Abstract: A nasal delivery device for a powder, having a reservoir, a delivery head and an air discharge system generating a flow of compressed air. The air discharge system has an air chamber, formed by a hollow axial cylinder, and a piston that sealingly slides in the air chamber to compress the air. The hollow axial cylinder has a radial shoulder connecting a first cylinder portion and a second cylinder portion. Before actuation, the piston is at the first cylinder portions and, during actuation, the piston sealingly cooperates with the second cylinder portion. The radial shoulder defines a profile that the piston overcomes at start of actuation. The piston has an upper lip and a lower lip, a skirt around the hollow axial cylinder with a lower flange projecting radially inward. The skirt has a profile radially projecting towards the inside, cooperating before actuation with the lower lip of the piston.

Abstract: There is described a cartridge for use with an apparatus for heating aerosol generating material to volatilize at least one component of the aerosol generating material. The cartridge includes a first body defining a first chamber and aerosol generating material is located within the first chamber. The first body includes a first base including a sheet of heat conductive material and has a first outer surface and at least a major portion of the first outer surface is for contacting a first heating surface of a heater of the apparatus for heating the aerosol generating material within the first chamber.

Abstract: A system and method for measuring the effectiveness of a dose from an inhaler on a user is disclosed. The inhaler includes a drug container and a dosing mechanism coupled to the drug container to aerate a dose from the drug container. The dosing mechanism provides the aerated dose to the user. A sensor interface is in communication with a physiological sensor. The physiological sensor is attached to a user to sense a physiological response to the dose. Physiological data is sent to the sensor interface. A controller is coupled to the sensor interface to collect the sensed physiological data from the user corresponding to the time that the aerated dose is delivered to the user. The effectiveness of the dose may be determined from the collected data. The dose amount or frequency may be changed or the drug may be changed based on the collected data.

Abstract: A mist inhaler device (200) for generating a mist for inhalation by a user. The device comprises a mist generator device (201) and a driver device (202). The driver device (202) is configured to drive the mist generator device (201) at an optimum frequency to maximise the efficiency of mist generation by the mist generator device (201).

Abstract: A system and method for reducing the risk of fire in an oxygen delivery system. The system may include an oxygen delivery device with a controller in communication with a flow control valve to control a flow of oxygen through a tubing from an oxygen source to a patient interface. The controller may be programmed to close the flow control valve for a predetermined time period at a predetermined time interval to cause a periodic oxygen pause, the periodic oxygen pause to remove oxygen that may serve as an oxidizer when a fire is present inside at least one of the patient interface and the tubing.

Abstract: Provided are a method for controlling oxygen-containing gas output by an oxygen provider, The method includes: acquiring a first pressure measurement of the oxygen-containing gas at the oxygen provider side; determining a pressure estimation of the oxygen-containing gas at the patient side based on the first pressure measurement, wherein the oxygen-containing gas experiences a pressure drop on the gas pathway to arrive at the patient side; and controlling a target parameter of the oxygen-containing gas output by the oxygen provider based on the pressure estimation. With the method or device for controlling oxygen-containing gas output by an oxygen provider, an automated solution to control the oxygen-containing gas based on a pressure measurement at the oxygen provider side is provided, and the complexity of a medical device for oxygen therapy is reduced.

Abstract: The present disclosure relates to a monitoring device for measuring and monitoring breathing parameters and, optionally, oxygenation and/or vital sign parameters of a mechanically ventilated patient, the monitoring device being removably arrangeable at a portion of a ventilator breathing circuit provided between and in fluid connection with a mechanical ventilator and an airway of the patient. The monitoring device comprises a first sensor arrangeable at the fluid connection for measuring parameters related to an airflow in the fluid connection to obtain measurement data; a processor adapted to receive the measurement data from the first sensor and configured to process the measurement data into at least one breathing parameter; and a transmitter adapted to transmit data comprising the at least one breathing parameter to an external device.

Abstract: Methods and apparatus, such as a controller of a respiratory therapy device, generate a signal representing an estimate of flow rate of gas flow from the device. The respiratory therapy device may include a motor-operated blower. The method may include receiving in the controller, signals generated by a set of sensors, including measures of pressure and frequency (e.g., speed) of the motor. The controller may be configured to compute an entrained air density function and generate the estimate signal based on a function of the measures of pressure and frequency, and the entrained air density function. The entrained air density function may apply signals from additional sensors, such as atmospheric pressure, gas temperature, and ambient relative humidity, to compute atmospheric density. Control operations of the therapy device may then be based on the estimated signal, which may be applied to assess accuracy of a signal from a flow sensor.

Abstract: A laryngoscope for orotracheal intubation, includes a tubular body that serves as a guide for an endotracheal tube. The tubular body has an adjustable head which is inserted into the pharynx through the mouth following the anatomical curvature until it reaches the larynx and vocal cords. The head may be equipped with a lighting and display system that can be connected to an external screen.

Abstract: A cushion for a respiratory mask is provided. The cushion includes a face contacting portion, a non-face contacting portion and an intermediate region. The face contacting portion is formed from an open cell foam material and includes an opening to provide, in use, a source of breathing gas to a user's airways. The non-face contacting portion is formed from an elastomeric material. The intermediate region is formed between the face contacting portion and the non-face contacting portion. Open cells of the open cell foam material in the intermediate region are filled with the elastomeric material.

Abstract: An air flow system cannula is disclosed. The air flow system cannula comprises: a body having a radius of curvature less than about 180 degrees, the body including two solid portions and an adjustable portion provided between the two solid portions for additional flex and angular contouring, two nasal posts, and two end portions. The adjustable portion can collapse to a plurality of positions. The air flow system cannula can also include an adjustable frame that provides additional structural integrity. The adjustable frame is inserted into the body, snap-fit to the body, pressed-fit to the body, or directly molded in the body.

Abstract: This disclosure provides a directional adjustment unit for a headgear for a respiratory mask The directional adjustment unit provides an increased resistance to extension of one or more straps of the headgear when the headgear is under tensile forces, as compared to a lower resistance to retraction of the one or more headgear straps. The directional adjustment unit comprises a movable frictional engagement member comprising an aperture, wherein the aperture is arranged to receive a filament of a strap of the headgear therethrough, wherein the frictional engagement member in a first configuration provides a disengaged or pre-activated configuration with respect to the filament, and in a second configuration provides an engaged configuration with respect to the filament. Features are provided which improve the operation of such a directional adjustment unit.

Abstract: Medical breathing tubes have a tubular body that defines a lumen extending between open terminal ends of the tubular body. An internal form is enclosed within the lumen and supportive of the tubular body. The internal form may be a coated encapsulated internal form where the coating secures the internal form to the tubular body. The internal form may provide for a series of alternative crests and troughs of the tubular body. A patient interface and/or a securement system may be attached to the tubular body.

Abstract: An adapter (1) for establishes a flow channel (2) between a breathing gas supply and a patient connection piece. A set (20) and a system (30) for ventilation or respiratory support, each include the adapter (1). The adapter (1) includes a first connection structure (3) configured to connect to the breathing gas supply and a second connection structure (4) configured to connect to a patient connection piece. A bypass channel (5) branches off from the flow channel (2) and is provided with an extraction opening (7) which can be closed at least temporarily by a safety valve (6). The safety valve (6) is configured such that the extraction opening (7) is closed when a ventilation pressure prevailing in the flow channel (2) is lower than a pressure prevailing on a side of the safety valve facing away from the flow channel (2).

Abstract: A method of an apparatus control pressure in the patient interface. A vent valve may be used with a respiratory device, where the vent valve may selectively block fluid communication between components, such as the flow generator, the patient interface, and/or the vent. An expiratory flow model may be used to determine an expiratory characteristic such as an expiratory flow rate or pressure in the patient interface where an indicative measure may not be available. The expiratory flow model may receive inputs based on a measure of the patient's respiration, such as the tidal volume, peak inspiratory flow rate or length of inspiration. The expiratory characteristic may be used by a controller to control a pressure in the patient interface to provide respiratory therapy to a patient at or close to a target pressure.

Abstract: A bi-level positive airway pressure device includes a housing that has a patient port for connecting to an airway of a patient. There is a device (e.g., a nozzle) for generating a positive airway pressure that is directed through a conduit towards the patient port. An exhalation detector includes a nozzle emitting a jet of a gas directed across the conduit and directed at a receptor channel when exhalation gases flow from the patient port, thereby an increase a gas pressure is present at the receptor channel when the exhalation gases flow from the patient port. The exhalation detector converts the increase in the gas pressure into a movement of an occluding member such that when the exhalation gases flow from the patient port, the occluding member moves to block the means for generating the positive airway pressure.

Abstract: A valve with an internal member is disclosed which allows exhaled carbon dioxide to escape from a breathing circuit when the circuit gas pressure drops below a threshold pressure. The valve operates by occluding one or more ports under a relatively high pressure and opening the one or more ports under a relatively low pressure. The internal member is attached to the body of the valve at two or more locations on the internal member. The internal member moves in a direction perpendicular to the gas flow through the valve.

Abstract: Systems and methods disclosed herein relate to augmenting a treatment modality. A method of providing stimulation therapy to a user may include generating transcutaneous vibratory output comprising one or more variable parameters, subjecting the user, in conjunction with the transcutaneous vibratory output, to a treatment modality, wherein the one or more variable parameters of the transcutaneous vibratory output comprise at least one of a perceived pitch, a perceived beat, a perceived intensity, an envelope, or a base tone, and at least one of selecting or modifying the one or more variable parameters of the transcutaneous vibratory output to augment the treatment modality.

Abstract: In some embodiments, an external bladder management system that is configured to reside within a urine collection receptacle (e.g., a toilet) includes a body that houses a fluid testing chamber. The fluid testing chamber is fluidically coupled to a fluid inlet and a fluid outlet. The system further includes a fluid capturing funnel fluidically coupled to and extending from the body and configured to couple the body to the urine collection receptacle. The system further includes an optical sensor disposed within the body and including (1) an emitter configured to convey light across the fluid testing chamber, and (2) an optical detector capable of measuring an intensity of the light as the light exits the fluid testing chamber. The fluid inlet, fluid testing chamber, and fluid outlet are collectively configured to encourage a laminar flow profile of the fluid as it flows through the fluid testing chamber.

Abstract: A catheter adapter may include a distal end, a proximal end, an inner surface extending through the distal end and the proximal end and forming a lumen, and a side port forming a side port pathway through a sidewall of the catheter adapter and in fluid communication with the lumen. The catheter assembly may include a catheter extending distally from the distal end of the catheter adapter. The catheter assembly may include a septum disposed within the lumen proximal to the side port pathway. The catheter assembly may include one or more features to facilitate flushing of the catheter assembly: a diameter of the side port may increase in a distal direction; a portion of the inner surface proximal to the catheter and distal to the septum may include multiple grooves; the side port pathway may include a non-cylindrical portion; an insert; a rotation element; and a pivot element.

Abstract: According to one aspect, a method for removing material from a body lumen is disclosed. The method may include positioning a first medical device within the body lumen; and expanding an expandable member at a distal portion of the first medical device from a retracted state to an expanded state. The expandable member may abut the body lumen in the expanded state. The method may further include providing fluid to a fluid lumen of the first medical device, wherein the fluid is deployed into the body lumen; applying an ultrasound signal to the first medical device from a second medical device; and moving the first medical device distally through the body lumen while the expandable member is in an expanded state, to remove material from the body lumen.

Abstract: Catheter shafts and associated devices, systems, and methods are disclosed herein. A representative catheter in accordance with an embodiment of the disclosure includes a generally tubular outer structure and an inner structure surrounded by the outer structure. The inner structure surrounds a catheter lumen. The inner structure includes over-lapping edges such that, when the catheter is bent along its longitudinal axis, the over-lapping edges move relative to one another.

Abstract: A catheter includes a catheter shaft, an operating portion coupled to a proximal end portion of the catheter shaft, and at least one operating wire. A distal end portion of each operating wire is fixed to a distal end portion of the catheter shaft, and a proximal end portion of each operating wire is fixed to the operating portion or the proximal end portion of the catheter shaft. The operating portion includes a first rotary member. The first rotary member makes relative rotation with respect to the catheter shaft around an axis parallel to an extending direction of the proximal end portion of the catheter shaft to change a tensile force of the operating wire and thus change a degree of bending of the distal end portion of the catheter shaft.

Abstract: A urethral catheter. A cavity is formed at the head end of the urethral catheter, and an internal span of the cavity is greater than that of an opening. A check device (2) located at the front end of a guide core (5) is received in the cavity, and the check device (2) is a guide core (5) that can be retracted into a guide core catheter (4) and can move within the guide core catheter (4). The guide core (5) can expand outward after moving out of the guide core catheter (4). The span of the top of the expanded guide core (5) is greater than the outer diameter of the opening of the cavity at the head end of the urethral catheter.

Abstract: A percutaneous urinary catheter configured to be deployed in a urinary tract, including: (a) a proximal portion; and (b) a distal portion including a retention portion configured to be deployed in a kidney and/or a renal pelvis, the retention portion including one or more drainage holes leading to one or more lumen(s) within the proximal portion, wherein the retention portion, when deployed, defines a three-dimensional shape sized and positioned to maintain patency of fluid flow between the kidney and/or renal pelvis and a proximal end of the catheter by inhibiting mucosal tissue from appreciably occluding the one or more drainage holes when negative pressure is applied through the catheter.

Abstract: A catheter assembly may include a catheter adapter, which may include a distal end, a proximal end, an inner surface extending through the distal end and the proximal end and forming a lumen, and a side port forming a side port pathway through a sidewall of the catheter adapter and in fluid communication with the lumen. The catheter assembly may include a catheter extending distally from the distal end of the catheter adapter. The catheter assembly may include a septum disposed within the lumen proximal to the side port pathway. A portion of the inner surface proximal to the catheter and distal to the septum may include one or more of the following: a textured surface, a channel configured to direct fluid flowing into the lumen from the side port, a protrusion extending inwardly into the lumen opposite the side port pathway, and an annular shoulder.

Abstract: An introducer hub assembly, such as an introducer hub assembly of a leadless cardiac pacemaker, including a hemostatic seal having a cross-slit configuration, is described. The hemostatic seal can be retained between a hub cap and an introducer hub. The hemostatic seal includes a first section having first slits intersecting along a longitudinal axis of the introducer hub, and a second section having second slits intersecting along the longitudinal axis. The first slits are angularly offset relative to the second slits to reduce a likelihood that fluid will leak directly through the seal. Other embodiments are also described and claimed.

Abstract: A steerable medical device, such as an endoscope of an endoscopic system, including a handle and an elongate shaft extending distally from the handle to a distal tip, a motor control assembly including a motor control housing configured to detachably interface with the handle, wherein the motor control assembly includes a first motor disposed within the motor control housing and a first gear assembly disposed within the motor control housing, and a first drive axle configured to engage the first gear assembly with a first deflection mechanism disposed within the handle, the first deflection mechanism being configured to deflect the distal tip in a first plane.

Abstract: A catheter may include a tubular member having a lumen and an outer surface, a sleeve configured to be positioned in the lumen in a retracted configuration and to evert over at least a portion of the outer surface in an everted configuration, and a filament configured to retract the sleeve into the retracted configuration. The catheter may include an aperture proximal of a distal end, where the filament extends through the aperture from the lumen. A pull member may be on a distal end of the filament. The filament may be looped, coiled, and/or bunched in the catheter when the sleeve is in the retracted configuration. A shuttle may be attached to a distal end of the sleeve, where the shuttle includes a tubular member configured to maintain patency of the sleeve, and the filament engages the shuttle to retract the sleeve into the lumen.

Abstract: A catheter or shaft, such as a distal access support or aspiration catheter, is provided that is configured to be advanced at least partially within a patient. The catheter or shaft may include a flexible and hollow shaft including a proximal end and a distal end. The flexible and hollow shaft may include a slotted portion with a plurality of slotted openings, the slotted portion including a first segment with a first pattern of slotted openings and a second segment extending proximally relative the first segment with a second pattern of slotted openings different from the first pattern.

Abstract: An IV catheter system may include a catheter component with a catheter hub, a cannula extending distally from the catheter hub, and a securement platform. The securement platform may include a wing, which may extend from the catheter hub. The IV catheter system may also include a needle component with a needle hub, a needle extending distally from the needle hub along an axis, and a grip extending from the needle hub. The grip may be generally parallel to the axis and disposed on a side of the needle hub. The wing and the grip may be positioned to facilitate manipulation with a single hand to move the IV catheter system from an insertion configuration towards a fluid delivery configuration.

Abstract: A medical liquid injection device including a catheter with a hollow shaft having a lumen formed inside to contain medical liquid, a wire to be inserted into the lumen, and a wire moving device to move the wire forward inside the lumen from a proximal end to a distal end side in accordance with a control signal, thereby ejecting a predetermined amount of the medical liquid from the distal end of the hollow shaft.

Abstract: A tool for inserting a catheter into a body of a patient is provided. The tool comprises: a housing in which at least a portion of the catheter is initially disposed; a needle distally extending from the housing, at least a portion of the catheter disposed over the needle; a guidewire initially disposed within the needle partially; and an advancement assembly for distally advancing the catheter. The housing comprises: a first portion comprising a distal part and a proximal part; and a second portion engaged with the first portion, wherein the distal part of the first portion is configured to be able to distally slide with respect to the second portion to release the engagement between the first portion and the second portion. The advancement assembly includes a safety cap which is initially disposed over the needle and is configured to be locked to the housing when distally sliding to a position of isolating the tip of the needle within the safety cap.

Abstract: Rapidly insertable central catheters (“RICCs”), RICC insertion assemblies, and methods are disclosed. For example, a RICC insertion assembly can include a RICC, an introducer, and an access guidewire. An introducer needle can include a needle shaft having a longitudinal gap extending from a proximal portion of the needle shaft through a needle tip. An introducer sheath can include a splittable sheath hub coupled to a splittable sheath body. The introducer sheath can be disposed over the introducer needle with the sheath body sealing the needle shaft for drawing a vacuum through the introducer needle. The access guidewire can extend along an entirety of a primary lumen of the RICC, through a splittable valved port of the sheath hub, along a sheath body-covered needle channel of the needle shaft, and to a location in the introducer proximal of the needle tip in a ready-to-operate state of the RICC insertion assembly.

Abstract: Devices and methods for management of a guidewire during catheter insertion. Particular embodiments include unidirectional valves to allow movement of a guidewire in one direction only.

Abstract: Provided herein is an endovascular procedure system including a first drive unit comprising a first drive assembly having a first rotational actuator and configured to be mechanically coupled to a first endovascular insertion device advance assembly of a first cassette, a second drive unit having a second drive assembly, the second drive assembly having a second rotational actuator and configured to be mechanically coupled to a second endovascular insertion device advance assembly of a second cassette, a third drive unit comprising a third drive assembly having a third rotational actuator and configured to be mechanically coupled to a third endovascular insertion device advance assembly of a third cassette and a track, to which the first drive unit is fixedly coupled, the second and third drive units are moveably mechanically coupled, and the second drive unit is disposed between the first drive unit and the third drive unit along the track.

Abstract: A device for reducing pressure within a lumen includes a reservoir structured for holding a fluid therein, an injection port in fluid communication with the reservoir, a compliant body structured to expand and contract upon changes in pressure, and a conduit extending between and fluidly coupling the reservoir and the compliant body. The fluid may be a compressible or a noncompressible fluid.

Abstract: A scalp treatment applicator assembly includes a tube which contains a fluid scalp treatment. A cone is fluidly coupled to the tube and the cone is in fluid communication with an interior of the tube to receive the fluid scalp treatment. The cone tapers to point to penetrate the user's hair to apply the fluid scalp treatment to the user's scalp without disturbing the user's hair. A bulb is removably attachable to the tube and the bulb is comprised of a resiliently deformable material such that the bulb can be compressed by the user. The bulb is in fluid communication with an interior of the tube when the bulb is attached to the tube to urge the fluid scalp treatment outwardly through the cone when the bulb is compressed.

Abstract: A skin treatment device includes a control unit and a hand tool. The hand tool includes a body, a wiper head, and a needle roller head. The wiper head includes a rotatable wiper structure including one or more wiper blades. The needle roller head includes needle roller structure. The skin treatment device provides a multi-step process including desincrustation, skin transdermal delivery of topical agents, serums, and the like, microdermabrasion, and fractional micro-channeling application.

Abstract: The present invention provides a method for treating a skin neoplasm in a subject, comprising administering to the subject's skin a composition comprising an effective amount of one or more antineoplastic agents, wherein the composition is administered with a microneedle delivery device.

Abstract: An apparatus and method for manufacturing a microneedle are disclosed, which aim to reduce the production costs of microneedle preparation and improve the efficiency and quality of microneedle preparation. The apparatus for manufacturing a microneedle includes a baseplate, an elastomeric female mold, a horizontal movement mechanism, a vertical movement mechanism, a dispenser and a roller mechanism. The elastomeric female mold is disposed on the baseplate and has a surface formed thereon with cavities complementary to needle bodies. The dispenser includes a reservoir for holding a solution for forming the microneedle. The roller mechanism is disposed on the dispenser and includes a roller.

Abstract: The present invention is directed to an applicator, configured to reversibly attach to a dispensing device, with at least one micropore and a kit for administration of a therapeutic agent. Methods of use of the applicator are also disclosed herein.

Abstract: The present invention provides a solution to increase the drug loading capacity and drug delivery precision of dissolving microneedles. These solutions include: (a) increasing the base of the microneedle cavities without substantially changing the microneedle's height and geometry, (b) use of drug suspension and (c) a specific centrifugation order for filling drug and matrix material. In the first preferred embodiment, a microneedle master mould comprising a plurality of microneedles, wherein each of the microneedles further comprising a chamfered base which extends to and adjoins with its neighboring chamfered bases is provided.

Abstract: Described are surgical tools to facilitate the proper implantation beneath the outer layer of tubular anatomical structures, or ductus, to include vessels, the trachea, esophagus, gut, and ureters, as well as the outer layer or within the parenchyma of organs, glands, or other tissue, of medicinal, magnetically susceptible, magnetized, and/or radiation-emitting spherules sized in proportion to the substrate structure. Spherule insertion tools expedite insertion transluminally to implant the wall surrounding a lumen making possible therapy and/or extraluminal stenting which leaves the lumen clear for subsequent passage. Spherules can also be introduced into deeper tissue through a ‘keyhole’ incision at the body surface. For evolving methods calling for the placement of numerous ‘seeds’ and/or boluses, eliminated are the need for more extensive incision with increased trauma, procedural duration, and healing time.

Abstract: A magnetically driven tattoo machine is disclosed, which has a substantially radially symmetric exterior shape and be driven by a sensor-controlled electromagnetic coil. The machine has no oscillating mechanical components, and thus reduces or eliminates vibration. The machine may include a housing mechanically isolated from a needle cartridge or subcomponents that can be disassembled and sterilized. The electromagnet may be controlled by a sensor integral with the coil, housed within the machine, or within an external power supply. The machine may be powered by internal battery or by an external power source. The machine may also be controlled wirelessly.

Abstract: A drainage liquid sampling system is disclosed and includes a connector couplable with a drainage tube of a drainage system, the connector defining an inlet port, an outlet port, and a sample port, where the inlet port, the outlet port, and the sample port are in fluid communication with each other, and a sample container couplable with the sample port. A valve within the connector selectively allows and prevents flow of drainage liquid into the sample container. A cap couplable to the sample container also includes a valve. A system for draining liquid from a patient includes the drainage liquid sampling system.

Abstract: A flow modulation device is positioned around a hemodialysis fistula or a graft and includes a non-expandable outer jacket with an inwardly-inflatable flow-modulation chamber positioned inside thereof. The flow modulation chamber is configured to be in fluid communication with a control chamber via a flexible catheter. The control chamber includes a puncture-resistant housing having an inner cavity covered by a self-sealing elastic membrane sealingly attached thereto and configured for repetitive needle punctures. Upon injection of fluid into the control chamber via a needle puncture, the flow modulation chamber inflates inwardly to compress the hemodialysis fistula or the graft causing a reduction of blood flow therethrough.

Abstract: A delivery adapter which may be used as an interface between a syringe and a catheter hub is described.

Abstract: A tool for engaging and disengaging connectors. The tool includes a longitudinal member and at least one aperture extending through the member. The aperture is sized and shaped to receive and retain a connector, and is configured to rotate the connector to engage and disengage the connector with a mating connector. In some of the embodiments a pair of such tools are utilized, one tool holding a first connector and a second tool holding a second connector. In these embodiments one tool may be held stationary while the other tool is rotated to engage and disengage the connectors as desired. Alternatively, both tools may be simultaneously rotated in opposite directions engage and disengage the connectors as desired.

Abstract: A check valve for use in a fluid pathway. The check valve may have a diaphragm and a plurality of supports extending from the diaphragm. The check valve and supports have a line of symmetry, and deformation of the check valve as it moves from a closed position to an opened position can be generally along the line of symmetry.