MR Neurography: Current Several Issues for Novice Radiologists

Magnetic resonance neurography (MRN) has been increasingly used in recent years for the assessment of peripheral neuropathies. Fat suppression T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) have typically been used to provide high contrast MRN. Isotropic 3-dimensional (3D) sequences with fast spin echo, post-processing imaging techniques, and fast imaging methods, among others, allow good visualization of peripheral nerves that have a small diameter, complex anatomy, and oblique course within a reasonable scan time. However, there are still several issues when performing high contrast and high resolution MRN including standard sequence; fat saturation techniques; balance between resolution, field of view, and slice thickness; post-processing techniques; 2D vs. 3D image acquisition; different T2 contrasts between proximal and distal nerves; high T2 signal intensity of adjacent veins or joint fluid; geometric distortion; and appropriate p-values on DWI. The proper understanding of these issues will help novice radiologists evaluate peripheral neuropathies using MRN.

Ultrasonography of Malignant Clear Cell Hidradenoma: A Case Report

Clear cell hidradenoma is a tumor that originates from a sweat gland and typically involves the dermis and subcutaneous tissue. Malignant clear cell hidradenoma is very rare, and surgical excision is usually performed without imaging. There are few reports of the ultrasonographic findings of malignant clear cell hidradenomas. Herein, we present the ultrasonographic characteristics of a malignant clear cell hidradenoma.

Ultrasonography of Malignant Clear Cell Hidradenoma: A Case Report

Clear cell hidradenoma is a tumor that originates from a sweat gland and typically involves the dermis and subcutaneous tissue. Malignant clear cell hidradenoma is very rare, and surgical excision is usually performed without imaging. There are few reports of the ultrasonographic findings of malignant clear cell hidradenomas. Herein, we present the ultrasonographic characteristics of a malignant clear cell hidradenoma.

Parameters Affecting India Ink Artifacts on Opposed-Phase MR Images

PURPOSE: To determine the MR parameters affecting India ink artifacts on opposed-phase chemical shift magnetic resonance (MR) imaging.MATERIALS AND METHODS: The use of a female Sprague-Dawley rat was approved by our Institutional Animal Care and Use Committee. Using an iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) images, which is a modified Dixon method, axial opposed-phase images of the abdominal cavity were obtained with different MR parameters: series 1, different repetition times (TRs; 400, 2000, and 4000 ms); series 2, different echo times (TEs; 10, 50, and 100 ms); series 3, different field of views (FOVs; 6, 8, 16, and 24 cm); series 4, different echo train lengths (ETLs; 2, 4, and 8); series 5, different bandwidths (25, 50, and 85); and series 6, different slice thicknesses (1, 2, 4, 8, and 16 mm). Artifacts on opposed images obtained with different parameters were compared subjectively by two radiologists. For objective analysis, the thickness of the artifact was measured. Spearman's correlation between altered MR parameters and thicknesses of India ink artifact was obtained via objective analysis.RESULTS: India ink artifact was increasingly apparent using shorter TE, larger FOV and ETL, and thicker slices upon subjective analysis. The objective analysis revealed a strong negative correlation between the thickness of the artifact and TE (r = -0.870, P < 0.01); however, strong positive correlations were found between FOV (r = 0.854, P < 0.01) and slice thickness (r = 0.971, P < 0.01).CONCLUSION: India ink artifact was thicker with shorter TE, larger FOV, and larger slice thickness.

A Case of Thoracic Extradural Chordoid Meningioma: Focusing on Radiologic Features

Chordoid meningioma, an uncommon subtype of meningioma, occurs rarely in the spine. In this case report, the authors present a case of spinal chordoid meningioma in a young female patient, and include a detailed description of imaging findings and a literature review.

Effect of Hybrid Kernel and Iterative Reconstruction on Objective and Subjective Analysis of Lung Nodule Calcification in Low-Dose Chest CT

OBJECTIVE: To evaluate the differences in subjective calcification detection rates and objective calcium volumes in lung nodules according to different reconstruction methods using hybrid kernel (FC13-H) and iterative reconstruction (IR). MATERIALS AND METHODS: Overall, 35 patients with small (< 4 mm) calcified pulmonary nodules on chest CT were included. Raw data were reconstructed using filtered back projection (FBP) or IR algorithm (AIDR-3D; Canon Medical Systems Corporation), with three types of reconstruction kernel: conventional lung kernel (FC55), FC13-H and conventional soft tissue kernel (FC13). The calcium volumes of pulmonary nodules were quantified using the modified Agatston scoring method. Two radiologists independently interpreted the role of each nodule calcification on the six types of reconstructed images (FC55/FBP, FC55/AIDR-3D, FC13-H/FBP, FC13-H/AIDR-3D, FC13/FBP, and FC13/AIDR-3D). RESULTS: Seventy-eight calcified nodules detected on FC55/FBP images were regarded as reference standards. The calcium detection rates of FC55/AIDR-3D, FC13-H/FBP, FC13-H/AIDR-3D, FC13/FBP, and FC13/AIDR-3D protocols were 80.7%, 15.4%, 6.4%, 52.6%, and 28.2%, respectively, and FC13-H/AIDR-3D showed the smallest calcium detection rate. The calcium volume varied significantly with reconstruction protocols and FC13/AIDR-3D showed the smallest calcium volume (0.04 ± 0.22 mm³), followed by FC13-H/AIDR-3D. CONCLUSION: Hybrid kernel and IR influence subjective detection and objective measurement of calcium in lung nodules, particularly when both techniques (FC13-H/AIDR-3D) are combined.

Ultrasonographic Findings of Scleredema Adultorum of Buschke Involving the Posterior Neck

OBJECTIVE: To describe the clinical and ultrasonographic (US) findings in patients with scleredema adultorum of Buschke, who presented with sclerotic skin on their posterior neck. MATERIALS AND METHODS: After obtaining IRB approval, eight patients with scleredema adultorum of Buschke were enrolled. They underwent US examination of their posterior neck. The diagnoses were confirmed pathologically. The clinical history and US images were evaluated retrospectively. Dermal thickness was compared between the patient group and the age- and sex-matched control group. RESULTS: The patients included seven males and one female with a mean age of 51.5 years. All patients presented with thickening of the skin and/or a palpable mass on the posterior neck. Five (62.5%) of the eight patients showed erythematous discoloration. Six patients (75.0%) had a history of diabetes. The Hemoglobin A1c level was found to be increased in all patients. US images did not show any evidence of a soft tissue mass or infection. The mean dermal thickness in patients (7.01 ± 1.95 mm) was significantly greater than that in the control group (3.08 ± 0.87 mm) (p = 0.001). Multiple strong echogenic spots in the dermis were seen in all patients. Seven patients (87.5%) showed posterior shadowing in the lower dermis. CONCLUSION: When a patient with a history of diabetes presents with a palpable mass or erythematous discoloration of the posterior neck and US shows the following imaging features: 1) no evidence of a soft tissue mass or infection, 2) thickening of the dermis, 3) multiple strong echogenic spots and/or posterior shadowing in the dermis, scleredema adultorum of Buschke should be considered in the differential diagnosis.

Diabetic Amyotrophy Showing a Lesion in Lumbar Plexus MRI

No abstract available.

Changes in Tip-Apex Distance by Position and Film Distance Measured by Picture Archiving and Communication System (PACS) / 대한고관절학회지

PURPOSE: The tip-apex distance (TAD) is used to predict the clinical outcome of intertrochanteric fracture fixation. We aimed to measure the changes in TAD by position and film distance using Picture Archiving and Communication System (PACS). MATERIALS AND METHODS: We used a femur replica with a 10degrees femoral neck anteversion and a 130degrees neck shaft angle. Proximal femoral nail antirotation nail and a helical blade were inserted into the replica. Radiographs were taken at the neutral position and after applying 10degrees, 20degrees, 30degrees, 40degrees internal/external rotation, 10degrees abduction, and 10degrees and 40degrees adduction to the mechanical axis. Radiographs were taken at the replica-film distance of 10 cm and 20 cm under the same conditions, mimicking the differences in Focus-film distance (FFD), which reflect the patient's contour in clinical settings. A radiologist and an orthopedic surgeon measured the TAD twice using PACS. The average error was 2 mm (4.5%) and the standard error was +/-3.04. TADs in the neutral position constituted the standard values to measure the relative errors. RESULTS: TADs increased with an increase in the external rotation and abduction of the replica. TADs decreased with an increase in the internal rotation and adduction of the replica. For comparable measurements, relative errors were higher at FFDs of 20 cm compared to FFDs of 10 cm. CONCLUSION: Since the femur is internally rotated and adducted for reduction, orthopedic surgeons would assess the lag screw to be closer to the apex of femur on intraoperative radiographs. To have a correct measurement of the TAD after fixation of intertrochanteric fractures, radiographs should be taken in neutral position and measurement errors should be considered based on the patient's size.

Intra-Articular Fibroma of Tendon Sheath in a Knee Joint Associated with Iliotibial Band Friction Syndrome

Iliotibial band (ITB) friction syndrome is a common overuse injury typically seen in the active athlete population. A nodular lesion on the inner side of the ITB as an etiology or an accompanying lesion from friction syndrome has been rarely reported. A 45-year-old male presented with recurrent pain and a movable nodule at the lateral joint area, diagnosed as ITB friction syndrome. The nodule was confirmed as a rare intra-articular fibroma of the tendon sheath (FTS) on the basis of histopathologic findings. We describe the MRI findings, arthroscopic and pathologic features, in this case of intra-articular FTS presenting with ITB friction syndrome.

Does the ADC Map have Additional Clinical Significance Compared to the DWI in the Brain Infarction?

PURPOSE: To re-evaluate additional clinical significance of the apparent diffusion coefficient (ADC) map in the inference of infarction stage, authors studied the evolution patterns of the DWI and the ADC map of the brain infarction. MATERIALS AND METHODS: In 127 patients with cerebral infarctions, including follow-up checks, 199 studies were performed. They were classified as hourly (117 studies)-, daily (108 studies)-, weekly (62 studies)-based groups. The signal intensity (SI) was measured at the core of the infarction and contralateral area with ROI of 0.3 cm2 or more on the images of the DWI and the ADC map, and calculated the ratios of SI and ADC value of the infarction area / contralateral normal area, and compared the patterns of the change according to the evolution. RESULTS: Infarction was detected as early as 1 hour after the attack, and the ratio of SI in the DWI became over than 2 after 12 hours, which showed a plateau until the 6th day. Thereafter, it decreased slowly to 1 on the 30th day, and changed to lower SI than the surrounding brain. The ratio in the ADC map became 0.46 in 24 hours after the attack, and increased slowly to 1 in the 15th day. Thereafter, it became a higher value than the surrounding brain. Overall, the ratio in the ADC map changed earlier than in the DWI, and the ratio curves showed inverse pattern each other according to the evolution of the infarction. CONCLUSION: The evolution patterns of infarction on the ADC map showed an inverse curve of DWI curve, which means that the ADC value is accurately predictable from DWI, and the ADC map joined with the DWI seems helpful in the determination of subacute infarction between 15 to 30 days.

Application of 31P MR Spectroscopy to the Brain Tumors

OBJECTIVE: To evaluate the clinical feasibility and obtain useful parameters of 31P magnetic resonance spectroscopy (MRS) study for making the differential diagnosis of brain tumors. MATERIALS AND METHODS: Twenty-eight patients with brain tumorous lesions (22 cases of brain tumor and 6 cases of abscess) and 11 normal volunteers were included. The patients were classified into the astrocytoma group, lymphoma group, metastasis group and the abscess group. We obtained the intracellular pH and the metabolite ratios of phosphomonoesters/phosophodiesters (PME/PDE), PME/inorganic phosphate (Pi), PDE/Pi, PME/adenosine triphosphate (ATP), PDE/ATP, PME/phosphocreatine (PCr), PDE/PCr, PCr/ATP, PCr/Pi, and ATP/Pi, and evaluated the statistical significances. RESULTS: The brain tumors had a tendency of alkalization (pH = 7.28 +/- 0.27, p = 0.090), especially the pH of the lymphoma was significantly increased (pH = 7.45 +/- 0.32, p = 0.013). The brain tumor group showed increased PME/PDE ratio compared with that in the normal control group (p = 0.012). The ratios of PME/PDE, PDE/Pi, PME/PCr and PDE/PCr showed statistically significant differences between each brain lesion groups (p < 0.05). The astrocytoma showed an increased PME/PDE and PME/PCr ratio. The ratios of PDE/Pi, PME/PCr, and PDE/PCr in lymphoma group were lower than those in the control group and astrocytoma group. The metastasis group showed an increased PME/PDE ratio, compared with that in the normal control group. CONCLUSION: We have obtained the clinically applicable 31P MRS, and the pH, PME/PDE, PDE/Pi, PME/PCr, and PDE/PCr ratios are helpful for differentiating among the different types of brain tumors.

A Case of Man-in-the-Barrel Syndrome Induced by Cervical Spinal Cord Ischemia / 대한임상신경생리학회지

Man-in-the-barrel syndrome (MIBS) is a clinical syndrome of bilateral upper limb weakness with normal lower extremity function. It can be caused by various neurological conditions such as bilateral cerebral hypoperfusion, syringomyelia, motor neuron disease, or cervical myelopathies. We report a patient with MIBS after cervical spinal cord ischemia. It is postulated to be caused by ischemic insults of anterior spinal artery from repeated and prolonged neck extension.

Comparison of Diagnostic Performance of US Elastography and Conventional B-mode US in Differentiation of Breast Lesions

PURPOSE: The purpose of this study was to compare the diagnostic performance of ultrasound (US) elastography and conventional B-mode US for discrimination between benign and malignant breast lesions. MATERIALS AND METHODS: During a 13-month period, 277 women with 335 sonographically visible breast lesions who were scheduled to undergo biopsy were examined with US elastography. Elastographic findings were classified as benign or malignant based on the area ratio, with 1.00 as the threshold. Findings on conventional B-mode US were classified according to the BI-RADS category, as follows: lesions of BI-RADS categories 2 and 3 were considered benign, while those in categories 4 and 5 were considered malignant. Statistical analysis included sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and ROC curve analysis for comparison of the diagnostic performance of US elastography and conventional B-mode US. RESULTS: Of the 335 breast lesions, 85 (25.4%) showed malignancy on pathology. Findings on B-mode US showed malignancy in 264 (78.8%) and elastographic findings showed malignancy in 102 (30.4%). The sensitivity, specificity, PPV, NPV, and accuracy of B-mode US and elastography were 98.8%, 28.0%, 31.8%, 98.6%, and 79.4% and 69.4%, 81.2%, 57.8%, 88.8%, and 79.4%, respectively. Elastography showed significantly higher specificity and PPV and lower sensitivity and NPV, compared with B-mode US (p < 0.001). The area under the ROC curve (AUC value) was 0.761 for elastography, and 0.634 for B-mode US (p < 0.001). CONCLUSIONS: US elastography can improve specificity and PPV of B-mode US, but with significant sacrifice of sensitivity and NPV. Therefore, US elastography may complement B-mode US for differentiation of breast masses.

Comparison of Vascular Calcification Scores on Plain Radiographs to Predict Coronary Artery Disease According to Dialysis Modality / 대한신장학회지

PURPOSE: Vascular calcification (VC) scores on simple plain radiographic films are known to be associated with coronary artery disease (CAD) in hemodialysis (HD) patients. However, there is no report comparing VC scores on plain radiographic films according to dialysis modality. We hypothesized that there are some differences of VC scores on plain radiographs for the assessment of CAD according to dialysis modality. METHODS: We recruited 78 peritoneal dialysis (PD) patients and compared to 61 HD patients. We defined significant VC as any one finding among the abdominal aortic calcification (AAC) score > or =5, VC score of the hands and pelvis > or =3, or medial artery calcification of the feet on plain radiographs. RESULTS: The prevalence of CAD and significant VC were not different according to dialysis modality. Every VC score on the plain radiographs was highly correlated with each other, but VC evaluation on plain radiographs by single method overlooked nearly 30% of other significant VC sites in PD and HD patients. AAC score was most useful method for the prediction of CAD as a single VC scoring method. There was no association between VC of the feet and CAD in PD patients. Lower high density lipoprotein cholesterol was associated with significant VC on plain radiograph in PD patients. CONCLUSION: Significant VC formation on plain radiographs was not different according to dialysis modality. It is helpful to check several plain radiographs for the decision of CAD evaluation and not overlooking significant VC in both HD and PD patients.

The Age-related Microstructural Changes of the Cortical Gray and White Matter Ratios on T2-, FLAIR and T1-weighted MR Images

PURPOSE: The purpose of this study was to investigate the microstructural changes according to aging on the thickness and signal intensity (SI) of the cortical gray matter (GM) and white matter (WM) on the T2-, fluid-attenuated inversion recovery (FLAIR) and T1-weighted MR images in normal subjects. MATERIALS AND METHODS: The 10, 20, 30, 40, 50, 60, 70, 80 and 90 year age groups of men and women (each 10 individuals) who underwent routine brain MRI, including the T2-, FLAIR and T1-weighted images, were selected for this study. We measured the thickness and the SI of the cortical GM and WM at the postcentral gyrus, which has an even thickness at the level of centrum semiovale, on the axial scans and we calculated the mean values of the thickness ratio of the gray/white matter (TRGW) and the signal intensity ratio of the gray/white matter (SRGW), and we compared the ratios of each age group. RESULTS: On the T2-weighted images, the TRGWs were 0.81 and 0.79 at the age of 10 and they were 0.73 and 0.71 at the age of 90 in the men and women, respectively. So, the GM thickness was decreased more than the WM thickness was with aging. On the FLAIR images, the TRGWs were 1.09 and 1.00 at the age of 10 and they were 1.11 and 0.95 at the age of 70 in the men and women, respectively. On the T1-weighted images, the TRGWs were 0.66 and 0.80 at the age of 10, and the ratio was changed to 0.90 and 0.78 at the age of 90 in the men and women, respectively. On the T2-weighted image, the SRGWs were 1.53 and 1.43 at the age of 10, and they were 1.23 and 1.27 at the age of 90 in the men and women, respectively. On the FLAIR images, the SRGWs were 1.23 and 1.25 at the age of 10 and they were 1.06 and 1.05 at the age of 90 in the men and women, respectively. On the T1-weighted images, the SRGWs were 0.86 and 0.85 at the age of 10, and they were 0.90 and 0.87 at the age of 90 in the men and women, respectively. CONCLUSION: We suggest that the age-related microstructural changes of the thickness and the SI of the cortical GM and WM on the T2-, FLAIR and T1-weighted images are unique, and so this knowledge will be helpful to differentiate neurodegenerative disease from normal aging of the brain.

The Age-related Microstructural Changes of the Cortical Gray and White Matter Ratios on T2-, FLAIR and T1-weighted MR Images

PURPOSE: The purpose of this study was to investigate the microstructural changes according to aging on the thickness and signal intensity (SI) of the cortical gray matter (GM) and white matter (WM) on the T2-, fluid-attenuated inversion recovery (FLAIR) and T1-weighted MR images in normal subjects. MATERIALS AND METHODS: The 10, 20, 30, 40, 50, 60, 70, 80 and 90 year age groups of men and women (each 10 individuals) who underwent routine brain MRI, including the T2-, FLAIR and T1-weighted images, were selected for this study. We measured the thickness and the SI of the cortical GM and WM at the postcentral gyrus, which has an even thickness at the level of centrum semiovale, on the axial scans and we calculated the mean values of the thickness ratio of the gray/white matter (TRGW) and the signal intensity ratio of the gray/white matter (SRGW), and we compared the ratios of each age group. RESULTS: On the T2-weighted images, the TRGWs were 0.81 and 0.79 at the age of 10 and they were 0.73 and 0.71 at the age of 90 in the men and women, respectively. So, the GM thickness was decreased more than the WM thickness was with aging. On the FLAIR images, the TRGWs were 1.09 and 1.00 at the age of 10 and they were 1.11 and 0.95 at the age of 70 in the men and women, respectively. On the T1-weighted images, the TRGWs were 0.66 and 0.80 at the age of 10, and the ratio was changed to 0.90 and 0.78 at the age of 90 in the men and women, respectively. On the T2-weighted image, the SRGWs were 1.53 and 1.43 at the age of 10, and they were 1.23 and 1.27 at the age of 90 in the men and women, respectively. On the FLAIR images, the SRGWs were 1.23 and 1.25 at the age of 10 and they were 1.06 and 1.05 at the age of 90 in the men and women, respectively. On the T1-weighted images, the SRGWs were 0.86 and 0.85 at the age of 10, and they were 0.90 and 0.87 at the age of 90 in the men and women, respectively. CONCLUSION: We suggest that the age-related microstructural changes of the thickness and the SI of the cortical GM and WM on the T2-, FLAIR and T1-weighted images are unique, and so this knowledge will be helpful to differentiate neurodegenerative disease from normal aging of the brain.

Mechanism of Amelioration of Cisplatin Nephrotoxicity by Procaine Treatment in Mice / 대한마취과학회지

BACKGROUND: Procaine binds to DNA and reduces cisplatin nephrotoxicity, but the mechanism is poorly understood. We explored whether procaine amelioration of cisplatin nephrotoxicity was related to down-and/or up-regulation of inflammatory response gene tumor necrosis factor-alpha (TNF-alpha), oxidative stress indicator gene heme oxygenase-1 (HO-1) or cell cycle inhibitor gene p21. METHODS: Cisplatin and procaine were intraperitoneally injected to mice at a single dosage of 16 and 80 mg/kg, respectively. Renal evaluation was performed 72 hours after cisplatin administration. The expression of transcripts and proteins was analyzed using real time RT-PCR and Western blot, respectively. RESULTS: Procaine treatment moderately attenuated necrotic changes of renal proximal tubules and increases in BUN and creatinine concentration by cisplatin administration. Kidney platinum level between the cisplatin (cis) group and the cisplatin + procaine (CisPro) group was not different. Although the level of TNF-alpha mRNA increased 4-fold higher in the Cis group than in the control, this increase was not attenuated by procaine treatment. Gene expression of p21 and HO-1 was elevated 175 and 4-times higher in the Cis group than in the control, respectively. But their expression was no further elevated, rather significantly reduced in the CisPro group compared to the Cis group. Protein abundance of p21 and HO-1 was paralleled by their respective mRNA expression. CONCLUSIONS: Procaine amelioration of cisplatin nephrotoxicity is likely to be achieved through processes other than the regulation of TNF-alpha, HO-1 or p21 gene expression.

Benign Mass after Reduction Mandibular Angleplasty

There have been various methods of reduction mandibular angleplasty. 21-year old woman with prominent mandibular angle and body was done curved angle ostectomy with tangential ostectomy. In operation, we had used bone wax for controlling of bone bleeding. After 1 year, the patient revisited to our clinic because she had a mass with tenderness on Lt. mandibular angle area. The mass had been gradually increasing in severity after reduction mandibular angleplasty. Computed tomography of the patient showed inflammatory lesion in Lt. mandibular angle area with focal cortical bony destruction and adjacent soft tissue thickening. After surgical removal of mass, clinical pathology revealed that the mass was chronic inflammatory fibrosis around foreign body(bone wax). The postoperative course was uneventful, the patient was satisfied for her shape. If possible we must avoid using a bone wax in reduction mandibular angleplasty, because bone wax can induce inflammatory reaction and fibrosis.

A Case of Nevus Sebaceus associated with Syringocystadenoma Papilliferum, Trichoblastoma, Basal Cell Carcinoma, Sebaceous Adenoma and Sebaceous Epithelioma / 대한피부과학회지

Nevus Sebaceus is a hamartoma that has a well-documented neoplastic potential. Multiple tumors may occasionally arise, but the coexistence of 3 or more tumors is extremely rare. We report a case of nevus sebaceus in a 55-year-old female associated with syringocystadenoma papilliferum, trichoblastoma, basal cell carcinoma, sebaceous adenoma and sebaceous epithelioma.