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Biomedical subjects

L L Seeger

Publications and source records attributed to L L Seeger.

At least 37 records · Page 2Linked to original sources

Saline versus gadolinium-enhanced magnetic resonance arthrography of porcine cartilage.

RATIONALE AND OBJECTIVES: The authors compared saline and dilute gadopentetate dimeglumine as injectants for magnetic resonance (MR) arthrography. METHODS: Sixty-three lesions were created on the joint surfaces of six pig patellas. MR arthrography (1.5 T) was performed with the specimens in saline and then in 2 mmol gadopentetate dimeglumine by using fat-saturated two-dimensional (2D) and three-dimensional (3D) sequences. Two musculoskeletal radiologists independently interpreted the images. RESULTS: At 2D MR arthrography, reader 1 performed equally well with saline and gadolinium solutes, whereas reader 2 had better sensitivity with the saline solute (P < .05); interobserver agreement was equivalent for saline and gadolinium solutes. With 3D MR arthrography, reader 2 performed equally well with saline and gadolinium solutes, whereas reader 1 had better sensitivity (P < .0001) but poorer specificity (P < .001) with the gadolinium solute; interobserver agreement was significantly better for saline than for gadopentetate dimeglumine (P < .05). CONCLUSION: In this initial evaluation, there was no clear advantage to using gadolinium-enhanced MR arthrography over saline MR arthrography for detecting lesions in porcine hyaline cartilage.

Animals↗

CT and MR imaging in the local staging of primary malignant musculoskeletal neoplasms: Report of the Radiology Diagnostic Oncology Group.

PURPOSE: To assess the relative accuracies of computed tomography (CT) and magnetic resonance (MR) imaging in the local staging of primary malignant bone and soft-tissue tumors. MATERIALS AND METHODS: At four institutions, 367 eligible patients (aged 6-89 years) with malignant bone or soft-tissue neoplasms in selected anatomic sites were enrolled. Patients underwent both CT and MR imaging within 4 weeks before surgery. In each patient, CT scans were interpreted independently by two radiologists and MR images by two other radiologists at the enrolling institution. The CT and MR images were then interpreted together by two of those radiologists and subsequently reread at the other institutions. Imaging and histopathologic findings were compared and were supplemented when needed with surgical findings. Receiver operating characteristic curve analysis and descriptive statistical analysis were performed. RESULTS: Cases were analyzable in 316 patients: 183 had primary bone tumors; 133 had primary soft-tissue tumors. There was no statistically significant difference between CT and MR imaging in determining tumor involvement of muscle, bone, joints, or neurovascular structures. The combined interpretation of CT and MR images did not statistically significantly improve accuracy. Interreader variability was similar for both modalities. CONCLUSION: CT and MR imaging are equally accurate in the local staging of malignant bone and soft-tissue neoplasms in the specific anatomic sites studied.

Adolescent↗

A randomized, placebo-controlled trial of calcium supplementation for decreased bone density in corticosteroid-using patients with inflammatory bowel disease: a pilot study.

BACKGROUND: Patients with inflammatory bowel disease (IBD) have a high prevalence of osteoporosis. A number of studies have found that corticosteroid use is associated with the development of osteoporosis in these patients. Calcium supplementation may be of benefit in corticosteroid-induced osteoporosis and calcium may be a nutrient that patients with IBD lack. AIM: To test the benefit of calcium supplementation on bone density in a pilot study over a 1-year period, in a group of corticosteroid-using patients with IBD, in a randomized, double-blind, placebo-controlled treatment study. METHODS: Corticosteroid-using patients with IBD including males over the age of 18 years and premenopausal females, were randomized to receive either calcium carbonate 1000 mg plus vitamin D 250 IU (Oscal) or an identically matched placebo. Dual energy X-ray absorptiometry measurements of bone density were obtained at entry and at 1 year. At entry, and every 3 months thereafter, serum was collected for the measurement of haemoglobin, biochemistry and bone hormones. Simultaneously a 24-h urine collection was analysed for calcium excretion and creatinine clearance, and a 4-day food record was collected to document dietary calcium and vitamin D ingestion. RESULTS: We found a high prevalence of moderately severe decreased bone density in corticosteroid-using patients with IBD. The dose of prednisone in the year prior to study entry was inversely correlated with bone density at the hip (R = -0.67, P = 0.004). At study entry serum osteocalcin was inversely correlated with corticosteroid dose in the year prior to the study (R = -0.64, P = 0.02) and at study end, directly correlated with the percentage change in spine bone density (R = 0.59, P = 0.01). The dietary calcium intake of these patients was close to the current RDA (recommended daily intake) for premenopausal, post-adolescent adults. Calcium supplementation with small extra doses of vitamin D conferred no obvious benefit to bone density at the end of 1 year. There was no correlation between oral calcium ingestion and bone mass measurements. Both the treatment and placebo groups' bone density remained relatively stable at 1 year, suggesting that bone loss in corticosteroid-using patients may peak early into the use of the corticosteroids. CONCLUSIONS: Calcium supplementation (1000 mg/day) conferred no significant benefit to bone density at 1 year in patients with corticosteroid-using IBD patients with osteoporosis. Future investigations should explore other therapeutic avenues that may have greater effects on increasing bone density in patients who already have considerable osteoporosis.

Absorptiometry, Photon↗

Magnetic resonance imaging of plantar plate rupture.

Degenerative plantar plate failure is an under-recognized cause of lesser metatarsalgia. We performed magnetic resonance imaging (MRI) with a small receiver coil in 13 patients in whom plantar plate ruptures of the second or third metatarsophalangeal joint were clinically suspected. In eight patients, MRI showed focal hyperintensity in the plantar plate that was interpreted as a rupture of the plate. Ruptures were confirmed in all five patients who underwent an operative procedure to treat the unstable, painful metatarsophalangeal joint. MRI is a noninvasive technique that can visualize plantar plate abnormalities and aid the clinical evaluation of problematic lesser metatarsalgia.

Aged↗

Pictorial review: foot axes and angles.

Using radiographs and diagrams, this article reviews the most commonly used axes and angles of the foot, including: longitudinal axis of the rearfoot, collum tali axis, talocalcaneal angle, cuboid abduction angle, longitudinal axis of the lesser tarsus, lesser tarsus angle, talonavicular angle, longitudinal axis of the metatarsus, forefoot adductus angle, metatarsus adductus angle, first intermetatarsal angle, hallux valgus angle, proximal and distal articular set angles, and hallux interphalangeal angle, plane of support, collum tali axis, talar declination angle, calcaneal inclination axis, lateral talocalcaneal angle, first metatarsal declination axis and calcaneal inclination angle.

Foot↗

Ribbing disease (multiple diaphyseal sclerosis): imaging and differential diagnosis.

OBJECTIVE: This study describes the clinical presentation and the course of Ribbing disease in six patients and illustrates imaging features on plain radiography, conventional and computed tomography, and 99mTc-methylene diphosphonate bone scans. MATERIALS AND METHODS: Between 1982 and 1990, six female patients presented with painful bony lesions that were believed to be Ribbing disease. Ten bones were affected: both tibiae in three patients, a unilateral tibia in one, both femora in one, and a unilateral femur in one. Plain radiographs and either conventional or computed tomography were available for all patients and 99mTc-methylene diphosphonate bone scans, for five patients. All patients underwent open biopsy and/or surgical decompression. RESULTS: The diagnosis was reached in all patients through a combination of clinical findings (lack of systemic signs of infection or laboratory values suggesting metabolic bone disease), imaging, histologic evaluation, and specimen cultures. Radiographs and tomographic studies showed benign-appearing endosteal and periosteal cortical thickening. Intense uptake of radionuclide tracer was confined to the shaft of all involved bones. All pathologic specimens revealed nonspecific changes that included a slow increase in the mass of cortical and endosteal bone. These specimens also assisted in excluding neoplastic or infectious causes for the new bone formation. CONCLUSION: Ribbing disease is a rare disorder that, on imaging studies, may simulate stress fracture, chronic infection, bone-forming neoplasia, or a systemic metabolic or endocrine disorder. Clinical and imaging features may suggest the correct diagnosis.

Adult↗

Evaluation of rhBMP-2 with an OPLA carrier in a canine posterolateral (transverse process) spinal fusion model.

STUDY DESIGN: Posterolateral L4-L5 transverse process fusions were done on 14 adult beagles. Six were implanted with recombinant human bone morphogenetic protein-2 carried by open-cell polylactic acid polymer delivery vehicle. Six received autogenous iliac bone graft. Two received carrier alone. Eleven were killed 3 months after implantation. One in each group was maintained for 8 months. OBJECTIVES: To compare recombinant human bone morphogenetic protein-2 and open-cell polylactic acid polymer with autogenous iliac bone for inducing transverse process fusion in the canine by 3 months and to determine whether transverse process decortication and implantation of carrier alone causes spontaneous transverse process fusion in the canine. SUMMARY OF BACKGROUND DATA: Recombinant human bone morphogenetic proteins have healed segmental long bone defects in several models. They have induced interlaminar and facet fusions in canines. Interlaminar and facet fusions have occurred after sham decortications in canines. Recombinant human bone morphogenetic protein-2 has not been evaluated for transverse process fusion in canines. Transverse process fusion is a preferred clinical method for achieving posterior lumbar fusion. METHODS: Fusion sites were evaluated by serial computed tomography scans. After the dogs were killed, explanted spines were subjected to manual testing, mechanical testing, high resolution radiography, and histologic analysis. RESULTS: One hundred percent of recombinant human bone morphogenetic protein-2-implanted sites had solid transverse process fusion by 3 months according to all measures. No autografted sites were fused at this interval. Osseous bridging of posterolateral gutters occurred in the recombinant human bone morphogenetic protein-2-implanted sites after 2 months, the earliest radiographic measure. None of the carrier-only sites showed bone formation. CONCLUSIONS: Recombinant bone morphogenetic protein-2 carried by open-cell polyactic acid polymer is superior to autogenous iliac bone for producing radiographically and mechanically solid transverse process fusions in canines by 3 months. Spontaneous transverse process fusion does not occur in canines after decortication and open-cell polylactic acid polymer implantation.

Acetates↗

Decreased bone density in inflammatory bowel disease is related to corticosteroid use and not disease diagnosis.

Although corticosteroid therapy is associated with the development of osteopenia, it is unclear whether the cause of osteopenia in inflammatory bowel disease (Crohn's disease and ulcerative colitis) is related to corticosteroid therapy or other disease-related variables. Patients with Crohn's disease (a diffuse gastrointestinal disease) could have greater osteopenia than patients with ulcerative colitis because of small bowel disease and secondary malabsorption of calcium and vitamin D. A cross-sectional analysis of consecutive patients with Crohn's disease and ulcerative colitis was undertaken. Bone density was determined by measurements of the L2-L4 spine, the total hip, and Ward's triangle using dual energy X-ray absorptiometry (DXA). A number of clinical parameters were recorded prior to bone density evaluation and analyzed by univariate and subsequently multivariate analysis to determine possible predictors of osteopenia. Of the 26 patients with Crohn's disease, diminished bone density (a Z score of at least -1) was found at the hip in 64% and at the spine in 44%; and of the 23 patients with ulcerative colitis diminished bone density was found at the hip in 43% and at the spine in 48%. Among all the variables tested, only corticosteroid use was a statistically significant predictor of diminished bone density (p = 0.025 for the spine and hip and p = 0.005 for Ward's triangle). Disease diagnosis (Crohn's disease compared with ulcerative colitis) did not predict or correlate with diminished bone density. No obvious associations were seen between the measurements of any serum hormones or biochemistries and bone density, although the patients using corticosteroids had lower serum calcium levels than the nonusers.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗

A case of juxta-articular myxoma of the knee.

This 9-year-old girl presented with a painful mass in the posterolateral aspect of her right knee. Excisional biopsy of the mass revealed a juxta-articular myxoma. The differential diagnosis for such an intra- or periarticular mass should include meniscal cyst, parameniscal cyst, ganglion cyst, juxta-articular myxoma, focal nodular PVNS, and desmoid tumor. Current imaging techniques do not allow differentiation between these benign lesions and low grade myxoid-containing sarcoma.

Child↗

Imaging the diabetic foot.

Early and accurate diagnosis of infection or neuropathy of the diabetic foot is the key to successful management. Angiopathy leads to ischemia which, in combination with peripheral neuropathy, predisposes to pedal skin ulceration, the precursor of osteomyelitis. Chronic hyperglycemia promotes production of glycosylated end products which accumulate on endothelial proteins, causing ischemia of the vasa nervorum. When combined with axonal degeneration of the sensory nerves, the result is hypertrophic neuroarthropathy. Should the sympathetic nerve fibers also be damaged, the resultant loss of vasoconstrictive impulses leads to hyperemia and atrophic neuroarthropathy. Plain radiography, although less sensitive than radionuclide, magnetic resonance (MR), and computed tomographic examinations, should be the initial procedure for imaging suspected osteomyelitis in the diabetic patient. If the radiographs are normal but the clinical suspicion of osteomyelitis is strong, a three-phase 99mTc-MDP scan or MR imaging is recommended. An equivocal 99mTc-MDP scan should be followed by MR imaging. To exclude osteomyelitis at a site of neuroarthropathy, a 111In white blood cell scan is preferable. To obtain a specimen of bone for bacteriological studies, percutaneous core biopsy is the procedure of choice, with the entrance of the needle well beyond the edge of the subjacent ulcer.

Biopsy, Needle↗

Uncomplicated cat-scratch disease: findings at CT, MR imaging, and radiography.

PURPOSE: To describe the epidemiologic, clinical, and imaging features of cat-scratch disease (CSD) to facilitate prompt recognition and noninvasive diagnosis of this condition. MATERIALS AND METHODS: Eight otherwise healthy patients with pet cats presented with the subacute onset of epitrochlear, axillary, or groin masses. All underwent cross-sectional imaging with computed tomography (CT) (n = 1) or magnetic resonance (MR) imaging (n = 7). Five patients underwent radiography of the elbow. RESULTS: In all patients, MR imaging and CT showed a poorly defined soft-tissue mass with extensive surrounding edema in an efferent lymphatic distribution. Radiography revealed only soft-tissue edema in two patients and an ill-defined soft-tissue mass with soft-tissue edema in three patients. Six patients underwent biopsy; the findings of all pathologic specimens supported the diagnosis of CSD. No patients underwent serologic evaluation. All patients were asymptomatic within 4 weeks of beginning antibiotic therapy. CONCLUSION: CSD should be considered in all patients with upper extremity or head and neck adenopathy and a history of cat exposure. Although generally not required for diagnosis, cross-sectional imaging will reveal a mass with surrounding edema in an area of lymphatic drainage.

Adolescent↗

The role of plain radiography, computed tomography, and magnetic resonance imaging in sarcoma evaluation.

Imaging plays an important role in the diagnosis, staging, treatment planning, and post-treatment monitoring of bone and soft-tissue sarcomas. Plain radiography should be the initial imaging undertaken for patients who present with pain or a mass that may represent a musculoskeletal tumor. This is especially true of bony lesions, in which plain radiography remains the most specific noninvasive means of determining the aggressiveness of a lesion and establishing a working differential diagnosis.

Bone Neoplasms↗

Multicentric giant cell tumor: report of five new cases.

The typical giant cell tumor (GCT) is a solitary neoplams that occurs in the epiphysis or epimetaphysis of long bones. GCT is seen with a slightly increased frequency in females, and 70% of patients are between 20 and 40 years of age at the time of presentation. Multicentric giant cell tumor (MGCT; two or more centers) is an unusual variant of GCT. Patients with MGCT are likely to be younger than those with a solitary lesion. The multicentric variety is often of a higher stage at diagnosis and is more often associated with a pathological fracture than the unifocal tumor. We are reporting five new cases of MGCT, with a total of 21 tumors seen over a period of 25 years from 1967 to 1992.

Adolescent↗

MR imaging of tibial collateral ligament injury: comparison with clinical examination.

We sought to clarify the capability of routine magnetic resonance (MR) imaging of the knee to detect and grade tibial collateral ligament (TCL) injury. We also wanted to define the exact MR findings that were the most important for diagnosis. Sixty-three patients were clinically evaluated for TCL injury prior to MR imaging of the knee on a 1.5-tesla system. MR studies were scored with respect to multiple direct and indirect findings. By discriminant analysis, the overall accuracy of classification (into clinical grades 1, 2, 3 and normal) on the basis of MR was 65%. Accuracy for detection of abnormal TCLs was 87%. The most useful MR findings for detection and grading of TCL injury were direct signs: subcutaneous edema over the TCL, focal disruption of the TCL, increased signal in the TCL on T2-weighted images, and longitudinal striations within the TCL. Indirect signs such as trabecular trauma were less useful for TCL evaluation. The presence of a tear of the anterior cruciate ligament, however, correlated with TCL injury of a higher grade. T2-weighted coronal images, by better depicting intraligamentous edema and fiber disruption, improved the MR assessment of the TCL.

Humans↗