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W R Reinus

Publications and source records attributed to W R Reinus.

At least 37 records · Page 2Linked to original sources
PubMed1996

Doubling skeletal mass during adult life: the syndrome of diffuse osteosclerosis after intravenous drug abuse.

A former intravenous substance abuser, seropositive for hepatitis C virus infection, was referred for diffuse osteosclerosis. There was no history of fracture or skeletal deformity. Cortical and trabecular bone density was approximately twice the mean value for controls. Skeletal histology revealed dense lamellar bone. Recognized causes of acquired generalized osteosclerosis or hyperostosis were excluded. This patient verifies the syndrome of painful diffuse osteosclerosis after intravenous drug abuse and shows that skeletal mass can be markedly increased with histologically normal, structurally sound bone during adult life. Elucidation of the etiology and pathogenesis could offer an effective treatment for osteoporosis.

Absorptiometry, Photon↗
PubMed1996

Prospective optimization of patient selection for emergency cranial computed tomography: univariate and multivariate analyses.

RATIONALE AND OBJECTIVES: To determine if the clinical variables that are important for selecting patients for emergency cranial computed tomography (CT) are population dependent. METHODS: Prior to obtaining scans, physicians working in an emergency department in a level II trauma center completed a form describing the indication for the CT examination. These data were matched to the CT scan results and analyzed statistically using univariate and multivariate methods. These results were compared with a prior study at a level I trauma center. RESULTS: Of 551 patients having cranial CT, neurologic examination was positive in 340 and CT scan was positive in 122. The neurologic examination correlated strongly with the results of the CT scan (P < 0.00001). In this patient population, the most important clinical predictors of 17 abnormal CT scans from the 211 patients without positive neurologic examinations were seizure and a history of neoplasm. These high-yield variables differ from our prior retrospective study in which intoxication and amnesia were the important predictors in patients with negative examinations. The difference in predictors between the populations most likely results from different prevalences of trauma and ischemic disease. CONCLUSIONS: Abnormal neurologic examination is the most important criterion available to select patients for emergency cranial CT. Other variables (eg, seizure, amnesia, intoxication, and history of neoplasm) that help select patients without neurologic findings appear to be population dependent.

Brain↗
PubMed1995

Lead arthropathy: a cause of delayed onset lead poisoning.

Patients who suffer gun shot wounds often have retained bullet fragments within their bodies. These are usually of no clinical consequence. We describe three patients with retained bullets within their hip joints. One of these patients, who had extensive ground intra-articular bullet fragments and secondary osteoarthritis of the hip, presented with signs, symptoms, and laboratory data consistent with lead intoxication. The bullet and metallic fragments were removed surgically with good clinical response. Two patients whose bullets were implanted entirely within the femoral head and whose joints showed smaller degrees of lead fragmentation had no symptoms of lead intoxication. The degree of intra-articular fragmentation of the bullet and the surface area of lead exposed to synovial fluid are emphasized as decisive factors with respect to appropriate therapy.

Aged↗
PubMed1995

Artificial neural networks for screening patients needing emergency cranial computed tomography scans in emergency departments.

RATIONALE AND OBJECTIVES: We evaluated the potential for a neural network to screen candidates for emergency cranial computed tomography (CT) scans in an emergency department setting. METHODS: Data were collected from 1625 patients undergoing emergency cranial CT scanning in two different emergency departments (EDs). Singular value decomposition (SVD) was used to remap input data for network training. Data were randomly divided into six subsets, and one was reserved as a test set to analyze network performance. Five networks were then trained on data from the five remaining sets using fivefold cross-validation. Each trained network was allowed an independent vote on need for CT scanning in each case from the test set. The majority vote was used as the final prediction. A similar analysis was done on data from each individual ED. Results are compared with prior statistical studies of the same data. RESULTS: The network performed well when predicting clinical variable patterns that consistently produced negative CT scans and on patterns that were ambiguous in terms of the CT scan results. It performed poorly, however, on patterns that consistently predicted positive scans. This last finding appears to have resulted from inadequate training material. The two populations from which data were taken were shown to be distinct, but a network trained on the combined data performed as well as the networks from the individual EDs in predicting patients requiring CT scanning. Variables with the greatest contribution to the networks' prediction were consistent with those in prior statistical studies. CONCLUSION: Although preliminary in nature, neural networks show promise as a screening device for selecting patients for emergent cranial CT scanning.

Analysis of Variance↗
PubMed1995

Quantitative analysis of solitary lesions of bone.

RATIONALE AND OBJECTIVES: To quantitate the radiographic features of common solitary lesions of bone using vector analysis to optimize their radiographic description. METHODS: Plain radiographs of 709 solitary bone lesions were reviewed. Relevant demographic, anatomic, and structural data were cataloged. These data were used to approximate the vector space defined by all possible solitary lesions of bone. Vector space analysis on the entire set of lesions was performed to determine similarities among and between lesion types. RESULTS: The 709 lesions generated 614 separate vectors within the appearance vector space. Only 10 vectors were represented more than 3 times, indicating great variability among and between most lesion types. Osteochondromas (with two vectors repeated 10 and 15 times, respectively) and peripheral chondrosarcomas (with one vector repeated 5 times) were relatively uniform in appearance. Gender bias was present for multiple types of lesions. Larger lesions that involved more than one anatomic center were more likely to be malignant. Lesions occurring in the femoral diaphysis and pelvic flat bones were statistically more likely to be malignant. CONCLUSIONS: Analysis shows that most lesions have highly varied vectors in the appearances within the vector space. More in-depth analysis of each lesion type using this quantitative technique is required to better define individual lesion subspaces and hence their radiographic appearances with respect to other bone lesions.

Bias↗
PubMed1995

Quantitative analysis of the plain radiographic appearance of aneurysmal bone cysts.

RATIONAL AND OBJECTIVES: To quantitate radiographic features that distinguish the plain radiographic appearance of aneurysmal bone cyst (ABC) from other solitary lesions of bone. MATERIALS AND METHODS: Seven hundred nine cases of focal bone lesions, including 32 ABCs were analyzed according to demographic, anatomic, and plain radiographic features. Vector analysis of groups of features was performed to determine those that are most sensitive and specific for the appearance of ABC in contrast with other lesions in the data base. RESULTS: Aneurysmal bone cysts most consistently are medullary-based, either eccentric or centric (94%), show lysis (100%), cortical thinning (97%), enlargement of the host bone (100%), and geographic bone destruction (94%). They have well-defined edges (84%), no fallen fragment (100%), no evidence of periosteal reaction (75%), and no visible matrix (91%). Although they typically occur in the metadiaphysis of long bones, the anatomic location and demographic data did not significantly affect the sensitivity or specificity for detection of ABCs. The vector analysis-generated differential diagnoses include giant cell tumor, unicameral bone cyst, nonossifying fibroma, enchondroma, and fibrous dysplasia as the major lesions.

Adolescent↗
PubMed1995

Quantitative analysis of the plain radiographic appearance of central chondrosarcoma of bone.

RATIONALE AND OBJECTIVE: To quantitate radiographic features that distinguish the plain radiographic appearance of central chondrosarcoma from other solitary bone lesions. MATERIALS AND METHODS: Seven hundred nine cases of focal bone lesions, including 37 central chondrosarcomas, were analyzed according to demographic, anatomic, and plain radiographic features. Vector analysis of groups of features was performed to determine those that are most sensitive and specific for the appearance of central chondrosarcoma in contrast with other lesions in the data base. RESULTS: The most specific appearance of long bone central chondrosarcomas was a lesion within the medullary cavity with geographic destruction, containing calcified matrix and a diameter greater than 5.9 cm, or arising within the proximal metaphysis or diaphysis. These features all are present in 9 (39%) of the 23 long bone central chondrosarcomas and in less than 1% of other lesions. In flat bone lesions, calcified matrix and either geographic bone destruction, medullary location, or enlargement of the host bone were 100% specific but of low sensitivity, identifying 7 (50%), 7 (50%), and 6 (41%) of the 14 flat bone chondrosarcomas, respectively. Inclusion of calcified matrix in the description is essential to make the criteria specific but excludes several of the most aggressive long bone chondrosarcomas. The vector analysis-generated differential diagnosis include osteosarcoma, fibrous dysplasia, unicameral bone cysts, aneurysmal bone cysts, malignant fibrous histiocytoma, and Ewing sarcoma. CONCLUSIONS: A relatively specific set of radiographic features can be defined to assist in plain film diagnosis of central chondrosarcoma, but there are many chondrosarcomas that fall outside these parameters. Thus, while not sufficiently sensitive to allow accurate plain film diagnosis in all cases, these criteria serve as an improved foundation for differential diagnosis.

Adolescent↗
PubMed1995

Quantitative analysis of the plain radiographic appearance of eosinophilic granuloma.

RATIONALE AND OBJECTIVES: To quantitate features that distinguish the plain radiographic appearance of eosinophilic granuloma (EG) from other solitary lesions of bone. MATERIALS AND METHODS: Seven hundred nine focal bone lesions, including 26 EGs, were analyzed according to demographic, anatomic, and plain radiographic features. Vector analysis of groups of features was performed to determine those that are most sensitive and specific for the appearance of EG in contrast to other lesions in the data base. RESULTS: The radiographic appearance of EGs was most consistently that of a medullary based lytic lesion (100%) with geographic destruction (76.9%), lobular contour (73.1%), and well-defined edges (73.1%). Long bone lesions showed these features more frequently than EGs in other locations. Periosteal reaction was visible in all long bone lesions but in only one nonlong bone lesion (5.9%). Characterization of EG in long bones as a lytic, medullary-based metaphyseal or diaphyseal lesion with geographic destruction, lobular contours, periosteal reaction, no matrix, and no subarticular extension showed a sensitivity of 55.6% of EG and prevalence of 22.7%. The vector analysis-generated differential diagnoses include unicameral bone cyst, aneurysmal bone cyst, giant cell tumor, Brodie's abscess, enchondroma, chondrosarcoma, and malignant fibrous histiocytoma. CONCLUSIONS: The radiographic appearance of EG is relatively nonspecific but, using vector analysis, can be better elucidated than in current textbook descriptions.

Adolescent↗
PubMed1995

Quantitative analysis of the plain radiographic appearance of nonossifying fibroma.

RATIONAL AND OBJECTIVES: To quantitate radiographic features that distinguish the plain radiographic appearance of nonossifying fibroma (NOF) from other solitary lesions of bone. MATERIALS AND METHODS: Seven hundred nine cases of focal bone lesions, including 34 NOFs, were analyzed according to demographic, anatomic, and plain radiographic features. Vector analysis of groups of features was performed to determine those that are most sensitive and specific for the appearance of NOF in contrast to other lesions in the data base. RESULTS: The radiographic appearance of NOFs was most consistently a medullary based (97%), lytic lesion (100%) with geographic bone destruction (100%), marginal sclerosis (97%), and well-defined edges (94%). A statistically significant number of lesions were located in the distal aspect of long bones. Unicameral bone cyst shared the most radiographic features with the NOF. Vector analysis showed a large degree of overlap between NOF and other lesions such as aneurysmal bone cyst, chondromyxoid fibroma, and eosinophilic granuloma. The description that optimized sensitivity and prevalence for detection of NOF is a medullary based, ovoid lesion in the distal or proximal portions of a long bone with well-defined edges, a partial or complete rind of sclerosis, and absence of fallen fragment, periosteal reaction, and cortical disruption. CONCLUSION: The radiographic appearance of NOF is relatively nonspecific but, using vector analysis, can be better elucidated over current textbook descriptions.

Adolescent↗
PubMed1995

MR diagnosis of rotator cuff tears of the shoulder: value of using T2-weighted fat-saturated images.

OBJECTIVE: The purpose of this study was to compare the use of fat-saturated T2-weighted spin-echo MR imaging with that of conventional T2-weighted spin-echo MR imaging to detect full- and partial-thickness tears of the rotator cuff of the shoulder, using arthroscopy as the standard for the diagnosis. SUBJECTS AND METHODS: Forty-nine consecutive patients with shoulder pain who had both MR imaging and arthroscopy of their affected shoulders were studied. The study group consisted of 10 patients with full-thickness tears of the rotator cuff, 20 with partial-thickness tears of the rotator cuff, and 19 with intact rotator cuff tendons proved arthroscopically. All patients had T1-weighted, conventional T2-weighted, and fat-saturated T2-weighted MR images obtained in a plane slightly oblique to the coronal plane along the long axis of the supraspinous tendon. The images were divided into two sets, one including both T1-weighted and conventional T2-weighted images, the other including T1-weighted and fat-saturated T2-weighted images. Two musculoskeletal radiologists reviewed each set of MR images in a blinded fashion. The reviewers were asked to decide whether the rotator cuff showed a full-thickness tear, a partial-thickness tear, or no tear on each set of images. In the case of partial-thickness tears, the reviewers were asked to indicate which surface (bursal or joint) of the rotator cuff was affected. These data were correlated with the arthroscopic findings and with each other using McNemar and kappa analysis. RESULTS: Detection of full-thickness tears was excellent for both reviewers using either imaging technique. However, when the fat-saturated technique was used, the sensitivity increased significantly, from 80% to 100%. Detection of partial-thickness tears was poor with conventional spin-echo MR imaging (15%). Although significantly improved when fat saturation was used (35%), detection rates were still lower than rates reported in the literature. Identification of the torn surface of the rotator cuff was correct in 50% of cases in which partial-thickness tears were successfully identified. Fat saturation decreased the specificity of identification of both partial and full-thickness tears of the rotator cuff but significantly increased the specificity with which intact rotator cuffs were identified. CONCLUSION: Use of the fat-saturation technique improved detection of both full-thickness and partial-thickness tears of the rotator cuff on MR images compared with standard spin-echo imaging techniques. Despite this improvement, detection of partial-thickness tears was poor with both techniques. Furthermore, correct identification of which surface of the rotator cuff was torn in patients with partial tears was nearly random.

Adult↗
PubMed1994

Ultrasonographic evaluation of the biliary tree in patients with atypical chest pain.

We studied the use of gallbladder ultrasonography in the evaluation of atypical chest pain (ACP). During an 8-month period, 52 patients were referred for biliary ultrasonography with a chief complaint of chest pain. Twelve (32.1%) had cholelithiasis discovered by ultrasonography. Four of these 12 (33.3%) underwent subsequent cholecystectomy with complete relief of symptoms. None of the patients with normal ultrasonography for whom follow-up was available (32) underwent subsequent cholecystectomy. We found no statistical difference in the prevalence of cholelithiasis between the ACP group and 85 asymptomatic controls. Clinical evidence confirms the concept that ultrasonography may play an important role in the evaluation of ACP.

Chest Pain↗
PubMed1994

Prognostic features of Ewing's sarcoma on radionuclide bone scan after initial treatment.

OBJECTIVE: To study short-term changes in the radiopharmaceutical bone scan (BS) appearance of Ewing's sarcoma for indicators of decreased survival or future disease progression. METHODS: One-hundred and four patients with non-metastatic Ewing's sarcoma were evaluated at three time points: time of diagnosis (pre-biopsy), after induction chemotherapy (13 weeks) and after radiation therapy (20 weeks). Radiographs, computed tomograms (CTs) and BSs were obtained at each interval. Primary lesion activity and size on BS were evaluated and compared to radiographic and CT findings. RESULTS: No significant relationship was found at any time point between absolute radiopharmaceutical activity within the primary lesion and either disease progression or patient survival. Relative changes in BS activity between time points were also not significantly related to disease progression or survival despite a significant decrease in activity among the three time points. The size of the BS abnormality compared to the CT abnormality at the primary lesion site was related to both survival and disease progression at the post-induction chemotherapy time point (P = 0.025 and P = 0.014, respectively) with larger BS abnormalities indicating worse prognosis and survival. This relationship lost its significance at the post-radiation time point. No other significant relationship between the relative size of the BS abnormality and the size of the plain radiographic or CT abnormality was detected. CONCLUSION: Our data suggest that BS imaging of the primary lesion of Ewing's sarcoma provides little information in terms of predicting long-term survival or disease progression in patients with non-metastatic Ewing's sarcoma.

Adolescent↗
PubMed1994

Evaluation of fat saturation technique for T2-weighted MR imaging of the spine.

The objective of this study was to evaluate the use of fat saturation for performance of T2-weighted imaging of the spine. Eighteen consecutive patients underwent MR imaging of the cervical (n = 7) or lumbar (n = 11) spine with proton density/T2-weighted sequences (TR 2200 ms, TE 30/80 ms) performed with and without fat saturation. Quantitative and qualitative analysis of images was conducted to compare tissue contrast, myelographic effect, presence of artifacts, and ability to delineate important anatomic structures on conventional and fat suppressed sequences. Images obtained with fat saturation demonstrated improved myelographic effect and increased contrast between vertebral body and disk, and between CSF and nerve roots/spinal cord. Image quality and most artifacts were equal on both sequences, though fat suppressed images had reduced image uniformity. Quantitative measurements of tissue contrast indicated improved contrast between vertebral bodies and CSF, disk, and spinal cord/nerve roots on fat saturation images.

Adult↗
PubMed1994

Clinical prediction of emergency cranial computed tomography results.

STUDY PURPOSE: To determine the ability of clinicians to predict the results of emergency head computed tomography (CT) scans. METHODS: Clinicians requesting cranial CT scans from the emergency department prospectively filled out a form detailing their patients' complaints, possible diagnoses, and the likelihood of finding those diagnoses on CT. The results of the scans were catalogued according to diagnosis and classified as acutely abnormal, chronically abnormal, or normal. RESULTS: Analysis of 536 consecutive patients showed a significant direct correlation between clinical prediction of CT abnormality and scan results. No definite differences in the ability to predict scan results were observed among different physician training levels. Thirty-six patients had acute abnormalities on CT despite a clinical prediction of remote or low likelihood. CONCLUSION: Although clinical predictions of CT abnormality correlate with actual CT results, the correlation is not adequately refined to rely on for selection of patients for emergency cranial CT scans.

Acute Disease↗
PubMed1994

Diagnosis of focal bone lesions using neural networks.

RATIONALE AND OBJECTIVES: Use of a neural network to diagnose focal lesions of bone was evaluated. METHODS: Imaging features of 709 lesions were encoded into a predetermined database. Data were divided into four groups and were analyzed using cross-validation by a two-layer feed-forward neural network. RESULTS: The lesions comprised 43 different pathologic diagnoses. Overall, the network was 85% accurate in distinguishing benign from malignant lesions. With a differential list of five diagnoses, the list was internally consistent regarding benign and malignant lesions 81.9% of the time. The network correctly diagnosed 56% of the lesions by pathologic diagnosis as its first choice. It included the correct diagnosis 71.8% of the time in a differential list of three diagnoses and 87.3% of the time in a differential list of nine diagnoses. CONCLUSION: Although not yet adequate for clinical use, neural network diagnosis of bone lesions is in its infancy and has important implications for the future analysis of focal bone lesions.

Bone Neoplasms↗
PubMed1994

Painful transient tibial edema.

PURPOSE: To report four cases of leg pain resembling transient bone marrow edema (TBME). MATERIALS AND METHODS: Four women aged 51-71 years had lower leg pain that regressed over 3-13 months. All patients underwent physical examination, clinical testing, radiography, scintigraphy, and magnetic resonance (MR) imaging. One patient underwent computed tomography; two underwent biopsy. RESULTS: All patients had tenderness at physical examination, and one had erythema and mild swelling over part of the leg. No laboratory results suggested systemic illness or infection. All had normal radiographs and abnormal bone scans, with increased radiopharmaceutical uptake in the tibial diaphyses. MR imaging showed decreased signal intensity with T1-weighting and increased signal intensity with inversion recovery. There were also signal intensity changes consistent with edema in the surrounding soft tissues. Biopsies showed focal marrow fibrosis and new bone formation with foci of devitalized bone. CONCLUSION: These cases resemble TBME but are unusual in their distribution. Whether they represent a previously undescribed clinical syndrome or a variant of TBME remains to be clarified.

Aged↗