Abstract: A surgical instrument includes a pressure sensitive element that contacts a patient's tissue during surgery. The pressure sensitive element sends a signal to a computer processor that compares the signal to a known pressure being applied to the surgical instrument to calculate the rigidity of the tissue. The processor then delivers that information to the operating surgeon. The rigidity of the tissue may correspond to an audible tone, visual indicator or tactile feedback.

Abstract: A method for designing a patient specific orthopaedic device intended for an osteoarticular structure of a patient, based on at least two two-dimensional radiographic images of the osteoarticular structure taken respectively in two offset image-taking directions, comprising the following steps: b) locating anatomical points on the radiographic images; c) determining at least one three-dimensional geometrical feature of the patient by matching the anatomical points b) located at step b); d) determining at least one three-dimensional size parameter of the orthopaedic device based on the geometrical feature of the patient determined at step c).

Abstract: The present invention relates to a method of calculating a surgical intervention plan. Based on surface data of the patient, a surface representation of a part of the patient's body is created. From a database, a plurality of surgical methods may be selected and the geometrical parameters of a surgical plan can be adapted based on each individual surgical method. Therefore, the surgeon may easily select, which of the surgical method is appropriate for the planned surgical intervention. Furthermore, the surgical intervention plan which has been adapted according to the finally selected surgical method may then be projected onto the skin of the patient such that a drawing of the incision lines is facilitated. Furthermore, the use of a remotely activatable pen based on the current position of the pen and based on the finally selected surgical plan is presented.

Abstract: Systems and methods for positioning a cut guide using navigation-based techniques are discussed. For example, a system for use in an orthopedic surgery on a target bone can comprise a cut guide adjustably positionable onto the target bone via two or more coupling receptacles created on the target bone. The coupling receptacles can include one or more guide members and a plurality of landing members. The system also includes an input interface that can receive a target bone representation, and a model receiver module that can receive a generic post-coupling bone model. The target bone representation can include a data set representing two or more landing sites of the target bone, and the generic post-coupling bone model can include a data set representing a bone having two or more coupling receptacles each sized, shaped or otherwise configured to receive and secure the respective coupling feature of the landing members.

Abstract: A method of generating a correction plan for correcting a deformed bone includes inputting to a computer system a first image of the deformed bone in a first plane and inputting to the computer system a second image of the deformed bone in a second plane. Image processing techniques are employed to identify a plurality of anatomical landmarks of the deformed bone in the first image. The first image of the deformed bone is displayed on a display device. A graphical of the deformed bone is autonomously generated and graphically overlaid on the first image of the deformed bone on the display device, the graphical template including a plurality of lines, each line connected at each end to a landmark point corresponding to one of the anatomical landmarks. A model of the deformed bone may be autonomously generated based on the graphical template.

Abstract: A device and method is provided for a trackable suction tool for surgical use. The tracked suction tool includes a tubular handle with a main tube and an entrance tube extending from the main tube, a flattened section of the main tube with a suction-regulating orifice, a tip connected to the main tube distal end and a tracking mechanism connected to a handle proximal end. A method is provided for tracking the position of a tracked suction device including attaching a tip to a handle in one of a plurality of fixed positions, attaching a tracking mechanism to the handle in one of a plurality of fixed positions, calibrating the position of the tip with a positional tracking system using the tracking mechanism, positioning the tracking markers in view of the positional tracking system and tracking a position of the distal end of the tip of the suction device.

Abstract: Systems and methods for treatment of a spine of a patient. The system includes a treatment device comprising a probe tip at a distal end of the device. The system further includes a display device configured to display information associated with the treatment. The system further includes at least one computing device in electrical communication with the display device and the treatment device. The memory of the computing device includes software for operating a GUI. The at least one computing device configured to display the GUI comprising a virtual representation of: a first skeletal structure; at least one of an organ and a muscle; and a nerve network. The device also configured to display a graphic along a portion of the neural pathways associated with a user selected vertebra of the vertebrae when the treatment device is actuated to deliver the treatment.

Abstract: The invention comprises a system and method that may help place or position a component, such as an acetabular cup or a femoral component, during surgery. An example system may iteratively register a plurality of two-dimensional projections from a three-dimensional model of a portion of a patient, the three-dimensional model being generated from a data set of imaging information obtained at a neutral position. An example system may further score each two-dimensional projection against an intra-operative image by calculating a spatial difference between corresponding points. A two-dimensional projection having a minimum score reflecting the smallest distance between the corresponding points may be identified.

Abstract: A surgical system includes a preload assembly in a surgical instrument surgical instrument manipulator that is under the control of a controller. The controller can automatically cause the preload assembly to engage and disengage a preload. A surgical apparatus includes a surgical instrument manipulator assembly and a sterile adapter assembly. The sterile adapter assembly is mounted in the distal face of the surgical instrument manipulator assembly. When the preload assembly configures the surgical instrument manipulator assembly to apply a preload force on the sterile adapter assembly, the sterile adapter assembly is removable from the distal face of the surgical instrument manipulator. The sterile adapter assembly includes a mechanical sterile adapter assembly removal lockout and a mechanical surgical instrument removal lockout.

Abstract: A controller in a computer-assisted teleoperated surgical system automatically moves a part of the system, in response to a user tapping the part, to facilitate draping of that part. This speeds the draping process and diminishes the likelihood that the sterile surgical drape is damaged or contaminated during the draping of that part of the system.

Abstract: Systems and methods for minimally invasive computer-assisted telesurgery are described. For example, this disclosure provides surgical instruments and instrument drive systems for computer-assisted tele-operated surgery that are structured and operated to negate the effects of cable stretch within the surgical instruments.

Abstract: A medical device system can include a surgical tool, and a one-way input, and a drive system operatively coupled to the surgical tool and the oneway input device. The drive system can be rotatable in a first direction to effectuate a first operation of the surgical tool, and rotatable in a second direction to effectuate a second the operation of the surgical tool. The one-way input device can be operable to rotate the rotatable drive system in the second direction but not the first direction.

Abstract: The present invention provides a minimally invasive surgical instrument with a terminal steerable mechanism, comprising an intervention device, a control device and one or more wires. The strip-shaped intervention device sequentially includes a main section, a flexible section and an operation section from the top to the end. The control device includes a sphere with a preset rotational degree of freedom, and an operating lever connected to the sphere. Said one or more wires are extended along the main section of the intervention device. Here, the second ends of said at least one or more wires are connected to the flexible section or the operation section of the intervention device, and the first ends thereof are connected to at least a part of the control device.

Abstract: A coupler assembly for selective connection of a surgical instrument to a robotic arm is provided. The coupler assembly includes a stationary hub and a rotation hub. The stationary hub has a first mating feature and is secured to a first one of the surgical instrument and the robotic arm. The rotation hub includes a support member and rotation member mounted on the support member. The support member is secured to a second one of the surgical instrument and the robotic arm. The rotation member is rotatable relative to the support member between a first state and a second state. The rotation member has a second mating feature that releasably couples to the first mating feature of the stationary hub as the rotation member rotates relative to the stationary hub.

Abstract: A shaft for a surgical instrument comprises an outer tube having a proximal end and a distal end, a central lumen extending through the outer tube, and a plurality of stiffening rods positioned around the central lumen. The plurality of stiffening rods may comprise a nonconductive material. The shaft may form part of an electrosurgical instrument. In another embodiment, a surgical instrument may comprise an end effector and a shaft having an outer tube having a proximal end and a distal end, a drive rod, and at least four stiffening rods positioned around the drive rod, each stiffening rod being positioned substantially immediately adjacent to the drive rod. The axial stiffness of the shaft increases incrementally during actuation of the end effector.

Abstract: A control unit for a medical device that includes a palm interface engageable by a palm of a hand and a restraint capable of elastically deforming to apply a restraining force to the dorsum of the hand and a finger interface engageable by one or more fingers of said hand.

Abstract: A surgical tool includes a drive housing, a drive input and input shaft rotatably mounted to the drive housing, and a drive assembly mounted to the input shaft and including an upper capstan rotatably mounted to the input shaft with a first one-way bearing, and a lower capstan rotatably mounted to the input shaft with a second one-way bearing. First and second drive cables are coupled to the upper and lower capstans and extend to an end effector of the surgical tool. Rotating the input shaft in a first angular direction rotationally disengages the lower capstan from the input shaft and drives the upper capstan in the first angular direction, and rotating the input shaft in a second angular direction rotationally disengages the upper capstan from the input shaft and drives the lower capstan in the second angular direction.

Abstract: Disclosed is a surgical drape configured to selectively allow or block a patient's view of the surgical field, as is desired in Caesarean section operations. Generally, the drape includes a main sheet, a substantially transparent sheet attached to the main sheet proximal the patient's head, and a substantially opaque screen attached to the patient-facing side of the substantially transparent sheet. This substantially opaque screen occludes the patient's visual access through the substantially transparent sheet but may be at least partially removed to permit the patient viewing access through the substantially transparent sheet towards the area of the surgery, without compromising the sterility of the surgical field. Desirably, the drape is provided with an adhesive strip disposed on the sheet or screen to permit reconnection to thereby again occlude the patient's view through the sheet.

Abstract: A surgical instrument includes a body, an ultrasonic blade, a clamp arm assembly, and a detent assembly. The clamp arm assembly includes a clamp arm pivotably coupled with the body at a pivot assembly. The clamp arm is operable to compress tissue against the ultrasonic blade. The detent assembly is configured to provide tactile resistance to pivotal movement of the clamp arm relative to the body beyond a predefined pivot angle. The detent assembly is configured to permit pivotal movement of the clamp arm relative to the body beyond a predefined pivot angle upon application of a force sufficient to overcome the tactile resistance.

Abstract: The aim of the invention is to create a device for arranging medical targeting devices, markers, probes or surgical instruments for image-assisted, minimally invasive operations, which has a simple construction and is easy to use. Said device according to the invention has at least one carrier element (1) that can be positioned preferably with an adhesive layer on the surface of the body, and a fine-positioning unit (2). It is proposed that the carrier element (1) comprises at least one interlocking mount (3) for the fine-positioning unit (2) which has a matching complementary shape (3c).

Abstract: Provided is an image processing device including a matching unit that performs matching processing between a predetermined pattern on a surface of a 3D model of a biological tissue including an operating site generated on the basis of a preoperative diagnosis image and a predetermined pattern on a surface of the biological tissue included in a captured image during surgery, a shift amount estimation unit that estimates an amount of deformation from a preoperative state of the biological tissue on the basis of a result of the matching processing and information regarding a three-dimensional position of a photographing region which is a region photographed during surgery on the surface of the biological tissue, and a 3D model update unit that updates the 3D model generated before surgery on the basis of the estimated amount of deformation of the biological tissue.

Abstract: Embodiments of an actuating device for actuating a needle cartridge and puncturing an epidermis with controlled depth. The actuating device includes a motor housed in a motor housing, an actuating rod driven by the motor and configured to actuate in a reciprocating motion, and an adjustment mechanism. The actuating rod is housed in a rod housing, the rod housing forming a device aperture configured to receive a needle cartridge and to attach to the needle cartridge. The adjustment mechanism interfaces with the rod housing and is configured to adjust a position of the rod housing relative to the motor housing while not rotating the rod housing relative to the motor housing.

Abstract: A method of virtually designing a customized healing abutment and a drill guide for a patient, where the method includes: obtaining a CT scan including at least part of the patient's jaw bone; virtually placing at least one implant relative to the jaw bone of the CT scan, such that a planned implant placement is defined; virtually designing: a drill guide for guiding the surgical drilling of a bore for the implant into the patient's jaw bone at the planned implant placement; and a customized healing abutment configured for shaping the soft tissue according to a target profile when arranged in the implant; where the design of the drill guide and of the customized healing abutment is at least partly based on the CT scan and on the planned implant placement.

Abstract: Systems and methods of simulating dental treatments are disclosed. A method may include capturing a first 2D image of a patient's face, including the patient's teeth, building a parametric 3D model of the patient's teeth based on the 2D image, developing a simulated outcome of a dental treatment of the patient's teeth by rendering the 3D model with the patient's teeth in one or more positions and/or orientations corresponding to the treatment goals of the dental treatment plan, and rendering a second 2D image of the patient's face with teeth according to a simulated outcome of the dental treatment plan. As noted herein, the dental treatment plan may include orthodontic and/or restorative elements. The simulated outcome may correspond to estimated outcomes and/or intended outcomes of the dental treatment plan.

Abstract: Provided herein are orthodontic systems and methods for automatically segmenting a person's teeth. Systems, methods and processes are provided to properly segment the teeth of a person's teeth from an image of the person's face showing at least some of the person's teeth (e.g., dental arch). Methods and systems are provided to automatically detect dental edges after a dental scan. Also described herein are methods and systems for generating a simulated image of the person's face from the final segmentation of the person's teeth in which the segmented teeth have been moved from their original position, including a new position based on an orthodontic treatment plan.

Abstract: An orthodontic appliance is disclosed that integrates an arch expander with a first segment and a second segment. The first and second segments are disposed on opposite sides of a midline of a dentition of an orthodontic patient. Both the first segment and the second segment are disposed over multiple teeth on the respective side of the midline, with a gap existing proceeding along the dentition between anterior-most portions of the first segment and the second segment. The arch expander is integrated with the first and second segments to exert an anteriorly-disposed expansion force on the patient's dentition through the first and second segments, for instance where the posterior-most location where these expansion forces are exerted corresponds with a first bicuspid on each side of a permanent the dentition.

Abstract: Methods and devices are disclosed, by use of which an external fiducial element positioned in the mouth serves as a geometrical constraint on oral arch geometry. In some embodiments, the fiducial element is an oral insert which reaches to a plurality of oral arch regions to present surface details which are in well-defined distance and/or angular relationships to one another. These spatial relationships optionally comprise a spatial frame of reference which serves to constrain reconstruction of the geometry of one or both of the oral arches, for example reconstruction from a collection of digitally registered, partially-overlapping scans made along the oral arch.

Abstract: A teeth cleaning travel kit includes toothbrushing mouthpiece that has two inverted channels dimensioned to receive upper and lower bites of dental arches of a user, the channels being integral with one another. Teeth-cleaning bristles inwardly project within the two inverted channels to bear inwardly against teeth and gums of the user, wherein the channels and teeth-cleaning bristles are configured such that mastication produces relative brushing movement of the teeth-cleaning bristles over the teeth and gums. An oral hygiene promoting product is attached to one of the two inverted channels and the teeth-cleaning bristles that is released by action of the user's mouth. The teeth cleaning travel kit also includes a vessel that contains a rinsing fluid and kit packaging that contains the toothbrushing mouthpiece and vessel.

Abstract: There is provided a method for controlling a flow of intestinal contents in the intestinal passageway of a patient's intestines. The method comprises gently constricting (i.e., without substantially hampering the blood circulation in the intestinal tissue wall) at least one portion of the intestinal tissue wall to influence the flow in the intestinal passageway, and stimulating the constricted wall portion to cause contraction of the wall portion to further influence the flow in the intestinal passageway. The method can be used for restricting or stopping the flow in the intestinal passageway, or for actively moving the fluid in the intestinal passageway, with a low risk of injuring the intestines.

Abstract: Devices, systems and methods for filtering embolic particles that may be generated from a medical procedure including protection of the major branching vessels from the aorta, and catches and filters emboli that may be generated during the TAVR procedure. The filter devices disclosed herein form an improved seal against the vessel wall that is activated by flowing blood. Devices described herein also allow for the closing of the ends of the filter device after capture of emboli, providing further security against accidental loss of emboli post capture.

Abstract: Vascular filtering devices and methods for their use are disclosed. In some embodiments, the vascular filtering devices include an elongate member having an unsupported membrane bag portion attached thereto. The membrane may be porous in some examples. Multiple elongate extensions may also extend from the membrane, and may extend along the elongate member, such as to a proximal region of the elongate member. The unsupported membrane bag portion may be configured to inflate or otherwise radially expand away from the elongate member as a result of blood flowing through the vessel within which the vascular filtering device is positioned.

Abstract: An intraluminal device adapted to be positioned in a lumen that experiences peristalsis and method of fixation of an intraluminal device in the lumen, includes a wall configured to the size and shape of a portion of the lumen and at least one core. The at least one core is removably connected with a portion of the device wall. The at least one core is configured to be positioned against the lumen when the wall is positioned in the lumen. In this manner tissue envelopes the core during implantation of the intraluminal device. The at least one core is configured to be axially removable in situ from the tissue enveloping the core after the device has been deployed by disconnecting the core from the portion of the wall in order to explant the intraluminal device from lumen.

Abstract: According to exemplary embodiments of the present disclosure, devices, systems, and methods for pyloric occlusion in an endoscopic procedure may include a first flange and a second flange connected to the first flange by a saddle region having a lumen. The second flange may be proximal to the first flange. The pyloric occlusion device may further include a closure element. The closure element may be configured to occlude a flow of material through the lumen, including across the pylorus when deployed. The closure element may be a closure of the lumen by rotation of one of the first or second flanges about the saddle region relative to the other of the first or second flange.

Abstract: A venous anchor device operably coupled by graft material to form an anastomotic connector is provided. The venous anchor device includes a tubular main body having a metal frame structure and including a distal end and a proximal end, the distal end including a plurality of barbs thereon wherein said distal end has an outer diameter greater than the proximal end. The venous anchor device is fluidly connected by a graft to form an anastomotic connector.

Abstract: The present invention is an anatomic system which uses the principle of applying higher elastic tonus than the rest tonus of the agonist muscles to provide the function of the antagonist muscles, and which is designed in a simplest way to provide the said purpose and which can be integrated to the body. The static mechanism of the invention is an elastic mechanism which applies a continuous stable tension in order to keep the joints open. The tension of the mechanism is calibrated by increasing or decreasing the amount of the liquid in a chamber which has flexible and elastic walls up to a certain via a port. In the dynamic mechanism of the invention, the tension applied by the elastic mechanism can be changed according to the motion the patient wants to perform.

Abstract: Disclosed herein are methods and devices for securing soft tissue to a rigid material such as bone. A tissue anchoring device is described that comprises an anchor body and a spreader such that tissue may be captured or compressed between outside surfaces on the anchor and inside surfaces of a bone tunnel to secure the tissue within the tunnel. Methods are described that enable use of the bone anchoring device to secure a tissue graft into the tibial and femoral bones during anterior cruciate ligament (“ACL”) reconstruction.

Abstract: A bone anchor configured for use in anchoring an implanting portion to an anchor point. A bone anchor can be of particular use in anchoring soft tissue to a bone. A bone anchor can have a wire loop and a suture. The wire loop of the bone anchor can be configured to capture a suture and to pull a portion of the suture through a hole in the anchor body aiding in anchoring an item, such as tissue to a bone.

Abstract: Provided is an intraocular lens having a novel structure with high utility which is easy to adapt to patients, and can improve quality of vision (QOV). In an intraocular lens, an optical characteristic is set rotationally symmetric around an optical axis, and a spherical aberration of a size corresponding to a coma aberration remaining in a patient's eye after extraction of a human lens of the eye is set.

Abstract: The invention is directed to a cassette for accommodating an intraocular lens. The cassette defines a longitudinal axis and includes a base part. Pivotable cover flaps are arranged on the base part so as to be pivotable about the longitudinal axis from a base position to a closed position. The cover flaps are curved at least in selected regions thereof and are configured to be autonomously intrinsically bendable in a defined manner when the cover flaps are moved from the base position to the closed position.

Abstract: Aspects of the disclosure relate to prosthetic valves having a frame, a frame cover, and a leaflet construct. Some aspects are directed to a diametric taper for the prosthetic valve for achieving enhanced performance of the prosthetic valve under operational conditions, enhanced compressibility and delivery characteristics, and other additional or alternative advantages. Other aspects are directed toward unique assembly and attachment methods for securing leaflet constructs to support structures. Other aspects are directed toward features for interacting with transcatheter delivery systems. Still other aspects are directed to such apparatuses, systems, and methods for valve replacement, such as cardiac valve replacement.

Abstract: A prosthetic heart valve includes a frame, a valvular structure coupled to the frame, and a sealing member coupled to the frame. The frame has inflow and outflow ends and a lumen extending therebetween. The frame includes struts that form cells, and the cells are arranged in three rows. The frame is radially expandable from a collapsed state to an expanded state. The valvular structure includes a plurality of leaflets configured to allow blood flow through the lumen of the frame from the inflow end to the outflow end and to block blood flow through the lumen of the frame from the outflow end to the inflow end. The sealing skirt extends from an intermediate location of the frame disposed between the inflow and outflow ends to the inflow end of the frame. The sealing skirt covers two rows of cells to block blood flow through the cells.

Abstract: A delivery system for use with a prosthetic heart valve having a stent frame to which a valve structure is attached, includes a shaft assembly including a distal end and a coupling structure disposed near the distal end and configured to be coupled to a distal end of the prosthetic heart valve. The system includes a sheath assembly defining a lumen sized to slidably receive the shaft assembly. The delivery system is configured to transition from a loaded state in which the sheath assembly encompasses the prosthetic heart valve to a deployed state in which the sheath assembly is withdrawn from the prosthetic heart valve. The coupling structure is configured to provide a controlled expansion or contraction of the distal end of the prosthetic heart valve based on longitudinal movement of the distal end of the shaft assembly.

Abstract: A method for replacing a first sheath, whose distal end is positioned inside a vessel and whose proximal end is positioned outside the skin of a patient, with a second sheath may involve inserting a dilator over a guidewire and into the first sheath until a distal end of the dilator and a distal end of the guidewire are positioned inside the vessel. The dilator may be hubless or include a removable hub. The method may further involve removing the first sheath, thereby leaving only the dilator and the guidewire in place. After removing the first sheath, a second sheath may be passed over the dilator and the guidewire until the distal end of the second sheath is positioned inside the vessel. The method may further involve removing the dilator and the guidewire, leaving only the second sheath in place.

Abstract: Disclosed is a medical system for short time replacement and repair of a native valve, which comprises an artificial valve (502); and a device for collecting and arranging chordae and/or leaflets to hold and/or stabilize the artificial valve in a desired position, the device comprising: a unit for grasping a plurality of chordae and/or leaflets. The system and/or device allows for fast and easy replacement of a native valve, fast and easy positioning of a temporary artificial valve, and more time for medical personnel to make decisions, prepare and/or perform surgery/medical intervention.

Abstract: A valve prosthesis and a system for delivering a valve prosthesis are described herein. The system can include a core member and an engagement mechanism for releasably engaging a radially expandable valve anchor of the valve prosthesis along the core member. The engagement mechanism can include a pin assembly slidably coupled to the core member and a nose cone including a lock component slidably coupled along the core member to permit the valve anchor to disengage from the pin assembly.

Abstract: An anchor includes (a) an anchor head; and (b) a tissue-engaging member extending distally away from the anchor head until a distal tip of the tissue-engaging member, and configured to anchor the anchor to tissue. An anchor driver can include (a) a longitudinal shaft, having a flexible distal portion and a distal end; (b) a deployment element at the distal end of the shaft, reversibly lockable to the anchor head, and reversibly movable between (i) a locked state that retains locking between the deployment element and the anchor head, and (ii) an unlocked state that unlocks the deployment element from the anchor head; and (c) a tissue-piercing lance, reversibly movable between (i) an extended state in which the lance extends distally from the shaft past the distal tip of the anchor, and retains the deployment element in the locked state, and (ii) a retracted state in which the deployment element automatically moves into the unlocked state.

Abstract: Anchor delivery systems and methods for repairing a valve inside a body, such as a heart valve, may include a delivery catheter having a distal end comprised of two or more rotatably coupled knuckles. An anchor delivery mechanism is disposed distally of the two or more knuckles, and includes a first pincer arm having a distal end and a proximal end rotatably coupled to a distal end of the anchor delivery mechanism at a first connection point, and a second pincer arm having a distal end and a proximal end rotatably coupled to the distal end of the anchor delivery mechanism at a second connection point opposite the first connection point. In a closed position, the distal ends of the first and second pincer arms are positioned together. In an open position, the distal ends of the first and second pincer arms are rotated apart from each other.

Abstract: An exemplary valve repair system for repairing a native valve of a patient during a non-open heart procedure includes a delivery device and a valve repair device. The valve repair device includes a pair of gripping members that are configured to attach to the native valve of the patient. A gripper control mechanism is configured to independently engage and move each of the gripping members.

Abstract: The device (1) is intended to be positioned in a sealed introducer placed in a femoral vein in order to penetrate the left atrium (4) of the heart (3) by passing through the septal wall (5) thereof.

Abstract: According to some embodiments, a method of creating for creating a reverse tapered opening within tissue comprises creating a cylindrical opening within a targeted anatomical site of a subject using a first device and removing additional tissue from the sidewalls of the cylindrical opening using a cutting member to create a reverse tapered opening within the targeted anatomical site using a second device, wherein, once the reverse tapered opening is created, a diameter or other cross-sectional dimension of a bottom surface of the opening is larger than a diameter or other cross-sectional dimension of a top surface of the opening.