Biomedical subjects

W R Reinus

Publications and source records attributed to W R Reinus.

At least 55 records · Page 3Linked to original sources

PubMed1994

MR imaging of bone marrow lesions: relative conspicuousness on T1-weighted, fat-suppressed T2-weighted, and STIR images.

OBJECTIVE: Fat-saturation pulse sequences offer important potential advantages for depiction of bone marrow lesions on MR images. The objectives of this study were to evaluate the relative conspicuousness of bone marrow lesions on images obtained by using two of the most widely available fat-suppression techniques, short-TI inversion recovery (STIR) and fat-saturation T2-weighted imaging, and to analyze the effect of these methods on image quality. In addition, we sought to determine if either or both of these sequences provide significant advantages relative to conventional T1-weighted spin-echo images for the evaluation of bone marrow lesions. SUBJECTS AND METHODS: T1-weighted (600/15 [TR/TE]), STIR (2500/20/160 [TR/TE/TI]), and fat-saturation T2-weighted (2500/20-70) MR images were obtained with a 1.5-T system in 34 consecutive patients with suspected bone marrow lesions. The conspicuousness of 36 lesions was evaluated subjectively by three radiologists, who also evaluated the MR images for how well they showed margination and extent of the lesion, image uniformity, motion artifacts, and overall image quality. In addition, lesion contrast on these sequences was compared quantitatively by using percentage contrast measurements. RESULTS: Lesions were qualitatively equally conspicuous with all four pulse sequences. Quantitative measurements indicated that lesions were more conspicuous on fat-saturation T2-weighted and STIR images than on T1-weighted images (p < .001). Differences between the first two sequences were not significant. Factors related to image quality, including reduction in motion artifacts and image uniformity, were generally superior on T1-weighted images. CONCLUSION: T1-weighted, fat-saturation T2-weighted, and STIR sequences all provide a high degree of sensitivity for depiction of most types of bone marrow abnormalities. Although the conspicuousness of lesions is similar on fat-saturation T2-weighted and STIR images, the former sequence has several practical advantages, including acquisition of more slices per unit time and improved tissue specificity. The combination of T1-weighted and either fat-saturation T2-weighted or STIR images is highly effective for the evaluation of bone marrow lesions.

Adolescent↗

PubMed1994

Emergency imaging of patients with resolved neurologic deficits: value of immediate cranial CT.

OBJECTIVE: The purpose of this study was to evaluate the utility of cranial CT performed emergently in patients with neurologic deficits of acute onset that had resolved by the time of presentation to an emergency department. MATERIALS AND METHODS: Data were evaluated from 1518 patients presenting to level I (967 patients) and level II (551 patients) emergency departments. All patients underwent cranial CT during their visit to the emergency department to exclude potential intracranial hemorrhage or life-threatening mass effect from other causes. Of the 1518 patients who had CT done in one of these two departments and were entered into this study, 71 had histories compatible with resolved neurologic deficits, including 62 with apparent cerebrovascular disease, six with trauma, and three with seizure. The data collected included demographic information, medical history, physical and neurologic examinations, relevant laboratory data, results of CT, and information regarding patients' disposition from the emergency department. RESULTS: All CT scans in patients with resolved deficits were normal except for one in a patient who had had trauma. The scan of this patient showed a left frontal bone fracture and a subtle underlying subdural hematoma. These required no therapy. The rate of abnormal findings on CT scans was significantly lower in the 71 patients in whom acute neurologic deficits had resolved than in the other 1447 patients who underwent CT for other reasons (chi 2: p < .001). CONCLUSION: Immediate cranial CT is not indicated in the evaluation of patients with resolved neurologic deficits, except possibly when the patient has a history of trauma.

Brain↗

PubMed1993

Prognostic features of Ewing sarcoma on plain radiograph and computed tomography scan after initial treatment. A Pediatric Oncology Group study (8346)

BACKGROUND: The authors studied the short-term changes in the plain radiographic and computed tomography (CT) appearance of Ewing sarcoma for indicators of decreased survival or future disease progression. METHODS: The authors evaluated CT scans and plain radiographs of the primary tumor site from 105 patients with Ewing sarcoma at diagnosis (prebiopsy), after induction chemotherapy (13 weeks), and after radiation therapy (20 weeks). RESULTS: Data suggest an association between postinduction CT findings of medullary involvement, cortical destruction, lysis, permeation, and unhealed pathologic fracture and decreased survival. On the postradiation scans, only medullary involvement was associated with worsened survival. No plain radiographic features were significant at any time. Absolute greatest tumor dimension was not significantly related to survival or tumor progression. The Cox model suggested that fractional change in greatest tumor dimension on CT at the time points studied relative to the prebiopsy CT was correlated to survival. Log-rank testing did not corroborate this finding. All significant associations appeared to result from adverse outcomes in small subgroups. CONCLUSIONS: Our data suggest that CT obtained immediately after induction chemotherapy and radiation may have some limited use in predicting the long-term prognosis of patients with Ewing sarcoma.

Actuarial Analysis↗

PubMed1993

Seizure patient selection for emergency computed tomography.

STUDY PURPOSE: We evaluated the need for emergency noncontrast cranial computed tomography (CT) among patients presenting to an emergency department with a complaint of seizure. METHODS: We retrospectively evaluated the medical records of 115 consecutive patients who presented to a trauma Level I ED with a complaint of seizure and underwent a noncontrast cranial CT. RESULTS: Sixty patients had a known seizure disorder, 38 had new-onset seizure, and 17 had possible seizure. The results of the neurologic examination and CT could be compared in 105 of the patients. An abnormal neurologic examination predicted 19 of 20 positive CT scans (95%) and demonstrated a strong association with CT results (P < .00004). Only a history of malignancy correlated to CT findings (P < .008). No other catalogued variable showed a statistical relationship with CT findings. CONCLUSION: Our data suggest that patients with either a history of malignancy or an abnormal neurologic examination at the time of examination in the ED will derive the greatest benefit from emergency CT.

Adolescent↗

PubMed1993

Practical selection criteria for noncontrast cranial computed tomography in patients with head trauma.

STUDY OBJECTIVE: To study patients with acute trauma retrospectively for clinical predictors of positive cranial computed tomography. METHODS: We reviewed the medical records and noncontrast computed tomography scans of 373 consecutive head trauma patients presenting to a trauma Level I emergency department. Potential criteria for patient selection were analyzed statistically, using both univariate and multivariate models. RESULTS: Our data suggest that relying on four variables--positive neurologic examination, intoxication, and a history of amnesia or focal neurologic deficit--as screening criteria for computed tomography would have saved 58.6% of the scans performed on these patients. Together, these criteria had a sensitivity of 90.1% and a negative predictive value of 98.1% for abnormal computed tomography. Four patients with positive scans would not have been detected using this strategy. None of these patients deteriorated clinically or required operative intervention. CONCLUSION: Our data suggest that it may be possible to effectively screen patients with head trauma for cranial computed tomography using clinical criteria and so reduce the current number of scans performed by more than half. However, a prospective study is required to confirm our results.

Adolescent↗

PubMed1993

Unenhanced emergency cranial CT: optimizing patient selection with univariate and multivariate analyses.

Charts from 1,074 consecutive emergency department patients who underwent cranial computed tomography (CT) were reviewed for predictors of a CT abnormality. Twenty-six clinical variables and the results of neurologic examination were compared with cranial CT findings. Patients with focal neurologic deficit, unresponsiveness, and hypertension had an increased risk of a CT abnormality. Blurred vision, trauma, loss of consciousness, headache, and dizziness were each associated with a lower risk of a CT abnormality. Multivariate analysis showed that only focal neurologic deficit and unresponsiveness effectively helped predict a CT abnormality. In patients with negative neurologic findings, only intoxication and amnesia were associated with greater than 10% positive scans and an increased risk for a CT abnormality. The data indicate that positive neurologic findings coupled with intoxication and amnesia would have helped detect 90.7% of the positive scans and provide an effective initial approximation strategy for selecting patients to undergo CT. Although 15 patients with positive scans (1.4%) would have been missed, this strategy would have yielded a negative predictive value of 97.3% and eliminated 53.9% of the CT scans obtained.

Brain Injuries↗

PubMed1993

Plasma cell tumors with calcified amyloid deposition mistaken for chondrosarcoma.

PURPOSE: To report cases of plasmacytoma with a radiologic appearance simulating that of chondrosarcoma. MATERIALS AND METHODS: The authors describe four cases of plasma cell tumors with scattered foci of calcification within their matrix, causing them to resemble chondrosarcoma radiographically. Histologic examination was performed in three of these cases. RESULTS: Biopsy specimens demonstrated that the calcification in these tumors was contained in areas of amyloid deposition. Although amyloid formation in association with plasma cell dyscrasias is well known, sufficient calcification within the amyloid to become radiographically identifiable has only rarely been reported. CONCLUSION: Calcification in amyloid produced by plasma cell tumors may at times simulate the appearance of chondrosarcoma.

Amyloid↗

PubMed1992

Plain radiographic predictors of survival in treated Ewing's sarcoma. IESS Committee.

We analyzed 16 radiographic features of primary Ewing's sarcoma in 342 patients from the IESS 7299 (Intergroup Ewing's Sarcoma Study) for prognostic significance. Of these, 3 features demonstrated a statistically significant relationship to survival: maximal tumor dimension, tumor location, and an appearance of honey-combing within the lesion. Those individuals with primary lesions centered in the pelvis, femur, or humerus had a worse survival rate than those with lesions centered elsewhere. Similarly, we observed an inverse relationship between the greatest dimension of the osseous portion of the lesion and survival. The radiographic finding of honeycombing also showed a statistical association with improved survival. However, this feature was observed infrequently, and its significance should be assessed further. Otherwise, no other feature that we analyzed showed any relationship to patient prognosis.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1992

Ultrasound evaluation of the common duct in symptomatic and asymptomatic patients.

We studied common duct (CD) diameter using real time ultrasound in 551 patients. The patients were divided into two groups: those referred for evaluation of the biliary tree [biliary-referred group (BRG)], and those referred for a problem unrelated to potential biliary tree pathology [non-biliary-referred group (NBRG)]. Potentially obstructed CDs were excluded from analysis. The CD diameter in the NBRG patients was found to increase after cholecystectomy (p less than 0.0003), but not in patients in this group with intact gallbladders and cholelithiasis. Dilation was observed in the BRG patients with either cholelithiasis (p less than 6 x 10(-7)) or cholecystectomy (p less than 4 x 10(-10)) compared to patients with intact gallbladders without cholelithiasis. To our knowledge, the former phenomenon has not been described in the literature. Our NBRG data suggest that the normal CD diameter should be set at 5 mm and 8 mm, respectively, for patients with intact gallbladders and patients post-cholecystectomy. No correlation was found between duct size and sex, age, or weight.

Adolescent↗

PubMed1988

Arthrography after total hip arthroplasty: utility of postambulation radiographs.

We compare pre- and postambulation arthrograms in 24 patients with total hip arthroplasty. In nearly half (42%) of these cases, the arthrographic evidence of a loosened prosthesis was more obvious after ambulation. Three patients (12.5%) had components which were normal by arthrographic criteria before walking, but were abnormal afterwards. We conclude that postambulation radiographs are valuable in patients who are examined for suspected loosening of prosthetic components.

Adult↗

PubMed1988

Arthrographic surface anatomy of the carpal triangular fibrocartilage complex.

In a review of 364 radiocarpal and 123 distal radioulnar joint arthrograms we identified 44 (12%) patients with contrast defects at either the proximal or distal surface of the carpal triangular fibrocartilage complex (TFCC). Differences in their arthrographic characteristics distinguished two separate groups of patients; one with similar and another with dissimilar appearing TFCC surface contrast collections. Thirty-one of our 44 patients had similar appearing, isolated radial-sided collections at either the proximal or distal TFCC surfaces. Our arthrographic, demographic, and historical study of these patients suggests that the collections are not caused by traumatic partial TFCC tears but represent a normal anatomic variant, probably a synovial recess at the radial TFCC attachment. Arthrography and dissection of a limited number of cadaveric specimens confirmed this conclusion. The second group included the remaining 13 patients. This group had contrast collections at either the proximal or distal TFCC surface, which varied in location and appearance. This smaller group is more likely to represent those uncommon patients with partial TFCC defects caused by tears.

Adolescent↗

PubMed1988

In vivo analysis of single, pre- and postprocessing quantitative CT techniques.

Measurements of bone mineral using single and dual-energy quantitative computed tomography (CT) are examined in vivo in 108 vertebral bodies scanned on a Siemens DRH scanner. Pre and postprocessing dual-energy techniques are compared. In the range of clinically useful kilovoltage, the choice of beam energy does not make a significant difference to the single-energy bone mineral measurement. Postprocessing dual-energy measurement in vivo shows a statistically significant decrease in the amount of mineral measured compared to single-energy measurements, whereas the preprocessing measurement shows a significant increase.

Adult↗

PubMed1987

Primary Ewing's sarcoma involving the bones of the head and neck.

Ewing's sarcoma is a rare tumor of the bone. In the Intergroup Ewing's Sarcoma Study (IESS) approximately 4% of the primary bone tumors arose in the bones of the head and neck. The mean age of patients was 10.9 years; boys slightly dominated the group. Signs and symptoms were local in distribution, with a mass or swelling most frequent. As in other sites, we categorized the dominant histologic pattern as diffuse or filigree, the latter carrying a more unfavorable prognosis. The radiographic appearance may be atypical as compared to Ewing's sarcoma at other sites. Prognosis of head and neck Ewing's is significantly better than Ewing's sarcoma overall. The gnathic bones were commonly affected, yet there was no associated mortality. No patient with primary disease in the bones of the head and neck who survived for 5 years on any of the IESS protocols has subsequently died.

Adolescent↗

PubMed1987

Arthrographic evaluation of the carpal triangular fibrocartilage complex.

One hundred sixty-two patients had analyses for correlation of triangular fibrocartilage abnormalities (TFCC), with duration and location of pain and other possible associated radiographic, scintigraphic, and arthrographic abnormalities. Results indicated that TFCC perforations did not correlate with any pain complex or other associated radiographic, arthrographic, or scintigraphic abnormality. No association with carpal instability or with ulnar variance could be identified. No definition between perforations that were posttraumatic and those that were the results of a degenerative process could be made. Several small defects on both the proximal and distal surfaces of the TFCC were identified. They do not appear to have been reported previously in the literature. Their significance is discussed.

Adult↗

PubMed1987

Posteroanterior wrist radiography: importance of arm positioning.

Proper interpretation of wrist radiography requires a standardized radiographic technique. We obtained posteroanterior (PA) radiographs of the wrist in nine patients in three different arm positions to study the effect of arm position on ulnar styloid process orientation. An appearance simulating a normal anteroposterior (AP) wrist radiograph was present in six of nine PA radiographs when the arm was positioned next to the trunk, and the elbow was flexed to a 90% angle. The orientation of the ulnar styloid was not helpful in differentiating either pronated from supinated wrist positions or AP from PA projections. We concluded that radiographic screening of the carpus should be performed with standardized wrist positioning and nomenclature as described in modern radiographic technological texts. Supplemental projections should be exposed and interpreted with an understanding of the position of the arm and the direction of the incident radiographic beam at the time of examination.

Arm↗

PubMed1987

Two postprocessing CT techniques for determining the composition of trabecular bone.

Two dual-energy CT techniques have been developed to analyze the mineral and fat content of trabecular bone. Both are postprocessing techniques that employ calibration standards. Experiments were performed to test these techniques against conventional single-energy techniques and two other dual-energy techniques. As expected, all of the dual-energy methods estimate the mineral content more accurately when fat is present. In contrast to the other dual-energy methods, the new methods described in this article are unique because they make a separate estimate of the fat content of the bone. The results of preliminary tests of these techniques in estimating fat content have been encouraging. Although not exact, the estimates show the correct trend in increasing proportionately as the fat content increases. Possible applications of the techniques in the study of osteoporosis and other bone diseases are described.

Adipose Tissue↗

PubMed1987

Improved accuracy of single-energy computed tomography bone mineral determination using threshold analysis.

Single-energy CT for bone-mineral determination underestimates the degree of mineralization because of error caused by fat in the marrow space. A correction using set theory and threshold analysis was developed to reduce this error. Corrections between 4.7% and 130.9% of fat-induced error are observed. The amount of correction is related directly to the amount of osteopenia present, and is patient specific. This technique may be appropriate for clinical evaluation because the major application of quantitative CT (QCT) is for bone mineral analysis in a population with increasing marrow space fat over time. This technique may allow reduction of the uncertainty of normal data developed using single energy QCT, thereby making the technique more sensitive to early detection of osteopenia.

Adipose Tissue↗

PubMed1987

Fluoroscopic identification of torn intercarpal ligaments after injection of contrast material.

Wrist arthrography is often used to evaluate the integrity of the scapholunate and lunotriquetral ligaments. This may be difficult when the ligaments are obscured by contrast material in standard radiographic projections, despite filming under fluoroscopic observation during the injection of contrast material. When superimposition occurs, we recommend fluoroscopic positioning of the wrist to optimally visualize the individual ligaments in profile. We applied this technique in performing 240 wrist arthrograms, 88 (37%) of which had scapholunate and/or lunotriquetral ligament tears. As a result, a definite diagnosis of the specific site of ligamentous disruption was possible in all but one case. Using this technique, we also identified six short-segment or "pinhole" ligamentous tears. Identification of commonly interrupted ligaments in profile by using fluoroscopy after contrast material has been injected may allow identification of specific ligamentous disruptions or short-segment tears, as well as a diagnosis of a specific anatomic abnormality that otherwise would not be possible.

Arthrography↗