PURPOSE: The objective of this study was to investigate effects of different smoothing kernel sizes on brain tissue-masked susceptibility-weighted images (SWI) obtained from normal elderly subjects using voxel-based analyses. MATERIALS AND METHODS: Twenty healthy human volunteers (mean age+/-SD = 67.8 +/- 6.09 years, 14 females and 6 males) were studied after informed consent. A fully first-order flow-compensated three-dimensional (3D) gradient-echo sequence ran to obtain axial magnitude and phase images to generate SWI data. In addition, sagittal 3D T1-weighted images were acquired with the magnetization-prepared rapid acquisition of gradient-echo sequence for brain tissue segmentation and imaging registration. Both paramagnetically (PSWI) and diamagnetically (NSWI) phase-masked SWI data were obtained with masking out non-brain tissues. Finally, both tissue-masked PSWI and NSWI data were smoothed using different smoothing kernel sizes that were isotropic 0, 2, 4, and 8 mm Gaussian kernels. The voxel-based comparisons were performed using a paired t-test between PSWI and NSWI for each smoothing kernel size. RESULTS: The significance of comparisons increased with increasing smoothing kernel sizes. Signals from NSWI were greater than those from PSWI. The smoothing kernel size of four was optimal to use voxel-based comparisons. The bilaterally different areas were found on multiple brain regions. CONCLUSION: The paramagnetic (positive) phase mask led to reduce signals from high susceptibility areas. To minimize partial volume effects and contributions of large vessels, the voxel-based analysis on SWI with masked non-brain components should be utilized.
Aged ; Brain* ; Female ; Healthy Volunteers ; Humans ; Informed Consent ; Masks

OBJECTIVE: The purpose of this study was to compare the histogram analysis and visual scores in 3T MRI assessment of middle cerebral arterial wall enhancement in patients with acute stroke, for the differentiation of parent artery disease (PAD) from small artery disease (SAD). MATERIALS AND METHODS: Among the 82 consecutive patients in a tertiary hospital for one year, 25 patients with acute infarcts in middle cerebral artery (MCA) territory were included in this study including 15 patients with PAD and 10 patients with SAD. Three-dimensional contrast-enhanced T1-weighted turbo spin echo MR images with black-blood preparation at 3T were analyzed both qualitatively and quantitatively. The degree of MCA stenosis, and visual and histogram assessments on MCA wall enhancement were evaluated. A statistical analysis was performed to compare diagnostic accuracy between qualitative and quantitative metrics. RESULTS: The degree of stenosis, visual enhancement score, geometric mean (GM), and the 90th percentile (90P) value from the histogram analysis were significantly higher in PAD than in SAD (p = 0.006 for stenosis, < 0.001 for others). The receiver operating characteristic curve area of GM and 90P were 1 (95% confidence interval [CI], 0.86–1.00). CONCLUSION: A histogram analysis of a relevant arterial wall enhancement allows differentiation between PAD and SAD in patients with acute stroke within the MCA territory.
Arteries* ; Constriction, Pathologic ; Humans ; Magnetic Resonance Imaging ; Middle Cerebral Artery ; Parents* ; ROC Curve ; Stroke ; Tertiary Care Centers

OBJECTIVE: To compare apparent diffusion coefficients (ADCs) of brain segments by using two diffusion-weighted imaging acquisition modes, single-shot echo-planar imaging (ss-EPI) and read-out-segmented echo-planar imaging (rs-EPI), and to assess their correlation and agreement in healthy controls. MATERIALS AND METHODS: T2-weighted (T2W) images, rs-EPI, and ss-EPI of 30 healthy subjects were acquired using a 3T magnetic resonance scanner. The T2W images were co-registered to the rs-EPI and ss-EPI, which were then segmented into the gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) to generate masking templates. ADC maps of rs-EPI and ss-EPI were also segmented into the GM, WM, and CSF by using the generated templates. ADCs of rs-EPI and ss-EPI were compared using Student's t tests and correlated using Pearson's correlation coefficients. Bland-Altman plots were used to assess the agreement between acquisitions.
Brain ; Cerebrospinal Fluid ; Diffusion ; Echo-Planar Imaging ; Gray Matter ; Healthy Volunteers ; Magnetic Resonance Imaging ; Masks ; White Matter

BACKGROUND: Two genetic loci, PKD1 and PKD2, have been identified as being responsible for ADPKD, and PKD1 is known to be associated with poor prognosis. However, the presence of intrafamilial clinical diversity suggests the presence of disease-modifying loci. Because the mechanism of renal failure in ADPKD includes cystic growth and tubulointerstitial atrophy and fibrosis, we studied the associations between two cytokine gene polymorphisms in the TGF-beta gene, which are known to be related with chronic tubulointerstitial inflammation, and ADPKD progression in Korean patients. METHODS: 47 normal controls and 114 individuals with ADPKD were genotyped by PCR-RFLP, and the TGF-beta gene leader sequence of T869C(Leu10Pro) variant was compared with MspA1I and G915C (Arg25Pro) with BglI. Statistic significances were determined using the Chi-square test. RESULTS: The distribution of alleles for the TGF-beta Leu10Pro polymorphism in ADPKD was : T 52%, C 48%, which was similar to the Korean(56 : 44, p= 0.670) and Western controls(65 : 35), and in addition, no differences were found between the CRF and the non-CRF groups(p=0.571) or the early hypertension and the normotension groups(p=0.252). The distribution of alleles for the TGF-beta Arg25Pro polymorphism was all GG type, which was different from Western controls(90 : 10, p=0.000). CONCLUSION: Our results suggest that the polymorphism at Arg25Pro of TGF-beta in Korean population has different allele distribution from Western, and the polymorphism at Leu10Pro of TGF-beta has no association with the renal progression of Korean ADPKD patients.
Alleles ; Atrophy ; Fibrosis ; Genetic Loci ; Humans ; Hypertension ; Inflammation ; Polycystic Kidney, Autosomal Dominant* ; Prognosis ; Renal Insufficiency ; Transforming Growth Factor beta*

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary renal disease in adults, and its major morbidities are renal failure and cerebrovascular accident. The prevalence of this disease in the chronic haemodialysis patient population is known to be approximately 2% in Korea. So far, three genetic loci have been identified as being responsible for ADPKD, and approximately 85% of the cases in Western countries are related to the PKD1 gene. However, little information is available concerning the pattern of linkage analysis or the mutations present in Asian populations. For this study, 35 families with hereditary renal cysts were recruited from our ADPKD clinic from 1993 to the present, and their molecular genetic characteristics were studied. Subjects were chosen according to the criteria of Ravine et al. Linkage analysis was done with microsatellite markers(PKD1:SM7, UT581, AC2.5, KG8, D16S418, PKD2 : D4S423, D4S1534, D4S1542, D4S1544, D4S2460). Genomic DNA PCR and PAGE gel run were done, and the allele patterns were compared with sonographic findings. The results of this study showed that the ratio of PKD1 to PKD2 was 23 : 3, and PKD2 families showed the tendency of milder renal prognosis than PKD1 families. In conclusion, we confirmed the usefulness of linkage analysis for ADPKD in Korean population, and our data shows a similar percentage of PKD1(88%) and PKD2(12%) in Korean patients as in the Western population.
Adult ; Alleles ; Asian Continental Ancestry Group ; DNA ; Genetic Loci ; Genotype* ; Humans ; Korea ; Microsatellite Repeats ; Molecular Biology ; Polycystic Kidney, Autosomal Dominant* ; Polymerase Chain Reaction ; Prevalence ; Prognosis ; Renal Insufficiency ; Stroke ; Ultrasonography

End stage renal disease(ESRD) is a well-known major complication of autosomal polycystic kidney disease(ADPKD). Several risk factors of renal progression in ADPKD were identified, such as PKD1 gene, male gender and earlier age of onset. In Korea, ADPKD is a cause of ESRD in 2% of hemodialysis patients. Until now, only a few detailed studies have been performed in regarding to evaluate the risk factor for ESRD especially in the Asian population. 148 ADPKD patients were registered to PKD clinic in our hospital(Mar. 1996-Dec. 1999). Among them, 34 patients(male : female = 14 : 20) who had started renal replacement therapy were studied to elucidate clinical characteristics including the nature of progression of renal failure. These data were compared with 14 patients(male : female = 3 : 11) who did not develop renal failure(serum creatinine < OR =1.4 mg/dL) at the age of 50 years. Median age at the diagnosis of ADPKD was 43 years(range : 22-65 years), median age at initiation of renal replacement therapy(RRT) was 52.5 years(28-73) and median duration from the diagnosis to RRT were 6 years(0-30). The prevalence of gross hematuria, proteinuria (>1g/24h), urolithiasis, upper urinary tract infection, hypertension and liver cysts were 69, 54, 16, 29, 85 % and 85%, respectively. 84% of these patients had family members with ADPKD and 10% of them had ESRD family members. PKD1 vs. PKD2 was 7 : 1 in 8 patients with ESRD and 1 : 1 in 2 patients of control group. Gross hematuria and proteinuria were more prevalent in ESRD patients than the control group(p=0.001 and p=0.0008, respectively). In 18 patients with ESRD, rates of renal progression were traced using a reciprocal of serum creatinine(1/Cr) curve. Once azotemia(serum creatinine value > OR =1.5 mg/dL) developed, the median rate of decline of 1/Cr was -0.073dL/mg/year(range : -0.046--0.114dL/mg/year), which was constant irrespective of either the age of onset or sex. In summary, in 34 patients, the renal function seemed to be maintained to a certain age. But, once azotemia developed, the renal function was rapidly declining with similar rate, ended up ESRD in 8.2 years. Presence of gross hematuria and proteinuria were associated with poor prognosis.
Age of Onset ; Asian Continental Ancestry Group ; Azotemia ; Creatinine ; Diagnosis ; Female ; Hematuria ; Humans ; Hypertension ; Kidney Failure, Chronic* ; Korea ; Liver ; Male ; Polycystic Kidney Diseases ; Polycystic Kidney, Autosomal Dominant* ; Prevalence ; Prognosis ; Proteinuria ; Renal Dialysis ; Renal Insufficiency ; Renal Replacement Therapy ; Risk Factors ; Urinary Tract Infections ; Urolithiasis

PURPOSE: To evaluate the quality of prehospital CPR (cardiopulmonary resuscitation) performed by 119 rescue personnel and bystanders in Seoul and to recognize the present problems in the pre-hospital emergency medical service system (EMS). METHODS: We enrolled all patients in cardiac arrest visiting the emergency rooms of 9 university hospitals in Seoul via 119 rescue services from 16 October to 26 November 2006, prospectively investigating the environments in which arrest occurred and the factors associated with CPR. RESULTS: Among 73 patients, the most common place of arrest was in the home(45.2%), CPR by bystander was performed in 8 cases(10.7%), endotracheal intubation by EMS personnel was performed in 10 cases(14.1%). Average time from call to CPR was 11.9 minutes and the number of discharges alive was 3 cases(4.1%). CONCLUSION: To improve the rate of alive discharges, development of CPR education program for lay rescue, education in basic and advanced life support, and management of quality for EMS personnel are needed.
Cardiopulmonary Resuscitation ; Emergencies ; Emergency Medical Services ; Heart Arrest ; Hospitals, University ; Humans ; Hypogonadism ; Intubation, Intratracheal ; Mitochondrial Diseases ; Ophthalmoplegia ; Out-of-Hospital Cardiac Arrest ; Prospective Studies