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Johann Peltier, Patrick Toussaint, Christine Desenclos, Daniel Le Gars and Herve Deramond

✓ The authors emphasize an unusual complication of venous angiomas in the brain: venous infarction. The patient in this case is a 32-year-old man who presented with a clinical history of headache followed by a worsening of his neurological status. Neuroimaging studies demonstrated a brain infarct in the posterior fossa, which was related to thrombosis of the draining vein of a cerebral venous angioma. A conservative treatment approach without anticoagulation therapy was followed and the patient completely recovered. Nonhemorragic venous infarction caused by thrombosis of a venous angioma is exceptional and only nine previous cases have been reported in the literature.

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Michel Lefranc, Cyrille Capel, Anne-Sophie Pruvot-Occean, Anthony Fichten, Christine Desenclos, Patrick Toussaint, Daniel Le Gars and Johann Peltier


Stereotactic biopsy procedures are an everyday part of neurosurgery. The procedure provides an accurate histological diagnosis with the least possible morbidity. Robotic stereotactic biopsy needs to be an accurate, safe, frameless, and rapid technique. This article reports the clinical results of a series of 100 frameless robotic biopsies using a Medtech ROSA device.


The authors retrospectively analyzed their first 100 frameless stereotactic biopsies performed with the robotic ROSA device: 84 biopsies were performed by frameless robotic surface registration, 7 were performed by robotic bone fiducial marker registration, and 9 were performed by scalp fiducial marker registration. Intraoperative flat-panel CT scanning was performed concomitantly in 25 cases. The operative details of the robotic biopsies, the diagnostic yield, and mortality and morbidity data observed in this series are reported.


A histological diagnosis was established in 97 patients. No deaths or permanent morbidity related to surgery were observed. Six patients experienced transient neurological worsening. Six cases of bleeding within the lesion or along the biopsy trajectory were observed on postoperative CT scans but were associated with transient clinical symptoms in only 2 cases. Stereotactic surgery was performed with patients in the supine position in 93 cases and in the prone position in 7 cases. The use of fiducial markers was reserved for posterior fossa biopsy via a transcerebellar approach, via an occipital approach, or for pediatric biopsy.


ROSA frameless stereotactic biopsies appear to be accurate and safe robotized frameless procedures.

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Johann Peltier, Michel Lefranc, Anthony Fichten, Carole Cordonnier, Patrick Toussaint, Christine Desenclos and Daniel Le Gars

✓The authors report the case of a 31-year-old man with polyostotic fibrous dysplasia who suffered a traumatic odontoid fracture in an area of a preexisting bone lesion. Conservative treatment was successfully performed. Jaffe–Lichtenstein disease is discussed along with differential diagnoses and alternative methods of treatment.

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Johann Peltier, Sébastien Verclytte, Christine Delmaire, Jean-Pierre Pruvo, Olivier Godefroy and Daniel Le Gars


The authors used a fiber dissection technique to describe the temporal stem and explain the tendency of malignant tumors to spread within both the frontal and temporal lobes. The authors focused on the morphological characteristics and course of various fasciculi of the temporal stem, including the uncinate fascicle, occipitofrontal fascicle, anterior commissure, loop of the optic radiations (Meyer loop), and the ansa peduncularis.


Eight previously frozen, formalin-fixed human brains were dissected under an operating microscope using the fiber dissection technique described by Klingler. Lateral, inferior, and medial approaches were made. Cross-sectional 3D MR images obtained in 10 patients without brain lesions demonstrated that fibers of the temporal stem, which were intermingled together in various ways, curved laterally within the basal forebrain. Various pathological entities affecting the temporal stem are described and discussed.


The uncinate fascicle has 3 portions: a ventral extension, an intermediary segment called the isthmus, and a dorsal segment. The inferior occipitofrontal fasciculus is a layer of more superficial white matter that appeared to be superior to the uncinate fasciculus. A short ventral portion of the radiations of the corpus callosum was sometimes noted to run ventrally to enter the temporal stem and to reach both temporal lobes.


To the authors' knowledge, a detailed anatomy of the temporal stem has not been previously described in the literature. The unique anatomy of the temporal stem provides a route for tumor spread between the frontal and temporal lobes.

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Johann Peltier, Sébastien Verclytte, Christine Delmaire, Hervé Deramond, Jean-Pierre Pruvo, Daniel Le Gars and Olivier Godefroy


In the current literature, there is a lack of a detailed map of the origin, course, and connections of the ventral callosal radiations of the human brain.


The authors used an older dissection technique based on a freezing process as well as diffusion tensor imaging to investigate this area of the human brain.


The authors demonstrated interconnections between areas 11, 12, and 25 for the callosal radiations of the trunk and rostrum of the corpus callosum; between areas 9, 10, and 32 for the genu; and between areas 6, 8, and 9 for the ventral third of the body. The authors identified new ventral callosal connections crossing the rostrum between both temporal poles and coursing within the temporal stem, and they named these connections the “callosal radiations of Peltier.” They found that the breadth of the callosal radiations slightly increases along their course from the rostrum to the first third of the body of the corpus callosum.


The fiber dissection and diffusion tensor imaging techniques are complementary not only in their application to the study of the commissural system in the human brain, but also in their practical use for diagnosis and surgical planning. Further investigations, neurocognitive tests, and other contributions will permit elucidation of the functional relevance of the newly identified callosal radiations in patients with disease involving the ventral corpus callosum.