Enlarging neurenteric cyst at the craniocervical junction with a fluid-fluid level on magnetic resonance imaging: illustrative case.

BACKGROUND: Neurenteric cysts are relatively rare benign congenital intracranial cystic lesions that enlarge rarely and very slowly. The authors present a case of an enlarging neurenteric cyst at the craniocervical junction with a fluid-fluid level on magnetic resonance imaging (MRI). OBSERVATIONS: A 34-year-old man with no significant medical history underwent head MRI to investigate mild headaches. An incidental cystic lesion, approximately 8 mm in diameter, was revealed at the craniocervical junction. Serial follow-up MRI showed cyst enlargement with a fluid-fluid level. Four years later, the cyst reached a size of 15 mm and was surgically removed. The cyst contained cloudy fluid with a high protein concentration, without any bleeding or tissue fragments. Pathological examination confirmed the diagnosis of a neurenteric cyst. The patient recovered well, was discharged home, and has remained recurrence free for 2 years. LESSONS: The growth dynamics of the relatively rapidly expanding neurenteric cyst at the craniocervical junction were monitored over time using MRI. This cyst exhibited the distinctive feature of a fluid-fluid level as it enlarged. Investigating the mechanisms underlying fluid-fluid level formation may offer novel insights into the pathogenesis of cyst enlargement. https://thejns.org/doi/10.3171/CASE24180.

Significance of upper cervical epidural venous engorgement on head computed tomography in the initial diagnosis of spontaneous intracranial hypotension: patient series.

BACKGROUND: Spontaneous intracranial hypotension (SIH) is a rare condition characterized by positional headache, for which contrast-enhanced magnetic resonance imaging (MRI) is the preferred diagnostic method. Although MRI reveals characteristic findings, head computed tomography (CT) is usually the first diagnostic step, but identifying features of SIH on CT is often difficult. This study was specifically designed to evaluate the utility of head CT in detecting upper cervical epidural venous engorgement as a sign of SIH. OBSERVATIONS: Of 24 patients with SIH diagnosed between March 2011 and May 2023, 10 did not undergo upper cervical CT. In the remaining 14 patients, engorgement of the upper cervical epidural venous plexus was observed. CT detection rates were consistent with MRI for spinal fluid accumulation or dural thickening. After treatment, in 92.9% of patients, the thickness of the epidural venous plexus decreased statistically significantly from 4.8 ± 1.3 mm to 3.6 ± 1.2 mm. LESSONS: This study suggests that upper cervical spine CT focused on epidural venous engorgement may be helpful in the initial diagnosis of SIH and may complement conventional MRI evaluation. Extending CT imaging to the upper cervical spine will improve the diagnostic accuracy of patients with positional headaches suspected to be SIH.

Hidden Bow Hunter's Syndrome Diagnosed Using Dynamic Cerebral Angiography and Successfully Treated with Spinal Surgery: A Case Report and Review of the Literature.

Hidden bow hunter's syndrome (HBHS) is a rare disease in which the vertebral artery (VA) occludes in a neutral position but recanalizes in a particular neck position. We herein report an HBHS case and assess its characteristics through a literature review. A 69-year-old man had repeated posterior-circulation infarcts with right VA occlusion. Cerebral angiography showed that the right VA was recanalized only with neck tilt. Decompression of the VA successfully prevented stroke recurrence. HBHS should be considered in patients with posterior circulation infarction with an occluded VA at its lower vertebral level. Diagnosing this syndrome correctly is important for preventing stroke recurrence.

Endovascular Embolization with n-Butyl Cyanoacrylate for Ruptured Distal Posterior Inferior Cerebellar Artery Dissecting Aneurysm.

Parent artery occlusion is a definitive treatment method for preventing rebleeding of dissecting aneurysms. We herein report a case of a ruptured distal posterior inferior cerebellar artery (PICA) dissecting aneurysm treated with internal trapping using n-butyl-2-cyanoacrylate (NBCA). A 65-year-old man visited our hospital with a complaint of headache and neck pain that began 1 week before his arrival. He had a history of spontaneous subarachnoid hemorrhage of unknown cause. Computed tomography of the brain revealed a small amount of subarachnoid hemorrhage, and distal subtraction angiogram showed a distal PICA dissecting aneurysm. We placed a guiding catheter in the left vertebral artery and an intermediate catheter in the PICA. A microcatheter was guided toward the proximal side of the aneurysm and was wedged into the parent artery. The dissecting aneurysm was treated with parent artery occlusion using 50% NBCA. The postoperative course was uneventful, and the patient was discharged 3 weeks after treatment without any neurological deficit. Parent artery occlusion with internal trapping using NBCA could be a safe and definitive treatment method for distal PICA dissecting aneurysms. Angiographical evaluation of the collateral network in the distal branch of PICA before embolization and wedged microcatheter technique in the parent artery are important for successful embolization using NBCA.

Traumatic dissection of the anterior cerebral artery secondary to a rugby related impact: A case report with emphasis on the usefulness of T1-VISTA.

Background: Cerebrovascular injuries (CVIs) are not usually considered in the differential diagnosis of sport-related head injuries (SRHIs). We encountered a rugby player with traumatic dissection of the anterior cerebral artery (ACA) after impact on the forehead. Head magnetic resonance imaging (MRI) with T1-volume isotropic turbo spin-echo acquisition (VISTA) was used to diagnose the patient. Case Description: The patient was a 21-year-old man. During a rugby tackle, his forehead collided with the forehead of an opponent. He did not have a headache or disturbance of consciousness immediately after the SRHI. On the 2nd day of illness, he had transient weakness of the left lower limb several times. On the 3rd day of illness, he visited our hospital. MRI revealed occlusion of the right ACA and acute infarction of the right medial frontal lobe. T1-VISTA revealed intramural hematoma of the occluded artery. He was diagnosed with acute cerebral infarction due to dissection of the ACA and was followed up for vascular changes with T1-VISTA. The vessel had recanalized and the size of the intramural hematoma had decreased 1 and 3 months after the SRHI, respectively. Conclusion: Accurate detection of morphological changes in cerebral arteries is important for the diagnosis of intracranial vascular injuries. When paralysis or sensory deficits occur after SRHIs, it is difficult to differentiate between concussion from CVI. Athletes with red-flag symptoms after SRHIs should not merely be suspected to have concussion; they should be considered for imaging studies.

Carotid artery stenosis concomitant with severe aortic stenosis treated by combination of staged angioplasty and transcatheter aortic valve implantation: A case report.

Background: When severe aortic stenosis (AS) is concomitant with carotid stenosis, carotid artery stenting (CAS) will become a high-risk procedure because baroreceptor reflex-induced bradycardia and hypotension may cause irreversible circulatory collapse. When carotid stenosis-related misery perfusion is present, the risk of cerebral hyperperfusion syndrome increases after carotid revascularization. We report a case of severe carotid disease concomitant with severe AS successfully treated by a combination of staged angioplasty (SAP) and transcatheter aortic valve implantation (TAVI). Case Description: An 86-year-old man presented with transient deterioration of mental status and sluggish responsiveness continuous from the previous day. Magnetic resonance imaging of the brain revealed a right putaminal infarction, occlusion of the right internal carotid artery (ICA), and severe stenosis of the left ICA. Severe AS was diagnosed and single-photon emission computed tomography showed misery perfusion at the bilateral ICA territories. We performed a staged treatment consisting of SAP for the left carotid stenosis and TAVI. A first-stage carotid angioplasty was performed, followed by TAVI 2 weeks later and second-stage CAS 1 week after that. There were no apparent periprocedural complications throughout the clinical course. Conclusion: Combining SAP and TAVI may be an effective treatment option for severe carotid stenosis with misery perfusion concomitant with severe AS.

Emergent carotid artery stenting for cervical internal carotid artery injury during carotid endarterectomy: A case report.

BACKGROUND: Carotid endarterectomy (CEA) has been the standard preventive procedure for cerebral infarction due to cervical internal carotid artery stenosis, and internal shunt insertion during CEA is widely accepted. However, troubleshooting knowledge is essential because potentially life-threatening complications can occur. Herein, we report a case of cervical internal carotid artery injury caused by the insertion of a shunt device during CEA. CASE DESCRIPTION: A 78-year-old man with a history of hypertension, diabetes, and hyperuricemia developed temporary left hemiplegia. A former physician had diagnosed the patient with a transient cerebral ischemic attack. The patient's medical history was significant for the right internal carotid artery stenosis, which was severe due to a vulnerable plaque. We performed CEA to remove the plaque; however, there was active bleeding in the distal carotid artery of the cervical region after we removed the shunt tube. Hemostasis was achieved through compression using a cotton piece. Intraoperative digital subtraction angiography (DSA) revealed severe stenosis at the internal carotid artery distal to the injury site due to hematoma compression. The patient underwent urgent carotid artery stenting and had two carotid artery stents superimposed on the injury site. On DSA, extravascular pooling of contrast media decreased on postoperative day (POD) 1 and then disappeared on POD 14. The patient was discharged home without sequela on POD 21. CONCLUSION: In the case of cervical internal carotid artery injury during CEA, hemostasis can be achieved by superimposing a carotid artery stent on the injury site, which is considered an acceptable troubleshooting technique.

Antioxidant nanomedicine with cytoplasmic distribution in neuronal cells shows superior neurovascular protection properties.

This study investigated whether nitroxide radical (4-amino-TEMPOL)-containing nanoparticles (RNPs; antioxidant nanomedicine) can prevent neurovascular unit impairment caused by reactive oxygen species (ROS) after cerebral ischemia-reperfusion. C57BL/6J mice underwent transient middle cerebral artery occlusion (tMCAO). The mice were randomly divided and administered intra-arterial RNPs injection (9 mg/kg, 7 µM/kg), edaravone (3 mg/kg, 17 µM/kg), or phosphate-buffered saline (control group). Survival rate and neurological score were evaluated 24 h post-injection. RNPs distribution was determined using immunofluorescence staining and blood-brain barrier (BBB) disruption using Evans blue extravasation assay. Effect of RNPs and edaravone on microglia polarization into microglia M1 and M2 was evaluated. We also determined multiple ROS-scavenging activities in brain homogenates of RNPs- and edaravone-treated animals using an electron spin resonance-based spin-trapping method. Compared with edaravone, RNPs significantly improved the survival rate and neurological deficit, inhibited BBB disruption and supported polarization of microglia into M2 microglia. RNPs were localized in endothelial cells, the perivascular space, neuronal cell cytoplasm, astrocytes, and microglia. Scavenging capacities of hydroxyl, alkoxyl, and peroxyl radicals were significantly higher in the RNPs-treated group. RNPs show promising results as a future neuroprotective nanomedicine approach for cerebral ischemia-reperfusion injury.

Correlation Between Bone Density and Lumbar Compression Fractures.

Objectives: Bone densitometry is widely used to evaluate osteoporosis; however, it is pointed out that bone density may be high in the case of fractures, deformities, and osteosclerotic changes. The present study evaluated bone density measured at our hospital and evaluated its correlation with the presence or absence of lumbar spine fractures. Methods: Bone density of the lumbar spine and femur was measured in 185 patients from July 2017 to June 2019 at our hospital, and the presence or absence of a lumbar spine compression fracture was evaluated on the basis of the image. Information regarding age, sex, lumbar bone density, presence or absence of lumbar fracture, number of lumbar fractures, and grade of lumbar fracture was also statistically evaluated. Results: Analysis was performed for 185 patients (20 males and 165 females, average age 76.9 ± 7.5 years). The bone density was 0.830 ± 0.229 of compression fractured bodies (number of vertebral bodies were 132) and 0.765 ± 0.178 g/cm3 of noncompression fractured bodies (number of vertebral bodies was 608). Discussion: The presence of lumbar fractures significantly increases bone density. For diagnosing osteoporosis, both bone density and the possibility of lumbar spine fractures must be considered.

Novel neuroprotection using antioxidant nanoparticles in a mouse model of head trauma.

INTRODUCTION: Free radicals and reactive oxygen species are related to deteriorating pathological conditions after head trauma because of their secondary effects. 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO) scavenges free radicals; however, this molecule is also toxic. Here, we have evaluated the neuroprotective effect of antioxidant nanoparticles, which consisted of a novel core-shell type nanoparticle containing 4-amino-TEMPO, that is, redox-active nitroxide radical-containing nanoparticles (RNPs). METHODS: Institute of Cancer Research mice were subjected to a head-impact procedure, randomly divided into four groups and intravenously (3 mg/kg) administered phosphate-buffered saline, TEMPO, micelle (a self-assembling block copolymer micelle without a TEMPO moiety), or RNP through the tail vein immediately thereafter and intraperitoneally at days 1, 3, and 5 after traumatic brain injury (TBI). The RNP distribution was detected by rhodamine labeling. Cognitive behavior was assessed using the neurological severity score and a rotarod test at days 1, 3, and 7 following TBI, and contusion volume was measured at day 7 after TBI. Free radical-scavenging capacity was analyzed by electron paramagnetic resonance on day 1 after TBI, and immunostaining was used to observe mobilization of microglia (Iba-1) and rescued neuronal cells (NeuN). RESULTS: Redox-active nitroxide radical-containing nanoparticle was detected in the microvessels around the injured area in the brain. Cognitive behavior assessment was significantly better, and contusion volume was significantly smaller in the RNP group compared with the other groups. Superoxide anion scavenging capacity was significantly higher in the RNP group, and neuronal loss was significantly suppressed around the injured area at day 7 after TBI. Furthermore, in the RNP group, neurodegenerative microglia production was suppressed at days 3 and 7 after TBI, whereas neuroprotective microglia production was higher at day 7 after TBI. CONCLUSION: The RNP administration after TBI improved cognitive behavior and reduced contusion volume by improving reactive oxygen species scavenging capacity. Therefore, RNP may have a neuroprotective effect after TBI. LEVEL OF EVIDENCE: Therapeutic test.

[A Case of a Ruptured Cerebral Aneurysm Associated with Microscopic Polyangiitis].

CASE: A 71-year-old woman was receiving dialysis for microscopic polyangiitis(MPA). She was transported to the emergency room after developing a headache and losing consciousness. She was in a coma and had dense left paralysis. Head computed tomography(CT)showed a subarachnoid hemorrhage. Head three-dimensional CT angiography showed an aneurysm proximal to the right M2(inferior trunk), which was considered as the source of bleeding. We performed an emergency aneurysm clipping surgery. However, we placed a permanent clip on the arterial wall defect when the clip detached from the parent artery. Pathological examination of the aneurysm revealed that the layered structure of the artery was damaged because of fibrin degeneration, suggesting that the aneurysm was caused by vasculitis. Coma persisted after surgery, and the patient was transferred to another hospital. DISCUSSION: We found only one report demonstrating an association between a cerebral aneurysm and MPA. Aneurysms resulting from vasculitis are common at the periphery, rather than at vessel bifurcations. Cyclic inflammatory activity causes progressive destruction of the blood vessel wall, further expanding the lumen and forming an aneurysm. Therefore, such aneurysms are more fragile than true aneurysms, and are more likely to be damaged or detached during surgery, as in the present case. Trapping of the parent artery should be considered when the aneurysm is damaged or detached. Accordingly, preoperative planning could anticipate the need for superficial temporal artery to middle cerebral artery bypass.

[Endoscopic Endonasal Transethmoidal Biopsy for IgG4-Related Intraorbital Pseudotumor:A Case Report].

BACKGROUND: We experienced a case of intraorbital pseudotumor associated with IgG4-related disease, for which we successfully performed an endoscopic endonasal transethmoidal biopsy for the intraorbital pseudotumor as well as endoscopic sinus surgery for a refractory pansinusitis at the same time. CASE REPORT: A 59-year-old man was referred to our hospital because of an intraorbital mass lesion. MRI showed 2 mass lesions:a large intraconal lesion encasing the left optic nerve on the orbital apex, and a small extraconal lesion medial to the left medial rectus muscle extending into the anterior ethmoid canal. In addition, CT showed severe pansinusitis. A blood test showed a marked elevation of IgG4. IgG4-related pseudotumor was suspected, but IgG4-related MALT lymphoma was an alternative diagnosis, and a biopsy of the mass lesion was required. We successfully performed both, an endoscopic endonasal transethmoidal biopsy for the mass lesion and endoscopic sinus surgery for the refractory pansinusitis at the same time. The pathological diagnosis was an IgG4-related pseudotumor. CONCLUSION: Endoscopic endonasal transethmoidal biopsy is an effective and minimally invasive method for making a definitive diagnosis of IgG4-related intraorbital pseudotumor. Using this method, refractory pansinusitis frequently associated with this disease can be treated. For successful treatment, interdisciplinary decision making and collaborative team surgery are crucial.

Using catheter needles to deliver an intraocular lens for intrascleral fixation.

UNLABELLED: A new method for delivering intraocular lens (IOL) haptics through sclerotomies for intrascleral fixation using catheter needles was evaluated in pig eyes. A bent catheter needle was used to penetrate the surgical corneal wound from the presumed sclerotomy. Extraocularly, the leading haptic of the IOL was fixated between the external tube and the internal needle of the catheter needle. The fixation was strong enough to support the IOL and to extract the leading haptic through the sclerotomy site. The trailing haptic was fixated using another catheter needle extraocularly and was subsequently delivered through another sclerotomy site. Guiding with a needle was the only intraocular manipulation when delivering the trailing haptic and catheter needle through the sclerotomy. This new method is easy and safe and does not require special devices compared with other methods. Clinical evaluation in human eyes should be performed. FINANCIAL DISCLOSURE: Dr. Akimoto is a consultant to Kowa Co. Ltd. A patent application on the modified catheter needle is planned. No other author has a financial or proprietary interest in any material or method mentioned.

Dual-port technique in navigation-guided endoscopic resection for intraparenchymal brain tumor.

BACKGROUND: In navigation-guided endoscopic surgery performed via a single port, the interference of surgical instruments often disturbs the resection and hemostasis. CASE DESCRIPTION: With regard to this, we designed a dual-port technique for navigation-guided endoscopic surgery in a 62-year-old man, with intraparenchymal anaplastic astrocytoma. Two transparent sheaths with Nelaton tubes were inserted in the front of the target lesion via an infinity-shaped burr hole, under the control of the navigation system. The lesion was removed partially using a rigid endoscope and several surgical tools through the bilateral ports. Using the new method, it was convenient to perform hemostasis with bipolar coagulation and aspiration, without any interference from the surgical instruments during the surgery. CONCLUSION: The offered dual-port technique may be included in surgery planning for elderly patients or patients in particular conditions, with intraparenchymal brain tumors.

Mixed germ cell tumor with extensive yolk sac tumor elements in the frontal lobe of an adult.

Intracranial nongerminomatous germ cell tumors (NGGCTs) in unusual locations are extremely rare. Here, we report a case of a yolk sac tumor in the frontal lobe in a middle-aged patient. A 42-year-old man was admitted to our hospital for headache and nausea. Magnetic resonance imaging (MRI) showed an enhanced mass lesion with a marked cyst component. The serum alpha-fetoprotein (αFP) level was extremely high. Histological examination of specimens after subtotal removal revealed a primary mixed germ cell tumor with extensive yolk sac tumor elements, often referred to as an intracranial "yolk sac tumor." The preoperative diagnosis of NGGCTs in unusual age and locations is extremely difficult. Clinicians should consider the possibility of NGGCTs, including yolk sac tumors, when intracranial tumors with unusual MRI findings are encountered.