Sureyya Burcu Gorkem

Evaluation of Pediatric Thoracic Disorders: Comparison of Unenhanced Fast-Imaging-Sequence 1.5-T MRI and Contrast-Enhanced MDCT

OBJECTIVE The purpose of this study was to investigate the efficacy of thoracic MRI with fast imaging sequences without contrast administration at 1.5 T for evaluating thoracic abnormalities by comparing MRI findings with contrast-enhanced MDCT findings. SUBJECTS AND METHODS A prospective study included consecutively registered pediatric patients who from December 2009 to January 2012 underwent thoracic MDCT followed within 2 days by MRI for evaluation of thoracic abnormalities. The final study sample consisted of 71 children (36 boys, 35 girls; mean age, 8.6 ± 4.5 years; range, 2 months-16 years) and 71 paired thoracic MRI and MDCT studies. Thoracic MRI was performed in the axial and coronal planes with the following fast imaging sequences: T1-weighted fast-field echo inversion prepulse, T2-weighted balanced fast-field echo multiple 2D, T1- and T2-weighted turbo spin-echo cardiac-triggering parallel imaging technique without cardiac monitoring, and STIR. Thoracic MDCT was performed with i.v. contrast administration. Two pediatric radiologists independently reviewed each MRI and MDCT study for abnormalities in the lung, large airways, and mediastinal, pleural, and musculoskeletal structures. The sensitivity, specificity, and overall accuracy of MRI were calculated. Interobserver agreement was measured with the kappa coefficient. RESULTS With MDCT as the reference standard, 51 of 71 (72%) patients had abnormal findings on MDCT studies, including infections in 21 (42%) cases, neoplasms in 19 (37%) cases, interstitial lung disease in seven (14%) cases, pleural effusion in three (6%) cases, and congenital bronchogenic cyst in one (2%) case. The overall diagnostic accuracy, sensitivity, and specificity of MRI for detecting thoracic abnormalities were 69 of 71 (97%), 49 of 51 (96%), and 20 of 20 (100%). Two undiagnosed findings with MRI that were detected with MDCT were mild bronchiectasis and small pulmonary nodule (3 mm). Almost perfect interobserver agreement was found between two reviewers with 70 of 71 agreements (κ = 0.97; 95% CI, 0.92-1.00; p < 0.001). CONCLUSION; MRI with fast imaging sequences without contrast administration is comparable to contrast-enhanced MDCT for detecting thoracic abnormalities in pediatric patients. Use of MRI with fast imaging sequences without contrast administration as a first-line cross-sectional imaging study in lieu of contrast-enhanced MDCT has the potential to benefit this patient population owing to reduced radiation exposure and i.v. contrast administration.

Susceptibility-Based Differentiation of Intracranial Calcification and Hemorrhage in Pediatric Patients.

Differential diagnosis of intracranial hemorrhage versus calcification on conventional magnetic resonance images (MRIs) is often challenging. Although computed tomography (CT) confirms calcification, phase information obtained during susceptibility-weighted imaging can be useful in distinguishing between 2 pathologies. Fourteen patients previously diagnosed to have hemorrhage or calcification with imaging were included in the study retrospectively. Phase shift values of hemorrhage and calcification were compared by using Student t test. The pathologies identified were tuberous sclerosis, Sturge-Weber syndrome, craniopharyngioma, congenital cytomegalovirus, subependymal hemorrhages, and hemorrhagic microembolic infarction. Calcifications appeared hypointense whereas hemorrhages were hyperintense on phase maps (left-handed magnetic resonance system). Statistical comparison of phase shift values yielded significant difference between hemorrhage versus calcification (P < .01). Phase maps were found to offer valuable data to differentiate 2 pathologies when used complementary to conventional magnetic resonance images. Considering the relatively higher risks of radiation exposure in children, susceptibility-weighted imaging with phase maps may help to waive radiation exposure from CT.

Abnormal axillary lymph nodes on negative mammograms: causes other than breast cancer.

Enlargement of lymph nodes can be due to a variety of benign and malignant causes. The most common malignant cause is invasive ductal carcinoma, which is usually visualized with mammography. Excluding breast cancer, other causes of abnormal lymph nodes that produce a negative mammogram include lymphoma, metastases from other malignancies, and benign etiologies such as inflammatory processes, infectious diseases, collagen vascular diseases, and miscellaneous causes. In this essay, we described common causes of abnormal axillary lymph nodes on negative mammograms excluding breast cancer.

Thoracic MRI evaluation of sarcoidosis in children.

Childhood sarcoidosis is a very rare granulomatous disorder with an unknown etiology. Stage 1 disease is the most common whereas stages 2, 3, and 0 are rare in children.

Preferences of referring physicians regarding the role of radiologists as direct communicators of test results.

PURPOSE Currently, there is a growing need for patient-centered radiology in which radiologists communicate with patients directly. The aim of this study is to investigate the preferences of referring physicians (RPs) regarding direct communication between radiologists and patients. METHODS This study was conducted in a single academic hospital using a survey form. The survey items investigated the preferences of RPs regarding: 1. who should be the communicator of test results when a patient with abnormal findings requests information (the options were the radiologist; another health professional with communication skills training (CST); and the RP with CST); and 2. how the communication activity should be conducted if the radiologist is obliged (or chooses) to communicate with the patient directly (the options were that the disclosure should be limited to the findings in the radiology report; the radiologist should emphasize that the RP is the primary physician; and the communication activity should be conducted in accordance with guidelines established by consensus). The respondents were 101 RPs from various fields of specialty; they were asked to rate the items using a 5-point Likert scale. The effects of age, sex, field of specialty (surgical vs. nonsurgical), and total years of experience as a medical specialist on the ratings were statistically compared. RESULTS Most RPs preferred that the radiologist transmit the information to the RP without communicating directly with the patient (89.1%). Although 69.3% of the RPs declared that health professionals with CST have priority in communication, 86.1% declared that the RP should be the person who received CST. If the radiologist communicates with patients directly, the RPs favored that 1. the disclosure should be limited to the findings in the radiology report (95%); 2. the communication activity should include an emphasis on the RP as the patients primary agent (84.1%); and 3. communication should be conducted in accordance with guidelines established by consensus (73.2%). The percentage of strong opinions did not change significantly with regard to age, sex, field of specialty, or total years of experience, except that surgeons expressed strong disagreement with delegating the communication activity to another health professional who received CST (χ² = 9.9; P = 0.042). CONCLUSION These findings may serve as a basis to implement institutional and national policies for patient-centered radiology.

Diagnosis of intracranial calcification and hemorrhage in pediatric patients: Comparison of quantitative susceptibility mapping and phase images of susceptibility-weighted imaging

PURPOSE To prospectively compare the diagnostic capabilities of quantitative susceptibility mapping (QSM) with those of phase images of susceptibility-weighted imaging (SWI) in the detection and differentiation of intracranial calcification and hemorrhage in pediatric patients. METHOD Sixteen pediatric patients (9 girls, 7 boys) with a mean age of 9.4±6.3 (SD) years (range, 6 days-15 years) were included. Fifty-nine calcifications and 31 hemorrhages were detected. Sensitivities and specificities of the two magnetic resonance (MR) imaging techniques were calculated and compared using McNemar test. RESULTS QSM had a sensitivity of 84.7% and specificity of 100% for the detection of calcification. SWI phase images had a sensitivity of 49.1% and specificity of 100%. For the detection of hemorrhage, QSM had a sensitivity of 90.3% and a specificity of 98.3% whereas SWI phase images yielded a sensitivity of 64.5% and specificity of 96.6%. Overall, QSM displayed significantly better sensitivity than SWI phase images in identification of calcification and hemorrhage (P<0.05). CONCLUSION QSM is more reliable than SWI phase images in the identification of intracranial calcification and hemorrhage in pediatric patients using MR imaging.

Brain diffusion tensor imaging in children with tuberous sclerosis

PURPOSE To evaluate diffusion characteristics of tubers and white matter lesions in children with tuberous sclerosis (TS) using diffusion tensor imaging (DTI). MATERIALS AND METHODS Eighteen children (11 male, 7 female; mean age 9.3years, age range 1-16years) with a definite diagnosis of TS were recruited in this study. Apparent diffusion coefficient (ADC), fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) values in 89 tubers and 37 white matter lesions were measured and compared with those of contralateral normal regions. RESULTS ADC, AD, and RD values were significantly higher and FA values were lower in lesions, than the ones measured in contralateral normal regions for tubers (P<0.001). Similarly RD values were significantly higher and FA values were lower in white matter lesions (P<0.05). ADC and AD measures were detected to increase in white matter lesions, however no statistically significant difference was observed. The increase in the mean values of RD was significantly greater than the increase in the AD values for tubers and white matter lesions (P<0.05). CONCLUSION DTI can provide valuable information about the cytoarchitectural changes in TS lesions beyond morphologic MRI findings alone.

Magnetic Susceptibility Changes in the Basal Ganglia and Brain Stem of Patients with Wilson’s Disease: Evaluation with Quantitative Susceptibility Mapping

Objectives: Wilson’s disease (WD) is characterized with the accumulation of copper in the liver and brain. The objective of this study is to quantitatively measure the susceptibility changes of basal ganglia and brain stem of pediatric patients with neurological WD using quantitative susceptibility mapping (QSM) in comparison to healthy controls. Methods: Eleven patients with neurological WD (mean age 15 ± 3.3 years, range 10–22 years) and 14 age-matched controls were prospectively recruited. Both groups were scanned on a 1.5 Tesla clinical scanner. In addition to T1- and T2-weighted MR images, a 3D multi-echo spoiled gradient echo (GRE) sequence was acquired and QSM images were derived offline. The quantitative measurement of susceptibility of corpus striatum, thalamus of each hemisphere, midbrain, and pons were assessed with the region of interest analysis on the QSM images. The susceptibility values for the patient and control groups were compared using two-sample t-test. Results: One patient with WD had T1 shortening in the bilateral globus pallidus. Another one had hyperintensity in the bilateral putamen, caudate nuclei, and substantia nigra on T2-weighted images. The rest of the patients with WD and all subjects of the control group had no signal abnormalities on conventional MR images. The susceptibility measures of right side of globus pallidus, putamen, thalamus, midbrain, and entire pons were significantly different in patients compared to controls (P < 0.05). Conclusion: QSM method exhibits increased susceptibility differences of basal ganglia and brain stem in patients with WD that have neurologic impairment even if no signal alteration is detected on T1- and T2-weighted MR images.

Percutaneous management of benign biliary disorders in children

PURPOSE The goal of this study was to analyze the outcomes of percutaneous transhepatic management of benign biliary disorders in pediatric patients. MATERIALS AND METHODS This study included 11 pediatric patients who underwent percutaneous transhepatic biliary interventional procedures between September 2007 and December 2016. There were 3 males and 8 females with a mean age of 9.6±5.4 (SD)years (range: 2-17years). Technical details, complications and outcome of the procedures were evaluated. RESULTS The underlying pathologies were bile duct stones (n=2), bile leakage (n=4), choledochal cyst (n=3) and benign biliary stricture (n=2). The therapeutic interventional procedures were as follows; percutaneous stone removal in patients with bile duct stones, external biliary drainage in patients with choledochal cyst, bile diversion by internal-external percutaneous biliary drainage (IE-PBD) in patients with bile leakage, plastic stent placement, IE-PBD with balloon dilatation in patients with benign biliary stricture. The procedures were successful in all patients technically and clinically. One patient experienced intermittent fever. CONCLUSION Percutaneous transhepatic biliary interventional procedure is an effective and safe approach for the treatment of pediatric patients with bile duct stones, bile leakage, symptomatic choledochal cyst and benign biliary stricture when endoscopic procedure is unavailable or fails.

Lung magnetic resonance imaging for pneumonia in children

Technical factors have historically limited the role of MRI in the evaluation of pneumonia in children in routine clinical practice. As imaging technology has advanced, recent studies utilizing practical MR imaging protocols have shown MRI to be an accurate potential alternative to CT for the evaluation of pneumonia and its complications. This article provides up-to-date MR imaging techniques that can be implemented in most radiology departments to evaluate pneumonia in children. Imaging findings in pneumonia on MRI are also reviewed. In addition, the current literature describing the diagnostic performance of MRI for pneumonia is discussed. Furthermore, potential risks and limitations of MRI for the evaluation of pneumonia in children are described.