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PubMedDate not supplied

Joint use of clinical parameters, biological markers and CAGE questionnaire for the identification of heavy drinkers in a large population-based sample.

AIMS: Alcohol consumption in France is one of the highest in the world. Factors associated with excessive alcohol drinking are numerous. However, taken separately, none of the existing clinical or biological markers of excessive alcohol intake enables an adequate identification of heavy drinkers. The aim of this cross-sectional survey was to identify socio-demographic, clinical and biological factors associated with excessive alcohol drinking, to develop a model and to assess its reliability, thus enabling the detection of heavy drinkers. METHODS: Subjects were 1619 men and 1559 women, aged 35-64 years, living in three French areas (Lille, Strasbourg and Toulouse) and randomly selected from polling lists. Socio-demographic status, lifestyle, reported alcohol intake and answers to the CAGE questionnaire (alcohol dependence) were obtained by questionnaire. A blood sample was taken for quantification of biological parameters. Men who drank 60 g of ethanol a day (g/day) or above and women who drank 30 g/day or above were classified as heavy drinkers. The reference class (RC) gathered non-drinkers and moderate drinkers together. The sample was divided into two sub-samples: the first was used to estimate the parameters of a logistic regression model (heavy drinkers vs others), and the second to assess the accuracy of this model for the identification of heavy drinkers, using receiver operating characteristic (ROC) curves. A specific analysis was performed for each gender. RESULTS: Fourteen per cent of men and 40.8% of women were non-drinkers. Nine per cent of women and 14.4% of men were heavy drinkers. Wine was the most consumed alcoholic beverage. In the univariate analyses, differences were observed between the two groups of alcohol consumers for most of the socio-demographic, clinical and biological variables considered. In the multivariate analyses, low educational level, smoking, apoprotein B, high density lipoprotein cholesterol, mean corpuscular volume (MCV), gamma-glutamyl-transferase (GGT) and the CAGE score for men, and living area, age, MCV, GGT and the CAGE score for women remained independently and significantly associated with heavy drinking. In the validation sub-sample, these models combining different types of markers enabled a good discrimination between heavy drinkers and the RC, with an area under the ROC curve of 82% for men and of 79% for women. CONCLUSIONS: In this study, socio-demographic, clinical and biological factors and the CAGE score were independently related to excessive alcohol drinking and their joint utilization in a screening model enabled a good recognition of heavy drinkers.

Adult↗

PubMed2006

Magnetic resonance imaging quantification of hand synovitis in patients with rheumatoid arthritis treated with adalimumab.

OBJECTIVE: To investigate the clinical response and to evaluate by magnetic resonance imaging (MRI) the inflammatory tissue changes in patients with refractory rheumatoid arthritis (RA) treated with adalimumab. METHODS: Thirteen patients with refractory RA who were treated with adalimumab (40 mg every 2 weeks subcutaneously) were examined with MRI of the dominant affected wrist and hand before treatment and one year after therapy. The volume of the enhanced inflammatory tissue (VEIT) was evaluated in fat-suppressed contrast-enhanced T1-weighted MRI images using the Analyse 4.0 software. Disease activity was evaluated using the Disease Activity Score 28-joint (DAS-28). Clinical improvement was evaluated according to the American College of Rheumatology 20% response criteria (ACR20%). RESULTS: We studied 12 women and one man, with mean age 52.0 +/- 10.9 years and mean disease duration 13.0 +/- 8.5 years. Eight patients had positive IgM rheumatoid factor. One year after treatment, 11 (84.6%) patients showed a decrease of the VEIT. Moreover the values of C-reactive protein (CRP; 4.3 +/- 6.6 mg/l), the erythrocyte sedimentation rate (ESR; 26.3 +/- 19.5 mm/h), the DAS-28 (3.5 +/- 1.1), and the VEIT (21.6 +/- 10.7 cm3) after treatment were significantly lower compared to the corresponding values before treatment (CRP 41.6 +/- 39.2), (ESR 54.3 +/- 28.6) (DAS-28 5.8 +/- 0.8), and (VEIT 36.9 +/- 16.8) (p < 0.01). All but 3 (76.9%) patients with RA achieved the ACR20% response, while 7 (53.8%) and 5 (38.5%) patients achieved ACR50% and ACR70% response, respectively. A positive correlation between VEIT, swollen joint count, and ESR was found before treatment (r = 0.59, r = 0.64, respectively; p < 0.05). CONCLUSION: In patients with refractory RA, treatment with adalimumab resulted in improvement of clinical, laboratory, and MRI findings. MRI assessment of the VEIT may represent an additional tool for investigation of joint disease activity and responsiveness to treatment.

Adalimumab↗

PubMed1986

Therapeutic effects on cartilage metabolism in arthritis as measured by release of proteoglycan structures into the synovial fluid.

Proteoglycans are molecules that are degraded and released from the articular cartilage into the synovial fluid early in an arthritic process. Such released proteoglycans were quantified by an enzyme linked immunosorbent assay (ELISA). The proteoglycan content in synovial fluid from patients with various knee joint arthritides was constant in two samples withdrawn five days apart. To determine if therapeutic measures were paralleled by effects directly on the articular cartilage the patients were treated with local injections of glucocorticoids. In all patients the glucocorticoids induced a reduction of the proteoglycan content in the synovial fluid, reflecting their effects on the cartilage. In two patients with spontaneous remission of their arthritis a reduction in the proteoglycan content in the synovial fluid was also noted. The quantification of proteoglycans in synovial fluid appears to have potential as a useful tool for monitoring the effects of therapy on cartilage metabolism.

Adult↗

PubMed2005

Magnetic resonance imaging quantification of hand synovitis in patients with rheumatoid arthritis treated with infliximab.

AIM: To investigate the clinical response and to evaluate by magnetic resonance imaging the inflammatory tissue changes in refractory rheumatoid arthritis patients treated with infliximab. METHODS: Sixteen refractory rheumatoid arthritis patients who were treated with intravenous infliximab (3 mg/kg) at weeks 0, 2, 6 and every 8 weeks thereafter were examined with magnetic resonance imaging of the dominant affected wrist and hand before treatment and 1 year after therapy. The volume of the enhancing inflammatory tissue was evaluated in fat suppressed contrast enhanced T1-weighted images by using the Analyse 4.0 software. Disease activity was evaluated by assessing the disease activity score for 28 joint indices. The clinical improvement was evaluated according to the American College of Rheumatology 20% response criteria. RESULTS: There were 13 females and 3 males with mean age 49.5 (17.0) years and mean disease duration 10.5 (8.0) years. Ten patients had positive IgM rheumatoid factor. One year after treatment, a significant reduction of the erythrocyte sedimentation rate, the C-reactive protein, the disease activity score for 28 joint indices and the volume of the enhancing inflammatory tissue was observed. All but two of the rheumatoid arthritis patients achieved the American College of Rheumatology 20% response criteria, while 9 (56.25%) and 5 (31.25%) patients achieved the 50% and 70% American College of Rheumatology response criteria, respectively. A positive correlation among the volume of the enhancing inflammatory tissue, swollen joint count, tender joint count, as well as disease activity score for 28 joint indices (r=0.66, r=0.79, r=0.57 respectively) was found before treatment. CONCLUSIONS: In refractory rheumatoid arthritis patients, the addition of infliximab therapy may result in clinical, laboratory and magnetic resonance imaging improvement. Magnetic resonance imaging assessment of the volume of the enhancing inflammatory tissue may represent an additional tool for the investigation of joint disease activity and responsiveness to treatment.

Adult↗

PubMed1991

Some new trends of biomechanical studies in traumatology and orthopedics.

This article presents four recent areas of research in biomechanics with clinical application. The first area describes quantification of the functional condition of the lower extremity using biomechanical parameters based on theoretical assumptions for a new mathematical model of walking. The second area describes the mechanism of spinal compression fractures from dorsal impact trauma. Preliminary data are derived from anatomic specimen studies. The third area is a description and justification of a new endoprosthetic design, including experimental observations on canine species, for total knee arthroplasties with a unique biomechanical design using a synthetic ribbon for creation of a "rolling joint." The fourth area of investigation deals with the normal and pathologic distribution of pressure on the plantar surface of the foot using an electronic measuring system, along with statistical indices; this system may be able to diagnose various foot deformities by automated methods.

Animals↗

PubMed2005

A scanning electron microscopy-based approach to quantify resorption lacunae applied to the trabecular bone of the femoral head.

Resorption lacunae (RL) are discussed as stressors that can increase the risk of mechanical failure in a trabecular network. Quantification of RL has previously been described through the parameter eroded surface/bone surface (ES/BS) as established by light microscopy (LM) analysis, but the results have been inconsistent and contradictory. Using scanning electron microscopy (SEM), a new study design for quantitative evaluation is introduced. To test its applicability a pilot study was executed with trabecular bone dissected from a femoral head of 28 autopsy subjects (14 female and 14 male). A 2.4 x 2.8 x 1.0 mm sample was excised 1.5 cm below the joint surface of each specimen in coronal medial slices of the femoral head and examined. A virtual grid with 1050 squares superimposed over the generated SEM image allowed determination of the ratio of squares containing RL to squares with an unaffected trabecular surface (RL/U). Classical ES/BS was assessed in parallel sections of the samples. The SEM, and to a lesser extent the qualitative different LM analysis, indicated a gender independent predominance of RL in subjects older than 50 years. This pilot study suggests that the new study design could be useful for acquiring quantitative RL data.

Adult↗

PubMed2005

An investigational study on the healing process of anterior spinal arthrodesis using a bioactive ceramic spacer and the change in load-sharing of spinal instrumentation.

STUDY DESIGN: Ceramic anterior lumbar interbody arthrodesis was performed using an in vivo sheep model. Observations of fusion status and the load-sharing of spinal instrumentation were studied at sequential intervals for 1 year after surgery. OBJECTIVES: To elucidate the healing process of spinal arthrodesis performed with a bioactive ceramic spacer and the change in load-sharing of anterior spinal instrumentation. SUMMARY OF BACKGROUND DATA: With the improved development of spinal instrumentation, anterior spinal arthrodesis has become a standard spinal reconstruction technique; however, the mechanistic basis underlying the healing process is not well documented. Moreover, it remains unclear how load-distribution through the fusion mass and spinal instrumentation change throughout the healing process. METHODS: Using 24 sheep, a two-level anterior lumbar interbody fusion (L2-L3, L4-L5) was performed using a smooth surface and a porous surface-modified bioactive ceramic, with each segment instrumented using a one-rod anterior spinal instrumentation system. Four animals each were killed at 2, 4, 8, 12, 24, and 52 weeks after surgery. Postmortem analysis included quantification of anterior rod strain under multidirectional flexibility testing and radiographic and histologic analyses of the arthrodesed segments. RESULTS: From 0 to 8 weeks after surgery, the bending strain of the rod gradually decreased despite no obvious bone formation. From 8 to 24 weeks after surgery, the rod strain markedly decreased with the development of bridging trabeculated bone formation between vertebral bodies. After 24 weeks after surgery, minimal changes were observed in rod strain; however, the fusion mass volumetrically increased with corresponding facet joint atrophy. The porous surface-modification of ceramic did not influence the histologic healing process, despite the improvement of interface osseous union rate. CONCLUSIONS: In anterior spinal arthrodesis, spinal instrumentation is mainly exposed to bending stress, with decreased load-sharing with corresponding development of the spinal fusion. Continuous bone remodeling of the anterior fusion mass results in concurrent decreases in spinal instrumentation and posterior spinal element load-transmission. The principal healing mechanism of ceramic anterior interbody spinal fusion is not an osseous union between the ceramic and vertebral body, but bridging bone formation around the ceramic, which directly connects the vertebral bodies above and below the disc.

Animals↗

PubMed2005

Dynamic three-dimensional undersampled data reconstruction employing temporal registration.

Dynamic 3D imaging is needed for many applications such as imaging of the heart, joints, and abdomen. For these, the contrast and resolution that magnetic resonance imaging (MRI) offers are desirable. Unfortunately, the long acquisition time of MRI limits its application. Several techniques have been proposed to shorten the scan time by undersampling the k-space. To recover the missing data they make assumptions about the object's motion, restricting it in space, spatial frequency, temporal frequency, or a combination of space and temporal frequency. These assumptions limit the applicability of each technique. In this work we propose a reconstruction technique based on a weaker complementary assumption that restricts the motion in time. The technique exploits the redundancy of information in the object domain by predicting time frames from frames where there is little motion. The proposed method is well suited for several applications, in particular for cardiac imaging, considering that the heart remains relatively still during an important fraction of the cardiac cycle, or joint imaging where the motion can easily be controlled. This paper presents the new technique and the results of applying it to knee and cardiac imaging. The results show that the new technique can effectively reconstruct dynamic images acquired with an undersampling factor of 5. The resulting images suffer from little temporal and spatial blurring, significantly better than a sliding window reconstruction. An important attraction of the technique is that it combines reconstruction and registration, thus providing not only the 3D images but also its motion quantification. The method can be adapted to non-Cartesian k-space trajectories and nonuniform undersampling patterns.

Algorithms↗

PubMed1995

A comparison of malreduction after plate and intramedullary nail fixation of forearm fractures.

A study was performed to compare the degree of malreduction after intramedullary nail and plate fixation of the forearm and to determine if the degree of malreduction was clinically significant. Eight matched pairs of forearms, including the wrist and elbow joints, were harvested from cadaver upper extremities. The forearms were put through a full range of motion, and physiological loads were applied to simulate those during normal use. Standardized anteroposterior and lateral radiographs of each forearm were obtained with the specimen intact, and after an osteotomy and internal fixation of one bone, both bones, and with gap at the osteotomy sites. In each forearm pair, plating was randomly performed in one specimen and intramedullary nailing was performed in the matching contralateral specimen. Forearm architecture was assessed by quantification of the magnitude and location of maximum radial bow and radial angulation. In this study, plate fixation was superior to nail stabilization in restoration of the normal radial architecture. Plating did not change any of the radiographic indices (magnitude and location of maximum radial bow and radial angulation) at any stage of testing. None of the radiographic indices was changed by nailing of only one of the forearm bones. The magnitude of maximum radial bow and the radial angulation were changed by nailing both forearm bones after osteotomy and both forearm bones with a gap (p < 0.05). Despite this, both techniques were well within the limits of what is radiographically acceptable for reduction.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Nails↗

PubMed2004

Clinical and biochemical study of 28 patients with mucopolysaccharidosis type VI.

This paper presents data collected by a Brazilian center in a multinational multicenter observational study of patients with mucopolysaccharidosis type VI (MPS VI), aiming at determining the epidemiological, clinical, and biochemical profile of these patients. Twenty-eight south-American patients with MPS VI were evaluated through medical interview, physical exam, echocardiogram, electrocardiogram, ophthalmologic evaluation, quantification of glycosaminoglycans (GAGs) in urine, and measurement of the activity of N-acetylgalactosamine-4-sulfatase (ARSB) in leukocytes. 92.9% of patients were Brazilian. Mean age at diagnosis and at evaluation was 48.4 months and 97.1 months, respectively. 88% of patients had onset of symptomatology before the age of 36 months. Consanguinity was reported by 27% of the families. Mean weight and height at birth were 3.481 kg and 51.3 cm, respectively. The most frequently reported clinical manifestations were short stature, corneal clouding, coarse facial features, joint contractures, and claw hands. All patients presented with echocardiogram changes as well as corneal clouding. Mean ARSB activity in leukocytes was 5.4 nmoles/h/mg protein (reference values: 72-174), and urinary excretion of GAGs was on average 7.9 times higher than normal. The number of clinical manifestations did not show a significant correlation with the levels of urinary GAGs nor with the ARSB activity. Also, no significant correlation was found between the levels of urinary GAGs and the ARSB activity. It was concluded that MPS VI has high morbidity and that, when compared with data published in the literature, patients in our study were diagnosed later and presented with a higher frequency of cardiological findings.

Brazil↗

PubMed2006

QT variability and HRV interactions in ECG: quantification and reliability.

In this paper, a dynamic linear approach was used over QT and RR series measured by an automatic delineator, to explore the interactions between QT interval variability (QTV) and heart rate variability (HRV). A low-order linear autoregressive model allowed to separate and quantify the QTV fractions correlated and not correlated with HRV, estimating their power spectral density measures. Simulated series and artificial ECG signals were used to assess the performance of the methods, considering a respiratory-like electrical axis rotation effect and noise contamination with a signal-to-noise ratio (SNR) from 30 to 10 dB. The errors found in the estimation of the QTV fraction related to HRV showed a nonrelevant performance decrease from automatic delineation. The joint performance of delineation plus variability analysis achieved less than 20% error in over 75% of cases for records presenting SNRs higher than 15 dB and QT standard deviation higher than 10 ms. The methods were also applied to real ECG records from healthy subjects where it was found a relevant QTV fraction not correlated with HRV (over 40% in 19 out of 23 segments analyzed), indicating that an important part of QTV is not linearly driven by HRV and may contain complementary information.

Algorithms↗

PubMed2003

Cortisol feedback state governs adrenocorticotropin secretory-burst shape, frequency, and mass in a dual-waveform construct: time of day-dependent regulation.

Quantification of in vivo pituitary hormone secretion requires simultaneous appraisal of implicit 1) secretory-burst waveform, mass, and stochastic pulse timing; 2) basal secretion; 3) biexponential elimination kinetics; and 4) random experimental error (Keenan DM, Licinio J, and Veldhuis JD. Proc Natl Acad Sci USA 98: 4028-4033, 2001). The present study extends this analytic formalism to allow for time of day-dependent waveform adaptation (burst-shape change) at statistically determinable boundary times. Thereby, we test the hypothesis that diurnal mechanisms and glucocorticoid negative feedback jointly govern distinctive facets of the burstlike secretion of ACTH. To this end, we reanalyzed intensively (10 min) sampled 24-h plasma ACTH concentration profiles collected previously under feedback-intact and drug-induced cortisol depletion in nine healthy adults. Akaiki information criterion-based model comparison favored dual (rather than single) secretory-burst representation of 24-h ACTH release in both the intact and low-cortisol setting in eight of nine subjects. Under feedback-intact conditions, analytically predicted waveform changepoints (median clock times 0611 and 1739) flanked an interval of elevated ACTH secretory-burst mass (P < 10-3). Experimental hypocortisolemia did not alter day/night boundaries, but 1) stimulated day ACTH secretory-burst mass (P < 10-3); 2) accelerated day ACTH secretory-burst frequency (P < 10-3); and 3) forced skewness of day ACTH secretory bursts toward more rapid initial release (P < 0.05). In contrast, the basal ACTH secretion rate and regularity of interpulse-interval lengths were invariant of day/night segmentation and cortisol availability. In conclusion, unknown diurnal factors and systemic cortisol concentrations codetermine ACTH secretory-burst waveform, frequency, and mass, whereas neither mechanism regulates basal ACTH release or regularity of the burst-renewal process.

Adaptation, Physiological↗

PubMed2004

[MRI monitoring of autologous hyaline cartilage grafts in the knee joint: a follow-up study over 12 months].

PURPOSE: To evaluate the suitability of different MR sequences for monitoring the stage of maturation of hyaline cartilage grafts in the knee joint and the early detection of complications like hypertrophy. In addition, it was analyzed whether indirect MR arthrography can indicate debonding of the graft. MATERIALS AND METHODS: MRI examinations were performed in 19 patients, aged 17 - 48 years, with autologous transplantation of a hyaline cartilage tissue graft after knee trauma. Examination dates were prior to transplantation to localize the defect, and 6 weeks, 3, 6 and 12 months after transplantation to control morphology and maturation of the autologous graft. Standard T2- and proton-density-weighted turbo spin echo (TSE) sequences and T1-weighted spin echo (SE) sequences were used, as well as gradient echo (GRE) sequences with and without magnetization transfer (MT) prepulses. In some cases, indirect MR arthrography was performed. RESULTS: Cartilage defect and the hyaline cartilage graft could be detected in all 19 patients. Hypertrophy of the graft could be found early in 3 patients and debonding in 1 patient. For depicting the graft a short time after surgery, T2-weighted TSE-sequences showed the best results. Six and 12 months after transplantation, spoiled 3D-GRE-sequences like FLASH3D (fast low angle shot) showed reduced artifacts due to magnetic residues from the surgery. Difference images from GRE-sequences with and without MT pulse provided high contrast between cartilage and surrounding tissue. The quantification of the MT effect showed an assimilation of the graft to the original cartilage within 12 months. Indirect MR arthrography showed subchondral contrast medium even 12 months after transplantation in 3 patients. CONCLUSION: MRI allows a reliable depiction of the hyaline graft and provides very early detection of complications like hypertrophy. The MT effect seems to be correlated with maturation of the graft and allows selective depiction of normal cartilage and engrafted cartilage.

Adolescent↗

PubMed1994

Detection of residual leukaemia more than 10 years after allogeneic bone marrow transplantation for chronic myelogenous leukaemia.

The clinical status of a homogeneous cohort of long-term survivors of allogeneic marrow transplantation was assessed and residual leukaemia was studied by reverse transcription polymerase chain reaction for leukaemia specific BCR-ABL mRNA. The group comprised 34 consecutive patients with CML in chronic phase treated by chemoradiotherapy and transplantation of bone marrow from HLA-identical sibling donors between February 1981 and December 1983 in the joint Hammersmith-Northwick Park programme. The probability of survival at 10 years was 59 +/- 17%. Eighteen of the 19 surviving (95%) patients have Karnofsky scores of 90 or 100% indicative of a good performance status. One of the survivors had evidence of relapse 6.5 years after transplant but has since been restored to complete remission by treatment with interferon-alpha followed by donor leucocyte transfusions. Surprisingly, 2 of the 19 patients who have been in remission for over 10 years have molecular evidence of persisting leukaemic cells. Quantification by competitive PCR indicated that the malignant clone persisted at low levels. The data suggest that the majority of long-term survivors after BMT for CML are in good health and may be regarded as cured. Some long-term survivors, however, may still harbour residual leukaemic cells and continued monitoring for late relapse is warranted. Late relapse is amenable to further therapy with leukocyte transfusions from the original marrow donor.

Adult↗

PubMed1997

Normal wrist kinematics and the analysis of the effect of various dynamic external fixators for treatment of distal radius fractures.

The purpose of this study was to evaluate the effect that external fixation devices used for distal radius fractures have on normal carpal kinematics, using high speed video data acquisition. Cadaver forearms were stabilized, allowing free excursion of the wrist for passive range of motion. Synergistic muscle tension was simulated by looping the extensor and flexor pairs of the wrist. Global wrist flexion and extension, intercarpal angles, and the instantaneous screw axis (ISA) were studied. These parameters allowed a quantification of normal carpal kinematics and comparison to the kinematics of the carpal bones with external fixators attached. This study shows that normal carpal kinematics during wrist flexion and extension do not have an ISA fixed in or limited to the capitate. In addition, the ISA data provide evidence that translational motion is a real and measurable component of normal carpal motion. This would change the understanding of carpal kinematics in previous studies that suggested that the center of rotation was fixed in the capitate. The proximal carpal (radiolunate) joint contributes more motion (has a greater rotation angle) in normal global wrist flexion and the midcarpal (capitolunate) joint contributes more motion in normal global wrist extension. In addition, the global range of motion and intercarpal joint angle of the wrist are limited with the application of any of the external fixators tested. None of the external fixators allowed normal ISA vector surfaces during wrist motion.

Adult↗

PubMed2002

Pedometer-determined ambulatory activity in individuals with type 2 diabetes.

This cross-sectional study presents the first normative data on pedometer-determined ambulatory activity, defined as steps/day, in 160 (98 males, 62 females; age=52.4 +/- 5.3 years; BMI=32.3 +/- 5.7) free-living individuals with type 2 diabetes. Participants took 6662 +/- 3077 steps per day, less than that reported in nondiabetic samples and more than that reported for samples living with more restrictive chronic conditions including claudication, joint replacement, chronic obstructive lung disease, and chronic heart failure. Steps/day and BMI were inversely and significantly correlated (r=-0.27, P<0.01). Further, there was a significant difference between BMI categories (from normal weight to obesity class III) with regard to steps/day (F=2.96, P<0.05). The difference was most apparent between the highest obesity classes (II and III) and normal weight categories. This data is useful for sample comparison purposes. In addition the standard deviation or variance estimates can be used to calculate samples sizes for intervention efforts. Objective quantification of ambulatory activity via simple and inexpensive pedometers permits researchers and practitioners to easily screen for level of activity along a continuum. This study opens the door for future research and clinical applications including identifying threshold values related to important health outcomes and evaluating incremental change due to various interventions in this population.

Body Mass Index↗

PubMed2004

Computer-assisted quantitative analysis of bone marrow edema of the knee: initial experience with a new method.

OBJECTIVE: The purpose of this study was to describe a largely observer-independent computer-assisted method for accurate quantitative analysis of bone marrow edema. MATERIALS AND METHODS: Ten patients with bone marrow edema of the knee were included in the study. Coronal STIR images of the affected knees were obtained using a 1.0-T MR scanner. Size and signal intensity of the bone marrow edema were assessed on the basis of gray-scale value analysis and calculation of a threshold value for differentiating normal and edematous bone marrow. All measurements were carried out three times for statistical analysis. RESULTS: The intraobserver coefficient of variation was 0.89% for the volume and 0.94% for the signal intensity of the bone marrow edema, showing the small impact of manual interference on results produced with this method. CONCLUSION: A computer-assisted method for quantification of bone marrow edema has been described. Intraobserver variation was very low, indicating excellent reproducibility of results. Although the method is too time-consuming for clinical use, it is recommended for research purposes.

Bone Marrow Diseases↗

PubMed1997

Effect of growth and development on cephalometric shapes in orthodontic patients: a Fourier analysis.

The age- and gender-related shape variations of the craniofacial skeleton in skeletal Class I children were quantified using a Fourier analysis on the pre-treatment lateral head films of 122 orthodontic patients (age range 7-15 years), who were subdivided into six groups for sex and age (2-year intervals). Seven landmarks representative of the maxillo-mandibular sagittal and vertical relationship were identified and digitized. The contiguous landmarks were connected by segments, the form was normalized with respect to its orientation and size, and a Fourier analysis of the contour was performed. Mean values of the cosine and sine coefficients of the first six harmonics in the sex and age classes were computed. The size-standardized outlines of the oldest boys were narrower and longer than the outlines of the youngest boys (differences at gonion, menton, sella and nasion). Shape differences between mean plots in girls were negligible. In the youngest patients, girls had a larger size-independent shape in the mandibular region; their shape was narrower (anterior-posterior direction) and longer (vertical direction) than male shape. In the oldest patients, boys had a larger size-independent shape at gonion, and a narrower shape at articulare and pogonion than girls. Size increased from the youngest to the oldest boys; size differences were not conspicuous in girls. Within an age class, male size was always larger than female. Fourier analysis allowed a global evaluation of the cephalometric forms, with separate quantifications of the age- and gender-related differences in size and shape.

Adolescent↗