Distinguishing Cerebral Infarction With Neck Pain and Hemiparesis From Cervical Spinal Epidural Hematoma Without MRI: A Case Report.

In patients presenting neck pain and hemiparesis, differentiation between cerebral infarction and cervical spinal epidural hematoma is vital yet challenging, particularly when magnetic resonance imaging (MRI) is not feasible. A 59-year-old woman presented with a sudden onset of left-sided hemiparesis and neck pain. MRI was contraindicated because the patient underwent embolization in childhood. Head computed tomography (CT) revealed no evidence of hemorrhage or early ischemic signs. Cervical CT revealed no evidence of hematoma within the spinal canal. Myelography and CT myelography revealed no significant cervical spine abnormalities. The diagnosis was cerebral infarction. Cervical spine MRI is the gold standard examination for diagnosing cervical spinal epidural hematoma, but cervical spine CT, myelography, and CT myelography may be useful when MRI is contraindicated.

Usefulness of non-slip element percutaneous transluminal angioplasty scoring balloons in treating severe calcified lesions of the carotid artery for carotid artery stenting: A case report.

Background: Treatment of calcified lesions with conventional angioplasty balloons can be difficult due to insufficient lumen expansion, high dissection rates, and repeated revascularization. We report a case in which a scoring balloon was used in lesions resistant to angioplasty with a semi-compliant balloon. Case Description: A 72-year-old man presented with severe stenosis and a highly calcified lesion in the right cervical internal carotid artery. Right carotid artery stenting (CAS) was planned to prevent future ischemic stroke events. Conventional semi-compliant balloon angioplasty was unsuccessful. Three inflations of a non-slip element (NSE) percutaneous transluminal angioplasty (PTA) scoring balloon (Nipro, Osaka, Japan) successfully achieved CAS without complications. Conclusion: This is the first report to describe the use of this scoring balloon in de novo carotid artery disease. NSE PTA scoring balloon catheters can be a useful option for refractory, highly calcified stenosis.

Hands-on neuroendovascular practice for nonselective undergraduate medical students increases interest and aspirations in pursuing neurosurgery as a specialization.

Background: The number of medical students aspiring to become neurosurgeons has decreased worldwide, mainly due to poor work-life balance among neurosurgeons; therefore, recruiting students for neurosurgery is essential to ensure the availability and appropriate quality of neurosurgical treatment. This study aimed to evaluate the efficacy of hands-on neuroendovascular practice for nonselective undergraduate medical students to determine whether this increases their interest in neurosurgery and contributes to their aspirations of becoming neurosurgeons. Methods: Hands-on neuroendovascular practice for mechanical thrombectomy was performed by undergraduate 5th-year medical students during their 2-week clinical rotation in the Department of neurosurgery at our university hospital between April 2021 and March 2023. After the neurosurgery practice, a questionnaire about their understanding of neurosurgery and aspirations for this specialization before and after the practice was anonymously completed by all students. Results: Overall, 153 students completed the questionnaire. Of these, 140 (91.5 %) showed increased interest in neurosurgery after participating in the hands-on practice. Through this practice, the number of students who considered neurosurgery as their first choice or one of their specialty choices increased from 8 (5.2%) to 12 (7.8%) (P = 0.3534) and from 19 (12.4%) to 52 (34.0%) (P < 0.0001), respectively. Furthermore, the number of students with no aspiration to become neurosurgeons decreased from 95 (62.1%) to 43 (28.1%) (P < 0.0001). Conclusion: Hands-on neuroendovascular practice for nonselective undergraduate medical students effectively increased their interest in neurosurgery specialization and their desire to become neurosurgeons. Therefore, this practice can help recruit medical students for neurosurgery specialization.

[Initial Clinical Experience with Dynamic C-arm CT Perfusion Acquisitions].

PURPOSE: Dynamic C-arm computed tomography perfusion (C-arm CTP) is a newly developed application that can provide cerebral perfusion images in the angio suite, similar to conventional multi-detector CTP in a diagnostic room. We introduce the workflow of C-arm CTP acquisition and our initial experience in a clinical setting. METHOD: C-arm CTP was acquired with 40 ml of non-diluted contrast medium injected at 4 ml/s in the median cubital vein followed by 30 ml of saline injected at the same rate. The injection began 5 seconds after the acquisition was started. Two mask runs were followed with eight successive fill runs. Arterial input function was automatically calculated to deliver perfusion maps. Incidence of acquisition errors was evaluated in two phases. RESULT: C-arm CTP images were successfully acquired in all cases, and the images provided useful information under a stable examination protocol. However, we experienced some operational and systematic artifacts that degraded image quality of perfusion maps in Phase 1. The incident rate of errors was significantly improved in Phase 2. CONCLUSION: C-arm CTP acquisitions were feasible during acute stroke treatment in the angio suite. It is expected that the image quality will be further improved through process improvement and reconstruction setting optimization to minimize unexpected artifacts in individual cases.

Evaluation of Cerebral Hyperperfusion After Carotid Artery Stenting Using C­Arm CT Measurements of Cerebral Blood Volume.

PURPOSE: Hyperperfusion syndrome (HPS) after carotid artery stenting (CAS) causes serious symptoms; therefore, early evaluation after CAS is considered to be important. Measurement of cerebral blood volume using C­arm computed tomography (C-arm CBV) has recently become possible. Here, the usefulness of C­arm CBV for the evaluation of hyperperfusion was investigated. METHODS: C-arm CBV was measured before and immediately after CAS in 30 patients. The regions of interest (ROI) were set in the bilateral middle cerebral artery perfused regions, and the affected/healthy side ratio of measured C­arm CBV (CBV ratios) was determined to evaluate cerebral perfusion. For comparing values before and after CAS, the CBV ratio increase rate (postoperative CBV ratios/preoperative CBV ratios) was also determined. RESULTS: C-arm CBV was successfully measured in 30 patients. Intracerebral hemorrhage (ICH) was detected in 3 patients, and no other patient had hyperperfusion syndrome. In the patients who developed ICH, postoperative C­arm CBV on the affected side was high, and a marked increase was confirmed in the postoperative CBV ratios. Postoperative CBV ratios were 1.03 ± 0.40 and 1.45 ± 0.68 in the non-ICH and ICH groups, and CBV ratio increase rates were 2.7 ± 24.0% and 28.5 ± 26.7% in the non-ICH and ICH groups, respectively; these differences were statistically significant (P < 0.01). CONCLUSION: C-arm CT allows CBV measurements immediately after CAS without requiring transport of the patient out of the angiography room, and it may enable the evaluation of hyperperfusion before and after CAS.

[Effect of magnetic fields from home-use magnetic induction therapy apparatuses on adjustable cerebrospinal fluid shunt valves].

OBJECTIVE: Cerebrospinal fluid (CSF) shunts are frequently used to treat hydrocephalus. The use of a programmable valve allows the operator to easily change the opening pressure. In Japan, many people use magnetic induction therapy apparatuses in their homes. However, exposing patients with adjustable CSF shunt valves to the permanent magnets included in these apparatuses may alter the shunt valve's programmed settings or permanently damage the device. Therefore, the goal of this study was to determine the health risk associated with magnetic induction therapy for patients using programmable CSF shunt valves. METHODS: Five models of shunt valves from five different manufacturers, the Miethke proGAV (proGAV), the Codman Hakim programmable valve (CHPV), Sophysa Sophy model SM8 (Sophy valve), Sophysa Polaris model SPV (Polaris valve), and Strata II valve (Strata valve) were evaluated in this study. Magnetic field interactions were determined for the programmable valves by using magnetic stones with various magnetic flux densities. The maximum distance between the valve and the magnetic stone affecting the valve pressure setting was measured by X-ray. RESULTS: The proGAV and Polaris valve were immune to unintentional reprogramming by the magnetic stones. The CHPV, Sophy valve and Strata valve, however, randomly changed settings by magnetic stones. CONCLUSIONS: Whereas the CHPV, Sophy valve and Strata valve were promptly reset by exposure to a magnetic stone with a similar strength to that used in magnetic induction therapy, proGAV and Polaris valve were resistant to inadvertent reprogramming when exposed to magnets up to 190 mT.

[Case of reversible posterior leukoencephalopathy syndrome after discontinuation of antihypertensive therapy].

A 36-year-old man who was poorly compliant with his antihypertensive medication regimen was admitted to our hospital because he had nausea and an altered mental status. His disorientation increased on admission. His blood pressure was 219/156 mmHg. No focal neurologic deficits were detected, but a cranial computed tomography (CT) performed on admission revealed a low-density area in the brainstem region. Subsequent cranial T2-weighted and fluid-attenuated inversion-recovery (FLAIR) magnetic resonance imaging (MRI) performed on the same day revealed high-intensity areas in the brainstem, bilateral cerebellar hemisphere, bilateral occipito-temporal subcortical white matter, right thalamus, and the right basal ganglia region. Diffusion-weighted MRI revealed that the edema was of vasogenic origin and was not indicative of ischemia/infarction. Biochemical testing revealed a blood urea nitrogen level of 35.7 mg/dL, a serum creatinine level of 3.27 mg/dL, proteinurea (4.6 g/24 hours), and a glomerular filtration rate of 47. 6 mL/min/1.83 m2. These findings suggested a diagnosis of chronic kidney disease (CKD). The patient was diagnosed with hypertensive encephalopathy, and treatment with intravenous diltiazem was initiated. The clinical symptoms resolved 3 days after admission, and the abnormal findings in CT and MRI demonstrated completely resolved 44 days after admission. This was a rare case of reversible posterior leukoencephalopathy syndrome (RPLS) that was caused by severe hypertension and was aggravated by discontinuation of antihypertensive therapy. RPLS was caused by vasogenic edema because of sudden elevations in systemic blood pressure which exceed the autoregulatory capacity of the brain vasculature.

[Efficacy of preoperative radiation therapy in hyper-vascular solitary fibrous tumor].

The hyper-vascular form of solitary fibrous tumors (SFTs) is rare and there have been few therapeutic evaluations of this entity. We encountered a hyper-vascular SFT and had difficulty removing it surgically. Following radiotherapy, both tumor size and feeder vessels were reduced and we could proceed with gross total removal. A 29-year-old woman was admitted with a 1-year history of decreasing visual acuity on the right side. Magnetic resonance imaging with gadolinium enhancement showed a homogenous enhancing mass (6x5x5 cm) which expanded the superior and inferior tentorium cerebelli. The tumor was fed by the left posterior cerebral artery, bilateral middle meningeal arteries and the right occipital artery. The first operation employed an occipital transtentorial approach and a highly vascular tumor was found. Tumor resection was limited due to severe bleeding. Histologically, the tumor showed focal hypercellularity with spindle cells and numerous capillaries. Immunohistochemically, the tumor was diffusely positive for CD34 and a diagnosis of SFT, hyper-vascular subtype, was made. After the first operation, local irradiation of a total of 40 Gy was performed. Both the tumor size and vascularity decreased dramatically. At the second operation, gross total removal was able to be performed. Radiotherapy appears effective in reducing the hyper-vascular subtype of SFT and would be one possible therapy to deal with these tumors, given their propensity of excessive bleeding during initial surgery.

Effect of linezolid against postneurosurgical meningitis caused by methicillin-resistant Staphylococcus epidermidis: case report.

A 67-year-old man who had twice previously undergone operations for a tuberculum sellae meningioma was admitted to hospital for further treatment. After the third surgical intervention, the patient developed persistent low-grade fever and impaired consciousness. Computed tomography, 1 week after surgery, showed postsurgical hydrocephalus. Cerebrospinal fluid (CSF) studies revealed high intracranial pressure (above 30 cm H2O), and increased cell count (1232/3). One week after the ventricular drainage, coagulase-negative Staphylococcus epidermidis was recovered from his CSF, and antimicrobial susceptibility results indicated that the organism was methicillin-resistant. After 14 days of intravenous vancomycin (VCM) administration failed, linezolid (LZD) was initialized intravenously, resulting in a resolution of the meningitis. After a ventriculoperitoneal shunt procedure was performed, LZD was continued orally, which resulted in a cure. CSF penetration by VCM is reported to be poor, i.e., approximately 10% of serum concentration, which may explain its lack of efficacy. In this case, the penetration of LZD into the CSF was 58.9% of the peak value and 133% of the trough value of serum concentrations. LZD must be considered one of the first-line treatments against surgical-site infection in neurosurgery caused by methicillin-resistant Staphylococci.

[The influence on the images of computed tomography caused by the use of artificial cranial reconstructive materials].

Various materials have been used for cranioplasty; however, these materials frequently produce artifacts that appear when examined with conventional radiography. Computed tomography (CT), in particular, detects high density artifacts near artificial bones, which is manipulated by increased noise, and limits diagnostic performance. The purpose of this study was to evaluate the extent and shape of the artifacts due to artificial cranial bones and to consider CT imaging parameters necessary for accurate recognition of structures under the materials. Four different artificial bone materials were evaluated in this study: hydroxyapatite with 1) 40% or 2) 50% porosity, 3) titanium plate, and 4) hydroxyapatite-polymethylmethacrylate composite (HA-PMMA). CT scanning was performed with standard clinical settings. Sample specimens were placed on the right side, under the artificial bones, and CT was performed to evaluate specimen visibility. We compared the artifacts created by the four bone types listed above, and measured the CT values of those materials. With ordinary scan settings, all the artificial bones revealed high-density artifact surrounding the materials, including the inability to accurately measure specimen thickness. The upper part of the specimen in contact with the artificial bones could not be distinguished from the artifact. The CT value in the medial aspect of the artificial bones increased more than the actual CT values. Of the four artificial bone materials studied, HA-PMMA produced the fewest artifacts. Description of the structures under the artificial bones can be improved by extending the window width to approximately twice that of normal settings.

A 12 month in vivo study on the response of bone to a hydroxyapatite-polymethylmethacrylate cranioplasty composite.

We investigated the osteoconductivity and biocompatibility in vivo of a new hydroxyapatite-polymethylmethacrylate (HA-PMMA) composite developed for use as an implant material for cranioplasty, which is expected to have the good osteoconductivity of HA together with the strength and ease of handling of PMMA. The HA-PMMA composites were implanted in eight full-grown beagles and then 6, 12, 24 weeks and 1 year after implantation, the animals were sacrificed and the implanted materials removed along with the surrounding tissues. Extirpated specimens were studied using an optical microscope and micro-computed tomography (micro-CT). Fibrous connective tissue was prominent in the interface of the composite at 6 weeks. New bone formation was seen around the implant, 12 and 24 weeks after operation. At 1 year, new bone filled in the interface of the HA-PMMA composite and adhered to the surrounding autogenous bone. Mixing HA and PMMA did not interfere with the osteoconductivity of the HA component. In micro-CT findings, the new bone growing on the HA-PMMA composite could be seen attaching preferentially to HA particles exposed at the composite surface, rather than the PMMA. This study demonstrated that this HA-PMMA composite is a good candidate for cranial bone implants due to its good osteoconductivity and biocompatibility.

Conspicuous endoscopic appearance of ventriculitis caused by coagulase-negative staphylococci.

To date, reports about the macroscopic appearance of ventriculitis have been rare, consisting only of a few autopsy cases. A patient in our hospital had ventriculitis caused by coagulase-negative staphylococci, and under neuroendoscopy we obtained clear findings of granular ependymitis. A 44-year-old man was admitted for disturbance of consciousness caused by progressive hydrocephalus. He had experienced subarachnoid hemorrhage (SAH) from a left vertebral dissecting aneurysm, and had subsequently received a ventriculoperitoneal shunt against post-SAH hydrocephalus. After admission, he was found to have retrograde shunt infection from peritonitis caused by cholecystitis. Coagulase-negative staphylococci were detected in cerebrospinal fluid (CSF), and the infection persisted even with intrathecal administration of gentamycin, and intravenous administration of vancomycin and arbekacin. Endoscopic rinsing was performed, and multiple small yellowish microgranulations, less than 1 mm in diameter, were observed in the lateral ventricles and the third ventricle. Rinsing of the CSF after intensive antimicrobial treatment resulted in a cure. Because there have been no reports of endoscopic observations of bacterial ventriculitis, we were unable to be certain about the origin or significance of the microgranulations. However, whether or not the microgranulations were bacterial colonies, infection did not recur during a 2-year follow-up period.

[Spontaneous closure of dural arteriovenous fistula after performing diagnostic angiography].

The pathogenesis and clinical treatment of dural arteriovenous fistulas (DAVF) has been well established. However, only 15 cases of spontaneous closure of DAVFs have been reported. We describe a case of spontaneous closure of a DAVF. A 60-year-old male presented with pulsatile tinnitus. Selective cerebral angiography revealed a left posterior DAVF fed by the left occipital artery and the middle meningeal artery, which drained into the left transverse sinus and sigmoid sinus. Following the initial angiography, the patient exhibited vomiting with transient disorientation and amnesia. These symptoms, along with the tinnitus, disappeared by the following day. Seven days after the initial angiography, a second angiography was performed that revealed the complete disappearance of the DAVF. Previous reports have described a long period of closure for DAVFs following initial diagnosis. Possible mechanisms for spontaneous closure of DAVFs include the development of scar tissue or a sinus thrombosis that leads to occlusion of the DAVF In this case, the DAVF closure may have been due to a sinus thrombosis induced by sinus stenosis, since occlusion of the draining sinuses coincided with the spontaneous closure of the DAVF. In cases of non-traumatic DAVF without cortical venous reflex that do not present severe symptoms, a prudent course of treatment is necessary since there is a chance of spontaneous closure of the DAVF occuring.

[Evaluation of cerebral blood perfusion with IVR-CT/angio system during interventional procedures].

An interventional-radiology computed-tomography (IVR-CT)/angio system is a combination of an angiographic unit and a CT scanner. This system allows patient's movement in and out of the two imaging units, on the same table. Since June 2003, we have applied our conventional protocol for evaluation of cerebral blood perfusion during interventional radiology (IVR) procedures. We reviewed our experience using the IVR-CT/angio system and investigated the efficacy and limitations of this technique. No complications relating to radiation exposure, contrast medium use, or IVR procedures were observed. CT perfusion was useful for detecting cerebral perfusion impairment during IVR procedures. This was helpful in deciding the postoperative management. Because patients do not need to be transported to another radiographic suite to evaluate cerebral blood perfusion, the IVR-CT/angio system is ideal for safely and simply detecting cerebral perfusion defects during IVR procedures. However, it is important to consider whether there is sufficient indication for the procedure, because radiation exposure and the amount of contrast medium use are increased if the IVR procedures become difficult.

Dural invasion of meningioma: a histological and immunohistochemical study.

Meningioma usually grows and expands into the brain, but invasion into the brain parenchyma is relatively rare. Meningioma arises from arachnoid cap cells, and infiltration into dura mater is the main growth pattern of meningiomas. However, little is known about the mechanism of meningioma invasion into the dura mater. In this study, seven specimens, including dural attachments, from seven cases of meningioma were used for immunohistochemical analysis. Matrix metalloproteinase (MMP)-1, -2, -9, urokinase-type plasminogen activator (uPA), vascular endothelial growth factors (VEGF), flt-1, E-cadherin, estrogen receptor (EgR), progesterone receptor (PgR), and aquaporin (AQP)-1, -4 were used as primary antibodies. There were several patterns of meningioma invasion into the dura mater: papillary-shaped invasion with destruction of dural structure, infiltration along the fibers of the dura mater, and invasion of several tumor cell units with fibroblast infiltration. Strong immunostaining was obtained with MMP-1, followed by AQP-1 and uPA, within the invading tumor cells. Neovasculature and extravasated erythrocytes, which stained with AQP-1, were also occasionally observed around the invading tumor cells. Simpson grade II removal of meningiomas results in high recurrence rates, and the inhibition of meningioma growth via dural invasion will facilitate improved remission in many cases with meningioma. In this study, MMP-1, AQP-1, and uPA are considered to have some role in the dural infiltration of meningioma cells. The fact that AQP-1 was highly expressed at the dural attachment and invading front of meningioma may indicate that dural invasion of the meningioma may be facilitated by AQP-1-induced water flow and neovascularization.

Transcranial echo-guided transsphenoidal surgical approach for the removal of large macroadenomas.

OBJECT: Transsphenoidal surgery for the removal of macroadenomas has some disadvantages, including the risk of performing procedures without adequate visualization, difficulties in estimating the amount of residual tumor, and the risk of injuring major vessels. To overcome these disadvantages, the authors have developed transcranial echo-guided transsphenoidal surgery. METHODS: Three patients with large macroadenomas and two patients with irregularly shaped macroadenomas were selected for this operation. In addition to standard preparations for transsphenoidal surgery, in each case the right frontal bone was trephined and an echo probe was inserted transdurally through the trephination hole. During tumor removal, brightness-mode echo images and Doppler color flow images were obtained. The echo images allowed for real-time visualization of the tumor and surrounding brain structures including major arteries and the cisterns; histological heterogeneities of the tumor could also be appreciated. The tumors were removed safely and maximal tumor removal was achieved. CONCLUSIONS: Transcranial echo-guided transsphenoidal surgery provides real-time visualization of tumor removal. The method enhances the safety of this surgery, maximizes the removal of the tumor, and is inexpensive.

A case of prolactin-secreting pituitary carcinoma and its histological findings.

Pituitary carcinomas are very rare. The diagnosis of pituitary carcinoma is defined by evidence of craniospinal and/or systemic metastasis, rather than by histological malignancies. We report a case of prolactin-secreting pituitary macroadenoma invading the cavernous sinuses at the time of initial treatment, which later metastasized to the cerebellum, medulla oblongata, and spinal axis. The patient survived approximately nine years following the initial diagnosis of a pituitary tumor and two years following the diagnosis of metastatic disease. Histological examination of the metastatic cerebellar tumor showed an adenoma with high cellularity and hyperchromasia, but no mitoses.