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.

Choosing outcome assessment tools in haemophilia care and research: a multidisciplinary perspective.

INTRODUCTION: The implementation of early long-term, regular clotting factor concentrate (CFC) replacement therapy ('prophylaxis') has made it possible to offer boys with haemophilia a near normal life. Many different regimens have reported favourable results, but the optimum treatment regimens have not been established and the cost of prophylaxis is very high. Both for optimizing treatment and reimbursement issues, there is a need to provide objective evidence of both short- and long-term results and benefits of prophylactic regimens. AIMS: This report presents a critical review of outcome measures for use in the assessment of musculoskeletal health in persons with haemophilia according to the International Classification of Functioning, Disability and Health (ICF). This framework considers structural and functional changes, activities and participation in a context of both personal and environmental factors. METHODS: Results were generated by a combination of a critical review of available literature plus expert opinion derived from a two day consensus conference between 48 health care experts from different disciplines involved in haemophilia assessment and care. Outcome tools used in haemophilia were reviewed for reliability and validity in different patient groups and for resources required. RESULTS AND CONCLUSION: Recommendations for choice of outcome tools were made according to the ICF domains, economic setting, and reason for use (clinical or research). The next step will be to identify a 'core' set of outcome measures for use in clinical care or studies evaluating treatment.

A Rare and Unusual Case of Burkitt's Lymphoma Presenting with a Prostate Mass in a 12-Year-Old Boy.

Burkitt's lymphoma is the most frequent subtype of non-Hodgkin's lymphoma in childhood. Radiographic findings are protean and can often overlap with other neoplastic and nonneoplastic processes. We present an unusual case of Burkitt's lymphoma in a 12-year-old boy presenting with a one-week history of urinary retention, dysuria, and "tailbone pain," as well as a 4-week history of jaw pain, initially treated as a dental abscess. On dental radiography, the patient was found to have resorption of alveolar bone adjacent to the lower first molars bilaterally, in keeping with "floating teeth," classically associated with Langerhans cell histiocytosis. Additionally, a large, eccentric, prostatic mass was noted, prompting the inclusion of rhabdomyosarcoma on the differential diagnosis, with subsequent definitive diagnosis of Burkitt's lymphoma on tissue and bone marrow biopsy. This case highlights the imaging overlap of these childhood neoplasms with an unusual lymphomatous prostate mass. It is important that the radiologists and pediatricians be aware of this potential overlap and the unusual presentation of Burkitt's lymphoma.

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.

Reliability and construct validity of the compatible MRI scoring system for evaluation of elbows in haemophilic children.

We assessed the reliability and construct validity of the Compatible MRI scale for evaluation of elbows, and compared the diagnostic performance of MRI and radiographs for assessment of these joints. Twenty-nine MR examinations of elbows from 27 boys with haemophilia A and B [age range, 5-17 years (mean, 11.5)] were independently read by four blinded radiologists on two occasions. Three centres participated in the study: (Toronto, n = 24 examinations; Atlanta, n = 3; Cuiaba, n = 2). The number of previous joint bleeds and severity of haemophilia were reference standard measures. The inter-reader reliability of MRI scores was substantial (ICC = 0.73) for the additive (A)-scale and excellent (ICC = 0.83) for the progressive (P)-scale. The intrareader reliability was excellent for both P-scores (ICC = 0.91) and A-scores (ICC = 0.93). The total P- and A-scores correlated poorly (r = 0.36) or moderately (r = 0.54), but positively, with clinical-laboratory measurements. The total MRI scores demonstrated high accuracy for discrimination of presence or absence of arthropathy [P-scale, area-under-the-curve (AUC) = 0.94 +/- 0.05; A-scale, AUC = 0.89 +/- 0.06], as did the soft tissue scores of both scales (P-scale, AUC = 0.90 +/- 0.06; A-scale, AUC = 0.86 +/- 0.06). Areas-under-the-curve used to discriminate severe disease demonstrated high accuracy for both P-MRI scores (AUC = 0.83 +/- 0.09) and A-MRI scores (AUC = 0.87 +/- 0.09), but non-diagnostic ability to discriminate mild disease. Similar results were noted for radiographic scales. In conclusion, both MRI scales demonstrated substantial to excellent reliability and accuracy for discrimination of presence/absence of arthropathy, and severe/non-severe disease, but poor to moderate convergent validity for total scores and non-diagnostic discriminant validity for mild/non-mild disease. Compared with radiographic scores, MRI scales did not perform better for discrimination of severity of arthropathy.

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.

Sonography for assessment of haemophilic arthropathy in children: a systematic protocol.

Radiological imaging of joints in children with haemophilia is important to detect abnormalities, grade their severity and monitor the effects of treatment. Scoring systems for staging haemophilic arthropathy have been developed based on plain film or magnetic resonance imaging (MRI) findings. Radiographs alone may be inadequate for evaluating joint disease in children with haemophilia on prophylaxis while MRI may be difficult to access and require the child to be sedated. Sonography can be a useful complementary modality in the evaluation of haemophilic arthropathy that is readily available and does not require the child to be sedated. In this paper, we briefly review the current imaging scales available for the assessment of haemophilic arthropathy and present a systematic protocol for sonographic assessment of the knee and ankle in haemophilic children along with examples of findings in joint effusion/hemarthrosis, synovial hypertrophy and cartilage loss. Also, we correlate the ultrasound findings with the corresponding MRI images demonstrating the anatomic planes used for imaging acquisition. Sonography is a promising technique for the assessment of soft tissue changes which are the earliest findings in haemophilic arthropathy. Further investigation is required for evaluation of osteochondral changes given limitations of sonography in this regard and in minimizing operator dependency, especially if applied in multicentric clinical trials.

Reliability and construct validity of the compatible MRI scoring system for evaluation of haemophilic knees and ankles of haemophilic children. Expert MRI working group of the international prophylaxis study group.

We tested the reliability and construct validity of the Compatible magnetic resonance imaging (MRI) scale for the evaluation of haemophilic knees and ankles and compared the diagnostic performance of MRI and plain film radiographs. Sagittal and coronal gradient-echo 1.5-T MR images of knees (n=22) and ankles (n=23) were obtained from boys (age range 4-16 years; mean 11 years) in two centres (Toronto, n=26; Europe, n=19). The MR images were independently read by four blinded radiologists on two occasions. Number of previous joint bleedings and laboratory level of severity of haemophilia were the reference standards for imaging assessment. Both components of the MRI scale demonstrated high inter- and intrareader intraclass correlation coefficients (progressive (P) scale, 0.91 and 0.94; additive (A) scale, 0.81 and 0.92 respectively). The correlation between the osteochondral domain of the MRI scale and patient's age was moderate. Otherwise, correlations between A- and P-scales and clinical laboratory measurements were weak. The areas under the curve (AUCs) used for discrimination of disease severity were similar for the A- and P-scales (AUCs used for mild disease, A-scale, 0.72+/-0.07; P-scale, 0.69+/-0.08; P=0.23; AUCs for severe disease, A-scale, 0.93+/-0.05; P-scale, 0.87+/-0.08; P=0.05). No differences were noted between the AUCs of the MRI and radiographic scales used for discrimination of late osteoarticular changes; MRI scales performed better for discrimination of early changes. In conclusion, both MRI scales demonstrated excellent reliability, poor convergent validity, and moderate and excellent validity for discrimination of mild and severe diseases respectively. Compared with radiographic scores, the MRI scales performed better for discrimination of early osteoarticular changes.

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.

Reliability of progressive and additive MRI scoring systems for evaluation of haemophilic arthropathy in children: expert MRI Working Group of the International Prophylaxis Study Group.

Effective treatment of haemophilic arthropathy requires a detailed evaluation of joint integrity. Methodological assessment of magnetic resonance imaging (MRI) scores are needed to assure reproducibility of measurements when comparing results of clinical trials conducted in different centres. We compared the reliability of two MRI scoring systems for assessment of haemophilic arthropathy: one progressive system that displays the most severe change and one additive system that depicts osteochondral and soft tissue-related changes. A total of 47 1.5 T MRI examinations of knees (n = 21) and ankles (n = 26) of 42 haemophilic boys, age range, 22 months to 18 years, performed at different centres (Toronto, n = 20, Europe, n = 12 and Denver, n = 15) were independently reviewed by four radiologists at two occasions. Twenty-two examinations were from children <9 years and 25 from children >/=9. Sagittal and coronal gradient-echo (MPGR, 3D FLASH with fat saturation, GRASS) images were obtained. The MRI examinations of the ankle and knee studies presented with osteochondral abnormalities in 38.5% and 23.8% of the cases respectively. The two scoring systems demonstrated an excellent inter-reader [progressive, 0.88; additive (A, e, s and h components), 0.86] and intra-reader [progressive, 0.92; additive (A, e, s and h components), 0.93] reliability using intraclass correlation coefficients (ICCs). Although ICCs were slightly higher for knees when compared with ankles, and for older children when compared with younger children, all values fell within excellent inter- and intra-reader reliability categories. The two MRI scoring systems demonstrated a comparable reliability. This result constitutes the basis for further development of a combined MRI scoring system for assessment of haemophilic arthropathy, which incorporates progressive and additive components.

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.

Physical therapy and imaging outcome measures in a haemophilia population treated with factor prophylaxis: current status and future directions.

Routine infusions of factor VIII to prevent bleeding, known as prophylaxis, and other intensive therapies are being more broadly applied to patients with haemophilia. These therapies differ widely in replacement product usage, cost, frequency of venous access and parental effort. In order to address residual issues relating to recommendations, implementation, and evaluations of prophylaxis therapy in persons with haemophila, a multinational working group was formed and called the International Prophylaxis Study Group (IPSG). The group was comprised of haemophilia treaters actively involved in studies of prophylaxis from North America and Europe. Two expert committees, the Physical Therapy (PT) Working Group and the Magnetic Resonance Imaging (MRI) Working Group were organized to critically assess existing tools for assessment of joint outcome. These two committees independently concluded that the WFH Physical Examination Scale (WFH PE Scale) and the WFH X-ray Scale (WFH XR Scale) were inadequately sensitive to detect early changes in joints. New scales were developed based on suggested modifications of the existing scales and called the Haemophilia Joint Health Score (HJHS) and the International MRI Scales. The new scales were piloted. Concordance was measured by the intra-class correlation coefficient of variation. Reliability of the HJHS was excellent with an inter-observer co-efficient of 0.83 and a test-retest value of 0.89. The MRI study was conducted using both Denver and European scoring approaches; inter-reader reliability using the two approaches was 0.88 and 0.87; test-retest reliability was 0.92 and 0.93. These new PT and MRI scales promise to improve outcome assessment in children on early preventive treatment regimens.

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.

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.

Local complications after limb-salvage surgery for pediatric bone tumours: a pictorial essay.

The prognosis for patients with bone sarcoma treated with LSS has improved considerably over the past 2 decades, but this has also lead to an increase in the number of complications requiring treatment. Imaging plays an important role, not only in assessing the primary tumour, but also in identifying postsurgical complications. Plain radiography demonstrates the majority of the complications associated with LSS and remains the mainstay of follow-up imaging. Complications such as fractures are common and warrant frequent plain film follow-up. Imaging with scintigraphy, MRI and CT should be tailored to the patient's clinical history, type of surgery and suspected complications. A baseline postoperative bone scan examination can be helpful for comparisons with subsequent scans for the detection of complications. Sonography should be considered if infection is suspected. Finally, tumour recurrence may be frequent enough to consider more extensive use of MRI.

The arthritis of inflammatory childhood myositis syndromes.

OBJECTIVE: Arthritis has been an associated finding in juvenile dermatomyositis (JDM), but its prevalence, course, and response to therapy has not been well described. We investigated the frequency, course, and clinical and radiographic features in a large cohort of patients with JDM. METHODS: The charts of 94 patients with idiopathic myositis (1984-99) were reviewed: 80 JDM, 3 juvenile polymyositis (JPM), 5 amyopathic JDM, and 6 overlap myositis syndromes. Compiled data included demographics, clinical features, a detailed description of the arthritis, investigations (radiographs, autoantibodies), course, and response to therapy. All radiographs were independently reviewed by a single radiologist. RESULTS: Sixty-one percent (95% CI 50-72%) of patients with JDM had arthritis. The arthritis was reported a median 4.5 mo (range -73.6 to 76.6 mo) after the JDM onset. When compared to patients with no arthritis, the occurrence of arthritis was not significantly related to sex, race, positive antinuclear antibody or rheumatoid factor, calcinosis, nodules, vasculitis, or Raynaud's phenomenon. The initial involvement was pauciarticular in 67% and polyarticular in 33%. In the pauci group, asymptomatic knee effusions were the predominant finding (n = 19, 58%), and in 18 patients may have been the result of steroid therapy. Two patients evolved from a pauci onset to a polyarticular course. All responded to therapy (corticosteroids; 47 were taking other medications) with remission of the arthritis within a median of 2.0 mo (range 0.1-64.5 mo). However, the arthritis recurred in 39% as the corticosteroids were tapered. Four patients with JDM eventually required corticosteroid wrist injections, with resolution of the arthritis. The arthritis was nonerosive in all cases. No patient with JPM had arthritis. Three of 5 patients with amyopathic JDM and 4 of 6 with overlap myositis syndrome had a nonerosive polyarthritis. CONCLUSION: Nonerosive arthritis involving the knees, wrists, elbows, and fingers is a frequent manifestation of JDM and other idiopathic childhood myositis. The arthritis is seen early in the course of JDM and often responds to treatment. However, the arthritis may recur with tapering of corticosteroids despite remission of the JDM. In a significant proportion of JDM cases, arthritis is the major sequela and may warrant further medical therapy or intraarticular corticosteroid injections.