Histological and biomechanical study of dura mater applied to the technique of dura splitting decompression in Chiari type I malformation.

International audienceMany techniques are described to treat Chiari type I malformation. One of them is a splitting of the dura, removing its outer layer only to reduce the risks of cerebrospinal fluid (CSF) leak. We try to show the effectiveness of this technique from histological and biomechanical observations of dura mater. Study was performed on 25 posterior fossa dura mater specimens from fresh human cadavers. Dural composition and architecture was assessed on 47 transversal and sagittal sections. Uniaxial mechanical tests were performed on 22 dural samples (15 entire, 7 split) to focus on the dural macroscopic mechanical behavior comparing entire and split samples and also to understand deformation mechanisms. We finally created a model of volume expansion after splitting. Dura mater was composed of predominant collagen fibers with a few elastin fibers, cranio-caudally orientated. The classical description of two distinct layers remained inconstant. Biomechanical tests showed a significant difference between entire dura, which presents an elastic fragile behavior, with a small domain where deformation is reversible with stress, and split dura, which presents an elasto-plastic behavior with a large domain of permanent strain and a lower stress level. From these experimental results, the model showed a volume increase of approximately 50% below the split area. We demonstrated the capability of the split dura mater to enlarge for suitable stress conditions and we quantified it by biomechanical tests and experimental model. Thus, dural splitting decompression seems to have a real biomechanical substrate to envision the efficacy of this Chiari type I malformation surgical technique

Same Diagnosis but Different Story! A Tale of Two Primary Lymphomas of the Calvaria

We present 2 cases of isolated tumour of the calvaria that underwent a different management but, unexpectedly, the same very rare diagnosis of primary diffuse large B-cell lymphoma of the cranial vault. Unfortunately, the outcome was the opposite due to numerous factors. We discuss herein the radiological diagnosis and surgical options in the light of the literature

Diversité génétique de Toxoplasma gondii à partir de prélèvements paraffinés d'abcès cérébraux de 20 patients immunodéprimés : l'expérience de l'hôpital Lariboisière (Paris).

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Lipofilling: A New Therapeutic Option for the Treatment of Lupus Panniculitis-Induced Atrophy

Lupus panniculitis is a rare manifestation of cutaneous lupus erythematosus, which may lead to major aesthetic sequelae with a severe impact on patients’ quality of life. We report 2 cases supporting the short- and long-term efficacy and safety of lipofilling in the treatment of lupus panniculitis-induced atrophy. These observations pave the way for prospective, larger-scale studies in patients with scarring lupus panniculitis, provided that the autoimmune pathogenic process is in complete, stable remission

Serotonin-producing pancreatic endocrine tumour. Histological, ultrastructural and immunohistochemical study of a case

Serotonin-producing pancreatic endocrine tumours are rare neoplasms which in most cases exhibit malignant biological behaviour. These tumours, in the majority of the well-documented cases, are composed of argyrophil- and argentaffin-positive cells which contain large pleomorphic neurosecretory granules. In contrast, argyrophilic non-argentaffin pancreatic endocrine tumours with tumour cells containing round neurosecretory granules are exceptional. In this study we describe such a tumour not associated with clinical evidence of carcinoid syndrome in a 60-year-old woman. Histological examination revealed tumour extension in pancreatic lymphatic vessels and veins but no evidence of locoregional or distant metastases. Ten months after surgery the patient showed no recurrence of the disease. Immunohistochernistry revealed cytoplasmic serotonin production in the tumour cells which were negative for anti-gastrin, insulin, glucagon, somatostatin, pancreatic polypeptide (PP), vasoactive intestinal peptide (VIP) and ACTH. This study emphasizes the usefulness of combined ultrastructural and immunohistochemical investigations in order to identify and characterize the rare pancreatic endocrine tumours with serotonin production

Immunohistochemical detection of cell proliferation in gastric carcinomas with the monoclonal antibody ki-67. A study of 24 cases

The proliferative activity in 24 gastric carcinomas was determined by an immunohistochemical method using monoclonal antibody Ki-67 (ABC method). Immunostained nuclei were counted by two observers through a Nachet NS 1000 image numeriser. Three grades were defined according to stained nuclei percentage (proliferation index Pi = percentage of cells engaged in cellular cycle outside Go): grade 1 (Pi < 20%); grade 2 (20% 40%). About 60% of tumours were in grade 1 and 10% in grade 3. No correlations were observed between Pi and the following parameters: histological differentiation; parietal extension; presence or absence of metastasis. These results may be compared to the two other avalable studies of Ki-67 antibody in gastric cancers. Our study also showed a heterogeneous distribution of immunostained nuclei, within each single tumour and from one tumour to another, which has been noted in one previous study and in a similar one we made on colorectal carcinoma. This heterogeneity is the consequence of the variability of carcinomatous cell proliferative activity; an important biological factor in the evaluation of tumoral process. The proliferative activity in gastric carcinomas provides an estimation of tumour dynamics that might be a prospective criterium for tumoral process evaluation

Female gender and exogenous progesterone exposition as risk factors for spheno-orbital meningiomas

International audienceObjectiveThe great heterogeneity of meningiomas is challenging and we need to distinguish relevant subgroups. Spheno-orbital osteomeningiomas (SOOM) constitute a clinically specific entity, with slow-growing benign osteo-meningiomatous tumors, which recur after surgery in one fourth of cases. Neurosurgical daily practice, supported by the literature, shows that the vast majority of patients with SOOM are women, and we explored whether their epidemiological and hormonal profiles suggest a progesterone influence.MethodsWe retrospectively documented all radiologically and histologically confirmed cases of SOOM operated in 2005–2019 in our institution. We completed the clinical and hormone history by systematic telephone interviews.ResultsIn the literature, SOOM occur significantly more often in women than other meningiomas (749/847, 86.4% versus 73.8%, p = 0.002). Among 175 cases, we included 124 patients, 93.5% were women, younger than men (51 ± 5 versus 63 ± 8, p = 0.02). Women’ meningiomas showed more progesterone receptors (96.4% versus 50%, p < 0.001). Exogenous hormonal intake, reliable in 82 cases, concerned 83.3% (64/78) of women, with frequent progesterone intake: 13 oestroprogestogenic treatment only, with old-generation progesterone analogs, 41 progesterone analogs (cyproterone acetate, nomegestrol acetate, chlormadinone, promegestone, etonogestrel, levonogestrel), 7 substitutive hormonal therapy for menopause, 3 others. Duration of treatment was 2–40 years, median 10 years.ConclusionsSOOM develop preferentially in women in their fifties, who often received progesterone analogs, and show progesterone receptors. Progesterone analogs are incriminated in skull base meningiomas, and this is the first report on the prevalence of exogenous hormone therapy specifically in SOOM. Whether SOOM reduce after treatment discontinuation, in particular the osteoma part, needs to be explored. Anti-progesterone treatments may represent an avenue for future research in soom

Cerebral Amyloid Angiopathy Related Inflammation With Prominent Meningeal Involvement. A Report of 2 Cases

International audienceCerebral amyloid angiopathy related inflammation (CAA-RI) is a rare form of CAA characterized by subacute encephalitic symptoms (cognitive decline, seizures, focal deficits) associated with extensive and confluent white matter lesions co-localizing with lobar microbleeds on brain MRI. We report two cases of unusual CAA-RI mimicking meningoencephalitis but without typical brain lesions on FLAIR and T2* sequences. These 2 cases may extend the clinical spectrum of CAA-RI by suggesting the possible occurrence of quite purely meningeal forms of CAA-RI