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Objectives: The long-term durability of carotid artery stenting (CAS) may be determined by various factors; however, residual stenosis is a known risk factor for in-stent restenosis. The authors of this article utilized cone-beam computed tomography (CBCT) in angiosuite to investigate plaque features affecting the character and quality of stent expansion after CAS., Methods: Forty-two CAS cases with both pre- and post-CAS CBCT evaluations were included in this retrospective analysis. Five features derived from pre-CAS images were tested: (1) eccentricity, (2) overballoon, (3) maximum plaque thickness, (4) calcification barrier, and (5) stenotic degree. For post-CAS CBCT, stent configuration was assessed if the stent was expanded and oval or round in shape as well as outward or inward in orientation. Variables were tested if they were associated with oval expansion, outward expansion, and 20% residual stenosis after CAS., Results: Oval or outward expansion is directly related to residual stenosis. The oval expansion was associated with maximum plaque thickness, and outward expansion was associated with the presence of a calcification barrier. Variables related to > 20% residual stenosis were the maximum plaque thickness, calcification barrier, and pre-CAS stenotic degree., Conclusions: CBCT for carotid stenosis may provide valuable information about plaque features, especially calcification features that may interfere with the angioplasty effect, as well as the characteristics and quality of stent expansion. Residual stenosis > 20% was associated with calcification barrier, maximum plaque thickness, and pre-CAS stenotic degree., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Various diseases can affect the esophagus. Endoscopic ultrasound (EUS), which provides precise information about the layers of the esophageal wall, is the primary approach used to investigate esophageal diseases. However, CT is one of the most important imaging modalities for diagnosing esophageal diseases as it can elucidate mediastinal involvement, adjacent lymphadenopathy, and distant disease spread. These two modalities complement each other in the diagnosis of esophageal diseases. Although radiologists may be unfamiliar with EUS procedures and their interpretation, understanding them aids in the differential diagnosis of esophageal conditions. This pictorial essay illustrates the EUS and CT findings of various esophageal diseases originating in the esophageal wall., Competing Interests: Conflicts of Interest: The authors have no potential conflicts of interest to disclose., (Copyrights © 2024 The Korean Society of Radiology.)

Background: Chest computed tomography (CT) is routinely performed to evaluate intrathoracic metastasis in patients with breast cancer, but radiation exposure and its potential carcinogenic risks are major drawbacks. Furthermore, pulmonary imaging by magnetic resonance imaging (MRI) is limited by low proton density, rapid signal decay, and sensitivity to respiratory and cardiac motions in lung tissue. Recently, a respiratory gating spiral three-dimensional (3D) ultrashort echo time (UTE) volume interpolated breath-hold examination (VIBE) sequence for lung MRI provides high spatial-resolution images with reasonable scan times. Our objective was to investigate the feasibility of chest spiral 3D UTE VIBE MRI to detect intrathoracic metastasis in breast cancer patients., Methods: This retrospective study of a prospectively collected database was conducted between February and July 2019 after institutional review board approval. All participants provided informed consent for MRI scans. Ninety-three female patients with breast cancer were retrospectively enrolled and underwent preoperative breast MRI, including a chest spiral 3D UTE VIBE sequence. Two chest radiologists evaluated image qualities of intrapulmonary vessels and bronchial wall visibilities, the presence of pulmonary nodules, significant lymph nodes (LNs), and other lung abnormalities on spiral 3D UTE magnetic resonance (MR) images and compared them using chest CT as a reference standard., Results: Intrapulmonary vessels and bronchial walls were visible up to sub-subsegmental and sub-subsegmental levels, respectively, on spiral 3D UTE MR images, and better than fair quality was obtained for artifact/noise and overall image quality for 95.7% and 98.9% of the patients, respectively. The overall detection rate for pulmonary nodules was 62.8% (59/94). Furthermore, 59 of the 81 solid nodules detected by CT were detected by spiral 3D UTE MRI (72.8%), and 31 of the 33 solid nodules (≥5 mm in diameter) detected by CT were identified by spiral 3D UTE MRI (93.9%). Significant LNs in the axillary area were similarly detected by spiral 3D UTE MRI and chest CT., Conclusions: Preoperative breast MRI with a chest spiral 3D UTE sequence could be used to evaluate breast cancer and axillary LNs and intrathoracic metastasis simultaneously and offers a potential alternative to chest CT for breast cancer patients without additional radiation exposure., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1006/coif). YJJ repots a 2-Year Research Grant from Pusan National University. The other authors have no conflicts of interest to declare., (2023 Journal of Thoracic Disease. All rights reserved.)

A ruptured brain arteriovenous malformation (bAVM) presenting with a hematoma may have unseen parts of the shunts in diagnostic angiography in the acute phase, which may lead to innate incomplete evaluation for the whole angioarchitecture of the bAVM. Even though it is generally accepted that the nidus of a ruptured bAVM may be underestimated in angiography during the acute phase due to hematoma compression, documentation of the underestimated parts has not been described in the literature. The authors report 2 cases of ruptured bAVMs in which the obscured segments were cast with liquid embolic material, which suggests a potential presence of obscured segments in bAVMs.

Simple renal cysts are the most common masses in the kidney. Most are asymptomatic and are incidentally detected on imaging examinations performed for other reasons. This study aimed to compare the results of 40 and 120 minutes ethanol sclerotherapies that were performed in a single session to treat incidentally found simple renal cysts. We retrospectively reviewed 63 renal cysts in 62 patients treated by single session percutaneous ethanol sclerotherapy. Thirty-one patients with 32 cysts underwent a 40 minutes sclerotherapy (group A), and 31 patients with 31 cysts underwent a 120 minutes retention technique (group B). Under ultrasonographic and fluoroscopic guidance, cystic fluid was completely aspirated, and 50% of the aspirated volume was replaced with 99.5% ethanol (a maximum of 100 mL). Imaging follow-up of the patients was performed 3 months after sclerotherapy. The technical success rates were 100% in both groups. Eighteen patients (29.0%) were symptomatic (flank pain or discomfort). Indications of the other patients were large cysts (>5 cm; 46%) and an increment in the diameter on serial studies (25.4%). A significant difference between the 2 groups in terms of age, cyst diameter, volume of aspirated fluid, volume of injected ethanol, and percentage of reduction in cyst diameter (P > .05) was not found. After treatment, flank pain or discomfort resolved in 17 of 18 (94.4%) symptomatic patients. One patient complained of persistent flank pain; however, no significant abnormality was detected on post-procedural computed tomography images. There were no other complications after therapy in the 2 groups. Single session ethanol sclerotherapy with a 40 minutes retention technique is an effective, safe, and cost-effective method for the treatment of incidentally found simple renal cysts. Although the procedural time was reduced, there was no significant difference in therapeutic efficacy between the 40 and 120 minutes therapies., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

The authors report a rare case of sequentially developed bilateral internal carotid artery (ICA) fusiform giant aneurysms in a patient with pathologically confirmed intimal fibroplasia. Both ICA fusiform aneurysms were treated with multiple flow diverter insertion and were well-managed over the past 5.5 years of follow-up. The development of aneurysms in this rare disease entity appears to be a lifelong process based on the authors' observations in serial angiographic follow-up studies. Reconstruction therapy using flow-diverting stents in this unique condition may be a safe and effective treatment modality.

Backgroundand Objectives: To date, imaging characterization of non-rheumatic retro-odontoid pseudotumors (NRROPs) has been lacking; therefore, NRROPs have been confused with atlantoaxial joint involvement of rheumatoid arthritis (RA). It is important to differentiate these two disease because the treatment strategies may differ. The purpose of this study is to characterize imaging findings of NRROPs and compare them with those of RA. Material and Methods: From January 2015 to December 2019, 27 patients (14 women and 13 men) with NRROPs and 19 patients (15 women and 4 men) with RA were enrolled in this study. We evaluated various imaging findings, including atlantoaxial instability (AAI), and measured the maximum diameter of preodontoid and retro-odontoid spaces with magnetic resonance imaging (MRI) and computed tomography (CT). Results: Statistical significance was considered for p < 0.05. AAI was detected in eight patients with NRROPs and in all patients with RA (p < 0.0001). Seventeen patients with NRROPs and six patients with RA showed spinal cord compression (p = 0.047). Compressive myelopathy was observed in 14 patients with NRROPs and in 4 patients with RA (p = 0.048). Subaxial degeneration was observed in 25 patients with NRROPs and in 9 patients with RA (p = 0.001). Moreover, C2-3 disc abnormalities were observed in 11 patients with NRROPs and in 2 patients with RA (p = 0.02). Axial and longitudinal diameter of retro-odontoid soft tissue and preodontoid and retro-odontoid spaces showed significant differences between NRROP and RA patients (p < 0.0001). Furthermore, CT AAI measurements were differed significantly between NRROP and RA patients (p < 0.05). Conclusions: NRROPs showed prominent retro-odontoid soft tissue thickening, causing compressive myelopathy and a high frequency of subaxial and C2-3 degeneration without AAI.

Background: A malignant melanotic nerve sheath tumor (MMNST), previously known as a melanotic schwannoma, is a rare variant of a peripheral nerve sheath tumor composed of Schwann cells with melanotic differentiation. Only a few reports of spinal MMNST have been reported., Case Summary: In the first case, a 58-year-old woman presented with a history of low back pain and paresthesia. Magnetic resonance imaging (MRI) and computed tomography (CT) of the lumbar spine revealed an intradural extramedullary mass lesion with amorphous linear calcification. Complete tumor resection was performed and histological examination revealed a psammomatous melanotic schwannoma. In the second case, a 72-year-old man presented with low back pain and paresthesia. MRI of the thoracolumbar spine revealed an intramedullary mass lesion at the T11 vertebral body level. The mass lesion was hypointense on T2WI and hyperintense on T1WI. Tumor resection was performed and the histologic result was melanotic schwannoma., Conclusion: MMNST should be considered in the differential diagnosis when calcification or melanin is seen in an intradural spinal tumor., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background and Objectives: Although reducing the radiation dose level is important during diagnostic computed tomography (CT) applications, effective image quality enhancement strategies are crucial to compensate for the degradation that is caused by a dose reduction. We performed this prospective study to quantify emphysema on ultra-low-dose CT images that were reconstructed using deep learning-based image reconstruction (DLIR) algorithms, and compared and evaluated the accuracies of DLIR algorithms versus standard-dose CT. Materials and Methods: A total of 32 patients were prospectively enrolled, and all underwent standard-dose and ultra-low-dose (120 kVp; CTDIvol < 0.7 mGy) chest CT scans at the same time in a single examination. A total of six image datasets (filtered back projection (FBP) for standard-dose CT, and FBP, adaptive statistical iterative reconstruction (ASIR-V) 50%, DLIR-low, DLIR-medium, DLIR-high for ultra-low-dose CT) were reconstructed for each patient. Image noise values, emphysema indices, total lung volumes, and mean lung attenuations were measured in the six image datasets and compared (one-way repeated measures ANOVA). Results: The mean effective doses for standard-dose and ultra-low-dose CT scans were 3.43 ± 0.57 mSv and 0.39 ± 0.03 mSv, respectively (p < 0.001). The total lung volume and mean lung attenuation of five image datasets of ultra-low-dose CT scans, emphysema indices of ultra-low-dose CT scans reconstructed using ASIR-V 50 or DLIR-low, and the image noise of ultra-low-dose CT scans that were reconstructed using DLIR-low were not different from those of standard-dose CT scans. Conclusions: Ultra-low-dose CT images that were reconstructed using DLIR-low were found to be useful for emphysema quantification at a radiation dose of only 11% of that required for standard-dose CT.

Background: Chest radiography value as a screening tool in those exposed to pulmonary tuberculosis (TB) is reduced by its lower sensitivity to detect small intrapulmonary lesions., Purpose: To evaluate the efficacy of digital tomosynthesis (DTS) screening of individuals that had contacted persons with active TB using low-dose computed tomography (CT) as the reference standard methods., Material and Methods: This retrospective, community-based screening study of 90 adults who had been in close contact with a TB case was undertaken at our institution. All individuals underwent clinical evaluation, digital radiography (DR), DTS, and low-dose chest CT. Observers assessed and classified DR and DTS images using CT as the reference-standard method. Based on clinical and imaging findings, TB status was classified as normal, latent, minimal, subclinical, and active. Diagnostic performances of DTS and DR for the interpretation of correct diagnosis were calculated., Results: The estimated effective doses for DR, DTS, and low-dose CT were 0.01 mSv, 0.1 mSv, and 0.33 mSv, respectively. TB statuses of the 90 individuals were as follows: 62 latent (68.9%); two subclinical (2.2%); and one minimal (1.1%). The sensitivities, specificities, and accuracies of DTS and DR in the interpretation of correct diagnosis were 75.8%, 100%, 91.1% and 48.5%, 96.5%, 78.9%, respectively., Conclusion: DTS appears to be superior to DR for the detection of lung lesions in individuals with TB contacts. DTS can offer a reasonable option for TB contact investigation.

Acute phlegmonous esophagitis is a very rare, life-threatening form of esophagitis, characterized by diffuse bacterial infection and pus formation within the submucosal and muscularis layers of the esophagus. We describe a case in which contrast-enhanced chest CT was useful for evaluating the severity of phlegmonous esophagitis, which was overlooked and underestimated by endoscopy.

Background and Objectives: Glomus tumors are rare benign tumors. The majority of them affect the skin the most and are rarer in the trachea, where the glomus bodies may not be present. Only scarce reports of tracheal glomus tumors have been reported solely with case reports of relevant articles., Materials and Methods: A 53-year-old man, with a free previous medial history, presented to our hospital with tracheal mass which was incidentally found. He did not complain of any specific symptoms associated with the tracheal tumor. The contrast-enhanced chest computed tomography (CT) revealed an avid enhancing nodular lesion, which is similar to blood vessels, in the trachea, 3 cm above the carina level without definite airway obstruction., Results: Successful tracheal resection and end-to-end anastomosis were performed on the patients; therefore, the final post-operative pathologic findings revealed a benign tracheal glomus tumor. The follow-up CT scan four months after operation showed complete removal of the tumor., Conclusion: Tracheal glomus tumors, even rare entities, could be considered as a differential diagnosis if a highly enhancing mass appears on CT images.

Purpose: There are many studies on sentinel lymph node (SLN) biopsy in thyroid carcinoma but SLN biopsy (SLNB) in papillary thyroid carcinoma (PTC) remains open to debate. Therefore in this retrospective study, the usefulness of SLNB in thyroid carcinoma patients who had micro-PTC without cervical lymphadenopathy was assessed., Methods: SLNB was performed in 114 patients who were diagnosed with micro-PTC in a single lobe without palpable or ultrasound-detected lymph node at the tertiary center between January 2012 and December 2013. After SLNB, all patients underwent total thyroidectomy and central neck dissection or thyroid lobectomy and central neck dissection of the single side., Results: SLNs were identified in 112 of 114 patients with 41 positive SLNs and 71 negative SLNs on intraoperative frozen sections. However, eight negative patients were found to be positive in the final pathology. Sentinel node identification rate and false negative value of SLNB were 98.2% and 11.3%, respectively. In the univariate analysis, higher lymph node metastasis was detected in men than in women. Higher detection number of SLN showed higher probability of lymph node metastasis., Conclusion: SLNB may be helpful in papillary thyroid cancer, especially in male patients. Also, it is useful for the staging of nodal status and clearance of persistent disease., Competing Interests: No potential conflict of interest relevant to this article was reported., (Copyright © 2021 Korean Society of Surgical Oncology.)

Purpose: The balloon-stent technique (BST) has certain strengths as an assisted technique for the treatment of complex aneurysms. After Atlas release, the BST can be executed without an exchange maneuver of the balloon to the stent-delivery catheter. The purpose of this article is to share our experience with the BST using the Scepter-Atlas combination., Materials and Methods: Device inspection led us to a simple method to avoid failure in loading Atlas to the Scepter. From March 2018 to December 2019, 57 unruptured distal internal carotid artery (dICA) aneurysms were treated with coil embolization; among which, 25 aneurysms in 23 patients were treated with BST. Clinical and angiographic data were retrospectively collected and reviewed., Results: The technical success rate of the Scepter-Atlas combination increased from 50% to 100% after careful inspection. BST angiographic results were comparable to the stent-assisted coil (SAC) group treated during the immediately post-embolization same period (modified Raymond-Roy classification [MRRC] 1 & 2 84% in BST, 96.3% in SAC) and during short-term follow-up (MRRC 1 & 2 95.8% in BST, 88.4% in SAC). A small number of patients showed periprocedural complications, but none had clinical consequences., Conclusion: BST using the Scepter-Atlas combination can provide an effective and safe method for the treatment of dICA aneurysms. Scepters can be used as delivery catheters for Atlas., Competing Interests: Conflicts of Interest: The authors have no potential conflicts of interest to disclose., (Copyrights © 2021 The Korean Society of Radiology.)

Purpose: To investigate the MRI features associated with neural foraminal stenosis (NFS) in patients older than 60 years with lumbar (L) radiculopathy., Materials and Methods: This study included 133 retrospectively selected patients older than 60 years with lumbar radiculopathy who had undergone a lumbar spine MRI (from January 2018 to April 2018). For L4/L5 and L5/sacral (S)1 levels, NFS was reviewed blindly by two radiologists. Spondylolisthesis, retrolisthesis, disc height loss, disc bulging/herniation/central canal stenosis, ligamentum flavum thickening, and facet hypertrophy were evaluated separately for the NFS and non-NFS groups, and they were compared using univariate and multivariate analyses., Results: The univariate analysis revealed that disc height loss ( p = 0.006) was associated with NFS for L4/L5. For L5/S1, both spondylolisthesis ( p = 0.005) and facet hypertrophy ( p = 0.006) were associated with NFS. The multivariate logistic analysis revealed that disc height loss was associated with NFS for L4/L5 [odds ratio (OR) = 4.272; 95% confidence interval (CI) 1.736-10.514]. For L5/S1, spondylolisthesis (OR = 3.696; 95% CI 1.297-10.530) and facet hypertrophy (OR = 6.468; 95% CI 1.283-32.617) were associated with NFS., Conclusion: Disc height loss was associated with NFS for L4/L5 and spondylJophy were associated with NFS for L5/S1., Competing Interests: Conflicts of Interest: Chang Ho Jeon has been an Editorial Board Member of Journal of the Korean Society of Radiology since 2021; however, he was not involved in the peer reviewer selection, evaluation, or decision process of this article. Otherwise, no other potential conflicts of interest relevant to this article were reported., (Copyrights © 2021 The Korean Society of Radiology.)

Purpose: Some patients with neonatal seizures show diffuse, symmetric diffusion-restricted lesions in the cerebral white matter. The aim of this study was to describe clinical and imaging findings of patients with neonatal seizures who had diffuse, symmetric diffusion-restricted lesions without any structural or metabolic etiology., Materials and Methods: A total of 56 neonates aged less than 1 week underwent brain magnetic resonance imaging (MRI) for evaluation of seizures from November 2008 to February 2017. After excluding 43 patients, 13 patients showed diffuse white matter abnormality on diffusion-weighted imaging. Initial and follow-up clinical and MRI findings were analyzed retrospectively., Results: All 13 patients were born at full term. Among the ten patients who underwent a stool test for viruses, six were positive for rotavirus and one for astrovirus. MRI revealed diffuse, symmetric diffusion-restricted lesions distributed along the cerebral white matter, thalami, and midbrain variably., Conclusion: Diffuse, symmetric diffusion-restricted lesions involving the cerebral white matter can be seen in patients with neonatal seizures without any structural or metabolic etiology. Rotavirus is commonly but not exclusively detected in these patients. Nevertheless, viral infection-associated encephalopathy should be considered for patients with characteristic clinical and MRI findings., Competing Interests: Conflicts of Interest: The authors have no potential conflicts of interest to disclose., (Copyrights © 2020 The Korean Society of Radiology.)

Purpose: The aim of this study was to identify the factors affecting the prognosis of children with foreign body aspiration (FBA) after undergoing rigid bronchoscopy., Methods: This was a case series with a chart review of 49 children under 3 years of age who underwent rigid bronchoscopy for suspected FBA at a single tertiary institution., Results: The time from symptom onset to hospitalization positively correlated with the total hospitalization time (p < 0.001), postoperative hospitalization time (p = 0.006), and operation time (p = 0.013). The time from symptom onset to operation positively correlated with the total hospitalization time (p < 0.001) and operation time (p = 0.046). The time from hospitalization to operation and the operation time positively correlated with the total hospitalization time (p = 0.026, 0.044) and postoperative hospitalization time (p = 0.049, 0.003). The time from symptom onset to hospitalization positively correlated with the incidence of pneumonia (p = 0.028)., Conclusion: Rapid hospitalization after symptom onset, rapid surgery after symptom onset, and rapid surgery after hospitalization improve the prognosis of patients with FBA. Further, a short operation time also plays a role in improving patient prognosis.

Background: The safety of gadolinium-based contrast agents is of fundamental importance., Purpose: To determine the frequency and severity of immediate-type adverse reactions to approved doses of gadoteridol in patients referred for routine gadoteridol-enhanced MRI in actual clinical practice settings., Study Type: Prospective, observational., Population: In all, 6163 subjects were enrolled (mean age: 56.7 ± 15.4 years; range: 6-93 years)., Field Strength/sequence: 1.5T and 3.0T., Assessment: Assessment was of immediate adverse reactions by the investigating radiologist using the MedDRA System Organ Class and preferred term., Statistical Tests: Summary statistics for continuous variables, descriptive statistics for demographic characteristics., Results: Overall, 19 adverse events occurred in 13 (0.21%) patients, of which 15 in 10 (0.16%) patients were considered related to gadoteridol administration. These events were evenly distributed between male and female subjects and all occurred in adults. Twelve of the 15 related events in eight (0.13%) patients were considered mild in intensity (rapidly self-resolving), while the remaining three events in two patients (0.03%) were considered moderate in intensity. None were of severe intensity and no serious adverse events occurred., Data Conclusion: The rate of immediate-type adverse events following exposure to approved doses of gadoteridol is extremely low, and mostly limited to transient and self-resolving symptoms., Level of Evidence: 2 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2020;51:861-868., (© 2019 The Authors. Journal of Magnetic Resonance Imaging published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.)

Background and Purpose: Carotid artery stent placement is widely performed for treatment of carotid stenosis. The purpose of this study is to present our observations on cerebral vasoconstriction in ipsilateral anterior circulation during immediate poststenting angiography in patients with near-total occlusion of the proximal ICA., Materials and Methods: We retrospectively reviewed patient data from December 2008 to December 2018. There were 28 patients with carotid near-total occlusion. Two neuroradiologists reviewed the final cerebral angiographic finding of carotid artery stent placement to evaluate the presence of vasoconstriction or vasodilation., Results: A total of 28 patients with near-total occlusion (mean ± standard deviation age, 69.0 ± 6.5 years; 92.9% male) were analyzed. Ten patients showed vasoconstriction in the treated territory, and 18 patients did not show vasoconstriction after carotid artery stenting. There were no statistically significant differences in comorbidity, frequency of symptomatic lesions, antiplatelet medication, mean procedure time, and initial NIHSS and baseline modified Rankin scale scores between the 2 groups. However, vasoconstriction is more likely to happen in patients with isolated territory from the contralateral anterior and posterior circulation (66.7% in the isolated territory group and 12.5% in the not-isolated territory group; P  < .05). No headache or neurologic deficit was noted in all 10 patients with cerebral vasoconstriction., Conclusions: Cerebral vasoconstriction may occur after carotid artery stenting more frequently than expected. It occurs more frequently in patients with near-total occlusion and with isolation of the cerebral circulation. A large-scale study is necessary to assess the clinical implications of cerebral vasoconstriction after carotid artery stenting., (© 2020 by American Journal of Neuroradiology.)

Objective: Although CT has been used as a complementary diagnostic method for the preoperative diagnosis of thyroid cancer, it has the shortcomings of substantial radiation exposure and the use of contrast material (CM). The purpose of this article is to evaluate the image quality and diagnostic performance of 70-kVp thyroid CT with low volumes of CM versus conventional 120-kVp thyroid CT protocol., Materials and Methods: Eighty patients referred for preoperative thyroid CT were randomly divided into two groups (group A: 40 patients, 70 kVp, 60 mL of CM; group B: 40 patients, 120 kVp, 100 mL of CM). Quantitative and qualitative image quality and radiation doses for the two groups were compared using the Mann-Whitney U and chi-square tests. Degrees of agreement between preoperative CT staging and pathologic results were evaluated and compared using the Wald statistic., Results: Calculated signal-to-noise ratios of different anatomic structures, calculated contrast-to-noise ratios, overall image quality, subjective noise, and streak artifacts were not significantly different between the two groups (all p > 0.05), and neither were the accuracies of preoperative CT staging (all p > 0.05). The estimated effective doses were significantly lower in group A (mean [± SD], 0.52 ± 0.14 mSv in group A and 2.28 ± 0.29 mSv in group B; p < 0.001)., Conclusion: Ultra-low-dose 70-kVp CT with a low volume of CM provides sufficient image quality for preoperative staging of thyroid cancer and substantially reduces the radiation dose compared with standard 120-kVp CT.

Purpose: This study evaluated the feasibility of acoustic radiation force impulse (ARFI) elastography and characterized the sonographic features of lymph nodes (LNs) with Kikuchi disease in pediatric patients., Methods: Seventy-six cervical LN biopsies were performed for the diagnosis of cervical lymphadenopathy. ARFI imaging was performed, and the characteristic ultrasound features of the biopsied LNs and the contralateral LNs were analyzed. We also reviewed clinical and conventional ultrasonographic findings., Results: On histology, 56 patients were diagnosed with Kikuchi disease. These LNs were large and elongated, with increased perinodal echogenicity and capsular thickening. In 38 of them, ARFI elastography was performed, and the median shear wave velocity (SWV) of the biopsied LNs with Kikuchi disease (2.19 m/sec; range, 1.45 to 4.57 m/sec) was higher than of the contralateral LNs (1.72 m/sec; range, 0.95 to 2.65 m/sec; P<0.001). In patients with reactive hyperplasia, the mean SWV of the biopsied LNs (2.00 m/sec; range, 1.49 to 2.26 m/sec) was higher than that of the contralateral LNs (1.55 m/sec; range, 1.21 to 2.32 m/sec; P=0.031)., Conclusion: The SWV of LNs with Kikuchi disease was significantly higher than that of the contralateral LNs. Morphologically, LNs with Kikuchi disease showed an enlarged, elongated, and oval shape, increased perinodal echogenicity, and capsular thickening. In addition to the conventional ultrasonographic findings, the application of ARFI is feasible even in pediatric patients for the evaluation of cervical lymphadenopathy.

Gastric tuberculosis accounts for approximately 2% of all cases of gastrointestinal tuberculosis. Diagnosis of gastric tuberculosis is challenging because it can present with various clinical, endoscopic, and radiologic features. Tuberculosis manifesting as a gastric subepithelial tumor is exceedingly rare; only several dozen cases have been reported. A 30-year-old male visited emergency room of our hospital with hematemesis and melena. Abdominal CT revealed a 2.5 cm mass in the gastric antrum, and endoscopy revealed a subepithelial mass with a visible vessel at its center on gastric antrum. Primary gastric tuberculosis was diagnosed by surgical wedge resection. We report a rare case of gastric tuberculosis mimicking a subepithelial tumor with acute gastric ulcer bleeding.

Orbital implants are commonly used to repair orbital blowout fractures, to restore the functional and anatomical structure of the orbit. Porous polyethylene implants are a type of alloplastic implant and are widely used for orbital reconstruction as micropores facilitate the growth of fibers and blood vessels through the material. Rare complications associated with porous polyethylene implants used to treat blowout fractures include delayed orbital inflammation and osteomyelitis. The authors describe a 68-year-old man who presented with a 5-year delayed porous polyethylene implant infection and cicatricial ectropion with osteomyelitis after an orbital blowout fracture repair. The patient underwent surgery to incision and drainage of orbital abscess with ectropion correction surgery. He was treated with intravenous antibiotics for 6 weeks due to osteomyelitis and made a good recovery.

Background: There have been some reports on the use of intra-arterial tirofiban in ruptured intracranial aneurysms, but few studies have reported on the use of 24 h of intravenous tirofiban infusion in patients with subarachnoid hemorrhage., Objective: To present our experience with intravenous tirofiban infusion, in the form of a monotherapy as well as in addition to intra-arterial tirofiban, as a prophylactic, and as a rescue management for thrombus in patients who have undergone embolization with coils for ruptured intracranial aneurysms., Methods: Between December 2008 and January 2015, we retrospectively reviewed 249 ruptured intracranial aneurysms that were treated with coiling at our institutions. A total of 28 patients harboring 28 ruptured and 3 unruptured intracranial aneurysms underwent intravenous tirofiban infusion during or after coil embolization of an aneurysm. Intra-arterial infusion of tirofiban via a microcatheter was also performed in 26 patients., Results: Thromboembolic formation during the procedure was detected in 25 cases. Intra-arterial tirofiban dissolved the thromboembolus under angiographic control after 10 or more minutes in 19 (76%) of 25 patients. Two intracranial hemorrhagic complications (increase in the extent of hematoma) occurred during the follow-up period. Two cases of other complications occurred: hematuria and perioral bleeding., Conclusion: Intravenous tirofiban, as a monotherapy or in addition to intra-arterial tirofiban for thrombotic complications, seems to be useful as a treatment for acute aneurysm. However, alternatives to tirofiban should be considered if an associated hematoma is discovered before a patient receives a tirofiban infusion., (Copyright © 2017 by the Congress of Neurological Surgeons)

Background: Transvenous (TV) embolization is ideal for endovascular treatment of intracranial dural arteriovenous fistulas (DAVF). However, it is not always feasible because of various factors, and transarterial (TA) embolization could then be tried. We aimed to determine the incidence of distally enlarged feeding artery phenomenon and the major feeding artery in DAVF. If the TV approach is difficult and this phenomenon is observed, we could use this vessel for transarterial intravenous (TAIV) embolization as an endovascular treatment modality for DAVF., Methods: Forty-four patients with intracranial DAVF treated by the endovascular procedure between 2009 and 2016 were retrospectively reviewed. Their clinical records, angiography reports, and embolization procedure notes were studied, and their angiographies were chronologically classified into proliferative and restrictive types., Results: In 14 of 44 patients (32%), we observed the distally enlarged feeding artery phenomenon. The most common enlarged artery was the middle meningeal artery. The distally enlarged feeding artery group was predominantly the restrictive type, and the other group was proliferative in nature (P < 0.001). Of the 14 patients, 7 underwent TAIV embolization, and the other 7 underwent TV embolization., Conclusions: Distally enlarged feeding artery phenomenon was observed in 32% of patients with intracranial DAVF. This group was predominantly the restrictive type. We conclude that this phenomenon might help determine a patient's eligibility for TAIV embolization when TV embolization is difficult or impossible., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background and Purpose: Multiple hypointense vessels (MHV) on susceptibility-weighted imaging (SWI) is associated with an increased oxygen demand in acute cerebral ischemia. Occasionally, some patients exhibit extensive MHV on SWI despite of negative diffusion-weighted imaging (DWI), which is a phenomenon called total mismatch DWI-SWI. We analyzed the clinical characteristics and imaging findings in patients with the total DWI-SWI mismatch., Materials and Methods: We selected patients with total DWI-SWI mismatch who underwent MRI within 12hours from onset. To evaluate the degree of collateral flow, we graded vessels on post-contrast time-of-flight MR angiography as 3 groups. Perfusion lesion volume was measured using threshold of>6seconds of mean transit time on perfusion-weighted imaging., Results: Total DWI-SWI mismatch was found in 10 (2.7%) out of 370 patients. Four out of 10 patients were excluded due to lack of data on perfusion studies. Hence 6 patients were finally selected in the study. Two patients with internal carotid artery dissection were treated with emergent stenting, one patient with intravenous thrombolysis and mechanical thrombectomy, and two patients with drug-induced hypertension. All of the enrolled patients exhibited extensive MHV on SWI and good collateral flows. The mean perfusion lesion volume was 72.6±15.3ml (range 0-325.0ml). Clinical outcome was favorable in all of the patients (mRS at 3 months, 0)., Conclusions: Our results demonstrate that total mismatch of DWI-SWI is associated with good collateral flow and may be a predictor of good response to treatment in patients with acute cerebral ischemia., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Background/aims: To investigate the correlation between strabismus and the severity of white matter damage of immaturity (WMDI), based on MRI findings. Although strabismus is commonly associated with WMDI, its clinical features are not well established., Methods: This cross-sectional study involved 73 consecutive patients who visited the department of ophthalmology and were diagnosed with WMDI. The severity of WMDI was graded based on the MRI findings of the patients. All of the patients underwent complete ophthalmic examination, and strabismus was characterised in terms of direction, constancy, and angle of deviation. The prevalence and the characteristics of strabismus and their correlation with the grade of WMDI were investigated., Results: The perinatal characteristics, age at MRI, and the number of MRIs per child did not differ between different grades of WMDI. Refractive errors, found in 56 (76.7%) patients, did not differ between the grades of WMDI either. Strabismus was observed in 38 (52.1%) patients, and its prevalence increased with the grade of the disorder; 20 patients had exotropia and 18 had esotropia. Constant strabismus was found more frequently in patients with higher grade WMDI. However, the direction and angle of deviation did not differ depending on the grade of WMDI., Conclusions: The prevalence of strabismus increased with the severity of WMDI and was higher among patients with WMDI than among healthy individuals. The severity of WMDI might be related to the presence and constancy of strabismus., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Nanoprobes with multimodal functionality have attracted significant interest recently because of their potential applications in nanomedicine. This paper reports the successful development of lanthanide-doped Y₂O₃ nanoprobes for potential applications in optical and magnetic resonance (MR) imaging. The morphology, structural, and optical properties of these nanoprobes were characterized by transmission electron microscope (TEM), field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), and photoluminescence (PL). The cytotoxicity test showed that the prepared lanthanide-doped Y₂O₃ nanoprobes have good biocompatibility. The obvious contrast enhancement in the T₁-weighted MR images suggested that these nanoprobes can be used as a positive contrast agent in MRI. In addition, the clear fluorescence images of the L-929 cells incubated with the nanoprobes highlight their potential for optical imaging. Overall, these results suggest that prepared lanthanide-doped Y₂O₃ nanoprobes can be used for simultaneous optical and MR imaging.

MR findings of early infectious spondylodiscitis are non-specific and may be confused with those of other conditions. Therefore, it is important to recognize early MR signs of conditions, such as inappreciable cortical changes in endplates, confusing marrow signal intensities of vertebral bodies, and inflammatory changes in paraspinal soft tissues, and subligamentous and epidural spaces. In addition, appreciation of direct inoculation, such as in iatrogenic spondylodiscitis may be important, because the proportion of patients who have undergone recent spine surgery or a spinal procedure is increasing. In this review, the authors focus on the MR findings of early spondylodiscitis, atypical findings of iatrogenic infection, and the differentiation between spondylodiscitis and other disease entities mimicking infection.

Thyroid nodules are a very common problem. Since malignant thyroid nodules should be treated surgically, preoperative diagnosis of thyroid cancer is very crucial. Cytopathologic analysis of percutaneous fine-needle aspiration (FNA) specimens is the current gold standard for diagnosing thyroid nodules. However, this method has led to high rates of inconclusive results. Metabolomics has emerged as a useful tool in medical fields and shown great potential in diagnosing various cancers. Here, we evaluated the potential of nuclear magnetic resonance (NMR) analysis of percutaneous FNA specimens for preoperative diagnosis of thyroid cancer. We analyzed metabolome of FNA samples of papillary thyroid carcinoma (n = 35) and benign follicular nodule (n = 69) using a proton NMR spectrometer. The metabolomic profiles showed a considerable discrimination between benign and malignant nodules. Receiver operating characteristic (ROC) curve analysis indicated that seven metabolites could serve as discriminators (area under ROC curve value, 0.64-0.85). These findings demonstrated that NMR analysis of percutaneous FNA specimens of thyroid nodules can be potentially useful in the accurate and rapid preoperative diagnosis of thyroid cancer.

Background: Multi-detector computed tomography (MDCT) angiography is now used for the diagnosing patients with peripheral arterial disease. The dose of radiation is related to variable factors, such as tube current, tube voltage, and helical pitch., Purpose: To assess the diagnostic performance and radiation dose of lower extremity CT angiography (CTA) using a 128-slice dual source CT at 80 kVp and high pitch in patients with critical limb ischemia (CLI)., Material and Methods: Twenty-eight patients (mean, 64.1 years; range, 39-80 years) with CLI were enrolled in this retrospective study and underwent CTA using a 128-slice dual source CT at 80 kVp and high pitch and subsequent intra-arterial digital subtraction angiography (DSA), which was used as a reference standard for assessing diagnostic performance., Results: For arterial segments with significant disease (>50% stenosis), overall sensitivity, specificity, and accuracy of lower extremity CTA were 94.8% (95% CI, 91.7-98.0%), 91.5% (95% CI, 87.7-95.2%), and 93.1% (95% CI, 90.6-95.6%), respectively, and its positive and negative predictive values were 91.0% (95% CI, 87.1-95.0%), and 95.1% (95% CI, 92.1-98.1%), respectively. Mean radiation dose delivered to lower extremities was 266.6 mGy.cm., Conclusion: Lower extremity CTA using a 128-slice dual source CT at 80 kVp and high pitch was found to have good diagnostic performance for the assessment of patients with CLI using an extremely low radiation dose., (© The Foundation Acta Radiologica 2015.)

Purpose: We compared maximal diameters of ipsilateral (IMA) and contralateral (IMA) internal mammary arteries in patients with unilateral breast cancer and analyze the implications of enlargements of ipsilateral or contralateral IMAs in relation to histopathologic factors., Materials and Methods: Of 568 women who underwent breast magnetic resonance imaging (MRI) examinations from January 2009 to May 2012, 196 had unilateral, histologically proven breast cancer. In 156 women, maximal IMA diameters in the second intercostal space were measured by two blinded radiologists in left and right sides using nonenhanced axial T2-weighted turbo spin-echo sequence images., Results: In the 156 study patients, mean maximal diameter of ipsilateral IMAs (2.37 ± 0.60 mm) was significantly larger than that of contralateral IMAs (2.03 ± 0.58 mm) (p = 0.00). Ipsilateral IMA enlargement was present in 66.7 % of the patients (104 of 156). Furthermore, ipsilateral IMA enlargement was found to be significantly associated with human epidermal growth factor receptor-2 (HER-2) expression (p = 0.039)., Conclusions: Maximal IMA diameter was significantly greater in ipsilateral sides in breast cancer patients. Findings suggest ipsilateral IMA enlargement detected by MRI might be a useful additional predictor of HER-2 expression in unilateral breast cancer.

Objective: Stent-assisted coil embolization for the treatment of intracranial aneurysms has been used widely. This study aimed to investigate the effect of stent implantation in the nonatherosclerotic parent artery with cerebral aneurysms. The authors evaluated luminal changes and the related factors following stent-assisted coil embolization., Methods: This study included 97 patients harboring a total of 99 unruptured aneurysms of the distal internal carotid artery (ICA) who underwent single-stent implantation and more than 1 session of conventional angiography during follow-up (midterm follow-up only, n = 70; midterm and long-term follow-up, n = 29) between January 2009 and April 2014. The luminal narrowing point was measured using a local thickness map (ImageJ plug-in)., Results: Stent-assisted coil embolization caused dynamic luminal narrowing of approximately 82% of the parent artery diameter on average after 8 months, which was reversed to 91% after 25 months. In addition, luminal narrowing greater than 40% was noticed in 2 (7%) of the 29 patients who experienced spontaneous reversion without additional management during follow-up. Most luminal narrowing changes seen were diffuse., Conclusions: Luminal narrowing after aneurysm stent-assisted coil embolization is a dynamic process and appears to be a spontaneously reversible event. Routine management of luminal narrowing may not cause adverse events that require additional treatment.

Background: Embolization of intracranial aneurysms with the use of detachable coils has become the most widely used therapy for this condition. However, unexpected device failure can lead to critical complications., Objective: To describe an alternative detachment technique for various electrically detachable coils (eg, Target of Stryker Neurovascular, Presidio and Microphere of Codman Neurovascular, and MicroPlex and Hydrocoil of MicroVention Terumo) that can be used when standard troubleshooting techniques are not effective and the physician is not able to remove a coil., Methods: The alternative detachment method involved the restoration of the current pathway with the use of an alligator clip wire and the distal end of a new coil delivery wire of the same type. The detachment mechanism used in this method is the same as that normally used for each system., Results: We found that this alternative maneuver was both feasible and reproducible. Moreover, an electrically detachable coil was successfully detached with the use of this method, especially when detachment failure was the result of distal delivery wire and connector damage. No additional complications were noted., Conclusion: An alternative detachment technique involving the reconstruction of the electric circuit could be a safe method of rescue in the potentially risky situation caused by detachment failure during embolization of cerebral aneurysms with electrically detachable coils.

To retrospectively evaluate the image quality of CT angiography (CTA) reconstructed by model-based iterative reconstruction (MBIR) and to compare this with images obtained by filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR) in newborns and infants with congenital heart disease (CHD). Thirty-seven children (age 4.8 ± 3.7 months; weight 4.79 ± 0.47 kg) with suspected CHD underwent CTA on a 64detector MDCT without ECG gating (80 kVp, 40 mA using tube current modulation). Total dose length product was recorded in all patients. Images were reconstructed using FBP, ASIR, and MBIR. Objective image qualities (density, noise) were measured in the great vessels and heart chambers. The contrast-to-noise ratio (CNR) was calculated by measuring the density and noise of myocardial walls. Two radiologists evaluated images for subjective noise, diagnostic confidence, and sharpness at the level prior to the first branch of the main pulmonary artery. Images were compared with respect to reconstruction method, and reconstruction times were measured. Images from all patients were diagnostic, and the effective dose was 0.22 mSv. The objective image noise of MBIR was significantly lower than those of FBP and ASIR in the great vessels and heart chambers (P < 0.05); however, with respect to attenuations in the four chambers, ascending aorta, descending aorta, and pulmonary trunk, no statistically significant difference was observed among the three methods (P > 0.05). Mean CNR values were 8.73 for FBP, 14.54 for ASIR, and 22.95 for MBIR. In addition, the subjective image noise of MBIR was significantly lower than those of the others (P < 0.01). Furthermore, while FBP had the highest score for image sharpness, ASIR had the highest score for diagnostic confidence (P < 0.05), and mean reconstruction times were 5.1 ± 2.3 s for FBP and ASIR and 15.1 ± 2.4 min for MBIR. While CTA with MBIR in newborns and infants with CHD can reduce image noise and improve CNR more than other methods, it is more time-consuming than the other methods.

Background and Purpose: The usefulness of pharmacokinetic parameters for glioma grading has been reported based on the perfusion data from parts of entire-tumor volumes. However, the perfusion values may not reflect the entire-tumor characteristics. Our aim was to investigate the feasibility of glioma grading by using histogram analyses of pharmacokinetic parameters including the volume transfer constant, extravascular extracellular space volume per unit volume of tissue, and blood plasma volume per unit volume of tissue from T1-weighted dynamic contrast-enhanced perfusion MR imaging., Materials and Methods: Twenty-eight patients (14 men, 14 women; mean age, 49.75 years; age range, 25-72 years) with histopathologically confirmed gliomas (World Health Organization grade II, n = 7; grade III, n = 8; grade IV, n = 13) were examined before surgery or biopsy with conventional MR imaging and T1-weighted dynamic contrast-enhanced perfusion MR imaging at 3T. Volume transfer constant, extravascular extracellular space volume per unit volume of tissue, and blood plasma volume per unit volume of tissue were calculated from the entire-tumor volume. Histogram analyses from these parameters were correlated with glioma grades. The parameters with the best percentile from cumulative histograms were identified by analysis of the area under the curve of the receiver operating characteristic analysis and were compared by using multivariable stepwise logistic regression analysis for distinguishing high- from low-grade gliomas., Results: All parametric values increased with increasing glioma grade. There were significant differences among the 3 grades in all parameters (P < .01). For the differentiation of high- and low-grade gliomas, the highest area under the curve values were found at the 98th percentile of the volume transfer constant (area under the curve, 0.912; cutoff value, 0.277), the 90th percentile of extravascular extracellular space volume per unit volume of tissue (area under the curve, 0.939; cutoff value, 19.70), and the 84th percentile of blood plasma volume per unit volume of tissue (area under the curve, 0.769; cutoff value, 11.71). The 98th percentile volume transfer constant value was the only variable that could be used to independently differentiate high- and low-grade gliomas in multivariable stepwise logistic regression analysis., Conclusions: Histogram analysis of pharmacokinetic parameters from whole-tumor volume data can be a useful method for glioma grading. The 98th percentile value of the volume transfer constant was the most significant measure., (© 2014 by American Journal of Neuroradiology.)

Purpose: To explore the role of histogram analysis of apparent diffusion coefficient (ADC) maps obtained at standard- and high-b-value (1000 and 3000 sec/mm(2), respectively) diffusion-weighted (DW) imaging in the differentiation of true progression from pseudoprogression in glioblastoma treated with radiation therapy and concomitant temozolomide., Materials and Methods: This retrospective study was approved by the institutional review board of Seoul National University Hospital, and informed consent requirement was waived. Thirty patients with histopathologically proved glioblastoma who had undergone concurrent chemotherapy and radiation therapy (CCRT) with temozolomide underwent diffusion-weighted MR imaging with b values of 1000 and 3000 sec/mm(2), and corresponding ADC maps were calculated from entire newly developed or enlarged enhancing lesions after completion of CCRT. Histogram parameters of each ADC map between true progression (n = 15) and pseudoprogression (n = 15) groups were compared by using the unpaired Student t test. Receiver operating characteristic analysis was used to determine the best cutoff values for predictors in the differentiation of true progression from pseudoprogression. Results were validated in an independent test set of nine patients by using the best cutoff value to predict differentiation of true progression from pseudoprogression. The accuracy of the selected best cutoff value in the independent test set was then calculated., Results: In terms of cumulative histograms, the fifth percentile of both ADC at b value of 1000 sec/mm(2) (ADC1000) and the ADC at b value of 3000 sec/mm(2) (ADC3000) were significantly lower in the true progression group than in the pseudoprogression group (P = .049 and P < .001, respectively). In contrast, neither the mean ADC1000 nor the mean ADC3000 was significantly different between the two groups. The diagnostic values of the parameters derived from ADC1000 and ADC3000 were compared, and a significant difference (0.224, P = .016) was found between the area under the receiver operating characteristic curve of the fifth percentile for ADC1000 and that for ADC3000. The accuracies were 66.7% (six of nine patients) and 88.9% (eight of nine patients) based on the fifth percentile of both ADC1000 and ADC3000 in the independent test set, respectively., Conclusion: The fifth percentile of the cumulative ADC histogram obtained at a high b value was the most promising parameter in the differentiation of true progression from pseudoprogression of the newly developed or enlarged enhancing lesions after CCRT with temozolomide for glioblastoma treatment. Online supplemental material is available for this article., (© RSNA, 2013.)

Purpose: To evaluate the usefulness of dynamic susceptibility contrast (DSC) enhanced perfusion MR imaging in predicting major genetic alterations in glioblastomas., Materials and Methods: Twenty-five patients (M:F = 13∶12, mean age: 52.1±15.2 years) with pathologically proven glioblastoma who underwent DSC MR imaging before surgery were included. On DSC MR imaging, the normalized relative tumor blood volume (nTBV) of the enhancing solid portion of each tumor was calculated by using dedicated software (Nordic TumorEX, NordicNeuroLab, Bergen, Norway) that enabled semi-automatic segmentation for each tumor. Five major glioblastoma genetic alterations (epidermal growth factor receptor (EGFR), phosphatase and tensin homologue (PTEN), Ki-67, O6-methylguanine-DNA methyltransferase (MGMT) and p53) were confirmed by immunohistochemistry and analyzed for correlation with the nTBV of each tumor. Statistical analysis was performed using the unpaired Student t test, ROC (receiver operating characteristic) curve analysis and Pearson correlation analysis., Results: The nTBVs of the MGMT methylation-negative group (mean 9.5±7.5) were significantly higher than those of the MGMT methylation-positive group (mean 5.4±1.8) (p = .046). In the analysis of EGFR expression-positive group, the nTBVs of the subgroup with loss of PTEN gene expression (mean: 10.3±8.1) were also significantly higher than those of the subgroup without loss of PTEN gene expression (mean: 5.6±2.3) (p = .046). Ki-67 labeling index indicated significant positive correlation with the nTBV of the tumor (p = .01)., Conclusion: We found that glioblastomas with aggressive genetic alterations tended to have a high nTBV in the present study. Thus, we believe that DSC-enhanced perfusion MR imaging could be helpful in predicting genetic alterations that are crucial in predicting the prognosis of and selecting tailored treatment for glioblastoma patients.

Purpose: To compare the reproducibilities of manual and semiautomatic segmentation method for the measurement of normalized cerebral blood volume (nCBV) using dynamic susceptibility contrast-enhanced (DSC) perfusion MR imaging in glioblastomas., Materials and Methods: Twenty-two patients (11 male, 11 female; 27 tumors) with histologically confirmed glioblastoma (WHO grade IV) were examined with conventional MR imaging and DSC imaging at 3T before surgery or biopsy. Then nCBV (means and standard deviations) in each mass was measured using two DSC MR perfusion analysis methods including manual and semiautomatic segmentation method, in which contrast-enhanced (CE)-T1WI and T2WI were used as structural imaging. Intraobserver and interobserver reproducibility were assessed according to each perfusion analysis method or each structural imaging. Interclass correlation coefficient (ICC), Bland-Altman plot, and coefficient of variation (CV) were used to evaluate reproducibility., Results: Intraobserver reproducibilities on CE-T1WI and T2WI were ICC of 0.74-0.89 and CV of 20.39-36.83% in manual segmentation method, and ICC of 0.95-0.99 and CV of 8.53-16.19% in semiautomatic segmentation method, repectively. Interobserver reproducibilites on CE-T1WI and T2WI were ICC of 0.86-0.94 and CV of 19.67-35.15% in manual segmentation method, and ICC of 0.74-1.0 and CV of 5.48-49.38% in semiautomatic segmentation method, respectively. Bland-Altman plots showed a good correlation with ICC or CV in each method. The semiautomatic segmentation method showed higher intraobserver and interobserver reproducibilities at CE-T1WI-based study than other methods., Conclusion: The best reproducibility was found using the semiautomatic segmentation method based on CE-T1WI for structural imaging in the measurement of the nCBV of glioblastomas.

Background: Glioma grading assumes significant importance in that low- and high-grade gliomas display different prognoses and are treated with dissimilar therapeutic strategies. The objective of our study was to retrospectively assess the usefulness of a cumulative normalized cerebral blood volume (nCBV) histogram for glioma grading based on 3 T MRI., Methods: From February 2010 to April 2012, 63 patients with astrocytic tumors underwent 3 T MRI with dynamic susceptibility contrast perfusion-weighted imaging. Regions of interest containing the entire tumor volume were drawn on every section of the co-registered relative CBV (rCBV) maps and T2-weighted images. The percentile values from the cumulative nCBV histograms and the other histogram parameters were correlated with tumor grades. Cochran's Q test and the McNemar test were used to compare the diagnostic accuracies of the histogram parameters after the receiver operating characteristic curve analysis. Using the parameter offering the highest diagnostic accuracy, a validation process was performed with an independent test set of nine patients., Results: The 99th percentile of the cumulative nCBV histogram (nCBV C99), mean and peak height differed significantly between low- and high-grade gliomas (P = <0.001, 0.014 and <0.001, respectively) and between grade III and IV gliomas (P = <0.001, 0.001 and <0.001, respectively). The diagnostic accuracy of nCBV C99 was significantly higher than that of the mean nCBV (P = 0.016) in distinguishing high- from low-grade gliomas and was comparable to that of the peak height (P = 1.000). Validation using the two cutoff values of nCBV C99 achieved a diagnostic accuracy of 66.7% (6/9) for the separation of all three glioma grades., Conclusion: Cumulative histogram analysis of nCBV using 3 T MRI can be a useful method for preoperative glioma grading. The nCBV C99 value is helpful in distinguishing high- from low-grade gliomas and grade IV from III gliomas.

In this study, the effects of sitagliptin analogue (SITA) or pioglitazone (PIO) treatment on glucose homeostasis and Β-cell dynamics in animal models of type 2 diabetes--Akita and db/db mice were evaluated. After 4-6 weeks of treatment, both SITA and PIO were shown to lower non-fasting glucose levels and reduced glycemic excursion in the intraperitoneal glucose tolerance test. In addition, both drugs preserved normal islet structure and the proportion of Β-cells in the islets. Compared to the controls, SITA treatment induced a higher Β-cell proliferation rate in Akita mice and a lower rate of apoptosis in db/db mice, whereas PIO treatment induced a lower rate of apoptosis in db/db mice and reduced proliferation rates in Akita mice. In conclusion, both SITA and PIO appear to exert some beneficial effects on the islet structure in addition to glycemic control via different mechanisms that involve Β-cell dynamics in Akita and db/db mice. [BMB reports 2011; 44(11): 713-718].

Objective: This study was designed to identify and describe thin-section computed tomographic (CT) findings of primary multidrug-resistant tuberculosis (MDR TB) as compared with the findings for drug-sensitive TB., Methods: Between October 2002 and December 2007, thin-section chest CT findings of 39 patients with primary MDR TB and 39 patients with drug-sensitive TB were retrospectively reviewed. The frequency and patterns of lung lesions (including centrilobular nodules, large nodules, consolidation, cavity, fibrotic bands, bronchiectasis, calcification, pleural effusion, lymphadenopathy, number of lobes affected by parenchymal lesions, and laterality) were compared. Statistical comparisons were performed with the use of the chi2 and the Mann-Whitney U tests for univariate analysis, and a stepwise logistic regression method was used for multivariate analysis., Results: Based on univariate analysis, bilateral involvement (P < 0.001), segmental or lobar consolidation (P < 0.001), and cavities (P < 0.001) were more frequently seen in primary MDR TB patients. A stepwise logistic regression analysis demonstrated that bilateral involvement of parenchymal lesions (odds ratio, 4.7; 95% confidence interval, 1.4-15.6; P = 0.012) and multiple cavities (odds ratio, 1.7; 95% confidence interval, 1.2-2.5; P = 0.004) were significant CT findings associated with primary MDR TB., Conclusions: The presence of primary MDR TB as detected on a CT scan may help the use of appropriate therapy for infected patients before obtaining a definite diagnosis based on bacteriology.

Vibrio vulnificus causes acute cell death and a fatal septicaemia. In this study, we show that contact with host cells is a prerequisite to the acute cytotoxicity. We screened transposon mutants defective in the contact-dependent cytotoxicity. Two mutants had insertions within two open reading frames in a putative RTX toxin operon, the rtxA1 or rtxD encoding an RTX toxin (4701 amino acids) or an ABC type transporter (467 amino acids). An rtxA1 mutation resulted in a cytotoxicity defect, which was fully restored by in trans complementation. The expression of RtxA1 toxin increased after host cell contact in a time-dependent manner. The RtxA1 toxin induced cytoskeletal rearrangements and plasma membrane blebs, which culminated in a necrotic cell death. RtxA1 colocalized with actin and caused actin aggregation coinciding with a significant decrease in the F/G actin ratio. The RtxA1 toxin caused haemolysis through pore formation (radius 1.63 nm). The rtxA1 deletion mutant was defective in invading the blood stream from ligated ileal loops of CD1 mice. The rtxA1 null mutation resulted in over 100-fold increase in both intragastric and intraperitoneal LD(50)s against mice. Overall, these results show that the RtxA1 toxin is a multifunctional cytotoxin and plays an essential role in the pathogenesis of V. vulnificus infections.