Search

Objective To describe the personality traits of temperament and character in patients with tinnitus and to identify differences in these traits associated with the severity of tinnitus. Study design Case series with comparisons. Setting Tertiary referral centre. Participants From January to December 2014, one hundred and thirty-four adult patients with chronic subjective tinnitus completed psychoacoustic measurements of tinnitus and the Temperament and Character Inventory (TCI). Measurements Personality traits were assessed by the TCI. The TCI assesses seven dimensions of personality traits and four temperaments ‘novelty seeking, harm avoidance, reward dependence, persistence’, as well as three characters ‘self-directedness, cooperativeness, self-transcendence’. Main outcome measures The values of the TCI parameters in the tinnitus patients were compared with reference data from a non-institutional adult population, and associations between TCI parameter values and tinnitus severity were evaluated. Results In terms of temperament, tinnitus patients had higher scores for ‘harm avoidance’, whereas scores for ‘novelty seeking’, ‘reward dependence’ and ‘persistence’ were significantly lower than the reference. In terms of character, lower ‘cooperativeness’ and ‘self-transcendence’ were identified in the subjects with tinnitus. The ‘novelty seeking’ score was inversely related to tinnitus severity (r = −0.285, P = 0.001), while other temperament and character traits did not show significant correlations. Conclusions There may be a connection between tinnitus and personality traits, especially in the case of ‘novelty seeking’, which is relatively constant over a lifetime. The TCI questionnaire may be useful in facilitating the application of personality traits to tailored counselling for tinnitus.

A membrane material based on polyamide-imide (PAI) has received a great attention lately due to its thermal resistance, outstanding mechanical property, and low thermal expansion coefficient. In this study, we have focused on the preparation of porous PAI nanofiber membranes (PNMs) for water treatments. The preparation of PNMs was completed via the electrospinning method using PAI in a mixed solvent of dimethylacetamide and tetrahydrofuran. The resulting PNMs were then thermally treated to improve mechanical properties. These PAI-based membranes were characterized by scanning electron microscope, tensometer (tensile strength and elongation), pore characteristic, contact angle analyzer (contact angle), and dead-end cell device (water flux). We noticed that the pore diameter (1.0–0.3 μm) of PNMs was systematically controlled by simply increasing the number of PNMs layers. As these nanofiber membranes were found to be highly hydrophobic, we also attempted to prepare hydrophilic PNMs with a PAI solut...

This paper reports the preparation and characterization of polyvinylidene fluoride (PVdF) nanofiber ion exchange membrane for the application in polymer electrolyte membrane fuel cells (PEMFC). The composite membrane of PS/PVdF was prepared by using the electrospinning method with PVdF solution in a mixed solvent of DMAc and acetone by pore-filling with a mixture of styrene and PS using DVB as cross-linking reagent. Ion exchange membrane (SPS/PVdF) was then manufactured by introducing sulfonate (–SO3H) groups using sul-furic acid on the prepared PS/PVdF membranes. The modified membranes were characterized by fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), water uptake, ion exchange capacity (IEC), electrical conductivity and membrane & electrode assembly (MEA). By controlling the content of PS, characteristics comparable to Nafion which has water uptake, IEC and electrical conductivity values suited for the application in PEMFC could be ob...

Purpose It is difficult to differentiate CNS lymphoma from other tumors such as malignant gliomas, metastases, or meningiomas with conventional MR imaging, because the imaging findings are overlapped between these tumors. The purpose of this study is to investigate the perfusion weighted MR imaging findings of CNS lymphomas and to compare the relative cerebral blood volume ratios between CNS lymphomas and other tumors such as high grade gliomas, metastases, or meningiomas. Materials and methods We retrospectively reviewed MRI findings and clinical records in 13 patients with pathologically proven CNS lymphoma between January 2006 and November 2008. We evaluated the relative cerebral blood volume ratios of tumor, which were obtained by dividing the values obtained from the normal white matter on MRI. Results Total 13 patients (M:F = 8:5; age range 46–67 years, mean age 52.3 years) were included. The CNS lymphomas showed relatively low values of maximum relative CBV ratio in most patients regardless of primary or secondary CNS lymphoma. Conclusion Perfusion weighted image may be helpful in the diagnosis of CNS lymphoma in spite of primary or secondary or B cell or T cell.

Purpose To evaluate the value of the high signal intensity halo sign as a new marker of a fresh or recent intraplaque hemorrhage on the maximum intensity projection (MIP) images of time-of-flight (TOF) MR angiography. Materials and Methods A total of 135 consecutive patients were included in this study. High-resolution MRI using 3-inch surface coils was performed on a 1.5T scanner before the carotid endarterectomy. TOF MR angiograms and T2-weighted, T1-weighted pre- and postcontrast fast spin echo images were obtained. The surgical and pathological findings of the carotid artery were analyzed and correlated with the MRI findings. Results A total of 42 atheromas (31.1%) had a fresh or recent intraplaque hemorrhage on the surgicopathological findings. A total of 38 (90.5%) of these patients showed high signal intensity halo around the carotid artery on the MIP images of TOF MR angiography. The high signal intensity halo sign, compared with the surgical and histopathological findings, demonstrated a sensitivity, specificity, positive predictive value, and negative predictive value of 91%, 83%, 72%, and 95%, respectively, with a 95% confidence interval (CI) in the detection of an intraplaque hemorrhage. The multisequence approach suggested the presence of an intraplaque hemorrhage with a sensitivity, specificity, positive predictive value, and negative predictive value of 93%, 85%, 74%, and 96%, respectively, with a 95% CI. Conclusion High signal intensity halo around the carotid artery on the MIP images of TOF MR angiography is useful in the noninvasive detection of a fresh or recent carotid intraplaque hemorrhage. J. Magn. Reson. Imaging 2008;27:1341–1346. © 2008 Wiley-Liss, Inc.

PVDF (Kynar® 761) nanofibers were made by electrospinning with an external voltage of 6–10 kV, a traveling distance of 7–15 cm and a flow rate of 0.4–1 mL/h. Although the mean diameter of the fibers has not changed significantly, the conditions affected the change in diameter distribution. This was attributed to interactions, both attraction and repulsion, between the positive charges on the polymer solutions and the electrically grounded collector. Higher voltages and traveling distance increased the level of attraction between the positive charge on the polymer solution and the electrically grounded collector, resulting in a narrow diameter distribution. In addition, a high flow rate allowed a high population of uniformly charged solutions to travel to the grounded collector, which resulted in a narrow diameter distribution. The optimum conditions for electrospinning of PVDF in DMAc/acetone (3/7 by wt) were a collector voltage of 6 kV, a syringe tip to collector of 7 cm, a flux rate of 0.4 mL/h and 10 kV, 10 cm, 1 mL/h. Since PVDF is widely used as a filtration membrane, it was electrospun on a PET support with a rotating drum as a grounded collector. Surprisingly, some straight nanofibers were separated from the randomly deposited nanofibers. The straight nanofiber area was transparent, while the randomly deposited nanofiber area was opaque. Both straight nanofibers and aligned nanofibers could be obtained by manipulating the PET drum collector. These phenomena were not observed when the support was changed to an Al sheet. This suggests that a pseudo dual collector was generated on the PET sheet. No negative charge was created because the PET sheet was not a conductive material. However, less charge was created when the sheet was not perfectly attached to the metal drum. Hence, the nanofibers jumped from one grounded site to the nearest one, yielding a straight nanofiber.

A patient with chronic cerebral paragonimiasis began to have new motor seizures of the right face manifested by clonic contractions that occurred several hundred times a day, consistent with simple partial status epilepticus. Ictal electroencephalogram discharges started from the left frontal region and then spread to the left hemisphere with left frontal maximum. But clinical seizures were limited to the right face. The frequent partial seizures were controlled by the intravenous infusion of phenytoin. Brain magnetic resonance imaging showed multiple conglomerated round nodules with encephalomalacia in the left temporal and occipital lobes. Applying the technique of ictal-interictal single-photo emission computed tomography subtraction, the authors were able to localize the focal ictal-hyperperfusion on left precentral cortex adjacent to the lesions that correspond to the anatomical distribution of left face motor area.

Objective: The differentiation between orbital lymphoma and subacute or chronic inflammatory pseudotumor (SCIPT) may be difficult clinically and radiologically. The aim of this study was to evaluate the enhancement characteristics of orbital lymphoma and SCIPT with two-phase helical computed tomography (CT) and delayed coronal CT and to determine whether attenuation measurements on CT can be used to differentiate between the 2 diseases. Methods: Nineteen histopathologically proven orbital lymphomas and 9 SCIPTs were examined with two-phase helical CT. After injecting 90 mL contrast material at a rate of 3 mL/s, early- and late-phase axial CT scans were obtained with scanning delays of 30 and 90 seconds, respectively. Delayed coronal scans were obtained with delays of 4-9 minutes. Attenuation of the lesions at each phase was measured quantitatively. Relative percentages of contrast enhancement (CE) were calculated to determine the cutoff value for differentiating SCIPT from lymphoma. Results: The CT attenuation change over time was significantly different between orbital lymphoma and SCIPT (P < 0.05). Increased CT attenuation between early- and late-phase axial scans was seen in 42% (n = 8) of lymphoma cases, and decreased CT attenuation was seen in 58% (n = 11). In 17 lymphomas (90%), the CT attenuation decreased between late-phase axial and delayed coronal scans. Conversely, in 7 SCIPTs (78%), the CT attenuation increased gradually over time from early-phase axial to delayed coronal scans. The relative percentage of CE at the delayed coronal scan had a cutoff value of -6.97%, a sensitivity of 84%, and a specificity of 100%. Conclusion: Different characteristics of attenuation change on two-phase helical CT and delayed coronal CT can be helpful in differentiating between orbital lymphoma and SCIPT.

The purpose of this study was to compare multiphasic perfusion computed tomography (CT) with diffusion and perfusion magnetic resonance imaging (MRI) in predicting final infarct volume, infarct growth, and clinical severity in patients with hyperacute ischemia untreated by thrombolytic therapy.Multiphasic perfusion CT was performed in 19 patients with ischemic stroke within 6 hours of symptom onset. Two CT maps of peak and total perfusion were generated from CT data. Diffusion-weighted imaging (DWI) and perfusion MRI were obtained within 150 minutes after CT. Lesion volumes on CT and MRI were compared with final infarct volume and clinical scores, and mismatch on CT or MRI was compared with infarct growth.The lesion volume on the CT total perfusion map strongly correlated with MRI relative cerebral blood volume (rCBV), and that on the CT peak perfusion map strongly correlated with MRI relative cerebral blood flow (rCBF) and rCBV (P0.001). The lesion volume on unenhanced CT or DWI moderately correlated with final infarct volume, but only lesion volume on unenhanced CT weakly correlated with baseline clinical scores (P = 0.024). The lesion volumes on the CT peak perfusion map and MRI rCBF similarly correlated with final infarct volume and clinical scores and more strongly than those on mean transit time (MTT) or time to peak (TTP). DWI-rCBF or CT mismatch was more predictive of infarct growth than DWI-MTT or DWI-TTP mismatch.Multiphasic perfusion CT is useful and of comparable utility to diffusion and perfusion MRI for predicting final infarct volume, infarct growth, and clinical severity in acute ischemic stroke.

Objective Despite the risk of intracranial hemorrhage, combination therapy with intravenous recombinant tissue plasminogen activator and intraarterial mechanical thrombolysis can be effective for treatment of acute ischemic stroke. We investigated the feasibility and safety of intraarterial tirofiban following formation of anterograde flow after mechanical thrombolysis in acute ischemic stroke. Methods We analyzed data from consecutive patients with acute ischemic stroke, who underwent treatment with intraarterial thrombolysis. All patients were evaluated immediately and 7 days later by computed tomography scanning and magnetic resonance imaging scanning with magnetic resonance angiography. For clinical outcome analysis, we followed up the NIHSS score and modified Rankin Scale score during a period of 3 months. Results Sixteen patients underwent treatment. The mean baseline NIHSS score was 16.1 ± 4.4 points. 75.1% of patients showed angiographic improvement; 43.8% and 31.3% had complete and partial recanalization, respectively. 53.3% and 56.3% showed clinical improvement and favorable outcome at 24 h and 3 months, respectively. One patient had symptomatic intracranial hemorrhage. Conclusions Our results suggest that administration of local intraarterial tirofiban after anterograde flow formation is a viable treatment strategy for patients of acute ischemic stroke for reducing the risk of reocclusion after intraarterial thrombolysis.

Objective HydroCoil (MicroVention, Aliso Viejo, CA), a hydrogel-platinum coil hybrid device, is one of various efforts to overcome delayed recanalization of coiled intracranial aneurysms. The purpose of this study was to investigate the outcome of intracranial aneurysms treated with HydroCoils. Methods This multicenter prospective study included 80 aneurysms in 76 patients treated with HydroCoils. There were 32 (40%) ruptured and 48 (60%) unruptured aneurysms; 22 (28%) were large aneurysms (maximal diameter, > or = 10 mm) and 58 (72%) were small. Aneurysm volumes were 100 mm3 or more in 48 (60%) and less than 100 mm3 in 32 (40%); in 13 aneurysms (16%), volumes were 600 mm3 or more. Efficacy and safety were evaluated on the basis of degree of initial occlusion, procedure-related complications, and the follow-up result. Results Initial aneurysmal occlusion was complete in 60 (75%) aneurysms and near-complete in 14 (17.5%). Procedure-related complications included aseptic meningitis-related problems, including delayed hydrocephalus in 13 patients (28% among cases of unruptured aneurysms) and thromboembolism in two patients. Radiological follow-up data obtained 6 months or more after coil embolization were available in 54 aneurysms (68%) and revealed stable occlusion in 48 (89%) aneurysms, minor recanalization in one (2%), and major recanalization in five (9%). All of the recanalized aneurysms were 600 mm3 or more in volume, and aneurysm volume was a single important variable related to delayed recanalization on multiple logistic regression analysis (P = 0.016). Conclusion HydroCoil embolization seems to be a feasible treatment option in intracranial aneurysms in terms of initial aneurysmal occlusion rate and durability at the time of the follow-up evaluation; however, caution is required regarding aseptic meningitis and delayed hydrocephalus. Calculated aneurysmal volume of 600 mm3 seems to be critical in determining the anatomic outcome in aneurysms embolized with HydroCoils.

This study examined the relationship between the severity of aphasia and regional cerebral perfusion on brain SPECT using statistical parametric mapping (SPM) and a statistical probabilistic anatomic map (SPAM) in patients with a striatocapsular infarction (SCI) along with the other clinical and imaging findings.The subjects were 16 right-handed Korean-speaking patients with a left SCI who underwent 99mTc-ethylcyteinate dimer (99mTc-ECD) SPECT (8.1 +/- 4.8 d [mean +/- SD] after onset). MRI showed that no patient had any abnormality in the cerebral cortex (6.8 +/- 6.0 d after onset). The aphasia quotient (AQ), which is a measure of the severity of aphasia, was obtained by using the Korean version of the Western Aphasia Battery (5.3 +/- 3.9 d after onset). For quantitative evaluation of cerebral perfusion, the asymmetry indices (AIs) for subcortical and cortical areas were calculated using SPM and SPAM. The infarct size was measured using MRI.Aphasia occurred in 15 (2 global, 7 transcortical, and 6 anomic aphasia) of the 16 patients. Left cerebral cortical hypoperfusion was observed in all 15 patients with subcortical aphasia. Aphasia was more severe in 6 patients with extensive cerebral cortical hypoperfusion than in the remaining 10 patients (AQ = 41.8 +/- 25.2 points vs. 84.2 +/- 7.7 points [mean +/- SD], P = 0.001). There was an association between the AQ and age (rho = -0.665), infarct size (rho = -0.594), AIs of the frontal cortex (rho = -0.653), temporal cortex (rho = -0.782), parietal cortex (rho = -0.694), whole cerebral cortex (rho = -0.768), and the cerebellar cortex (rho = 0.765). Voxel-based SPM analysis showed a significant positive correlation between the AQ and the perfusion of the left temporal cortex and the right cerebellum.The severity of subcortical aphasia after a left SCI without cortical abnormalities on MRI is associated with the extent and severity of the left cerebral cortical hypoperfusion on brain perfusion SPECT performed during the subacute stage, particularly in the left temporal cortex. Quantitative brain perfusion SPECT using SPM and SPAM can help in evaluating subcortical aphasia in a SCI because it provides functional information that cannot be obtained by morphologic imaging.

In order to study the flow dynamic changes inside an aneurysm sac due to the partial occlusion of the aneurysm neck, velocity fields were measured using a particle image velocitimeter (PIV) in in vitro aneurysm models under the physiological flow waveform. Lateral aneurysm models arising from the curved parent vessel with different occlusion ratios and sites-e.g. no clip, 50% proximal and distal clip, and 75% proximal and distal clip-were tested. Reduced inflow and intraaneurysmal velocities may provide a better hemodynamic environment for aneurysm embolization. Comparing inflow rates and averaged intraaneurysmal velocities in the proximal and the distal clip model, they were lower in the distal clip model in cases of 50% neck occlusion, but they were lower in the proximal clip model in cases of 75% occlusion. These results suggest that clipping sites for reduced inflow and intraaneurysmal flow velocities may differ for different residual neck sizes. Less effective inflow blocking in the 75% distally clipped model may be due to the curvature of the parent artery. Therefore, not only the residual neck size and clipping site but the geometry of parent vessel significantly affect the flow fields inside the aneurysm, and subsequently the success of the aneurysm treatment.

Objective We investigated low dose digital tomosynthesis (DT) for the evaluation of the paranasal sinus (PNS), and compared its diagnostic accuracy with a PNS radiography series (XR). Materials and Methods We enrolled 43 patients for whom XR, PNS DT, and OMU CT were performed. We measured effective doses (EDs) of XR, DT, and OMU CT using Monte Carlo simulation software. Two radiologists performed independent observation of both XR and DT. For seven PNSs, they scored anatomic conspicuity of sinuses and confidence on the presence of sinusitis using nine point scales. OMU CT was observed by the third radiologist and the findings were regarded as reference standard. We compared scores for conspicuity and sinusitis confidence between XR and DT. Results Mean EDs were 29 ± 6 µSv, 48 ± 10 µSv, and 980 ± 250 µSv, respectively, for XR, DT, and CT. Mean scores for conspicuity were 6.3 and 7.4, respectively, for XR and DT. Sensitivity per patient basis for sinusitis detection were 52% and 96%, respectively, for XR and DT in observer 1 (p = 0.001) and 80% and 92% for observer 2 (p = 0.25). Specificities for sinusitis exclusion were 100% for both XR and DT for observer 1 and 89% and 100% for observer 2 (p = 0.50). Accuracies for sinusitis diagnosis were 72% and 98%, respectively, for XR and DT for observer 1 (p = 0.001) and 84% and 95% for observer 2 (p = 0.125). Conclusion Patient radiation dose from low dose DT is comparable with that of PNS XR. Diagnostic sensitivity of DT for sinusitis was superior to PNS XR.

Objective: We aimed to evaluate the results of endovascular coil embolization for very small aneurysms ( 3 mm). Materials and Methods: Between March 2005 and December 2008, a total of 31 very small aneurysms in 30 patients were treated by coil embolization. Of the 31 aneurysms, five (16%) were ruptured, as opposed to 26 (84%) that were not. We assessed the procedural complications, immediate angiographic outcome after coiling, clinical outcome, and follow-up MR angiography (MRA). Results: Two thromboembolic complications occurred during the procedure, but did not lead to any persistent neurologic deficit. No procedural aneurysmal rupture was observed and procedure-related morbidity and mortality were both 0%. Occlusion was adequate in 25 aneurysms (81%) and incomplete in six aneurysms (19%). The clinical outcomes of five patients with ruptured aneurysms were good (Glasgow outcome scale 4), with no bleeding of the treated aneurysms during a mean follow-up period of 13.3 months. On 27 follow-up MRA, there was no recurrence, and the five incompletely occluded aneurysms showed a spontaneous amelioration resulting in an adequate occlusion. Conclusion: Coil embolization of very small aneurysms is technically feasible with good results. The long-term efficacy and the potential as a standard treatment strategy remain to be determined by randomized large trials.

To evaluate the use of multiphasic helical computed tomography (CT) in predicting subsequent development of severe brain edema in patients with acute middle cerebral artery (MCA) stroke.Case-control study.Tertiary referral hospital.We studied 31 patients with acute MCA stroke who had a baseline National Institutes of Health Stroke Scale score of 15 or higher within 6 hours of symptom onset. Sequential 4-phasic enhanced helical CT scans were performed after taking precontrast CT scans. The severity of perfusion deficit was graded as "severe" or "moderate" depending on collateral blood flow.Patients were classified as having severe brain edema if they showed signs of uncal herniation or deterioration with mass effect leading to hemicraniectomy.Severe brain edema developed in 10 patients (32%). Severe perfusion deficit greater than 50% of the presumed MCA territory on multiphasic helical CT was more often found in patients with severe brain edema than in those without (8 of 10 vs 4 of 21, P =.002). In contrast, parenchymal hypodensity greater than 50% on precontrast CT was observed only in 5 patients with severe brain edema (5 of 10 vs 4 of 21, P =.10). Additional involvement of the anterior or posterior cerebral artery territory was found on multiphasic CT (6 of 10 vs 0 of 21, P.001) and on precontrast CT (4 of 10 vs 0 of 21, P =.007) only in patients with severe brain edema.Multiphasic helical CT is more useful than precontrast CT for predicting subsequent severe brain edema in acute MCA stroke based on the findings of severe perfusion deficit greater than 50% of the MCA territory and additional involvement of the anterior or posterior cerebral artery territory.

Objectives To evaluate the frequency of intracranial atherosclerosis among patients with steno-occlusive extracranial carotid artery disease and to determine if there are factors related to the combined intracranial atherosclerosis. Design Cross-sectional study. Setting A tertiary referral hospital. Patients We studied 142 consecutive patients who had atherosclerotic steno-occlusive lesions (defined as ≥30% narrowing of the luminal diameter or occlusion) of an extracranial carotid artery confirmed by conventional angiography. We excluded patients who had potential cardiogenic sources of embolism. Potential vascular risk factors for each patient were obtained from medical records. Main Outcome Measure We determined the location and severity of atherosclerotic lesions by conventional angiography. We compared the vascular risk factors between patients with steno-occlusive extracranial carotid artery disease alone and patients with combined intracranial atherosclerosis and extracranial carotid artery disease. Results Intracranial steno-occlusive lesions (≥30% stenosis or occlusion) were found in 80 patients (56.3%). Of 121 patients with significant (≥50% stenosis or occlusion) extracranial carotid artery disease, 58 (47.9%) also had significant lesions of intracranial arteries. Univariate and multivariate analyses showed that diabetes mellitus was the only significant factor associated with combined intracranial atherosclerosis in patients with extracranial carotid artery disease. Conclusions Intracranial atherosclerosis is common in Korean patients with steno-occlusive extracranial carotid artery disease. Diabetes mellitus is associated with intracranial atherosclerosis in patients who had steno-occlusive extracranial carotid artery disease.