Kenta Suzuki

Neurofibromatosis type 1-associated extracranial vertebral artery aneurysm complicated by vertebral arteriovenous fistula after rupture: Case report and literature review.

BACKGROUND Extracranial vertebral artery aneurysm related to neurofibromatosis type 1 (NF1) is rare. Aneurysmal rupture typically induces such symptoms as cervical hematoma, hemothorax, and hypotension. Here we report a case of ruptured extracranial vertebral artery aneurysm in a patient with NF1 who, rather than cervical hematoma, hemothorax, or hypotension, developed a vertebral arteriovenous fistula (AVF) after aneurysm rupture. CASE DESCRIPTION A 35-year-old woman with a family history of NF1 presented with sudden-onset right neck and shoulder pain. Computed tomography angiography showed a right extracranial vertebral artery aneurysm. She had neither a cervical hematoma nor hypotension; however, angiography showed an AVF secondary to aneurysmal rupture. The patient was treated with endovascular coil embolization to prevent re-rupture. Postoperatively, her right neck and shoulder pain improved, and she was discharged without further neurologic deficits. CONCLUSIONS This patients clinical course suggests that if there is minimal bleeding from an NF1-associated ruptured extracranial vertebral artery aneurysm, then typical symptoms, such as cervical hematoma, hemothorax, and hypotension, may be absent. Thus, ruptured extracranial vertebral artery aneurysm should be considered in the differential diagnosis of patients with NF1 with sudden-onset radiculopathy, even in the absence of typical symptoms. The detection of a vertebral AVF provides a useful clue to the diagnosis of aneurysm rupture in such cases.

A case of dumbbell-shaped epidural cavernous angioma in the lumbar spine.

Background: Most spinal cavernous haemangiomas occur in the vertebral body and purely extradural cavernous hemangiomas without any vertebral body involvement is rare and account for only 4% of all extradural spinal tumors. Dumbbell-shaped spinal cavernous angioma is extremely rare, only 10 cases have been reported in the literature. Case Description: A 77-year-old female presented with a one-year history of lumbago and right-sided L3 dermatomal hypoesthesia. A dumbbell mass at the L2/3 vertebral level was identified on lumbar MRI. The lesion was irregularly shaped and isointense on T1W and hyperintense on T2W and DWI images with homogenous contrast enhancement. A presumptive diagnosis was schwannoma, but other malignant neoplasms were also considered because of its irregular shape, minimally dilated neural foramen and the involvement of the non-enhanced L3 nerve root. The patient underwent surgery with a lateral extracavitary approach. A histopathological examination revealed cavernous hemangioma. Conclusion: Cavernous hemangioma should be included in the differential diagnosis of dumbbell-shaped spinal tumors when the intervertebral foramina is not highly dilated and non-enhanced nerve root is identified in the tumor.

Importance of Recognizing Carpal Tunnel Syndrome for Neurosurgeons: A Review

Idiopathic carpal tunnel syndrome (CTS) is a common complaint, reflecting entrapment neuropathy of the upper extremity. CTS produces symptoms similar to those of other conditions, such as cervical spondylosis or ischemic or neoplastic intracranial disease. Because of these overlaps, patients with CTS are often referred to a neurosurgeon. Surgical treatment of CTS was started recently in our department. Through this experience, we realized that neurosurgeons should have an increased awareness of this condition so they can knowledgeably assess patients with a differential diagnosis that includes CTS and cervical spinal and cerebral disease. We conducted a literature review to gain the information needed to summarize current knowledge on the clinical, pathogenetic, and therapeutic aspects of CTS. Because the optimal diagnostic criteria for this disease are still undetermined, its diagnosis is based on the patient’s history and physical examination, which should be confirmed by nerve conduction studies and imaging modalities such as magnetic resonance imaging and ultrasonography. Treatment methods include observation, medication, splinting, steroid injections, and surgical intervention. Understanding the clinical features and pathogenesis of CTS, as well as the therapeutic options available to treat it, is important for neurosurgeons if they are to provide the correct management of patients with this disease.

Brain abscess caused by Nocardia asiatica.

Background: Nocardia infection of the central nervous system leading to brain abscess is a rare condition but has a high mortality rate. Among the species of Nocardia, only three cases of brain abscess due to Nocardia asiatica infection have been reported. Case Description: A 65-year-old man with a history of autoimmune hemolytic anemia treated with prednisolone presented to our hospital because of occipital headache. Brain magnetic resonance imaging showed bilateral occipital lesions. The patient underwent craniotomy and resection of the left occipital lobe lesion. N. asiatica was identified by 16S rRNA sequencing of the resected specimen. Treatment with trimethoprim/sulfamethoxazole led to a complete resolution of the brain lesion. Conclusion: Because of the different antimicrobial sensitivity patterns among Nocardia species, both appropriate subtyping and susceptibility testing of uncommon species such as N. asiatica are required for the successful treatment of nocardial infections.

Tandem cervical/intracranial internal carotid artery occlusion due to cardiac myxoma treated successfully with mechanical endovascular thrombectomy.

Dear Editor, Ischemic stroke due to cardiac myxomas is a rare condition without established therapeutic strategies. Acute cervical internal carotid artery (ICA) occlusion due to cardiac myxoma has a poor prognosis, especially when there are tandem lesions caused by intracranial migration of tumorous emboli [3, 8]. Here, we describe the first reported case of a patient with tandem cervical ICA/ICA terminus occlusion subsequent to cardiac myxoma that was successfully treated with mechanical endovascular thrombectomy. A 70-year-old right-handedman who reported sudden right hemiparesis and speech disturbance was transported to our hospital 46 min after symptom onset. His National Institute of Health Stroke Scale (NIHSS) score was 11. Brain magnetic resonance imaging (MRI) using diffusion-weighted imaging demonstrated bilateral multiple small increased-signal lesions due tomultiple small emboli (Fig. 1a). Onmagnetic resonance angiography (MRA) of the head and neck, there was a lack of signal corresponding to the left common carotid artery (CCA) and to the ICA (Fig. 1b, c). Intravenous recombinant tissue plasminogen inhibitor (rtPA) was administered 2 h and 55min after symptom onset but did not achieve neurological improvement. Emergent cerebral angiography was performed via the right femoral artery. Immediately after the start of angiography, the patient’s level of consciousness decreased. Although MRA before rtPA showed collateral flow to the left MCA through the anterior communicating artery, angiography of the right CCA now showed a left carotid T-occlusion (Fig. 1d). Angiography of the left CCA showed left cervical ICA occlusion (Fig. 1e). Together, these results suggested the migration of a large emboli distally into the left ICA terminus, resulting in neurological deterioration. A balloon guide catheter was placed in the left cervical ICA. Three passes with a Penumbra 5MAX ACE catheter (Penumbra, Alameda, CA, USA) resulted in revascularization of the left ICA and the left M1 segment, but the left inferiorM2-branch remained occluded. A single pass with a Trevo retriever (Stryker Neurovascular, Mountain View, CA, USA) resulted in successful recanalization, thrombolysis in cerebral infarction (TICI) grade 2B (Fig. 1f) [5], 6 h and 20 min after symptom onset. The retrieved emboli were whitish-to-reddish, gelatinous, and friable, with a total length >10 cm (Fig. 1g). A postoperative brain MRI showed new symptomatic ischemic lesions in the left MCA territory, but those were limited to the frontal lobe (Fig. 1h). Recanalization of the left ICA and the MCA was observed on MRA (Fig. 1i, j). A pathological examination showed that the retrieved emboli consisted of tumorous tissue from a myxoma (Fig. 1k). Transesophageal echocardiography results confirmed a mass in the left atrium (Fig. 1l). The cardiac mass was resected by open-heart surgery 6 days after the stroke. Three months after the stroke, the patient’s NIHSS score was 1, because of mild aphasia and the modified Rankin Scale score was 2. Although cardiac myxoma is responsible for <1 % of all cases of ischemic stroke [1], it should be considered in the differential diagnosis. The cerebral artery most commonly affected by ischemic stroke due to cardiac myxoma is the MCA (65 %) [12]. ICA involvement by embolic occlusion due to cardiac myxoma is relatively rare (11 %) [12], and cervical ICA occlusion due to cardiac myxoma even rarer. To our knowledge, there are only three reported cases of cervical ICA occlusion subsequent to cardiac myxoma including our * Atsuhito Uneda uneda-oka@umin.ac.jp

Olfactory neuroblastoma followed by emergency surgery for symptomatic intradural spinal metastasis: A case report

Background: Olfactory neuroblastoma (ONB) is a rare, aggressive tumor of the nasal cavity. It may invade the paranasal cavities and anterior skull base locally but may also metastasize to the cervical lymph nodes, lungs, or distant central nervous system. Case Description: Here, we report a case of ONB in which emergency surgery was performed for intradural spinal metastasis (ISM). The patient was a 52-year-old male who underwent surgery for ONB. The tumor extended from the nasal cavity to the intracranial space and was resected completely. After radiotherapy (60 Gy), the patient was discharged without any neurological deficit except anosmia. Seven months after the surgery, he consulted our department because of progressive tetraparesis. Cervical magnetic resonance imaging demonstrated an intradural spinal mass involving C5–T2 and necessitating emergency surgery. The tumor was resected subtotally followed by 58 Gy whole-spine irradiation. The patients neurological symptoms improved, however, paralysis of the right upper and both the lower limbs remained. During the 4 months between the spinal surgery and his death, there was no further motor deterioration in any of his four extremities. Conclusion: This case demonstrates the need to be aware of potential ISM in the follow-up of patients with ONB. The early detection of ISM by spinal MRI is crucial to ensuring good palliative care.

The Importance of Recognizing Diffuse Idiopathic Skeletal Hyperostosis for Neurosurgeons: A Review

Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by calcification and ossification of the soft tissues, mainly ligaments and entheses. The spines of patients with DISH generally become increasingly rigid and osteoporotic, and fractures may occur after even a relatively minor traumatic event such as a ground-level fall. Moreover, the prevalence of DISH may be rapidly increasing in affluent societies. Thus, awareness of this condition is becoming more important for neurosurgeons when assessing trauma patients. For the present article, a literature review was conducted to summarize the current clinical, pathogenetic, and therapeutic knowledge of this disease. Furthermore, current treatment strategies for DISH-related spine injuries are also reviewed. Although the recommended treatment for spinal injuries in DISH patients is surgical, mainly through long-segment posterior fusion, rather than conservative options, stable fractures without any associated neurologic deficits have often been successfully managed with immobilization alone. Percutaneous instrumentation and the use of teriparatide may be useful depending on the surgical risks and patient neurological status.

Cavernous angioma presenting with subarachnoid hemorrhage which was diffusely distributed in the basal cisterns and mimicked intracranial aneurysm rupture

Intracranial cavernous angiomas (cavernomas, cavernous hemangiomas, cavernous malformations) usually cause intraparenchymal hemorrhage but are rarely described as a cause of isolated subarachnoid hemorrhage (SAH).[2,6,10] Some cases of intracranial cavernous angiomas presenting with isolated SAH have been reported.[3,7,9,10,12] However, cavernous angiomas presenting with so-called angiographically negative aneurysmal-like SAH are rare. To our knowledge, only one case of cavernous angioma presenting with perimesencephalic SAH has been reported.[11] We describe a case of cavernous angioma presenting with SAH, which was diffusely distributed in the basal cisterns and mimicked intracranial aneurysm rupture.

Ischemic Tolerance of the Brain and Spinal Cord: A Review

Ischemic tolerance is an endogenous neuroprotective phenomenon induced by sublethal ischemia. Ischemic preconditioning (IPC), the first discovered form of ischemic tolerance, is widely seen in many species and in various organs including the brain and the spinal cord. Ischemic tolerance of the spinal cord is less familiar among neurosurgeons, although it has been reported from the viewpoint of preventing ischemic spinal cord injury during aortic surgery. It is important for neurosurgeons to have opportunities to see patients with spinal cord ischemia, and to understand ischemic tolerance of the spinal cord as well as the brain. IPC has a strong neuroprotective effect in animal models of ischemia; however, clinical application of IPC for ischemic brain and spinal diseases is difficult because they cannot be predicted. In addition, one drawback of preconditioning stimuli is that they are also capable of producing injury with only minor changes to their intensity or duration. Numerous methods to induce ischemic tolerance have been discovered that vary in their timing and the site at which short-term ischemia occurs. These methods include ischemic postconditioning (IPoC), remote ischemic preconditioning (RIPC), remote ischemic perconditioning (RIPerC) and remote ischemic postconditioning (RIPoC), which has had a great impact on clinical approaches to treatment of ischemic brain and spinal cord injury. Especially RIPerC and RIPoC to induce spinal cord tolerance are considered clinically useful, however the evidence supporting these methods is currently insufficient; further experimental or clinical research in this area is thus necessary.

A case of intravascular lymphoma presenting as myelopathy diagnosed with a skin biopsy

Background: Intravascular lymphoma (IVL) is a rare subtype of non-Hodgkin lymphoma with exclusively or predominantly intravascular proliferation. Without therapeutic intervention, the neurologic involvement is rapidly progressive and inevitably fatal. Most of the IVL patients have prominent or exclusive manifestations in the nervous system and there are several reports of patients presenting with spinal symptoms. Case Description: A 68-year-old male patient admitted with the complaints of progressive paraparesis. T2-weighted magnetic resonance imaging (MRI) of the spinal cord showed hyperintense lesions in the thoracic cord. A diagnosis of myelitis of unknown etiology was assumed, and steroid pulse therapy was administered, which temporarily improved the patients symptoms. However, the paraparesis recurred, and other symptoms, such as vertigo, psychosis, and seizures, developed 1-month after the initial treatment. Multiple high-intensity lesions were detected in the bilateral subcortical white matter on DW MRI. Based on the patients clinical course, IVL was suspected; however, obtaining histological confirmation was not possible, as no Gd-enhanced brain or spinal lesions were identified and repeated cerebrospinal fluid examinations were negative for tumor cells. Therefore, a random skin biopsy was performed, and IVL was diagnosed. Obtaining a comparatively favorable outcome was possible owing to the subsequent administration of R-CHOP chemotherapy. Conclusion: IVL should be included in the differential diagnosis of atypical case of presumed myelitis. An early diagnosis and chemotherapy is crucial for improving the patients outcome. When obtaining a diagnosis based on tissues other than skin is difficult, a random skin biopsy should be considered in patients with suspected IVL.