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R Dussault

Publications and source records attributed to R Dussault.

18 recordsLinked to original sources

Arachnoiditis ossificans: MR imaging features in five patients.

OBJECTIVE: The purpose of this article is to illustrate the appearance of arachnoiditis ossificans on MR imaging and discuss the implications this diagnosis has on treatment. CONCLUSION: In patients with arachnoiditis ossificans, the MR imaging findings are of linear or masslike intrathecal lesions, which generally have some hyperintensity on T1- weighted sequences and are hyper- or hypointense on T2-weighted images, in the setting of arachnoiditis.

Adult↗

Age-related marrow conversion in the proximal metaphysis of the femur: evaluation with T1-weighted MR imaging.

PURPOSE: To determine the normal chronologic changes in fatty marrow conversion of the proximal femoral metaphysis at magnetic resonance (MR) imaging. MATERIALS AND METHODS: The "marrow conversion index," (signal intensity of the proximal femoral metaphysis divided by signal intensity of the greater trochanter) x 100, was measured in 182 hips of 91 patients who had no evidence of osteonecrosis or diseases involving bone marrow, no history of steroid treatment, and no other risk factors for osteonecrosis. The results were evaluated according to patient age and sex. RESULTS: The index showed a progressive linear increase with age regardless of sex. The index was 65.4% +/- 5.6 (standard deviation) in patients aged 15-19 years and increased monotonously with age to 87.5% +/- 7.0 in patients aged 60-79 years. Simple linear regression of the index according to age group showed that the marrow conversion index is roughly equal to 63 + 4 x Z (p < .001), where Z is 1.5 for patients aged 15-19 years, 2.0 for patients aged 20-29 years, 3.0 for patients aged 30-39 years, 4.0 for patients aged 40-49 years, 5.0 for patients aged 50-59 years, and 6.0 for patients aged 60-79 years. CONCLUSION: There is a linear association of marrow conversion index and age. The estimating equation may provide baseline information for the marrow conversion index.

Adolescent↗

Retrospective evaluation of graded stress examination of the ankle.

Stress radiography of the ankle commonly is used to evaluate talar tilt in patients with a history of inversion ankle sprains. Manual and instrumented procedures have been variously described in the literature. No reports have documented normative talar tilt as measured using the Telos ankle stress device in a large clinical population. In addition, little has been done to examine the value of using graded displacement forces compared with a single displacement force. Bilateral Telos examinations from 113 consecutive patients taken during a 4-year period were evaluated for this study. No measurable talar tilt was observed in 65.8% of the ankles in this study. Talar tilt ranged from 1.7 degrees to 24.9 degrees in injured ankles. In patients with quantifiable talar tilt, all had greater talar tilt at the 15 kPa force than at all other forces. Because of the variability in talar tilt in injured and comparison ankles, clinical conclusions regarding injury severity cannot be made on measured talar tilt alone. The analysis suggests that inversion stress examination is helpful in documenting gross talar instability, but the discriminant value of the procedure to determine the anatomy and severity of lateral ligament injury is tenuous.

Adolescent↗

The MR appearance of cruciate ganglion cysts: a report of 16 cases.

Intra-articular ganglion cysts arising from the cruciate ligaments are unusual lesions, there being only nine previously reported cases. We report 16 cases and describe their MR appearance. Nine ganglia originated from the posterior cruciate ligament, most often appearing as well-defined multilocular lesions. The seven ganglia arising from the anterior cruciate ligament most often appeared as fusiform cystic lesions extending along and interspersed within the fibers of the ligament. Although uncommon, intra-articular ganglion cysts arising from the knee appear to have a distinctive MR appearance which should allow their correct diagnosis.

Adult↗

Chest radiographs as a screening test for diffuse idiopathic skeletal hyperostosis.

OBJECTIVE: To evaluate the sensitivity, specificity, predictive value, interrater reliability and intrarater reliability of using chest radiographs as a screening tool for the diagnosis of diffuse idiopathic skeletal hyperostosis (DISH). METHODS: After review of thoracic spine radiographs by 2 "gold standard" physicians, 45 patients with DISH meeting the criteria of Resnick and Niwayama were contrasted with 106 control patients consisting of 45 with thoracic spondylosis, 45 who lacked spondylosis and whose thoracic spine radiographs were otherwise normal for the age of the patient, and 16 with ankylosing spondylitis. The chest radiographs on the 151 subjects were placed in random order and read independently using an ordinal diagnostic certainty scale by 2 "test" radiologists, experienced in reading bone radiographs. Two months later the order of chest radiographs was rerandomized and the films reassessed by the same test radiologists. RESULTS: The averages for the diagnostic and population test characteristics were sensitivity = 77%; specificity = 97%; positive predictive value = 91%; and, negative predictive value = 91%. The area under the receiver operating characteristic curves was 0.975 and 0.976 for the radiologists, and kappa was 0.93, demonstrating that interrater reliability was high. On rereading the chest radiographs, intrarater reliability was exceptional (weighted kappa of 0.90 and 0.96 for the two test radiologists). DISH patients whose chest radiographs were read as not demonstrating DISH had significantly less extensive disease. CONCLUSIONS: We conclude that chest radiographs are a reliable and valid screening tool for the diagnosis of DISH.

Adult↗

Painful shoulder in the hemiplegic and unilateral neglect.

Shoulder pain is a frequent and debilitating problem in hemiplegic patients, and its etiology remains poorly understood. The role played by hemineglect in the appearance of shoulder pain was studied. During two years, 94 hemiplegic subjects were involved in a rehabilitation program after cerebrovascular accidents. Their average age was 68 years; 45 (47.9%) subjects had shoulder pain, and 24 subjects (22.5%) had hemineglect. The subjects with shoulder pain were compared to those without pain (the control group) with respect to gender, age, diabetes, heart failure, cardiac ischemia, scapulohumeral arthritis, and calcified tendinitis of the rotator cuff. We were unable to demonstrate a relationship between hemineglect and shoulder pain in the hemiplegic (X2 (1) = 2.03, p = .15), although pain was significantly more frequent in subjects with right hemispheric cerebrovascular accident (X2 (1) = 5.0, p less than .025). The subjects with shoulder pain had significantly more spasticity of the affected limb (X2 (1) = 26.3, p less than .01), less sensitivity to pinprick of the upper paralyzed extremity (X2 (1) = 10.8, p less than .01), and a more severe subluxation of the affected shoulder (t(51) = 14.0, p less than .01).

Aged↗

[Compulsory internship in diagnostic radiology in the 5th year of medicine at the University of Montreal].

Problems of methodology, organization, and evaluation confronting the radiology departments of the university hospitals affiliated with the University of Montreal, the medical students, and the University itself in connection with an elective internship in radiology offered in the fifth year of medicine, resulted in the formation of a committee to reorganize the course of study. In this concise article the authors describe this and other measures taken by the University to solve these problems. The committees' main purpose was to restructure the internship which was made compulsory so that future physicians would be prepared to draw on the resources of diagnostic radiology and nuclear medicine. To this end, the committee formulated the objectives, content, evaluation system, and pedagogical methods to be used in those courses. The 25 self-teaching modules, together with the observation and practical interpretation of radiology sessions, proved highly useful in solving the initial problems, and were of particular interest to the students.

Curriculum↗

Teleradiology in northern Quebec.

A two-way television network using the Canadian satellite ANIK-B was utilized to transmit radiographic images from Northern Quebec to Montreal. The accuracy of the radiologist's interpretation and his satisfaction with the TV system were studied using a series of 67 preselected cases and 425 current clinical cases. The four participating radiologists gave correct TV interpretations in 81% of the 39 selected cases presented at the beginning of the experiment. This value reached 94% for the other 28 selected cases presented after three months of regular use of the TV system. With current clinical cases, the agreement between TV and direct interpretations was 93%. Although magnification was available, correct identification of very small lesions proved to be the major source of error. On the whole, the radiologists were satisfied with the TV system.

Adult↗

Ewing's sarcoma in adults.

Twenty-two adult patients, aged 18 and over, with Ewing's sarcoma of bone, were evaluated clinically and radiographically. They had clinical findings similar to younger patients with Ewing's sarcoma, except that they presented with fewer systemic symptoms. The radiographic characteristics included a preponderance of flat bone involvement (54%) over long bone involvement (36%). A soft-tissue mass was detected in only 55% of the cases. CT scans, when used, proved to be helpful in delineating a soft-tissue mass associated with the bony lesion, and in follow-up after therapy.

Adolescent↗

The tangential x-ray investigation of the patellofemoral joint: x-ray technique, diagnostic criteria and their interpretation.

The X-ray technique for the tangential visualization of the patellofemoral joint is described; 3 X-ray signs (patellofemoral angle, patellofemoral index and patellofemoral displacement) are proposed as diagnostic aids in cases of subluxation of the patella and chondromalacia patellae. Theoretically, the pathogenesis of chondromalacia patellae and patellofemoral osteoarthritis may be explained as manifestations of cartilage damage secondary to lateral patellofemoral hyperpressure and medial patellofemoral hyperpressure.

Cartilage Diseases↗

The abnormal lateral patellofemoral angle: a diagnostic roentgenographic sign of recurrent patellar subluxation.

On roentgenograms made with the patient supine, the knees flexed 20 to 30 degrees, the x-ray tube between the ankles, and the cassette held proximal to the knees and perpendicular to the x-ray beam, it was found that a line between the femoral condyles and a line between the margins of the lateral facet of the patella formed the lateral patellofemoral angle, an angle that was of diagnostic value in patients with subluxation of the patella. In 100 clinically normal patients, these lines were parallel in three and formed an angle open laterally in ninety-seven. In thirty patients with subluxation of the patella, the lines were parallel in twenty-four and formed an angle open medially in six. In 100 patients with chondromalacia of the patella, however, the roentgenographic study was of no diagnostic value since the lines were parallel in ten and formed an angle open laterally in ninety.

Female↗

MRI of the foot and ankle.

The foot and ankle are among the hardest of all areas to image because of the complex three-dimensional anatomy. Magnetic resonance imaging (MRI), with its multiplanar capabilities, excellent soft-tissue contrast, ability to image bone marrow, noninvasiveness, and lack of ionizing radiation, has become a valuable tool in evaluating patients with foot and ankle problems. MRI is more specific than bone scintigraphy and provides more information than ultrasound and computed tomography. Arthroscopy of the ankle is limited to the articular surface and joint space. MRI allows a global evaluation of the bones, tendons, ligaments, and other structures with a single examination that exceeds the capabilities of all other available techniques. This monograph was written to provide a useful guide to basic technique, indications, positioning, anatomy, and interpretation of foot and ankle MRI. The first part describes the performance of the MRI examination with reference to the positioning of the foot, types of coils, and advantages and disadvantages of the different sequences and imaging planes. The next section was written by an experienced foot and ankle orthopedic surgeon and outlines the indications for MRI for the common foot and ankle symptom complexes and the information that the surgeon hopes to obtain from the study. This is followed by a review of pertinent anatomy, as it applies to imaging, with emphasis on osseous structures, ligaments, tendons, and muscles. The final section is a comprehensive review of the common pathologic conditions encountered in the foot and ankle. We hope that radiologists and radiologists-in-training find this article a useful reference tool and gain a better understanding of this complex area of musculoskeletal imaging.

Animals↗