Endovascular Treatment of Traumatic Vascular Injuries in the Head and Neck Region.

Background and Objectives: Traumatic vascular injuries of the head and neck pose significant treatment challenges due to the complex anatomy, diverse clinical presentation, and mostly emergent nature. Endovascular treatment increasingly complements traditional surgical approaches. This study aimed to report our 10-year experience in treating traumatic vascular injuries of the head and neck with endovascular therapy and to determine the effectiveness of endovascular treatment. Materials and Methods: A retrospective analysis of 21 patients treated for head and neck vascular injuries between May 2011 and April 2021 was performed. Patients' medical histories, clinical presentations, imaging findings, treatment materials, and clinical outcomes were reviewed. Treatments included stenting, coil embolization, and other endovascular techniques focused on hemostasis and preservation of the parent vessel. Results: The most common injuries involved the internal maxillary artery branches (n = 11), followed by the common or internal carotid artery (n = 6), vertebral artery (n = 3), and others. Endovascular treatment achieved successful hemostasis in all but one case. In five of six carotid artery injuries and two of three vertebral artery injuries, we achieved successful hemostasis while preserving the parent vessel using covered and bare stents, respectively. Conclusions: Endovascular therapy might be a useful treatment modality for traumatic vascular injuries in the head and neck region, offering efficacy, safety, and a minimally invasive approach.

Lobar emphysema ratio of more than 1% in the lobe with lung cancer as poor predictor for recurrence and overall survival in patients with stage I non-small cell lung cancer.

BACKGROUND: The purpose of this study was to examine the relationship between the lobar emphysema ratio (LER) and tumor recurrence and survival in patients with stage I non-small cell lung cancer (NSCLC). METHODS: We enrolled 258 patients with surgically proven stage I NSCLC. These patients underwent noncontrast chest CT, and pulmonary lobe segmentation and lobar emphysema quantification were performed using commercially available software. We assessed the LER in the lobe with lung cancer. We divided the patients into two groups according to the LER, and the cut-off value was 1. Furthermore, we analyzed the disease-free survival of high LER and other clinical factors after surgical resection. RESULTS: The 258 patients were divided into two groups: low LER (n = 195) and high LER (n = 63). The right upper lobe was the most frequent location in lung cancer and the most severe location in emphysema. In the Kaplan‒Meier curve, high LER showed a significantly lower disease-free survival (8.21 ± 0.27 years vs 6.53 ± 0.60 years, p = 0.005) and overall survival (9.56 ± 0.15 years vs. 8.51 ± 0.49 years, p = 0.011) than low LER. Stage Ib (2.812 [1.661-4.762], p<0.001) and high LER (2.062 [1.191-3.571], p = 0.010) were poor predictors for disease-free survival in multivariate Cox regression analysis. Stage Ib (4.729 [1.674-13.356], p = 0.003) and high LER (3.346 [1.208-9.269], p = 0.020) were significant predictors for overall survival in multivariate Cox regression analysis. CONCLUSION: A LER of more than 1% in the lobe with lung cancer is a poor predictor for cancer recurrence and overall survival in patients with stage I NSCLC.

Mucoepidermoid carcinoma of the breast: A case report and literature review focused on radiological findings.

RATIONALE: Mucoepidermoid carcinoma (MEC) of the breast is a rare entity, with an estimated incidence of only 0.2% to 0.3% of all primary breast tumors. The radiological features of breast MEC have scarcely been investigated mainly because of its rarity. In this article, we present a case of breast MEC diagnosed at our hospital and review the literature, focusing on radiological findings and radiologic-pathologic correlations that could improve clinical management of this entity. To the best of our knowledge, our study is the first review of the literature that focuses on the radiological features of breast MEC. PATIENT CONCERNS: A 47-year-old premenopausal woman presented with a painless palpable mass in the right breast. DIAGNOSIS: Mammography and ultrasonography revealed a mass with suspicious malignant features, which was categorized as Breast Imaging Reporting and Data System category 4c. A 14-gauge core-needle biopsy revealed an intermediate-grade MEC of the breast. The patient underwent breast magnetic resonance imaging and chest computed tomography for preoperative evaluation. Postoperative histopathological examination confirmed a diagnosis of intermediate-grade MEC. The clinical staging was T2N0M0. INTERVENTIONS: The patient underwent breast-conserving surgery, adjuvant chemotherapy, radiotherapy, and hormonal therapy. OUTCOMES: No evidence of recurrence has been reported over 37 months. LESSONS: The imaging characteristics of breast MEC were variable, and there were no specific radiological features for diagnosis. The presence of cystic components on radiological imaging is likely to be an indicator of a low-grade tumor and better prognosis, although the number of reported cases is limited.

Quantification of liver extracellular volume using dual-energy CT for ruling out high-risk varices in cirrhosis.

PURPOSE: To determine the performance of quantification of liver extracellular volume fraction (fECV) using dual-energy CT (DECT) compared with CT imaging for ruling out high-riskesophageal varices(HRV) in cirrhotic patients. METHODS: We retrospectively analyzed 229 cirrhotic patients (training [n = 159] and internal validation cohorts [n = 70]) who underwent dual-source DECT, serum marker assessment, and esophagogastroduodenoscopy (EGD) from 2017 to 2020. The fECV score was measured using iodine maps from 3-minute delayed, equilibrium-phase images at 100/140 Sn kVp. The association of CT parameters and serum markers with HRV was investigated. Criteria combining the fECV score (≤ 25.1%) or CT imaging with platelet count (> 150,000/mm3) were created and compared to rule out HRV. RESULTS: In the training cohort, the fECV score (odds ratio (OR), 1.20; 95% confidence interval (CI), 1.09, 1.32) and CT imaging (OR, 28.21; 95% CI, 9.31, 85.93) were independent predictors of HRV, along with platelet count (OR, 0.85 and 0.78). Criteria combining the fECV score with platelet count showed significantly better performance than those combining CT imaging with platelet count in ruling out HRV (p < 0.001). Applying the criteria could have safely avoided an additional 10.7% and 8.6% of EGDs in the training and validation cohorts, respectively, achieving a final value of 36.5% and 35.7% spared EGDs (0 HRV missed) compared to CT imaging with platelet count. CONCLUSIONS: The combined DECT-based fECV score with platelet count is useful for ruling out HRV and can safely avoid more EGDs than CT imaging with platelet count.

Percutaneous removal of common bile duct stones using a modified balloon technique.

ABSTRACT: To evaluate the effectiveness of percutaneous removal of common bile duct (CBD) stones using a modified balloon technique (balloon catheter sphincteroplasty and expulsion of the stones using half-captured balloons within the sheath) in patients difficult to treat with endoscopy.Fifty patients underwent a modified balloon technique (balloon group), and 53 patients underwent CBD stone removal by the basket method (stone basket group) between 2016 and 2019. We compared the balloon and stone basket groups to evaluate the effectiveness of the modified balloon technique. Outcome variables such as demographics, technical success rates, procedural details, and complications were analyzed. Statistical analysis was performed using Student t test, Fisher exact test, or the χ2 test.The technical success rate in the balloon group was 66% (33/50) in 1 session, 32% (16/50) in 2 sessions, and 2% (1/50) in 3 sessions. That of the stone basket group was 45% (24/53) in 1 session, 38% (20/53) in 2 sessions, and 17% (9/53) in 3 sessions.The total procedure time was significantly shorter in the balloon group (29.5 ±â€Š15.1 minutes) than in the stone basket group (41.7 ±â€Š20.2 minutes) (P < .01), whereas the number of stones was higher in the balloon group than in the stone basket group (P = .03). Maximal stone size, balloon size, pancreatitis, and hospitalization stay did not show statistical differences between the 2 groups. Most complications (9 patients, balloon group; 8 patients, stone basket group) were mild and transient. Major complications occurred in one patient in the stone basket group, who experienced hemobilia due to arterial injury caused by percutaneous transhepatic biliary drainage, which was treated by endovascular embolization without mortality.The modified balloon technique is an effective and safe treatment method for CBD stone removal in patients presenting difficulties in the endoscopic approach.

T2 mapping in gadoxetic acid-enhanced MRI: utility for predicting decompensation and death in cirrhosis.

OBJECTIVES: To determine whether T2 mapping in liver MRI can predict decompensation and death in cirrhotic patients. METHODS: This retrospective study included 292 cirrhotic patients who underwent gadoxetic acid-enhanced MRI, including T1 and T2 mapping at 10-min hepatobiliary phase by using the Look-Locker and radial turbo spin-echo sequences, respectively. T1 and T2 values of the liver and spleen were measured. The association of MR parameters and serum markers with decompensation and death was investigated. Risk models combining T2Liver, serum albumin level, and Model for End-Stage Liver Disease (MELD) score were created for predicting decompensation (T2Liver, < 49.3 versus ≥ 49.3 ms) and death (< 57.4 versus ≥ 57.4 ms). RESULTS: In patients with compensated cirrhosis at baseline and in the full patient cohort, 9.6% (19 of 197) and 5.1% (15 of 292) developed decompensation and died during the mean follow-up periods of 18.7 and 19.2 months, respectively. A prolonged T2Liver (hazard ratio (HR), 2.59; 95% confidence interval (CI), 1.26, 5.31) was independently predictive of decompensation along with the serum albumin level (HR, 0.28; 95% CI, 0.12, 0.68) and MELD score (HR, 1.34; 95% CI, 1.08, 1.66). T2Liver (HR, 2.61; 95% CI, 1.19, 5.72) and serum albumin level (HR, 0.46; 95% CI, 0.19, 1.14) were independent predictors of death. The mean times to decompensation (12.9 versus 29.2 months) and death (16.5 versus 29.6 months) were significantly different between the high- and low-risk groups (p < 0.001). CONCLUSION: T2Liver from T2 mapping can predict decompensation and death in patients with cirrhosis. KEY POINTS: • Liver T2 values from the radial turbo spin-echo (TSE) T2 mapping sequence with tiered echo sharing and pseudo golden-angle (pGA) reordering were significantly higher in decompensated cirrhosis than compensated cirrhosis. • Liver T2 values from the radial TSE T2 mapping sequence with tiered echo sharing and pGA reordering can predict decompensation and death in patients with cirrhosis. • T2 mapping is recommended as part of liver MRI examinations for cirrhotic patients because it can provide a noninvasive prognostic marker for the development of decompensation and death.

Malignancy Risk Stratification of Thyroid Nodules with Macrocalcification and Rim Calcification Based on Ultrasound Patterns.

OBJECTIVE: To determine the association of macrocalcification and rim calcification with malignancy and to stratify the malignancy risk of thyroid nodules with macrocalcification and rim calcification based on ultrasound (US) patterns. MATERIALS AND METHODS: The study included a total of 3603 consecutive nodules (≥ 1 cm) with final diagnoses. The associations of macrocalcification and rim calcification with malignancy and malignancy risk of the nodules were assessed overall and in subgroups based on the US patterns of the nodules. The malignancy risk of the thyroid nodules was categorized as high (> 50%), intermediate (upper-intermediate: > 30%, ≤ 50%; lower-intermediate: > 10%, ≤ 30%), and low (≤ 10%). RESULTS: Macrocalcification was independently associated with malignancy in all nodules and solid hypoechoic (SH) nodules (p < 0.001). Rim calcification was not associated with malignancy in all nodules (p = 0.802); however, it was independently associated with malignancy in partially cystic or isoechoic and hyperechoic (PCIH) nodules (p = 0.010). The malignancy risks of nodules with macrocalcification were classified as upper-intermediate and high in SH nodules, and as low and lower-intermediate in PCIH nodules based on suspicious US features. The malignancy risks of nodules with rim calcification were stratified as low and lower-intermediate based on suspicious US features. CONCLUSION: Macrocalcification increased the malignancy risk in all and SH nodules with or without suspicious US features, with low to high malignancy risks depending on the US patterns. Rim calcification increased the malignancy risk in PCIH nodules, with low and lower-intermediate malignancy risks based on suspicious US features. However, the role of rim calcification in risk stratification of thyroid nodules remains uncertain.

Low pectoralis muscle index, cavitary nodule or mass and segmental to lobar consolidation as predictors of primary multidrug-resistant tuberculosis: A comparison with primary drug sensitive tuberculosis.

BACKGROUND: The loss of muscle mass in primary multidrug-resistant tuberculosis (MDR-TB) has not been examined in previous studies. This study aimed to investigate that low pectoralis muscle index and characteristic CT features can help differentiate patients with primary MDR-TB from those with drug-sensitive tuberculosis (DS-TB). MATERIAL AND METHODS: From 2010 to 2016, we retrospectively enrolled 90 patients with primary MDR-TB and 90 age- and sex-matched patients with primary DS-TB. The pectoralis muscle mass was quantitatively measured on axial CT images using density histogram analysis. The pectoralis muscle index (PMI) was defined as the pectoralis muscle mass divided by body mass index. We compared the PMI and characteristic CT features of pulmonary tuberculosis between the two groups. RESULTS: Low PMI, segmental to lobar consolidation, cavity in consolidation, cavitary nodule or mass, and bilateral involvement were more frequently observed in patients with MDR-TB than in those with DS-TB. In stepwise multivariate logistic regression analysis, low PMI (odds ratio, 2.776; 95% confidence interval, 1.450-5.314; p = 0.002), segmental or lobar consolidation (odds ratio, 3.123; 95% confidence interval, 1.629-5.987; p = 0.001), and cavitary nodule or mass (odds ratio, 2.790; 95% confidence interval, 1.348-5.176; p = 0.002) were significant factors for MDR-TB. CONCLUSION: Low pectoralis muscle index, segmental to lobar consolidation and cavitary nodule or mass can help differentiate primary MDR-TB from DS-TB.

Quantification of liver extracellular volume using dual-energy CT: utility for prediction of liver-related events in cirrhosis.

OBJECTIVES: To determine whether quantification of liver extracellular volume fraction (fECV) using dual-energy CT (DECT) allows prediction of liver-related events (LREs) in cirrhotic patients. METHODS: This retrospective study included 305 cirrhotic patients who underwent dual-source DECT imaging and had serum markers analyzed within 2 weeks of initial CT imaging. The fECV score was measured using an iodine map of equilibrium-phase images obtained 3 min after contrast injection at 100/140 Sn kVp. The association of the fECV score and serum markers with LREs was investigated. A risk model combining the fECV score (< 27 versus ≥ 27%) and serum albumin level (< 4 versus ≥ 4 g/dL) was constructed for LRE prediction. RESULTS: An increased fECV score (odds ratio, 1.27; 95% confidence interval (CI), 1.15, 1.40) was independently associated with decompensated cirrhosis at baseline (n = 85) along with the Model for End-Stage Liver Disease score (odds ratio, 1.32; 95% CI, 1.07, 1.63). Among patients with compensated cirrhosis, 10.5% (23 of 220) experienced LREs during the median follow-up period of 2.0 years (decompensation, n = 14; hepatocellular carcinoma, n = 9). The fECV score (hazard ratio, 1.40; 95% CI, 1.22, 1.62) and serum albumin level (hazard ratio, 0.26; 95% CI, 0.09, 0.73) were independent predictors of LRE. The mean times to LRE among the high (16.5 months, n = 18)-, intermediate (25.6 months, n = 44)-, and low (30.5 months, n = 158)-risk groups were significantly different (p < 0.001). CONCLUSIONS: The fECV score derived from DECT allows prediction of LREs in cirrhotic patients. KEY POINTS: • The extracellular volume fraction (fECV) score derived from the iodine map of dual-energy CT (DECT) was independently associated with the presence of hepatic decompensation. • The fECV score derived from the iodine map of DECT can predict liver-related events (LREs) in patients with cirrhosis. • Equilibrium-phase scanning in dual-energy mode is recommended as part of liver CT in cirrhotic patients because it can provide a prognostic indicator for LRE development.

A rare case of thyroglossal duct cyst extending to the sublingual space: A case report.

RATIONALE: Thyroglossal duct cyst (TGDC) is the most common congenital anomaly of midline neck masses. A thyroglossal duct cyst is especially difficult to diagnose and is treated differently when it appears in the sublingual area. Here, we report a rare case of TGDC extending to the sublingual space. PATIENT CONCERNS: A 42-year-old female presented with a history of neck swelling in the submental region. DIAGNOSIS: The final pathologic diagnosis was a TGDC. INTERVENTIONS: Sistrunk operation was performed. OUTCOMES: Recurrence of the disease has not been seen for the past year. LESSION: Clinical awareness of the thyroglossal duct cyst in the sublingual area or on the oral floor area is important for an accurate diagnosis and the appropriated management.

Combined treatment (image-guided thrombectomy and endovascular therapy with open femoral access) for acute lower limb ischemia: Clinical efficacy and outcomes.

OBJECTIVES: To evaluate the effectiveness and safety of combined treatment (image guided thrombectomy and endovascular therapy with open femoral access) for acute lower limb ischemia. METHODS: From 2009 to 2017, 52 patients (44 men, eight women, mean 67.2 years) underwent combined treatment for acute thrombotic occlusion of lower extremity arteries. The patients presented with acute limb ischemia and we selectively perform combined treatment in the cases with challenging clinical considerations (e.g. various spectrum of thrombus, underlying atherosclerotic lesions). Combined treatment included cutdown of common femoral artery, thrombectomy using a Fogarty balloon catheter, balloon angioplasty, stenting, and catheter-introduced thrombus fragmentation and aspiration. Patients' medical records were retrospectively reviewed and follow-up data were collected. The technical and clinical success rates and limb salvage were assessed. The Kaplan-Meier method was used to analyze primary patency rates and overall survival rates. Univariate analyses were performed to determine the factors related to clinical outcomes. RESULTS: Technical and clinical success rate was 90.4% and 80.8%, respectively. The mean follow-up duration was 26.5 ± 25.8 months. Primary patency was 91.4%, 86.1%, and 74.6% at six months, 1-, and 2-year, respectively. Limb salvage without amputation was 88.5% (46/52). The overall survival rates at six months, 1-, and 3-year were 82.6%, 80.2, and 56.9%, respectively. The 30-day mortality was 5.8% (3/52). Univariate analysis showed that percutaneous transluminal angioplasty (PTA) type (balloon versus stent) was related to clinical failure. CONCLUSIONS: Combined treatment can be effective and safe for ALI patients even under challenging clinical conditions.

Adverse effect of smoking on cross-sectional area of small pulmonary vessel and arterial stiffness in healthy smokers without COPD.

INTRODUCTION: Because it induces systemic inflammation, smoking is a risk factor of atherosclerosis and pulmonary hypertension. The brachial-ankle pulse wave velocity (baPWV) and cross-sectional area (CSA) of small pulmonary vessels can be useful markers to assess early changes of arterial stiffness and pulmonary vascular alteration in smokers. OBJECTIVES: This study aimed to explore association between the CSA of small pulmonary vessel and arterial stiffness in healthy male smokers. METHODS: We enrolled 90 male non-smokers and 90 male smokers (age: 51.5 ± 9.7 years and 52.1 ± 7.9 years, respectively). All subjects underwent chest computed tomography (CT), pulmonary function test and baPWV measurement. We evaluated the total CSAs less than 5 mm2 using ImageJ software and divided by the total lung area (%CSA<5). We compared the association between baPWV and %CSA<5 in two groups as well as correlations among the amount of smoking, baPWV and %CSA<5. Multiple linear regression analysis using %CSA<5 as the dependent variable was also performed. RESULTS: The mean baPWV and mean %CSA<5 were significantly different between the smokers and non-smokers. The pack-years was significantly correlated with %CSA<5 (r = -0.631, P < 0.001) and baPWV (r = 0.534, P < 0.001) in smokers. In multiple linear regression analysis, age, pack-years, FEV1 /FVC and baPWV were associated with %CSA<5, regardless of body mass index, blood pressure and heart rate. CONCLUSIONS: There is a dose-response relationship between cigarette smoking and the CSA of small pulmonary vessels and arterial stiffness, respectively. Arterial stiffness, age, pack-years and mild airflow impairment are independent predictors of small pulmonary vascular destruction in smokers.

Crossed cerebellar hyperperfusion in patients with seizure-related cerebral cortical lesions: an evaluation with arterial spin labelling perfusion MR imaging.

PURPOSE: Crossed cerebellar (CC) diaschisis refers to a decrease in cerebellar perfusion in the presence of contralateral supratentorial lesions. Most of the previous studies have examined stroke patients. In contrast to strokes, seizure-related cerebral cortical lesions (SCCLs) usually show hyperperfusion, and therefore, cerebellar perfusion patterns are expected to be different from those of strokes. With arterial spin labelling (ASL), we evaluated the cerebellar perfusion status in patients with SCCLs. MATERIALS AND METHODS: Using a search of the recent database over the last 31 months, 26 patients were enrolled in this study. The inclusion criteria were as follows: (1) a history of seizures, (2) MR examination taken within 24 h from the last seizure, (3) the presence of SCCLs on T2/FLAIR or DWI, (4) hyperperfusion in the corresponding areas of SCCLs on ASL, and (5) no structural abnormality in the cerebellum. The perfusion status in the contralateral cerebellum was evaluated and categorized as hyper-, iso- and hypoperfusion. The asymmetric index (AI) of cerebellar perfusion was calculated by ROI measurement of the signal intensity on ASL. RESULTS: The mean time between the last seizure and MR examinations was 5 h 30 min. CC hyperperfusion was observed in 17 patients (65.4%), hypoperfusion in 7 (26.9%) and isoperfusion in 2 (7.7%). Regarding the location of SCCLs, CC hyperperfusion was more frequent (71.4 vs. 58.3%), and the mean AI was higher (42.0 vs. 11.5) when the lesion involved the frontal lobe. CONCLUSIONS: In patients with SCCLs, CC hyperperfusion occurred more often than hypo- and isoperfusion, especially when the lesions involved the frontal lobe.

FSE T2-weighted two-point Dixon technique for fat suppression in the lumbar spine: comparison with SPAIR technique.

PURPOSE: Fat suppression magnetic resonance imaging (MRI) technique has been used to improve the diagnostic confidence in lumbar spine diseases. We aimed to compare T2-weighted water-fat separation technique (T2 Dixon) with spectral attenuated inversion recovery (SPAIR) image for fat suppression. METHODS: Lumbar spine MRI examinations were performed in 79 patients by using a 3.0 T machine. We compared T2 Dixon water-only image and SPAIR image for the evaluation of fat suppression quality and lesion conspicuity. For qualitative evaluation, two radiologists scored the images from Dixon and SPAIR for fat suppression uniformity and lesion conspicuity. Quantitative assessment was also performed for 39 lesions in 26 patients who had lesions in their spine bodies. Contrast ratio (CR) and contrast-to-noise ratio (CNR) were calculated by signal intensity measurement of the lesions, adjacent bodies, and background noise. The Wilcoxon's signed-rank test and paired sample t-test were used to assess the statistical significance of qualitative and quantitative data, respectively. RESULTS: For qualitative assessment, T2 Dixon water-only image showed higher mean scores for fat suppression quality and lesion conspicuity than SPAIR (2.99±0.11 vs. 2.18±0.38 and 2.84±0.37 vs. 2.28±0.51, respectively). For quantitative measurement, the CR and CNR values of the lesions were higher on T2 Dixon than on SPAIR. Both qualitative and quantitative results showed statistically significant differences between T2 Dixon and SPAIR (P < 0.01 in all). CONCLUSION: T2 Dixon sequence was superior to SPAIR for the quality of fat suppression and for the delineation of lumbar spine lesions.

Ruptured extracranial carotid artery: Endovascular treatment with covered stent graft.

BACKGROUND AND PURPOSE: Rupture of the extracranial carotid artery is a rare, but potentially disastrous event. We aimed to review the clinical presentations and radiologic findings of this entity and to evaluate the efficacy of endovascular treatment with covered stent graft. MATERIALS AND METHODS: Since January 2009, eight patients with extracranial carotid artery rupture received endovascular treatment with covered stent graft. We retrospectively reviewed their medical records and radiologic findings. RESULTS: The ruptured sites were in the common carotid artery (n=5), cervical ICA (n=2) and petrous ICA (n=1), respectively. The causes of injury included spontaneous (n=2), carotid blowout syndrome (CBS) (n=2), iatrogenic (n=2) and traumatic (n=2). Technical success and immediate hemostasis were achieved in all cases. Procedure-related complications occurred in 3 patients (37.5%). In a patient, the ipsilateral angular branch of the MCA was occluded during the procedure and it was completely reopened via mechanical thrombectomy without any neurologic deficit. Minor cerebral infarction was developed in 2 patients (25%). During a mean follow-up of 334 days (range 3-2053 days), two patients died: one from recurrent CBS and the other from aspiration pneumonia. CONCLUSIONS: The covered stent grafting is an effective method for the treatment of extracranial carotid artery rupture.

Splenial Lesions of the Corpus Callosum: Disease Spectrum and MRI Findings.

The corpus callosum (CC) is the largest white matter structure in the brain, consisting of more than 200-250 million axons that provide a large connection mainly between homologous cerebral cortical areas in mirror image sites. The posterior end of the CC is the thickest part, which is called the splenium. Various diseases including congenital to acquired lesions including congenital anomalies, traumatic lesions, ischemic diseases, tumors, metabolic, toxic, degenerative, and demyelinating diseases, can involve the splenium of the CC and their clinical symptoms and signs are also variable. Therefore, knowledge of the disease entities and the imaging findings of lesions involving the splenium is valuable in clinical practice. MR imaging is useful for the detection and differential diagnosis of splenial lesions of the CC. In this study, we classify the disease entities and describe imaging findings of lesions involving the splenium of the CC based on our experiences and a review of the literature.

Interpretations of diffusion-weighted MR imaging by radiology residents in the emergency department: is diagnostic performance influenced by the level of residency training?

BACKGROUND: To evaluate the diagnostic performance of radiology residents' interpretations for diffusion-weighted MR imaging (DWI) in the emergency department at different levels of residency training. METHOD AND MATERIALS: A total of 160 patients who underwent DWI with acute neurologic symptoms were included in this retrospective study with an institutional review board approval. Four radiology residents with different training years and one attending neuroradiologist independently assessed the DWI results. Discordances between the results of residents and attending neuroradiologist were classified as follows: false positive (FP) and false negative (FN). We also evaluated the diagnostic performance of four residents according to the reference standard. RESULTS: Overall, the concordance rate was 84.8 %, with a 15.2 % overall discordance rate. There were 83 FN results. The most common misses were small vessel disease (n = 55), acute focal infarction (n = 10), diffuse axonal injury (n = 6), solitary mass (n = 5), extraaxial hemorrhages (n = 3), posterior reversible encephalopathy syndrome (n = 2), and postictal change (n = 2). Fourteen FP results were interpreted as hemorrhage and acute infarction. The 4th year resident exhibited the highest diagnostic performance, and the level of training had a significant influence on the rates of concordance (P < 0.05). Interobserver reliability was good between the interpretations of the residents and the final interpretations of the attending neuroradiologists. CONCLUSION: The level of resident training had a significant effect on their diagnostic performance, and good interobserver reliability was noted between the results of the residents and attending neuroradiologist.

The oblique occipital sinus: anatomical study using bone subtraction 3D CT venography.

BACKGROUND AND PURPOSE: An occipital sinus draining into the sigmoid sinus has been termed the oblique occipital sinus (OOS). The frequency, anatomical features, patterns, and relationship with the transverse sinus of the oblique occipital sinus were analyzed in this study. MATERIALS AND METHODS: The study included 1805 patients who underwent brain CT angiography during a 3-year period from 2013 to 2015. CT examinations were performed using a 64-slice MDCT system. RESULTS: The OOS was identified in 41 patients (2.3%). There were many anatomical variations in the oblique occipital sinuses. A hypoplastic or aplastic TS was seen in 31 (75.6%) of the 41 patients with OOS. CONCLUSION: Many anatomical variations in the oblique occipital sinus can be seen on CT venography. Some OOSs function as the main drainage route of the intracranial veins instead of the TS. Thus, careful examination is essential for preoperative evaluation in posterior fossa lesions.

Lower Extremity Arterial Calcification as a Predictor of Coronary Atherosclerosis in Patients with Peripheral Arterial Disease.

BACKGROUND: Until now, there has been no study on the relationship between the calcification of the lower extremity arteries and significant coronary arterial disease (CAD). OBJECTIVES: To evaluate whether lower extremity calcium scores (LECS) are associated with CAD and whether this can predict multivessel-CAD in patients with peripheral arterial disease (PAD). PATIENTS AND METHODS: We retrospectively enrolled 103 PAD patients without cardiac symptoms or known CAD. All patients underwent cardiac computed tomography (CT) and lower extremity CT within 1 month and were categorized as nonsignificant CAD, single-CAD, or multivessel-CAD. The coronary calcium scores (CCS) were quantitatively measured according to the Agatston method and LECS were semi-quantitatively measured according to the presence of lower extremity calcification in the segment. The extent of CAD was evaluated according to the presence of ≥ 50% luminal diameter stenosis in the segment of CAD. RESULTS: LECS in multivessel-CAD were significantly higher than those in nonsignificant CAD (10.0 ± 5.8 versus 4.0 ± 3.1, P < 0.001). LECS significantly correlated with CCS (r = 0.831, P < 0.001) and the extent of CAD (r = 0.631, P < 0.001). Multivariate regression analysis demonstrated LECS and log-transformed CCS were independent predictors for multivessel-CAD. In receiver operating characteristic curve analysis, the diagnostic performance of LECS was 0.807 (95% confidence interval = 0.724-0.891, P < 0.001) for predicting multivessel-CAD. CONCLUSION: Peripheral arterial calcification is significantly correlated with CAD extent in patients with PAD. Peripheral arterial calcification can be a useful marker for predicting multivessel-CAD.

Duplication of the right vertebral artery: MRA findings and review of the literature.

INTRODUCTION: Duplication of the vertebral artery (VA) is a rare vascular variant. To the best our knowledge, only fourteen cases have been reported with angiographic findings that they have dual origin of the VA from ipsilateral subclavian artery. Herein, we present a case of duplication of right VA which was incidentally detected by magnetic resonance (MR) angiography. CASE DESCRIPTION: A 69-year-old female patient presented with headache for 30 days. She underwent brain MR imaging with MR angiography for evaluating possible intracranial cause. There was a dual origin of the right vertebral artery (VA) as an incidental finding without other significant abnormalities. DISCUSSION AND EVALUATION: Diagnosis of duplicated VA can be difficult due to its rarity and misinterpreted as the vascular dissection. In addition, a detailed knowledge of this variation is potentially important to prevent inadvertent challenges during endovascular procedure. Because duplicated VA has smaller lumen and usually enters the higher transverse foramen than those of normal side, it can be influence the choice or route of endovascular treatment. CONCLUSIONS: We suggested that the understanding of embryologic background about VA can be helpful to identify unexpected vascular findings on imaging studies in clinical practice.