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Biomedical subjects

D H Feiglin

Publications and source records attributed to D H Feiglin.

At least 19 recordsLinked to original sources

Bone marrow reconversion in adults who are smokers: MR Imaging findings.

OBJECTIVE: Conversion of bone marrow in the extremities from red to yellow is a normal maturation process. Marrow reconversion is present when expected yellow marrow is replaced with active red marrow, and it tends to occur at times of physiologic stress. The significance of this finding on MR imaging is not always clear. Accordingly, we studied the prevalence of bone marrow reconversion in adults undergoing MR imaging of the knee for reasons other than marrow disorders. Possible relationships between marrow reconversion and age, sex, weight, and smoking were sought. MATERIALS AND METHODS: Fifty-nine outpatients over 24 years of age who had no evidence of hematopoietic disorders and for whom MR images of the knee were available for review were selected for study. Patients younger than 25 years old were eliminated to ensure that all patients in the study were old enough to have achieved normal adult marrow conversion. The 59 subjects were classified according to their smoking histories. Twenty-eight were nonsmokers, 10 were intermediate smokers, and 21 were heavy smokers. The MR images were classified as showing either red marrow (reconverted from yellow to red) or yellow marrow (converted) by two independent observers who had no knowledge of the patients' smoking histories. RESULTS: MR images of six heavy smokers, two intermediate smokers, and one nonsmoker showed evidence of reconversion. A statistically significant association between marrow reconversion and heavy smoking (p = .02) was found. Reconversion also was found to be more prevalent in patients less than 39 years old and in obese women who smoked. No association was found between weight, sex, or obese male smokers and reconversion. CONCLUSION: Our results show marrow reconversion at the knee is most prevalent in heavy smokers, younger patients, and especially obese women who smoke heavily. In these patients, marrow reconversion can be a normal finding on MR imaging. In other patients, other causes should be considered.

Adult

Generation of parametric images during routine Tc-99m PYP inhalation/Tc-99m MAA perfusion lung scintigraphy. Technical note.

A simple technique is described for generating ventilation/perfusion ratio and perfusion/ventilation ratio images from the posterior Tc-99m PYP aerosol inhalation and Tc-99m MAA perfusion images obtained during routine lung scintigraphy. These images highlight areas of ventilation/perfusion incongruence--mismatch or reverse mismatch--that may sometimes be difficult to detect on conventional images.

Aerosols

Multiplane gallium tomography in assessment of occupational chest diseases.

Gallium-67 scintigraphy is helpful in the evaluation of inflammatory, respiratory diseases. Single-photon emission computed tomography (SPECT) provides three-dimensional tomographic reconstruction of radioisotope distribution in the body. The addition of SPECT to gallium-67 scanning in 27 patients demonstrated an improvement in the sensitivity for detecting the presence and extent of interstitial occupational lung disease. This technique may provide earlier detection of parenchymal lung changes than can the chest x-ray and planar scanning in some patients with asbestosis. Findings in six patients with asbestosis are reported.

Adult

Magnetic resonance imaging of a third trimester abdominal pregnancy.

Abdominal pregnancies are rare, representing 1% of all ectopic pregnancies. Early and accurate diagnosis is essential in order to avoid the serious complications associated with the condition, including catastrophic hemorrhage secondary to placental separation. The clinical presentation of abdominal pregnancy is extremely variable and physical examination by itself may be insufficient for diagnosis. Ultrasound (US) is currently the imaging method of choice for establishing gestational location, but sonographic interpretation may be difficult due to gas within the gastrointestinal tract and distorted pelvic anatomy. The use of magnetic resonance imaging (MRI) in obstetric diagnosis, including abdominal pregnancy, has been described. We report a case of an abdominal pregnancy of 32 wk gestation diagnosed by MRI.

Adult

Quantitation of abnormal 67Ga uptake in pulmonary interstitial vascular disease--a new test to detect diffuse lung disease.

Gallium 67 has been used as a modality to diagnose and follow the clinical course of diseases such as tumors, infections, inflammatory disorders, and interstitial lung disease. It has been appreciated, however, that mild to moderate changes in scan activity, when these disorders are followed over time, are less than optimal. SPECT (single-photon emission computed tomography) scanning is a new technique designed to obviate this problem. SPECT scanning utilizes computer acquisition to provide three-dimensional scanning and the additional benefit of colorization to aid in discerning differences of uptake. SPECT scanning was performed on 22 patients with interstitial lung disease of various etiologies. Additionally, 7 patients had follow-up SPECT scanning to determine their response to treatment. Two patients are presented as examples.

Female

Multimodality approach to osteonecrosis of the femoral head.

Treatment of osteonecrosis of the femoral head appears to be effective when the disease is identified and treated early. Forty-one patients were evaluated with prospective laboratory assessment, anteroposterior and frog-lateral roentgenograms of both hips, intraosseous pressure measurements (IOP), magnetic resonance imaging (MRI), and 99mTc methylene diphosphonate planar and single-photon emission computerized tomographic (SPECT) bone imaging. Pathologic specimens were obtained in most patients. Preradiographic disease was identified in 26 hips and 11 of these were asymptomatic. Fifteen clinically symptomatic hips had normal plain roentgenograms, but abnormal protocol studies. Evaluation of sensitivity, specificity, and predictive value (positive and negative), respectively, in diagnosing osteonecrosis of the femoral head revealed the following percentages: 83%, 83%, 96%, and 48% for planar bone scanning; 91%, 78%, 94%, and 70% for SPECT; 87%, 83%, 96%, and 55% for MRI; 80%, 60%, 95%, and 25% for IOP; and 88%, 100%, 100%, and 25% for core biopsy. (There were few true negatives, thus specificity values are approximations.) The identification of preradiographic stages is possible, but difficult. MRI appears appealing at present, particularly in identifying disease in asymptomatic hips. However, there is no definitive method for noninvasive diagnosis. Pathologic confirmation in early stages is difficult.

Adolescent

Allograft reconstruction of the acetabulum during revision total hip arthroplasty. Clinical, radiographic, and scintigraphic assessment of the results.

In twenty-one hips of twenty-one patients, the acetabulum was reconstructed using allografts during revision of a total hip arthroplasty. The patients' average age at the time of revision was 64.3 years (range, nineteen to eighty-six years). At an average follow-up of 3.5 years (range, two to five years), three patients had died of causes unrelated to the hip reconstruction, and one had been lost to follow-up. In the other seventeen, the average Harris hip rating was 89 points (range, seventy to 100 points) at follow-up. In one patient the allograft collapsed, so that revision was required. Two patients had asymptomatic progressive radiolucencies at the cement-bone interface of the reconstructed acetabulum, and another had a 1.5-millimeter-wide lucency at the interface of the donor and recipient bone but was asymptomatic, and there had been no change in the position of the cemented acetabular component since operation. The remaining grafts appeared to be incorporated securely, as determined by radiographic examination. Three-dimensional computerized tomographic radioisotopic bone scans showed uniform uptake, consistent with revascularization and new-bone formation, in all grafts. There was no radiographic evidence of focal avascularity and there were no infections. Femoral-head bone allografts appear to provide a useful technique for the reconstruction of a severely deficient acetabulum during revision total hip arthroplasty.

Acetabulum

Magnetic resonance imaging of musculoskeletal infections.

In summary, MRI has a high sensitivity for the detection of inflammatory disease involving the musculoskeletal system. Because of the usual anatomic pattern of involvement in the vertebral column, there is also a high specificity. In the appendicular skeleton and pelvis, it is unclear whether MRI can add to the sensitivity and specificity of radionuclide studies in uncomplicated cases of acute infection. However, it can be performed more rapidly and provides greater anatomic detail and delineation of the extent of marrow involvement than radionuclide studies. MRI can be used in both acute and chronic osteomyelitis to guide a diagnostic interventional test to the appropriate site. It is capable of excluding involvement of the medullary canal, and it is better than radionuclide studies for differentiating soft tissue infection with periostitis from osteomyelitis. It has only a limited role in the immediate postoperative period, and in the presence of metallic implants, an indium-labeled leukocyte scan may be more appropriate. Finally, it must be remembered that the current data base of MRI is small and that further refinement of its role in the evaluation of inflammatory processes will be forthcoming.

Adult

Gated cardiac magnetic resonance structural imaging: optimization by electronic axial rotation.

Most magnetic resonance imaging has used body orthogonal axes with the Z axis placed along the length of the body and the X and Y axes at right angles to the body. This orientation is not optimum for the heart; visualization of sections along the short and long cardiac axes would best define cardiac structural detail and functional status. The new orientation was accomplished by selection of electronic angulation of the magnetic fields for each subject rather than by attempting to approximate the cardiac axes by altering the position of the patient. This technique improved visualization of comparative wall segments, valvular structures, and the true four-chamber view of the heart, and also gave the best visualization of the pericardium. In addition, more accurate estimates of chamber size and myocardial mass can be made from the short-axis orientation, since the sections are orthogonal to the myocardium.

Cardiomegaly

Vertebral osteomyelitis: assessment using MR.

Thirty-seven patients who were clinically suspected of having vertebral osteomyelitis were prospectively evaluated with magnetic resonance (MR), radiography, and radionuclide studies. These findings were correlated with the final clinical, microbiologic, or histologic diagnoses. Based on the results of these latter studies, 23 patients were believed to have osteomyelitis. MR examinations consisted of at least a sagittal image (TE = 30 msec, TR = 0.5 sec) and an image obtained at TE = 120 msec, TR = 2-3 sec. All patients underwent radiographic and MR examinations, 36 underwent technetium 99m-HDP bone scanning, and 20 patients underwent gallium 67 scanning. Nineteen patients underwent both bone and gallium scanning. The imaging studies were reviewed independently by investigators blinded to the final diagnoses. MR had a sensitivity of 96%, specificity of 92%, and accuracy of 94%. Combined gallium and bone scan studies (19 cases) had a sensitivity of 90%, specificity of 100%, and accuracy of 94%. Bone scans alone had a sensitivity of 90%, specificity of 78%, and accuracy of 86%. Plain radiographs had a sensitivity of 82%, specificity of 57%, and accuracy of 73%. The MR appearance of vertebral osteomyelitis in this study was characteristic, and MR was as accurate and sensitive as radionuclide scanning in the detection of osteomyelitis.

Adult

Comparison of gated cardiac MRI and 2D echocardiography of intracardiac neoplasms.

The gross diagnostic factors of intracardiac tumor in four patients imaged by two-dimensional echocardiography (2D echo) and magnetic resonance imaging (MRI) were compared. Three cases had left and one had a right atrial tumor, all histologically identified as myxoma. Gated cardiac MRI depicted the size, shape, and surface characteristics of the tumors more clearly than 2D echo, because MRI provides better spatial and contrast resolution. Depiction of tumor attachment was poor to good with both techniques. Both techniques were highly accurate in localizing the tumor and displaying whether it was fixed or mobile. The global field of view provided by MRI allows better definition of tumor prolapse, secondary valvular obstruction, and cardiac chamber size. This study shows that despite its early stage of development, gated cardiac MRI provides superior image quality and is complementary to 2D echo for characterization and diagnosis of intracardiac tumor.

Adult

Clinical evaluation of 360 degrees and 180 degrees data sampling techniques for transaxial SPECT thallium-201 myocardial perfusion imaging.

The most serious controversy regarding the application of transaxial SPECT technology to 201Tl myocardial perfusion imaging is the choice between 360 degrees compared with 180 degrees data sampling techniques. The present study utilized the original 360 degrees sampled raw data of 25 patients who had both SPECT 201Tl myocardial perfusion imaging and coronary angio/ventriculography for back projection reprocessing to accomplish the 360 degrees/180 degrees comparison. The results show a high incidence, 36% (9/25), of false-positive segmental perfusion abnormality and a high incidence, 24% (6/25), of moderate to severe degree of image distortion with the 180 degrees data sampled reconstructed images. These were not observed in the 360 degrees data sampled reconstructed images. The above findings confirmed our previous preliminary conclusion that even though the 180 degrees data sampling technique has the advantage of providing improved image contrast and reduction in acquisition time it is not a reliable technique and should be abandoned. The 360 degrees data sampling is the technique of choice for transaxial SPECT 201Tl myocardial perfusion imaging.

Adult

Radionuclide angiography and endomyocardial biopsy in the assessment of doxorubicin cardiotoxicity.

Thirty-eight patients with a mean age of 53.2 years (19 to 75 years of age), who were receiving doxorubicin (D) for malignant disease, were studied in order to determine the relationship between functional and morphologic myocardial changes at different dose levels. Serial patient evaluations included physical examination, chest x-ray, electrocardiogram (ECG), endomyocardial biopsy (EMB), and rest-exercise gated nuclear angiography (GNA), at doses of D ranging from 144 to 954 mg/m2 (mean, 426 mg/m2). Physical examination, chest x-ray, and ECG proved to be insensitive predictors of D cardiotoxicity. Correlation of GNA and EMB in 31 patient evaluations, exclusive of known heart disease, did not reveal any false-positive angiograms, and all abnormal GNAs were associated with abnormal biopsies. Use of stress GNA uncovered six abnormal ventricles which could have been missed with a rest GNA alone. It has been suggested that: (1) GNA is a reliable monitor of D therapy; (2) an exercise study should be performed when the rest ejection fraction is normal, but is unnecessary when the rest EF is abnormal; (3) all patients with a resting ejection fraction of less than 45%, exclusive of other cardiac disease, should have D discontinued; and (4) endomyocardial biopsy is useful in assessing D cardiotoxicity in patients with other possible causes of an abnormal GNA.

Adult

The "hot" patella.

Increased patellar uptake on bone scans is seen quite commonly but the possible or probable etiologies of this finding have not been previously well described. A review of 100 consecutive bone scans showed that the incidence of bilateral "hot" patellae is 15%. Identified etiologies include osteoarthritic degenerative disease (35%), fracture, possible metastatic disease, bursitis, Paget's disease, and osteomyelitis. The value of careful history, physical examination, and radiographs is stressed.

Adult

Left ventricular function in trained and untrained healthy subjects.

Left ventricular function was compared in 18 normal sedentary controls (mean age 28 years, range 22 - 34 years) and nine endurance-trained athletes (mean age 19 years, range 15 - 25 years) at rest and during supine bicycle exercise. Gated radionuclide angiocardiograms were performed at rest and at each level of graded maximal supine bicycle exercise. Heart rate, blood pressure, left ventricular ejection fraction and the relative changes in left ventricular end-diastolic and end-systolic volumes were assessed. Athletes attained a much greater work load than controls (mean 22.1 kpm/kg body weight vs 13 kpm/Kg body weight). Both groups achieved similar increased in heart rate, blood pressure and ejection fractions. In the controls, the mean end-diastolic volume increased to 124% of that at rest (p less than 0.02) during exercise and the mean end-systolic volume decreased to 81% of the rest level (p less than 0.02). In contrast, the mean end-diastolic volume did not significantly change during exercise in the athletes, and the mean end-systolic volume decreased to 64% of rest (p less than 0.05). Thus, although trained and untrained healthy subjects had similar increases in the left ventricular ejection fraction during exercise, different mechanisms were used to achieve these increases. Untrained subjects increased end-diastolic volumes, whereas trained subjects decreased the end-systolic volumes. The ability of athletes to exercise without increasing preload may be an effect of training amd might have important implications in reducing myocardial oxygen demand during exercise.

Adult