title: DTI fiber tractography of cerebro-cerebellar pathways and clinical evaluation of ataxia in childhood posterior fossa tumor survivors.
abstract: Pediatric posterior fossa (PF) tumor survivors experience long-term motor deficits. Specific cerebrocerebellar connections may be involved in incidence and severity of motor dysfunction. We examined the relationship between long-term ataxia as well as fine motor function and alteration of differential cerebellar efferent and afferent pathways using diffusion tensor imaging (DTI) and tractography. DTI-based tractography was performed in 19 patients (10 pilocytic astrocytoma (PA) and 9 medulloblastoma patients (MB)) and 20 healthy peers. Efferent Cerebello-Thalamo-Cerebral (CTC) and afferent Cerebro-Ponto-Cerebellar (CPC) tracts were reconstructed and analyzed concerning fractional anisotropy (FA) and volumetric measurements. Clinical outcome was assessed with the International Cooperative Ataxia Rating Scale (ICARS). Kinematic parameters of fine motor function (speed, automation, variability, and pressure) were obtained by employing a digitizing graphic tablet. ICARS scores were significantly higher in MB patients than in PA patients. Poorer ICARS scores and impaired fine motor function correlated significantly with volume loss of CTC pathway in MB patients, but not in PA patients. Patients with pediatric post-operative cerebellar mutism syndrome showed higher loss of CTC pathway volume and were more atactic. CPC pathway volume was significantly reduced in PA patients, but not in MB patients. Neither relationship was observed between the CPC pathway and ICARS or fine motor function. There was no group difference of FA values between the patients and healthy peers. Reduced CTC pathway volumes in our cohorts were associated with severity of long-term ataxia and impaired fine motor function in survivors of MBs. We suggest that the CTC pathway seems to play a role in extent of ataxia and fine motor dysfunction after childhood cerebellar tumor treatment. DTI may be a useful tool to identify relevant structures of the CTC pathway and possibly avoid surgically induced long-term neurological sequelae.
authors: Pediatric Neurosurgery, Charité-Universitätsmedizin Berlin, Campus Virchow Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.
authors: Myung Eun
authors: ME
authors: Oh
authors: Pediatric Neurooncology Program, Department of Pediatric Oncology and Hematology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors: Pablo Hernáiz
authors: PH
authors: Driever
authors: Pediatric Neurooncology Program, Department of Pediatric Oncology and Hematology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors: Rajiv K
authors: RK
authors: Khajuria
authors: Pediatric Neurooncology Program, Department of Pediatric Oncology and Hematology, Charité-Universitätsmedizin Berlin, Berlin, Germany.|Department of Neurosurgery, University Hospital Würzburg, Würzburg, Germany.
authors: Stefan Mark
authors: SM
authors: Rueckriegel
authors: Pediatric Neurooncology Program, Department of Pediatric Oncology and Hematology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors: Elisabeth
authors: E
authors: Koustenis
authors: Institute of Diagnostic and Interventional Radiology, Friedrich Schiller University Jena, Jena, Germany.
authors: Harald
authors: H
authors: Bruhn
authors: Pediatric Neurosurgery, Charité-Universitätsmedizin Berlin, Campus Virchow Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany. uthomale@charite.de.
authors: Ulrich-Wilhelm
authors: UW
authors: Thomale
mesh_terms: D000293:Adolescent; D001254:Astrocytoma / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*; D001259:Ataxia / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology*; D000073116:Cancer Survivors; D002528:Cerebellar Neoplasms / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*; D002531:Cerebellum / Q000000981:diagnostic imaging / Q000473:pathology*; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D015192:Infratentorial Neoplasms / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008527:Medulloblastoma / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000473:pathology
keywords: Ataxia; Cerebro-cerebellar pathways; Childhood posterior fossa tumor; Diffusion tensor imaging (DTI); Fine motor function