Malleable Wire Research Articles

3D Printed frames to enable reuse and improve the fit of N95 and KN95 respirators

BackgroundIn response to supply shortages caused by the COVID-19 pandemic, N95 filtering facepiece respirators (FFRs or “masks”), which are typically single-use devices in healthcare settings, are routinely being used for prolonged periods and in some cases decontaminated under “reuse” and “extended use” policies. However, the reusability of N95 masks is limited by degradation of fit. Possible substitutes, such as KN95 masks meeting Chinese standards, frequently fail fit testing even when new. The purpose of this study was to develop an inexpensive frame for damaged and poorly fitting masks using readily available materials and 3D printing.ResultsAn iterative design process yielded a mask frame consisting of two 3D printed side pieces, malleable wire links that users press against their face, and cut lengths of elastic material that go around the head to hold the frame and mask in place. Volunteers (n = 45; average BMI = 25.4), underwent qualitative fit testing with and without mask frames wearing one or more of four different brands of FFRs conforming to US N95 or Chinese KN95 standards. Masks passed qualitative fit testing in the absence of a frame at rates varying from 48 to 94 % (depending on mask model). For individuals who underwent testing using respirators with broken or defective straps, 80–100 % (average 85 %) passed fit testing with mask frames. Among individuals who failed fit testing with a KN95, ~ 50 % passed testing by using a frame.ConclusionsOur study suggests that mask frames can prolong the lifespan of N95 and KN95 masks by serving as a substitute for broken or defective bands without adversely affecting fit. Use of frames made it possible for ~ 73 % of the test population to achieve a good fit based on qualitative and quantitative testing criteria, approaching the 85–90 % success rate observed for intact N95 masks. Frames therefore represent a simple and inexpensive way of expanding access to PPE and extending their useful life. For clinicians and institutions interested in mask frames, designs and specifications are provided without restriction for use or modification. To ensure adequate performance in clinical settings, fit testing with user-specific masks and PanFab frames is required.

Customized wire prosthesis (Devise) for alar collapse in sleep apnoea

BackgroundAlar collapse is known to aggravate snoring-severity and possibly the severity of obstructive sleep apnoea. Various surgical techniques, implants and commercial mechanical/prosthetic nasal alar dilators are evident in literature. Material and methodsA malleable wire prosthesis at ‘no’ manufacturing cost is custom designed through computer modelling and animation and thereafter tested for its efficacy in 20 normal subjects as per visual analog scale along with its correlation with patient-profiles. Observations and resultsAll subjects reported improvement in their nasal patency ranging from 30% to 99% but no correlation was seen between the degree of improvement & patient variables. This improvement in normal subjects indicates even a better improvement in true alar collapse. ConclusionMain advantages of this devise is its extremely low-cost, non-traumatic nature, adjustability to suit patient comfort and can be customised across all types of noses. However it seems cosmetically unacceptable during the daytime, as well as for small children. With no correlation with patient factors the acceptability of this devise is mainly dependent on a good customized design. With a constant use during bedtime in alar collapse this device may not only resolve snoring and improve the sleep-quality of spouse but also enhances oxygenation during sleep.

Assisted resection of lateral extension of juvenile nasopharyngeal angiofibroma using a sphenopalatine fossa dissector.

Juvenile nasopharyngeal angiofibroma often attaches firmly to the adjoining bony region around the sphenopalatine foramina-sphenopalatine fossa-pterygomaxillary fissure. This can result in hourglass-shaped constriction and predispose to incomplete resection (residual disease) with a transpalatal approach. This paper describes attempts to address this 'inaccessible' area with a novel instrument, used since 2012. Measurements of the sphenopalatine foramen, nasal septum, posterior nasopharyngeal wall and hard palate were undertaken in 20 skulls and 10 computed tomography scans (lateral extension). A device was designed (in terms of angulation and length) following several trials with malleable wire. A search of patents was also undertaken. Recurrence rates were compared in cases of device use and non-use. The novelty of the sphenopalatine fossa dissector was established and the device was patented. This device has significantly improved our 17.59 per cent recurrence rate of the past 4 decades; of 63 cases over 3 years, there were only 3 recurrences and 2 residual disease cases. Findings of our previous studies with or without the device are compared. Existing evidence supports the incorporation of this inexpensive instrument in the armamentarium for resecting lateral extension of juvenile nasopharyngeal angiofibroma during a transpalatal approach.

Affordable self-regulating irrigation device for microsurgery using readily available malleable wire and a Silastic tube: a technical note.

A relevant irrigating and flushing maneuver during cerebral microsurgical procedures allows for a neat and optimal operative field. However, when operating on the deep region of the brain, a delicately created slim surgical corridor could unintentionally hinder the assisting surgeon from properly performing this routine maneuver. To address this problem, the authors devised a useful and convenient irrigation system that can be used during cerebral microsurgery. This system only necessitates a readily available silastic feeding tube and a malleable wire. The advantages of our devised system include the convenience of free molding, good endurance of the molded contour, and easy control over the amount of irrigation. In this report, the authors demonstrated technical tips for using this newly devised system.

Occlusal angles of cheek teeth in normal horses and horses with dental disease

The angle between the occlusal surface of the tooth and the horizontal plane of 687 cheek teeth from the skulls of 22 horses without gross dental disorders and 11 horses...

‘Cupping’ the breast—a simple technique used in wire-guided local excision of impalpable breast lesions

Localisation wires are commonly inserted to aid excision of impalpable breast lesions. The wire is usually introduced through a needle and the needle usually removed leaving the wire in place. The wire is malleable, so that its free end can be strapped to the skin of the breast. A disadvantage is that the malleable wire is less easily palpable intraoperatively than the needle. If the needle is left over the guide-wire, the stiffness of the needle usually prevents strapping it to the breast skin especially if it has been inserted at 908 to the skin surface. We describe a simple technique to prevent accidental displacement of the localisation device during wirelocalised excision of impalpable breast lesions.

Malleable microsurgical suction device. Technical note.

✓ A malleable microsurgical suction device is presented which allows continuous drainage of cerebrospinal fluid or blood from an operative site. A malleable wire incorporated into the plastic tubing allows placement and readjustment of the suction tip to keep it where desired.

A simple method for the mensuration of body contour.

Accurate measurement of body contour and the transposition of this contour to the plotting board are integral but tedious parts of all but the most simplified forms of planning for radiation therapy. The use of a rotation therapy unit and a light-beam triangulation device ordinarily employed to measure source-to-skin distances has been found to provide an easy and convenient substitute of comparable accuracy for the more time-consuming conventional methods. The usual technics for the mensuration of body contour, such as those which employ the bending of malleable wire or solder about the part, the use of plaster-cast contours, the spoke-and-wheel device which employs movable radii of measured length, and even the more elaborate projection methods in which cross-sectional contours of the body are projected against a patient's dimensions on the plotting board, are too well known to warrant elaboration here. All are time-consuming procedures which have inherent inaccuracies, probably the most important of which is due to the need for transposing onto the plotting board the location of the tumor to simulate actual conditions of treatment. A system which employs the actual location of the tumor as a fixed point of reference for the measurement of varying tumor-skin radii bypasses some of the inaccuracies of the conventional methods. The body contour and its relationship to the underlying mass are mapped directly on the patient, the only prerequisites being a rotational therapy device capable of 360° rotation and a light-beam source-to-skin measuring device such as that shown in the accompanying figure. This light-beam device is capable of measuring source-to-skin distances of 40 to 60 cm. by adjustment of the light-beam spot to the cross-hair shadow of the field lights, the source-to-skin distance being read directly from the scale on the device. The skin-tumor radius of any desired vector is obtained directly by the simple expedient of positioning the tumor at the axis of rotation. With our unit, which employs a rotational radius of 55 cm., the source-to-skin distance is determined with the light beam and this value is subtracted from 55 cm., the difference representing the skin-tumor radius of the particular vector. The same process is repeated every 30° around the circumference of the part, and within a short time an accurate cross-sectional contour is obtained. Accurate localization of the area to be treated is, of course, essential, but since this is a necessary step preliminary to any technic of body-contour plotting, it need not enter into special consideration with the particular method under description. Once the necessary markings are placed on the skin, conforming to the anteroposterior and lateral co-ordinates of the tumor area, obtained either by localizing roentgenograms or fluoroscopy, the patient is placed exactly as for rotational therapy.