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R D Boutin

Publications and source records attributed to R D Boutin.

At least 19 recordsLinked to original sources
PubMed2001

Protocol issues for delayed Gd(DTPA)(2-)-enhanced MRI (dGEMRIC) for clinical evaluation of articular cartilage.

Biochemical and histologic data have validated the technique of delayed gadolinium-enhanced MRI, in which the T(1) values of cartilage after penetration of Gd(DTPA)2-allow assessment of the glycosaminoglycan (GAG) component of articular cartilage. This work describes the factors that have been found to be important for the practical implementation of the technique: 1) Exercise immediately after intravenous contrast administration was necessary for effective penetration of the contrast into the articular cartilage; 2) double-dose contrast was better than single-dose; 3) after contrast administration, a time window of 30-90 min for the hip, and 2-3 hr for all compartments of the knee proved to be appropriate for assessing articular cartilage; and 4) in some cases of hypointensities in the subchondral patellar bone, decreased penetration of the contrast agent into cartilage from bone was found. With the protocol described, ROIs on T(1) images were reproducible within 15% on two separate imaging sessions, and initial clinical studies demonstrated the possible applications of the technique. Magn Reson Med 45:36-41, 2001.

Cartilage, Articular↗
PubMed2001

Postoperative magnetic resonance imaging of articular cartilage repair.

The treatment of articular cartilage injuries remains a challenge because cartilage has a limited capacity for spontaneous repair. Over the past decade, a number of surgical interventions have been developed to produce a durable repair. This article reviews the available treatment options, including their indications, technique, and clinical results, and illustrates the MR imaging appearance of normal repair sites and postoperative complications.

Bone Nails↗
PubMed2001

Shell osteochondral allografts of the knee: comparison of mr imaging findings and immunologic responses.

PURPOSE: To define the magnetic resonance (MR) imaging appearance of shell osteochondral allografts of the knee and compare the MR findings with antibody responses. MATERIALS AND METHODS: Thirty-six grafts were evaluated with a 1.5-T unit with T1-, intermediate-, and T2-weighted, and three-dimensional spoiled gradient-recalled MR imaging at 3, 6, 12, 24, and/or 36 months after surgery. Nineteen patients underwent imaging serially. Two osteoradiologists scored by consensus host marrow edema, thickness of graft-host interface, signal intensity of graft marrow, cyst formation, joint effusion, articular cartilage defects, and surface collapse. Patients were divided into antibody-positive (AP) (n = 11) and antibody-negative (AN) (n = 25) groups evenly distributed across the different time points on the basis of results of anti-human leukocyte antigen antibody screening. MR findings for the two groups were compared. RESULTS: AP patients demonstrated greater mean edema (P<.002), thicker interface (P<.03), and more abnormal graft marrow (P<.04) than AN patients, and they had a higher proportion of surface collapse (P<.03). CONCLUSION: Humoral immune responses were associated with more inflammation and less complete incorporation after allograft placement. MR imaging shows promise as a surrogate biomarker for success of shell osteochondral allograft implantation.

Adolescent↗
PubMed2001

Polydioxanone biodegradable pins in the knee: MR imaging.

OBJECTIVE: Biodegradable solid implants have been developed as an alternative to metallic orthopedic fixation. In animal models, implants degrade within and are replaced by bone. This study documents the resorption of these devices in human patients with MR imaging. SUBJECTS AND METHODS: One hundred seventy-five 1.3-mm biodegradable pins made of polydioxanone were used to secure a total of 59 osteochondral allografts of the knee. Patients with the pins underwent scanning on a 1.5-T unit with 3.3- to 4-mm contiguous T1-weighted spin-echo (TR/TE, 600/15), fat-saturated proton density-weighted (3000/40), T2-weighted fast spin-echo (3000/63), and three-dimensional spoiled gradient-recalled (47/7; flip angle, 60 degrees ) sequences at 3, 6, 12, 24, or 36 months after surgery. Eighty-nine pins were imaged on multiple occasions. Two osteoradiologists interpreted the MR examinations. RESULTS: More than 80% of the pin channels were visible at 3 and at 6 months after surgery. By 24 months, only 20% of the pin channels were visible, with the remainder having been replaced by bone. At 3 months, nearly 40% of the pins were associated with adjacent marrow edema. Edema generally diminished, involving less than 20% of pins at later time points. Focal cartilage defects were evident at 32% of the pin insertion sites during the first 6 months, but these defects were present in only 4% of the insertion sites thereafter. CONCLUSION: Biodegradable polydioxanone pins usually resorb completely by 24 months. Marrow edema, presumably representing inflammation related to pin resorption, is infrequent and tends to resolve. Cartilage defects related to pin placement heal spontaneously.

Absorbable Implants↗
PubMed2001

Magnetic resonance imaging of the peripheral nervous system.

An accurate diagnosis is the essential first step toward a successful treatment plan in patients who present with pain and suspected nerve entrapment. Pain and dysfunction are often related to an acute traumatic event or a classic presentation that leads to a straightforward clinical diagnosis. The diagnostic approach to abnormalities of the peripheral nervous system always begins with a thorough history and physical examination. Imaging may play an important role in confirming the initial clinical [figure: see text] diagnosis so that a rational plan of treatment may be selected. Diagnostic imaging is especially important when there is significant uncertainty regarding the cause of pain and the outcome may be improved by timely implementation of various treatment options. Diagnostic accuracy is important when various conditions in the differential diagnosis would be treated differently from the beginning. Indeed, certain conditions that result in pain and dysfunction related to peripheral nerve entrapment are best treated with initial rest, protection, and rehabilitation whereas other conditions are best treated with prompt surgery. Promptly arriving at an accurate diagnosis is an essential step in designing a rational course of therapy, in achieving a good outcome, and in treating medical conditions in a timely fashion. Indeed, because pain is mediated through peripheral nerves, establishing an accurate diagnosis is especially important in disorders of the peripheral nervous system in which there may be considerable pain and suffering with an incorrect or delayed diagnosis. Moreover, an early diagnosis is desirable [figure: see text] to preserve motor power and sensory function in cases of clinically occult nerve entrapment. Although entrapment syndromes are well described and widely documented in the literature, they may be easily missed in clinical practice in certain instances. Although MR imaging is useful to confirm and characterize a known or suspected case of peripheral nerve entrapment, there may be evidence of peripheral nerve pathology that is first detected with MR imaging. Clinically unsuspected nerve entrapment may occur in patients with occult dorsal ganglion cysts in the wrist that may entrap the posterior interosseous nerve and produce pain without other symptoms. In addition, the authors routinely see patients with paralabral cysts secondary to tears of the superior labrum in the shoulder resulting in entrapment of the suprascapular nerve. This diagnosis is usually not suspected clinically until there is relatively advanced weakness and muscular atrophy in addition to shoulder pain. MR imaging remains an evolving technique with ongoing improvements in technology and developing clinical experience, resulting in greater diagnostic capacity. In this article current technique and strategies for image analysis and the authors' specific clinical experience with MR imaging of peripheral nerve disorders are reviewed. The exact role of MR imaging in the evaluation of these disorders will be further defined with additional experimental work and published clinical experience.

Humans↗
PubMed2000

Calcium pyrophosphate dihydrate crystal deposition in and around the atlantoaxial joint: association with type 2 odontoid fractures in nine patients.

PURPOSE: To investigate the histopathologic anatomy of calcium pyrophosphate dihydrate (CPPD) crystal deposition in and around the atlantoaxial joint and the association between CPPD crystal deposition and subchondral cysts, erosions, and fracture involving the odontoid process of the axis. MATERIALS AND METHODS: One adult cadaver demonstrating calcification in the retro-odontoid area at computed tomography (CT) was selected for further radiography, CT, and magnetic resonance (MR) imaging at the C1-2 level. Anatomic sectioning and histologic evaluations were performed in the specimen. For clinical study, radiographs (n = 5), CT scans (n = 8), and MR images (n = 6) in nine patients (mean age, 74.4 years) with odontoid process fractures and CPPD crystal deposits in and around the atlantoaxial joint were reviewed. RESULTS: In the cadaveric specimen, radiography and CT demonstrated calcifications in the transverse ligament; histologic evaluation confirmed that these calcifications were CPPD crystal deposits. In all nine patients, radiography (n = 5) and CT (n = 8) also showed calcification in areas adjacent to the odontoid process, which included the transverse ligament. T1- and T2-weighted MR imaging showed a retro-odontoid mass of low signal intensity that compressed the cervical cord in six patients. CT, MR imaging, or both demonstrated subchondral cysts, osseous erosions, or a type 2 odontoid fracture in all patients. CONCLUSION: CPPD crystal deposition disease involving the C1-C2 articulation can be a clinically important entity that may place affected patients at increased risk of pathologic fracture of the odontoid process.

Aged↗
PubMed2000

Pulley system in the fingers: normal anatomy and simulated lesions in cadavers at MR imaging, CT, and US with and without contrast material distention of the tendon sheath.

PURPOSE: To describe the normal anatomy of the finger flexor tendon pulley system, with anatomic correlation, and to define criteria to diagnose pulley abnormalities with different imaging modalities. MATERIALS AND METHODS: Three groups of cadaveric fingers underwent computed tomography (CT), magnetic resonance (MR) imaging, and ultrasonography (US). The normal anatomy of the pulley system was studied at extension and flexion without and with MR tenography. Pulley lengths were measured, and anatomic correlation was performed. Pulley lesions were created and studied at flexion, extension, and forced flexion. Two radiologists reviewed the studies in blinded fashion. RESULTS: MR imaging demonstrated A2 (proximal phalanx) and A4 (middle phalanx) pulleys in 12 (100%) of 12 cases, without and with tenography. MR tenography showed the A3 (proximal interphalangeal) and A5 (distal interphalangeal) pulleys in 10 (83%) and nine (75%) cases, respectively. US showed the A2 pulley in all cases and the A4 pulley in eight (67%). CT did not allow direct pulley visualization. No significant differences in pulley lengths were measured at MR, US, or pathologic examination (P: =.512). Direct lesion diagnosis was possible with MR imaging and US in 79%-100% of cases, depending on lesion type. Indirect diagnosis was successful with all methods with forced flexion. CONCLUSION: MR imaging and US provide means of direct finger pulley system evaluation.

Aged↗
PubMed2000

Characterization of the "red zone" of knee meniscus: MR imaging and histologic correlation.

PURPOSE: To determine the extent and vascularity of knee menisci with conventional and gadolinium-enhanced magnetic resonance (MR) imaging in cadaveric specimens, with histologic findings as the reference standard, and to investigate signal intensity changes in menisci and perimeniscal soft tissues in symptomatic patients. MATERIALS AND METHODS: Radial dimensions and enhancement patterns of menisci were recorded and compared in (a) 12 cadaveric menisci examined with conventional and gadolinium-enhanced intermediate-weighted and fat-suppressed T1-weighted spin-echo MR imaging, high-spatial-resolution T1-weighted and fast low-angle shot MR imaging, and gross anatomic and histologic specimens and (b) 18 patients examined with conventional and gadolinium-enhanced fat-suppressed T1-weighted spin-echo MR imaging. RESULTS: No differences in radial measurements of the meniscus were found for different MR techniques (P =.551). Despite the presence of vessels in the peripheral 10%-15% of the menisci, no enhancement of menisci was detected in specimens or patients. Perimeniscal soft-tissue enhancement adjacent to the posterior horn was greater than that adjacent to the anterior horn (P <.05), and enhancement of the lateral meniscal body was greater than that of the medial meniscal body (P <.05). CONCLUSION: The wedge-shaped low-signal-intensity structure seen on MR images represents the entire meniscus. Intravenous injection of contrast material does not appear to be useful for differentiation of the vascularized from the nonvascularized zone of the meniscus.

Aged↗
PubMed2000

MR imaging of degenerative diseases in the cervical spine.

This article reviews three topics of fundamental importance in MR imaging of degenerative diseases in the cervical spine: (1) common clinical presentations that determine whether an MR examination is ordered and the ultimate significance ascribed to MR imaging results; (2) imaging techniques; and (3) MR imaging of the major types of cervical spine degeneration.

Cervical Vertebrae↗
PubMed1999

Post-traumatic and stress-induced osteolysis of the distal clavicle: MR imaging findings in 17 patients.

OBJECTIVE: To describe the MR imaging findings in patients with osteolysis of the distal clavicle and to compare the MR imaging appearance of clavicular osteolysis following acute injury with that related to chronic stress. DESIGN AND PATIENTS: MR imaging examinations were reviewed in 17 patients (14 men, 3 women; ages 16-55 years) with the diagnosis of post-traumatic or stress-induced osteolysis of the clavicle. A history of a single direct injury was present in seven patients and a history of weight-lifting, participation in sports, or repetitive microtrauma was present in 10 patients. RESULTS: MR imaging showed edema in the distal clavicle in 17 patients and, of these, eight also had edema in the acromion. The edema was most evident in STIR and fat-suppressed T2-weighted pulse sequences. Other findings about the acromioclavicular (AC) joint were prominence of the joint capsule in 14, joint fluid in eight, cortical irregularity in 12, and bone fragmentation in six patients. No differences in the MR imaging features of post-traumatic and stress-induced osteolysis of the distal clavicle were observed. CONCLUSION: Post-traumatic and stress-induced osteolysis of the distal clavicle have similar appearances on MR imaging, the most common and conspicuous MR imaging feature being increased T2 signal intensity in the distal clavicle.

Acromioclavicular Joint↗
PubMed1999

Evaluation of the postoperative meniscus of the knee: a study comparing conventional arthrography, conventional MR imaging, MR arthrography with iodinated contrast material, and MR arthrography with gadolinium-based contrast material.

OBJECTIVE: To compare four imaging methods in the evaluation of the postoperative meniscus: conventional arthrography, conventional MR imaging, MR arthrography with iodinated contrast material, and MR arthrography with gadolinium-based contrast material. DESIGN AND PATIENTS: Thirty-three patients referred for knee MR examinations with a history of meniscal surgery were studied prospectively. At the first patient visit, conventional MR examination was followed by an MR arthrogram with gadolinium-based contrast material. At the second visit, a conventional arthrogram with iodinated contrast material was followed immediately by an MR examination. Imaging examinations were interpreted by a masked reader, and then compared with the results of repeat arthroscopic surgery in 12 patients. RESULTS: The correct evaluation of the status of postoperative menisci was allowed in 12 of 13 patients (92%) by MR arthrography using gadolinium-based contrast agent, 10 of 13 patients (77%) by conventional MR examination, 9 of 12 patients (75%) by MR arthrography, and 7 of 12 patients (58%) by conventional arthrography. CONCLUSION: Intra-articular fluid is advantageous in the evaluation of patients with a suspected meniscal retear. MR arthrography with gadolinium-based contrast material is the most accurate imaging method for the diagnosis of meniscal retears.

Adult↗
PubMed1999

Stress fractures of the lateral metatarsal bones in metatarsus adductus foot deformity: a previously unrecognized association.

OBJECTIVE: To document a distinctive pattern of stress fractures in the lateral metatarsal bones of patients with metatarsus adductus foot deformity. DESIGN AND PATIENTS: Conventional radiographs and available medical records were reviewed in 11 patients (6 women, 5 men; ages 25-61 years) with stress fractures of the lateral (fourth or fifth) metatarsal bones and metatarsus adductus. Evaluation included the number and location of fracture(s), forefoot adduction angle, and qualitative assessment of bone mineral density. Conditions that might predispose patients to metatarsal fractures, including direct trauma, osteoporosis, and neuropathic osteoarthropathy were also recorded. RESULTS: A total of 22 stress fractures were demonstrated, 17 of which involved the lateral metatarsals. A solitary fracture was present in six patients, while multiple fractures were evident in five patients. The sites of involvement were the fifth metatarsal (n=10), fourth metatarsal (n=7), third metatarsal (n=3), second metatarsal (n=1), and first metatarsal (n=1) bones. The locations of the stress fractures were in the proximal one-third of the metatarsal bones in 19 instances (86%) and in the middle one-third in three instances (14%). Forefoot adduction angle measured between 21 degrees and 37 degrees (normal range 8 degrees -14 degrees). CONCLUSION: Patients with metatarsus adductus may be at increased risk for stress fractures involving the lateral metatarsal bones, likely owing to the presence of altered biomechanics that place greater loads across the lateral aspect of the foot.

Adult↗
PubMed1999

Iliotibial band friction syndrome: MR imaging findings in 16 patients and MR arthrographic study of six cadaveric knees.

PURPOSE: To define magnetic resonance (MR) imaging findings in patients with the iliotibial band friction syndrome (ITBFS) and to correlate these findings with anatomic features defined at magnetic resonance (MR) arthrography in cadavers. MATERIALS AND METHODS: The anatomic relationship of the iliotibial tract (ITT) to the lateral recesses of the knee joint and the lateral femoral epicondyle was investigated with MR arthrography at full extension and at 30 degrees and 60 degrees of knee flexion in six cadaveric knees. Seventeen MR imaging studies in 16 patients with ITBFS were evaluated. RESULTS: In the cadaveric study, no interference of the lateral synovial recess with the lateral femoral epicondyle at full extension and at 30 degrees and 60 degrees of knee flexion was observed. In all specimens, correlation of MR images with macroscopic and microscopic sections revealed no primary bursa between the lateral femoral epicondyle and the ITT. In clinical studies, MR imaging findings of poorly defined signal intensity abnormalities or circumscribed fluid collections were located in a compartmentlike space confined laterally by the ITT and medially by the meniscocapsular junction, the lateral collateral ligament, and the lateral femoral epicondyle. CONCLUSION: MR imaging accurately depicts the compartmentlike distribution of signal intensity abnormalities in patients with ITBFS.

Adolescent↗
PubMed1999

Bicipitoradial bursitis: MR imaging findings in eight patients and anatomic data from contrast material opacification of bursae followed by routine radiography and MR imaging in cadavers.

PURPOSE: To use radiography and magnetic resonance (MR) imaging after contrast material opacification of the bursae in cadaveric specimens to demonstrate the anatomy of the bicipitoradial bursa and to report MR imaging findings in patients with bicipitoradial bursitis. MATERIALS AND METHODS: Bicipitoradial bursa in eight cadaveric elbows were injected with a solution containing gadodiamide, iodinated contrast agent, and gelatin. Radiographs and MR images were obtained in each specimen, with both supination and pronation of the forearm. The morphology and relationships of the bursa were studied. Anatomic sections subsequently were obtained. MR imaging studies in eight patients with bicipitoradial bursitis were also evaluated. RESULTS: The bicipitoradial bursa revealed a smooth outline and a wide base along the superficial aspect of the radius. The mean volume of contrast material that could be injected before extravasation was 4 mL. The mean size of the bursa was 1.8 x 2.5 cm. The bicipitoradial bursa enveloped the biceps tendon, with internal septation seen in two cases. Displacement of the superficial branch of the radial nerve by the bursa was found in two specimens. Communication between the bicipitoradial bursa and elbow joint was not observed. In patients, MR imaging demonstrated fluid collections in the bicipitoradial bursa in all cases, with compression of branches of the radial nerve in two cases. CONCLUSION: The anatomy of the bicipitoradial bursa is demonstrated with radiography and MR imaging of bursae. MR imaging allows accurate diagnosis of bicipitoradial bursitis and its effects on adjacent structures.

Adult↗
PubMed1998

Update on imaging of orthopedic infections.

Although the diagnosis of infection is only a small part of the orthopedist's job description, it is a important part. This article discusses the fundamentals of orthopedic infections and highlights the refinements on this topic from a radiologic perspective. In addition to reviewing the imaging appearance of musculoskeletal infections in bone and the surrounding soft tissues, we focus on the advantages and disadvantages of five imaging methods: radiography, sonography, CT, scintigraphy, and MR imaging. Finally, we review three specific situations that have garnered substantial attention in recent medical literature: chronic recurrent multifocal osteomyelitis, musculoskeletal infections in AIDS patients, and pedal infections in diabetic patients.

Diabetic Foot↗
PubMed1998

Complications in Paget disease at MR imaging.

PURPOSE: To determine the MR imaging findings in patients with complications of Paget disease of bone. MATERIALS AND METHODS: Of 45 patients with Paget disease who underwent MR imaging, 33 (26 men, seven women; age range, 64-91 years) with known complications of the disease were examined. Imaging in this subgroup included radiography (n = 26), computed tomography (n = 12), bone scintigraphy (n = 15), and magnetic resonance (MR) imaging (n = 33). Patients were examined specifically for musculoskeletal and neurologic complications of Paget disease, including fracture, basilar impression, spinal stenosis, bone tumor, and osteoarthrosis. RESULTS: The 56 complications documented in the 33 patients were fracture (n = 17), neurologic entrapment (n = 19), neoplasm (n = 9), and arthropathy (n = 11). MR imaging was beneficial in the diagnostic evaluation of basilar impression (n = 7), spinal stenosis (n = 12), and the tumor stage (n = 9). It also helped to successfully evaluate pagetic bone narrowing of the coracoacromial arch, which was associated with impingement syndrome and rotator cuff rupture (n = 2). The signal intensities in pagetic bone were most commonly similar to those in fat; this finding had a 100% negative predictive value in excluding neoplasm. CONCLUSION: Although Paget disease is diagnosed economically with conventional radiography, MR imaging is well suited for demonstrating the presence and extent of several characteristic disease complications, including basilar impression, spinal stenosis, and secondary neoplasm.

Aged↗