• Journal of Korean Neurosurgical Society
• /
• v.41 no.6
• /
• pp.371-376
• /
• 2007

Objective : The aim of this study was to investigate the usefulness of diffusion-weighted imaging [DWI] and apparent diffusion coefficiency [ADC] in distinguishing brain abscesses from cystic or necrotic brain tumors, which are difficult to be differentiated by conventional magnetic resonance imaging techniques. Methods : Seven patients with brain abscesses and ten patients with cystic brain tumors were studied from September 2003 to October 2005. Abscess, subdural empyema and ventriculitis were categorized to the abscess group and cystic or necrotic brain gliomas or metastatic brain tumors into the tumor group. Preoperative magnetic resonance images were performed in all patients and diffusion-weighted images and apparent diffusion coefficiency values of lesions were calculated directly from software of 1.5 tesla MRI [General Electrics, USA]. The ratio of the ADC of the lesion to contralateral regional ADC was also measured [relative ADC, rADC]. Results : The average ADC value of pyogenic abscesses group was $0.82+/-0.14{\times}10^{-3}\;[mean+/-S.D.]\;mm^2/s$ and mean rADC was 0.75. Cystic or necrotic areas had high ADC values [$2.49+/-0.79{\times}10^{-3}\;mm^2/s$, mean rADC=2.14]. ADC and rADC values of abscesses group showed about three times lower values than those of cystic or necrotic tumor group. Conclusion : This study results based on numerical comparison of signal intensities and quantitative analysis to distinguish between brain abscess and cystic or necrotic tumor, DWI and ADC mapping are thought to be very useful diagnostic tools.

• Korean Journal of Biological Psychiatry
• /
• v.3 no.1
• /
• pp.66-74
• /
• 1996

There has been an increase in head trauma due to rapid industralization and improvement in transportation. This poses difficulties in differentiating between neuropsychiatric disabilities resulting from real organic changes and those arising from compensation issues. It is the purpose of this study to seek out the differences between normal and abnormal finding group in the structural brain imaging studies via the results of the functional brain imaging studies and psychological tests. Out of 132 subjects, 62 comprised normal and 70 the abnormal finding group. EEG and SPECT were chosen for inspection of functional brain imaging. MMPI and K-WAIS were chosen for psychological test. The subjects were further divided into right hemispheric damage, left hemispheric damage, both hemispheric damage, diffuse damage group and negative group in order to find out whether any differences in the psychological lest results could be localized. The results are as follows : 1) The abnormal finding group, the EEG and SPECT were proven to be a good predictor of brain lesion. This implies that even in the functional brain studies, abnormalities are more easily detected if there are visible brain lesions. 2) The FSIQ of the abnormal finding group is lower than that of normal finding group. this difference is mainly due to low V1Q. The left hemispheric damage group lend to shaw low V1Q. This lowered in was the difference between left hemispheric damage group and negative group. Furthermore, there were no group differences in the PIQ. It is concluded that K-WAIS is effective as evaluator of VIQ mainly of those patients with left hemispheric damage and it is ineffective as a evaluator of PIQ. 3) In the MMPI profile, the both groups displayed high neurotic profiles. There was no difference in the psychotic profiles. The scores of the Depression and Hystery were high in abnormal finding group. This can be seen as one of the lypical findings of chronic head trauma patients. 4) The abnormal finding group tend to be diagnosed as organic mental disorder in the psychological tests more frequently.

• Journal of Veterinary Clinics
• /
• v.35 no.5
• /
• pp.178-183
• /
• 2018

The object of this study was to compare magnetic resonance imaging (MRI) findings and neurological signs in canine brain diseases. Brain diseases can cause severe neurological deficits and may be life-threatening. The antemortem diagnosis of the brain diseases is difficult for the clinician, since definitive diagnosis is based upon histopathological confirmation. Brain diseases are often associated with specific clinical signs, signalment, progression, and location. Accurate lesion localization through neurological examination and MRI findings is helpful for developing a differential diagnosis. A retrospective study was performed to compare the neurological examination of dogs with suspected brain disease to the MRI findings. Based on this study, neurological examination is a reliable way to localize most brain lesions. Postural reaction deficits do not provide sufficient information to localize lesions. Additionally, not all brain lesions present clinical signs and inflammatory lesions may cause no detectable abnormalities on MRI. Therefore, in clinical practice, a combination of neurological examination and MRI findings recommended for accurate brain lesion localization.

• Dementia and Neurocognitive Disorders
• /
• v.16 no.2
• /
• pp.48-53
• /
• 2017

Background and Purpose Torrance Tests of Creative Thinking (TTCT) is a well-known and commonly used measure of creativity. However, the TTCT-induced creative hemodynamic brain activity is rarely revealed. The purpose of this study is to elucidate the neural correlates of creative thinking in the setting of a modified version of the figural TTCT adapted for an functional magnetic resonance imaging (fMRI) experiment. Methods We designed a blocked fMRI experiment. Twenty-five participants (11 males, 14 females, mean age $19.9{\pm}1.8$) were asked to complete the partially presented line drawing of the figural TTCT (creative drawing imagery; creative). As a control condition, subjects were asked to keep tracking the line on the screen (line tracking; control). Results Compared to the control condition, creative condition revealed greater activation in the distributed and bilateral brain regions including the left anterior cingulate, bilateral frontal, parietal, temporal and occipital regions as shown in the previous creativity studies. Conclusions The present revealed the neural basis underlying the figural TTCT using fMRI, providing an evidence of brain areas encompassing the figural TTCT. Considering the significance of a creativity test for dementia patients, the neural correlates of TTCT elucidated by this study may be valuable to evaluate the brain function of patients in the clinical field.

• Investigative Magnetic Resonance Imaging
• /
• v.10 no.1
• /
• pp.26-31
• /
• 2006

Purpose : To evaluate the effect of global scaling analysis on brain activation for sensory and motor functional MR imaging study. Materials and methods : Four normal subjects without abnormal neurological history were included. Arm extension-flexion movement was used for motor function and 1KHz pure tone stimulation was used for auditory function. Functional magnetic resonance imaging was performed at 3T MRI (GE, Milwaukee, USA) using BOLD-EPI technique and SPM2 was employed for data analysis. On data analysis, the brain activation images were obtained with and without global scaling by fixing other parameters such as motion correction and realignment. Results : The difference in brain activation between no scaling and global scaling was not large in case of right upper extremity movement (p<0.000001). For auditory test, brain activation with global scaling showed larger activation than that of without global scaling (p<0.05). Conclusion : A caution must be taken into account when analyzing functional imaging data with global scaling especially for functional study of small local BOLD signal change.

• Korean Journal of Radiology
• /
• v.22 no.1
• /
• pp.118-130
• /
• 2021

Objective: This study aimed to investigate the blood-brain barrier (BBB) disruption in mild traumatic brain injury (mTBI) patients with post-concussion syndrome (PCS) using dynamic contrast-enhanced (DCE) magnetic resonance (MR) imaging and automatic whole brain segmentation. Materials and Methods: Forty-two consecutive mTBI patients with PCS who had undergone post-traumatic MR imaging, including DCE MR imaging, between October 2016 and April 2018, and 29 controls with DCE MR imaging were included in this retrospective study. After performing three-dimensional T1-based brain segmentation with FreeSurfer software (Laboratory for Computational Neuroimaging), the mean K^trans and v_p from DCE MR imaging (derived using the Patlak model and extended Tofts and Kermode model) were analyzed in the bilateral cerebral/cerebellar cortex, bilateral cerebral/cerebellar white matter (WM), and brainstem. K^trans values of the mTBI patients and controls were calculated using both models to identify the model that better reflected the increased permeability owing to mTBI (tendency toward higher K^trans values in mTBI patients than in controls). The Mann-Whitney U test and Spearman rank correlation test were performed to compare the mean K^trans and v_p between the two groups and correlate K^trans and v_p with neuropsychological tests for mTBI patients. Results: Increased permeability owing to mTBI was observed in the Patlak model but not in the extended Tofts and Kermode model. In the Patlak model, the mean K^trans in the bilateral cerebral cortex was significantly higher in mTBI patients than in controls (p = 0.042). The mean v_p values in the bilateral cerebellar WM and brainstem were significantly lower in mTBI patients than in controls (p = 0.009 and p = 0.011, respectively). The mean K^trans of the bilateral cerebral cortex was significantly higher in patients with atypical performance in the auditory continuous performance test (commission errors) than in average or good performers (p = 0.041). Conclusion: BBB disruption, as reflected by the increased K^trans and decreased v_p values from the Patlak model, was observed throughout the bilateral cerebral cortex, bilateral cerebellar WM, and brainstem in mTBI patients with PCS.

• Journal of Korean Neurosurgical Society
• /
• v.46 no.6
• /
• pp.588-591
• /
• 2009

Radiologic findings of Bing-Neel syndrome, which is an extremely uncommon complication resulting from malignant lymphocyte infiltration into the central nervous system (CNS) in patients with Waldenstr$\ddot{o}$m's macroglobulinemia (WM), have been infrequently reported due to extreme rarity of the case. A 75-year-old man with WM presented at a neurology clinic with progressive gait and memory disturbances, and dysarthria of 2 months duration. Cerebrospinal fluid and serum protein electrophoresis and immunofixation electrophoresis showed IgM kappa-type monoclonal gammopathy. Brain magnetic resonance imaging revealed multifocal, hyperintense lesions on T2 weighted-images. Brain diffusion-weighted imaging (DWI) demonstrated hyperintensities in cerebral and cerebellar lesions that appeared isointense on apparent diffusion coefficient maps, which were compatible with vasogenic edema. Although histologic analysis is a confirmative study to prove direct cell infiltration into the brain, brain MRI with DWI may be a good supportive study to diagnose Bing-Neel syndrome.

• Journal of Korean Neurosurgical Society
• /
• v.62 no.6
• /
• pp.723-726
• /
• 2019

We report two rare cases of spontaneously regressed Rathke's cleft cyst (RCC). A 52-year-old woman presented with headache. A pituitary hormone study was normal. Brain magnetic resonance imaging (MRI) showed a $0.45-cm^3$ cystic sellar lesion. The cyst was hyperintense on T1-weighed imaging and hypointense on T2-weighted imaging without rim enhancement, comparable to a RCC. Six months later, brain MRI showed no change in the cyst size. Without any medical treatments, brain MRI 1 year later revealed a spontaneous decrease in cyst volume to $0.05cm^3$. A 34-year-old woman presented with headache and galactorrhea lasting 1 week. At the time of the visit, the patient's headache had disappeared. Her initial serum prolactin level was 81.1 ng/mL, and after 1 week without the cold medicine, the serum prolactin level normalized to 11.28 ng/mL. Brain MRI showed a RCC measuring $0.71cm^3$. Without further treatments, brain computed tomography 6 months later showed a spontaneous decrease in cyst volume to $0.07cm^3$. Another 6 months later, brain MRI revealed that the cyst had remained the same size. Neither patient experienced neurological symptoms, such as headache or visual disturbance, during the period of cyst reduction. The RCCs in both patients underwent spontaneous regression without any medical treatment during a period of 6 months to 1 year. Although spontaneous regression of a RCC is rare, it is still possible and a sufficient follow-up period should be considered.

• Dementia and Neurocognitive Disorders
• /
• v.23 no.3
• /
• pp.127-135
• /
• 2024

Background and Purpose: To ensure data privacy, the development of defacing processes, which anonymize brain images by obscuring facial features, is crucial. However, the impact of these defacing methods on brain imaging analysis poses significant concern. This study aimed to evaluate the reliability of three different defacing methods in automated brain volumetry. Methods: Magnetic resonance imaging with three-dimensional T1 sequences was performed on ten patients diagnosed with subjective cognitive decline. Defacing was executed using mri_deface, BioImage Suite Web-based defacing, and Defacer. Brain volumes were measured employing the QBraVo program and FreeSurfer, assessing intraclass correlation coefficient (ICC) and the mean differences in brain volume measurements between the original and defaced images. Results: The mean age of the patients was 71.10±6.17 years, with 4 (40.0%) being male. The total intracranial volume, total brain volume, and ventricle volume exhibited high ICCs across the three defacing methods and 2 volumetry analyses. All regional brain volumes showed high ICCs with all three defacing methods. Despite variations among some brain regions, no significant mean differences in regional brain volume were observed between the original and defaced images across all regions. Conclusions: The three defacing algorithms evaluated did not significantly affect the results of image analysis for the entire brain or specific cerebral regions. These findings suggest that these algorithms can serve as robust methods for defacing in neuroimaging analysis, thereby supporting data anonymization without compromising the integrity of brain volume measurements.

• Journal of Korean Neurosurgical Society
• /
• v.55 no.3
• /
• pp.131-135
• /
• 2014

Objective : With the growing interests of bacteria as a targeting vector for cancer treatment, diverse genetically engineered Salmonella has been reported to be capable of targeting primary or metastatic tumor regions after intravenous injection into mouse tumor models. The purpose of this study was to investigate the capability of the genetically engineered Salmonella typhimurium (S. typhimurium) to access the glioma xenograft, which was monitored in mouse brain tumor models using optical bioluminescence imaging technique. Methods : U87 malignant glioma cells (U87-MG) stably transfected with firefly luciferase (Fluc) were implanted into BALB/cAnN nude mice by stereotactic injection into the striatum. After tumor formation, attenuated S. typhimurium expressing bacterial luciferase (Lux) was injected into the tail vein. Bioluminescence signals from transfected cells or bacteria were monitored using a cooled charge-coupled device camera to identify the tumor location or to trace the bacterial migration. Immunofluorescence staining was also performed in frozen sections of mouse glioma xenograft. Results : The injected S. typhimurium exclusively localized in the glioma xenograft region of U87-MG-bearing mouse. Immunofluorescence staining also demonstrated the accumulation of S. typhimurium in the brain tumors. Conclusion : The present study demonstrated that S. typhimurium can target glioma xenograft, and may provide a potentially therapeutic probe for glioma.