Advances in stereotactic navigation for pelvic surgery.

BACKGROUND: Stereotactic navigation could improve the quality of surgery for rectal cancer. Critical challenges related to soft tissue stereotactic pelvic navigation include the potential difference in patient anatomy between intraoperative lithotomy and preoperative supine position for imaging. The objective of this study was to determine the difference in patient anatomy, sacral tilt, and skin fiducial position between these different patient positions and to investigate the feasibility and optimal set-up for stereotactic pelvic navigation. METHODS: Four consecutive human anatomical specimens were submitted to repeated CT-scans in a supine and several degrees of lithotomy position. Patient anatomy, sacral tilt, and skin fiducial position were compared by means of an image computing platform. In two specimens, a 10-degree wedge was introduced to reduce the natural tilt of the sacrum during the shift from supine to lithotomy position. A simulation of laparoscopic and transanal surgical procedures was performed to assess the accuracy of the stereotactic navigation. RESULTS: An up-to-supracentimetric change in patient anatomy was noted between different patient positions. This observation was minimized through the application of a wedge. When switching from supine to another position, sacral retroversion occurred independent of the use of a wedge. There was considerable skin fiducial motion between different positions. Accurate stereotactic navigation was obtained with the least registration error (1.9 mm) when the position of the anatomical specimen was registered in a supine position with straight legs, without pneumoperitoneum, using a conventional CT-scan with an identical specimen positioning. CONCLUSION: The change in patient anatomy is small during the sacral tilt induced by positional changes when using a 10-degree wedge, allowing for an accurate stereotactic surgical navigation. This opens up new promising opportunities to increase the quality of surgery for rectal cancer cases where it is difficult or impossible to identify and dissect along the anatomical planes.

A step towards stereotactic navigation during pelvic surgery: 3D nerve topography.

BACKGROUND: Long-term morbidity after multimodal treatment for rectal cancer is suggested to be mainly made up by nerve-injury-related dysfunctions. Stereotactic navigation for rectal surgery was shown to be feasible and will be facilitated by highlighting structures at risk of iatrogenic damage. The aim of this study was to investigate the ability to make a 3D map of the pelvic nerves with magnetic resonance imaging (MRI). METHODS: A systematic review was performed to identify a main positional reference for each pelvic nerve and plexus. The nerves were manually delineated in 20 volunteers who were scanned with a 3-T MRI. The nerve identifiability rate and the likelihood of nerve identification correctness were determined. RESULTS: The analysis included 61 studies on pelvic nerve anatomy. A main positional reference was defined for each nerve. On MRI, the sacral nerves, the lumbosacral plexus, and the obturator nerve could be identified bilaterally in all volunteers. The sympathetic trunk could be identified in 19 of 20 volunteers bilaterally (95%). The superior hypogastric plexus, the hypogastric nerve, and the inferior hypogastric plexus could be identified bilaterally in 14 (70%), 16 (80%), and 14 (70%) of the 20 volunteers, respectively. The pudendal nerve could be identified in 17 (85%) volunteers on the right side and in 13 (65%) volunteers on the left side. The levator ani nerve could be identified in only a few volunteers. Except for the levator ani nerve, the radiologist and the anatomist agreed that the delineated nerve depicted the correct nerve in 100% of the cases. CONCLUSION: Pelvic nerves at risk of injury are usually visible on high-resolution MRI with dedicated scanning protocols. A specific knowledge of their course and its application in stereotactic navigation is suggested to improve quality of life by decreasing the likelihood of nerve injury.

Relapse of Enterococcus hirae prosthetic valve endocarditis.

Enterococcus hirae, a gram-positive bacterium, is a rare isolate in clinical specimens. We report an unusual case of a relapse of prosthetic valve endocarditis due to E. hirae 6 months after the initial episode. Clonal relationship was proven by genomic analysis.

Change of depressive symptoms in a French nine-year longitudinal study of aging: Gender differences and relationships between social support, health status and depressive symptoms.

OBJECTIVES: The aims of this study were to examine the trajectory of depressive symptoms among older French people, to investigate the role of gender in the developmental trajectory of depressive symptoms and to explore whether the linear increase in depressive symptoms might be accentuated or attenuated at time points during which the older adults' scores on social support and health satisfaction scales were higher than their individual averages. METHODS/MATERIALS: Data were used from a subsample of older adults living at home who participated in a longitudinal study initiated by researchers from the University of Tours. They were collected at five time points over a 9-year period (T1: 2003; T2: 2005; T3: 2007; T4: 2009; T5: 2011). This study included 707 participants, and multilevel growth curve analysis was used on measures of depressive symptoms, gender differences, social support and health satisfaction. RESULTS: Results indicated (1) a significant positive linear effect of age on depressive symptoms; (2) that women reported significantly higher scores of depressive symptoms than men at 63 years old (i.e., intercept) and that this gender difference remained constant across age; (3) that the slope of depressive symptoms appeared to increase at time points during which participants had higher levels of social support and to decrease when they had greater health satisfaction. CONCLUSION: This study provides pertinent information about the change of depressive symptoms in older people living at home and particularly highlights the interest in studying gender, social support and health satisfaction.

Long-term evolution of a nosocomial outbreak of Pseudomonas aeruginosa producing VIM-2 metallo-enzyme.

From April 1996 to July 2004, an outbreak of metallo-beta-lactamase-positive (MBL) Pseudomonas aeruginosa occurred in the haematology ward at Nantes University Hospital in France. Fifty-nine patients were carriers of VIM-2-positive strains of whom 14 were infected (mostly urinary tract infections and pneumonia). Pulsed-field gel electrophoresis identified related isolates demonstrating resistance to all beta-lactams, aminoglycosides, fluoroquinolones, fosfomycin, rifampicin but not colistin. The bla(VIM-2) gene responsible for VIM-2 MBL was not plasmid-encoded but part of a novel type of class 1 integron. VIM-2-positive strains were mostly from urine samples and clinical data suggest that in the absence of therapeutic guidelines, piperacillin-tazobactam or aztreonam may be a reliable choice for treating infections with MBL-producing strains.

[Risk stratification in atrial and ventricular arrhythmias]. / Stratification du risque dans les troubles du rythme auriculaire et ventriculaire.

Atrial fibrillation, the most frequent arrhythmia, has a growing incidence with increasing age and the most important complication of the disease is thromboembolic events that may be prevented by antivitamin K. They are the most efficient therapeutic class for the prevention of these events but they are associated with an increased haemorrhagic risk leading to a reduced prescription in general practice. Optimisation of the management should be based on an individual evaluation of the thromboembolic and haemorrhagic risks, taking into account age, the presence of an associated heart disease, hypertension, diabetes, history of cerebrovascular event, history of previous haemorrhagic event and the ability to achieve a stable target INR. The challenge in ventricular arrhythmias lies in identifying a high risk of sudden death, mainly related to ventricular fibrillation. In patients with structural heart disease, left ventricular dysfunction is the strongest predictor of sudden death. Non invasive markers such as non sustained ventricular tachycardia, late ventricular potentials, decreased heart rate variability and baroreflex sensitivity, and repolarization altemans are further elements to assess risk. However, most of these markers have a poor positive predictive value and a low specificity. In patients with normal hearts, genetic predisposition may in the future identify high risk patients. The electrophysiologic study with programmed ventricular stimulation remains a costly and invasive method and only has a strong positive predictive value in ischemic cardiomyopathy. More precise algorithms for risk stratification are thus needed that may help the strategy of therapy with prophylactic implantable cardioverter defibrillator in the future.

[Indications for automatic implantable defibrillators in patients with the Brugada syndrome]. / Indications du défibrillateur cardiaque automatique implantable dans le syndrome de Brugada.

Brugada syndrome is a primary electrical cardiac disease characterized by an ST segment elevation in V1-V2 leads on surface ECG and an increased risk of polymorphic ventricular tachyarrhythmia (ventricular tachycardia and/or ventricular fibrillation). The objective of the treatment is to prevent sudden death and it therefore includes in some cases the implantation of an automatic implantable cardiac defibrillator (AICD). In secondary prevention (i.e. after a first episode of resuscitated ventricular fibrillation), the implantation of AICD is mandatory (indication of class 1 level A). In primary prevention (i.e. in patients without documented ventricular fibrillation), the guidelines are not definitively established. We may consider two different clinical situations. First, the patient complains from syncope and this justifies the implantation of an AICD. Second, the patient is asymptomatic and the physician has to discuss the implantation of an AICD. Two parameters should be analysed: the pattern of ECG and the result of right programmed ventricular stimulation. An evident ST segment elevation (>2 mm) is associated with a high risk of sudden death. Likewise, the inducibility of a ventricular tachycardia or fibrillation is considered at the present time as a factor linked to sudden death and justifies the implantation of an AICD. On the other hand, a normal resting ECG only associated with a provoked ST segment elevation by class I antiarrhythmic drug (flecainide) defines a group of patients with a low risk of sudden death, and these patients do not require the implantation of an AICD.

[Postmarketing surveillance in patients with cardiac pace-makers or automatic implantable defibrillators]. / Aspects généraux et réglementaires de la matériovigilance des stimulateurs et des défibrillateurs cardiaques.

This article includes an overview of the actual French control and regulation system of the safety alerts involving pacemakers and implantable cardioverter-defibrillator and an evaluation of the general information and trends about the characteristics of the reported incidents obtained in the last years in that field. The national security agencies have the mission to collect the data on safety and efficacy of medical devices but manufacturers, physicians and patients also have a role to play. The technical appreciation of the necessity of a notification is not easy in some cases but the lack of notification of a severe incident may lead to heavy penal consequences. If doubtful cases, one should keep in mind the spirit of these safety systems: a collective insurance against the risks related to the use of medical devices. In the 10 last years, the annual advisory rate was increased. The pacemakers were recalled more frequently than implantable cardioverter-defibrillators in absolute value but less frequently in relative value (advisories per 100 person-years). This increase may be related to the growing number of device implants and expanding indications for device therapy, to the increasing sophistication of the devices and to the modifications in the regulation aspects of these problems with a closer attention of users and physicians to the several types of malfunctions.

[Arrhythmias of primary hypertrophic cardiomyopathy]. / Arythmies de la cardiomyopathie hypertrophique primitive.

Primary hypertrophic cardiomyopathy is a genetic disease causing sarcomere dysfunction. The structural and functional myocardial changes combine to produce cardiac arrhythmias related to reentry phenomena and to triggered automatic activity. The commonest arrhythmias are atrial fibrillation and ventricular arrhythmias; junctional tachycardias via the bundle of Kent are rare. Atrial fibrillation and the Wolff-Parkinson-White syndrome are more commonly associated with certain genetic mutations. Their treatment is mainly based on medication with amiodarone or on radiofrequency ablation in cases of junctional tachycardia. Ventricular arrhythmias are mainly isolated ventricular extrasystoles and non-sustained ventricular tachycardia. The prognostic significance of the latter has been subject of debate for many years but recent studies report a poor prognosis with non-sustained ventricular tachycardia especially in the young patients. Sustained ventricular tachycardia and ventricular fibrillation, though life-threatening complications of hypertrophic cardiomyopathy, are rarely documented and justify implantation of an automatic defibrillator as the risk of recurrence is high. The main objective of the cardiologist in cases of primary hypertrophic cardiomyopathy is to identify the patient at high risk of sudden death. This requires analysis of several parameters: clinical, anatomical, haemodynamic, rhythmic, functional and genetic. The presence of at least two risk factors for sudden death justifies preventive measures. The implantation of an automatic defibrillator is the most reliable form of treatment.

[Pericardial effusion revealing cardiac amyloidosis in the course of rheumatoid arthritis]. / Epanchement péricardique révélateur d'une amylose cardiaque au cours de l'évolution d'une polyarthrite rhumatoïde.

Pericardial effusion is common in patients with rheumatoid arthritis. It is essentially a sign of pericardial involvement of the rheumatoid disease, but viral, bacterial and especially tuberculous pericarditis must not be excluded. Pericardial amyloidosis of the AA type is much less common and difficult to diagnose before cardiac biopsy even in cases of myocardial amyloidosis, as in the reported case, in which the classical association of microvoltage on the ECG and myocardial hypertrophy on echocardiography was absent. The absence of myocardial uptake of technetium-labelled pyrophosphates at myocardial scintigraphy and the absence of a restrictive profile on cardiac gamma-angiography were not suggestive of the diagnosis of amyloidosis. Pericardial and endomyocardial biopsy, justified by the negativity of the preceding investigations, provided an accurate histological diagnosis, a prognostic evaluation and was also useful for guiding management.

Septic arthritis due to a Sneathia species most closely related to Sneathia sanguinegens.

Sneathia sanguinegens is an infrequent bacterium in clinical specimens. We describe a case of right elbow septic arthritis due to a Sneathia species most closely related to S. sanguinegens in a young immunocompetent woman. S. sanguinegens has never been implicated in osteoarticular infections.

Biological cost of fluoroquinolone resistance in Escherichia coli implicated in polyclonal infection.

Polyclonal Escherichia coli strains were isolated in a transplanted patient who experienced successive septic shocks. Fluoroquinolone susceptible and resistant strains were corresponding to different PFGE fragment profiles. The gyrA S83L mutation was associated with a reduction in biological fitness. Resistant strain was selected by a long-term single use of ofloxacin.