Objectives: Chiari II malformation is a congenital abnormality characterized by a small posterior fossa with downward displacement of the hindbrain into the foramen magnum. Diffusion-weighted imaging (DWI) can be used to quantitatively characterize brain injury and physiological maturation. We aim to evaluate DWI parameters of the infra- and supratentorial brain in fetuses with Chiari II malformation. Methods:MRI and US studies of 26 fetuses with Chiari II malformation and 15 controls were evaluated for the presence/severity of hydrocephalus, myelomeningocele level, and brain apparent diffusion coefficient (ADC) values. Cerebral flow impedance parameters (resistance and pulsatile indexes, resistance index [RI], and pulsatility index [PI] respectively) from concurrently preformed fetal US were also evaluated. Results: Of the Chiari II group, 16 fetuses had hydrocephalus. There was increasing severity of lateral ventriculomegaly in the high compared to low spinal dysraphism subgroups. There were significant lower ADC values in the frontal (p = 0.01) and temporal lobes (p = 0.05) in Chiari II group compared with normal, regardless of the presence or severity of hydrocephalus. Fetuses with Chiari II showed significantly lower RI and PI values. Conclusions: Abnormal ADC values indicate supratentorial microstructural changes in fetuses with Chiari II malformation. Further investigation of the role of diffusion imaging metrics in evaluating abnormal brain development, parenchymal damage and efficacy of fetal surgery is needed.

1.
McLone DG, Knepper PA: The cause of Chiari II malformation: a unified theory. Pediatr Neurosci 1989; 15: 1–12.
2.
Nagaraj UD, Bierbrauer KS, Zhang B, Peiro JL, Kline-Fath BM: Hindbrain Herniation in Chiari II Malformation on Fetal and Postnatal MRI. AJNR Am J Neuroradiol 2017; 38: 1031–1036.
3.
Rethmann C, Scheer I, Meuli M, Mazzone L, Moehrlen U, Kellenberger CJ: Evolution of posterior fossa and brain morphology after in utero repair of open neural tube defects assessed by MRI. Eur Radiol 2017; 27: 4571–4580.
4.
Paolo Tortori-Donati, Andrea Rossi, Roberta Biancheri: Brain Malformations; in Paolo Tortori-Donati, Andrea Rossi (eds): Pediatric Neuroradiology. Springer-Verlag Berlin Heidelberg, 2005, pp 71–198.
5.
Poretti A, Boltshauser E, Huisman TA: Chiari Malformations and Syringohydromyelia in Children. Semin Ultrasound CT MR 2016; 37: 129–142.
6.
Schneider JF, Confort-Gouny S, Le Fur Y, Viout P, Bennathan M, Chapon F, Fogliarini C, Cozzone P, Girard N: Diffusion-weighted imaging in normal fetal brain maturation. Eur Radiol 2007; 17: 2422–2429.
7.
Kasprian G, Del RM, Prayer D: Fetal diffusion imaging: pearls and solutions. Top Magn Reson Imaging 2010; 21: 387–394.
8.
Pople IK, Quinn MW, Bayston R, Hayward RD: The Doppler pulsatility index as a screening test for blocked ventriculo-peritoneal shunts. Eur J Pediatr Surg 1991; 1(suppl 1): 27–29.
9.
Kirkinen P, Muller R, Baumann H, Briner J, Lang W, Huch R, Huch A: Cerebral blood flow velocity waveforms in hydrocephalic fetuses. J Clin Ultrasound 1988; 16: 493–498.
10.
Barkovich AJ, Raybaud C: Congential Malformation of the Brain and Skull; in Barkovich AJ, Raybaud C (eds): Pediatric Neuroimaging. Philadelphia, Lippincott Williams & Wilkins, 2012, pp 367–568.
11.
Dias MS, McLone DG: Hydrocephalus in the child with dysraphism. Neurosurg Clin N Am 1993; 4: 715–726.
12.
Tamburrini G, Frassanito P, Iakovaki K, Pignotti F, Rendeli C, Murolo D, Di Rocco C: Myelomeningocele: the management of the associated hydrocephalus. Childs Nerv Syst 2013; 29: 1569–1579.
13.
Boyer AC, Goncalves LF, Lee W, Shetty A, Holman A, Yeo L, Romero R: Magnetic resonance diffusion-weighted imaging: reproducibility of regional apparent diffusion coefficients for the normal fetal brain. Ultrasound Obstet Gynecol 2013; 41: 190–197.
14.
Schneider MM, Berman JI, Baumer FM, Glass HC, Jeng S, Jeremy RJ, Esch M, Biran V, Barkovich AJ, Studholme C, Xu D, Glenn OA: Normative apparent diffusion coefficient values in the developing fetal brain. AJNR Am J Neuroradiol 2009; 30: 1799–1803.
15.
Yaniv G, Katorza E, Bercovitz R, Bergman D, Greenberg G, Biegon A, Hoffmann C: Region-specific changes in brain diffusivity in fetal isolated mild ventriculomegaly. Eur Radiol 2016; 26: 840–848.
16.
Erdem G, Celik O, Hascalik S, Karakas HM, Alkan A, Firat AK: Diffusion-weighted imaging evaluation of subtle cerebral microstructural changes in intrauterine fetal hydrocephalus. Magn Reson Imaging 2007; 25: 1417–1422.
17.
Baldoli C, Righini A, Parazzini C, Scotti G, Triulzi F: Demonstration of acute ischemic lesions in the fetal brain by diffusion magnetic resonance imaging. Ann Neurol 2002; 52: 243–246.
18.
Guimiot F, Garel C, Fallet-Bianco C, Menez F, Khung-Savatovsky S, Oury JF, Sebag G, Delezoide AL: Contribution of diffusion-weighted imaging in the evaluation of diffuse white matter ischemic lesions in fetuses: correlations with fetopathologic findings. AJNR Am J Neuroradiol 2008; 29: 110–115.
19.
Mignone PC, Shannon P, Chitayat D, Ryan G, Raybaud CA, Blaser SI: Diffusion-weighted imaging of the cerebellum in the fetus with Chiari II malformation. AJNR Am J Neuroradiol 2013; 34: 1656–1660.
20.
Woitek R, Prayer D, Weber M, Amann G, Seidl R, Bettelheim D, Schopf V, Brugger PC, Furtner J, Asenbaum U, Kasprian G: Fetal diffusion tensor quantification of brainstem pathology in Chiari II malformation. Eur Radiol 2016; 26: 1274–1283.
21.
Boltshauser E, Schneider J, Kollias S, Waibel P, Weissert M: Vanishing cerebellum in myelomeningocoele. Eur J Paediatr Neurol 2002; 6: 109–113.
22.
Vyas S, Nicolaides KH, Bower S, Campbell S: Middle cerebral artery flow velocity waveforms in fetal hypoxaemia. Br J Obstet Gynaecol 1990; 97: 797–803.
23.
Tarzamni MK, Nezami N, Sobhani N, Eshraghi N, Tarzamni M, Talebi Y: Nomograms of Iranian fetal middle cerebral artery Doppler waveforms and uniformity of their pattern with other populations’ nomograms. BMC Pregnancy Childbirth 2008; 8: 50.
24.
Righini A, Bianchini E, Parazzini C, Gementi P, Ramenghi L, Baldoli C, Nicolini U, Mosca F, Triulzi F: Apparent diffusion coefficient determination in normal fetal brain: a prenatal MR imaging study. AJNR Am J Neuroradiol 2003; 24: 799–804.
25.
Manganaro L, Perrone A, Savelli S, Di MM, Maggi C, Ballesio L, Porfiri LM, De FC, Marinoni E, Marini M: Evaluation of normal brain development by prenatal MR imaging. Radiol Med 2007; 112: 444–455.
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