Biomedical subjects

H Duffau

Publications and source records attributed to H Duffau.

48 records · Page 3Linked to original sources

PubMed2000

Intraoperative unmasking of brain redundant motor sites during resection of a precentral angioma: evidence using direct cortical stimulation.

We report the first observation of real-time intraoperative evidence of a retrocentral redistribution of motor areas with an unmasking of precentral redundant motor sites, before and after, respectively, surgical removal of a precentral arteriovenous malformation using direct electrical stimulation. This study shows large-scale plasticity of the motor function behind the central sulcus as the result of an arteriovenous malformation, the brain's ability to effect short-term unmasking of precentral motor sites after arteriovenous malformation resection, and the existence of redundant precentral and postcentral motor areas for the same movement, suggesting that the central sulcus does not simply divide motor and sensory functions.

Adult↗

PubMed1999

Intra-operative direct electrical stimulations of the central nervous system: the Salpêtrière experience with 60 patients.

Indications of surgical treatment for lesions in the central nervous system depend on the risk of a definitive neurological deficit, related to the benefit of resection. Detection of eloquent areas is then necessary because of major individual variability. Neuro-imaging functional techniques are in development and are beginning to be efficient for cortical sensorymotor mapping, but still lack sensitivity and specificity for language mapping, and remain unable to give real-time data during surgery and to perform sub-cortical mapping. The more precise and reliable method of functional mapping is represented by the intra-operative direct electrical stimulations (DES), which allow identification and preservation of essential pathways for motricity, sensibility and language, at each level of the central nervous system (cortico-subcortical). We report our experience of DES in the surgery of tumours and vascular malformations located in supra-tentorial brain eloquent areas, with a consecutive series of 60 patients operated on under general or local anaesthesia, from November 1996 until May 1999 in our department at La Salpêtrière Hospital. Presenting symptoms in the 60 subjects (39 males, 21 females, mean age: 45 years) were seizures in 37 cases with normal clinical examination, and mild neurological deficit in 29 cases. MRI showed 60 supra-tentorial brain lesions: 30 precentral, 12 postcentral, 14 perisylvian in the dominant hemisphere, 4 deep-seated. All subjects underwent surgical resection using DES, with supratentorial cortico-subcortical mapping under general anaesthesia for motor areas detection in 43 cases and under local anaesthesia for sensori-motor and/or language tasks in 17 cases. The final histological diagnosis was 44 gliomas (31 low-grade and 13 high-grade), 9 metastasis, 3 cavernomas, 4 arteriovenous malformations (AVM). Resection was total or subtotal in 52 cases (87%) and partial in 8 cases (13%). 29 patients had no post-operative deficit, while the other 31 patients were impaired post-operatively, with in all cases, except 3, a complete recovery delayed for 15 days to 3 months (overall morbidity: 5%). The median follow up was 14 months. Intra-operative direct electrical stimulations of the central nervous system constitute a reliable, precise and safe method, allowing the realization of a functional mapping useful for all operations of lesions located in eloquent areas. This technique allows a minimization of definitive post-operative neurological deficit, and concurrently an improvement in the quality of resection.

Adult↗

PubMed1999

Primary spheno-orbital angiosarcoma: case report and review of the literature.

OBJECTIVE: Angiosarcoma is a rare neoplasm that uncommonly involves the cranium. We report the second case in the literature of a primary right spheno-orbital malignant angiosarcoma. CLINICAL PRESENTATION: This 43-year-old man experienced a 3-month history of rapid growing temporal mass. The results of his neurological examination were normal. Neuroimaging revealed an intensively enhanced right spheno-orbital lesion, with destruction of the greater wing of the sphenoid bone and extension into the orbit, the infratemporal fossa, and the temporal fossa with infiltration of the dura mater but without parenchymal abnormality. INTERVENTION: The tumor was first biopsied and then totally removed, with exenteration of the right eye. The histological features were typical of angiosarcoma with immunohistochemical evidence of Factor VIII-related antigen produced by tumor cells. Neither radiotherapy nor chemotherapy was performed. The patient remained well during 16 months of follow-up, without evidence of recurrence on magnetic resonance images. CONCLUSION: We emphasize the benefit of wide surgical resection without systematic complementary treatment (radiotherapy and/or chemotherapy) in a case of primary angiosarcoma of the cranium. The literature is reviewed.

Adult↗

PubMed1999

Early rebleeding from intracranial dural arteriovenous fistulas: report of 20 cases and review of the literature.

OBJECT: In this study the authors sought to estimate the frequency, seriousness, and delay of rebleeding in a homogeneous series of 20 patients whom they treated between May 1987 and May 1997 for arteriovenous fistulas (AVFs) that were revealed by intracranial hemorrhage (ICH). The natural history of intracranial dural AVFs remains obscure. In many studies attempts have been made to evaluate the risk of spontaneous hemorrhage, especially as a function of the pattern of venous drainage: a higher occurrence of bleeding was reported in AVFs with retrograde cortical venous drainage, with an overall estimated rate of 1.8% per year in the largest series in the literature. However, very few studies have been designed to establish the risk of rebleeding, an omission that the authors seek to remedy. METHODS: Presenting symptoms in the 20 patients (17 men and three women, mean age 54 years) were acute headache in 12 patients (60%), acute neurological deficit in eight (40%), loss of consciousness in five (25%), and generalized seizures in one (5%). Results of the clinical examination were normal in five patients and demonstrated a neurological deficit in 12 and coma in three. Computerized tomography scanning revealed intracranial bleeding in all cases (15 intraparenchymal hematomas, three subarachnoid hemorrhages, and two subdural hematomas). A diagnosis of AVF was made with the aid of angiographic studies in 19 patients, whereas it was a perioperative discovery in the remaining patient. There were 12 Type III and eight Type IV AVFs according to the revised classification of Djindjian and Merland, which meant that all AVFs in this study had retrograde cortical venous drainage. The mean duration between the first hemorrhage and treatment was 20 days. Seven patients (35%) presented with acute worsening during this delay due to radiologically proven early rebleeding. Treatment consisted of surgery alone in 10 patients, combined embolization and surgery in eight, embolization only in one, and stereotactic radiosurgery in one. Three patients died, one worsened, and in 16 (80%) neurological status improved, with 15 of 16 AVFs totally occluded on repeated angiographic studies (median follow up 10 months). CONCLUSIONS: The authors found that AVFs with retrograde cortical venous drainage present a high risk of early rebleeding (35% within 2 weeks after the first hemorrhage), with graver consequences than the first hemorrhage. They therefore advocate complete and early treatment in all cases of AVF with cortical venous drainage revealed by an ICH.

Adult↗

PubMed1999

[Preoperative direct cortical and sub-cortical electric stimulation during cerebral surgery in functional areas].

Indications of surgical treatment for lesions in functional cerebral areas depend on the ratio between the definitive neurological deficit and the beneficial effect of resection. Detection of eloquent cortex is difficult because of important individual variability. Peroperative direct cortical and subcortical electrical stimulations (DCS) provide the most precise and reliable method currently available allowing identification and preservation of neurons essential for motricity, sensitivity++ and language. We report our preliminary experience with DCS in surgery of intracerebral infiltrative tumors with a consecutive series of 15 patients operated from November 96 through September 97 in our institution. Presenting symptoms in the 15 patients (8 males, 7 females, mean age 43 years) were seizures in 11 cases (73%) and neurological deficit in 4 cases (27%). Clinical examination was normal in 11 patients and revealed hemiparesia in 4. Magnetic resonance imaging (MRI) with three-dimensional reconstruction showed a precentral tumor in 10 cases, central lesion in one patient, postcentral lesion in two cases, right insular tumor (non-dominant hemisphere) in one case. All patients underwent surgical resection using DCS with detection in 13 cases of motor cortex and subcortical pathways under genera anesthesia, in one case of somatosensory area under local anesthesia, and in one case of language areas also under local anesthesia. The tumor was recurrent in two patients had been operated earlier but without DCS. Resection, verified by postoperative MRI, was total in 12 cases (80%) and estimated at 80% in 3 patients. Histological examination revealed an infiltrative glioma in 12 cases (8 low grade astrocytomas, 3 low grade oligodendrogliomas, and one anaplastic oligodendroglioma), and metastases in 3 cases. Eight patients had no postoperative deficit, while the other 7 patients were impaired, with, in all cases except one, complete recovery in 15 days to 2 months. Direct cortical and subcortical electrical stimulations offer a reliable, precise and safe method, allowing functional mapping especially useful in case of infiltrative cerebral tumors in eloquent areas. This technique allows improvement in the quality of tumoral resection and concurrently a minimization of the risk of definitive postoperative neurological deficit.

Adult↗

PubMed1998

Three-dimensional computerized tomography in the presurgical evaluation of Chiari malformations.

Malformations of the cranio-cervical junction represent a complex entity, comprising neuro-meningeal and bone anomalies. Malformations of the central nervous system are nowadays easily explored using magnetic resonance imaging (MRI), while osseous malformations are classically assessed with standard radiographic techniques, which can give only incomplete information, and are often difficult to realize and analyse. We report a retrospective study of 10 patients with a Chiari malformation operated on in our department at La Salpêtrière hospital, between July 1995 and December 1996 (1 man, 9 women; mean of age: 35 years; postoperative median follow-up: 6 months; 70% of improvement and 20% of stabilisation), and we underline the interest of the systematic pre-operative realization of a 3D CT and angio-CT studies of the cranio-cervical junction. This examination offers advantages of: a precise analysis of the more complex osseous malformations; a study of the relationships between vascular and bony structures; a study of the relationships between neuraxis and spinal and cranial structures; and an optimal planning of the surgical procedure, adapted to the anatomical particularities of the patient.

Adolescent↗

PubMed1998

Intraoperative direct electrical stimulation of the lamina quadrigemina in a case of a deep tectal cavernoma.

Despite the recent neuro-imaging and microsurgical advances, a high rate of postoperative morbidity still remains in brain stem surgery. We report an original case of cavernous angioma of the right inferior colliculus without extension to the surface, operated on using brain stem electrical stimulations. Peroperative ocular motor responses were obtained, allowing identification of essential neural structures before dissection of the brain stem surface, and accurate definition of the limits between the lesion and functional tissue in depth. Total removal of cavernoma and surrounding gliosis was then performed, with normal postoperative neurological status. As already reported at the cortical level, peroperative direct brain stem stimulations constitute a safe and easy method of functional mapping. A more intensive use of this neurophysiological technique might permit one to extend the indications for brain stem surgery, with minimisation of postoperative morbidity and maximisation of tumour resection.

Brain Mapping↗

PubMed1998

Direct spinal cord electrical stimulations during surgery of intramedullary tumoral and vascular lesions.

Despite the use of somatosensory evoked potentials during surgery for spinal cord tumors or vascular lesions, postoperative neurological disorders, particularly motor deficits, frequently occur after aggressive surgery with an attempt of gross total resection. We report the use of peroperative direct spinal cord electrical stimulation to decrease morbidity while improving the quality of resection. Three patients with intramedullary lesions (1 ependymoma and 2 cavernomas), initially revealed by pain and followed by neurological deficit, were operated at our institution using peroperative direct medullary electrical stimulations (60 Hz, biphasic square wave pulses with 1 ms/phase, 0.9 mA) under general anesthesia without curare. In all cases, gross total resection was performed until motor responses to stimulation, which indicated anterior and lateral boundaries between the lesion and the functional tissue, were obtained. There was no postoperative neurological worsening, but an immediate partial improvement of sensory and bladder disorders in the patient with ependymoma. Postoperative MRI confirmed total resection in the 3 patients. These cases demonstrate that direct medullary electrical stimulation is a safe, easy, precise and reliable method to reduce morbidity during spinal cord surgery.

Adult↗

PubMed1997

Early radiologically proven rebleeding from intracranial cavernous angiomas: report of 6 cases and review of the literature.

Although intracranial cavernomas are known to cause haemorrhage, data concerning the frequency, severity and delay of recurrent bleedings are controversial. We report a series of 6 patients with histologically proven cavernoma, presenting with early clinical signs and radiological proof of rebleeding, that is occurring in the first month after initial overt haemorrhage. These 6 cases have been selected from a series of 142 patients seen between 1980 and 1995 in our department with cavernous angiomas or so-called AOVMs, of whom 93 presented with clinical symptoms of haemorrhage (34 patients presented symptoms of one or more rebleeding, but only 6 had radiological proof). All patients suffered neurological worsening due to the rebleeding, with an increase of the size of the haematoma on the CT scan. Five MRIs were performed at the acute stage: 3 showed evidence of cavernoma (60%). All patients underwent surgery at the acute stage of the rebleeding, with 5 improvements and 1 stabilization. A cavernous angioma was found in 5 cases at first surgery, but a further operation was necessary in the last patient to find and remove the cavernoma, after a second rebleeding following the first intervention. Our series reveals a high frequency of rebleeding after a first intracranial haemorrhage from a cavernous angioma, and highlights the precocity of such rebleedings. Therefore, we advocate early aggressive surgical management: in cases of cavernoma revealed by a first clinical overt haemorrhage, when there is strong radiological suspicion at the acute stage; and in all cases of rebleeding, even without radiological evidence of malformation, in the absence of vascular risk factors. Surgical indication must be discussed in particular cases of cavernomas of the brain stem when neither the haematoma nor the cavernoma reach the surface, and in deep supratentorial cavernomas, when the neurological status is good, because of the therapeutic risk.

Adolescent↗

PubMed1996

Tremor and voluntary repetitive movement in Parkinson's disease: comparison before and after L-dopa with positron emission tomography.

Brain regions involved in tremor and voluntary movement were compared in seven subjects with hemiparkinsonian tremor using positron emission tomography and the [15O] water bolus activation method. Repeated measurements of the regional cerebral blood flow were performed both before and after tremor arrest induced by administration of L-dopa as well as during voluntary repetitive movements of the hand contralateral to tremor side. The normalized regional cerebral blood flow (NrCBF) was measured in regions of interest with anatomical boundaries that were defined for each subject by means of a three-dimensional reconstruction of magnetic resonance imaging data. Taking the rest after L-dopa as a control condition, NrCBF increased during tremor in a network of regions including the precentral (mean +/- SD 5.36 +/- 4.6%, P = 0.006) and paracentral (6.11 +/- 6%, P = 0.01) gyri contralateral to tremor side, the supplementary motor area (SMA; 4.03 +/- 4%, P = 0.02, n = 8 pairs), and the cerebellar vermis (8.64 +/- 9.9%, P = 0.01, n = 12). During voluntary repetitive movement of the hand contralateral to tremor compared with rest after L-dopa, the same patients activated the precentral (8.25 +/- 2.6%, P = 0.0006) and postcentral regions contralateral to movement (8.43 +/- 3.7%, P = 0.002), and the cerebellar cortex (3.49 +/- 2.1%, P = 0.03), precentral (3.58 +/- 3.1%, P = 0.04), and paracentral (4.03 +/- 3.6%, P = 0.04) regions ipsilateral to movement. The cerebellar vermis was activated (8.15 +/- 5.6%, P = 0.02, n = 8) as well as the SMA, but not significantly at the 0.05 level (5.16 +/- 5%, P = 0.08, n = 5). These results confirm the similarities of brain structures involved in parkinsonian tremor and voluntary movement and provide an anatomofunctional substrate for their clinical interactions.

Aged↗

PubMedDate not supplied

[Importance of radiotherapy in stereotactic conditions (radiosurgery) in brain metastasis: experience and results of the Hôpital Pitié-Salpêtrière Group].

PURPOSE: Retrospective analysis of the influence of clinical and technical factors on local control and survival after radiosurgery for brain metastasis. PATIENTS AND METHODS: From January 1994 to December 1996, 42 patients presenting with 71 metastases underwent radiosurgery for brain metastasis. The median age was 56 years and the median Karnofsky index 80. Primary sites included: lung (20 patients), kidney (seven), breast (five), colon (two), melanoma (three), osteosarcoma (one) and it was unknown for three patients. Seventeen patients had extracranial metastasis. Twenty-four patients were treated at recurrence which occurred after whole brain irradiation (12 patients), surgical excision (four) or after both treatments (eight). Thirty-six sessions of radiosurgery have been realized for one metastasis and 13 for two, three or four lesions. The median metastasis diameter was 21 mm and the median volume 1.7 cm3. The median peripheral dose to the lesion was 14 Gy, and the median dose at the isocenter 20 Gy. RESULTS: Sixty-five metastases were evaluable for response analysis. The overall local control rate was 82% and the 1-year actuarial rate was 72%. In univariate analysis, theoretical radioresistance (P = 0.001), diameter less than 3 cm (P = 0.039) and initial treatment with radiosurgery (P = 0.041) were significantly associated with increased local control. Only the first two factors remained significant in multivariate analysis. No prognostic factor of overall survival was identified. The median survival was 12 months. Six patients had a symptomatic oedema (RTOG grade 2), only one of which requiring a surgical excision. CONCLUSION: In conclusion, 14 Gy delivered at the periphery of metastasis seems to be a sufficient dose to control most brain metastases, with a minimal toxicity. Better results were obtained for lesions initially treated with radiosurgery, theoretically radioresistant and with a diameter less than 3 cm.

Adenocarcinoma↗

PubMedDate not supplied

[First treatment for brain metastases by stereotactic radiosurgery].

Local control of brain metastases is better with first treatment by stereotactic radiosurgery than with radiosurgery for recurrence. We reported a retrospective analysis of the influence of clinical and technical factors on local control and survival after radiosurgery realised in first intention. From January 1994 to December 1997, 26 patients presenting with 43 metastases underwent radiosurgery. The median age was 61 years and the median Karnofsky index 70. Primary sites included: lung (12 patients), kidney (7 patients), breast (2 patients), colon (1 patient), melanoma (2 patients), osteosarcoma (1 patient), it was unknown for one patient. Seven patients had extracranial metastases. Twenty-one sessions of radiosurgery have been realized for one metastase, and 9 for two, three or four lesions. The median diameter was 21 mm and the median volume 1.8 cm3. The median peripheral dose to the lesion was 14 Gy, and the median dose at the isocenter 20 Gy. Forty-two metastases were evaluable for response analysis. The overall local control rate was 90.5% and the 1-year, 2- and 3-year actuarial rates were 85% and 75%. In univariate analysis, theorical radioresistance was significantly associated with better local control (100% versus 77%, p < 0.05). All patients were evaluable for survival. The median survival rate was 15 months. Four patients had a symptomatic oedema (RTOG grade II). Two lesions have required a surgical excision. In conclusion, low dose radiosurgery (14 Gy delivered at the periphery of metastasis) can be proposed in first intention for brain metastases, in particularly for theorical radioresistant lesions.

Adult↗