Pushing the boundaries: circumferential endoscopic submucosal dissection in distal duodenum.

Video 1Pushing the boundaries: circumferential endoscopic submucosal dissection in distal duodenum (7.58 seconds).

Non-occlusive hepatic artery hypoperfusion syndrome and imaging findings: a systematic review.

Non-occlusive hepatic artery hypoperfusion syndrome (NHAHS), in other words, splenic steal, is a rare disorder that can arise following liver transplantation. After liver transplantation, its frequency has been defined as between 0.6 and 10.1%. The diversion of flow from hepatic to splenic arteries results in low perfused hepatic artery which causes elevated liver enzymes, hyperbilirubinemia, and graft dysfunction. This may result from a high resistance in the hepatic arteries, enlarged splenic arteries, a limited hepatic arterial flow due to high portal flow, or a discordance of the graft size and hepatic arterial flow. There may be a need for some prophylactic and/or posttransplant treatment procedures. We aimed to describe pre and post-treatment imaging findings of NHAHS.

Compressive Sonoelastography Findings of Esophageal Carcinoma.

OBJECTIVE: The aim of this study was to evaluate the compressive sonoelastography findings of primary esophageal carcinoma. MATERIALS AND METHODS: Esophageal specimens of the patients with a tumor staged earlier than T2, with no lymphadenopathy or distant metastasis, who underwent surgery, were evaluated by compressive sonoelastography under ex vivo conditions immediately following surgical excision. The compressive sonoelastography findings of primary esophageal carcinoma were recorded. Compressive sonoelastography measurements were made according to the esophageal muscle because of lack of fat tissue. RESULTS: The mean elasticity score was 3±1 (range, 1-4), and the mean strain ratio was 1±0.9 (range, 0.3-2.9). CONCLUSION: Primary esophageal carcinoma is stiff based on the elasticity score, and it demonstrated a mean strain ratio similar to the esophageal muscle.

Comparison of CT methods for determining graft steatosis in living donor liver transplantation.

PURPOSE: To evaluate and compare the diagnostic performance of non-enhanced computed tomography (NECT) and contrast-enhanced CT (CECT) attenuation indices in the assessment of hepatic steatosis by using biopsy as the reference standard. MATERIALS AND METHODS: This retrospective study was approved by our Institutional Review Board. 55 Potential donors who underwent both NECT and triphasic CECT and core liver biopsy, were included the study. Average attenuation measurements that were obtained from multiple regions in liver, spleen, and psoas muscle on both unenhanced and CECT were used for analysis. Hepatic attenuation measurements were analyzed with and without normalization with the spleen and psoas muscle. Linear regression and receiver operating characteristic (ROC) curve analysis were used to evaluate the statistical association between CT indices and steatosis at histology. RESULTS: Linear regression analysis confirmed the strongest correlation between steatosis and normalized measurements of hepatic attenuation with splenic attenuations on hepatic venous phase of CECT scan (R 0.821; R2 0.674 and R 0.816; R2 0.665, respectively). The use of ROC curve analysis also demonstrated that normalized measurements of hepatic attenuation with splenic attenuations on hepatic venous phase of CECT showed high diagnostic performance regarding the qualitative distinction of steatosis (AUC values greater than 0.9). CONCLUSION: Attenuation measurements of liver normalized with spleen on hepatic venous phase may be useful in evaluating steatosis in donor candidates with moderate to severe steatosis who are unacceptable for liver donation. In this manner unnecessary liver biopsy may be avoided in those donor candidates.

Diffusion-weighted imaging in ectopic pregnancy: ring of restriction sign.

OBJECTIVE: To demonstrate the diffusion-weighted imaging (DWI) findings of ectopic pregnancy (EP) and introduce the "ring of restriction" sign by discussing possible causes. METHODS: Between January 2014 and January 2017, patients with EP and examined by MRI on a 3T scanner were retrospectively evaluated. MRI and DWI findings were recorded. RESULTS: A total of 40 patients were diagnosed with EP at our university hospital, 8 of whom (20%) were evaluated by MRI and DWI. All of them were haemodynamically and clinically stable and could be imaged adequately. Locations were ovary (n = 3, 37.5%), tuba (n = 2, 25%), Caesarean section scar (n = 2, 25%) and parauterine (n = 1, 12.5%). In all eight EPs, the gestational sac diameter was compatible with 7-9 weeks. With DWI, the gestational sac was seen as a thick-walled cyst-like structure. The thick wall showed diffusion restrictions in all patients (ring of restriction sign). CONCLUSIONS: DWI through its cellular and molecular evidence may contribute diagnosis of EP. Advances in knowledge: Being aware of the EP wall shows diffusion restriction (ring of restriction) avoids interpretation errors especially in appropriate clinical setting with no need for contrast material.

Is the necrosis/wall ADC ratio useful for the differentiation of benign and malignant breast lesions?

OBJECTIVE: To determine whether the necrosis/wall apparent diffusion coefficient (ADC) ratio is useful for the malignant-benign differentiation of necrotic breast lesions. METHODS: Breast MRI was performed using a 3-T system. In this retrospective study, calculation of the necrosis/wall ADC ratio was based on ADC values measured from the necrosis and from the wall of malignant and benign breast lesions by diffusion-weighted imaging (DWI). By synchronizing post-contrast T1 weighted images, the separate parts of wall and necrosis were maintained. All the diagnoses were pathologically confirmed. Statistical analyses were conducted using an independent sample t-test and receiver operating characteristic analysis. The intraclass and interclass correlations were evaluated. RESULTS: A total of 66 female patients were enrolled, 38 of whom had necrotic breast carcinomas and 28 of whom had breast abscesses. The ADC values were obtained from both the wall and necrosis. The mean necrosis/wall ADC ratio (± standard deviation) was 1.61 ± 0.51 in carcinomas, and it was 0.65 ± 0.33 in abscesses. The area under the curve values for necrosis ADC, wall ADC and the necrosis/wall ADC ratio were 0.680, 0.068 and 0.942, respectively. A wall/necrosis ADC ratio cut-off value of 1.18 demonstrated a sensitivity of 97%, specificity of 93%, a positive-predictive value of 95%, a negative-predictive value of 96% and an accuracy of 95% in determining the malignant nature of necrotic breast lesions. There was a good intra- and interclass reliability for the ADC values of both necrosis and wall. CONCLUSION: The necrosis/wall ADC ratio appears to be a reliable and promising tool for discriminating breast carcinomas from abscesses using DWI. Advances in knowledge: ADC values of the necrosis obtained by DWI are valuable for malignant-benign differentiation in necrotic breast lesions. The necrosis/wall ADC ratio appears to be a reliable and promising tool in the breast imaging field.

Is it better to include necrosis in apparent diffusion coefficient (ADC) measurements? The necrosis/wall ADC ratio to differentiate malignant and benign necrotic lung lesions: Preliminary results.

PURPOSE: To determine whether the use of necrosis/wall apparent diffusion coefficient (ADC) ratios in the differentiation of necrotic lung lesions is more reliable than measuring the wall alone. MATERIALS AND METHODS: In this retrospective study, a total of 76 patients (54 males and 22 females, 71% vs. 29%, with a mean age of 53 ± 18 years, range, 18-84) were enrolled, 33 of whom had lung carcinoma and 43 had a benign necrotic lung lesion. A 3T scanner was used. The calculation of the necrosis/wall ADC ratio was based on ADC values measured from necrosis and the wall of the lesions by diffusion-weighted imaging (DWI). Statistical analyses were performed with the independent samples t-test and receiver operating characteristic analysis. Intraobserver and interobserver reliability were calculated for ADC values of wall and necrosis. RESULTS: The mean necrosis/wall ADC ratio was 1.67 ± 0.23 for malignant lesions and 0.75 ± 0.19 for benign lung lesions (P < 0.001). To estimate malignancy the area under the curve (AUC) values for necrosis ADC, wall ADC, and the necrosis/wall ADC ratio were 0.720, 0.073, and 0.997, respectively. A wall/necrosis ADC ratio cutoff value of 1.12 demonstrated a 100% sensitivity and 98% specificity in the estimation of malignancy. Positive predictive value was 100%, and negative predictive value 98% and diagnostic accuracy 99%. There was a good intraobserver and interobserver reliability for wall and necrosis. CONCLUSION: The necrosis/wall ADC ratio appears to be a reliable and promising tool for discriminating lung carcinoma from benign necrotic lung lesions than measuring the wall alone. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1001-1006.

The Use of Breast Magnetic Resonance Imaging Parameters to Identify Possible Signaling Pathways of a Serum Biomarker, HE4.

OBJECTIVES: This study aimed to investigate the relationship between breast magnetic resonance imaging (MRI) parameters; clinical features such as age, tumor diameter, N, T, and TNM stages; and serum human epididymis protein 4 (HE4) levels in patients with breast carcinoma and use this as a means of estimating possible signaling pathways of the biomarker, HE4. METHODS: Thirty-seven patients with breast cancer were evaluated by breast MRI and serum HE4 levels before therapy. Correlations between parameters including age, tumor diameter T and N, dynamic curve type, enhancement ratio (ER), slope washin (S-WI), time to peak (TTP), slope washout (S-WO), and the serum level of HE4 were investigated statistically. Human epididymis protein 4 levels of early and advanced stage of disease were also compared statistically. RESULTS: Breast MRI parameters showed correlation to serum HE4 levels and correlations were statistically significant. Of these MRI parameters, S-WI had higher correlation coefficient than the others. Human epididymis protein 4 levels were not statistically different in early and advanced stage of disease. CONCLUSIONS: High correlation with MRI parameters related to neoangiogenesis may indicate signaling pathway of HE4.

A novel approach to contrast-induced nephrotoxicity: the melatonergic agent agomelatine.

OBJECTIVE: To study the potential nephroprotective role of agomelatine in rat renal tissue in cases of contrast-induced nephrotoxicity (CIN). The drug's action on the antioxidant system and proinflammatory cytokines, superoxide dismutase (SOD) activity, levels of glutathione (GSH) and malondialdehyde (MDA) and the gene expression of interleukin-6 (IL-6), tumour necrosis factor (TNF)-α and nuclear factor kappa B (NF-κB) was measured. Tubular necrosis and hyaline and haemorrhagic casts were also histopathologically evaluated. METHODS: The institutional ethics and local animal care committees approved the study. Eight groups of six rats were put on the following drug regimens: Group 1: healthy controls, Group 2: GLY (glycerol), Group 3: CM (contrast media--iohexol 10 ml kg(-1)), Group 4: GLY+CM, Group 5: CM+AGO20 (agomelatine 20 mg kg(-1)), Group 6: GLY+CM+AGO20, Group 7: CM+AGO40 (agomelatine 40 mg kg(-1)) and Group 8: GLY+CM+AGO40. The groups were evaluated by one-way analysis of variance and Duncan's multiple comparison test. RESULTS: Agomelatine administration significantly improved the serum levels of blood urea nitrogen (BUN) and creatinine, SOD activity, GSH and MDA. The use of agomelatine had substantial downregulatory consequences on TNF-α, NF-κB and IL-6 messenger RNA levels. Mild-to-severe hyaline and haemorrhagic casts and tubular necrosis were observed in all groups, except in the healthy group. The histopathological scores were better in the agomelatine treatment groups. CONCLUSION: Agomelatine has nephroprotective effects against CIN in rats. This effect can be attributed to its properties of reducing oxidative stress and inhibiting the secretion of proinflammatory cytokines (NF-κB, TNF-α and IL-6). ADVANCES IN KNOWLEDGE: CIN is one of the most important adverse effects of radiological procedures. Renal failure, diabetes, malignancy, old age and non-steroidal anti-inflammatory drug use pose the risk of CIN in patients. Several clinical studies have investigated ways to avoid CIN. Theophylline/aminophylline, statins, ascorbic acid and iloprost have been suggested for this purpose. Agomelatine is one of the melatonin ligands and is used for affective disorders and has antioxidant features. In this study, we hypothesized that agomelatine could have nephroprotective, antioxidant and anti-inflammatory effects against CIN in rats.

Osteochondral Lesions of Major Joints.

This paper provides information about osteochondral lesions (OCL) and example cases of OCL occurring in major joints, some of which are rarely seen. This simple tutorial is presented in question and answer format.

Unilateral Optic Neuropathy and Acute Angle-Closure Glaucoma following Snake Envenomation.

Purpose. We aimed to describe a unique case in which a patient developed unilateral optic neuritis and angle-closure glaucoma as a result of snake envenomation. Case Report. Approximately 18 hours after envenomation, a 67-year-old female patient described visual impairment and severe pain in her left eye (LE). The patient's best corrected visual acuity was 10/10 in the RE and hand motion in the LE. Cranial magnetic resonance imaging showed signs of neuropathy in the left optic nerve. In the LE, corneal haziness, closure of the iridocorneal angle, and mild mydriasis were observed and pupillary light reflex was absent. Intraocular pressure was 25 mmHg and 57 mmHg in the RE and LE, respectively. The patient was diagnosed with acute angle-closure glaucoma in the LE. Optic neuropathy was treated with intravenous pulse methylprednisolone. Left intraocular pressure was within normal range starting on the fourth day. One month after the incident, there was no sign of optic neuropathy; relative afferent pupillary defect and optic nerve swelling disappeared. Conclusions. Patients with severe headache and visual loss after snake envenomation must be carefully examined for possible optic neuropathy and angle-closure glaucoma. Early diagnosis and treatment of these cases are necessary to prevent permanent damage to optic nerves.

Sonoelastography findings for idiopathic granulomatous mastitis.

OBJECTIVES: In this paper we describe sonoelastography findings for idiopathic granulomatous mastitis (IGM), the clinical and radiological features of which often mimic those of breast carcinoma. MATERIALS AND METHODS: In this retrospective study, sonoelastography findings for patients with pathologically proved IGM were studied. Twenty-seven patients with pathologically proved IGM were enrolled in the study. All were female, and the mean age was 37.81 years (standard deviation 7.10 years; range 24 to 56 years). Elasticity scores (ES), strain ratios (SR), and elastic diameters (ED) were evaluated for the lesions. RESULTS: Ten lesions (37.0 %) were diffuse, six (22.2 %) were tubular, six (22.2 %) were a mass, and five (18.5 %) were cystic in appearance on ultrasonography. On sonoelastography, mean ES ± standard deviation was 1.66 ± 0.55 (between 1.00 and 3.00); mean SR ± standard deviation was 1.10 ± 0.79 (between 0.29 and 4.00). ED was no different between grey-scale and sonoelastogram images. CONCLUSIONS: The features of idiopathic granulomatous mastitis suggest it is benign in nature.

Value of MRI sequences for prediction of invasive breast carcinoma size.

INTRODUCTION: In this retrospective study, we compared transverse short tau inversion recovery (STIR), transverse diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) map and first post-contrast fat-saturated fast low-angle shot (FLASH) 3D T1 with pathology results in terms of their accuracy in estimating breast carcinoma size. METHODS: Magnetic resonance imaging data for 47 patients with invasive breast carcinoma, who were treated surgically, were reviewed. The longest dimension (LD) of the index lesion was measured using STIR, DWI, ADC map and first post-contrast FLASH 3D T1, and this was compared with the LD measured on the pathology specimen. RESULTS: All four MRI sequences overestimated the LD by an average of about 1 mm with 95% limits of agreement approximately 0 to 2 mm. This is not considered to be clinically significant in tumours of 10 mm or larger. CONCLUSION: Magnetic resonance imaging serves as an accurate tool in sizing breast carcinomas. ADC may be a useful evaluation tool for sizing carcinomas without requiring contrast material.

Breast lesions with high signal intensity on T1-weighted MR images.

Magnetic resonance imaging of the breast supplies much information concerning the signal characteristics of a lesion. Among these, high signal intensity on non-fat saturated T1-weighted imaging (WI) is a special finding. Such a finding may result from different causes, such as a paramagnetic substance or fatty, bloody or proteinaceous content. In this article, we present hyperintense breast lesions on T1-WI.

Comparison of 16-slice computed tomography with conventional angiography to evaluate coronary artery stent patency.

OBJECTIVE: In this study, we evaluated the utility of 16-slice MDCT (multidetector computed tomography) to assess stent patency after coronary artery stenting. MATERIALS AND METHODS: Retrospective ECG-gated CT-angiography using 16-slice MDCT was performed in 52 consecutive patients with coronary artery stents. Qualitative assessment of 61 coronary stent lumens by MDCT is reported, and the reasons preventing assessment were investigated. RESULTS: All non-assessable stents were non-assessable due to partial volume effects and metal artifacts. To evaluate instent restenosis, conventional coronary angiography was performed on the 54 assessable stents in 48 patients, and the results were compared with the MDCT results. Based on the results of the conventional coronary angiography, MDCT correctly detected four in-stent restenosis. CONCLUSION: Despite some limitations, 16-slice MDCT provides sufficient evaluations of some coronary stents, and can detect in-stent restenosis with high accuracy.

Absence of the Left Main Coronary Artery: MDCT Coronary Angiographic Imaging.

Absent left main coronary artery (LMCA) is a rare congenital cardiac malformation. We present a case report of a 65-year-old woman with anomalous origin of the left anterior descending (LAD) and circumflex (LCx) artery separated from the left sinus of Valsalva that was diagnosed by multi-detector row computed tomography (MDCT) coronary angiography. Our case indicates that MDCT plays an important role in the diagnosis of some rare coronary anomalies.