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Dive into the research topics where Johan L. Bloem is active.

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Featured researches published by Johan L. Bloem.


Skeletal Radiology | 1985

Chondroblastoma: A clinical and radiological study of 104 cases

Johan L. Bloem; Jacob D. Mulder

The clinical and radiographic findings in 104 patients with chondroblastoma are presented. Pain was an almost constant presenting complaint, often accompanied in the case of para-articular lesions by impaired function of an adjacent joint. The majority (80%) were in long bones with a mean age of presentation of 16 years. The characteristic radiological image of these lesions was an eccentric radiolucency, having a sharply defined sclerotic margin and containing areas of calcification in approximately a third of cases. They were always related to a growth plate. Nearly half were confined to the affected epiphysis or apophysis itself, but most of the remainder had traversed the growth plate to involve also the adjacent metaphysis. The bones around the knee and the proximal ends of the humerus and femur were the sites of predilection. A minority (20%) affected flat bones and short tubular bones of the hand and foot, with a peculiar affinity for the calcaneus and talus. The mean age of presentation of these was 28 years. The radiological pattern was similar, except for a greater tendency to expand the affected bone. Complications included the formation of a secondary aneurysmal bone cyst in 16 cases (10 of them in long bones), one malignant chondroblastoma, and one fibrosarcoma developing after radiation of the original chondroblastoma.


Journal of Magnetic Resonance Imaging | 2002

Diffusion-weighted MRI in the characterization of soft-tissue tumors

Catherina S.P. van Rijswijk; Patrik Kunz; Pancras C.W. Hogendoorn; Antonie H. M. Taminiau; Joost Doornbos; Johan L. Bloem

To explore the potential of perfusion‐corrected diffusion‐weighted magnetic resonance imaging (MRI) in characterizing soft‐tissue tumors.


Skeletal Radiology | 1994

MR imaging of edema accompanying benign and malignant bone tumors

Herman M. Kroon; Johan L. Bloem; Herma C. Holscher; Henk-Jan van der Woude; Monique Reijnierse; Anthoni H. M. Taminiau

To evaluate the incidence, quantity, and presentation of intra- and extraosseous edema accompanying benign and malignant primary bone lesions, the magnetic resonance (MR) studies of 63 consecutive patients with histologically proven primary bone tumors were reviewed. MR scans were assessed for the presence and quantity of marrow and soft tissue edema and correlated with peroperative findings, resected specimens and follow-up data. The signal intensity and enhancement of tumor and edema prior to and after intravenous administration (if any) of gadolinium-labled diethylene triamine pentaacetate (Gd-DTPA) was analyzed. Marrow edema was encountered adjacent to 8 of 39 malignant tumors and 14 of 24 benign lesions. Soft tissue edema was found accompanying 28 of 39 malignancies and 10 of 24 benign disorders. On unenhanced T1-weighted MR images tumor and edema were difficult to differentiate. Tumor inhomogeneity made this differentiation easier on T2-weighted sequences. In 36 patients the contrast medium Gd-DTPA was used. Edema was present in 27 of these patients and the respective enhancement of tumor and edema could be compared. Edema always enhanced homogeneously, and in most cases it enhanced to a similar degree as or more than tumor. Marrow and, more specifically, soft tissue edema is a frequent finding adjacent to primary bone tumors. The mere presence and quantity of marrow and soft tissue edema are unreliable indicators of the biologic potential of a lesion. Unenhanced MR scans cannot always differentiate between tumor and edema, but the administration of Gd-DTPA is of assistance in differentiating tumor from edema. Awareness of marrow and/or soft tissue edema adjacent to bone lesions is of importance because edema can be a pitfall in the diagnostic work-up and staging prior to biopsy or surgery.


European Radiology | 2006

Clinical consequences of bone bruise around the knee

Patrice W. J. Vincken; Bert P. M. ter Braak; Arian R. van Erkel; Emile G. Coerkamp; Walter M. C. Mallens; Johan L. Bloem

The aim of this study is to evaluate the relation between bone bruise and (peri-)articular derangement and to assess the impact of bone bruise on presentation and short term course of knee complaints. We recorded MR abnormalities in 664 consecutive patients with sub-acute knee complaints. Patients were divided in four groups: patients with and without intra-articular knee pathology, subdivided in patients with and without bone bruise. We assessed function and symptoms at the time of MR and 6 months thereafter. Bone bruises were diagnosed in 124 of 664 patients (18.7%). Patients with bone bruise had significantly more complete ACL, lateral meniscal, MCL and LCL tears. Both with and without intra-articular pathology patients with bone bruise had a significantly poorer function at the time of MR (Noyes score of, respectively, 313.21 versus 344.81 and 306.98 versus 341.19). Patients with bone bruise and intra-articular pathology showed significantly more decrease in activity (decrease of Tegner score from 6.28 to 2.12 versus 5.70–2.55). At 6 months there were no significant differences in clinical parameters between the four groups. We concluded that bone bruise in combination with MCL tear is an important cause of initial clinical impairment in patients with sub-acute knee complaints. Clinical improvement within 6 months is more pronounced than in patients without bone bruise.


Annals of the Rheumatic Diseases | 2015

Characterising arthralgia in the preclinical phase of rheumatoid arthritis using MRI

Hanna W. van Steenbergen; Jessica A. B. van Nies; Tom W J Huizinga; Johan L. Bloem; Monique Reijnierse; Annette H. M. van der Helm-van Mil

Background The phase of arthralgia is the earliest moment to clinically recognize patients who may develop Rheumatoid Arthritis (RA). Previous imaging studies in the arthralgia phase have shown that inflammation precedes RA development. It is unknown which symptoms/characteristics relate to subclinical joint inflammation as measured by MRI. Among all patients with arthralgia, those with clinically suspect arthralgia (CSA) are suspected to progress to arthritis according to the clinical judgement of their rheumatologists. We determined the symptoms/characteristics of patients with CSA who had inflammation on MRI. Methods 102 patients with CSA and without clinical arthritis were included. They completed questionnaires, underwent joint counts and unilateral 1.5 T MRI of MCP joints 2–4, wrist and MTP joints 1–5. Synovitis, bone marrow oedema (BME) and tenosynovitis were scored according to the OMERACT rheumatoid arthritis MRI scoring system. Symptoms and signs were related to MRI inflammation (based on MRI scores in symptom-free controls; a sum of synovitis, BME and tenosynovitis scores ≥3 was considered positive). Whether certain clinical characteristics frequently occurred together with MRI inflammation was studied by partial least squares analysis. Results MRI was performed in 93 patients with CSA, 44% of whom had subclinical MRI inflammation. Synovitis was the most prevalent inflammatory feature on MRI (20%). Patients with MRI inflammation were older and were more frequently positive for anti-citrullinated peptide antibodies than patients without MRI inflammation (p<0.001 and 0.049). In PLS analysis, including 16 clinical and serological characteristics as independent variables and MRI inflammation as dependent variable, no clear clusters of patients with and without MRI inflammation were identified. Conclusions Subclinical inflammation as measured by MRI is present in 44% of patients with CSA. A combination of symptoms/characteristics incompletely differentiated patients with and without MRI inflammation.


Journal of Magnetic Resonance Imaging | 2004

Magnetic resonance imaging of knee cartilage using a water selective balanced steady-state free precession sequence†

Peter R. Kornaat; Joost Doornbos; Aart J. van der Molen; Margreet Kloppenburg; Rob G. H. H. Nelissen; Pancras C.W. Hogendoorn; Johan L. Bloem

To compare an optimized water selective balanced steady‐state free precession sequence (WS‐bSSFP) with conventional magnetic resonance (MR) sequences in imaging cartilage of osteoarthritic knees.


Annals of the Rheumatic Diseases | 1990

Magnetic resonance imaging of the shoulder in patients with rheumatoid arthritis.

G. J. Kieft; Ben A. C. Dijkmans; Johan L. Bloem; Herman M. Kroon

To evaluate the ability of magnetic resonance imaging (MRI) to detect shoulder abnormalities 18 patients (36 shoulders) with rheumatoid arthritis (RA) and shoulder complaints were studied. Osseous abnormalities of the glenoid and humeral head were readily detected with MRI. The imaging planes used were not suitable for the evaluation of acromioclavicular joint involvement. Magnetic resonance imaging depicted soft tissue abnormalities that were not clearly visualised by plain film radiography, such as involvement of rotator cuff tendons and subacromial bursae, joint effusion, and muscular atrophy. Magnetic resonance imaging appears to be a sensitive method for evaluation of glenohumeral joint changes in patients with RA.


European Radiology | 2003

Dynamic contrast-enhanced MR imaging in monitoring response to isolated limb perfusion in high-grade soft tissue sarcoma: initial results

Catherina S.P. van Rijswijk; Maartje J. A. Geirnaerdt; Pancras C.W. Hogendoorn; Johannes L. Peterse; Frits van Coevorden; Antonie H. M. Taminiau; Rob A. E. M. Tollenaar; Bin B. R. Kroon; Johan L. Bloem

The objective of this study was to evaluate whether dynamic contrast-enhanced MR imaging can determine tumor response and localize residual viable tumor after isolated limb perfusion (ILP) chemotherapy in soft tissue tumors. Twelve consecutive patients, with histologically proven high-grade soft tissue sarcoma, prospectively underwent non-enhanced MR and dynamic contrast-enhanced MR imaging before and after ILP. Tumor volume was measured on non-enhanced MR images. The temporal change of signal intensity in a region of interest on dynamic contrast-enhanced MR images was plotted against time. Start, pattern, and progression of enhancement were recorded. Histopathologic response was defined as complete response if no residual viable tumor was present, partial remission if <50% viable tumor was present, and no change if ≥50% viable tumor was present in the resection specimen. Resected specimens for correlation with histopathology were available for 10 patients; 5 patients had partial remission and 5 had no change. Volume measurements correctly predicted tumor response in 6 of 10 patients. Dynamic contrast-enhanced MR correctly predicted tumor response in 8 of 10 patients. Early rapidly progressive enhancement correlated histologically with residual viable tumor. Late and gradual, or absence of enhancement, was associated with necrosis, predominantly centrally located, or granulation tissue. These preliminary results show that dynamic contrast-enhanced MR imaging offers potential for non-invasive monitoring of response to isolated limb perfusion in soft tissue sarcomas due to identification of residual areas of viable tumor and subsequently may provide clinically useful information with regards to timing and planning of additional surgery. Further prospective studies in a larger patient population is warranted.


Annals of the Rheumatic Diseases | 2013

MRI of hand and foot joints of patients with anticitrullinated peptide antibody positive arthralgia without clinical arthritis

A. Krabben; Wouter Stomp; Désirée van der Heijde; Jessica A. B. van Nies; Johan L. Bloem; Tom W J Huizinga; Monique Reijnierse; Annette H. M. van der Helm-van Mil

Background Anticitrullinated peptide antibodies (ACPA) and acute phase reactants may be increased before arthritis becomes clinically detectable, suggesting that the processes underlying rheumatoid arthritis (RA) start preclinically. Whether local inflammation occurs in the preclinical phase is unknown. Therefore, we studied the small joints of ACPA positive arthralgia patients for local subclinical inflammation. Methods Imaging was performed using 1.5 T extremity MRI. Painful hand or foot joints of 21 ACPA positive arthralgia patients without clinical arthritis were imaged. For comparison, hand and foot joints of 22 ACPA positive RA patients and 19 symptom free controls were studied. Within ACPA positive arthralgia patients, painful and symptom free joint regions were imaged. Scoring was performed according to the Outcome Measures in Rheumatology Clinical Trials (OMERACT) Rheumatoid Arthritis Magnetic Resonance Imaging Scoring (RAMRIS) method. Analyses were performed on joint region level and focused on inflammation (synovitis plus bone marrow oedema). Results The mean combined inflammation scores of the metacarpophalangeal/proximal interphalangeal joints of controls, painful joints of ACPA positive arthralgia patients and ACPA positive RA patients were 0.1, 0.7 and 3.7, respectively (p<0.001). Likewise, the mean combined inflammation scores of the wrist were 0.9, 2.3 and 10.3, respectively (p<0.001) and that of the metatarsophalangeal joints 0.5, 0.9 and 3.8, respectively (p=0.10). At the MCP joints, the combined inflammation score was significantly correlated with C reactive protein and erythrocyte sedimentation rate levels (rs=0.83 and rs=0.78, respectively) Conclusions The present data suggest that local subclinical inflammation occurs in ACPA positive arthralgia patients.


Skeletal Radiology | 1996

The cervical spine in rheumatoid arthritis: relationship between neurologic signs and morphology on MR imaging and radiographs

Monique Reijnierse; Johan L. Bloem; Ben A. C. Dijkmans; Herman M. Kroon; Herma C. Holscher; Bettina Hansen; Ferdinand C. Breedveld

Abstract Objective. Comparison of clinically observed neurologic long tract signs in a heterogeneous group of patients with rheumatoid arthritis (RA), with morphologic abnormalities of the cervical spine as depicted on radiographs and magnetic resonance (MR) images. Design. The patients were prospectively assigned to one of three classes on the basis of their neurologic status. Lateral cervical spine radiographs and sagittal T1-weighted and gradient echo images were performed. The qualitative MR features evaluated were erosion of the dens and atlas, brain stem compression, subarachnoid space encroachment, pannus around the dens, appearance of the fat body caudal to the clivus, and the signal intensity of the pannus. The quantitative imaging parameters were the cervicomedullary angle and the distance of the dens to the line of McRae. Patients. Sixty-three consecutive patients with RA and subjective symptoms, especially neck or occipital pain, and/or clinical objective signs consistent with a compromised cervical cord were included in this study. Results and conclusions. Damage documented with radiographs and MR imaging in patients with RA is often severe, even in those without neurologic signs (class 1). None of the abnormalities confined to the atlantoaxial level correlated significantly with neurologic classification. Subarachnoid space encroachment anywhere in the entire cervical spine did correlate significantly with neurologic classification.

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Monique Reijnierse

Leiden University Medical Center

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Margreet Kloppenburg

Leiden University Medical Center

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Herman M. Kroon

Leiden University Medical Center

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Pancras C.W. Hogendoorn

Leiden University Medical Center

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Tom W J Huizinga

Leiden University Medical Center

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Arian R. van Erkel

Leiden University Medical Center

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Henk-Jan van der Woude

Leiden University Medical Center

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Désirée van der Heijde

Leiden University Medical Center

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Peter R. Kornaat

Leiden University Medical Center

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