NEEDLE RENAL LIFTING TECHNIQUE IN MANAGEMENT OF COMPLICATED PROXIMAL URETERAL LITHOTRIPSY: A CASE REPORT

Objective: To described a needle renal lifting technique using an 18-gauge needle to adjunct ureterorenoscopy (URS) in the management of complicated proximal ureteral stones. Case(s) Presentation: A 46 years old man presented with right flank pain for 1 month. This patient was diagnosed with ureteral stone and ureteral kinking that prohibits access to the proximal side of the ureter. Due to difficult access to the proximal ureter, we perform a needle renal lifting technique which is initialized by puncturing the middle renal calyx with 18-gauge needle. Then, the proximal end of the needle was pushed to the caudal direction to move the kidney to the cephalic direction and straighten the kinked ureter. After that procedure, the URS sheat can easily enter the proximal ureter to the stone site. Discussion: The success rate of this procedure is based on the operator skills to access the calyx and perform URS simultaneously. Like a previous technique, needle renal lifting is effective only when the kidney is mobile. Conclusion: The needle renal lifting technique can be used to adjunct URS in the management of complicated ureteral stones which prohibited access to the proximal ureter.

Is the Greater Trochanter the Ideal Freehand Landmark for the S2AI Screw Angle in the Caudal Direction? Commentary on “Extra-articular Portion of the Sacroiliac Joint—Between the Sacral and Pelvic Tuberosities: An Anatomical Guide for the S2-Alar-Iliac Screw Trajectory” by Tatara et al

The author introduced a novel freehand technique for S2-Alar-Iliac screw placement Which demonstrated good clinical safety. However the optimal anatomical landmarks of the screw angle in the caudal direction have not been unified. The tip of the greater trochanter(TGT) was one of the most frequently chosen landmark in fluoroscopic or navigation guidance technique. Additional adjustments are always needed according to these studies. The freehand technique of the present study also choose the TGT as the as the landmark of the S2AI screw angle in the caudal direction, whether it also need any adjustment? We hope the author could explain more about this issue. Besides, the relationship between TGT and the sacral iliac bone is not static, which will make the reliability of the pre-surgery navigation software simulation doubtful.

Skin Friction Directionality in Monotonically- and Cyclically-Loaded Bio-inspired Piles in Sand

Piles can be subjected to axial loading in opposite directions during their installation and service life. For instance, piles for offshore jacket structures and load testing reaction systems are subjected to compressive loading during installation and tensile or cyclic loading during service life. This creates a design dilemma: while a large skin friction can lead to refusal at shallower depths than required during driving, it also promotes a large pile axial capacity. This paper describes the load-transfer behavior of piles with surfaces inspired by the belly scales of snakes that mobilize a direction-dependent skin friction. The investigation presented herein consists of a series of twelve centrifuge pile load tests on bio-inspired and smooth reference piles in dense and loose deposits of Ottawa F65 sand. Test results indicate that greater skin friction forces are mobilized when the bio-inspired piles are displaced in the cranial direction (i.e. soil moving against asperities) relative to the caudal direction (i.e. soil moving along asperities). This is observed during pushing and driving installation, where greater skin friction forces were mobilized during installation by pushing in the cranial direction and driving in the cranial direction required more blows per meter. Similarly, the skin friction mobilized during pullout tests was between 82% and 198% greater in the cranial direction than in the caudal direction, and the skin friction mobilized during pullout by the bio-inspired pile in the cranial direction was between 560% to 845% greater than that mobilized by the reference untextured pile. During cyclic loading, degradation of the skin friction magnitude and pile secant stiffness was observed in both cranial and caudal directions; however, the mobilized magnitudes were generally greater in the cranial direction. Discussion is provided on the potential benefits that the bio-inspired surface texture could realize on the overall performance of axially-loaded piles.

Traction force measurements on male Strepsiptera (Insecta) revealed higher forces on smooth compared with hairy substrates

ABSTRACTThe aim of this study was to find out how strongly the parasitic insect Stylopsovinae, which has tarsi equipped with tenent hairs and lacking claws, attaches to different substrates. We investigated adhesion of male S. ovinae to the abdomen of its hymenopteran host (Andrena vaga), the hairier abdomen of a Bombus sp. and two artificial smooth reference surfaces with different degrees of hydrophilicity. In our experiments, the male S. ovinae developed significantly higher forces on smooth surfaces. However, the forces were significantly lower on all the hymenopteran surfaces used in the experiment. The absence of anisotropy in the force grip in cranial/caudal direction relative to the host might indirectly indicate that S. ovinae generate forces by adhesion rather than mechanical interlocking with the host hairs. The tolerance of the attachment system of S. ovinae to the substrate chemistry might be explained by the primary contribution of van der Waals interactions and not capillary forces to adhesion in S. ovinae.

SAT-177 Relationship Between Visceral Fat and the Position of Adrenal Glands in Cranial-Caudal Direction in Patients with Primary Aldosteronism

Context: Adrenal glands locate at the retroperitoneal space and could be affected their positions by some factors. Adrenal glands being surrounded by visceral adipose tissue (VAT), we have hypothesized that the VAT amount influences the position of adrenal glands in cranial-caudal direction. In patients with primary aldosteronism (PA), comprehending the position of adrenal glands in cranial-caudal direction might be useful to predict the position of adrenal veins before performing adrenal venous sampling. Objectives: To clarify the influence of VAT amount on the position of adrenal glands, we investigated the correlation of visceral fat parameters with the position difference of adrenal glands in cranial-caudal direction in patients with PA. Materials and methods: This retrospective observational study included patients with PA according to the guidelines of both the Japan Endocrine Society and the Japan Society of Hypertension. Those with adrenal tumors more than 10 mm in diameter in computed tomography (CT) were excluded. We measured the position difference of the adrenal glands in cranial-caudal direction, from the top of right adrenal gland to the top of left adrenal gland by CT. We correlated visceral fat percentage (VF%), visceral fat area (VFA), and subcutaneous fat area (SCFA) evaluated by CT studies with the position difference of adrenal glands in cranial-caudal direction. Results: We analyzed 150 patients [male (n = 50), female (n = 100)]. Patients’ characteristics: Age was 54.8 ± 11.4, body mass index 24.9 ± 3.8 kg/m2, plasma aldosterone concentration 133.5 [101–176] pg/ml, plasma renin activity 0.3 [0.2–0.5] ng/ml/h, VF% 25.8 [19.8–33.6] %, VFA 88.3 [60.9–125.0] cm2, and SCFA was 147.4 [105.6–193.4] cm2 (mean ± SD, or median [interquartile range]). The position difference of adrenal glands in cranial-caudal direction was 9.7 ± 10.0 mm. In 120 patients (80.0%), left adrenal glands locate at the upper position comparing to right adrenal glands. In 19 patients (12.7%), right adrenal glands were positioned at the upper comparing to left adrenal glands. A positive correlation of VF%, VFA with the position difference of adrenal glands in cranial-caudal direction were shown (r = 0.451, p < 0.001, r = 0.426, p < 0.001, respectively). No significant correlation of SCFA with the position difference of adrenal glands in cranial-caudal direction was shown (r = 0.122, p = 0.139). In patients with more VAT amount, right adrenal glands locate at the upper position comparing to left adrenal glands. In patients with less VAT amount, left adrenal glands locate at the upper position comparing to right adrenal glands. Conclusions: Regardless of the variation of the position of adrenal gland on each side, the correlation was found between VAT and the position difference of adrenal glands in cranial-caudal direction in PA.

The Subcutaneous Tissue Reaction on Poly (L-lactide-co-caprolactone) based Threads

The thread-lifting procedure is gaining popularity all over the globe. It is a mini-invasive, rejuvenate procedure with a short downtime. Aesthetic practitioners use various medical devises and thread materials during thread lifting procedures, but thread degradation and tissue reaction on thread implants are currently poorly understood. Objective: This article will describe tissue reaction and thread changes from implantation to full degradation. Methods: Tissue reaction on L-lactide-co-caprolactone threads was observed on 0, 4, 13, 26, 34, 52, 64, and 72 weeks after implantation in 21 rabbit models. In all groups, except the 26-week group, eight implants were placed in each model. Specifically, four Test Articles-Aptos Excellence Visage poly (L-lactide-co-caprolactone) threads were implanted on the right side in the cranial-caudal direction, and four control articles were implanted on the left side in the cranial-caudal direction. Results: Analysis of the local tissue reaction showed that the Test Article and the control article caused the same tissue reaction. However, compared with the control article, Test Article was associated with higher numbers of inflammatory cells on 13 and 34–72 weeks. At 72 weeks, the average area of Test Article had decreased by 41.1%. Conclusion: After subcutaneous placement of the APTOS thread, the thread was progressively surrounded by fibrous tissue and exhibited slow degradation (41.1% over 72 weeks). The prolonged tissue reaction guarantees stable and durable tread-lifting procedure results. The ability of Photic tissue repositions, nucleogenesis and neovascularization has a strong influence on skin texture, structure, color and body couture which is provided by APTOS threads composition and structure.

Safe insertion of S-2 alar iliac screws: radiological comparison between 2 insertion points using computed tomography and 3D analysis software

OBJECTIVES-2 alar iliac (S2AI) screws are commonly used as anchors for lumbosacral fixation. A serious potential complication of screw insertion is major vascular injury due to anterior or caudal screw deviation. To avoid screw deviation, the pelvic inlet view on intraoperative fluoroscopy images is recommended. However, there has been no detailed investigation of optimal fluoroscopic incline with the pelvic inlet view. The purpose of this study was to investigate the safety margins and to optimize fluoroscopic settings to avoid screw deviation with 2 reported insertion techniques using 3D analysis software and CT.METHODSThe study included 50 patients (25 men and 25 women) who underwent abdominal-pelvic CT. With the use of software, the ideal S2AI screws were set from 2 entry points: A) the midpoint between the S-1 dorsal foramen and the S-2 dorsal foramen where they meet the lateral sacral crest, and B) 1 mm inferior and 1 mm lateral to the S-1 dorsal foramen. Anteriorly or caudally deviated screws were defined as deviation of a half thread of the ideal screw by rotation anteriorly or caudally from the entry point. The angular safety margins were compared between the 2 entry points, and patients with small safety margins were investigated. Subsequently, fluoroscopic images were virtualized on ray sum–rendered images. Conditions that provided proper recognition of screw deviation were investigated via lateral and anteroposterior views with the beam tilted caudally.RESULTSThe safety margins of S2AI screws were smaller in the anterior direction than in the caudal direction and by entry point A than by entry point B (A: 9.1° ± 1.6° and B: 9.7° ± 1.5° in the anterior direction; A: 10.9° ± 3.8° and B: 13.9° ± 4.1° in the caudal direction). In contrast, patients with a deep-seated L-5 vertebral body tended to have smaller safety margins in the caudal direction. All anteriorly deviated screws were recognized with a 60°–70° inlet view from the S-1 slope. The caudally deviated screws were all recognized on the lateral view, but 31% of screws at entry point A and 21% of screws at entry point B were not recognized on the pelvic inlet view.CONCLUSIONSS2AI screws should be carefully placed to avoid anterior deviation compared with caudal deviation in terms of the safety margin, except in patients with a deep-seated L-5. The difference in safety margins between entry points A and B was negligible. Intraoperative fluoroscopy is recommended with a pelvic inlet view tilted 60°–70° from the S-1 slope to avoid anterior screw deviation. The lateral view is recommended to confirm that the screw is not deviated caudally.

Realization of a multi-layer EIT-system

Electrical Impedance Tomography (EIT) is an imaging technique used for monitoring of ventilation distribution in the lung. Small alternating currents are injected and resulting voltages are measured on the body surface with electrodes fixed around the thorax. Two-dimensional EIT (2D-EIT) is the most common technique in clinical applications but enables visualization of only one horizontal slice of the thorax. However, additional information in the cranio-caudal direction is necessary to more comprehensively assess the ventilation distribution.3D-EIT systems address this issue, but clinically approved systems are not yet available. The aim of this study is to realize a multi-layer EIT-system with several electrode planes. An approved EIT system functions as basis for this development (PulmoVista 500, Dräger, Lübeck, Germany). Two planes were used for the technical realization of the multi-layer EIT-system. The alternation between the planes was realised using analog switches, which were controlled via a frequency generator and transfer the injected current and the measured voltages between the different electrode planes and the EIT device. The multi-layer EIT-System was applied to a phantom tank for first pilot measurements.Results on the phantom tank with non-conductive targets at different heights reveal that the system is capable of providing information in the cranio-caudal direction. The high frame rates of EIT images combined with the high switching speed of the used analog switches enable real-time acquisition of ventilation at different thoracic planes. Thus, the modified EIT device makes it possible to comprehensively monitor the redistribution of air in the lungs during a breathing cycle, not only in a single plane, but also in the cranio-caudal direction.