The sit-up position in breast surgery

Breast shape is best evaluated while the patient is in an upright position. However, many surgeons are reluctant to have a patient sit upright during surgery because of concerns over the patient's hemodynamic instability. Therefore, the purpose of this study was to prospectively measure cardiovascular parameters, including heart rate and mean arterial pressure, in a series of 30 patients who were placed upright during various aesthetic and reconstructive breast procedures. Data regarding the number of times the patient was placed upright and the amount of time spent in the upright position were also recorded. Measurements were obtained immediately before and after elevating the head of the bed to 80 to 90 degrees during the procedure. The average supine mean arterial pressure was 73 +/- 3 mmHg and that for an upright position was 70 +/- 3 mmHg. The average supine heart rate was 73 +/- 4 beats per minute and that for an upright position was 76 +/- 4 beats per minute. Although the difference between these results is statistically significant (p < 0.05), there was no clinical significance to placing patients in an upright seated position in this study, and no patient had to be laid back down because of hemodynamic instability. Therefore, the upright seated position is strongly advocated for intraoperative evaluation of breast shape, and a safe and effective method to accomplish this is described.     

Incision Planning in Thyroid Compartment Surgery: Getting it Perfect

ObjectiveThis study evaluated changes in thyroid compartment incision site locations with patient positioning to define a reliable method for placing the scar in the optimal vertical location.MethodsThe optimal incision location was marked with the patient sitting upright before surgery. The distance from the sternal notch to this mark was measured with the patient in the upright, supine, and final surgical positions.ResultsComplete data were available for 104 procedures. The mean distances from the sternal notch to the incision site were 4.8, 21.5, and 31.9 mm in the sitting, supine, and surgical positions, respectively. Each of these distances were significantly different from one another (P < .0001) and were independent of patient age, sex, body mass index (BMI), or height.ConclusionsCutaneous cervical landmarks migrate significantly during patient positioning. Marking the thyroid compartment incision site while the patient is in an upright position results in a more predictable final scar location. (Endocr Pract. 2015;21:107-114)     

Method for intraoperative positioning of the nipple-areola complex in vertical scar reduction mammaplasty

The desired shape and position of the nipple-areola complex may be difficult to achieve in vertical scar reduction mammaplasty when using the standard technique of preoperative marking of the so-called mosque-shaped areolar pattern of excision. We describe our modified approach of intraoperative final positioning of the nipple-areola complex by hiding the nipple-areola complex behind the closed vertical incision. Individual positioning at the final part of the operation allows for more predictable results and also for a calculated lower positioning, which enables balance of the potential bottoming-out of the breast, particularly in previously large ptotic breasts. We believe that this modification helps to further improve the results of vertical scar reduction mammaplasty by adding more possibilities for shaping and "last-minute" modifications intraoperatively.     

Improving Intra-Fractional Target Position Accuracy Using a 3D Surface Surrogate for Left Breast Irradiation Using the Respiratory-Gated Deep-Inspiration Breath-Hold Technique

Purpose

To evaluate the use of 3D optical surface imaging as a surrogate for respiratory gated deep-inspiration breath-hold (DIBH) for left breast irradiation.

Material and Methods

Patients with left-sided breast cancer treated with lumpectomy or mastectomy were selected as candidates for DIBH treatment for their external beam radiation therapy. Treatment plans were created on both free breathing (FB) and DIBH computed tomography (CT) simulation scans to determine dosimetric benefits from DIBH. The Real-time Position Management (RPM) system was used to acquire patient''s breathing trace during DIBH CT acquisition and treatment delivery. The reference 3D surface models from FB and DIBH CT scans were generated and transferred to the “AlignRT” system for patient positioning and real-time treatment monitoring. MV Cine images were acquired during treatment for each beam as quality assurance for intra-fractional position verification. The chest wall excursions measured on these images were used to define the actual target position during treatment, and to investigate the accuracy and reproducibility of RPM and AlignRT.

Results

Reduction in heart dose can be achieved using DIBH for left breast/chest wall radiation. RPM was shown to have inferior correlation with the actual target position, as determined by the MV Cine imaging. Therefore, RPM alone may not be an adequate surrogate in defining the breath-hold level. Alternatively, the AlignRT surface imaging demonstrated a superior correlation with the actual target positioning during DIBH. Both the vertical and magnitude real-time deltas (RTDs) reported by AlignRT can be used as the gating parameter, with a recommended threshold of ±3 mm and 5 mm, respectively.

Conclusion

The RPM system alone may not be sufficient for the required level of accuracy in left-sided breast/CW DIBH treatments. The 3D surface imaging can be used to ensure patient setup and monitor inter- and intra- fractional motions. Furthermore, the target position accuracy during DIBH treatment can be improved by AlignRT as a superior surrogate, in addition to the RPM system.     

Interaction between Visual and Proprioceptive Analyzers in Vertical Posture Control

The CNS can precisely assess the spatial position of the human body only by simultaneously processing and integrating the visual, proprioceptive, and vestibular inputs. Postural stability data make it possible to estimate changes taking place in the function of analyzers involved in the maintenance of the upright posture. The vertical posture stability was assessed in healthy children and children with spastic diplegic cerebral palsy from their postural responses to the presentation of single optokinetic or somatosensory stimuli. The visual analyzer was found to play a significant role in maintaining the upright position under natural gravity conditions in healthy children. A single exposure of the proprioceptive system to variable forces directed with the gravity of the earth (vertical) decreased the contribution of the visual analyzer. Healthy children maintained the upright position relying on the direction of movement of the optokinetic stimuli, which, however, produced no effect on the maintenance of posture in the patients. A hypothesis is proposed that prenatal or early postnatal CNS lesions decrease the contribution of phylogenetically newer brain structures to the regulation of upright posture.     

Breast volume and anthropomorphic measurements: normal values

Fifty-five consecutive female volunteers were evaluated. Linear measurements of the breast and nipple position were determined to fixed points on the chest wall. Volume determination was done by a standard chest-wall casting technique. A highly significant difference was found between left and right breasts in the axilla-to-nipple distance and nipple-to-midline measurements. A significant difference was also found in the distance from the lowest point of the breast (patient upright) to the nipple. Analysis of the volumetric difference between right and left breasts did not achieve statistical significance.     

Upright Imaging of Drosophila Egg Chambers

Drosophila melanogaster oogenesis provides an ideal context for studying varied developmental processes since the ovary is relatively simple in architecture, is well-characterized, and is amenable to genetic analysis. Each egg chamber consists of germ-line cells surrounded by a single epithelial layer of somatic follicle cells. Subsets of follicle cells undergo differentiation during specific stages to become several different cell types. Standard techniques primarily allow for a lateral view of egg chambers, and therefore a limited view of follicle cell organization and identity. The upright imaging protocol describes a mounting technique that enables a novel, vertical view of egg chambers with a standard confocal microscope. Samples are first mounted between two layers of glycerin jelly in a lateral (horizontal) position on a glass microscope slide. The jelly with encased egg chambers is then cut into blocks, transferred to a coverslip, and flipped to position egg chambers upright. Mounted egg chambers can be imaged on either an upright or an inverted confocal microscope. This technique enables the study of follicle cell specification, organization, molecular markers, and egg development with new detail and from a new perspective.     

Spoilage of bottled red wine by acetic acid bacteria

AIMS: To determine the bacterial species associated with an outbreak of spoilage in commercially bottled red wine where the bottles had been stored in an upright vertical compared with horizontal position. METHODS AND RESULTS: Bottled wines comprising Cabernet Sauvignon, Pinot Noir, Shiraz, Merlot and blended red varieties were examined for visible spoilage. Analysis of visibly affected and non-affected wines revealed a spectrum of aroma and flavour defects, ranging from loss of fruity aroma, staleness, oxidized character to overt volatile acidity. Only acetic acid bacteria, and not yeast or lactic acid bacteria, could be isolated from both spoiled and unspoiled wines and were found to grow only on Wallerstein Nutrient (WL) medium supplemented with 10% red wine or 1-2% ethanol. Analysis of the 16S rRNA region and RAPD-PCR analysis showed the isolates to be a closely related group of Acetobacter pasteurianus, but this group was differentiated from the group comprising beer, vinegar and cider strains. CONCLUSIONS: A. pasteurianus was the species considered responsible for the spoilage but the isolates obtained had atypical properties for this species. In particular, they failed to grow on WL nutrient medium without ethanol or wine supplementation. Storage of the bottles of wine containing A. pasteurianus in an upright vertical position specifically induced growth and spoilage in a proportion of the bottles under conditions that were inhibitory for horizontally stored bottles. We hypothesize that the upright position created a heterogeneous environment that allowed the growth of bacteria in only those bottles sealed with cork closures that had upper limit for the natural permeability to oxygen. Such a heterogeneous environment would not exist in horizontally stored bottles as the larger volume of wine adjacent to the cork would strongly compete with the bacteria for the oxygen as it diffuses through the cork closure. SIGNIFICANCE AND IMPACT OF THE STUDY: A low level of bacteria (acetic acid bacteria) in wine can proliferate and cause wine spoilage in bottles stored in an upright vertical as opposed to an horizontal position under conditions that would normally limit bacterial development.     

Immediate breast reconstruction with deepithelialized TRAM flaps: techniques for improving breast reconstruction

In selected patients with lower quadrant breast masses, large breasts, and sufficient abdominal tissue, standard techniques for breast reconstruction can be modified to improve overall results. The transverse abdominal island flap can be deepithelialized and mobilized to reconstruct unilateral or bilateral defects. Furthermore, skin markings prior to mastectomy that conform to a modified Wise pattern will allow for more aesthetic positioning of eventual scars. We present a case report of a patient who underwent immediate breast reconstruction with bilateral deepithelialized lower rectus abdominis myodermal flaps.     

Scintigraphie de perfusion cérébrale positionnelle : résultats physiologiques et applications cliniques

To assess the impact of standing on brain perfusion, 125 brain perfusion scans in the upright and supine position were performed, including 108 patients. Perfusion values were compared using a relative quantitative approach and a segmentation of vascular territories with the help of an atlas of brain perfusion. We found a change in the distribution of the perfusion in favor of the vertebro-basilar system in the upright position. We discuss the case of a patient whose symptoms could be explained with the help of the comparison of brain perfusion scans in the upright and supine position. Atheromatous and post-dissection stenosis and their influence on perfusion are also discussed.     

Biomechanics, evolution and upright stature

The transition from a basically quadrupedal to an upright stance must have been a critical stage in the early hominids before the appearance of Australopithecus and after a Ramaor Dryopithecine time. Two hypotheses have been postulated as to how the change occurred: 1. a gradualistic evolution from the horizontal to a more and more vertical body posture; and 2. an "either--or" position, in which our early ancestor assumed either a horizontal or a vertical posture. It is calculated that, in a static equilibrium, a semi-erect posture would be disadvantageous from the point of view of muscle forces as well as from energetic constraints. These stresses make it probable that an upright posture and carrying of objects in the hands were jointly favored by natural selection and that an intermediate stage would be short and inconclusive. The postural change would thus have occurred in a "punctuated equilibrium" manner of evolution.     

Static block jump techniques in volleyball: upright versus squat starting positions

The difference in maximal jump height between static block jump starting from an upright position (upright BJ) and static block jump starting from a squat position (squat BJ) was determined in 10 division II collegiate women volleyball players. Also determined was the difference in take off time for quick block jump, to a constant point above the net, between upright BJs and squat BJs. An AMTI force plate and a video camera (60 Hz) were used to collect the data. Each subject performed three maximal upright BJs and three maximal squat BJs, and five quick upright BJs and five quick squat BJs, randomly. The highest jump for maximal upright BJs and squat BJs, and the fastest jump for quick upright BJs and squat BJs were recorded. There was a significant difference (p < 0.03) between maximal upright BJs and squat BJs in height jump; maximal upright BJ (33.2 cm) was higher by 1.2 cm. No significant difference (p > 0.5) was found for the fastest take off time (approximately 0.7 s) between quick upright BJs and squat BJs. These results suggest that college women volleyball players can jump higher from the upright, compared with the squat, position. They can take off to the same block position equally quickly from either the upright or squat starting position. These data may suggest that conditioning coaches should identify their players' preferred BJ position and incorporate a specific training program to enhance the players' power. Furthermore, the coaches may need to incorporate more specific squat endurance exercises.     

Biomechanical model study of pelvic belt influence on muscle and ligament forces

Many patients with low back and/or pelvic girdle pain feel relief after application of a pelvic belt. External compression might unload painful ligaments and joints, but the exact mechanical effect on pelvic structures, especially in (active) upright position, is still unknown. In the present study, a static three-dimensional (3-D) pelvic model was used to simulate compression at the level of anterior superior iliac spine and the greater trochanter. The model optimised forces in 100 muscles, 8 ligaments and 8 joints in upright trunk, pelvis and upper legs using a criterion of minimising maximum muscle stress. Initially, abdominal muscles, sacrotuberal ligaments and vertical sacroiliac joints (SIJ) shear forces mainly balanced a trunk weight of 500N in upright position. Application of 50N medial compression force at the anterior superior iliac spine (equivalent to 25N belt tension force) deactivated some dorsal hip muscles and reduced the maximum muscle stress by 37%. Increasing the compression up to 100N reduced the vertical SIJ shear force by 10% and increased SIJ compression force with 52%. Shifting the medial compression force of 100N in steps of 10N to the greater trochanter did not change the muscle activation pattern but further increased SIJ compression force by 40% compared to coxal compression. Moreover, the passive ligament forces were distributed over the sacrotuberal, the sacrospinal and the posterior ligaments. The findings support the cause-related designing of new pelvic belts to unload painful pelvic ligaments or muscles in upright posture.     

Effect of tongue position on postural stability during quiet standing in healthy young males

Abstract

Background and aims: Role of the neck and jaw sensory motor system in control of body balance has been established. Tongue is an integral part of jaw sensory motor system and helps in execution of purposeful and precise motor tasks like eating, drinking and speaking. The purpose of this study was to evaluate the possible effects of tongue position on the postural control system.

Materials and method: We compared the mean center of gravity (COG) velocity during quiet standing on an unstable surface with eyes closed during two test conditions: (i) with habitual jaw resting position and (ii) with instructed tongue positioned against the upper incisors. One hundred and sixteen normal healthy male subjects (average age 31.56?±?8.51 years and height 170.86?±?7.26?cm) participated in the study. Their COG velocity (deg/s) was measured using the NeuroCom® Balance Master version 8.5.0 (Clackamas, OR, USA).

Results and conclusions: The results show that COG velocity decreased significantly while tongue was positioned against upper incisors in comparison to the habitual jaw resting position. Our findings suggest that the tongue positioning can modulate postural control mechanisms. Tongue positioning against the upper incisors can enhance the postural stability during upright standing on an unstable surface and in the absence of vision in healthy young adults. Our findings can be of value for evaluation and rehabilitation protocols for postural control dysfunction.     

The Influence of Postural Changes on the Glomerular Filtration Rate in Nephroptosis

The influence of postural changes on renal function was determined in 13 patients with nephroptosis and in 5 normal subjects by measuring GFR in the erect and supine positions. The results indicate that GFR was reduced in the erect position in 10 of 13 patients with either unilateral or bilateral nephroptosis whereas GFR was increased in the erect position in 4 of 5 patients without renal disease. One patient with bilateral nephroptosis and renovascular hypertension was studied before and after surgical correction of his disease. These observations indicate that patients with nephroptosis may have significant reductions in renal function when they assume an upright position, and suggest that GFR measurements in the supine and erect position in patients with nephroptosis can be helpful in evaluating this disease.     

Development and validation of a computational model for understanding the effects of an upright birthing position on the female pelvis

Upright, natural birthing positions, such as squatting, are associated with several clinical benefits, yet recumbent positions are still most common during delivery in most health centres. The biomechanics of birth positioning are not yet fully understood; therefore, our objectives were to develop and validate a computational model that could determine pelvic kinematics under loading conditions resulting from an upright birthing position. A three-dimensional model of the pelvic region was created from MRI scans of a non-pregnant subject. Bones were designated rigid segments with sacroiliac and pubic symphysis joint motion constrained only by contact surfaces and ligaments modeled as non-linear spring elements. Actuating torques at the lumbosacral and hip joints were defined based on motion analyses of squatting. The model was validated by comparing simulation results with data from the literature and in vivo MRI data from three subjects in a kneel-squat position. Good agreement was found between clinical pelvimetry measurements from the squat simulation and MRI data. Differences between simulation predictions were within one standard deviation of mean MRI kneel-squat results for all clinical measurements except one: the predicted increase in bispinous diameter was approximately 1.5 standard deviations less than that of the mean MRI results and still well within physiologic limits according to data in the literature. This model can, therefore, be used to provide further insight into the biomechanics of certain upright birthing positions, such as squatting.     

Improving safety and aesthetic results in inverted T scar breast reduction

Breast reduction using an inverted T scar skin design and a variety of glandular pedicle types is widely practiced and is the standard by which more recent limited scar techniques are judged. The inverted T procedures are attractive because they are predictable and versatile and permit great control over both the extent of reduction and the breast-shaping process. Despite these advantages, common criticisms of inverted T scar techniques include breast shape abnormalities, areolar malposition, hypertrophic scars, and poor long-term projection. Preoperative markings influence both safety and aesthetics. A method of skin marking that is based on a displacement method to determine vertical limb splay angle is described. This design concept must be modified to address certain variants, such as macromastia presenting with normal nipple position or large-diameter areolae, moderately severe macromastia, and macromastia involving radiated breasts. Safety in breast reduction is improved by paying attention to patient positioning issues, using techniques that minimize blood loss, raising flaps of appropriate thickness in the correct plane, and performing resection by observing the principles that reduce the risk of compromise of nipple and areolar circulation. Aesthetic results are improved by analyzing vertical breast meridian lengths during final breast shaping, modifying areolar shape as necessary, and carefully tailoring the medial inframammary crease. The latter is also important for minimizing the potential for scar hypertrophy. The principles presented have been refined during the course of a 12-year experience with several hundred breast reduction procedures. They contribute to improved results in inverted T scar breast reduction when practiced consistently.     

Internal reference frame for the representation and storage of visual information during standing

The roles of different afferent systems in the organization of an internal reference frame was studied. The task of visual comparison was performed by subjects under different experimental conditions: in the upright standing position and with the body or head inclined in the frontal plane and with the visual information about an external environment available or not available. It was shown that the dominant orientation of a referent stimulus (the minimum value of the mean error in the reproduction of the stimulus and the minimal variability of the error) was correlated with the body position, mainly the position of the head, more than with the gravitational or visual vertical, even when the visual information was available. This means that the proprioceptive information about the longitudinal axis of body, rather than gravity, is mainly used by the central nervous system for creating the internal representing of vertical during standing.     

The spontaneous growth response of maize coleoptile segments and the change in tissue 8

Decapitated segments from maize (Zea mays L.) coleoptiles orientedvertically in an upright position show a strong spontaneousgrowth response (SGR) 3 h after decapitation. The latent periodof the SGR is markedly reduced when these segments are orientedin an inverted position. Coleoptile segments with intact tipsexhibit a weak and transient SGR in the vertical upright orientation.However, in the inverted orientation, these segments show atypical SGR. The data are inconsistent with the current hypothesisthat the SGR is caused by a time-dependent increase in tissuesensitivity to auxin. The parallel increase in membrane potentialdifference and growth rate during the time-course of the SGRindicates a possible role for PM H⁺-ATPase in the establishmentof the SGR in maize coleoptile segments. Key words: Auxin, spontaneous growth response, membrane potential, plasma membrane H⁺-ATPase, Zea mays L.