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1.
J Clin Densitom ; 27(1): 101437, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38011777

RESUMO

INTRODUCTION: Professional guidance and standards assist radiologic interpreters in generating high quality reports. Initially DXA reporting Official Positions were provided by the ISCD in 2003; however, as the field has progressed, some of the current recommendations require revision and updating. This manuscript details the research approach and provides updated DXA reporting guidance. METHODS: Key Questions were proposed by ISCD established protocols and approved by the Position Development Conference Steering Committee. Literature related to each question was accumulated by searching PubMed, and existing guidelines from other organizations were extracted from websites. Modifications and additions to the ISCD Official Positions were determined by an expert panel after reviewing the Task Force proposals and position papers. RESULTS: Since most DXA is now performed in radiology departments, an approach was endorsed that better aligns with standard radiologic reports. To achieve this, reporting elements were divided into required minimum or optional. Collectively, required components comprise a standard diagnostic report and are considered the minimum necessary to generate an acceptable report. Additional elements were retained and categorized as optional. These optional components were considered relevant but tailored to a consultative, clinically oriented report. Although this information is beneficial, not all interpreters have access to sufficient clinical information, or may not have the clinical expertise to expand beyond a diagnostic report. Consequently, these are not required for an acceptable report. CONCLUSION: These updated ISCD positions conform with the DXA field's evolution over the past 20 years. Specifically, a basic diagnostic report better aligns with radiology standards, and additional elements (which are valued by treating clinicians) remain acceptable but are optional and not required. Additionally, reporting guidance for newer elements such as fracture risk assessment are incorporated. It is our expectation that these updated Official Positions will improve compliance with required standards and generate high quality DXA reports that are valuable to the recipient clinician and contribute to best patient care.


Assuntos
Densidade Óssea , Radiologia , Humanos , Absorciometria de Fóton , Sociedades Médicas
3.
J Clin Densitom ; 23(3): 426-431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31036446

RESUMO

BACKGROUND: Large changes in positioning of the global region of interest (ROI) influence the measurement of bone mineral density (BMD) in the hip and forearm regions. However, it is unknown whether minor shifts in the positioning of the bottom of the global hip ROI affect the measurement of total hip BMD. METHODS: The hip BMDs of 40 clinical densitometry patients were analyzed at baseline with the bottom of the global hip ROI positioned as usual, 10 mm distal to the base of the lesser trochanter (position 0). Then the hip was reanalyzed by shifting the bottom of the global hip ROI 1 mm proximally 10 times (positions +1 through +10) and then by shifting the bottom of the global hip ROI 1 mm distally 10 times (positions -1 through -10). The significance of the differences between mean values at the various distances from baseline was assessed using a Wilcoxon signed-rank test. RESULTS: The mean total hip area, bone mineral content and BMD decreased as the bottom of the global hip ROI was shifted proximally; the decrease was significant when shifted by even 1 mm (p < 0.001). The mean total hip area, bone mineral content and BMD increased as the bottom of the global hip ROI was shifted distally; the increase was significant when shifted by even 1 mm (p < 0.001). The change in BMD with each 1 mm shift was uniform across the range studied from positions +10 through -10, and was approx 0.54%/mm. When the least significant change was based on 40 pairs of measurements, where each pair was comprised of the baseline scan and the same scan at -1 position, the least significant change was 0.01 g/cm2. CONCLUSIONS: The BMD of the total hip is sensitive to even minor changes in the positioning of the bottom of the global hip ROI. Although a 1 mm change in the bottom of the global hip ROI positioning would make little difference in the reported T-score, it could easily affect the determination of significance in changes in BMD over time.


Assuntos
Absorciometria de Fóton/métodos , Densidade Óssea , Fêmur/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Idoso , Feminino , Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade
4.
J Clin Densitom ; 22(4): 453-471, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31400968

RESUMO

To answer important questions in the fields of monitoring with densitometry, dual-energy X-ray absorptiometry machine cross-calibration, monitoring, spinal cord injury, periprosthetic and orthopedic bone health, transgender medicine, and pediatric bone health, the International Society for Clinical Densitometry (ISCD) held a Position Development Conference from March 20 to 23, 2019. Potential topics requiring guidance were solicited from ISCD members in 2017. Following that, a steering committee selected, prioritized, and grouped topics into Task Forces. Chairs for each Task Force were appointed and the members were co-opted from suggestions by the Steering Committee and Task Force Chairs. The Task Forces developed key questions, performed literature searches, and came up with proposed initial positions with substantiating draft publications, with support from the Steering Committee. An invited Panel of Experts first performed a review of draft positions using a modified RAND Appropriateness Method with voting for appropriateness. Draft positions deemed appropriate were further edited and presented at the Position Development Conference meeting in an open forum. A second round of voting occurred after discussions to approve or reject the positions. Finally, a face-to-face closed session with experts and Task Force Chairs, and subsequent electronic follow-up resulted in 34 Official Positions of the ISCD approved by the ISCD Board on May 28, 2019. The Official Positions and the supporting evidence were submitted for publication on July 1, 2019. This paper provides a summary of the all the ISCD Adult and Pediatric Official Positions, with the new 2019 positions highlighted in bold.


Assuntos
Absorciometria de Fóton/normas , Densidade Óssea , Conferências de Consenso como Assunto , Fraturas Periprotéticas/diagnóstico , Traumatismos da Medula Espinal/diagnóstico , Pessoas Transgênero , Criança , Feminino , Humanos , Masculino , Fraturas Periprotéticas/terapia , Sociedades Médicas , Traumatismos da Medula Espinal/terapia
5.
Obesity (Silver Spring) ; 27(9): 1513-1519, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31318497

RESUMO

OBJECTIVE: The study aimed to investigate the association between BMI, waist circumference, and vertebral fracture (VF) risk in women. METHODS: This prospective study was conducted in 54,934 Nurses' Health Study participants. BMI was assessed biennially, and waist circumference was assessed in the year 2000. Self-reports of VF were confirmed by record review. BMI reflects lean body mass, and waist circumference reflects abdominal adiposity when included in the same regression model. RESULTS: This study included 536 VF cases (2002 to 2014). Compared with women with BMI of 21.0 to 24.9 kg/m2 , the multivariable-adjusted relative risk (RR) of VF for women with BMI ≥ 32.0 was 0.84 (95% CI: 0.61-1.14; Ptrend = 0.08). After further adjustment for waist circumference, the multivariable-adjusted RR of VF for women with BMI ≥ 32.0 was 0.70 (95% CI: 0.49-0.98; Ptrend = 0.003). Compared with women with waist circumference < 71.0 cm, the multivariable-adjusted RR of VF for women with waist circumference ≥ 108.0 cm was 1.76 (95% CI: 1.06-2.92; Ptrend = 0.01), and after further adjustment for BMI, the multivariable-adjusted RR of VF was 2.49 (95% CI: 1.44-4.33; Ptrend < 0.001). CONCLUSIONS: Greater lean body mass was independently associated with lower VF risk. Larger waist circumference was independently associated with higher VF risk. These findings suggest that fat distribution is an important predictor of VF and that avoiding central adiposity, as well as maintaining muscle mass, may potentially confer reduced risk of VF in older women.


Assuntos
Índice de Massa Corporal , Fraturas da Coluna Vertebral/etiologia , Circunferência da Cintura/fisiologia , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco , Fraturas da Coluna Vertebral/fisiopatologia
6.
J Clin Densitom ; 22(4): 544-553, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31327665

RESUMO

The indications for initial and follow-up bone mineral density (BMD) in transgender and gender nonconforming (TGNC) individuals are poorly defined, and the choice of which gender database to use to calculate Z-scores is unclear. Herein, the findings of the Task Force are presented after a detailed review of the literature. As long as a TGNC individual is on standard gender-affirming hormone treatment, BMD should remain stable to increasing, so there is no indication to monitor for bone loss or osteoporosis strictly on the basis of TGNC status. TGNC individuals who experience substantial periods of hypogonadism (>1 yr) might experience bone loss or failure of bone accrual during that time, and should be considered for baseline measurement of BMD. To the extent that this hypogonadism continues over time, follow-up measurements can be appropriate. TGNC individuals who have adequate levels of endogenous or exogenous sex steroids can, of course, suffer from other illnesses that can cause osteoporosis and bone loss, such as hyperparathyroidism and steroid use; they should have measurement of BMD as would be done in the cisgender population. There are no data that TGNC individuals have a fracture risk different from that of cisgender individuals, nor any data to suggest that BMD predicts their fracture risk less well than in the cisgender population. The Z-score in transgender individuals should be calculated using the reference data (mean and standard deviation) of the gender conforming with the individual's gender identity. In gender nonconforming individuals, the reference data for the sex recorded at birth should be used. If the referring provider or the individual requests, a set of "male" and "female" Z-scores can be provided, calculating the Z-score against male and female reference data, respectively.


Assuntos
Densidade Óssea , Conferências de Consenso como Assunto , Densitometria/normas , Osteoporose/diagnóstico , Pessoas Transgênero , Feminino , Humanos , Masculino
7.
Calcif Tissue Int ; 103(4): 380-387, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29754277

RESUMO

The few prospective studies examining the relation between proton pump inhibitor (PPI) use and risk of vertebral fracture (VF) suggest a higher risk, but the magnitude of the association has been inconsistent. Moreover, no prospective studies have examined the association between substantially longer duration of PPI use and VF risk. Our objective was to determine the association between PPI use, H2RA use, and incident clinical VF in women. We conducted a prospective study in 55,545 women participating in the Nurses' Health Study. PPI and H2RA use was assessed by questionnaire every 4 years. Self-reports of VF were confirmed by medical record. Our analysis included 547 incident VF cases (2002-2014). The multivariate adjusted relative risk (MVRR) of VF for women taking PPIs was 1.29 (95% CI 1.04-1.59) compared with non-users. Longer duration of PPI use was associated with higher VF risk (MVRR 1.16 [0.90-1.49] for < 4 years; 1.27 [0.93-1.73] for 4-7.9 years; 1.64 [1.02-2.64] for ≥ 8 years; ptrend = 0.01). The MVRR of VF for women taking H2RAs was 1.22 (0.90-1.67) compared with non-users. Longer duration of H2RA use was not associated with VF risk (MVRR 1.16 [0.88-1.53] for < 4 years; 0.98 [0.60-1.59] for ≥ 4 years; ptrend = 0.72). PPI use is independently associated with a modestly higher risk of VF and the risk increases with longer duration of use. There was no statistically significant association between H2RA use and VF risk. Our findings add to the growing evidence suggesting caution with PPI use, particularly with longer duration of use.


Assuntos
Antagonistas dos Receptores H2 da Histamina/efeitos adversos , Inibidores da Bomba de Prótons/efeitos adversos , Fraturas da Coluna Vertebral/epidemiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
8.
J Clin Densitom ; 21(4): 529-533, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29661688

RESUMO

Inconsistent positioning of patients and region of interest (ROI) is known to influence the precision of bone mineral density (BMD) measurements in the spine and hip. However, it is unknown whether minor shifts in the positioning of the ROI along the shaft of the radius affect the measurement of forearm BMD and its subregions. The ultradistal (UD-), mid-, one-third, and total radius BMDs of 50 consecutive clinical densitometry patients were acquired. At baseline the distal end of the ROI was placed at the tip of the ulnar styloid as usual, and then the forearm was reanalyzed 10 more times, each time shifting the ROI 1 mm proximally. No corrections for multiple comparisons were necessary since the differences that were significant were significant at p < 0.001. The UD-radius BMD increased as the ROI was shifted proximally; the increase was significant when shifted even 1 mm proximally (p < 0.001). These same findings held true for the mid- and total radius bone density, though the percent increase with moving proximally was significantly greater for the UD radius than for the other subregions. However, there was no significant change in the one-third radius BMD when shifted proximally 1-10 mm. Minor proximal shifts of the forearm ROI substantially affect the BMD of the UD-, mid- and total radius, while having no effect on the one-third radius BMD. Since the one-third radius is the only forearm region usually reported, minor proximal shifts of the ROI should not influence forearm BMD results significantly.


Assuntos
Absorciometria de Fóton/métodos , Densidade Óssea , Antebraço/diagnóstico por imagem , Posicionamento do Paciente , Idoso , Densidade Óssea/fisiologia , Feminino , Antebraço/fisiologia , Humanos , Pessoa de Meia-Idade
9.
J Clin Densitom ; 21(4): 524-528, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29254605

RESUMO

Previous publications suggested that the precision of the new Hologic Horizon densitometer might be better than that of the previous Discovery model, but these observations were confounded by not using the same participants and technologists on both densitometers. We sought to study this issue methodically by measuring in vivo precision in both densitometers using the same patients and technologists. Precision studies for the Horizon and Discovery models were done by acquiring spine, hip, and forearm bone mineral density twice on 30 participants. The set of 4 scans on each participant (2 on the Discovery, 2 on the Horizon) was acquired by the same technologist using the same scanning mode. The pairs of data were used to calculate the least significant change according to the International Society for Clinical Densitometry guidelines. The significance of the difference between least significant changes was assessed using a Wilcoxon signed-rank test of the difference between the mean square error of the absolute value of the differences between paired measurements on the Discovery (Δ-Discovery) and the mean square error of the absolute value of the differences between paired measurements on the Horizon (Δ-Horizon). At virtually all anatomic sites, there was a nonsignificant trend for the precision to be better for the Horizon than for the Discovery. As more vertebrae were excluded from analysis, the precision deteriorated on both densitometers. The precision between densitometers was almost identical when reporting only 1 vertebral body. (1) There was a nonsignificant trend for greater precision on the new Hologic Horizon compared with the older Discovery model. (2) The difference in precision of the spine bone mineral density between the Horizon and the Discovery models decreases as fewer vertebrae are included. (3) These findings are substantially similar to previously published results which had not controlled as well for confounding from using different subjects and technologists.


Assuntos
Absorciometria de Fóton/instrumentação , Absorciometria de Fóton/normas , Densidade Óssea , Absorciometria de Fóton/métodos , Idoso , Densidade Óssea/fisiologia , Competência Clínica , Antebraço/diagnóstico por imagem , Quadril/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Coluna Vertebral/diagnóstico por imagem , Estatísticas não Paramétricas
10.
J Clin Densitom ; 21(1): 125-129, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-27422238

RESUMO

The International Society for Clinical Densitometry guidelines recommend using locally derived precision data for spine bone mineral densities (BMDs), but do not specify whether data derived from L1-L4 spines correctly reflect the precision for spines reporting fewer than 4 vertebrae. Our experience suggested that the decrease in precision with successively fewer vertebrae is progressive as more vertebrae are excluded and that the precision for the newer Horizon Hologic model might be better than that for the previous model, and we sought to quantify. Precision studies were performed on Hologic densitometers by acquiring spine BMD in fast array mode twice on 30 patients, according to International Society for Clinical Densitometry guidelines. This was done 10 different times on various Discovery densitometers, and once on a Horizon densitometer. When 1 vertebral body was excluded from analysis, there was no significant deterioration in precision. When 2 vertebrae were excluded, there was a nonsignificant trend to poorer precision, and when 3 vertebrae were excluded, there was significantly worse precision. When 3 or 4 vertebrae were reported, the precision of the spine BMD measurement was significantly better on the Hologic Horizon than on the Discovery, but the difference in precision between densitometers narrowed and was no longer significant when 1 or 2 vertebrae were reported. The results suggest that (1) the measurement of in vivo spine BMD on the new Hologic Horizon densitometer is significantly more precise than on the older Discovery model; (2) the difference in precision between the Horizon and Discovery models decreases as fewer vertebrae are included; (3) the measurement of spine BMD is less precise as more vertebrae are excluded, but still quite reasonable even when only 1 vertebral body is included; and (4) when 3 vertebrae are reported, L1-L4 precision data can reasonably be used to report significance of changes in BMD. When 1 or 2 vertebrae are reported, precision data for 1 or 2 vertebrae, respectively, should be used, because the exclusion of 2-3 vertebrae significantly worsens precision.


Assuntos
Absorciometria de Fóton/instrumentação , Densidade Óssea , Vértebras Lombares/diagnóstico por imagem , Absorciometria de Fóton/normas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Reprodutibilidade dos Testes
11.
Am J Med ; 129(12): 1299-1306, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27542612

RESUMO

BACKGROUND: Vertebral fracture is the most common type of osteoporotic fracture. While thiazide diuretics, which are commonly prescribed for the treatment of hypertension, decrease calciuria, they may also induce hyponatremia, which has been associated with increased vertebral fracture risk. Loop diuretics increase calciuria, which would reduce bone mineral density and increase vertebral fracture risk, but they rarely cause hyponatremia. Recent studies on diuretics and fractures did not include or specifically examine vertebral fracture. The few studies of diuretics and vertebral fracture have been limited by cases defined by self-report or administrative data, relatively small number of cases, study design that was not prospective, and lack of long-term follow-up with updated information on diuretic use. METHODS: We conducted a prospective cohort study of thiazide diuretic use, loop diuretic use, and risk of incident clinical vertebral fracture in 55,780 women, 55-82 years of age, participating in the Nurses' Health Study, without a prior history of any fracture. Diuretic use was assessed by questionnaire every 4 years. Self-reported vertebral fracture was confirmed by medical record review. Cox proportional-hazards models were used to simultaneously adjust for potential confounders. RESULTS: Our analysis included 420 incident vertebral fracture cases documented between 2002 and 2012. The multivariate-adjusted relative risk of clinical vertebral fracture for women taking thiazides compared with women not taking thiazides was 1.47 (95% confidence interval, 1.18-1.85). The multivariate adjusted relative risk of vertebral fracture for women taking loop diuretics compared with women not taking loop diuretics was 1.59 (95% confidence interval, 1.12-2.25). CONCLUSION: Thiazide diuretics and loop diuretics are each independently associated with increased risk of vertebral fracture in women.


Assuntos
Densidade Óssea/efeitos dos fármacos , Cálcio/urina , Hipertensão/tratamento farmacológico , Hiponatremia/induzido quimicamente , Osteoporose/complicações , Inibidores de Simportadores de Cloreto de Sódio/efeitos adversos , Inibidores de Simportadores de Cloreto de Sódio e Potássio/efeitos adversos , Fraturas da Coluna Vertebral/etiologia , Comorbidade , Feminino , Inquéritos Epidemiológicos , Humanos , Hipertensão/epidemiologia , Hiponatremia/complicações , Pessoa de Meia-Idade , Análise Multivariada , Osteoporose/epidemiologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Risco , Autorrelato , Inibidores de Simportadores de Cloreto de Sódio/uso terapêutico , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico
12.
J Clin Densitom ; 19(2): 216-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26138207

RESUMO

It is unknown whether allowing patients to have BMD (bone mineral density) studies acquired while wearing radiolucent clothing adlib contributes appreciably to the measurement error seen. To examine this question, a spine phantom was scanned 30 times without any clothing, while draped with a gown, and while draped with heavy winter clothing. The effect on mean BMD and on SD (standard deviation) was assessed. The effect of clothing on mean or SD of the area was not significant. The effect of clothing on mean and SD for BMD was small but significant and was around 1.6% for the mean. However, the effect on BMD precision was much more clinically important. Without clothing the spine phantom had an least significant change of 0.0077 gm/cm(2), while when introducing variability of clothing the least significant change rose as high as 0.0305 gm/cm(2). We conclude that, adding clothing to the spine phantom had a small but statistically significant effect on the mean BMD and on variance of the measurement. It is unlikely that the effect on mean BMD has any clinical significance, but the effect on the reproducibility (precision) of the result is likely clinically significant.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Vestuário , Erros de Diagnóstico/prevenção & controle , Absorciometria de Fóton/métodos , Absorciometria de Fóton/normas , Humanos , Imagens de Fantasmas , Padrões de Referência , Reprodutibilidade dos Testes
13.
J Clin Densitom ; 19(2): 165-70, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25958033

RESUMO

We quantitated how often review of recent radiology studies provides information useful to the densitometrist. While preparing bone mineral density (BMD) reports on 1012 consecutive patients, radiology reports in electronic medical records (EMRs) for the previous 5 years at potentially relevant sites (lumbar spine X-rays, abdominal computed tomography (CT) scans, and so forth) were reviewed. When a study was found, it received a grade according to how relevant findings were to the BMD report: "1" for studies that were irrelevant, "2" for those that confirmed the impression formed from review of the BMD images, "3" for those that clarified the impression that was unclear after reviewing the BMD images, and "4" for those that revealed new relevant data when no abnormality was noted on review of the BMD images. A total of 562 patients (55.5%) had a radiologic study at a site of potential interest within the past 5 years. Fifty-three patients (5.2% of all patients) had a grade 4 study, 88 patients (8.7% of all patients) had a grade 3 study, and 185 patients (18.3% of all patients) had a grade 2 study. Two hundred sixty-four patients (25.8%) had a grade 2 or 3 study, and 299 (29.5%) had a grade 2-4 study. The radiographic study that was most likely to be found in patients' EMR was chest X-ray (34.7% of all patients), but it was also the one that was least likely to have any relevance to the reader; only 10.5% of the total chest X-rays were graded 2-4. The next most likely studies to be found in patients' EMR were abdominal CT scans (18.0% of all patients) and lumbar spine X-rays (14.4% of all patients), but these studies were much more likely to be useful to the reader, as 62.6% of abdominal CT scans and 78.1% of lumbar spine X-rays were graded 2-4. The likelihood of a patient having radiologic examinations in the EMR at sites potentially relevant to the BMD reader is high, but the likelihood that these clarify abnormalities noted on BMD is only moderate. Review of the EMR is unlikely to be relevant when the dual-energy X-ray absorptiometry images are normal.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Registros Eletrônicos de Saúde/estatística & dados numéricos , Registro Médico Coordenado , Absorciometria de Fóton/métodos , Absorciometria de Fóton/estatística & dados numéricos , Feminino , Quadril/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Registro Médico Coordenado/métodos , Registro Médico Coordenado/normas , Indicadores de Qualidade em Assistência à Saúde , Radiografia Abdominal/estatística & dados numéricos , Radiografia Torácica/estatística & dados numéricos , Gerenciamento do Tempo , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Estados Unidos
14.
Endocr Pract ; 20(12): 1315-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25100396

RESUMO

OBJECTIVE: We hypothesized that variability from year to year in how much of the bone map was filled in at the bottom of the spine region of interest (ROI) contributes substantially to variability in measurement of spine bone mineral density (BMD). METHODS: A total of 110 spine BMDs with defects in the bone mapping at the bottom were reanalyzed, with the only change being manually drawing a straight line across the bottom of the ROI and filling in the bone map. RESULTS: The mean (SD) change in area, bone mineral content, and BMD for total spine when the bottom of the bone map was filled in was 0.919 (0.411) cm2, 0.201 (0.121) g, and -0.0098 (0.0043) g/cm2, respectively, and all changes were significant (P<.0001). The largest individual change in total spine BMD with reanalysis was 0.0238 g/cm2, close to the least significant change (LSC) of 0.026 g/cm2 in our center. To quantify variability due to this change in analysis, we calculated an LSC(fill), in which the pairs of scans consisted of the same scan before and after filling in the bottom of the spine bone map, without any other change. The LSC(fill) attributable just to the reanalysis of missing bone map at the bottom of the spine was 0.021 g/cm2, suggesting substantial variance due to variability in mapping the bottom of the spine. CONCLUSION: When there is a noticeable defect in the bottom of the spine bone map, filling this defect in consistently eliminates a significant source of variability in analysis of spine BMDs and might allow us to achieve smaller LSCs.


Assuntos
Densidade Óssea , Absorciometria de Fóton
15.
Endocr Pract ; 20(8): 825-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24641929

RESUMO

OBJECTIVE: Lifting disabled patients onto a densitometer manually is dangerous for both the patient and the densitometry staff; using a ceiling lift is the preferred method of transfer. This system requires the use of a sling underneath the patient. Unless extra time is taken for its removal, the sling remains underneath the patient as bone mineral density (BMD) is measured. The aim of this study was to determine whether leaving this sling in place during scan acquisition affects the BMD measurement. METHODS: Measurements were taken of a spine phantom 30 times by itself, 30 times with a standard sling underneath the spine phantom, and 16 times with a disposable sling underneath the spine phantom. RESULTS: We found that mean BMD was significantly different versus the phantom alone when a sling was used, due to differences in area, bone mineral content, or both. The disposable sling affected the mean BMD to a much greater extent than did the standard sling (+1.9% vs. -0.41%; P for the difference between slings <.001). The standard sling did not increase the variance in the BMD measurement compared with the spine phantom alone, whereas the disposable sling did increase the variance in the BMD measurements. CONCLUSION: Commercially available ceiling-lift slings affect BMD measurements of spine phantoms. This effect is expected to persist when BMD is measured in patients and suggests that when lifting a patient onto the densitometer using these slings, it is best to take the time to remove the sling from under the patient after transfer and before scanning.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Pessoas com Deficiência , Movimentação e Reposicionamento de Pacientes/métodos , Humanos
16.
J Clin Densitom ; 16(4): 467-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24055260

RESUMO

Dual-energy X-ray absorptiometry (DXA) is the method of choice to assess fracture risk for women 65 yr and older and men 70 yr and older. The 2007 International Society for Clinical Densitometry Official Positions had developed guidelines for assessing bone density in younger women during and after the menopausal transition and in men 50-69 yr and the 2008 National Osteoporosis Foundation (NOF) guidelines recommended testing in postmenopausal women younger than 65 yr and men 50-69 yr only in the presence of clinical risk factors. The purpose of the 2013 DXA Task Force was to reassess the NOF guidelines for ordering DXA in postmenopausal women younger than 65 yr and men 50-69 yr. The Task Force reviewed the literature published since the 2007 Position Development Conference and 2008 NOF, reviewing clinical decision rules such as the Osteoporosis Screening Tool and FRAX and sought to keep recommendations simple to remember and implement. Based on this assessment, the NOF guidelines were endorsed; DXA was recommended in those postmenopausal women younger than 65 yr and men 50-69 yr only in the presence of clinical risk factors for low bone mass, such as low body weight, prior fracture, high-risk medication use, or a disease or condition associated with bone loss.


Assuntos
Absorciometria de Fóton/normas , Guias como Assunto , Programas de Rastreamento , Osteoporose/diagnóstico por imagem , Medição de Risco/métodos , Idoso , Densidade Óssea , Feminino , Humanos , Masculino , Osteoporose/metabolismo
17.
J Nucl Med ; 54(11): 1896-901, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24071505

RESUMO

UNLABELLED: For brown adipose tissue (BAT) to be effective at consuming calories, its blood flow must increase enough to provide sufficient fuel to sustain energy expenditure and also transfer the heat created to avoid thermal injury. Here we used a combination of human and rodent models to assess changes in BAT blood flow and glucose utilization. METHODS: (99m)Tc-methoxyisobutylisonitrile (MIBI) SPECT (n = 7) and SPECT/CT (n = 74) scans done in adult humans for parathyroid imaging were reviewed for uptake in regions consistent with human BAT. Site-directed biopsies of subcutaneous and deep neck fat were obtained for electron microscopy and gene expression profiling. In mice, tissue perfusion was measured with (99m)Tc-MIBI (n = 16) and glucose uptake with (18)F-FDG (n = 16). Animals were kept fasting overnight, anesthetized with pentobarbital, and given intraperitoneally either the ß3-adrenergic receptor agonist CL-316,243, 1 mg/kg (n = 8), or saline (n = 8) followed by radiotracer injection 5 min later. After 120 min, the mice were imaged using SPECT/CT or PET/CT. Vital signs were recorded over 30 min during the imaging. BAT, white adipose tissue (WAT), muscle, liver, and heart were resected, and tissue uptake of both (99m)Tc-MIBI and (18)F-FDG was quantified by percentage injected dose per gram of tissue and normalized to total body weight. RESULTS: In 5.4% of patients (4/74), (99m)Tc-MIBI SPECT/CT showed increased retention in cervical and supraclavicular fat that displayed multilocular lipid droplets, dense capillary investment, and a high concentration of ovoid mitochondria. Expression levels of the tissue-specific uncoupling protein-1 were 180 times higher in BAT than in subcutaneous WAT (P < 0.001). In mice, BAT tissue perfusion increased by 61% (P < 0.01), with no significant changes in blood flow to WAT, muscle, heart, or liver. CL-316,243 increased glucose uptake in BAT even more, by 440% (P < 0.01). CONCLUSION: Pharmacologic activation of BAT requires increased blood flow to deliver glucose and oxygen for thermogenesis. However, the glucose consumption far exceeds the vascular response. These findings demonstrate that activated BAT increases glucose uptake beyond what might occur by increased blood flow alone and suggest that activated BAT likely uses glucose for nonthermogenic purposes.


Assuntos
Tecido Adiposo Marrom/diagnóstico por imagem , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Tecido Adiposo Marrom/citologia , Tecido Adiposo Marrom/metabolismo , Adulto , Animais , Transporte Biológico , Circulação Sanguínea , Glucose/metabolismo , Humanos , Masculino , Camundongos , Imagem Multimodal , Transcriptoma
18.
J Clin Densitom ; 16(4): 482-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24063846

RESUMO

Vertebral fracture assessment (VFA) is a low-cost method of accurately identifying individuals who have clinically unrecognized or undocumented vertebral fractures at the time of bone density test. Because prevalent vertebral fractures predict subsequent fractures independent of bone mineral density and other clinical risk factors, their recognition is an important part of strategies to identify those who are at high risk of fracture, so that prevention therapies for those individuals can be implemented. The 2007 Position Development Conference developed detailed guidelines regarding the indications for acquisition of, and interpretation and reporting of densitometric VFA tests. The purpose of the 2013 VFA Task Force was to simplify the indications for VFA yet keep them evidence based. The Task Force reviewed the literature published since the 2007 Position Development Conference and developed prediction models based on 2 large cohort studies (the Study of Osteoporotic Fractures and the Osteoporotic Fractures in Men Study) and the densitometry database of the University of Chicago. Based on these prediction models, indications for VFA were reduced to a simplified set of criteria based on age, historical height loss, use of systemic glucocorticoid therapy, and self-reported but undocumented prior vertebral fracture.


Assuntos
Densitometria/normas , Guias de Prática Clínica como Assunto , Sociedades Médicas , Fraturas da Coluna Vertebral/diagnóstico por imagem , Densidade Óssea , Humanos , Radiografia , Fatores de Risco , Fraturas da Coluna Vertebral/etiologia
19.
Endocr Pract ; 16(1): 30-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19703805

RESUMO

OBJECTIVE: To evaluate whether introduction of a densitometry workflow, data-storage, and reporting software system would result in streamlined workflow with fewer expenses and quicker result turnaround time. METHODS: BoneStation was implemented March 30, 2009, in a large, urban, tertiary referral center performing more than 6000 bone mineral density studies annually at 3 different geographic sites. The times of scan acquisition, report preparation, and final signature in the online medical record were recorded, and the delays from scan to report and from scan to final signature in the online medical record were calculated for each patient during 2 representative weeks before (n = 274) and 2 weeks after (n = 235) implementation of BoneStation. RESULTS: Use of BoneStation reduced time from scan to report from 2.11 +/- 0.16 days to 0.46 +/- 0.05 days (P<.001). BoneStation saved our practice $8.94 per scan, while costing only $3 per scan, resulting in net savings. Considering that the total reimbursement from Medicare in 2010 for dual-energy x-ray absorptiometry is projected to be $55.44, this constitutes cost savings of 10.7% of the total reimbursement. CONCLUSION: The introduction of a specialized electronic medical system for data storage and reporting reduced costs and improved result turnaround time in a densitometry practice.


Assuntos
Densidade Óssea , Armazenamento e Recuperação da Informação/economia , Software , Absorciometria de Fóton , Humanos , Armazenamento e Recuperação da Informação/métodos , Fatores de Tempo
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