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P Frerebeau

Publications and source records attributed to P Frerebeau.

At least 19 recordsLinked to original sources
PubMed2004

Mutations within the MGC4607 gene cause cerebral cavernous malformations.

Cerebral cavernous malformations (CCM) are hamartomatous vascular malformations characterized by abnormally enlarged capillary cavities without intervening brain parenchyma. They cause seizures and focal neurological deficits due to cerebral hemorrhages. CCM loci have already been assigned to chromosomes 7q (CCM1), 7p (CCM2), and 3q (CCM3) and have been identified in 40%, 20%, and 40%, respectively, of families with CCM. Loss-of-function mutations have been identified in CCM1/KRIT1, the sole CCM gene identified to date. We report here the identification of MGC4607 as the CCM2 gene. We first reduced the size of the CCM2 interval from 22 cM to 7.5 cM by genetic linkage analysis. We then hypothesized that large deletions might be involved in the disorder, as already reported in other hamartomatous conditions, such as tuberous sclerosis or neurofibromatosis. We performed a high-density microsatellite genotyping of this 7.5-cM interval to search for putative null alleles in 30 unrelated families, and we identified, in 2 unrelated families, null alleles that were the result of deletions within a 350-kb interval flanked by markers D7S478 and D7S621. Additional microsatellite and single-nucleotide polymorphism genotyping showed that these two distinct deletions overlapped and that both of the two deleted the first exon of MGC4607, a known gene of unknown function. In both families, one of the two MGC4607 transcripts was not detected. We then identified eight additional point mutations within MGC4607 in eight of the remaining families. One of them led to the alteration of the initiation codon and five of them to a premature termination codon, including one nonsense, one frameshift, and three splice-site mutations. All these mutations cosegregated with the disease in the families and were not observed in 192 control chromosomes. MGC4607 is so far unrelated to any known gene family. Its implication in CCMs strongly suggests that it is a new player in vascular morphogenesis.

Female↗
PubMed2001

[Neurosurgical treatment of hyperactive bladder in spinal cord injury patients].

OBJECTIVES: We report long-term results of posterior sacral root rhizotomies in combination with Finetech-Brindley anterior sacral root stimulators implanted intradurally in 20 spinal cord injury patients. MATERIAL: and methods: The 14 female and 6 male patients included 14 paraplegics and 6 tetraplegics. All of them initially presented hyperactive bladder, detrusor-sphincter dyssynergia, recurrent urinary tract infection and performed (self) intermittent catheterization. Prior to implantation, an intrathecal test using bupivacaine was performed to confirm the compliances of the bladder. The main indication for implantation was persistent urinary incontinence refractory to medical therapy. RESULTS: After implantation the mean follow-up was 4,5 years. In all, 18 patients used the stimulator alone for bladder emptying and 18 patients were completely continent. The mean bladder capacity increased from 190 ml preoperatively to 460 ml after the operation. The mean residual urinary volume was reduced from 90 ml to 25 ml. No changes were noted by renal isotopic scanning in upper urinary tracts of patients. In 1 patient, a second extradural implant was performed. DISCUSSION: This article also include an overview of a) the different available sites where application of electrical stimulation results in a detrusor contraction, b) the benefits and disadvantages of the sacral posterior rhizotomy, c) selective stimulation techniques that allow selective detrusor activation by sacral root stimulation. CONCLUSION: Sacral anterior root stimulation combined with sacral posterior rhizotomy is a valuable method to restore bladder functions in spinal cord injured patients suffering from hyperactive bladder refractory to medical therapy.

Adolescent↗
PubMed2000

Magnetic resonance imaging stereotactic target localization for deep brain stimulation in dystonic children.

OBJECT: The actual distortion present in a given series of magnetic resonance (MR) images is difficult to establish. The purpose of this study was to validate an MR imaging-based methodology for stereotactic targeting of the internal globus pallidus during electrode implantation in children in whom general anesthesia had been induced. METHODS: Twelve children (mean follow up 1 year) suffering from generalized dystonia were treated with deep brain stimulation by using a head frame and MR imaging. To analyze the influence of distortions at every step of the procedure, the geometrical characteristics of the frame were first controlled using the localizer as a phantom. Then pre- and postoperative coordinates of fixed anatomical landmarks and electrode positions, both determined with the head frame in place, were statistically compared. No significant difference was observed between theoretical and measured dimensions of the localizer (Student's t-test, ¿t¿ > 2.2 for 12 patients) in the x, y, and z directions. No significant differences were observed (Wilcoxon paired-sample test) between the following: 1) pre- and postoperative coordinates of the anterior commissure (AC) (deltax = 0.3+/-0.29 mm and deltay = 0.34+/-0.32 mm) and posterior commissure (PC) (deltax = 0.15+/-0.18 mm and deltay = 0.34+/-0.25 mm); 2) pre- and postoperative AC-PC distance (deltaL = 0.33+/-0.22 mm); and 3) preoperative target and final electrode position coordinates (deltax = 0.24+/-0.22 mm; deltay = 0.19+/-0.16 mm). CONCLUSIONS: In the authors' center, MR imaging distortions did not induce detectable errors during stereotactic surgery in dystonic children. Target localization and electrode implantation could be achieved using MR imaging alone after induction of general anesthesia. The remarkable postoperative improvement in these patients confirmed the accuracy of the procedure (Burke-Marsden-Fahn Dystonia Rating Scale score delta = -83.8%).

Adolescent↗
PubMed1999

[Intra-orbital decompression of the optic nerve by opening the peri-optic meninges in the treatment of severe optic neuropathies complicating benign intracranial hypertension].

Papilledema from benign intracranial hypertension can cause severe loss of visual acuity and visual field, with an optic neuropathy. We report a study of 5 patients with benign intracranial hypertension, and severe visual loss (visual field loss and visual acuity reduced to 1/10 or less) not improved by medical therapy (acetazolamide). We performed unilateral orbital decompression of the optic nerve sheath. No major operative complication was noted. Follow-up ranged from 11 months to 23 months, with an average of sixteen months. Visual function improvement was noted within 3 months after operation in 4 patients (for 2 eyes on the surgical side improvement of 2/10 and 5/10, for 3 eyes on the opposite surgical side average improvement of 4.6/10). The other patient showed improvement, but no significant. Optic nerve sheath decompression in benign intracranial hypertension seems to be a safe procedure and a therapeutic option in the management of raised intracranial pressure complicated by optic neuropathy with severe visual loss.

Acetazolamide↗
PubMed1999

[Treatment of early-onset generalized dystonia by chronic bilateral stimulation of the internal globus pallidus. Apropos of a case].

Dystonia musculorum deformans is an inherited severe disease, with a wide clinical polymorphism. The most severe clinical forms with early onset carry a high risk of life-threatening complications. In the absence of any efficient medical treatment, bilateral pallidotomy has previously been reported to be of value in the management of this disease. We report the first clinical case of a severe early-onset generalized dystonia dramatically improved by a bilateral stimulation of the internal globus pallidus. In November 1996, we proposed this neurosurgical procedure for a 8-year-old girl, who had suffered since the age of 3 from severe generalized dystonia, and who progressively became totally dependent and bedridden. She had been under sedation and permanent controlled respiratory assistance for the last two months. The etiology of the disease remained unknown (the DYT1 mutation was absent). Under general anesthesia, we bilaterally implanted a four-contacts electrode in the internal globus pallidus, using the Leksell's stereotactic frame and a 1.5 tesla MRI control. A dramatic improvement was noted 6 weeks later and led us to connect the two electrodes to neurostimulators inserted under the abdominal skin.

Age of Onset↗
PubMed1998

Anatomic basis for the treatment of aneurysms of the upper cervical segment of the internal carotid artery by extra-intracranial cervico-petrous bypass with inverted "in situ" saphenous vein graft.

In the surgical treatment of aneurysms of the upper cervical portion of the internal carotid a., exclusion of the affected vascular segment combined with an extra-anatomic cervico-petrous bypass using a vein graft (great saphenous v.) may be considered. One of the problems specific to these extra-anatomic bypasses is associated with the sub-cutaneous positioning of the vein graft, exposing it to risks of angulation, torsion or extrinsic compression that may lead to early venous thrombosis. We suggest an alternative technique using the principle of telescoping and consisting of positioning the vein graft within the cervical portion of the artery ("in situ" bypass). The cervical portion of the ICA may be used as a tunnel for the vein graft since there are no collateral arterial branches at this level. The technical features of such a bypass are defined by means of an anatomo-surgical study in the cadaver: exposure of the petrous portion of the internal carotid a. in its horizontal segment by subtemporal access, exposure of the ICA in the neck, transverse arteriotomies of the ICA, angioplasty with a Fogarty balloon, intracarotid telescoping of a saphenous vein graft from the cervical to the petrous region, distal end-to-end anastomosis between the vein graft and the petrous portion of the ICA, and proximal end-to-end anastomosis between the vein graft and the cervical portion of the ICA.

Cadaver↗
PubMed1998

[Cyst of the conus masquerading as motor neuron disease].

We report on a patient presenting with rapidly progressive painless paraplegia, amyotrophy and fasciculations masquerading as motoneuron disease. There were no bowel or bladder involvement but the patient noted mild paresthesia on the external part of the right foot and hypertrophy of the right calve was present. While lumbar CT Scan was normal, MRI showed a large cyst of the conus. Analysis of the cyst concluded to a benign cyst of the conus. Paraplegia resolved after surgery and after one year, no relapse was observed so that an hidden ependymoma appeared unlikely.

Cauda Equina↗
PubMed1997

[Ectopic intraspinal extradural anaplastic ependymoma in an infant].

BACKGROUND: Ependymomas represent about 10% of the spinal tumors in children. Some of them may be unusually located. CASE REPORT: A 10-month-old boy was admitted for an abdominal mass syndrome with dehydration asthenia and acute bladder dysfunction. A few hours later, he developed a flaccid paraplegia. Ultrasonic and magnetic resonance spinal imaging showed a giant intraspinal tumor extending from T9 to IA level, posteriorly located to the dural compartment, widening the spinal cord. Ultrasonography also showed right ureterohydronephrosis due to the neurological bladder dysfunction. A conservative laminotomy-laminoplasty was performed in emergency. Total removal of the tumor that was attached to the right dorsal root was achieved extradurally, requiring resection of the proximal part of the root. Histological features were typical of malignant ependymoma. Chemotherapy was initiated 2 weeks later. The severe renal destruction and the persistent bladder dysfunction led to a heminephrectomy and a cystostomy, 3 weeks later. The neurological recovery was only partial with a follow-up of 18 months. CONCLUSION: Ectopic intraspinal extradural localization of ependymomas is rare and their development from a nerve root is exceptional.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

[Symptomatic aneurysms of the postero-inferior cerebellar artery. A multicenter retrospective study of 29 cases].

A multicenter retrospective study of 29 cases of posterior inferior cerebellar artery is reported. Over a period of 21 years, the frequency of posterior inferior cerebellar artery aneurysm among all intracranial aneurysm was estimated to 1.38 p. 100 of cases of aneurysms followed by 3 University Hospitals. Frequency of rupture appeared to be very high (93 p. 100) in this series probably because of the type of selection. Average grade of presentation according to Hunt and Hess classification being < III in 3 fourth of the cases. Neither clinical presentation nor suspicious etiological factors were specific of this localization. Only two cases were of pseudotumoral appearance. Positive diagnosis of subarachnoid hemorrhage was made by CT scan. Angiograms gave diagnosis of localization of the malformation and its type. Intraventricular hemorrhage was found in 62 p. 100 of our cases: all had hemorrhage of the fourth ventricle. Hydrocephaly was more frequent as compared to supratentorial localizations, Vasospasm was less frequent as in supratentorial localizations. Nimodipin seems to be efficient. Therapeutic possibilities are primary dominated by surgery with good results when it is possible. Endovascular treatment is under evaluation.

Adult↗
PubMed1996

Total endovascular occlusion of a giant direct arteriovenous fistula in the posterior fossa in a case of Rendu-Osler-Weber disease.

We report a case of giant single-hole direct arteriovenous fistula (AVF) located in the posterior fossa of a child with Rendu-Osler-Weber disease (ROW). There is neither a clinical nor an angioarchitectural difference between AVFs associated with ROW and sporadic AVFs, but ROW should be suspected in children with multifocal pial AVFs. Transarterial embolization was performed to obliterate the AVF in a unique procedure using simultaneous bifemoral catheterization. At follow up 4 years later, the clinical examination was normal. Control MR scans and angiography showed the total occlusion of the fistula, permanent thrombosis of the venous pouch, and disappearance of the abnormal venous drainage. In this case, the endovascular procedure was available and we estimated that it represented a lesser risk than the surgical approach (risk of hemorrhage and risk of thrombosis involving the feeding arteries and the brain stem venous drainage). Furthermore, it avoids craniotomy and reduces the duration of hospitalization.

Adolescent↗
PubMed1996

Cervical-to-petrous internal carotid artery saphenous vein in situ bypass for the treatment of a high cervical dissecting aneurysm: technical case report.

OBJECTIVE AND IMPORTANCE: We describe a novel cervical-to-petrous internal carotid artery (ICA) saphenous vein in situ bypass for the treatment of a high cervical dissecting aneurysm. The cervical ICA has no major collateral branches and can be used as a tunnel for the vein graft. CLINICAL PRESENTATIONS: A 25-year-old man was involved in a car accident. A cerebral angiogram revealed a right ICA dissection with aneurysm formation at the C1-C2 level. The patient recovered fully and was anticoagulated. Six months after the initial angiogram, a second angiogram disclosed ICA stenosis (80%) and persistence of the traumatic dissecting aneurysm. Definitive surgical bypass was considered the most appropriate course of action. TECHNIQUE: The horizontal portion of the petrous ICA was exposed by an extradural subtemporal approach. The cervical arteries were exposed by a separate surgical incision. After dividing the petrous ICA and the cervical ICA, the cervical ICA was dilated using a Fogarty balloon embolectomy catheter. A saphenous vein graft was inserted inside the lumen of the cervical ICA and was anastomosed to the ICA end-to-end both proximally and distally (cervical-to-petrous ICA in situ bypass). The graft was patent on the follow-up angiogram. CONCLUSION: We describe a new technique that could be considered an alternative to the classical extra-anatomic cervical-to-petrous ICA bypass procedures.

Adult↗
PubMed1996

[Sub-temporal supra-petrous approach to the horizontal portion of the sub-petrous internal carotid artery. Technique, indications, incidents and accidents].

Cavernous sinus exploration, anterior middle fossa transpetrous approach, and saphenous vein graft bypass require proximal control of the horizontal segment of the petrous internal carotid artery. Exposing the petrous portion of the internal carotid artery is not without the potential for serious complications (cochlea, facial nerve, auditory tube, musculus tensor tympani). With guidance from the classicaly landmarks within Glasscock's triangle, the bony petrous carotid canal can be unroofed. The authors describe an alternative method for obtaining direct vascular control under the trigeminal ganglion, safety unroofing of the carotid canal and control of the posterior face of the carotid bend. The indications, advantages, and disadvantages of this approach are described in details, along with its use in seven patients.

Carotid Artery, Internal↗
PubMed1995

Monitoring sodium methohexital distribution with [99mTc]HMPAO with single photon emission computed tomography during Wada test.

Twenty-five consecutive patients being considered for surgery for intractable epilepsy had intracarotid sodium methohexital procedures (ISM) as part of their evaluation. The lipophilic brain SPECT agent, [99mTc]hexamethylpropylene aminoxime (HMPAO), was administered intravenously during the procedure to determine the intracerebral distribution of methohexital. The validity of the ISM depends on consistent delivery of the anesthetizing agent to one hemisphere, including the mesial structures of the temporal lobe. To prevent postoperative language and memory deficits, correct interpretation of the test results supposes a reliable knowledge of which regions of the brain have been anesthetized. Currently, no absolute criteria allow determination of the level and topographical extent of the anesthesia. We compared results of HMPAO-SPECT with clinical and EEG video-monitoring data and with results of digital subtraction angiography (DSA) performed during the test. In all patients, the effect of SM was ipsilateral cerebral hypoperfusion on SPECT and crossed cerebellar diaschisis. The distribution of HMPAO varied from patient to patient. The delivery of SM to mesial temporal lobe structures was not constant. Using nonparametric tests, we demonstrated a statistically significant relationship between hypoperfusion on SPECT and duration of hemiplegia but not with the duration of aphasia. Hypoperfusion on SPECT was also related to the onset and duration of drug-induced delta activity on EEG. SPECT showed a statistically different distribution of SM in the brain from that predicted with DSA. We present our experience with HMPAO-SPECT use for mapping the distribution of methohexital's effects during the ISM (Wada test). We confirm the results of previous studies that SPECT assessment may be an excellent way of determining the distribution of barbiturate during the examination. It increases confidence in interpreting results of speech and memory testing by detecting either contralateral diffusion of the drug due to crossflow between hemispheres or insufficient quantitative delivery to the homolateral hemisphere.

Adult↗
PubMed1994

[Bacterial abscesses of the spinal cord. Review of the literature (73 cases)].

Intramedullary spinal cord abscesses are an uncommon entity with 73 cases reported in the literature; the first case was reported in 1830. Sixty-seven percent of abscesses occur in the first 4 decades of life. Staphylococcus and Streptococcus are the most common organisms; 25% of patients have negative intraoperative cultures. The primary source of the infection could be found, in only 45% of patients. Most of these infections are secondary to metastatic spread from infections of the lung, endocarditis, genitourinary tract; 10 reports have described an intramedullary abscess secondary to a dermal sinus. The signs and symptoms depend on the location of the lesion; the thoracic spine is the most commonly area involved. Patients are usually divided into three clinical groups; acute onset (symptoms less than 1 wk), subacute onset (symptoms up to 6 wk), and chronic course (symptoms more than 6 wk). Patients with the acute form are more likely to have a fever and an elevated white blood cell count and may show either a partial or complete transverse myelitis picture. The patients with chronic abscesses are less likely to have fever and leukocytosis, and their symptoms often mimic those of an intramedullary spinal tumour. The erythrocyte sedimentation rate tends to be elevated in all patients regardless of their clinical findings. CSF cultures are usually sterile. Plain x-rays of the spine are often normal. A myelogram in conjunction with a computed tomographic scan may show the intramedullary lesion. MRI studies usually demonstrate intramedullary lesions with exceptional clarity; the use of gadolinium with T1-weighted MRI studies enhances the abscess wall.(ABSTRACT TRUNCATED AT 250 WORDS)

Abscess↗
PubMed1994

[Neurosurgical treatment of intracranial aneurysms].

This text summarizes the course organized for residents and trainees by the Société de Neurochirurgie de Langue Française. It was presented by the authors during the annual winter meeting held in Paris in December 1992. The aim of this course was to discuss all the technical points needed to achieve safely a microsurgical clipping of an intracranial aneurysm of the anterior circulation. Although many of these technical points discussed can apply to any kind of intracranial aneurysm, the very specific difficulties of the treatment of giant aneurysms or posterior circulation aneurysms were not mentioned. The usual pterional approach is described. The need of having a slack brain to perform easily the dissection of the aneurysm is stressed. Standards of hemodynamic control during surgery are described either with the use of a total or a proximal temporary clipping under the electrophysiologic control of the somesthetic evoked potential. Prevention of peroperative cerebral ischemia and brain protection are discussed. Dissection of the aneurysm is presented step by step until clipping. Different ways of clipping are discussed after a short description of the characteristics and composition of various available clips. How to deal with a premature intra-operative rupture of the aneurysm is also discussed. The last chapter describes step by step the approach and clipping of the four most frequent aneurysm locations i.e. at the posterior face of the intracranial internal carotid artery, the intracranial carotid bifurcation, the middle cerebral artery, and the anterior communicating artery.

Aneurysm, Ruptured↗
PubMed1993

Intraoperative facial nerve monitoring in posterior fossa acoustic neuroma surgery.

Intraoperative facial nerve monitoring has become an indispensable tool during cerebellopontine angle surgery. Ninety-seven patients underwent surgical removal of an acoustic neurinoma with the use of a pneumatic sensor monitoring between January 1, 1986, and December 31, 1990. In the early postoperative period, a normal or near-normal facial function (grades I and II) was achieved in 86% of the patients, a moderate dysfunction (grade III) was present in 7%, and a total or severe dysfunction (grades V or VI) was present in 6%. Normal function at 1 year was achieved in 90.5% of the patients, 4% were grade II, a moderate dysfunction (grade III) was present in 2%, and 3% showed a total or severe dysfunction (grade V and VI). The incidence of normal function decreased with tumor size, with an occurrence rate of 100%, 94%, and 91% in small, medium, and large tumors, respectively. In eight consecutive patients, all responses detected by the monitoring during the operation were collected and analyzed according to intraoperative events. Analysis of the results indicate that 95% of the 316 mechanically induced stimulations were of small or extremely small amplitude, and only 5% were of moderate amplitude. A medial-to-lateral strategy of dissection, preservation of the arachnoid veil over the facial nerve, a control by the monitoring of the amount of traction, and a more widespread use of sharp dissection were the major approaches to reduce surgical trauma during dissection.

Adult↗