Hiroaki Matsumoto

Delayed neuronal cell death in the rat hippocampus is mediated by the mitogen-activated protein kinase signal transduction pathway

Transient global ischemia caused by 5 min of cardiac arrest induced delayed neuronal cell death (apoptosis) in the CA1 region of the rat hippocampus. To characterize the molecular mechanisms that regulate apoptosis in vivo, the contributions to cell death of mitogen-activated protein kinase family members were examined in the hippocampal region after brain ischemia-reperfusion. Ischemia-reperfusion led to a strong activation of the JNK/SAPK (c-Jun NH2-terminal protein kinase/stress activated protein kinase), ERK (extracellular signal-regulated kinase), and p38 enzymes. These results with other previous studies suggest that the activation of JNK/SAPK in accordance with p38 contributes to the induction of apoptosis in CA1 neurons.

The effect of cardiac arrest on the permeability of the mouse blood-brain and blood-spinal cord barrier to pituitary adenylate cyclase activating polypeptide (PACAP)☆

Time-dependent changes in peptide transport system (PTS-6), which transports the 38 amino acid pituitary adenylate cyclase activating polypeptide (PACAP) across the blood-brain barrier (BBB) and blood-spinal cord barrier (BSCB), were studied in mice in a cardiac arrest model. The permeability of the BSCB to radioactivity labeled I131 showed a reversible increase on Day 2-(24 h) after cardiac arrest. The BBB showed no such increase. The increase in BSCB permeability was primarily located within the thoracic region of the spinal cord. We conclude that the ischemia occurring with cardiac arrest results in a transient increase in PTS-6 activity located primarily in the thoracic region of the spinal cord.

Brain metastasis from pancreatic cancer: A case report and literature review.

A 68-year-old man presented to our hospital with a 1-month history of slowly progressing altered mental status and gait disturbance. Magnetic resonance imaging and abdominal computed tomography revealed advanced pancreatic cancer (PC) with brain and para-aortic lymph node metastases. Gross total resection of the brain metastatic tumor was performed. Although symptoms improved, the patient died 3 months postoperatively. In general, the prognosis for PC patients with brain metastasis is very poor. Surgical resection of brain metastasis may play a very limited role in allowing long-term survival of patients for whom the primary PC is controlled or with particular oncocytic-type tumors.

Concomitant Intracranial Chronic Subdural Hematoma and Spinal Subdural Hematoma: A Case Report and Literature Review

BACKGROUNDnConcomitant intracranial chronic subdural hematoma (CSDH) and spinal subdural hematoma (SDH) are rare, and the etiology has yet to be elucidated. However, migration of the hematoma intracranially to a spinal site or coincidence of both intracranial and spinal CSDHs have been proposed as etiologies. We report a case of concomitant intracranial CSDH and spinal SDH in which spinal hematoma might have migrated from the cranial lesion.nnnCASE DESCRIPTIONnA previously healthy 58-year-old man with previous trauma to the occiput and lumbar spine suffered from headache, lumbago, and left hemiparesis. Head computed tomography revealed right-sided intracranial CSDH, and he underwent single burr-hole craniotomy. Although clinical symptoms tended to improve, left lower-limb weakness and lumbago remained. Spinal magnetic resonance imaging (MRI) 3 days after craniotomy revealed SDH extending from T1-S1. Because conservative therapy had not improved clinical symptoms, hematoma evacuation was performed via a left L5 hemilaminectomy 1 week after craniotomy. The patient showed complete recovery immediately postoperatively.nnnCONCLUSIONSnWe reviewed the cases of 22 patients with concomitant intracranial CSDH and spinal SDH to discuss the features, etiology, and treatment strategy. Although surgical intervention was mainly selected for intracranial CSDH, conservative observation was mainly selected for spinal SDH. Outcomes were good in all patients. We created a new classification of spinal SDH shape using sagittal MRI. This classification indicates that cases with both ventral and dorsal SDH tend to require surgical intervention. This classification may help in deciding treatment strategies.

Clinical investigation of chronic subdural hematoma with impending brain herniation on arrival

Chronic subdural hematoma (CSDH) with brain herniation signs is rarely seen in the emergent department. As such, there are few cumulative data to analyze such cases. In this study, we evaluated the clinical features, risk factors, and rates of completion with impending brain herniation on arrival in a cohort study. We analyzed 492 consecutive patients with CSDH between January 2010 and October 2015. First, we analyzed the clinical factors and compared them between patients with or without brain herniation signs on admission. Second, we compared clinical factors between patients with or without completion of brain herniation after operation among patients who had brain herniation signs on arrival. Eleven (2.2%) patients showed brain herniation signs on arrival, and six patients (1.2%) progressed to complete brain herniation. Patients with brain herniation signs on arrival were significantly older (Pxa0=xa00.03) and more frequently hospitalized with a concomitant illness (Pxa0<xa00.0001). Niveau formation (Pxa0=xa00.0005) and acute-on CSDH (Pxa0=xa00.0001) on computed tomography were also more frequently seen in patients with brain herniation signs. Multivariate logistic regression analysis showed that age older than 75xa0years (OR 2.16, Pxa0<xa00.0001), niveau formation (OR 3.09, Pxa0<xa00.0001), acute-on CSDH (OR 14, Pxa0<xa00.0001), and admitted to another hospital (OR 52.6, Pxa0<xa00.0001) were independent risk factors for having had brain herniation signs on arrival. On the other hand, having a history of head injury (Pxa0=xa00.02) and disappearance of the ambient cistern (Pxa0=xa00.0009) were significantly associated with completion of brain herniation. The prognosis was generally poor if the patient had presented with brain herniation signs on admission. Our results demonstrate that the diagnosis is often made late, despite hospitalization for a concomitant illness. When the elderly show mild disturbance of consciousness, physicians except neurosurgeons need to consider the possibility of CSDH regardless of a recent history of head injury.

Cerebellar Enterogenous Cyst with Atypical Appearance and Pathological Findings

BACKGROUNDnIntracranial enterogenous cysts are rare and occur mainly in the posterior fossa. These cysts are usually extra-axial, midline, anterior to the brainstem, or at the cerebellopontine angle. Intracranial intra-axial enterogenous cysts are extremely rare. We report a case of an intra-axial cerebellar enterogenous cyst in which diagnosis was difficult because the lesion resembled an arachnoid cyst in appearance and showed atypical pathologic findings.nnnCASE DESCRIPTIONnA 69-year-old woman had a 2-year history of progressive headache, giddiness, and unsteadiness of gait. Magnetic resonance imaging showed a cystic lesion with isointensity to cerebrospinal fluid in the left cerebellar hemisphere, reaching into the fourth ventricle. The patient underwent fenestration of the cyst and creation of a communication between the fourth ventricle and cyst because the tight attachment of the cyst wall to the cerebellum prevented total removal of the cyst. Although pathologic examinations did not show findings typical of enterogenous cyst, the diagnosis was finally made based on the presence of basement membrane and immunohistochemical results.nnnCONCLUSIONnThe diagnosis of enterogenous cyst is based mainly on histologic findings, because characteristic findings on neuroimaging have not been defined. Although total resection of enterogenous cysts is recommended in general, partial resection while ensuring the cyst communicates adequately with the surrounding cerebrospinal fluid space with or without a shunt procedure may be useful if the cyst is adherent to surrounding neurovascular structures.

Validation of a Metal Artifact Reduction Algorithm Using 1D Linear Interpolation for Cone Beam CT after Endovascular Coiling Therapy for Cerebral Aneurysms

This study aimed to evaluate the effect of a metal artifact reduction (MAR) algorithm using 1D linear interpolation on cone-beam CT (CBCT). We performed phantom and clinical qualitative studies with and without MAR application using 1D linear interpolation. In the phantom study, the standard deviation (SD) was estimated from the images obtained from the water phantom in which a metal coil was placed at the center, and observed the changes in the SDs before and after MAR application. In the clinical qualitative study, the clinical images after endovascular treatment (EVT) for cerebral aneurysms were visually evaluated before and after MAR application. In the phantom study, the SDs after MAR application decreased by 56 to 35% compared with that before MAR application. In the clinical qualitative study, the artifacts from the metal coil decreased or increased depending on locations, and the contrasts of gray matter and white matter were attenuated when MAR was applied. In conclusion, the metal artifact decreases when MAR using 1D linear interpolation is applied to cerebral CBCT. However, another artifacts increase or soft tissue contrast is changed in some cases. MAR largely contributes to the reduction of streaking artifacts, whereas it may induce cerebral parenchyma at distant metal body or quality deterioration of the image not including the metal body. This should be taken into account in the diagnosis of secondary hemorrhage or infarction.

Clinical Investigation of Refractory Chronic Subdural Hematoma: A Comparison of Clinical Factors Between Single and Repeated Recurrences

BACKGROUNDnChronic subdural hematoma (CSDH) is sometimes refractory, and this is troublesome for neurosurgeons. Although many studies have reported risk factors or treatments in efforts to prevent recurrence, those have focused on single recurrence, and few cumulative data are available to analyze refractory CSDH.nnnMETHODSnWe defined refractory CSDH as ≥2 recurrences, then analyzed and compared clinical factors between patients with single recurrence and those with refractory CSDH in a cohort study, to clarify whether patients with refractory CSDH experience different or more risk factors than patients with single recurrence, and whether burr-hole irrigation with closed-system drainage reduces refractory CSDH.nnnRESULTSnSeventy-five patients had at least 1 recurrence, with single recurrence in 62 patients and ≥2 recurrences in 13 patients. In comparing clinical characteristics, patients with refractory CSDH were significantly younger (Pxa0= 0.04) and showed shorter interval to first recurrence (P < 0.001). Organized CSDH was also significantly associated with refractory CSDH (Pxa0= 0.02). Multivariate logistic regression analysis identified first recurrence interval <1 month (odds ratio, 6.66, P < 0.001) and age <71 years (odds ratio, 4.16, P < 0.001) as independent risk factors for refractory CSDH. On the other hand, burr-hole irrigation with closed-system drainage did not reduce refractory CSDH.nnnCONCLUSIONSnWhen patients with risk factors for refractory CSDH experience recurrence, alternative surgical procedures may be considered as the second surgery, because burr-hole irrigation with closed-system drainage did not reduce refractory CSDH in our study.

Which surgical procedure is effective for refractory chronic subdural hematoma? Analysis of our surgical procedures and literature review

Refractory chronic subdural hematoma (CSDH) is rare but remains a difficulty for neurosurgeons, and no consensus on treatment procedures has been established. To discuss effective surgical procedures for refractory CSDH, we analyzed our surgical procedures and outcomes for refractory CSDH. We defined patients with refractory CSDH as those who presented with two or more recurrences. Fourteen patients with refractory CSDH were analyzed. Eight patients underwent burr-hole irrigation and closed-system drainage alone, four patients received embolization of the middle meningeal artery (MMA), and two patients with organized CSDH underwent large craniotomy with outer membranectomy as the third surgery. Two of the eight patients (25%) treated with burr-hole irrigation and drainage alone showed a third recurrence. No further recurrences were identified in patients treated with embolization of the MMA or craniotomy. However, statistical analysis showed no significant difference in cure rate between patients treated with burr-hole irrigation and drainage alone and patients treated with burr-hole irrigation and drainage with embolization of the MMA (Pu202f=u202f.42). Similarly, no significant differences in cure rate were seen between patients treated with burr-hole irrigation and drainage alone and patients treated with craniotomy (Pu202f=u202f.62). When selecting a surgical procedure, assessing whether the CSDH is organized is crucial. Embolization of the MMA may be considered as one of the optional treatments for refractory CSDH without organized hematoma. On the other hand, for refractory cases of organized CSDH, hematoma evacuation and outer membranectomy with large craniotomy or mini-craniotomy assisted by an endoscope may be suitable, as previous reports have recommended.

Development of Glioblastoma after Treatment of Brain Abscess

OBJECTIVEnAbscess formation within a glioblastoma has been reported rarely. In the few reported cases, after aspiration to treat a presumed abscess, lesions recurred over a short period and, consequently, glioblastoma was recognized. We present a case of a glioblastoma that developed 1.5 years after successful treatment of a brain abscess. A latency of 1.5 years before symptom development seems overly long, even if the glioblastoma was present at the time of the initial brain abscess. Hence, we consider this a possible de novo glioblastoma arising from glial scar tissue. We also discuss possible mechanisms underlying malignant transformation.nnnCASE DESCRIPTIONnA 78-year-old man was admitted to our hospital with progressive gait disturbance caused by a brain abscess. Aspiration of the cyst and systematic antibiotic therapy cured the abscess. However, 1.5 years later, the patient presented to our hospital with generalized convulsions due to recurrence of the cystic lesion. He underwent craniotomy for removal of the cystic lesion, which was found to be a glioblastoma rather than a recurrent brain abscess. Glial scar tissue was detected in the cyst wall.nnnCONCLUSIONSnDevelopment of glioblastoma after treatment of a brain abscess is rare; the pathogenesis is open to speculation. Based on the clinical course, the pathologic findings, and comparison with previous reports, de novo glioblastoma arising from glial scar tissue may be the most likely explanation of the current case. If so, to our knowledge, this is the first report of this condition.