Myotomy and Selective Peripheral Denervation Based on 18F-FDG PET/CT in Intractable Cervical Dystonia: A Case Report.

Cervical dystonia, characterized by the involuntary contraction of cervical muscles, is the most common form of adult dystonia. In a patient with intractable cervical dystonia, we carried out a myotomy of the left obliquus capitis inferior and selective peripheral denervation (SPD) of the posterior branches of the C3-C6 spinal nerves based on preoperative 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). The patient was a 65-year-old, right-handed man with an unremarkable medical history. His head rotated involuntarily to the left. Medication and botulinum toxin injections were ineffective, and surgical treatment was considered. 18F-FDG PET/CT imaging revealed FDG uptake in the left obliquus capitis inferior, right sternocleidomastoideus, and left splenius capitis. Myotomy of the left obliquus capitis inferior and SPD of the posterior branches of the C3-C6 spinal nerves was performed under general anesthesia. During the 6-month follow-up, the patient's Toronto Western Spasmodic Torticollis Rating Scale score improved from 35 to 9. This case shows that preoperative 18F-FDG PET/CT is effective in identifying dystonic muscles and determining the surgical strategy for cervical dystonia.

A Case of Cavernous Malformation of the Midbrain Removed via an Interhemispheric Transcallosal Subchoroidal Approach.

Cavernous malformations of the midbrain have a higher rate of hemorrhage and a poorer prognosis than vascular malformations of other brain areas. Surgical resection of these lesions is often necessary to avoid neurological deficits in affected patients. Herein, the literature surrounding cavernous malformations was examined, and the case of a 48-year-old man with left hemiparesis and diplopia caused by incomplete right oculomotor nerve palsy, who was diagnosed with a hemorrhage from a midbrain cavernous malformation, was discussed. The lesion expanded gradually on magnetic resonance imaging and was symptomatic; radical removal of the lesion before the onset of irreversible symptoms due to recurring bleeding was therefore considered to be beneficial for the patient. Surgical removal of the entire cavernous malformations of the midbrain was performed using an interhemispheric transcallosal subchoroidal approach, with excellent postoperative results and complete recovery from the oculomotor nerve palsy and left hemiparesis. This case shows that this approach is the most appropriate for surgical resections of lesions in the upper midbrain.

An Experience With an Exoscope System (ORBEYE) for Surgery for Tarsal Tunnel Syndrome: A Case Report.

Surgery for peripheral entrapment neuropathy aims to decompress the affected nerve and optimize the visualization of anatomical details during surgery. This paper describes our experience using the ORBEYE exoscope (Olympus) during surgery for tarsal tunnel syndrome (TTS). The patient was a 70-year-old male with complaints of bilateral pain and numbness on the plantar surface of the bilateral soles and medial halves of both lower limbs. He was diagnosed with idiopathic TTS with the American Orthopedic Foot and Ankle Score (AOFAS) of 20/100. Surgery for the right foot was performed under local anesthesia with the patient's body in the lateral position. All procedures were performed using the ORBEYE exoscope view. The posterior tibial artery (PTA) was transposed, and the flexor retinaculum was reconstructed between the PTA and posterior tibial nerve. Indocyanine green (ICG) video angiography confirmed the absence of PTA flow disturbance. One month after the first operation, left foot surgery was performed. Three months later, the AOFAS had improved from 20/100 to 50/100. The ORBEYE exoscope is useful in TTS treatment and represents a feasible and comfortable technique for entrapment neuropathy surgery. In addition, ICG capability is an effective tool for confirming blood flow in PTA after transposition.

Successful treatment of focal hand dystonia after cervical whiplash injury by thalamotomy.

Background: Posttraumatic focal hand dystonia after cervical whiplash injury is rare. Moreover, the treatment of peripheral posttraumatic dystonia is usually ineffective. Herein, we report a case of successful thalamotomy for a patient with focal hand dystonia after cervical whiplash injury. Case Description: A 39-year-old woman was hit from behind by a car; subsequently, she felt strange in the right hand and was diagnosed with whiplash injury. A month later, she developed a persistent abnormal posture of the right hand. Brain imaging showed no lesions, and cervical magnetic resonance imaging showed stenosis but no spinal cord signal changes. Posttraumatic dystonia was diagnosed, for which the patient underwent left ventro-oral (Vo) thalamotomy. One year after the first surgery, the patient underwent left Vo and ventral intermediate nucleus (Vim) thalamotomy due to recurrence of dystonia. Nine years after the second surgery, the patient continues to be able to maintain her normal physical routine. Conclusion: Vo-Vim thalamotomy may be a feasible and effective treatment for focal hand dystonia after cervical whiplash injury.

Postoperative 18F-FDG-PET/CT documents efficacy of selective peripheral denervation for treating cervical dystonia.

Background: Cervical dystonia, characterized by involuntary contraction of the cervical muscles, is the most common form of adult dystonia. We compared the preoperative versus postoperative 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) scans to confirm the efficacy of selective peripheral denervation (SPD) for treating cervical dystonia. Case Description: A 38-year-old male with the right-sided cervical dystonia underwent a left pallidothalamic tractotomy. However, the involuntary neck movement persisted and correlated with the 18F-FDG-PET/CT imaging that showed persistent FDG uptake in the right obliquus capitis inferior muscle. A subsequent SPD resulted in resolution of the dystonia that correlated with lack of further 18F-FDG-PET/CT uptake in the right obliquus capitis inferior muscle. Conclusion: The postoperative 18F-FDG-PET/CT documented the efficacy of an SPD in resolving a patient's cervical dystonia.

C6 nerve root palsy after double-door cervical laminoplasty.

BACKGROUND: This study correlated the relationship between postoperative C6 nerve root palsies and various patient-related clinical, radiographic, and surgical parameters. METHODS: The medical records of 318 patients undergoing double-door cervical laminoplasty for myelopathy were reviewed. Twelve (3.8%) had postoperative C6 nerve root palsies. Their clinical, radiographic, and surgical procedures were analyzed looking for a correlation/explanation for these new C6 root deficits. RESULTS: The following factors correlated with patients' developing new postoperative C6 nerve root deficit following double-door cervical laminoplasty; a high correlation with additional C5 palsies, narrower C6 intervertebral foraminal widths, greater anterior protrusions of the C6 articular process, and larger posterior shifts of the spinal cord on magnetic resonance (MR) between the C4/C5-C6/C7 levels. CONCLUSION: Factors correlating with the new onset of C6 nerve root palsies following double-door cervical laminoplasty included; a high correlation with new C5 palsies, more severe foraminal stenosis, greater anterior protrusions of the C6 articular process, and more extensive dorsal spinal cord migration.

Prevalence and Screening of Deep Vein Thrombosis in Patients with Osteoporotic Vertebral Fracture.

AIM: To determine the prevalence of a deep vein thrombosis (DVT) in osteoporotic vertebral fractures. MATERIAL AND METHODS: Data were retrospectively collected from the medical records of 50 patients who were admitted to the Kameda Medical Center for osteoporotic vertebral fracture from 2019 to 2020. Inpatients were screened for DVT using D-dimer, and those who were screened positive underwent lower extremity venous ultrasonography to confirm DVT. Associations between various clinical factors and DVT were analyzed. RESULTS: Six (12.0%) inpatients with osteoporotic vertebral fractures were found to have DVT. Two (33.3%) of the six had proximal DVT, although no pulmonary embolism was detected by chest computed tomography angiography. Univariate analysis showed that D-dimer values and duration from onset to hospitalization were predictive of DVT (p < 0.05). CONCLUSION: The prevalence of DVT among inpatients with osteoporotic vertebral fractures was 12.0%. This finding emphasizes the importance of DVT screening using D-dimer in those with osteoporotic vertebral fractures.

Two cases of normal pressure hydrocephalus caused by ependymoma of the cauda equina.

BACKGROUND: Normal pressure hydrocephalus (NPH) associated with tumors of the cauda equina is rare. Here, we report two cases of NPH attributed to cauda equina ependymomas. CASE DESCRIPTION: A 63-year-old male presented with progressive gait disturbance, dementia, and urinary incontinence. When the lumbar MR documented an intradural tumor involving the cauda equina at the L2-L3 level; the tumor was excised; pathologically, it proved to be a myxopapillary ependymoma. Postoperatively, however, the patient's continued gait disturbance led to a brain CT that documented ventricular dilation consistent with NPH; following ventriculoperitoneal (VP) shunt placement his symptoms improved. A 65-year-old female also presented with gait disturbance, dementia, and urinary retention. Here, procedures were performed in reverse. When a brain CT showed hydrocephalus, a VP shunt was placed. When symptoms persisted, a lumbar MR demonstrated a T12-L2 intradural tumor; following a lumbar laminectomy for tumor excision, symptoms stabilized. The pathological diagnosis was also consistent with a conus/cauda equina ependymoma. Over the next 10 years, the patient had residual bladder dysfunction (e.g., requiring straight catheterization), but had no shunt dysfunction. CONCLUSION: We observed two cases of ependymomas of the cauda equina and brain CTs documenting NPH that was successfully surgically managed with stabilization of neurological deficit. In the first case, L2-L3 laminectomy for tumor removal was succeeded by shunting for NPH, while in the second case, initial VP shunting for NPH was followed by a T12-L2 laminectomy for tumor excision.

Effect of asymptomatic postoperative epidural hematoma on recovery rate after surgery for myelopathy caused by thoracic ossified ligamentum flavum.

AIM: To analyze the clinical characteristics of thoracic ossified ligamentum flavum (OLF) and clarify prognostic factors. MATERIAL AND METHODS: We retrospectively collected clinical data from the medical records of 29 patients who underwent decompressive surgery for myelopathy caused by thoracic OLF from 2011 to 2019. Associations between various clinical and radiological factors and surgical outcomes were analyzed. RESULTS: The mean preoperative and final follow-up modified Japanese Orthopaedic Association scores were 6.7 and 7.9 points, respectively (mean follow-up period, 22.4 months; P 0.0001). Univariate analysis revealed that preoperative symptom duration and postoperative epidural hematoma on magnetic resonance imaging (MRI) were significant surgical outcome predictors. The recovery rate was higher in patients without postoperative epidural hematoma (n = 16) than in those with postoperative epidural hematoma (n = 13; 38.7% ± 28.1% vs. 12.9% ± 24.4% mm; P = 0.01). Multiple regression analysis showed that postoperative epidural hematoma on MRI was a significant surgical outcome predictor (P 0.05). CONCLUSION: Posterior decompressive laminectomy and resection of OLF can be considered effective. Postoperative epidural hematoma on MRI may be an important surgical outcome predictor.

Encoding of social exploration by neural ensembles in the insular cortex.

The insular cortex (IC) participates in diverse complex brain functions, including social function, yet their cellular bases remain to be fully understood. Using microendoscopic calcium imaging of the agranular insular cortex (AI) in mice interacting with freely moving and restrained social targets, we identified 2 subsets of AI neurons-a larger fraction of "Social-ON" cells and a smaller fraction of "Social-OFF" cells-that change their activity in opposite directions during social exploration. Social-ON cells included those that represented social investigation independent of location and consisted of multiple subsets, each of which was preferentially active during exploration under a particular behavioral state or with a particular target of physical contact. These results uncover a previously unknown function of AI neurons that may act to monitor the ongoing status of social exploration while an animal interacts with unfamiliar conspecifics.

Imaging the Neural Circuit Basis of Social Behavior: Insights from Mouse and Human Studies.

Social behavior includes a variety of behaviors that are expressed between two or more individuals. In humans, impairment of social function (i.e., social behavior and social cognition) is seen in neurodevelopmental and neurological disorders including autism spectrum disorders (ASDs) and stroke, respectively. In basic neuroscience research, fluorescence monitoring of neural activity, such as immediate early gene (IEG)-mediated whole-brain mapping, fiber photometry, and calcium imaging using a miniaturized head-mounted microscope or a two-photon microscope, and non-fluorescence imaging such as functional magnetic resonance imaging (fMRI) are increasingly used to measure the activity of many neurons and multiple brain areas in animals during social behavior. In this review, we overview recent rodent studies that have investigated the dynamics of brain activity during social behavior at the whole-brain and local circuit levels and studies that explored the neural basis of social function in healthy, in brain-injured, and in autistic human subjects. A synthesis of such findings will advance our understanding of brain mechanisms underlying social behavior and facilitate the development of pharmaceutical and functional neurosurgical interventions for brain disorders affecting social function.

Tumoral Calcinosis of Thoracic Spine Associated with Vertebral Fracture and Inflammatory Reactions.

Tumoral calcinosis involving the spine is rare. The involvement of the thoracic spine is rarer than that of the cervical or lumbar spine. We report a case of thoracic tumoral calcinosis accompanied by vertebral fracture with increased concentrations of inflammatory markers and no abnormalities in serum calcinosis and phosphorus concentration. A 60-year-old woman presented with complete paraplegia. Her white blood cell count and C-reactive protein (CRP) concentration were elevated. The thoracic magnetic resonance imaging revealed vertebral fracture and an epidural mass that demonstrated low intensity on both T2- and T1-weighted images at the T9/10 dorsal side of the central canal. This lesion is larger in size than that observed in the previous 2 months. Her laboratory data showed signs of infection, and only decompression surgery without fixation for treatment and diagnosis was performed. Histopathological examination was consistent with tumoral calcinosis. Postoperatively, the patient's white cell count and CRP concentration were normalized. We found that tumoral calcinosis can occur at the thoracic level on the basis of the spinal instability due to the vertebral compression fracture and the accompanying increase in inflammation indicated by increased white blood cell count and CRP concentration.

Spinal Subdural Abscess following Transforaminal Lumbar Interbody Fusion.

Spinal subdural abscesses are rare lesions. We report the case of surgical site infection complicated with meningitis and rapidly progressive spinal subdural abscess caused by P. aeruginosa following transforaminal lumbar interbody fusion (TLIF). A 72-year-old woman was admitted to our hospital complaining of drop foot syndrome and sciatica caused by stenosis of the L5/6 intervertebral foramen accompanied by L5 lumbar vertebral fracture. Accordingly, TLIF of L5-L6 and balloon kyphoplasty of L5 were performed. On the 3rd postoperative day (POD), she was diagnosed with surgical site infection complicated with bacterial meningitis. Subcutaneous fluid, blood, and cerebrospinal fluid cultures indicated P. aeruginosa. On the 7th POD, a repeat MRI showed a large dorsal fluid collection consistent with a subdural infection and massive cauda equina compression. We performed debridement and instrument removal and found a dural laceration that was not observed during the first operation. An intraoperative insensible dural laceration may cause bacteria intrusion into the subdural space.

A Rapidly Growing Cervical Meningeal Melanocytoma with a Dumbbell-Shaped Extension.

BACKGROUND: Meningeal melanocytoma is a rare benign lesion found in the central nervous system. Preoperative diagnosis of meningeal melanocytoma is often a diagnostic challenge, as the clinical and neurologic features are often nonspecific. Various characteristics, including the natural course of this tumor, remain poorly understood. We report a case of a rapidly growing dumbbell-shaped melanocytoma compressing the spinal cord that manifested 2 years after a tumor was identified at the right C2-C3 foramen. CASE DESCRIPTION: A 40-year-old, right-handed man presented with a 2-month history of right palm and left leg numbness. Magnetic resonance imaging of the cervical spine showed a dumbbell-shaped tumor at the right C2-C3 foramen with extension into the central canal. The lesion was hyperintense on T1-weighted images and hypointense to isointense on T2-weighted images. Contrast enhancement was not visualized clearly. Fluorodeoxyglucose-positron emission tomography with computed tomography showed intense uptake in the lesion. The patient's history included a small lesion that had been localized at the right C2-C3 foramen 2 years before admission. The pathologic findings were consistent with melanocytoma. CONCLUSIONS: It is important to include meningeal melanocytoma in the differential diagnosis of dumbbell tumors, as meningeal melanocytomas may show rapid progression.

Basilar invagination in a child with atlanto-occipital subluxation and suspected prenatal Dandy-Walker malformation.

BACKGROUND AND PURPOSE: Although advances in imaging have allowed earlier and more accurate diagnosis of various fetal anomalies, Dandy-Walker malformation (DWM) remains one of the more challenging central nervous system anomalies to diagnose accurately before birth. Basilar invagination (BI), which is a dislocation of the dens in an upward direction, is occasionally accompanied by Klippel-Feil syndrome (KFS). We report a pediatric case of BI caused by atlanto-occipital subluxation (AOS) in KFS, suspected of having DWM prenatally but head magnetic resonance images (MRI) showed no evidence of that at 7 months of age. CASE: At 28 weeks of gestation, fetal MRI study revealed a small cerebellar vermis, leading us to suspect a DWM. The patient was born at 40 weeks of gestation. Head CT showed inferior vermian hypoplasia without findings of hydrocephalus. Cervicothoracic CT showed cervical lamina assimilations, thoracic hemivertebrae, and cervicothoracic scoliosis. He was diagnosed with Dandy-Walker variant and KFS. At 7 months of age, head MRI showed near normal cerebellum and vermis and there was no evidence of the DWM. He did not have intellectual or developmental delay and imaging studies were performed periodically. At 9 years of age, an already existing cough headache deteriorated. Three-dimensional reconstructed images from CT scan showed C1 hypoplasia, fusion of C1 and C2, BI, and AOS. Sagittal T2-weighted MRI showed protrusion of cerebellar tonsils inferiorly to the level of the posterior arch of C2. Serum calcium, phosphate, and parathyroid hormone levels were normal. The diagnosis was tonsillar herniation related to BI following AOS in KFS. Posterior occipitocervical fixation was performed under traction. CONCLUSIONS: We found out two important clinical issues: DWM findings after birth can be disappearing and BI can present sequential deterioration because of AOS in KFS. Our observation indicated the possible prognosis of pediatric BI with long follow-up and can help us decide on its surgical treatment timing when associated with AOS.

Lumbar Ganglioneuroma from the Paravertebral Body Presenting in Continuity Between Intradural and Extradural Spaces.

BACKGROUND: Ganglioneuroma is a well-differentiated benign tumor that develops from the ganglion cells of the posterior mediastinum, retroperitoneum, cervical spine, and adrenal glands. The paravertebral body, in which the sympathetic trunk exists, is a common tumor site, and tumor sometimes invades the spinal canal through the intervertebral foramen. There have been no reports regarding tumors with intradural and extradural continuity. We report a paravertebral ganglioneuroma extending between the intradural and extradural spaces and its surgical treatment. CASE DESCRIPTION: A 33-year-old man was admitted to the hospital with progressive left lower limb numbness. A dumbbell-type tumor progressing to the spinal canal via the left intervertebral foramen from the paravertebral body at L1-2 was detected, and intradural calcified lesions were found. Pathologic examination of a computed tomography-guided biopsy sample revealed a ganglioglioma. The extradural tumor was removed; however, the left lower limb pain gradually worsened. As complete block was observed on myelography, the intradural tumor was removed 8 months later. Intraoperative findings revealed that the intradural and extradural tumors were continuous through the L1 nerve root. CONCLUSIONS: This is the first known reported case of paravertebral ganglioneuroma presenting in continuity between the intradural and extradural spaces.

Extracranial internal carotid artery vasospasm during thrombectomy.

The use of a stent retriever increases the risk of intracranial vasospasm. Here, we report the case of a man who developed severe vasospasm in a long segment of the extracranial internal carotid artery after mechanical irritation by a stent retriever inserted for the treatment of acute cerebral ischemia. A 47-year-old right-handed man presented with sudden-onset right-sided weakness and difficulty speaking. The patient's National Institutes of Health Stroke Scale score was 6 and he had an Alberta Stroke Program Early Computed Tomography Score of 9. The patient was started on intravenous alteplase therapy, and an acute thrombectomy was performed. Left internal carotid digital subtraction angiography showed narrowing of the left common and internal carotid arteries and occlusion of the proximal left M1 segment of the middle cerebral artery. A stent retriever was retracted into a guiding catheter placed at the left carotid bulb under continuous suction. Recanalization of the middle cerebral artery was not achieved and there was significant narrowing in a long segment of the extracranial internal carotid artery associated with exacerbation of the patient's aphasia. The cervical vasospasm improved after nicardipine infusion via the catheter. We encountered vasospasm in a long segment of the extracranial internal carotid artery after mechanical irritation by a stent retriever. If a stent retriever is used in a patient with a narrow extracranial internal carotid artery, consideration should be given to using a Penumbra or smaller guiding catheter located in the distal internal carotid artery to prevent irritation to the cervical vessel wall.

[A synovial cyst accompanied by asymptomatic lumbar vertebral fracture requiring differentiation from spinal metastasis].

We experienced a case with a synovial cyst accompanied by asymptomatic lumbar vertebral fracture that required differentiation from spinal metastasis. An 82-year-old man suffered from right leg and anal pain. Computed tomography (CT) showed L5 spondylolysis. Magnetic resonance images (MRI) revealed an intra spinal cyst and acute lumbar vertebral fracture of L5 vertebral body. The surrounding area of the cyst presented contrast enhancement, and the extradural mass compressed the dural sac. Bone scintigraphy with 99m technetium-MDP demonstrated intense uptake on the right first, fourth, fifth, and seventh ribs and L2, L3, and L5 vertebra. The F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) image demonstrated an increased radiotracer uptake in the L5 vertebra(standardized uptake value(SUV) max=3.5). Spinal metastasis was suspected. Because of the cauda equina compression syndrome, it was surgically removed. Intraoperatively, a well-demarcated extradural cyst was found and compressed the dural sac markedly. The cyst capsule was thin and contained clear, thin fluid with no signs of bleeding. The histological diagnosis was a synovial cyst. His neurological symptoms improved after the surgery. The synovial cyst may enlarge after asymptomatic vertebral fractures.

Functional plasticity of language confirmed with intraoperative electrical stimulations and updated neuronavigation: case report of low-grade glioma of the left inferior frontal gyrus.

Removal of glioma from the dominant side of the inferior frontal gyrus (IFG) is associated with a risk of permanent language dysfunction. While intraoperative cortical and subcortical electrical stimulations can be used for functional language mapping in an effort to reduce the risk of postoperative neurological impairment, the extent of resection is limited by the functional boundaries. Recent reports proposed that a two-stage surgical approach for low-grade glioma in eloquent areas could avoid permanent deficits via the functional plasticity that occurs between the two operations. The report describes a patient with World Health Organization (WHO) grade II oligoastrocytoma in the left IFG, in functional plasticity of language occurred in the interval between two consecutive surgeries. Intraoperative electrical stimulations suggested that a language area and related subcortical fiber crossed the pre-central sulcus during tumor progression owing to functional plasticity. In the present case, we integrated neurophysiological data into the intraoperative neuronavigation system. We also confirmed the peri-lesional shift of language area and related subcortical fiber on image findings. Consequently, the tumor was sub-totally removed with two separate resections. Permanent language disturbance did not occur, and this favorable outcome was attributed to functional plasticity. The present experience sustains the multistage approach for low-grade gliomas in the language area. A combination of intraoperative electrical stimulations and updated neuronavigation may facilitate the characterization of brain functional plasticity.