Biological relevance of tissue factor and IL-6 in arteriovenous malformations.

Arteriovenous malformations (AVMs) are congenital abnormal vessels that shunt blood directly from the arterial to the venous system without a capillary bed. The underlying pathology of AVMs is not fully understood. The objective of the study was to determine the association between the expression patterns of tissue factor (TF) and interleukin-6 (IL-6) in AVMs with clinical and pathological findings. Eighteen cases of sporadic AVM with operative specimens were included in this study. The expression of messenger RNA (mRNA) of TF and IL-6 was assayed, and association with clinical factors was investigated. The distribution of TF and IL-6 was examined with immunofluorescence. The mRNA expression of TF was significantly higher in AVM specimens than in control tissues (P = 0.002) and significantly higher in the symptomatic group than in the asymptomatic group (P = 0.037). The mRNA expression of IL-6 was likewise significantly higher in AVM specimens than in control tissues (P = 0.038). Examination of immunostained sections indicated that TF+ cells were also positive for IL-6 and were distributed around normal endothelial cells and pericytes. Moreover, TF+/IL-6+ cells also expressed CD31, vascular endothelial growth factor receptor 2 (VEGFR2), and platelet-derived growth factor receptor beta (PDGFR-beta). These results suggest that TF is elevated in AVMs and that it mediates symptomatic events. IL-6 is associated with the angiogenic activity of TF, and both are present in the same abnormal endothelial cells and pericytes. These factors may have interactive effects and may serve in a prognostic role for AVMs.

Diagnosis of moyamoya disease on magnetic resonance imaging: are flow voids in the basal ganglia an essential criterion for definitive diagnosis?

Flow voids in the basal ganglia cannot always be recognized on magnetic resonance imaging, even in patients with typical moyamoya disease. In this report, flow voids in the basal ganglia and cisternal flow voids of the sylvian valley were evaluated in patients with moyamoya disease, and their diagnostic value was verified. A total of 41 consecutive patients with moyamoya disease were included in this analysis. The number of flow voids in the basal ganglia and the sylvian valley were counted on each side by 3 observers. Then the numbers of flow voids were compared between the patients with moyamoya disease and controls. The patients with moyamoya disease had a significantly higher mean number of flow voids in the basal ganglia and the sylvian valley (P < .0001); however, the number of flow voids in the basal ganglia was 0 or 1 in 69 sides (28.0%) in patients with moyamoya disease. Comparative analysis using the area under the receiver operating curve indicated that the evaluation of flow voids in the sylvian valley was significantly superior method to that in the basal ganglia (P < .0001). The cutoff value for the number of cisternal flow voids in the sylvian valley for the diagnosis of moyamoya disease was 6. Based on these findings, we recommend a definitive diagnosis of moyamoya disease should include assessment for abnormal vessels around the terminal portions of the internal carotid arteries.

Assessment of moyamoya disease using multidetector row computed tomography.

The recent introduction of multidetector row computed tomography (MDCT) scanners has enabled high-resolution 3-dimensional reconstruction. The purpose of this study was to establish a method to evaluate moyamoya disease using computed tomography angiography (CTA), specifically MDCT. Twenty-four patients (48 sides total) with moyamoya disease diagnosed by magnetic resonance angiography (MRA) were evaluated by means of CTA using MDCT by 3 independent observers, and the resulting 144 sides were analyzed. CTA and MRA were compared in terms of the steno-occlusive changes exhibited in each vessel. CTA and MRA scores were assigned on the basis of the severity of occlusive changes in the internal carotid artery, middle cerebral artery, anterior cerebral artery, and posterior cerebral artery. CTA scores were significantly correlated with MRA scores (P < .0001), and the 2 scores were in complete agreement in 57 sides (39.6%). The mean CTA score was significantly lower than the mean MRA score (P < .0001). Compared with CTA, MRA overestimated occlusion in 115 of the 576 vessels assessed. The mean MRA score was significantly higher in the overestimation group than in the good correlation group (P < .0001). CTA had a significantly higher rate of detection of moyamoya-affected vessels (P = .0001). Our data indicate that CTA using MDCT is a more reliable technique than MRA for diagnosing moyamoya disease. The ability to perform CTA quickly is a significant benefit for patients with moyamoya disease, particularly in pediatric and emergency cases.

[Strategy for the treatment of large-giant aneurysms in the cavernous portion of the internal carotid artery].

The treatment of a large-giant aneurysm in the cavernous portion of an internal carotid artery(ICA)requires occlusion of the ICA, with or without extracranial-intracranial(EC-IC)bypass surgery. Although a balloon occlusion test(BOT)is used to determine the need for bypass surgery and select the bypass type, the criteria are not well established. In this study, we retrospectively analyzed 10 consecutive patients(11 sides)with cavernous large and giant aneurysms treated during the past 8 years. Therapeutic strategies for each patient were selected according to the results of neurological and radiological examinations, and regional cerebral oxygen saturation. A total of 6 high-flow bypasses were placed before ICA occlusions. Three patients had STA-MCA bypasses before ICA occlusions, and two underwent endovascular ICA occlusion without bypass surgery. Favorable outcomes were obtained in all cases with respect to cranial nerve palsy, but one patient had insufficient ipsilateral cerebral blood flow postoperatively, and hemiparesis was revealed. An emergent STA-MCA bypass was performed in this case, which minimized the hemiparesis. Despite radiological evaluation during the BOT procedures, we had one false negative result. This indicates that the BOT requires increased sensitivity and specificity, and that a safety margin should be adopted when determining indications for bypass surgeries.

Endovascular coil embolization of proximal middle cerebral artery aneurysms has better outcomes than other middle cerebral artery aneurysms: A retrospective study.

PURPOSE: Although some authors proposed that coil embolization in middle cerebral artery (MCA) aneurysms is a useful and effective alternative, the characteristics of the aneurysms may be different at each location. We compared the results of coil embolization of proximal middle cerebral artery aneurysms with those of other middle cerebral artery aneurysms. METHODS: Data from 46 patients with 50 aneurysms were retrospectively evaluated. We defined the aneurysms inside of the insular cortex as proximal MCA (pMCA) aneurysms and those outside of the insular cortex as non-proximal MCA (npMCA) aneurysms. The results of the occlusion were divided into classes 1, 2, and 3 of the Raymond scale. We collected the results of the occlusion from the operative notes supplied by a neuroendovascular specialist. RESULTS: Univariate analysis identified favorable results for pMCA aneurysms (class 1: pMCA = 22 npMCA = 11; P < 0.01). In the radiological follow-up results, we achieved class 1 in 29 patients (69%; pMCA = 21 and npMCA = 8; P < 0.01). Side wall type aneurysms (pMCA = 14, npMCA = 2; P < 0.01) and the number of branches from the neck of ≤1 (pMCA = 14, npMCA = 2; P < 0.01) were significantly recognized at the pMCA. CONCLUSIONS: Proximal middle cerebral artery aneurysm clipping is difficult because the origin of the lenticulostriate arteries is often hidden behind the aneurysmal dome. In the present study, endovascular coil embolization for pMCA aneurysms obtained better results than that for npMCA aneurysms because of the morphological characteristics. Endovascular coil embolization seems to be efficacious for pMCA aneurysms as compared with npMCA aneurysms.

Flow-Diverter Stent for an Unruptured Aneurysm at the Junction of the Internal Carotid Artery and Persistent Primitive Trigeminal Artery: Case Report and Literature Review.

BACKGROUND: Persistent primitive trigeminal artery (PPTA), which is a fetal carotid-basilar anastomosis, is the most common embryologic vascular remnant persisting in adults. Aneurysms can arise between the internal carotid artery (ICA) and PPTA. Here we present a case of ICA-PPTA aneurysm treated with a flow-diverter stent. CASE DESCRIPTION: A 52-year-old woman had left abducens nerve palsy. Imaging detected a large left ICA-PPTA aneurysm, which we chose to treat with a flow-diverter stent after embolizing the PPTA with a coil. Although the abducens nerve palsy did not change, there were no signs of cerebral infarction, and no new symptoms appeared postoperatively. Blood flow in the aneurysm had disappeared on digital subtraction angiography after 6 months. CONCLUSIONS: This is the first case report of ICA-PPTA aneurysm successfully treated with a flow-diverter stent. We could stop blood flow from the posterior circulation by embolizing the PPTA with a coil, allowing the use of a flow-diverter stent. This report can be used as a reference for the procedure in future work.

Arterial Spin Labeling Method as a Supplemental Predictor to Distinguish Between High- and Low-Grade Gliomas.

BACKGROUND: Preoperative evaluation of malignancy in gliomas is important for surgical planning, particularly to determine whether a 1,3-bis-2-chloroethyl-1-nitrosourea wafer should be placed into the tumor cavity. In some cases, the intraoperative pathologic diagnosis of World Health Organization grade differs from the final diagnosis. Supplemental methods in addition to the routine contrast tomography or magnetic resonance imaging sequences may provide a more accurate preoperative diagnosis. Because tumor vascularity has been useful in distinguishing between low- and high-grade gliomas, we evaluated the accuracy of the arterial spin labeling (ASL) method, which could measure the cerebral blood flow (CBF) without using contrast medium, to determine the malignancy of gliomas. METHODS: This study included 102 patients with glioma (grade II, n = 40; grade III, n = 18; grade IV, n = 44). All patients underwent ASL to determine the tumor blood flow (TBF) and CBF in the middle cerebral region. The relative tumor vascular index (tVI), which is calculated as TBF divided by CBF in the contralateral middle cerebral region, was used to avoid dispersion of the absolute TBF value. RESULTS: tVI was significantly greater (1.46 ± 0.751) in high-grade gliomas than in low-grade gliomas (1.05 ± 0.343) (P = 0.003). As for each grade, tVI was statistically higher in grade IV than in grade II (P = 0.03) gliomas. CONCLUSIONS: The noninvasive ASL method provides additional information to distinguish high-grade glioma from low-grade gliomas without using contrast medium.

Actin, alpha, cardiac muscle 1 (ACTC1) knockdown inhibits the migration of glioblastoma cells in vitro.

BACKGROUND: Recurrence is inevitable in glioblastomas (GBMs) and requires multifactorial processes. One of the factors that cause recurrence is the strong migratory capacity of GBM cells. We recently reported that actin, alpha, cardiac muscle 1 (ACTC1) could serve as a marker to detect GBM migration in clinical cases. OBJECTIVE: This study aimed to clarify whether the knockdown of highly expressed ACTC1 can inhibit the migratory capacity of cells in the GBM cell line. METHODS: ACTC1 expression was examined using immunocytochemistry and droplet digital polymerase chain reaction. The motility of GBM cells that were either treated with siRNA to knock down ACTC1 or untreated were investigated using a time-lapse study in vitro. RESULTS: The relatively high ACTC1 expression was confirmed in a GBM cell line, i.e., U87MG. The ACTC1 expression in U87MG cells was significantly inhibited by ACTC1-siRNA (p < 0.05). A cell movement tracking assay using time-lapse imaging demonstrated the inhibition of U87MG cell migration by ACTC1 knockdown. The quantitative cell migration analysis demonstrated that the distance traversed during 72 h was 3607 ±â€¯458 (median ±â€¯SD) µm by untreated U87MG cells and 3570 ±â€¯748 µm by negative control siRNA-treated cells. However, the distance migrated by ACTC1-siRNA-treated cells during 72 h was significantly shorter (1265 ±â€¯457 µm, p < 0.01) than the controls. CONCLUSION: ACTC1 knockdown inhibits U87MG cell migration.

Progressive edematous lesions in subacute phase after neuroendovascular therapy.

BACKGROUND: The appearance of edematous lesions in the subacute phase is a rare complication following neuroendovascular therapy. Effective management of these lesions remains unclear. In this report, a case with progressive edematous lesions in the subacute phase after neuroendovascular therapy was described, and the clinical features and therapeutic strategies were discussed. CASE DESCRIPTION: A 54-year-old female with a large, right cavernous internal carotid artery aneurysm was treated with a flow diverter. Left hemiparesis developed 15 days after the procedure, and multiple edematous lesions in areas of prior catheter procedures were revealed on radiological findings. Steroid pulse therapy was employed, and the lesions were gradually reduced without any additional neurological deficits. No recurrence was recognized in the follow-up study. CONCLUSION: In some reports, pathological findings indicate that these lesions result from the presence of foreign bodies, and emboli could be caused by cotton fibers or hydrophilic polymers used as surface coatings on endovascular catheters. In this case, the edematous lesions were most likely caused by hydrophilic polymer emboli. Steroid pulse therapy had a beneficial effect on the lesions. It is important to effectively manage prescribed periods after the procedure to avoid such a rare complication.

Digital Polymerase Chain Reaction Quantification of SERPINA1 Predicts Prognosis in High-Grade Glioma.

BACKGROUND: SERPINA1 plays an anti-inflammatory role in protecting tissues from proteolytic mechanisms. SERPINA1 is positive in gliomas by immunohistochemical analysis; however, the role of SERPINA1, including the relationship with prognosis, has been uncertain. In recent years, digital polymerase chain reaction (PCR) has provided ultra-sensitive assessment of messenger RNA expression from formalin-fixed paraffin-embedded (FFPE) tissues. OBJECTIVE: In this study, we quantitatively determined the expression of SERPINA1 in high-grade gliomas (HGGs) using digital PCR, and we analyzed its relationship with prognosis. METHODS: Twenty-nine FFPE surgical samples from patients with HGGs (7 of World Health Organization [WHO] grade III and 22 of WHO grade IV), and human glioblastoma cell lines, U87 and U118, were used for analysis. A qualitative assessment using immunostaining and quantitative assessment using digital PCR were performed to assess the expression of SERPINA1. RESULTS: The expression of SERPINA1 was demonstrated in glioma tissues and glioblastoma multiforme cell lines by immunostaining. Digital PCR analysis showed that SERPINA1 was expressed in 14.3% and 63.6% of the tissues from patients with grade III and grade IV HGG, respectively (P = 0.035). The median overall survival of 38.8 months in the low SERPINA1 expression group was longer than that of 15.3 months in the high expression group (P = 0.030). CONCLUSIONS: The frequency and the amount of SERPINA1 expression were higher in grade IV than in grade III HGGs. The high expression of SERPINA1 indicates a poor prognosis of HGGs.

Interleukin-13 receptor alpha 2 as a marker of poorer prognosis in high-grade astrocytomas.

BACKGROUND: Interleukin-13 receptor alpha 2 (IL13Rα2) is considered a prognostic marker for gliomas according to the World Health Organization (WHO) grade. However, the expression levels of the marker vary from case to case, even within the same grade. We investigated whether IL13Rα2 could serve as a predictor of poorer prognosis in gliomas. METHODS: mRNA expression of IL13Rα2 was measured using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) in 52 formalin-fixed paraffin-embedded glioma samples (4 pilocytic astrocytomas, 9 diffuse astrocytomas, 12 anaplastic astrocytomas, and 27 glioblastomas, grade IV). The expression levels were compared with regard to WHO grade, MIB-1 index, patient's age, and overall survival. RESULTS: Real time qRT-PCR showed that IL13Rα2 is expressed in a subset of cases with a progressive increase from low- to high-grade astrocytomas (HGAs). The expression had a significant positive correlation with the MIB-1 index and advanced patient age at diagnosis. The overall survival (OS) of patients who had HGAs with higher levels of IL13Rα2 expression was significantly lower than the OS of those with HGAs with lower levels of IL13Rα2. In the 39 HGA cases studied, the median survival benefit in the lower expression group was 167.4 months. The median OS (mOS) in HGA group with lower IL13Rα2 expression was 186.4 months, while the mOS in the group with higher IL13Rα2 expression was 18.6 months (P=0.033). The hazard ratio, adjusted by fitting the Cox proportional hazard models for the mOS in the HGAs with higher IL13Rα2 levels and the HGGs with lower IL13Rα2 levels, was 5.97 (95% CI: 1.76 to 20.32). CONCLUSIONS: The results showed that IL13Rα2 may be used as a marker of poorer prognosis in HGAs, even among tumors of the same grade.

Interhemispheric Asymmetry of Network Connecting Between Frontal and Temporoparietal Cortices: A Corticocortical-Evoked Potential Study.

BACKGROUND: The connection between the ventrolateral frontal and temporoparietal cortices has an important role in language function on the language-dominant side and spatial awareness on the nondominant side. However, the laterality of these pathways remains controversial. We investigated the laterality of this connection using corticocortical-evoked potentials (CCEPs). METHODS: From April 2014 to March 2016, 27 patients who had undergone frontotemporal craniotomy were enrolled. With the patients under general anesthesia, subdural electrodes were placed on both frontal and temporoparietal areas intraoperatively. Alternating 1-Hz electrical stimuli were delivered to the pars opercularis and pars triangularis with a stimulus intensity of 10 mA. CCEPs were obtained from temporoparietal areas by averaging the electrocorticogram time-locked to the stimulus onset. The amplitudes and latencies of the CCEP N1 components were compared between the dominant and nondominant sides. RESULTS: The median amplitudes of the CCEPs were 335.1 µV (range, 60.2-750) and 125.65 µV (range, 55.1-634) on the dominant and nondominant sides, respectively. The CCEP amplitudes were significantly larger on the dominant side than on the nondominant side (P = 0.013). In contrast, the median latency was 27.8 ms (range, 19.3-36.6) on the language-dominant side and 28.9 ms (range, 8.9-38.5) on the nondominant side. The latencies were not significantly different between the 2 sides (P = 0.604). CONCLUSIONS: The CCEP amplitudes were significantly larger in the dominant hemisphere. These findings can lead to better hypotheses regarding the relationship between language functions and the development of the network connecting the frontal and temporoparietal cortices.

Intraoperative Mapping and Monitoring of the Pyramidal Tract Using Endoscopic Depth Electrodes.

OBJECTIVE: To evaluate motor function during neuroendoscopic resectioning of deep-seated brain tumors using endoscopically guided depth electrodes. METHODS: For 12 cases of thalamic tumors, including high-grade gliomas, germinomas, and malignant lymphomas, depth electrodes were inserted using endoscopic guides between the tumor and the pyramidal tract in the thalamus. Motor-evoked potentials (MEPs) were continuously recorded during neuroendoscopic resectioning of the tumors. RESULTS: Monitoring of MEP responses using depth electrodes in all 12 cases was successful. The minimum stimulus intensity threshold required to induce MEP responses was 3 mA. Gross total or subtotal resections were successful with this technique for all patients with glioma. No additional neurologic impairments were found after surgery in any of the cases. CONCLUSIONS: Continuous MEP measurement using depth electrodes can serve as a new monitoring technique for endoscopic resectioning of deep-seated brain tumors.

The influence of depth of anesthesia on motor evoked potential response during awake craniotomy.

OBJECTIVE Motor evoked potentials (MEPs) are a critical indicator for monitoring motor function during neurological surgery. In this study, the influence of depth of anesthesia on MEP response was assessed. METHODS Twenty-eight patients with brain tumors who underwent awake craniotomy were included in this study. From a state of deep anesthesia until the awake state, MEP amplitude and latency were measured using 5-train electrical bipolar stimulations on the same site of the precentral gyrus each minute during the surgery. The depth of anesthesia was evaluated using the bispectral index (BIS). BIS levels were classified into 7 stages: < 40, and from 40 to 100 in groups of 10 each. MEP amplitude and latency of each stage were compared. The deviation of the MEP measurements, which was defined as a fluctuation from the average in every BIS stage, was also considered. RESULTS A total of 865 MEP waves in 28 cases were evaluated in this study. MEP amplitude was increased and latency was decreased in accordance with the increases in BIS level. The average MEP amplitudes in the > 90 BIS level was approximately 10 times higher than those in the < 40 BIS level. Furthermore, the average MEP latencies in the > 90 BIS level were 1.5-3.1 msec shorter than those in the < 60 BIS level. The deviation of measured MEP amplitudes in the > 90 BIS level was significantly stabilized in comparison with that in the < 60 BIS level. CONCLUSIONS MEP amplitude and latency were closely correlated with depth of anesthesia. In addition, the deviation in MEP amplitude was also correlated with depth of anesthesia, which was smaller during awake surgery (high BIS level) than during deep anesthesia. Therefore, MEP measurement would be more reliable in the awake state than under deep anesthesia.

Co-expression of tissue factor and IL-6 in immature endothelial cells of cerebral cavernous malformations.

Cerebral cavernous malformations (CCMs) are congenital abnormal clusters of capillaries that are prone to leaking and thought to result from a disorder of endothelial cells. The underlying pathology of CCM is not fully understood. We analyzed the expression of tissue factor (TF) and interleukin-6 (IL-6) in CCMs to determine the association of TF and IL-6 with clinical and pathological findings. Thirteen cases of operative specimens of sporadic CCMs were included in this study. The expression of messenger RNA of TF and IL-6 was assayed and the association with clinical factors was investigated. Then, the distribution of TF and IL-6 was examined with immunofluorescence. The mRNA expression of TF of CCMs was significantly higher than that of the control (p=0.017), and was correlated with the number of hemorrhage appearances (p=0.190, ρ=0.62). The mRNA expression level of IL-6 was significantly correlated with the mRNA expression level of TF (p=0.034, ρ=0.58). Examination of immunostained sections indicated that TF+ cells were also positive for IL-6, and distributed around normal endothelial cells. Moreover, the TF+/IL-6+ cells expressed CD31 and VEGFR2. The expressions of IL-6 and TF were correlated, and both were present in the same immature endothelial cells. TF is elevated in CCM and might mediate progressive events. These factors may play a prognostic role in CCM.

ACTC1 as an invasion and prognosis marker in glioma.

OBJECTIVE Glioma is a major class of brain tumors, and glioblastoma (GBM) is the most aggressive and malignant type. The nature of tumor invasion makes surgical removal difficult, which results in remote recurrence. The present study focused on glioma invasion and investigated the expression of actin, alpha cardiac muscle 1 (ACTC1), which is 1 of 6 actin families implicated in cell motility. METHODS mRNA expression of ACTC1 expression was analyzed using quantitative real-time polymerase chain reaction (qRT-PCR) in 47 formalin-fixed, paraffin-embedded glioma tissues that were graded according to WHO criteria: Grade I (n = 4); Grade II (n = 12); Grade III (n = 6); and Grade IV (n = 25). Survival was analyzed using the Kaplan-Meier method. The relationships between ACTC1 expression and clinical features such as radiological findings at the time of diagnosis and recurrence, patient age, Karnofsky Performance Scale status (KPS), and the MIB-1 index were evaluated. RESULTS The incidence of ACTC1 expression as a qualitative assessment gradually increased according to WHO grade. The hazard ratio for the median overall survival (mOS) of the patients with ACTC1-positive high-grade gliomas as compared with the ACTC1-negative group was 2.96 (95% CI, 1.03-8.56). The mOS was 6.28 years in the ACTC1-negative group and 1.26 years in the positive group (p = 0.037). In GBM patients, the hazard ratio for mOS in the ACTC1-positive GBMs as compared with the ACTC1-negative group was 2.86 (95% CI 0.97-8.45). mOS was 3.20 years for patients with ACTC1-negative GBMs and 1.08 years for patients with ACTC1-positive GBMs (p = 0.048). By the radiological findings, 42.9% of ACTC1-positive GBM patients demonstrated invasion toward the contralateral cerebral hemisphere at the time of diagnosis, although no invasion was observed in ACTC1-negative GBM patients (p = 0.013). The recurrence rate of GBM was 87.5% in the ACTC1-positive group; in contrast, none of the ACTC1-negative patients demonstrated distant recurrence (0.007). No remarkable relationship was demonstrated among ACTC1 expression and patient age, KPS, and the MIB-1 index. CONCLUSIONS ACTC1 may serve as a novel independent prognostic and invasion marker in GBM.

Intraoperative Subcortical Fiber Mapping with Subcortico-Cortical Evoked Potentials.

OBJECTIVE: During brain surgery, there are difficulties associated with identifying subcortical fibers with no clear landmarks. We evaluated the usefulness of cortical evoked potentials with subcortical stimuli (subcortico-cortical evoked potential [SCEP]) in identifying subcortical fibers intraoperatively. METHODS: We used SCEP to identify the pyramidal tract in 4 patients, arcuate fasciculus in 1 patient, and both in 2 patients during surgical procedures. After resection, a 1 × 4-electrode plate was placed on the floor of the removal cavity and 1-Hz alternating electrical stimuli were delivered to this electrode. A 4 × 5 recording electrode plate was placed on the central cortical areas to map the pyramidal tract and temporoparietal cortical areas for the arcuate fasciculus. SCEPs were obtained by averaging electrocorticograms time locked to the stimulus onset. RESULTS: The subcortical stimulation within 15 mm of the target fiber induced cortical evoked potentials in the corresponding areas, whereas the stimulation apart from 20 mm did not. Five patients showed transient worsening of neurologic symptoms after surgery. However, all patients recovered. CONCLUSIONS: SCEP was useful for identifying subcortical fibers and confirmed the preservation of these fibers. This technique is expected to contribute to the effectiveness and safety of resective surgery in patients with lesions close to eloquent areas.

Intraoperative Mapping and Monitoring for Rootlets of the Lower Cranial Nerves Related to Vocal Cord Movement.

BACKGROUND: Damage to the motor division of the lower cranial nerves that run into the jugular foramen leads to hoarseness, dysphagia, and the risk of aspiration pneumonia; therefore, its functional preservation during surgical procedures is important. Intraoperative mapping and monitoring of the motor rootlets at the cerebellomedullary cistern using endotracheal tube electrodes is a safe and effective procedure to prevent its injury. OBJECTIVE: To study the location of the somatic and autonomic motor fibers of the lower cranial nerves related to vocal cord movement. METHODS: Twenty-four patients with pathologies at the cerebellopontine lesion were studied. General anesthesia was maintained with fentanyl and propofol. A monopolar stimulator was used at amplitudes of 0.05 to 0.1 mA. Both acoustic and visual signals were displayed as vocalis muscle electromyographic activity using endotracheal tube surface electrodes. RESULTS: The average number of rootlets was 7.4 (range, 5-10); 75% of patients had 7 or 8 rootlets. As many as 6 rootlets (2-4 in most cases) were responsive in each patient. In 23 of the 24 patients, the responding rootlets congregated on the caudal side. The maximum electromyographic response was predominantly in the most caudal or second most caudal rootlet in 79%. CONCLUSION: The majority of motor fibers of the lower cranial nerves run through the caudal part of the rootlets at the cerebellomedullary cistern, and the maximal electromyographic response was elicited at the most caudal or second most caudal rootlet. ABBREVIATION: EMG, electromyographic.

IgG4-related disease initially presented as an orbital mass lesion mimicking optic nerve sheath meningioma.

We report a case of an optic nerve mass lesion associated with IgG4-related disease. A 39-year-old man presented with right blurred vision and proptosis 8 years before admission. Magnetic resonance imaging showed a mass lesion in the center of the right orbit, which was diagnosed as optic nerve sheath meningioma by neuroradiologists and neurosurgeons. Irradiation was selected for treatment of the lesion on the basis of the radiological diagnosis; subsequently, the lesion gradually reduced in size. However, regrowth of an optic nerve mass lesion observed during the previous 2 years caused remarkable exophthalmos, and removal of the orbital mass lesion was performed via a transcranial orbital approach. Pathological examinations resulted in a diagnosis of IgG4-related disease, and hematological tests revealed an elevated level of serum IgG4. Additional radiological examinations showed mass lesions in the left maxillary nerve, bilateral inferior alveolar nerves, paravertebral tissue, and left kidney. Treatment with oral steroids has produced a reduction in the size of these lesions.