Glioblastomas at the white matter of temporo-parietal junction cause a poor postoperative independence level.

INTRODUCTION: Right cerebral hemispheric glioblastomas (GBMs) often decrease the Karnofsky performance status (KPS) score postoperatively, despite the patient having sufficient patient function while performing daily living. This study aimed to evaluate the factors that could cause poor KPS scores during the postoperative chronic phase in patients with right cerebral hemispheric GBMs. METHODS: Data of 47 patients with newly diagnosed right cerebral hemispheric GBMs were analyzed. All patients were assessed preoperatively and 3 months postoperatively to determine KPS and brain function. To determine tumor location related to the postoperative KPS scores, we used voxel-based lesion symptom mapping (VLSM). The patients were divided into two groups (involvement and non-involvement groups) based on whether their lesion involved a significant region identified by VLSM. We then compared functional factors and prognosis between the groups using the chi-squared and log-rank tests, respectively. RESULTS: The KPS score significantly decreased after surgery compared to that preoperatively measured (p = 0.023). VLSM revealed that tumors in the white matter of temporo-parietal junction (WM-TPJ) caused a significant decline in the KPS score at three months postoperatively. The patients in the involvement group had a higher probability of impaired attention, visuospatial cognition, emotion recognition, and visual field than did those in the non-involvement group. In addition, tumor in the WM-TPJ were associated with shorter progression-free survival and overall survival (p = 0.039 and 0.023, respectively). CONCLUSIONS: GBMs involving the right WM-TPJ are more likely to result in poor postoperative KPS scores and prognoses. Impairments of several kinds of brain functions caused by tumor invasion to the WM-TPJ may be associated with lower KPS scores.

Posterior-prefrontal and medial orbitofrontal regions play crucial roles in happiness and sadness recognition.

The core brain regions responsible for basic human emotions are not yet fully understood. We investigated the key areas responsible for emotion recognition of facial expressions of happiness and sadness using data obtained from patients who underwent local brain resection. A total of 44 patients with right cerebral hemispheric brain tumors and 33 healthy volunteers were enrolled and subjected to a facial expression recognition test. Voxel-based lesion-symptom mapping was performed to investigate the relationship between the accuracy of emotion recognition and the resected regions. Consequently, trade-off relationships were discovered: the posterior-prefrontal region was related to a low score of happiness recognition and a high score of sadness recognition (disorder-of-happiness group), whereas the medial orbitofrontal region was related to a low score of sadness recognition and a high score of happiness recognition (disorder-of-sadness group). The emotion recognition score in both the happiness and sadness disorder groups was significantly lower than that in the control group (p = 0.0009 and p = 0.021, respectively). Interestingly, the deficit in happiness recognition was temporary, whereas the deficit in sadness recognition persisted during the chronic phase. Using graph theoretical analysis, we identified structural connectivity between the posterior-prefrontal and medial orbitofrontal regions. When either of these regions was damaged, the tract volume connecting them was significantly reduced (p = 0.013). These results indicate that the posterior-prefrontal and medial orbitofrontal regions may be crucial for maintaining a balance between happiness and sadness recognition in humans. Investigating the clinical impact of certain area resections using lesion studies combined with connectivity analysis is a useful neuroimaging method for understanding neural networks.

Two different subcortical language networks supporting distinct Japanese orthographies: morphograms and phonograms.

Language systems worldwide are based on either morphograms or phonograms, but Japanese is unique in that uses a complicated combination of kanji (morphogram) and kana (phonogram) characters. The white matter networks associated with reading have been investigated previously but remain incompletely understood. In this study, we performed intraoperative language mapping under local anesthesia and postoperative language assessments of 53 consecutive patients who underwent awake craniotomy for surgical resection of cerebral glioma within the dominant temporal or parietal lobe. Six cases showing intraoperative dyslexia elicited by direct electrical stimulation (DES) were examined, and all cases showed transient symptoms of kanji or kana dyslexia during DES. We investigated the intraoperative positive mapping points localized near four white matter bundles: the arcuate fascicle, posterior superior longitudinal fascicle, inferior fronto-occipital longitudinal fascicle, and inferior longitudinal fascicle (ILF). The intraoperative DES distributions for kanji dyslexia were especially associated with the anterior-inferior side of the ILF. On the other hand, the DES points associated with kana dyslexia were localized on the posterior-superior side of the complex composed of these four tracts. These results suggest the presence of specific non-interfering networks that subserve the processes of reading morphograms and phonograms.

Quality of life following awake surgery depends on ability of executive function, verbal fluency, and movement.

INTRODUCTION: The outcome of awake surgery has been evaluated based on functional factors, return to work, and oncological aspects, and there have been no reports directly examining QOL. This study aimed to investigate the outcome of QOL following awake surgery and to determine the functional factors influencing QOL. METHODS: Seventy patients with WHO grade II/III gliomas were included. For the assessment of QOL, we used the SF-36 and calculated summary and sub-component scores. Three summary component scores, including physical (PCS), mental (MCS), and role/social summary (RCS) component scores, were computed based on sub-component scores. Additionally, various assessments of neurological/neuropsychological function were performed. We performed univariate and multiple regression analyses to investigate the functional factors influencing the SF-36. RESULTS: PCS and MCS were maintained, but only RCS was low to 42.0 ± 16.1. We then focused on the RCS and its sub-components: general health (GH), role physical (RP), social functioning (SF), and role emotional (RE). Multiple regression analysis showed following significant correlations between the sub-component scores and brain functions: GH to executive function and movement (p = 0.0033 and 0.032), RP to verbal fluency and movement (p = 0.0057 and 0.0010), and RE to verbal fluency (p = 0.020). Furthermore, when the sub-component scores were compared between groups with and without functional deficits related to GH, RP, and RE, each score was significantly lower in the groups with functional deficits (p = 0.012, 0.014, and 0.0049, respectively). CONCLUSIONS: In patients who underwent awake surgery, a subset of patients had low QOL because of poor RCS. Functional factors influencing QOL included executive function, verbal fluency, and movement.

Disconnection of posterior part of the frontal aslant tract causes acute phase motor functional deficit.

The frontal aslant tract (FAT) mainly connects the supplementary motor area (SMA) and inferior frontal gyrus. The left FAT is involved in language-related functions, while the functional role of the right FAT is not fully understood. The aim of this study was to investigate the function of the right FAT by dividing it into three segments according to the anatomical structure. A total of 34 right frontal gliomas who had undergone surgery were studied. Participants were assessed for the acute and chronic phases of several neuropsychological and motor functions. FAT was reconstructed into the anterior, middle, and posterior segments according to the cortical connections as the medial prefrontal cortex, pre-SMA, and SMA proper, respectively. The relationships between the damaged severity of each FAT segment and behavioral scores were analyzed. A significant relationship was observed only in the acute phase motor function and posterior segment of the FAT. The middle segment was involved in motor function, but it did not have a sufficient significance level compared to the posterior segment. Our study revealed that the right FAT can be divided into three segments and that its posterior segment is related to acute phase motor function.

Preserving Right Pre-motor and Posterior Prefrontal Cortices Contribute to Maintaining Overall Basic Emotion.

Basic emotions such as happiness, sadness, and anger are universal, regardless of the human species, and are governed by specific brain regions. A recent report revealed that mentalizing, which is the ability to estimate other individuals' emotional states via facial expressions, can be preserved with the help of awake surgery. However, it is still questionable whether we can maintain the ability to understand others' emotions by preserving the positive mapping sites of intraoperative assessment. Here, we demonstrated the cortical regions related to basic emotions via awake surgery for patients with frontal glioma and investigated the usefulness of functional mapping in preserving basic emotion. Of the 56 consecutive patients with right cerebral hemispheric glioma who underwent awake surgery at our hospital, intraoperative assessment of basic emotion could be successfully performed in 22 patients with frontal glioma and were included in our study. During surgery, positive responses were found in 18 points in 12 patients (54.5%). Of these, 15 points from 11 patients were found at the cortical level, mainly the premotor and posterior part of the prefrontal cortices. Then, we focused on cortical 15 positive mappings with 40 stimulations and investigated the types of emotions that showed errors by every stimulation. There was no specific rule for the region-emotional type, which was beyond our expectations. In the postoperative acute phase, the test score of basic emotion declined in nine patients, and of these, it decreased under the cut-off value (Z-score ≤ -1.65) in three patients. Although the total score declined significantly just after surgery (p = 0.022), it recovered within 3 months postoperatively. Our study revealed that through direct electrical stimulation (DES), the premotor and posterior parts of the prefrontal cortices are related to various kinds of basic emotion, but not a single one. When the region with a positive mapping site is preserved during operation, basic emotion function might be maintained although it declines transiently after surgery.

Awake surgery for right frontal lobe glioma can preserve visuospatial cognition and spatial working memory.

PURPOSE: Awake surgery is the standard treatment to preserve motor and language functions. This longitudinal study aimed to evaluate the resection rate and preservation of neurocognitive functions in patients with right frontal lobe glioma who underwent awake surgery. METHODS: Thirty-three patients (mean age, 48.0 years) with right frontal lobe glioma who underwent awake surgery at our hospital between 2013 and 2019 were included. Fourteen, thirteen, and six cases had WHO classification grades of II, III, and IV, respectively. We evaluated visuospatial cognition (VSC) and spatial working memory (SWM) before and three months after surgery. Relevant brain areas for VSC and SWM were intraoperatively mapped, whenever the task was successfully accomplished. Therefore, patients were divided into an intraoperative evaluation group and a non-evaluation group for each function, and the resection rate and functional outcomes were compared. RESULTS: The removal rate in the evaluation group for VSC and SWM were similar to that in the non-evaluation group. Chronic impairment rate of VSC was significantly lower in the evaluation than in the non-evaluation group (5.6% vs. 33.3%, p = 0.034). No patient showed postoperative SWM impairment in the evaluation group as opposed to the non-evaluation group (16.7%, p = 0.049). The probability of resection of the deeper posterior part of the middle frontal gyrus, the relevant area of VSC, was higher in the non-evaluation group than in the evaluation group. CONCLUSIONS: We statistically verified that awake surgery for right frontal lobe glioma results in successful preservation of VSC and SWM with satisfying resection rates.

Glioma surgery under awake condition can lead to good independence and functional outcome excluding deep sensation and visuospatial cognition.

BACKGROUND: Awake surgery for the eloquent cortex is a common strategy for glioma surgery. Although a recent emphasis has been placed on awake surgery both for dominant and nondominant cerebral hemispheres to preserve neurological/neuropsychological functions, those functional outcomes are not well investigated because few studies have focused on the longitudinal recovery process. This study explored the outcome of neurological/neuropsychological functions following awake surgery until the chronic phase. METHODS: A total of 87 patients with glioma who underwent awake surgery were included, and of these 66 patients matched our inclusion criteria. Each patient was assessed for neurological/neuropsychological functions before surgery, as well as acute and chronic phase. Additionally, scores for the KPS were collected. RESULTS: Almost all functions recovered within 3 months postoperatively, even when transient deficits were observed in the acute phase; however, deep sensory perception deficits and visuospatial cognitive disorders persisted into the chronic phase (15.4% of patients with parietal lesions, 14.3% of patients with right cerebral hemispheric lesion, respectively). KPS score ≥90 was achieved in 86.0% of patients with lower-grade glioma, whereas only 52.2% of glioblastoma patients scored ≥90. Primary causes of declined KPS were disorder of visuospatial cognition, sensorimotor function including deep sensation, aphasia, and emotional function. CONCLUSIONS: Awake surgery leads to good functional outcome at the chronic phase of neurological/neuropsychological functions, except for deep sensory and visuospatial cognition. Because sensation and visuospatial cognitive disorder have major impacts on patients' independence level, further importance should be placed on preserving these functions during surgery.

Awake surgery for glioblastoma can preserve independence level, but is dependent on age and the preoperative condition.

PURPOSE: Lately, awake surgery has been frequently adapted for glioblastoma (GBM). However, even with awake surgery, the expected long-term independence levels may not be achieved. We studied the characteristics of independence levels in GBM patients, and investigated the usefulness and parameter thresholds of awake surgery from the standpoint of functional outcomes. METHODS: Totally, 60 GBM patients (awake group, n = 30; general anesthesia group, n = 30) who underwent tumor resection surgery were included. We collected preoperative and 1- and 3-month postoperative Karnofsky Performance Status (KPS) scores, and analyzed causes of low KPS scores from the aspect of function, brain region, and clinical factors. Then, we focused on the operative method, and investigated the usefulness of awake surgery. Finally, we explored the parameter standards of awake surgery in GBM considering independence levels. RESULTS: Postoperative KPS were significantly lower than preoperative scores. Responsible lesions for low KPS scores were deep part of the left superior temporal gyrus and the right posterior temporal gyri that may be causes of aphasia and neuropsychological dysfunctions, respectively. Additionally, operative methods influenced on low independence level; long-term KPS scores in the awake group were significantly higher than those in the general anesthesia group, but they depended on age and preoperative KPS scores. Receiver operating characteristic curve analysis showed preoperative KPS = 90 and age = 62 years as the cutoff values for preservation of long-term KPS scores in awake group. CONCLUSION: Awake surgery for GBM is useful for preserving long-term independence levels, but outcomes differ depending on age and preoperative KPS scores.

Neural Networks Mediating High-Level Mentalizing in Patients With Right Cerebral Hemispheric Gliomas.

Mentalizing is the ability to understand others' mental state through external cues. It consists of two networks, namely low-level and high-level metalizing. Although it is an essential function in our daily social life, surgical resection of right cerebral hemisphere disturbs mentalizing processing with high possibility. In the past, little was known about the white matter related to high-level mentalizing, and the conservation of high-level mentalizing during surgery has not been a focus of attention. Therefore, the main purpose of this study was to examine the neural networks underlying high-level mentalizing and then, secondarily, investigate the usefulness of awake surgery in preserving the mentalizing network. A total of 20 patients with glioma localized in the right hemisphere who underwent awake surgery participated in this study. All patients were assigned to two groups: with or without intraoperative assessment of high-level mentalizing. Their high-level mentalizing abilities were assessed before surgery and 1 week and 3 months after surgery. At 3 months after surgery, only patients who received the intraoperative high-level mentalizing test showed the same score as normal healthy volunteers. The tract-based lesion symptom analysis was performed to confirm the severity of damage of associated fibers and high-level mentalizing accuracy. This analysis revealed the superior longitudinal fascicles (SLF) III and fronto-striatal tract (FST) to be associated with high-level mentalizing processing. Moreover, the voxel-based lesion symptom analysis demonstrated that resection of orbito-frontal cortex (OFC) causes persistent mentalizing dysfunction. Our study indicates that damage of the OFC and structural connectivity of the SLF and FST causes the disorder of mentalizing after surgery, and assessing high-level mentalizing during surgery may be useful to preserve these pathways.

Damage of the right dorsal superior longitudinal fascicle by awake surgery for glioma causes persistent visuospatial dysfunction.

Patients with glioma frequently present with neuropsychological deficits preoperatively and/or postoperatively, and these deficits may remain after the chronic phase. However, little is known about postoperative recovery course of right hemispheric function. We therefore studied the characteristics and causes of persistent cognitive dysfunction in right cerebral hemispheric glioma. Eighteen patients who underwent awake surgery participated in this study. All patients who received preoperative neuropsychological examinations were assigned to two groups according to their test results: preoperative deficit and normal. They were reassessed 1 week and 3 months after surgery. The rates of remaining deficits in the deficit group at chronic phase were higher than those of the normal group for all functions. Despite preoperative normal function, the remaining rate for visuospatial cognitive deficits was the highest among all functions. The voxel-based lesion-symptom mapping analysis for visuospatial cognition revealed that a part of the medial superior and middle frontal gyri were resected with high probability in patients with low visuospatial cognitive accuracy. Our study indicates that in patients with preoperative neuropsychological deficits, these deficits tend to remain until the chronic phase. Visuospatial dysfunction frequently persists until the chronic phase, which might reflect damage to the superior longitudinal fasciclus I and II.

Oropharyngeal Dysphagia in Dermatomyositis: Associations with Clinical and Laboratory Features Including Autoantibodies.

OBJECTIVE: Dysphagia develops with low frequency in patients with dermatomyositis. Our objective was to determine the clinical and laboratory features that can estimate the development of dysphagia in dermatomyositis. METHODS: This study included 92 Japanese patients with adult-onset dermatomyositis. The associations between dysphagia and clinical and laboratory features including disease-specific autoantibodies determined by immunoprecipitation assays were analyzed. RESULTS: Videofluoroscopy swallow study (VFSS) was performed for all patients with clinical dysphagia (n = 13, 14.1%) but not for patients without clinical dysphagia. Typical findings of dysphagia (pharyngeal pooling, n = 11 and/or nasal regurgitation, n = 4) was detected by VFSS in all patients with clinical dysphagia. Eleven patients with dysphagia (84.6%) had anti-transcription intermediary factor 1γ (TIF-1γ) antibody. By univariate analysis, the average age and the male to female ratio, internal malignancy, and anti-TIF-1γ antibody were significantly higher and the frequency of interstitial lung diseases and manual muscle testing (MMT) scores of sternomastoid and dertoid muscles were significantly lower in patients with dysphagia than in patients without dysphagia. Among patients with anti-TIF-1γ antibody, the mean age, the ratios of male to female and internal malignancy were significantly higher and mean MMT scores of sternomastoid muscle were significantly lower in patients with dysphagia compared with patients without dysphagia. By multivariable analysis, the risk of dysphagia was strongly associated with the existence of internal malignancy and ant-TIF-1γ antibody and was also associated with reduced scores of manual muscle test of sternomastoid muscle. Dysphagia was markedly improved after the treatment against myositis in all 13 patients. CONCLUSION: These findings indicate that dysphagia can develop frequently in patients with internal malignancy, anti-TIF-1γ antibody, or severe muscle weakness of sternomastoid muscle.

Chronic spatial working memory deficit associated with the superior longitudinal fasciculus: a study using voxel-based lesion-symptom mapping and intraoperative direct stimulation in right prefrontal glioma surgery.

OBJECTIVE Although the right prefrontal region is regarded as a silent area, chronic deficits of the executive function, including working memory (WM), could occur after resection of a right prefrontal glioma. This may be overlooked by postoperative standard examinations, and the disabilities could affect the patient's professional life. The right prefrontal region is a part of the frontoparietal network and is subserved by the superior longitudinal fasciculus (SLF); however, the role of the SLF in spatial WM is unclear. This study investigated a persistent spatial WM deficit in patients who underwent right prefrontal glioma resection, and evaluated the relationship between the spatial WM deficit and the SLF. METHODS Spatial WM was examined in 24 patients who underwent prefrontal glioma resection (right, n = 14; left, n = 10) and in 14 healthy volunteers using a spatial 2-back task during the long-term postoperative period. The neural correlates of spatial WM were evaluated using lesion mapping and voxel-based lesion-symptom mapping. In addition, the spatial 2-back task was performed during surgery under direct subcortical electrical stimulation in 2 patients with right prefrontal gliomas. RESULTS Patients with a right prefrontal lesion had a significant chronic spatial WM deficit. Voxel-based lesion-symptom mapping analysis revealed a significant correlation between spatial WM deficit and the region that overlapped the first and second segments of the SLF (SLF I and SLF II). Two patients underwent awake surgery and had difficulties providing the correct responses in the spatial 2-back task with direct subcortical electrical stimulation on the SLF I, which was preserved and confirmed by postoperative diffusion tensor imaging tractography. These patients exhibited no spatial WM deficits during the postoperative immediate and long-term periods. CONCLUSIONS Spatial WM deficits may persist in patients who undergo resection of the tumor located in the right prefrontal brain parenchyma. Injury to the dorsal frontoparietal subcortical white matter pathway, i.e., the SLF I or SLF I and II, could play a causal role in this chronic deficit. A persistent spatial WM deficit, without motor and language deficits, could affect the professional life of the patient. In such cases, awake surgery would be useful to detect the spatial WM network with appropriate task during tumor exploration.

Intraoperative Motor Symptoms during Brain Tumor Resection in the Supplementary Motor Area (SMA) without Positive Mapping during Awake Surgery.

Awake surgery could be a useful modality for lesions locating in close proximity to the eloquent areas including primary motor cortex and pyramidal tract. In case with supplementary motor area (SMA) lesion, we often encounter with intraoperative motor symptoms during awake surgery even in area without positive mapping. Although the usual recovery of the SMA syndrome has been well documented, rare cases with permanent deficits could be encountered in the clinical setting. It has been difficult to evaluate during surgery whether the intraoperative motor symptoms lead to postoperative permanent deficits. The purpose of this study was to demonstrate the intraoperative motor symptoms could be reversible, further to provide useful information for making decision to continue surgical procedure of tumor resection. Eight consecutive patients (from July 2012 to June 2014, six men and two women, aged 33-63 years) with neoplastic lesions around the SMA underwent an awake surgery. Using a retrospective analysis of intraoperative video records, intraoperative motor symptoms during tumor resection were investigated. In continuous functional monitoring during resection of SMA tumor under awake conditions, the following motor symptoms were observed during resection of the region without positive mapping: delayed motor weakness, delay of movement initiation, slowness of movement, difficulty in dual task response, and coordination disturbance. In seven patients hemiparesis observed immediately after surgery recovered to preoperative level within 6 weeks. During awake surgery for SMA tumors, the above-mentioned motor symptoms could occur in area without positive mapping and might be predictors for reversible SMA syndrome.

Predictive value of fractional anisotropy of the arcuate fasciculus for the functional recovery of language after brain tumor resection: a preliminary study.

OBJECTIVE: The arcuate fasciculus has been recognized as an important pathway for language processing. Brain tumors located in proximity to the fasciculus frequently cause preoperative language impairment, and in some cases, no language recovery occurs after tumor resection. No predictive value has been presented for possible postoperative language recovery after tumor resection. The aim of this study is to analyze the preoperative state of the arcuate fasciculus in the patients with brain tumor from the perspective of its usefulness as a predictive factor for postoperative recovery of language functions. METHODS: For 12 right-handed patients with brain tumors in the left hemisphere, preoperative arcuate fasciculi were analyzed with fractional anisotropy (FA) of the diffusion tensor imaging (DTI) tractography. Language functions were evaluated pre- and postoperatively by using the Western Aphasia Battery (WAB). The preoperative value of the FA of the arcuate fasciculus on the lesion side was examined in relation with the language recovery. RESULTS: There was a positive relationship between preoperative increasing values of the FA of the left arcuate fasciculus and improvement of the postoperative total WAB score (p=0.0056), and the scores of the naming (p=0.018), reading (p=0.029), and writing subcategories (p=0.012) CONCLUSION: The preoperative increasing value of the FA of the arcuate fasciculus in the dominant hemisphere could be a predictor for postoperative language recovery following tumor resection. Meticulous procedure should be performed especially in the cases with higher FA of the arcuate fasciculus harboring high possibility of language recovery.

[Awake surgery with line bisection task for two cases of parietal glioma in the non-dominant hemisphere].

Awake surgery for lesions in the non-dominant parietal lobe is rare. We report two cases of right parietal lobe glioma for which awake surgery was performed in order to avoid ataxie optique and hemispatial neglect due to injury in the superior and inferior parietal lobule, respectively. Among several tests to assess the dysfunction of spatial recognition, line bisection test was selected for the task during awake surgery because of its simplicity, easy repetition, and utility. The tumor was successfully removed without any neurological deficit in both the cases. The line bisection test is simple and useful for preserving spatial recognition during an awake surgery.