Patient doses in paediatric CT: feasibility of setting diagnostic reference levels.

Despite the fact that doses to paediatric patients from computed tomography (CT) examinations are of special concern, only few data or studies for setting of paediatric diagnostic reference levels (DRLs) have been published. In this study, doses to children were estimated from chest and head CT, in order to study the feasibility of DRLs for these examinations. It is shown that for the DRLs, patient dose data from different CT scanners should be collected in age or weight groups, possibly for different indications. For practical reasons, the DRLs for paediatric chest CT should be given as a continuous DRL curve as a function of patient weight. For paediatric head CT, DRLs for a few age groups could be given. The users of the DRLs should be aware of the calibration phantom applied in the console calibration for different paediatric scanning protocols. The feasibility of DRLs should be re-evaluated every 2-3 y.

Risk factors for physical child abuse in infants and toddlers.

BACKGROUND: We examined the risk factors and injuries in physical child abuse between November 2003 and February 2007. PATIENTS AND METHODS: The uptake area of the University Hospital of Turku, Finland, consists of about 700 000 inhabitants. Forty-eight cases of physical child abuse were examined. The median age of the abused children was 2.2 years, for children with skull fractures it was 0.5 years. The incidence of child physical abuse increased during the study period; it was 0.6/month in 2004 and 1.7/month in 2006. Mortality in the study group was 2.1 %. RESULTS: Depression, overactivity, crying and prematurity were risk factors in the physically abused children. Parental risk factors were alcohol and drug abuse. Most often the perpetrator was the father or stepfather; when the perpetrator was unknown, the children were mostly in their mothers' care. The average delay of 3 weeks until starting the investigation into abuse was mostly due to delays by health centers or homes. Radiographs were the cornerstones of the medical examination but magnetic resonance examinations were essential for the examination protocol. CONCLUSIONS: All levels of public health services, day care facilities and schools must be aware of possible physical child abuse and initiate an investigation as soon as possible by contacting the authorities. Physically abused children and their families must be followed up and supported for a sufficiently long period by social pediatric outpatient wards. The general information on child maltreatment provided to the public needs to be increased to prevent abuse. A child welfare report must be made to social workers in every maltreatment case examined in hospital, and in most cases the offence must also be reported to the police. Nevertheless, in certain cases even permanent custody of the child cannot be avoided.

Magnetic resonance imaging in pediatric elbow fractures.

PURPOSE: Magnetic resonance imaging (MRI) evaluation of pediatric elbow trauma with or without a visible fracture on radiography. MATERIAL AND METHODS: MRI was performed in the acute phase in 25 children with an elbow injury. Nine patients with an elbow effusion only on radiographs and 16 with a fracture or luxation seen on radiographs underwent subsequent MRI. No sedation was used. RESULTS: MRI revealed eight occult fractures (89%) in seven out of nine patients who had only an effusion on radiographs. Based on MRI findings, septic arthritis was suspected in one patient. Two patients out of five with a supracondylar fracture on the radiograph had a cartilage lesion in the humerus. MRI depicted a 3-mm gap on the articular surface in two patients with a lateral condyle fracture, a more accurate fracture location in two patients than the radiographs, and an additional occult fracture in two patients. MRI showed a fracture not seen on radiographs in two of three patients with prior luxation. CONCLUSION: MRI is a sensitive and accurate method in the diagnosis of pediatric elbow injuries, especially when only an effusion is present on radiographs. Occult fractures are more common in pediatric patients with elbow injury than reported earlier.

Differentiation of bacterial and viral pneumonia in children.

BACKGROUND: A study was undertaken to investigate the differential diagnostic role of chest radiographic findings, total white blood cell count (WBC), erythrocyte sedimentation rate (ESR), and serum C reactive protein (CRP) in children with community acquired pneumonia of varying aetiology. METHODS: The study population consisted of 254 consecutive children admitted to hospital with community acquired pneumonia diagnosed between 1993 and 1995. WBC, ESR, and CRP levels were determined on admission. Seventeen infective agents (10 viruses and seven bacteria) were searched for. Chest radiographs were retrospectively and separately reviewed by three paediatric radiologists. RESULTS: A potential causative agent was found in 215 (85%) of the 254 cases. Bacterial infection was found in 71% of 137 children with alveolar infiltrates on the chest radiograph, while 72% of the 134 cases with a bacterial pneumonia had alveolar infiltrates. Half of the 77 children with solely interstitial infiltrates on the chest radiograph had evidence of bacterial infection. The proportion of patients with increased WBC or ESR did not differ between bacterial and viral pneumonias, but differences in the CRP levels of >40 mg/l, >80 mg/l, and >120 mg/l were significant although the sensitivity for detecting bacterial pneumonia was too low for use in clinical practice. CONCLUSIONS: Most children with alveolar pneumonia, especially those with lobar infiltrates, have laboratory evidence of a bacterial infection. Interstitial infiltrates are seen in both viral and bacterial pneumonias.

Pulmonary imaging and function in the common cold.

The common cold is generally considered to be an upper respiratory tract infection. We studied the lower respiratory tract in 76 otherwise healthy young adults with the common cold. Viral infection was diagnosed in 56 (74%) of the 76 subjects. Rhinovirus was detected in 42 (55%) subjects. Chest radiography (CR) and high-resolution computerized tomography (HRCT) were carried out in 40 subjects on day 7, and pulmonary function testing with bronchodilator challenge was carried out in 36 patients on days 7 and 21 of the study. Clinical examinations were carried out on days 1, 7 and 21. The subjects recorded their symptoms on a diary card for 20 d. The mean duration of cough was 8.4 (SD 6.5) d and that of sputum production 5.9 (SD 6.4) d. No abnormal findings were detected in the lungs on auscultation. CR and HRCT showed no pulmonary changes associated with the common cold. No clinically remarkable increases were seen in peak expiratory flow, forced expiration volume in 1 s or forced vital capacity after bronchodilator challenge on either days 7 or 21. All patients made a clinical recovery without antimicrobial therapy within 21 d. We conclude that the common cold in young otherwise healthy adults is an upper respiratory tract infection and that clinically important abnormalities in the lower respiratory tract are rare.

Physical activity and bone mineral acquisition in peripubertal girls.

The association of the amount and type of physical activity with bone mineral acquisition was studied in 191 peripubertal Caucasian girls aged 9-16 years (66 gymnasts, 65 runners, and 60 nonathletic controls). Weight, height, stage of puberty, the amount of leisure-time physical activity, and years of training were recorded, and dietary calcium and vitamin D were assessed by a semi-quantitative questionnaire. The bone area, the bone mineral density (BMD), and the bone mineral content (BMC) of the femoral neck, lumbar spine and antebrachium were measured by dual-energy x-ray absorptiometry. The unadjusted mean values of BMD at the femoral neck were 15.2% higher in the pubertal gymnasts than in the controls (P<0.001). Compared with the controls, the mean BMC adjusted for bone area of the pubertal gymnasts at the femoral neck and lumbar spine was 16.4% and 10.8% higher, respectively. When comparing the association of the type of physical activity among the pubertal athletics by multiple regression analysis, height, physical activity, gymnastics, and Tanner stage emerged as significant variables and accounted for 54.7% and 63.4% of the total variation in BMD of the femoral neck and lumbar spine, respectively. These results indicate that physical activity is associated with bone mineral acquisition in peripubertal girls and that high-impact weight-bearing exercise seems to be particularly associated with the increase of the BMD at the femoral neck.

Pulmonary abnormalities in patients with primary hypogammaglobulinemia.

BACKGROUND: Pulmonary complications are common in patients with primary hypogammaglobulinemia. Intravenous immunoglobulin replacement therapy has been thought to reduce the occurrence of pulmonary complications, yet they do occur. OBJECTIVE: The purpose of this study was to evaluate pulmonary abnormalities in 22 patients with primary hypogammaglobulinemia (18 with common variable immunodeficiency, 4 with X-linked agammaglobulinemia) and to conduct a prospective 3-year follow-up study to assess the possible progression of pulmonary abnormalities. METHODS: Pulmonary changes were evaluated with use of pulmonary imaging (chest radiographs, high-resolution computed tomography), and pulmonary function testing. RESULTS: High-resolution computed tomography revealed pulmonary abnormalities in 21 patients. Bronchiectasis was present in 16 patients, whereas chest radiographs revealed bronchiectasis in only 3 patients. Pulmonary function testing showed obstruction in 5 patients. A prospective 3-year follow-up was conducted in 14 patients. It showed silent progression of bronchiectasis in 5 of the 14 patients, all of whom were receiving intravenous immunoglobulin replacement therapy and had preinfusion serum IgG concentrations of 5 g/L or more. CONCLUSIONS: Pulmonary abnormalities develop in most patients with primary hypogammaglobulinemia. A new finding is that silent and asymptomatic progression of pulmonary changes may occur in patients despite an adequate immunoglobulin replacement therapy. High-resolution computed tomography is the method of choice in monitoring pulmonary changes.

Digital fluoroscopy before and after laser uvulopalatopharyngoplasty in obstructive sleep apnea. Importance of pharyngeal collapsibility and hyoid bone position.

PURPOSE: To study the changes in pharyngeal behavior after laser uvulopalatopharyhgoplasty (LUPPP). MATERIAL AND METHODS: The dynamic changes in the upper airway size were evaluated with digital fluoroscopy in 24 patients with obstructive sleep apnea (OSA) before and after LUPPP and in 16 normal controls, while they were awake and breathing normally. Cephalometric measurements were also made. The patients were classified into the categories of good and poor responders by means of a static-charge-sensitive bed. RESULTS: Following LUPPP, collapsibility at the velopharyngeal level was within the normal range m 15 of 17 good responders, but only in 2 of 7 poor responders (p = 0.0086). The minimum airway size at the same level showed a similar trend. In 3 of 7 poor responders the hyoid bone was positioned more caudally than in the good responders (p = 0.017). CONCLUSION: Digital fluoroscopy provides information on the change in upper airway behavior after LUPPP.

Upper airway size and collapsibility in snorers: evaluation with digital fluoroscopy.

This study addressed the question of whether there are any differences in the size and collapsibility of the upper airway measured by digital fluoroscopy, between snorers and controls whilst they were awake and breathing normally; and whether there are any correlations between these measurements and other clinical data. The dynamic changes of the upper airway size were evaluated using digital fluoroscopy in 33 patients and 16 normal controls. The measurements were compared with findings in an overnight sleep study, including a static-charge-sensitive bed (SCSB) and oximeter recordings. The minimum anteroposterior dimension at the velopharyngeal level was smaller in patients with partial upper airway obstruction than in controls (p<0.005); patients with complete obstruction did not differ from the controls. The velopharyngeal airways were also more collapsible in patients with severe partial obstruction (p<0.01) than in controls. At the oropharyngeal and hypopharyngeal levels, the dimensions and the collapsibilities were similar in patients and controls. The velopharyngeal collapsibility correlated with body mass index (p

Gallbladder hypocontractility in infantile colic.

We evaluated gallbladder contractility in 58 colicky infants and 57 age-matched controls. Gallbladder size was measured before and 1 h after feeding and the contraction index of the gallbladder was calculated. The results showed decreased contractility of the gallbladder in colicky infants: mean contraction index in colicky infants was 56% (95% confidence interval, 49-63%) and in controls 67% (61-73%). No difference was found in the fasting size of the gallbladder. Postprandial contraction was decreased in colicky infants examined in the evening (n = 14) compared with those examined in the morning (n = 44). Decreased contraction of the gallbladder was found in those colicky infants who presented colicky cry compared with colicky infants without symptoms at the time of examination. No structural abnormalities were found in the general abdominal survey. In conclusion, infants with colic have hypocontractility of the gallbladder. This indicates abnormal biliary tract physiology in association with infantile colic.

Compression sonography in the diagnosis of deep venous thrombosis of the leg.

The value of compression sonography was assessed to reduce the number of phlebographies otherwise necessary when deep venous thrombosis (DVT) is suspected among hospital patients. Compression sonography was used to study 119 prospective hospital patients who were suspected of having DVT of the lower extremity. The results were compared to those by phlebography. There were 44 DVTs detected by phlebography; ten of these were located only in the calf, below the knee. Of the remaining 34 femoropopliteal DVTs 33 were detected by the compression sonography technique. It is concluded that the use of compression sonography for primary investigation of suspected DVT reduces the number of patients who require phlebography to those whose results by compression sonography are negative. In our study, this would have represented a decrease of 28%, corresponding to a reduction of the total diagnostic costs by 10%.

Pulmonary manifestations in lysinuric protein intolerance.

STUDY OBJECTIVES: To evaluate the pulmonary manifestations and the course of acute respiratory insufficiency associated with lysinuric protein intolerance (LPI). DESIGN: Retrospective review of clinical data and chest radiographs (total 225) obtained during the lifetime follow-up of 31 LPI patients. About half of the 25 patients without respiratory symptoms underwent high-resolution computed tomography (HRCT) of the lungs, radionuclide perfusion imaging, whole body plethysmography, and diffusing capacity measurements. PATIENTS: Thirty-one Finnish patients with LPI. RESULTS: During the follow-up period, four children with LPI died in respiratory insufficiency, 1 adult had an episode of respiratory insufficiency, and another had chronic symptoms, whereas 25 patients remained symptom-free. The radiologic findings in acute progressive respiratory insufficiency were uniform: at first, reticulonodular interstitial densities and, later on, progressive airspace disease. At autopsy, three patients showed pulmonary alveolar proteinosis and one had pulmonary hemorrhage and cholesterol granulomas. One adult had reversible respiratory insufficiency with signs of bronchiolitis obliterans, another adult had recurrent episodes of chest pain, dyspnea, and hypoxia. Of the symptom-free patients, one third (8 of 25) had signs suggestive of pulmonary fibrosis evidenced on chest radiographs and two thirds (8 of 14) had signs evidenced by HRCT films. Most symptom-free patients showed mild abnormalities either in perfusion imaging (9 of 12) or in function tests (8 of 12). CONCLUSION: In childhood, patients with LPI are highly predisposed to develop pulmonary hemorrhages and alveolar proteinosis. Interstitial lung densities may precede the acute phase. Most adult LPI patients show radiologic signs of interstitial lung disease but only a few show clinical impairment.

Gall bladder contractility in preterm infants.

Postnatal response of the gall bladder to feeding was studied in 28 preterm infants (gestational age 24-37 weeks) by ultrasonography immediately before feeding and one hour after feeding. Nineteen of the infants were studied once during the first week of life, and nine infants were studied weekly from a postconceptional age of 27-31 until a postprandial gall bladder contraction was seen. A contraction index was calculated as a percentage decrement of the surface area of the gall bladder from its initial value. All preterm infants of more than 33 weeks' gestation showed a gall bladder response to feeding with a contraction index of at least 50%. Very preterm infants (gestational age 27-32 weeks) showed no postprandial gall bladder contraction or the contraction index was under 50%. In a follow up study of nine very preterm infants, the contraction index exceeded 50% at a postconceptional age of 29 to 32 weeks. One infant with prolonged feeding problems had no postprandial gall bladder response before the postconceptional age of 38 weeks. The contraction index increase was dependent on gestational age at birth and on the bolus volume of feeds.

Skeletal manifestations of lysinuric protein intolerance. A follow-up study of 29 patients.

Lysinuric protein intolerance (LPI) is an autosomal recessive disease caused by defective transport of the cationic amino acids lysine, arginine, and ornithine at the cell membrane. About 80 patients with LPI have been described worldwide, almost half of them in Finland. The symptoms appear in early childhood as a failure to thrive, growth retardation, muscular hypotonia, and episodes of stupor after protein-rich meals. Twenty-nine Finnish patients (current median age 24.8 years, range 3.7-47.9 years) over a mean follow-up time of 18.1 years (range 1.2-27.2 years) had 57 fractures after minor trauma, mostly in childhood. Their 440 skeletal radiographs showed severe osteoporosis (13/29), controversially abnormal thickening of cortex of the metacarpals (7/29), or thin cortices of the long bones (5/29), endplate impression of vertebrae (8/29), rickets-like metaphyses (2/29), or early destruction of cartilage (3/29). Skeletal maturation was delayed by 1-5 years in 23 of 24 patients. There was no correlation between fracture incidence, radiological bone structure, and delayed skeletal maturation.

High resolution CT of the lungs: Proper mA s settings for clinical use.

Fifty-five patients undergoing routine chest CT were examined with four additional high resolution computed tomography (HRCT) slices to determine the proper milliampere-second settings for clinical HRCT of the lungs. The following technical factors were used: 1-mm collimation, 2-s scan time, 120 kVp and different milliampere settings (160 mA, 100 mA, 60 mA, 30 mA). On 47 out of 54 patients all the four HRCT cuts were at exactly the same level. These images were independently reviewed and assessed by three radiologists. The body mass index was calculated in order to determine the effect of the size of the patient on the milliamperage setting needed. The standard deviation of CT values of 1 mm and 10 mm slice was measured in a Plexiglas phantom with different mA settings. The slice thickness was measured with thermoluminescence dosimeter. In the phantom study the change of milliamperage from 160 mA to 30 mA at 120 kVp and 2 s increased standard deviation in CT units from about 4.6 to 8.9 in 1 mm slice and from about 2.9 to 4.3 in 10 mm slice. The Computed Tomography Dose Index (CTDI) values of both 1 mm and 10 mm slices at 160 mA-30 mA were approximately from 9 to 2 cGy (rad). In the patient study 1 mm HRCT scans with 120 kVp/100 mA/2 s showed the same diagnostic information as 120 kVp/160 mA/2 s scans for all patients regardless of size. If only the normal weight patients are considered, all the details were also well seen with 120 kVp/60 mA/2 s settings. In our study contrary to earlier reports 30 mA/2s was inadequate for diagnosis. We conclude that at 120 kVp medium-dose settings 60-100 mA/2 s or 120-200 mA s are in clinical practice appropriate for HRCT studies of the lungs in most patients.

Information compression in dynamic radiological studies.

The large volumes of digital image data from radiological examinations demand further research and practical solutions in image compression before PACS solutions in large radiological departments are plausible. But another type of compression of image information is also possible, which has, in fact, been somewhat utilized already in analog form, but which has far better possibilities in the digital world. The number of essential images in dynamic X-ray, nuclear medicine, examinations etc. can be greatly reduced. These examinations producing image series are reviewed in terms of compression of information. 3-D displays are very useful in slice imaging, because they provide a means to see easier inside the human body than a number of slice images side by side. We also provide a new method, dynamic pulmonary imaging with digital fluoroscopy, as an example of the digital possibilities to compress a number of images into parametric images, numbers, histograms and curves. These processes also have other positive consequences information is transformed into a more easily perceptible form.

Dynamic pulmonary imaging: performance properties of a digital fluoroscopy system.

The physical characteristics of dynamic pulmonary imaging with digital fluoroscopy, which differ from those in DSA equipment, have been determined. The spectral distributions and mean energies were calculated and corresponding exposures with varying high voltage and copper filtration (60-100 kVp, 0-2.83 mm Cu) were measured. The utilization of 90-100 kVp with a filter consisting of 1.39 mm Cu and 3 mm Al minimized disturbing skeletal artifacts and reduced the radiation exposure by a factor of approximately 5 in comparison with imaging at 60 kVp without copper filtration. Simultaneously, the measured signal decreased by about 25%. The mean energy of this spectrum exceeded that of 140 kVp chest imaging. The dynamic pulmonary imaging method produces logarithmically transformed x-ray transmittance values linearly related (r = -0.999) to water thickness between 7-10.5 cm, which is equivalent to the normal range of the chest in pediatric patients. A good linear correlation (r = 0.933,N = 92) was obtained when the change in transmitted radiation was compared with tidal volume measured in a rabbit model using a pneumotachometer. The results indicate that the method is applicable for quantitative measurements of pulmonary ventilation. Changes in tidal ventilation can be measured with this noninvasive x-ray imaging technique.

The size and contractility of the gallbladder in infants.

The size of the gallbladder and the common bile duct as well as the contractility of the gallbladder were measured in infants under the age of 1 year. A total of 43 healthy infants were studied at their routine visit to the well-baby clinic at the ages of 6 weeks, 4 months, 8 months or 12 months. Gallbladder size was measured before and after a test meal. Fasting gallbladder size increased with the age of the infants. However, when the size was corrected for the infant's weight, no age-related variation was found. The contraction index (CI) was determined as a percentage decrement of planimetric gallbladder size from the initial size. The mean CI declined with age from 75% (+/- 27%) (mean (+/- SD)) at the age of 6 weeks to 24% (+/- 28%) at the age of 12 months. Overall CI varied from -44% to 100%. An increase in gallbladder size after the test meal was observed in 4 infants. Gallbladder volumes were also calculated, but two-dimensional measurements were regarded as more accurate in infants. A large variation was found in the size as well as in the contractility of the gallbladder in infants less than 1 year of age.

Ultrasonic guidance of lumbar sympathetic and celiac plexus block: a new technique.

BACKGROUND AND OBJECTIVES: Lumbar sympathetic and celiac plexus block are widely used to treat chronic pain of diverse etiologies. To avoid complications and confirm the correct position of the needle, fluoroscopy and computed tomography have been used to follow the procedure visually. Our objective was to examine whether ultrasonography could be used instead of these techniques. METHODS: Forty-eight neurolytic sympathectomies were performed using ultrasonographic guidance. The results were evaluated clinically and by color-doppler technique as applicable. RESULTS: This new technique was shown to provide excellent results in ensuring the safe passage of the needle and documenting the correct spread of neurolytic agent (phenol-glycerol). The correct position of the needle was achieved on the first attempt in all cases. CONCLUSIONS: The benefits of this technique are that it is inexpensive, there is no radiation, and the anatomy involved can be thoroughly examined before and after the procedure. Phenolglycerol may be the best choice as the neurolytic agent because it provides excellent contrast.