Complications of guided surgery and immediate loading in oral implantology: a report of 12 cases

Objectives: The growing interest in minimally invasive surgery, together with the possibility of fitting prostheses with immediate function, have led to the development of software capable of planning and manufacturing a surgical guide and prosthesis that can be placed upon conclusion of the implant surgery step. The present study evaluates the surgical and prosthetic complications of implant treatment with the guided surgery technique, together with patient comfort during and after treatment. Patients and methods: A retrospective observational study was made of 19 patients with partially or totally edentulous upper and/or lower maxillae, involving the placement of a total of 122 implants. All cases were planned and operated upon with the guided surgery technique. Results: A total of 122 implants were placed in 14 males and 5 females. The intraoperative surgical complications comprised a lack of primary stability, while the postoperative complications consisted of infections and a lack of implant osteointegration. Ten implants failed. The prosthetic complications in turn comprised loosening of the provisional prosthesis screws, prosthesis tooth fracture, and a lack of passive fit of the immediate prosthesis. The degree of patient satisfaction was evaluated using a verbal scale. Conclusions: Implant restoration with the guided surgery technique and immediate functional loading is a predictable procedure, provided patient selection and the surgical technique are adequate, affording lesser postoperative morbidity and increased patient satisfaction thanks to the immediate restoration of esthetics and function

Structural control on present-day topography of a basement massif: the Central and Eastern Anti-Atlas (Morocco)

The Anti-Atlas basement massif extends South of the High Atlas, and, despite a very mild Cenozoic deformation, its altitude exceeds 1500m in large areas, reaching 3305m in Jbel Sirwa. Structural contours of the present elevation of a polygenic planation surface (the High Erosional surface) and of the base of Cretaceous and Neogene inliers have been performed to characterize the major tectonic structures. Gentle Cenozoic WSW-ENE- and N-Strending folds, of 60 to100km wavelength, reactivate Variscan structures, being the major contributors to the local topography of the Anti-Atlas. Reactivated thrusts of decakilometric to kilometric-scale and E-W trend involving the Neogene rocks exhibit a steep attitude and a small displacement, but they also produce a marked topographic expression. The resulting Cenozoic horizontal shortening along N-S sections across the Anti-Atlas is about 1%. The position of the major anticlinal hinges determines the location of the fluvial divides of the Warzazat basin and the Anti-Atlas, and a structural depression on one of these hinges (Jbel Saghro anticline) allowed the formerly endorheic Warzazat basin to drain southwards. The first Cenozoic structures generating local topography are of pre-mid Miocene age (postdated by 6.7Ma volcanic rocks at the Jbel Saghro), whereas the youngest thrust movements postdate the Pliocene sedimentary and volcanic rocks (involving 2.1Ma volcanic rocks at Jbel Sirwa). In addition to these features, the mean elevation of the Anti-Atlas at the regional scale is also the result of a mantle thermal anomaly reported in previous works for the entire Atlas system.

A systematic review of ultrasound-guided methods for brachial plexus blockade.

We systematically reviewed 25 randomised controlled trials of ultrasound-guided brachial plexus blockade that recruited 1948 participants: either one approach vs another (axillary, infraclavicular or supraclavicular); or one injection vs multiple injections. There were no differences in the rates of successful blockade with approach, relative risk (95% CI): axillary vs infraclavicular, 1.0 (1.0-1.1), p = 0.97; axillary vs supraclavicular, 1.0 (1.0-1.1), p = 0.68; and infraclavicular vs supraclavicular, 1.0 (1.0-1.1), p = 0.32. There was no difference in the rate of successful blockade with the number of injections, relative risk (95% CI) 1.0 (1.0-1.0), p = 0.69, for one vs multiple injections. The rate of procedural paraesthesia was less with one injection than multiple injections, relative risk (95% CI) 0.6 (0.4-0.9), p = 0.004.

Ultrasound-guided fine-needle aspiration of thyroid nodules: assessment of the ideal number of punctures

OBJECTIVE: To determine the number of punctures in fine-needle aspiration biopsies required for a safe cytological analysis of thyroid nodules. MATERIALS AND METHODS: Cross-sectional study with focus on diagnosis. The study population included 94 patients. RESULTS: The mean age of the patients participating in the study was 52 years (standard-deviation = 13.7) and 90.4% of them were women. Considering each puncture as an independent event, the first puncture has showed conclusive results in 78.7% of cases, the second, in 81.6%, and the third, in 71.8% of cases. With a view to the increasing chance of a conclusive diagnosis at each new puncture, two punctures have showed conclusive results in 89.5% of cases, and three punctures, in 90.6% of cases with at least one conclusive result. CONCLUSION: Two punctures in fine-needle aspiration biopsies of thyroid nodules have lead to diagnosis in 89.5% of cases in the study sample, suggesting that there is no need for multiple punctures to safely obtain the diagnosis of thyroid nodules.

Targeted cell elimination reveals an auxin-guided biphasic mode of lateral root initiation.

To sustain a lifelong ability to initiate organs, plants retain pools of undifferentiated cells with a preserved proliferation capacity. The root pericycle represents a unique tissue with conditional meristematic activity, and its tight control determines initiation of lateral organs. Here we show that the meristematic activity of the pericycle is constrained by the interaction with the adjacent endodermis. Release of these restraints by elimination of endodermal cells by single-cell ablation triggers the pericycle to re-enter the cell cycle. We found that endodermis removal substitutes for the phytohormone auxin-dependent initiation of the pericycle meristematic activity. However, auxin is indispensable to steer the cell division plane orientation of new organ-defining divisions. We propose a dual, spatiotemporally distinct role for auxin during lateral root initiation. In the endodermis, auxin releases constraints arising from cell-to-cell interactions that compromise the pericycle meristematic activity, whereas, in the pericycle, auxin defines the orientation of the cell division plane to initiate lateral roots.

Computed tomography-guided percutaneous biopsy of pancreatic masses using pneumodissection

Objective To describe the technique of computed tomography-guided percutaneous biopsy of pancreatic tumors with pneumodissection. Materials and Methods In the period from June 2011 to May 2012, seven computed tomography-guided percutaneous biopsies of pancreatic tumors utilizing pneumodissection were performed in the authors' institution. All the procedures were performed with an automatic biopsy gun and coaxial system with Tru-core needles. The biopsy specimens were histologically assessed. Results In all the cases the pancreatic mass could not be directly approached by computed tomography without passing through major organs and structures. The injection of air allowed the displacement of adjacent structures and creation of a safe coaxial needle pathway toward the lesion. Biopsy was successfully performed in all the cases, yielding appropriate specimens for pathological analysis. Conclusion Pneumodissection is a safe, inexpensive and technically easy approach to perform percutaneous biopsy in selected cases where direct access to the pancreatic tumor is not feasible.

Step-by-step of ultrasound-guided core-needle biopsy of the breast: review and technique

Ultrasound-guided core-needle biopsy has high sensitivity in the diagnosis of breast cancer. The present study is aimed at detailing the main steps of such procedure, including indications, advantages, limitations, follow-up and description of the technique, besides presenting a checklist including the critical steps required for an appropriate practice of the technique. In the recent years, an increasing number of patients have required breast biopsy, indicating the necessity of a proportional increase in the number of skilled professionals to carry out the procedures and histological diagnoses. A multidisciplinary approach involving the tripod clinical practice-radiology-pathology is responsible for the highest rate of accuracy of the technique and must always be adopted.

Image guided critical screw placement precision in the cervical spine : important or incidental? : results of a series of 91 consecutive cases using OVEM

Study design: A retrospective study of image guided cervical implant placement precision. Objective: To describe a simple and precise classification of cervical critical screw placement. Summary of Background Data: "Critical" screw placement is defined as implant insertion into a bone corridor which is surrounded circumferentially by neurovascular structures. While the use of image guidance has improved accuracy, there is currently no classification which provides sufficient precision to assess the navigation success of critical cervical screw placement. Methods: Based on postoperative clinical evaluation and CT imaging, the orthogonal view evaluation method (OVEM) is used to classify screw accuracy into grade I (no cortical breach), grade la (screw thread cortical breach), grade II (internal diameter cortical breach) and grade III (major cortical breach causing neural or vascular injury). Grades II and III are considered to be navigation failures, after accounting for bone corridor / screw mismatch (minimal diameter of targeted bone corridor being smaller than an outer screw diameter). Results: A total of 276 screws from 91 patients were classified into grade I (64.9%), grade la (18.1%), and grade II (17.0%). No grade III screw was observed. The overall rate of navigation failure was 13%. Multiple logistic regression indicated that navigational failure was significantly associated with the level of instrumentation and the navigation system used. Navigational failure was rare (1.6%) when the margin around the screw in the bone corridor was larger than 1.5 mm. Conclusions: OVEM evaluation appears to be a useful tool to assess the precision of critical screw placement in the cervical spine. The OVEM validity and reliability need to be addressed. Further correlation with clinical outcomes will be addressed in future studies.

Computed tomography-guided percutaneous trephine removal of the nidus in osteoid osteoma patients: experience of a single center in Brazil

AbstractObjective:To report the results of computed tomography (CT)-guided percutaneous resection of the nidus in 18 cases of osteoid osteoma.Materials and Methods:The medical records of 18 cases of osteoid osteoma in children, adolescents and young adults, who underwent CT-guided removal of the nidus between November, 2004 and March, 2009 were reviewed retrospectively for demographic data, lesion site, clinical outcome and complications after procedure.Results:Clinical follow-up was available for all cases at a median of 29 months (range 6–60 months). No persistence of pre-procedural pain was noted on 17 patients. Only one patient experienced recurrence of symptoms 12 months after percutaneous resection, and was successfully retreated by the same technique, resulting in a secondary success rate of 18/18 (100%).Conclusion:CT-guided removal or destruction of the nidus is a safe and effective alternative to surgical resection of the osteoid osteoma nidus.

The analgesic efficacy of ultrasound-guided transversus abdominis plane block (TAP Block) in adult patients : a meta-analysis

Introduction : Le bloc transverse de l'abdomen (bloc TAP, Transversus Abdominis Plane) échoguidé consiste en l'injection d'anesthésique local dans la paroi abdominale entre les muscles oblique interne et transverse de l'abdomen sous contrôle échographique. Ceci permet de bloquer l'innervation sensitive de la paroi antérolatérale de l'abdomen afin de soulager la douleur après des interventions chirurgicales. Auparavant, cette procédure reposait sur une technique dite « à l'aveugle » qui utilisait des repères anatomiques de surface. Depuis quelques années, cette technique est effectuée sous guidage échographique ; ainsi, il est possible de visualiser les structures anatomiques, l'aiguille et l'anesthésique local permettant ainsi une injection précise de l'anesthésique local à l'endroit désiré. Les précédentes méta- analyses sur le bloc TAP n'ont inclus qu'un nombre limité d'articles et n'ont pas examiné l'effet analgésique spécifique de la technique échoguidée. L'objectif de cette méta-analyse est donc de définir l'efficacité analgésique propre du bloc TAP échoguidé après des interventions abdominales chez une population adulte. Méthode : Cette méta-analyse a été effectuée selon les recommandations PRISMA. Une recherche a été effectuée dans les bases de donnée MEDLINE, Cochrane Central Register of Controlled Clinical Trials, Excerpta Medica database (EMBASE) et Cumulative Index to Nursing and Allied Health Literature (CINAHL). Le critère de jugement principal est la consommation intraveineuse de morphine cumulée à 6 h postopératoires, analysée selon le type de chirurgie (laparotomie, laparoscopie, césarienne), la technique anesthésique (anesthésie générale, anesthésie spinale avec/ou sans morphine intrathécale), le moment de l'injection (début ou fin de l'intervention), et la présence ou non d'une analgésie multimodale. Les critères de jugement secondaires sont, entre autres, les scores de douleur au repos et à l'effort à 6 h postopératoires (échelle analogique de 0 à 100), la présence ou non de nausées et vomissements postopératoires, la présence ou non de prurit, et le taux de complications de la technique. Résultats : Trente et une études randomisées contrôlées, incluant un total de 1611 adultes ont été incluses. Indépendamment du type de chirurgie, le bloc TAP échoguidé réduit la consommation de morphine à 6 h postopératoires (différence moyenne : 6 mg ; 95%IC : -7, -4 mg ; I =94% ; p<0.00001), sauf si les patients sont au bénéfice d'une anesthésie spinale avec morphine intrathécale. Le degré de réduction de consommation de morphine n'est pas influencé par le moment de l'injection (I2=0% ; p=0.72) ou la présence d'une analgésie multimodale (I2=73% ; p=0.05). Les scores de douleurs au repos et à l'effort à 6h postopératoire sont également réduits (différence moyenne au repos : -10 ; 95%IC : -15, -5 ; I =92% ; p=0.0002; différence moyenne en mouvement : -9 ; 95%IC : -14, -5 ; I2=58% ; p<0. 00001). Aucune différence n'a été retrouvée au niveau des nausées et vomissements postopératoires et du prurit. Deux complications mineures ont été identifiées (1 hématome, 1 réaction anaphylactoïde sur 1028 patients). Conclusions : Le bloc TAP échoguidé procure une analgésie postopératoire mineure et ne présente aucun bénéfice chez les patients ayant reçu de la morphine intrathécale. L'effet analgésique mineure est indépendant du moment de l'injection ou de la présence ou non d'une analgésie multimodale.

A concurrent region growing algorithm guided by circumscribed contours

Image segmentation of natural scenes constitutes a major problem in machine vision. This paper presents a new proposal for the image segmentation problem which has been based on the integration of edge and region information. This approach begins by detecting the main contours of the scene which are later used to guide a concurrent set of growing processes. A previous analysis of the seed pixels permits adjustment of the homogeneity criterion to the region's characteristics during the growing process. Since the high variability of regions representing outdoor scenes makes the classical homogeneity criteria useless, a new homogeneity criterion based on clustering analysis and convex hull construction is proposed. Experimental results have proven the reliability of the proposed approach

Influence of topography and surface chemistry on the wetting properties of TiO2-based ceramic coatings

Vätning av fasta ytor är ett viktigt fenomen i såväl naturen som i en lång rad av industriella tillämpningar. Det är allmänt känt att vätningen av en fast yta styrs av ytans kemi samt struktur. Målsättningen med avhandlingen var att studera hur kemisk heterogenitet och ytråhet på nanometernivå påverkar vätningsegenskaperna hos en fast yta. Ytorna som studerades var titandioxid-baserade kerama ytor som framställdes med hjälp av en sol-gel process. Vätningstudierna utfördes genom kontaktvinkelmätningar, vilket innebär att man mäter vinkeln som vätska/luft-gränsskiktet hos en vätskedroppe bildar mot en fast yta. Ytråheten hos materialen studerades främst genom atomkraftsmikroskopi (AFM). I AFM detekteras ytans struktur av en mycket skarp nål som skannar ytan. Resultaten i avhandlingen kunde framgångsrikt modelleras med existerande teorier för vätning av heterogena ytor.