PubMed Health⌕ Search

Biomedical subjects

B Lundin

Publications and source records attributed to B Lundin.

At least 19 recordsLinked to original sources
PubMed2006

Evolution of the imaging tests in hemophilia with emphasis on radiography and magnetic resonance imaging.

Even before the discovery of X-rays in 1895 attempts were being made to classify the joint destruction that occurs in hemophilic arthropathy. The advent of radiography added impetus to the search for the optimum classification system. Subsequent attempts have included advanced imaging methods, especially magnetic resonance imaging (MRI). Because of its high spatial resolution and ability to visualize soft tissue abnormalities, MRI is ideally suited as the best way to classify arthropathy. A literature search was carried out to document and list all the imaging methods for hemophilic arthropathy that have been published up to the present. All published classification systems are discussed and listed in tables. MRI has superior imaging capability and will probably become the most important modality for radiological classification of hemophilic arthropathy in the future.

Arthrography↗
PubMed2006

Recent developments in clinimetric instruments.

Assessment of impairment and function is essential in order to monitor joint status and evaluate therapeutic interventions in patients with haemophilia. The improvements in the treatment of haemophilia have required the development of more sensitive tools to detect the more minor dysfunctions that may now be apparent. This paper outlines some of the recent developments in this field. The Haemophilia Joint Health Score (HJHS) provides a systematic and robust measure of joint impairment. The MRI Scoring System has been designed to provide a comprehensive scoring system combining both progressive and additive scales. The Functional Independence Score for Haemophilia (FISH) has been developed to assess performance of functional activities and can be used in conjunction with the Haemophilia Activities List (HAL) which provides a self report measure of function. It is recommended that both measures are evaluated as these tools measure different constructs. Further refinement and testing of the psychometric properties of all of these tools is in progress. More widespread use of these tools will enable the sharing of data across the world so promoting best practice and ultimately enhancing patient care.

Activities of Daily Living↗
PubMed2006

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.

Adolescent↗
PubMed2005

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.

Cartilage, Articular↗
PubMed2005

MRI scores of ankle joints in children with haemophilia--comparison with clinical data.

Fifty-six ankle joints in 38 haemophilic boys were investigated by magnetic resonance imaging (MRI) and the findings were classified according to both the Denver- and the European scoring schemes. The different MRI scores were compared with each other and with clinical data on number of joint bleeds and the orthopaedic joint score. MRI changes that were more advanced than a small effusion were found in 33 (59%) of the ankles and osteochondral changes were observed in 20 (36%). The total number of bleeds in individual ankles ranged from 0 to 80 (mean: 11). The orthopaedic joint score was 0 for 49 ankles and ranged from one to four for seven ankles. There was a significant and strong correlation between the assessment results obtained with the two MRI scoring methods (correlation coefficients ranged from 0.80 to 0.95, P < 0.001), and both types of MRI scores were weakly but significantly correlated with the clinical data on the number of joint bleeds and the orthopaedic joint score (correlation coefficients: 0.32-0.39, P < 0.01 or P < 0.05). MRI is useful for evaluating early joint changes in patients with haemophilia. The European scoring method differentiates the arthropathic changes further than the Denver scale does, but the two different scoring methods have similar correlation to the number of joint bleeds and the orthopaedic joint score.

Adolescent↗
PubMed2005

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.

Adolescent↗
PubMed2004

A new magnetic resonance imaging scoring method for assessment of haemophilic arthropathy.

In a European multicentre study, 39 ankles in 28 haemophilic boys were investigated by magnetic resonance imaging (MRI). A new MRI score was developed in the format A(e:s:h) for evaluating haemophilic arthropathy. This scheme provides high resolution and allows separation of different pathological components. The factor A is calculated as the sum of scores for subchondral cysts (maximum value 6), irregularity/erosion of subchondral cortex (maximum 4) and chondral destruction (maximum 6); e, s and h, respectively, represent effusion/haemarthrosis, synovial hypertrophy and haemosiderin deposition, and they are separately evaluated on a scale of 0-4. Working independently, two radiologists scored the 39 ankles twice using both this new 'European' scoring method and a previously published 'Denver' scoring scheme. Final classification was achieved by consensus. The reproducibility of the readings was assessed, and for both scoring methods the results indicated good or moderate intraobserver agreement, and good, moderate or fair interobserver agreement. These findings suggest that MRI can be useful for semiquantitative evaluation of haemophilic arthropathy, providing the examination is performed according to an appropriate protocol, and the images are evaluated by specially trained radiologists.

Ankle Joint↗
PubMed2004

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.

Hemophilia A↗
PubMed2003

Are digital images good enough? A comparative study of conventional film-screen vs digital radiographs on printed images of total hip replacement.

The aim of this study was to evaluate the inter- and intra-observer variability and to find differences in diagnostic safety between digital and analog technique in diagnostic zones around hip prostheses. In 80 patients who had had a total hip replacement (THR) for more than 2 years, a conventional image and a digital image were taken. Gruen's model of seven distinct regions of interest was used for evaluations. Five experienced radiologists observed the seven regions and noted in a protocol the following distances: stem-cement; cement-bone; and stem-bone. All images were printed on hard copies and were read twice. Weighted kappa, kappa(w), analyses were used. The two most frequently loosening regions, stem-cement region 1 and cement-bone region 7, were closely analyzed. In region 1 the five observers had an agreement of 86.75-97.92% between analog and digital images in stem-cement, which is a varied kappa(w) 0.29-0.71. For cement-bone region 7 an agreement of 87.21-90.45% was found, which is a varied kappa(w) of 0.48-0.58. All the kappa values differ significantly from nil. The result shows that digital technique is as good as analog radiographs for diagnosing possible loosening of hip prostheses.

Arthroplasty, Replacement, Hip↗
PubMed2001

[Munchausen syndrome by proxy. Child abuse by falsification of symptoms].

Münchausen syndrome by proxy (MSbP) is a potentially lethal form of child abuse. Mortality rates around 10 percent have been reported. A knowledge of the characteristics of MSbP is needed in order to reveal the diagnosis and to handle the management correctly. Swedish experience is in accordance with international reports.

Adult↗
PubMed1996

Passive knee muscle moment arms measured in vivo with MRI.

OBJECTIVE: To determine moment arm lengths from seven knee muscles and the patellar tendon. The knee muscles were the biceps femoris, semitendinosus, semimembranosus, gracilis, sartorius, and the lateral and medial gastrocnemius muscles. DESIGN: The moment arms were calculated based on MRI measurements. BACKGROUND: Moment arm lengths of different muscles with respect to the joint centre of rotation (CR) or the centre of the contact point between joint surfaces are necessary basic data for biomechanical models predicting joint load. METHODS: Ten male and seven female subjects participated. Using a 1.5 Tesla magnetic resonance imaging system, 3-dimensional coordinates of relevant points were recorded from a 3-D volume reconstruction of the right knee at knee flexion angles of 0, 30 and 60 degrees. Muscular moment arms were calculated in both the sagittal and frontal planes. The recordings were all made during passive mode, which means that no muscular contraction was performed. RESULTS: All muscles except the lateral gastrocnemius showed statistically significant differences (P<0.05) of moment arm lengths between gender in the frontal plane. All muscles except biceps femoris and sartorius showed significant differences (P<0.05) of moment arm lengths between gender in the sagittal plane. Most muscles also showed a linear or quadratic trend of changing moment arms with varying knee angle. CONCLUSIONS: Our results indicate that for most biomechanical analyses involving knee muscles, gender- and angle-specific moment arms should be used.

Journal Article↗
PubMed1996

Radiation dose reduction in computed skeletal radiography. Effect on image quality.

PURPOSE: To evaluate the effect of radiation dose reduction on image ++quality in computed musculoskeletal radiography and determine optimal exposure range. MATERIAL AND METHODS: In 11 corpses, 1 hand and 1 hip were examined with film-screen radiography, and a series of computed radiographs was obtained using exactly the same technique except for the exposure, which was 100, 50, 25, 12.5, 6.25, and 1.56% of the mAs numbers used for the film-screen images. The computed hip radiographs were processed in 2 different ways, one simulating the film-screen images and one using contrast enhancement. Four radiologists reviewed the images regarding the following parameters: cortical bone, trabecular bone, joint space, and soft tissue, giving each a diagnostic quality rating on a scale from 1 to 5. The median and mean values were found for the pooled results. RESULTS: For the hands, the computed radiographs were ranked inferior to the film-screen images for all parameters except soft tissue, where the computed radiographs scored higher. The computed images with 50 and 25% exposure were ranked equal to the 100% ones. The quality rating slowly declined with lower exposures. For the hips, the 100 and 50% computed radiographs were generally similar to or slightly better than the film-screen images. The decline was somewhat faster than for the hands. The contrast-enhanced hip images scored less than the nonenhanced images at any given exposure for all parameters except soft tissue, where the contrast-enhanced images scored better at all exposures. The difference between nonenhanced and enhanced images became less at the lower exposures. CONCLUSION: Lowering the exposure in computed musculoskeletal radioagrphy below the level of film-screen radiography is feasible, especially in the peripheral skeleton. Contrast enhancement seems to be valuable only in the evaluation of soft-tissue structures.

Bone and Bones↗
PubMed1995

Preschoolers' sexual behavior at daycare centers: an epidemiological study.

The frequency of sexual behaviors in a population of preschoolers (n = 251) attending Swedish daycare centers was studied using a questionnaire given to the staff. Some behaviors turned out to be frequently occurring, like searching for body contact and responding to such contact. However, several behaviors were very uncommon (1% or fewer): touching an adult's genitals; attempting to make the adult touch the child's genitals; using objects against own or other child's genitals/anus; to masturbate obsessively, without pleasure or in a way that caused pain. Other behaviors occurred more frequently but were still uncommon (less than 2% of the children displayed such a behavior "sometimes" or "often/daily"): exhibiting own genitals; playing sexually explorative games; initiating games with a similarity to adult sexual activity; using sexual words; attempting to touch a woman's breast. Only masturbation and clinging body contact were positively correlated with behavioral disturbance. The correlations between age and single behaviors may be summarized as manifestations of the process of socialization. The results offer an incipient frame of reference for statistically normal expected sexual behaviors in preschoolers at daycare centers. The rarity of certain behaviors implies that their occurrence in an individual case may necessitate special clinical attention.

Child↗
PubMed1993

Sustained 5-hydroxytryptamine release-inhibitory and anxiolytic-like action of the partial 5-HT1A receptor agonist, buspirone, after prolonged chronic administration.

The effect of prolonged administration of high doses of buspirone on its 5-hydroxytryptamine (5-HT) release-inhibitory and anxiolytic-like properties was investigated. The 5-HT release-inhibitory effect of a challenge dose of buspirone (0.5 mg/kg, s.c.) was identical in rats chronically treated with vehicle or buspirone (10 mg/kg, b.i.d. for 10 weeks), as estimated by in vivo microdialysis in the ventral hippocampus. In the same set of animals there was a significant anxiolytic-like effect in the elevated plus-maze after 5 weeks of treatment with buspirone. The results indicate that the functional capacity of 5-HT release-controlling 5-HT1A autoreceptors is retained upon chronic administration of buspirone, and that this effect may well be associated with the anxiolytic-like action of the compound.

Animals↗
PubMed1993

Measurement of total and unilateral renal blood flow by oblique-angle velocity-encoded 2D-cine magnetic resonance angiography.

Two independent measurements of total renal blood flow (RBF) were made in healthy human subjects (n = 14, mean age 30 yr) by CINE phase-contrast magnetic resonance angiography. RBF, measured by summing the flows measured in the right and left renal arteries, was 1152 +/- 44 ml/min (mean +/- SE). RBF, measured from the difference between supra- and infrarenal abdominal aorta flow, was 1109 +/- 68 ml/min. Regression analysis of the comparison of these two different RBF calculations yielded a correlation coefficient of 0.72 at a p < .05 level of significance. Based on other studies of RBF in normal subjects by para-aminohippuric acid (PAH) clearance, the expected RBF in this subject group was 1211 +/- 62 ml/min. The results indicate that noninvasive measurement of RBF is possible using phase-contrast magnetic resonance methods.

Adolescent↗