Pretreatment with Clodronate Improved Neurological Function by Preventing Reduction of Posthemorrhagic Cerebral Blood Flow in Experimental Subarachnoid Hemorrhage.

BACKGROUND: Brain perivascular macrophages (PVMs) are potential treatment targets for subarachnoid hemorrhage (SAH), and previous studies revealed that their depletion by clodronate (CLD) improved outcomes after experimental SAH. However, the underlying mechanisms are not well understood. Therefore, we investigated whether reducing PVMs by CLD pretreatment improves SAH prognosis by inhibiting posthemorrhagic impairment of cerebral blood flow (CBF). METHODS: In total, 80 male Sprague-Dawley rats received an intracerebroventricular injection of the vehicle (liposomes) or CLD. Subsequently, the rats were categorized into the prechiasmatic saline injection (sham) and blood injection (SAH) groups after 72 h. We assessed its effects on weak and severe SAH, which were induced by 200- and 300-µL arterial blood injections, respectively. In addition, neurological function at 72 h and CBF changes from before the intervention to 5 min after were assessed in rats after sham/SAH induction as the primary and secondary end points, respectively. RESULTS: CLD significantly reduced PVMs before SAH induction. Although pretreatment with CLD in the weak SAH group provided no additive effects on the primary end point, rats in the severe SAH group showed significant improvement in the rotarod test. In the severe SAH group, CLD inhibited acute reduction of CBF and tended to decrease hypoxia-inducible factor 1α expression. Furthermore, CLD reduced the number of PVMs in rats subjected to sham and SAH surgery, although no effects were observed in oxidative stress and inflammation. CONCLUSIONS: Our study proposes that pretreatment with CLD-targeting PVMs can improve the prognosis of severe SAH through a candidate mechanism of inhibition of posthemorrhagic CBF reduction.

Central sympathetic nerve activation in subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is a life-threatening condition, and although its two main complications-cerebral vasospasm (CVS)/delayed cerebral ischemia (DCI) and early brain injury (EBI)-have been widely studied, prognosis has not improved over time. The sympathetic nerve (SN) system is important for the regulation of cardiovascular function and is closely associated with cerebral vessels and the regulation of cerebral blood flow and cerebrovascular function; thus, excessive SN activation leads to a rapid breakdown of homeostasis in the brain. In the hyperacute phase, patients with SAH can experience possibly lethal conditions that are thought to be associated with SN activation (catecholamine surge)-related arrhythmia, neurogenic pulmonary edema, and irreversible injury to the hypothalamus and brainstem. Although the role of the SN system in SAH has long been investigated and considerable evidence has been collected, the exact pathophysiology remains undetermined, mainly because the relationships between the SN system and SAH are complicated, and many SN-modulating factors are involved. Thus, research concerning these relationships needs to explore novel findings that correlate with the relevant concepts based on past reliable evidence. Here, we explore the role of the central SN (CSN) system in SAH pathophysiology and provide a comprehensive review of the functional CSN network; brain injury in hyperacute phase involving the CSN system; pathophysiological overlap between the CSN system and the two major SAH complications, CVS/DCI and EBI; CSN-modulating factors; and SAH-related extracerebral organ injury. Further studies are warranted to determine the specific roles of the CSN system in the brain injuries associated with SAH.

Endoscopic aqueductal membrane fenestration was effective for intractable hydrocephalus after removal of a nongerminomatous germ cell tumor exhibiting growing teratoma syndrome: a case report.

BACKGROUND: Primary central nervous system (CNS) germ cell tumors (GCTs) are rare neoplasms predominantly observed in the pediatric and young adult populations. A mixed GCT including immature teratoma exhibiting growing teratoma syndrome is presented. The pathogenesis of growing teratoma syndrome remains unclear, and its treatment strategy has not been established. GCTs are often located within the ventricles, causing hydrocephalus, which sometimes improves after removal of the tumor due to restoration of cerebrospinal fluid (CSF) flow. On the other hand, even if the flow route of CSF from the third ventricle to arachnoid granulations on the brain surface quadrigeminal cistern is restored after removal of the tumor, hydrocephalus may not improve. CASE PRESENTATION: A case whose intractable hydrocephalus improved after penetrating the aqueductal membrane via endoscopy is described. An 11-year-old boy was treated for pineal intracranial growing teratoma syndrome (IGTS). The tumor grew rapidly in a short period, and hydrocephalus progressed despite endoscopic third ventriculostomy (ETV). Although the obstruction was removed by radiation, chemotherapy, and total tumor resection, the hydrocephalus did not improve. Endoscopic membrane perforation was performed because a membrane-like structure was seen at the entrance of the cerebral aqueduct on magnetic resonance imaging. The hydrocephalus improved immediately after the operation, and the patient's consciousness disturbance also improved significantly. CONCLUSION: The purpose of this report is to update the current knowledge and standards of management for patients with growing teratoma syndrome, as well as to drive future translational and clinical studies by recognizing the unmet needs concerning hydrocephalus.

Persistent brain exposure to high sodium induces stroke onset by upregulation of cerebral microbleeds and oxidative stress in hypertensive rats.

High salt intake induces hypertension and enhances stroke onset. However, whether an increase in brain sodium exposure itself is harmful and has poor prognosis remains unknown. Therefore, we employed hypertensive rats that underwent intracerebroventricular (ICV) infusion of sodium for 28 days and evaluated stroke onset and related cytotoxic brain injuries. Forty-seven spontaneously hypertensive stroke-prone (SHRSP) and 39 normotensive rats (Wistar Kyoto rats [WKY]) underwent persistent ICV infusion of the following four solutions: artificial cerebrospinal fluid, 0.9%, 2.7%, and 9% saline for 28 days. We evaluated stroke onset and all-cause mortality between SHRSP and WKY at each ICV sodium concentration as the primary endpoints. Our secondary objective was to explore histological brain injuries associated with SHRSP induced by high sodium ICV. The results indicated that ICV infusion of 2.7% and 9% sodium showed a significant increase in stroke onset, decrease in body weight, and increase rate of brain water content in SHRSP compared to WKY. Increased blood pressure was not observed for ICV infusion of high sodium, while serum sodium concentration was significantly increased in SHRSP compared to WKY. Histological evaluations revealed that higher sodium infusion significantly increased the number of activated microglia, superoxide, neuronal cell loss, and microbleeds compared to WKY and SHRSP with 0.9% sodium. We conclude that persistent exposure to high sodium in the brain is one of the risk factors for stroke onset upregulating cerebral microbleeds and oxidative stress in hypertensive rats.

A Ruptured Aneurysm of the Transdural Anastomotic Artery Occurring at the Temporal Base in Moyamoya Disease: Case Report and Literature Review.

A 24-year-old woman with hemorrhagic onset moyamoya disease received bilateral indirect bypass surgery 11 years ago. She presented with a life-threatening atraumatic acute right subdural hematoma with temporal lobe intracerebral hemorrhage due to a transdural anastomosis (TDA) aneurysm rupture. We reviewed six cases of rare TDA aneurysms, all of which occurred around the temporal base. TDA aneurysms may occur near the main trunk of the middle meningeal artery (MMA) where hemodynamic stress is high. Therefore, we must pay attention to skull base aneurysms that form near the MMA; otherwise, the prognosis would be poor if such an aneurysm ruptured.

Leakage sign is a reliable predictor of hematoma expansion in acute epidural hematoma.

BACKGROUND: Hematoma expansion in small/medium-sized acute epidural hematoma (AEDH) cases upon emergency admission is critical. Predicting hematoma expansion can lead to early surgical interventions, improving outcomes and eliminating the need to check for expansion via computed tomography (CT). This study aimed to identify the most reliable predictors of AEDH expansion. METHODS: We retrospectively collected data from patients with pure AEDH not requiring surgical treatment upon emergency admission from 2012-2022. We assessed clinical and laboratory data, time from injury to the first CT, and time to follow-up CT. Factors predictive of hematoma expansion on the second follow-up CT, including the leakage sign (LS), were analyzed. RESULTS: A total of 23 patients with pure AEDH without surgery at admission were included, and LS was positive in 18. Thirteen patients showed hematoma expansion. The hematoma expansion group showed a significantly higher rate of positive LS and lower mean platelet count than the group without hematoma expansion. LS's predictive value for AEDH expansion showed 100% sensitivity and 50% specificity. All patients with negative LS and normal platelet counts showed no hematoma expansion. Analyzing the time from injury to the first CT suggested that LS (+) within 120 min strongly predicted hematoma expansion. Reconstructed three-dimensional images of the leakage point on the skull revealed multiple mottled bleeding points on the dural surface. CONCLUSION: LS can predict hematoma expansion in patients with pure AEDH for whom emergency surgery is unnecessary at admission. The time from injury and platelet counts must also be considered.

Microscopic observation of morphological changes in cerebral arteries and veins in hyperacute phase after experimental subarachnoid hemorrhage: an in-vivo analysis.

This observational study examined morphological changes in superficial cerebral arteries and veins, which were correlated with increased intracranial pressure (ICP)-dependent and -independent hypoperfusion in hyperacute phase after subarachnoid hemorrhage (SAH). The prechiasmatic injection model was used, and 32 male Sprague-Dawley rats were divided into the sham-operated, saline-injected (V group, ICP increase), and arterial blood-injected (SAH group, subarachnoid blood and plus increase) groups. Morphological changes in cortical arteries and veins were observed through the cranial window with a microscope before and up to 10 min after the injection. At 24 h, the stenotic and obstructive cortical arteries and veins were counted. After 6 min, 60% of rats in the V group showed vasodilatation, whereas all rats in the SAH group demonstrated vasodilation and vasoconstriction (arterial instability) within 10 min. Similar acute venous congestive changes were observed within 10 min in the V and SAH groups. At 24 h, stenotic and obstructive arteries and veins were observed in the SAH group. Neurological deteriorations were observed at 1 h in the V and SAH groups, and at 23 h in the SAH group. The sham-operated group showed no evident vascular changes and neurological deterioration. The same phenomena, including arterial changes after 6 min and immediate venous changes in the V and SAH groups, may have resulted from ICP increase, whereas subarachnoid blood-related factors produced arterial instability within 5 min after blood injection. Subarachnoid blood plays a significant role in hyperacute SAH pathophysiology in addition to ICP increase.

Bold-S Signs on Computed Tomography Angiography Are Sensitive Markers for Diagnosing Subcortical Hemorrhage Due to Dural Arteriovenous Fistulae on Emergent Admission.

An optimal treatment strategy for subcortical hematomas caused by dural arteriovenous fistulae (dAVF) is important because of the high rebleeding rate. However, it is very difficult to diagnose that on admission. Therefore, an early sensitive predictive marker for subcortical hemorrhage caused by dAVF is necessary, especially during the first contact on admission. S-shaped dilated vessels around the hematoma (bold-S sign) on computed tomography angiography (CTA) performed during admission could be one such marker. Herein, we evaluated the characteristics of these vessels. Among 273 patients with intracerebral hemorrhage between April 2012 and March 2020, 67 patients with subcortical hematomas who underwent CTA on admission without arteriovenous malformations were included. The patients in the dAVF group (n = 7) showed fewer disturbances in consciousness, milder neurological deficits, and more frequent seizures than patients without dAVF (without dAVF group, n = 60). All patients in the dAVF group had dilated S-shaped vessels (2.59 ± 0.27 mm) around the hematomas, and only 20% of the patients in the without dAVF group had these vessels (1.69 ± 0.22 mm). The ratio of the ipsilateral S-shaped/contralateral largest vessels was 1.80 ± 0.29 in the dAVF group and 1.07 ± 0.16 in the group without dAVF. We called the dilated S-shaped vessels the "bold-S sign," with a cutoff ratio of 1.5. Bold-S sign findings are novel and help in diagnosing subcortical hematomas caused by dAVF on admission.

Effects of Microvascular Decompression on Pain Relief and Quality of Life in Late Elderly Patients with Trigeminal Neuralgia.

Pharmacotherapy is frequently selected over surgical interventions for late elderly patients with trigeminal neuralgia (TN). However, medication may affect these patients' activities of daily living (ADL). Hence, we investigated the effect of the surgical treatment of TN on ADL in older patients. This study included 11 late elderly patients >75 years old and 26 nonlate elderly patients who underwent microvascular decompression (MVD) for TN at our hospital from June 2017 to August 2021. We evaluated pre- and postsurgical ADL using the Barthel Index (BI) score, side effects of antineuralgic drugs, the BNI pain intensity score, and perioperative medication. The BI score of late elderly patients significantly improved postoperatively, particularly in transfer (pre: 10.5; post: 13.2), mobility (pre: 10; post: 12.7), and feeding (pre: 5.9 points; post: 10 points). Additionally, antineuralgic drugs caused preoperative disturbances of transfer and mobility. Trends of a longer disease duration and frequent occurrence of side effects were observed in all patients in the elderly group, compared to only 9 out of 26 patients in the younger group (100% vs. 35%, p = 0.0002). In addition, drowsiness was observed more frequently in the late elderly group (73% vs. 23%, p = 0.0084). However, the change in scores indicating improvement after surgery was significantly greater in the late elderly group, although both pre- and postoperative scores were higher in the nonlate elderly group (11.4 ± 1.9 vs. 6.9 ± 0.7, p = 0.027). Surgical treatment can improve older patients' ADL because it relieves pain and facilitates discontinuation of antineuralgic drugs. Consequently, MVD can be positively recommended for older patients with TN if general anesthesia is acceptable.

Visual Outcomes and Surgical Approach Selection Focusing on Active Optic Canal Decompression and Maximum Safe Resection for Suprasellar Meningiomas.

The goal of treating patients with suprasellar meningioma is improving or preserving visual function while achieving long-term tumor control. We retrospectively examined patient and tumor characteristics and surgical and visual outcomes in 30 patients with a suprasellar meningioma who underwent resection via an endoscopic endonasal (15 patients), sub-frontal (8 patients), or anterior interhemispheric (7 patients) approach. Approach selection was based on the presence of optic canal invasion, vascular encasement, and tumor extension. Optic canal decompression and exploration were performed as key surgical procedures. Simpson grade 1 to 3 resection was achieved in 80% of cases. Among the 26 patients with pre-existing visual dysfunction, vision at discharge improved in 18 patients (69.2%), remained unchanged in six (23.1%), and deteriorated in two (7.7%). Further gradual visual recovery and/or maintenance of useful vision were also observed during follow-up. We propose an algorithm for selecting the appropriate surgical approach to a suprasellar meningioma based on preoperative radiologic tumor characteristics. The algorithm focuses on effective optic canal decompression and maximum safe resection, possibly contributing to favorable visual outcomes.

Pediatric acute epidural hematoma caused by contrecoup injury: illustrative case.

BACKGROUND: Acute epidural hematomas (AEDHs) are formed by injury of the middle meningeal artery or venous sinus with a linear fracture just above these blood vessels. The incidence of AEDH without fracture is low, and the formation of an acute epidural hematoma due to contrecoup injury is even rarer. Here, the authors report a case of pediatric AEDH due to contrecoup injury. OBSERVATIONS: A 6-year-old boy was injured in a traffic accident and was ejected from of the car. At admission, he was clearly conscious without obvious neurological deficits. Computed tomography (CT) revealed a small fracture in the right occipital lobe and a thin epidural hematoma in the contralateral left frontal lobe. A CT scan 3 hours later showed an expanded AEDH. Furthermore, the patient presented with progressive disturbance of consciousness. An emergency craniotomy was performed, but no obvious bleeding point or fracture was observed. LESSONS: The source of bleeding in AEDH due to contrecoup injury in the frontal region is thought to be due to microvessel injury in the dura. Anatomical fragility and the amount of energy transferred causing the injury are associated with the AEDH formation due to contrecoup injury; thus, strict management in high-energy trauma is required.

Efficacy of a Novel Prophylactic Barbiturate Therapy for Severe Traumatic Brain Injuries: Step-down Infusion of a Barbiturate with Normothermia.

This study aimed to examine the beneficial effects of a novel prophylactic barbiturate therapy, step-down infusion of barbiturates, using thiamylal with normothermia (NOR+sdB), on the poor outcome in the patients with severe traumatic brain injuries (sTBI), in comparison with mild hypothermia (MD-HYPO). From January 2000 to March 2019, 4133 patients with TBI were admitted to our hospital. The inclusion criteria were: a Glasgow coma scale (GCS) score of ≤8 on admission, age between 20 and 80 years, intracranial hematoma requiring surgical evacuation of the hematoma with craniotomy and/or external decompression, and patients who underwent management of body temperature and assessed their outcome at 6-12 months. Finally, 43 patients were included in the MD-HYPO (n = 29) and NOR+sdB (n = 14) groups. sdB was initiated intraoperatively or immediately after the surgical treatment. There were no significant differences in patient characteristics, including age, sex, past medical history, GCS on admission, type of intracranial hematoma, and length of hospitalization between the two groups. Although NOR+sdB could not improve the patient's poor outcome either at discharge from the intensive care unit (ICU) or at 6-12 months after admission, the treatment inhibited composite death at discharge from the ICU. The mean value of the maximum intracranial pressure (ICP) in the NOR+sdB group was <20 mmHg throughout the first 120 h. NOR+sdB prevented composite death in the ICU in patients with sTBI, and we may obtain novel insights into the beneficial role of prophylactic barbiturate therapy from suppression of the elevated ICP during the first 120 h.

Venous Anatomy of the Cavernous Sinus and Relevant Veins.

The cavernous sinus (CS) is a dural sinus located on each side of the pituitary fossa. Neoplastic and vascular lesions, such as arteriovenous fistulas, frequently involve the CS. This sinus plays a role as a crossroad receiving venous blood flow from the facial, orbital, meningeal, and neural venous tributaries. The relationship between these surrounding relevant veins and the CS, as well as the CS itself, varies anatomically. For safe and effective surgical and endovascular treatment of lesions involving the CS, knowledge of the anatomy and variations of the CS and the relevant surrounding veins is highly important. In this section, the anatomy and variations of the CS and the relevant surrounding veins are outlined.

Additional Embolization for Intra-aneurysmal Blood Flow Resumption after Stent-assisted Embolization of Cerebral Aneurysms.

Objective: Stent-assisted aneurysmal embolization (SAAE) is an effective treatment for aneurysms with a low risk of recurrence. In rare cases, retreatment is necessary due to recanalization of blood flow into the aneurysm. However, only a few studies have reported on retreatment. We examined the efficacy and complications of stent-assisted aneurysm embolization for large or wide-neck aneurysms at our hospital. Methods: Between July 2010 and June 2018, 293 patients underwent stent-assisted aneurysm embolization at our hospital. Among them, 12 (2 women, 10 men, mean age: 62 years) needed retreatment. We evaluated the initial treatment of these 12 patients, and the methods and results of their retreatment. Results: Six of the 12 retreated patients were treated using the simple technique. It was possible to treat nine patients (75%) without placing new stents, but three needed additional stents. We were able to guide the microcatheter into the aneurysm using the trans-cell technique even with two overlapping stents. We achieved complete embolism in seven patients (58%), and remnants were observed in the neck in five (42%) patients. No complications were associated with our surgery. We were able to perform follow-up for 10 patients and there was no recurrence. Conclusion: Embolization should be considered in recurrent cases after the initial stent-assisted coil embolization. We achieved good results and reduced the recurrence rate by selecting the appropriate treatment in each case.

Leptomeningeal Carcinomatosis After Neoplastic Cerebral Aneurysm Rupture.

BACKGROUND: Several possible mechanisms exist for the spread of a primary tumor to the leptomeninges in leptomeningeal carcinomatosis. This report describes a case caused by direct bleeding in the subarachnoid space from a neoplastic cerebral aneurysm rupture. CASE DESCRIPTION: A 48-year-old Japanese woman, who was diagnosed with breast carcinoma (pT3 pN2 M0) at the age of 45 years and underwent mastectomy and chemotherapy, was admitted in a coma following a sudden-onset severe headache. Computed tomography revealed diffuse hemorrhage in the subarachnoid space, and angiography revealed an aneurysm at the distal middle cerebral artery. Superficial temporal artery-middle cerebral artery bypass, aneurysmal trapping, and aneurysm resection were performed within 24 hours of admission. Staining for AE1/AE3 revealed accumulation of atypical cells with a high nuclear-cytoplasmic ratio in the aneurysmal wall. After showing initial improvement, she developed disturbed consciousness due to complicated ventricular enlargement on day 45. Although the cerebrospinal fluid in the acute phase had no atypical cells, subsequent testing revealed atypical cells, which supported a diagnosis of leptomeningeal carcinomatosis due to breast cancer dissemination. The patient died on day 78 after receiving standard endocrine therapy and radiation therapy. CONCLUSIONS: Tumor cells reach the leptomeninges via hematogenous spread or direct extension from preexisting lesions and can undergo neuraxis dissemination via the cerebrospinal fluid. Subarachnoid hemorrhage and leptomeningeal carcinomatosis are both devastating conditions with extremely poor prognoses. This patient experienced delayed disturbed consciousness leptomeningeal carcinomatosis with decreased performance status, which made it difficult to justify aggressive treatment on the basis of her poor prognosis.