Diagnostic Reference Values Research Articles

Sex-specific associations between serum uric acid levels and risk of hypertension for different diagnostic reference values of high blood pressure.

The association between uric acid (UA) and hyperuricemia with 5-year hypertension incidence using different blood pressure (BP) diagnostic references in men and women without cardiometabolic diseases is unknown. We used the checkup data from Kagoshima Kouseiren Hospital. All participants with hypertension or on BP medication, diabetes, dyslipidemia, obesity, estimated glomerular filtration rate<60 ml/min/1.73m2, metabolic syndrome, history of gout, and UA-lowering medication were excluded. UA was categorized into sex-specific quartiles and hyperuricemia was defined as UA > 7 mg/dl in men and UA > 6 mg/dl in women. We performed multivariate logistic regression to assess the effects of UA on hypertension development. The 5-year hypertension incidence was defined as subsets of BP ≥ 140/90 mmHg in cohort 1 and BP ≥ 130/80 mmHg in cohort 2. The study enrolled 21,443 participants (39.8%, men) in cohort 1 and 15,245 participants (36.5%, men) in cohort 2. The incidence of hypertension in cohorts 1 and 2 over 5 years was 16.3% and 29.7% in men and 10.9% and 21.4% in women, respectively. When comparing the fourth to the first UA quartile, there was an association with hypertension in men in cohort 1, with odds ratio (OR): 1.36 (95% confidence interval [CI], 1.13-1.63, p < 0.01) and cohort 2, OR: 1.31 (95%CI, 1.09-1.57, p < 0.01), respectively, but not in women. Additionally, an association between hyperuricemia and hypertension was observed in men only in cohort 1, with OR: 1.23 (95%CI, 1.07-1.42, p = 0.02), and in women in cohort 2, OR: 1.57 (95%CI, 1.14-2.16, p < 0.01). The effect of UA on the development of hypertension is influenced by sex and incidence differs with the BP reference used. Uric acid effect on the development of hypertension is affected by sex and incidence differs with the BP reference used.

Entrance surface air kerma to patients during digital radiographic examinations in Tanzania.

The aim of this study was to determine the entrance surface air kerma (ESAK) in adult patients during digital radiography and to evaluate the optimisation potential in five common X-ray examinations in Tanzania. Based on a sample of 240-610 patients, ESAK was estimated using X-ray tube output measurements, patient information and backscatter factors. The results show that the mean ESAK values were higher or comparable to data from the literature. The diagnostic reference values of ESAK for digital radiography were 0.31 mGy (chest PA), 4 mGy (lumbar spine AP), 5.4 mGy (lumbar spine LAT), 3.8 mGy (abdomen AP) and 2.4 mGy (pelvis AP). For computed radiography, the mean ESAK ranges were 0.44-0.57 mGy (thoracic AP), 3.59-3.72 mGy (lumbar spine AP), 6.16-6.35 mGy (lumbar spine LAT), 3.89-3.44 mGy (abdominal AP) and 2.92-3.47 mGy (pelvic AP). In conclusion, high ESAK variations show the potential for optimising protection in digital radiology.

Accuracy, Hemorrhagic Complications and CT Radiation Dose of Emergency External Ventricular Drain (EVD) Placement in Pediatric Patients: A 15-Year Retrospective Analysis.

To assess accuracy, the frequency of hemorrhagic complications and computed tomography (CT) radiation dose parameters in pediatric patients undergoing landmark-guided external ventricular drain (EVD) placement in an emergency setting. Retrospective analysis comprised 36 EVD placements with subsequent CT control scans in 29 patients (aged 0 to 17 years) in our university hospital from 2008 to 2022. The position of the EVD as well as the presence and extension of bleeding were classified according to previously established grading schemes. Dose length product (DLP), volume-weighted CT dose index (CTDIvol) and scan length were extracted from the radiation dose reports and compared to the diagnostic reference values (DRLs) issued by the German Federal Office for Radiation Protection. After the initial EVD placement, optimal positioning of the catheter tip into the ipsilateral frontal horn or third ventricle (Grade I), or a functional positioning in the contralateral lateral ventricle or the non-eloquent cortex (Grade II), was achieved in 28 and 8 cases, respectively. In 32 of 36 procedures, no evidence of hemorrhage was present in the control CT scan. Grade 1 (<1 mL) and Grade 2 (≥1 to 15 mL) bleedings were detected after 3 and 1 placement(s), respectively. For control scans after EVD placements, CTDIvol (median [25%; 75% quartile]) was 39.92 [30.80; 45.55] mGy, DLP yielded 475.50 [375.00; 624.75] mGy*cm and the scan length result was 136 [120; 166] mm. Exceedances of the DRL values were observed in 14.5% for CTDIvol, 12.7% for DLP and 65.6% for the scan length. None of these values was in the range requiring a report to the national authorities. Landmark-based emergency EVD placement in pediatric patients yielded an optimal position in most cases already after the initial insertion. Complications in terms of secondary hemorrhages are rare. CT dose levels associated with the intervention are below the reportable threshold of the national DRLs in Germany.

Ocular examination findings and selected ophthalmic diagnostic tests in African green monkeys (Chlorocebus aethiops sabaeus).

To document ocular lesions and establish ophthalmic diagnostic test reference values in a colony of African green monkeys (Chlorocebus aethiops sabaeus). Fifty one geriatric (GAGM, 19-30 years old), 10 adult (AAGM, 5-9 years old) and 10 juvenile (JAGM, <2 years old) African green monkeys housed in a single Caribbean research colony. Ocular biomicroscopy, indirect fundoscopy, Schirmer tear test (STT), rebound tonometry (TonoVet®) and corneal fluorescein staining were performed. Mixed ANCOVA tests were performed to compare STT and IOP between groups. Common ocular lesions in GAGM included vitreal degeneration (27/51, 51/102 eyes) and cataracts (21/51, 32/102 eyes). Vitreal degeneration was also common in AAGM (8/10, 16/20 eyes) and infrequent in JAGM (3/10, 6/20 eyes). Cataracts were not present in any JAGM or AAGM. All eyes in all three groups had perilimbal corneal pigmentation and faint lace-like anterior corneal stromal opacification. Median (range) STT values were 16.0 (18) mm/min in GAGM. Mean (SD) STT values were 14.2 (4.6) mm/min in AAGM, and 8.9 (3.4) mm/min in JAGM. Median (range) IOP values were 16.5 (27) mmHg in GAGM. Mean (SD) IOP values were 18.0 (2.8) mmHg in AAGM, and 14.1 (2.2) mmHg in JAGM. JAGM had significantly lower STT and IOP values compared to AAGM (p = .0449, .0057, respectively) and GAGM (p = .0002, .0130, respectively). Spontaneous ocular lesions were common in geriatric monkeys in this research colony. IOP and STT values were lower in juvenile African green monkeys relative to adult or geriatric animals.

PS-BPP02-4: DIFFERENCES IN RISK FACTORS FOR DEVELOPING HYPERTENSION WHEN HYPERTENSION REFERENCE VALUES ARE CHANGED

Objective: In 2017, the American College of Cardiology (ACC) and the American Heart Association (AHA) lowered the diagnostic reference value for hypertension to 130/80 mmHg. On the other hand, the Japan Society of Hypertension (JSH) Guidelines for the Treatment of Hypertension 2019 set the diagnostic reference value at 140/90 mmHg because there is insufficient evidence to set it at 130/80 mmHg in Japan. We sought to determine whether there were differences in risk factors predicting future development of hypertension if the diagnostic threshold were lowered in Japan. Method: Of 137,308 subjects who underwent health checkup between 2007 and 2015, 18,657 middle-aged men who were observable for 5 years were included in the study. First, we adapted the JSH2019 criteria and used nominal logistic regression analysis to explore factors involved in the development of hypertension in normotensive subjects who are judged to be normotensive at the first checkup and hypertensive 5 years later. Age, systolic blood pressure, diastolic blood pressure, BMI, uric acid, LDL, HDL, triglycerides, HbA1c (JDS), eGFR, smoking history, daily drinking habit were used as factors for adjustment. Next, the ACC/AHA2017 criteria were adapted and analyzed using the same method to examine the differences in relevant factors from the adaptation of the JSH2019. Results: 12,296 subjects were considered normotensive at first checkup according to JSH2019 criteria. After 5 years, 2,568(20.8%) were diagnosed with hypertension. Age [OR = 1.04, CI = 1.03–1.05, p &lt; 0.001], BMI [OR = 1.08, CI = 1.03–1.13, p &lt; 0.001], uric acid [OR = 1.11, CI = 1.06–1.16, p &lt; 0.001], HbA1c(JDS) [OR = 1.19, CI = 1.10–1.28, p &lt; 0.001], and daily drinking habit [OR = 0.75, CI = 0.66–0.86, p &lt; 0.001] were associated with development of hypertension at 5 years. On the other hands, 7,892 subjects were considered normotensive at first checkup when AHA/ACC2017 criteria were adapted. After 5 years, 5.549(45.1%) were diagnosed with hypertension. Age [OR = 1.03, CI = 1.01–1.04, p &lt; 0.001], BMI [OR = 1.08, CI = 1.02–1.14, p = 0.006], uric acid [OR = 1.15, CI = 1.08–1.21, p &lt; 0.001] and daily drinking habit [OR = 0.69, CI = 0.60–0.80, p &lt; 0.001] were associated with development of hypertension at 5 years. Conclusions: Adapting the AHA/ACC2017 criteria will result in more people developing hypertension than the JSH2019 criteria. Aging, elevated uric acid, and daily drinking habits are risk factors that predict future hypertension, even according to the AHA/ACC2017 criteria.

Radiation protection during fluoroscopic interventions

Facts and figures about the frequencies of fluoroscopically guided interventions (FGI), typical patient exposures and occupational exposures are listed. Limits of radiation exposure do not exist for patients but only for occupationally exposed medical personnel. Measures for radiation protection of patients and personnel are explained. Nearly all technical radiation protection measures for patients also protect the personnel. To reduce the exposure of medical personnel, radiation protection equipment should be attached to the X‑ray modality and personal radiation protection equipment should be worn. The diagnostic reference values and the obligation to report incidents, including the reporting criteria, are explained. The radiation protection of patients and personnel for FGI in Germany is well regulated by diagnostic reference values, reporting criteria, prescribed or recommended protective measures, personal dosimetry and the obligation to involve medical physics experts.

Diagnostic reference value of antibody levels measured using enzyme immunoassay for subacute sclerosing panencephalitis.

High measles-specific antibody titers in the cerebrospinal fluid (CSF) have important diagnostic significance for subacute sclerosing panencephalitis (SSPE), a progressive neurological disorder caused by measles virus variants. However, the diagnostic reference value of antibody levels and the usefulness of the CSF/serum ratio measured using enzyme immunoassays (EIAs) for SSPE diagnosis remain unclear. To facilitate SSPE diagnosis using EIAs, measles immunoglobulin G (IgG) titers in the CSF and serum of patients with and without SSPE were measured and their CSF/serum antibody ratios evaluated. Serum and CSF antibody levels were compared among three patients with SSPE (59 paired samples), 37 non-SSPE patients, and 2618 patients of unknown backgrounds. Of the 59 paired samples from three patients with SSPE, 56 paired samples (94.9%) showed CSF measles IgG levels ≥0.5 IU/mL and a CSF/serum ratio ≥0.05, whereas non-SSPE cases showed CSF measles IgG levels <0.1 IU/mL and a CSF/serum ratio <0.03. Of the 2618 CSF samples with unknown backgrounds, 951 showed measurable IgG levels with EIA, with a CSF/serum ratio peak of 0.005-0.02, with a 90th percentile of 0.05. Assuming the SSPE criteria as CSF measles IgG ≥0.5 IU/mL and a CSF/serum ratio ≥0.05, only 20 samples (0.8%) with unknown backgrounds were categorized as having SSPE. Conversely, assuming the non-SSPE criteria as CSF measles IgG <0.1 IU/mL and a CSF/serum ratio <0.03, 2403 samples (92%) with unknown backgrounds were categorized as not having SSPE. In conclusion, high CSF/serum ratios (≥0.05) and high measles CSF IgG levels (≥0.5 IU/mL) may be useful for diagnosing SSPE.

Comparison of the diagnostic value of measurements of transverse syndesmotic interval and 'lambda sign' in distinguishing latent syndesmotic diastasis in chronic lateral ankle instability: a cross-sectional study of 188 cases.

Chronic lateral ankle instability (CLAI) could accompany with latent syndesmotic diastasis (LSD), which is difficult to distinguish before surgery. Tibiofibular interval width and extravasation of joint fluid ('lambda sign') on MRI are widely used in the diagnosis of syndesmotic injury, but the reliability of these methods in distinguishing the associated LSD in CLAI was rarely studied. Our objective was to compare the diagnostic value of the measurement of the transverse tibiofibular interval and 'lambda sign' on MRI in distinguishing LSD in CLAI and to investigate the radiological predictor that best matched the intraoperatively measured syndesmotic width. 138 CLAI patients undergoing arthroscopy in our institute from March 2017 to June 2020 were enrolled (CLAI group). Anterior space width (ASW) and posterior space width (PSW) at 10mm layer above tibial articular and fluid height above tibial articular surface (FH) were measured on preoperative MRI. The same parameters were measured on MRI of 50 healthy volunteers as control group. At arthroscopy, syndesmotic width was measured and the patients were divided into arthroscopic widening (AW) and arthroscopic normal (AN) subgroup taking 2mm as critical value. The CLAI group was compared with the control group to explore the interval changes related to CLAI. The AW and AN subgroups were compared to explore the potential diagnostic indicators and reference values for the LSD. All parameters showed significant difference between CLAI group and control group (p < 0.05), but only PSW (p = 0.004) showed significant difference between AW and AN subgroups other than FH (p = 0.461). Only PSW was involved in formula of multiple-factor analysis (p = 0.005; OR, 1.819; 95%CI, 1.196-2.767). ROC analysis showed critical value of PSW was 3.8mm (sensitivity, 66%; specificity, 66%; accuracy, 66.7%), while accuracy of lambda sign was 41.3%. Transverse tibiofibular interval measurements were more reliable than the 'lambda sign' in distinguishing associated LSD in CLAI patients. The PSW ≥ 3.8mm could be a predictor of syndesmotic diastasis.

Ultrasonographic assessment of preoperative gastric volume in patients with dyspepsia: a prospective observational study

BackgroundPatients undergoing gastroenteroscopy during sedation are prone to aspiration, and most patients with dyspepsia have delayed gastric emptying. This study aimed to investigate the feasibility of measuring the gastric antrum cross-sectional area (CSA) to supply a novel clinical diagnostic reference value in patients with dyspepsia.MethodsPatients with dyspepsia undergoing elective gastroscopy were included. The Perlas qualitative 0–2 grading scale score was determined before the operation. The anteroposterior diameter (D1) and craniocaudal diameter (D2) between gastric antrum serosal surfaces were measured perpendicular to each other in the supine and right lateral decubitus (RLD) positions. CSA values in the supine position and RLD position were determined. Gastric contents were endoscopically suctioned with the volumes measured and noted as actual gastric volume. Multiple regression analysis was used to fit a mathematical model for estimating the gastric volume. Receiver operating characteristic (ROC) curves were constructed to determine the accuracy of RLD CSA to detect gastric volumes of > 0.8 ml/kg.ResultsA total of 117 patients were enrolled and divided into a functional dyspepsia (FD) group and an organic dyspepsia group according to gastroscopy findings. For a gastric volume of > 0.8 ml/kg, cut-off values for FD and organic dyspepsia were 6.7 cm2 and 10.0 cm2, respectively. Two new modified mathematical models were derived to predict an estimated gastric volume for FD and organic dyspepsia: volume = 3.93 × RLD CSA - 0.47 × age; and volume = 6.15 × RLD CSA - 0.61 × age.ConclusionWe used the cut-off value of the antral area for the fast diagnosis of gastric volumes in patients with dyspepsia, which may assist clinicians in identifying patients at risk of aspiration.Trial registrationwww.chictr.org.cn (CHICTR-DDD-17010871); registered 15 March 2017.

RETRACTED: Real time monitoring of medical images and nursing intervention after heart valve replacement

Heart valve surgery is a leak reduction or repair operation or replacement of the infected valve. To alleviate the symptoms of valvular heart disease, it can prevent permanent damage to the heart. Heart valve surgery is normally open-heart surgery. This means cutting the sternum and to reach the heart. However, in response to the problems and other factors, there may be a procedure of other alternatives. Echocardiography and fluoroscopy is the main technique used for evaluation of the Prosthetic Heart Valve (PHV), for a particular cause restriction, they are the degree of morphological substrate or PHV pathology it cannot identify. Cardiac computed tomography or magnetic resonance imaging has become the new imaging modalities for the valve prosthesis. It propose the possibility of a systematic literature review based on all of the experiments and the patient's study. Pitfalls of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) provide an overview of the evaluation of the PHV. Metal artifacts might interfere with prosthetics analyzed directly in the MRI, provides information about the flow pattern and velocity associated with PHV. MRI shows an abnormal, asymmetric flow pattern of PHV barriers, enables the evaluation of repair reflux. Therefore, it offers great clinical relevance as a complementary imaging tool for diagnosing CT suspected PHV disorders and endocarditis. MRI is more research to enable a normal identification from pathological conditions required to provide a diagnostic reference value, to be used for functional PHV evaluation potential shows.

Estimation of radiation exposure of children undergoing superselective intra-arterial chemotherapy for retinoblastoma treatment: assessment of local diagnostic reference levels as a function of age, sex, and interventional success

PurposeThis study aims to determine local diagnostic reference levels (LDRLs) of intra-arterial chemotherapy (IAC) procedures of pediatric patients with retinoblastoma (RB) to provide data for establishing diagnostic reference levels (DRLs) in pediatric interventional radiology (IR).MethodsIn a retrospective study design, LDRLs and achievable dose (AD) were assessed for children undergoing superselective IAC for RB treatment. All procedures were performed at the flat-panel angiography systems (I) ArtisQ biplane (Siemens Healthineers) and (II) Allura Xper (Philips Healthcare). Patients were differentiated according to age (A1: 1–3 months; A2: 4–12 months; A3: 13–72 months; A4: 73 months–10 years; A5: > 10 years), sex, conducted or not-conducted chemotherapy.Results248 neurointerventional procedures of 130 pediatric patients (median age 14.5 months, range 5–127 months) with RB (68 unilateral, 62 bilateral) could be included between January 2010 and March 2020. The following diagnostic reference values, AD, and mean values could be determined: (A2) DRL 3.9 Gy cm2, AD 2.9 Gy cm2, mean 3.5 Gy cm2; (A3) DRL 7.0 Gy cm2, AD 4.3 Gy cm2, mean 6.0 Gy cm2; (A4) DRL 14.5 Gy cm2, AD 10.7 Gy cm2, mean 10.8 Gy cm2; (A5) AD 8.8 Gy cm2, mean 8.8 Gy cm2. Kruskal-Wallis-test confirmed a significant dose difference between the examined age groups (A2–A5) (p < 0.001). There was no statistical difference considering sex (p = 0.076) and conducted or not-conducted chemotherapy (p = 0.627). A successful procedure was achieved in 207/248 cases.ConclusionWe report on radiation exposure during superselective IAC of a pediatric cohort at the German Retinoblastoma Referral Centre. Although an IAC formally represents a therapeutic procedure, our results confirm that radiation exposure lies within the exposure of a diagnostic interventional procedure. DRLs for superselective IAC are substantially lower compared with DRLs of more complex endovascular interventions.

Diagnostic reference values for sarcopenia in Tibetans in China

Sarcopenia is an age-associated disease characterized by loss of muscle mass and function, but the diagnostic cutoff values remain controversial. To investigate the diagnostic cutoff values and incidence of sarcopenia in a plateau population, the limb skeletal muscle mass, gait speed and grip strength of 2318 Tibetan adults were measured according to the criteria of the Asian Working Group for Sarcopenia. We found that the diagnostic reference values for sarcopenia in the high-altitude population were significantly lower than those in the plain population, and the incidences of sarcopenia in the high-altitude population over 60 years old were 17.2% in men and 36.0% in women, which were significantly higher than those in the plain population. Our study proposes reference values for the diagnosis of sarcopenia in Tibet. We suggest that the cutoff value for sarcopenia in the plateau population should be established based on altitude. Hypoxia may be an important risk factor for sarcopenia.

Design and first results of a phantom study on the suitability of iterative reconstruction for lung-cancer screening with low-dose computer tomography

Abstract In this research computer tomography (CT) iterative reconstruction (IR) algorithms are investigated, specifically the impact of their statistical and model-based strength on image quality in low-dose lung screening CT protocols in comparison to filtered back projection (FBP). It has been probed whether statistical, model-based IR in conjunction with low-dose, and ultra-low-dose protocols are suitable for lungcancer screening. To this end, artificial lung nodules shaped as spheres and spicules made from material with calibrated Hounsfield units (HU) were attached on marked positions in the lung structure of an anthropomorphic phantom. Nodule positions were selected by distinguished radiologists. The phantom with nodules was scanned on a CT Scanner using standard high contrast (SHC), low-dose (LD) and ultra low-dose (ULD) protocol. For reconstruction FBP and the IR algorithm ADMIRE at three different strength levels were used. Volume CT dose index (CTDIvol) and dose-length product were recorded. Radiologists assessed subjective image quality using a six-point Likert scale by reading all image series in terms detectability of lung nodules. As a measurable objective image quality parameter signal-to-noise ratios (SNR) were investigated. The CTDIvol decreases by more than 70% for all protocols and nodules compared to diagnostic reference value for chest CT (p&lt;0.00001). The evaluation of image quality parameters, i.e. SNR, indicates that LD and ULD protocols in conjunction with IR assert high quality lung-nodule detection. The results reveal that IR algorithm with moderate to high strength is an indispensable alternative to FBP in low-dose scanning, thus, potentially suitable for lung-tumour screening.

Challenges in investigating patients with isolated decreased serum IgM: The SIMcal study.

The clinical consequences of isolated decreased serum immunoglobulin (Ig)M are not sufficiently known. Therefore, it is difficult to determine the clinical policy following such a finding. Only few reported IgM‐deficient patients fulfil the European Society for Immunodeficiencies (ESID) diagnostic criteria for selective IgM deficiency (true sIgMdef), or their diagnosis is uncertain due to insufficient laboratory data (possible sIgMdef). Decreased serum IgM is often incidentally found in asymptomatic adults. The objective of our study was to further characterize true sIgMdef and to compare the European data collected through the ESID Registry community (tertiary centres) to our previously published Dutch cohort (secondary centre). Fifteen centres (12 countries) participated with 98 patients. Patients were excluded if serum IgM was only determined once (n = 14), had normalized (n = 8), or if they also had other immunological abnormalities (n = 15). Ten patients (5 adults) completely fulfilled the ESID criteria for true sIgMdef. Age‐matched cut‐off values varied widely between centres; when using the ESID diagnostic protocol reference values, only six patients (five adults) had true sIgMdef. Because of these small numbers, further analyses were performed in patients with true or possible sIgMdef (13 adults, 48 children). Respiratory infections were commonly reported at presentation (adults 54%, children 60%). Symptomatic adults had lower serum IgM levels (mean 0.27 g/L, 95% CI 0.22‐0.31) than those without symptoms (mean 0.33 g/L, 95% CI 0.30‐0.36; P = 0.02). To be able to explore the clinical consequences of true sIgMdef, we should fully analyse and accurately describe those patients in whom a decreased serum IgM is found.

Comparison of a personalized breast dosimetry method with standard dosimetry protocols

Average glandular dose (AGD) in digital mammography crucially depends on the estimation of breast glandularity. In this study we compared three different methods of estimating glandularities according to Wu, Dance and Volpara with respect to resulting AGDs. Exposure data from 3050 patient images, acquired with a GE Senographe Essential constituted the study population of this work. We compared AGD (1) according to Dance et al. applying custom g, c, and s factors using HVL, breast thickness, patient age and incident air kerma (IAK) from the DICOM headers; (2) according to Wu et al. as determined by the GE system; and (3) AGD derived with the Dance model with personalized c factors using glandularity determined with the Volpara (Volpara Solutions, Wellington, New Zealand) software (Volpare AGD). The ratios of the resulting AGDs were analysed versus parameters influencing dose. The highest deviation between the resulting AGDs was found in the ratio of GE AGD to Volpara AGD for breast thicknesses between 20 and 40 mm (ratio: 0.80). For thicker breasts this ratio is close to one (1 ± 0.02 for breast thicknesses >60 mm). The Dance to Volpara ratio was between 0.86 (breast thickness 20–40 mm) and 0.99 (>80 mm), and Dance/GE AGD was between 1.07 (breast thickness 20–40 mm) and 0.98 (41–60, and >80 mm). Glandularities by Volpara were generally smaller than the one calculated with the Dance method. This effect is most pronounced for small breast thickness and older ages. Taking the considerable divergences between the AGDs from different methods into account, the selection of the method should by done carefully. As the Volpara method provides an analysis of the individual breast tissue, while the Wu and the Dance methods use look up tables and custom parameter sets, the Volpara method might be more appropriate if individual ADG values are sought. For regulatory purposes and comparison with diagnostic reference values, the method to be used needs to be defined exactly and clearly be stated. However, it should be accepted that dose values calculated with standardized models, like AGD and also effective dose, are afflicted with a considerable uncertainty budgets that need to be accounted for in the interpretation of these values.

Thoracic Idiopathic Scoliosis: Establishing the Diagnostic Accuracy and Reference Values of Surface Topography

Objective: The aim of this study was to establish the diagnostic accuracy and cut-off points of the surface topography parameters.

317. Administered activities and effective dose optimization in 18F-FDG PET/CT and 123I-MIBG SPECT/CT examinations in patients during oncology follow-up

Purpose The evaluation of the mean effective dose (ED) in repeated nuclear medicine scans in order to optimize the administered activity in 18 F-FDG PET/CT [1] and 123 I-MIBG SPECT/CT [2] acquisitions in adult and paediatric patients (pts) respectively, during oncology follow-up. Materials and methods SPECT-CT acquisitions were performed by Symbia T2, Siemens. The CT acquisition was performed using a tube current modulation system. Parameters used were: tube current of 30–60 mAs, slice thickness of 5 mm, pitch 2 and tube voltage of 110 kV. Whole body scans were assessed by Discovery 710 Elite (GE) PET/CT equipment. The CT acquisitions parameters were as follows: 120 kV tube voltage, 18–60 mAs tube current, 3.75 mm slice width, 0.6 s rotation time. The activities administered to the pts during 4494 18 F-FDG PET/CT and 54 123 I-MIBG SPECT/CT performed at the Nuclear Medicine Department of the Bufalini Hospital (Cesena) were analyzed by acquiring the data relative to the exams done in 2015–2016 directly from the digitalized registration system (ASTRIM). The data processing was realized by using a home-made and web-based software implemented in asp language. The values were divided based on patient’s gender, age and weight. Moreover, it was verified how many times and how often the same pt repeated the exam. Eventually, the total mean EDTOT in male and female was calculated with administered activity by using ICRP128 coefficients (mSv/MBq) and from the CT parameters for PET/CT and SPECT/CT with IMPACT software. Table1 shows the results. The 37% of the pts repeated the 123 I-MIBG SPECT/CT more than three times in two years, while 27,5% of pts performed two times 18 F-FDG PET/CT. Conclusions The diagnostic procedures involving radiations expose pts to a risk of stochastic cancer related to age and gender (figure1). The fulfil of diagnostic reference values for all scans is mandatory, furthermore the administered activity and CT parameters personalisation for adult and paediatric pts, particularly in repeated acquisitions, is of primary importance – always preserving the image quality. Download high-res image (267KB) Download full-size image Download high-res image (256KB) Download full-size image

Illustrations pratiques – aspects pratiques et réglementaires

Quality and regulatory controls in hybrid nuclear medicine, layout and installations constraints, Diagnostic Reference values and regulatory and mandatory information in the medical report are presented in that part.

Clinical Use and Optimal Cutoff Value of Ca15-3 in Evaluation of Adnexal Mass: Retrospective Cohort Study and Review of the Literature.

To estimate the diagnostic performance and reference values of serum cancer antigen (Ca)15-3 levels in the triage of adnexal masses. This retrospective cohort study was carried out in 481 patients referred to the Gynecology Department at Carmel Medical Center due to adnexal mass between years 2005 and 2012. All patients underwent surgery with histopathologically confirmed diagnosis and routine preoperative measurements of serum Ca125 and Ca15-3. Combination of Ca125 with Ca15-3 elevated the sensitivity of Ca125 alone (from 86.9% to 93.2%; P=0.029), along with reduction of its specificity (from 80.5% to 69.5%; P=0.005) in differentiation between malignant and benign cases. According to receiver operating characteristic curve, Ca15-3 level of 21 U/mL was shown to be the optimal reference value for malignancy detection. All cases with Ca15-3 levels above 44.5 U/mL were malignant, mostly of primary ovarian source. As Ca15-3 assessment allowed detection of significantly more malignancy cases, we believe that measurement of this marker in combination with Ca125 is worthwhile in patients presenting with adnexal masses. The cutoff of 21 U/mL seems to be the optimal value in this specific population. High Ca15-3 levels (above 44.5 U/mL) strongly direct to a diagnosis of malignancy, mostly of primary ovarian tumors rather than breast malignancy.

P034] Implementation of a dose data collection software system: Structure of data and CT preliminary results

Purpose CT protocols review and optimization require a considerable amount of time and dedicated staff especially to compare dose levels among multicentre institutions and with national and international average values. The purpose of this article is to describe the structure of data collection for a dose radiation tracking software used to analyse a large amount of CT dose data. This should be done in order to audit scanner protocols, improve staff and patient safety and optimize all the diagnostic workflow. Methods The software implementation team included a team leader, two radiology technologists, two medical physicists and the chief of radiology department. Very detailed data collection folders and diagnostic reference values (DRV) were created based on 25th percentile, as target value, and 75th percentile, as upper limit, values of CTDIvol and DLP extracted from Swiss CT DRV. Data were collected from seven different multislice CT scanners using the study description Dicom tag. Results Direct protocol comparison, for each institution/scanner, is presented. About 90% of CT exams applied a dose inferior to Swiss DRV. Conclusions DVRs represent a benchmark useful to optimize radiation dose. Multisite cross-analysis of CT protocols allows the adoption of the best dose-optimized protocols in each center. Outliers and dose reduction strategies are discussed periodically within a team meeting: analyses are performed using a Montecarlo simulation tool to optimize future exams by varying setup parameters and study length. On request, total effective and individual organ dose values, are available especially for pregnant patients immediately after diagnostic examinations.