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W R Reinus

Publications and source records attributed to W R Reinus.

At least 19 recordsLinked to original sources
PubMed2000

A proposed scheduling model to improve use of computed tomography facilities.

A nonpreemptive queuing system based upon operations management theory is used to evaluate expected steady state wait periods for traditional and distributed CT scheduling models. Both models are constructed using two classes of patient service--emergent and nonemergent. The former model uses only one point of service per scanner while the latter employs multiple points of service in order to accomplish all of the functions necessary to complete a CT scan. Sample data are drawn from a tertiary care hospital-based system using a traditional service model. Comparison of a traditional and distributed service system, each with emergent and nonemergent service classes, shows that breaking as many activities as possible out of the scanner should provide substantial improvements in cost efficiency and service for patients having CT scans. Nonemergent patients may experience as much as an 89% reduction in steady-state wait times while emergent patients may experience as much as a 59% reduction in wait times. The cost efficiencies recognized either through increased scanner utilization or reduced scanner needs, even with only modest improvements, should more than offset any additional personnel needed to implement a distributed model. Proper implementation of a distributed scheduling model for CT scanning can provide substantial cost efficiencies and improvements in service for both nonemergent and emergent CT scans.

Appointments and Schedules↗
PubMed2000

Expansile skeletal hyperphosphatasia: a new familial metabolic bone disease.

We describe a new familial metabolic bone disease characterized by expanding hyperostotic long bones, early onset deafness, premature tooth loss, and episodic hypercalcemia. The condition affects a mother and daughter studied at the age of 36 years and 11 years, respectively. Both individuals lost all hearing in early childhood and suffered premature shedding of teeth. Skeletal pains began just before puberty. Swelling and aching of most middle phalanges in the hands is an especially troublesome manifestation. The mother also had episodes of symptomatic hypercalcemia first documented in late childhood and subsequently during intercurrent illness and postpartum lactation. Radiographs show hyperostosis and/or osteosclerosis predominantly in the skull and appendicular skeleton. Long bones also are expanded considerably, especially the middle phalanges in the fingers. The mother's skeletal abnormalities are more severe. Biochemical parameters of bone turnover, including serum alkaline phosphatase (ALP) activity, are elevated substantially. In the proposita, dynamic histomorphometry of nondecalcified sections of iliac crest revealed rapid skeletal remodeling. In the mother, who had been treated with bisphosphonates, electron microscopy (EM) showed disorganized collagen bundles as well as necrotic and apoptotic bone cells but no osteocytic osteolysis. Measles virus gene transcripts were not detected in peripheral blood monocytes. Karyotyping was normal, 46,XX. Hyperphosphatasia with bone disease previously has been reported as either a sporadic or autosomal recessive condition. Expansile skeletal hyperphosphatasia (ESH) is probably inherited as an autosomal dominant trait with a high degree of penetrance.

Adult↗
PubMed2000

"Café-au-lait spots" caused by vitiligo in McCune-Albright syndrome.

Café-au-lait spots, fibrous dysplasia of bone, and endocrine gland hyperactivity are the principal features of McCune-Albright syndrome (MAS). Café-au-lait spots appear at, or soon after, birth. We illustrate "café-au-lait spots" acquired during middle age in a patient with MAS that are an illusion caused by vitiligo. This 64-year-old woman is the oldest patient reported with this disorder.

Cafe-au-Lait Spots↗
PubMed1999

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

RATIONALE AND OBJECTIVES: The authors determine the features that distinguish the radiographic appearance of unicameral bone cysts (UBC) from other solitary lesions of bone and to develop an ordered differential of similar-appearing lesions. MATERIALS AND METHODS: Seven hundred nine cases of solitary bone lesions, including 40 UBCs, were analyzed according to demographic, anatomic, and plain radiographic features. Vector analysis of both classic and new groups of features was performed to determine the sensitivity and specificity of radiographs for UBC and an ordered differential based on radiographic features. RESULTS: The features of the UBCs in this study compared favorably with those in the literature. The male:female ratio was 3.3:1, with an average age of 15 +/- 13 years. Age ranges and lesion diameters were similar for both sexes. Thirty-three of the 40 (83%) UBCs were in long bones, and seven were in the pelvis or calcaneus. All 40 UBCs were geographic, medullary, and lytic. None had an associated soft-tissue mass. Fifty-five percent had pathologic fractures, and 10% had fallen fragment signs. Ninety-eight percent had no cortical break, and 88% had well-defined margins. CONCLUSION: Classic descriptions of UBCs can be refined to improve sensitivity without sacrificing specificity. The best vector in this study had a sensitivity of 80% and a specificity of 93% and included these radiographic features: metaphyseal, diaphyseal, or flat bone location, geographic, lytic, medullary-based, no matrix, no satellite lesions, no subarticular extension, no soft-tissue mass, no cortical break, and central location in long bones. An ordered differential diagnosis, starting with the most likely lesion, includes enchondroma, aneurysmal bone cyst, fibrous dysplasia, nonossifying fibroma, Brodie abscess, and chondrosarcoma.

Adolescent↗
PubMed1998

Differing lumbar vertebral mineralization rates in ambulatory pediatric patients with osteogenesis imperfecta.

The purpose of this study was to evaluate serial changes in bone mineral density (BMD) of the lumbar spine in individual children and adolescents with untreated osteogenesis imperfecta (OI) using dual X-ray absorptiometry (DXA). Twenty-seven pediatric patients with OI who had no historical or radiographic evidence of lumbar fracture, required no assistive device for mobility, and were taking no medications known to affect skeletal mineralization during the study period comprised the investigational group. Absolute BMD and age- and gender-matched BMD (Z-scores) were assessed relative to standard parameters of growth (height, weight, age, height adjusted for age and gender and body surface area) and severity of disease (lifetime fracture rate). The spinal mineralization rate (SMR) between examinations for 15 patients with more than one measurement (n = 20 intervals) was expressed as the magnitude of the change in BMD Z-score per year. Both BMD and BMD Z-score were closely correlated with height, height Z-score, weight and body surface area and were inversely related to fracture rate (P < 0.001 for all comparisons). BMD was also highly correlated with patient age (P < 0.001). Stepwise regression analysis showed that together height Z-score and lifetime fracture rate improved the prediction of BMD Z-score (r = 0. 71; P < 0.001). SMRs ranged from -0.5 to 3.5. The average change in SMR between sequential measurements was 168% for the five children who had more than two DXA examinations. Linear regression showed a significant negative correlation between SMR and height Z-score (r = -0.79, P < 0.001). We conclude that vertebral body size is a critical determinant of BMD and BMD Z-score in OI because DXA results are expressed per unit area, not per unit volume. Pediatric patients with OI mineralize their lumbar vertebrae at rates similar to healthy children but tend to lag behind in overall mineralization. The rate of mineralization at any age appears to be related to the patient's height (adjusted for age- and gender-matched controls) and inversely related to the patient's lifetime rate of fractures. Our data suggest that vertebral mineralization in children with OI is related primarily to rapid increases in vertebral volume and only secondarily to increases in vertebral mineral density.

Adolescent↗
PubMed1998

Fractures of the greater tuberosity presenting as rotator cuff abnormality: magnetic resonance demonstration.

BACKGROUND: To show that magnetic resonance imaging (MRI) can be useful to diagnose radiographically invisible greater tuberosity fractures in patients with clinical presentations suspicious for rotator cuff injury. METHODS: Six patients with subtle greater tuberosity fractures who were sent for MRI because of possible rotator cuff tear are reviewed (age range, 27-51 years; mean, 40.5 +/- 8.4 years). Five of the patients recount direct trauma to their shoulders, whereas one noticed shoulder pain after a fall in which she fractured her ankle. RESULTS: MRI showed an area of edema confined to the greater tuberosity with linear low signal extending through the tuberosity consistent with a fracture in all cases. Although five patients had a complete set of shoulder radiographs before MRI, these were interpreted as normal in all cases. Full-thickness rotator cuff tears were not present in any of the cases. All of the patients were treated conservatively with good results. CONCLUSIONS: MRI can prevent unnecessary arthroscopy in patients clinically suspected of rotator cuff damage by showing subtle fractures of the greater tuberosity not visible on radiographs.

Accidental Falls↗
PubMed1998

Hepatitis C-associated osteosclerosis: late onset after blood transfusion in an elderly woman.

A 69-yr-old woman with hepatitis C virus (HCV) infection from blood transfusion 14 yr earlier was evaluated in 1997 for increasing appendicular skeletal pain. Diffusely elevated radioisotope uptake on bone scanning had appeared during the past 15 months. Radiographs spanning 1978-1997 showed remarkable restoration of bone mass and a skeleton like that of a young woman. Bone mineral densities of the femoral neck and lumbar spine were above the mean peak bone mass of young women (T scores, +1.8 and +1.3, respectively) and 160% and 147% of mean values for age-matched female controls (Z-score, +3.7 and +3.6, respectively). Biochemical markers of skeletal remodeling were substantially increased. Bone marrow biopsy showed normal lamellar bone. Serum alkaline phosphatase activity assays suggested that accelerated skeletal turnover began 6-12 months before symptoms. HC-associated osteosclerosis has been reported in nine individuals 27-73 yr of age, most with a history of i.v. drug abuse. Our patient demonstrates that parenteral exposure to blood rather than illicit drugs is the feature common to all affected subjects. Furthermore, we document that there can be a long latency between HCV infection and the development of skeletal abnormalities. We also find that bone mass can be restored by this disorder in a postmenopausal woman. Routine radiographs, however, may not show overt osteosclerosis in the elderly. The precise pathogenesis of this disorder is unknown. Understanding and control of the mechanism of HC-associated osteosclerosis could potentially lead to correction of low bone mass from osteoporosis with good quality skeletal tissue.

Adult↗
PubMed1998

Use of lumbosacral spine radiographs in a level II emergency department.

OBJECTIVE: We studied indications for lumbosacral spine radiographs in an emergency department setting. SUBJECTS AND METHODS: Clinicians completed a lumbosacral spine request form before obtaining lumbosacral radiographs on 482 patients who were examined in a level II emergency department. The clinicians detailed the indications for the examination, their suspected clinical diagnoses, and the expected effect of the lumbosacral spine study on management. In addition, the duration of the patients' symptoms was recorded as well as their age and sex. These data were compared with the actual radiographic findings as interpreted by board-certified musculoskeletal radiologists. RESULTS: Major indications for lumbosacral radiographs were lower back pain (92%) and trauma (36%). Patient expectation and medicolegal concerns, related either to insurance documentation or to physician litigation, were cited in 42% of cases. A neurologic deficit was present in 88% of patients, and a history of neoplasm was elicited in 4%. Strain (56%) and fracture (20%) were the most commonly suspected clinical diagnoses. Radiographs showed either normal findings or spondylosis in 86% of cases. Fractures, of which 10 were definitely acute, were identified in 55 patients. No fracture required decompression. Neoplastic involvement was found in seven patients, all of whom had histories of osseous metastases. Neurologic deficit, present in 37 patients, did not correlate with abnormalities seen on lumbosacral radiographs. CONCLUSION: As with studies of lumbosacral spine radiographs obtained in outpatient settings, our data from a level II emergency department support the use of lumbosacral spine radiographs for patients with a history of trauma, even if relatively minor, in elderly patients and in patients with lower back pain who have a history of neoplasm. Lumbosacral radiographs obtained for an isolated complaint of lower back pain generally provide no clinically useful information. Similarly, lumbosacral radiographs obtained for patients with isolated neurologic abnormalities are unrevealing. Such patients are better examined (although not necessarily at the time of emergency department evaluation) with techniques such as MR imaging that show soft-tissue lesions.

Aged↗
PubMed1998

The linear intravertebral vacuum: a sign of benign vertebral collapse.

OBJECTIVE: We describe 11 patients with radiographically visible linear intravertebral vacuums to increase awareness of this benign finding that is diagnostic of ischemic necrosis of the vertebral body (Kümmell's disease). MATERIALS AND METHODS: We retrospectively reviewed the radiologic and clinical histories of 11 patients seen at our institution between 1991 and 1997 in whom the linear intravertebral vacuum phenomenon had been diagnosed. Imaging included plain radiographs in all patients, CT scans in three, bone scintigrams in three, and MR images in three. RESULTS: Twelve linear intravertebral vacuums associated with vertebral compression deformities were visible in 11 patients from T8 to L2, four at T12, and four at L1. Of the 12 linear intravertebral vacuums, seven (58%) were seen by the initial interpreting radiologist. The mean age of these patients was 76.6 years. The female:male ratio was 10:1. During the period of analysis, two patients were known to have malignancy, one with metastasis to the spine but not to the affected vertebral body. One patient, who underwent equivocal MR imaging for malignancy, later underwent bone biopsy, which showed no neoplasm within the collapsed vertebra. Of the remaining nine patients, one was undergoing chronic corticosteroid therapy and another had a history of radiation therapy to the spine. Seven of the 11 patients had histories of falling, prompting radiographs of the spine. All 11 patients were radiographically osteopenic. Ultimately, none of the patients had clinical evidence of neoplasm or infection involving the affected vertebral body. CONCLUSION: Recognition of the near-certain benign significance of a linear intravertebral gas collection revealed by radiography may prevent unnecessary imaging or biopsy in a patient with a suggestive vertebral compression deformity.

Aged↗
PubMed1997

Quantitation of T2' anisotropic effects on magnetic resonance bone mineral density measurement.

In this paper, the authors quantitate the anisotropy of susceptibility effects in an uniaxial trabecular bone model and show its relevance to clinical MR bone mineral density measurements. A physical model is described that quantitates the anisotropic MR behavior of uniaxial trabecular bone. To test the model; a phantom of parallel polyethylene filaments was scanned every 15 degrees between 0 degrees and 90 degrees with respect to the system's main magnetic field (B0). The distal radial metaphysis of a healthy female volunteer was scanned in orthogonal projections. The signal from each phantom image and each radial image was separated in a pixel-wise fashion into R2 and R2' maps. As predicted, R2' relaxation showed anisotropic behavior and changed according to sin2 (theta), confirming that columnar structures parallel with B0 will cause no MR susceptibility effects. Scans of the distal radius showed that R2' relaxation was twice as great with the forearm perpendicular to B0 as when it was parallel to it, demonstrating different contributions from struts and columns. For both phantom and radial bone scans, R2 relaxation was isotropic and did not change with object orientation.

Adult↗
PubMed1997

Prescreening entire mammograms for masses with artificial neural networks: preliminary results.

RATIONALE AND OBJECTIVES: The authors evaluated the feasibility of combining wavelet transform and artificial neural network (ANN) technologies to prescreen mammograms for masses. METHODS AND MATERIALS: Fifty-five mammograms (29 with masses and 26 without) were digitized to 100-mm resolution and processed by using wavelet transformation. These wavelets were subjected to a linear output sequential recursive auto-associative memory ANN and cluster analysis with feature vector formation. These vectors were used in two separate experiments-one with 13 cases and another with seven cases held out in a test set-to train feed-forward ANNs to detect the mammograms with a mass. The experiments were repeated with rerandomization of the data, four and six times, respectively. RESULTS: There was a statistically significant correlation (P < .01) between the network's prediction of a mass and the presence of a mass. With majority voting, the feed-forward ANNs detected masses with 79% sensitivity and 50% specificity. CONCLUSION: Although preliminary, the combination of wavelet transform and ANN is promising and may provide a viable method to prescreen mammograms for masses with high sensitivity and reasonable specificity.

Breast Neoplasms↗
PubMed1997

Modification of the Van Nes rotationplasty: report of a case.

Rotationplasty is a reconstructive option that provides a highly functional limb after tumor resection about the knee in the skeletally immature patient. However, in the very young child with large intramedullary extension of the tumor, leg length may not be possible to maintain. Described is a modification of the Van Nes rotationplasty that preserves the proximal tibial physis, allowing maximization of future growth.

Ankle Joint↗
PubMed1997

Quantitative analysis of the plain radiographic appearance of Brodie's abscess.

RATIONALE AND OBJECTIVES: The authors quantitate the radiographic features that distinguish the plain radiographic appearance of Brodie's abscess (BA) from other solitary lesions of bone. METHODS: Plain radiographs of 709 solitary bone lesions were reviewed, including 21 BAs. These were analyzed according to demographic, gross anatomic, and structural features. Vector analysis of groups of features was performed to determine those that are most sensitive and specific for the radiographic appearance of BA relative to other lesions of bone. RESULTS: Brodie's abscesses, in our series, are most commonly medullary-based (86%) lytic lesions (100%), with a geographic pattern of destruction (100%), well-defined edges (90%), marginal sclerosis (86%), and no bone enlargement (95%). In general, they have no periosteal reaction (71%), cortical break (95%), or visible matrix (90%). They typically are localized to the diaphysis or metaphysis (86%) of tubular bones, particularly in the lower extremity (63%). By vector analysis, the radiographic and demographic description of BA that provided the greatest sensitivity (67%-76%) while maintaining high prevalence (20%-21%) included a well-defined lytic lesion with a geographic pattern of destruction, and no bone enlargement or matrix or cortical break arising in patients younger than 40 years old. Although BAs commonly are small lesions with maximum diameters < 50 mm, size criteria did not greatly affect the sensitivity or specificity for detection of BA in our database. The differential diagnosis generated by vector analysis includes osteoid osteoma, nonossifying fibroma, giant cell tumor, eosinophilic granuloma chondroblastoma, and fibrous dysplasia, as the major lesions. CONCLUSIONS: Although BA can present with a variety of radiographic features, a relatively specific set of radiographic characteristics can be defined to assist in plain-film diagnosis and to help refine the differential diagnosis of similar-appearing lesions.

Abscess↗
PubMed1997

Quantitative analysis of the plain radiographic appearance of Ewing's sarcoma of bone.

RATIONALE AND OBJECTIVES: The authors quantitate the radiographic features that distinguish the plain radiographic appearance of Ewing's sarcoma (ES) from other solitary lesions of bone. METHODS: A total of 709 cases of focal bone lesions, including 44 ES, 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 ES in contrast with other lesions in the database. RESULTS: In our sample, Ewing's sarcoma is most consistently a medullary-based (91%) lytic (89%) lesion with at least a partially permeative appearance (82%), poorly defined edges (82%), no margination (91%), and a soft-tissue mass (61%). When these lesions occur in long bones, they most commonly are found in the diaphysis (75%) and are proximal more often than distal. Vector analysis suggests that any primary bone lesion without radiographically visible matrix and with either a soft-tissue mass, an appearance of permeative destruction alone or in combination with other patterns of bone destruction is suspect for the diagnosis. This small subset of common features appears to have a high sensitivity (89%) and prevalence (47%) of ES among the lesions meeting these criteria. Limiting the age of the patients to progressively younger age groups increases the specificity but lowers sensitivity. The vector analysis-generated differential diagnoses includes osteosarcoma, giant-cell tumor, lymphoma, and chondrosarcoma. CONCLUSIONS: A relatively specific set of radiographic features can be defined, which will assist in the radiographic diagnosis of ES and improve upon current textbook descriptions.

Adolescent↗
PubMed1997

Paget bone disease involving young adults in 3 generations of a Korean family.

Although the etiology of Paget bone disease (PBD) is unknown, increasing evidence implicates a "slow virus" infection of the skeleton, perhaps in genetically predisposed individuals. PBD is rare in Asia. We describe a Korean family with PBD. The propositus noticed bowed limbs at approximately 25 years of age. Radiologic studies made when he was 55 years old revealed essentially panostotic PBD. Serum alkaline phosphatase (ALP) activity and osteocalcin (OC) levels were markedly elevated. An iliac crest specimen showed classic histopathologic changes of PBD. Additionally, palpable swellings were first observed at age 45 years at his occiput, pubic ramus, ileum, and facial bones. They contained numerous multinucleated cells and were originally diagnosed as giant cell tumors. However, we found that, like osteoclasts, these cells expressed considerable tartrate-resistant acid phosphatase activity. These "extraskeletal osteoclastomas" resolved rapidly with dexamethasone treatment. Two daughters, 20- and 24-years-of-age, were discovered by study of his 5 children to have elevated serum ALP activity and OC levels and widespread PBD. Both women, however, are without palpable masses and are asymptomatic. The propositus' father, who died at age 55 years, had similar skeletal deformities beginning at age 20 years, but was not examined. Leukocytopenia was found in the 3 living family members with PBD. There was no evidence for linkage of the PBD to HLA loci. The condition appears to be transmitted as an autosomal dominant trait and is manifest in young adult life. Multicentric extraskeletal osteoclastomas with remarkable sensitivity to dexamethasone treatment appear to be another unusual feature of this family's disorder. In this family, the stimulus for PBD is so great that the PBD is apparent at an early age, affects essentially the entire skeleton, and leads to the formation or extension of osteoclast-like cells into nonosseous tissues (extraskeletal osteoclastomas). This 3-generation kindred in Korea, where PBD is rare, shows a strong clustering of PBD compatible with autosomal dominant inheritance. Leukocytopenia appears to distinguish affected family members, but any role for this abnormality in the pathogenesis of PBD is unclear. Our findings support a heritable diathesis for PBD, perhaps mediated by an immune deficiency.

Adult↗
PubMed1996

Juvenile Paget disease: life-long features of a mildly affected young woman.

Unusually mild Juvenile Paget Disease (JPD) was extensively investigated in a mentally retarded 21-year-old white woman. Progressive bowing deformitity of her lower limbs began at age 1 1/2 years. Nontraumatic fractures of both femora and both tibias occurred between ages 9 and 14 years. During adulthood, cortical thickening, osteosclerosis, and bowing affected these bones. Serum alkaline phosphatase (ALP) activity was persistently elevated. We found her serum osteocalcin and urinary hydroxyproline and pyridinoline/deoxypyridinoline to also be increased. The iliac crest histology, at ages 14 and 21 years, showed wide cortices and enhanced skeletal remodeling yet the bone was exclusively lamellar. Features of classic Paget Bone Disease (PBD)--such as hypermultinucleated osteoclasts, peritrabecular fibrosis, and mosaic or woven bone--were absent. Electron microscopy revealed no cytoplasmic or nuclear inclusions. Her dermal fibroblasts in culture synthesized unremarkable levels of ALP with proper membrane topography and lipid anchoring; ALP released into the medium also appeared normal. Six months of synthetic human calcitonin therapy daily appeared to reduce here lower limb pain and warmth, but the radiographs, biochemical parameters of skeletal turnover, and bone scintigraphy were unaltered. Lamellar bone has been reported in JPD but accompanied by excessive amounts of woven bone. Our patient reveals that lamellar bone without features of PBD can characterize the skeletal histopathology of the especially rare case of mild JPD.

Adult↗