PubMed Health⌕ Search

Biomedical subjects

M Zerah

Publications and source records attributed to M Zerah.

At least 19 recordsLinked to original sources

Treatment of high risk medulloblastomas in children above the age of 3 years: a SFOP study.

AIM: Improvement of EFS of children older than 3 years with high risk medulloblastoma. METHODS: Between 1993 and 1999, 115 patients (3-18 years, mean 8 years) with high risk medulloblastoma were included. After surgery treatment consisted of chemotherapy ('8in1' and etoposide/carboplatin) before and after craniospinal radiotherapy. RESULTS: Patients were staged using Chang-criteria (PF residue only, M1 and M2/M3) by local investigator as well as by central review panel (82.4% concordance). Chemotherapy was well tolerated without major delays in radiotherapy. With a mean follow up of 81 months (9-119), 5-year EFS was 49.8% and OS 60.1%. In detail according to subgroups EFS was 68.8% for PF residue only, 58.8% for M1 disease and 43.1% for M2/M3. CONCLUSION: M1 patients are legitimate high risk patients. Survival rates are still very low for high risk medulloblastoma patients and future trials should therefore focus on more intensive (chemotherapy/radiotherapy) treatment.

Adolescent↗

Finite element analysis of the strain distribution in the humeral head tubercles during abduction: comparison of young and osteoporotic bone.

AIM: The aim of this work was to design an accurate 3D digital model of the humerus and rotator cuff muscles. This model was then used to study strain distribution in humeral tubercles according to bone density. MATERIALS AND METHODS: The geometry of bone and muscle structures was reproduced using SURFDRIVER software, based on anatomical sections, CT scans and MRI images from the Visible Human Project image library. The contours were transferred to PATRAN software to rebuild volumes and mesh them. Calculations of strains and their distribution were performed using NASTRAN software. All the elements were considered to be isotropes. RESULTS: The study of the distribution of stress magnitude according to the type of bone modeled, shows that some stresses in cortical bone are greater than those in cancellous bone and are also greater in old bone, implying more deformation in old bone at constant force. This study also shows that stresses do not penetrate deeply into cancellous tissue. CONCLUSION: Observing the simulation results led understanding of the pathology of certain fractures of the proximal end of the humerus. This study also helped explain why certain types of osteosynthesis fail due to tubercles reconstruction failures.

Bone Density↗

Social and psycho-intellectual outcome following radical removal of craniopharyngiomas in childhood. A prospective series.

BACKGROUND: A prospective study on childhood craniopharyngiomas (CPs) was conducted from 1994 to 1998 to appreciate the pre- and postoperative clinical, endocrine, mental, and intellectual status of the patients and to determine the incidence and severity of the postoperative hypothalamic syndrome. METHODS: The series included 14 consecutive CPs. Twelve were retrochiasmatic and intraventricular, and two were partly prechiasmatic and extraventricular. All were treated with the aim of "total" removal. The removal was "total" in nine cases but incomplete in the other five. Immediate postoperative follow-up was uncomplicated in all cases. CONCLUSION: At 2-year follow-up, the two children with an extraventricular CP and a "total" tumor removal were intellectually normal, had no hypothalamic syndrome, and attended normal school with good results. The 12 others, although still intellectually normal, were more or less severely affected by a hypothalamic syndrome which altered their social insertion and caused academic failure. The authors conclude from this study that radical surgery should be reserved to extraventricular CPs only.

Adolescent↗

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↗

[Neurofibromatosis 1: recommendations for management].

Twenty experts, members of a French medical network devoted to neurofibromatosis 1 have elaborated recommendations for the management of the disease. Bibliography was obtained through a Medline of articles from 1966 to 1999 for the terms neurofibromatosis, NF1, neurofibroma and from textbooks. A consensual document was written taking into account extracted data. An annual careful clinical examination is recommended except in cases with complications. Screening investigations are not recommended due to the rarity of complications, generally symptomatic and easily detected during the clinical follow-up. The only controversial exception might be magnetic resonance imaging for early detection of optic pathway gliomas in young children. A co-ordinated follow-up in specialised multidisciplinary centres, providing patients with a rational management, is recommended.

Adolescent↗

Growth hormone deficiency: permanence and diagnosis in young adults.

OBJECTIVE: To optimize the tools for diagnosing idiopathic growth hormone (GH) deficiency. METHODS: We compared the data of 43 young adults treated for GH deficiency before and after GH treatment and puberty. Those with organic lesions were assigned to group 1 (n = 9), those with certain GH deficiency (n = 11) to group 2 and those with no criterion of certitude of GH deficiency to group 3 (n = 23). RESULTS: Group 1 patients: the GH peaks at first [1.5 +/- (SE) 0.4 microg/l] and second (1.9 +/- 0.7 microg/l) evaluations before treatment were similar to those at the third evaluation (1.2 +/- 0.8 microg/l) after treatment. Group 2 patients: they had similar peaks (2.6 +/- 0.8, 2.9 +/- 0.5 and 5.5 +/- 1.4 microg/l). Group 3 patients: the peaks increased from 4.9 +/- 0.4 and 4.8 +/- 0.4 to 18.4 +/- 2.3 microg/l (p < 0.0001); 87% had a GH peak >10 microg/l at this evaluation. The plasma insulin-like growth factor 1 was initially below -2 z-score in 12/13 of these patients and similarly low in 4/17 patients at the third evaluation. The growth rates of the three groups before and their increase during the 1st year of treatment were similar. CONCLUSION: Almost all patients with GH deficiency before puberty without criteria of certitude had a normal GH peak after puberty. Some of these patients probably had a transiently low GH secretion.

Adolescent↗

[Treatment of intracranial cysts in children: peritoneal derivation or endoscopic fenestration?].

OBJECTIVE: The goal of this study is to evaluate the indications, benefit and complications of shunts and endoscopic fenestrations in the treatment of malformative intracranial cysts. MATERIAL AND METHOD: The records of 172 consecutive children (mean age of 4 years) were reviewed. All had a malformative cyst. Dandy Walker malformation, mega cisterna magna, and cysts from tumoral or porencephalic origin were excluded from the study. The cysts were diagnosed either in utero (n=64) or postnatally (n=108). Most of them were unique (94.8%) and localized in the posterior fossa (26.2%) or at the convexity (23.2%). Indication for surgery was based on clinical symptoms (n=101; 86.3%) or size of the lesion (n=16; 13.7%). Endoscopy was the treatment of choice when cysts were in closed relationship with enlarged ventricles. Shunting procedures were indicated when endoscopy was not feasible and craniotomies when shunt insertion was unsafe or diagnosis uncertain. Fifty children underwent an endoscopic fenestration, 55 a shunting procedure, 7 the puncture or the external drainage of a pericerebral collection and 5 a direct surgical approach. The mean follow-up was 5.5 years. Psycho-motor, intellectual and school performances were evaluated in 93 children (54%). Success was defined by both the disappearance of symptoms of increased intra cranial pressure and regression of the cyst. RESULTS: Compared to shunts, endoscopic fenestrations were more frequently successful (70% vs 61.8%), led to less complications (6% vs 61.8%) and to a lesser number of reoperations (in average 1.6 operation per child vs 2.2). Median developmental and intellectual quotients for the whole series were respectively 98 and 97 and did not depend upon the type of treatment. CONCLUSION: The study of this series shows that treatment modalities necessarily vary according to the site of the cysts but that endoscopic fenestrations are preferable to shunts whenever feasible.

Brain Diseases↗

Respiratory obstruction as a sign of brainstem dysfunction in infants with Chiari malformations.

Laryngeal respiratory obstruction associated with Chiari malformations was first described in 1932. We studied this type of obstruction in six children with one or several disorders pointing to brainstem dysfunction (failure to thrive, velopharyngeal incompetence, gastroesophageal reflux, or vagal hypertonia). The nature of the laryngeal obstruction was highly variable (vocal cord paralysis, paradoxical vocal cord motion, laryngomalacia) as were the frequency and severity of associated disorders. Chiari malformations should be routinely sought in a child with laryngeal respiratory obstruction occurring at birth or later, whatever the endoscopic diagnosis, especially when signs of brainstem dysfunction are present. The best tool for diagnosing the Chiari malformation is T1- and T2-weighted MRI. Signs of brainstem dysfunction must be treated symptomatically, before treating Chiari malformations by decompressive surgery. This latter approach led to full functional recovery in all five children who underwent the procedure. Palliative surgical treatment should be reserved for patients in whom this procedure is unsuccessful.

Airway Obstruction↗

Is the sitting or the prone position best for surgery for posterior fossa tumours in children?

BACKGROUND: The aim of this study was to compare complications in children operated for posterior fossa tumours in the sitting position with those in the prone position. METHODS: We retrospectively assessed the perioperative course of posterior fossa tumour (PFT) surgery according to the operating position. Sixty children were operated in the sitting position (SP) and 19 in the prone position (PP). Preoperative data were not different between groups. RESULTS: Patients in the PP group received a larger median (95% confidence interval) volume of intraoperative blood transfusion than patients in the SP group [200 (20-325) versus 0 (0-80) ml, P=0.04]. Intraoperative complications, as well as severe perioperative complications were more frequent in the PP group (P=0.01). The median duration of tracheal intubation [20 (18-24) versus 36 (18-72) h, P=0.037], of ICU stay [2 (2-3) versus 4 (2-5) days, P=0.02] and of hospital stay [11 (9-12) versus 14 (10-20) days, P=0.02] was longer in the PP group compared with the SP group. CONCLUSIONS: PFT surgery in the sitting position in children is not associated with an increased number or severity of perioperative complications, while the postoperative course appears better in this position.

Astrocytoma↗

Management of hydrocephalus in pediatric patients with posterior fossa tumors: the role of endoscopic third ventriculostomy.

OBJECT: The authors undertook a study to evaluate the effectiveness of endoscopic third ventriculostomy in the management of hydrocephalus before and after surgical intervention for posterior fossa tumors in children. METHODS: Between October 1, 1993, and December 31, 1997, a total of 206 consecutive children with posterior fossa tumors underwent surgery at Hĵpital Necker-Enfants Malades in Paris. Excluded were 10 patients in whom shunts had been placed at the referring hospital. The medical records and neuroimaging studies of the remaining 196 patients were reviewed and categorized into three groups: Group A, 67 patients with hydrocephalus present on admission in whom endoscopic third ventriculostomy was performed prior to tumor removal; Group B, 82 patients with hydrocephalus who did not undergo preliminary third ventriculostomy but instead received conventional treatment; and Group C, 47 patients in whom no ventricular dilation was present on admission. There were no significant differences between patients in Group A or B with respect to the following variables: age at presentation, evidence of metastatic disease, extent of tumor resection, or follow-up duration. In patients in Group A, however, more severe hydrocephalus was demonstrated (p < 0.01): the patients in Group C were in this respect different from those in the other two groups. Ultimately, there were only four patients (6%) in Group A compared with 22 patients (26.8%) in Group B (p = 0.001) in whom progressive hydrocephalus required treatment following removal of the posterior fossa tumor. Sixteen patients (20%) in Group B underwent insertion of a ventriculoperitoneal shunt, which is similar to the incidence reported in the literature and significantly different from that demonstrated in Group A (p < 0.016). The other six patients (7.3%) were treated by endoscopic third ventriculostomy after tumor resection. In Group C, two patients (4.3%) with postoperative hydrocephalus underwent endoscopic third ventriculostomy. In three patients who required placement of CSF shunts several episodes of shunt malfunction occurred that were ultimately managed by endoscopic third ventriculostomy and definitive removal of the shunt. There were no deaths; however, there were four cases of transient morbidity associated with third ventriculostomy. CONCLUSIONS: Third ventriculostomy is feasible even in the presence of posterior fossa tumors (including brainstem tumors). When performed prior to posterior fossa surgery, it significantly reduces the incidence of postoperative hydrocephalus. The procedure provides a valid alternative to placement of a permanent shunt in cases in which hydrocephalus develops following posterior fossa surgery, and it may negate the need for the shunt in cases in which the shunt malfunctions. Furthermore, in patients in whom CSF has caused spread of the tumor at presentation, third ventriculostomy allows chemotherapy to be undertaken prior to tumor excision by controlling hydrocephalus. Although the authors acknowledge that the routine application of third ventriculostomy in selected patients results in a proportion of patients undergoing an "unnecessary" procedure, they believe that because patients' postoperative courses are less complicated and because the incidence of morbidity is low and the success rate is high in those patients with severe hydrocephalus that further investigation of this protocol is warranted.

Adolescent↗

[Benign childhood intracranial hypertension].

INTRODUCTION: Infrequent in children, benign intracranial hypertension (or pseudotumor cerebri) is most often observed in adults. Careful diagnosis requires eliminating all the other etiologies of intracranial hypertension. Most often medical, its treatment must be rapid to avoid permanent visual loss. However, a surgical procedure is necessary when vision is threatened. We present our experience with this pathology and discuss its clinical aspects, its etiologies, and the physiopathological mechanisms. PATIENTS AND METHODS: We conducted a retrospective study on children who presented benign intracranial hypertension confirmed by neuroradiological and neurosurgical examinations. These examinations also served to specify the responsible etiologies. The ophthalmologic examinations, adapted to the child's age and clinical status, included visual acuity testing, optic disc evaluation, ocular motility testing, and visual field evaluation. Progression of visual acuity and the topic disc was analyzed after treatment. RESULTS: The diagnosis of benign intracranial hypertension was confirmed in 22 children (12 boys and 10 girls). Clinical presentation included headache and visual disturbance such as visual loss and oculomotor nerve palsy. Papilledema was present in nearly all cases. Medical treatment was successful in 7 children; however, the remaining 15 patients required a lumboperitoneal shunt because of elevated intracranial pressure, no response to the medical therapy, or threatened vision. DISCUSSION: The physiopathological mechanisms of benign intracranial hypertension, an uncommon condition in children, are still unclear. It can be associated with severe visual loss. All other intracranial or medullary expansive lesions should be eliminated before diagnosis. The causes of this syndrome are not the same for pediatric and adult patients. Although medical therapy is usually sufficient to normalize the intracranial pressure, a lumboperitoneal shunt is at times required. The role of the ophthalmologist is important in detecting a possible visual loss or papilla abnormality and in ensuring proper treatment follow-up. CONCLUSION: Ophtalmologists are involved in the detection of pseudotumor cerebri and the monitoring of visual function, an important element in evaluating treatment efficacy.

Adolescent↗

Emergency management of deeply comatose children with acute rupture of cerebral arteriovenous malformations.

PURPOSE: To assess the impact of emergency management on mortality and morbidity of acute rupture of cerebral arteriovenous malformations resulting in deep coma in children, and the factors predicting outcome. METHODS: Retrospective chart review of 20 children with a Glasgow Coma Scale < or = 8 with acute hemorrhagic stroke from a cerebral arteriovenous malformation rupture was conducted. Protocol included: early resuscitation with tracheal intubation and ventilation after induction of anesthesia with sufentanil, and benzodiazepine, and mannitol 20% or hypertonic saline 7.5% infusion for life-threatening brain herniation. Radiological exploration was limited to contrast-enhanced CT scan preceding immediate surgical decompression. Postoperatively, children were deeply sedated and intracranial pressure monitoring allowed titration with osmotherapy, vasopressors, hyperventilation or barbiturate coma to control cerebral perfusion pressure. Analysis used stratification of the type of hemorrhage (supra or infra tentorial), location (intraparenchymal and subarachnoid, intraparenchymal and intraventricular or intraventricular alone) and relationship between presentation, evolution with resuscitation, type of cerebral lesion, and outcome. RESULTS: Patients had a severe initial presentation (median Glasgow Coma Scale five), eight had unilateral and eight bilateral third nerve palsy. Compressive hematoma in supratentorial localisation represented 75% of the cases. Global mortality was 40%. Persistence of mydriasis after resuscitation increased mortality to 75%. Massive intraventricular flooding was associated with increased mortality. Good functional outcome was achieved in survivors. CONCLUSION: Acute rupture of an AVM can result in rapidly progressing coma. Emergency management with early resuscitation, minimal radiological exploration before rapid surgical decompression results in a mortality rate of 40%, but a good functional outcome can be expected in the survivors.

Acute Disease↗

The management of desmoplastic neuroepithelial tumours in childhood.

The authors report on the clinicopathological aspects of and management strategies for the group of rare, large hemispheric childhood tumours recently classified as desmoplastic infantile ganglioglioma (DIGG), desmoplastic astrocytoma of infancy (DACI) and pleomorphic xanthoastrocytoma (PXA). Between 1985 and 1997, ten children (4 with DACIs, 4 with DIGGs and 2 with PXAs) with a median age of 9.5 months were operated on. All these patients had complete surgical resections, with two having a preoperative biopsy. This led to an erroneous diagnosis in both cases of malignant grade 4 astrocytoma. As a result, one patient had preoperative chemotherapy with no effect. There was one perioperative death. Histology revealed heterogeneous tumours with malignant looking areas in 8 of the specimens. None of the patients has had any postoperative adjuvant treatment. All surviving patients are alive at follow-up (median 4.2 years). Despite their often malignant appearance, these tumours have an excellent prognosis, but they can present formidable surgical challenges when they occur in very young age patients. We believe that surgical excision can offer a cure and that adjuvant treatment is not necessary. Finally, biopsy is of little value and may even lead to an erroneous diagnosis and subsequent mismanagement.

Astrocytoma↗