Needle Point Research Articles

Bakterielle Kontamination von Injektionskanülen nach intravitrealer operativer Medikamenteneingabe in Paraguay

The study was designed to prospectively evaluate the bacterial contamination of needles used for intravitreal injection during surgery. Between December 2007 and December 2010, 549 eyes of 413 patients were treated with intravitreal injections of 1.25mg bevacizumab. Of the patients 322 received a single injection and 91 multiple injections. Preoperatively the periorbital skin of all patients was treated with 10% povidone iodine (PVI) and the conjunctival sac was irrigated with 1% PVI. No pre-injection antibiotics were administered. Immediately after the injection the needles were rinsed 3 times in thioglycolate broth which was then cultured at 37°C for 5 days. As a negative control 73 sterile unused needles were treated in the same way. Out of the 549 needle points tested 8 (1,45%) were found to be contaminated after intravitreal injections. The isolated bacteria were coagulase negative Staphylococcus (n = 7), Propionibacterium acnes (n = 1) and Klebsiella pneumoniae (n = 1) (co-contamination in one case). Contamination of needles is minimal after prophylactic povidone iodine irrigation before intravitreal injections. Therefore, this prophylaxis technique is recommended before intravitreal injections in order to prevent postoperative infections.

Investigation of the vibrational temperature and gas temperature in gas discharge generated by plasma needle

Low temperature plasma generated by plasma needle in atmospheric pressure air has extensive application prospects in industry because the vacuum device can be dispensable. In the present paper a stable plasma plume was generated in air by using a plasma needle device. The vibrational temperature and gas temperature were investigated for the plasma plume by optical spectroscopic method. Research results show that the plasma plume generated in atmospheric pressure air can be distinguished as a strong emission area near the needle followed by a weak emission area. The light emission signal from the discharge is a pulse per half cycle of the applied voltage with a time width of several microseconds. Results also indicate that the vabrational temperature varies from 2 500 to 3 000 K for different emission locations. The vibrational temperature increases with increasing the distance from the needle point in the strong emission area and it reaches a peak value at a distance of about 5mm from the needle point. The vibrational temperature decreases with increasing the distance from the needle. Similarly, the gas temperature decreases from 640K to 540K with increasing the distance from the needle point. These results are of great importance for the industrial applications of air discharge at atmospheric pressure.

Comparative Evaluation of the Effects of Electrohydrodynamic, Oven, and Ambient Air on Carrot Cylindrical Slices during Drying Process

Electrohydrodynamic (EHD) drying is a novel method of nonthermal drying. A corona discharge using multiple electrodes and a high-voltage electric field of 5.2 kV · cm−1 was produced to investigate the drying enhancement of carrot slices and its effect on color and shrinkage. The EHD setup consisted of 13 stainless steel needle points connected to a DC power supply and a stainless steel plate. EHD+ drying, EHD− drying, oven drying at 55°C, and ambient air drying control at 25°C for 5 h resulted in 79.5, 77.7, 77, and 22.5% total moisture removal from the fresh carrot slices, respectively. The final shrinkage of the EHD± drying was less than that of oven drying but was higher than that of ambient air drying. It was estimated that the energy consumption of oven drying was several times greater than those of EHD± drying. The conventional drying processes changed all color parameters, whereas the color for EHD± dried samples remained almost the same. The carrot slices’ temperature during drying by EHD± was significantly less than that of those dried by oven and ambient air drying.

SU-E-T-592: A Novel 3D CT-Based Treatment Planning for Palladium 103 Breast Seed Implant Brachytherapy

Purpose: To present a novel 3D CT-based treatment planning method for permanent breast seed implant (PBSI) with Palladium-103. Methods: On a pilot study for adjuvant partial breast irradiation between 2003 and 2005 at the BC Cancer Agency, Vancouver Island, Canada, we established a unique method for planning CT-based multi-catheter HDR interstitial brachytherapy using Varian BrachyVision. Based on our experience from that study we transferred the concept to LDR Palladium-103 PBSI. Patients are CT scanned with two radio-opaque grids placed on the medial and lateral aspect of the breast and other reference skin markers are added. The grids assist in determining the entrance and exit point of a reference needle. The implant is then guided by landmark measurements and the reference needle. Results: We found that the BrachyVision system, developed by Varian for planning of LDR seed implants, was unsuitable for needle-based preplanning. When we used the afterloader planning tools, we were able to adapt its parameters to represent manual needle loadings. The total dose was converted to dose rate because of the lack of flexibility for permanent implant prescription. The BrachyVision afterloader interstitial planning tools were suitable for producing an optimal plan for PBSI with Palladium- 103 in a relatively short time. Images in the oblique plane were generated in BrachyVision and exported to VariSeed planning system for validation. An image manipulation software was used to overlay images for BrachyVision and VariSeed for comparison. The dose distribution variance between the two systems was found to be within 3%. Conclusions: The BrachyVison afterloader planning concept can be used for PBSI planning. An optimal plan can be obtained in a relatively short time with minimal planner intervention. The skin grid guidance may achieve high accuracy of seed placements without the aid of a real time ultrasound.

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Cryopreservation of mouse testicular tissue: prospect for harvesting spermatogonial stem cells for fertility preservation

To investigate the efficacy of vitrification, rapid freezing, and slow freezing in preserving testicular tissue for subsequent isolation of spermatogonial stem cells. Experimental study. University-based laboratory. Immature mouse testicular tissue. The tunica of the testis was manipulated before cryopreservation. The tunica was either breached with a fine needle or completely removed, or the testis was sectioned longitudinally into halves. Cell viability by Trypan blue exclusion test and flow cytometry analysis of live-dead cytotoxicity test, measurement of hormonal production, enrichment of spermatogonial stem cells with use of magnetic-activated cell sorting technology. Samples with tunica minimally penetrated with a needle point gave the highest cell viability after freezing and thawing. Vitrification protocol with use of an ethylene glycol-sucrose-based vitrification solution (40% vol/vol ethylene glycol-0.6 mol/L sucrose) was able to maintain postwarming cell viability and functions similar to those of noncryopreserved controls and significantly better than both conventional slow and rapid freezing protocols. Primitive spermatogonial stem cells were enriched successfully from vitrified tissue via magnetic-activated cell sorting. Vitrification of testicular tissue is a time- and cost-efficient strategy to preserve spermatogonial stem cells for potential transplantation procedure.

Impulse breakdown of small air gap in electric field Part I: Influence of barrier position

The influence of barrier position on breakdown voltage in air dielectric has been investigated. Needle and Cone positive point electrodes were used and the effects of electrode curvature on barrier position for maximum breakdown voltage were compared, with air gap for the point to plane electrode fixed at 10 cm for all the tests. The breakdown probability was found for barrier position, and at every barrier distance, the breakdown voltage differed. The position for maximum breakdown for needle electrode was in the range of 28 - 30 % from the poi-nt electrode. The position for optimum breakdown for cone electrode was 50 % from the point electrode, and the deviation originated from the electrode configuration. The effect of defective barrier was tested by introducing holes of different diameter at the barrier centre, and the maximum breakdown voltage was affected depending upon the diameter of the hole on the barrier.

The effect of needle size inducing degeneration in the rat caudal disc: evaluation using radiograph, magnetic resonance imaging, histology, and immunohistochemistry

Background context The rat caudal disc has been increasingly used in studying of disc degeneration because of its simplicity, low cost, and efficiency. However, the reproducibility and standardization are essential to facilitate the investigations of biologic therapeutics at different stages of degeneration. Purpose To identify the effect of different needle gauges to the degenerative response in rat caudal discs and to examine its pathogenesis by looking at the cellular and matrix changes. Study design In vivo study of injury-induced rat caudal disc degeneration using needle puncture. Patient sample Thirty-six Lewis rats aged 12–14 weeks. Outcome measures The induced degenerative discs were analyzed by plain radiograph, magnetic resonance imaging (MRI) and histological examination. Proteoglycan content was assessed by alcian blue stain. Immunohistochemistry using aggrecan, collagen II, and Sox-9 was also evaluated to investigate cell differentiation and matrix changes. Methods All rats were divided into three groups according to different needle gauges (18G, 20G, and 22G). Caudal discs were punctured percutaneously under image guidance. Radiographs and MRI were obtained at 2 weeks interval until 8 weeks. At each time point, three rats from each group were sacrificed for histological analysis and immunohistochemistry. Results Larger needle gauges, especially 18G, produced more deterioration of the disc when compared with smaller sizes, particularly with time. Significant differences were identified in almost all parameters compared between 18G and 22G at the 8-week time point. For the effect of time in the same needle size, the differences occurred between 2- or 4-week and 8-week time point in the 18G and 20G groups. The proteoglycan and aggrecan stain gradually decreased over time. Chondrogenic differentiation was identified within the degenerative disc by detecting Sox-9 positive cells and collagen II accumulation increased as degeneration progressed. Conclusions The puncture-induced degenerative changes in rat caudal discs can imitate the human degenerative cascade as observed in plain radiograph, MRI, histology, and immunohistochemistry. We suggest that needle size affects the occurrence of progression of degeneration; thus, the large needle size was required to accelerate the deterioration. The size of needle and time point after injury should be considered when investigating the effect of therapeutic materials to retard degeneration or regenerate the intervertebral disc.

DESCRIPTION OF A SIMPLE METHOD FOR IN VIVO FOLLICULAR OOCYTE RECOVERY IN THE RABBIT

A simple and inexpensive folliculocentesis set was developed for in vivo recovery of rabbit follicular oocytes. The work focused on evaluating recovery rates and procedure sequels. The folliculocentesis set was composed of two concentric catheters. Briefly, the procedure involves inserting the needle point, attached to the inner catheter, into the follicular cavity; flushing the perfusion medium at the same time, in order to wash the follicular contents. 14 does were used in this experiment. Folliculocentesis was performed 7-9 hours alter hCG-treatment (25 IU). The maximum diameter of the intact follicles to be punctured was 1.5 mm. The average operating time was around 14 minutes per doe. Overall, per doe, an average of 10.14 follicles were punctured and 7.0 oocytes were recovered (recovery rate 69%). Does were slaughtered 48 hours after follicular puncture and no sequels were detected at the ovarian level.

An Maximization of Ionic Wind Utilizing a Cylindrical Corona Electrode

A corona discharge system with needle point or wire type corona electrode has been well used as an ionic wind blower. The corona discharge system with a needle point electrode produces ions at lower applied voltage effectively. However, the corona discharge on the needle point electrode transits to the arc discharge at lower voltage, and it is hard to obtain the elevated electric field in the discharge airgap for enhancing the ion migration velocity due to the weak Coulomb force. A cylindrical corona electrode with sharp round tip is reported as one of effective corona electrode, because of its higher breakdown voltage than that of the needle electrode. A basic study, for the effectiveness of cylindrical electrode shape on the ionic wind generation, has been investigated to obtain an maximum wind velocity, which however is the final goal for the real field application of this kind ionic wind blower. In this paper, a parametric study for maximizing the ionic wind velocity utilizing the cylindrical corona electrode and a maximum ion wind velocity of 4.1 m/s were obtained, which is about 1.8 times higher than that of 2.3m/s obtained with the needle corona electrode from the velocity profile.

Effect of Radius of Curvature of a Corona Needle on Ionic Wind Generation

An electric fan for cooling high density electronic devices is limited and operated in very low efficiency. The corona discharge is utilized as the driving mechanism for an ionic gas pump, which allows for air flow control and generation with low noise and no moving parts. These ideal characteristics of ionic pump give rise to variety applications. However, all of these applications would benefit from maximizing the flow velocities and yields of the ionic pump. In this study, a needle-mesh type ionic pump has been investigated by focusing on the radius of curvature of corona needle points elevating the ionic wind velocity and efficiency. It is found that the radius of curvature of the corona discharge needle point influences significantly to produce the ionic wind and efficiency. As a result, an elevated ionic wind velocity and increased ionic wind generation yield can be obtained by optimized the radius of curvature of the corona needle electrode.

Influence of suture regularity on corneal astigmatism after penetrating keratoplasty

To investigate whether suture regularity affects corneal astigmatism after keratoplasty. Twenty-one patients undergoing penetrating keratoplasty for various corneal diseases were included in the study. The grafts were sutured in place using a single-running Nylon 10-0 suture, taking 24 bites. Immediately after surgery, standard calibrated images of the grafted eye were captured and stored. Using a dedicated image analysis programme, stitches and needle points were identified, and a number of suture regularity variables were calculated. Corneal topographic images were obtained before suture removal (12 months after surgery) and 3 months after suture removal (18 months after surgery). Topographic measures of astigmatism [surface regularity (SRI), surface asymmetry index (SAI) and simulated keratometric astigmatism] were calculated and correlated with the computed suture regularity variables. The average stitch length was 3.04 ± 0.28 mm and the distance between the outer needle points was 2.53 ± 0.09 mm. The SRI was 1.26 ± 0.36 and the SAI was 1.59 ± 0.67 after 12 months; these decreased to 1.03 ± 0.48 and 0.92 ± 0.46 after 18 months, respectively. Corneal astigmatism was 6.38 ± 2.99 and 5.87 ± 3.13 dioptres after 12 and 18 months, respectively. Suture regularity did not affect SAI, SRI or corneal astigmatism significantly 12 months after surgery. Eighteen months after surgery (3 months after suture removal), the standard deviation on the original stitch length was found to significantly increase corneal astigmatism. In addition, the size of the counter-clockwise angle between stitch and graft radian was correlated significantly with a lower SRI. The origin of corneal astigmatism after penetrating keratoplasty is multifaceted. Regular stitch length and stitch advancement on the surface appears to improve the optical quality of the graft after suture removal. Factors such as stitch depth, suture tension and variations in wound construction might also be important predictors of corneal astigmatism after penetrating keratoplasty.

Histologic assessment of thermal injury to tonsillectomy specimens: A comparison of electrocautery, coblation, harmonic scalpel, and tonsillotome

To determine the extent of thermal injury to the tonsillar tissue following the use of various types of instrumentation. To determine if tonsillectomy specimens routinely contain tissue other than lymphoid tissue. Retrospective histologic analysis. A histologic analysis performed on 228 tonsillectomy specimens removed by use of an electrocautery in 132 specimens, harmonic scalpel in 46, coblation device in 24, and a tonsillotome in 26. The specimens were evaluated for presence and percentage of skeletal muscle and depth of thermal tissue injury. The mean percentage of skeletal muscle present in the specimens was 0.79% for electrocautery, 1.74% for harmonic scalpel, 0.97% for coblation device, and 1.66% for the tonsillotome. Skeletal muscle was absent in only 8 of 228 specimens (3.5%). Electrocautery has a statistically significant (P < .05) lower percentage of muscle tissue compared to harmonic scalpel and the tonsillotome. There was no statistically significant difference in the mean depth of thermal injury among the harmonic scalpel (0.68 mm), electrocautery (0.58 mm), and coblation device (0.71 mm) specimens. The tonsillotome specimens had no thermal injury. Attempts to remove the entire tonsil results in a similar depth of thermal injury to tonsillectomy specimens when using the harmonic scalpel, electrocautery, and coblation device. Skeletal muscle is a nearly ubiquitous finding in routine tonsillectomy specimens. The use of an electrocautery with a needle point may allow for a more precise dissection as it results in tonsillectomy specimens with a smaller percentage of muscle present.

Bacterial Contamination of Needle Points after Intravitreal Injection

Evaluation of the magnitude and pattern of bacterial contamination of needle points with conjunctival bacteria during the intravitreal injection. Analysis of the efficacy of preinjection prophylaxis. A total of 550 intravitreal injections were done in 414 patients (n=425 eyes). A total of 289 patients were injected once, while 125 patients received several injections. Before the intravitreal injection in the operation room, the following standard preoperative preparation of the eye-10% povidone iodine scrub on the eyelids, eyelashes, and forehead and irrigation of the conjunctival sac with 1% povidone iodine-was carried out. Immediately after the injection, the needle points were rinsed three times in thioglycolate broth, which was cultured at 35 degrees C for 5 days afterwards. As a negative control, 200 sterile unused needle points were treated the same way. Only 2 out of 550 (0.36%) needle points were contaminated after intravitreal injection. In sensitivity testing, the isolated Staphylococcus epidermidis and Corynebacterium sp did not show multidrug resistance. All 200 unused needle points proved to be sterile after 5 days of cultivation. Contamination of needle points is minimal after iodine irrigation prophylaxis before intravitreal injection. Therefore, we recommend this prophylaxis technique before intravitreal injections. The low incidence of contaminated needle points, however, shows that there still is a risk of bacteria entering into the eye during injection.

Experimental study of the effect of wind on positive and negative corona from a sharp point in a thunderstorm

Corona discharge measurements made during a thunderstorm on a mountain at an altitude of almost 3300 m above sea level were analyzed for their dependence on the ambient electric field and the local wind speed. The corona current data were taken from an earthed needle point mounted at a height of 3 m above the ground. The coronating point was exposed to natural wind speeds of up to 14 m/s. Comparisons are made with empirical relationships dating back to the mid-1900s and new formulae are provided to describe the effect of wind on the magnitude of corona current measured under natural conditions.

MONOPOLAR DIATHERMY DISSECTION MADE EASY

Monopolar diathermy is employed widely in surgery, but detailed examination of its use reveals that the full potential of the instrument as a dissecting tool is not always realised. Two factors compromise its use for accurate dissection: 1) the location and control of the hand control buttons; and 2) use of a needle point. This review demonstrates how the foot control (by allowing the instrument to be held closer to the tissues) and the round-tipped spatula end (by allowing blunt dissection without having to change instruments) can markedly increase the precision and efficiency of operative dissection.

Poster 266: The Effect of Needle Position and Contrast Spread Pattern on Outcome of Lumbar Transforaminal Epidural Steroid Injections

Objective: To determine if medication delivery into epidural space confirmed by contrast enhancement fluoroscopic images is superior to a neurogram placement; to determine if lumbar transforaminal epidural steroid injections needle position can effect contrast spread pattern and outcome. Design: Prospective, evaluator-blind clinical trial. Setting: Outpatient multidisciplinary spine care center. Participants: 50 patients with L4 and/or L5 radiculopathy who failed conservative management. Interventions: L4-L5 and/or L5-S1 lumbar transforaminal epidural steroid injections. Main Outcome Measures: A survey that included Verbal Rating Scale (VRS), visual analog scale (VAS), Oswestry Disability Index (ODI), Hospital Anxiety and Depression Scale (HADS), and Pain Catastrophizing Scale (PCS). Fluoroscopic radiographs reviewed by a radiologist blinded to the patient and outcome to identify needle position (AP/lateral views) and contrast flow. With the AP view, the radiologist determined the needle point to be at medial or lateral by using the 6 o'clock position as midline. In the lateral view, the location of the needle tip was classified as 12 o'clock, 3 o'clock, 6 o'clock, or 9 o'clock position. Results: 68% of patients were women and 32% were men, with average age ± SD of 56.7±14.9 years (range, 19–86y). At the L4-L5 level, 58% were neurograms, 0% epidural only, and 26% with both patterns. At the L5-S1 level, 48% were neurograms, 6% epidural, and 44% had both patterns. There were no statistically significant differences between needle position and functional outcome using the VRS, VAS, and ODI. There appeared to be a trend for better outcome as measured by change in VRS, VAS, HADS, and ODI for epidural contrast pattern. Interestingly, there was a trend for worse PCS scores in the epidural group when compared with the neurogram-only group. Conclusions: These findings suggest that there is no benefit in functional outcome as related to needle position within the foramina. It is likely that regardless of needle position, epidural spread of the medication is the more important factor in functional improvement with lumbar transforaminal epidural steroid injections. Limitations include small sample size and possible overlapping effect with multi-level injections. Further studies with larger sample size are needed to address outcome improvement in correlation with fluoroscopic images.

Surgical pearl: a simple means of disarming the “locked and loaded” needle

Surgery, in any setting, has several inherent risks not only to the patient, but the physician and his assistants as well. Safe handling and management of the sharps to prevent inoculation injuries is one of these risks, in particular: 1) instrument hand-off of the needle and needle driver between the physician and his assistants; 2) retrieval of instruments from the surgical tray. The authors' review a simple means of disarming the needle loaded in the needle driver to reduce sharps injury. Before the needle and needle driver are either handed off to the assistant or returned to the surgical tray, pivot the needle 90 degrees toward the instrument joint. The needle's point should be directed toward and touching the needle driver, and thereby, disarming the needle. To avoid dulling the needle, the point should not be grasped by the needle driver. Disarming the loaded needle may reduce the chance of sharps injury during instrument hand off and retrieving instruments from the surgical tray.

Application of a new method of needles withdrawal in elderly patients

Objective To observe the haemostatic effects of rising-arm after needle withdrawal to the elderly. Methods 45 consecutive patients were enrolled in our study, with mean age 86.5 years old and 82.2% of them being accepted anti-platelet therapy. Total of 900 times routine intravenous were adopted. Two hematostatic methods were used: traditional pressure method and rising-arm method. The differences of the two methods were observed by using one method in the single days and the other in the double davs with selfcontrolled way. Results There are no statistical differences in hematostatic effect between the two methods (97.6% versus 96.3%. P=0.337). Contrast to traditional pressure method, the rising-arm method had high satisfaction rate for nurse. The bleed can be prevented by giving some degree of pressure to the needle point at the same time of rising arm. Conclusions Rising-arm method is a good hematostatic method, especially for elderly patients being accepted anti-platelet therapy. Key words: Needle withdrawal; Rising-arm; The elderly

Two Modes of Acupuncture as a Treatment for Hot Flushes in Men with Prostate Cancer—A Prospective Multicenter Study with Long-Term Follow-Up

BackgroundHot flushes are common and distressing among men with castrational treatment for prostate cancer. Of the few treatments, most have side effects. ObjectiveAssess changes in hot flushes of electrostimulated (EA) and traditional acupuncture (TA). Design, Setting, and ParticipantsThirty-one men with hot flushes due to prostate cancer treatment were recruited from three urological departments in Sweden, from 2001 to 2004. InterventionThirty-one men were randomized to EA (12 needle points, with 4 electrostimulated) or TA (12 needle points) weekly for 12 wk. MeasurementsPrimary outcome: number of and distress from hot flushes in 24h and change in “hot flush score.” Secondary outcome: change in 24-h urine excretion of CGRP (calcitonin gene–related peptide). Results and LimitationsTwenty-nine men completed the treatment. Hot flushes per 24h decreased significantly, from a median of 7.6 (interquartile range [IQR], 6.0–12.3) at baseline in the EA group to 4.1 (IQR, 2.0–6.5) (p=0.012) after 12 wk, and from 5.7 (IQR, 5.1–9.5) in the TA group to 3.4 (IQR1.8–6.3) (p=0.001). Distress by flushes decreased from 8.2 (IQR, 6.5–10.7) in the EA group to 3.3 (IQR, 0.3–8.1) (p=0.003), and from 7.6 (IQR, 4.7–8.3) to 3.4 (IQR, 2.0–5.6) (p=0.001) in the TA group after 12 wk, (78% and 73% reduction in “hot flush score,” respectively). The effect lasted up to 9 mo after treatment ended. CGRP did not change significantly. Few, minor side effects were reported.Limitations: small number of patients; no placebo control, instead a small group controlled for 6 wk pretreatment. ConclusionsEA and TA lowered number of and distress from hot flushes. The hot flush score decreased 78% and 73%, respectively, in line with or better than medical regimens for these symptoms. Acupuncture should be considered an alternative treatment for these symptoms, but further evaluation is needed, preferably with a non- or placebo-treated control group.