[Comparison of foetal and neonatal mortality of monochorionic monoamniotic and monochorionic biamniotic twin pregnancies]

OBJECTIVES

To compare the mortality of monochorionic-monoamniotic (MCMA) and monochorionic-biamniotic (MCBA) twin pregnancies, from 14weeks of gestation to 28th day of life, before and after exclusion of major congenital malformations.

METHODS

We conducted a retrospective cohort study in two level 3 maternity units of the Hospices civils de Lyon (France) including all patients with a monochorionic twin pregnancy between January 2013 and December 2020. We excluded TRAP sequences and conjoined twins.

RESULTS

A total of 38 MCMA and 658 MCBA pregnancies were included. We showed an increase in overall mortality in the MCMA group compared to the MCBA group (31.6% versus 16.4%, P=0.03) even after exclusion of major congenital malformations (20.3% versus 9.5%, P=0.01). The main cause of mortality found in the MCMA group was the occurrence of unexpected IUGR.

CONCLUSIONS

MCMA pregnancies have a higher foetal and neonatal mortality rate than MCBA pregnancies even after exclusion of congenital malformations related to the occurrence of unexpected MFIU.

Identification of a novel type of glucose dehydrogenase involved in the mineral weathering ability of Collimonas pratensis strain PMB3(1)

The exact molecular mechanisms as well as the genes involved in the mineral weathering (MW) process by bacteria remain poorly characterized. To date, a single type of glucose dehydrogenase (GDH) depending on a particular co-factor named pyrroloquinoline quinone (PQQ) is known. These enzymes allow the production of gluconic acid through the oxidation of glucose. However, it remains to be determined how bacteria missing PQQ-dependent GDH and/or the related pqq biogenesis genes weather minerals. In this study, we considered the very effective mineral weathering bacterial strain PMB3(1) of Collimonas pratensis. Genome analysis revealed that it does not possess the PQQ-based system. The use of random mutagenesis, gene complementation and functional assays allowed us to identify mutants impacted in their ability to weather mineral. Among them, three mutants were strongly altered on their acidification and biotite weathering abilities (58% to 75% of reduction compared to WT) and did not produce gluconic acid. The characterization of the genomic regions allowed noticeably to the identification of a Glucose/Methanol/Choline oxidoreductase. This region appeared very conserved among collimonads and related genera. This study represents the first demonstration of the implication of a PQQ-independent GDH in the mineral weathering process and explains how Collimonas weather minerals.

Effects of Rhythmic Sensory Stimulation on Ehlers-Danlos Syndrome: A Pilot Study

Ehlers-Danlos syndrome (EDS) is a connective tissue disorder characterized by joint hypermobility and skin extensibility and is often accompanied by chronic pain. Rhythmic sensory stimulation (RSS) can be defined as the stimulation of the senses in a periodic manner within a range of low frequencies. Music plus sound delivered through a vibroacoustic device is a form of RSS and has demonstrated utility in managing pain. In this current study, we conducted an open-label pilot study of 15 patients with hypermobile EDS using RSS as the intervention. Posttreatment improvements were seen in 11 of the 15 patients (73%), whereas 3 of the 15 patients (20%) experienced worse outcomes. Of the 14 patients that completed the experiment, 6 participants (43%) were classified as "responders" to the device while 8 participants (57%) were classified as "nonresponders." Responders demonstrated significant improvements in pain interference (51.5 ± 16 preintervention vs. 43.5 ± 16.4 postintervention BPI score) and depression symptoms (34.0 ± 15.9 preintervention vs. 26.8 ± 12.1 postintervention CESD score). Poststudy interviews confirm the improvements of pain interference, mood, and bowel symptoms. Furthermore, analysis of medical conditions within the responder group indicates that the presence of depression, anxiety, irritable bowel syndrome, and fibromyalgia may indicate a greater likelihood for patients to benefit with vibroacoustic applications. These results indicate a possible potential for RSS, delivered using a vibroacoustic device, in managing pain-related symptoms. Further research is necessary to elucidate the exact mechanism behind the physiological benefits of RSS.

Pediatric neurolisteriosis: A diagnosis to consider even in the absence of immunodeficiency

Neurolisteriosis is known to affect vulnerable groups, for example neonates or children with immunodeficiency. This is a key point of the current clinical guidelines regarding pediatric meningitis. We report a rare case of neurolisteriosis in an immunocompetent infant, without the typical signs of listeriosis, which led to a delay in administering the appropriate antibiotherapy. This case illustrates the clinical heterogeneity of neurolisteriosis and the relevance of appropriate polymerase chain reaction (PCR) tests when the clinical presentation differs from the current guidelines. This case also reminds us that raw or unpasteurized milk-based food products pose a risk even in immunocompetent infants or children.

A parallel randomized controlled trial examining the effects of rhythmic sensory stimulation on fibromyalgia symptoms

This double-blind, two-arm parallel randomized controlled trial investigated the effects of gamma-frequency rhythmic sensory stimulation on fibromyalgia. We were interested in whether rhythmic sensory stimulation would promote significant changes in fibromyalgia and associated symptoms, and whether treatment effects would differ between two distinct treatment parameters. Fifty patients with a formal diagnosis of fibromyalgia were randomly assigned to two test groups. One group received vibrotactile stimulation from a continuous sine wave single-frequency stimulation (40 Hz) for 30 minutes, five days per week, over five weeks, concomitant with usual care. The second group completed the same treatment protocol but received a different stimulation, consisting of random and intermittent complex wave gamma-range vibrotactile stimulation. Fibromyalgia symptoms, pain severity and interference, depression symptoms, quality of life and sleep quality were assessed at baseline and post-intervention. Results indicated that there were statistically significant changes from baseline to post-treatment in measures of fibromyalgia symptom severity, pain interference, depression, and sleep quality. However, treatment outcomes did not differ significantly between groups. These findings provide preliminary evidence that gamma-frequency rhythmic vibroacoustic stimulation may decrease fibromyalgia symptoms and ease associated comorbidities, opening new avenues for further investigation of the effects of rhythmic sensory stimulation on chronic pain conditions.

3D Angiography

To evaluate the interest of 3D angiography in the diagnosis, treatment and follow-up of aneurysms with special regard with endovascular GDC treatment. Spin angiography with 44 subtracted views (512×512 image matrix) is first acquired with a rotation of a C-arm through 200 degrees at 40° per second in an angiographic room prototype LCV+ single plane (GEMS). 3D reconstruction ART (Algebraic Reconstruction Technique) is automatically applied and interactive visualisation of the 3D angiography is available on a workstation (UltraSparc 2, Sun microsystems) 10 minutes after the spin angiography acquisition. 3D angiography is displayed in MIP, surface rendering and endovascular views (virtual angioscopy).

52 2D and 3D angiographies were performed in 40 patients with 49 intracranial aneurysms whith the same protocol of acquisition (AP, lateral and spin angiography). Each 3D angiography (MIP and surface rendering) was analysed by 2 senior radiologists and compared with the corresponding 2D angiographies (AP, lateral and spin views). Artefacts due to GDC were present in 24 cases, but bothering in only 12 cases. Analysis of the aneurysm was better in MIP than in 2D in 32 cases, equivalent in 18 and worse in 2 due to patient movements during acquisition. Surface rendering gave additional information in 29 cases. The impact was judged important for decision making or choice of treatment in 25 cases. 3D angiography improves the analysis of the aneurysms, gives crucial information to make the decision for treatment and is now routinely used in our institution for the diagnosis of intracranial aneurysms and follow-up after GDC treatment.

Influence of Temperature on Embolisation with Cyanoacrylate

We evaluated the influence of temperature on the viscosity of mixtures with different histoacryl/lipiodol concentrations and on injection control, to test the radiological visualization of these mixtures. A viscosimeter was used to measure the viscosity of different histoacryl and lipiodol combinations at various temperatures. After introduction of these blends into the polyethylene tubes, their radiological densities were evaluated by means of CT and DSA. Viscosity was found to be directly proportional to the percentage of lipiodol and inversely proportional to the temperature. By digital subtraction, the mixtures were still visible when the percentage of histoacryl reached 90%. Warming histoacryl and lipiodol mixtures to a temperature that is close to 40° C decreases the mixture's viscosity significantly and makes the injection easier to manage. Tantalum and tungsten powders do not necessarly have to be added to visualize mixtures containing less than 90% histoacryl.

Combined Endovascular Stenting and Endosaccular Coiling for the Treatment of a Wide-Necked Intracranial Vertebral Aneurysm

We describe a clinical case of the combined application of endovascular stent placement and GDCoils packing in the management of a ruptured wide necked intracranial aneurysm.

A 27-year-old man had a subarachnoid haemorrhage secondary to the rupture of a large wide necked left vertebral aneurysm. This aneurysm was judged to be inoperable. A functional occlusion test failed because of poor collateral flow and combined stenting and coiling was used to occlude the aneurysm with preservation of the parent artery.

A femoral approach was used. An 18 mm long ACS® Duet stent was placed across the base of aneurysm and expanded to 4mm to act as a buttress. A microcatheter was then advanced through the stent mesh and GDC's were deposited for occlusion.

This technique provides new possibilities for wide-necked intracranial aneurysms. Further studies are required on the mechanical and thrombogenic properties of stents and on the long-term follow-up, but this technology may play a role in some cases of aneurysm treatment.

The properties of new epoxy networks swollen with ionic liquids

In this work, ionic liquids based on trihexyl(tetradecyl)phosphonium associated with bis(2,4,4-trimethylpentyl)phosphinate [TMP] and dicyanamide [DCA] counter anions were used as reactive additives within epoxy/amine networks.

Endovascular treatment of ACom intracranial aneurysms. Report on series of 280 patients

The immediate and long-term outcomes, complications, recurrences and the need for retreatment were analyzed in a series of 280 consecutive patients with anterior communicating artery aneurysms treated with the endovascular technique. From October 1992 to October 2001 280 patients with 282 anterior communicating artery aneurysms were addressed to our center. For the analysis, the population was divided into two major groups: group 1, comprising 239 (85%) patients with ruptured aneurysms and group 2 comprising of 42 (15%) patients with unruptured aneurysms. In group 1, 185 (77.4%) patients had a good initial pre-treatment Hunt and Hess grade of I-III. Aneurysm size was divided into three categories according to the larger diameter: less than 4 mm, between 4 and 10 mm and larger than 10 mm. The sizes of aneurysms in groups 1 and 2 were identical but a less favorable neck to depth ratio of 0.5 was more frequent in group 2. Endovascular treatment was finally performed in 234 patients in group 1 and 34 patients in group 2. Complete obliteration was more frequently obtained in group 2 unlike a residual neck or opacification of the sac that were more frequently seen in group 1. No peri-treatment complications were recorded in group 2. In group 1 the peri-treatment mortality and overall peri-treatment morbidity were 5.1% and 8.1% respectively. Eight patients (3.4%) in group 1 presented early post treatment rebleeding with a mortality of 88%. The mean time to follow-up was 3.09 years. In group 1, 51 (21.7%) recurrences occurred of which 14 were minor and 37 major. In group 2, eight (23.5%) recurrences occurred, five minor and three major. Two patients (0.8%) presented late rebleeding in group 1. Twenty-seven second endovascular retreatments were performed, 24 (10.2%) in group 1 and three (8.8%) in group 2, seven third endovascular retreatments and two surgical clippings in group 1 only. There was no additional morbidity related to retreatments. Endovascular treatment is an effective method for the treatment of anterior communicating artery aneurysms allowing late rebleeding prevention. Peri-treatment rebleeding warrants caution in anticoagulation management. This is a single center experience and the follow-up period is limited. Patients should be followed-up in the long-term as recurrences may occur and warrant additional treatment.

Model of a vascular C-arm for 3D augmented fluoroscopy in interventional radiology

This paper deals with the modeling of a vascular C-arm to generate 3D augmented fluoroscopic images in an interventional radiology context. A methodology based on the use of a multi-image calibration is proposed to assess the physical behavior of the C-arm. From the knowledge of the main characteristics of the C-arm, realistic models of the acquisition geometry are proposed. Their accuracy was evaluated and experiments showed that the C-arm geometry can be predicted with a mean 2D reprojection error of 0.5 mm. The interest of 3D augmented fluoroscopy is also assessed on a clinical case.

Suivi iconographique d’un état de mal épileptique prolongé

We report the MR imaging findings in a 20 year old woman with status epilepticus of more than 3 months duration following an episode of lymphocytic meningitis. Repeated MR examinations showed progressive symmetrical cortical lesions, followed by subcortical and basal ganglia lesions which evolved to cortical laminar necrosis and hemorrhagic necrosis with eventual subcortical cerebral atrophy. This case has similarities with animal status epilepticus models. Biological investigations were all negative. This suggests that the brain lesions may be related to the prolonged status epilepticus.

Standards of Practice in Interventional Neuroradiology or Endovascular Neurosurgery. WFITN Site Conditions and Technical Operational Guidelines

with the working group composed of: S. Bracard, J. Byrne, L. Feng, O. Flodmark, A. Goulao, M. Leonardi, M. Mawad, J. Mishra, J. Moret, M. Negoro, R. Piske, B. Richling, G. Rodesch, J. Ruscalleda, K. terBrugge, A.Valavanis.

[Risks and responsibilities in diagnostic and interventional radiology. Ethical and medicolegal considerations]

Medical risk management has one main purpose: to ensure the safety of care. The law of March 2002 has generated a true cultural revolution. The radiologist is involved with new and difficult areas of medical liability due to technical advances, the increasing number of imaging techniques, the increasing complexity of imaging techniques, their efficiency and the need for multidisciplinary approach. Imaging recommendations requiring increasing levels of technical and clinical skills. The radiologist is liable with regards to the indications of imaging studies, and also with regards to informed consent. The prevention of medicolegal problems is achieved by competency, which must be combined to good liability insurance and ongoing vigilance supported by appropriate continuous medical education.

Neuroradiologie de la maladie de rendu osler

Hereditary Hemorrhagic telangiectasia is an autosomal dominant vascular disorder with high penetrance and variable expressivity. Most cases are caused by mutations in the endoglin gene on chromosome 9 (HHT type 1) or the activin receptor-like kinase 1 gene on chromosome 12 (HHT type 2). HHT is characterized by mucocutaneous telangiectases and visceral arteriovenous malformations (AVMs). Neurological complications occur in 8 to 10% of the patients. Brain ischemia or abscess are often associated with pulmonary arteriovenous fistula. Cerebral or spinal arteriovenous malformations are frequent but have a lower risk of haemorrhage than sporadic AVMs and routine screening should not be practiced in adult patients. Routine screening should be discussed for children with a familial history of cerebral haemorrhage and/or HHT type 1.

Symptomatic Radionecrosis after AVM Stereotactic Radiosurgery. Study of 16 Consecutive Patients

SUMMARY

The purpose of our study was to analyze the outcome of symptomatic radionecrosis following stereotactic radiosurgery for brain arteriovenous malformations. Of 225 patients treated by linear accelerator radiosurgery for brain AVM, 16 (7,1%) presented post-radiosurgery symptomatic radionecrosis on a mean follow-up period of 50 months (range 1-123 months). Once diagnosed with radionecrosis, 14 of 16 patients were subjected to high dose corticotherapy consisting of escalating doses of dexamethasone for several weeks. The mean interval of occurrence of new symptoms was 11.6 months post-radiosurgery (range 6-20 months). The mean time of follow-up was 2.9 years post radiotherapy ranging from seven months to eight years. Of the 16 patients with symptomatic radionecrosis, 11 (68,75%) showed complete resolution of symptoms while five (31,25%) showed improvement but still presented a neurological deficit at the closing date of the study. At the closing date, 11 patients (68.75%) had angiographically completely obliterated arteriovenous malformations while another two patients had an obliteration of 95% to 98% and one patient had a 98% obliteration with development of a new contralateral AVM. In our series, symptomatic radionecrosis occurred in 7.1% of patients treated with stereotactic radiosurgery for brain AVM. These patients where subjected to a prompt, high dose corticosteroid treatment and most presented symptom resolution or improvement with a fair obliteration rate, offering protection from bleeding. Permanent neurologic deficits attributable to radionecrosis occurred in 2.2% of our patient population treated with stereotactic radiosurgery for brain AVM.

[Medicolegal aspects in neuroradiologic emergencies]

Naturally, neuroimaging emergencies are a component of the global subject of emergencies that have for several years been a frequent subject in the press. The current situation is the consequence of the evolution of ideas from contractual liability to the frequently discussed principle of precaution. Examples offered by the daily practice allow to emphasize the main difficulties: diagnosis of headaches, seizure episode on public roads, head trauma, stroke... The medical liability of the neuroradiologist is not the same for diagnostic or interventional neuroradiology; it can sometimes be shared with other physicians. This liability includes the indication, the quality of the diagnosis, the information of the patient and relatives, the communication of results with other physicians, the maintenance of the equipment... Knowledge of potential pitfalls allows preventive measures including competence of the neuroradiologist, informed patient consent, and written precise protocols are the most important. However, according to the evolution of our societies, it is likely that it will become increasingly difficult to achieve a professional neuroradiology career without being questioned; it is thus advisable to be prepared for such eventuality.

Mélanome primitif intrarachidien

Intra spinal primary melanoma is a rare entity. We report a new case, atypical in relation to its primary radicular location, and to its early metastatic intradural and extra-medullary location, six months later. MRI is the more valuable examination, showing a spontaneously hyper-intense lesion on T1-weighted MR images, intense enhancement after gadolinium administration, and decreased signal on T2-weighted MR images, thus suggesting a diagnosis of melanocytic or hemorrhagic lesion. Signal abnormalities are not specific and definitive diagnosis is established after histological analysis.