French mobile neurosurgical unit: a retrospective analysis of 22 years of mission.

INTRODUCTION: The French mobile neurosurgical unit (MNSU) is used to provide specific support to remote military medicosurgical units deployed in foreign theatres. If a neurosurgical casualty is present, the Role 2 team may request the MNSU to be deployed directly from France. The deployed neurosurgeon can then perform surgery in Role 2 or decide to evacuate the casualty and perform surgery in Role 4 in France. We provide an epidemiological analysis of MNSU missions between 2001 and 2023 and investigate the value of the MNSU for the French Armed Forces. METHODS: We conducted a retrospective case series that included patients managed by the MNSU from 1 January 2001 to 31 January 2023. We collected epidemiological data (eg, age, military or civilian status, delay between transmission and takeoff, origin of the injury and mission location), clinical records (aetiologies of the injury and disease), data on surgical intervention (operator nature and type of surgery) and data on postoperative outcomes recorded at the time of discharge from hospital. RESULTS: 51 patients were managed by the MNSU. 36 (70.5%) and 3 (5.8%) patients underwent surgery on Role 2 and Role 4, respectively. 39 (76.9%) interventions were due to traumatic injury, 4 (7.8%) due to hydrocephalus, 4 (7.8%) due to vascular causes, 3 (5.9%) due to tumour and 1 (2%) due to spine degeneration. In 30 (76.9%) of these cases, the first operator was a neurosurgeon from the MNSU, whereas in the remaining 9 (23.1%) cases, procedures were initially performed by a non-neurosurgeon. CONCLUSION: The MNSU contribution to D1 casualties' strategic evacuation (STRATEVAC) is important. The MNSU provides additional support for STRATEVAC during the reorganisation of French Armed Forces engaged in several fronts. With the return of high-intensity wars, the French MNSU must develop and adjust for the management of massive influxes of casualties.

[Assessment of surgical teleconsultations in a developing country: two years of experience in Djibouti]. / Évaluation de la télé-expertise en chirurgie dans un pays en développement: une expérience de deux ans à Djibouti

OBJECTIVE: Our objective was to assess the influence of teleconsultations on patient management and clinical outcomes in a developing country. MATERIALS AND METHODS: All the surgical teleconsultations by a single surgeon (orthopedist) between November 2009 and November 2011 were recorded. RESULTS: Neurosurgery and pediatric orthopedics were the two most important specialities most often concerned, accounting for 67% of the 157 teleconsultations for 138 patients. The teleconsultations resolved the diagnostic uncertainties in 29 of 37 cases (78%). Advice from the expert modified management in 69% cases. Clinical outcomes were good or very good in 86% of the treated patients. CONCLUSIONS: This study establishes the feasibility and usefulness of surgical teleconsultations in Djibouti.

[Recurrent giant cystic vestibular schwannomas: role of cystoperitoneal shunt]. / Schwannomes vestibulaires kystiques géants: intérêt du drainage kystopéritonéal.

INTRODUCTION: Surgical removal of giant cystic vestibular schwannomas is difficult because of adherences between the cyst membrane, brainstem, and the VII-VIII nerve complex. The recurrence of the cyst is frequent and requires reoperation. The aim of this study was to analyze the role of the palliative cystoperitoneal shunt in giant cystic vestibular schwannomas. MATERIALS AND METHODS: Eighty-eight patients with a diagnosis of stage III or IV vestibular schwannoma were managed surgically from January 2000 to December 2005 in our department. Six schwannomas were deemed to be cystic according to the following criteria: a voluminous cystic component with mass effect causing symptoms as well as radiological and intraoperative identification of cystic elements. RESULTS: Complete tumor removal was achieved in two patients. After a follow-up of 5 and 7 years, these patients were asymptomatic. In four cases, we performed cyst drainage. For three patients, we implanted a permanent cystoperitoneal shunt. These patients were asymptomatic with a mean follow-up of 19.7 months. CONCLUSIONS: The cystoperitoneal shunt with no valve is a valid palliative surgical solution to remove brain stem compression. Neuronavigation allows proper positioning of the drain and secures the procedure.

Transfer of plasmid-mediated CTX-M-9 from Salmonella enterica serotype Virchow to Enterobacteriaceae in human flora-associated rats treated with cefixime.

Food animals are a potential source of CTX-M resistance genes for humans. We evaluated the transfer of the bla(CTX-M-9) gene from an animal strain of Salmonella enterica serotype Virchow to Enterobacteriaceae of the human intestinal flora by using human flora-associated (HFA) rats with and without cefixime treatment. In the absence of antibiotic, no transconjugant enterobacteria were found in the feces of HFA rats. However, the transfer rate was high if Escherichia coli J5 recipient strains were coinoculated orally with Salmonella. S. enterica serotype Virchow persisted in the rat fecal flora both during and after treatment with therapeutic doses of cefixime. The drug did not increase the transfer rate, and E. coli J5 transconjugants were eliminated from the flora before the end of cefixime treatment. No cefixime was recovered in the rat feces. In the presence of recipient strains, the bla(CTX-M-9) resistance gene was transferred from a strain of animal origin to the human intestinal flora, although transconjugant colonization was transient. Antibiotic use enhanced the persistence of donor strains, increasing the resistance gene pool and the risk of its spread.

[Study of the junction between the cortical bridging veins and basal cranial venous sinus]. / Etude anatomique du drainage des veines corticales inférieures dans le sinus transverse.

INTRODUCTION: The cerebral venous system is poorly known and is best appreciated based on macroscopic anatomical considerations. We present an anatomical and immunohistochemical study to better define the morphological characteristics of the junction between the inferior cortical veins and the transversal sinuses. MATERIAL AND METHODS: Sixteen cadaveric specimens from the anatomy laboratory of the University Victor-Segalen of Bordeaux were studied. The venous junctions with the transversal sinuses were observed under the operating microscope. Thirty vein-sinus junctions were immunohistochemically stained with smooth muscle actin. Ten venous junctions were observed under the electronic microscope. RESULTS: The inferior cortical veins drain into the transverse sinus either directly or through a tentorial sinus. The venous orifices in the transverse sinuses share the same characteristics. They are oval with semicircular superior dural reinforcement and follow an orientation opposite venous flow in the transversal sinus. The histologic study showed that the walls of the cortical veins contained smooth muscle cells as well as the dural reinforcement of the transversal sinuses. CONCLUSION: The venous orifices of the inferior cortical veins have the anatomical features of true sphincters. Their function in the regulation of the cerebral blood flow needs further exploration.

[Extradural spinal meningioma: case report]. / Méningiome rachidien extradural. A propos d'un cas et revue de la littérature.

OBJECTIVES: We report a case of purely extradural spinal meningioma and discuss the potential pitfalls in differential diagnosis. BACKGROUND: Spinal meningiomas account for 20-30% of all spinal neoplasms. Epidural meningiomas are infrequent intraspinal tumors that can be easily confused with malignant neoplasms or spinal schwannomas. CASE: A 62-year-old man with a previous history of malignant disease presented with back pain and weakness of the lower limbs. Magnetic resonance imaging revealed a well-enhanced T4 intraspinal lesion. The intraoperative histological examination showed a meningioma (confirmed by postoperative examination). Opening the dura mater confirmed the purely epidural location of the lesion. The postoperative course was uneventful with no recurrence 12 months after surgery. CONCLUSION: Purely extradural spinal meningiomas can mimic metastatic tumors or schwannomas. Intraoperative histology is mandatory for optimal surgical decision making.

[Neurological damage of brain tumor therapy]. / Complications neurologiques des traitements des tumeurs cérébrales.

Damage to the central nervous system induced by treatment of brain tumors is common and impairs the patient quality-of-life. Neurotoxicity is induced by synergistic effects of different cytotoxic treatments such as radiotherapy and chemotherapies administered concurrently or sequentially. Recent progress in the management of brain tumors has led to new neurotoxicities. The growing concern about the neuropsychological performance of patients has disclosed another type of brain damage which has been largely neglected to date. Neurological toxicity can be acute, requiring dose adaptation or a change of drugs. But it also often occurs late and can be irreversible. To date, treatments have been ineffective. The early diagnosis of neurotoxicity is thus a major challenge. Numerous clinical studies suggest an individual sensitivity which is not only related to age or vascular status, but also to genetic predisposition that remains to be detailed. Understanding the mechanisms of personal susceptibilities would be helpful in designing more tailored treatments. In this review we address the question of adverse effects of brain radiation as well as those of chemotherapy protocols which are particularly toxic for the central nervous system that is, methotrexate, platin and aracytin.

[Surgical management of synovial cyst of the lumbar spine: retrospective study of 52 patients]. / Prise en charge chirurgicale des kystes synoviaux lombaires: étude rétrospective concernant 52 patients.

PURPOSE OF THE STUDY: Lumbar synovial cysts are an uncommon cause of radiculopathy, low back pain and neurogenic claudication. We report a retrospective analysis of the clinical presentation, radiological studies, operative findings and outcome in 52 patients surgically treated for symptomatic lumbar synovial cysts. MATERIAL AND METHODS: Retrospective data from 52 consecutive patients treated from January 1996 to February 2006 were analyzed. We studied the clinical symptoms, diagnostic methods and radiological findings in all patients, reviewed the types of conservative therapy applied, the surgical findings and techniques, as well as the immediate and long-term results. Surgical outcomes were evaluated according to the Friedberg scale. RESULTS: There were 35 women and 17 men with an average age of 63.2 years (range 36-84 years). The most common symptoms were radiculopathy (65,4%) and neurogenic multiroot claudication (34,6%). Forty-seven patients had back pain and 22 paresthesia. Preoperative neurological examination demonstrated motor weakness (5.7%), sensory loss (7.6%). The radiological work-up consisted in CT-scan and/or MRI for all patients. The correct preoperative diagnosis was established in 44 patients. A total of 56 cysts were found. Five patients had bilateral cysts. The L4-L5 level was affected in 66%. Total resection of the synovial cyst was possible for 46 patients. No fusion was performed as a first line procedure. However, subsequent fusion was necessary in one patient who developed delayed symptomatic spondylolisthesis. Mean follow up period was 14 months ranging from six to 24 months. Three recurrences occurred during the follow-up period. Functional outcome was excellent in 61.6%, good in 34.6% and poor in 3.8%. CONCLUSION: Surgery should be proposed when synovial cysts fail to respond to conservative therapy. Recurrence and surgical complication rates are low. The usefulness of systematic fusion procedure is questionable.

Junction between the great cerebral vein and the straight sinus: an anatomical, immunohistochemical, and ultrastructural study on 25 human brain cadaveric dissections.

The cerebral venous system is poorly understood, and best appreciated under macroscopic anatomical considerations. We present an anatomical and immunohistochemical studies to better define the morphological characteristics of the junction between the great cerebral vein and the straight sinus. Twenty-five cadaveric specimens from the anatomy laboratory of the University Victor Segalen of Bordeaux were studied. The observation of the venous junctions with the straight sinus was performed under an operating microscope. The smooth muscular actin immunohistochemical staining was performed for 18 veno-sinosal junctions. Five venous junctions were observed using an electron microscope. We observed 3 different anatomic aspects: type 1 was a junction with a small elevation in its floor and a posterior thickening (14 cases); type 2 was a junction with an outgrowth on the floor like a cornice (7 cases); and type 3 was a junction presenting a nodule. Microscopic study of type 1 and 2 junctions showed a positive coloration to orceine attesting the presence of elastic fibers. Immunohistochemistry revealed the presence of smooth muscular actin and S 100 protein attesting the presence of smooth muscular fibers and nervous fibers. We observed in the ultrastructural study, a morphological progression of the endothelium. The venous orifice of the great cerebral vein into the straight sinus could be anatomically assimilated as a true "sphincter." Its function in the regulation of the cerebral blood flow needs further exploration.

Dynamics and genetics of PrPSc placental accumulation in sheep.

Placentae from scrapie-affected ewes are an important source of contamination. This study confirmed that scrapie-incubating ewes bearing susceptible genotypes could produce both abnormal prion protein (PrPSc)-positive and -negative placentae, depending only on the PRP genotype of the fetus. The results also provided evidence indicating that scrapie-incubating ARR/VRQ ewes may be unable to accumulate prions in the placenta, whatever the genotype of their progeny. Multinucleated trophoblast cells appeared to play a key role in placental PrPSc accumulation. PrPSc accumulation began in syncytiotrophoblasts before disseminating to uninucleated trophoblasts. As these result from trophoblast/uterine epithelial cell fusion, syncytiotrophoblast cells expressed maternal and fetal PrPC, whilst uninucleated trophoblast cells only expressed fetal PrPC. In ARR/VRQ scrapie-infected ewes, expression of the ARR allele by syncytiotrophoblasts appeared to prevent initiation of PrPSc placental deposition. The absence of prions in affected ARR/VRQ sheep placentae reinforces strongly the interest in ARR selection for scrapie control.

[Spinal cord compression by arachnoid cysts]. / Compression médullaire par kystes arachnoïdiens.

Spinal arachnoid cysts are considered to be rare entities, intradural locations are even less common. We report two cases of patients (two women aged 77- and 21-year-old) who presented spinal cord compression by intradural arachnoid cysts. For the second patient, repeated surgical procedures were necessary to improve the neurological status. After presenting the case reports, we expose the pathophysiological mechanisms and clinical features, and the surgical difficulties of treating this rare cause of spinal cord compression.

[Functional MR imaging and oligodendrogliomas]. / IRM fonctionnelle et oligodendrogliomes.

The localization of functional areas obtained from functional MRI (fMRI) is useful for patients suffering from tumors contiguous to eloquent brain areas. fRMI is an efficient tool in the strategy of treatment of low grade oligodendroglioamas in the rolandic area in intact or slightly impaired patients. It can be used preoperatively to assess motor functional areas. Indeed there is a good correlation for motor cortex lesions when using comparison between fMRI and intraoperative findings. Direct integration of fMRI data into neuronavigation enables to better visualize and preserve eloquent brain areas. One must be aware of fMRI limits. It is still often used with the control of direct cortical stimulations.

Determination of flumequine and 7-hydroxyflumequine in plasma of sheep by high-performance liquid chromatography.

A high-performance liquid chromatographic (HPLC) method for the simultaneous determination of flumequine and its metabolite 7-hydroxyflumequine in sheep plasma was described. The two compounds were extracted from 100 microl of plasma by liquid-liquid extraction. Aliquots (100 microl) were injected onto the HPLC system and separated on a LiChrospher Select B column with an isocratic system. The compounds were detected by fluorimetric detection for concentrations below 500 microg/l and by UV detection for the concentrations exceeding 500 microg/l. The range of the validated concentrations were 50000 to 5 microg/l and 500 to 10 microg/l with mean recovery rates of 87+/-3% and 60+/-1% for flumequine and 7-hydroxyflumequine, respectively.

Determination of residues of flumequine and 7-hydroxyflumequine in edible sheep tissues by liquid chromatography with fluorimetric and ultraviolet detection.

A simple, sensitive, and rapid method for simultaneous determination of residues of flumequine and its microbiologically active metabolite 7-hydroxyflumequine in 100 mg sheep edible tissues (muscle, liver, kidney, and fat) by liquid chromatography is reported. After liquid-liquid cleanup with ethyl acetate, tissue extracts were injected onto a Select B column. The 2 compounds were determined by ultraviolet and fluorimetric detection. The method was repeatable and reproducible for flumequine and 7-hydroxyflumequine in muscle, liver, kidney, and fat, with limits of detection below 2 and 3 micrograms/kg for flumequine and 7-hydroxyflumequine, respectively. Mean recoveries for flumequine were 90 +/- 7, 82 +/- 7, 89 +/- 5, and 82 +/- 6% in muscle, liver, kidney, and fat respectively. Mean recoveries for 7-hydroxyflumequine were 91 +/- 2, 90 +/- 4, 86 +/- 3, and 84 +/- 4% in muscle, liver, kidney, and fat, respectively.

Pharmacokinetics of flumequine in sheep after intravenous and intramuscular administration: bioavailability and tissue residue studies.

The pharmacokinetic properties of flumequine and its metabolite 7-hydroxyflumequine were determined in six healthy sheep after single intramuscular (i.m.) and intravenous (i.v) injections at a dose of 6 mg/kg body weight. The tissue residues were determined in 20 healthy sheep after repeated i.m. administration with a first dose of 12 mg/kg and nine doses of 6 mg/kg. The flumequine formulation used was Flumiquil 3% Suspension Injectable. The mean plasma concentrations of flumequine after i.v. administration were described by a three-compartment open model with a rapid distribution and a relatively slow elimination phase. The low value of volume of distribution at steady state (Vdss) (0.52 +/- 0.24 L/kg) and high value of volume of distribution (Vdlambda3) (5.05 +/- 3.47 L/kg) emphasized the existence of a small compartment with a slow rate of return to the central compartment. The mean elimination half-life was 11.5 h. The 7-hydroxyflumequine plasma levels represented 2.3% of the total area under the curve. The mean plasma concentrations of flumequine after i.m. administration were characteristic of a two-compartment model with a first order absorption. The mean maximal plasma concentration (1.83 +/- 1.15 microg/mL) was obtained rapidly, i.e. 1.39 +/- 0.71 h after the i.m. administration. The fraction of dose absorbed from the injection site was 85.00 +/- 30.13%. The minimal concentrations of flumequine during repeated treatment were significantly lower in females than in males. Eighteen hours after the last repeated i.m. administration, the highest concentration of flumequine was observed at the injection sites followed by kidney, liver, muscle and fat. The highest concentration of 7-hydroxyflumequine was observed in the kidney and was ten times lower than the flumequine concentration. The longest flumequine elimination half-life was observed in the fat.

Pharmacokinetic-pharmacodynamic model for spiramycin in staphylococcal mastitis.

Simultaneous pharmacokinetic-pharmacodynamic (PK/PD) modelling for spiramycin in staphylococcal infections of the mammary gland of cows was used to predict the efficacy of spiramycin. A differential equation derived from the Zhi model was fitted to an in vitro killing curve and post-antibiotic effect determination. A seven-compartment PK model, in which 4 compartments representing each quarter of the mammary gland which was considered to be the effect compartment, was included. The PD model linked to the PK model was able to describe the in vivo spiramycin effect against Staphylococcus aureus. The parameters calculated from in vitro data predicted a rapid decrease for the first 12-24 h, and regrowth within 72 h following the treatment, whereas in vivo the bacterial effect was much less after 24 h than that predicted by the in vitro data. PK/PD modelling permitted the simulation of various doses to optimize the efficacy of the antibiotic, taking into account such dynamic parameters as bacterial growth rate constant, bacterial killing rate constant and the Michaelis-Menten type saturation constant. An optimal dosage regimen of 20000 IU/kg per day for 3 days was predicted for the treatment of Staphylococcus aureus mastitis.

Determination of spiramycin and neospiramycin in plasma and milk of lactating cows by reversed-phase high-performance liquid chromatography.

After chloroform extraction, the rapid and sensitive determination of spiramycin and neospiramycin can be performed with AASP-diol clean-up cartridges prior to reversed-phase C18 high-performance liquid chromatography. The limits of quantification of spiramycin in plasma and milk are 0.023 and 0.013 microgram/ml, respectively, and those of neospiramycin, are 0.058 and 0.006 microgram/ml, respectively. Application of the method to the analysis of plasma and milk samples obtained from pharmacokinetic studies is described. Spiramycin has a terminal half-life of 14.27 h in plasma and 34.59 h in milk, while neospiramycin has a half-life of 25.62 h in plasma and 105.85 h in milk.