Skeletal Radiographs Research Articles

Digital skeletal radiography . Reduction of absorbed dose by adaptation of exposure factors and image processing

Purpose: The possibility to reduce the absorbed dose to the patient by increase of tube potential while maintaining the same exposure to the image plate and sufficient image quality in skeletal radiography has been investigated. Material and Methods: Image processing parameters were adjusted to account for an increase in tube potential by 20 kV. Revision of image processing parameters was based on measurements with phantoms constructed to simulate the histogram shape recorded for clinical images. Image quality was evaluated both using image quality criteria and visual grading analysis. Energy imparted was calculated from measurement of the kerma-area-product. Results and Conclusion: Energy imparted was reduced by 20–30% using the modified technique with increased kV. All images were considered of accurate quality for diagnosis and the difference in image quality score was marginal. There was, however, a significant shift towards lower grades for the “high kV” technique using visual grading analysis.

Pitfalls in the diagnosis of childhood leukaemia.

Pitfalls in the diagnosis of childhood leukaemia.

Skeletal development of achondroplasia: analysis of genotyped patients.

Achondroplasia is a skeletal dysplasia caused by substitution of arginine for glycine at codon 380 (G380R) mutation of the fibroblast growth factor receptor 3. To date, the developmental course of the phenotype (short stature and skeletal characteristics) has not been clarified in the genotyped population. The relationship between age and clinical data (height, arm span and measurements of skeletal radiographs) were statistically analyzed from 27 achondroplasia patients with the G380R genotype. The height standard deviation score had positive correlation and decreased with age, while span-to-height ratio did not. Among measurements of skeletal radiographs, the pelvic index, which represents the squared pelvis deformity, were correlated and increased with age. However, interpedicular distance of the first and fourth lumbar vertebrae (L1:L4) ratio as an index for the caudally narrowed pattern of the lumbar spinal canal and fibula-to-tibia ratio for the disproportionally long fibulae were not correlated and did not increase with age. In making a clinical diagnosis of achondroplasia in early infancy, it should be noted that short stature and squared pelvis deformity are not prominent.

Extended focal-film distance technique: an analysis of the factors in dose reduction for the AP knee radiograph

Purpose : While an increase in focal film distance (FFD) is an effective method of reducing the entrance skin dose received by a patient, the literature is not agreed on the principal factors involved. Past work has suggested that the reasons for dose reductions may include geometric factors, air attenuation, reciprocity law failure, extra focal radiation, changes in the scatter to primary radiation ratio (s/p) and back-scatter factor variations. This diversity of opinion can lead to confusion when the technique is applied to other areas of skeletal radiography, and hence is investigated in this paper.Method : The effect of increasing FFD from 100cm to 176cm was investigated for a non-Bucky knee radiograph. A 16.2cm thick anthropomorphic knee phantom was radiographed at 60kVp with the mAs varied to give a constant density on the radiograph. Steel ball bearings were taped to the phantom surface to calculate s/p on the resulting radiographs. Dose measurements were made both with and without the phantom present allowing the backscatter factor to be calculated for both varying FFD and collimator settings. Air attenuation measurements were calculated using a computer programme.Results : Results showed that the skin dose reduction was 13.4% at 176cm FFD with 0.8% due to extra focal radiation variations. This compares to 14.8% (theoretically calculated due to geometric considerations alone) with 3.5% calculated to be due to air attenuation. No variations in s/p and backscatter factor were measured.Conclusions : Geometric factors are the main factors in dose reduction with increasing FFD. Caution is urged when extending this technique to include a grid, as grid-focus decentring would be expected to lessen dose reduction.

Positive Findings on Bone Scan in Multiple Myeloma

We report a case of multiple myeloma in which the bone lesions showed high uptake of technetium Tc 99m methylene diphosphonate on a bone scan. A review of the literature comparing the usefulness of conventional skeletal radiography and bone scans in diagnosing the osteolytic lesions of myeloma shows that bone scintigraphy, considered by many to have no role in the detection of osteolytic lesions of myeloma, is in fact more sensitive than radiography in detecting lesions in the ribs, scapula, and spine.

Digital Radiography of the Skeleton Using a Large-Area Detector Based on Amorphous Silicon Technology: Image Quality and Potential for Dose Reduction in Comparison with Screen-Film Radiography

AIM: The purpose of this study was to evaluate a large-area, flat-panel X-ray detector (FD), based on caesium-iodide (CsI) and amorphous silicon (a-Si) with respect to skeletal radiography. Conventional images were compared with digital radiographs using identical and reduced radiation doses.MATERIALS AND METHODS: Thirty consecutive patients were studied prospectively using conventional screen-film radiography (SFR; detector dose 2.5μGy). Digital images were taken from the same patients with detector doses of 2.5, 1.25 and 0.625μGy, respectively. The active-matrix detector had a panel size of 43×43cm, a matrix of 3×3K, and a pixel size of 143μm. All hard copies were presented in a random order to eight independent observers, who rated image quality according to subjective quality criteria. Results were assessed for significance using the Student's t -test (confidence level 95%).RESULTS: A statistically significant preference for digital over conventional images was revealed for all quality criteria, except for over-exposure (detector dose 2.5μGy). Digital images with a 50% dose showed a small, statistically not significant, inferiority compared with SFR. The FD-technique was significantly inferior to SFR at 75% dose reduction regarding bone cortex and trabecula, contrast and overall impression. No statistically significant differences were found with regard to over- and under-exposure and soft tissue presentation.CONCLUSION: Amorphous silicon-based digital radiography yields good image quality. The potential for dose reduction depends on the clinical query.Volk, M. (2000). Clinical Radiology55, 615–621.

Satisfaction of search in osteoradiology.

"Satisfaction of search" describes a situation in which the detection of one radiographic abnormality interferes with that of others. This phenomenon has not been investigated for the interpretation of skeletal radiographs. We determined whether satisfaction of search occurs in the interpretation of conventional radiographs of the musculoskeletal system. Twelve volunteers from radiology (10 residents and two staff members) and 13 volunteers from orthopedic surgery (all residents) were shown in random order 15 cases in which one abnormality was present and 15 cases in which either two or three abnormalities were present. The cases with multiple findings contained a total of 19 abnormalities. All cases were selected from the emergency department. The volunteers received three scores reflecting their ability to detect abnormalities on a single-finding case, at least one abnormality on a multiple-finding case, and additional findings in cases with multiple abnormalities. The scores were compared using the chi-square test with Yates correction. Analysis of variance and Bonferroni adjustment were also performed. Among the cases with single findings, detection rates averaged 11.25; for the 15 multiple-finding cases, the detection rate for one finding averaged 11.72. The difference was not statistically significant. Detection rates for the second and third abnormalities in the multiple-finding cases were significantly lower, averaging 6.12 (p < 0.01). A significant satisfaction of search effect occurred and was operative in the interpretation of radiographs of the musculoskeletal system.

North America

North America

Nutritional aspects of chronic liver disease and liver transplantation in children.

Nutritional aspects of chronic liver disease and liver transplantation in children.

著明な高アルカリフォスファターゼ血症を呈した無症候性多発骨転移の１例

A case of metastatic carcinomatosis of the bone marrow with hyperphosphatasia is reported.Even if patients with marked hyperphosphatasia have no symptom and no abnormal findings of skeletal radiographs, it is possible that their hyperphosphatasia is caused by metastatic carcinomatosis of the bone marrow due to adenocarcinoma.Bone scintigram is useful for the diagnosis of metastatic carcinomatosis of the bone marrow.

Computerized analysis of radiographic bone patterns: effect of imaging conditions on performance.

We are developing computerized methods for characterizing the bone texture pattern from digitized skeletal radiographs. For this method to be useful clinically, it must be able to distinguish between weak and strong bone under the range of exposure conditions potentially encountered in the clinical setting. In this study, we examined the effect of exposure conditions on Fourier-based texture features. Thirty-four femoral specimens from total hip arthroplasties were radiographed multiple times under different exposure conditions. The specimens underwent mechanical strength testing from which load to failure values were obtained. The performance of the texture features were investigated in the task of distinguishing between strong and weak bone as characterized by the load to failure values. The texture features showed no dependence upon focal spot size of the x-ray tube or magnification. The texture features did show a dependence with relative exposure, peak kilovoltage, and amount of scattering material.

Computerized radiographic texture measures for characterizing bone strength: a simulated clinical setup using femoral neck specimens.

We are investigating computerized methods to ultimately characterize bone trabecular pattern from clinical skeletal radiographs. In this paper, we present a "phantom" for potential use in the development and evaluation of computerized methods for characterizing radiographic trabecular patterns and ultimately bone strength. Femoral neck specimens were excised during total hip arthroplasties from subjects exhibiting a range of diseases. To mimic the femoral neck in vivo, a "simulated clinical" setup was implemented in which specimens were exposed under conditions that yielded radiographs similar in appearance to standard pelvis radiographs. Fourier-based and fractal-based texture measures were used in the computer analysis; including RMS variation, first moment of the power spectrum, angular-dependent forms of these measures, and fractal dimension. The texture measures obtained from the "simulated clinical" specimen films correlated modestly with those from direct exposure "verification" films of the specimens (r= 0.59-0.69; p<0.0001). From our study, we conclude that the femoral neck specimen "phantoms" may be useful in the development and evaluation of computerized methods for analyzing bone trabecular patterns from skeletal radiographs. The use of a phantom that simulates the clinical radiographic examination allows for repeat exposures without the concern of excessive radiation exposure to a patient.

Flat panel detectors — closing the (digital) gap in chest and skeletal radiology

In the radiological department today the majority of all X-ray procedures on chest and skeletal radiography is performed with classical film-screen-systems. Using digital luminescence radiography (DLR or CR, which stands for Computed Radiography) as a technique has shown a way to replace this 100-year-old procedure of doing general radiography work by acquiring the X-rays digitally via phosphor screens, but this approach has faced criticism from lots of radiologists world wide and therefore has not been widely accepted except in the intensive care environment. A new technology is now rising based on the use of so called flat panel X-ray (FD) detectors. Semi-conducting material detects the X-rays in digital form directly and creates an instantaneous image for display, distribution and diagnosis. This ability combined with a large field of view and — compared to existing methods — excellent detective quantum efficiency represents a revolutionary step for chest and skeletal radiography and will put basic X-ray-work back into the focus of radiological solutions. This paper will explain the basic technology of flat panel detectors, possible system solutions based on this new technology, aspects of the user interface influencing the system utilization and versatility as well as the possibility to redefine the patient examination process for chest and skeletal radiography. Furthermore the author discusses limitations for the first released systems, upgrades for the installed base and possible scenarios for the future. e.g. fluoroscopy or angiography application.

Early‐infantile galactosialidosis: Prenatal presentation and postnatal follow‐up

Galactosialidosis (GS) is an autosomal recessive condition caused by combined deficiency of the lysosomal enzymes β-galactosidase and α-neuraminidase. The combined deficiency has been found to result from a defect in protective protein/cathepsin A (PPCA), an intralysosomal protein which protects these enzymes from premature proteolytic processing. The most severe form of GS, the early-infantile form, results in early onset of edema, ascites, visceromegaly, and skeletal dysplasia. We report a case of early-infantile GS in a male infant who presented with nonimmune fetal hydrops (NIH), “coarse” facial appearance, massive fluid-filled inguinal hernias, multiple telangiectasia, and diffuse hypopigmentation; he subsequently developed visceromegaly. The diagnosis of GS was confirmed biochemically and the defect in PPCA characterized at the protein level. Examination of fetal peripheral blood smears sampled at 30 weeks gestation demonstrated vacuolation of lymphocytes, suggesting blood film examination may be a useful screening tool for cases of NIH where a metabolic disorder is suspected. Skeletal radiography at birth demonstrated punctate epiphyses of the femora, calcanei, and sacrum. We present a discussion of and differential diagnosis for this radiographic finding. To the best of our knowledge, this is the first case of early-infantile GS presenting with stippled epiphyses. Am. J. Med. Genet. 85:38–47, 1999. © 1999 Wiley-Liss, Inc.

Effect of Calcitriol and Pamidronate in Multiple Myeloma

Addition of bisphosphonates to standard treatment of multiple myeloma (MM) decreases bone pain and skeletal events without influencing bone healing. Calcitriol, besides its established effects on bone remodeling and calcium metabolism, has both immunoregulatory and cell differentiating effects in vitro and in vivo. Moreover, low serum calcitriol has been reported in MM. We tested the effects of supportive treatment with calcitriol and pamidronate on bone disease in two stage-lll-B MM patients with diffuse bone involvement, normal serum calcium, and low serum calcitriol. Complete blood counts, serum calcium, creatinine, quantitative serum and urine immunoglobulins, and biochemical indices of bone turnover, serum calcidiol, calcitriol, parathyroid hormone, skeletal radiographs, and bone mineral density by dual x-ray absorbtiometry were measured every 1–6 months for 16 months in the first patient and 7 months in the second patient. Both patients showed a dramatic improvement of MM activity and in bone disease documented by serial radiographs in the first patient and by increased bone mineral density (approximately 15%) in the second. The reduced serum calcitriol in both patients and the elevated parathyroid hormone observed in the first patient before treatment returned to normal. Supportive treatment with pamidronate does not induce bone healing in MM. Therefore, the results observed with the addition of calcitriol suggest that this hormone may have contributed to the apparent arrest of the progression of MM and caused stimulation of bone healing.

Interpretation of selected accident and emergency radiographic examinations by radiographers: a review of 11000 cases.

Two specially trained radiographers took part in the radiologists' rota for "cold" reporting skeletal radiographs of patients who attended the Accident and Emergency (A&E) Department at times when there was no "hot" reporting service operating, and who were not admitted for treatment or referred to fracture clinics for follow-up. These radiographs had initially been seen by A&E medical staff. At the end of an 18 month period during which the two radiographers reported on 11,322 skeletal examinations, a retrospective search was made to detect interpretive errors. The radiological history of all 11,322 patients was reviewed over a follow-up period of at least 3 months subsequent to the attendance reported by the radiographers. 48% of patients did not re-attend, 42% re-attended for unrelated examinations, and 10% re-attended for repeat examinations of the same anatomical area, or for different procedures (bone scintigraphy or CT) related to the original injury. The second (or subsequent) report was discrepant with that of the first attendance in only 29 cases out of 1103. Of these 29 patients, 13 had occult fractures which were undetectable at first attendance even in retrospect, six had new injuries accounting for the new findings, six had been the subject of false positive calls at an earlier visit, one had a fracture of the hamate missed at first attendance, and in three cases no consensus could be reached as to the cause of the discrepancy, owing to incomplete films or insufficient clinical data. Analysis of the patients' postcodes showed at least 89% were of local origin and only 1% were from outside Yorkshire, suggesting that the review should have identified the great majority of erroneous reports. It is concluded that appropriately trained and supervised radiographers can successfully undertake diagnostic reporting of selected skeletal examinations on A&E patients.

Early-infantile galactosialidosis: Prenatal presentation and postnatal follow-up

Galactosialidosis (GS) is an autosomal recessive condition caused by combined deficiency of the lysosomal enzymes beta-galactosidase and alpha-neuraminidase. The combined deficiency has been found to result from a defect in protective protein/cathepsin A (PPCA), an intralysosomal protein which protects these enzymes from premature proteolytic processing. The most severe form of GS, the early-infantile form, results in early onset of edema, ascites, visceromegaly, and skeletal dysplasia. We report a case of early-infantile GS in a male infant who presented with nonimmune fetal hydrops (NIH), "coarse" facial appearance, massive fluid-filled inguinal hernias, multiple telangiectasia, and diffuse hypopigmentation; he subsequently developed visceromegaly. The diagnosis of GS was confirmed biochemically and the defect in PPCA characterized at the protein level. Examination of fetal peripheral blood smears sampled at 30 weeks gestation demonstrated vacuolation of lymphocytes, suggesting blood film examination may be a useful screening tool for cases of NIH where a metabolic disorder is suspected. Skeletal radiography at birth demonstrated punctate epiphyses of the femora, calcanei, and sacrum. We present a discussion of and differential diagnosis for this radiographic finding. To the best of our knowledge, this is the first case of early-infantile GS presenting with stippled epiphyses.

Compound heterozygosity for the achondroplasia-hypochondroplasia FGFR3 mutations: Prenatal diagnosis and postnatal outcome

We report on a male newborn infant, a compound carrier of heterozygous mutations in the FGFR3 gene causing achondroplasia and hypochondroplasia. The mother has achondroplasia and carries the common G1138 (G380R) mutation in the FGFR3 gene; the father has hypochondroplasia due to the C1620A (N540K) mutation in the same gene. The fetus was found to carry both mutations diagnosed prenatally by amniocentesis at 17.6 weeks of gestation, following maternal serum screening which showed an increased risk for Down syndrome (1:337). Detailed fetal ultrasound studies showed a large head, short limbs, and a small chest at 22 weeks of gestation. The changes were more severe than those of either achondroplasia or hypochondroplasia. The patient was born by cesarean section at 38 weeks of gestation and had rhizomelic shortness of the upper and lower limbs with excess skin folds, large head, enlarged fontanelles, frontal bossing, lumbar gibbus, trident position of the fingers, and a narrow chest with a horizontal line of demarcation at the narrowest area of the chest. Skeletal radiographs showed shortness of the long bones and flare of metaphyses. He had respiratory difficulties and was treated with nasal prongs. Seizures developed on day 2 of life and recurred on day 9 and responded to treatment with phenobarbital. Brain computed tomographic scan showed possible grey matter heterotopia, partial agenesis of the corpus callosum, and cortical dysplasia. To our knowledge, there are only two previously published cases of compound heterozygous achondroplasia-hypochondroplasia patients. The diagnosis was confirmed by DNA mutation analysis of the FGFR3 gene in both cases.

Variation between experienced observers in the interpretation of accident and emergency radiographs.

Skill mix and role extension initiatives have highlighted the difficulty of establishing quality standards for the accuracy of plain film reporting. An acceptable performance might be one which is indistinguishable from that of a group of experienced consultant radiologists. In order to assess the feasibility of setting such a standard, the variation between experienced observers must first be established. This study examines the variation found between three observers with the three major types of plain film examination. 402 plain film examinations (205 skeletal, 100 chest and 97 abdominal) performed on accident and emergency patients were reported retrospectively and independently by three experienced radiologists. The clinical data supplied on the request cards were available to the readers. Each examination was categorized by each reader as being normal, as showing significant abnormality relevant to the current clinical problem, or as showing insignificant or irrelevant abnormality. Concordance between all three readers was found in 51%, 61% and 74% of abdominal, chest and skeletal radiographs, respectively. Weighted kappa values confirmed that the level of agreement between pairs of observers was higher with skeletal radiographs (kappa w = 0.76-0.77) than with chest (kappa w = 0.63-0.68), or abdominal (kappa w = 0.50-0.78) examinations. However, the frequency of major disagreements (at least one reader reporting "normal" and one reporting "relevant abnormality") was similar for abdominal (11%), chest (12%) and skeletal (10%) radiographs. When the reports were reclassified into only two groups--either significantly abnormal or not--pairs of observers disagreed on 9-10% of skeletal, 11-19% of chest and 8-18% of abdominal cases. The average incidence of errors per observer was estimated to be in the range 3-6%. The magnitude of interobserver variation in plain film reporting is considerable, and must be taken into account when designing assessment techniques and setting quality standards for this activity.

Monitoring Therapeutic Response in Skeletal Metastases Using Dual-Energy X-Ray Absorptiometry: A Prospective Feasibility Study in Breast Cancer Patients

Response to systemic therapy in breast cancer patients with lytic skeletal metastases manifests as a shift from increased bone resorption to new bone formation. We hypothesized that dual-energy x-ray absorptiometry (DXA) could be used to pro-spectively quantitate changes in bone mineral density (BMD) in metastatic skeletal lesions in breast cancer patients receiving systemic therapy. Nine metastatic breast cancer patients with one or more assessable lytic skeletal metastases receiving systemic therapy were prospectively evaluated with DXA, skeletal radiographs, computed tomography (CT), and radionuclide bone scans at baseline (t = 0 months, 2 months, and 6 months). The median (range) percentage change in BMD in skeletal lesions among patients responding to systemic therapy was 10.7% (0.1–21.85), 5.0% (-1.3–234, and 16.7% (-2.0–50.8) at 0–2, 2–6, and 0–6 months, respectively. Changes in BMD between 0–2, and 0–6 months were significant (Wilcoxin signed rank test; p = 0.013 and p = 0.017, respectively). The percentage change in BMD skeletal lesions between 0–2 and 2–6 months correlated with the changes imaged on skeletal x-rays (Spearman rank order correlation coeficient (Rs,] = 0.511, p = 0.011) and CTs (Rs, = 0.416, p = 0.046) but less so with bone scans (Rs, = 0.293, p = 0.189). It is technically feasible to use DXA to prospectively monitor changes in lytic skeletal metastases in breast cancer patients receiving systemic therapy. The BMD of skeletal metastases increases in patients responding to treatment and was significantly correlated with the changes imaged on skeletal x- rays and CTs. Additional studies of DXA to evaluate response in skeletal metastasis are warranted.