"Silent" kidney stones in "asymptomatic" primary hyperparathyroidism-a comparison of multidetector computed tomography and ultrasound.

PURPOSE: The purpose of this study was to demonstrate the high number of kidney stones in primary hyperparathyroidism (PHPT) and the low number of in fact "asymptomatic" patients. METHODS: Forty patients with PHPT (28 female, 12 male; median age 58 (range 33-80) years; interquartile range 17 years [51-68]) without known symptoms of kidney stones prospectively underwent multidetector computed tomography (MDCT) and ultrasound (US) examinations of the urinary tract prior to parathyroid surgery. Images were evaluated for the presence and absence of stones, as well as for the number of stones and sizes in the long axis. The MDCT and US examinations were interpreted by two experienced radiologists who were blinded to all clinical and biochemical data. Statistical analysis was performed using the Wilcoxon signed-rank test. RESULTS: US revealed a total of 4 kidney stones in 4 (10 %) of 40 patients (median size 6.5 mm, interquartile range 11.5 mm). MDCT showed a total of 41 stones (median size was 3 mm, interquartile range 2.25 mm) in 15 (38 %) of 40 patients. The number of kidney stones detected with MDCT was significantly higher compared to US (p = 0.00124). CONCLUSIONS: MDCT is a highly sensitive method for the detection of "silent" kidney stones in patients with PHPT. By widely applying this method, the number of asymptomatic courses of PHPT may be substantially reduced. MDCT should be used primarily to detect kidney stones in PHPT and to exclude asymptomatic PHPT.

A Th17- and Th2-skewed cytokine profile in cystic fibrosis lungs represents a potential risk factor for Pseudomonas aeruginosa infection.

RATIONALE: Cystic fibrosis (CF) is characterized by progressive pulmonary inflammation that is infection-triggered. Pseudomonas aeruginosa represents a risk factor for deterioration of lung function and reduced life expectancy. OBJECTIVES: To assess T-cell cytokine/chemokine production in clinically stable children with CF and evaluate the association between T-cell subtypes and susceptibility for infection with P. aeruginosa. METHODS: T-cell cytokine/chemokine profiles were measured in bronchoalveolar lavage fluid (BALF) from children with CF (n = 57; 6.1 ± 5.9 yr) and non-CF control subjects (n = 18; 5.9 ± 4.3 yr). Memory responses to Aspergillus fumigatus and P. aeruginosa were monitored. High-resolution computed tomography-based Helbich score was assessed. In a prospective observational trial the association between BALF cytokine/chemokine profiles and subsequent infection with P. aeruginosa was studied. MEASUREMENTS AND MAIN RESULTS: Th1- (INF-γ), Th2- (IL-5, IL-13), Th17- (IL-17A), and Th17-related cytokines (IL-1ß, IL-6) were significantly up-regulated in airways of patients with CF. IL-17A, IL-13, and IL-5 were significantly higher in BALF of symptomatic as compared with clinically asymptomatic patients with CF. IL-17A and IL-5 correlated with the percentage of neutrophils in BALF (r = 0.41, P < 0.05 and r = 0.46, P < 0.05, respectively). Th17- (IL-17A, IL-6, IL-1ß, IL-8) and Th2-associated cytokines and chemokines (IL-5, IL-13, TARC/CCL17), but not IFN-γ levels, significantly correlated with high-resolution computed tomography changes (Helbich score; P < 0.05). P. aeruginosa- and A. fumigatus-specific T cells from patients with CF displayed significantly higher IL-5 and IL-17A mRNA expression. IL-17A and TARC/CCL17 were significantly augmented in patients that developed P. aeruginosa infection within 24 months. CONCLUSIONS: We propose a role for Th17 and Th2 T cells in chronic inflammation in lungs of patients with CF. High concentrations of these cytokines/chemokines in CF airways precede infection with P. aeruginosa.

Targeting CD20 in melanoma patients at high risk of disease recurrence.

Melanomas contain distinct cell subpopulations. Several of these subpopulations, including one expressing CD20, may harbor stem cell-like or tumor-initiating characteristics. We hypothesized that patients at high risk of disease recurrence could benefit from an adjuvant anti-CD20 therapy. Therefore, we initiated a small pilot trial to study the effect of the anti-CD20 antibody rituximab in a group of melanoma patients with stage IV metastatic disease who had been rendered without evident disease by way of surgery, chemotherapy and/or radiation therapy. The major objective was safety, while secondary objectives were description of recurrence-free intervals (RFI) and overall survival (OS). Nine patients received rituximab at 375 mg/m(2) qw for 4 weeks followed by a maintenance therapy every 8 weeks. Treatment was discontinued after 2 years or with disease recurrence. Treatment was well tolerated. After a median observation of 42 months, the median neither of RFI nor of OS has been reached. Despite therapy that ended after 2 years, six out of nine patients are still alive and five of them are recurrence-free. Though the patient number is too small for definitive conclusions, our data may represent a first example of the potential therapeutic value of targeting CD20(+) cell populations-at least for a subset of patients.

MR imaging of the gastro-intestinal tract in children.

MR imaging (MRI) is an established method for the evaluation of particularly inflammatory bowel disease in adults, as well as for acute abdominal pain in pregnant women. Despite the fact that MRI is ideally suited for the evaluation of children the method is still not established in these patients. The value of MRI in Crohn's disease, ulcerative colitis and appendicitis as well as intestinal tumors and malformations has been documented in children. There will be more indications in the future depending on the development of new imaging techniques, faster sequences, stronger gradients and increasing availability. Furthermore, the radiologist's attention must be drawn to decrease the radiation burden in children and to replace ionizing techniques especially in chronic disease with the need for repeated follow-up studies and in younger children. This review will discuss some general considerations for the use of MRI in evaluating the paediatric gastro-intestinal tract.

Fetal MRI of the urinary system.

The assessment of the urinary system is typically performed by ultrasound. Nevertheless, an ultrasound may be inconclusive in fetuses with renal diseases that result in anhydramnios or oligohydramnios. In such cases, and in other cases in which ultrasound is limited, further investigation with MR should be considered. In the following article, we will provide an overview of the most commonly encountered disorders of the urinary system and their appearance on fetal MR imaging. Fetal MR imaging can accurately diagnose a wide variety of urinary tract disorders and must be seen as a valuable complementary tool to ultrasound in the assessment of the urinary system, particularly in cases of inconclusive ultrasound findings.

Normal renal development investigated with fetal MRI.

OBJECTIVE: To evaluate age-dependent changes in fetal kidney measurements with MRI. PATIENTS AND METHODS: Fetal MRI examinations were used to study the kidney length (218 fetuses), signal intensities of renal tissue, renal pelvis, and liver tissue on T2-weighted images (223 fetuses), and the whole-kidney apparent diffusion coefficient (107 fetuses). A 1.5 T superconducting unit with a phased array coil was used in patients from 16 to 39 weeks' gestation. The imaging protocol included T2-weighted single-shot fast spin-echo, T2-weighted balanced angiography and diffusion-weighted sequences. Slice thickness ranged from 3 to 5mm. RESULTS: Fetal kidney length as a function of gestational age was expressed by the linear regression: kidney length (mm)=0.190 x gestational age (d) -8.034 (R(2) = 0.883, p < 0.001). Paired t-test analysis showed a highly statistically significant difference between the ratio of renal tissue signal intensity to renal pelvis signal intensity and the ratio of liver signal intensity to renal pelvis signal intensity on T2-weighted images (t = -50.963, d.f. = 162, p < 0.001), with renal tissue hyperintense to liver tissue. The apparent diffusion coefficient in relation to gestational age was described by the equation: ADC (microm(2)/s) = 0.0302 x square (gestational age (d)) -14.202 x gestational age (d) +2,728.6 (R(2) = 0.225, p < 0.001). CONCLUSION: The length, signal intensity on T2-weighted images, and apparent diffusion coefficient of the fetal kidney change significantly with gestational age. The presented data may help in the prenatal diagnosis of renal anomalies.

Cystic echinococcosis of the thyroid gland in children and adults.

In humans, cystic echinococcosis is one of the most serious helminthic diseases worldwide. The larval stages (cysts) of Echinococcus granulosus are mainly located in the liver and the lung. Other locations of infection are rare, which may occasionally hinder its diagnosis. A 14-year-old girl from Kosovo presented with a cystic lesion in the left thyroid lobe of 4 years duration. Although two percutaneous punctures had been performed, she developed a recurrence and therefore had to undergo thyroid surgery. The results of the histopathologic examination revealed a hydatid cyst, and consequently, the patient received a long-term course of medication, namely, albendazole. Imaging of the cranium and chest were normal. A computed tomography of the abdomen detected a further cyst in the liver which did not show the typical signs of cystic echinococcosis. An echinococcus cyst in the thyroid gland is rare, especially in children. In a review of the literature published since 1965, only 12 children have been reported. Although by definition percutaneous drainage is contraindicated to avoid the spread of protoscolices, it is documented in eleven patients without complications. Surgical extirpation is mandatory. Chemotherapy with benzomidazole derivatives is necessary to avoid recurrence.

Correlative high-resolution MR-anatomic study of sciatic, ulnar, and proper palmar digital nerve.

Aim of this study was o evaluate the effectiveness of high-resolution MR imaging in demonstrating the anatomic structure of peripheral nerves of different diameter and composition. The dissected sciatic, ulnar, and proper palmar digital nerve of fresh cadavers were imaged at pre-selected landmarks on a 3T MR scanner. The nerves were then embedded in formalin, sliced, stained, and microscopically analyzed. The size, shape, and signal intensity of the sheath and axonal structures in the nerves at the landmarks were identified in MR images by comparison with histologic sections. The fascicles were clearly distinguished and counted in all specimens with MR imaging and showed only small differences from the histologic evaluation. High resolution MR imaging has the potential to visualize the fascicular structure in nerves of all sizes, which may be helpful in the preoperative assessment.

Longitudinal observation of antenatally detected congenital lung malformations (CLM): natural history, clinical outcome and long-term follow-up.

OBJECTIVE: The objective of the study is to present longitudinal observations in antenatally detected congenital lung malformations (CLM), particularly pulmonary sequestration (PS) and cystic adenomatoid malformation (CAM). METHODS: Fetuses found to have a CLM on prenatal ultrasound (US) were included in this study and followed up until delivery. In all newborns radiographs and computerized tomography (CT) studies of the thorax were performed. Surgical procedures included sequesterectomy, lobectomy, segmentectomy, and non-anatomic resection. Based on prenatal US findings, intrauterine course, postpartum chest radiographs and CT scans, as well as clinical signs and surgical findings patients were divided into six groups. RESULTS: Over a period of 6 years, routine prenatal US revealed suggestion of CLM in a series of 35 consecutive fetuses. In six cases pregnancy was terminated or the fetuses suffered fetal demise. Another four fetuses became symptomatic in utero when sequential scanning revealed hydrops, hydrothorax, and enlargement of cysts or polyhydramnios. Three cases in this group received serial therapeutic amniocentesis and serial puncture of either the hydrothorax or intrapulmonary cysts. After postpartum treatment in the intensive care unit surgical procedures were performed uneventfully and confirmed the diagnosis of CAM, PS or hybrid type lesions. In 11 patients US findings were considered to demonstrate spontaneous resolution of the lesion, but disappearance without sequelae could be confirmed only in six infants. Five infants were shown to have persistent CLM on postpartum CT scans. These infants underwent resection of the lesion within the first year of life. In 11 fetuses CLM were continuously demonstrated during pregnancy with only slight changes in size and structure. Postpartum the infants were asymptomatic and were subjected to a systematic plan of diagnostic work-up and treatment. Surgery in these infants revealed a large number of hybrid type lesions (n=5). In three infants, the primary diagnosis of PS or CAM had to be corrected during the diagnostic and therapeutic work-up. CONCLUSION: CLM are diagnosed antenatally with an increasing frequency and are shown to be quite different from previously applied concepts. The expected clinical outcome is far better than thought to be possible.

First experiences with multidetector CT in traumatized children.

INTRODUCTION: The aim of this study was to describe and discuss first experiences with multidetector CT (MDCT) in the assessment of traumatized children. MATERIAL AND METHODS: Since the implementation of a MDCT scanner in April 2002, 85 children (31 girls, 54 boys with a mean age of 9.2 years) consecutively underwent MDCT (Siemens, Erlangen, Germany) with different protocols depending on age, weight, trauma mechanism and clinical presentation. In all patients in whom pathology was suspected, multiplanar reformations (MPR) in coronal and or sagittal orientation was performed. Examinations were evaluated by two radiologists retrospectively and in consensus. RESULTS: In 55 (65%) children, a MDCT solely of the head was performed, in 46 there was no pathology found. In six (7%), head and facial bones were scanned. Head and abdomen was examined in two (2%), in two (2%) the abdomen only and in one (1%) the pelvis solely. Scans of the spine were obtained in seven (8%) children. A thorax and abdomen examination only was obtained in one (1%) child each. In 11 (13%) children, a polytrauma protocol was performed. In all patients, the time of examination did not exceed 17 min, including setup time. All children survived at the writing of this report. CONCLUSION: MDCT was promising in the management of traumatized children and seems to shorten the necessary time to reach diagnosis and to initiate life-saving treatment.

Three-dimensional volume rendering of multidetector-row CT data: applicable for emergency radiology.

Multidetector-row computed tomography (MD-CT) not only creates new opportunities but also challenges for medical imaging. Isotropic imaging allows in-depth views into anatomy and disease but the concomitant dramatic increase of image data requires new approaches to visualize, analyze and store CT data. The common diagnostic reviewing process slice by slice becomes more and more time consuming as the number of slice increases, while on the other hand CT volume data sets could be used for three-dimensional visualization. These techniques allow for comprehensive interpretation of extent of fracture, amount of dislocation and fragmentation in a three-dimensional highly detailed setting. Further more, using minimal invasive techniques like CT angiography, new opportunities for fast emergency room patient's work up arise. But the most common application is still trauma of the musculoskeletal system as well as face and head. The following is a brief review of recent literature on volume rendering technique and some exemplary applications for the emergency room.

[Imaging of diseases of the thyroid gland in Austria]. / Bildgebende Diagnostik von Schilddrüsenerkrankungen in Osterreich.

Imaging techniques for first line investigation of diseases of the thyroid gland are sonography (US) and scintigraphy, followed in dedicated cases by magnetic resonance imaging (MRI). Malignant lesions are generally hypoechoic on US with calcifications visible in some cases. The appearance of lymph node metastases is similar to that of the primary tumour. The various forms of goiter are the most commonly occurring forms of thyroid diseases in Austria, they appear heterogenous with hyperechoic as well as hypoechoic or anechoic nodes, in some cases with calcification. US findings of thyreoiditis are in acute forms of the disease more hypoechoic with diffuse swelling and hyperechoic with scar formations in chronic forms. Ectopic thyroid tissue occurs often in the form of thyroglossal duct cysts which are anechoic or hypoechoic.

[Imaging of the parathyroid gland]. / Bildgebende Diagnostik der Nebenschilddrüsen.

Diseases of the parathyroid gland are rare and are especially in case of hyperparathyroidism associated with hyperacalcaemia. Enlarged glands are, therefore, generally not detected with imaging modalities. The aim of imaging studies is to locialize abnormal glands. Ultrasound is the modality of choice for the primary investigation followed by nuclear medicine studies. Computed tomography or angiography with vein sampling should only be performed if the results of other investigations are equivocal. Magnetic resonance imaging is performed rarely in Austria with its high prevalence of endemic goiter.

Results of a quality assurance review of external beam radiation therapy in the International Society of Paediatric Oncology (Europe) Neuroblastoma Group's High-risk Neuroblastoma Trial: a SIOPEN study.

PURPOSE: Radiation therapy is important for local control in neuroblastoma. This study reviewed the compliance of plans with the radiation therapy guidelines of the International Society of Paediatric Oncology (Europe) Neuroblastoma Group (SIOPEN) High-Risk Trial protocol. METHODS AND MATERIALS: The SIOPEN trial central electronic database has sections to record diagnostic imaging and radiation therapy planning data. Individual centers may upload data remotely, but not all centers involved in the trial chose to use this system. A quality scoring system was devised based on how well the radiation therapy plan matched the protocol guidelines, to what extent deviations were justified, and whether adverse effects may result. Central review of radiation therapy planning was undertaken retrospectively in 100 patients for whom complete diagnostic and treatment sets were available. Data were reviewed and compared against protocol guidelines by an international team of radiation oncologists and radiologists. For each patient in the sample, the central review team assigned a quality assurance score. RESULTS: It was found that in 48% of patients there was full compliance with protocol requirements. In 29%, there were deviations for justifiable reasons with no likely long-term adverse effects resulting. In 5%, deviations had occurred for justifiable reasons, but that might result in adverse effects. In 1%, there was a deviation with no discernible justification, which would not lead to long-term adverse events. In 17%, unjustified deviations were noted, with a risk of an adverse outcome resulting. CONCLUSIONS: Owing to concern over the proportion of patients in whom unjustified deviations were observed, a protocol amendment has been issued. This offers the opportunity for central review of radiation therapy plans before the start of treatment and the treating clinician a chance to modify plans.

Diffusion-weighted MR imaging of the normal fetal lung.

To quantify apparent diffusion coefficient (ADC) changes in fetuses with normal lungs and to determine whether ADC can be used in the assessment of fetal lung development. In 53 pregnancies (20-37th weeks of gestation), we measured ADC on diffusion-weighted imaging (DWI) in the apical, middle, and basal thirds of the right lung. ADCs were correlated with gestational age. Differences between the ADCs were assessed. Fetal lung volumes were measured on T2-weighted sequences and correlated with ADCs and with age. ADCs were 2.13 +/- 0.44 microm(2)/ms (mean +/- SD) in the apex, 1.99 +/- 0.42 microm(2)/ms (mean +/- SD) in the middle third, and 1.91 +/- 0.41 microm(2)/ms (mean +/- SD) in the lung base. Neither the individual ADC values nor average ADC values showed a significant correlation with gestational age or with lung volumes. Average ADCs decreased significantly from the lung apex toward the base. Individual ADCs showed little absolute change and heterogeneity. Lung volumes increased significantly during gestation. We have not been able to identify a pattern of changes in the ADC values that correlate with lung maturation. Furthermore, the individual, gravity-related ADC changes are subject to substantial variability and show nonuniform behavior. ADC can therefore not be used as an indicator of lung maturity.

MRI investigation of normal fetal lung maturation using signal intensities on different imaging sequences.

To purpose of this paper is to study the relation between normal lung maturation signal and changes in intensity ratios (SIR) and to determine which magnetic resonance imaging sequence provides the strongest correlation of normal lung SIs with gestational age. 126 normal singleton pregnancies (20-37 weeks) were examined with a 1.5 Tesla unit. Mean SIs for lungs, liver, and gastric fluid were assessed on six different sequences, and SIRs of lung/liver (LLSIR) and lung/gastric fluid (LGSIR) were correlated with gestational age for each sequence. To evaluate the feasibility of SIRs in the prediction of the state of the lung maturity, accuracy of the predicted SIRs (D*) was measured by calculating relative residuals (D*-D)/D for each sequence. LLSIRs showed significant changes in every sequence (p<0.05), while LGSIRs only on two sequences. Significant differences were shown for the mean of absolute residuals for both LLSIRs (p<0.001) and for LGSIRs (p=0.003). Relative residuals of LLSIRs were significantly smaller on T1-weighted sequence, whereas they were significantly higher for LGSIRs on FLAIR sequence. Fetal liver seems to be adequate reference for the investigation of lung maturation. T1-weighted sequence was the most accurate for the measurement of the lung SIs; thus, we propose to determine LLSIR on T1-weighted sequence when evaluating lung development.

In vitro study of ingested coins: leave them or retrieve them?

BACKGROUND: Objects and notably coins are frequently swallowed by children 3 to 5 years old. Precisely how they should be managed after passing the gastroesophageal junction without causing symptoms remains controversial. This study was performed to assess dissolution of specific metals from coins immersed in simulated gastric juice. METHODS: Four types of euro and US coins were immersed in simulated gastric juice for 4, 24, 72, and 120 hours. Six metals were evaluated by inductively coupled plasma-atomic emission spectrometry. Weight loss and corrosive behavior were also determined. RESULTS: After only 4 hours, metals had dissolved from euro (Cu, 2.86-7.85 mg; Ni, 0.23-0.52 mg; Zn, 0.09-0.99 mg; Al, 0.24 mg; Sn, 0.02 mg) and US (Cu, 1.45-6.65 mg; Ni, 0-0.62 mg; Zn, 0-0.14 mg) coins. Their concentrations in simulated gastric juice peaked after 24 to 72 hours (milligrams/hours) in euro (Cu, 218/48; Ni, 82.50/72; Zn, 83.00/72; Al, 14.65/72; Sn, 0.66/72) and US (Cu, 126.50/24; Ni, 88.00/72; Zn, 149.00/24) coins. All coins underwent corrosion and weight loss (by 2.56%-4.8%). CONCLUSIONS: Coins retained in the stomach will release a number of heavy metals well known to cause dose-dependent poisoning. Studies to evaluate their toxicity and absorption are needed to optimize treatment.

Imaging of the scrotum in children.

Clinical examination of the scrotum is difficult due to the small size of the testes and the epididymis in infants and young children, and eliciting patients' history is challenging. Therefore imaging of the scrotum in childhood bears great importance. Ultrasound is the standard imaging technique of choice providing the clinicians with a definitive diagnosis in most cases. However, in conditions of testicular torsion and epididymoorchitis--the most common differential diagnosis of scrotal pain--ultrasound findings can be inconclusive and further evaluation is required. Since there is a large overlap between paediatric and adult pathology, differences from adults in anatomy and pathology must be considered when evaluating the paediatric scrotum.

Ultrasound of the appendix in children: is the child too obese?

The negative influence of obesity on the detection rate of the appendix for US in adults has been reported. It has been assumed that obesity is a limiting factor in the detection of the appendix with US in children as well, but this has not yet been proven. The aim of our study was to evaluate whether nutritional condition (defined by the body mass index-for-age percentiles: BMI-FAP) influences the detection of the appendix in children on US. One hundred twenty-six children (65 girls and 61 boys) with a mean age of 11.4 years with clinically suspected acute appendicitis underwent ultrasound on a commercially available high-end machine (HDI 5000, ATL, Bothell, Wash.). The BMI was calculated, and children were divided in three weight groups in accordance with the BMI-FAP, and were correlated with US findings. Evaluation of the three weight groups in accordance with the BMI-FAP demonstrated significant differences ( p=0.04) in the detection of the appendix. There was no statistical significance for the BMI, weight, height, and age solely for the detection of the appendix. In children there is a correlation between the nutritional condition as defined by the BMI-FAP and the detection of the appendix.

US as a primary diagnostic tool in relation to negative appendectomy: six years experience.

PURPOSE: To evaluate the effect of ultrasonography (US) on the rate of appendectomy after false-positive diagnosis of acute appendicitis (negative appendectomy). MATERIALS AND METHODS: Data were analyzed in 736 pediatric patients (mean age, 13.2 years) who had undergone appendectomy between 1995 and 2000. Histologic data were compared in patients who underwent US with those who did not undergo imaging prior to surgery. US was performed by a radiologist or a pediatric surgeon or both. RESULTS: A total of 643 (87.4%) of the 736 pediatric patients underwent preoperative US, and 93 (12.6%) of the 736 did not undergo preoperative US. Of the 736 patients, 97 (13.2%) underwent negative appendectomy. Thirty-four (36.6%) of the 93 patients who underwent appendectomy with no preoperative US and 63 (9.8%) of the 643 patients who underwent preoperative US underwent negative appendectomy. There was a significant association between US and positive appendectomy (P <.001). CONCLUSION: US in pediatric patients suspected of having appendicitis can significantly lower the negative appendectomy rate.