diagnosis of postural headache after LD-assisted SBS that can be managed successfully with EBP. Persistent leakage of CSF at the LD-inserted site leads to IH. Broad dural dissection and wide removal of bony structure may be involved in the midline shift. EBP should be performed soon after conservative management fails. Further reports will determine the risk factors for IH development following LD-assisted SBS.

[A case of acute intracranial epidural hematoma caused by chronic nasal sinusitis].

Non-traumatic intracranial acute epidural hematoma(EDH)is rare. It is mostly caused by coagulation disorders, dural metastasis, or vascular malformations of the dura. We report a case of non-traumatic acute EDH caused by chronic nasal sinusitis and review the literature comprising 10 cases of acute EDH caused by chronic nasal sinusitis. A 16-year-old boy visited our outpatient clinic with a 2-day history of severe headache. He did not have fever or neurological abnormalities and showed no evidence of head trauma. Cranial computed tomography(CT)revealed sphenoid sinusitis and a small amount of epidural air in the middle fossa, but no other intracranial abnormalities. After eight days with no subsequent history of trauma, radiological exams showed a massive acute epidural hematoma in the left middle fossa and temporal convexity without any vascular lesion or skull fracture. The patient underwent a hematoma evacuation that revealed neither a skull fracture nor a vascular abnormality. In this adolescent, chronic nasal sinusitis caused fragility of the meningeal artery wall, an air collection in the epidural space, and the detachment of the dura mater from the inner surface of the skull, thereby resulting in a non-traumatic acute EDH.

Continuous intraoperative monitoring of abnormal muscle response in microvascular decompression for hemifacial spasm; a real-time navigator for complete relief.

Intermittent monitoring of abnormal muscle response (iAMR) has been reported to be useful for improving the surgical outcome of microvascular decompression (MVD) for hemifacial spasm (HFS). However, iAMR has not elucidated the relationship between AMR change and the corresponding surgical procedure, or the pathogenesis of AMR and HFS. The purpose of this study is to clarify the usefulness of continuous AMR monitoring (cAMR) for improving the surgical results of MVD and for understanding the relationship between AMR change and corresponding surgical procedure, and the pathogenesis of AMR and HFS. Fifty consecutive patients with HFS treated by MVD under cAMR monitoring, which continuously records AMR every minute throughout the surgical period, were retrospectively analyzed. The patients were assessed for the presence of HFS 1 week after the surgery and at final follow-up. Forty-six patients showed the complete disappearance of HFS. In 32, AMR disappeared abruptly and simultaneously with decompression of an offending vessel. AMR showed dynamic and various changes including temporary disappearance, or sudden, gradual, or componential disappearance before and during the decompression procedure, and even during the dural and skin closure after the initial decompression procedure. Facial spasm remained in four patients despite permanent AMR disappearance. cAMR monitoring improves the outcome of MVD. Although the main cause of HFS and AMR is vascular compression at the facial nerve, hyperexcitability of the facial nucleus is also involved in the pathogenesis of HFS and AMR. The proportional involvement of these causes differs between patients.