title: A rare case of cerebellar agenesis: a probabilistic Constrained Spherical Deconvolution tractographic study.
abstract: Aim of this study is to show the potential of probabilistic tractographic techniques, based on the Constrained Spherical Deconvolution (CSD) algorithms, in recognizing white matter fiber bundle anomalies in patients with complex cerebral malformations, such as cerebellar agenesis. The morphological and tractographic study of a 17-year-old male patient affected by cerebellar agenesis was performed by using a 3Tesla MRI scanner. Genetic and neuropsychological tests were carried out. An MRI morphological study showed the absence of both cerebellar hemispheres and the flattening of the anterior side of the pons. Moreover, it showed a severe vermian hypoplasia with a minimal vermian residual. The study recognized two thin cerebellar remnants, medially in contact with the small vermian residual, at the pontine level. The third ventricle, morphologically normal, communicated with a permagna cerebello-medullary cistern. Probabilistic CSD tractography identified some abnormal and aberrant infratentorial tracts, symmetrical on both sides. In particular, the transverse pontine fibers were absent and the following tracts with aberrant trajectories have been identified: "cerebello-thalamic" tracts; "fronto-cerebellar" tracts; and ipsilateral and contralateral "spino-cerebellar" tracts. Abnormal tracts connecting the two thin cerebellar remnants have also been detected. There were no visible alterations in the main supratentorial tracts in either side. Neuropsychiatric evaluation showed moderate cognitive-motor impairment with discrete adaptive compensation. Probabilistic CSD tractography is a promising technique that overcome reconstruction biases of other diffusion tensor-based approaches and allowed us to recognize, in a patient with cerebellar agenesis, abnormal tracts and aberrant trajectories of normally existing tracts.
authors.affiliation: Neuroradiology Unit - Department of Biomedical Sciences and Morpho-Functional Imaging, University of Messina, via Consolare Valeria, 1 A.O.U. Policlinico "G. Martino", 98125, Messina, Italy.
authors.forename: Enricomaria
authors.initials: E
authors.lastname: Mormina
authors.affiliation: Department of Pediatric, Gynecological, Microbiological and Biomedical Sciences, University of Messina, Messina, Italy.
authors.forename: Marilena
authors.initials: M
authors.lastname: Briguglio
authors.affiliation: Neuroradiology Unit - Department of Biomedical Sciences and Morpho-Functional Imaging, University of Messina, via Consolare Valeria, 1 A.O.U. Policlinico "G. Martino", 98125, Messina, Italy.
authors.forename: Rosa
authors.initials: R
authors.lastname: Morabito
authors.affiliation: Neuroradiology Unit - Department of Biomedical Sciences and Morpho-Functional Imaging, University of Messina, via Consolare Valeria, 1 A.O.U. Policlinico "G. Martino", 98125, Messina, Italy. alessandro.arrigo@hotmail.com.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Arrigo
authors.affiliation: IRCCS Centro Neurolesi Bonino-Pulejo, Messina, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Marino
authors.affiliation: Department of Pediatric, Gynecological, Microbiological and Biomedical Sciences, University of Messina, Messina, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Di Rosa
authors.affiliation: IRCCS Casa Sollievo della Sofferenza, CSS-Mendel Laboratory, San Giovanni Rotondo, Italy.|Department of Biological and Environmental Science, University of Messina, Messina, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Micalizzi
authors.affiliation: IRCCS Casa Sollievo della Sofferenza, CSS-Mendel Laboratory, San Giovanni Rotondo, Italy.|Section of Neurosciences, Department of Medicine and Surgery, University of Salerno, Salerno, Italy.
authors.forename: Enza Maria
authors.initials: EM
authors.lastname: Valente
authors.affiliation: Department of Pediatric, Gynecological, Microbiological and Biomedical Sciences, University of Messina, Messina, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Salpietro
authors.affiliation: Neuroradiology Unit - Department of Biomedical Sciences and Morpho-Functional Imaging, University of Messina, via Consolare Valeria, 1 A.O.U. Policlinico "G. Martino", 98125, Messina, Italy.
authors.forename: Sergio Lucio
authors.initials: SL
authors.lastname: Vinci
authors.affiliation: Neuroradiology Unit - Department of Biomedical Sciences and Morpho-Functional Imaging, University of Messina, via Consolare Valeria, 1 A.O.U. Policlinico "G. Martino", 98125, Messina, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Longo
authors.affiliation: Neuroradiology Unit - Department of Biomedical Sciences and Morpho-Functional Imaging, University of Messina, via Consolare Valeria, 1 A.O.U. Policlinico "G. Martino", 98125, Messina, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Granata
mesh_terms: D000293:Adolescent; D000465:Algorithms; D002531:Cerebellum / Q000002:abnormalities* / Q000000981:diagnostic imaging*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D009434:Neural Pathways / Q000002:abnormalities / Q000000981:diagnostic imaging; D011149:Pons / Q000002:abnormalities / Q000000981:diagnostic imaging; D066127:White Matter / Q000002:abnormalities / Q000000981:diagnostic imaging
keywords: Cerebellar agenesis; Cerebellar hypoplasia; Hindbrain malformation; Pons malformation; Probabilistic; Tractography