Fetal age estimation using MSCT scans of the mandible

The purpose of this study was to examine a documented fetal collection, to carry out morphometric analysis of femoral length and of the mandible, and to develop diagnostic standards for estimating fetal age at death based on multislice computed tomography (MSCT) reconstructions. The sample was composed of 81 fetuses, whose ages were recorded in weeks of amenorrhea (WA) between 20 to 40 WA. The measurements made were femoral length (FL) and six distances and four angles of the mandible. Femoral length was measured in 81 fetuses (39 females and 42 males). Morphometric study of the mandible was carried out in 65 fetuses (31 females and 34 males), as the mandible was missing in 16 fetuses. R software was used for statistical analyses. Coefficient correlation (R²) and linear regression formulas were calculated. Intra-observer and inter-observer variabilities were very satisfactory (intra-class correlation coefficient ≥0.95). Our method appears to be reliable and reproducible. Femoral length was most strongly correlated with age (R²?=?0.9). The measurement of six distances and four mandible angles from four landmark positions showed a correlation similar to the femoral length correlation (R²?≥?0.72). The results of this study agreed with those of the literature. We conclude that the mandible is a reliable indicator for estimating fetal age at death. Moreover, MSCT has been shown to be an innovative and reliable technology for this purpose.     

Fetal MRI with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) assessment in the evaluation of renal development: preliminary experience in normal kidneys

Purpose

The study aimed to investigate the correlation between apparent diffusion coefficient (ADC) and gestational age by applying diffusion-weighted imaging (DWI) in the study of normal fetal kidneys.

Materials and methods

We performed magnetic resonance (MR) imaging on 88 fetuses (gestational age range 17–40 weeks) after ultrasound had ruled out urinary system malformations. A multiplanar study of the urinary system was obtained by using conventional T2-weighted sequences and echoplanar imaging (EPI). DW sequences with ADC maps were subsequently acquired, and kidney ADC values were correlated with gestational age by diving the fetuses into six groups according to age.

Results

We found a correlation between ADC values and gestational age. The ADC values, ranging from 0.99 to 1.62×10^?3 mm²/s [mean 1.22; 95% confidence interval (CI) 1.19–1.25, standard deviation (SD) 0.147], showed a tendency to decrease with increasing gestational age. The relationship between ADC values and gestational age was expressed by a linear regression equation: ADC (mm²/s)=1.69–0.0169 (GA) (R²=37.7%, R² ADJ=37.0%, p<0.005, Pearson correlation=?0.614).

Conclusions

DWI with ADC mapping provides functional information on fetal renal parenchyma development and may thus become a useful tool in the management of pregnancy and treatment of the newborn child.     

Dental radiographic information of term newborn babies within the first month: Analyzing five radiographic cases along with physical attributes in Japan

BackgroundAlthough dental radiography is a valuable tool for age estimation in forensic anthropology and odontology, very limited radiological data are available regarding tooth development in healthy newborn babies during the first month of life.AimThis study aimed to describe the radiological findings of tooth development in babies aged 0 days to 1 month.DesignWe analyzed the postmortem findings of five newborn babies with no known natural cause of death who had undergone autopsy, computed tomography (CT), and dental radiography. We estimated the gestational age for the babies aged 0 days and analyzed the condition of mandibular symphysis, existence of tooth germs, and presence or absence of calcification of the first permanent molars of all the babies.ResultsThe calcified form of 20 deciduous teeth, tooth germs of the permanent upper and lower first molars, and non-calcified mandibular symphysis were observed in each case. However, calcification of the first permanent molar was observed in only two 1-month-old babies.ConclusionThe dental radiographic findings and anthropometric measurements of non-skeletonized, non-mummified term babies confirmed calcification of all the deciduous teeth and the first permanent molar at the age of 0 days and 1 month, respectively.     

Deciduous teeth development in fetuses using postmortem computed tomography image analysis

Fetal age is estimated widely by body length and weight and skeletal or dental development and maturation. Regarding dental development, dental development charts reported by Schour and Massler and Ubelaker are well known. We tried to calculate the calcification rate of the deciduous teeth, mandibular cortical bone, and clavicle in fetuses utilizing postmortem computed tomography (CT) image analysis. The CT values within the circumferential area of the region of interest were automatically calculated using a software, and the calcification rate was calculated by performing single regression analysis. Our results showed that deciduous tooth calcification could be detected in over 19-week-old fetuses using CT images. The calcification of bones (mandibular cortical bone and clavicle) started earlier than the calcification of deciduous teeth. However, the calcification rate of the bones was slower compared to that of the deciduous teeth. The calcification rate of the deciduous teeth in fetuses using CT value may be effective to estimate fetal age and evaluate deciduous teeth development, suggesting that our established method is effective for age estimation in forensic dentistry.     

Cardiac valve calcifications on low-dose unenhanced ungated chest computed tomography: inter-observer and inter-examination reliability,agreement and variability

Objectives

To determine inter-observer and inter-examination variability for aortic valve calcification (AVC) and mitral valve and annulus calcification (MC) in low-dose unenhanced ungated lung cancer screening chest computed tomography (CT).

Methods

We included 578 lung cancer screening trial participants who were examined by CT twice within 3 months to follow indeterminate pulmonary nodules. On these CTs, AVC and MC were measured in cubic millimetres. One hundred CTs were examined by five observers to determine the inter-observer variability. Reliability was assessed by kappa statistics (κ) and intra-class correlation coefficients (ICCs). Variability was expressed as the mean difference ± standard deviation (SD).

Results

Inter-examination reliability was excellent for AVC (κ?=?0.94, ICC?=?0.96) and MC (κ?=?0.95, ICC?=?0.90). Inter-examination variability was 12.7?±?118.2 mm³ for AVC and 31.5?±?219.2 mm³ for MC. Inter-observer reliability ranged from κ?=?0.68 to κ?=?0.92 for AVC and from κ?=?0.20 to κ?=?0.66 for MC. Inter-observer ICC was 0.94 for AVC and ranged from 0.56 to 0.97 for MC. Inter-observer variability ranged from -30.5?±?252.0 mm³ to 84.0?±?240.5 mm³ for AVC and from -95.2?±?210.0 mm³ to 303.7?±?501.6 mm³ for MC.

Conclusions

AVC can be quantified with excellent reliability on ungated unenhanced low-dose chest CT, but manual detection of MC can be subject to substantial inter-observer variability. Lung cancer screening CT may be used for detection and quantification of cardiac valve calcifications.

Key points

? Low-dose unenhanced ungated chest computed tomography can detect cardiac valve calcifications. ? However, calcified cardiac valves are not reported by most radiologists. ? Inter-observer and inter-examination variability of aortic valve calcifications is sufficient for longitudinal studies. ? Volumetric measurement variability of mitral valve and annulus calcifications is substantial.     

Assessment of global cardiac I-123 MIBG uptake and washout using volumetric quantification of SPECT acquisitions

Background

Assessment of cardiac innervation using single-photon emission computer tomography (SPECT) is less established than planar imaging, but may be more suitable for quantification. Therefore, a volumetric quantification of I-123 MIBG SPECT acquisitions was performed. Reproducibility, the effects of extra cardiac I-123 MIBG uptake and the relation with conventional planar indices were evaluated.

Methods

54 patients referred for planar and SPECT I-123 MIBG acquisitions were included. Ellipsoidal or box-shaped volumes of interest were placed on the left ventricle, cardiac lumen, mediastinum, lung and liver. SPECT segmentation was performed twice in all patients. Indices were determined based on the heart-to-mediastinum (HM), myocardial wall-to-mediastinum and myocardial wall-to-lumen regions. HM ratios and washout rates were also determined based on anterior planar images.

Results

Cardiac count densities were highly reproducible (CV 1.5-5.4, ICC 0.96-0.99) and inter-rater variability was low (CV 1.8-6.8, ICC 0.94-0.99). Mediastinal uptake was an important explanatory variable of uptake in the entire heart (early R ²?=?0.36; delayed R ² =0.43) and myocardial wall (early R ²?=?0.28; delayed R ²?=?0.37). Lung washout was an explanatory variable of organ washout of the heart (heart R ²?=?0.38; myocardial wall R ²?=?0.33). In general, SPECT indices showed moderate-to-good correlations with the planar uptake (PCC 0.497-0.851).

Conclusion

By applying a volumetric segmentation method we were able to segment the heart in all patients. SPECT I-123 MIBG quantification was found to be highly reproducible and had a moderate to good correlation with the planar indices.     

Evaluation of the maximum length of deciduous teeth for estimation of the age of infants and young children: proposal of new regression formulas

The methodology used to identify individuals in forensic anthropology requires a minimum degree of precision and accuracy and should be based on identified and representative samples. Achievement of these objectives in infant skeletons is hampered by the scarcity of appropriate samples. The dental age estimation methods of Liversidge et al. (Am J Phys Anthropol 90: 307–313, 1993) and Deutsch et al. (Growth 49: 207–17, 1985) were applied to the Granada osteological collection of identified infants (Granada, Spain) in order to evaluate its applicability in a Mediterranean population. Significant differences were found between the estimated and real ages in both cases. Based on the measurements obtained in 140 fetuses and infants, new regression formulas were developed to estimate age from the metric study on deciduous teeth. Independent functions are provided for each deciduous maxillary and mandibular tooth in each sex, along with the margin of error (95 % confidence interval). These formulas appear to offer one of the best methods available for estimating the age of Mediterranean infants in forensic anthropology settings.     

Reliability of performing ultrasound derived SWE and fat fraction in adult livers

PurposeThe aim of the study was to test the reproducibility of performing conventional point shear wave elastography (pSWE), auto-pSWE, and ultrasound derived fat fraction (UDFF) in adult livers.MethodsThe Institutional Review Board approved the study and all participants provided written informed consent. Conventional pSWE (obtaining 10 measurements through 10 acquisitions), auto-pSWE (automatically obtaining 15 measurements by a single acquisition), and UDFF (one measurement obtained by one acquisition) of the liver were prospectively performed in 21 participants (10 men, 11 women, mean age 63y) by senior and junior operators in February-May 2021. Shear wave velocity (SWV, m/s) of the liver was measured by conventional pSWE and auto-pSWE. Intraclass correlation coefficient (ICC) and Bland-Altman limits of agreement were used to test intra-observer repeatability and inter-observer reproducibility in measuring pSWE, auto-pSWE, and UDFF.ResultsICC for testing intra-observer repeatability and inter-observer reproducibility in performing pSWE, auto-pSWE, and UDFF was >0.85 (95% confidence interval 0.85-0.99). The mean difference of 95% Bland-Altman limits of agreement was -0.02 (upper 0.09, lower -0.12) and the correlation of SWV measured between conventional pSWE and auto-pSWE methods was strong (r² = 0.87).ConclusionOur results suggest good repeatability and reproducibility in measuring UDFF and SWV in adult livers. The auto-pSWE has higher reliability, reproducibility and time efficacy in measuring SWV of adult livers when compared to conventional pSWE method.     

Reproducibility and criterion-related validity of the sit and reach test and toe touch test for estimating hamstring flexibility in recreationally active young adults

Objective1) to examine the test-retest reproducibility and criterion-related validity of the sit and reach test (SRT) and the toe touch test (TT) for estimating hamstring flexibility measured through the passive straight leg raise test (PSLR); and 2) to determine whether the SRT cut-off scores may be used for the TT test to identify participants in this sample of young healthy adults as having short hamstring flexibility.DesignTest-retest design.SettingControlled laboratory environment.Participants243 active recreationally young adults.Main outcome measuresParticipants performed the SRT, the TT test and PSLR twice in a randomized order with a 4-week interval between trials. Reproducibility was examined using typical percentage error (coefficient of variation [CV]) and intraclass correlation coefficient (ICC) as well as their respective confidence limits. Regression and Kappa correlation statistical analyses were performed to study the association of the SRT and TT test with the PSLR test and the 95% limits of agreement (LoA) between SRT and TT test were calculated to explore differences in the mean differences between these measurements.ResultsThe finding showed acceptable reproducibility measures for SRT (8.74% CV; 0.92 ICC), TT test (9.86% CV; 0.89 ICC) and PSLR (5.46% CV; 0.85 ICC). The SRT (R² = 0.63) and TT test (R² = 0.49) were significantly associated with PSLR. The 95% LoA between SRT and TT test reported systematic bias (2.84 cm) and wide 95% random error (±9.72 cm).ConclusionsReproducibility of SRT, TT test and PSLR is acceptable and the criterion-related validity of SRT and TT test is moderate. Furthermore, the SRT cut-off scores should not be used for TT test for the detection of short hamstring muscles.     

New Ultrasound Measurements to Bridge the Gap between Prenatal and Neonatal Brain Growth Assessment

BACKGROUND AND PURPOSE:Most ultrasound markers for monitoring brain growth can only be used in either the prenatal or the postnatal period. We investigated whether corpus callosum length and corpus callosum–fastigium length could be used as markers for both prenatal and postnatal brain growth.MATERIALS AND METHODS:A 3D ultrasound study embedded in the prospective Rotterdam Periconception Cohort was performed at 22, 26 and 32 weeks'' gestational age in fetuses with fetal growth restriction, congenital heart defects, and controls. Postnatally, cranial ultrasound was performed at 42 weeks'' postmenstrual age. First, reliability was evaluated. Second, associations between prenatal and postnatal corpus callosum and corpus callosum–fastigium length were investigated. Third, we created reference curves and compared corpus callosum and corpus callosum–fastigium length growth trajectories of controls with growth trajectories of fetuses with fetal growth retardation and congenital heart defects.RESULTS:We included 199 fetuses; 22 with fetal growth retardation, 20 with congenital heart defects, and 157 controls. Reliability of both measurements was excellent (intraclass correlation coefficient ≥ 0.97). Corpus callosum growth trajectories were significantly decreased in fetuses with fetal growth restriction and congenital heart defects (β = −2.295; 95% CI, −3.320–1.270; P < .01; β = −1.267; 95% CI, −0.972–0.562; P < .01, respectively) compared with growth trajectories of controls. Corpus callosum–fastigium growth trajectories were decreased in fetuses with fetal growth restriction (β = −1.295; 95% CI, −2.595–0.003; P = .05).CONCLUSIONS:Corpus callosum and corpus callosum–fastigium length may serve as reliable markers for monitoring brain growth from the prenatal into the postnatal period. The clinical applicability of these markers was established by the significantly different corpus callosum and corpus callosum–fastigium growth trajectories in fetuses at risk for abnormal brain growth compared with those of controls.

In preterm infants and those small-for-gestational age, brain growth is an important predictor of neurodevelopmental outcome.^1–4 Although prenatal growth often predicts postnatal growth, there is a traditional division between fetal and neonatal growth charts.⁵ This is mainly due to the lack of consistent measures of brain growth that can be used in both the prenatal and postnatal periods.Markers of brain growth that can theoretically be used in both the prenatal and postnatal periods include head circumference and a few ultrasound (US) and MR imaging measures. Head circumference measured postnatally, however, lacks precision and does not correspond well with neurodevelopmental outcome.^6,7 Prenatal and postnatal US markers are largely based on individual brain structures, only reflecting growth of a specific part of the brain.^8–12 Moreover, these brain structures are not measured consistently during the prenatal and postnatal periods due to the absence of corresponding standard US planes. Although MR imaging provides more precise measures of brain growth, volume, and development, this technique is expensive and therefore not suitable for serial measurements.Recently, we demonstrated that corpus callosum–fastigium (CCF) length is a reliable bedside-available US marker that can be used to monitor brain growth in preterm infants during neonatal intensive care unit stays.¹³ CCF length is considered a composite marker of diencephalon and mesencephalon size and thereby adds information to the more widely used corpus callosum (CC) length.¹³ We hypothesized that these 2 cranial ultrasound measures are feasible for use during prenatal US examinations. Thereby, these markers would provide a continuum for monitoring brain growth, bridging the period before and after birth.Our main aim was to investigate whether CC and CCF lengths can be used as reliable US markers for monitoring fetal and neonatal brain growth. First, we assessed the reliability of the measurements. Second, we created reference curves from 22 to 42 weeks'' gestational age (GA) by combining fetal and neonatal measurements. Finally, as a first step to evaluate the clinical applicability of these US markers, we investigated CC and CCF growth trajectories in fetuses at risk of abnormal brain growth and compared them with those of control fetuses.     

Sonographic determination of fetal gender in the second and third trimesters in a private hospital in Enugu,southeast Nigeria

BackgroundPregnant Nigeria women are usually anxious about the gender of their fetuses for social reasons.ObjectiveThe purpose of this study was to determine the accuracy of ultrasound in the determination of fetal gender in women who wished to know the gender of their fetuses and in those whom the gender of their fetuses were requested for on clinical grounds in the second and third trimesters.MethodsA prospective longitudinal study was performed on 1480 singleton pregnancies who met the inclusion criteria between February 2004 and January 2008. Ultrasound examination was performed on GE ALOKA 500 machine, transabdominally between 14 and 40 weeks gestational age (GA). Both transverse and mid-sagittal planes of a section of the fetal genital tubercle were performed to identify the gender. The subsequent gender at birth was obtained from the hospital birth records.ResultsDuring the study, 1211 (81.8%) women requested gender information while the gender information from 269 (18.2%) women was requested for on clinical grounds. The mean GA at which the fetuses were scanned was 29⁺² ± 3⁺⁶ weeks (range 14–40 weeks). Fetal gender assignment was possible in 1350 (91.2%) out of 1480 fetuses; 680 assigned male and 670 female. Of these, the fetal gender corroborated birth sex in 1325 (89.5%) and disagreed in 25 (1.7%) cases. The overall estimated sensitivity of the scan is 98.1%, while the estimated specificity for identification of the male sex (100%) was higher than the female (78.3%). Of the 130 cases where no identification of gender was possible, 50 were in the second trimester and 80 were in the third trimester.ConclusionThis study demonstrated that the accuracy of fetal gender determination increased with gestational age, from 97.1% in the second trimester to 98.5% in the third trimester. The overall fetal gender accuracy rate for male fetus was better than female and was statistically significant (P < 0.05).     

Functional imaging of head and neck squamous cell carcinoma with diffusion-weighted MRI and FDG PET/CT: quantitative analysis of ADC and SUV

Purpose

Head and neck squamous cell carcinoma (HNSCC) may cause a decreased apparent diffusion coefficient (ADC) on diffusion-weighted magnetic resonance imaging (DW MRI) and an increased standardized uptake value (SUV) on fluorodeoxyglucose (FDG) positron emission tomography (PET/CT). We analysed the reproducibility of ADC and SUV measurements in HNSCC and evaluated whether these biomarkers are correlated or independent.

Methods

This retrospective analysis of DW MRI and FDG PET/CT data series included 34 HNSCC in 33 consecutive patients. Two experienced readers measured tumour ADC and SUV values independently. Statistical comparison and correlation with histopathology was done. Intra- and inter-observer agreement for ADC and SUV measurements was assessed.

Results

Intraclass correlation coefficient (ICC) analysis showed almost perfect reproducibility (>0.90) for ADC_mean, ADC_min, SUV_max and SUV_mean values for intra-observer and inter-observer agreement. Mean ADC_mean and ADC_min in HNSCC were 1.05?±?0.34 × 10^?3?mm²/s and 0.65?±?0.29 × 10^?3?mm²/s, respectively. Mean SUV_mean and mean SUV_max were 7.61?±?3.87 and 12.8?±?5.0, respectively. Although statistically not significant, a trend towards higher SUV and lower ADC was observed with increasing tumour dedifferentiation. Pearson’s correlation analysis showed no significant correlation between ADC and SUV measurements (r ?0.103, ?0.051; p 0.552, 0.777).

Conclusion

Our data suggest that ADC and SUV values are reproducible and independent biomarkers in HNSCC.     

Quantitative elastography of renal transplants using supersonic shear imaging: a pilot study

Purpose

To evaluate the reliability of quantitative ultrasonic measurement of renal allograft elasticity using supersonic shear imaging (SSI) and its relationship with parenchymal pathological changes.

Materials and methods

Forty-three kidney transplant recipients (22 women, 21 men) (mean age, 51?years; age range, 18–70?years) underwent SSI elastography, followed by biopsy. The quantitative measurements of cortical elasticity were performed by two radiologists and expressed in terms of Young’s modulus (kPa). Intra- and inter-observer reproducibility was assessed (Kruskal-Wallis test and Bland-Altman analysis), as well as the correlation between elasticity values and clinical, biological and pathological data (semi-quantitative Banff scoring). Interstitial fibrosis was evaluated semi-quantitatively by the Banff score and measured by quantitative image analysis.

Results

Intra- and inter-observer variation coefficients of cortical elasticity were 20?% and 12?%, respectively. Renal cortical stiffness did not correlate with any clinical parameters, any single semi-quantitative Banff score or the level of interstitial fibrosis; however, a significant correlation was observed between cortical stiffness and the total Banff scores of chronic lesions and of all elementary lesions (R?=?0.34, P?=?0.05 and R?=?0.41, P?=?0.03,respectively).

Conclusion

Quantitative measurement of renal cortical stiffness using SSI is a promising non-invasive tool to evaluate global histological deterioration.

Key Points

? Supersonic shear imaging elastography can measure cortical stiffness in renal transplants ? The level of cortical stiffness is correlated with the global degree of tissue lesions ? The global histological deterioration of transplanted kidneys can be quantified using elastography     

Quantification of aortic valve stenosis in MRI—comparison of steady-state free precession and fast low-angle shot sequences

We compared two different magnetic resonance (MR) sequences [steady-state free precession (SSFP) and gradient echo fast low-angle shot (FLASH)] for the assessment of aortic valve areas in aortic stenosis using transesophageal echocardiography (TEE) as the standard of reference. Thirty-two patients with known aortic stenosis underwent MR (1.5 T) using a cine SSFP sequence and a cine FLASH sequence. Planimetry was performed in cross-sectional images and compared to the results of the TEE. In seven patients the grade of stenosis was additionally assessed by invasive cardiac catheterization (ICC). The mean aortic valve area measured by TEE was 0.97±0.19 mm², 1.00±0.25 mm² for SSFP and 1.25±0.23 mm² based on FLASH images. The mean difference between the valve areas assessed based on SSFP and TEE images was 0.15±0.13 cm² (FLASH vs TEE: 0.29±0.17 cm²). Bland-Altman analysis demonstrated that measurements using FLASH images overestimated the aortic valve area compared to TEE. Comparing ICC with MRI and TEE, only a weak to moderate correlation was found (ICC vs TEE: R=0.52, p=0.22; ICC vs SSFP: R=0.20, p=0.65; ICC vs FLASH: R=0.16, p=0.70). Measurements of the aortic valve area based on SSFP images correlate better with TEE compared to FLASH images.     

Apparent diffusion coefficient modifications in assessing gastro-oesophageal cancer response to neoadjuvant treatment: comparison with tumour regression grade at histology

Objectives

To assess changes in apparent diffusion coefficient (ΔADC) and volume (ΔV) after neoadjuvant treatment (NT), and tumour regression grade (TRG) in gastro-oesophageal cancers (GEC), and to discriminate responders from non-responders.

Methods

Thirty-two patients with biopsy-proven locally-advanced GEC underwent diffusion weighted magnetic resonance imaging (DWI) pre- and post-NT. Lesion ADC, volume, ΔADC and ΔV were calculated. TRG 1-2-3 patients were classified as R; TRG 4-5 as non-responders. ΔADC-TRG and ΔV-TRG correlations, pre-NT and post-NT ADC, ΔADC and ΔV cut-off values for responders and non-responders were calculated. Two readers measured mean tumour ADCs and interobserver variability was calculated. (Spearman’s and intraclass correlation coefficient [ICC]).

Results

The interobserver reproducibility was very good both for pre-NT (Spearman’s rho?=?0.8160; ICC?=?0.8993) and post-NT (Spearman’s rho?=?0.8357; ICC?=?0.8663). Responders showed lower pre-NT ADC (1.32 versus 1.63?×?10^?3?mm²/s; P?=?0.002) and higher post-NT ADC (2.22 versus 1.51?×?10^?3?mm²/s; P?=?0.001) than non-responders and ADC increased in responders (ΔADC, 85.45 versus ?8.21 %; P?=?0.00005). ΔADC inversely correlated with TRG (r?=??0.71, P?=?0.000004); no difference in ΔV between responders and non-responders (?50.92 % versus ?14.12 %; P?=?0.068) and no correlation ΔV-TRG (r?=?0.02 P?=?0.883) were observed.

Conclusions

The ADC can be used to assess gastro-oesophageal tumour response to neoadjuvant treatment as a reliable expression of tumour regression.

Key Points

? DWI is now being used to assess many cancers. ? Change in ADC measurements offer new information about oesophageal tumours. ? ADC changes are more reliable than dimensional criteria in assessing neoadjuvant treatment. ? Such ADC assessment could optimise management of locally advanced gastro-oesophageal cancers.     

Two-position supine/prone myocardial perfusion SPECT (MPS) imaging improves visual inter-observer correlation and agreement

Objectives

We aimed to compare the inter-observer agreement between two experienced readers using supine vs combined supine/prone myocardial perfusion SPECT (MPS) in a large population.

Methods

1,181 consecutive patients without known coronary artery disease (CAD) undergoing rest ²⁰¹Tl/stress ^99mTc-sestamibi MPS studies were evaluated. Visual reads were performed in two consecutive steps, with readers scoring the stress supine perfusion images during step 1 and rescoring the images using both supine/prone data during step 2. Visual summed stress scores (SSS) of two readers including regional scores in different vascular territories were compared.

Results

The specificity for both readers improved using combined supine/prone imaging (reader 1: 92% vs 86% [P = .0002], reader 2: 88% vs 72% [P < .0001]). The inter-observer correlation for SSS (0.90 vs 0.84, P < .0001) and inter-observer agreement for combined supine/prone reading (bias = 1.0, 95% confidence interval (CI) 0.9-1.2 vs bias = 3.1, 95% CI 2.8-3.4, P < .0001) were significantly better as compared to supine-only reading. The overall correlation between SSS scores for two readers improved with supine/prone imaging for both genders, as well as in the left anterior descending and right coronary territories.

Conclusion

The inter-observer correlation and agreement significantly improve using two-position supine/prone vs supine-only imaging.     

Magnetic resonance assessment of fetal lung maturity: comparison between signal intensity and volume measurement

Purpose

We evaluated the associations between gestational age (GA) and lung-to-liver signal intensity ratio (LLSIR) and fetal lung volume (FLV) using magnetic resonance imaging (MRI). Moreover, we evaluated the reproducibility of these measurements.

Materials and methods

LLSIR and FLV were measured using single-shot fast spin-echo MRI in 88 consecutive fetuses. The Spearman test was used to assess the relationships between (1) LLSIR and GA, and (2) FLV and GA in 81 fetuses without lung abnormalities. Intra- and inter-observer reliabilities were assessed using intra-class correlation coefficients (ICCs).

Results

Overall, GA and LLSIR were significantly correlated (r?=?0.62, p?<?0.001). However, GA and LLSIR were only significantly correlated during the third trimester (before third trimester: r?=?0.39, p?=?0.08; during third trimester: r?=?0.46, p?<?0.001). Overall, GA and FLV were significantly correlated (r?=?0.72, p?<?0.001). FLV was significantly correlated with GA before (r?=?0.86, p?<?0.001) and during the third trimester (r?=?0.47, p?<?0.001). All ICCs were above 0.90.

Conclusions

LLSIR and FLV are useful for the assessment of fetal lung maturity and are highly reproducible. Before the third trimester, FLV is more suitable than LLSIR for the evaluation of fetal lung maturity.

     

MR assessment of fetal lung development using lung volumes and signal intensities

The purpose of this study was to evaluate the monitoring and diagnostic potential of MRI in fetal lung development and disease using lung volume and signal intensity changes through gestation. Thirty-five healthy fetuses (22–42 weeks) were examined on a 1.5- T MR system using sagittal T2w single-shot fast spin-echo imaging (TR indefinite, TE 90 ms, slice thickness/gap 3–5/0 mm, FOV 26–40 cm, NEX 0.5). Fetal body and lung were segmented manually and volumes calculated. Signal intensities (SI) of fetal lung and three reference values were measured on the section best displaying the lung. Regions of interests were defined by including the maximal organ area possible. The following SI ratios were generated: lung/liver, lung/amniotic fluid, lung/muscle, liver/fluid and liver/muscle. Volumes and ratios were correlated with gestational age. Data from seven fetuses with pulmonary pathology were compared with these normative values. Absolute lung volume varied from 12.3 to 143.5 cm³ in correlation with gestational age (P<0.001); lung volume relative to total body volume ranged from 1.6 to 5.0%, decreasing with gestational age (P=0.001). All SI ratios measured were unrelated to gestational age. Diagnoses in the seven abnormal fetuses were hydrothorax (n=2), congenital cystic adenomatoid malformation (n=2), diaphragmatic hernia (n=2) and pulmonary sequestration (n=1); their absolute and relative lung volumes were below normal (P<0.001). The SI ratios did not differ significantly from those in the normal population. Normative MR fetal lung volumes may have important clinical applications in confirming and quantifying intrauterine pulmonary hypoplasia and in complementing ultrasound in the planning of fetal and post-natal surgery. No clinical relevance was found for fetal lung SI values.