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At least 19 recordsLinked to original sources
PubMed1992

Comparison of two needle lengths in regional ophthalmic anesthesia with etidocaine and hyaluronidase.

The effect of needle length on the efficacy of regional ophthalmic anesthesia in conjunction with cataract surgery was studied in 97 patients using a two-site injection technique. The local anesthetic used was etidocaine 1.5% with hyaluronidase. In 48 patients, the anesthetic was administered inferolaterally with a 22-millimeter needle, and in the other 49 patients, with a 31-millimeter needle. Every patient had a medial injection with a 12-millimeter needle to achieve lid akinesia and to complete the globe akinesia. At 5 minutes, lid akinesia was considered better in the 22-millimeter needle group (P < .005). After one supplemental dose, when necessary, complete globe akinesia was achieved at 15 minutes significantly more often (94% vs 79%) in the 31-millimeter needle group (P < .05). Lid akinesia in the two groups was identical at that time. Eight patients in the short-needle group and three in the long-needle group experienced some pain during surgery. Throughout the study, the required intraorbital anesthetic volumes were smaller in the 31-millimeter needle group. We recommend the use of a 31-millimeter needle inferolaterally in combination with a 12-millimeter needle medially to achieve satisfactory regional anesthesia for cataract surgery.

Aged↗
PubMed1992

Analysis of the metallic composition of orofacial talismans.

Four metallic talismans, commonly called "charm needles" in Southeast Asia, were surgically removed from the facial soft tissues of three patients. The talismans were found to be superficially placed and were not corroded. The average length of the needles was 8.14 mm, and average diameter was 0.47 mm. They were found to contain an average gold content of 89.75% and an average copper content of 10.25%.

Foreign Bodies↗
PubMed2026

Analyzing the impact of subcutaneous injection needle, device, and administration characteristics on patient pain, anxiety, and safety: a systematic literature review.

The subcutaneous (SC) injection route is a commonly used and important method for therapeutic delivery of a wide range of compounds, and needle characteristics have a significant influence on patient pain, anxiety, safety, and other outcomes. This systematic review evaluates the evidence on how needle-specific characteristics (e.g. gauge, length, tip design, wall thickness, concealment) and administration- or device-related factors can affect patient-reported outcomes and clinical safety indicators during and following SC injections. A comprehensive search was conducted in MEDLINE, PubMed, Embase, and ClinicalTrials.gov in June 2024. Studies were included if they assessed the relationship between needle characteristics and pain, anxiety, safety, or related outcomes in individuals receiving SC injections. A dual-reviewer process was used for study selection, data extraction, and quality assessment. Sixty-two studies met inclusion criteria. Evidence consistently indicated that thinner and shorter needles reduced patient-reported pain and adverse events such as bruising and bleeding. Tapered and lubricated needles, hidden or retractable needle designs, and use of autoinjectors or prefilled syringes also contributed to reduced anxiety and improved user satisfaction. However, results were heterogeneous, and many studies lacked sufficient power or single-variable evaluation of individual needle parameters, limiting definitive conclusions. Needle characteristics significantly influence patient experience and safety with SC delivery. While both clinical evidence and practical experience clearly favor thinner, shorter, and concealed needles, further standardized, high-quality research is needed to isolate and quantify the specific contributions of individual needle characteristics to optimize injection practices and support patient-centered device design.

Humans↗
PubMed1992

Highly variable anticoagulant response after subcutaneous administration of high-dose (12,500 IU) heparin in patients with myocardial infarction and healthy volunteers.

BACKGROUND: In this study, the anticoagulant response of 12,500 IU heparin s.c. was investigated in patients with myocardial infarction and healthy volunteers to determine variabilities in response and modifying factors. METHODS AND RESULTS: On the fourth day after thrombolytic therapy, blood samples were taken before and at frequent intervals until 10 hours after the injection of 12,500 IU heparin s.c. Plasma anti-Xa activity, anti-IIa activity, and the activated partial thromboplastin time (APTT) were measured in addition to body weight and thickness of the abdominal subcutaneous fat layer. Contrary to expectations, the increase of anti-Xa activity, anti-IIa activity, and APTT compared with baseline (predrug) levels was very small, with an average maximal APTT of 42.6 seconds (SD, 12.4 seconds; range, 30.4-70.7 seconds). Subsequently, the influence of the length of the injection needle on the anticoagulant effect of 12,500 IU heparin s.c. was studied in 10 healthy volunteers to find a factor that could be responsible for the poor response in the patients. The length of the injection needle did not influence the anticoagulant effect of heparin. Large interindividual and intraindividual variabilities were seen in the volunteers. The majority of volunteers had minimal prolongation of the APTT, but very strong prolongation was also seen (maximal APTT, 163 seconds). There was no correlation between the abdominal skinfold thickness and anti-Xa activity, anti-IIa activity, or APTT (p > 0.05), but in the patient study, there was a correlation between weight and anti-Xa activity and anti-IIa activity (p < 0.05), and in the volunteer study, there was a correlation between weight and anti-Xa activity and APTT (p < 0.05). CONCLUSIONS: Subcutaneous administration of heparin in a fixed dose for prophylactic and therapeutic purposes may be inadequate because of the large interindividual and intraindividual variations in anticoagulant effect.

Adult↗
PubMed1976

Crystallization of DNA fragments from water-salt solutions, containing 2-methylpentane-2,3-diol.

Fragments of calf thymus DNA have been crystallized by precipitation from water-salt solutions, containing 2-methylpentane-2,3-diol (MPD). DNA crystals usually take the form either of spherulites up to 100 mu in diameter or of needles with the length up to 50 mu. No irreversible denaturation of DNA occurs during the crystallization process. X-ray diffraction from dense slurries of DNA crystals yields crystalline powder patterns.

Cacodylic Acid↗
PubMed1992

[Concentration and form of asbestos fibers in tap drinking water contaminated from a water supply pipe with asbestos-cement].

The identification and concentration of asbestos fibers in tap drinking water supplied in a central area of Akita Prefecture, Japan, were determined by phase-contrast microscopy and a scanning electron microscope equipped with an energy-dispersive X-ray microanalyzer. The following results were obtained. 1. Asbestos fibers were found in the tap water from two areas in which an asbestos-cement pipe was used for public water supply. The concentrations of asbestos fibers in the tap water were 2.7 x 10(4) to 27.0 x 10(4) fibers per liter of water in area A and 10.0 x 10(4) to 21.0 x 10(4) in area B. On the other hand, no asbestos fiber contamination was observed in tap water of area C, which shared a common water source with area A. A vinyl chloride pipe was used over the entire length of the water supply in route C. 2. Crocidolite was the predominant type of asbestos fiber detected in the tap water. Chrysotile and a mixture of chrysotile and amosite were also observed. 3. Almost all asbestos fibers detected in the tap water possessed the form of thick or sheaved fibers with lengths ranging from ca. 5 to 10 microns. Their shapes were very different from those of asbestos fibers found in the atmosphere. The typical form of the latter is short (ca. 1 micron in length) and needle-like. 4. It was suggested that the contamination of asbestos fibers in the tap water was caused by erosion and peeling off of the inner wall of the asbestos-cement pipe used as a conduit. In order to evaluate the safety of drinking water in Japan, an extensive survey on asbestos-fiber contamination in tap water is necessary.

Asbestos↗
PubMed1992

An evaluation of a combined spinal/epidural needle set utilising a 26-gauge, pencil point spinal needle for caesarean section.

We have conducted a prospective study into the ease of use and incidence of postdural puncture headache with the 'Portex' combined spinal/epidural set. The pack contains a 16-gauge Tuohy needle of standard 8 cm shaft length with a matching 26-gauge pencil point spinal needle. The study included 150 consecutive combined spinal/epidural anaesthetics for lower segment Caesarean section. Eighty-eight percent of the cases fulfilled the criteria as technically perfect, i.e. cerebrospinal fluid obtained at the first attempt after identifying the epidural space. There were two cases of significant postdural puncture headache requiring blood patch due to puncture by the 26-gauge spinal needle giving an incidence of 1.3%. This compares favourably with previously reported rates in obstetric patients.

Anesthesia, Epidural↗
PubMedDate not supplied

Biomechanical performance of laser-drilled and channel taper point needles.

The purpose of this study is to evaluate the biomechanical performance of laser-drilled and channel needle swages. The laser-drilled swages have a more uniform circumference that encounters lower drag forces than the channel needle swages. In addition, the length of the laser-drilled hole is shorter than that of the channel needles, allowing the physician to grasp the laser-drilled needle close (3 mm) to the needle end without deformation. These benefits of laser-drilled swages indicate that they should replace all channel needles.

Biomechanical Phenomena↗
PubMed1979

Expanded polytetrafluoroethylene graft fistula for chronic hemodialysis.

In a retrospective study of 66 PTFE arteriovenous fistulae and 71 BCH arteriovenous fistulae for dialysis access, PTFE had a higher patency rate than BCH at 12 months (62.4 versus 32.5%). PTFE was easier to work with and easier to handle in the face of infection. The lateral upper arm approach to placement of the PTFE graft is desirable in patients who have had multiple previous access procedures because this area is usually free from scarring, is distant from neurovascular structures, and provides a greater length of graft for needle punctures.

Aneurysm↗
PubMedDate not supplied

[The technique of stitching a corneal patch in corneal grafting].

One of the main problems of corneal transplantation is the postoperative astigmatism. In the last period the intraoperative application of the kerato-scope, new type of needles and threads in stitching the corneal patch created a chance for solving this problem. The authors present the methods used for stitching of the corneal patch, their advantages and the defects with consideration of differences resulting from the thickness and kind of the thread, from the length and form of the needle. Basing on personal experience and data from the literature they propose the technique of the suture which they are using.

Astigmatism↗
PubMed1979

Calcification of aging articular cartilage in man.

Calcification of the articular cartilage was studied ultrastructually using normal femoral heads obtained from necropsies of persons ranging in age from 11 months to 80 years. Mineral crystals which appeared during the initial stages of deposition were morphologically divided into two types. Type A crystals were slender, twisted and curved, measuring from 100 nm to 360 nm in length. Type B crystals were short, needle-like and slightly curved, measuring from 30 nm to 160 nm in length. Type A crystals were found mainly in the developing epiphysis during childhood. Type B crystals were generally found in the calcified zone of adult articular cartilage. Both types of crystals initially appeared in close proximity to extracellular membrane-invested electron dense particle called "matrix vesicles", and gradually increased in number to form calcified cartilage matrix. The morphological differences between type A and B crystals might be caused by biochemical alterations of the cartilage matrices and/or biomechanical changes in the joints of children and adults.

Adolescent↗
PubMed1978

Design and testing of a new electrode for laryngeal electromyography.

Electromyography of the intrinsic laryngeal muscles has not been widely used, partly because of the difficulty of accurate insertion and stabilization of existing electrodes. The sampling portion of our original electrode has been redesigned. Two needle electrodes, 4 mm in length, protrude from a truncated coneshaped, nonconducting body that has been fashioned to sit in the laryngeal ventricle. The depth of insertion is controlled, and the device resists accidental extrusion.

Electrodes↗
PubMedDate not supplied

Formation of bioerodible polymeric microspheres and microparticles by rapid expansion of supercritical solutions.

Polyhydroxy acids [poly(L-lactic acid) (L-PLA), poly(D,L-lactic acid) (DL-PLA), and poly-(glycolic acid) (PGA)], biocompatible and bioerodible polymers that are being investigated for controlled delivery of pharmaceuticals and are approved by the Food and Drug Administration for in vivo sutures and bone repair implants, have been dissolved in supercritical CO2 and precipitated by rapid expansion of the resulting supercritical solutions (RESS). The formation of these microparticles and microspheres is a first step toward the goal of producing, in a single processing step, drug-loaded polymeric microspheres for use in controlled release applications. Nucleation of poly(L-lactic acid) from CO2 and CO2-acetone mixtures produced microparticles and microspheres ranging from 4 to 25 microns. Microspheres (2-20 microns) were also obtained with chlorotrifluoromethane as solvent. Commercial L-PLA precipitated after extraction of low molecular weight oligomers showed degradation kinetics similar to that of the starting material. The precipitation of DL-PLA from CO2 produced irregular-sized particles (10-20 microns). PGA, a polymer insoluble in most organic solvents, was found to be soluble in supercritical CO2. Nucleation of PGA from CO2 produced both regular-sized particles and needles of 10-40-microns length. The total solubility of commercial L-PLA in supercritical CO2 at 250 bar and 55 degrees C decreased from 0.14 wt % to less than 0.05 wt % and then leveled off as the cumulative flow of CO2 per unit mass of L-PLA loaded in the extractor increased beyond 20 standard L of CO2/g of L-PLA. Use of acetone (1 wt %) as a cosolvent increased L-PLA solubility by approximately 500%.

Biocompatible Materials↗
PubMed1979

Operating microscope, microsurgical instruments and microsutures.

A comprehensive knowledge of operating microscope, microsurgical instruments and microsutures is most essential for any beginner in this field. Magnification provided by an operation microscope is higher and variable to suit microsurgical procedures. Although zoom magnification and focussing are preferable for convenience, microscopes with manual controls can be used for clinical and experimental work. A beam splitter and camera equipment are essential accessories. Microsurgical instruments are delicate and expensive and must be bought with discretion and carefully protected. Fine dissecting forceps, needle holder, microscissors, microvascular clamps and clips and fine haemostats are the only essential instruments. Others are optional. Microsutures form the most expensive part of the microsurgical setup. 10-0polyamide suture mounted on a curved round bodied needle of 4 or 5 mm length is adequate for virtually all clinical and experimental microsurgical work.

Fiber Optic Technology↗
PubMed1992

Insulin injection site tissue depths and localization of a simulated insulin bolus using a novel air contrast ultrasonographic technique in insulin treated diabetic subjects.

Subcutaneous adipose tissue depth was measured in 50 randomly selected Type 1 diabetic patients by real-time ultrasound at five standard sites commonly used for injection. Tissue depths were often less than the length of the standard insulin syringe needle (12-13 mm) at the arm and thigh injection sites, especially in men. Thus, if the currently recommended perpendicular injection technique were to be employed, there would, in theory, be an appreciable risk of intramuscular insulin deposition. In order to determine the true site of deposition in those at risk (injection site tissue depth of < 12 mm), a novel air-contrast ultrasound imaging technique was developed. A mixture of 0.1 ml of air and 0.2 ml of sterile 0.9% saline was self-injected into an anterior thigh site by 30 subjects using their usual technique. The site of the resultant tissue depot was located by ultrasound. Sixty-three percent of the depots were localized to true subcutaneous tissue and the remaining 37% to between the fascial planes overlying muscle. None of the subjects proved to be injecting into muscle. These results contrast with predictions of the risk of intramuscular injection made from the ultrasound measurement of subcutaneous tissue alone at the anterior and lateral thigh sites of, respectively, 100 and 97% for men and 42 and 37% for women. Although 11 of the 30 subjects claimed to be using a full-depth perpendicular injection technique, on direct observation only four proved to be injecting perpendicularly and none of these to the full depth of the needle.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1992

[Transjugular intrahepatic portosystemic stent shunt (TIPSS) with use of Rösch-Uchida transjugular liver access set--evaluation by CT and its clinical application].

Appropriateness of the Rösch-Uchida transjugular liver access set designed for TIPSS procedure was confirmed, especially about the catheter angle and effective length of the 20 G puncture needle, by CT analysis on three dimensional vascular anatomy of the liver. Clinically, TIPSS using the set was successfully made for two patients, connecting superior right hepatic vein with right portal vein in one patient and middle hepatic vein with left portal vein in another patient with hypoplastic right portal vein. Prior to TIPSS procedure, verification of vascular anatomy on CT images is the key to success of TIPSS in safe.

Evaluation Studies as Topic↗
PubMed1976

[Standardized fluorescein injection in serial angiography (author's transl)].

Maximal initial dye concentration in the retinal arteries is desirable for high quality fluorescein Angiograms and is essential for circulation studies. Such high initial dye concentrations can only be achieved by a very rapid fluorescein injection technique necessitating an automatic injector. A reliable easy to use "spring-injector" has been designed for clinical use (Figs. 1 and 2). A disposable syringe is driven by a spring contained in a metal cylinder. Microswitches are activated by the piston of the injector triggering one exposure each at the beginning and at the end of the injection. Time and duration of the injection are therby permanently documented on the film. The "Terumo Disposable Syringe 10 cc" is used routinely. By interposing a plastic connector between syringe and injector-piston the injection-volume can be reduced to 5 ml. With diffferent connectors one can inject an volume desired up to 10 ml. The duration of the injection can be varied by using different intravenous catheters. Routinely the "VYGON Trocaflex catheter Nr. 125.16" with a needle diameter of 1.1 mm and a length of 30 cm is used resulting in an injection time of 10 ml/1.0 sec or 5 ml/0.5 sec. The largest Trocaflex catheter (No. 125.20) will shorten the injection time to 10 ml/0.5 sec and 5 ml/0.25 sec respectively. Even faster injections can be achieved by shortening the catheter or by using a stronger spring. With the described injector, high-speed, well-standardized fluorescein injections are possible. The intravenous catheter makes parvenous injections impossible and will allow for repeated angiograms even on different days without the need for a new venous puncture.

Fluorescein Angiography↗