Dual-energy X-ray Absorptiometry T-scores Research Articles

Measurement of lumbar vertebral body attenuation at PET-CT is a reliable method of diagnosing osteoporosis.

This study investigates the potential of positron emission tomography-computed tomography (PET-CT) as a reliable tool for the diagnosis of osteoporosis, using attenuation values as a marker for bone mineral density (BMD) assessment. We retrospectively identified 305 patients who underwent both PET-CT and dual-energy X-ray absorptiometry (DEXA) within a six-month interval at a tertiary healthcare centre. Attenuation values were measured from the first lumbar vertebra (L1) on noncontrast CT images acquired during PET-CT scans. These values were then compared with corresponding DEXA T-scores to determine their diagnostic performance. Statistical analyses, including one-way Analysis of Variance (ANOVA), Pearson correlation, and receiver operating characteristic (ROC) curve analysiswere employed to assess the correlation between PET-CT attenuation values and DEXA-defined osteoporosis. The mean Hounsfield units (HU) differed significantly between groups classified by DEXA as osteoporosis, osteopenia, or normal BMD (P < 0.001). A strong correlation was found between HU and DEXA T-scores (Pearson coefficient=0.65). Using logistic regression, we identified HU thresholds of 120 for 90% sensitivity and 98 for 90% specificity. The optimal balanced threshold was 109 HU, achieving both 80% sensitivity and specificity. The ROC curve for the model showed an area under the curve (AUC) of 0.88, indicating high diagnostic accuracy. PET-CT can effectively screen for osteoporosis, offering a noninvasive, opportunistic diagnostic tool that requires no additional radiation exposure or resources. This study establishes 109 HU as the optimal threshold for diagnosing osteoporosis on PET-CT, providing a significant opportunity for early intervention and improved patient care.

Evaluation of lumbar vertebral bone quality using T1-weighted MRI: Can it differentiate normal, osteopenia, and osteoporosis?

Osteoporosis, a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration, poses a significant public health challenge globally. While the gold standard for diagnosing osteoporosis is dual-energy X-ray absorptiometry (DXA), its use is limited by factors like spinal deformities and artifacts. This study aims to explore the potential of routine T1-weighted MRI sequences in predicting osteopenia and osteoporosis through the vertebral bone signal (VB) to cerebrospinal fluid signal (CSF) ratio. We conducted a retrospective study of patients who underwent both DXA and lumbar MRI within a six-month interval between 2020 and 2023. Excluding patients with known vertebral fractures, bone tumors, heterogeneous bone marrow, or endplate signal changes due to degenerative alterations, we divided the patients into normal, osteopenic, and osteoporotic groups based on their DXA T-scores. The T1-weighted sagittal MRI sequences were analyzed, and the T1 VB/CSF ratios were calculated for each vertebra (L1-L4). The study included 376 patients, with an average age of 60.8 ± 9.1 years. Statistically significant differences were found in the T1 VB/CSF ratios across the normal, osteopenic, and osteoporotic groups (p < 0.05). The L1 vertebra demonstrated the highest diagnostic performance for predicting osteoporosis, with an AUC of 0.75, a sensitivity of 88.1 %, and a specificity of 84.5 %. For differentiating osteopenia from normal, the L1 vertebra achieved an AUC of 0.68, with a sensitivity of 78.2 % and a specificity of 76.4 %. The optimal cut-off values were determined as 3.62 for osteopenia and 3.80 for osteoporosis. The T1 VB/CSF ratio derived from routine lumbar MRI sequences provides a promising, radiation-free tool for opportunistic screening of osteoporosis and osteopenia. Given the frequent use of lumbar MRI for patients with spinal complaints, this method could facilitate early diagnosis and intervention, guiding high-risk patients towards further DXA evaluation and management.

Hounsfield unit values are a better predictor than DXA T-score for adjacent vertebral fracture following balloon kyphoplasty.

Hounsfield unit values (HU) are known to correlate with dual-energy X-ray absorptiometry (DXA), and they are gaining attention as a new method for assessing Bone mineral density (BMD) that is not affected by the limitations of DXA, such as degeneration, scoliosis, and vascular calcification. The purpose of this study was to compare the efficacy of HU and DXA T-scores in predicting adjacent vertebral fractures (AVF) following balloon kyphoplasty (BKP) using the same computed tomography and DXA at one institution. The study included 84 cases (20 males, 64 females, mean age 79.3±6.9) who underwent BKP for osteoporotic vertebral fractures. Cases were divided into two groups based on the presence or absence of AVF within 2 months postoperatively. BMD assessment included DXA T-scores (lumbar spine, hip, the lowest), HU of the fractured adjacent vertebra (adjacent-HU) and HU of the L1 vertebra (L1-HU). Logistic regression analysis was performed to identify risk factors for AVF, and the accuracy of AVF prediction was evaluated using the area under the receiver operating characteristics curve (AUC). AVF occurred in 23 of the 84 cases (27.4%) within 2 months postoperatively. In the logistic regression analysis, T-score was not identified as an independent risk factor, but L1-HU was identified as an independent risk factor for AVF (odds ratio: 0.982, P=0.044∗). The AUC for predicting AVF was 0.515, 0.568, and 0.510 for T-score (lumbar spine, hip, the lowest), and 0.551 for adjacent-HU. The highest AUC was observed for L1-HU at 0.629 (95% confidence interval 0.495-0.764). In the risk assessment of AVF, L1-HU was a better evaluation method than DXA T-score.

Normative vertebral deformity measurements in a clinically relevant population using magnetic resonance imaging.

Osteoporosis is the leading cause of vertebral fractures. Dual-energy X-ray absorptiometry (DXA) and radiographs are traditionally used to detect osteoporosis and vertebral fractures/deformities. Magnetic resonance imaging (MRI) can be utilized to detect the relative severity of vertebral deformities using three-dimensional information not available in traditional DXA and lateral two-dimensional radiography imaging techniques. To generate normative vertebral parameters in women using MRI and DXA scans, determine the correlations between MRI-calculated vertebral deformities and age, DXA T-scores, and DXA Z-scores, and compare MRI vertebral deformity values with radiography values previously published in the literature. This study is a retrospective vertebral morphometric analysis conducted at our institution. The patient sample included MR images from 1638 female patients who underwent both MR and DXA imaging between 2005 and 2014. Biconcavity, wedge, crush, anterior height (Ha)/posterior height (Hp), and middle height (Hm)/posterior height values were calculated from the MR images of the patient's vertebrae. Associations between vertebral deformity values, patient age, and DXA T-scores were analyzed using Spearman correlation. The MRI-derived measurements were compared with radiograph-based calculations from population-based data compiled from multiple studies. Age was positively correlated with lumbar Hm/Hp (P = 0.04) and thoracic wedge (P = 0.03) and biconcavity (P = 0.001) and negatively correlated with thoracic Ha/Hp (P = 0.002) and Hm/Hp (P = 0.001) values. DXA T-scores correlated positively with lumbar Hm/Hp (P < 0.0001) and negatively with lumbar wedge (P = 0.046), biconcavity (P < 0.0001), and Ha/Hp (P = 0.046) values. Qualitative analysis revealed that Ha/Hp differed between MRI and radiography population-based data by no more than 0.3 and Hm/Hp by a maximum of 1.2. Compared with traditional imaging techniques, MRI detects vertebral deformities with high accuracy and reliability. It may be a sensitive, ionizing, radiation-free tool for use in clinical settings.

Age-dependent changes in CT vertebral attenuation values in opportunistic screening for osteoporosis: a nationwide multi-center study.

To examine how vertebral attenuation changes with aging, and to establish age-adjusted CT attenuation value cutoffs for diagnosing osteoporosis. This multi-center retrospective study included 11,246 patients (mean age ± standard deviation, 50 ± 13 years; 7139 men) who underwent CT and dual-energy X-ray absorptiometry (DXA) in six health-screening centers between 2022 and 2023. Using deep-learning-based software, attenuation values of L1 vertebral bodies were measured. Segmented linear regression in women and simple linear regression in men were used to assess how attenuation values change with aging. A multivariable linear regression analysis was performed to determine whether age is associated with CT attenuation values independently of the DXA T-score. Age-adjusted cutoffs targeting either 90% sensitivity or 90% specificity were derived using quantile regression. Performance of both age-adjusted and age-unadjusted cutoffs was measured, where the target sensitivity or specificity was considered achieved if a 95% confidence interval encompassed 90%. While attenuation values declined consistently with age in men, they declined abruptly in women aged > 42 years. Such decline occurred independently of the DXA T-score (p < 0.001). Age adjustment seemed critical for age ≥ 65 years, where the age-adjusted cutoffs achieved the target (sensitivity of 91.5% (86.3-95.2%) when targeting 90% sensitivity and specificity of 90.0% (88.3-91.6%) when targeting 90% specificity), but age-unadjusted cutoffs did not (95.5% (91.2-98.0%) and 73.8% (71.4-76.1%), respectively). Age-adjusted cutoffs provided a more reliable diagnosis of osteoporosis than age-unadjusted cutoffs since vertebral attenuation values decrease with age, regardless of DXA T-scores. Question How does vertebral CT attenuation change with age? Findings Independent of dual-energy X-ray absorptiometry T-score, vertebral attenuation values on CT declined at a constant rate in men and abruptly in women over 42 years of age. Clinical relevance Age adjustments are needed in opportunistic osteoporosis screening, especially among the elderly.

Vertebral Bone Quality Score as a Predictor of Subsequent Fractures After Cement Augmentation for Osteoporotic Vertebral Compression Fracture.

Dual-energy X-ray absorptiometry (DXA) T-scores have been shown to predict fragility fractures in population-based studies. Recently, a novel MRI-based vertebral bone quality (VBQ) score has been proposed, showing better predictability for fragility fractures compared with DXA T-scores. The aim of this study was to explore the correlation between VBQ scores and DXA T-scores and to determine the impact of VBQ scores on the risk of subsequent fragility fractures after cement augmentation for osteoporotic vertebral compression fracture (OVCF). Between January and December 2018, 251 consecutive patients who received cement augmentation for OVCF were included in the study. VBQ scores were calculated using noncontrast T1-weighted MRI. Correlations between VBQ and T-scores were assessed. Patients were divided into 2 groups based on the presence or absence of subsequent fragility fractures after cement augmentation: (1) no Subsequent fracture group and (2) subsequent fracture group. Comparisons between the groups were conducted, and risk factors of subsequent fractures were evaluated using multivariable logistic regression analysis. Of the patients, 42 (16.7%) experienced subsequent fractures after cement augmentation. The VBQ score showed moderate correlations with the T-score of the hip (r = -0.523, P < .001) and the T-score of the lumbar spine (r = -0.383, P < .001). The subsequent fracture group had a significantly higher VBQ score (4.02 ± 0.56 vs 3.52 ± 0.62, P < .001) and a worse T-score of hip (-3.06 ± 1.28 vs -2.42 ± 0.98, P = .004). In the multivariable analysis, the VBQ score was the only independent predictor of subsequent fractures with 2.799 odds ratio (1.342 to 5.841, P = .006). In patients who received cement augmentation for OVCF, the VBQ score is significantly correlated with the DXA T-score and may be a more reliable predictor of subsequent fragility fractures.

Effect of contrast media on CT bone density assessment: comparative analysis of low-dose chest CT and abdominopelvic CT

Detecting individuals with low bone mineral density (BMD) before clinical fractures occur may help improve the outcomes of osteoporosis and osteopenia. Although computed tomography (CT) is useful for opportunistic BMD measurement, the modality most suitable for opportunistic screening remains unclear. In this retrospective study, we compared the diagnostic performance of low-dose chest CT (LDCT) and contrast-enhanced abdominopelvic CT (APCT) for measuring BMD at L1 level using dual-energy X-ray absorptiometry (DEXA) as a reference in individuals who underwent LDCT, APCT, and DEXA assessments on the same day. We included 512 individuals (median age: 60 years; interquartile range, 55−65 years; 307 men). Both LDCT (r = 0.706; P < 0.001) and APCT (r = 0.643; P < 0.001) exhibited strong correlation with DEXA T-scores. As T-scores decreased, the relative difference between LDCT and APCT Hounsfield unit values increased (b = − 6.456; P < 0.001). LDCT outperformed APCT in diagnosing both osteoporosis (AUC, 0.865 vs. 0.833; P = 0.035) and low BMD (AUC, 0.844 vs. 0.815; P = 0.006), which may be attributable to the greater effect of intravenous contrast media on CT scan characteristics in individuals with lower T-scores. These results may help inform the selection of imaging methods suitable for screening.

Opportunistic Screening for Low Bone Mineral Density in Routine Computed Tomography Scans: A Brazilian Validation Study

Introduction/background: Osteoporotic fractures are a major health concern worldwide due to high mortality rates, deterioration in quality of life, and elevated healthcare costs related to hospital treatment. However, most patients who sustain an osteoporotic fracture have never been formally screened for osteoporosis. Opportunistic screening of osteoporosis through conventional computed tomography (CT) scans performed for unrelated reasons could help identify patients with low bone mass. There are currently no studies validating the opportunistic screening of low bone mass through CT in South America. The aim of our study is to assess whether conventional CT scans could be used for the opportunistic screening of osteopenia and osteoporosis in Brazilian patients.Methodology: Patients who underwent unenhanced CT and dual-energy X-ray absorptiometry (DXA) scans within a six-month interval were assessed retrospectively. Mean CT attenuation was measured in the first lumbar vertebra (L1) in axial, coronal, and sagittal planes and compared to their respective DXA T-scores; vertebral fractures were assessed in the sagittal plane. Potential thresholds suggestive of low bone mass density (BMD) were established using receiver operating characteristics analysis.Results: 491 patients were included (93.2 % female; mean age of 64.1 ± 9.8 years; mean interval of 63.5 days between scans). Mean L1 CT attenuation was significantly lower in osteopenic and osteoporotic patients in all CT planes (p < 0.001). Positive linear correlations were found between DXA T-scores and the average L1 attenuations in all CT planes (p < 0.001). An average L1 attenuation equal or below 100 Hounsfield Units (HU) in the sagittal plane identified low BMD (osteopenia or osteoporosis) with a specificity of 96.3 % and a positive predictive value of 96 %. In contrast, an average L1 attenuation above 180 HU demonstrated a sensitivity of 97.6 % and a negative predictive value of 94.9 % for detecting osteoporosis. Patients with L1 sagittal attenuation at or below 100 HU exhibited a significantly higher prevalence of vertebral fractures (prevalence ratio: 8.67; p < 0.001). An online calculator based on the results of this study is freely available at www.osteotc.com.br.Conclusions: Routine CT scans can identify probable low bone density (osteopenia or osteoporosis) in Brazilian patients without additional costs or radiation exposure. Opportunistic CT screening does not substitute formal bone mineral density assessment; instead, it assists in identifying patients who may benefit from it.

Accuracy of Phantomless Calibration of Routine Computed Tomography Scans for Opportunistic Osteoporosis Screening in the Spine Clinic.

Diagnostic accuracy study. To establish a simple method of phantomless bone mineral density (BMD) measurement by using preoperative lumbar Computed Tomography (CT) scans, and compare the accuracy of reference tissue combinations to diagnose low BMD against uncalibrated Hounsfield units (HUs). HUs are used as a measure of BMD; however, associations between HU and T-scores vary widely. Quantitative CT (qCT) scans are more accurate, but they require density calibration with an object of known density (phantom), which limits feasibility. As an emerging technique, phantomless (internal) calibration of routine CT scans may provide a good opportunity for screening. Patients who were scheduled to undergo lumbar surgery, with a preoperative CT scan, and a dual-energy x-ray absorptiometry (DXA) scan within six months were included. Four tissues were selected for calibration: subcutaneous adipose (A), erector spinae (ES), psoas (P) and aortic blood (AB). The HUs of these tissues were used in linear regression against ground-truth values. Calibrations were performed by using two different internal tissues at a time to maintain simplicity and in-office applicability.Volumetric bone mineral densities (vBMD) derived from internally calibrated CT scans were analyzed for new threshold values for low bone density. Areas under the curve (AUC) were calculated with 95% confidence intervals (CI). 45 patients were included (M/F=10/35, mean age:63.3). Calibrated vBMDs had stronger correlations with DXA T-scores when compared with HUs, with L2 exhibiting the highest coefficients. Calibration by using A and ES with the threshold of 162mg/cm3 had a sensitivity of 90% in detecting low BMD (AUC=0.671). This novel method allows simple, in-office calibration of routine preoperative CT scans without the use of a phantom. Calibration using adipose and erector spinae with a threshold of 162mg/cm3 is proposed for low bone density screening with high sensitivity (90%). Level III.

An Automated Assessment Method for Chronic Kidney Disease–Mineral and Bone Disorder (CKD-MBD) Utilizing Metacarpal Cortical Percentage

Chronic kidney disease–mineral and bone disorder (CKD-MBD) frequently occurs in hemodialysis patients and is a common cause of osteoporosis. Regular dual-energy X-ray absorptiometry (DXA) scans are used to monitor these patients, but frequent, cost-effective, and low-dose alternatives are needed. This study proposes an automatic CKD-MBD assessment model using histogram equalization and a squeeze-and-excitation block-based residual U-Net (SER-U-Net) with hand diagnostic radiography for preliminary classification. The process involves enhancing image contrast with histogram equalization, extracting features with the SE-ResNet model, and segmenting metacarpal bones using U-Net. Ultimately, a correlation analysis is carried out between the calculated dual metacarpal cortical percentage (dMCP) and DXA T-scores. The model’s performance was validated by analyzing clinical data from 30 individuals, achieving a 93.33% accuracy in classifying bone density compared to DXA results. This automated method provides a rapid, effective tool for CKD-MBD assessment in clinical settings.

Evaluation of the modified MRI vertebral bone quality score for bone quality in lumbar degenerative disorders.

The traditional VBQ scoring method may lead to overestimation due to the concentration of intravertebral fat and vascular structures in the posterior half of vertebral bodies, potentially resulting in false-positive outcomes. This study aims to modify the measurement method of VBQ score (Modified-VBQ) and evaluate its effectiveness in evaluating bone quality of lumbar degenerative diseases. Retrospective analysis was conducted on clinical data from patients undergoing lumbar surgery for degenerative diseases between September 2022 and September 2023. Preoperative lumbar t1-weighted Magnetic resonance imaging was used for both modified and traditional VBQ scoring. Computed tomography (CT) images and dual-energy X-ray absorptiometry (DEXA) data were collected through the picture archiving and communication system. The effectiveness of the modified VBQ score was evaluated, considering P < 0.05 as statistically significant. The study included 212 patients, revealing a significant difference between the modified VBQ and VBQ scores (P < 0.0001). Notably, patients with a history of hyperlipidemia exhibited a significant difference between the two scores (P = 0.0037). The area under the ROC curve (AUC) for the modified VBQ was 0.86, surpassing the VBQ score (AUC = 0.74). Linear regression analysis demonstrated a moderate to strong correlation between the modified VBQ and DEXA T-score (r = - 0.49, P < 0.0001) and a high correlation with CT Hounsfield units (HU) values (r = - 0.60, P < 0.0001). The modified VBQ score provides a simple, effective, and relatively accurate means of assessing bone quality in lumbar degenerative diseases. Preoperative implementation of the modified VBQ score facilitates rapid screening for patients with abnormal bone quality.

Ultrashort echo time MRI detects significantly lower collagen but higher pore water in the tibial cortex of female patients with osteopenia and osteoporosis.

Ultrashort echo time (UTE) MRI can quantify the major proton pool densities in cortical bone, including total (TWPD), bound (BWPD), and pore water (PWPD) proton densities, as well as the macromolecular proton density (MMPD), associated with the collagen content, which is calculated using macromolecular fraction (MMF) from UTE magnetization transfer (UTE-MT) modeling. This study aimed to investigate the differences in water and collagen contents in tibial cortical bone, between female osteopenia (OPe) patients, osteoporosis (OPo) patients, and young participants (Young). Being postmenopausal and above 55yr old were the inclusion criteria for OPe and OPo groups. The tibial shaft of 14 OPe (72.5 ± 6.8yr old), 31 OPo (72.0 ± 6.4yr old), and 31 young subjects (28.0 ± 6.1yr old) were scanned using a knee coil on a clinical 3T scanner. Basic UTE, inversion recovery UTE, and UTE-MT sequences were performed. Investigated biomarkers were compared between groups using Kruskal-Wallis test. Spearman's correlation coefficients were calculated between the TH DXA T-score and UTE-MRI results. MMF, BWPD, and MMPD were significantly lower in OPo patients than in the young group, whereas T1, TWPD, and PWPD were significantly higher in OPo patients. The largest OPo/Young average percentage differences were found in MMF (41.9%), PWPD (103.5%), and MMPD (64.0%). PWPD was significantly higher (50.7%), while BWPD was significantly lower (16.4%) in OPe than the Young group on average. MMF was found to be significantly lower (27%) in OPo patients compared with OPe group. T1, MMF, TWPD, PWPD, and MMPD values significantly correlated with the TH DXA T-scores (provided by the patients and only available for OPe and OPo patients). DXA T-score showed the highest correlations with PWPD (R = 0.55) and MMF (R = 0.56) values. TWPD, PWPD, and MMF estimated using the UTE-MRI sequences were recommended to evaluate individuals with OPe and OPo.

Bone density measured on sagittal reconstructed CT is highly correlated with axial CT but both measurements are only moderately correlated with DEXA T-scores

BackgroundDuring the preoperative evaluation of a patient being considered for spinal surgery, Dual-energy x-ray absorptiometry (DEXA) has been traditionally used to diagnose poor bone mineral density (BMD) as a risk factor. As ordering a DEXA can add cost and delay diagnosis, spine surgeons have more recently began to use Hounsfield Units (HU) measured on computed tomography scans (CT) as a measure of BMD. The aim of our study was to evaluate associations between DEXA and HU on lumbar spine CT scans. MethodsForty-two patients (32 female, 10 male, mean age = 67.7 years) with DEXA and lumbar spine CT scans performed within one year of each other were identified. DEXA T-scores were collected from the hip, forearm and L1-L4. HU was determined using the maximum region of interest within the cancellous area in the mid-vertebral body from L1-L4 in the sagittal and axial planes. ResultsUsing the lowest T-score, 8 (19 %) cases were osteoporotic and 25 (60 %) were osteopenic. Statistically significant differences in HU were seen in osteoporotic cases (Axial HU = 59.2, Sagittal HU = 61.1, p = 0.006) compared to osteopenic (Axial HU = 119.8, Sagittal HU = 122.9) and normal cases (Axial HU = 141.2, Sagittal HU = 142.3). There were moderate associations between the spine T-scores and CT HUs (Axial HU:r2 = 0.50, Sagittal HU:r2 = 0.49, p < 0.001), weak associations between the Axial HU (r2 = 0.48, p < 0.000) and Sagittal HU (r2 = 0.48, p < 0.000) with hip T-scores, and no correlations with forearm T-scores. There were strong associations between Axial HU and Sagittal HU (r2 = 0.98, p < 0.001). Clinical relevanceThe results of the current study show a strong association between the sagittal and axial vertebral HU measurements, which supports the clinical use of either measurement technique. The weak correlation between T-scores and HU is consistent with prior studies and warrants future studies to determine which modality will better predict postoperative mechanical failures in patients undergoing spinal surgery. Level of EvidenceIII.

The Canal Bone Ratio: A Novel Indicator for Opportunistic Osteoporosis Screening in Adult Spinal Deformity Patients Through Radiographs.

Retrospective diagnostic study. To evaluate the utility of quantitative assessment of bone density using proximal femoral morphological parameters based on full-spine x-rays. CT and MRI are commonly utilized methods for opportunistic assessment of bone density. However, there is currently a lack of means to quantitatively assess bone density in adult spinal deformity (ASD) patients through radiographs. Data collection involved medical records of ASD patients treated at our hospital. Patients were categorized into osteoporotic and nonosteoporotic groups based on dual-energy x-ray absorptiometry T-scores. Demographic information, radiographic parameters (canal bone ratio, canal bone ratio (CBR); cortical bone thickness, cortical bone thickness (CBT)), Hounsfield units, and vertebral body quality (VBQ) scores were compared. Pearson correlation analysis was conducted to assess the correlation between CBR, CBT, and T-scores. Multiple linear regression analysis identified independent predictors of bone density T-scores. Receiver operating characteristic curves and area under the curve calculations were performed to investigate the predictive performance for osteoporosis. A total of 102 patients were included, with the osteoporotic group showing larger CBR and smaller CBT compared with the nonosteoporotic group. Proximal femoral morphological parameters exhibited the strongest correlation with total hip T-scores. Advanced age (β=-0.028, 95% CI=-0.054 to -0.002, P =0.032), low BMI (β=0.07, 95% CI=0.014-0.126, P =0.015), and high CBR (β=-7.772, 95% CI=-10.519 to -5.025, P <0.001) were identified as independent predictors of low bone density. Receiver operating characteristic analysis demonstrated that CBR had a similar osteoporosis screening capability as Hounsfield units, followed by CBT and VBQ scores. The utilization of CBR from full-spine x-rays is a simple and effective osteoporosis screening indicator for ASD patients, facilitating bone density assessments by spine surgeons for all attending patients.

Diagnostic Value of Radiographic Singh Index Compared to Dual-Energy X-Ray Absorptiometry Scan in Diagnosing Osteoporosis: A Systematic Review.

Since various medications can control the rate of fractures and subsequent complications of osteoporosis, the early detection of the disease is crucial. This systematic study aimed to compare the diagnostic accuracy of Singh index (SI) with dual-energy X-ray absorptiometry (DEXA) as a benchmark standard for diagnosing osteoporosis. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) were utilized in the current study. A detailed search was carried out using PubMed and Scopus from inception to 30 May 2022. Examining quality of the studies was performed by the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). A total of 22 studies were included. In general, 50% of the studies considered SI a poor screening tool for detecting osteoporosis due to a negligible inter-observer agreement between SI and DEXA or a poor correlation of SI with the bone mineral density (BMD) category or DEXA T-score. A moderate inter-observer agreement was reported for SI in 5 (55.6%) studies. Among the studies assessing the sensitivity and specificity of SI compared to DEXA (n=13), six studies estimated a low sensitivity for SI. While there is supporting evidence indicating the potential usefulness of SI for predicting femoral neck fractures in individuals with suspected osteoporosis, numerous studies challenge its reliability and diagnostic value as a screening tool for identifying femoral neck osteoporosis. Further primary studies are required to verify the effectiveness of the SI index in identifying populations at risk of osteoporosis.

Evaluating alternatives to dual-energy x-ray absorptiometry for assessing bone quality in patients undergoing spine surgery.

The purpose of this study was to compare and contrast lumbar bone quality and osteoporosis/osteopenia screening results via dual-energy x-ray absorptiometry (DEXA), CT, and MRI. A consecutive series of 426 candidates screened for lumbar disc replacement over a 5-year period beginning in 2018 was reviewed. Patients with a preoperative lumbar spine DEXA scan and a CT and/or MRI scan were included. The primary outcome measures included the bone mineral density (BMD) and osteoporosis or osteopenia classification from DEXA scans, Hounsfield units (HUs) for CT, and vertebral bone quality (VBQ) assessment for MRI. Patients were included if they had a DEXA scan within 1 year of an MRI or CT scan. DEXA BMD scores from composite or level-by-level reports were recorded. Asynchronous MRI and CT measurements were conducted using PACS. Interrater and intrarater reliability scores were generated for both CT and MRI measurements and ranged from 1.000 for MRI L1-4 scans to 0.683 for MRI VBQ. All 3 types of scans were statistically significantly correlated with one another; however, CT was more strongly correlated with the lumbar DEXA value (r = 0.439, p < 0.001). The correlation between MRI VBQ and DEXA was -0.103, (p < 0.045). The CT level-by-level measurements correlate with the corresponding level-by-level DEXA BMD values (correlation ranging from 0.531 to 0.289, p < 0.001 to p = 0.007). CT HU values were more strongly related to osteoporosis/osteopenia classification based on DEXA T-scores than were MRI VBQ values. Receiver operating characteristic analyses found that the area under the curve was 0.817 for CT and 0.539 for MRI. These results demonstrate that CT HUs more closely correlate to DEXA scores than MRI VBQ in this population of patients undergoing surgery for symptomatic disc degeneration. Thus, CT may be an alternative to DEXA for assessing VBQ in this population.

Assessing bone density on MRI: comparison between routine MRI sequences and DEXA scans.

Magnetic Resonance Imaging (MRI) is frequently utilised to aid in the comprehensive assessment of back pain, while dual-energy x-ray absorptiometry (DEXA) is the gold standard test for the assessment of bone density. Assessing bone density on MRI could reduce costs and avoid exposing patients to ionising radiation. The aim of this paper is to investigate whether the relative signal intensity of vertebral bodies compared to other structures can detect osteoporosis on MRI. 100 patients that had undergone both a lumbar spine MRI and a DEXA scan were identified. The T1 and T2 signal intensity of L1-L4 vertebral bodies (VB), cerebro-spinal fluid (CSF), and psoas muscle were measured within a 1-cm2 region of interest (ROI), and the signal intensity ratios were calculated. The ratios were stratified as normal, osteopenic, or osteoporotic based on DEXA T-scores. The T1 VB /T1 CSF ratio was significantly higher in the osteoporotic group than the normal and osteopenic groups (p < 0.001). The T1 VB /T1 CSF ratio had excellent discrimination (AUC = 0.841) for the presence of osteoporosis. The Pearson correlation coefficient between the DEXA T-score and the T1VB/T1CSF ratio was -0.474 (p < 0.001). The intra-observer (ICC = 0.910, 95% CI = 0.757-0.966) and inter-observer reliability (ICC = 0.927, 95% CI = 0.824-0.970) were excellent. In our cohort, a T1 VB / T1 CSF ratio of greater than 4 is 66.7% sensitive but 90.0% specific for the presence of osteoporosis. A high T1VB/T1CSF ratio suggests osteoporosis on MRI. Prospective validation is needed to confirm these findings.

Usefulness of volumetric BMD measurement by using low dose CT image acquired on L-spine Bone SPECT/CT

Purpose: CT scan makes up for the weak point of the nuclear medicine image having a low resolution and also were used for attenuation correction on image reconstruction. Recently, many studies try to make use of CT images additionally, one of them is to measure the bone mineral density(BMD) using Quantitative CT(QCT) software. BMD exams are performed to scan lumbar and femur with DXA(Dual-Energy X-Ray Absorptiometry) in order to diagnose bone disease such as osteopenia, osteoporosis. The purpose of this study is to identify the usefulness of QCT_BMD analyzed with low dose CT images on L-spine Bone SPECT/CT comparing with DXA_BMD. Materials and Methods: Fifty five women over 50 years old (mean 66.4 ± 9.1) who took the both examinations(L-spine Bone SPECT/CT with SIEMENS Intevo 16 and DXA scan with GE Lunar prodigy advance) within 90 days from April 2017 to July 2022, BMD, T-score and disease classification were analyzed. Three-dimensional BMD was analyzed with low dose CT images acquired on L-spine Bone SPECT/CT scan on Mindways QCT PROTM software and two-dimensional BMD was analyzed on DXA scan. Basically, Lumbar 1-4 were analyzed and the patients who has lesion or spine implants on L-spine were excluded for this study. Pearson's correlation analysis was performed in BMD and T-score, chi-square test was performed in disease classification between QCT and DXA. Results: On 55 patients, the minimum of QCT_BMD was 18.10, maximum was 166.50, average was 82.71 ± 31.5 mg/cm3. And the minimum of DXA-BMD was 0.540, maximum was 1.302, average was 0.902 ± 0.201 g/cm2, respectively. The result shows a strong statistical correlation between QCT_BMD and DXA_BMD(p&lt;0.001, r=0.76). The minimum of QCT_T-score was -5.7, maximum was-0.1, average was -3.2 ± 1.3 and the minimum of DXA_T-score was -5.0, maximum was 1.7, average was -2.0 ± 1.3, respectively. The result shows a statistical correlation between QCT T-score and DXA T-score (p&lt;0.001, r=0.66). On the disease classification, normal was 5, osteopenia was 25, osteoporosis was 25 in QCT and normal was 10, osteopenia was 25, osteoporosis was 20 in DXA. There was under-estimation of bone decrease relatively on DXA than QCT, but there was no significant differences statistically by chi-square test between QCT and DXA. Conclusion: Through this study, we could identify that the QCT measurement with low dose CT images QCT from L-Spine Bone SPECT/CT was reliable because of a strong statistical correlation between QCT_BMD and DXA_BMD. Bone SPECT/CT scan can provide three-dimensional information also BMD measurement with CT images. In the future, rather than various exams such as CT, BMD, Bone scan are performed, it will be possible to provide multipurpose information via only SPECT/CT scan. In addition, it will be very helpful clinically in the sense that we can provide a diagnosis of potential osteoporosis, especially in middleaged patients.

Plain radiographic indices are reliable indicators for quantitative bone mineral density in male and female patients before total hip arthroplasty

Osteoporosis is underdiagnosed in patients undergoing total hip arthroplasty (THA). Bone mineral density measurement by dual-energy X-ray absorptiometry (DXA) is the gold standard, but indices on plain hip radiographs also seemed to be reliable screening tools in female or Asian ethnicities in previous studies. Given the lack of knowledge about male patients and Caucasian ethnicities, this study was conducted to evaluate plane hip radiographic indices as a screening tool for osteopenia and osteoporosis in Caucasian female and also male patients before undergoing THA. A retrospective analysis of 216 elderly patients with pre-existing DXA before hip arthroplasty was performed and four indices were calculated on plain hip radiographs: Canal-Flare-Index (CFI), Canal-Calcar-Ratio (CCR), Canal-Bone-Ratio (CBR) 7 and 10 cm below the lesser trochanter. They were correlated with femoral neck DXA T-scores by Pearson’s correlation and intraclass correlation coefficient, and a ROC analysis was performed. A total of 216 patients (49.5% male) were included. CBR-7 and -10 were highly correlated (p < 0.001) with femoral neck T-score in males (Pearson’s correlation CBR-7 r = − 0.60, CBR-10 r = − 0.55) and females (r = − 0.74, r = − 0.77). CBR-7 and -10 also showed good diagnostic accuracy for osteoporosis in the ROC analysis in males (CBR-7: AUC = 0.75, threshold = 0.51; CBR-10: 0.63; 0.50) and females (CBR-7: AUC = 0.87, threshold = 0.55; CBR-10: 0.90; 0.54). Indices such as the Canal Bone Ratio (CBR) 7 or 10 cm below the lesser trochanter on plain hip radiographs are a good screening tool for osteopenia and osteoporosis on plain hip radiographs and can be used to initiate further diagnostics like the gold standard DXA. They differ between male and female patients.

Intraoperative Surgeon Assessment of Bone: Correlation to Bone Mineral Density, CT Hounsfield Units, and Vertebral Bone Quality.

Retrospective observational study of consecutive patients. The purpose of the study is to determine if a surgeon's qualitative assessment of bone intraoperatively correlates with radiologic parameters of bone strength. Preoperative radiologic assessment of bone can include modalities such as computed tomography (CT) Hounsfield units (HUs), dual-energy x-ray absorptiometry (DXA) bone mineral density with trabecular bone score (TBS) and magnetic resonance imaging vertebral bone quality (VBQ). Quantitative analysis of bone with screw insertional torque and pull-out strength measurement has been performed in cadaveric models and has been correlated to these radiologic parameters. However, these quantitative measurements are not routinely available for use in surgery. Surgeons anecdotally judge bone strength, but the fidelity of the intraoperative judgment has not been investigated. All adult patients undergoing instrumented posterior thoracolumbar spine fusion by one of seven surgeons at a single center over a 3-month period were included. Surgeons evaluated the strength of bone based on intraoperative feedback and graded each patient's bone on a 5-point Likert scale. Two independent reviewers measured preoperative CT HUs and magnetic resonance imaging VBQ. Bone mineral density, lowest T-score, and TBS were extracted from DXA within 2 years of surgery. Eighty-nine patients were enrolled and 16, 28, 31, 13, and 1 patients had Likert grade 1 (strongest bone), 2, 3, 4, and 5 (weakest bone), respectively. The surgeon assessment of bone correlated with VBQ (τ=0.15, P =0.07), CT HU (τ=-0.31, P <0.01), lowest DXA T-score (τ=-0.47, P <0.01), and TBS (τ=-0.23, P =0.06). Spine surgeons' qualitative intraoperative assessment of bone correlates with preoperative radiologic parameters, particularly in posterior thoracolumbar surgeries. This information is valuable to surgeons as this supports the idea that decisions based on feel in surgery have a statistical foundation.