{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T00:47:20Z","timestamp":1792025240712,"version":"4.4.0"},"reference-count":82,"publisher":"Springer Science and Business Media LLC","issue":"11","license":[{"start":{"date-parts":[[2026,6,6]],"date-time":"2026-06-06T00:00:00Z","timestamp":1780704000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,6]],"date-time":"2026-06-06T00:00:00Z","timestamp":1780704000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Pediatr Radiol"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Benign enlargement of the subarachnoid space (BESS) is a condition characterized by widened subarachnoid spaces, typically associated with macrocephaly or increasing head circumference during infancy or early childhood. Often described as idiopathic and self-limiting, BESS has also\u00a0been associated with developmental delays and spontaneous subdural collections. Yet, complete interrogation of these associations is limited by lack of normative subarachnoid space characterization and standardized diagnostic criteria.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>This project aimed to review and synthesize literature on imaging criteria and subarachnoid space measurements for BESS in infants and young children.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and methods<\/jats:title>\n                    <jats:p>A systematic PubMed search was conducted using BESS-related terminology, informed by preliminary findings from a manual snowball review. We limited results to reports that provided subarachnoid space measurements from computed tomography (CT), magnetic resonance imaging (MRI), or ultrasound (US) neuroimaging and investigated subjects with or without BESS and\/or macrocephaly from birth to 5\u00a0years old. Reports with concomitant neurological conditions affecting brain size were excluded.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The final collection included twenty-four reports (US\n                      <jats:italic>n<\/jats:italic>\n                      =10, CT\n                      <jats:italic>n<\/jats:italic>\n                      =6, MRI\n                      <jats:italic>n<\/jats:italic>\n                      =6, multiple\n                      <jats:italic>n<\/jats:italic>\n                      =2), consisting of 2,731 infants and children aged 0\u201336\u00a0months. Most reports evaluated non-BESS\/macrocephaly subjects (\n                      <jats:italic>n<\/jats:italic>\n                      =15), followed by BESS and\/or macrocephalic subjects (\n                      <jats:italic>n<\/jats:italic>\n                      =3) or both (\n                      <jats:italic>n<\/jats:italic>\n                      =6). Subarachnoid space measurements which were not expressly designated or were without detailed descriptions were the most commonly reported subarachnoid space index measure (\n                      <jats:italic>n<\/jats:italic>\n                      =14), followed by craniocortical width (CCW,\n                      <jats:italic>n<\/jats:italic>\n                      =9). Upper CCW measurements for non-BESS\/macrocephaly subjects in US reports ranged from 5 mm to 10.86\u00a0mm. In general, for each study that included both non-BESS\/macrocephaly and BESS and\/or macrocephaly subjects, measurements reported were greater among BESS and\/or macrocephaly subjects. There was some evidence of overlapping measurements between the subjects, such as those of CCW measurements in US studies.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Overall, substantial variability was observed in imaging methodology and measurement thresholds. This review underscores the need for standardized diagnostic criteria to improve the consistency and reliability of BESS diagnosis.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00247-026-06640-z","type":"journal-article","created":{"date-parts":[[2026,6,6]],"date-time":"2026-06-06T09:15:22Z","timestamp":1780737322000},"page":"2549-2563","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Subarachnoid space in infancy and early childhood: a systematic review of measurements"],"prefix":"10.1007","volume":"56","author":[{"given":"Jennifer","family":"Xu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofia","family":"Valencia Osorio","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M. Katherine","family":"Henry","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susan","family":"Sotardi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joanne N.","family":"Wood","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jakob","family":"Seidlitz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aaron","family":"Alexander-Bloch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jamie","family":"Catalano","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara H.","family":"Chaiyachati","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,6]]},"reference":[{"key":"6640_CR1","doi-asserted-by":"crossref","first-page":"901","DOI":"10.1542\/peds.77.6.901","volume":"77","author":"LA Alvarez","year":"1986","unstructured":"Alvarez LA, Maytal J, Shinnar S (1986) Idiopathic external hydrocephalus: natural history and relationship to benign familial macrocephaly. Pediatr 77:901\u2013907","journal-title":"Pediatr"},{"key":"6640_CR2","doi-asserted-by":"crossref","unstructured":"al-Saedi SA, Lemke RP, Debooy VD, Casiro O (1996) Subarachnoid fluid collections: a cause of macrocrania in preterm infants. J Pediatr 128:234\u2013236","DOI":"10.1016\/S0022-3476(96)70396-7"},{"key":"6640_CR3","first-page":"140","volume":"12","author":"PL Carolan","year":"1985","unstructured":"Carolan PL, McLaurin RL, Towbin RB et al (1985) Benign extra-axial collections of infancy. Pediatr Neurosci 12:140\u2013144","journal-title":"Pediatr Neurosci"},{"key":"6640_CR4","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1148\/radiology.147.2.6601281","volume":"147","author":"PK Kleinman","year":"1983","unstructured":"Kleinman PK, Zito JL, Davidson RI, Raptopoulos V (1983) The subarachnoid spaces in children: normal variations in size. Radiology 147:455\u2013457","journal-title":"Radiology"},{"key":"6640_CR5","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1111\/j.1469-8749.1987.tb02133.x","volume":"29","author":"RE Nickel","year":"1987","unstructured":"Nickel RE, Gallenstein JS (1987) Developmental prognosis for infants with benign enlargement of the subarachnoid spaces. Dev Med Child Neurol 29:181\u2013186","journal-title":"Dev Med Child Neurol"},{"key":"6640_CR6","doi-asserted-by":"publisher","first-page":"417","DOI":"10.1007\/s10143-011-0327-4","volume":"34","author":"SM Zahl","year":"2011","unstructured":"Zahl SM, Egge A, Helseth E, Wester K (2011) Benign external hydrocephalus: a review, with emphasis on management. Neurosurg Rev 34:417\u2013432","journal-title":"Neurosurg Rev"},{"key":"6640_CR7","doi-asserted-by":"crossref","first-page":"447","DOI":"10.1177\/0883073820977998","volume":"36","author":"K Yu","year":"2021","unstructured":"Yu K, Yi M, Cui R, Gong T et al (2021) Computed tomography measurement and evaluation of the subarachnoid space over cerebral convexities in infants aged 1-24 months. J Child Neurol 36:447\u2013452","journal-title":"J Child Neurol"},{"key":"6640_CR8","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1016\/j.pediatrneurol.2017.04.018","volume":"73","author":"US Wiig","year":"2017","unstructured":"Wiig US, Zahl SM, Egge A et al (2017) Epidemiology of benign external hydrocephalus in Norway-a population-based study. Pediatr Neurol 73:36\u201341","journal-title":"Pediatr Neurol"},{"key":"6640_CR9","doi-asserted-by":"publisher","first-page":"418","DOI":"10.1007\/BF00588027","volume":"37","author":"P Prassopoulos","year":"1995","unstructured":"Prassopoulos P, Cavouras D, Golfinopoulos S, Nezi M (1995) The size of the intra- and extraventricular cerebrospinal fluid compartments in children with idiopathic benign widening of the frontal subarachnoid space. Neuroradiology 37:418\u2013421","journal-title":"Neuroradiology"},{"key":"6640_CR10","doi-asserted-by":"crossref","first-page":"380","DOI":"10.1016\/S0887-8994(01)00349-6","volume":"25","author":"WWM Lam","year":"2001","unstructured":"Lam WWM, Ai VHG, Wong V, Leong LLY (2001) Ultrasonographic measurement of subarachnoid space in normal infants and children. Pediatr Neurol 25:380\u2013384","journal-title":"Pediatr Neurol"},{"key":"6640_CR11","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1007\/s00381-018-4007-3","volume":"35","author":"LV Sainz","year":"2019","unstructured":"Sainz LV, Zipfel J, Kerscher SR, Weichselbaum A et al (2019) Cerebro-venous hypertension: a frequent cause of so-called \u201cexternal hydrocephalus\u201d in infants. Child Nerv Syst 35:251\u2013256","journal-title":"Child Nerv Syst"},{"key":"6640_CR12","first-page":"119","volume":"107","author":"LC Hellbusch","year":"2007","unstructured":"Hellbusch LC (2007) Benign extracerebral fluid collections in infancy: clinical presentation and long-term follow-up. J Neurosurg 107:119\u2013125","journal-title":"J Neurosurg"},{"key":"6640_CR13","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/S0387-7604(84)80060-1","volume":"6","author":"CF Barlow","year":"1984","unstructured":"Barlow CF (1984) CSF dynamics in hydrocephalus--with special attention to external hydrocephalus. Brain Dev 6:119\u2013127","journal-title":"Brain Dev"},{"key":"6640_CR14","doi-asserted-by":"publisher","first-page":"93","DOI":"10.1007\/BF00342987","volume":"21","author":"B Kendall","year":"1981","unstructured":"Kendall B, Holland I (1981) Benign communicating hydrocephalus in children. Neuroradiology 21:93\u201396","journal-title":"Neuroradiology"},{"key":"6640_CR15","doi-asserted-by":"crossref","first-page":"518","DOI":"10.1001\/archneur.1980.00500570066011","volume":"37","author":"RE Pettit","year":"1980","unstructured":"Pettit RE, Kilroy AW, Allen JH (1980) Macrocephaly with head growth parallel to normal growth pattern: neurological, developmental, and computerized tomography findings in full-term infants. Arch Neurol 37:518\u2013521","journal-title":"Arch Neurol"},{"key":"6640_CR16","doi-asserted-by":"crossref","first-page":"536","DOI":"10.3171\/2021.12.PEDS21436","volume":"29","author":"KG Holste","year":"2022","unstructured":"Holste KG, Wieland CM, Ibrahim M et al (2022) Subdural hematoma prevalence and long-term developmental outcomes in patients with benign expansion of the subarachnoid spaces. J Neurosurg Pediatr 29:536\u2013542","journal-title":"J Neurosurg Pediatr"},{"key":"6640_CR17","doi-asserted-by":"publisher","first-page":"245","DOI":"10.1007\/s00381-018-4016-2","volume":"35","author":"SM Zahl","year":"2019","unstructured":"Zahl SM, Egge A, Helseth E et al (2019) Quality of life and physician-reported developmental, cognitive, and social problems in children with benign external hydrocephalus-long-term follow-up. Childs Nerv Syst 35:245\u2013250","journal-title":"Childs Nerv Syst"},{"key":"6640_CR18","doi-asserted-by":"crossref","first-page":"678","DOI":"10.1177\/088307389901401010","volume":"14","author":"G Alper","year":"1999","unstructured":"Alper G, Ekinci G, Yilmaz Y et al (1999) Magnetic resonance imaging characteristics of benign macrocephaly in children. J Child Neurol 14:678\u2013682","journal-title":"J Child Neurol"},{"key":"6640_CR19","doi-asserted-by":"crossref","first-page":"e973","DOI":"10.1016\/j.wneu.2022.05.079","volume":"164","author":"M Alshareef","year":"2022","unstructured":"Alshareef M, Tyler M, Litts C et al (2022) Prevalence of visible subdural spaces in benign enlargement of subarachnoid spaces in infancy: a retrospective analysis utilizing magnetic resonance imaging. World Neurosurg 164:e973\u2013e979","journal-title":"World Neurosurg"},{"key":"6640_CR20","doi-asserted-by":"crossref","first-page":"897","DOI":"10.1177\/0009922811406435","volume":"50","author":"PS Ghosh","year":"2011","unstructured":"Ghosh PS, Ghosh D (2011) Subdural hematoma in infants without accidental or nonaccidental injury: benign external hydrocephalus, a risk factor. Clin Pediatr (Phila) 50:897\u2013903","journal-title":"Clin Pediatr (Phila)"},{"key":"6640_CR21","doi-asserted-by":"crossref","first-page":"2373","DOI":"10.3174\/ajnr.A3588","volume":"34","author":"MV Greiner","year":"2013","unstructured":"Greiner MV, Richards TJ, Care MM, Leach JL (2013) Prevalence of subdural collections in children with macrocrania. AJNR Am J Neuroradiol 34:2373\u20132378","journal-title":"AJNR Am J Neuroradiol"},{"key":"6640_CR22","doi-asserted-by":"crossref","first-page":"31","DOI":"10.3171\/2017.7.PEDS17317","volume":"21","author":"JB Hansen","year":"2018","unstructured":"Hansen JB, Frazier T, Moffatt M et al (2018) Evaluations for abuse in young children with subdural hemorrhages: findings based on symptom severity and benign enlargement of the subarachnoid spaces. J Neurosurg Pediatr 21:31\u201337","journal-title":"J Neurosurg Pediatr"},{"key":"6640_CR23","doi-asserted-by":"crossref","unstructured":"Haws ME, Linscott L, Thomas C et al (2017) A retrospective analysis of the utility of head computed tomography and\/or magnetic resonance imaging in the management of benign macrocrania. J Pediatr 182:283-289.e281","DOI":"10.1016\/j.jpeds.2016.11.033"},{"key":"6640_CR24","doi-asserted-by":"crossref","unstructured":"Laubscher B, Deonna T, Uske A, van Melle G (1990) Primitive megalencephaly in children: natural history, medium term prognosis with special reference to external hydrocephalus. Eur J Pediatr 149:502\u2013507","DOI":"10.1007\/BF01959405"},{"key":"6640_CR25","doi-asserted-by":"publisher","first-page":"235","DOI":"10.1007\/s00381-017-3583-y","volume":"34","author":"HC Lee","year":"2018","unstructured":"Lee HC, Chong S, Lee JY et al (2018) Benign extracerebral fluid collection complicated by subdural hematoma and fluid collection: clinical characteristics and management. Childs Nerv Syst 34:235\u2013245","journal-title":"Childs Nerv Syst"},{"key":"6640_CR26","doi-asserted-by":"crossref","first-page":"245","DOI":"10.15274\/NRJ-2014-10020","volume":"27","author":"MA Marino","year":"2014","unstructured":"Marino MA, Morabito R, Vinci S et al (2014) Benign external hydrocephalus in infants. A single centre experience and literature review. Neuroradiol J 27:245\u2013250","journal-title":"Neuroradiol J"},{"key":"6640_CR27","doi-asserted-by":"crossref","first-page":"438","DOI":"10.3171\/2012.12.PEDS12289","volume":"11","author":"H McKeag","year":"2013","unstructured":"McKeag H, Christian CW, Rubin D et al (2013) Subdural hemorrhage in pediatric patients with enlargement of the subarachnoid spaces. J Neurosurg Pediatr 11:438\u2013444","journal-title":"J Neurosurg Pediatr"},{"key":"6640_CR28","first-page":"1725","volume":"27","author":"PD McNeely","year":"2006","unstructured":"McNeely PD, Atkinson JD, Saigal G et al (2006) Subdural hematomas in infants with benign enlargement of the subarachnoid spaces are not pathognomonic for child abuse. AJNR Am J Neuroradiol 27:1725\u20131728","journal-title":"AJNR Am J Neuroradiol"},{"key":"6640_CR29","doi-asserted-by":"publisher","first-page":"282","DOI":"10.1007\/BF00306274","volume":"9","author":"K Mori","year":"1993","unstructured":"Mori K, Sakamoto T, Nishimura K, Fujiwara K (1993) Subarachnoid fluid collection in infants complicated by subdural hematoma. Childs Nerv Syst 9:282\u2013284","journal-title":"Childs Nerv Syst"},{"key":"6640_CR30","doi-asserted-by":"crossref","unstructured":"Raissaki M, Adamsbaum C, Argyropoulou MI et al (2023) Benign enlargement of the subarachnoid spaces and subdural collections-when to evaluate for abuse. Pediatr Radiol 53:752\u2013767","DOI":"10.1007\/s00247-023-05611-y"},{"key":"6640_CR31","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1016\/S0887-8994(02)00500-3","volume":"28","author":"S Ravid","year":"2003","unstructured":"Ravid S, Maytal J (2003) External hydrocephalus: a probable cause for subdural hematoma in infancy. Pediatr Neurol 28:139\u2013141","journal-title":"Pediatr Neurol"},{"key":"6640_CR32","doi-asserted-by":"crossref","first-page":"16","DOI":"10.3171\/2015.12.PEDS15600","volume":"18","author":"J Tucker","year":"2016","unstructured":"Tucker J, Choudhary AK, Piatt J (2016) Macrocephaly in infancy: benign enlargement of the subarachnoid spaces and subdural collections. J Neurosurg Pediatr 18:16\u201320","journal-title":"J Neurosurg Pediatr"},{"key":"6640_CR33","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1159\/000322357","volume":"47","author":"AY Yew","year":"2011","unstructured":"Yew AY, Maher CO, Muraszko KM, Garton HJ (2011) Long-term health status in benign external hydrocephalus. Pediatr Neurosurg 47:1\u20136","journal-title":"Pediatr Neurosurg"},{"key":"6640_CR34","first-page":"855","volume":"14","author":"G Wilms","year":"1993","unstructured":"Wilms G, Vanderschueren G, Demaerel PH et al (1993) CT and MR in infants with pericerebral collections and macrocephaly: Benign enlargement of the subarachnoid spaces versus subdural collections. AJNR Am J Neuroradiol 14:855\u2013860","journal-title":"AJNR Am J Neuroradiol"},{"key":"6640_CR35","doi-asserted-by":"crossref","unstructured":"Choudhary AK, Servaes S, Slovis TL et al (2018) Consensus statement on abusive head trauma in infants and young children. Pediatr Radiol 48:1048\u20131065","DOI":"10.1007\/s00247-018-4149-1"},{"key":"6640_CR36","doi-asserted-by":"crossref","first-page":"188","DOI":"10.1159\/000055951","volume":"33","author":"NC Papasian","year":"2000","unstructured":"Papasian NC, Frim DM (2000) A theoretical model of benign external hydrocephalus that predicts a predisposition towards extra-axial hemorrhage after minor head trauma. Pediatr Neurosurg 33:188\u2013193","journal-title":"Pediatr Neurosurg"},{"key":"6640_CR37","doi-asserted-by":"publisher","first-page":"337","DOI":"10.1007\/s00414-008-0242-6","volume":"122","author":"JS Raul","year":"2008","unstructured":"Raul JS, Roth S, Ludes B, Willinger R (2008) Influence of the benign enlargement of the subarachnoid space on the bridging veins strain during a shaking event: A finite element study. Int J Legal Med 122:337\u2013340","journal-title":"Int J Legal Med"},{"key":"6640_CR38","doi-asserted-by":"crossref","unstructured":"Page MJ, McKenzie JE, Bossuyt PM et al (2021) The PRISMA 2020 statement: An updated guideline for reporting systematic reviews. PLoS Med 18:e1003583","DOI":"10.1371\/journal.pmed.1003583"},{"key":"6640_CR39","doi-asserted-by":"publisher","first-page":"210","DOI":"10.1186\/s13643-016-0384-4","volume":"5","author":"M Ouzzani","year":"2016","unstructured":"Ouzzani M, Hammady H, Fedorowicz Z, Elmagarmid A (2016) Rayyan\u2014a web and mobile app for systematic reviews. Syst Rev 5:210","journal-title":"Syst Rev"},{"key":"6640_CR40","doi-asserted-by":"crossref","unstructured":"Harris PA, Taylor R, Minor BL et al (2019) The REDCap consortium: Building an international community of software platform partners. J Biomed Inform 95:103208","DOI":"10.1016\/j.jbi.2019.103208"},{"key":"6640_CR41","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/j.jbi.2008.08.010","volume":"42","author":"PA Harris","year":"2009","unstructured":"Harris PA, Taylor R, Thielke R et al (2009) Research electronic data capture (REDCap)\u2014a metadata-driven methodology and workflow process for providing translational research informatics support. J Biomed Inform 42:377\u2013381","journal-title":"J Biomed Inform"},{"key":"6640_CR42","doi-asserted-by":"crossref","first-page":"443","DOI":"10.7863\/jum.2000.19.7.443","volume":"19","author":"DP Fessell","year":"2000","unstructured":"Fessell DP, Frankel DA, Wolfson WP (2000) Sonography of extraaxial fluid in neurologically normal infants with head circumference greater than or equal to the 95th percentile for age. J Ultrasound Med 19:443\u2013447","journal-title":"J Ultrasound Med"},{"key":"6640_CR43","doi-asserted-by":"crossref","unstructured":"Libicher M, Tr\u00f6ger J (1992) US measurement of the subarachnoid space in infants: normal values. Radiology 184:749\u2013751","DOI":"10.1148\/radiology.184.3.1509061"},{"key":"6640_CR44","doi-asserted-by":"publisher","first-page":"412","DOI":"10.1007\/BF00595899","volume":"148","author":"P Govaert","year":"1989","unstructured":"Govaert P, Pauwels W, Vanhaesebrouck P et al (1989) Ultrasound measurement of the subarachnoid space in infants. Eur J Pediatr 148:412\u2013413","journal-title":"Eur J Pediatr"},{"key":"6640_CR45","doi-asserted-by":"crossref","first-page":"410","DOI":"10.1177\/1971400917719298","volume":"30","author":"ZB Hussain","year":"2017","unstructured":"Hussain ZB, Hussain AB, Mitchell P (2017) Extra-axial cerebrospinal fluid spaces in children with benign external hydrocephalus: a case-control study. Neuroradiol J 30:410\u2013417","journal-title":"Neuroradiol J"},{"key":"6640_CR46","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1111\/j.1469-8749.1979.tb01645.x","volume":"21","author":"Y Fukuyama","year":"1979","unstructured":"Fukuyama Y, Miyao M, Ishizu T, Maruyama H (1979) Developmental changes in normal cranial measurements by computed tomography. Dev Med Child Neurol 21:425\u2013432","journal-title":"Dev Med Child Neurol"},{"key":"6640_CR47","doi-asserted-by":"publisher","first-page":"231","DOI":"10.1007\/BF00337531","volume":"17","author":"H Pedersen","year":"1979","unstructured":"Pedersen H, Gyldensted M, Gyldensted C (1979) Measurement of the normal ventricular system and supratentorial subarachnoid space in children with computed tomography. Neuroradiology 17:231\u2013237","journal-title":"Neuroradiology"},{"key":"6640_CR48","doi-asserted-by":"crossref","first-page":"428","DOI":"10.3171\/jns.1996.85.3.0428","volume":"85","author":"PD Sawin","year":"1996","unstructured":"Sawin PD, Muhonen MG, Menezes AH (1996) Quantitative analysis of cerebrospinal fluid spaces in children with occipital plagiocephaly. J Neurosurg 85:428\u2013434","journal-title":"J Neurosurg"},{"key":"6640_CR49","doi-asserted-by":"crossref","first-page":"254","DOI":"10.3171\/2016.8.PEDS16146","volume":"19","author":"AK Fingarson","year":"2017","unstructured":"Fingarson AK, Ryan ME, McLone SG et al (2017) Enlarged subarachnoid spaces and intracranial hemorrhage in children with accidental head trauma. J Neurosurg Pediatr 19:254\u2013258","journal-title":"J Neurosurg Pediatr"},{"key":"6640_CR50","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1159\/000095833","volume":"22","author":"E Danzer","year":"2007","unstructured":"Danzer E, Johnson MP, Bebbington M et al (2007) Fetal head biometry assessed by fetal magnetic resonance imaging following in utero myelomeningocele repair. Fetal Diagn Ther 22:1\u20136","journal-title":"Fetal Diagn Ther"},{"key":"6640_CR51","doi-asserted-by":"crossref","first-page":"418","DOI":"10.1177\/1971400916689803","volume":"30","author":"MT Whitehead","year":"2017","unstructured":"Whitehead MT, Lee B, McCarron A et al (2017) Reduced subarachnoid fluid diffusion in enlarged subarachnoid spaces of infancy. Neuroradiol J 30:418\u2013424","journal-title":"Neuroradiol J"},{"key":"6640_CR52","doi-asserted-by":"publisher","DOI":"10.1007\/s00247-023-05659-w","author":"CY Ho","year":"2023","unstructured":"Ho CY, Sankar M, Persohn S et al (2023) Quantitative assessment of cerebrospinal fluid flow and volume in enlargement of the subarachnoid spaces of infancy using MRI. Pediatr Radiol. https:\/\/doi.org\/10.1007\/s00247-023-05659-w","journal-title":"Pediatr Radiol"},{"key":"6640_CR53","doi-asserted-by":"crossref","first-page":"411","DOI":"10.7863\/jum.1998.17.7.411","volume":"17","author":"DA Frankel","year":"1998","unstructured":"Frankel DA, Fessell DP, Wolfson WP (1998) High resolution sonographic determination of the normal dimensions of the intracranial extraaxial compartment in the newborn infant. J Ultrasound Med 17:411\u2013415","journal-title":"J Ultrasound Med"},{"key":"6640_CR54","doi-asserted-by":"crossref","first-page":"F124","DOI":"10.1136\/fn.86.2.F124","volume":"86","author":"DL Armstrong","year":"2002","unstructured":"Armstrong DL, Bagnall C, Harding JE, Teele RL (2002) Measurement of the subarachnoid space by ultrasound in preterm infants. Arch Dis Child Fetal Neonatal Ed 86:F124-126","journal-title":"Arch Dis Child Fetal Neonatal Ed"},{"key":"6640_CR55","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.ultrasmedbio.2003.10.001","volume":"30","author":"NG Anderson","year":"2004","unstructured":"Anderson NG, Warfield SK, Wells S et al (2004) A limited range of measures of 2-D ultrasound correlate with 3-D MRI cerebral volumes in the premature infant at term. Ultrasound Med Biol 30:11\u201318","journal-title":"Ultrasound Med Biol"},{"key":"6640_CR56","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/j.ejrad.2005.11.007","volume":"58","author":"N Narli","year":"2006","unstructured":"Narli N, Soyupak S, Yildizda\u015f HY et al (2006) Ultrasonographic measurement of subarachnoid space in normal term newborns. Eur J Radiol 58:110\u2013112","journal-title":"Eur J Radiol"},{"key":"6640_CR57","doi-asserted-by":"crossref","first-page":"142","DOI":"10.5603\/FM.2013.0024","volume":"72","author":"A Okur","year":"2013","unstructured":"Okur A, Kucuk O, Karacavus S et al (2013) A novel index in healthy infants and children - subarachnoid space: ventricle ratio. Folia Morphol (Warsz) 72:142\u2013146","journal-title":"Folia Morphol (Warsz)"},{"key":"6640_CR58","doi-asserted-by":"crossref","unstructured":"Ng SM, Turner MA, Gamble C et al (2013) An explanatory randomised placebo controlled trial of levothyroxine supplementation for babies born <28 weeks\u2019 gestation: results of the TIPIT trial. Trials 14:211","DOI":"10.1186\/1745-6215-14-211"},{"key":"6640_CR59","doi-asserted-by":"crossref","unstructured":"Fandak J, Markart S, Willems EP et al (2024) Prospective measurement of the width of cerebrospinal fluid spaces by cranial ultrasound in neurologically healthy children aged 0-19 months. BMC Pediatr 24:315","DOI":"10.1186\/s12887-024-04797-w"},{"key":"6640_CR60","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1016\/j.pediatrneurol.2021.09.018","volume":"126","author":"J Andersson","year":"2022","unstructured":"Andersson J, Wikstr\u00f6m J, H\u00f6gberg U et al (2022) External hydrocephalus as a cause of infant subdural hematoma: epidemiological and radiological investigations of infants suspected of being abused. Pediatr Neurol 126:26\u201334","journal-title":"Pediatr Neurol"},{"key":"6640_CR61","doi-asserted-by":"crossref","first-page":"1223","DOI":"10.2214\/ajr.148.6.1223","volume":"148","author":"J Maytal","year":"1987","unstructured":"Maytal J, Alvarez LA, Elkin CM, Shinnar S (1987) External hydrocephalus: radiologic spectrum and differentiation from cerebral atrophy. AJR Am J Roentgenol 148:1223\u20131230","journal-title":"AJR Am J Roentgenol"},{"key":"6640_CR62","doi-asserted-by":"crossref","unstructured":"Cinalli G, di Martino G, Russo C et al (2021) Dural venous sinus anatomy in children with external hydrocephalus: analysis of a series of 97 patients. Childs Nerv Syst 37:3021\u20133032","DOI":"10.1007\/s00381-021-05322-5"},{"key":"6640_CR63","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1148\/radiology.141.1.7291548","volume":"141","author":"MT Modic","year":"1981","unstructured":"Modic MT, Kaufman B, Bonstelle CT et al (1981) Megalocephaly and hypodense extracerebral fluid collections. Radiology 141:93\u2013100","journal-title":"Radiology"},{"key":"6640_CR64","doi-asserted-by":"crossref","DOI":"10.1016\/j.jpeds.2025.114743","volume":"287","author":"S Karuparti","year":"2025","unstructured":"Karuparti S, Lizer A, Landwehr F et al (2025) Head growth in infants with benign enlargement of subarachnoid spaces versus macrocephaly. J Pediatr 287:114743","journal-title":"J Pediatr"},{"key":"6640_CR65","doi-asserted-by":"crossref","first-page":"e836","DOI":"10.1542\/peds.2010-0410","volume":"126","author":"C Daymont","year":"2010","unstructured":"Daymont C, Hwang WT, Feudtner C, Rubin D (2010) Head-circumference distribution in a large primary care network differs from CDC and WHO curves. Pediatrics 126:e836-842","journal-title":"Pediatrics"},{"key":"6640_CR66","doi-asserted-by":"crossref","unstructured":"Aoki N (1994) Extracerebral fluid collections in infancy: role of magnetic resonance imaging in differentiation between subdural effusion and subarachnoid space enlargement. J Neurosurg 81:20\u201323","DOI":"10.3171\/jns.1994.81.1.0020"},{"key":"6640_CR67","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1148\/radiology.201.2.8888229","volume":"201","author":"CY Chen","year":"1996","unstructured":"Chen CY, Chou TY, Zimmerman RA et al (1996) Pericerebral fluid collection: differentiation of enlarged subarachnoid spaces from subdural collections with color Doppler US. Radiology 201:389\u2013392","journal-title":"Radiology"},{"key":"6640_CR68","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1055\/s-2008-1071464","volume":"21","author":"LS De Vries","year":"1990","unstructured":"De Vries LS, Smet M, Ceulemans B et al (1990) The role of high resolution ultrasound and MRI in the investigation of infants with macrocephaly. Neuropediatrics 21:72\u201375","journal-title":"Neuropediatrics"},{"key":"6640_CR69","doi-asserted-by":"publisher","first-page":"251","DOI":"10.1007\/s00381-018-4007-3","volume":"35","author":"LV Sainz","year":"2019","unstructured":"Sainz LV, Zipfel J, Kerscher SR et al (2019) Cerebro-venous hypertension: a frequent cause of so-called \u201cexternal hydrocephalus\u201d in infants. Childs Nerv Syst 35:251\u2013256","journal-title":"Childs Nerv Syst"},{"key":"6640_CR70","doi-asserted-by":"crossref","unstructured":"Piatt JH Jr. (1999) A pitfall in the diagnosis of child abuse: external hydrocephalus, subdural hematoma, and retinal hemorrhages. Neurosurg Focus 7:e4","DOI":"10.3171\/foc.1999.7.4.6"},{"key":"6640_CR71","first-page":"398","volume":"11","author":"H Andersson","year":"1984","unstructured":"Andersson H, Elfverson J, Svendsen P (1984) External hydrocephalus in infants. Childs Brain 11:398\u2013402","journal-title":"Childs Brain"},{"key":"6640_CR72","doi-asserted-by":"publisher","first-page":"36","DOI":"10.1007\/BF00316560","volume":"8","author":"JC Odita","year":"1992","unstructured":"Odita JC (1992) The widened frontal subarachnoid space. Childs Nerv Syst 8:36\u201339","journal-title":"Childs Nerv Syst"},{"key":"6640_CR73","doi-asserted-by":"crossref","first-page":"541","DOI":"10.1001\/archneur.1978.00500320061014","volume":"35","author":"WC Robertson Jr.","year":"1978","unstructured":"Robertson WC Jr., Gomez MR (1978) External hydrocephalus. Early finding in congenital communicating hydrocephalus. Arch Neurol 35:541\u2013544","journal-title":"Arch Neurol"},{"key":"6640_CR74","doi-asserted-by":"crossref","unstructured":"Sahar A (1978) Pseudohydrocephalus-megalocephaly, increased intracranial pressure and widened subarachnoid space. Neuropadiatrie 9:131\u2013139","DOI":"10.1055\/s-0028-1085418"},{"key":"6640_CR75","doi-asserted-by":"publisher","first-page":"1113","DOI":"10.1007\/s00247-005-1503-x","volume":"35","author":"J Amodio","year":"2005","unstructured":"Amodio J, Spektor V, Pramanik B et al (2005) Spontaneous development of bilateral subdural hematomas in an infant with benign infantile hydrocephalus: Color Doppler assessment of vessels traversing extra-axial spaces. Pediatr Radiol 35:1113\u20131117","journal-title":"Pediatr Radiol"},{"key":"6640_CR76","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1148\/radiology.142.3.6977789","volume":"142","author":"A Kapila","year":"1982","unstructured":"Kapila A, Trice J, Spies WG et al (1982) Enlarged cerebrospinal fluid spaces in infants with subdural hematomas. Radiology 142:669\u2013672","journal-title":"Radiology"},{"key":"6640_CR77","doi-asserted-by":"crossref","first-page":"1217","DOI":"10.1002\/pd.1315","volume":"25","author":"Y Watanabe","year":"2005","unstructured":"Watanabe Y, Abe S, Takagi K et al (2005) Evolution of subarachnoid space in normal fetuses using magnetic resonance imaging. Prenat Diagn 25:1217\u20131222","journal-title":"Prenat Diagn"},{"key":"6640_CR78","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1016\/0887-8994(87)90021-X","volume":"3","author":"M Hamza","year":"1987","unstructured":"Hamza M, Bodensteiner JB, Noorani PA, Barnes PD (1987) Benign extracerebral fluid collections: A cause of macrocrania in infancy. Pediatr Neurol 3:218\u2013221","journal-title":"Pediatr Neurol"},{"key":"6640_CR79","doi-asserted-by":"publisher","first-page":"236","DOI":"10.1007\/BF02019655","volume":"20","author":"C Veyrac","year":"1990","unstructured":"Veyrac C, Couture A, Baud C (1990) Pericerebral fluid collections and ultrasound. Pediatr Radiol 20:236\u2013240","journal-title":"Pediatr Radiol"},{"key":"6640_CR80","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-019-55604-x","volume":"9","author":"SK Yum","year":"2019","unstructured":"Yum SK, Im SA, Seo YM, Sung IK (2019) Enlarged subarachnoid space on cranial ultrasound in preterm infants: Neurodevelopmental implication. Sci Rep 9:19072","journal-title":"Sci Rep"},{"key":"6640_CR81","doi-asserted-by":"publisher","first-page":"1195","DOI":"10.1007\/s00381-010-1105-2","volume":"26","author":"M Vinchon","year":"2010","unstructured":"Vinchon M, Delestret I, DeFoort-Dhellemmes S et al (2010) Subdural hematoma in infants: can it occur spontaneously? Data from a prospective series and critical review of the literature. Childs Nerv Syst 26:1195\u20131205","journal-title":"Childs Nerv Syst"},{"key":"6640_CR82","doi-asserted-by":"crossref","unstructured":"Bethlehem RAI, Seidlitz J, White SR et al (2022) Brain charts for the human lifespan. Nature 604:525\u2013533","DOI":"10.1038\/s41586-022-04554-y"}],"container-title":["Pediatric Radiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00247-026-06640-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00247-026-06640-z","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00247-026-06640-z.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T00:10:19Z","timestamp":1792023019000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00247-026-06640-z"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,6]]},"references-count":82,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2026,10]]}},"alternative-id":["6640"],"URL":"https:\/\/doi.org\/10.1007\/s00247-026-06640-z","relation":{},"ISSN":["1432-1998"],"issn-type":[{"value":"1432-1998","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,6]]},"assertion":[{"value":"23 February 2026","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"30 April 2026","order":2,"name":"revised","label":"Revised","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"1 May 2026","order":3,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"6 June 2026","order":4,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"AAB holds equity in Centile Bioscience. JS is a director of and holds equity in Centile Bioscience. All other authors declare that they have no competing interests to declare that are relevant to the content of this article. MKH and BHC have provided testimony in cases with concern for child maltreatment for which their institution received payment.\u00a0The content, findings, and conclusions are solely the responsibility of the authors and does not necessarily represent the views of the National Institutes of Health, AHRQ, or HHS. Readers should not interpret any statement in this report as an official position of AHRQ or of HHS. None of the authors has any affiliation or financial involvement that conflicts with the material presented in this report unless otherwise reported.","order":1,"name":"Ethics","label":"Conflicts of interest","group":{"name":"EthicsHeading","label":"Declarations"}}]}}