Biomedical subjects

M Lonjon

Publications and source records attributed to M Lonjon.

29 records · Page 2Linked to original sources

PubMed1998

Intramedullary spinal cord ependymomas in children: treatment, results and follow-up.

A retrospective review of 20 pediatric patients with intramedullary spinal cord ependymomas, all of whom underwent operative resection between 1985 and 1996, was undertaken to determine surgical results, long-term follow-up and tumor recurrence. Twelve children operated on in the same period with filum or cauda equina ependymomas were not included in this study. Nine children had had previous treatment before referral. Gross total resection was achieved in 14 patients and subtotal in 6. None of these had a post-operative radiation therapy. The median follow-up period was 67 months (range 25-177 months). All children were clinically evaluated before and after operation and at the last follow-up. The clinical grade at the last follow-up showed improvement in 8 patients (40%), was unchanged in 10 (50%) and deteriorated in 2 (10%). Three patients had a recurrence, 2 at the primary site (2 and 3 years after our surgery) and 1 at a distant site (3 years after). The actuarial 5- and 10-year survival rates were both 90%; 5- and 10-year progression-free survival rates were 93 and 70%, respectively. We conclude that a complete removal can be achieved in almost all cases of intramedullary spinal cord ependymomas in children, and that the long survival rates justify avoiding post-operative radiation therapy.

Adolescent↗

PubMed1998

Chiari Type I malformation and syringomyelia in unrelated patients with blepharophimosis. Report of two cases.

Syringomyelia is a rare, mainly sporadic disease of the spinal cord, which is associated with 80% of cases in which a Chiari Type I malformation is also present. A mendelian transmission of syringomyelia (autosomal dominant or recessive) has been proposed in approximately 2% of reported cases. The association of syringomyelia with hereditary diseases (Noonan's syndrome, phacomatoses) has been mentioned frequently in the literature. The authors report the presence of a Chiari Type I malformation accompanied by syringomyelia in two unrelated patients affected by a familial Type II blepharophimosis-ptosis-epicanthus inversus syndrome (BPES). The first patient was a 35-year-old woman who presented with a right C-8 root paresia. The second case involved a 20-year-old man who complained of cervical radicular pain. Both belong to families in which BPES was segregated in an autosomal dominant modality, but other family members had no known neurological symptoms. To the authors' knowledge, such a combination has never been described. Perhaps the possible involvement of a genetic component in some cases of Chiari Type I-associated syringomyelia will someday be debated.

Adult↗

PubMed1998

[Extracranial trigeminal schwannomas with middle temporal fossa development].

Schwannomas of trigeminal nerve account for 0.07% to 0.36% of all intra-cranial tumors. We report three observations about Jefferson's type D tumors, mainly extra-cranial with only small intra-cranial extension, concerning two men and one woman, who were respectively 36, 60 and 63 years old. Two of them presented with facial pain and hypoesthesia in the same territory. The third one developed a diplopia. In all cases, CT scanner analysis evidenced a large hypodense tumor extending in the infratemporal fossa. Temporal lobe and cavernous sinus were pushed aside by the intra-cranial extension. Tumors were hypo intense in T1-weighted image with significant enhancement after gadolinium injection. One of the tumors was a cystic form and in that case, an hyper signal in T2-weighted image was detected in the middle of the lesion. A combined subtemporal and transmaxillary approach was performed in 2 cases. In the third case, the removal of the tumor was only performed by a transmaxillary approach. In this series, there was no surgical mortality. One patient presented a postoperative residual painful anesthesia. In conclusion, extra-cranial schwannomas with intra-cranial extension are specially rare lesions. The most common early symptoms are facial neuralgia, facial hypoesthesia or diplopia. Neuroradiologic investigations, including CT and MRI evidence the precise anatomic site of the lesions. With the help of these techniques, total surgical tumor removal is possible in the majority of cases.

Adolescent↗

PubMed1998

[Use of the CCD (Sofamor-Danek) rod plates for instabilities of the craniospinal junction].

We report our experience with the CCD material (Sofamor-Danek) for the treatment of cranio-cervical instability. In this method, rod-plates are fixed to the occipital bone and to the cervical spine with hooks. This technique is mainly indicated for the treatment of patients with severe osteoporosis or with significant thinness of the occipital bone. Four cases are presented. Three of them suffered from a inflammatory rheumatism. The fourth patient had been previously treated by an occipito-cervical fixation with a Roy-Camille plate for a C2 metastasis and presented a failure of the occipital screws fixation. In all cases, no post operative complications were observed and all patients had a significant improvement of their cervicalgia. We confirm the interest and the fiability of the CCD method which has simplified the procedure and is specially suitable for the treatment of all types of cranio-cervical instability, even in the most adverse conditions.

Aged↗

PubMed1996

Boron neutron capture irradiation: setting up a clinical programme in Nice.

Neutron capture irradiation aims to selectively destroy tumor cells using 10B(n,alpha)7Li nuclear reactions produced within themselves. Following the capture reaction, an alpha particle and a, 7Li ion are emitted. Carrying an energy of 2.79 MeV, they destroy all molecular structures along their path close to 10 microns. These captures, used exclusively with a 'slow' neutron irradiation, provide a neutron capture therapy (BNCT). If they are used in addition to a fast neutron beam irradiation, they provide a neutron capture potentiation (NCP). The Centre Antoine-Lacassagne in Nice is actively involved in the European Demonstration Project for BNCT of grade IV glioblastomas (GBM) after surgical excision and BSH administration. Taking into account the preliminary results obtained in Japan, work on an 'epithermal' neutron target compatible with various cyclotron beams is in progress to facilitate further developments of this technique. For NCP, thermalized neutron yield has been measured in phantoms irradiated in the fast neutron beam of the biomedical cyclotron in Nice. A thermal peak appears after 5 cm depth in the tissues, delayed after the fast neutron peak at 1.8 cm depth. Thus, a physical overdosage of 10% may be obtained if 100 ppm of 10B are assumed in the tissues. Our results using CAL 58 GBM cell line demonstrate a dose modification factor (DMF) of 1.19 when 100 ppm of boric acid are added to the growth medium. Thus for the particles, issued from neutron capture, a biological efficiency at least twice that of fast neutrons can be derived. These results, compared with historical data on fast neutron irradiation of glioblastoma, suggest that a therapeutic window may be obtained for GBM.

Boron Neutron Capture Therapy↗

PubMed1995

Chromosomes in gliomatosis cerebri.

Gliomatosis cerebri is a rare brain tumor which histologically resembles a diffuse cerebral astrocytoma. It can simultaneously infiltrate multiple sites in the cerebrum, cerebellum, brainstem, and spinal cord. This remarkable diffuseness has led to the idea that gliomatosis cerebri does not derive from a solitary focus but must arise from a broad field of glial cells. We studied the chromosomes from gliomatosis cerebri in a 12-year-old boy by conventional cytogenetics and fluorescence in situ hybridization (FISH). Aside from normal cells, we found a majority of cells with the karyotype 44,XY,del(6)(q25),del(14)(q21), der(15;21)(q10;q10),add(18)(q22),del(19)(p12),add(20)(p13),-21. A smaller proportion of cells had 88 chromosomes with a doubling of this abnormal karyotype. These findings are consistent with a clonal neoplasm stemming from a single cell. The chromosome changes we observed, with the possible exception of the chromosome 6 deletion, did not resemble those frequently found in astrocytomas. Gliomatosis cerebri may therefore belong to a separate category of brain tumors.

Brain Neoplasms↗

PubMed1994

[Single cerebral metastasis of bronchopulmonary cancers].

The most frequent brain metastasis originates from a lung cancer. About half of them are unique. We report a series of 36 patients with lung cancer, operated for a single brain lesion. The mean age was 57.6 years, most (83.3%) were male. Most of the metastases originated from a primary adenocarcinoma (52.8%), in 10 patients (27.8%) from an epidermoid carcinoma, in 4 patients (11.1%) from a small cell carcinoma and in 3 patients from a mixed lesion. The metastatic lesion was detected before the primary lesion in 20 cases (55.5%). The mean post-operative survival was 9.6 months. 36% were alive one year after surgical treatment. We evaluated our clinical findings, histopathological studies and the type of surgical and medical post-operative management, at the cerebral and pulmonary level, in order to make a possible prognosis. In our series we found that only post-operative clinical status (Karnofsky score) and the post-operative neurological grading (Order classification) were significant factors (p < 0.001) to determine survival time.

Adenocarcinoma, Bronchiolo-Alveolar↗

PubMed1993

[Intracranial cavernoma. 30 cases].

During the last few years, as a result of improved neurodiagnostic procedure there has been an increase in the number of intracranial cavernous angioma. We present 30 cases totalling 32 cavernous angiomas. Twenty-one received a successful surgical treatment. Twenty-four angiomas were supratentorial (75 percent) and 8 subtentorial (25 percent). Cavernous angiomas are congenital vascular malformations, usually of small size, with multiple vascular cavities surrounded by fibrous walls. They are often found in young adults (mean age 35 years in our series), most frequently located in the supratentorial white matter. The presenting symptoms were epilepsy, haemorrhage and an expanding mass syndrome. In this series, 16 patients had epilepsy (53 percent), 7 had haemorrhage (23.5 percent) and 7 had a mass syndrome (23.5 percent). The diagnosis of this lesion, usually obtained with angiography, has been dramatically improved by CT scan and, particularly, MRI. The natural history of cavernous angiomas is still poorly understood: the major complication is haemorrhage. Total surgical excision is the treatment of choice: it avoids a possible haemorrhage and is effective in relieving epileptic seizures. The indication for surgery depends on the clinical symptom and the location of the lesion. The post-operative morbidity in our 21 operated cases was fairly low due to minor sequelae. In only 2 of the 16 patients who had epilepsy the clinical seizures persisted after surgery, but they were less frequent. The literature is reviewed.

Adolescent↗

PubMed1993

[Primary lymphoma of the cranial vault. Apropos of a case].

Primary lymphomas of the cranial vault are most unusual lesions. Only six cases have been described in the literature. We report a case of a 71 year old female who was admitted with an occipital mass. A C.T. scan revealed a mainly extra cranial tumor with an osteolysis of the cranial vault and a small intracranial component. It was diagnosed as a phenotype B centroblastic lymphoma. Half of the patients reported in the literature had a subcutaneous mass as the main symptom. These neoplasms are usually highly malignant tumors. The treatment realized is neurosurgical excision followed by chemotherapy and radiotherapy.

Aged↗

PubMed1992

[Intracranial dural arteriovenous fistula with spinal venous drainage].

Two cases of intracranial dural arteriovenous fistulae draining into the medullary veins are reported. One patient was a 68-year old man who experienced brief and repeated episodes of paraplegia, followed by a permanent spinal cord syndrome. The other patient was a 74-year-old woman who rapidly developed a syndrome of the medulla and spinal cord. In both cases spinal cord angiography failed to show vascular malformations, but myelography revealed venous imprints and magnetic resonance imaging of the cervical spinal cord disclosed a pre-medullary signal. Cerebral angiography showed an intracranial arteriovenous fistula fed by the external carotid artery and draining into the veins of the posterior fossa and the spinal venous network. Complete occlusion of the fistula was achieved by embolization with microparticles. Intracranial dural arteriovenous fistulae draining into the medullary veins are rare: to our knowledge, only 4 cases have been reported. Such lesions must be considered whenever a spinal cord syndrome has no detectable cause.

Aged↗

PubMedDate not supplied

Stroke after chiropractic manipulation as a result of extracranial postero-inferior cerebellar artery dissection.

OBJECTIVE: To describe a case of dissection of the postero-inferior cerebellar artery (PICA) after cervical manipulation. CLINICAL FEATURES: After cervical manipulation, a 42-year-old woman had a cerebellar syndrome related to an infarct in the area supplied by the PICA, confirmed by computed tomography of the brain. Cerebral angiography showed a normal appearance of the vertebral artery, a cervical extradural origin of PICA, and a dissection of the latter at the C1-C2 level. INTERVENTION AND OUTCOME: Anticoagulant treatment with heparin was implemented. A positive outcome was achieved after 3 weeks. CONCLUSION: Anatomical variations of the vertebral arteries and their branches are not infrequent and may constitute a predisposing factor to complications after neck manipulation.

Adult↗