Inter-rater reliability of the radiographic assessment of simple bone cysts

PURPOSE

To develop and evaluate the reliability of an explicit set of parameters and criteria for simple bone cysts (SBCs) and evaluate the reliability of single versus serial chronological reading methods.

METHODS

Radiographic criteria were developed based on the literature and expert consensus. A single anteroposterior/lateral radiograph from 32 subjects with SBC were evaluated by three radiologists. A second reading was then conducted using revised criteria including a visual schematic. In the third reading the same images were assessed but radiologists had access to images from two additional time points. Inter-rater reliability was assessed after each reading using kappa (κ) and percentage agreement for categorical and binary parameters and intra-class correlation coefficient (ICC) for continuous parameters.

RESULTS

Parameters that were revised with more explicit definitions including the visual schematic demonstrated consistent or improved inter-rater reliability with the exception of continuous cortical rim present and cyst location in the metaphysis and mid-diaphysis. Cortical rim displayed only slight reliability throughout (κ= -0.008 to 0.16). All other categorical parameters had a percentage agreement above 0.8 or a moderate (κ= 0.41 to 0.60), substantial (κ = 0.61 to 0.80) or almost perfect inter-rater reliability (κ = 0.81 to 1.0) in at least one reading. All continuous parameters demonstrated excellent inter-rater reliability (ICC > 0.75) in at least one reading with the exception of scalloping (ICC = 0.37 to 0.70). Inter-rater reliability values did not indicate an obviously superior method of assessment between single and serial chronological readings.

CONCLUSION

Explicit criteria for SBC parameters used in their assessment demonstrated improved and substantial inter-rater reliability. Inter-rater reliability did not differ between single and serial chronological readings.

LEVEL OF EVIDENCE

Not Applicable.

Magnetic resonance imaging and joint outcomes in boys with severe hemophilia A treated with tailored primary prophylaxis in Canada

BACKGROUND/OBJECTIVES

Tailored primary prophylaxis (TPP) is a reduced-intensity treatment program for hemophiliacs with the goal of preventing arthropathy. Our primary aim was to evaluate the joint outcomes of treated subjects using magnetic resonance imaging (MRI) and physical examination as outcome measures.

METHODS

Ankles, elbows and knees (index joints) of 24 subjects (median [range] age at start of therapy, 1.6 [1-2.5] years) with severe hemophilia A enrolled in the Canadian Hemophilia Primary Prophylaxis Study (CHPS) were examined by MRI at a median age of 8.8 years (range 6.2-11.5 years). Subjects were treated with TPP using a recombinant factor VIII concentrate, starting once weekly and escalating in frequency and dose according to frequency of bleeding.

RESULTS

Osteochondral changes (cartilage loss/subchondral bone damage) were detected in 9% (13/140) of the index joints and 50% (12/24) of study subjects. Osteochondral changes were restricted to joints with a history of clinically reported joint bleeding. Soft tissue changes were detected in 31% (20/65) of index joints with no history of clinically reported bleeding (ankles 75% (12/16); elbows 19% (6/32); and knees 12% (2/17)). In these apparently 'bleed free' index joints hemosiderin deposition was detected by MRI in 26% (17/65) of joints (ankles 63% (10/16); elbows 16% (5/32), and knees 12% (2/17)).

CONCLUSION

TPP did not completely avoid the development of MRI-detected structural joint changes in hemophilic boys in this prospective study. A longer period of follow-up is required for assessment of the longitudinal course of these early changes in hemophilic arthropathy, detected using a sensitive imaging technique (MRI).

Wavelets and fuzzy relational classifiers: a novel diffusion-weighted image analysis system for pediatric metabolic brain diseases

The diffusion-weighted imaging (DWI) technique can be utilized to investigate a variety of diseases. We propose an automated pilot system, which assists in the diagnosis of metabolic brain diseases, utilizing the DWI. In this study, DWI images are preprocessed and exponential apparent diffusion coefficient (eADC) images are produced. The eADC images are later brain extracted and normalized to a standard brain template. Subsequently, we utilized wavelets to denoise the eADC images. The images are rectified, thresholded and now conspicuous abnormal regions are subsequently identified utilizing different brain atlases. Abnormal regions constitute the features that will be used by a fuzzy relational classifier in order to categorize the diseases. A sensitivity and specificity of 60% and 93.33%, respectively, in detecting metabolic brain diseases have been achieved.

PCA-SGA implementation in classification and disease specific feature extraction of the brain MRS signals

The medical diagnostic systems often suffer from the high dimensional data. In this study, Principle Component Analysis (PCA) has been used for dimensionality reduction of the brain Magnetic Resonance Spectroscopy (MRS) signals. Afterwards, the Simple Genetic Algorithms (SGA) is utilized in order to classify different brain diseases. SGA is later used to extract MRS signal features in case of metabolic brain diseases (MD). The PCA-SGA implementation received the specificity of 89.91%. The SGA was able to achieve the sensitivity of 84.84% and positive predictivity of 88.46% in extracting disease specific MRS signal features.

Tailored prophylaxis in severe hemophilia A: interim results from the first 5 years of the Canadian Hemophilia Primary Prophylaxis Study

BACKGROUND

Prophylactic treatment for severe hemophilia A is likely to be more effective than treatment when bleeding occurs, however, prophylaxis is costly. We studied an inception cohort of 25 boys using a tailored prophylaxis approach to see if clotting factor use could be reduced with acceptable outcomes.

METHODS

Ten Canadian centers enrolled subjects in this 5-year study. Children were followed every 3 months at a comprehensive care hemophilia clinic. They were initially treated with once-weekly clotting factor; the frequency was escalated in a stepwise fashion if unacceptable bleeding occurred. Bleeding frequency, target joint development, physiotherapy and radiographic outcomes, as well as resource utilization, were determined prospectively.

RESULTS

The median follow-up time was 4.1 years (total 96.9 person-years). The median time to escalate to twice-weekly therapy was 3.42 years (lower 95% confidence limit 2.05 years). Nine subjects developed target joints at a rate of 0.09 per person-year. There was an average of 1.2 joint bleeds per person-year. The cohort consumed on average 3656 IU kg(-1)year(-1) of factor (F) VIII. Ten subjects required central venous catheters (three while on study); no complications of these devices were seen. One subject developed a transient FVIII inhibitor. End-of-study joint examination scores--both clinically and radiographically--were normal or near-normal.

CONCLUSIONS

Most boys with severe hemophilia A will probably have little bleeding and good joint function with tailored prophylaxis, while infusing less FVIII than usually required for traditional prophylaxis.

Compatible scales for progressive and additive MRI assessments of haemophilic arthropathy

The international MRI expert subgroup of the International Prophylaxis Study Group (IPSG) has developed a consensus for magnetic resonance imaging (MRI) scales for assessment of haemophilic arthropathy. A MRI scoring scheme including a 10 step progressive scale and a 20 step additive scale with identical definitions of mutual steps is presented. Using the progressive scale, effusion/haemarthrosis can correspond to progressive scores of 1, 2, or 3, and synovial hypertrophy and/or haemosiderin deposition to 4, 5, or 6. The progressive score can be 7 or 8 if there are subchondral cysts and/or surface erosions, and it is 9 or 10 if there is loss of cartilage. Using the additive scale, synovial hypertrophy contributes 1-3 points to the additive score and haemosiderin deposition contributes 1 point. For osteochondral changes, 16 statements are evaluated as to whether they are true or false, and each true statement contributes 1 point to the additive score. The use of these two compatible scales for progressive and additive MRI assessments can facilitate international comparison of data and enhance the accumulation of experience on MRI scoring of haemophilic arthropathy.

Fatal ethibloc embolization of vertebrobasilar system following percutaneous injection into aneurysmal bone cyst of the second cervical vertebra

A 4-year-old boy developed progressive neck pain and an expansile osteogenic lesion of C2; the diagnosis was an aneurysmal bone cyst. An image-guided biopsy with 3D CT planning was performed followed by Ethibloc injection into the aneurysmal bone cyst. Subsequent CT and MR images demonstrated embolization material in the vertebrobasilar system, and the patient died of brain stem and cerebellar infarction 23 hours after the intervention. The course of events and technical considerations are discussed.

Sensitivity of a clinical examination to predict need for radiography in children with ankle injuries: a prospective study

BACKGROUND

Radiographs are ordered routinely for children with ankle trauma. We assessed the predictive value of a clinical examination to identify a predefined group of low-risk injuries, management of which would not be affected by absence of a radiograph. We aimed to show that no more than 1% of children with low-risk examinations (signs restricted to the distal fibula) would have high-risk fractures (all fractures except avulsion, buckle, and non-displaced Salter-Harris I and II fractures of the distal fibula), and to compare the potential reduction in radiography in children with low-risk examinations with that obtained by application of the Ottawa ankle rules (OAR).

METHODS

Standard clinical examinations and subsequent radiographs were prospectively and independently evaluated in two tertiary-care paediatric emergency departments in North America. Eligible participants were healthy children aged 3-16 years with acute ankle injuries. Sample size, negative and positive predictive values, sensitivity, and specificity were calculated. McNemar's test was used to compare differences in the potential reduction in radiographs between the low-risk examination and the OAR.

FINDINGS

607 children were enrolled; 581 (95.7%) received follow-up. None of the 381 children with low-risk examinations had a high-risk fracture (negative predictive value 100% [95% CI 99.2-100]; sensitivity 100% [93.3-100]). Radiographs could be omitted in 62.8% of children with low-risk examinations, compared with only 12.0% reduction obtained by application of the OAR (p<0.0001).

INTERPRETATION

A low-risk clinical examination in children with ankle injuries identifies 100% of high-risk diagnoses and may result in greater reduction of radiographic referrals than the OAR.

An orange a day keeps the doctor away: scurvy in the year 2000

Scurvy has been known since ancient times, but the discovery of the link between the dietary deficiency of ascorbic acid and scurvy has dramatically reduced its incidence over the past half-century. Sporadic reports of scurvy still occur, primarily in elderly, isolated individuals with alcoholism. The incidence of scurvy in the pediatric population is very uncommon, and it is usually seen in children with severely restricted diets attributable to psychiatric or developmental problems. The condition is characterized by perifollicular petechiae and bruising, gingival inflammation and bleeding, and, in children, bone disease. We describe a case of scurvy in a 9-year-old developmentally delayed girl who had a diet markedly deficient in vitamin C resulting from extremely limited food preferences. She presented with debilitating bone pain, inflammatory gingival disease, perifollicular hyperkeratosis, and purpura. Severe hypertension without another apparent secondary cause was also present, which has been previously undescribed. The signs of scurvy and hypertension resolved after treatment with vitamin C. The diagnosis of scurvy is made on clinical and radiographic grounds, and may be supported by finding reduced levels of vitamin C in serum or buffy-coat leukocytes. The response to vitamin C is dramatic. Clinicians should be aware of this potentially fatal but easily curable condition that is still occasionally encountered among children.

Radiologic mimics of juvenile rheumatoid arthritis

Established criteria for diagnosis of juvenile rheumatoid arthritis require consideration of a number of other joint arthropathies and arthritides. In this pictorial essay, we present an approach to those common and uncommon disorders that should be considered and may be mistaken for juvenile rheumatoid arthritis.

MR imaging of simple bone cysts in children: not so simple

OBJECTIVE

The unicameral bone cyst (UBC) is a common cystic bone lesion seen in children. We review and summarize its MR findings, focusing on their appearance following contrast enhancement, and correlating them to known histologic features of UBC.

SUBJECTS AND METHODS

A retrospective review of 20 cases (13 boys, 7 girls; age range, 1-17 years; mean age, 8.9) diagnosed as UBC was conducted. Clinical histories, radiographic and MR features, follow-up data, and available pathologic findings were noted.

RESULTS

At initial presentation 18 (90 %) of the patients with UBC had a history of acute or remote pathologic fracture. Cysts with history of fracture displayed heterogeneous fluid signals on T1-(n = 9, 50%), and T2-weighted (n = 15, 83 %) MR images. Gadolinium-enhanced images were obtained in 15 of the 18 UBC cases with history of previous fracture. All showed enhancement with focal, thick peripheral, heterogeneous, or subcortical patterns. Focal nodules of homogeneous enhancement (diameter > 1 cm) within the UBC (n = 5) correlated with areas of ground-glass opacification on plain film. Other interesting MR features were fluid-fluid levels (n = 11), "fallen-leaf" sign (n = 1), soft-tissue changes (n = 2), and detection of septations not seen on plain film (n = 2).

CONCLUSION

UBCs frequently appear complicated on MR imaging, with heterogeneous fluid signals and regions of nodular and thick peripheral enhancement related to previous pathologic fracture and early healing.

Development and duration of radiographic signs of bone healing in children

OBJECTIVE

Few articles report the evaluation of pediatric fracture healing and dating based on radiographic appearance. We established a timetable for expected radiographic changes visible during bone healing in otherwise healthy children.

MATERIALS AND METHODS

We examined 707 radiographs of fractured forearms in 141 patients. Each fracture was assessed by a pediatric radiologist who was unaware of the timing of the initial injury. Assessment included the following features: fracture margins, fracture gap, periosteal reaction, callus, bridging, and remodeling. The time interval between injury and the appearance of the radiographic features and the duration of radiographic signs were determined and correlated with age, sex, angulation, displacement, and location.

RESULTS

Sclerosis at the fracture margins was evident in 85% of fractures 5 weeks after injury. Widening of the fracture gap was observed in 62% of fractures at 6 weeks. Periosteal reaction was evident on all images by 4 weeks, and after 7 weeks, periosteal reaction was separable from cortex in only 10% of fractures. Fracture callus had a density equal to or greater than that of adjacent cortex 10 weeks after injury in 90% of fractures.

CONCLUSION

A wide variation exists in the appearance and duration of the radiographic signs of bone healing. Marginal sclerosis should be an expected radiographic sign of normal bone healing. Applying maximum and minimum time spans to objective radiographic signs may aid in fracture dating.

The use of magnetic resonance imaging in the diagnosis and followup of pediatric pelvic rhabdomyosarcoma

PURPOSE

Previous radiological descriptions of pelvic rhabdomyosarcoma emphasized ultrasonography and computerized tomography (CT). Few reports are available on the use of magnetic resonance imaging (MRI) for diagnosing and following pelvic rhabdomyosarcoma. We retrospectively compared MRI to CT for diagnosing and following children with pelvic rhabdomyosarcoma.

MATERIALS AND METHODS

We treated 4 boys and 3 girls for pelvic rhabdomyosarcoma. Initial and followup evaluations included pelvic CT and MRI at intervals determined by treatment and disease status. We retrospectively reviewed the clinical charts and imaging studies of these patients. The initial radiological report was evaluated and then 1 radiologist reviewed all studies. Attention was directed toward identifying lesions revealed by CT or MRI but not by the other modality.

RESULTS

MRI detected all lesions shown by CT. On the other hand, MRI detected residual disease in 1 case that was not demonstrated by CT. In 2 other patients MRI was superior to CT for delineating the local extent of disease, especially urethral involvement.

CONCLUSIONS

Compared with CT, MRI improves the detection of residual pelvic rhabdomyosarcoma. Tissue planes are well delineated, allowing more accurate assessment of tumor invasion into adjacent structures. MRI is the imaging modality of choice for following pediatric patients with pelvic rhabdomyosarcoma.

User acceptability--a critical success factor for picture archiving and communication system implementation

The Department of Diagnostic Imaging at the Hospital for Sick Children (HSC), Toronto, implemented a picture archiving and communication system (PACS) during the last year. This report describes our experience from the point of view of user acceptability. Based on objective data, the following key success factors were identified: user involvement in PACS planning, training, technical support, and rollout of pilot projects. Although technical factors are critical and must be addressed, the main conclusion of our study is that other nontechnical factors need to be recognized and resolved. Recognition of the importance of these factors to user acceptance and clear communication and consultation will help reduce negative user attitudes and increase the chance of a successful PACS implementation.

MR imaging of paediatric uterovaginal anomalies

BACKGROUND

Transabdominal ultrasound (US) has not proved completely reliable in Müllerian duct anomalies. One study has shown it useful in obstructed uterovaginal anomalies. We are unaware of a study that has used endovaginal ultrasound in children to investigate uterovaginal anomalies. Magnetic resonance imaging (MRI) is now gaining wide acceptance in imaging congenital abnormalities of the genital tract.

OBJECTIVE

To identify the problems and potential pitfalls of using MRI to evaluate the female genital tract in paediatric patients.

MATERIALS AND METHODS

A retrospective review of the MRI scans of 19 patients, aged 3 months to 19 years (mean 14 years), with uterovaginal anomalies.

RESULTS

The uterovaginal anomalies were categorised into three groups: (1) congenital absence of the Müllerian ducts, or the Mayer-Rokitansky-Kuster-Hauser syndrome (n = 7), (2) disorders of vertical fusion (n = 2) and (3) disorders of lateral fusion (n = 10).

CONCLUSIONS

MRI is a reliable method for evaluating paediatric uterovaginal anomalies, but should be analysed in conjunction with other imaging modalities (US and genitography). Previous surgery makes interpretation more difficult and, if possible, MRI should be carried out prior to any surgery. An accurate MRI examination can be extremely helpful prior to surgery and it is important for the radiologist to have knowledge of how these complex anomalies are managed and what pitfalls to avoid.

Multidisciplinary evaluation of the distended abdomen in critically ill infants and children: the role of bedside sonography

Abdominal distention and metabolic acidosis are common in critically ill infants and children, and can be manifestations of an intra-abdominal catastrophe. This series demonstrates the value of bedside sonography (US) in this difficult assessment. Eight infants and children presented with the above situation. Seven were immediately post-cardiopulmonary resuscitation and none had antecedent histories of abdominal pain or bilious vomiting. Abdominal radiographs could not rule out intra-abdominal pathology such as ischemic bowel. Review of all laboratory and radiological data showed US to be a discerning modality for acute bowel pathology. A characteristic pattern of echogenic ascites, thickened bowel wall, dilated, fluid-filled bowel lumen, and lack of peristalsis was seen in those children with gangrenous bowel. Sonographic examination accurately predicted the status of the bowel in all patients. Four patients survived: two had segmental ileal necrosis, one had localized gangrene of the jejunum (twice), and one had necrotic bowel from a closed-loop obstruction. The four who died had malrotation with volvulus (two), superior mesenteric venous thrombosis, and one was immunocompromised with pulmonary aspiration. We conclude that bedside US can be extremely valuable as an adjunct in assessing the abdomen and diagnosing gangrenous bowel in critically ill infants and children.

Ultrasonographic and clinical predictors of intussusception

OBJECTIVE

The objective of this study was to determine the positive and negative clinical predictors of intussusception and the correlation of ultrasonography and air enema in establishing this diagnosis.

STUDY DESIGN

This was a prospective descriptive cohort study.

SETTING

This study was performed in a tertiary care pediatric emergency department.

PARTICIPANTS

Eighty-eight of 245 candidates were assessed for clinical predictors of intussusception. All 245 cases were examined for correlation between ultrasonography and air enema.

INTERVENTIONS

A questionnaire, ultrasonography, and air enema were used.

RESULTS

Thirty-five of the 88 patients assessed for clinical predictors were positive for intussusception. Significant positive predictors were right upper quadrant abdominal mass (positive predictive value [PPV] 94%), gross blood in stool (PPV 80%), blood on rectal examination (PPV 78%), the triad of intermittent abdominal pain, vomiting, and right upper quadrant abdominal mass (PPV 93%, p = 0.0001), and the triad with occult or gross blood per rectum (PPV 100%, p = not significant). Significant negative predictors were a combination of > or = 3 of 10 clinically significant negative features (negative predictive value 77%, p = 0.035). Of the total 245 cases, intussusception (as confirmed by doughnut, target, or pseudokidney sign) was ruled out by ultrasonography in 97.4%. Alternate ultrasound findings comprised 27% of negative cases.

CONCLUSIONS

Excellent positive predictors of intussusception were identified prospectively. Although no reliable negative predictors were found, patients at low risk may be screened by ultrasonography.

Patellar enthesopathy in childhood: a new clinical and radiographic observation

Enthesitis occurs commonly in patients with seronegative spondyloarthropathies. The patella is frequently affected by enthesopathy, but overgrowth has not been reported as a manifestation of enthesitis in pediatrics. We describe 3 patients with seronegative enthesopathy and arthropathy syndrome and patellar overgrowth.

X linked spondyloepiphyseal dysplasia: a clinical, radiological, and molecular study of a large kindred

X linked spondyloepiphyseal dysplasia (SEDT) is a rare disorder characterised by disproportionate short stature and degenerative changes in the spine and hips. We report a large kindred with 11 affected males and 17 obligate carrier females. We examined clinically and radiographically the seven living affected males and obtained detailed historical information on the four dead. The natural history was characterised by normal growth until late childhood. Decreased growth velocity was the earliest detectable abnormality. In adulthood, four subjects required hip replacements but disability was minimal. Clinical examinations showed a characteristic habitus with short stature (> 2 SD below the mean) and a decreased upper segment to lower segment ratio (> 1 SD below the mean) in all affected subjects. Also noted were scoliosis (6/7), and decreased range of hip rotation (6/7), and decreased range of movement of the lumbar spine (4/7). Radiographic evaluations were available on nine subjects. Radiographic changes were evident in two patients in childhood; findings in adulthood included narrow disc spaces (8/9), platyspondyly (7/9), the characteristic central and posterior hump of the vertebral bodies (6/9), bony spurs (7/ 8), and pelvic abnormalities (7/9). We also systematically evaluated eight obligate carrier females. They could not be distinguished from the general population on clinical and radiographic findings. Linkage analysis showed significant linkage with markers on Xp22, as previously reported. A recombinant event between DXS43 and DXS207 places the locus distal to DXS43.

Infantile myositis presenting in the neonatal period

Infantile myositis, observed in the neonatal period, is rare and may be confused with congenital muscular dystrophy. The patient presented here showed evidence of a myopathy with in utero onset with intrauterine growth retardation and decreased fetal movements. A muscle biopsy demonstrated characteristic perifascicular atrophy and inflammatory infiltrates. Initial magnetic resonance (MR) examination revealed high signal intensity in several proximal muscle groups. With subsequent corticosteroid treatment, the patient's symptoms, clinical course and MR findings have gradually improved. The diagnosis of infantile myositis should be established as early as possible, since proper treatment can lead to resolution of clinical symptomatology and MR findings.

Reliability of the chest radiograph in the diagnosis of lower respiratory infections in young children

OBJECTIVE

This study was conducted to determine the reliability of detecting features and making diagnoses of lower respiratory infections from chest radiograms in young infants.

METHODS

Forty chest radiograms of infants younger than 6 months of age admitted with lower respiratory tract infection to a tertiary care pediatric hospital were independently reviewed on two separate occasions by three pediatric radiologists blinded to the patients' clinical diagnoses. For each radiograph the radiologists noted whether a feature was present, absent or equivocal on a standardized form. The features examined were hyperinflation, peribronchial thickening, perihilar linear opacities, atelectasis and consolidation. On the same form each radiologist indicated whether the radiograph was normal or showed airways and/or airspace disease. Within and between observer agreement were calculated by the average weighted kappa statistic.

RESULTS

Within observer agreement for the radiologic features of hyperinflation, peribronchial wall thickening, perihilar linear opacities, atelectasis and consolidation were 0.85, 0.76, 0.87, 0.86 and 0.91, respectively. The between observer kappa results for these features were 0.83, 0.55, 0.82, 0.78 and 0.79, respectively. The within and between observer kappa statistics for interpretation of the radiographic features were best for airspace disease (within, 0.92; between, 0.91), and lower for normal (within, 0.80; between, 0.66) radiogram and for airways disease (within, 0.68; between, 0.48). The presence of consolidation was highly correlated with a diagnosis of airspace disease by all three radiologists.

CONCLUSIONS

Clinicians basing the diagnosis of lower respiratory infections in young infants on radiographic diagnosis should be aware that there is variation in intraobserver and interobserver agreement among radiologists on the radiographic features used for diagnosis. There is also variation in how specific radiologic features are used in interpreting the radiogram. However, the cardial finding of consolidation for the diagnosis of pneumonia appears to be highly reliable.

Terminal deletion of the long arm of chromosome 3 [46,XX,del(3)(q27-->qter)]

We report on a terminal deletion of the long arm of chromosome 3 [46,XX,del(3)(q27-->qter)] in a female newborn infant who died 45 hours after delivery and had multiple congenital abnormalities including bilateral anophthalmia, congenital heart disease, and abnormal genitalia. The findings are compared to those of four previously reported cases with terminal del (3q).

Imaging patients with Wilms tumor

Imaging plays a significant role in the management of Wilms tumor. Appropriate imaging continually must undergo refinement related to improvements in therapy and imaging modalities. We must recognize the need to demonstrate effectiveness in all phases of patient management and address the contentious issue of maximizing yield and minimizing cost.

Osteoarthritis staging: comparison between magnetic resonance imaging, gross pathology and histopathology in the rhesus macaque

Although osteoarthritis (OA) is the most common cause of articular skeletal disability in humans, assessing progression (staging) with noninvasive methods remains a major clinical problem. Using the rhesus macaque animal model, the objective of this study was to compare OA staging by noninvasive magnetic resonance imaging (MRI) against gross pathology and histopathology. Right knee joints from 18 rhesus macaques were used in this study. Using a four-point ordinal scale for each of the above-mentioned modalities, the lateral and medial femoral condyle and tibial plateau of each knee joint was independently scored for OA severity, i.e. normal, mild OA, moderate OA and severe OA. Correlation between each staging system was performed using Stuart's Tau-c correlation coefficient. By our criteria, MRI staging correlated as well with gross pathology (tau = 0.75) and histopathology (tau = 0.80) as did gross pathology with histopathology (tau = 0.78). Our study shows that MRI is a promising noninvasive modality to evaluate the severity of OA. MRI appears to be sensitive for demarcating the presence and extent of focal OA cartilage lesions. However, at this time, while MRI is sensitive for detecting OA change it cannot distinguish between certain lesions such as superficial cartilage matrix fibrillation and hypertrophy both of which show elevated signal intensity.

Radiologic features of gastric outlet obstruction in infants after long-term prostaglandin administration

Long-term prostaglandin (PG) therapy has recently been associated with gastric mucosal hyperplasia. We reviewed the clinical and radiologic (especially sonographic) records of eight patients with complex congenital heart disease who were on PG therapy. Feeding problems, vomiting, and abdominal distension were present in six patients. Barium meal revealed antral narrowing in three patients, suggestive of hypertrophic pyloric stenosis in two. Sonography showed a variable degree of increased gastric mucosal lobulation often accompanied by a marked polypoid or lobular appearance. Cortical hyperostosis related to PG therapy was seen in three patients. PG-associated gastric mucosal hyperplasia can cause feeding problems and pronounced gastric lobulation.

Magnetic resonance imaging of the iliofemoral arteries after balloon dilation angioplasty of aortic arch obstructions in children

BACKGROUND

We wished to determine the nature and incidence of changes in the iliofemoral arteries after balloon dilation angioplasty (BDA) for aortic arch obstruction in children and to determine the reliability of gradient magnetic resonance imaging (MRI) in their detection.

METHODS AND RESULTS

Sixty-three children, including 62 with and 1 without arch obstruction, underwent MRI of the iliofemoral vessels. Of these, 36 patients had undergone transfemoral BDA (7 after previous transfemoral diagnostic catheterization), 12 had undergone diagnostic transfemoral catheterization but not BDA, and 15 had no history of femoral arterial catheterization. The iliofemoral arteries were normal on MRI in all 15 children without catheterization. Among the 36 children who had undergone BDA, the ipsilateral iliofemoral artery was normal in 15, mildly narrowing in 7, and severely stenotic or occluded in 14 (39%), including 6 of 9 patients treated for acute femoral artery thrombosis and 8 with no history of femoral artery thrombosis. Two patients had documentation of progressive obstruction. Six patients had concordant conventional angiography. There was a significant correlation between the number of balloon catheters used for the angioplasty and severe occlusive changes. Nine of 19 patients who had undergone diagnostic transfemoral catheterization had severe obstructive changes on MRI; 8 of 9 weighed < 10 kg at catheterization.

CONCLUSIONS

Obstructive lesions of the iliofemoral arteries are common after transfemoral BDA of arch obstructions (58%) and can be reliably evaluated with gradient MRI. Catheter size and manipulation are the main contributing factors.

Three-dimensional imaging of the pediatric trachea in congenital tracheal stenosis

Technological advances in three-dimensional computer software packages have resulted in fairly widespread acceptance of 3D imaging for musculoskeletal studies. We have recently applied this technology to axial CT images of the pediatric trachea for children with congenital tracheal stenosis, in an effort to replace tracheo-bronchography with a safer, less invasive modality to image the pediatric trachea. This method has provided our surgical colleagues with images which they find easier to interpret because they are more anatomically oriented with respect to regional mediastinal structures, which can be included or removed from the image at will. The images can also be manipulated and rotated through various projections, thus facilitating surgical planning.

Plain abdominal radiography in suspected intussusception: a reassessment

The objectives of the study were (1) to determine the interobserver variation in interpretation of abdominal radiographs in children with clinically suspected intussusception, and (2) to determine the diagnostic value of abdominal radiographs in these patients. One hundred and eighty-two plain abdominal radiographic examinations (AXR) performed in children with clinically suspected intussusception were reviewed blind to the clinical history and findings of air enema. The presence or absence of nine AXR signs relevant to intussusception was documented. Each AXR was categorized as equivocal, positive or negative for intussusception, with the aim of achieving no false negatives. Interobserver variation in the identification of AXR signs and radiologic diagnoses was calculated using the kappa statistic for 60 cases assessed independently by three observers. Using the findings of air enema as gold standard, the prevalence of AXR signs in all patients with (60) and without (122) intussusception was determined and their diagnostic values calculated. The best observer agreement was for the presence of sparse small bowel gas (supine, k = 0.68) and the worst for the presence of cecal gas (erect, k = 0.18). All three observers agreed intussusception to be present or absent in only 7 of 60 cases and the majority agreement was equivocal in more than half. Overall agreement between observers for the diagnosis of intussusception was k = 0.30. The best positive predictors of intussusception were the soft tissue mass and sparse large bowel gas, with likelihood ratios of 3.9 and 2.5. Cecal feces predicted against intussusception, likelihood ratio 0.11. AXR was equivocal in 53%, positive in 21% and negative in 26%. Where a firm radiographic diagnosis was made, the diagnostic accuracy of AXR was 84%.(ABSTRACT TRUNCATED AT 250 WORDS)

Potentially misleading bone scan findings in patients with hepatoblastoma

Eleven patients who underwent nuclear medicine bone scanning were reviewed to determine the incidence of bone scan abnormalities associated with hepatoblastoma. Of these, six patients had abnormal bone scan findings--four with focal involvement. Correlating plain radiographs and/or follow-up nuclear bone scans were available for three of these four. All plain films indicated the presence of osteoporosis. Follow-up scans showed improvement or resolution of abnormalities. None of the patients had documented metastatic bone disease. While there has been no prior reported association, the authors attribute the abnormal bone scan findings to a paraneoplastic syndrome of osteoporosis associated with this primary tumor. They conclude that bone scanning is not routinely indicated in the initial diagnostic staging of hepatoblastoma.

Sonographic diagnosis of developmental dysplasia of the hip: importance of increased thickness of acetabular cartilage

OBJECTIVE

Dynamic and static sonography has become the imaging technique of choice in the diagnosis and follow-up of developmental dysplasia of the hip. The purpose of this study was to determine the value of using the thickness of acetabular cartilage as measured on sonograms as a discriminating factor in the diagnosis of developmental dysplasia.

SUBJECTS AND METHODS

We evaluated 220 consecutive hips in 110 infants referred for sonography because of possible developmental dysplasia (referred group). We also evaluated 66 hips in 33 infants who had normal findings on physical examination and no clinical or sonographic evidence of the abnormality (control group). The thickness of the acetabular cartilage, the alpha angle, and the presence of subluxation or dislocation on sonograms were recorded. Follow-up clinical and sonographic examinations were performed between 6 weeks and 6 months after the initial examinations in 19 patients in whom the thickness of the acetabular cartilage was increased (> 3.5 mm) and in 20 patients in whom the thickness was in the normal range (< 3.5 mm). All 39 patients who had follow-up examinations were from the referred group, and all these hips were normal according to conventional sonographic criteria on the initial examination.

RESULTS

Of the 220 hips in the referred group, 170 were initially classified as normal according to traditional sonographic standards, and 50 were classified as dysplastic (alpha angle < 55 degrees with or without subluxation or dislocation). The mean thickness of the acetabular cartilage in the control group was 2.6 mm (1 SD = 0.37) as compared with 4.6 mm (1 SD = 0.71) for the dysplastic hips in the referred group. The mean thickness in the hips classified as normal in the referred group was 3.0 mm. Nineteen hips in the referred group in which the thickness of the acetabular cartilage was greater than in the control group (i.e., > 3.4 mm) were imaged again during follow-up examinations. Sixteen of these 19 hips had become clinically unstable or dysplastic according to conventional sonographic criteria.

CONCLUSION

The results suggest that sonographic evidence of increased thickness of the acetabular cartilage is an early sign of developmental dysplasia of the hip and that close follow-up of infants with this abnormality is indicated.

Thrombosis of the portal venous system after splenectomy for pediatric hematologic disease

Splenic, portal, or mesenteric venous thrombosis after splenectomy for hematologic disease has not been reported in the pediatric literature. It is a rare complication associated with significant morbidity and mortality in adult reports. Between 1981 and 1991, 3 patients (13-year-old boy with hereditary elliptocytosis [HE], 13-year-old boy with thalassemia intermedia [TI], and 18-year-old girl with idiopathic thrombocytopenic purpura [ITP]) presented with abdominal pain, nausea, with or without fever, at 4, 11, and 13 days postsplenectomy, respectively. Abdominal Doppler ultrasound (US) and/or computed tomography (CT) showed: (1) an intraluminal filling defect with partial obstruction to flow in the right branch of the portal vein with the remaining vessels patent (HE); (2) splenic vein thrombosis with complete occlusion of the main portal vein and proximal superior mesenteric vein (TI); and (3) complete thrombosis of the splenic vein, proximal superior mesenteric vein and portal vein (including central radicles), with retrogastric collateralization (ITP). Subsequent imaging showed either complete resolution of vascular obstruction on no treatment (patient 1), or portal venous cavernomatous transformation with hepatofugal flow after 6 months of systemic anticoagulation (patients 2 and 3), and all 3 patients are currently asymptomatic. Postoperative sonographic evaluation of a consecutive series of pediatric splenectomies for hematologic disease (n = 16), was performed at a median of 51 days (range, 3 to 124). This demonstrated one case of asymptomatic left portal venous thrombosis with subsequent recanalization in the absence of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Complications of use of the Ilizarov technique in the correction of limb deformities in children

We reviewed the records of the first forty patients who had been managed at our institution with the Ilizarov technique for the correction of limb deformities, including limb-length inequality, to delineate the complications of this method of treatment. The duration of follow-up ranged from two and one-half to four years. A complication was defined as any untoward occurrence to a patient either during the course of treatment or after removal of the fixator. A major complication was considered one that necessitated an additional operative procedure; caused lasting sequelae, such as malunion, deformation of new bone, joint contracture or stiffness, or nerve palsy; or prolonged the treatment. A minor complication was regarded as one that responded to non-operative treatment and did not cause lasting sequelae, such as transient decreased motion of the joint, paresthesia, or pin-track infection. There were eighty-eight complications--thirty-eight, major, and the remaining fifty, minor--in the sixty-one segments of the limb that were treated; this represented an average of almost one and one-half complications for each segment. Twenty-nine unplanned operative procedures were performed either during treatment with the Ilizarov technique or after removal of the fixator. As anticipated, the prevalence of major complications was highest in the patients who had had more complex and prolonged treatment. Such complications were encountered less often as the surgeons gained experience with the procedure, but the rate of minor complications remained relatively constant, despite the increased experience.(ABSTRACT TRUNCATED AT 250 WORDS)

MR evaluation of the temporomandibular joint in juvenile rheumatoid arthritis

Temporomandibular joint (TMJ) disease is uncommon in children but frequently occurs in juvenile rheumatoid arthritis (JRA). Involvement is often asymptomatic; however, it can lead to growth disturbances and facial deformity. Thirty TMJs in 15 children (11 girls and 4 boys aged 3.5-18 years) with JRA were evaluated clinically and by MRI. Plain films were reviewed when available. Magnetic resonance imaging parameters included T1-weighted and in some cases T2-weighted or gradient recall echo sequences. We assessed condylar configuration, glenoid fossa changes, presence of erosions, disk abnormality, range of motion, and presence of joint effusions or pannus. Abnormalities included cortical erosions (n = 19), disk thinning (n = 18), and perforation (n = 2). Reduction of joint movement (n = 20), joint locking (n = 3), and pannus/effusions (n = 5) were also found. Magnetic resonance imaging is a useful technique for the detection of TMJ involvement in JRA. Early detection and therapeutic intervention may lessen or prevent subsequent deformities.

Osteoarthritis in rhesus macaques: assessment of cartilage matrix quality by quantitative magnetic resonance imaging

To assess cartilage quality with anatomical location and extent of osteoarthritis (OA), magnetic resonance imaging (MRI) of the knee joint from rhesus monkeys was performed. MRI measurements--T1 and T2 relaxation times, proton density and cartilage thickness were taken from 8 equal segments of articular cartilage volumes extending from anterior to posterior edge of 1 mm sagittal slices. To grade the severity of OA in each quadrant of the knee joint a modified Mankin score was applied on the histological sections. Our results suggest that MR relaxation times and proton density values vary with the severity of osteoarthritis.

Gastric-outlet obstruction induced by prostaglandin therapy in neonates

BACKGROUND

An infusion of prostaglandin E1 is widely used to maintain patency of the ductus arteriosus in neonates with congenital heart disease. After gastric-outlet obstruction was recognized in several infants who received prostaglandin E1, we studied the association between the drug and this complication.

METHODS

We evaluated all neonates who received prostaglandin E1 in our hospital between October 1, 1989, and September 30, 1991, for clinical, radiologic, or pathological evidence of acute gastric-outlet obstruction.

RESULTS

Of the 74 neonates evaluated, 65 had no signs of gastric obstruction and were considered normal; 5 had clinical and radiologic or pathological evidence of gastric obstruction consistent with the presence of antral mucosal hyperplasia. The remaining four neonates had clinical signs of gastric obstruction, but no radiologic or pathological examinations were performed. The 5 neonates with antral hyperplasia had received prostaglandin E1 for longer periods (mean [+/- SD] duration, 569 +/- 341 hours) than the 65 normal neonates (54 +/- 58 hours, P less than 0.001) or the 4 neonates with clinical signs of gastric obstruction (119 +/- 60 hours, P less than 0.05). The cumulative dose of prostaglandin E1 was higher in the neonates with antral hyperplasia (2982 +/- 1392 micrograms per kilogram of body weight) than in the normal neonates (279 +/- 270 micrograms per kilogram, P less than 0.001) or the neonates with signs of gastric obstruction (528 +/- 306 micrograms per kilogram, P less than 0.01). In two neonates with antral hyperplasia, the cessation of therapy lessened the gastric-outlet obstruction.

CONCLUSIONS

The administration of prostaglandin E1 to neonates can cause gastric-outlet obstruction due to antral hyperplasia. Neonates who receive prostaglandin E1 at recommended doses for more than 120 hours should be closely monitored for evidence of antral hyperplasia.

Pediatric pelvis: radiographic appearance in various congenital disorders

This article presents the spectrum of pelvic abnormalities in developmental diseases of bone. The pelvis comprises the ilium, ischium and pubis, and the sacrum. Knowledge of pelvic embryology and normal development is essential in recognizing pelvic abnormalities and disorders, which involve the number of bone elements, rate of ossification, density, and size or shape. Anarchic development of bone and dysplasias identifiable at birth must also be considered. The pelvis is important in the evaluation of such disorders because of the frequent, varied, and often specific radiologic abnormalities. The pelvis may also be the first evidence for a congenital malformation syndrome because it is often included in routine radiographic examinations.

Reduction in tumor burden allowing partial nephrectomy following preoperative chemotherapy in biopsy proved Wilms tumor

During the last 6 years a treatment protocol of radiographic staging along with percutaneous biopsy to establish a histological diagnosis has been used in 37 patients with Wilms tumor. Combination chemotherapy was given for 4 to 6 weeks before definitive surgical resection. In 9 patients tumor shrinkage was sufficient to permit preservation of a portion of the affected kidney(s). In stage V disease partial nephrectomy was accomplished in 5 patients. In 4 additional patients with unilateral disease downstaging also allowed partial nephrectomy. The radiological and histological changes that allowed this limited surgery are analyzed and compared.

Spontaneous pneumothorax in cystic adenomatoid malformation. Unusual clinical and histologic features

Pneumothorax is a rare presentation of congenital cystic adenomatoid malformation (CCAM) in the newborn period and is presumed to be due to resuscitative measures. A previously well three-week-old baby presented with spontaneous tension pneumothorax due to CCAM. In the lung resection specimen, a malformation was seen, which in addition to the histologic changes of CCAM, showed diffuse vascular proliferation in the interstitium and lining of air space by type 2 pneumocytes. We propose that this is a new variant of CCAM rather than one of the classic three types. The unusual clinical manifestation may be related to the unusual histologic features.

Rare primary cranial vault and base of the skull tumors in children. Report of 30 cases with a short literature review

Twenty-six cases of rare primary cranial vault tumors are reported, together with 4 cases of primary tumors of the base of the skull and 3 cases of monostotic cranial neuroblastoma. Whereas some rare primary cranial vault tumors may present with characteristic radiographic patterns (e.g. hemangioma, aneurysmal bone cyst, osteoma, progonoma), most of them can be recognised only after histology. The most frequent tumor in the region of previous irradiation is osteosarcoma. The only "common" primary bone tumor of the base of the skull is chordoma. The radiological differential diagnosis of primary tumors of the skull vault and base is discussed.

An unusual case of craniofacial fibrous dysplasia presenting in early infancy

Fibrous dysplasia (FD) of bone is one of the most frequently encountered anomalies of skeletal development. It may involve one or more bones and, particularly when polyostotic, is sometimes associated with abnormal skin pigmentation and endocrine abnormalities. FD occurs mainly in large limb bones, ribs, and craniofacial bones in older children and young adults. Usually craniofacial involvement is detected because of local swelling or asymmetry of the face or head. Neurological symptoms, primarily due to involvement of the foramina, have been reported but are not common. Infantile fibrous dysplasia of the craniofacial region has rarely been reported.

A system for slit-lamp polaroid photography

A system is described in which a SX-70, Alpha Model II, Polaroid, single lens reflex camera, and photoflash unit can be quickly and sturdily mounted to a slit lamp. Such a system can take sharp anterior segment prints of the eye at all slit-lamp magnifications, with white light and in the flourescein mode. The heart of the unit is the modification of an assembly initially designed to attach the camera to a light microscope. The small flash unit and power supply were designed specifically for slit lamp usage. Examples of "instant" photos of the anterior segment at different magnifications are presented.