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H Duffau

Publications and source records attributed to H Duffau.

At least 37 records · Page 2Linked to original sources
PubMed2002

Medically intractable epilepsy from insular low-grade gliomas: improvement after an extended lesionectomy.

OBJECTIVE: With the aim to better evaluate the role of the insula in seizures and the therapeutic implications, we analyzed the rate of insular low-grade gliomas (LGG) presenting with medically refractory epilepsy, detailed their ictal symptoms, and described the epileptological results following their surgical resection. METHODS: Eleven patients (8 men, 3 women, mean age: 35 years) harboring an insular LGG generating intractable seizures, underwent tumor removal and perilesional opercular cortex resection (lesionectomy "plus") using intraoperative functional electrical mapping, combined with ultrasonography and/or neuronavigation. RESULTS: Despite the occurrence of five postoperative deficits, the patients recovered in all cases. The epileptological results showed improvement in all cases: 9 Engel's Class I (82%), 1 Class II and 1 Class III. Ten lesionectomies were total [3] or subtotal [7], while one resection was partial (the patient in Engel's III). CONCLUSION: The high rate of pharmacologically intractable seizures associated with insular LGG, and the favorable epilepsy outcome following surgical resection of these tumors seemingly indicate that the insular cortex itself may induce chronic seizures when injured. These results suggest, taking account of the technical surgical progress allowing now to minimize the morbidity after surgery in this region, that there is another indication than the sole oncological reason for surgery in patients with diffuse insular glioma -- even if total tumor removal is not systematically possible.

Adult↗
PubMed2002

Long term reshaping of language, sensory, and motor maps after glioma resection: a new parameter to integrate in the surgical strategy.

OBJECTIVES: To describe cortical reorganisation and the effects of glioma infiltration on local brain function in three patients who underwent two operations 12-24 months apart. METHODS: Three patients who had no neurological deficit underwent two operations for low grade glioma, located in functionally important brain regions. During each operation, local brain function was characterised by electrical mapping and awake craniotomy. RESULTS: Language or sensorimotor areas had been invaded by the tumour at the time of the first operation, leading to incomplete glioma removal in all cases. Because of a tumour recurrence, the patients were reoperated on between 12 and 24 months later. Functional reorganisation of the language, sensory, and motor maps was detected by electrical stimulation of the brain, and this allowed total glioma removal without neurological sequelae. CONCLUSIONS: These findings show that surgical resection of a glioma can lead to functional reorganisation in the peritumorous and infiltrated brain. It may be that this reorganisation is directly or indirectly caused by the surgical procedure. If this hypothesis is confirmed by other studies, the use of such brain plasticity potential could be used when planning surgical options in some patients with low grade glioma. Such a strategy could extend the limits of tumour resection in gliomas involving eloquent brain areas without causing permanent morbidity.

Adult↗
PubMed2002

Intraoperative mapping of the cortical areas involved in multiplication and subtraction: an electrostimulation study in a patient with a left parietal glioma.

OBJECTIVES: Advances in neuroimaging studies have recently improved the understanding of the functional anatomy of the calculation processes, having in particular underlined the central role of the angular gyrus (AG). In this study, the authors applied this knowledge to the surgical resection of a glioma invading the left AG, by localising and sparing the cortical areas involved in two different components of calculation (multiplication and subtraction), using direct electrical stimulations. METHODS: A calculation mapping was performed in a patient without deficit except a slightly impaired performance for serial arithmetic subtraction, during the resection under local anaesthesia of a left parieto-occipital glioma invading the dominant AG. After somatosensory and language mappings, cortical areas involved in single digit multiplications and subtractions of seven were mapped using the method of electrostimulation, before glioma removal. RESULTS: Distinct sites specifically involved in multiplication or subtraction were detected within the left AG, with a precise spatial distribution and overlapping. All the eloquent (somatosensory, language, and calculation) areas were surgically spared. Postoperatively, the patient had a transient complete deficit for arithmetic subtraction, without either multiplication or language disturbance. The tumour removal was complete. CONCLUSIONS: These findings suggest: firstly, the usefulness of an intraoperative calculation mapping during the removal of a lesion involving the left dominant AG, to avoid permanent postoperative deficit of arithmetic processes while optimising the quality of tumour resection; secondly, the possible existence of a well ordered and dynamic anatomo-functional organisation for different components of calculation within the left AG.

Adult↗
PubMed2002

[Surgery of intracranial epidermoid cysts. Report of 44 patients and review of the literature].

Forty-four patients (22 males and 22 females) were admitted to our institution for an intracranial epidermoid cyst between 1980 and 2000. Their mean age was 39.9 years. The duration of the disease at admission varied between a few days and 30 years. CT-scan was performed in all cases, MRI in 33 cases with a diffusion sequence in 3. Most of the 26 patients with posterior fossa lesions were treated surgically in the sitting position, with resection of the tonsils in four cases in order to minimize cerebellar retraction. The other supratentorial tumors were operated using a fronto-temporo-pterional approach in 13 cases (with temporo-polar lobectomy in 6 cases), or a parietal transparenchymal approach in the parieto-occipital lesions (2 cases). The resection was total or subtotal (residual capsule) in 79.5% of cases. Post-operative morbidity was 13.6% and mortality 8.9%. The median follow-up was 8 years, with a recurrence rate of 4.5%. Epidermoid cysts are benign, slowly but ineluctably growing tumors which require surgical treatment. Their diagnosis has become easier, especially with the development of MRI diffusion sequences. Morbidity and mortality (morbi-mortality) reported in the literature as well as found in our series seems to be unrelated to classical aseptic meningitis (22.7% in our series) or hydrocephalus (2 cases in our series). For many authors, it may be the consequence of systematic resection of the tumor capsule. This does not seem to be the case in our series in which only 25% of the patients underwent a complete resection. Prolonged cerebral retraction could be one of the responsible factors. One of the technical proposals could be to perform a transparenchymal approach in selected patients.

Adult↗
PubMed2002

[Proposing surgical management to a patient with low-grade glioma: controversies and ethical consequences].

The therapeutic controversies surrounding low-grade glioma result mainly from the lack of certainty about their histological definition, and, from our imperfect knowledge of the natural history of the disease. Heterogeneous surgical management is the consequence of this situation, which renders difficult to propose the best attitude to each individual patient, thus raising ethical questions, because the absence of a consensus. Performing prospective studies able to analyse these different modalities is mandatory whenever we want to be enable to give to our patients the best answer in their precise case, and furthermore to justify back our acts too.

Attitude of Health Personnel↗
PubMed2001

Role of the supplementary motor area in motor deficit following medial frontal lobe surgery.

OBJECTIVE: Patients undergoing surgical resection of medial frontal lesions may present a transient postoperative deficit that remains largely unpredictable. The authors studied the role of the supplementary motor area (SMA) in the occurrence of this deficit using fMRI. METHODS: Twenty-three patients underwent a preoperative fMRI before resection of medial frontal lesions. Tasks included self-paced flexion/extension of the left and right hand, successively. Preoperative fMRI data were compared with postoperative MRI data and with neurologic outcome. RESULTS: Following surgery, 11 patients had a motor deficit from which all patients recovered within a few weeks or months. The deficit was similar across patients, consisting of a global reduction in spontaneous movements contralateral to the operated side with variable severity. SMA activation was observed in all patients. The deficit was observed when the area activated in the posterior part of the SMA (SMA proper) was resected. CONCLUSIONS: fMRI is able to identify the area at risk in the SMA proper whose resection is highly related to the occurrence of the motor deficit. The clinical characteristics of this deficit support the role of the SMA proper in the initiation and execution of the movement.

Adult↗
PubMed2001

Functional compensation of the left dominant insula for language.

The left dominant insula was recently described as an essential area of speech, inducing definitive language disturbances when injured. We describe a patient with mild dysphasia, harboring a left insular glioma. A functional MRI found activations within the left inferior and middle frontal gyri, superior temporal gyrus, basal ganglia, but not in the insula. Surgery was performed using intraoperative electrical mapping in the awake patient, identifying the same language sites as showed by fMRI. A complete glioma resection was then performed. Despite an entire dominant insula removal, the patient presented no postoperative deficit, and even recovered from the preoperative dysphasia. This case illustrates the brain ability to maintain normal language without the left insula. The mechanisms of compensation are discussed.

Adult↗
PubMed2001

Radiosurgery for re-irradiation of brain metastasis: results in 54 patients.

PURPOSE: To evaluate in terms of probabilities of local-regional control and survival, as well as of treatment-related toxicity, results of radiosurgery for brain metastasis arising in previously irradiated territory. PATIENTS AND METHODS: Between January 1994 and March 2000, 54 consecutive patients presenting with 97 metastases relapsing after whole brain radiotherapy (WBRT) were treated with stereotactic radiotherapy. Median interval between the end of WBRT and radiosurgery was 9 months (range 2-70). Median age was 53 years (24-80), and median Karnofski performance status (KPS) 70 (60-100). Forty-seven patients had one radiosurgery, five had two and two had three. Median metastasis diameter and volume were 21 mm (6-59) and 1.2 cc (0.1-95.2), respectively. A Leksell stereotactic head frame (Leksell Model G, Elektra, Instrument, Tucker, GA) was applied under local anesthesia. Irradiation was delivered by a gantry mounted linear accelerator (linacs) (Saturne, General Electric). Median minimal dose delivered to the gross disease was 16.2 Gy (11.8-23), and median maximal dose 21.2 Gy (14- 42). RESULTS: Median follow-up was 9 months (1-57). Five metastases recurred. One- and 2-year metastasis local control rates were 91.3 and 84% and 1- and 2-year brain control rates were 65 and 57%, respectively. Six patients died of brain metastasis evolution, and three of leptomeningeal carcinomatosis. One- and 2-year overall survival rates were 31 and 28%, respectively. According to univariate analysis, KPS, RPA class, SIR score and interval between WBRT and radiosurgery were prognostic factors of overall survival and brain free-disease survival. According to multivariate analysis, RPA was an independent factor of overall survival and brain free-disease survival, and the interval between WBRT and radiosurgery longer than 14 months was associated with longer brain free-disease survival. Side effects were minimal, with only two cases of headaches and two of grade 2 alopecia. CONCLUSION: Salvage radiosurgery of metastasis recurring after whole brain irradiation is an effective and accurate treatment which could be proposed to patients with a KPS>70 and a primary tumour controlled or indolent. We recommend that a dose not exceeding 14 Gy should be delivered to an isodose representing 70% of the maximal dose since local control observed rate was similar to that previously published in literature with upper dose and side effects were minimal.

Adult↗
PubMed2001

Acute functional reorganisation of the human motor cortex during resection of central lesions: a study using intraoperative brain mapping.

OBJECTIVES: Brain plasticity is supposed to allow the compensation of motor function in cases of rolandic lesion. The aim was to analyse the mechanisms of functional reorganisation during surgery in the central area. METHODS: A motor brain mapping was performed in three right handed patients without any neurological deficit, operated on for a slow growing lesion near the rolandic region (two precentral resected under general anaesthesia and one retrocentral removed under local anaesthesia to allow also sensory mapping) using intraoperative direct electrical stimulations (5 mm space tips bipolar stimulator probe, biphasic square wave pulse current: 1 ms/phase, 60 Hz, 4 to 18 mA). RESULTS: For each patient, the motor areas of the hand and forearm in the primary motor cortex (M1) were identified before and after lesion removal with the same stimulation parameters: the same eloquent sites were found, plus the appearance after resection of additional sites in M1 inducing the same movement during stimulations as the previous areas. CONCLUSIONS: Multiple cortical representations for hand and forearm movements in M1 seem to exist. In addition, the results demonstrate the short term capacity of the brain to make changes in local motor maps, by sudden unmasking after tumour resection of a second redundant site participating in the same movement. Finally, it seems not necessary for the whole of the redundant sites to be functional to provide normal movement, a concept with potential implications for surgery within the central region.

Adult↗
PubMed2001

Delayed onset of the supplementary motor area syndrome after surgical resection of the mesial frontal lobe: a time course study using intraoperative mapping in an awake patient.

Although the occurrence of the supplementary motor area (SMA) syndrome has been extensively reported following mesial lobe surgery, to our knowledge the time course of disease onset was never accurately documented. We describe a patient without deficit, despite harboring a glioma invading the left SMA. This patient was operated under local anesthesia, to perform intraoperative online sensorimotor and language mapping using electrical stimulations throughout the resection. No deficit was noted at the end of the tumor and SMA removal. The patient was maintained awake to perform an immediate control MRI. Aphasia and right hemiplegia occurred 30 min after the SMA resection. Total recovery was observed within 2 months. This work shows that the SMA syndrome may not occur immediately after SMA resection. We suggest that the transient compensation of the SMA function is likely due to residual activity of an oscillatory loop and/or short-term plasticity (rapid unmasking of parallel networks), with final recovery occurring due to long-term plasticity (neosynaptogenesis).

Adult↗
PubMed2001

Recovery from complete hemiplegia following resection of a retrocentral metastasis: the prognostic value of intraoperative cortical stimulation.

The goal in this study was to determine if intraoperative electrical stimulation mapping is useful during surgical resection of lesions located in the central region, even in cases of preoperative hemiplegia. This 45-year-old man with a retrocentral metastasis from an embryonal carcinoma of the testis suffered an acute complete hemiplegia after intratumoral bleeding. Emergency surgery was performed with the aid of intraoperative motor mapping despite the preoperative deficit. Cortical stimulations (CSs) elicited motor responses, allowing the detection and hence preservation of the primary motor area during tumor removal. Postoperatively, the patient recovered almost completely within 1 week; the tumor resection was total. It is possible that CSs give an early and valuable prognostic indicator of motor recovery in cases of complete hemiplegia, at least in patients with acute onset and short duration of the deficit. Consequently, if motor responses can be elicited by CSs, it becomes mandatory for the surgeon to respect the primary motor area despite the preoperative hemiplegia, with the aim of preserving the chances of an eventual recovery.

Brain Neoplasms↗
PubMed2001

[Functional recuperation after resection of gliomas infiltrating primary somatosensory fields. Study of perioperative electric stimulation].

BACKGROUND: With the aim to achieve the most complete resection in cases of parietal low-grade glioma involving the primary somatosensory area (S I), the authors describe a series with resection of S I using an intraoperative brain mapping. The immediate and delayed postoperative functional results are analyzed. PATIENTS AND METHODS: Six patients were operated on for a low-grade glioma involving S I, revealed by seizures with a normal clinical examination. All patients underwent awake surgery under local anesthesia, to allow realization of an intraoperative sensorimotor brain mapping using direct electrical stimulations. RESULTS: The primary motor area (M I) and S I were detected in all procedures. A part of infiltrated S I was removed in spite of a sensitive response of this area during stimulations (sensory face in 2 cases, upper limb area in 5 cases, and lower limb area in 2 cases). All patients presented an immediate postoperative sensory deficit, with recovery in the 6 cases within 3 months. Five resections were total and one subtotal. CONCLUSIONS: In our experience, the primary somatosensory area could be resected in case of tumoral infiltration, without inducing a permanent neurological deficit. This may be due to brain plasticity mechanisms, with recruitment of loco-regional and controlateral eloquent regions, and also the learning of new compensatory strategies. Such a phenomenon can lead to perform more extensive resections in cases of infiltrative gliomas in the somatosensory region.

Adult↗
PubMed2001

[Functional recuperation following lesions of the primary somatosensory fields. Study of compensatory mechanisms].

During a long time, lesions of the primary somatosensory area (S I) were considered as generating severe and definitive neurological sequelae. However, recent reports described a recovery following stroke and resective surgeries (for epilepsy or tumor). On the basis of these observations, of experimentations in animals, and of studies of the (re)organization of eloquent areas in man using new methods of functional mapping, brain plasticity phenomena underlying the recovery were analyzed. They seems to implicate the recruitment of local areas (sensory redundancies within S I), regional areas (primary motor area, secondary somatosensory area, posterior parietal cortex, insula), controlateral eloquent regions, and even learning of new compensatory strategies. Such data could allow us to extend surgical indications of resection of lesions located within S I. An improvement of our knowledge of these functional reshaping phenomena (unmasking of latent networks and/or participation of eloquent homologous and/or sprouting) and then their prediction remains mandatory, with the goal to optimize the surgical preplanning in functional regions, taking account of the individual dynamic spatiotemporal cortical organization. This better knowledge seems to be obtained by studying the correlations between pre- and post-operative functional neuroimaging (fMRI, MEG) data, and the intraoperative functional mapping results.

Animals↗
PubMed2000

Primary intradural extramedullary ependymoma: case report and review of the literature.

STUDY DESIGN: The authors report the ninth case in the literature of a primary intradural extramedullary ependymoma of the spinal cord. OBJECTIVE: To discuss surgical treatment and the physiopathologic hypothesis of this localization on the basis of the results of the present study and a review of the literature. SUMMARY OF BACKGROUND DATA: Ependymoma is a glial tumor known to arise in the central nervous system. Intradural extramedullary location of this neoplasm has been exceptionally described previously. METHODS: A 43-year-old woman was admitted to the authors' institution with an history of progressive paraplegia. Neurologic examination showed sensory loss below T1 and bladder disturbances. Magnetic resonance imaging revealed an enhanced thoracic intradural extramedullary tumor, extending from T1-T8. No other lesion in the central nervous system was found. Emergency surgical resection was performed. RESULTS: Surgery gave confirmation of an encapsulated extramedullary tumor without attachment to the spinal cord or to the dura mater. Total removal was achieved under microscope. The postoperative course was uneventful, with complete neurologic recovery 3 months later. The patient has been well for 24 months of follow-up evaluation, without evidence of recurrence on magnetic resonance images. Histologic examination revealed the tumor as a benign ependymoma. CONCLUSION: The encapsulated feature, the lack of attachment to the central nervous system, and the absence of other neoplastic processes within the brain or the spinal cord suggested that this lesion is a primary tumor developed from ectopic ependymal cells.

Adult↗
PubMed2000

Intraoperative direct subcortical stimulation for identification of the internal capsule, combined with an image-guided stereotactic system during surgery for basal ganglia lesions.

BACKGROUND: The two main problems of surgery for basal ganglia lesions are: first, the difficulty of accurately localizing the lesion in this deep location; and second, the proximity to the internal capsule, with the risk of permanent postoperative sequelae. The author describes the use of intraoperative direct electrical subcortical stimulation in the identification and preservation of the internal capsule, combined with an image-guided stereotactic system for the selection of the best surgical approach in a case of deep cavernoma. CASE DESCRIPTION: A 33-year-old man was admitted to our institution with a history of three episodes of transitory left hemiparesia in the last 12 years. Neurological examination revealed a mild left weakness. Magnetic resonance imaging (MRI) showed typical features of a right posterior capsular-lentiform cavernoma. To prevent another hemorrhagic event, surgery was performed via a right transdistal sylvian approach, using a computer-assisted stereotactic method that allowed us to reach the lesion directly and direct stimulations to detect the subcortical pyramidal pathways. The patient had a transitory worsening with complete recovery in 10 days. Control MRI showed total resection. CONCLUSION: As described at the cortical level, the intraoperative direct subcortical stimulations seem also to represent an easy, safe, accurate, and reliable method of real-time functional identification of the internal capsule during surgery for basal ganglia lesions. The combination with an image-guided stereotactic system to accurately localize the lesion minimizes the risk of postoperative sequelae, and seems to warrant an increase of the surgical indications in this location.

Adult↗
PubMed2000

The insular lobe: physiopathological and surgical considerations.

OBJECTIVE: Surgery of the insula represents a technical challenge, because of the proximity of the internal capsule to the lenticulostriate arteries and the lack of certainty concerning its functionality. Using intraoperative direct cerebral stimulation, combined with neuronavigation, the authors operated on 12 insular gliomas. On the basis of this experience, the physiopathological and surgical implications are discussed. METHODS: A low-grade insular glioma, revealed by seizures, was diagnosed in 12 right-handed patients with a normal neurological status. Preoperative magnetic resonance imaging showed that, according to Yasargil's classification system, three patients harbored Type 3 lesions and nine patients had Type 5 lesions (10 tumors on the right side and 2 on the left dominant side). All patients underwent surgery using direct cerebral stimulation, under general anesthesia in nine patients (motor mapping) and under local anesthesia in three patients (sensorimotor and language mapping). Ultrasonography and/or neuronavigation was used in all cases. Preoperative angio-computed tomographic scanning showed the lenticulostriate arteries in two patients. RESULTS: The internal capsule was systematically detected, and the language areas were identified within the left insula in the awake patients. The lenticulostriate arteries were seen in two patients. Seven patients presented an immediate postoperative deficit; six of them recovered completely within 3 months. Four resections were total, six were subtotal, and two were partial (left insula). CONCLUSION: The use of intraoperative direct cerebral stimulation and neuronavigation allows surgery of the insula with minimization of the risk of sequelae, but its use is still limited with regard to the dominant hemisphere, owing to the essential role of this structure in language.

Adult↗
PubMed2000

Correspondence between functional magnetic resonance imaging somatotopy and individual brain anatomy of the central region: comparison with intraoperative stimulation in patients with brain tumors.

OBJECT: The goal of this study was to determine the somatotopical structure-function relationships of the primary motor cortex in individual patients by using functional magnetic resonance (fMR) imaging. This was done to assess whether there is a displacement of functional areas compared with anatomical landmarks in patients harboring brain tumors close to the central region, and to validate these findings with intraoperative cortical stimulation. METHODS: One hundred twenty hemispheres in 60 patients were studied by obtaining blood oxygen level-dependent fMR images in patients while they performed movements of the foot, hand, and face on both sides. There was a good correspondence between anatomical landmarks in the deep portion of the central sulcus on axial slices and the somatotopical organization of primary motor areas. Pixels activated during hand movements were centered on a small characteristic digitation; those activated during movements in the face and foot areas were located in the lower portion of the central sulcus (lateral to the hand area) and around the termination of the central sulcus, respectively. In diseased hemispheres, signal-intensity changes were still observed in the projection of the expected anatomical area. The fMR imaging data mapped intraoperative electrical stimulation in 92% of positive sites. CONCLUSIONS: There was a high correspondence between the somatotopical anatomy and function in the central sulcus, which was similar in normal and diseased hemispheres. The fMR imaging and electrical stimulation data were highly concordant. These findings may enable the neurosurgeon to locate primary motor areas more easily during surgery.

Adult↗