Development of a Nomogram for Fetal Evans Index

Development of a Nomogram for Fetal Evans Index | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Development of a Nomogram for Fetal Evans Index Bedri Sakcak, Atakan Tanacan, Ramazan Denizli, Nihat Farisogullari, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3963802/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose This study aims to investigate the fetal Evans Index and establish a nomogram for fetuses without any additional fetal anomalies detected during the prenatal period. Methods We conducted our research at Ankara City Hospital, including 894 patients who were admitted and evaluated between gestational weeks 16–40. These patients had no fetal anomalies detected in subsequent gestational weeks. Descriptive data, such as age, gravidity, parity, and body mass index (BMI), were recorded. Gestational week and Evans Index (mean, median, standard deviation, minimum, maximum, percentile) were also documented. The Evans index was calculated as the ratio between the maximal width of the frontal horns and the maximal width of the inner diameter of the cranium. Results We evaluated 894 fetuses in pregnant women had no fetal anomalies detected throughout the pregnancy. The evaluation took place at different gestational weeks, and a nomogram for the Evans Index was created. Conclusion It is relevant for clinicians and researchers to be aware of the range of fetal Evans Index values across different gestational weeks as a prognostic criterion. Evans Index fetal ultrasound nomogram Figures Figure 1 Figure 2 What does this study adds to the clinical work? -The identification of a nomogram for the fetal Evans index. -Fetal Evans index may help future physicians to objectively evaluate cases of fetal ventriculomegaly and/or hydrocephaly. Introduction The Evans Index (EI) is defined as the ratio of the maximum width of the anterior horns of the lateral ventricles to the maximum inner diameter of the cranium. It was first proposed by Evans in 1942 and has been used to indirectly evaluate the dilation of the ventricular system[ 1 ]. Several retrospective studies analyzing normal patients at various centers have emphasized that the ratio of the transverse diameter of the anterior horns of the lateral ventricles to the inner diameter of the cranium can be used as an index to evaluate ventricular size. The study concluded that this ratio is within normal limits between 0.2–0.25, represents early or suspected dilation between 0.25–0.30, and values above 0.30 definitively indicate abnormal ventricular dilation [ 2 , 3 ]. Normal pressure hydrocephalus (NPH) is a clinical condition characterized by cognitive impairment, gait disturbance, and urinary incontinence, along with ventricular enlargement, despite normal cerebrospinal fluid (CSF) pressure. It was first described by Dr. Adams and colleagues in 1965 [ 4 ]. NPH is a treatable condition but often goes undiagnosed. Early diagnosis and treatment of NPH is crucial as this can increase the likelihood of a favorable outcome. However, knowledge regarding the utility of this novel index in the fetus is limited and new studies are necessary to determine the reference values of Evans index in the fetal life [ 5 , 6 ]. The Evans index plays a crucial role in diagnosing iNPH (Idiopathic Normal Pressure Hydrocephalus). However, there is a lack of previous epidemiological studies on the values of this index in fetal life. The main purpose of this study is to obtain reference values for the Evans index in normal fetuses from various gestational weeks during the prenatal period and to create a nomogram. Material and Methods This prospective cohort study was conducted at the Perinatology Clinic of the Obstetrics and Gynecology Department of the Turkish Ministry of Health Ankara City Hospital between March 02, 2022, and June 30,2023. The study adhered to the principles of the Declaration of Helsinki and was approved by the Human Ethics Committee of the hospital (number: E2-23-5678). Written informed consent was obtained from all 894 pregnant women at 16–40 weeks of gestation who presented to the perinatology clinic of the hospital between March 2022 and June 2023. Patients with systemic diseases such as kidney disease, diabetes, and hypertension, women with multiple pregnancies, smokers, those with elevated glucose tolerance values, oligohydramnios or polyhydramnios and fetal growth restriction,fetal microcephaly or macrocephaly, fetuses with chromosomal or structural fetal anomalies were excluded from the study. The pregnant women were divided into six groups based on their gestational week: group 0 (16–20), group 1 (21–24), group 2 (25–28), group 3 (29–32), group 4 (33–36), and group 5 (37–40). We calculated the indices of each group separately, including the Evans index (mean, median, standard deviation, minimum, maximum, percentile). The patients' descriptive data, such as age, gestational weeks, and body mass index (BMI), were also noted. Ultrasonography Measurements were conducted using the Voluson S10 ultrasonography device (GE Medical Systems) with a 3.5 MHz convex transducer (6C1-PVT-375BT) transabdominal probe by the same observer (BS) under the supervision of an experienced Professor of maternal fetal medicine (DS). The ultrasound images consisted of transverse sections, following previously described radiologic evaluations. The Evans index was calculated as the ratio between the maximal width of the frontal horns and the maximal width of the inner diameter of the cranium [ 7 ] as shown in Fig. 1 . Statistical analysis Statistical analyses were conducted using the Statistical Package for the Social Sciences (SPSS v. 25, IBM, SPSS for Windows, NY: IBM Corp.). Variables were investigated using visual and analytical methods (Kolmogorov–Smirnov test) to determine whether they were normally distributed. Mean, median, standart deviasion, minimum and maximum values and percentile of fetal evans index were assessed using descriptive data, histograms and box plots. Results Demographic data of the study group shown in the Table 1 . In the total sample, Evans index ranged between 0.10 and 0.48, and the mean value was 0.2590 (SD ± 0.354) (Table 2). The mean values of Evans index were 0.2590, 0.2810, 0.2586, 0.2648, 0.2540, and 0.2570 for groups 0 to 5, respectively. The distribution of Evans index at different gestational weeks is shown in Fig. 2 . Discussion We examined a large sample systematically to obtain reference values and descriptive data for fetal Evans index during the prenatal period. Previous studies have used smaller samples or non-representative populations, and normal values have not been definitively established in the adult population [ 8 – 10 ]. Normal values of Evans index during the fetal period have not been reported using population data before. Clinicians and researchers will benefit from being aware of the range of values for Evans index at different gestational weeks during the fetal period, as this value could contribute to counselling the families regarding the prognosis of this process. In a study by Jarah et al., average values ≥ 0.3 were found in elderly men, and the average Evans index was found to be 0.31 in individuals with dementia. In the same study, among those showing radiological signs of iNPH, the average value of Evans index was found to be above the 95th percentile for the total sample, and the average value for individuals without dementia, iNPH, stroke, Parkinson's disease, or schizophrenia was determined to be 0.27. The study also emphasizes that it is difficult to determine a clear threshold value for the diagnosis of iNPH based on existing data, and it is unknown whether individuals with symptoms of iNPH and Evans index < 0.3 will respond to treatment[ 6 ]. According to previous reports, ventricular size was not found to be associated with the outcome after shunt surgery, and none of the parameters, including drainage volume, ventricular volume, absolute and relative changes in ventricular volume, and drainage/ventricular volume ratio, showed differences between patients who improved and those who did not in terms of cognitive and motor functions [ 11 ]. In such a case, it may not be meaningful to identify a defined cut-off value for Evans index, and instead, more advanced imaging such as volumetric analysis of CSF spaces may have greater value. Additionally, the Z-Evans index (a sign of dilation of the anterior horn in the lower/upper dimension) is suggested as a useful alternative [ 12 ]. We can indirectly evaluate the dilation of the ventricular system by calculating the Evans index, which is calculated by the ratio of the width of the anterior horns of the lateral ventricles to the distance between two parietal bones. INPH guidelines define Evans index values > 0.3 as ventricular enlargement [ 13 ]. Normal pressure hydrocephalus (NPH) is a treatable condition that is often underdiagnosed. The Evans index has been primarily calculated in cases of NPH and imaging methods such as magnetic resonance imaging (MRI) and computed tomography (CT) are commonly used. Although MRI is used to evaluate brain development, examine ventricular size, and predict hydrocephalus in intrauterine life, the utility of this method is debatable in terms of both cost and feasibility[ 2 , 14 ]. During routine prenatal examinations, ultrasound (USG) is the most commonly used method to assess intrauterine growth. Calculating estimated brain volume and ventricular size using USG is a simple and practical method. Our clinic has high-quality USG devices and expert clinicians in the field. Graca et al. compared estimated brain volume in 72 preterm infants at term and 56 control term infants without major cerebral lesions using cranial ultrasound (crUS). They found that the groups had similar estimated intracranial volumes, but preterm infants had larger estimated extracerebral area, lateral ventricular coronal area, and total optic disc-to-disc (TOD) values, and smaller cerebral volume (p < 0.001). The authors reported that even in the absence of large cerebral lesions, preterm infants had decreased average extrauterine cerebral growth [ 15 ]. Maunu and his friends evaluated the relationships between the width of the lateral ventricles' frontal and occipital horns, the ventricular brain ratio measured by cranial ultrasound (crUS), the total and regional brain volumes measured by MRI, and the head circumference at term age in a study conducted on 209 VLBW (< 1500 g) premature infants. They found that abnormal ventricular brain ratio (0.35), enlarged ventricular horns, and smaller head circumference were significantly associated with smaller total brain tissue volume [ 16 ]. In another study, Işık et al. attempted to estimate brain volume by calculating the relationship between BPD and the ventricle ratio in 482 preterm infants. The study concluded that a decrease in BPD/ventricle ratio was associated with cerebral pathologies even in the absence of severe intracranial hemorrhage and ventriculomegaly [ 17 ]. In the present study, we examined a large population of pregnant women who presented to the perinatology clinic at various gestational weeks and did not have any serious systemic illnesses according to our exclusion criteria. There is no study in the literature that has used such a large sample group to investigate the Evans index during the prenatal period. In this study, we aimed to calculate a nomogram for the Evans index in pregnant women without any detected fetal anomalies. We included measurements from different clinicians, increased the sample size, and expanded the screening weeks of the patients to obtain more accurate results. Ultrasound is the main, most practical, accessible and sensitive modality we use as maternal/fetal medicine specialists to assess fetal anatomy and well-being. Ventriculomegaly and hydrocephaly are findings we frequently encounter in our practice and have difficulty counselling in the absence of additional detected fetal abnormalities. The fetal Evans index may be a useful tool to predict the neonatal and early childhood outcomes with regard to need for surgery and we suggest this index be used to guide further studies. In our opinion, this novel index will give a more comprehensive assessment of the relationship between fetal ventricules and the fetal head. Thus, this measurement including the proportion of the venticules to the fetal head will provide more valuable information compared to just measuring the width of the ventricules in the prediction of prognosis. Conclusion In conclusion, the determination of a nomogram for fetal Evans index may help physicians to objectively evaluate fetal ventriculomegaly cases in the future. However, studies focusing on the utility of Evans index in the fetal ventriculomegaly cases are necessary to make more precise conclusions. Abbreviations Evans Index MWFH/MID MWFH maximal width of the frontal horn MID maximum inner diameter mm millimeter n number SD standard deviasion. Declarations Funding No funding. Data Availability The data that support the finding of this study are not openly available duo to reasons of sensitivity anda re available from the corresponding author upon reasonable request. Ethical approval The study adhered to the principles of the Declaration of Helsinki and was approved by the Human Ethics Committee of the hospital (number: E2-23-5678). Consent to participate Informed consent was obtained from all individual pregnant participants included in the study Author Contributions Design : Dilek Şahin, Özgür Kara, Harun Demirci, Atakan Tanaçan, Bedri Sakcak; Planning : Dilek Şahin, Harun Demirci, Atakan Tanaçan, Özgür Kara, Petek Feriha Uzuner, Bedri Sakcak, Ramazan Denizli, Nihat Farisoğulları, Sadık Orhun Aktaş, Osman Onur Özkavak ; Conduct : Dilek Şahin, Özgür Kara, Petek Feriha Uzuner, Nihat Farisoğulları, Sadık Orhun Aktaş, Osman Onur Özkavak, Bedri Sakcak; Data analysis : Dilek Şahin, Bedri Sakcak, Atakan Tanaçan, Özgür Kara, Harun Demirci, Petek Feriha Uzuner, Sadık Orhun Aktaş, Nihat Farisoğulları, Osman Onur Özkavak, Ramazan Denizli; Manuscript writing : Bedri Sakcak, Harun Demirci, Petek Feriha Uzuner, Sadık Orhun Aktaş, Ramazan Denizli, Nihat Farisoğulları, Atakan Tanaçan, Osman Onur Özkavak. Conflict of Interest The authors have no relevant financial or non-finacial interests to disclose. The authors declare that they have no conflict of interest. References Evans WA (1942) An encephalographic ratio for estimating ventricular enlargement and cerebral atrophy. Archives Neurol Psychiatry 47(6):931–937 Ambarki K, Israelsson H, Wåhlin A, Birgander R, Eklund A, Malm J (2010) Brain ventricular size in healthy elderly: comparison between Evans index and volume measurement. Neurosurgery 67(1):94–99 He W, Fang X, Wang X, Gao P, Gao X, Zhou X et al (2020) A new index for assessing cerebral ventricular volume in idiopathic normal-pressure hydrocephalus: a comparison with Evans’ index. Neuroradiology 62:661–667 Adams R, Fisher C, Hakim S, Ojemann R, Sweet W (1965) Symptomatic occult hydrocephalus with normal cerebrospinal-fluid pressure: a treatable syndrome. N Engl J Med 273(3):117–126 Andrén K, Wikkelsø C, Tisell M, Hellström P (2014) Natural course of idiopathic normal pressure hydrocephalus. J Neurol Neurosurg Psychiatry 85(7):806–810 Jaraj D, Rabiei K, Marlow T, Jensen C, Skoog I, Wikkelsø C (2017) Estimated ventricle size using Evans index: reference values from a population-based sample. Eur J Neurol 24(3):468–474 Zhou X, Xia J (2022) Application of Evans index in normal pressure hydrocephalus patients: a mini review. Front Aging Neurosci 13:783092 Toma AK, Holl E, Kitchen ND, Watkins LD (2011) Evans' index revisited: the need for an alternative in normal pressure hydrocephalus. Neurosurgery 68(4):939–944 Ishii K, Kanda T, Harada A, Miyamoto N, Kawaguchi T, Shimada K et al (2008) Clinical impact of the callosal angle in the diagnosis of idiopathic normal pressure hydrocephalus. Eur Radiol 18:2678–2683 Inatomi Y, Yonehara T, Hashimoto Y, Hirano T, Uchino M (2008) Correlation between ventricular enlargement and white matter changes. J Neurol Sci 269(1–2):12–17 Lenfeldt N, Hansson W, Larsson A, Birgander R, Eklund A, Malm J (2012) Three-day CSF drainage barely reduces ventricular size in normal pressure hydrocephalus. Neurology 79(3):237–242 Yamada S, Ishikawa M, Yamamoto K (2015) Optimal diagnostic indices for idiopathic normal pressure hydrocephalus based on the 3D quantitative volumetric analysis for the cerebral ventricle and subarachnoid space. Am J Neuroradiol 36(12):2262–2269 Relkin N, Marmarou A, Klinge P, Bergsneider M, Black PM (2005) Diagnosing idiopathic normal-pressure hydrocephalus. Neurosurgery 57(3 Suppl). 10.1227/01.neu.0000168185.29659.c5 PubMed PMID: 16160425 S4-16; discussion ii-v Inder TE, Warfield SK, Wang H, Huppi PS, Volpe JJ (2005) Abnormal cerebral structure is present at term in premature infants. Pediatrics 115(2):286–294 Graca AM, Cardoso KRV, da Costa JMFP, Cowan FM (2013) Cerebral volume at term age: comparison between preterm and term-born infants using cranial ultrasound. Early Hum Dev 89(9):643–648 Maunu J, Parkkola R, Rikalainen H, Lehtonen L, Haataja L, Lapinleimu H et al (2009) Brain and ventricles in very low birth weight infants at term: a comparison among head circumference, ultrasound, and magnetic resonance imaging. Pediatrics 123(2):617–626 Işık Ş, Büyüktiryaki M, Şimşek GK, Kutman HGK, Canpolat FE (2021) Relationship between biparietal diameter/ventricular ratio and neurodevelopmental outcomes in non-handicapped very preterm infants. Child's Nerv Syst 37:1121–1126 Tables Table 1. Demographic data of the study groups n=894 Maternal age (year) 29.4 ±11.4 Gestational week 33.3 ±4.5 BMI (kg/m 2 ) 28.2 ±4.59 Abbreviations:BMI,body mass index; n,number. Tables 2: Evans Index values in the study group (n=894) Evans Index MWFH(mm) MID(mm) Mean .2590 20.47 80.12 median .2545 20.80 81.95 SD .03544 3.04 21.22 Minimum .10 10.0 17.60 Maximum .48 40 99.30 Percentile 5 .2182 14.8 59.95 Percentile 25 .2415 18.5 74.20 Percentile 50 .2545 20.80 81.95 Percentile 75 .2733 22.30 87.52 Percentile 95 .3047 24.82 92.00 Abbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number ; SD,standard deviasion. Table 3: Evans Index values in the group 0 (16-20 gestational week) (n=10) Evans Index MWFH(mm) MID(mm) Mean .2590 14.24 47.270 median .2545 14.30 44.050 SD .03544 1.679 13.95 Minimum .3 11.50 29.0 Maximum .48 17.80 78.80 Percentile 5 .2182 11.50 29 Percentile 25 .2415 13.30 38.1 Percentile 50 .2545 14.30 44.050 Percentile 75 .2733 14.90 56.90 Percentile 95 .3047 - - Abbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion. Table 4: Evans Index values in the group 1 (21-24 gestational week) (n=37) Evans Index MWFH(mm) MID(mm) Mean .2810 15.32 56.51 median .2742 14.40 55.30 SD .09042 3.058 12.16 Minimum .22 10.0 17.6 Maximum .48 22.60 90.40 Percentile 5 .2179 10.27 41.36 Percentile 25 .2388 13.85 48.95 Percentile 50 .2742 14.40 55.30 Percentile 75 .2855 16.40 62.90 Percentile 95 .3538 21.07 74.11 Abbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion. Table 5: Evans Index values in the group 2 (25-28 gestational week) (n=110) Evans Index MWFH(mm) MID(mm) Mean .2586 17.28 67.00 median .2557 17.30 67.20 SD .02789 2.107 6.277 Minimum .21 13.70 50.90 Maximum .38 26.80 96.80 Percentile 5 .2195 14.30 56.16 Percentile 25 .2396 15.37 63.22 Percentile 50 .2557 17.30 67.20 Percentile 75 .2729 18.32 70.20 Percentile 95 .3081 20.80 76.09 Abbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion. Table 6: Evans Index values in the group 3 (29-32 gestational week) (n=149) Evans Index MWFH(mm) MID(mm) Mean .2648 20.18 79.72 median .2700 20.20 76.00 SD .03969 2.706 45.53 Minimum .03 14.96 54.4 Maximum .44 40.0 88,20 Percentile 5 .2171 16.2 68.2 Percentile 25 .2427 18.4 72.3 Percentile 50 .2700 20.20 76.00 Percentile 75 .2849 21.50 79.10 Percentile 95 .3072 23.70 85.65 Abbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion. Table 7: Evans Index values in the group 4 ( 33-36 gestational week) (n=350) Evans Index MWFH(mm) MID(mm) Mean .2540 20.95 82.69 median .2512 21.00 83.45 SD .022402 1.96 5.69 Minimum .19 14 50 Maximum .35 30.40 99.3 Percentile 5 .2168 17.75 73.7 Percentile 25 .2404 20.00 79 Percentile 50 .2512 21.00 83.45 Percentile 75 .2645 22.20 86.30 Percentile 95 .2950 24.00 90.24 Abbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion. Table 8: Evans Index values in the group 5 (37-40 gestational week) (n=238) Evans Index MWFH(mm) MID(mm) Mean .2570 22.49 87.70 median .2528 22.50 88.90 SD .02836 2.455 5.25 Minimum .18 14.70 60.20 Maximum .44 39.80 98.00 Percentile 5 .2195 18.39 80.57 Percentile 25 .2418 21.18 85.07 Percentile 50 .2528 22.50 88.90 Percentile 75 .2708 24.00 91.52 Percentile 95 .3015 25.52 94.10 Abbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3963802","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":274859486,"identity":"b93759c1-7711-404e-9c6d-5f51befc82dd","order_by":0,"name":"Bedri 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of Evans Index at Different Gestational Weeks\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3963802/v1/30c26ad426afe7c7c6230613.jpeg"},{"id":52384779,"identity":"df07e9ac-3bc5-4510-b9ff-1d3cb1ec9a39","added_by":"auto","created_at":"2024-03-10 20:25:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":398497,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3963802/v1/a6b7c648-26a6-4662-b650-6013c528fbbe.pdf"}],"financialInterests":"","formattedTitle":"Development of a Nomogram for Fetal Evans Index","fulltext":[{"header":"What does this study adds to the clinical work?","content":"\u003cp\u003e-The identification of a nomogram for the fetal Evans index.\u003c/p\u003e\n\u003cp\u003e-Fetal Evans index may help future physicians to objectively evaluate cases of fetal ventriculomegaly and/or hydrocephaly.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eThe Evans Index (EI) is defined as the ratio of the maximum width of the anterior horns of the lateral ventricles to the maximum inner diameter of the cranium. It was first proposed by Evans in 1942 and has been used to indirectly evaluate the dilation of the ventricular system[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Several retrospective studies analyzing normal patients at various centers have emphasized that the ratio of the transverse diameter of the anterior horns of the lateral ventricles to the inner diameter of the cranium can be used as an index to evaluate ventricular size. The study concluded that this ratio is within normal limits between 0.2\u0026ndash;0.25, represents early or suspected dilation between 0.25\u0026ndash;0.30, and values above 0.30 definitively indicate abnormal ventricular dilation [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eNormal pressure hydrocephalus (NPH) is a clinical condition characterized by cognitive impairment, gait disturbance, and urinary incontinence, along with ventricular enlargement, despite normal cerebrospinal fluid (CSF) pressure. It was first described by Dr. Adams and colleagues in 1965 [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. NPH is a treatable condition but often goes undiagnosed. Early diagnosis and treatment of NPH is crucial as this can increase the likelihood of a favorable outcome. However, knowledge regarding the utility of this novel index in the fetus is limited and new studies are necessary to determine the reference values of Evans index in the fetal life [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe Evans index plays a crucial role in diagnosing iNPH (Idiopathic Normal Pressure Hydrocephalus). However, there is a lack of previous epidemiological studies on the values of this index in fetal life. The main purpose of this study is to obtain reference values for the Evans index in normal fetuses from various gestational weeks during the prenatal period and to create a nomogram.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cp\u003eThis prospective cohort study was conducted at the Perinatology Clinic of the Obstetrics and Gynecology Department of the Turkish Ministry of Health Ankara City Hospital between March 02, 2022, and June 30,2023. The study adhered to the principles of the Declaration of Helsinki and was approved by the Human Ethics Committee of the hospital (number: E2-23-5678). Written informed consent was obtained from all 894 pregnant women at 16\u0026ndash;40 weeks of gestation who presented to the perinatology clinic of the hospital between March 2022 and June 2023. Patients with systemic diseases such as kidney disease, diabetes, and hypertension, women with multiple pregnancies, smokers, those with elevated glucose tolerance values, oligohydramnios or polyhydramnios and fetal growth restriction,fetal microcephaly or macrocephaly, fetuses with chromosomal or structural fetal anomalies were excluded from the study. The pregnant women were divided into six groups based on their gestational week: group 0 (16\u0026ndash;20), group 1 (21\u0026ndash;24), group 2 (25\u0026ndash;28), group 3 (29\u0026ndash;32), group 4 (33\u0026ndash;36), and group 5 (37\u0026ndash;40). We calculated the indices of each group separately, including the Evans index (mean, median, standard deviation, minimum, maximum, percentile). The patients' descriptive data, such as age, gestational weeks, and body mass index (BMI), were also noted.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eUltrasonography\u003c/h2\u003e \u003cp\u003eMeasurements were conducted using the Voluson S10 ultrasonography device (GE Medical Systems) with a 3.5 MHz convex transducer (6C1-PVT-375BT) transabdominal probe by the same observer (BS) under the supervision of an experienced Professor of maternal fetal medicine (DS). The ultrasound images consisted of transverse sections, following previously described radiologic evaluations. The Evans index was calculated as the ratio between the maximal width of the frontal horns and the maximal width of the inner diameter of the cranium [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eStatistical analyses were conducted using the Statistical Package for the Social Sciences (SPSS v. 25, IBM, SPSS for Windows, NY: IBM Corp.). Variables were investigated using visual and analytical methods (Kolmogorov\u0026ndash;Smirnov test) to determine whether they were normally distributed. Mean, median, standart deviasion, minimum and maximum values and percentile of fetal evans index were assessed using descriptive data, histograms and box plots.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eDemographic data of the study group shown in the Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. In the total sample, Evans index ranged between 0.10 and 0.48, and the mean value was 0.2590 (SD\u0026thinsp;\u0026plusmn;\u0026thinsp;0.354) (Table\u0026nbsp;2).\u003c/p\u003e \u003cp\u003eThe mean values of Evans index were 0.2590, 0.2810, 0.2586, 0.2648, 0.2540, and 0.2570 for groups 0 to 5, respectively.\u003c/p\u003e \u003cp\u003eThe distribution of Evans index at different gestational weeks is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWe examined a large sample systematically to obtain reference values and descriptive data for fetal Evans index during the prenatal period. Previous studies have used smaller samples or non-representative populations, and normal values have not been definitively established in the adult population [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Normal values of Evans index during the fetal period have not been reported using population data before. Clinicians and researchers will benefit from being aware of the range of values for Evans index at different gestational weeks during the fetal period, as this value could contribute to counselling the families regarding the prognosis of this process.\u003c/p\u003e \u003cp\u003eIn a study by Jarah et al., average values\u0026thinsp;\u0026ge;\u0026thinsp;0.3 were found in elderly men, and the average Evans index was found to be 0.31 in individuals with dementia. In the same study, among those showing radiological signs of iNPH, the average value of Evans index was found to be above the 95th percentile for the total sample, and the average value for individuals without dementia, iNPH, stroke, Parkinson's disease, or schizophrenia was determined to be 0.27. The study also emphasizes that it is difficult to determine a clear threshold value for the diagnosis of iNPH based on existing data, and it is unknown whether individuals with symptoms of iNPH and Evans index\u0026thinsp;\u0026lt;\u0026thinsp;0.3 will respond to treatment[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAccording to previous reports, ventricular size was not found to be associated with the outcome after shunt surgery, and none of the parameters, including drainage volume, ventricular volume, absolute and relative changes in ventricular volume, and drainage/ventricular volume ratio, showed differences between patients who improved and those who did not in terms of cognitive and motor functions [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. In such a case, it may not be meaningful to identify a defined cut-off value for Evans index, and instead, more advanced imaging such as volumetric analysis of CSF spaces may have greater value. Additionally, the Z-Evans index (a sign of dilation of the anterior horn in the lower/upper dimension) is suggested as a useful alternative [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWe can indirectly evaluate the dilation of the ventricular system by calculating the Evans index, which is calculated by the ratio of the width of the anterior horns of the lateral ventricles to the distance between two parietal bones. INPH guidelines define Evans index values\u0026thinsp;\u0026gt;\u0026thinsp;0.3 as ventricular enlargement [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eNormal pressure hydrocephalus (NPH) is a treatable condition that is often underdiagnosed. The Evans index has been primarily calculated in cases of NPH and imaging methods such as magnetic resonance imaging (MRI) and computed tomography (CT) are commonly used. Although MRI is used to evaluate brain development, examine ventricular size, and predict hydrocephalus in intrauterine life, the utility of this method is debatable in terms of both cost and feasibility[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDuring routine prenatal examinations, ultrasound (USG) is the most commonly used method to assess intrauterine growth. Calculating estimated brain volume and ventricular size using USG is a simple and practical method. Our clinic has high-quality USG devices and expert clinicians in the field.\u003c/p\u003e \u003cp\u003eGraca et al. compared estimated brain volume in 72 preterm infants at term and 56 control term infants without major cerebral lesions using cranial ultrasound (crUS). They found that the groups had similar estimated intracranial volumes, but preterm infants had larger estimated extracerebral area, lateral ventricular coronal area, and total optic disc-to-disc (TOD) values, and smaller cerebral volume (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The authors reported that even in the absence of large cerebral lesions, preterm infants had decreased average extrauterine cerebral growth [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMaunu and his friends evaluated the relationships between the width of the lateral ventricles' frontal and occipital horns, the ventricular brain ratio measured by cranial ultrasound (crUS), the total and regional brain volumes measured by MRI, and the head circumference at term age in a study conducted on 209 VLBW (\u0026lt;\u0026thinsp;1500 g) premature infants. They found that abnormal ventricular brain ratio (0.35), enlarged ventricular horns, and smaller head circumference were significantly associated with smaller total brain tissue volume [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn another study, Işık et al. attempted to estimate brain volume by calculating the relationship between BPD and the ventricle ratio in 482 preterm infants. The study concluded that a decrease in BPD/ventricle ratio was associated with cerebral pathologies even in the absence of severe intracranial hemorrhage and ventriculomegaly [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn the present study, we examined a large population of pregnant women who presented to the perinatology clinic at various gestational weeks and did not have any serious systemic illnesses according to our exclusion criteria. There is no study in the literature that has used such a large sample group to investigate the Evans index during the prenatal period. In this study, we aimed to calculate a nomogram for the Evans index in pregnant women without any detected fetal anomalies. We included measurements from different clinicians, increased the sample size, and expanded the screening weeks of the patients to obtain more accurate results.\u003c/p\u003e \u003cp\u003eUltrasound is the main, most practical, accessible and sensitive modality we use as maternal/fetal medicine specialists to assess fetal anatomy and well-being. Ventriculomegaly and hydrocephaly are findings we frequently encounter in our practice and have difficulty counselling in the absence of additional detected fetal abnormalities. The fetal Evans index may be a useful tool to predict the neonatal and early childhood outcomes with regard to need for surgery and we suggest this index be used to guide further studies. In our opinion, this novel index will give a more comprehensive assessment of the relationship between fetal ventricules and the fetal head. Thus, this measurement including the proportion of the venticules to the fetal head will provide more valuable information compared to just measuring the width of the ventricules in the prediction of prognosis.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, the determination of a nomogram for fetal Evans index may help physicians to objectively evaluate fetal ventriculomegaly cases in the future. However, studies focusing on the utility of Evans index in the fetal ventriculomegaly cases are necessary to make more precise conclusions.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eEvans Index\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMWFH/MID\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMWFH\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003emaximal width of the frontal horn\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMID\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003emaximum inner diameter\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003emm\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003emillimeter\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003en\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003enumber\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSD\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003estandard deviasion.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003eNo funding.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u003c/strong\u003e The data that support the finding of this study are not openly available duo to reasons of sensitivity anda re available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval\u003c/strong\u003e The study adhered to the principles of the Declaration of Helsinki and was approved by the Human Ethics Committee of the hospital (number: E2-23-5678).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e Informed consent was obtained from all individual pregnant participants included in the study\u0026nbsp;\u003c/p\u003e\u003ch2\u003eAuthor Contributions\u003c/h2\u003e \u003cp\u003e \u003cb\u003eDesign\u003c/b\u003e: Dilek Şahin, \u0026Ouml;zg\u0026uuml;r Kara, Harun Demirci, Atakan Tana\u0026ccedil;an, Bedri Sakcak; \u003cb\u003ePlanning\u003c/b\u003e: Dilek Şahin, Harun Demirci, Atakan Tana\u0026ccedil;an, \u0026Ouml;zg\u0026uuml;r Kara, Petek Feriha Uzuner, Bedri Sakcak, Ramazan Denizli, Nihat Farisoğulları, Sadık Orhun Aktaş, Osman Onur \u0026Ouml;zkavak ; \u003cb\u003eConduct\u003c/b\u003e: Dilek Şahin, \u0026Ouml;zg\u0026uuml;r Kara, Petek Feriha Uzuner, Nihat Farisoğulları, Sadık Orhun Aktaş, Osman Onur \u0026Ouml;zkavak, Bedri Sakcak; \u003cb\u003eData analysis\u003c/b\u003e: Dilek Şahin, Bedri Sakcak, Atakan Tana\u0026ccedil;an, \u0026Ouml;zg\u0026uuml;r Kara, Harun Demirci, Petek Feriha Uzuner, Sadık Orhun Aktaş, Nihat Farisoğulları, Osman Onur \u0026Ouml;zkavak, Ramazan Denizli; \u003cb\u003eManuscript writing\u003c/b\u003e: Bedri Sakcak, Harun Demirci, Petek Feriha Uzuner, Sadık Orhun Aktaş, Ramazan Denizli, Nihat Farisoğulları, Atakan Tana\u0026ccedil;an, Osman Onur \u0026Ouml;zkavak.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-finacial interests to disclose. The authors declare that they have no conflict of interest.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eEvans WA (1942) An encephalographic ratio for estimating ventricular enlargement and cerebral atrophy. Archives Neurol Psychiatry 47(6):931\u0026ndash;937\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAmbarki K, Israelsson H, W\u0026aring;hlin A, Birgander R, Eklund A, Malm J (2010) Brain ventricular size in healthy elderly: comparison between Evans index and volume measurement. Neurosurgery 67(1):94\u0026ndash;99\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHe W, Fang X, Wang X, Gao P, Gao X, Zhou X et al (2020) A new index for assessing cerebral ventricular volume in idiopathic normal-pressure hydrocephalus: a comparison with Evans\u0026rsquo; index. Neuroradiology 62:661\u0026ndash;667\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAdams R, Fisher C, Hakim S, Ojemann R, Sweet W (1965) Symptomatic occult hydrocephalus with normal cerebrospinal-fluid pressure: a treatable syndrome. N Engl J Med 273(3):117\u0026ndash;126\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAndr\u0026eacute;n K, Wikkels\u0026oslash; C, Tisell M, Hellstr\u0026ouml;m P (2014) Natural course of idiopathic normal pressure hydrocephalus. J Neurol Neurosurg Psychiatry 85(7):806\u0026ndash;810\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJaraj D, Rabiei K, Marlow T, Jensen C, Skoog I, Wikkels\u0026oslash; C (2017) Estimated ventricle size using Evans index: reference values from a population-based sample. Eur J Neurol 24(3):468\u0026ndash;474\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhou X, Xia J (2022) Application of Evans index in normal pressure hydrocephalus patients: a mini review. Front Aging Neurosci 13:783092\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eToma AK, Holl E, Kitchen ND, Watkins LD (2011) Evans' index revisited: the need for an alternative in normal pressure hydrocephalus. Neurosurgery 68(4):939\u0026ndash;944\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIshii K, Kanda T, Harada A, Miyamoto N, Kawaguchi T, Shimada K et al (2008) Clinical impact of the callosal angle in the diagnosis of idiopathic normal pressure hydrocephalus. Eur Radiol 18:2678\u0026ndash;2683\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eInatomi Y, Yonehara T, Hashimoto Y, Hirano T, Uchino M (2008) Correlation between ventricular enlargement and white matter changes. J Neurol Sci 269(1\u0026ndash;2):12\u0026ndash;17\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLenfeldt N, Hansson W, Larsson A, Birgander R, Eklund A, Malm J (2012) Three-day CSF drainage barely reduces ventricular size in normal pressure hydrocephalus. Neurology 79(3):237\u0026ndash;242\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYamada S, Ishikawa M, Yamamoto K (2015) Optimal diagnostic indices for idiopathic normal pressure hydrocephalus based on the 3D quantitative volumetric analysis for the cerebral ventricle and subarachnoid space. Am J Neuroradiol 36(12):2262\u0026ndash;2269\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRelkin N, Marmarou A, Klinge P, Bergsneider M, Black PM (2005) Diagnosing idiopathic normal-pressure hydrocephalus. Neurosurgery 57(3 Suppl). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1227/01.neu.0000168185.29659.c5\u003c/span\u003e\u003cspan address=\"10.1227/01.neu.0000168185.29659.c5\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003ePubMed PMID: 16160425 S4-16; discussion ii-v\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eInder TE, Warfield SK, Wang H, Huppi PS, Volpe JJ (2005) Abnormal cerebral structure is present at term in premature infants. Pediatrics 115(2):286\u0026ndash;294\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGraca AM, Cardoso KRV, da Costa JMFP, Cowan FM (2013) Cerebral volume at term age: comparison between preterm and term-born infants using cranial ultrasound. Early Hum Dev 89(9):643\u0026ndash;648\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaunu J, Parkkola R, Rikalainen H, Lehtonen L, Haataja L, Lapinleimu H et al (2009) Brain and ventricles in very low birth weight infants at term: a comparison among head circumference, ultrasound, and magnetic resonance imaging. Pediatrics 123(2):617\u0026ndash;626\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIşık Ş, B\u0026uuml;y\u0026uuml;ktiryaki M, Şimşek GK, Kutman HGK, Canpolat FE (2021) Relationship between biparietal diameter/ventricular ratio and neurodevelopmental outcomes in non-handicapped very preterm infants. Child's Nerv Syst 37:1121\u0026ndash;1126\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1.\u003c/strong\u003e Demographic data of the study groups\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003en=894\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003eMaternal age (year)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003e29.4 \u0026plusmn;11.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003eGestational week\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003e33.3 \u0026plusmn;4.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50%\" valign=\"top\"\u003e\n \u003cp\u003e28.2 \u0026plusmn;4.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:BMI,body mass index; n,number.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTables 2:\u0026nbsp;\u003c/strong\u003eEvans Index values in the study group\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e(n=894)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003eEvans Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003eMWFH(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003eMID(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2590\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e80.12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003emedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2545\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e81.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.03544\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e3.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e21.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMinimum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e10.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e17.60\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e99.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Percentile 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2182\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e59.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2415\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e18.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e74.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2545\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e81.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2733\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e22.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e87.52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.3047\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e24.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e92.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number ; SD,standard deviasion.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3:\u0026nbsp;\u003c/strong\u003eEvans Index values in the group 0 (16-20 gestational week)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e(n=10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003eEvans Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003eMWFH(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003eMID(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2590\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e47.270\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003emedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2545\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e44.050\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.03544\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e1.679\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e13.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMinimum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e11.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e29.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e17.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e78.80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Percentile 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2182\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e11.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2415\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e13.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e38.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2545\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e44.050\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2733\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e56.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.3047\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4:\u0026nbsp;\u003c/strong\u003eEvans Index values in the group 1 (21-24 gestational week)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e(n=37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003eEvans Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003eMWFH(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003eMID(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2810\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e15.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e56.51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003emedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2742\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e55.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.09042\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e3.058\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e12.16\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMinimum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e10.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e17.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e22.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e90.40\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Percentile 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2179\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e10.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e41.36\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2388\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e13.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e48.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2742\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e55.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2855\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e16.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e62.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.3538\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e21.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e74.11\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5:\u0026nbsp;\u003c/strong\u003eEvans Index values in the group 2 (25-28 gestational week)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e(n=110)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003eEvans Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003eMWFH(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003eMID(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2586\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e17.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e67.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003emedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2557\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e17.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e67.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.02789\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e2.107\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e6.277\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMinimum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e13.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e50.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e26.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e96.80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Percentile 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2195\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e56.16\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2396\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e15.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e63.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2557\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e17.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e67.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2729\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e18.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e70.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.3081\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e76.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6:\u0026nbsp;\u003c/strong\u003eEvans Index values in the group 3 (29-32 gestational week)\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e(n=149)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003eEvans Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003eMWFH(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003eMID(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2648\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e79.72\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003emedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2700\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e76.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.03969\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e2.706\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e45.53\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMinimum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e54.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e40.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e88,20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Percentile 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2171\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e16.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e68.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2427\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e18.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e72.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2700\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e76.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2849\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e21.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e79.10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.3072\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e23.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e85.65\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 7:\u0026nbsp;\u003c/strong\u003eEvans Index values in the group 4 ( 33-36 gestational week)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e(n=350)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003eEvans Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003eMWFH(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003eMID(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2540\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e82.69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003emedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2512\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e21.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e83.45\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.022402\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e1.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e5.69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMinimum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e50\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e30.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e99.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Percentile 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2168\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e17.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e73.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2404\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e20.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e79\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2512\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e21.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e83.45\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2645\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e22.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e86.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2950\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e24.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e90.24\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 8:\u0026nbsp;\u003c/strong\u003eEvans Index values in the group 5 (37-40 gestational week)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e(n=238)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003eEvans Index\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003eMWFH(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003eMID(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2570\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e22.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e87.70\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003emedian\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2528\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e22.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e88.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.02836\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e2.455\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e5.25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMinimum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e14.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e60.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e39.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e98.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Percentile 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2195\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e18.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e80.57\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2418\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e21.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e85.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2528\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e22.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e88.90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.2708\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e24.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e91.52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25.690021231422506%\" valign=\"top\"\u003e\n \u003cp\u003ePercentile 95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"23.56687898089172%\" valign=\"top\"\u003e\n \u003cp\u003e.3015\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.237791932059448%\" valign=\"top\"\u003e\n \u003cp\u003e25.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.505307855626327%\" valign=\"top\"\u003e\n \u003cp\u003e94.10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations:Evans Index,MWFH/MID; MWFH, maximal width of the frontal horn; MID,maximum inner diameter; mm,millimeter; n,number; SD,standard deviasion.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Evans Index, fetal ultrasound, nomogram","lastPublishedDoi":"10.21203/rs.3.rs-3963802/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3963802/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eThis study aims to investigate the fetal Evans Index and establish a nomogram for fetuses without any additional fetal anomalies detected during the prenatal period.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe conducted our research at Ankara City Hospital, including 894 patients who were admitted and evaluated between gestational weeks 16\u0026ndash;40. These patients had no fetal anomalies detected in subsequent gestational weeks. Descriptive data, such as age, gravidity, parity, and body mass index (BMI), were recorded. Gestational week and Evans Index (mean, median, standard deviation, minimum, maximum, percentile) were also documented. The Evans index was calculated as the ratio between the maximal width of the frontal horns and the maximal width of the inner diameter of the cranium.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eWe evaluated 894 fetuses in pregnant women had no fetal anomalies detected throughout the pregnancy. The evaluation took place at different gestational weeks, and a nomogram for the Evans Index was created.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eIt is relevant for clinicians and researchers to be aware of the range of fetal Evans Index values across different gestational weeks as a prognostic criterion.\u003c/p\u003e","manuscriptTitle":"Development of a Nomogram for Fetal Evans Index","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-28 20:27:01","doi":"10.21203/rs.3.rs-3963802/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"fa9e5c49-4434-4fa1-aeee-6c520c5a4e7c","owner":[],"postedDate":"February 28th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-03-10T20:17:15+00:00","versionOfRecord":[],"versionCreatedAt":"2024-02-28 20:27:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3963802","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3963802","identity":"rs-3963802","version":["v1"]},"buildId":"cBFmMYwuxLRRLfASyISRj","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}