Abstract: Methods, apparatuses and systems are described for implanting a plurality of fiducial markers into a tissue. Systems include a needle, a stylet sized to slide within a lumen of the needle, and a multi-stop stylet spacer having stopping features configured to engage with the stylet to stop the distal end of the stylet at one or more predetermined distances from the distal end of the needle. Methods for implanting a plurality of fiducial markers into a tissue are described and include inserting a needle preloaded with fiducial markers into a tissue, adjusting a multi-stop stylet spacer from a safety position to a first deployment position, deploying a first fiducial marker into the tissue, adjusting the stylet spacer from the first deployment position to a second deployment position, and deploying a second fiducial marker into the tissue.

Abstract: The present disclosure relates to a source wire assembly for radiographic applications, particularly for guiding a gamma ray source through a tubular path, such as with a radiographic projector. The source wire assembly includes a core of flexible metal cable, such as, but not limited to, aircraft cable, which may include wires and/or strands which are woven, twisted, helix wound or braided. A distal end of the source wire assembly is securely engaged to a Radioactive source capsule assembly while a proximal end of the source wire assembly is securely engaged to a connector housing for connection to driving equipment, such as, but not limited to, a push-pull operation associated with a radiographic projector, which may include source wire locking and safety mechanisms.

Abstract: A barrel adapter mountable to a syringe barrel includes a barrel tip, a needle assembly, a stylet assembly slidably disposed within a needle lumen of the needle assembly, and a plug within the lumen of the needle. An implant delivery syringe includes a barrel, a plunger assembly, and the barrel adapter. The syringe may include a needle retraction mechanism having a biasing member and an actuable locking arrangement. When the actuable locking arrangement is actuated, the biasing member causes the needle to axially translate over the stylet during retraction to dislodge the plug and cause delivery of an implant to a target location. The plug may be a biodegradable polymer plug such as a water-soluble polymer, PLGA, and/or CARP. The stylet may be retracted following delivery. Methods of assembling implant delivery syringes with drug implants are also provided.

Abstract: Devices and methods are discussed directed to the use of a low profile laser ablation catheter for use in laser ablation removal of arterial plaque blockages to restore blood flow in the treatment of arteriovenous fistulas. Also discussed are devices and methods directed to packaging, long term storage and sterilization of liquid core ablation catheters.

Abstract: Embodiments include a fiducial deployment system with a handle configured for actuation of same. A fiducial may include one or more protuberances configured to engage one or more slots in a needle of the system. The needle may be configured to deliver a plurality of fiducials to a target location in serial fashion, one at a time. The handle includes an actuation mechanism with a recessible-toothed rack and actuation member(s) configured for incrementally or otherwise controlledly deploying one or more fiducials at a time by advancing a stylet through and/or retracting the body of a slotted needle in which fiducials are disposed with a fiducial protrusion extending into the needle slot, which needle slot also includes retaining structures that do not impede the needle lumen.

Abstract: In one embodiment, a verification system for confirming the position of a conduit inserted within a patient may include an elongate control element dimensioned for insertion within the conduit. The control element has a proximal end and a distal end, and a verification element coupled to a distal region. The verification element may be configured to detect the presence of a reference marker associated with the conduit and communicate a signal indicative of the position of the reference marker relative to the verification element. The control element may also be configured to maneuver the verification element along a length of the conduit.

Abstract: Glaucoma can be treated by implanting an intraocular shunt into the eye. Such procedures can employ various deployment devices, shunts, and implantation techniques.

Abstract: Instruments, systems and methods are provided for efficient loading, indexing and replacement of cartridges for storing, for example, hair grafts. In addition, an improved urging mechanism for expelling hair grafts from a receptacle of a storage cartridge is provided, as well as a method of its operation. Furthermore, cartridges with a plurality of receptacles comprising slots for loading hair grafts are disclosed.

Abstract: Brachytherapy seed insertion and fixation devices and systems to decrease implanted brachytherapy seed migration within tissue and minimize trauma. Component(s) with cavity or opening features are attached to a brachytherapy seed or series of seeds. The cavity or opening features interact with the patient's tissue to fix the seed and component assembly in place and inhibit movement/migration of the seed(s). The cavity or opening features may optionally be filled with an adhesive or other beneficial material. The seed(s) or seed and component assembly may be inserted using a delivery device having a needle through which the seed(s) or assembly are implanted and a stylet extending through the needle to cut tissue and facilitate insertion of the needle. The stylet has a reduced diameter cutting tip to cut a narrow hole in tissue, and a tapered region that stretches the narrow hole to accommodate insertion of the larger diameter needle.

Abstract: The present invention relates to comprehensive systems, devices and methods for delivering energy to tissue for a wide variety of applications, including medical procedures (e.g., tissue ablation, resection, cautery, vascular thrombosis, treatment of cardiac arrhythmias and dysrhythmias, electrosurgery, tissue harvest, etc.). In certain embodiments, systems, devices, and methods are provided for delivering energy to difficult to access tissue regions (e.g. peripheral lung tissues), and/or reducing the amount of undesired heat given off during energy delivery.

Abstract: A portable device for insertion of radioactive seeds in percutaneous interstitial brachytherapy applications is described. The device includes: an elongated main body in form of a handpiece; a shielded container of radioactive seeds, received within the main body and having a rotating drum suitable, in use, to release one or more radioactive seeds from the container; means for driving the rotating drum, activatable by an operator and based on lever mechanisms and gears; and means for introducing one or more radioactive seeds in a body site of interest, comprising a substantially wire-shaped pusher. The pusher urges the radioactive seed(s) released from the rotating drum through a cannula unit.

Abstract: There is provided a therapeutic instrument, for storing a sheet-type therapeutic substance to which a liquid is delivered, and delivering the stored therapeutic substance to an affected part, including: a nozzle member 23 having an opening 34 on a tip end of a tubular part 31 in which the therapeutic substance can be stored, for charging and discharging the therapeutic substance; and a syringe unit 22 that selectively causes a negative pressure and a positive pressure to act in the tubular part 31 through a hole of a valve member 27, wherein the space 33 of the tubular part 31 is the space for sucking the therapeutic substance into the tubular part 31 together with the liquid by causing the negative pressure in the tubular part 31 by the syringe unit 22 when the therapeutic substance is stored therein, and is the space for pushing out the therapeutic substance to outside of the tubular part 31 together with the liquid by causing the positive pressure to act in the tubular part 31 by the syringe unit 22 when t

Abstract: A system for delivery of radiation to a target portion of a native tissue is provided. The system includes a catheter having a main catheter body. The main catheter body includes an outer catheter surface and an inner catheter surface that defines a longitudinally oriented lumen. The lumen extends between longitudinally spaced proximal and distal catheter face surfaces extending laterally between the inner and outer catheter surfaces. A sheath covers at least a portion of the outer catheter surface. The sheath includes a tapered portion protruding substantially longitudinally distally from a portion of the distal catheter face surface. A plurality of tubes extends through the lumen towards the distal catheter face surface. Each tube of the plurality of tubes is configured to selectively guide exposure of a radiation source to the target portion of the native tissue.

Abstract: An ultrasound calibration phantom comprises a portion including at least one fiducial structure having a selected geometric arrangement; a portion adapted for mechanical coupling of the ultrasound calibration phantom to a transrectal ultrasound (TRUS) stepper; and a guide for at least one surgical instrument, the guide being mechanically coupled to the fiducial structure and/or to the TRUS stepper at a selected pose relative to the fiducial structure. A calibration method uses the calibration phantom and provides automatic, intraoperative calibration of ultrasound imaging systems. The invention is useful in ultrasound-guided clinical procedures.

Abstract: A filter delivery device for implanting a vessel filter within a blood vessel of a patient's body. The filter delivery device includes a mechanism for preventing hooks and/or legs on a vessel filter from entangling with each other while the vessel filter is loaded within the delivery device. In one variation, the filter delivery device includes a delivery catheter with grooves at the distal end lumen opening. When a vessel filter with radially expanding legs is compressed and inserted into the distal end of the delivery catheter, the hooks on the distal end of the legs are received and separated by the corresponding grooves on the delivery catheter. In another variation, a pusher rod, with a receptacle for receiving the hooks, is positioned within a delivery catheter to prevent the entanglement of the hooks and/or legs of a filter loaded within the delivery catheter.

Abstract: A stranded brachytherapy product and methods of forming a stranded brachytherapy product. The methods includes the step of applying an adhesive to a carrier containing at least one brachytherapy seed so as to, upon curing of the adhesive, impart substantial rigidity to the carrier. Alternatively, the adhesive may be selectively applied so as to provide a deflectable brachytherapy product.

Abstract: A flexible or elastic brachytherapy strand that includes an imaging marker and/or a therapeutic, diagnostic or prophylactic agent such as a drug in a biocompatible carrier that can be delivered to a subject upon implantation into the subject through the bore of a brachytherapy implantation needle has been developed. Strands can be formed as chains or continuous arrays of seeds up to 50 centimeters or more, with or without spacer material, flaccid, rigid, or flexible.

Abstract: A system and method for estimating the current delivered to a patient during voltage-regulated electrical stimulation therapy by an implantable medical device includes calculating a total charge delivered and a peak current delivered and the time at which the peak current was delivered using a proxy for the current delivered to the patient and a component such as a current controlled oscillator, the output of which is proportional to the current proxy together with memory for storing values relating to the output proportional to the current proxy. The stored values also may be used to construct a waveform approximating the current delivered to the patient during a therapy of voltage-regulated stimulation. The system and method may be implemented in an active implantable medical device such as an implantable neurostimulator.

Abstract: An apparatus for supporting a brachytherapy includes at least one radiation device, at least one dose measuring device, and a processing unit. The at least one dose measuring device is configured to be introduced into a target area of an object under treatment which includes at least one target object and that is designed to measure radioactive radiation originating from the at least one radiation device, which is introduced into the target area of the object under treatment, and to provide the measured values by way of a device for transmission to the processing unit.

Abstract: Brachytherapy delivery devices and buttress elements are described herein, along with methods of assembling the brachytherapy devices and the buttress elements for co-delivery of the brachytherapy delivery devices and buttress elements are described herein.

Abstract: A robotic system for flexible needle steering under ultrasound imaging. A robot is used to steer the needle along a predetermined curved trajectory by maneuvering the needle base. The needle tip position is detected by an ultrasound sensor and the tracking error of the needle tip from a predetermined needle path is input to a controller which solves the inverse kinematic based on the needle position, and the needle and tissue properties. The control algorithm uses a novel method to detect the elastic properties of the tissue by analyzing tissue motion at the region in front of the needle tip. The inverse kinematic solution may be performed on a model of the needle as a flexible beam having laterally connected virtual springs to simulate lateral forces exerted by the tissue elasticity. The system is able to direct the needle to a target within the tissue while circumventing forbidden regions.

Abstract: An apparatus and method for in vivo and ex vivo control, detection and measurement of radiation in therapy, diagnostcs, and related applications accomplished through scintillating fiber detection. One example includes scintillating fibers placed along a delivery guide such as a catheter for measuring applied radiation levels during radiotherapy treatments, sensing locations of a radiation source, or providing feedback of sensed radiation. Another option is to place the fibers into a positioning device such as a balloon, or otherwise in the field of the radiation delivery. The scintillating fibers provide light output levels correlating to the levels of radiation striking the fibers and comparative measurement between fibers can be used for more extensive dose mapping. Adjustments to a radiation treatment may be made as needed based on actual and measured applied dosages as determined by the fiber detectors. Characteristics of a radiation source may also be measured using scintillating materials.

Abstract: A tool for extracting a pin from a substrate comprises a first lever arm with a body part having a cavity in which the free end of a pin can be received, and a second lever arm which can pivot relative to the first lever arm. A jaw component is provided within the body part which can be actuated from an unlocked position in which a pin within the jaw component can slide freely past the jaw component, and a locked position in which the pin is gripped by engagement of the jaw component with the side wall of the pin, and a support is provided which can slide relative to the body part, in a direction towards the substrate from which the pin is to be extracted. Initial movement of the first lever arm relative to the second lever arm causes the jaw component to be actuated from its unlocked position to its locked position so that an inserted pin is gripped by the jaw component.

Abstract: A flexible, multi-lumen brachytherapy device includes a plurality of loose lumens extend through a hub towards a single point of attachment at a distal rigid section. Because the lumens are attached at only a single distal location, the lumens are free to move axially and rotatably, thereby increasing the overall flexibility of the device to thereby decrease intermittent device movement while increasing patient comfort. A novel keyed stylet can be selectively inserted to increase the rigidity of the device as needed. The ability to dynamically modify the rigidity of the brachytherapy device provides a comprehensive brachytherapy solution that satisfies concerns of the patient, the surgeon and the radiologists.

Abstract: Applicators for HDR brachytherapy for topical skin treatment which employ multiple channels for radioisotope sources, oriented by the applicator generally parallel to each other and to a desired treatment area skin surface. These applicators provide good radiation exposure uniformity. Filtration of undesirable low energy radiation may be employed using an attached filter element. The applicators are particularly adapted for the treatment of squamous and basal cell skin cancers or other skin lesions. The applicators may provide two or more source guides in various sizes and shapes are described.

Abstract: Embodiments include a fiducial deployment system and method for use thereof. A fiducial may include one or more protuberances configured to engage one or more slots in a needle of the system. The needle may be configured to deliver a plurality of fiducials to a target location in serial fashion, one at a time. In certain embodiments, echogenic placement of fiducials may present certain advantages.

Abstract: An apparatus and method for in vivo and ex vivo control, detection and measurement of radiation in therapy, diagnostics, and related applications accomplished through scintillating fiber detection. One example includes scintillating fibers placed along a delivery guide such as a catheter for measuring applied radiation levels during radiotherapy treatments, sensing locations of a radiation source, or providing feedback of sensed radiation. Another option is to place the fibers into a positioning device such as a balloon, or otherwise in the field of the radiation delivery. The scintillating fibers provide light output levels correlating to the levels of radiation striking the fibers and comparative measurement between fibers can be used for more extensive dose mapping. Adjustments to a radiation treatment may be made as needed based on actual and measured applied dosages as determined by the fiber detectors. Characteristics of a radiation source may also be measured using scintillating materials.

Abstract: The invention relates to a brachytherapy apparatus (1) for applying a brachytherapy to a living object. The brachytherapy apparatus comprises a planning unit (14) for determining a placing plan defining placing positions and placing times for one or several radiation sources within the living object and close to a target region. The placing plan is determined such that the placing times are within a treatment time window determined by a treatment time window determination unit (13), wherein within the treatment time window a change of a spatial parameter of the living object caused by swelling is minimized. An adverse influence on the brachytherapy due to swelling can thereby be minimized, which improves the quality of the brachytherapy.

Abstract: The invention relates to a real time radiation treatment planning system for use in effecting radiation therapy of a pre-selected anatomical portion of an animal body using hollow needles. According to embodiments of the invention, the system may include a processing means processing means-configured to perform a three-dimensional imaging algorithm and a three-dimensional image segmentation algorithm, with respect to one or more specific organs within the pre-selected anatomical portion and with respect to the needles, for converting the image data obtained with an imaging means into a three-dimensional image of the anatomical portion, using at least one single or multi-objective anatomy-based genetic optimization algorithm.

Abstract: Brachytherapy radioisotope carrier systems and methodology for providing real-time customized brachytherapy treatment to subjects with tumors difficult to control using conventional radiation therapy techniques. The invention generally relates to devices, methods and kits for providing customized radionuclide treatments, to help cure, slow progression or regrowth, or ameliorate the symptoms associated with tumors.

Abstract: There is provided herein a brachytherapy delivery system for the internal delivery and positioning of therapeutic agent, most particularly, a discrete radiation emitting particulate, within or in proximity to a vertebral or other bony tumor. The system comprises an elongated bone cannula having a proximal and a distal end, the distal end being suitable for disposition within bone. The bone cannula further comprises a bore disposed longitudinally therethrough suitable to axially and slidably receive an elongated and cannulated therapy delivery apparatus through which the therapeutic agent is delivered.

Abstract: A device for loading and customizing brachytherapy carriers based on the principles of optimizing a more precise and predictable dosimetry, and adaptable to the geometric challenges of a tumor bed in a real-time setting. The present invention relates to a specialized loading device designed to enable a medical team to create a radionuclide carrier for each patient and tumor reliably, reproducibly and efficiently.

Abstract: A spacer for use in brachytherapy, and radiotherapy, is formed of an encapsulating material in a generally cylindrical or elongated shape. Regions are formed within the spacer and retaining therapeutic loads, such as radiation sources and/or pharmaceutical therapeutic loads, and/or other substances to treat a patient, such as drug liquids, powder or particles (e.g., microparticles or nanoparticles), with the particles or powders combined with binders, such as polyacrylamide, that are selected to gradually disperse the powder or particles at a desired rate. Such regions can be formed at various locations within the spacer, and can have various shapes depending on the particular design and intended usage. The outer surface of the encapsulating material can optionally include one or more fins, ribs or other physical protuberances or features that improve the fixity of the spacer when implanted within a patient's body.

Abstract: Brachytherapy radioisotope carrier systems and methodology for providing real-time customized brachytherapy treatment to subjects with tumors difficult to control using conventional radiation therapy techniques. The invention generally relates to devices, methods and kits for providing customized radionuclide treatments, to help cure, slow progression or regrowth, or ameliorate the symptoms associated with tumors.

Abstract: Embodiments include a fiducial deployment system including a needle and at least two adjacent and releasably-engaged fiducials retained within a lumen of the needle by engagement with each other and/or by engagement with a pusher element. A fiducial may include one or more mechanical engagement structures that interengage with and/or are rupturably attached to one or more adjacent fiducials. The needle, which may include echogenic enhancements, may be configured to deliver a plurality of fiducials to a target location in serial fashion, one at a time. A variety of releasably-engaged fiducials are disclosed, as are methods for use.

Abstract: A lightweight, portable, interchangeable and effective overlay plate that will increase the efficiency of brachytherapy radiation treatment and reduce the duration of the radiation exposure during the radioactive seed insertion and positioning in brachytherapy. The overlay plate has a limited number of apertures specific to the treatment of a particular patient and is attached to the matrix used to position and guide the needles with the radioactive seeds. The apertures of the overlay plate may further be truncated-cone-shaped, with the narrow ends aligned with corresponding apertures in the matrix and the flared ends facing the user. The overlay plate minimizes the radiation exposure as much as reasonably possible because any amount of radiation exposure carries a risk to the exposed individual, and the overlay plate may also be manufactured from radiation-protective material to further minimize the radiation exposure.

Abstract: A lightweight, portable, interchangeable and effective shield that will protect from radiation during the radioactive seed insertion and positioning in brachytherapy. The shield is attached to the matrix used to position and guide the needles with the radioactive seeds. The shield minimizes the radiation exposure as much as reasonably possible because any amount of radiation exposure carries a risk to the exposed individual.

Abstract: An applicator for use in radiation therapy comprises: a main body for holding a radiation source, wherein the main body has a cavity extending along a main axis of the main body in the interior thereof; and an absorption body which is movably connected to the main body and influences the radiation emerging from the radiation source in such a way that a preferred radiation direction is defined, wherein the absorption body is movable with respect to the main body in such a way that the preferred radiation direction can be tilted into a plurality of different positions relative to the main axis of the main body.

Abstract: An apparatus for providing at least one treatment to at least one tissue having a first structural arrangement configured to expand a first portion at a distal end of the apparatus, a second structural arrangement configured to expand a second portion at the distal end and at least one lumen associated with at least one of the first structural arrangement and/or the second structural arrangement. The first structural arrangement and/or the second structural arrangement can be configured to position the at least one lumen at a particular position with respect to the tissue. A tip is configured to aid in the insertion of the apparatus into the tissue(s).

Abstract: Brachytherapy treatment apparatus are provided that include an elongate body including a core member and an outer member surrounding and movable relative to the core member. One or more helical catheters are provided on a distal portion of the elongate body, e.g., including distal ends coupled to the core member and proximal ends coupled to the outer member. The outer member is movable relative to the core member, e.g., axially and/or rotationally, to direct the helical catheters between a collapsed configuration for introduction through a tissue tract to a target location, e.g., a lumpectomy cavity, and an expanded configuration. Each helical catheter includes a lumen, and, after expansion to the expanded configuration, a source of radiation may be introduced along the helical catheters and/or a lumen of the core member for delivering radiation to the target location. Optionally, the apparatus may include a balloon surrounding or within the helical members.

Abstract: A cartridge may include a housing configured to contain a plurality of like items and a track inside the housing. The track extends in a first direction, and a plunger may be slidable along the track in the first direction and configured to urge the items toward a first end of the housing. The cartridge may include a gate attached to the housing. The gate may be movable between a first position preventing the items from being removed from the housing and a second position allowing one of the items to be removed from the housing. The gate may be configured to remove the one item from being urged by the plunger.

Abstract: A medical device according to the invention for insertion into a human and/or animal body comprises an elongated tubular lead probe including a proximal end portion and a distal end portion, an opening which opens into a lumen extending in the axial direction being formed on the proximal end of the lead probe, and the distal end of the lead probe being closed. The medical device further comprises an elongated core which is constructed in such a manner that it can be inserted into the lead probe and removed again via the lumen, and the core is made from non-metallic filaments and a matrix material.

Abstract: In part, the invention relates to fiduciary markers suitable for affixing to a patient that are detectable with respect an imaging modality such as MRI and methods of making the same. The markers include a paramagnetic material disposed therein that generates a distinguishable signal relative to a patient or other biological sample of interest during an imaging data collection session. Further, the markers demonstrate desirable signal to noise ratios across two or more MRI data collection procedures in one embodiment. The length of the markers is also adjustable by, for example, cutting or tearing a substrate upon which a substantially fluid-free region straddles a specified separation position on the substrate.

Abstract: An in-vivo dose detector (41) for an HDR brachytherapy system (1; 31), wherein the detector is insertable into and movable through a catheter (15), and comprises a sensor (53) operable to detect radiation from a source (52) used to irradiate a tissue to be treated (9) in the course of an HDR brachytherapy treatment. A brachytherapy system and a method of dose monitoring are also disclosed.

Abstract: Disclosed is a device for contact radiotherapy, comprising a set of applicators, wherein each applicator comprises a hollow spherical head, with different diameters, the external surface of which is able to be in contact with a cavity of a living tissue and the internal surface of which defines an internal space able to receive a source of x-rays, with at least one area of the head is intended to have x-rays pass through it, and the thickness of said area depends on the diameter of the head configured so that the dose of x-rays produced at the external surface is between 18 and 22 gray. Also disclosed is a system for contact radiotherapy comprising said device. The disclosed device and system apply particularly to per-operative radiotherapy, in that the irradiation is produced in contact with the ablation bed of the tumour, in particular in the breast, during the operation.

Abstract: A spacer for use in brachytherapy, and radiotherapy, is formed of an encapsulating material in a generally cylindrical or elongated shape. Regions are formed within the spacer and retaining therapeutic loads, such as radiation sources and/or pharmaceutical therapeutic loads, and/or any other substances to treat a patient, such as drug liquids, powder or particles (e.g., microparticles or nanoparticles), with the particles or powders combined with binders, such as polyacrylamide, that are selected to gradually disperse the powder or particles at a desired rate. Such regions can be formed at various locations within the spacer, and can have various shapes depending on the particular design and intended usage. The outer surface of the encapsulating material can optionally include one or more fins, ribs or other physical protuberances or features that improve the fixity of the spacer when implanted within a patient's body.

Abstract: Apparatus for delivering brachytherapy to a target tissue region includes an elongate body including a proximal end, a distal end sized for introduction into a tissue tract and carrying a plurality of elongate members including pathways for receiving a source of radiation. The elongate members are movable between collapsed and expanded configurations. During use, a tract is created through tissue, and the elongate body carrying the elongate members is advanced through the tract into a target location with the elongate members in the collapsed configuration. The elongate members are directed to the expanded configuration at the target location, and radiation is delivered to treat tissue at the target location, e.g., by introducing one or more radiation sources along the pathways. The apparatus may include features to prevent overexpansion of the elongate members and/or to facilitate rapid collapse of the elongate members.

Abstract: An embodiment of the present disclosure is directed to a brachytherapy source assembly including a guiding wire and a brachytherapy capsule located at a distal end of the guiding wire. The capsule includes a chamber defined by a wall for holding a radioactive source. At least a portion of an exterior surface of the wall of the capsule includes at least one of a friction-reducing coating, a wear-resistant coating, and a wear-indication coating a coating.

Abstract: A mechanism to facilitate the insertion of radioactive sources/source strands into soft tissue, such as breast tissue, and a method that utilizes this mechanism with the goal of improving the reproducibility of the procedure and ensuring that the sources are reliably and consistently inserted in an exact position per a patient prescription treatment plan from patient to patient as well as improve the ease-of-use of the device and procedure are provided.

Abstract: An applicator is provided, for manipulating one or more catheters carrying a radiation generating device, for delivering a radiation field to a target, the applicator having a proximal end and a distal end. The applicator includes: a spring mechanism; at least one catheter grasper for grasping one or more catheters carrying a radiation generating material, the catheter grasper being attached to the spring mechanism; and a sheath, for covering at least a portion the spring mechanism. The spring mechanism is designed for being retracted within the sheath, in a closed configuration of the applicator. The spring mechanism is designed for being released into a predetermined arrangement when moved out of a distal end of the sheath, in an open configuration of the applicator. The applicator is designed to be repeatedly switched between the closed configuration and the open configuration.