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The Earth’s abundance of iron has played a crucial role in both generating its geomagnetic field and contributing to the development of early life. In ancient oceans, iron ions, particularly around deep-sea hydrothermal vents, might have catalyzed the formation of macromolecules, leading to the emergence of life and the Last Universal Common Ancestor. Iron continued to influence catalysis, metabolism, and molecular evolution, resulting in the creation of magnetosome gene clusters in magnetotactic bacteria, which enabled these unicellular organisms to detect geomagnetic field. Although humans lack a clearly identified organ for geomagnetic sensing, many life forms have adapted to geomagnetic field—even in deep-sea environments—through mechanisms beyond the conventional five senses. Research indicates that zebrafish hindbrains are sensitive to magnetic fields, the semicircular canals of pigeons respond to weak potential changes through electromagnetic induction, and human brainwaves respond to magnetic fields in darkness. This suggests that the trigeminal brainstem nucleus and vestibular nuclei, which integrate multimodal magnetic information, might play a role in geomagnetic processing. From iron-based metabolic systems to magnetic sensing in neurons, the evolution of life reflects ongoing adaptation to geomagnetic field. However, since magnetite-activated, torque-based ion channels within cell membranes have not yet been identified, specialized sensory structures like the semicircular canals might still be necessary for detecting geomagnetic orientation. This mini-review explores the evolution of life from Earth’s formation to light-independent human magnetoreception, examining both the magnetite hypothesis and the electromagnetic induction hypothesis as potential mechanisms for human geomagnetic detection.

A 79-year-old woman with a history of resection of the ascending colon cancer presented with conscious disturbance, dysarthria, nausea, and dizziness. Computed tomography (CT) revealed striking high-density lesions in the left cerebellum and left frontal lobe with slight perifocal edema. These lesions were suspected the coexistence of spontaneous cerebellar hemorrhage and frontal lobe metastasis, or multiple brain metastases with massive hematoma. Because of the mass effect of the cerebellar lesion and impaired consciousness, she underwent emergency resection of the cerebellar lesion which was found to be composed of grayish abnormal soft solid tissue and did not include an obvious hematoma mass. The pathological findings were consistent with brain metastasis from colon cancer. This is an impressive rare case of intraoperative solid brain metastasis with a clearly homogenous hyper-dense CT appearance mimicking intracerebral hematoma.

As the average life expectancy increases, neurosurgeons are likely to encounter patients aged 80 years and above with carotid stenosis; however, whether old age affects clinical post-treatment outcomes of carotid endarterectomy (CEA) or carotid artery stenting (CAS) remains inconclusive. Thus, this study aimed to evaluate the outcomes following CEA or CAS in patients aged 80 years and above. This study included older over 80 years (n = 34) and younger patients (

Background: The hyperdense artery sign (HAS) in acute ischemic stroke (AIS) is considered an important marker of a thrombus on computed tomography (CT). An advantage of scanning with dual-energy CT (DECT) is its ability to reconstruct CT images with various energies using the virtual monochromatic imaging (VMI) technique. The aim of this study was to investigate the optimal combination of X-ray energy and slice thickness to detect HASs on DECT. Methods: A total of 32 patients with confirmed occlusion of the horizontal (M1) portion of the middle cerebral artery were included in this study. Modified contrast-to-noise ratio (modified CNR) analysis was used as a method for evaluating HASs in AIS. A region of interest (ROI) was set as an HAS, the M1 portion, and an approximately 2 cm diameter ROI was set as the background including the HAS and measured. CT images with X-ray energies from 40 to 190 keV, with increments of 10 keV, were reconstructed based on VMI with 1, 2, and 3 mm slice thicknesses. Results: The top five combinations of X-ray energy and slice thickness in descending order of the mean HAS-modified CNR were as follows: Rank 1, 60 keV-1 mm; Rank 2, 70 keV-1 mm; Rank 3, 60 keV-2 mm; Rank 4, 80 keV-2 mm; Rank 5, 60 keV-3 mm. Conclusions: Our study showed that the optimal combination to detect an HAS was 60 keV and a 1 mm slice thickness on DECT.

The purpose of this review extends beyond the traditional triune brain model, aiming to elucidate the evolutionary aspects of alpha rhythms in vertebrates. The forebrain, comprising the telencephalon (pallium) and diencephalon (thalamus, hypothalamus), is a common feature in the brains of all vertebrates. In mammals, evolution has prioritized the development of the forebrain, especially the neocortex, over the midbrain (mesencephalon) optic tectum, which serves as the prototype for the visual brain. This evolution enables mammals to process visual information in the retina-thalamus (lateral geniculate nucleus)-occipital cortex pathway. The origin of posterior-dominant alpha rhythms observed in mammals in quiet and dark environments is not solely attributed to cholinergic pontine nuclei cells functioning as a 10 Hz pacemaker in the brainstem. It also involves the ability of the neocortex’s cortical layers to generate traveling waves of alpha rhythms with waxing and waning characteristics. The utilization of alpha rhythms might have facilitated the shift of attention from external visual inputs to internal cognitive processes as an adaptation to thrive in dark environments. The evolution of alpha rhythms might trace back to the dinosaur era, suggesting that enhanced cortical connectivity linked to alpha bands could have facilitated the development of nocturnal awakening in the ancestors of mammals. In fishes, reptiles, and birds, the pallium lacks a cortical layer. However, there is a lack of research clearly observing dominant alpha rhythms in the pallium or organized nuclear structures in fishes, reptiles, or birds. Through convergent evolution, the pallium of birds, which exhibits cortex-like fiber architecture, has not only acquired advanced cognitive and motor abilities but also the capability to generate low-frequency oscillations (4-25 Hz) resembling alpha rhythms. This suggests that the origins of alpha rhythms might lie in the pallium of a common ancestor of birds and mammals.

Background: Pituitary lymphomas (PLs) are very rare, accounting for <0.1% of all intracranial tumors. Of which, PL that is associated with PL is even rarer. Here, we describe a case of PL of a 51-year-old woman that appeared 9 years after pituitary adenoma resection. Case Description: A 51-year-old woman presented with visual disturbance. She had a history of pituitary adenoma resected through endoscopic trans-sphenoidal surgery (eTSS) 9 years before. Although her previous annual follow-up did not show any signs of recurrence, she noticed visual disturbance. One month later, her visual acuity rapidly worsened with headache and fatigue, being referred to our hospital. On examination, she had bilateral quadrantanopia. Her laboratory data showed slightly increased prolactin levels. Magnetic resonance images showed a mass in the sella with suprasellar extension, so she underwent eTSS. The tumor had a fibrous, hard part and a soft gray part, and it was mostly resected. Visual symptoms improved transiently, but ophthalmoplegia appeared 2 weeks after surgery, indicating intrathecal dissemination. Histological analysis confirmed the diagnosis of T-lymphoblastic lymphoma. Positron emission tomography showed tracer accumulation at the pancreas, confirmed as lymphoma through biopsy. However, we could not determine which site of lymphoma was the primary site. She underwent chemotherapy, including cyclophosphamide, vincristine sulfate, doxorubicin hydrochloride, dexamethasone, and methotrexate. The patient died despite several months of treatment. Conclusion: Recurrence of pituitary adenoma cannot be carelessly assumed from a pituitary growing mass after pituitary adenoma resection. PLs have poor prognosis due to their aggressive character. Immediate biopsy and confirmation of the diagnosis are necessary for the treatment of pituitary masses with aggressive features. [ABSTRACT FROM AUTHOR]

Background: Most posttraumatic syringomyelias occur in the cervical or thoracic spinal cord, where they contribute to myelopathic deficits. Here, a 40-year-old patient presented with the left leg monoparesis due to syringomyelia involving the conus medullaris 10 years after an L2 vertebral "crush" fracture. Case Description: Ten years following an L2 vertebral "crush" fracture, a 40-year-old male presented with the new onset of left lower leg paresis. The magnetic resonance imaging showed a T12-L1 syrinx associated with accompanying high-intensity areas above the syrinx located between the T11 and T12 levels. One month after placing a syringosubarachnoid (SS) shunt, both the syrinx and high-intensity area rapidly disappeared, and the left distal motor weakness resolved. Conclusion: Ten years following an L2 "crush" fracture, a 40-year-old male presented with the new onset of a cauda equina syndrome secondary to a posttraumatic T12-L1 syringomyelia causing expansion of the conus medullaris. [ABSTRACT FROM AUTHOR]

Background: This study aimed to directly measure cerebrospinal fluid (CSF) gas tensions and pH before and after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis for moyamoya disease. Methods: This study included 25 patients with moyamoya disease who underwent STA-MCA anastomosis combined with indirect bypass onto their 34 hemispheres. About 1 mL of CSF was collected before and after bypass procedures to measure CSF partial pressure of oxygen (PCSFO2), CSF partial pressure of carbon dioxide (PCSFCO2), and CSF pH with a blood gas analyzer. As the controls, the CSF was collected from 6 patients during surgery for an unruptured cerebral aneurysm. PCSFO2 and PCSFCO2 were expressed as the ratio to partial pressure of oxygen (PaO2) and partial pressure of carbon dioxide (PaCO2), respectively. Results: PCSFO2/PaO2 was 0.79 ± 0.14 in moyamoya disease, being lower than 1.10 ± 0.09 in the controls (P < 0.0001). PCSFCO2/PaCO2 was 0.90 ± 0.10 in moyamoya disease, being higher than 0.84 ± 0.07 in the controls (P = 0.0261). PCSFO2/PaO2 was significantly lower in pediatric patients than in adult patients and in the hemispheres with reduced cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) to acetazolamide than in those with normal CBF but reduced CVR. STA-MCA anastomosis significantly increased PCSFO2/PaO2 from 0.79 ± 0.14 to 0.86 ± 0.14 (P < 0.01) and reduced PCSFCO2/PaCO2 from 0.90 ± 0.10 to 0.69 ± 0.16 (P < 0.0001). There was no difference in CSF pH between moyamoya disease and the controls. Conclusion: PCSFO2/PaO2 was significantly lower in moyamoya disease than in the controls. Its magnitude was more pronounced in pediatric patients than in adult patients and depends on the severity of cerebral ischemia. STA-MCA anastomosis carries dramatic effects on CSF gas tensions in moyamoya patients. CSF may be a valuable biomarker to monitor the pathophysiology of cerebral ischemia/hypoxia in moyamoya disease. [ABSTRACT FROM AUTHOR]

Background: Moyamoya disease often presents white matter hyperintensity (WMH) lesions on fluid-attenuated inversion recovery (FLAIR) images, which is generally accepted as irreversible. We, herein, describe three cases of moyamoya disease with WMH lesions that regressed or disappeared after surgical revascularization. Case Description: This report included two pediatric and one young adult case that developed transient ischemic attacks or ischemic stroke due to bilateral Moyamoya disease. Before surgery, five of their six hemispheres had WMH lesions in the subcortical and/or periventricular white matter on FLAIR images. The lesions included morphologically two different patterns: "Striated" and "patchy" morphology. In all of them, combined bypass surgery was successfully performed on both sides, and no cerebrovascular events occurred during follow-up periods. On follow-up magnetic resonance examinations, the "striated" WMH lesions completely disappeared within six months, while the "patchy" WMH lesions slowly regressed over 12 months Conclusion: Based on radiological findings and the postoperative course of the WMH lesions, the "striated" WMH lesions may represent the inflammation or edema along the neuronal axons due to cerebral ischemia, while the "patchy" WMH lesions may represent vasogenic edema in the white matter through the blood-brain barrier breakdown. Earlier surgical revascularization may resolve these WMH lesions in Moyamoya disease. [ABSTRACT FROM AUTHOR]