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W W Scott

Publications and source records attributed to W W Scott.

At least 55 records · Page 3Linked to original sources
PubMed1993

Reliability of grading scales for individual radiographic features of osteoarthritis of the knee. The Baltimore longitudinal study of aging atlas of knee osteoarthritis.

RATIONALE AND OBJECTIVES: The authors present an atlas of individual radiographic features of osteoarthritis of the knee and evaluate the inter- and intra-reader reliability of trained readers using this atlas. METHODS: Four trained readers graded 30 standing anterior-posterior knee radiographs for eight selected features of osteoarthritis (medial and lateral osteophytes, joint space narrowing, and sclerosis; osteophytes of the tibial spines and chondrocalcinosis) as well as the Kellgren-Lawrence global scale. Inter- and intra-reader reliability were calculated using intraclass correlation coefficients. RESULTS: For all features except sclerosis and osteophytes of the tibial spines, inter-reader reliability ranged from 0.63 to 0.83, whereas intra-reader reliability ranged from 0.82 to 0.95. CONCLUSION: Using this atlas, trained readers are reliable in measuring the presence and severity of individual radiographic features of osteoarthritis of the knee. This atlas should be useful in clinical and epidemiologic studies of osteoarthritis of the knee.

Adult↗
PubMed1992

Computed tomography appearance of bone metastases of leiomyosarcoma.

Bone lesions in leiomyosarcoma are uncommon. When encountered, they are usually a late manifestation of disease seen in the setting of widespread systemic metastases. We present five cases of metastatic leiomyosarcoma, including one in which a bone lesion predated detection of a primary gastric leiomyosarcoma and one in which bone metastases signaled disease recurrence. Computed tomography in 14 of 16 osseous leiomyosarcomas demonstrated a lytic, non-expansile pattern.

Adult↗
PubMed1992

Sex differences in geometry of the femoral neck with aging: a structural analysis of bone mineral data.

The greater hip fracture rate among elderly women is generally ascribed to differences in femoral neck strength between the sexes. Strength of a given bone is a function of both its material properties and the magnitudes of mechanical stresses within it. This study examined the hypothesis that these apparent strength differences between the sexes are due to dissimilarities in the restructuring of the femoral neck with age, which result in higher stresses in elderly women. Using Hip Strength Analysis, a computer program developed by the authors, femoral neck cross-sectional geometric properties for stress analyses were derived from bone mineral image data of 409 community living, white subjects ranging from 19 to 93 years of age. Though both sexes show declines in femoral neck bone mineral density (BMD) and cross-sectional area with age, only females show a decline in the cross-sectional moment of inertia (CSMI, a geometric index of bone rigidity). The lack of decline in male CSMI appears to be a result of a small but significant increase in femoral neck girth. Similar age-related changes have been observed in the femoral shaft by others. The net effect of these observed changes is that mechanical stresses in the femoral neck of females appear to increase at three times the rate per decade of those of males. These results lend support to the hypothesis that the higher fracture rate in elderly women is due, at least in part, to elevated levels of mechanical stress, resulting from a combination of greater bone loss and less compensatory geometric restructuring with age.

Adult↗
PubMed1992

Phantom for use in lung biopsy training.

A phantom to assist in the teaching of fluoroscopically guided transthoracic needle biopsy of pulmonary lesions was designed. The phantom was constructed of an aluminum and rubber skeleton, wood hemidiaphragms and heart, and foam rubber lungs and was covered with foam rubber. Modeling clay was used to simulate lesions. The authors believe the phantom is of value in helping increase the confidence and proficiency of the radiologist during the first few biopsy procedures with an actual patient.

Biopsy, Needle↗
PubMed1992

Comparison of helical and serial CT with regard to three-dimensional imaging of musculoskeletal anatomy.

To test the hypothesis that helical computed tomographic (CT) scans provide three-dimensional images as good as or better than those provided by serial CT, two objects were used to study the effects of helical CT: an angled cylindrical bone phantom and a human cadaveric femur specimen with a simulated fracture 1 mm wide. Both objects were immersed in a water bath, and a series of helical and serial CT scans were obtained with various parameters. Volumetric rendering was applied to the resultant data sets to create three-dimensional images, which three radiologists reviewed in a blinded manner to rate their fidelity, accuracy, and diagnostic usefulness. As expected, the images obtained with thin collimation and small intersection spacing or slow table movement were considered superior. Helical and serial CT data acquired with similar parameters were similar in quality, but helical CT is approximately five times faster than serial CT; hence, it is possible to use thinner collimation and obtain more sectional data with helical CT.

Femur↗
PubMed1992

Growth potential of porcine reduced-size mature pulmonary lobar transplants.

The use of mature pulmonary lobes for pediatric lung transplantation has recently been described. Successful application of this technique could help alleviate the pediatric donor lung shortage. Whether an already mature lobe can grow by forming new alveolar units after transplantation into a developing recipient is not known. We therefore measured functional residual capacity, fixed lung volume and weight, alveolar size and air space volume percent, and total number of alveoli in mature left lower lobe porcine lung transplants 12 weeks after transplantation into growing piglets. Comparisons were made with nontransplanted mature left lower lobes to determine if functional or morphologic growth had occurred after transplantation. The transplanted and control lobes were all taken from 6-month-old animals (mean body weight 105 +/- 4 kg). Recipients of the transplanted lobes were 9 weeks old and weighed 22 +/- 2 kg. By the end of the 12-week holding period, the recipient animals increased their body weight approximately fourfold (85 +/- 4 kg). No significant differences were seen in functional residual capacity or morphologic analysis of total alveolar number and alveolar size between the transplanted and nontransplanted lobes (p = not significant). Although the reduced-size mature porcine lobar transplants did not display a significant increase in either functional residual capacity or total alveolar number, there was significant growth of the transplanted mature lobes as determined by fixed volume and total lobar weight (p < or = 0.05 versus control animals).

Animals↗
PubMed1991

Articular and diaphyseal remodeling of the proximal femur with changes in body mass in adults.

Proximal femoral dimensions were measured from radiographs of 80 living subjects whose current body weight and body weight at initial skeletal maturity (18 years) could be ascertained. Results generally support the hypothesis that articular size does not change in response to changes in mechanical loading (body weight) in adults, while diaphyseal cross-sectional size does. This can be explained by considering the different bone remodeling constraints characteristic of largely trabecular bone regions (articulations) and largely compact cortical bone regions (diaphyses). The femoral neck shows a pattern apparently intermediate between the two, consistent with its structure. When the additional statistical "noise" created by an essentially static femoral head size is accounted for, the present study supports other studies that have demonstrated rather marked positive allometry in femoral articular and shaft cross-sectional dimensions to body mass among adult humans. Body weight prediction equations developed from these data give reasonable results for modern U.S. samples, with average percent prediction errors of about 10%-16% for individual weights and about 2% for sample mean weights using the shaft dimension equations. When predicting body weight from femoral head size in earlier human samples, a downward correction factor of about 10% is suggested to account for the increased adiposity of very recent U.S. adults.

Adult↗
PubMed1991

Case report 698: Osteoma of the clavicle.

We have presented a case of an osteoma of the clavicle in a 41-year-old man. The possibility of alternate diagnoses--in particular, ancient osteochondroma, posttraumatic hyperostosis, and parosteal osteosarcoma--was addressed. However, the pathological examination was most consistent with the diagnosis of osteoma. This benign bone lesion is most often found in the calvarium, jaw, and face. Osteomas of long bones remain extremely rare, except in the setting of Gardner's syndrome.

Adult↗
PubMed1991

Bone marrow perfusion evaluated with gadolinium-enhanced dynamic fast MR imaging in a dog model.

The authors studied, in a dog model, the feasibility of using gadolinium-enhanced dynamic magnetic resonance (MR) imaging to noninvasively monitor bone marrow perfusion of the proximal femur. With a gradient-recalled acquisition, sequential images of 10 hips in five healthy dogs were obtained for 14 minutes after an intravenous bolus injection of 0.2 mmol of gadopentetate dimeglumine per kilogram. The study was repeated after unilateral arterial embolization of major femoral vessels. Radiolabeled microspheres were injected before and after vessel occlusion. After unilateral embolization, statistically significant differences in enhancement were observed between embolized and control sides (eg, 31% vs 83% average peak enhancement in the femoral neck). There was a high correlation (r = .81 [average]) between the MR data and the microsphere blood flow measurements. The postembolization data indicate that contrast-enhanced fast MR imaging may allow early detection of abnormal bone marrow flow. This technique may be valuable in evaluating patients at risk for avascular necrosis of the femoral head, especially in posttraumatic cases.

Animals↗
PubMed1991

Focal pulmonary lesions in patients with AIDS: percutaneous transthoracic needle biopsy.

The authors performed percutaneous transthoracic needle biopsy (PTNB) in 13 patients with acquired immunodeficiency syndrome (AIDS) and previously undiagnosed focal pulmonary lesions. Findings with PTNB were diagnostic in 11 of 13 cases. Complications included minimal hemoptysis in one case and small pneumothoraxes in two cases, one of which required chest tube drainage. The authors did not experience the high complication rate reported previously by some authors who used this diagnostic procedure in AIDS patients. In cases in which findings at fiberoptic bronchoscopy with transbronchial biopsy and lavage failed to provide a diagnosis, PTNB provided a reliable, relatively safe diagnostic tool to establish the cause of pulmonary masses or focal infiltrates in AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1990

The longitudinal course of hand osteoarthritis in a male population.

In this prospective analysis of the natural history of osteoarthritis (OA) of the hand, the incidence and progression of various radiographic features of OA were examined in 177 men who participated in the Baltimore Longitudinal Study of Aging. Subjects who were less than 60 years old were selected based on the availability of at least 4 hand radiographs taken during at least 20 years of followup, while subjects who were age 60 or older were required to have had at least 4 hand radiographs taken during only 14 years of followup. Individual joints of the hands were graded for the presence and severity of 5 features of OA: osteophytes, joint space narrowing, subchondral sclerosis, lateral deformity, and cortical collapse. They were also graded according to the global Kellgren/Lawrence scale. The incidence and rate of progression of OA, as measured by all scales, increased in progressively older age groups. Cox's proportional hazards models showed that isolated doubtful osteophytes (Kellgren/Lawrence grade 1) and isolated joint space narrowing predicted the development of the radiographic features of OA. The rate of OA progression slowed as the severity increased. We conclude that, in men, the incidence of radiographic features of hand OA increases with age. Regardless of age, the earliest radiographic signs of OA are joint space narrowing and doubtful osteophytes.

Aging↗
PubMed1990

Computed tomography evaluation of the sacroiliac joints in Crohn disease. Radiologic/clinical correlation.

Computed tomography (CT) was used in a prospective study of the sacroiliac joints in 86 patients with Crohn disease to determine the type and frequency of sacroiliac joint abnormalities present in this population. The CT findings were correlated with review of the clinical history in 64 patients. Computed tomography demonstrated changes of sacroiliitis in 29% of the study group. This high prevalence of sacroiliac joint abnormality was found even in those under 30 years of age. It exceeds the 11-19% previously reported from plain film examination, reflecting the greater sensitivity of CT. In the subgroup of 64 patients studied clinically, 19 (30%) had abnormal sacroiliac joints on CT, but only 2 (3%) reported symptoms related to the sacroiliac joints.

Adult↗
PubMed1990

Predicting femoral neck strength from bone mineral data. A structural approach.

An interactive computer program was developed to derive femoral neck geometry from raw bone mineral image data for an estimate of hip strength using single plane engineering stress analysis. The program, which we call Hip Strength Analysis (HSA), was developed as an attempt to improve the predictive value of hip bone mineral data for osteoporosis fracture risk assessment. We report a series of experiments with an aluminum phantom and with cadaver femora, designed to test the accuracy of derived geometric measurements and strength estimates. Using data acquired with both Lunar DP3 (DPA) and Hologic QDR-1000 (x-ray) scanners, HSA computed femoral neck cross-sectional areas (CSA) and cross-sectional moments of inertia (CSMI) on an aluminum phantom were in excellent agreement with actual values (r greater than .99). Using Lunar DP3 data, CSA and CSMI measurements at mid-femoral necks of 22 cadaver specimens were in good general agreement with literature values. HSA computed cross-sectional properties of three of these specimens were compared with measurements derived from sequential CT cross-sectional images. Discrepancy between the two methods averaged less than 10% along the length of the femoral neck. Finally, breaking strengths of 20 of the femora were measured with a materials testing system, showing better agreement with HSA predicted strength (r = .89, percent standard of the estimate (%SEE) = 21%) than femoral neck bone mineral density (r = .79, %SEE = 28%).

Absorptiometry, Photon↗
PubMed1990

Normal age-related patterns of cellular and fatty bone marrow distribution in the axial skeleton: MR imaging study.

Knowledge of age-related distribution patterns of cellular and fatty marrow is critical to the interpretation of magnetic resonance (MR) imaging studies. To determine such patterns, the authors retrospectively evaluated 70 examinations each of the skull, cervical spine, thoracic spine, lumbar spine, pelvis, and proximal femur (420 examinations) in patients without known bone marrow abnormality who ranged in age from 6 months to older than 70 years. Two to four distinct patterns were identified in each anatomic area on spin-echo images obtained with a short repetition time and a short echo time. The relative frequency of the patterns for different age groups is consistent with the known physiologic conversion from cellular to fatty marrow with advancing age. Knowledge of these patterns should help in the interpretation of MR images of the axial skeleton.

Adult↗
PubMed1989

New radiographic grading scales for osteoarthritis of the hand. Reliability for determining prevalence and progression.

We developed and evaluated scales for grading the prevalence and progression of the individual radiographic features of osteoarthritis (OA) of the hand. Four equally time-spaced hand radiographs from 50 participants in the Baltimore Longitudinal Study of Aging, who were followed for at least 20 years, were read separately and "blindly" by 4 experienced, trained readers. Eleven hand joints were individually assessed for the presence of osteophytes, joint space narrowing, subchondral cysts, subchondral sclerosis, lateral deformity, and cortical collapse, and were also graded using the Kellgren/Lawrence scale, a global estimate of OA. The intraclass correlation coefficient was used to determine cross-sectional inter- and intrareader reliability. Interreader agreement on OA progression was evaluated using life-table analysis. Each of the grading scales for the individual radiographic features of OA of the hand, except for cysts, were cross-sectionally reliable between readers. Each reader was able to reproduce his original scores almost perfectly when grading the radiographs a second time. Using these scales, the different readers agreed on all the features of longitudinal progression of OA of the hand, except cysts. We believe that this method for grading hand radiographs for OA has proved to be reliable for both cross-sectional and longitudinal studies.

Adult↗
PubMed1989

Treated invasive cervical carcinoma. Utility of computed tomography in distinguishing between skeletal metastases and radiation necrosis.

The bony pelvis should be carefully evaluated on computed tomography (CT) scans of the lower abdomen and pelvis performed for staging cervical cancer or for evaluating suspected recurrence. CT provides optimal imaging of the spine and pelvis, frequently providing a clinically relevant supplement to bone scan or plain film information. In a study of eight patients with skeletal metastases from cervical carcinoma and three cases of radiation osteitis, overlap existed in their imaging characteristics. Metastases were always lytic but nearby sclerotic areas from radiation were often present. Radiation osteitis may be lytic, sclerotic, or mixed, and both may avidly accumulate bone-scanning radiotracers. The absence of a soft tissue mass, slow progression, blastic elements, and sharply defined borders on CT suggest radiation necrosis. However, in some lesions within a radiation portal, biopsy or MRI may be required for final diagnosis.

Bone Diseases↗
PubMed1988

Fracture nonunion: CT assessment with multiplanar reconstruction.

Nineteen patients with suspected or possible fracture nonunion underwent computed tomography (CT) with multiplanar reconstruction (MPR). Each case represented a difficult problem in fracture management in which clinical and conventional radiographic examinations had failed to provide a definitive diagnosis. CT with MPR demonstrated nonunion in 13 of 19 cases by delineating the lack of bone bridging across the fracture site in multiple planes. Variable amounts bridging were detected in six cases, indicating partial healing or delayed union. Evaluation of fracture healing with MPR was possible despite remaining metal hardware (ten cases), multiple operations (15 cases), or bone grafting (five cases). CT with MPR aided surgical planning and affected treatment options by providing a more detailed assessment of malalignment and angular deformities, the magnitude of the gap in bone, and the integrity of the adjacent weight-bearing joints in multiple projections. It is an important new modality for evaluating fracture nonunion.

Adult↗