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Perianal Crohn's Disease (pCD) is a common manifestation of Crohn's Disease. Absence of reliable disease measures makes disease monitoring unreliable. Qualitative MRI has been increasingly used for diagnosing and monitoring pCD and has shown potential for assessing response to treatment. Quantitative MRI sequences, such as diffusion-weighted imaging (DWI), dynamic contrast enhancement (DCE) and magnetisation transfer (MT), along with T2 relaxometry, offer opportunities to improve diagnostic capability. Quantitative MRI sequences (DWI, DCE, MT and T2) were used in a cohort of 25 pCD patients before and 12 weeks after biological therapy at two different field strengths (1.5 and 3 T). Disease activity was measured with the Perianal Crohn's Disease Activity index (PDAI) and serum C-reactive protein (CRP). Diseased tissue areas on MRI were defined by a radiologist. A baseline model to predict outcome at 12 weeks was developed. No differences were seen in the quantitative MR measured in the diseased tissue regions from baseline to 12 weeks; however, PDAI and CRP decreased. Baseline PDAI, CRP, T2 relaxometry and surgical history were found to have a moderate ability to predict response after 12 weeks of biological treatment. Validation in larger cohorts with MRI and clinical measures are needed in order to further develop the model.

The syndrome of the supplementary motor area (SMA) is not well recognized and its features can easily be confused with pyramidal weakness. The authors describe the SMA syndrome in six patients who underwent surgery for tumours located in the SMA, three in the dominant and three in the non-dominant hemispheres. All of them underwent complete resection of the anatomically described SMA, with partial (n = 4) or total resection (n = 2) of the tumour. In the postoperative period, all these patients exhibited reduction of spontaneous movements and difficulty in performing voluntary motor acts to command in the contralateral limbs, although the tone in the limbs was maintained or increased. The function of these limbs in serial automatic motor activities (for example, dressing and walking) was, however, relatively unaffected. Speech deficits were seen in only one of three patients with the dominant SMA syndrome. Besides a severe impairment of volitional movements, the salient features of the deficits in this syndrome are hemineglect and dyspraxia or apraxia involving the contralateral limbs. All patients recovered their motor functions over varying periods of time ranging from one to a few weeks. Long-term follow-up (median 24 months) in five patients revealed complete return of function in the affected limbs. It is important to recognize the entity of the SMA syndrome and differentiate it from the deficits that result from operative damage to the motor cortex as the deficits associated with the former are likely to recover almost completely over a short period of time. [ABSTRACT FROM AUTHOR]

Chordomas constitute <5% of vertebral column tumours and a third of these arise in the upper cervical spine and tend to be clival - usually midline, with occasional eccentric extension. We report a case of cervical chordoma presenting as a lateral neck mass and discuss its origin, diagnosis and management.

Objective: The corticospinal tract (CST) is considered the most important motor output pathway comprising fibers from the primary motor cortex (M1) and various premotor areas. Damage to its descending fibers after stroke commonly leads to motor impairment. While premotor areas are thought to critically support motor recovery after stroke, the functional role of their corticospinal output for different aspects of post‐stroke motor control remains poorly understood. Methods: We assessed the differential role of CST fibers originating from premotor areas and M1 in the control of basal (single‐joint muscle synergies and strength) and complex motor control (involving inter‐joint coordination and visuomotor integration) using a novel diffusion imaging approach in chronic stroke patients. Results: While M1 sub‐tract anisotropy was positively correlated with basal and complex motor skills, anisotropy of PMd, PMv, and SMA sub‐tracts was exclusively associated with complex motor tasks. Interestingly, patients featuring persistent motor deficits showed an additional positive association between premotor sub‐tract integrity and basal motor control. Interpretation: While descending M1 output seems to be a prerequisite for any form of upper limb movements, complex motor skills critically depend on output from premotor areas after stroke. The additional involvement of premotor tracts in basal motor control in patients with persistent deficits emphasizes their compensatory capacity in post‐stroke motor control. In summary, our findings highlight the pivotal role of descending corticospinal output from premotor areas for motor control after stroke, which thus serve as prime candidates for future interventions to amplify motor recovery. [ABSTRACT FROM AUTHOR]

A rare case of a mid brain venous angioma with obstructive hydrocephalus is described. A dilated draining vein from the lesion in the aqueduct as the cause of the hydrocephalus is highlighted, and interesting features of the pathology of venous angiomas and associated cavernous hemangioma are described. The management of this interesting condition is discussed.

The treatment of arteriovenous malformations (AVMs) is still a challenging problem in the neurosurgical field. The deep-seated AVMs are a definite indication for radiosurgery for the small AVMs and with pre-embolisation for the large AVMs. The superficial AVMs are a good indication for surgery. In the case of small AVMs, surgery alone is a viable option; however, in the case of large AVMs, pre-operative embolisation is essential for prevention of NPPB (normal perfusion pressure breakthrough). Embolisation alone cannot be used, except for a small AVM in the non-eloquent cortex. Preoperative embolisation makes surgery easy; however, it causes the surrounding cortex to infarct. Hyperperfusion may occur after the direct removal of high-flow large AVMs, therefore postoperative management will be difficult in these cases. In eloquent cortex minimally invasive surgery is more reliable with respect to the morbidity produced. Therefore in cases of small AVMs in the functional cortex, direct surgery is the only choice. In cases of high-flow large AVMs, surgery and postoperative management are risky because of NPPB. Therefore pre-operative embolisation followed by surgery is a better choice. In high-flow AVMs, local blood circulation is not decreased by temporary clipping of the feeding arteries. So we recommend temporary clipping of all feeding arteries, even away from the nidus where it is easier to control bleeding.

Neurosurgery at the Fujita Health University began in 1972 with Dr. Tetsuo Kanno. In 1973, he was joined by Dr. Kazuhiro Katada and in the year 1976, an independent neurosurgery department was established with Dr. Kanno as the Chief of Neurosurgery. Under his guidance the department continued to grow and by 1978, a neurosurgical residency program recognised by the Japanese Board of Neurosurgery was established. Integration of laboratory research and clinical experience is the hallmark of this program. The current philosophy is directed towards subspecialization and academic training. This article provides a brief overview of the rapid development of a Neurosurgical Centre to reach international acclaim under the guidance of Prof. Tetsuo Kanno.

Stereotactic techniques were used to place a catheter into cystic intracranial lesions in 11 patients. These patients had 4 types of cystic lesions : suprasellar craniopharyngiomas (4), benign epithelial cysts (2), suprasellar arachnoid cysts (3) and tumour cysts (2). Seven patients had subgaleal reservoir placement and four had cystoperitoneal shunt. There was no procedure related morbidity. In all the patients, a post procedure CT scan revealed accurate placement of the catheter. The mean follow-up period was 23 months. During this period, 3 of the 7 patients with reservoir placement had become symptomatic and had to undergo a percutaneous aspiration of the cyst through the subgaleal reservoir. One patient required repositioning of a displaced catheter, and one patient received bleomycin through the reservoir after aspiration of the craniopharyngioma cyst. Eight patients improved and are leading independent lives. Stereotactic catheter placement is a minimally invasive, safe, accurate and simple procedure which can be used in the management of selected cystic masses in the brain. Connection of the catheter to a reservoir or a shunt ensures access to the cyst in case of reaccumulation of its contents and provides continuous drainage of its contents.

A case of histologically verified ventro-laterally placed enterogenous cyst in the upper cervical region is reported.

Intraoperative neurophysiological monitoring (IONM) is needed for evaluating and demonstrating the integrity of the central and peripheral nervous system during surgical manoeuvres that take place in proximity to eloquent motor and somatosensory nervous structures. The integrity of the monitored motor pathways is not always followed by consistent clinical normality, particularly in the first hours/days following surgery, when surgical resection involves brain structures such as the supplementary motor areas (SMA). We report the case of a patient who underwent surgical excision of a right frontal glioblastoma with normal preoperative, intraoperative (IONM), and postoperative central motor conduction, but with persistent postoperative hemiplegia (> 6 months). The literature regarding SMA syndrome and its diagnosis and prognosis is reviewed. [ABSTRACT FROM AUTHOR]

Background: The supplementary motor area (SMA) is important for motor and language function. Damage to the SMA may harm these functions, yet tools for a preoperative assessment of the area are still sparse. Objective: The aim of this study was to validate a mapping protocol using repetitive navigated transcranial magnetic stimulation (rnTMS) and extend this protocol for both hemispheres and lower extremities. Methods: To this purpose, the SMA of both hemispheres were mapped based on a finger tapping task for 30 healthy subjects (35.97 ± 15.11, range 21-67 years; 14 females) using rnTMS at 20 Hz (120% resting motor threshold (RMT)) while controlling for primary motor cortex activation. Points with induced errors were marked on the corresponding MRI. Next, on the identified SMA hotspot a bimanual finger tapping task and the Nine-Hole Peg Test (NHPT) were performed. Further, the lower extremity was mapped at 20 Hz (140%RMT) using a toe tapping task. Results: Mean finger tapping scores decreased significantly during stimulation (25.70taps) compared to baseline (30.48; p < 0.01). Bimanual finger tapping led to a significant increase in taps during stimulation (28.43taps) compared to unimanual tapping (p < 0.01). Compared to baseline, completion time for the NHPT increased significantly during stimulation (baseline: 13.6 s, stimulation: 16.4 s; p < 0.01). No differences between hemispheres were observed. Conclusion: The current study validated and extended a rnTMS based protocol for the mapping of the SMA regarding motor function of upper and lower extremity. This protocol could be beneficial to better understand functional SMA organisation and improve preoperative planning in patients with SMA lesions. [ABSTRACT FROM AUTHOR]

Hemifacial spasm (HFS) is a rare disorder characterized by involuntary facial muscle contractions. The primary cause is mechanical compression of the facial nerve by nearby structures. Lateral spread response (LSR) is an abnormal muscle response observed during electromyogram (EMG) testing and is associated with HFS. Intraoperative monitoring of LSR is crucial during surgery to confirm successful decompression. Proper anesthesia and electrode positioning are important for accurate LSR monitoring. Stimulation parameters should be carefully adjusted to avoid artifacts. The disappearance of LSR during surgery is associated with short-term outcomes, but its persistence does not necessarily indicate poor long-term outcomes. LSR monitoring has both positive and negative prognostic value, and its predictive ability varies across studies. Early disappearance of LSR can occur before decompression and may indicate better clinical outcomes. Further research is needed to fully understand the implications of LSR monitoring in HFS surgery. [ABSTRACT FROM AUTHOR]

Objectives: In amyotrophic lateral sclerosis (ALS), verbal fluency index (Vfi) is used to investigate fluency accounting for motor impairment. This study has three aims: (1) to provide Vfi reference values from a cohort of Italian healthy subjects; (2) to assess the ability of Vfi reference values (vs standard verbal fluency test [VFT]) in distinguishing ALS patients with and without executive dysfunction; and (3) to investigate the association between Vfi and brain structural features of ALS patients. Methods: We included 180 healthy subjects and 157 ALS patients who underwent neuropsychological assessment, including VFT and Vfi, and brain MRI. Healthy subjects were split into four subgroups according to sex and education. For each subgroup, we defined the 95th percentile of Vfi as the cutoff. In ALS, the distributions of "abnormal" cases based on Vfi and standard VFT cutoffs were compared using Fisher's exact test. Using quantile regressions in patients, we assessed the association between Vfi and VFT scores, separately, with gray matter volumes and white matter (WM) tract integrity. Results: Applying Vfi and VFT cutoffs, 9 and 13% of ALS cases, respectively, had abnormal scores (p < 0.001). In ALS, while higher Vfi scores were associated with WM changes of callosal fibers linking supplementary motor area, lower VFT performances related to corticospinal tract alterations. Discussion: We provided Italian reference values for the spoken Vfi. Compared to VFT, Vfis are critical to disentangle motor and cognitive deficits in ALS. In patients, abnormal Vfis were associated with damage to WM tracts specifically involved in ideational information processing. [ABSTRACT FROM AUTHOR]

Brodmann area 8 (BA8) is traditionally defined as the prefrontal region of the human cerebrum just anterior to the premotor cortices and enveloping most of the superior frontal gyrus. Early studies have suggested the frontal eye fields are situated at its most caudal aspect, causing many to consider BA8 as primarily an ocular center which controls contralateral gaze and attention. However, years of refinement in cytoarchitectural studies have challenged this traditional anatomical definition, providing a refined definition of its boundaries with neighboring cortical areas and the presence of meaningful subdivisions. Furthermore, functional imaging studies have suggested its involvement in a diverse number of higher-order functions, such as motor, cognition, and language. Thus, our traditional working definition of BA8 has likely been insufficient to truly understand the complex structural and functional significance of this area. Recently, large-scale multi-modal neuroimaging approaches have allowed for improved mapping of the neural connectivity of the human brain. Insight into the structural and functional connectivity of the brain connectome, comprised of large-scale brain networks, has allowed for greater understanding of complex neurological functioning and pathophysiological diseases states. Simultaneously, the structural and functional connectivity of BA8 has recently been highlighted in various neuroimaging studies and detailed anatomic dissections. However, while Brodmann's nomenclature is still widely used today, such as for clinical discussions and the communication of research findings, the importance of the underlying connectivity of BA8 requires further review. [ABSTRACT FROM AUTHOR]

Cavernous malformations (CMs) are benign vascular malformations that maybe seen anywhere in the central nervous system. They are dynamic lesions, growing or shrinking over time and only rarely remaining stable. Size varies from a few millimeters to a few centimeters. CMs can be sporadic or familial, and while most of them are congenital, de novo and acquired lesions may also be seen. Etiology is still unknown. A genetic molecular mechanism has been proposed since a cerebral cavernous malformation gene loss of function was found in both familial and sporadic lesions. Additionally, recent studies suggest that formation of CMs in humans may be associated with a distinctive bacterial gut composition (microbioma). Imaging is fairly typical but may vary according to age, location, and etiology. Follow‐up is not well established because CMs patients have a highly unpredictable clinical course. Angiogenic and inflammatory mechanisms have been implicated in disease activity, as well as lesional hyperpermeability and iron deposition. Imaging and serum biomarkers of these mechanisms are under current investigation. Treatment options, including surgery or radiosurgery, are not well defined and are dependent upon multiple factors, including clinical presentation, lesion location, number of hemorrhagic events, and medical comorbidities. Our purpose is to review the imaging features of CMs based on their size, location, and etiology, as well as their differential diagnosis and best imaging approach. New insights in etiology will be briefly considered. Follow‐up strategies, including serum and imaging biomarkers, and treatment options will also be discussed. [ABSTRACT FROM AUTHOR]

Childhood apraxia of speech (CAS) is a subtype of motor speech disorder usually co-occurring with language impairment. A supramodal processing difficulty, involving executive functions (EFs), might contribute to the cognitive endophenotypes and behavioral manifestations. The present study aimed to profile the EFs in CAS, investigating the relationship between EFs, speech and language severity, and the connectivity of the frontal aslant tract (FAT), a white matter tract involved in both speech and EFs. A total of 30 preschool children with CAS underwent speech, language, and EF assessments and brain MRIs. Their FAT connectivity metrics were compared to those of 30 children without other neurodevelopmental disorders (NoNDs), who also underwent brain MRIs. Alterations in some basic EF components were found. Inhibition and working memory correlated with speech and language severity. Compared to NoND children, a weak, significant reduction in fractional anisotropy (FA) in the left presupplementary motor area (preSMA) FAT component was found. Only speech severity correlated and predicted FA values along with the FAT in both of its components, and visual-spatial working memory moderated the relationship between speech severity and FA in the left SMA. Our study supports the conceptualization of a composite and complex picture of CAS, not limited to the speech core deficit, but also involving high-order cognitive skills. [ABSTRACT FROM AUTHOR]

Surgery-related strokes are an important cause of morbidity following resection of high-grade glioma (HGG). We explored the incidence, risk factors and clinical consequences of intra-operative ischemic strokes in surgeries for resection of HGG. We retrospectively followed a cohort of 239 patients who underwent surgical resection of HGG between 2013 and 2017. Tumor types included both isocitrate dehydrogenase (IDH) wildtype glioblastoma and IDH-mutant WHO grade 4 astrocytoma. We analyzed pre- and post-operative demographic, clinical, radiological, anesthesiology and intraoperative neurophysiology data, including overall survival and functional outcomes. Acute ischemic strokes were seen on postoperative diffusion-weighted imaging (DWI) in 30 patients (12.5%), 13 of whom (43%) developed new neurological deficits. Infarcts were more common in insular (23%, p = 0.019) and temporal surgeries (57%, p = 0.01). Immediately after surgery, 35% of patients without infarcts and 57% of those with infarcts experienced motor deficits (p = 0.022). Six months later, rates of motor deficits decreased to 25% in the non-infarcts group and 37% in the infarcts group (p = 0.023 and 0.105, respectively) with a significantly lower Karnofsky-Performance Score (KPS, p = 0.001). Intra-operative language decline in awake procedures was a significant indicator of the occurrence of intra-operative stroke (p = 0.029). In conclusion, intraoperative ischemic events are more common in insular and temporal surgeries for resection of HGG and their intra-operative detection is limited. These strokes can impair motor and speech functions as well as patients' performance status. [ABSTRACT FROM AUTHOR]

Objective: To report our experience and investigate frequencies of adverse events and functional status from the first 5 years of performing awake surgery for gliomas in a single-center population-based setting. Methods: We conducted a review of all patients with a glioma treated with awake surgery during the first 5 years following introduction of awake surgery at our center (February 2015 to February 2020). We assessed functional and radiological outcome, with adverse events classified according to the Landriel-Ibanez classification for neurosurgical complications, while neurological deficits were further subdivided into transient vs permanent. We sought to analyze our initial results and learning curve, as well as compare our results with literature. Results: Forty-two patients were included. The median age was 38 years (range 18–66) and 13 (31%) were female. The indication for awake surgery was a presumed glioma in or near an eloquent area. The overall 30-day complication rate was 25 (59%), with 19 (45%) grade I complications, 3 (7%) grade II complications, and 3 (7%) grade III complications. Fifteen patients (36%) experienced transient neurological deficits, and 11 (26%) permanent neurological deficits. At 3-month follow-up, the Karnofsky Performance Score was 80 or higher for the entire cohort. The median extent of resection was 87%, with GTR achieved in 11 (26%). In search of potential learning curve difficulties, patients were divided into the 21 patients treated first (Early Group) versus the remaining 21 patients treated later (Late Group); no statistically significant difference in operating time, amount of tumor removed, or incidence of long-term postoperative neurological deficit was identified between groups. No awake surgery was aborted due to seizures. Comparison to the literature was limited by the diverse and unsystematic way in which previous studies have reported adverse events after awake craniotomy for gliomas. Conclusion: We provide a standardized report of adverse events and functional status following awake surgery for glioma during a single-center 5-year learning period, with similar rates of severe adverse events and functional outcome compared to literature without concerns of substantial learning curve difficulties. However, this comparison was flawed by non-standardized reporting of complications, highlighting a demand for more standardized reporting of adverse events after awake craniotomies. [ABSTRACT FROM AUTHOR]

Chordomas are rare malignant neoplasms, accounting for 1–4% of all primary bone tumors. Most spinal chordomas occur in the sacrococcygeal region and the base of the skull; however, 6% of chordomas are observed in the cervical spine. In these cases, the lesion is mainly located in the midline. These tumors slowly grow before becoming symptomatic and encase the surrounding vascular and nerve structures. Patients with advanced chordoma have a poor prognosis due to local recurrence with infiltration and destruction of adjacent bone and tissues. Systemic chemotherapy options have not been fully effective in these tumors, especially for recurrent chordomas. Thus, new combinations of currently available targeted molecular and biological therapies with radiotherapy have been proposed as potential treatment modalities. Here, the present paper describes the case of a 41-year-old male with a C2–C4 chordoma located paravertebrally, who underwent surgical resection with a debulking procedure for a cervical chordoma. Computed tomography angiography revealed a paraspinal mass with bone remodeling and the MRI showed a paravertebral mass penetrating to the spinal canal with a widening of the intervertebral C2–C3 foramen. Initially, the tumor was diagnosed as schwannoma based on its localization and imaging features; however, the histopathology specimen confirmed the diagnosis of chordoma. This case study highlights the effectivity of radical surgical resection as a mainstay treatment for chordomas, discusses neuroimaging, diagnosis, and the use of currently available targeted therapies and forthcoming treatment strategies, as alternative treatment options for chordoma. [ABSTRACT FROM AUTHOR]

Background: Neurological disorders are a major source of suffering for patients worldwide. Scalp stimulation methods have been widely applied in treating a number of neurological disorders. Recently, our understanding of pathological mechanisms associated with neurological disorders has been enhanced significantly. Nevertheless, these findings have yet to be well-integrated into scalp stimulation treatments for neurological disorders. Methods: In a previous study, we proposed new brain targets for scalp stimulation in the treatment of eight common mental disorders based on the results of a large-scale meta-analyses using Neurosynth. This study aims to extend our previous findings in identifying surface brain targets for seven common neurological disorders: Alzheimer’s disease, aphasia, chronic pain, dementia, dyslexia, mild cognitive impairment, and Parkinson’s disease, utilizing a similar method. Results: We hidentified seven to eight potential scalp stimulation targets for each disorder and used both 10–20 EEG system and acupuncture points to locate these targets to facilitate its clinical application. Conclusions: The proposed target protocols may facilitate and extend clinical applications of scalp stimulation methods such as transcranial electrical stimulation and scalp acupuncture in the treatment of neurological disorders. [ABSTRACT FROM AUTHOR]

To review the diagnostic accuracy and possible added value of Brainstem Auditory Evoked Potentials (BAEP) monitoring and Lateral Spread Response (LSR) monitoring in microvascular decompression surgery for hemifacial spasms. For this systematic review we followed the PRISMA guidelines. We searched different databases and bibliographies of articles. We included studies on BAEP and LSR monitoring that reported data on hearing outcome or efficacy. Selected studies were assessed for bias using the MINORS tool. 64 articles were selected for qualitative synthesis, 42 met inclusion criteria for meta-analysis. The overall incidence of hearing loss was 3.4%. For BAEP monitoring AUC and pooled OR with 95% confidence interval were 0.911 (0.753–0.933) and 7.99 (3.85–16.60) respectively. Short-term data on LSR monitoring showed an overall spasm relief rate of 89% with pooled OR, sensitivity and specificity with a 95% confidence interval of 8.80 (4.82–16.08), 0.911 (0.863–0.943) and 0.451 (0.342–0.564) respectively. Long-term data on LSR monitoring showed an overall spasm relief rate of 95% with pooled OR, sensitivity and specificity with a 95% confidence interval of 4.06 (2.15–7.64), 0.871 (0.817–0.911) and 0.39 (0.294–0.495) respectively. The alarm criteria, a wave V latency prolongation of 1ms or a wave V amplitude decrement of 50%, proposed by the 'American Clinical Neurophysiology Society' are a sensitive predictor for postoperative hearing loss. Other BAEP wave changes, for example, complete loss of wave V, are more specific but correspond to irreversible damage and are therefore not useful as warning criteria. LSR monitoring has high diagnostic accuracy at short-term follow-up. At long-term follow-up, diagnostic accuracy decreases because most patients get spasm relief regardless of their LSR status. LSR persistence after surgery has a good long-term outcome, as long as an extensive exploration of the facial nerve has been performed. [ABSTRACT FROM AUTHOR]

The lateral spread response (LSR) on preoperative facial electromyogram (EMG) is a useful tool in evaluating patients with hemifacial spasm (HFS). There may be some instances where the LSR does not appear on the preoperative EMG, thus disrupting the diagnosis and treatment of HFS. In this study, we evaluated the patients who did not exhibit LSR on preoperative EMG but underwent microvascular decompression (MVD) for hemifacial spasm. We searched for patients who underwent MVD for HFS but had an absence of LSR on preoperative EMG between January 2016 and June 2018. Surgical outcomes were evaluated at 1, 3, and 6 months after surgery. Follow-up facial EMG was performed 3 months after surgery. Results were divided into two categories: (1) spasm relief within 24 h of surgery and (2) spasm was observed immediately post-operation. The following parameters were analyzed when comparing between the two groups: age, sex, affected side, duration of symptoms, and offending vessel(s). A total of 306 patients underwent MVD for HFS during the study period. Among them, 13 (4.2%) patients had no LSR on preoperative EMG. Eight patients (61.5%) were female and five patients were male. The 13 patients had a mean age of 51 years. All patients exhibited probable offending vessels in the root exit zone (REZ) of the facial nerve on preoperative magnetic resonance (MR) imaging that was confirmed during surgery. Seven patients were free of HFS immediately after surgery, though six patients were not. Only one (7.7%) patient had persisted symptom 6 months after surgery. No patients experienced recurrence of spasm, nor exhibited abnormal waves on follow-up facial EMG. LSR on facial EMG is a valuable tool for evaluating hemifacial spasm. However, although LSR did not appear on preoperative EMG, if the patient presents with typical symptoms and the offending vessels are identified on MRI, we expect good results after MVD for HFS. [ABSTRACT FROM AUTHOR]

Objective: To analyze the efficacy and complications of microvascular decompression for hemifacial spasm.Study Design: Retrospective study.Setting: Regional hospital.Methods: Fifty-five patients with hemifacial spasm were treated by microvascular decompression. All patients with hemifacial spasm who underwent retrosigmoid microvascular decompression from May 2004 to January 2017 were included. Patients with no conflict on preoperative magnetic resonance imaging or with an alternate diagnosis were excluded.Results: The overall cure rate was 83.64%, with an average follow-up of 7.4 years. A left-sided hemifacial spasm was a healing-promoting factor (P = .01). The median healing was 0.03 months, and the mean was 6 months. The efficacy remained high in the medium term (88% at 3 years), long term (90.24% at 5 years), and very long term (90.48% at 8 years). The recurrence rate was 9.8%. Favorable criteria included a right-sided spasm (P = .01) and an average age of 62 years (P = .03). The specific complications were permanent facial palsy (3.63%), unilateral deafness (5.45%), and hearing loss (3.63%). No death was reported. Regarding the quality of life of the patients, 94.7% had a modified HFS-8 postoperative score of 0 (Hemifacial Spasm 8 Quality of Life Scale).Conclusion: Microvascular decompression for hemifacial spasm is an effective and lasting technique. Its low rate of complications and the considerable quality-of-life improvement should lead surgeons to propose it to patients as soon as botulinum toxin injections become ineffective or poorly tolerated. [ABSTRACT FROM AUTHOR]

Background: Research suggests that unconscious activity in the supplementary motor area (SMA) precedes not only certain simple motor actions but also the point at which we become aware of our intention to perform such actions. The extent to which these findings have implications for our understanding of the concepts of free will and personal responsibility has been subject of intense debate during the latest four decades. Methods: This research is discussed in relation to effects of neurosurgical removal of the SMA in a narrative review. Results: Removal of the SMA typically causes a transient inability to perform non-stimulus-driven, voluntary actions. This condition, known as the SMA syndrome, does not appear to be associated with a loss of sense of volition but with a profound disruption of executive function/cognitive control. Conclusions: The role of the SMA may be to serve as a gateway between the corticospinal tract and systems for executive function. Such systems are typically seen as tools for conscious decisions. What is known about effects of SMA resections would thus seem to suggest a view that is compatible with concepts of personal responsibility. However, the philosophical question whether free will exists cannot be definitely resolved on the basis of these observations. [ABSTRACT FROM AUTHOR]

Although studies have indicated that the small posterior fossa plays a role in hemifacial spasm (HFS), few studies have denoted the correlations between local measurements of the cerebellopontine angle and the incidence of HFS and surgical outcomes. We retrospectively analyzed the demographic and clinical data of HSF patients who underwent microvascular decompression at our institution. Healthy controls were recruited. The divergent prognosis of HFS was defined as an ordinal variable. A multivariable ordinal regression model was generated to estimate the relationship between the variables and outcomes of HFS. Between 2013 and 2018, 180 patients who were enrolled in our study met the inclusion criteria. Compared with the control group (n = 94), HFS patients had a smaller internal acousticmeatus-brainstem distance (P < 0.001) on the unaffected side and a larger facial nerve-brainstem angle (P < 0.001). The regression analysis demonstrated that subgroups with more severe facial nerve compression (mild vs severe, OR = 0.269, P = 0.018; moderate vs severe, OR = 0.215, P < 0.001) and a thinner brainstem (OR = 2.368, P = 0.014) were more likely to experience better short-term outcomes, while subgroups with a thinner brainstem (OR = 5.583, P = 0.007) were more likely to experience better long-term outcomes. Structural changes occurring in patients are risk factors for HFS. The patient's local neurovascular structure and brainstem volume are factors that significantly influence short-term and long-term surgical outcomes. [ABSTRACT FROM AUTHOR]

Developmental venous anomalies (DVAs), previously also known as venous angiomas, are variations of normal trans-medullary veins draining from white and gray matter. DVAs are usually asymptomatic and mostly discovered incidentally on brain imaging. However, some studies have reported symptomatic cases associated with DVAs. In this report, we report an extremely rare case of a 14-month-old boy with obstructive hydrocephalus following aqueductal stenosis caused by developmental venous anomalies. At the age of 14 months, his head circumference exceeded + 2SD significantly. Brain magnetic resonance imaging (MRI) showed triventriculomegaly and dilated collector vein coursing through the Sylvian aqueduct, causing aqueductal stenosis. Endoscopic third ventriculostomy (ETV) was successfully performed. During the procedure, a dilated collector vein was confirmed obstructing the Sylvian aqueduct. Postoperative cine MRI showed good flow signal through the opening and improvement of hydrocephalus was noted. Obstructive hydrocephalus following aqueductal stenosis caused by DVAs is very rare; nonetheless, it can be considered as a causal differential diagnosis for hydrocephalus. Whether ETV should be chosen, as the technique for diversion of cerebrospinal fluid (CSF) flow, remains controversial. This case report showed that ETV was effective and safe. [ABSTRACT FROM AUTHOR]

Differences between males and females in brain development and in the organization and hemispheric lateralization of brain functions have been described, including in language. Sex differences in language organization may have important implications for language mapping performed to assess, and minimize neurosurgical risk to, language function. This study examined the effect of sex on the activation and functional connectivity of the brain, measured with presurgical functional magnetic resonance imaging (fMRI) language mapping in patients with a brain tumor. We carried out a retrospective analysis of data from neurosurgical patients treated at our institution who met the criteria of pathological diagnosis (malignant brain tumor), tumor location (left hemisphere), and fMRI paradigms [sentence completion (SC); antonym generation (AG); and resting-state fMRI (rs-fMRI)]. Forty-seven patients (22 females, mean age = 56.0 years) were included in the study. Across the SC and AG tasks, females relative to males showed greater activation in limited areas, including the left inferior frontal gyrus classically associated with language. In contrast, males relative to females showed greater activation in extended areas beyond the classic language network, including the supplementary motor area (SMA) and precentral gyrus. The rs-fMRI functional connectivity of the left SMA in the females was stronger with inferior temporal pole (TP) areas, and in the males with several midline areas. The findings are overall consistent with theories of greater reliance on specialized language areas in females relative to males, and generalized brain areas in males relative to females, for language function. Importantly, the findings suggest that sex could affect fMRI language mapping. Thus, considering sex as a variable in presurgical language mapping merits further investigation. [ABSTRACT FROM AUTHOR]

The supplementary motor area (SMA) syndrome is characterized by transient weakness and akinesia contralateral to the side of the affected hemisphere. The underlying pathology of the syndrome is not fully understood but is thought to be related to lesions in the SMA, residing principally in the mesial superior frontal gyrus (Broadmann's area 6c). Although the SMA syndrome a well-characterized clinical entity, we report herein, to our knowledge, the first case of isolated lower extremity SMA syndrome in the literature. This case highlights the importance of considering this rare clinical entity in the context of new or worsening postoperative neurologic deficits. Moreover, early studies did not support somatotopic organization of the SMA as in the primary motor cortex; emerging evidence suggests that delicate somatotopic representation may underlie distinct presentations like that reported in the present case. [ABSTRACT FROM AUTHOR]

Majority of movements in everyday situations are complex and involve volition, planning of the movement and selection of the motor programme, all occurring before movement execution. Higher order motor disorders may be defined as abnormal motor behaviours resulting from disruption of any of the cortical processes that precede execution of the motor act. They are common in patients with neurodegenerative disorders, psychiatric diseases and structural brain lesions. These abnormal behaviours may be overlooked in the clinic, unless specifically evoked by the examiner. We discuss clinical and pathophysiological aspects of higher order motor disorders including: (1) disorders of disinhibition, such as grasp reflex and grasping behaviour, utilisation and imitation behaviour, motor preservations and paratonia; (2) disorders of motor intention such as motor neglect and motor impersistence; (3) alien limb syndrome; and (4) motor overflow phenomena, such as mirror movements and synkinesias. A video illustration of each phenomenon is provided. We place the findings from recent neurophysiological studies within the framework of theories of motor control to provide better insight into pathophysiology of different disorders. [ABSTRACT FROM AUTHOR]

Background: The preoperative evaluation of drug-resistant focal epilepsy patients considered for epilepsy surgery provides a unique setting to evaluate cortical function and corresponding networks. Aims: Whereas there is a wealth of data on cortical language localization using electrical stimulation with subdural electrodes, there is much less experience with stimulation of depth electrodes in the white matter and an effect on language function via electric stimulation of the corpus callosum has not been demonstrated so far. Methods & Procedures: We report on a 29-year-old epilepsy patient with bilateral language representation who underwent pre-surgical EEG-video-monitoring for drug-resistant, non-lesional right frontal lobe epilepsy. Outcomes & Results: Electric stimulation of a stereotactically implanted depth electrode in the right anterior corpus callosum elicited paraphasia and anomia. The precise mechanism could be an inhibition of cortical language areas in the left hemisphere, the right hemisphere or interference with transcallosal connectivity. Conclusions: This is the first report on language dysfunction through electric stimulation in the corpus callosum, most likely through an inhibition of cortical language areas in the left frontal lobe. [ABSTRACT FROM AUTHOR]

The Supplementary Motor Area (SMA)—located in the superior and medial aspects of the superior frontal gyrus—is a preferential site of certain brain tumors and arteriovenous malformations, which often provoke the so-called SMA syndrome. The bulk of the literature studying this syndrome has focused on two of its most apparent symptoms: contralateral motor and speech deficits. Surprisingly, little attention has been given to working memory (WM) even though neuroimaging studies have implicated the SMA in this cognitive process. Given its relevance for higher-order functions, our main goal was to examine whether WM is compromised in SMA lesions. We also asked whether WM deficits might be reducible to processing speed (PS) difficulties. Given the connectivity of the SMA with prefrontal regions related to executive control (EC), as a secondary goal we examined whether SMA lesions also hampered EC. To this end, we tested 12 patients with lesions involving the left (i.e., the dominant) SMA. We also tested 12 healthy controls matched with patients for socio-demographic variables. To ensure that the results of this study can be easily transferred and implemented in clinical practice, we used widely-known clinical neuropsychological tests: WM and PS were measured with their respective Wechsler Adult Intelligence Scale indexes, and EC was tested with phonemic and semantic verbal fluency tasks. Non-parametric statistical methods revealed that patients showed deficits in the executive component of WM: they were able to sustain information temporarily but not to mentally manipulate this information. Such WM deficits were not subject to patients’ marginal PS impairment. Patients also showed reduced phonemic fluency, which disappeared after controlling for the influence of WM. This observation suggests that SMA damage does not seem to affect cognitive processes engaged by verbal fluency other than WM. In conclusion, WM impairment needs to be considered as part of the SMA syndrome. These findings represent the first evidence about the cognitive consequences (other than language) of damage to the SMA. Further research is needed to establish a more specific profile of WM impairment in SMA patients and determine the consequences of SMA damage for other cognitive functions. [ABSTRACT FROM AUTHOR]