Tional Techniques Research Articles

Facial Augmentation by Intra-Oral Delivery of Autologous Fat

Background As harvesting techniques have improved the viability of transposed adipose tissue, autologous fat transfer is increasingly utilized for facial augmentation. Conven- tional techniques involve placing harvested fat deep in subcutaneous tissue through skin punctures. Trans-oral fat injections at the buccal and labial sulci and through the mucosa of the oral commissures obviate external scars. We report experience with this technique for augmentation of the cheeks, zygomatic arch, nasolabial folds, upper and lower lips, and chin in 130 patients over a 14-year period. Methods We report an observational case series of 147 procedures performed in 130 patients (118 women and 12 men, 19-69 years of age) in which 10 to 60 mL autologous fat supernatant harvested from the hips, buttocks, or abdomen were injected through the oral mucosa for augmentation. Single preoperative doses of antibiotic and methyl- prednisolone were administered in all cases. Fat frozen and banked during initial treat- ments was used for additional augmentation 3 to 6 months after initial treatments in 46% of cases. Outcomes were assessed clinically with physical exams and photographs. Results Mucosal puncture wounds healed uneventfully. Most patients tolerated the procedures well and recovered rapidly compared to historical experience with conven- tional percutaneous techniques. One patient developed a sterile seroma 3 weeks after facial augmentation that responded to needle aspiration. Conclusions Transmucosal, intra-oral autologous fat grafting was associated with mini- mal visible scarring, swelling, or infection at the recipient site. This technique may be considered an alternative to percutaneous transfer for proximate peri-oral facial aug- mentation.

Body composition using bioelectrical impedance analysis in elite young soccer players: the effects of age and playing position

Most of the research in body composition of young soccer players has used anthropometric techniques as assessment methods. On the other hand, there is lack of data concerning bioelectrical impedance analysis (BIA) in young soccer players, a method which might provide more detailed information on body composition than the tradi- tional anthropometric techniques. Purpose Therefore, the aim of this study was to examine body composition assessed by BIA of young soccer players with regard to their age and playing position. Methods We examined the body composition of 65 soc- cer players (age 15.2 ± 0.2 years, weight 63.3 ± 9.4 kg, height 171.5 ± 8.3 cm and training experience of 9.0 ± 1.5 years), classified into three age groups (U14, *13 years; U16, *15 years; and U18, *17 years) and four playing positions (goalkeepers, defenders, midfielders and forwards). Results U14 showed lower weight, BMI, intracellular and extracellular water, protein, mineral mass, basal metabo- lism and all parameters of body balance (p\0.001) than U16 and U18. Within each age group, there were differ- ences between forwards and defenders (p\0.05). Also, we found differences between defenders of different age groups; defenders in the younger group had lower values in all parameters than their older counterparts and the same trend was noticed in midfielders. Conclusions Our findings with regard to positional dif- ferences in weight, height, BMI and body fat percentage were in agreement with previous studies. However, what is novel is that we observed corresponding differences in the cellular level, which should be confirmed by future studies.

Combining Multiple External Representations and Refutational Text: An Intervention on Learning to Interpret Box Plots

Box plots are frequently misinterpreted and educational attempts to correct these misinterpretations have not been successful. In this study, we used two instruc- tional techniques that seemed powerful to change the misinterpretation of the area of the box in box plots, both separately and in combination, leading to three experimental conditions, next to a control condition. First, we used multiple external representations: Histograms were used as an overlay on box plots in order to give students a better insight in the way box plots represent data distributions. Second, we used refutational text to explicitly name and invalidate the area misinterpretation of box plots. Third, we combined multiple external representations and refutational text. A box plot test showed that students in the refutation and combination condition scored statistically significant better than students in the control condition with respect to the misinterpre- tation of interest. The condition with multiple external representations scored in between. The implications of these results for theory and educational practice are discussed.

Anesthesia and Analgesia for Minimally Invasive Direct Coronary Bypass and Other "Beating Heart" Surgical Procedures

Minimally invasive direct coronary artery bypass and transmyocardial laser revascularization are examples of "beating heart" surgery which embrace new medical concepts, and the philosophy that less invasive cardiac procedures (eg, smaller incisions, avoidance of cardio pulmonary bypass) can safely achieve surgical goals. Patient and care provider expectations must be aligned with these issues if potential benefits are to be trans lated into improved patient outcome with accelerated recovery, and reduced cost for health care systems and society. There is a major role for anesthesiologists in this process, including patient and care provider educa tion, anesthetic design to appropriately involve fast- tracking principles and analgesia strategies, and the development of safe postoperative care plans outlining criteria for accelerated recovery and reduced intensive monitoring. Although enthusiasm is currently fuelling the widespread introduction of "beating heart" surgery, evidence for comparison of these procedures to tradi tional techniques is currently insufficient to confirm that they will become the established practice. Copyright© 1999 by W. B. Saunders Company.

Anatomy for ophthalmic anaesthesia

Tradi ti onal techni ques of di ssecti on fai l to show structural relationships as they exist in the living. Newer methods of cadaveric orbital fixing and thick section examination, and CT and MRI scanning techniques have added to the ease of understanding the system of connective tissue septa supporting the globe within the orbit. These tissues allow extensive mobility and also divide the orbit into functional adipose compartments allowing distribution of injected local anaesthetic solutions to gain access to neural tissue. In this review, the anatomy is described with reference to relevant drawings and diagrams and with the economical use of descriptive text. Excellent detailed texts are available for further study.

Laser-Assisted Anastomoses of the Trachea and Carotid Artery in Dogs

Anastomoses or reconstructions at the trachea are known to be related to a high risk of complications. Simi larly, anastomoses at smaller vessels have often occasioned discussion con cerning new techniques and different suturing materials. Low-dose laser energy seems to offer a new chance of tissue welding in these areas. In 10 Beagle dogs tracheal anastomoses were performed with an argon laser system, stabilized only by three single sutures for readaptation of the stumps. In 5 dogs even these three su tures were removed immediately af ter the tissue welding was finished. The anastomoses were monitored by bronchoscopy after an interval of six weeks and were removed after twelve weeks for pathologic investigations. In another 5 dogs carotid arteries were transected and reanastomosed with a similar technique. Readapta tion was achieved by four single su tures at equal distance, which were left in situ. Patency was monitored by Doppler ultrasound and by angiogra phy, and again after an interval of four to six weeks the anastomotic seg ments were resected and examined pathologically. All animals showed an uneventful postoperative course. None of the tracheal anastomoses showed any signs of functional impairment, air leakage, or infection. Bronchoscopy revealed no significant luminal nar rowing. These findings were con firmed after resection. Histology showed regular wound healing and especially normal reconstruction of the ciliated endothelium of the tra chea. Similarly all carotid anasto moses were patent in Doppler ultrasound and angiographic con trols. Neither angiography nor direct inspection after resection revealed signs of aneurysm formation. Micro scopic investigations showed a smooth endothelial passage between the two anastomosed segments and regular wound healing of the arterial wall. There were no signs of excessive scar formation or intimal hyperpla sia. The results underline the applica bility of laser energy for the perform ance of anastomoses at the tracheobronchial tree, as well as at smaller vessels. Clinical application has to be preceded by further investi gations and some technical improve ments, but still the technique shall prove to be an alternative to conven tional suturing techniques for se lected cases in the near future.

Vindaloo and you.

Correspondence and reprints to: Dr Bjarnason. Recent developments have led to the introduction of various test substances to assess intestinal permeability, some of which test the barrier function of the small intestinal mucosa.M Most of the tests are simple, comprising ingestion of a solution containing a poorly metabolised test substance and subsequent collection of urine over 5-24 hours for analysis of the test markers. Such tests have shown abnormal intestinal permeability in several gastrointestinal conditions,11 and because of their non-invasive nature they can be applied to diagnostic ^screening and research.57 Furthermore, close attention to apparent anomalies of intestinal permeability has led to the description of a new enteropathy caused by non-steroidal anti inflammatory drugs that is not evident using conven? tional techniques.810 Permeability tests have not, however, been met with universal success as diagnostic screening tests. In particular, the indigenous populations of east and west Africa,11 u the Middle East,13 Indonesia, Papua New Guinea, India, and Thailand (I S Menzies, unpublished observations) have such high perme? ability values that the tests do not discriminate between subjects with disease and normal subjects. This is in sharp contrast with the low normal values and sensitivity of the tests in whites in England,M the Continent,1419 America,2022 and Australia.23 The reasons for these differences are unknown, but as ethnic Asian (from India or Pakistan) residents in the United Kingdom24 and white residents in tropical countries mentioned (I S Menzies, unpublished obser? vations) have pronounced intestinal hyperpermeability it has been suggested that dietary factors may be important in disrupting intestinal integrity. We assessed whether ingesting three Indian meals on consecutive evenings altered intestinal function by a combined absorption and permeability test.

An Outdoor Adventure Counseling Program for Adolescents

Adolescents continue to present a dilemma for the human service system. Although the youth population has declined in recent years, the severity and frequency of need within the existing population continues to increase. Physical abuse, substance abuse, early pregnancy, suicide, poor school performance—all are growing adolescent concerns. However, tradi tional treatment techniques and settings often are inappropriate for the needs of adolescents. Although community rec reation centers are frequented by adolescents, particularly early adoles cents, traditionally structured treatment systems have difficulty reaching needy or at-risk teenagers. The gist of the problem with abused and neglected teens is a lack of trust (MacKinnon & Michels, 1971; Saund ers, 1984). Given their developmental history, it is reasonable for these teens to mistrust parental figures, to discount the ability of a parental figure to be there to help, and to dismiss the value of emotional expression in meeting per sonal needs. Outdoor adventure pro grams can help these troubled youths to gain some needed development in fun damental areas because of the natural settings where important interactions can take place.

Recent Studies of Magnetic Canopies

Two current studies are described which stem from Giovanelli's seminal studies of the spreading of chromospheric fields near active regions and active-region network. First, improved observ~tional techniques are described for obtaining magnetograms in the Ca II 8542 A, Fe I 8688 A, and C I 9111 A lines which at least in principle allow for more accurate treatment of instrumental noise and allow better inference of field .orientation. Second, a generalized response function is developed for calculating theoretical magnetograph signals from arbitrary line-of-sight variations of magnetic field, and initial applications to two-dimensional, potential-field models of network fields are described. Preliminary indications are that potential-field models can better explain the presence of low-lying, diffuse horizontal fields than can thin flux-tube models, but fail to predict a differential response between the different lines.

Item Analysis and the Measurement of Change

THE PROBLEM of item selection is complicated by the fact that each item*will change in difficulty by some unknown amount as time elapses. If no ad ditional training is given, the item will probably in crease in difficulty as forgetting proceeds. If ad ditional training is given, as is typically the case with students taking the firstsemester of a one-year introductory course, some items may conceivably decrease in difficulty. In either case, the amount of change is unknown, and, indeed, sometimes the direction of change, making it difficult to apply ra tional techniques of item selection. The measurement of retention is particularly sensitive to the difficulty of the task or item; if the task is too difficult, performance may by uniformly low, in which case, differences between groups will be masked. In laboratory experime ntal work on learning, the savings method in relearning provides the most sensitive measure of retention and has been generally adopted wherever macimal sensitiv ity is desired. Several writers (e.g., Cronbachand Warrington (1), Guilford (2), Gulliksen (3), and Lord (4) , have dealt with the relation between the ability of the group tested and the difficulty of the items to be used in constructing a sensitive test. Lord (4), for example, points out that a tes t with maximal dis criminative power for examinees at a given ability level should have all items of the same diffic ulty, such that half of the examinees at the given ability level will pass the item and half will fail it. In a test-retest study designed to measure course reten tion, we may consider that we are comparing test performance at two levels of ability: before and af ter forgetting. Therefore, knowledge of the dis criminative power of an item in the initial test pro vides no clear indication of its discriminative power in the re-test, unless the amount of forgetting (i. e., the new ability level) is known in advance. But, of course, the amount of forgetting is exactly what we are trying to find out. This problem arose during an experimental com parison of two methods of teaching general psychol ogy?a conventional course with three class meet ings per week and a self-directed study course with about one class meeting per week. It was desired to measure retention of course materials a f t er an interval of 15 months, a situation in which, unfor tunately, retention may be expected to be low and the importance of the sensitivity of the instrument looms large. Having no basis for a rational selection of items at an optimal difficulty or discrimination level, it was decided to construct the test in such a way as to provide some information for future experiments of this kind. This approach had the advantage of hedging our bets. By using items of varying but known discriminative power and difficulty in the pre-test, it appeared moderately certain that some of them would be useful in the post-test. The present report deals, therefore, with two hypotheses: 1. Items that shift in difficulty toward the opti mal level of difficulty will become more discrimin ating with the passage of time, and items that shift away from the optimal level of difficulty will become less discriminating. 2. In a situation where forgetting occurs, items that were initially much easier than the optimal dif ficulty level will shift toward the optimal level and will consequently have greater discriminative pow er in the re-test than items that were initially clos er to the optimum in difficulty. The first hypothesis is more general, but has the limitation that it cannot serve as the basis for item selection until the re-test has been administer ed. The second hypothesis requires an assumption about the direction of change in ability in the popu lation being tested, and with that restriction it can provide a guide to the selection of items for the re test on the basis of initial test results.

Rocket Boost Vehicle Mission Optimizations

A complete analysis of rocket boost trajectory optimizations is presented to illustrate some of the advantages resulting from use of the indirect methods of the calculus of variations. The method devised is intended for boost vehicle evaluations during design studies. Features of the method in­ clude provisions to account for the effects of planetary rotation, aerodynamic forces, variable at­ mosphere and time-variant thrust. Vehicle design or physiological limitations are satisfied by employing inequality constraints involving the angle of attack. Special end conditions are de­ veloped for direct calculation of extremals for most rocket boost missions of interest. Computa­ tional techniques employed to obtain solutions on a high speed digital computer are discussed, with particular emphasis on convergence of the iteration to find the desired extremal. Numerical examples are shown to illustrate the character of extremals for satellite launchings and the minimal sensitivity of extremals to guidance and control errors.