Elke De Witte1, Wim Van Hecke2, Guido Dua3, Didier De Surgeloose4, Maarten Moens5, Peter Mariën6. 1. Department of Clinical and Experimental Neurolinguistics, CLIN, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium. 2. Department of Radiology, Antwerp University Hospital, Wilrijkstraat 10, B-2650 Antwerp, Belgium; icoMetrix, Tervuursesteenweg 244, B-3001 Leuven, Belgium. 3. Department of Neurosurgery, ZNA Middelheim General Hospital, Lindendreef 1, B-2020 Antwerp, Belgium. 4. Department of Radiology, ZNA Middelheim General Hospital, Lindendreef 1, B-2020 Antwerp, Belgium. 5. Department of Neurosurgery and Center for Neuroscience, Universitair Ziekenhuis Brussel, Laarbeeklaan 101, B-1090 Brussels, Belgium. 6. Department of Clinical and Experimental Neurolinguistics, CLIN, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium; VLAC (Vlaams Academisch Centrum), Advanced Studies Institute of the Royal Flemish Academy of Belgium for Sciences and the Arts, Brussels, Belgium; Department of Neurology & Memory Clinic, ZNA Middelheim General Hospital, Lindendreef 1, B-2020 Antwerp, Belgium. Electronic address: peter.marien5@telenet.be.
Abstract
OBJECTIVE: Approximately 97% of the right-handers has left hemisphere language dominance. Within the language dominant hemisphere Broca's area is of crucial importance for a variety of linguistic functions. As a result, tumour resection in and around Broca's area is controversial. However, studies showed that by means of Direct Electrical Stimulation (DES) tumour resection in this region can be safely performed. We report unexpected anatomoclinical findings in a right-handed patient who underwent tumour resection in the left prefrontal lobe. METHODS: Language functions in this right-handed patient were extensively examined in the pre-, intra-, and postoperative phase by means of a standardised battery of neurolinguistic and neurocognitive tests. Results obtained in the pre- and postoperative phase are compared. In addition, intraoperative DES findings and postoperative functional Magnetic Resonance Imaging (fMRI) and Diffusion Tensor Imaging (DTI) results are reported. RESULTS: Tumour resection near Broca's area was safely performed since no positive language sites were found during intraoperative DES. Since no linguistic deficits occurred in the pre-, intra-, or postoperative phase, atypical language dominance was suspected. Neuropsychological investigations, however, disclosed permanent executive dysfunction. Postoperative fMRI and DTI confirmed right cerebral language dominance as well as a crossed cerebro-cerebellar functional link with the left cerebellar hemisphere. DISCUSSION: Atypical right hemisphere language dominance in this right-handed patient is reflected by: (1) the total absence of language problems in the pre-, intra- and postoperative phase, (2) absence of positive stimulation sites during DES, (3) a clearly more pronounced arcuate fasciculus in the right cerebral hemisphere (DTI), (4) a crossed functional connection between the right cerebrum and the left cerebellum (fMRI). Two hypothetical explanations for the pattern of crossed cerebral language dominance are put forward: (1) preoperative brain plasticity mechanisms inducing a shift of language functions to the right hemisphere or (2) right hemisphere language dominance as a maturational variant. This case with atypical cerebral language dominance shows that although DES is the 'gold standard' to identify eloquent language regions and their pathways, fMRI and DTI are important adjuncts to guide surgery, to identify language lateralisation and to study anatomoclinical correlations.
OBJECTIVE: Approximately 97% of the right-handers has left hemisphere language dominance. Within the language dominant hemisphere Broca's area is of crucial importance for a variety of linguistic functions. As a result, tumour resection in and around Broca's area is controversial. However, studies showed that by means of Direct Electrical Stimulation (DES) tumour resection in this region can be safely performed. We report unexpected anatomoclinical findings in a right-handed patient who underwent tumour resection in the left prefrontal lobe. METHODS: Language functions in this right-handed patient were extensively examined in the pre-, intra-, and postoperative phase by means of a standardised battery of neurolinguistic and neurocognitive tests. Results obtained in the pre- and postoperative phase are compared. In addition, intraoperative DES findings and postoperative functional Magnetic Resonance Imaging (fMRI) and Diffusion Tensor Imaging (DTI) results are reported. RESULTS:Tumour resection near Broca's area was safely performed since no positive language sites were found during intraoperative DES. Since no linguistic deficits occurred in the pre-, intra-, or postoperative phase, atypical language dominance was suspected. Neuropsychological investigations, however, disclosed permanent executive dysfunction. Postoperative fMRI and DTI confirmed right cerebral language dominance as well as a crossed cerebro-cerebellar functional link with the left cerebellar hemisphere. DISCUSSION: Atypical right hemisphere language dominance in this right-handed patient is reflected by: (1) the total absence of language problems in the pre-, intra- and postoperative phase, (2) absence of positive stimulation sites during DES, (3) a clearly more pronounced arcuate fasciculus in the right cerebral hemisphere (DTI), (4) a crossed functional connection between the right cerebrum and the left cerebellum (fMRI). Two hypothetical explanations for the pattern of crossed cerebral language dominance are put forward: (1) preoperative brain plasticity mechanisms inducing a shift of language functions to the right hemisphere or (2) right hemisphere language dominance as a maturational variant. This case with atypical cerebral language dominance shows that although DES is the 'gold standard' to identify eloquent language regions and their pathways, fMRI and DTI are important adjuncts to guide surgery, to identify language lateralisation and to study anatomoclinical correlations.
Authors: Vitória Piai; Elke De Witte; Joanna Sierpowska; Xiaochen Zheng; Leighton B Hinkley; Danielle Mizuiri; Robert T Knight; Mitchel S Berger; Srikantan S Nagarajan Journal: J Cogn Neurosci Date: 2020-04-14 Impact factor: 3.225
Authors: Wenwen Gao; Xiaowei Han; Haimei Li; Yijiang Zhu; Lei Du; Yuli Wang; Sumin Shi; Jing Liu; Chao Fu; Lu Zhang; Guolin Ma Journal: Ann Transl Med Date: 2020-06
Authors: Luca Pasquini; Alberto Di Napoli; Maria Camilla Rossi-Espagnet; Emiliano Visconti; Antonio Napolitano; Andrea Romano; Alessandro Bozzao; Kyung K Peck; Andrei I Holodny Journal: Front Hum Neurosci Date: 2022-02-18 Impact factor: 3.169