AP Lumbar Research Articles

Radiation Dose and Image Quality with Exposure Factor Variation Using a Virtual Grid in Digital Radiography

Digital radiography technology provides many advantages. However, there are still frequent repetitions of inspections due to failure to determine the exposure factor due to a decrease in image quality. Virtual Grid is a digital radiographic image processing technology that converts image quality that is deteriorating due to X-ray scattering to better image quality by reducing the effects of X-ray scattering. Application of a virtual grid can contribute to improving image quality and increasing the procedural efficiency of the workflow in a radiographic examination. This study uses a research-experimental design, with a One-Shot Case Study. The sample selection of 60 samples was carried out randomly by judgmental or purposive sampling. The sampling technique was carried out with specific considerations for the research objectives to determine the optimal exposure factor by using a virtual grid for the skull, lumbar, and pelvic radiographic examinations. Then, it was analyzed quantitatively and qualitatively visually by three radiologists—a bivariate analysis of data using one-way ANOVA. Qualitative analysis was carried out as well as a test. Feel free to assess the agreement of the informants. Results In the quantitative and qualitative analysis, the exposure factor and the ideal virtual grid ratio for optimization are skull AP: 106 kV, 2 mAs, ratio 14:1, skull lateral: 106 kV, 1.25 mAs, ratio 14:1, skull lumbar AP: 106 kV, 4 mAs, ratio 14:1, skull lumbar lateral: 113 kV, 6.3 mAs, 10:1 ratio, and pelvis AP: 92 kV, 8 mAs, 14:1 ratio.

Circulating microRNA responses to acute whole-body vibration and resistance exercise in postmenopausal women

Evaluating alterations in circulating microRNA (c-miRNA) expression may provide deeper insight into the role of exercise in the attenuation of the negative effects of aging on musculoskeletal health. Currently, there are sparse data on c-miRNA responses to acute exercise in postmenopausal women. The purpose of this study was to characterize the effects of acute bouts of resistance exercise and whole-body vibration on expression of selected c-miRNAs in postmenopausal women aged 65-76 years (n=10). We also examined relationships between c-miRNAs and muscle strength and bone characteristics. This randomized crossover design study compared c-miRNA responses to a bout of resistance exercise (RE) (3 sets 10 reps 70% 1 repetition maximum (1RM), 5 exercises) and a bout of whole-body vibration (WBV) (5 sets 1min bouts 20Hz 3.38mm peak to peak displacement, Vibraflex vibration platform). DXA was used to measure body composition and areal bone mineral density (aBMD) of the total body, AP lumbar spine, and dual proximal femur. pQCT was used to measure tibia bone characteristics (4%, 38%, 66% sites). Blood samples were collected before exercise (Pre), immediately-post (IP), 60 minutes post (60P), 24 hours (24H), and 48 hours (48H) after exercise to measure serum miR-21-5p, -23a-3p, -133a-3p, -148a-3p (qPCR) and TRAP5b (ELISA). There was a significant modality × time interaction for c-miR-21-5p expression (p=0.019), which decreased from 60P to 24H after WBV only. TRAP5b serum concentrations significantly increased IP then decreased below Pre at 24H for both WBV and RE (p<0.01). Absolute changes in TRAP5b were negatively correlated with c-miR-21-5p fold changes (r= -0.642 to -0.724, p<0.05) for both exercise modalities. There were significant negative correlations between baseline c-miRNAs and bone status variables (r= -0.639 to -0.877, p<0.05). Our findings suggest that whole-body vibration is a sufficient mechanical stimulus for altering c-miR-21-5p expression, whereas a high intensity resistance exercise protocol did not elicit any c-miRNA responses in postmenopausal women. Increases in the bone resorption marker, TRAP5b, were associated with greater downregulation of c-miR-21-5p expression.

Single-position circumferential lumbar spinal fusion: an overview of terminology, concepts, rationale and the current evidence base.

To provide definitions and a conceptual framework for single position surgery (SPS) applied to circumferential fusion of the lumbar spine. Narrative literature review and experts' opinion. Two major limitations of lateral lumbar interbody fusion (LLIF) have been (a) a perceived need to reposition the patient to the prone position for posterior fixation, and (b) the lack of a robust solution for fusion at the L5/S1 level. Recently, two strategies for performing single-position circumferential lumbar spinal fusion have been described. The combination of anterior lumbar interbody fusion (ALIF) in the lateral decubitus position (LALIF), LLIF and percutaneous pedicle screw fixation (pPSF) in the lateral decubitus position is known as lateral single-position surgery (LSPS). Prone LLIF (PLLIF) involves transpsoas LLIF done in the prone position that is more familiar for surgeons to then implant pedicle screw fixation. This can be referred to as prone single-position surgery (PSPS). In this review, we describe the evolution of and rationale for single-position spinal surgery. Pertinent studies validating LSPS and PSPS are reviewed and future questions regarding the future of these techniques are posed. Lastly, we present an algorithm for single-position surgery that describes the utility of LALIF, LLIF and PLLIF in the treatment of patients requiring AP lumbar fusions. Single position surgery in circumferential fusion of the lumbar spine includes posterior fixation in association with any of the following: lateral position LLIF, prone position LLIF, lateral position ALIF, and their combination (lateral position LLIF+ALIF). Preliminary studies have validated these methods.

The impact of interbody approach and lumbar level on segmental, adjacent, and sagittal alignment in degenerative lumbar pathology: a radiographic analysis six months following surgery

Interbody fusion, including: transforaminal (TLIF), posterior (PLIF), anterior (ALIF), and lateral (LLIF); effectively treat lumbar degenerative pathology and provide spinopelvic balance. Although the decision on surgical approach and technique are multifactorial and patient specific, the impact of the interbody approach on segmental and adjacent level lordosis could be an important factor to consider during pre-operative planning to achieve pre-specified alignment goals. The purpose of this study is to compare the 6-month postoperative radiographic outcomes in the lumbar spine following 1 to 2 level transforaminal (TLIF), posterior (PLIF), anterior (ALIF), and lateral (LLIF) interbody fusions at the L3-4, L4-5, and L5-S1 levels. As our primary outcome, we evaluated the change in segmental lordosis at the level of fusion in ALIF/LLIF approaches compared to TLIF/PLIF. Secondarily, we evaluated the pelvic incidence to lumbar lordosis (PI-LL) mismatch and examined the compensatory lordotic changes at the adjacent levels 6 months following surgery. Retrospective cohort. This retrospective study included 18 centers of various practice settings across the United States. Patients were included in the study if they underwent a one- or two-level primary lumbar fusion for degenerative pathology. Measurements of the pre-operative and 6-month post-operative lumbar AP and lateral lumbar plain radiographs included: pelvic incidence (PI), pelvic tilt, lumbar lordosis from L1-S1 (LL), as well as segmental lordosis (SL) of each segment between L1-S1. Due to there being 2 evaluated time points, patients were then grouped based on alignment into categories of preserved, restored, not corrected, and worsened. 474 patients underwent 608 levels of fusion. ALIF/LLIF resulted in significantly more segmental lordosis compared to TLIF/PLIF procedures at both L4-5 and L5-S1 (p<.001). Overall, ALIF/LLIF resulted in significantly more global lumbar lordotic alignment change compared to TLIF/PLIF (p=.01). Whether patients' alignment was preserved versus worsened was not significantly predicted by type of procedure. Similarly, whether patients' alignment was restored versus not corrected was not significantly predicted by type of procedure. Finally, anterior approaches resulted in decreased lordosis at adjacent levels, thus resulting in a more neutral position. In this large multicenter retrospective study of 1 to 2 level interbody fusion surgeries, we identified that A/LLIF procedures at L4-L5 and L5-S1 resulted in greater segmental lordosis restoration and PI-LL mismatch improvement compared to T/PLIF procedures. A/LLIF may also significantly reduce lordosis (compared to T/PLIF) at the adjacent levels in a fashion that serves to reduce the lumbar lordosis that may have been increased at the fused level.

Opportunistic use of dual-energy X-ray absorptiometry to evaluate lumbar scoliosis.

Osteoporosis and scoliosis are interrelated disease processes. Dual-energy X-ray absorptiometry (DXA), used to assess bone density, can also be used to evaluate spinal deformity since it captures a posteroanterior (PA) image of the lumbar spine. We assessed the use of DXA to evaluate lumbar spine alignment. A lumbar spine DXA phantom was used to assess the effects of axial and sagittal plane rotation on lumbar bone mineral content (BMC), density (BMD), and L1-L4 Cobb angle measurements. Using two subject cohorts, intra- and inter-observer reliability and validity of using DXA for L1-L4 Cobb angle measurements in the coronal and sagittal planes were assessed. Axial and sagittal plane rotation greater than 15° and 10°, respectively, significantly reduced measured BMD and BMC; there was minimal effect on Cobb angle measurement reliability. In human subjects, excellent intra- and inter-observer reliability was observed using lumbar PA DXA images for Cobb angle measurements. Agreement between Cobb angles derived from lumbar PA DXA images and AP lumbar radiographs ranged from good to excellent. The mean difference in Cobb angles between supine lumbar PA DXA images and upright AP lumbar radiographs was 2.8° in all subjects and 5.8° in those with scoliosis. Lumbar spine rotation does not significantly affect BMD and BMC within 15° and 10° of axial and sagittal plane rotation, respectively, and minimally affects Cobb angle measurement. Spine alignment in the coronal plane can be reliably assessed using lumbar PA DXA images.

Effect of diet and lifestyle on the bone mineral density of postmenopausal women of Mumbai

Osteoporosis is a common public health problem affecting one in four women or one in eight men older than 50 years. The aim of the study was to categorize the percentage of women who are having normal BMD, osteoporosis and osteoporotic and to evaluate the relation between anthropometric profile, calcium intake (dietary and supplemental) and life style pattern with BMD. An observational study of 50 post-menopausal women was carried out using an interview schedule to collect information regarding diet, lifestyle and anthropometry. DEXA scan reports of the AP Lumbar spine (L1-L2), femoral neck left and femoral neck right sites were used to assess bone health. ANOVA and Pearson chi-square test were used and correlation was considered statistically significant at p < 0>.The percentage of women with normal BMD, osteopenia and osteoporosis were 39.6%, 49.6% and 10.8% respectively. Higher percentage of Women with low BMI were osteoporotic. There was a significant positive correlation between BMD and frequency of intake of calcium rich foods (green gram dal, ragi, coconut dry, gingelly seed and milk) and a negative correlation of BMD with coffee intake. There was a positive correlation between the intake of calcium supplement and BMD of femoral neck left. In the present study it was observed that intake of calcium rich food and calcium supplement can have a positive effect on BMD of post-menopausal women. On the other hand lower BMI and coffee intake may have negative effects on BMD. Thus, dietary and life style patterns of post- menopausal women may significantly influence BMD. Keywords: Post menopause, BMD (Bone mineral density), osteoporosis, osteopenia, DEXA Scan.

The Effect Of Age On The Lumbar Spine Of Cricket Fast Bowlers

Senior cricket fast bowlers (FB) have high lumbar spine bone mineral, particularly on the contralateral side to their bowling arm. It is thought that bone possesses its greatest ability to adapt to loading during adolescence but is unknown at what age asymmetry develops in FB and how adaptation develops with age. PURPOSE: To determine how lumbar bone mineral and geometrical properties differ according to age in FB. METHODS: With NHS and institutional ethics approval, 107 elite adolescent and senior male FB aged 14 to 35 years received a single AP lumbar spine DXA scan (GE Lunar iDXA, GE Healthcare, USA). Bone mineral density (BMD) and bone mineral content (BMC) were derived for each vertebra, along with average vertebral height and width, area and Z-score (Lunar enCore v17, GE Healthcare, USA). Custom regions of interest derived the bone mineral in the lateral third of the non-dominant (ND) and dominant (D) sides of the vertebral body (respective to bowling arm). FB were split into 14-15 (n=27), 16-17 (n=28), 18-19 (n=22), 20-24 (n=16), and 25+ (n=14) age groups. ANOVAs were used to compare the age group means for each variable, with FFM as covariate. RESULTS: Lumbar spine BMD, BMC, Z-score, area, width and height significantly differed between age groups at all vertebral levels (P<0.01), but differences in area and height were no longer significant with FFM included as a covariate (P≥0.38). Mean BMD (± SD) L1-L4 Z-scores increased progressively with age from +0.83 ± 1.24 at age 14-15 to +2.69 ± 1.17 at age 25+. BMD and BMC on the ND and D sides significantly differed with age (P≤0.04) and side (P<0.01), and by age on each side (P≤0.04) as highlighted at L3 in figure 1. CONCLUSIONS: Adaptation to fast bowling, in terms of whole vertebra and site-specific bone mineral, substantially increases with age particularly on the ND side.

Analysis of hidden blood loss and its risk factors in the treatment of osteoporotic vertebral compression fractures with PVP

To investigate the influencing factors of hidden blood loss (HBL) during the treatment of percutaneous vertebroplasty (PVP). The clinical data of 125 patients with osteoporotic vertebral compression fractures (OVCFs) treated with percutaneous vertebroplasty from March 2016 to December 2017 were retrospectively analyzed. All patients underwent X rays of the AP and lateral lumbar spine, double oblique, and dynamic positions. Lumbar spine CT, MRI, and dual energy X ray bone densitometer (DXA) were used to confirm the diagnosis. There were 55 males and 70 females, 10 cases of thoracic vertebrae, 89 cases of thoracolumbar vertebrae, 26 cases of lumbar vertebrae, 87 cases with single segment, 29 cases with double segment,and 9 cases with 3 segments. The vertebral compression height ratios of 67 patients were less than 1 / 3, and the ratios for 41 patients were from 1 / 3 to 2 / 3,for 17 patients were more than 2 / 3. Blood routine examination were performed before and 3 days after surgery to analyze hidden blood loss and to explore its risk factors. The average hidden blood loss was (317±156) ml in 125 patients. Multiple linear regression analysis revealed a history of diabetes(P=0.011),surgical segments(P=0.036),number of segments (P<0.001),vertebral height loss rate (P=0.002),vertebral height recovery rate (P<0.001) and bone cement leakage rate (P=0.003) were positively correlated with hidden blood loss. Moreover,it was found that the blood loss was higher in those with higher vertebral height loss rate than in those with lower vertebral height loss rate, and the blood loss was higher in those with good vertebral height recovery than those with poor vertebral height recovery. Additionally,the cement leakage was also an important factor in increasing hidden blood loss. However,there was no significant correlation between bone mineral density(P=0.814) or history of hypertension(P=0.055) and hidden blood loss. Patients with OVCFs have a large amount of hidden blood loss after PVP treatment, which needs attention. At the same time, the history of diabetes, surgical segments, number of segments, bone cement leakage rate, vertebral height loss rate and vertebral height recovery rate are the risk factors for hidden blood loss.

A pilot study investigating two dose reduction techniques for AP lumbar spine radiography using direct dosimetry and Projection VR

IntroductionThe purpose of this study was to compare radiation dose measurements generated using a virtual radiography simulation with experimental dosimeter measurements for two radiation dose reduction techniques in digital radiography. MethodsEntrance Surface Dose (ESD) measurements were generated for an antero-posterior lumbar spine radiograph experimentally using NanoDOT™, single point dosimeters, for two radiographic systems (systems 1 and 2) and using Projection VR™, a virtual radiography simulation (system 3). Two dose reduction methods were tested, application of the 15% kVp rule, or simplified 10 kVp rule, and the exposure maintenance formula. The 15% or 10 kVp rules use a specified increase in kVp and halving of the mAs to reduce patient ESD. The exposure maintenance formula uses the increase in source-to-object distance to reduce ESD. ResultsIncreasing kVp from 75 to 96 kVp, with the concomitant decrease in mAs, resulted in percent ESD reduction of 59.5% (4.02–1.63 mGy), 60.8% (3.55–1.39 mGy), and 60.3% (6.65–2.64 mGy), for experimental systems 1 and 2, and virtual simulation (system 3), respectively. Increasing the SID (with the appropriate increase in mAs) from 100 to 140 cm reduced ESD by 22.3% 18.8%, and 23.5%, for experimental systems 1 and 2, and virtual simulation (system 3), respectively. ConclusionPercent dose reduction measurements were similar between the experimental and virtual measurement systems investigated. For the dose reduction practices tested, Projection VR™ provides a realistic alternate of percent dose reduction to direct dosimetry.

The Relationship Between A Bone-specific Physical Activity Score, Body Composition, And Bone Mineral Density In Korean College Females

PURPOSE: The purpose of this study was to investigate the relationship between a bone-specific physical activity (BPAQ) score, body composition, and bone mineral density (BMD) in Korean college females. METHODS: Seventy three college females (21.7 ± 1.8 years; 162.1 ± 4.6 cm; 53.9 ± 5.8 kg) between the ages of 19 and 26 years were recruited from the Universities in Seoul and Gyeonggi areas, South Korea. We used Dual Energy X-ray to measure the BMD of AP lumbar spine (L2-L4) and proximal femur (non-dominant side; total hip, femoral neck, trochanter). We used X-scan plus II (Hospital body Composition Analyzer, Jawon Medical Korea) to measure height (cm), weight (kg), fat free mass (kg), percent body fat (%), and body mass index (BMI). Participants were asked to record 24-hour food intake recall questionnaire. We analyzed total caloric intake (kcal), protein (g), carbohydrate (g), fat (g), vitamin D (μg), calcium (mg), and magnesium (mg) using the Computer Aided Nutritional analysis program (CAN-Pro 4.0). The BPAQ current (previous 12 months) and past (from one year of age) scores were used to obtain a comprehensive account of lifetime physical activity. RESULTS: Weight (p<0.01), BMI (p<0.05), and fat free mass (p<0.001) were positively related to the BMD of L2-L4. Also, weight (p<0.05) and BMI (p<0.05) were positively related to the BMD of femoral neck. Pearson’s correlation showed a positive relationship between vitamin D and spine L2-L4, but there were no linear relationships between other dietary intake variables (p>0.05). There were no significant correlations between BMD variables and BPAQ scores (p>0.05). When fat free mass, BPAQ past score, and vitamin D were included in a multiple linear regression analysis, fat free mass and BPAQ past score were the only remaining predictors of L2-L4 BMD and femoral neck BMD, accounting for 26.4% and 11.8%, respectively. CONCLUSION: It is recommended that healthy body composition and active lifestyle are important to maintain bone health in college females. This work was supported by the National Research Foundation of Korea Grant funded by the Korean Government (NRF-2013S1A5B5A07046267)

The Choice of Lower Instrumented Vertebra in AIS Comparison of Lenke, Suk and Dubousset Criteria

Background Distal extension of the selective fusion in AIS is currently among the most explored topics in literature especially for Lenke type 1 and 2 curves and a lot of variability in the distal extension of the fusion is noted among different specialized centers around the world. Methods This is a retrospective descriptive study examining 41 Adolescent Idiopathic Scoliosis (AIS) cases (Lenke type I or II curves) undergoing posterior selective fusion with a minimum follow up of 2 years. We assessed the concordance between Dubousset's, Lenke's and Suk's criteria in the choice of the Lower Instrumented Vertebra (LIV). Baseline and post-operative X-rays of 41 AIS patients presenting with Lenke type I or II curves treated with selective fusion were studied. For each patient, the LIV is determined according to Dubousset's, Suk's and Lenke's criteria. Based on these results, patients are divided into two groups. “Group 1” includes patients where LIV designated by Dubousset's criteria is identical to the LIV designated by Lenke's or Suk's criteria. “Group 2” includes patients where the LIV dictated by Dubousset's criteria is more distal when compared with the LIV dictated by Lenke's and Suk's criteria. The charts of those 41 patients are reviewed at their last post-operative follow-up. The primary outcome measure used to compare those different groups is the frontal balance. The secondary endpoints are the (1) AP Cobb angle of the thoracic curve, (2) the AP Cobb angle of the lumbar curve, (3) the improvement of the Cobb angle of the thoracic curve (% ACT), (4) the improvement of the Cobb angle of the lumbar curve (% ACL), (5) the AP and lateral inclination of the LIV, (6) the AP lumbar Apical Vertebral Translation (AVT-L) and (7) the lateral Cobb angle of D5-D12. Results The LIV recommended by Lenke and the one recommended by Suk's criteria are identical in 70% of cases. The match between the choice based on Dubousset's criteria and the choice accounted by Lenke's or Suk's criteria is obtained for 70% of patients also. In 20% of cases, the LIV recommended by Dubousset's criteria is more distal than the one recommended by Lenke and Suk. Groups' comparison. Preoperatively, the comparison between groups 1 and 2 for the frontal balance and for the secondary endpoints shows no difference. Similarly, non-statistically significant difference was found between both groups for the primary and the secondary endpoints in the immediate post-operative setting and on the last follow-up. Conclusions The 70% accordance rate between Dubousset's criteria and those of Lenke and Suk attributes some validity to Dubousset's criteria. Thus, the statistical study showing no evolution toward a postoperative coronal imbalance or toward a worsening of other structural criteria of the spine curvatures in group 2, which is discordant with the recommendations of Lenke and Suk, prove the validity of the selection criteria of the LIV according to Dubousset. These same results also show that a more extensive distal correction-fusion does nothing for the frontal balance in the immediate postoperative setting, and even after several months of follow-up.

Radiation dose measurement for patients undergoing common spine medical x-ray examinations and proposed local diagnostic reference levels

The main purposes of this study were to investigate patient dose in Spine radiographic examinations, as high dose procedures and propose the first LDRLs (Local Diagnostic Reference Levels) in Khuzestan region, southwest of Iran. ESD (Entrance Skin Dose) values of patients who underwent six spine radiographic procedures containing cervical (AP/LAT), thoracic (AP/LAT) and lumbar (AP/LAT), as high dose procedures, were evaluated. Patient doses were calculated from patient's individual anatomical data (weight, height and organ thickness) and exposure parameters (kVp, mAs, FFD and projection) based on the IAEA (International Atomic Energy Agency) Technical Report Series No.457. Indirect dosimetry method was conducted on 412 standard patients (57% men and 43% women) at seven high-patient-load hospitals. This survey reveals significant variations in the radiological practice. Despite large discrepancies found in the tube loadings (3–128 for lumbar AP and 3–200 for lumbar LAT), ESDs in all examinations were lower than the IAEA and EC (European Commission) DRLs (Diagnostic Reference Levels), 1.30, 1.65, 2.29, 3.09, 5, 7.5 mGy for cervical AP, cervical LAT, thoracic AP, lumbar AP, thoracic LAT and lumbar LAT respectively. Optimization of radiological practice could be accelerated by updating clinical audits and patient dose considerations, adequate training of students, implementation of systematic QA and QC programs and the use of qualified diagnostic medical physicists in the imaging sections. It is advisable that DRLs obtained in this study can be used as local DRL and dose surveys must be performed in all regions to establish NDRLs (National Diagnostic Reference Levels) in Iran. Also, national authorities must review periodically reference levels to ensure that it remains appropriate.

Decision Making and Variation in Radiation Exposure Factor Selection by Radiologic Technologists

The goal of radiographic imaging is to produce a diagnostically useful image while minimizing patient radiation dose. This study aimed to review variations in exposure factor selection by radiologic technologists for virtual patients with varying body mass index characteristics. Eleven technologists were asked to assign exposure parameters (kVp, mAs, source-to-image receptor distance, and grid use) to 10 computer-generated patient images for each of four radiographic examinations (anteroposterior [AP] shoulder; AP lumbar spine; lateral lumbar spine; AP portable chest). The virtual patients represented five body mass index categories–underweight, healthy weight, overweight, obese, and superobese. As participants assigned exposures, their visual patterns were recorded by a Tobii TX300 eye-tracker. Significant (P < .05) correlation was found between radiographer age/experience and assignment of mAs for AP shoulder and lumbar examinations. Greater age/experience correlated with higher mAs for the AP shoulder examination, but with lower values for lumbar examinations. Strong correlations also existed between times to first fixations on relevant anatomic areas, and kVp/mAs values existed for the AP portable chest examination. Exposure selection differences related to age/experience highlight inconsistencies in the practice of exposure parameter setting. The reason for these inconsistencies requires further investigation, and how to address deficiencies in practice requires consideration to optimize safe patient care. Because of the small sample size used, further research into the relationship between visual factors and individual examinations is suggested, after the findings regarding the AP portable chest examination.

Post-operative Radiographs for Degenerative Lumbar Spinal Fusions?

A retrospective review of 70 consecutive lumbar degenerative surgical cases in which intraoperative fluoroscopic imaging was compared with immediate postoperative radiographs using a novel vertebral grid-coordinate system. Same-hospitalization postoperative standing lumbar AP and lateral radiographs do not appear to be cost-effective or to provide additional clinically relevant information when intraoperative fluoroscopy is utilized.

Moving back: The radiation dose received from lumbar spine quantitative fluoroscopy compared to lumbar spine radiographs with suggestions for dose reduction

PurposeQuantitative fluoroscopy is an emerging technology for assessing continuous inter-vertebral motion in the lumbar spine, but information on radiation dose is not yet available. The purposes of this study were to compare the radiation dose from quantitative fluoroscopy of the lumbar spine with lumbar spine radiographs, and identify opportunities for dose reduction in quantitative fluoroscopy. MethodsInternationally reported dose area product (DAP) and effective dose data for lumbar spine radiographs were compared with the same for quantitative fluoroscopy and with data from a local hospital for functional radiographs (weight bearing AP, lateral, and/or flexion and extension) (n = 27). The effects of procedure time, age, weight, height and body mass index on the fluoroscopy dose were determined by multiple linear regression using SPSS v19 software (IBM Corp., Armonck, NY, USA). Results and conclusionThe effective dose (and therefore the estimated risk) for quantitative fluoroscopy is 0.561 mSv which is lower than in most published data for lumbar spine radiography.The dose area product (DAP) for sagittal (flexion + extension) quantitative fluoroscopy is 3.94 Gy cm2 which is lower than local data for two view (flexion and extension) functional radiographs (4.25 Gy cm2), and combined coronal and sagittal dose from quantitative fluoroscopy (6.13 Gy cm2) is lower than for four view functional radiography (7.34 Gy cm2).Conversely DAP for coronal and sagittal quantitative fluoroscopy combined (6.13 Gy cm2) is higher than that published for both lumbar AP or lateral radiographs, with the exception of Nordic countries combined data.Weight, procedure time and age were independently positively associated with total dose, and height (after adjusting for weight) was negatively associated, thus as height increased, the DAP decreased.

FRI0259 Increased risk of osteoporosis and fracture in women with systemic sclerosis: A comparative study to rheumatoid arthritis and healthy controls

ObjectivesTo investigate whether women with SSc have increased risk of OP and fractures compared to a “high risk” population with rheumatoid arthritis (RA) and also healthy controls.MethodsCross-sectional study with successive...

Comparison of mandibular bone mineral density in osteoporotic, osteopenic and normal elderly edentulous subjects measured by the dual‐energy X‐ray absorptiometry technique

The aim of this study was to compare the mandibular body bone mineral density according to bone mineral density status of spine and femur measured by dual-energy X-ray absorptiometry (DXA) technique in elderly edentulous individuals. One of the factors that affect the survival rate of implants is bone mineral density (BMD) of the jaws. Fifty edentulous elderly patients' (27 women and 23 men) spine, femur and the mandibular body BMDs were measured using DXA technique. BMD scans of the AP lumbar spine (L2-L3) and femur were classified using World Health Organisation criteria for bone mass. There was a statistically significant difference between the normal femur group's-osteoporosis group's mandibular body BMD (p = 0.001) and femoral osteopaenia group's-osteoporosis group's mandibular body BMD (p < 0.001). The femoral osteoporosis group's mandibular body BMDs were lower than those of both the normal femoral and the femoral osteopaenia group subjects'. Classification of edentulous mandibles according to low and high bone mineral densities is a problem in implant dentistry. The results of this study demonstrated that femoral bone mineral density status may be used to provide preliminary information about the bone mineral density of the mandibular body region in elderly edentulous subjects.

SU‐E‐I‐79: Patient Doses Reduction in Simple Radiographic Examinations in Busy Radiology Departments

Purpose: To reduce entrance surface air Kerma (ESAK) of routine radiological examinations in some heavy loaded radiology departments using proper equipments and training.Methods: ESAK for 12 routine radiographic examinations has been measured in 10 high loaded radiology departments belonging to country main health insurance organization after quality control for x_ray units and proper training for all radiographers of each departments to use proper technical charts for each room, mainly according to EUR 16260 and optimized exposure factors. The ESAK were measured according to X‐ray tube output, optimized exposure parameters including tube potential(kVp), tube current (mA), focus to skin distance (FSD) for each technique. Results: .The mean reduced ESAK values after optimization of exposure parameters for abdomen, AP and lateral cervical spine, PA and lateral chest, AP and lateral lumbar spine, pelvis, PA and lateral skull, AP and lateral thoracic spine 4.61, 1.19,1.20, 0.26, 0.59 4.63, 6.56, 4.23, 2.90, 2.55, 3.89 and 4.94 mGy, respectively. There were very significant reduction in ESAK by a factor of 36% for abdomen,28% and 35% for AP and lateral cervical spine,62% and 60% for PA and lateral chest, 41% and 53% for AP and lateral lumbar spine, 35% for pelvis, 27% and 22% for AP and lateral skull, 47% and 53% for AP and lateral thoracic spine. Mean, median, first and third quartile of values of ESAK are reported. Conclusion: Significant dose reduction was achieved with proper and simple training and without considerable change in repeat and reject analysis. This reasonable outcome will lead us to establish optimized National Diagnostic Reference Levels (NDRLs).

Identification of the L4-5 interspinous space using difference in heights of two consecutive spinous processes.

The appropriate landmark of spinal puncture is important for preventing spinal cord injury. L4 spinous process (SP) is the largest in size and L5 is the smallest. In this study 'height of SP' is the longitudinal length of SP on lumbar AP view. The purpose of this study was to identify the L4-5 interspinous space (ISS) using difference between L4, 5 SP heights. Sixty-six patients scheduled for spine surgery were enrolled. After induction of general anesthesia, patients were changed to a prone position. The lumbar vertebrae were palpated from the lowest point of the lumbar spine and cranially. We palpated the difference in spinous process heights and marked the point of step-off from L4 SP to L5 SP. The level was radiologically confirmed. Direction of estimation error and the effects of spondylolisthesis, sex, and obesity were also analyzed. The number of accurate identification of the L4-5 ISS in males was 36 (85.7%), in females was 17 (70.8%), and in total 53 (80.3%). The difference between L4 and L5 SP heights (DL4-5SPHs) and sex affect the results. DL4-5SPHs were larger in concordant patients than in discordant patients (7.2 +/- 4.9 mm: 5.0 +/- 1.6 mm, P < 0.05). Among errors, there were more cephalad identified cases compared to caudad identified ones (12.1%: 7.6%). The identification of L4-5 ISS using SP height difference was considerably accurate. So, we considered this might be a useful method for spinal anesthesia.

Definition of a population‐specific dual energy X‐ray absorptiometry reference standard in Isfahani women

AbstractObjective: There are some clues that correct interpretation of bone mineral density (BMD) when measured by dual‐energy X‐ray absorptiometry (DXA) which requires a population specific reference range. We determined reference values of BMD and the prevalence of osteopenia and osteoporosis in postmenopausal Isfahani women.Methods: In this cross‐sectional study, 1118 healthy women from Isfahan, aged between 20 and 80 years were recruited door‐to‐door for research. BMD was measured at the anteroposterior lumbar spine (L2–L4) (AP) and femoral neck (FN) with the Lunar DPX‐IQ densitometer. Peak bone mass (PBM), reference curves of BMD, prevalence of osteoporosis and osteopenia were determined according to World Health Organization (WHO) criteria.Results: In Isfahani women osteoporosis and osteopenia of the AP lumbar spine exists at BMD &lt; 0.898 g/cm2 and between 1.078 g/cm2 and 0.898 g/cm2, respectively. At the FN a BMD &lt; 0.676 g/cm2 defines osteoporosis whereas osteopenia is defined as a BMD between 0.841 g/cm2 and 0.676 g/cm2. The prevalence of osteoporosis and osteopenia at the AP lumbar spine in the age groups 51–55, 56–60, 61–65, 66–70, &gt; 70 years were, 7.9%, 19.6%, 26%, 32.1%, 31.8%, and 28.9%, 36.5%, 38.4%, 41.1%, 45.5%, respectively. The prevalence of osteoporosis and osteopenia at the FN in the same age groups, were, 2.6%, 2%, 12.3%, 14.3%, 22.7% and 28.3%, 39.9%, 43.8%, 50%, 68.2%, respectively.Conclusions: Our data would use a population‐specific reference range for DXA measurements and to estimate the prevalence of osteopenia and osteoporosis.