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M De Maeseneer

Publications and source records attributed to M De Maeseneer.

At least 19 recordsLinked to original sources

Popliteal cysts in children: prevalence, appearance and associated findings at MR imaging.

OBJECTIVE: The purpose of this study was to determine the prevalence of Baker's cysts on MR images in a paediatric orthopaedic population, to investigate the association of Baker's cyst with joint fluid and joint disorders in children, and to compare the MR appearance of Baker's cysts in children with that previously reported in adults. MATERIALS AND METHODS: Reports from 393 MR studies of the knee performed in children aged from 1 to 17 years were retrospectively reviewed for the presence of a Baker's cyst, joint effusion, meniscal tear, anterior cruciate ligament tear, or any other joint disorder. RESULTS: A Baker's cyst was identified in 6.3 % (25/393) of patients. The MR images and clinical charts of patients with a Baker's cyst were reviewed. None of the 25 patients with a Baker's cyst had an associated anterior cruciate ligament tear or meniscal tear. Two patients had osteochondritis dissecans and two others had synovial disease (infection and juvenile rheumatoid arthritis). Joint fluid was demonstrated in 16 % (4/25) of patients with a Baker's cyst. There was no statistically significant association between presence of a Baker's cyst and presence of joint fluid. CONCLUSIONS: Baker's cyst is less prevalent in a paediatric orthopaedic population than in an adult population. In children, it seems that Baker's cyst is seldom associated with joint fluid, meniscal tear, or anterior cruciate ligament tear. On MR images, a communication between the Baker's cyst and the joint was not demonstrated in any of the patients. In addition, the presence of debris and cyst leakage was not observed.

Adolescent

Subperiosteal ganglion cyst of the tibia. A communication with the knee demonstrated by delayed arthrography.

We report a patient with a subperiosteal ganglion cyst of the tibia which was imaged by radiography, arthrography, CT and MRI. The images were correlated with the arthroscopic surgical and histological findings. Spiculated formation of periosteal new bone on plain radiographs led to the initial suspicion of a malignant tumour. Demonstration of the cystic nature of the tumour using cross-sectional imaging was important for the precise diagnosis. Communication between the ganglion cyst and the knee was shown by a delayed arthrographic technique, and the presence of this communication was confirmed at arthroscopy and surgically.

Arthrography

Subcutaneous granuloma annulare: MR imaging findings.

We present a case of subcutaneous granuloma annulare evaluated with MR imaging. The mass was poorly defined and showed thickened interconnecting strands with low signal intensity on T1- and T2-weighted MR images. When a poorly defined subcutaneous mass with low signal intensity on both T1- and T2-weighted MR images is observed in an otherwise healthy child, subcutaneous granuloma annulare should receive serious consideration. Subcutaneous granuloma annulare should be added to the list of tumors with short T2.

Buttocks

Deep benign fibrous histiocytoma of the knee: CT and MR features with pathologic correlation.

Magnetic resonance imaging and pathologic findings in a 28-year-old patient with a giant deep benign fibrous histiocytoma in the popliteal fossa of the right knee are described. The MR imaging findings include a well-delineated oval mass with low signal intensity on T1-, and high signal intensity on T2-weighted, images, and marked peripheral contrast enhancement. To the best of our knowledge, this is the first report on the MR findings in this entity.

Adult

Otodental syndrome. A case report.

A 12-year-old boy with characteristic findings of otodental syndrome is presented. Abnormalities of deciduous and permanent dentition included bulbous canines, globe-shaped posterior teeth and agenesis of maxillary premolars. High-frequency sensorineural hearing loss was demonstrated, and results of genetic studies indicated an autosomal dominant trait. This patient presented previously unreported findings, including generalized macrodontia, delayed mineralization of the mandibular premolars, and supplementary permanent maxillary canines.

Child

Elbow effusions: distribution of joint fluid with flexion and extension and imaging implications.

RATIONALE AND OBJECTIVES: The authors study the distribution of elbow joint fluid with flexion and extension of the joint and evaluate the imaging implications of such distribution. METHODS: Three cadaveric elbows were studied with radiography, ultrasonography, and magnetic resonance imaging after the incremental injections of 1 to 15 mL of saline solution into the elbow joint. Imaging was obtained with full flexion and extension of the joint. Anatomic sections were obtained for correlation. RESULTS: In flexion fluid initially collected posteriorly and, with larger quantities, anteriorly. In extension the anterior fat pad was pressed into its fossa and the posterior fat pad was displaced superiorly by the olecranon process. On lateral radiographs in elbow flexion a positive fat pad sign was seen with 5 to 10 mL of fluid in the joint. Sonography allowed identification of 1 to 3 mL of fluid posteriorly with the elbow flexed. Magnetic resonance imaging allowed identification of 1 mL of fluid, regardless of joint position and location. CONCLUSIONS: The distribution of joint fluid in the elbow is influenced by flexion and extension of the joint. Radiography is best performed in flexion. Sonography is more sensitive than radiography in diagnosing effusions, but should be performed along the olecranon fossa with the elbow flexed. Magnetic resonance imaging is most sensitive in identifying effusions, regardless of joint position or location.

Body Fluids

Detection of ankle effusions: comparison study in cadavers using radiography, sonography, and MR imaging.

OBJECTIVE: The purpose of this study was to compare radiography, sonography, and MR imaging in revealing ankle effusions in cadaveric specimens. MATERIALS AND METHODS: Known quantities of saline solution were instilled in increments into the ankle joints of three cadaveric specimens. Imaging was completed after each injection with the ankle in dorsiflexion, plantar flexion, and a neutral position. Imaging included radiography, sonography, and MR imaging. Three observers who were aware of possible joint fluid evaluated the images by consensus and determined the presence or absence of joint effusion. RESULTS: MR imaging revealed 1 ml of fluid within the anterior recess of the ankle in a neutral position and in plantar flexion and within the posterior recess in dorsiflexion. Sonography revealed 2 ml of fluid within the anterior recess in a neutral position and in plantar flexion. Radiography revealed 5 ml of fluid within the anterior recess in a neutral position. CONCLUSION: MR imaging, sonography, and lateral radiography, in order of decreasing sensitivity, revealed ankle effusion. The power to reveal with each technique is influenced by the precise position of the ankle.

Adipose Tissue

Normal and abnormal medial meniscocapsular structures: MR imaging and sonography in cadavers.

OBJECTIVE: The purpose of this study was to develop imaging criteria for the diagnosis of meniscocapsular separation by correlating findings on MR imaging, MR arthrography, and sonography of normal and abnormal medial meniscocapsular structures with corresponding anatomic sections in cadavers. MATERIALS AND METHODS: Eight cadaveric knee specimens were examined with MR imaging, MR arthrography, and sonography before arthroscopy. In six specimens the following lesions were arthroscopically created: meniscocapsular separation (n = 3), medial collateral ligament (MCL) tear (n = 3), tear of the meniscofemoral extension of the deep MCL (n = 2), and coronary ligament tear (n = 2). After arthroscopy, all imaging studies were repeated. The specimens were sectioned for correlation with imaging studies. RESULTS: MR findings that correlated with meniscocapsular separation were interposition of fluid between the meniscus and the MCL, irregular meniscal outline, and increased distance between the meniscus and the MCL. On MR arthrography meniscocapsular separation correlated with interposition of contrast medium between the meniscus and the MCL. Tears of the meniscofemoral extension of the deep MCL were best shown on MR arthrography. Sonography showed deep and superficial MCL lesions but did not show meniscocapsular separations. CONCLUSION: In arthroscopically created meniscocapsular separation, the lesion is suggested on MR images when fluid is interposed between the meniscus and the MCL, when the meniscal outline is irregular, or when the distance between the meniscus and the MCL is increased. On MR arthrograms, a meniscocapsular separation is suggested when contrast medium is interposed between the meniscus and the MCL. Sonography does not allow accurate diagnosis of meniscocapsular separation.

Cadaver

MRI of extrapancreatic gastrinomas.

Preoperative diagnosis of gastrinoma--especially extrapancreatic gastrinoma--is very difficult. At the moment octreotide scintigraphy is considered the method of choice to detect gastrinomas. However, MRI may play a major role in the diagnostic imaging of gastrinoma.

Contrast Media

Calcium hydroxyapatite deposition disease of the neck: finding in three patients.

Calcium hydroxyapatite deposition disease may occasionally involve the superolateral portion of the longus colli muscle. Clinical symptoms include headache, neck pain, and dysphagia. Characteristic prevertebral calcifications with the epicenter at the C1-C2 level are depicted on lateral radiographs of the cervical spine.

Adult

Glenoid dysplasia: radiographic and CT arthrographic findings.

A 60-year-old man with dysplasia of the glenoid and a rotator cuff tear is reported on. Because of the tear, CT arthrography was performed, offering an opportunity to evaluate the various soft tissue abnormalities accompanying glenoid dysplasia. Marked thickening of the glenoid cartilage and labrum was apparent, as well as an abnormal posterolateral orientation of the glenoid cavity. A deep notch was observed along the central portion of the glenoid cartilage. Furthermore the middle glenohumeral ligament appeared thickened and cordlike.

Arthrography

Calcific tendinitis of the longus colli muscle.

BACKGROUND: To the best of our knowledge, only one patient with calcium hydroxyapatite deposition disease (CHADD) of the longus colli muscle has been reported in the otolaryngology literature. METHODS: Clinical findings and results of imaging studies in such a patient are reported. RESULTS: Two particular imaging findings of this disorder are discussed. First, disappearance of calcifications over the short time frame of a week, accompanied by the resolution of clinical symptoms. Second, the presence of an extensive region of high signal intensity extending from the skull base to the lower border of C5, on T2-weighted spin-echo magnetic resonance (MR) images. CONCLUSIONS: Knowledge of the characteristic clinical spectrum and imaging features of this disorder are crucial for a correct diagnosis of this uncommon cause of odynophagia and dysphagia.

Calcinosis

Influence of spondylopathy on bone densitometry using dual energy X-ray absorptiometry.

Spinal cord injury (SCI), as well as other neuromuscular disorders, not only results in osteopenia but also induces various patterns of osseous, articular, and soft tissue alterations. In the spinal column, a variety of abnormalities occur. To evaluate the magnitude of discrepancy of bone densitometry results caused by spondylopathy in SCI patients, we analyzed anteroposterior (AP) radiographs of the lumbar spine [obtained within 1 month of dual energy X-ray absorptiometry (DXA)] in 116 SCI patients for various manifestations of spondylopathy, and matched the result to each vertebral level (L1, 2, 3, 4). The dataset was stratified by individual vertebra (totally 463 vertebrae) as valid (no demonstrable other abnormal density on plain radiograph except osteopenia), abnormal without, and abnormal with hardware. The influence of spondylopathy on bone densitometry results was determined by the analysis of variance (ANOVA) and post hoc analysis. Our results showed that 227 (49%) vertebrae were abnormal. Significant elevation (15%, 15%, 18%, 20%; P < 0.001-P < 0.05) of bone mineral density (BMD; g/cm2) was observed at all levels (L1, 2, 3, 4, respectively), particularly at those abnormal vertebrae without hardware compared with valid (no other abnormal density on radiograph except osteopenia (Table 1). The L4 level was most severely affected. We concluded that in SCI patients, owing to various secondary progressive skeletal abnormalities, particularly neuropathic spondylopathy, can have strongly and significantly elevated vertebral bone densitometry results, which can obscure underlying osteoporosis, leading to misinterpretation and underestimation of fracture risk. DXA, although characterized by improving spatial resolution, cannot replace radiography in establishing the magnitude of this skeletal pathology. Therefore, determination of bone density in this region with corresponding plain radiographs is highly recommended.

Absorptiometry, Photon

Fibrolipomatous hamartoma: MR imaging findings.

OBJECTIVE: To analyze the MR imaging features of fibrolipomatous hamartoma (FLH) of nerves. DESIGN AND PATIENTS: MR imaging studies from six patients (three men and three women) were retrospectively reviewed by three musculoskeletal radiologists. In four patients, a biopsy of the nerve lesion was performed. In two patients, biopsy data were unavailable and the diagnosis was based on the clinical history combined with the MR imaging findings. RESULTS AND CONCLUSION: MR imaging demonstrated fusiform nerve enlargement that was caused by fatty proliferation and thickening of nerve bundles. Nerve bundles appeared as serpentine tubular structures, hypointense on both T1- and T2-weighted images. The degree of fatty proliferation varied among patients. In addition, significant variation in the distribution of fat along the course of the nerves was noted. In three patients, FLH followed the branching pattern of the nerves, a characteristic pathologic finding. In two patients, intramuscular fat deposition (biceps and tibialis posterior muscles) was present. MR imaging findings of FLH are typical, allowing a confident diagnosis. The variation of fatty proliferation among patients and involved nerves as well as the tendency of the abnormalities to follow the branching pattern of the nerves is well demonstrated with MR imaging. FLH may present as an isolated nerve lesion, may be associated with intramuscular fat deposition, or may occur as a feature of macrodystrophia lipomatosa (MDL).

Adult

Evolving stages of lipohemarthrosis of the knee. Sequential magnetic resonance imaging findings in cadavers with clinical correlation.

RATIONALE AND OBJECTIVES: Lipohemarthrosis, the presence of fat and blood in a joint cavity, exhibits several complex layers related to differences in specific component relaxation on magnetic resonance (MR) images. The authors investigated sequential changes in the appearance of lipohemarthrosis of the knee as demonstrated by MR imaging. METHODS: Sequential MR imaging over a 4-day period was performed on two cadaveric knees after intraarticular injection of blood from a volunteer and fat from a cadaveric tibia (50 mL of blood and 25 mL of fat in one knee and 15 mL of blood and 5 mL of fat in the other knee). The authors determined components in the joint based on MR signal behavior. Magnetic resonance imaging examinations of four patients with intracapsular fractures and lipohemarthroses of the knee were reviewed retrospectively. RESULTS: Sequential MR images of cadaveric knees showed serial changes representing progressive formation and lysis of blood clot. Several fluid-fluid levels (globules of fat at the interface between fat and blood) and entrapment of fat were early findings of lipohemarthrosis. Three different fluid levels appeared approximately 3 hours after injection of fresh blood and marrow fat. The 96-hour study demonstrated three distinct levels. CONCLUSIONS: Lipohemarthrosis demonstrates temporal changes on MR imaging related to stages of formation and lysis of blood clot.

Adult