Cranial and spinal computed tomography (CT) angiography with photon-counting detector CT: comparison with angiographic and operative findings.

The clinical imaging features of photon-counting detector (PCD) computed tomography (CT) are mainly known as dose reduction, improvement of spatial resolution, and reduction of artifacts compared to energy-integrating detector CT (EID-CT). The utility of cranial and spinal PCD-CT and PCD-CT angiography (CTA) has been previously reported. CTA is a widely used technique for noninvasive evaluation. Cranial CTA is important in brain tumors, especially glioblastoma; it evaluates whether the tumor is highly vascularized prior to an operation and helps in the diagnosis and assessment of bleeding risk. Spinal CTA has an important role in the estimation of feeders and drainers prior to selective angiography in the cases of spinal epidural arteriovenous fistulas and spinal tumors, especially in hemangioblastoma. So far, EID-CTA is commonly performed in an adjunctive role prior to selective angiography; PCD-CTA with high spatial resolution can be an alternative to selective angiography. In the cases of cerebral aneurysms, flow diverters are important tools for the treatment of intracranial aneurysms, and postoperative evaluation with cone beam CT with angiography using diluted contrast media is performed to evaluate stent adhesion and in-stent thrombosis. If CTA can replace selective angiography, it will be less invasive for the patient. In this review, we present representative cases with PCD-CT. We also show how well the cranial and spinal PCD-CTA approaches the accuracy of angiographic and intraoperative findings.

Cervical spinal cord stimulation exerts anti-epileptic effects in a rat model of epileptic seizure through the suppression of CCL2-mediated cascades.

Epidural spinal cord stimulation (SCS) is indicated for the treatment of intractable pain and is widely used in clinical practice. In previous basic research, the therapeutic effects of SCS have been demonstrated for epileptic seizure. However, the mechanism has not yet been elucidated. In this study, we investigated the therapeutic effect of SCS and the influence of epileptic seizure. First, SCS in the cervical spine was performed. The rats were divided into four groups: control group and treatment groups with SCS conducted at 2, 50, and 300 Hz frequency. Two days later, convulsions were induced by the intraperitoneal administration of kainic acid, followed by video monitoring to assess seizures. We also evaluated glial cells in the hippocampus by fluorescent immunostaining, electroencephalogram measurements, and inflammatory cytokines such as C-C motif chemokine ligand 2 (CCL2) by quantitative real-time polymerase chain reaction. Seizure frequency and the number of glial cells were significantly lower in the 300 Hz group than in the control group. SCS at 300 Hz decreased gene expression level of CCL2, which induces monocyte migration. SCS has anti-seizure effects by inhibiting CCL2-mediated cascades. The suppression of CCL2 and glial cells may be associated with the suppression of epileptic seizure.

[Initial Medical Care for Spinal Injury].

Neurosurgeons who treat head traumas often encounter cervical spinal injuries. They should be aware of the neurological symptoms, the severity of the symptoms, and the imaging features of cervical injuries. When surgery is required, fixation is often performed.

IDH-mutant Astrocytoma Arising in the Brainstem with Symptom Improvement by Foramen Magnum Decompression: A Case Report.

Diffusely infiltrative midline gliomas are known to have a poor prognosis. The standard treatment for typical diffuse midline glioma in the pons is local radiotherapy as surgical resection is inappropriate. This case reports a brainstem glioma in which stereotactic biopsy and foramen magnum decompression were concomitantly performed to confirm the diagnosis and improve symptoms. A 23-year-old woman was referred to our department with a chief complaint of headache for six months. Magnetic resonance imaging (MRI) showed diffuse T2 hyperintense swelling of the brainstem with the pons as the main locus. Enlargement of the lateral ventricles was observed because of cerebrospinal fluid obstruction out of the posterior fossa. This was atypical for a diffuse midline glioma in terms of the longstanding slow progression of symptoms and patient age. Stereotactic biopsy was performed for diagnosis, and foramen magnum decompression (FMD) was concomitantly performed to treat the obstructive hydrocephalus. The histological diagnosis was astrocytoma, IDH-mutant. Post-surgery, the patient's symptoms were relieved, and she was discharged on the fifth day after surgery. The hydrocephalus was resolved, and the patient returned to normal life without any symptoms. The tumor size follow-up with MRI demonstrated no marked change for 12 months. Even though diffuse midline glioma is considered to have a poor prognosis, clinicians should contemplate if it is atypical. In atypical cases like the one described herein, surgical treatment may contribute to pathological diagnosis and symptom improvement.

Continuous vagus nerve stimulation exerts beneficial effects on rats with experimentally induced Parkinson's disease: Evidence suggesting involvement of a vagal afferent pathway.

BACKGROUND: Vagus nerve stimulation (VNS) exerts neuroprotective and anti-inflammatory effects in preclinical models of central nervous system disorders, including Parkinson's disease (PD). VNS setting applied for experimental models is limited into single-time or intermittent short-duration stimulation. We developed a VNS device which could deliver continuous stimulation for rats. To date, the effects of vagal afferent- or efferent-selective stimulation on PD using continuous electrical stimulation remains to be determined. OBJECTIVE: To investigate the effects of continuous and selective stimulation of vagal afferent or efferent fiber on Parkinsonian rats. METHODS: Rats were divided into 5 group: intact VNS, afferent VNS (left VNS in the presence of left caudal vagotomy), efferent VNS (left VNS in the presence of left rostral vagotomy), sham, vagotomy. Rats underwent the implantation of cuff-electrode on left vagus nerve and 6-hydroxydopamine administration into the left striatum simultaneously. Electrical stimulation was delivered just after 6-OHDA administration and continued for 14 days. In afferent VNS and efferent VNS group, the vagus nerve was dissected at distal or proximal portion of cuff-electrode to imitate the selective stimulation of afferent or efferent vagal fiber respectively. RESULTS: Intact VNS and afferent VNS reduced the behavioral impairments in cylinder test and methamphetamine-induced rotation test, which were accompanied by reduced inflammatory glial cells in substantia nigra with the increased density of the rate limiting enzyme in locus coeruleus. In contrast, efferent VNS did not exert any therapeutic effects. CONCLUSION: Continuous VNS promoted neuroprotective and anti-inflammatory effect in experimental PD, highlighting the crucial role of the afferent vagal pathway in mediating these therapeutic outcomes.

Synergistic therapeutic effects of intracerebral transplantation of human modified bone marrow-derived stromal cells (SB623) and voluntary exercise with running wheel in a rat model of ischemic stroke.

BACKGROUND: Mesenchymal stromal cell (MSC) transplantation therapy is a promising therapy for stroke patients. In parallel, rehabilitation with physical exercise could ameliorate stroke-induced neurological impairment. In this study, we aimed to clarify whether combination therapy of intracerebral transplantation of human modified bone marrow-derived MSCs, SB623 cells, and voluntary exercise with running wheel (RW) could exert synergistic therapeutic effects on a rat model of ischemic stroke. METHODS: Wistar rats received right transient middle cerebral artery occlusion (MCAO). Voluntary exercise (Ex) groups were trained in a cage with RW from day 7 before MCAO. SB623 cells (4.0 × 105 cells/5 µl) were stereotactically injected into the right striatum at day 1 after MCAO. Behavioral tests were performed at day 1, 7, and 14 after MCAO using the modified Neurological Severity Score (mNSS) and cylinder test. Rats were euthanized at day 15 after MCAO for mRNA level evaluation of ischemic infarct area, endogenous neurogenesis, angiogenesis, and expression of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF). The rats were randomly assigned to one of the four groups: vehicle, Ex, SB623, and SB623 + Ex groups. RESULTS: SB623 + Ex group achieved significant neurological recovery in mNSS compared to the vehicle group (p < 0.05). The cerebral infarct area of SB623 + Ex group was significantly decreased compared to those in all other groups (p < 0.05). The number of BrdU/Doublecortin (Dcx) double-positive cells in the subventricular zone (SVZ) and the dentate gyrus (DG), the laminin-positive area in the ischemic boundary zone (IBZ), and the mRNA level of BDNF and VEGF in SB623 + Ex group were significantly increased compared to those in all other groups (p < 0.05). CONCLUSIONS: This study suggests that combination therapy of intracerebral transplantation SB623 cells and voluntary exercise with RW achieves robust neurological recovery and synergistically promotes endogenous neurogenesis and angiogenesis after cerebral ischemia, possibly through a mechanism involving the up-regulation of BDNF and VEGF.

A Rare Case of Idiopathic Spinal Cord Herniation Treated by DuraGen® Collagen Matrix Graft.

We report a rare case of idiopathic spinal cord herniation (ISCH) with a history of cerebrospinal fluid (CSF) leakage. ISCH is a protrusion of the spinal cord through a dural defect. Thin constructive interference in steady-state (CISS) images clearly demonstrated the herniated cord in the present case. The myelopathy worsened and the patient underwent surgery for reduction of herniated spinal cord; the dural defect was filled by placing collagen matrix graft (DuraGen®) between the inner and outer dural layers. The patient's symptoms have improved without relapse for 8 months since surgery. This method may be a good surgical option for cases of spinal cord herniation.

Two Cases of Monozygotic Twins with Early-onset Isolated (DYT1) Dystonia Effectively Treated with Bilateral Globus Pallidus Internus Stimulation.

Early-onset isolated (DYT1) dystonia is one of the most common forms of primary dystonia in childhood, and deep brain stimulation of the globus pallidus internus (GPi-DBS) is a highly effective treatment for it. However, the effectiveness of GPi-DBS in monozygotic twins with DYT1 dystonia has never been reported globally. Here, we report the cases of monozygotic twins with DYT1 dystonia who were treated using GPi-DBS, and we include a literature review. The younger brother showed an abnormal gait, with external rotation of the right lower leg at 6 years old. The symptoms gradually became so severe that he had difficulty walking on his own at 9 years of age. Treatment with levodopa-carbidopa partially resolved his symptoms, but most of the symptoms remained. Meanwhile, the older brother developed dystonia in both upper limbs at 8 years of age, with gradual symptom progression. At 13 years of age, they were diagnosed with DYT1 dystonia. Bilateral GPi-DBS was performed in both patients at 16 years of age. Their symptoms remarkably improved after surgery. The Burke-Fahn-Marsden dystonia rating scale (BFMDRS) movement score was reduced from 52 to 2 points for the younger brother and from 35 to 1 point for the older brother. Even if monozygotic twins have the same genes, the onset and severity of symptoms might vary in accordance with differences in epigenomic profiles. However, GPi-DBS treatment was very effective for the two cases; thus, we should consider the surgical interventions for each patient.

A Case of a Solitary Cortical Tuber with No Other Manifestations of Tuberous Sclerosis Complex Mimicking Focal Cortical Dysplasia Type II with Calcification.

Cortical tubers are one of the typical intracranial manifestations of tuberous sclerosis complex (TSC). Multiple cortical tubers are easy to diagnose as TSC; however, a solitary cortical tuber without any other cutaneous or visceral organ manifestations can be confused with other conditions, particularly focal cortical dysplasia. We report a surgical case of refractory epilepsy caused by a solitary cortical tuber mimicking focal cortical dysplasia type II, and describe the radiological, electrophysiological, and histopathological findings of our case.

A Pediatric Case of Cauda Equina Dermoid Cyst Resected by Minimally Invasive Unilateral Hemilaminectomy.

A 3-year-old boy had difficulty sitting up and walking for several months. Magnetic resonance imaging (MRI) revealed an intradural tumor at the L3-4 level. The tumor was successfully resected by unilateral hemilaminectomy and diagnosed as dermoid cyst. The patient had an uneventful postoperative course without pain, and MRI found no recurrence after surgery. A small bone defect remained that might be favorably reconstructed with autologous and artificial bone. Hemilaminectomy allowed us to resect the cauda equina dermoid cyst with minimal invasiveness. Pediatric patients require follow-up as they are more likely to experience spinal deformity or instability after surgery.

[Lumbar Degenerative Disease:Key for Diagnosis].

Accurate diagnosis is important for lumbar degenerative diseases. Patients' history, neurological examination, and diagnostic imaging are the three pillars for accurate diagnosis. While collecting medical history, 5W1H of the symptoms should be considered. Muscle strength, pain and numbness, and deep tendon reflex are the basic parameters in the neurological examination. A combination of the results of each tool is needed to facilitate precise diagnosis. This should be followed by diagnostic imaging to confirm the diagnosis. We feel relieved when neurological examination and diagnostic imaging reveals congruent results. The symptoms of lumbar degenerative diseases are the results of[static factors: the stenosis of the canal/intervertebral foramen]×[dynamic factor: the instability]. The T2-weighted MRI images effectively reveal canal/intervertebral foramen stenosis. Short-T1 inversion recovery(STIR)of MRI reveals early fractures and inflammation of the spine. CT findings help to imagine the process of drilling and screw insertion. A whole spine X-ray is good to reveal spinal alignment. Roentogenkymography with anteflexion/retroflexion reveals the instability of the lumbar spine. Myelography is effective in knowing the cerebrospinal fluid flow in a standing position. Therefore, accurate diagnosis and careful treatment are needed to obtain the appropriate outcome for a prolonged period after spinal surgery.

Ultra-high-molecular-weight Polyethylene (UHMWPE) Wing Method for Strong Cranioplasty.

We developed a new cranioplasty method that utilizes artificial bone made of ultra-high-molecular-weight polyethylene, with a wedge-shaped edge (UHMWPE Wing). This study shows the methods and data of case series and finite element analyses with the UHMWPE Wing. A circumferential wing was preoperatively designed for a custom-made artificial bone made of UHMWPE to achieve high fixed power and to minimize the usage of cranial implants. Here, we present 4 years of follow-up data and finite element analyses for patients treated with the UHMWPE Wing between February 2015 and February 2019. Eighteen consecutive patients underwent cranioplasty using our UHMWPE Wing design. There were no postoperative adverse events in 17 of the patients for at least 18 months. One case of hydrocephalus experienced screw loosening and graft uplift due to shunt malfunction. Placement of a ventriculo-peritoneal shunt immediately returned the artificial bone to normal position. Finite element analyses revealed that a model using the UHMWPE Wing had the highest withstand load and lowest deformation. This is the first report on the UHMWPE Wing method. This method may enable clinicians to minimize dead space and achieve high strength in cranioplasty.

4-Hydroxyl-2-Nonenal Localized Expression Pattern in Retrieved Clots is Associated with Large Artery Atherosclerosis in Stroke Patients.

OBJECTIVES: The relationship between stroke etiology and clot pathology remains controversial. MATERIALS AND METHODS: We performed histological analysis of clots retrieved from 52 acute ischemic stroke patients using hematoxylin and eosin staining and immunohistochemistry (CD42b and oxidative/hypoxic stress markers). The correlations between clot composition and the stroke etiological group (i.e., cardioembolic, cryptogenic, or large artery atherosclerosis) were assessed. RESULTS: Of the 52 clots analyzed, there were no significant differences in histopathologic composition (e.g., white blood cells, red blood cells, fibrin, and platelets) between the 3 etiological groups (P = .92). By contrast, all large artery atherosclerosis clots showed a localized pattern with the oxidative stress marker 4-hydroxyl-2-nonenal (P < .01). From all 52 clots, 4-hydroxyl-2-nonenal expression patterns were localized in 28.8% of clots, diffuse in 57.7% of clots, and no signal in 13.5% of clots. CONCLUSIONS: A localized pattern of 4-hydroxyl-2-nonenal staining may be a novel and effective marker for large artery atherosclerosis (sensitivity 100%, specificity 82%).

Arteriovenous Fistula at the Craniocervical Junction Found After Cervical Laminoplasty for Ossification of the Posterior Longitudinal Ligament.

Ossification of the posterior longitudinal ligament (OPLL) is common in East Asia. Arteriovenous fistula at the craniocervical junction (CCJ-AVF), in contrast, is rare. As OPLL occurs most often in the cervical region, these 2 conditions can coexist in the cervical spinal canal of a single patient. We report a case of CCJ-AVF found after cervical laminoplasty (CLP) for OPLL. A 68-year-old man experienced progressive myelopathy due to cervical OPLL. Magnetic resonance imaging (MRI) revealed a high-intensity area inside the spinal cord. CLP was performed and his symptoms immediately improved. Three months after CLP, however, myelopathy recurred. MRI revealed an exacerbated and enlarged high-intensity area inside the cord from the medulla oblongata to the C4/5 level with a flow void around the cord. Left vertebral artery angiography revealed CCJ-AVF with ascending and descending draining veins. Direct surgery was performed to interrupt shunt flow into the draining veins. The patient's symptoms improved to a limited degree. In this case, increased pressure inside the spinal canal due to OPLL might have decreased the shunt flow of the CCJ-AVF. Thus, the venous congestion induced by CCJ-AVF might have been exacerbated after the pressure was removed by CLP. Magnetic resonance angiography screening could help detect concurrent CCJ-AVF and OPLL.

Identification of Somatotopic Organization and Optimal Stimulation Site Within the Subthalamic Nucleus for Parkinson's Disease.

BACKGROUND: Details of the somatotopy within the subthalamic nucleus (STN) are still poorly understood; however, the STN is a common target of deep brain stimulation (DBS) for Parkinson disease. OBJECTIVE: To examine somatotopic organization within the STN and identify optimal stimulation sites from 77 surgical cases with microelectrode recording. METHODS: STN-DBS was performed for 77 patients with Parkinson disease between 2010 and 2014. We performed passive movements of each joint and captured single neuronal activities to identify movement-related cells (MRCs). The sites of MRCs and active contacts were determined by measuring their distances from the first contact of DBS electrode. Their positional correlations were directly and indirectly analyzed. RESULTS: The number of obtained MRCs was 264, of which 151 responded to multiple joints. The average x-, y-, and z-coordinates of the cells of the upper and lower limbs from the midcommisural point were 13.1 ± 1.1 and 12.7 ± 1.2, 0.22 ± 1.3 and -0.45 ± 1.5, and -2.5 ± 1.1 and -3.0 ± 1.4 mm, respectively. Most MRCs were distributed in the upper third of the STN, in its superior, lateral, and posterior regions, along the DBS electrode routes. Active contacts were observed to lie slightly inferior, medial, and posterior to the average MRC position. CONCLUSION: Somatotopic organization of the STN was easier to observe in the present study than in previous studies. Optimal stimulation sites were located inferior, medial, and posterior to the average MRC location. The sites may correspond to associative or motor parts through which fibers from the supplementary motor area pass.

Efficacy of Dural Sealant System for Preventing Brain Shift and Improving Accuracy in Deep Brain Stimulation Surgery.

The success of deep brain stimulation (DBS) depends heavily on surgical accuracy, and brain shift is recognized as a significant factor influencing accuracy. We investigated the factors associated with surgical accuracy and showed the effectiveness of a dural sealant system for preventing brain shift in 32 consecutive cases receiving DBS. Thirty-two patients receiving DBS between March 2014 and May 2015 were included in this study. We employed conventional burr hole techniques for the first 18 cases (Group I) and a dural sealant system (DuraSeal) for the subsequent 14 cases (Group II). We measured gaps between the actual positions of electrodes and the predetermined target positions. We then retrospectively evaluated the factors involved in surgical accuracy. The average gap between an electrode's actual and target positions was 1.55 ± 0.83 mm in all cases. Postoperative subdural air volume e, the only factor associated with surgical accuracy (r = 0.536, P < 0.0001), was significantly smaller in Group II (Group I: 43.9 ± 27.7, Group II: 12.1 ± 12.5 ml, P = 0.0006). The average electrode position gap was also significantly smaller in Group II (Group I: 1.77 ± 0.91, Group II: 1.27 ± 0.59 mm, P = 0.035). Use of a dural sealant system could significantly reduce intracranial air volume, which should improve surgical accuracy.

Spinal Extradural Arachnoid Cyst: Significance of Intrathecal Infusion after Fistula Closure.

The spinal extradural arachnoid cyst is a rare entity. Obtaining the correct diagnosis and detecting the fistula location are critical for providing effective treatment. A 41-year-old man had numbness in the soles of his feet for 2 years with accompanying gait disturbance, and a defecation disorder. Computed tomography myelography performed at another hospital revealed an epidural arachnoid cyst from Th11 to L2. He received a subarachnoid-cyst shunt at the rostral part of the cyst. However, his symptoms worsened and he was admitted to our hospital. Neuroradiological investigations revealed the correct location of the fistula at the level of Th12. We performed partial removal of the cyst wall with fistula closure via right hemilaminectomy of Th11 and 12. The complete closure of the fistula was confirmed by intrathecal infusion of artificial cerebrospinal fluid through the shunt tube. The shunt tube was removed with the sutures. The patient's symptoms improved, although numbness remained in his bilateral heels. There has been no recurrence in 15 months since the surgery. Fistula closure may work as a balanced therapeutic strategy for spinal extradural arachnoid cyst, and intrathecal cerebrospinal fluid infusion is useful for the confirmation of complete fistula closure.

Efficacy of Fiber Tractography in the Stereotactic Surgery of the Thalamus for Patients with Essential Tremor.

Several targets and targeting methods are utilized in stereotactic surgery to achieve tremor suppression for patients with intractable tremor. Recent developments in magnetic resonance imaging, including diffusion tensor imaging, have enabled the setting of appropriate targets in stereotactic surgery. In this retrospective study, the optimal target to suppress tremors in stereotactic surgery was explored using diffusion tensor image-based fiber tractography. Four tracts were focused on in this study, namely: the cerebello-thalamo-premotor cortical fiber tract, cerebello-thalamo-primary motor cortical fiber tract, spino-thalamo-somatosensory cortical fiber tract, and pyramidal tract. In 10 patients with essential tremor, we evaluated the thalamotomy lesions and active contacts of the lead in thalamic stimulation by diffusion tensor image-based fiber tractography to reveal which part of the cerebral cortex is most affected by stereotactic surgery. Tremor suppression and adverse events were also evaluated in the patients involved in this study. Consequently, the good tremor suppression was achieved in all patients. There had been no permanent adverse events 3 months after surgery. Twelve lesions in thalamotomy patients or active contacts of the lead in thalamic stimulation patients were on the cerebello-thalamo-premotor cortical fiber tract (12/14 lesions or active contacts: 86%). In conclusion, the cerebello-thalamo-premotor cortical fiber tract may be an optimal target for tremor suppression. Diffusion tensor image-based fiber tractography may enable us to both determine the optimal target to achieve strong tremor suppression and to reduce the number of adverse events by keeping lesions or electrodes away from important fiber tracts, such as the pyramidal tract and spinothalamic fibers.

Surgery in the Standing Position by a Surgeon with Achilles Tendon Rupture.

Unexpected injuries can have a profound effect on a surgeon's performance and thus on patients and surgical departments. Here we describe a technique for performing surgery in the standing position, as done by a surgeon with an Achilles tendon rupture. During his prescribed 45-day non-weight-bearing period for the left ankle after surgery for an Achilles tendon rupture, the surgeon was able to participate in 15 surgeries as an operator or assistant, due to his use of a combination of injured-leg genuflection on a stool and a 'Surgical Body Support' device. Similarly injured surgeons may benefit from such support.