Comparison of conventional ligatures and a vessel sealing device for haemostasis during open ovariohysterectomy in rabbits

AIMS

To compare surgical times and rates of intra-operative and post-operative complications for open ovariohysterectomy (OVH) in female rabbits using conventional ligatures or a vessel sealing device (VSD) for haemostasis.

METHODS

Female pet rabbits (n = 23) presented for OVH for either desexing or treatment of reproductive disorders were randomly assigned to a conventional ligatures (CL) group (n = 12) or a LigaSure 5-mm (LS5) group (n = 11). In the CL group, the ovarian pedicles were ligated with a single surgeon's knot. After transection of the ovarian pedicles, the broad ligament was manually broken down along the uterine horns to their respective cervices. In the LS5 group, both ovarian pedicles and the broad ligaments were sealed with a LigaSure Dolphin Tip VSD with 5-mm forceps. All the rabbits were hospitalised for 24 hours after surgery. Two weeks after discharge, a clinical recheck examination was performed. Incision length, overall surgical time (from initial incision to completion of intradermal suturing), OVH time (from identification of the first ovary to transection of the vaginal vault), and intra- and post-operative complications were recorded and compared between groups, using the Student's t-test for normally distributed continuous data, the Wilcoxon-Mann-Whitney test for non-normally distributed continuous data and Pearson's χ2 test for categorical data.

RESULTS

The mean overall surgical time was 14.1 (SD 4.4) minutes. The surgery took 15.0 (SD 4.9) minutes in the CL group and 13.1 (SD 3.8) minutes in the LS5 group (p=0.10). The OVH time was shorter in the LS5 group (mean 4.2 (SD 0.9) minutes) than in the CL group (mean 6.3 (SD 1.7) minutes; p = 0.005). No intra-operative complications were encountered in the LS5 group. Haemorrhage occurred in three rabbits in the CL group. One rabbit in the LS5 group developed steatonecrosis post-operatively. There was no evidence of a difference in the proportion of rabbits that experienced intra- and post-operative complications (p = 0.25 and p = 0.94 respectively) between groups.

CONCLUSIONS

The use of a LigaSure 5-mm VSD and conventional ligatures during open OVH were both associated with similar overall surgical times and complication rates. The OVH times were shorter in the LS5 group compared to the CL group.

CLINICAL RELEVANCE

Use of the LigaSure 5-mm VSD allows efficient haemostasis while performing open OVH in female pet rabbits.

Theoretical and experimental study of peroxy and alkoxy radicals in the NO3-initiated oxidation of isoprene

Under atmospheric conditions, nitrate-RO₂ radicals are equilibrated and react predominantly with HO₂, RO₂ and NO. The nitrate-RO chemistry is affected strongly by ring closure to epoxy radicals, impeding formation of MVK/MACR.

Microvascularization of the human central and peripheral nervous system: A new microcomputed tomography method

Microcomputed X-ray tomography (microCT), developed since the late 1990s, is a miniaturized version of the tomographs used daily in medical imaging. It produces vascular images that are different from those obtained by microradiography, in particular by facilitating the vision in space, thus understanding microvascularisation. The anatomical specimens, once treated with formalin, are injected with a mixture made of gelatin containing a contrast product (barium) and then analyzed by microCT. The acquisition times that can exceed 24hours and metal sheets used for X-ray filtering vary according to the sample. The projection images are reconstructed to produce 2D sections. These are combined for the reconstruction of 3D models using a volume rendering software. Four examples will allow the imaging of microvascularization: the inferior alveolar nerve, the cerebral cortex and pia-mother, brain stem, central gray nuclei (ganglia at the base of the brain). Small capillaries are highlighted using high-end software for reconstruction. Conventional software or freeware cause a considerable loss of information on small vessels that are not visualized. The VGStudio max high-end software allows the production of videos that are particularly useful for 3D exploration and teaching (four videos are provided with this article).

AMBUCOV : description d’un système de dépistage hospitalier en ambulatoire en réponse à l’épidémie de CoViD-19

Introduction

Suite à la déclaration d’épidémie de pneumopathies au nouveau coronavirus CoViD-19 en Chine en décembre 2019, 11 patients ont été confirmés infectés en France du 20/01 au 10/02/2020 dont 5 en Île-de-France. Devant l’afflux de personnes nécessitant un dépistage et le manque de place en unité d’isolement dans les établissements de soins référent (ESR), un système dégradé d’accueil pour le dépistage des cas suspects de CoViD-19 a été élaboré. En concertation avec les autorités sanitaires françaises et la direction de l’hôpital, le département des maladies infectieuses a développé le projet AmbuCoV pour pouvoir accueillir au mieux et sans délais toutes les personnes qui lui étaient adressées.

Matériels et méthodes

Mise en place d’une unité dédiée pour la prise en charge des personnes nécessitant un dépistage pour le CoViD-19 et ne justifiant pas d’une hospitalisation. L’unité AmbuCoV, ouverte 24 h/24 et 7j/7, a fonctionné avec le personnel minimum et respecté un parcours patient développé par l’équipe pluridisciplinaire du service pour le dépistage et l’isolement au sein de l’établissement. Le laboratoire de virologie procédait à deux séries de PCR par jour, avec un rendu des résultats vers 13 h pour les prélèvements envoyés avant 8 h, et 19 h pour ceux envoyés avant 14 h. Une évaluation interne a été menée afin d’évaluer quantitativement et qualitativement ce dispositif.

Résultats

AmbuCoV a été ouvert le 31 janvier 2020 et comprenait 22 lits répartis en 16 chambres. Une infirmière effectuait le prélèvement nasopharyngé et la prise des constantes dans le box dédié en pression négative de l’unite d’isolement. Les personnes sans ATCD et paucisymptomatiques (constantes normales, t < 38 °C, absence de dyspnée et de toux) étaient accompagnées pour être isolées dans l’unité AmbuCoV jusqu’à réception des résultats. Ces patients ne nécessitant pas de soins infirmiers, une aide-soignante présente dans l’unité en permanence répondait à leurs besoins et assurait le lien avec les infirmières et médecins du service. En cas d’infection CoViD-19 confirmée les patients devaient être hospitalisés dans l’unité d’isolement. Les deux premières semaines, 15 personnes de 10 à 48 ans ont été admises dans AmbuCov soit 20 % des personnes admises pour dépistage du CoViD-19 dans notre ESR. Nous présentons en photos et à l’aide de figures la procédure et le parcours des personnes prises en charge. Aucune personne suspecte d’infection à CoViD-19 ne s’est vue refusée l’admission pour dépistage dans notre ESR. Les usagers et le personnel soignant se sont montrés satisfaits de ce programme. La principale limitation à l’utilisation de l’unité AmbuCoV était l’absence de pression négative dans les chambres qui contre-indiquait la prise en charge des personnes présentant une toux ou des signes broncho-pulmonaires. Un système de recyclage de l’air par appareil mobile (Plasmair) est à l’essai.

Conclusion

Nous avons mis en place une stratégie de dépistage ambulatoire d’une infection virale émergente pour faire face à l’augmentation de patients et de cas suspects en contexte épidémique. Cette unité baptisée AmbuCoV nous a permis de faire face rapidement et efficacement à l’afflux de personnes et pourra être réutilisée à l’avenir en cas de nouvelle épidémie. Nous souhaitons partager notre expérience, ainsi que son évaluation en termes de points forts et difficultés rencontrées, afin qu’elle puisse servir à d’autres personnels de santé.

Acute intracranial hypertension management in metastatic brain tumor: A French national survey

BACKGROUND

Brain metastases occur in 15-30% of cancer patients and their frequency has increased over time. They can cause intracranial hypertension, even in the absence of hydrocephalus. Emergency surgical management of brain metastasis-related intracranial hypertension is not guided by specific recommendations.

OBJECTIVE

We aimed to make a French national survey of emergency management of intracranial hypertension without hydrocephalus in the context of cerebral metastasis.

METHODS

A national online survey of French neurosurgeons from 16 centers was conducted, consisting of three clinical files, with multiple-choice questions on diagnostic and therapeutic management in different emergency situations.

RESULTS

In young patients without any previously known primary cancer, acute intracranial hypertension due to a seemingly metastatic single brain tumor indicated emergency surgery for all those interviewed; 61% aimed at complete resection; brain MRI was mandatory for 74%. When a primary cancer was known, 74% of respondents were more likely to propose surgery if an oncologist confirmed the possibility of adjuvant treatment; 27% were more likely to operate on an emergency basis when resection was scheduled after multi-disciplinary discussion, prior to acute degradation.

CONCLUSION

Currently, there is no consensus on the emergency management of intracranial hypertension in metastatic brain tumor patients. In case of previously known primary cancer, a discussion with the oncology team seems necessary, even in emergency. Decision criteria emerge from our literature review, but require analysis in further studies.

Long term surgical results of 154 petroclival meningiomas: A retrospective multicenter study

BACKGROUND

Outcomes of petroclival meningiomas (PCM) (morbidity, permanent cranial nerves deficit, tumor removal and recurrence) are inconsistent in the literature, making it a challenge to predict surgical morbidity.

METHODS

A multicenter study of patients with PCMs larger than 2.5cm between 1984 and 2017 was conducted. The authors retrospectively reviewed the patients' medical records, imaging studies and pathology reports to analyze presentation, surgical approach, neurological outcomes, complications, recurrence rates and predictive factors.

RESULTS

There were 154 patients. The follow-up was 76.8 months on average (range 8-380 months). Gross total resection (GTR) was achieved in 40 (26.0%) patients, subtotal resection (STR) in 101 (65.6%), and partial resection in 13 (8.3%). Six (2.6%) perioperative deaths occurred. The 5-year, 10-year and 15-year progression-free survival (PFS) of GTR and STR with radiation therapy (RT) was similar (100%, 90% and 75%). PFS of STR without adjuvant radiation was associated with progression in 71%, 51% and 31%, respectively. Anterior petrosectomy and combined petrosectomy were associated with higher postoperative CN V and CN VI deficits compared to the retrosigmoid approach. The latter had a significantly higher risk of CN VII, CN VIII and LCN deficit. Temporal lobe dysfunction (seizure and aphasia) were significantly associated with the anterior petrosectomy approach.

CONCLUSIONS

Our study shows that optimal subtotal resection of PCMs associated with postoperative RT or stereotactic radiosurgery results in long-term tumor control to equivalent radical surgery. Case selection and appropriate intraoperative judgement are required to reduce the morbidity.

Combined toxic effects and DNA damage to two plant species exposed to binary metal mixtures (Cd/Pb)

Acute and long-term (3-, 10- and 56-day exposure) laboratory toxicity tests were carried out to assess the individual and combined toxic effects of cadmium (Cd) and lead (Pb) in Brassica oleracea and Trifolium repens. In addition to morphological parameters, this work also used comet assay to address endpoints in relation to genotoxicity. Bioaccumulation was measured to demonstrate the influence of the mixture on the concentrations of each metal in the plant. The statistical method reported by Ince et al. (1999) was used to evaluate the types of interaction between Cd and Pb in each treatment and concerning their combined effect. This study concludes that the combined effects of binary metal combinations of Cd/Pb on morphological parameters are most often additive, sometimes antagonistic and more rarely synergistic, thus extending the findings of previous publications on this subject. DNA damage analysis revealed concentration- and time-dependent interactions. Synergistic effects of mixed metals (more breaks than individually applied metals) are observed in T. repens after a short exposure. Antagonistic effects are statistically significant after 10 days-exposure, suggesting competition between metals. At 56 days, the rate of DNA damage observed in plants exposed to the Cd/Pb mixture was similar to that measured in plants exposed to lead only and was significantly lower than the rate of DNA damage induced by Cd. This supports the idea that there may be competition between metals and also strengthens the hypothesis that long-term reparation mechanisms may be implemented. Cd/Pb co-exposure does not significantly influence the bioaccumulation of each metal. It is nevertheless important to note that a statistically significant 'interaction' is not necessarily biologically relevant and should therefore be considered with caution when assessing heavy metals combined effects.

Microsurgical anatomy of the fourth ventricle

Anatomical description of the fourth ventricle is essential for an accurate understanding of its related tumoral pathologies and surgical approach respecting cerebellar and brainstem structures. Numerous cadaver pictures illustrate this chapter which contains V4 floor and roof description and its vascularization.

Surgical anatomy for hemifacial spasm

Classically in the cerebello-pontine angle the facial (CN VII) and vestibular-cochlear (CN VIII) nerves should run parallel with the anterior inferior cerebellar artery, whereas the lower nerves (CN IX-XI) continue with the posterior-inferior-cerebellar artery (PICA). In fact, this is not always true, particularly when dealing with hemispasm surgery where the relationships between CN VII, CN VIII and PICA are often different and closer. Knowledge of anatomical bases in surgical situation will help neurosurgeons to appreciate anatomical nuances, that are important to increase effectiveness and safety of hemifacial spasm surgery.

Two miscarriages, consecutive or non-consecutive, does it change something?

OBJECTIVES

To assess the rate of anomalies in the etiological evaluation of patients presenting recurrent early miscarriages (RM) according to miscarriage chronology (number of miscarriages, history of live birth and succession of RM).

METHODS

Retrospective single centre study including RM, defined as at least 2 miscarriages at less than 14 weeks of gestation (WG) between the 1st January 2012 and the 31st December 2015. Clinical data and etiological evaluation include blood glucose levels, screening for antiphospholipid syndrome (APS), endocrine assessment, vitamin levels, pelvic imaging, karyotyping of both partners, chronic endometritis and thrombophilia screening.

RESULTS

Two hundred and eighty-eight patients were included over this period, 118 (41%) patients had no history of live birth. Two hundred and twenty-three (77%) patients had consecutive RM and 65 (22%) patients had non-consecutive RM. For consecutive RM, 62,8% had thrombophilic disorders versus 69,8% for non-consecutive RM (P>0,05); 44,7% had endocrine disorders or vitamin deficiencies versus 39,7%; 34,6% of patients with consecutive RM had uterine anomalies versus 45,5% respectively. No difference was found depending on the recurrence of RM or the history of live birth (P>0.05) apart from the age of the patient. Fifty-nine (17.4%) patients had uterine anomalies. There are 24 chronic endometritis on 31 biospsies performed. Seventy-eight (27%) patients were offered treatment. Ninety-four (90%) patients showed good therapy compliance. Eighty-one (78%) patients became pregnant.

CONCLUSION

An etiological evaluation provides, for over half of the cases, an etiology or the identification of risk factors responsible for RM, as well as in some cases offering an adapted, efficient, therapeutic approach. This evaluation should be offered regardless of the obstetric history of the patient.

Lesson to be remembered from a skull base tumor

The natural history of giant prolactinomas is not known. While it is commonly accepted that the enlargement of microadenoma is rare and more limited than macroadenoma, it is so far uncommon that macroadenoma progress to giant adenoma. Thus, spontaneous enlargement of adenomas is poorly documented. We report the unusual history of undiagnosed microprolactinoma, revealed 12years later at the stage of a giant adenoma presenting as a skull base tumor. This unique observation provides information on the natural history of giant adenomas and arguments for particular attention to microadenomas with signs of invasion. Moreover, this clinical case highlights the need for a prolactin dosage for all midline skull base tumors.

Extradural resection of the anterior clinoid process: How I do it

BACKGROUND

The anterior clinoid process shares a close relationship with the optic canal, the internal carotid artery, the superior orbital fissure and the cavernous sinus. These structures may be involved in diseases whose surgical exposure requires prior clinoid process resection.

METHOD

Based on operative cases we describe the different steps of this surgical technique and illustrate our surgical procedure with a video. Dividing the orbito-temporal periosteal fold is a key-step in order to optimize the elevation of the periosteal dural layer at the level of the superior orbital fissure to expose the contours of the anterior clinoid process. The clinoid tip is removed after "debulking" the bony content inside the anterior clinoid process in order to leave only a thin shell of bony contour. The bony shell is then detached from the dura, twisted and pulled out. The indications and limitations of the technique are presented.

CONCLUSION

The extradural approach of the anterior clinoid process totally provides a full resection of the anterior clinoid process and safety for the paraclinoid space structures. Meticulous stepwise bony resection and optimized dura opening contribute to reduce the risk inherent to this technique.

The First 2 Years of Activity of a Specialized Organ Procurement Center: Report of an Innovative Approach to Improve Organ Donation

The number of patients requiring organ transplants continues to outgrow the number of organs donated each year. In an attempt to improve the organ donation process and increase the number of organs available, we created a specialized multidisciplinary team within a specialized organ procurement center (OPC) with dedicated intensive care unit (ICU) beds and operating rooms. The OPC was staffed with ICU nurses, operating room nurses, organ donor management ICU physicians, and multidisciplinary staff. All organ donors within a designated geographic area were transferred to and managed within the OPC. During the first 2 years of operation, 126 patients were referred to the OPC. The OPC was in use for a total of 3527 h and involved 253 health workers. We retrieved 173 kidneys, 95 lungs, 68 livers, 37 hearts, and 13 pancreases for a total of 386 organs offered for transplantation. This translates to a total of 124.6 persons transplanted per million population, which compares most favorably to recently published numbers in developed countries. The OPC clearly demonstrates potential to increase the number of deceased donor organs available for transplant. Further studies are warranted to better understand the exact influence of the different components of the OPC on organ procurement.

"Giant cell reparative tumor: An exceptional differential diagnosis for a lytic lesion of the temporal bone"

BACKGROUND AND IMPORTANCE

Giant cell reparative granuloma is a very rare benign osteolytic lesion. It typically arises in the mandible and rarely involves the skull.

CLINICAL PRESENTATION

A 25-year-old male was admitted in August 2002 for a painless left preauricular mass of several months duration. CT scan revealed an osteolytic extradural lesion located in the temporal bone, with extension to infratemporal fossa. We performed a surgical partial resection of the tumour via a frontotemporal approach. At 36 months after surgery, the lesion continued growth and subsequently we decided to perform a preauricular infratemporal approach. After a ten year-follow-up, the patient remained asymptomatic and a small tumour remnant was visible and stable.

CONCLUSION

Giant cell reparative granulomas that originate from the temporal bone are exceptional. There are no typical radiological features of this disease. Diagnosis is confirmed by analysis of the surgical specimen. Tumor growth requires surgical resection.

Photosensitized Formation of Secondary Organic Aerosols above the Air/Water Interface

In this study, we evaluated photosensitized chemistry at the air-sea interface as a source of secondary organic aerosols (SOA). Our results show that, in addition to biogenic emissions, abiotic processes could also be important in the marine boundary layer. Photosensitized production of marine secondary organic aerosol was studied in a custom-built multiphase atmospheric simulation chamber. The experimental chamber contained water, humic acid (1-10 mg L(-1)) as a proxy for dissolved organic matter, and nonanoic acid (0.1-10 mM), a fatty acid proxy which formed an organic film at the air-water interface. Dark secondary reaction with ozone after illumination resulted in SOA particle concentrations in excess of 1000 cm(-3), illustrating the production of unsaturated compounds by chemical reactions at the air-water interface. SOA numbers via photosensitization alone and in the absence of ozone did not exceed background levels. From these results, we derived a dependence of SOA numbers on nonanoic acid surface coverage and dissolved organic matter concentration. We present a discussion on the potential role of the air-sea interface in the production of atmospheric organic aerosol from photosensitized origins.

Antioxidant defense gene analysis in Brassica oleracea and Trifolium repens exposed to Cd and/or Pb

This study focused on the expression analysis of antioxidant defense genes in Brassica oleracea and in Trifolium repens. Plants were exposed for 3, 10, and 56 days in microcosms to a field-collected suburban soil spiked by low concentrations of cadmium and/or lead. In both species, metal accumulations and expression levels of genes encoding proteins involved and/or related to antioxidant defense systems (glutathione transferases, peroxidases, catalases, metallothioneins) were quantified in leaves in order to better understand the detoxification processes involved following exposure to metals. It appeared that strongest gene expression variations in T. repens were observed when plants are exposed to Cd (metallothionein and ascorbate peroxidase upregulations) whereas strongest variations in B. oleracea were observed in case of Cd/Pb co-exposures (metallothionein, glutathione transferase, and peroxidase upregulations). Results also suggest that there is a benefit to use complementary species in order to better apprehend the biological effects in ecotoxicology.

Lower third clivus and foramen magnum intradural tumor removal: The plea for a simple posterolateral approach

BACKGROUND

Anterior or anterolateral lesions of the lower third clivus and/or foramen magnum require a surgical exposure that provides a clear visualization of both pathological and normal anatomy without retraction of neural or vascular structures. The posterolateral approach permits access to the anterolateral intradural aspect of the brainstem. The aim of this study was to stress that there is no need for vertebral artery transposition, occipital condyle drilling, occipitocervical fixation or trans-oro-pharyngeal access to remove these lesions.

METHODS

All five consecutive patients treated surgically for an intradural foramen magnum lesion in the Department of Neurosurgery at Angers University Hospital, between May 2012 and January 2015, were included in this retrospective study. In 4 cases, patients were referred to us for a second opinion after an initial surgical proposal at another institution. For all patients, the data collected were age at diagnosis, clinical signs, and quality of rostral and caudal exposure of the lesion, quality of resection, complications and postoperative neurological deficits.

RESULTS

All patients were operated on with a control of the rostrocaudal part of the lesion, without touching the vertebral artery, or the use of occipital condyle drilling. There was no need for occipitocervical fixation. Total resection was achieved in 4 cases, subtotal resection in one. All had watertight dural closure with no dural patch, or postoperative neurological deficits. No recurrence occurred between 6 and 30 months after surgery.

CONCLUSION

Based on these results, the posterolateral approach was a simple, effective and safe procedure for anterior and anterolateral intradural lesion of the foramen magnum.