Diffusion-weighted MRI of pulmonary lesions: Comparison of apparent diffusion coefficient and lesion-to-spinal cord signal intensity ratio in lesion characterization.

PURPOSE: To evaluate the diagnostic performance of minimum apparent diffusion coefficient (ADCmin ) and lesion-to-spinal cord signal intensity ratio (LSR) in the differentiation of benign and malignant pulmonary lesions. MATERIALS AND METHODS: Forty-seven patients (36 men, 11 women; range, 17-81 years) with 62 pulmonary lesions underwent magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) performed using a 1.5T scanner during free-breathing using b 600 s/mm2 . The ADCmin values and LSR were calculated. A receiver operating characteristic (ROC) curve analysis was performed to detect the threshold value of the ADCmin and LSR values for discrimination between benign and malignant pulmonary lesions. RESULTS: There were 42 malignant (33 primary tumors, 9 metastases) and 20 benign lesions. The mean ADCmin ± standard deviations (×10-3 mm2 /s) were 1.45 ± 0.33 for malignant tumors, and 2.4 ± 0.69 for benign lesions (P < 0.001). The mean LSR ± standard deviations for lung cancer was 1.24 ± 0.78, and for benign lesions was 0.55 ± 0.57 (P < 0.001). The area under the ROC curve for ADCmin (0.931; 95% confidence interval [CI]: 0.868-0.993) was greater than that for LSR (0.801; 95% CI: 0.675-0.926) (P = 0.029). For benign/malignant discrimination, the ROC curve showed threshold value of ADCmin to be 1.78 × 10-3 mm2 /s and that of LSR to be 0.86. Using these cutoff values, accuracy of ADCmin and LSR were 89%, 74%, respectively (P = 0.383). CONCLUSION: Being a contrast-free and radiation-free technique, DWI allows discrimination of benign and malignant lung lesions. The ADCmin value performed marginally better than LSR values in distinction of benign and malignant lesions. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:845-854.

Inaccurate Citations in Biomedical Journalism: Effect on the Impact Factor of the American Journal of Roentgenology.

OBJECTIVE: The aim of this study is to investigate the frequency of incorrect citations and its effects on the impact factor of a specific biomedical journal: the American Journal of Roentgenology. MATERIALS AND METHODS: The Cited Reference Search function of Thomson Reuters' Web of Science database (formerly the Institute for Scientific Information's Web of Knowledge database) was used to identify erroneous citations. This was done by entering the journal name into the Cited Work field and entering "2011-2012" into the Cited Year(s) field. The errors in any part of the inaccurately cited references (e.g., author names, title, year, volume, issue, and page numbers) were recorded, and the types of errors (i.e., absent, deficient, or mistyped) were analyzed. Erroneous citations were corrected using the Suggest a Correction function of the Web of Science database. The effect of inaccurate citations on the impact factor of the AJR was calculated. RESULTS: Overall, 183 of 1055 citable articles published in 2011-2012 were inaccurately cited 423 times (mean [± SD], 2.31 ± 4.67 times; range, 1-44 times). Of these 183 articles, 110 (60.1%) were web-only articles and 44 (24.0%) were print articles. The most commonly identified errors were page number errors (44.8%) and misspelling of an author's name (20.2%). Incorrect citations adversely affected the impact factor of the AJR by 0.065 in 2012 and by 0.123 in 2013. CONCLUSION: Inaccurate citations are not infrequent in biomedical journals, yet they can be detected and corrected using the Web of Science database. Although the accuracy of references is primarily the responsibility of authors, the journal editorial office should also define a periodic inaccurate citation check task and correct erroneous citations to reclaim unnecessarily lost credit.

Unenhanced and Contrast-Enhanced MR Angiography and Perfusion Imaging for Suspected Pulmonary Thromboembolism.

OBJECTIVE: This article discusses the basics of unenhanced MR angiography (MRA) and MR venography (MRV), time-resolved contrast-enhanced (CE) MRA and dynamic first-pass CE perfusion MRI, and unenhanced and CE MRV, in addition to assessing the clinical relevance of these techniques for evaluating patients with suspected pulmonary thromboembolism and deep venous thrombosis. CONCLUSION: Since the 1990s, the efficacy of MRA or MRV and dynamic perfusion MRI for patients with suspected pulmonary thromboembolism and deep venous thrombosis has been evaluated. On the basis of the results of single-center trials, comprehensive MRI protocols, including pulmonary unenhanced and CE MRA, perfusion MRI, and MRV, promise to be safe and time effective for assessing patients with suspected pulmonary thromboembolism, although future multicenter trials are required to assess the real clinical value of MRI.

Association of real-time sonoelastography findings with clinical parameters in lateral epicondylitis.

The objective of this study was to investigate the role of real-time sonoelastography (RTSE) in patients with lateral epicondylitis (LE) and whether it is associated with clinical parameters. Seventeen patients with unilateral LE were enrolled in the study. The healthy elbows of the participants constituted the control group. Using B-mode ultrasound, color Doppler ultrasound, and RTSE, we prospectively examined 34 common extensor tendon elbows of 17 patients. Both color scales and strain ratio were used for evaluating RTSE images. Two radiologists evaluated the RTSE images separately. Elbow pain was scored on a 100-mm visual analog scale (VAS). Symptom duration and the presence of nocturnal pain were questioned. Quick disabilities of arm shoulder and hand (DASH) Questionnaire was applied to assess the pain, function, and disability. Nottingham health profile (NHP) was used to determine and quantify perceived health problems. Both color scales and strain ratios of the affected tendon portions were significantly different from that of healthy tendons (p < 0.001). There was no significant association between NHP, VAS, Quick DASH scores, and color scales and strain ratio. Strain ratio of the medial portion of the affected tendon was significantly correlated with symptom duration (rho = -0.61 p = 0.010) and nocturnal pain (rho = 0.522 p = 0.031). Interobserver agreement was substantial for color scales (κ = 0.74, p = 0.001) and strain ratio (ICC = 0.61, p = 0.031). RTSE may facilitate differentiation between healthy and affected elbows as a feasible and practical supplementary method with substantial interobserver agreement. RTSE was superior to B-mode ultrasound and color Doppler ultrasound in discriminating tendons with LE. Strain ratio of the medial portion of the tendon is associated moderately with nocturnal pain and symptom duration. No other associations were present between RTSE findings and clinical or functional parameters.

Pylephlebitis Complicating Acute Appendicitis: Prompt Diagnosis with Contrast-Enhanced Computed Tomography.

BACKGROUND: Pylephlebitis, a rare complication of abdominal infections, is a septic thrombophlebitis of the portal venous system with high rates of morbidity and mortality. CASE REPORT: We present a case of pylephlebitis complicating acute appendicitis and report the utility of a computed tomography scan in the diagnosis. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The prompt diagnosis and appropriate treatment of pylephlebitis are crucial to reduce morbidity and mortality, but clinical presentation is often nonspecific. A computed tomography scan is instrumental in the early diagnosis of pylephlebitis because it readily reveals the thrombus in the mesenteric or portal vein in the setting of acute appendicitis. Early and aggressive treatment with broad-spectrum antibiotics is necessary, and anticoagulation therapy can also be used to prevent bowel ischemia.

Evaluation of Free Breathing Versus Breath Hold Diffusion Weighted Imaging in Terms Apparent Diffusion Coefficient (ADC) and Signal-to-Noise Ratio (SNR) Values for Solid Abdominal Organs.

BACKGROUND: Our aim was to compare the apparent diffusion coefficient (ADC) values of normal abdominal parenchymal organs and signal-to-noise ratio (SNR) measurements in the same patients with breath hold (BH) and free breathing (FB) diffusion weighted imaging (DWI). MATERIAL/METHODS: Forty-eight patients underwent both BH and FB DWI. Spherical region of interest (ROI) was placed on the right hepatic lobe, spleen, pancreas, and renal cortices. ADC values were calculated for each organ on each sequence using an automated software. Image noise, defined as the standard deviation (SD) of the signal intensities in the most artifact-free area of the image background was measured by placing the largest possible ROI on either the left or the right side of the body outside the object in the recorded field of view. SNR was calculated using the formula: SNR=signal intensity (SI)(organ)/standard deviation (SD)(noise). RESULTS: There were no statistically significant differences in ADC values of the abdominal organs between BH and FB DWI sequences (p>0.05). There were statistically significant differences between SNR values of organs on BH and FB DWIs. SNRs were found to be better on FB DWI than BH DWI (p<0.001). CONCLUSIONS: Free breathing DWI technique reduces image noise and increases SNR for abdominal examinations. Free breathing technique is therefore preferable to BH DWI in the evaluation of abdominal organs by DWI.

Correlation of diffusion MRI with the Ki-67 index in non-small cell lung cancer.

BACKGROUND: The primary objective of the study was to evaluate the association between the minimum apparent diffusion coefficient (ADCmin) and Ki-67, an index for cellular proliferation, in non-small cell lung cancers. Also, we aimed to assess whether ADCmin values differ between tumour subtypes and tissue sampling method. METHODS: The patients who had diffusion weighted magnetic resonance imaging (DW-MRI) were enrolled retrospectively. The correlation between ADCmin and the Ki-67 index was evaluated. RESULTS: Ninety three patients, with a mean age 65 ± 11 years, with histopathologically proven adenocarcinoma and squamous cell carcinoma of the lungs and had technically successful DW-MRI were included in the study. The numbers of tumour subtypes were 47 for adenocarcinoma and 46 for squamous cell carcinoma. There was a good negative correlation between ADCmin values and the Ki-67 proliferation index (r = -0.837, p < 0.001). The mean ADCmin value was higher and the mean Ki-67 index was lower in adenocarcinomas compared to squamous cell carcinoma (p < 0.0001). There was no statistical difference between tissue sampling methods. CONCLUSIONS: Because ADCmin shows a good but negative correlation with Ki-67 index, it provides an opportunity to evaluate tumours and their aggressiveness and may be helpful in the differentiation of subtypes non-invasively.

Inflammatory Myofibroblastic Tumor of the Lung: Unusual Imaging Findings of Three Cases.

BACKGROUND: Inflammatory myofibroblastic tumor (IMT), also known as inflammatory pseudotumor, is a benign disorder composed of fibrous tissues, myofibroblasts and inflammatory cell proliferation with obscure etiology. Although it is the most common lung tumor in children, it is seen rarely in adults constituting less than 1% of adult lung tumors. CASE REPORTS: In this report, we present different and rare CT manifestations of three adult patients with lung IMT. CONCLUSIONS: In conclusion, IMT is a rare lung tumor in adults and may simulate malignancy. It should be considered in the differential diagnosis when a large mass with lobulated contour or harboring coarse calcification is observed.

Efficacy of magnetic resonance urography in detecting renal scars in children with vesicoureteral reflux.

BACKGROUND: The detection of renal scars is of paramount importance for optimal clinical management of patients with urinary tract infection (UTI) and vesicoureteral reflux (VUR). The aim of our study was to compare the efficacy of unenhanced magnetic resonance urography (MRU) and Tc-99(m) dimercaptosuccinic acid (Tc-DMSA) scintigraphy to dectect renal scars. METHODS: Unenhanced MRU and Tc-DMSA scintigraphy were performed in 49 children (10 boys, 39 girls; mean age 7.4 ± 4.2 years, range 1-15 years) with documented VUR. MR imaging scans were obtained within 7 days after voiding cystourethrogram (VCUG) and Tc-DMSA scintigraphy. The diagnostic performance of MRU in renal scar detection was calculated relative to that of the Tc-DMSA scan. RESULTS: The renal scar detection rate of Tc-DMSA scintigraphy and unenhanced MRU in kidneys with VUR was 32.4 and 25.9%, respectively. The sensitivity and specificity of MRU in the detection of renal scars was 80 and 82.6% in kidneys with VUR, respectively. There was no statistically significant difference in lesion detection between MRU and Tc-DMSA scintigraphy (P > 0.05). MRU and Tc-DMSA scintigraphy showed good agreement (κ = 0.60). CONCLUSIONS: Unenhanced MRU is a robust technique for the morphologic assessment of the urinary system and detection of renal scars. The lack of radiation and contrast material makes this technique a much safer alternative to scintigraphy in children with VUR, particularly in those who require follow-up scanning and, consequently, considerable radiation exposure.

Non-invasive detection of biliary leaks using Gd-EOB-DTPA-enhanced MR cholangiography: comparison with T2-weighted MR cholangiography.

OBJECTIVE: To evaluate the added role of T1-weighted (T1w) gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance cholangiography (MRC) compared with T2-weighted MRC (T2w-MRC) in the detection of biliary leaks. METHODS: Ninety-nine patients with suspected biliary complications underwent routine T2w-MRC and T1w contrast-enhanced (CE) MRC using Gd-EOB-DTPA to identify biliary leaks. Two observers reviewed the image sets separately and together. MRC findings were compared with those of surgery and percutaneous transhepatic cholangiopancreatography. The sensitivity, specificity and accuracy of the techniques in identifying biliary leaks were calculated. RESULTS: Accuracy of locating biliary leaks was superior with the combination of Gd-EOB-DTPA-enhanced MRC and T2w-MRC (P < 0.05).The mean sensitivities were 79 % vs 59 %, and the mean accuracy rates were 84 % vs 58 % for combined CE-MRC and T2w-MRC vs sole T2w-MRC. Nineteen out of 21 patients with biliary-cyst communication, 90.4 %, and 12/15 patients with post-traumatic biliary extravasations, 80 %, were detected by the combination of Gd-EOB-DTPA-enhanced MRC and T2w-MRC images, P < 0.05. CONCLUSIONS: Gd-EOB-DTPA-enhanced MRC yields information that complements T2w-MRC findings and improves the identification and localisation of the bile extravasations (84 % accuracy, 100 % specificity, P < 0.05). We recommend Gd-EOB-DTPA-enhanced MRC in addition to T2w-MRC to increase the preoperative accuracy of identifying and locating extravasations of bile. KEY POINTS: • Magnetic resonance cholangiography (MRC) does not always detect bile leakage and cysto-biliary communications. • Gd-EOB-DTPA-enhanced MRC helps by demonstrating extravasation of contrast material into fluid collections. • Gd-EOB-DTPA-enhanced MRC also demonstrates the leakage site and bile duct injury type. • Combined Gd-EOB-DTPA-enhanced and T2w-MRC can provide comprehensive information about biliary system. • Gd-EOB-DTPA-enhanced MRC is non-invasive and does not use ionising radiation.

A single-center large-volume experience in the surgical management of hydatid disease of the lung with and without extrapulmonary involvement.

BACKGROUND: We compared the number of incisions, surgical procedures, hospital duration, and complications in hydatid cyst patients with unilateral or bilateral thoracic involvement and concomitant involvement of the extrathoracic organs. METHODS: A total of 76 hydatid cyst cases surgically treated between the years 2007 and 2012 were divided into three groups according to radiological evidence of other organ involvement and surgical procedures: group 1 had only unilateral thoracic involvement and a single incision; group 2 had additional involvement of the contralateral thoracic side or extrathoracic organs and at most two incisions were performed at the same session; and group 3 had two or more incisions performed at separate sessions in addition to the involvement features of group 2. RESULTS: We had 46 (60.5 %) cases with only thoracic involvement and 30 others (39.5 %) with extrathoracic organ involvement. Complications were seen in only one patient each in the first and second groups, and in 6 patients in the third group. Duration of hospital stay was 7.04 ± 0.86 (5-9) days in group 1.8.33 ± 1.87 (7-13) days in group 2, and 13.95 ± 2.03 (9-18) days in group 3. CONCLUSIONS: Although multiple session surgery is used to decrease the risk of complications, contamination, and infection in multiple or bilateral pulmonary hydatid cyst cases, or in patients with other organ involvement, single-session surgery can be used in selected cases taking into account the operative trauma, financial consequences, and psychological profile.

Alveolar echinococcosis: spectrum of findings at cross-sectional imaging.

Alveolar echinococcosis is a rare parasitic disease caused by the fox tapeworm Echinococcus multilocularis, which is endemic in many parts of the world. Without timely diagnosis and therapy, the prognosis is dismal, with death the eventual outcome in most cases. Diagnosis is usually based on findings at radiologic imaging and in serologic analyses. Because echinococcal lesions can occur almost anywhere in the body, familiarity with the spectrum of cross-sectional imaging appearances is advantageous. Echinococcal lesions may produce widely varied imaging appearances depending on the parasite's growth stage, the tissues or organs affected, and the presence of associated complications. Although the liver is the initial site of mass infestation by E multilocularis, the parasite may disseminate from there to other organs and tissues, such as the lung, heart, brain, bones, and ligaments. In severe infestations, the walls of the bile ducts and blood vessels may be invaded. Disseminated parasitic lesions in unusual locations with atypical imaging appearances may make it difficult to narrow the differential diagnosis. Ultrasonography, computed tomography (CT), magnetic resonance (MR) imaging with standard and diffusion-weighted sequences, and MR cholangiopancreatography all provide useful information and play complementary roles in detecting and characterizing echinococcal lesions. Cross-sectional imaging is crucial for differentiating echinococcosis from malignant processes: CT is most useful for depicting the peripheral calcifications surrounding established echinococcal cysts, and MR imaging is most helpful for identifying echinococcosis of the central nervous system.

Bilateral symmetric junctional infarctions of the cerebellum: a case report.

The advances in neuroimaging have improved clinicoanatomic correlations in patients with stroke. Junctional infarct is a distinct term, used to describe border zone infarcts of the posterior fossa. We presented computed tomography (CT) and magnetic resonance imaging (MRI) findings in a rare case of bilateral symmetrical junctional infarcts between the superior cerebellar artery (SCA) and posterior inferior cerebellar artery (PICA) territories. In addition to precise knowledge of arterial territories required to achieve accurate localization of ischemic lesions on CT and MRI, the radiologist must also be aware of radiologic features and geographic territories of cerebellar arteries and their junctional infarctions.

Giant arachnoid granulation in a patient with benign intracranial hypertension (2009: 1b).

We report magnetic resonance (MR), computed tomography (CT) and angiographic imaging of an unusual giant arachnoid granulation 7(GAG) in the superior sagittal sinus in a man with headache and vertigo. Intrasinus pressure measurements revealed a significant pressure gradient across the lesion. MR imaging is useful to identify GAG and dural sinus thrombosis, whereas dural sinus pressure measurement in certain cases of GAGs can be used to evaluate the lesion as the cause of the patient's symptoms.

Diagnostic performance of contrast-enhanced and unenhanced combined pulmonary artery MRI and magnetic resonance venography techniques in the diagnosis of venous thromboembolism.

OBJECTIVE:: We aimed to determine the diagnostic performance of the contrast-enhanced and unenhanced combined pulmonary arterial MRI and magnetic resonance venography techniques in the diagnosis of venous thromboembolism (VTE). METHODS:: 44 patients who underwent CT pulmonary angiography (CTPA) for suspected PE constituted the study population. Patients underwent combined pulmonary and lower extremity MRI, and Doppler ultrasonography within 72 h after CTPA. Combined MRI included two sequences: unenhanced steady-state free precession (SSFP) and contrast-enhanced three-dimensional (3D) gradient echo (GRE). The presence of emboli in pulmonary arteries and thrombi in lower extremity veins on 3D-GRE and SSFP sequences was recorded. RESULTS:: CTPA showed a total of 244 emboli in 33 (75%) patients whereas contrast-enhanced 3D-GRE MRI showed deep vein thrombosis (DVT) in 34 (77%) subjects. Sensitivities for SSFP vs 3D-GRE MRI respectively in PE detection were 87.9 vs 100% on a per-patient basis, and 53.7 vs 73% on a per-embolus basis. Of 34 patients with established DVT, 31 (91%) were detected by Doppler ultrasound and 29 (85%) were detected by SSFP technique respectively. CONCLUSION:: Both contrast-enhanced and unenhanced combined MRI of acute PE and DVT are feasible one-stop-shopping techniques in patients with suspected thromboembolism. ADVANCES IN KNOWLEDGE:: Pulmonary VTE is a common disease with high mortality. Non-invasive techniques withhigh accuracy are required for the assessment of VTE. CT-related radiation and contrast material risks cause concerns. MRI is a radiation-free technique evaluating the vessels with and without contrast. Combined contrast enhancedor unenhanced pulmonary and lower extremity MRI is feasible in patients with suspected thromboembolism.