Differences between primary central nervous system lymphoma and glioblastoma: topographic analysis using voxel-based morphometry.

AIM: To evaluate the diagnostic feasibility of probabilistic analysis using voxel-based morphometry (VBM) in differentiating primary central nervous system lymphoma (PCNSL) from glioblastoma (GBM). MATERIALS AND METHODS: In total, 118 patients with GBM (57 males, 61 females; mean [± standard deviation] age, 56.9±19.3 years; median, 61 years) and 52 patients with PCNSL (37 males, 15 females; mean age, 62±13.3 years, median, 66 years) were studied retrospectively. Each patient underwent preoperative contrast-enhanced T1-weighted imaging (CE-T1WI) using a 1.5 or 3 T magnetic resonance imaging (MRI) system. To assess preferential occurrence sites, images from CE-T1WI were co-registered and spatially normalised using the MNI152 T1 template. Subsequently, a region of interest (ROI) was placed in the centre of the enhancing tumour in normalised images with 1-mm isotropic resolution. The same ROI between normalised and T1 template images was set up using an ROI manager function in ImageJ software. A spherical volume of interest (VOI) with a radius of 10 mm was determined. A probability map was created by overlaying each image with the VOI. Each VOI was removed from T1 template images for VBM analysis. VBM analysis was performed using statistical parametric mapping (SPM) 12 software under default settings. RESULTS: VBM analysis showed significantly higher frequency in the splenium of the corpus callosum among PCNSL patients than among GBM patients (p<0.05; family-wise error correction). CONCLUSION: Topographic analysis using VBM provides useful information for differentiating PCNSL from GBM.

Intravoxel Incoherent Motion MR Imaging of Pediatric Intracranial Tumors: Correlation with Histology and Diagnostic Utility.

BACKGROUND AND PURPOSE: Intravoxel incoherent motion imaging, which simultaneously measures diffusion and perfusion parameters, is promising for brain tumor grading. However, intravoxel incoherent motion imaging has not been tested in children. The purpose of this study was to evaluate the correlation between intravoxel incoherent motion parameters and histology to assess the accuracy of intravoxel incoherent motion imaging for pediatric intracranial tumor grading. MATERIALS AND METHODS: Between April 2013 and September 2015, 17 children (11 boys, 6 girls; 2 months to 15 years of age) with intracranial tumors were included in this retrospective study. Intravoxel incoherent motion parameters were fitted using 13 b-values for a biexponential model. The perfusion-free diffusion coefficient, pseudodiffusion coefficient, and perfusion fraction were measured in high- and low-grade tumors. These intravoxel incoherent motion parameters and the ADC were compared using the unpaired t test. The correlations between the intravoxel incoherent motion parameters and microvessel density or the MIB-1 index were analyzed using the Spearman correlation test. Receiver operating characteristic analysis was used to evaluate diagnostic performance. RESULTS: The perfusion-free diffusion coefficient and ADC were lower in high-grade than in low-grade tumors (perfusion-free diffusion coefficient, 0.85 ± 0.40 versus 1.53 ± 0.21 × 10-3 mm2/s, P < .001; ADC, 1.04 ± 0.33 versus 1.60 ± 0.21 × 10-3 mm2/s, P < .001). The pseudodiffusion coefficient showed no difference between the groups. The perfusion fraction was higher in high-grade than in low-grade tumors (21.7 ± 8.2% versus 7.6 ± 4.3%, P < .001). Receiver operating characteristic analysis found that the combined perfusion-free diffusion coefficient and perfusion fraction had the best diagnostic performance for tumor differentiation (area under the curve = 0.986). CONCLUSIONS: Intravoxel incoherent motion imaging reflects tumor histology and may be a helpful, noninvasive method for pediatric intracranial tumor grading.

Predicting TERT promoter mutation using MR images in patients with wild-type IDH1 glioblastoma.

PURPOSE: The purpose of this study was to identify magnetic resonance imaging (MRI) features that are associated with telomerase reverse transcriptase promoter mutation (TERTm) in glioblastoma. MATERIALS AND METHODS: A total of 112 patients with glioblastoma who had MRI at 1.5- or 3.0-T were retrospectively included. There were 43 patients with glioblastoma with wild-type TERT (TERTw) (22 men, 21 women; mean age, 47±25 [SD] years; age range: 3-84 years) and 69 patients with glioblastoma with TERTm (34 men, 35 women; mean age 64±11 [SD] years; age range, 41--85 years). The feature vectors consist of 11 input units for two clinical parameters (age and gender) and nine MRI characteristics (tumor location, subventricular extension, cortical extension, multiplicity, enhancing volume, necrosis volume, the percentage of necrosis volume, minimum apparent diffusion coefficient [ADC] and normalized ADC). First, the diagnostic performance using univariate and multivariate logistic regression analyses was evaluated. Second, the cross-validation of the support vector machine (SVM) was performed by using leave-one-out method with 43 TERTw and 69 TERTm to evaluate the diagnostic performance. In addition, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for the differentiation between TERTw and TERTm were compared between logistic regression analysis and SVM. RESULTS: With multivariate analysis, the percentage of necrosis volume and age were significantly greater in TERTm glioblastoma than in TERTw glioblastoma. SVM allowed discriminating between TERTw glioblastoma and TERTm glioblastoma with sensitivity, specificity, PPV, NPV, and accuracy of 85.7% [60/70; 95% confidence interval (CI): 75.3-92.9%], 54.8% (23/42; 95% CI: 38.7-70.2%), 75.9% (60/79; 95% CI: 69.1-81.7%), 69.7% (23/33; 95% CI: 54.9-81.3%) and 74.1% (83/112; 95% CI: 65.0-81.9%), respectively. CONCLUSION: The percentage of necrosis volume and age may surrogate for predicting TERT mutation status in glioblastoma.

Breath-hold PET/CT-guided tumour ablation under general anaesthesia: accuracy of tumour image registration and projected ablation zone overlap.

AIM: To assess single-breath-hold combined positron-emission tomography/computed tomography (PET/CT) for accuracy of tumour image registration and projected ablation volume overlap in patients undergoing percutaneous PET/CT-guided tumour-ablation procedures under general anaesthesia. MATERIALS AND METHODS: Eight patients underwent 12 PET/CT-guided tumour-ablation procedures to treat 20 tumours in the lung, liver, or adrenal gland. Using breath-hold PET/CT, the centre of the tumour was marked on each PET and CT acquisition by four readers to assess two- (2D) and three-dimensional (3D) spatial misregistration. Overlap of PET and CT projected ablation volumes were compared using the Dice similarity coefficient (DSC). Interobserver differences were assessed with repeated measure analysis of variance (ANOVA). Technical success and local progression rates were noted. RESULTS: Mean tumour 2D PET/CT misregistrations were 1.02 mm (range 0.01-5.02), 1.89 (0.03-7.85), and 3.05 (0-10) in the x, y, and z planes. Mean 3D misregistration was 4.4 mm (0.36-10.74). Mean projected PET/CT ablation volume DSC was 0.72 (±0.19). No significant interobserver differences in 3D misregistration (p=0.73) or DSC (p=0.54) were observed. Technical success of ablations was 100%; one (5.3%) of 19 tumours progressed. CONCLUSION: Accurate spatial registration of tumours and substantial overlap of projected ablation volumes are achievable when comparing PET and CT acquisitions from single-breath-hold PET/CT. The results suggest that tumours visible only at PET could be accurately targeted and ablated using this technique.

Hookworm-related cutaneous larva migrans in patients living in an endemic community in Brazil: immunological patterns before and after ivermectin treatmen.

Hookworm-related cutaneous larva migrans (Hr-CLM) is caused by animal hookworm larvae migrating in the human epidermis where they elicit an inflammatory response. This study describes the immunological profile in Hr-CLM patients. In 77 Hr-CLM patients from Manaus, Brazil, peripheral eosinophils were counted, and serum concentrations of total immunoglobulin E (IgE) and selected cytokines were determined by ELISA before and after treatment with ivermectin. Controls included patients' household members (endemic controls), non-endemic Brazilian and Japanese individuals. Eosinophil counts and total IgE in Hr-CLM patients were higher than in controls and correlated with disease severity. Concentrations of interleukin (IL)-4, IL-5, IL-6, and IL-10 were higher in Hr-CLM patients than in endemic controls (p < 0.001) while no differences were detected for interferon (IFN)-γ, tumor necrosis factor (TNF)-α, IL-1ß, IL-2, or transforming growth factor (TGF)-ß. Following ivermectin treatment, numbers of eosinophils and concentrations of IL-4, IL-5, and IL-10 decreased whereas IgE, IFN-γ, and TGF-ß concentrations increased. The IL-5/IFN-γ ratio declined from 5.9 (interquartile range [IQR] 0.8-31.6) before to 0.1 (IQR 0.05-0.2; p = 0.001) after treatment. Thus, although an impact of other infections on the immune parameters determined cannot be excluded, Hr-CLM in endemic areas is associated with eosinophilia and elevated cytokine levels, particularly of IL-5 and IL-10, which decrease following ivermectin treatment.

Optimal transseptal puncture location for robot-assisted left atrial catheter ablation.

BACKGROUND: The preferred method of treatment for atrial fibrillation (AF) is by catheter ablation, in which a catheter is guided into the left atrium through a transseptal puncture. However, the transseptal puncture constrains the catheter, thereby limiting its manoeuvrability and increasing the difficulty in reaching various locations in the left atrium. In this paper, we address the problem of choosing the optimal transseptal puncture location for performing cardiac ablation to obtain maximum manoeuvrability of the catheter. METHODS: We have employed an optimization algorithm to maximize the global isotropy index (GII) to evaluate the optimal transseptal puncture location. As part of this algorithm, a novel kinematic model for the catheter has been developed, based on a continuum robot model. Pre-operative MR/CT images of the heart are segmented using the open source image-guided therapy software, 3D Slicer, to obtain models of the left atrium and septal wall. These models are input to the optimization algorithm to evaluate the optimal transseptal puncture location. RESULTS: The continuum robot model accurately describes the kinematics of the catheter. Simulation and experimental results for the optimal transseptal puncture location are presented in this paper. The optimization algorithm generates discrete points on the septal wall for which the dexterity of the catheter in the left atrium is maximum, corresponding to a GII of 0.4362. CONCLUSION: We have developed an optimization algorithm based on the GII to evaluate the optimal position of the transseptal puncture for left atrial cardiac ablation.

Investigation of formaldehyde pollution of tap water and rain water using a novel visual colorimetry.

The pollution of tap water and rain water with formaldehyde in Toyama Pref., Japan was investigated by means of a simple, rapid and cost-effective visual colorimetry developed by us. The levels of formaldehyde in three tap waters from different sources of dams on mountainside and a well-water pumped in urban area in Toyama Pref. were lower than 0.01 mg L(-1) that was the detection limit of the colorimetry. On the other hand, rain waters were seriously polluted with formaldehyde. Rain waters were sampled from three different sites (urban area, top of hill and industrial area) in Toyama Pref. from autumn to winter in 2006. The levels of formaldehyde in the rain waters ranged from 0.07 to 0.30 mg L(-1). The analytical results by the visual colorimetry were in good agreement with those obtained by GC-MS method. It was confirmed that the colorimetry is excellent for practical use for the determination of formaldehyde. It must be concerned about the pollution of rainwater with formaldehyde, when rain water is applied for tap water and miscellaneous purpose.

Mitochondria- and caspase-dependent cell death pathway involved in neuronal degeneration in diabetic retinopathy.

BACKGROUND: Neuronal abnormalities are associated with the pathogenesis of diabetic retinopathy. However, the mechanisms for neuronal cell death in diabetic retinopathy remain unclear. AIM: To determine whether altered expression of Bax, caspase-9 and -3 is associated with degenerative neurons in diabetic retinopathy. METHODS: Immunohistochemistry was performed on cryosections obtained from five pairs of normal and five pairs of age-matched diabetic human retinas. Diabetic eyes had no proliferative diabetic retinopathy and no histories of photocoagulation or ocular surgery. In this study, Fluoro-Jade B (FJB) was used as a marker for identification of degenerative neurons. RESULTS: In diabetic retinas, Bax overexpression coexisted with FJB positive signals in the ganglion cell layer (GCL) compared with very low FJB levels in the normal retina. Increased level of the active forms of caspase-9 and -3 expressions coexisted with FJB positive cells in the GCL of diabetic retinas compared with those in normal retinas. CONCLUSIONS: Upregulation of Bax, caspase-9 and -3 expression was associated with neuronal degeneration in diabetic retinopathy. The mitochondria- and caspase-dependent cell-death pathway may be, in part, associated with neuronal degeneration in diabetic retinas.

Robot-assisted needle placement in open MRI: system architecture, integration and validation.

In prostate cancer treatment, there is a move toward targeted interventions for biopsy and therapy, which has precipitated the need for precise image-guided methods for needle placement. This paper describes an integrated system for planning and performing percutaneous procedures with robotic assistance under MRI guidance. A graphical planning interface allows the physician to specify the set of desired needle trajectories, based on anatomical structures and lesions observed in the patient's registered pre-operative and pre-procedural MR images, immediately prior to the intervention in an open-bore MRI scanner. All image-space coordinates are automatically computed, and are used to position a needle guide by means of an MRI-compatible robotic manipulator, thus avoiding the limitations of the traditional fixed needle template. Automatic alignment of real-time intra-operative images aids visualization of the needle as it is manually inserted through the guide. Results from in-scanner phantom experiments are provided.

Patient specific simulation and navigation of ventriculoscopic interventions.

In this paper a comprehensive framework for pre-operative planning, procedural skill training, and intraoperative navigation is presented. The goal of this system is to integrate surgical simulation with surgical planning in order to improve the individual treatment of patients. Various surgical approaches and new, more complex procedures can be assessed using a safe and objective platform that will allow the physicians to explore and discuss possible risks and benefits prior to the intervention. A simulation environment extends the pre-operative planning in a natural way, as it allows for direct evaluation of the surgical approach envisioned for each case. In addition, by providing intraoperative navigation based on this simulation, surgeons can carry out the previously optimized plan with higher precision and greater confidence.

Needle artifact localization in 3T MR images.

This work explores an image-based approach for localizing needles during MRI-guided interventions, for the purpose of tracking and navigation. Susceptibility artifacts for several needles of varying thickness were imaged, in phantoms, using a 3 tesla MRI system, under a variety of conditions. The relationship between the true needle positions and the locations of artifacts within the images, determined both by manual and automatic segmentation methods, have been quantified and are presented here.

Robot-assisted needle placement in open-MRI: system architecture, integration and validation.

This work describes an integrated system for planning and performing percutaneous procedures-such as prostate biopsy-with robotic assistance under MRI-guidance. The physician interacts with a planning interface in order to specify the set of desired needle trajectories, based on anatomical structures and lesions observed in the patient's MR images. All image-space coordinates are automatically computed, and used to position a needle guide by means of an MRI-compatible robotic manipulator, thus avoiding the limitations of the traditional fixed needle template. Direct control of real-time imaging aids visualization of the needle as it is manually inserted through the guide. Results from in-scanner phantom experiments are provided.

An ultrasound-driven needle-insertion robot for percutaneous cholecystostomy.

A real-time ultrasound-guided needle-insertion medical robot for percutaneous cholecystostomy has been developed. Image-guided interventions have become widely accepted because they are consistent with minimal invasiveness. However, organ or abnormality displacement due to involuntary patient motion may undesirably affect the intervention. The proposed instrument uses intraoperative images and modifies the needle path in real time by using a novel ultrasonic image segmentation technique. In phantom and volunteer experiments, the needle path updating time was 130 and 301 ms per cycle, respectively. In animal experiments, the needle could be placed accurately in the target.

An Er:YAG laser bone cutting manipulator for precise rotational acetabular osteotomy.

Rotational acetabular osteotomy (RAO) has an important advantage in that surgical bony defects are reconstructed with a patients' own tissue. We propose a surgical robot for the RAO using Er:YAG laser irradiating mounted on iliac bone to operate RAO precisely and to reduce recovery and trauma. A water-cooling Er:YAG laser (30 J/cm/sup 2/, l=2.94 mum, 20 Hz, 200 msec) that used optical fiber was operated 4-8 irradiation-overlapping ratio. We kept the distance between the laser and the bone at 0.25 mm using force sensor and spring to maintain effective ablation. Swine scapulae were ablated and performance was evaluated. The manipulator was operated mounting on iliac bone to get a filed position whereby resulting in precise bone cutting. The precision of the manipulator was within 0.3 mm and the efficiency of laser bone ablations per unit time optimized to 0.21 mm/sup 3//secW at the overlapping ratio of the irradiation area was 0.8, meaning a given ablated area was irradiated five times. The troughs showed m charring at this condition and the temperature of the surface was raised to 41.3 degrees C and it lasted only 5 seconds. We are sure that this research will be applied to orthopedics in the near future.

Transportation and fate of cationic surfactant in river water.

The degradation, sorption, transportation and material balance of cationic surfactants discharged from domestic waste into river water was studied. Ion-pair solid-phase extraction behavior showed that the sorption of cationic surfactants as an ion-pair with anionic surfactant onto river sediment was so strong that little cationic surfactant was found in the bulk water. Cationic surfactant was found in river sediment at more than 500 times higher concentration than that in the bulk water. The degradation of the cationic surfactant was very slow in river water and much slower in the sediment. A material balance of cationic surfactant was estimated for a river running through Toyama City by measuring the flow rate and the concentration of cationic surfactant in the water at several points. It was found that more than 30% of cationic surfactant introduced to the river was lost during the river running through ca. 3 km in 3 h. This reduction probably comes from a quick transfer of the cationic surfactant from river water to sediment and water weed by means of adsorption or precipitation with suspending solids.

Relation between brain displacement and local cerebral blood flow in patients with chronic subdural haematoma.

OBJECTIVES: To evaluate the relation between brain displacement, clinical signs and symptoms, and local cerebral blood flow (lCBF) in patients with chronic subdural haematoma (CSDH). METHODS: Forty five patients (age range 58-87 years, mean 71.9 (SD 8.4)) with unilateral CSDH were studied. Patients were categorised into three groups: I, headache (n=16); II, paresis (n=14); and III, mental change (n=15). T1 weighted MR images were obtained in all patients preoperatively. Quantitative values of maximum haematoma thickness, midline shift, and brain rotation angle were measured on axial and coronal MR images. In 21 patients, lCBF was measured by Xe enhanced CT. Values for lCBF were obtained in selected regions of interest in the frontal cortex, thalamus, and hemisphere on both the haematoma and contralateral sides. RESULTS: The lCBF reduction in the ipsilateral frontal cortex showed the best linear correlation with haematoma thickness (r=0.57), whereas the reduction in the ipsilateral thalamus had the most significant correlation with pineal shift (r=0.65) and third ventricle incline (r=0.67). In patients with paresis, lCBF decreased significantly on the ipsilateral side of both the frontal cortex and thalamus (p<0.05), whereas patients with mental change showed a significant reduction of lCBF on both sides of the thalamus (p<0.01) and in the ipsilateral frontal cortex (p<0.01). CONCLUSIONS: The lCBF reduction and clinical symptoms correlated well with local brain displacement in patients with CSDH. The lCBF in the central cerebral area including the thalamus was reduced in patients with clinical signs. The mental changes found were thought to derive from mild impairment of consciousness due to upper brain stem displacement.

Lack of antagonism between nicorandil and sulfonylurea in stable angina pectoris.

The aim of this study was to clarify whether or not nicorandil (a potassium channel opener) caused adverse reactions in patients with angina pectoris who also had diabetes mellitus treated with sulfonylurea (a potassium channel inhibitor). Nineteen diabetic patients with angina pectoris were enrolled, eight were treated with glibenclamide (group A) and 11 were not (group B). Treadmill exercise testing and frequency of anginal attacks were used to evaluate the severity of angina pectoris. Blood sugar and hemoglobin A1c were measured for evaluation of diabetes mellitus control. Exercise tolerance, frequency of anginal attacks and diabetes mellitus control were not perturbed by treatment in either group. In conclusion, there were no antagonistic reactions from the combination of nicorandil with sulfonylurea in angina pectoris complicated by diabetes mellitus.

Reversibility of n-3 fatty acid deficiency-induced alterations of learning behavior in the rat: level of n-6 fatty acids as another critical factor.

Rats fed a semipurified diet supplemented with 3% (w/w) safflower oil [Saf, n-3 fatty acid deficient, high linoleic acid (18:2n-6)] through two generations exhibit decreased correct response ratios in a brightness-discrimination learning test compared with rats fed 3% perilla oil [Per, high alpha-linolenic acid (18:3n-3)]. This is associated with a decreased DHA (22:6n-3)-to-arachidonic acid (20:4n-6) ratio in brain lipids. In the first set of experiments, dietary oil was shifted from Saf to a mixture of 2.4% safflower oil plus 0.6% DHA after weaning (Saf-DHA), but all parameters measured in the learning test were essentially unchanged. Brain 22:6n-3 content of the Saf-DHA group reached that of the Per group but the levels of 20:4n-6 and docosatetraenoic acid (22:4n-6) did not decrease to those of the Per group at the start of the test. In the second set of experiments, dietary oil was shifted to a mixture of 0.6% safflower oil plus 1.2% oleic acid (OA) plus 1.2% DHA (Saf-OA-DHA group) with 18:2n-6 content comparable to that of the Per group. The Saf-OA-DHA group exhibited a learning performance similar to that of the Per group; brain 22:6n-3, 20:4n-6, and 22:4n-6 contents were also comparable to those of the Per group. These results indicate that the altered learning behavior associated with a long-term n-3 fatty acid deficiency is reversed by supplementing 22:6n-3 after weaning, when the levels of competing n-6 fatty acids in the diet and brain lipids are limited.

[A case of gliomatosis cerebri: remarkable improvement after radiation therapy].

A 30-year-old female case of gliomatosis cerebri, which showed remarkable improvement after radiation therapy is reported. The lesion had spread widely in the frontal and parietal lobes of both sides, causing diffuse swelling of the cerebral hemispheres. A specimen obtained by open biopsy revealed diffuse proliferation of astrocytic (GFAP positive) tumor cells, associated with little tissue destruction. After whole-brain radiation of 60 Gy, the lesion shrunk gradually but markedly. Hemiparesis and mild dementia, which the patient had experienced before treatment, subsided completely within 6 months, until she was able to restart her job as a dentist. Although gliomatosis cerebri is thought to have a poor prognosis, this case demonstrates the potential of radiotherapy for this disease. Factors which may lead to a better outcome are discussed.