Patent Publication Number: US-2023157826-A1

Title: Universal low-profile intercranial assembly

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 16/203,357, entitled “UNIVERSAL LOW-PROFILE INTERCRANIAL ASSEMBLY,” filed Nov. 28, 2018, which is currently pending, which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/615,209, entitled “UNIVERSAL LOW-PROFILE INTERCRANIAL ASSEMBLY,” filed Jan. 9, 2018, both of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to neurosurgery, plastic surgery, craniofacial surgery, and intercranial devices. More particularly, the present invention relates to a universal low-profile intercranial device allowing for ready modification and replacement of functional components thereof for the purpose of functional neurosurgery. 
     2. Description of the Related Art 
     During cranioplasty procedures, diseased or damaged portions of the skull are safely removed and replaced, while the brain is exposed underneath without injury. However, a similar operation could also be done in areas of normal, healthy cranial bone—in instances where a neuromodulation device is needed for implantation but the contour and appearance is challenging (and normal skull bone would therefore be removed and left off permanently in exchange for “housing” the neuromodulation device with a cranial implant), such as in non-bearing scalp areas such as frontal or temporal regions. Similarly, following resection of diseased cranial bone (or normal bone in cosmetically-sensitive areas), such craniectomy defects are often reconstructed with custom craniofacial implants (CCIs)—as opposed to using generic, “off-the-shelf” materials. 
     Historically, however, cranioplasty patients were limited to receiving custom craniofacial implant-based reconstruction—for an ideal appearance and outcome—only to “second-stage” operations, in instances where pre-existing skull defects existed—so that the exact fit and design could be obtained via CT scan and implant design could be perfected accordingly. However, recent modifications to this approach by Gordon et al. (See, Berli J, et al., “Single-stage cranioplasty reconstruction with implants.” J Craniofac Surg 2016) have popularized the option of “single-stage cranioplasties”—by which a reconstructive surgeon, manually reshapes/resizes a previously-ordered, custom implant (with oversized dimensions) to fit perfectly into the skull defect—as opposed to using “off-the shelf” materials. Either way, for single-stage methods involving skull tumors or second-stage cranioplasties for pre-defined skull defects, the advent of computer-aided design/manufacturing (CAD/CAM), has provided surgeons with perfectly-shaped custom craniofacial implants designed and manufactured based in part on fine cut preoperative computed tomography (CT) scans and three-dimensional reconstruction (with or without stereolithographic models). 
     In fact, recent reports suggest that the use of custom craniofacial implants can improve cosmesis, decrease operative times, prevent scalp-related wound complications, and enhance patient satisfaction—and therefore, they serve as an ideal medium for reconstructing neurosurgery patients. Similarly, all custom craniofacial implants up until now have been used to replace abnormal bone having some form of disease, either of benign or malignant etiology. These customized skull implants may be termed “static custom craniofacial implants”—mainly because their main constant (i.e., unchanged purpose with respect to time) purpose encompasses strictly two benefits following placement—“brain protection” and “enhanced appearance”. In addition, they may be made out of a clear acrylic (or poly methyl methacrylate) substance for enhanced sub-implant visualization, which was previously described in Applicants&#39; own U.S. Provisional Patent Application Ser. No. 62/489,036, entitled “METHOD FOR PERFORMING SINGLE-STAGE CRANIOPLASTY RECONSTRUCTION WITH A CLEAR CUSTOM CRANIAL IMPLANT,” filed Apr. 24, 2017. Meanwhile, there are other “off-the-shelf” neurological implants that have functionality, such as delivering electrical impulses to interrupt seizure activity, but they are not customizable or designed ahead-of-time with ideal shape/size to protect the brain and restore cranial symmetry. Most of these so-called functional neurological implants fall into two categories: Deep Brain Stimulators (DBS) and Cortical Brain Stimulators (CBS). Modern day neurologic devices are confronted and challenged with high extrusion and infection risk (i.e., current flaws in modern day devices lead to high incidence of extrusion through skin thereby requiring premature explanation) approaching 50%. Similarly, battery-powered, low-profile devices for intercranial placement currently do not exist on the market. As such, the field of neurosurgery has been hampered and limited in many areas including examples like battery-powered neuromodulation cortical stimulation and delivery of neurological medicines. However, the world&#39;s first in-human experience with a battery-empowered neuromodulation device, encapsulated for the first time ever within a customized cranial implant, was recently reported in  Operative Neurosurgery  by Gordon et al in October 2017 (See, Gordon C R, First In-Human Experience with Complete Integration of Neuromodulation Device Within a Customized Cranial Implant. Oper Neurosurg 2017). 
     But with increasing experience and surgical complication rates exceedingly low, the custom craniofacial implants can also be modified in real-time for scenarios where more or less skull bone is removed and the skull defect dimensions do not match up perfectly to the pre-fabricated custom craniofacial implant (versus as originally envisioned, for example, as designed in a planning stage)—which is the scenario described within the aforementioned journal article. Or in a scenario where normal bone is to be removed simply to assure proper contour with neuromodulation implantation, one could use a pre-fabricated cutting guide for custom cranial implant placement. 
     Due to the recent reductions for time needed to design, fabricate and implant custom craniofacial implants, more cranioplasty procedures with alloplastic implants are being performed around the world than ever before. Accordingly, these recent developments in custom craniofacial implant sterility, shape design, and streamline production—together provide an opportunity that extends custom craniofacial implant-based cranioplasty beyond only patients who require replacement of pre-existing craniectomy defects. 
     SUMMARY OF THE INVENTION 
     It is, therefore, an object of the present invention to provide a universal low-profile intercranial assembly including a mounting plate and a low profile intercranial device. The low profile intercranial device includes a static cranial implant and an interdigitating functional neurosurgical implant. The low profile intercranial device is shaped and dimensioned for mounting to the mounting plate. 
     It is also an object of the present invention to provide a universal low-profile intercranial assembly wherein the mounting plate include a hollowed-out center aperture shaped and dimensioned for the ready placement and mounting of the low profile intercranial device therein. 
     It is another object of the present invention to provide a universal low-profile intercranial assembly wherein the static cranial implant includes a hollowed-out center cavity shaped and dimensioned for optimal anatomical placement of the functional neurosurgical implant within the confines of the center cavity. 
     It is a further object of the present invention to provide a universal low-profile intercranial assembly wherein the static cranial implant also includes structural elements accommodating features of the functional neurosurgical implant. 
     It is also an object of the present invention to provide a universal low-profile intercranial assembly wherein the mounting plate includes an outer convex first surface, an inner concave second surface, and a peripheral edge extending between the first surface and the second surface, as well as a center aperture accommodating the static cranial implant. 
     It is another object of the present invention to provide a universal low-profile intercranial assembly wherein the mounting plate is fabricated from clear and/or opaque PMMA (Poly(methyl methacrylate)), PEEK (Polyether ether ketone), PEKK (Polyetherketoneketone), porous polyethylene, titanium alloy, allograft, autograft, xenograft, and/or other tissue-engineered constructs. 
     It is a further object of the present invention to provide a universal low-profile intercranial assembly wherein the mounting plate has a thickness of 1 millimeter to 25 millimeters. 
     It is also an object of the present invention to provide a universal low-profile intercranial assembly wherein the static cranial implant includes an outer convex first surface, an inner concave second surface, and a peripheral edge extending between the first surface and the second surface, as well as a cavity accommodating the functional neurosurgical implant. 
     It is another object of the present invention to provide a universal low-profile intercranial assembly wherein the static cranial implant is fabricated from clear and/or opaque PMMA (Poly(methyl methacrylate)), PEEK (Polyether ether ketone), PEKK (Polyetherketoneketone), porous polyethylene, titanium alloy, allograft, autograft, xenograft, and/or various other tissue-engineered constructs. 
     It is a further object of the present invention to provide a universal low-profile intercranial assembly wherein the static cranial implant has a thickness of 1 millimeter to 25 millimeters. 
     It is also an object of the present invention to provide a universal low-profile intercranial assembly wherein the static cranial implant has a multiple-piece construction. 
     It is another object of the present invention to provide a universal low-profile intercranial assembly wherein the functional neurosurgical implant is used in the treatment of epilepsy, movement disorders, chronic pain, spasticity, cerebral palsy, multiple sclerosis, spinal cord injury, traumatic brain injury, attention-deficit/hyperactivity disorder, or autism. 
     It is a further object of the present invention to provide an intercranial assembly having a cranial implant including includes an outer first surface, an inner second surface, and a peripheral edge extending between the outer first surface and the inner second surface. The cranial implant includes topographical markings indicating thickness of the cranial implant and allowing a surgeon to readily and accurately appreciate the thickness of the cranial implant. 
     It is also an object of the present invention to provide an intercranial assembly wherein the topographical markings are composed of contour lines. 
     It is another object of the present invention to provide an intercranial assembly wherein the contour lines are produced by connecting points of equal thickness together to create a continuous line designating a specific thickness of the cranial implant at the contour line. 
     It is a further object of the present invention to provide an intercranial assembly wherein the contour lines are composed of specific colors designating a specific thickness. 
     It is also an object of the present invention to provide a universal low-profile intercranial assembly wherein the contour lines are annotated with numbers indicating the thickness of the cranial implant. 
     Other objects and advantages of the present invention will become apparent from the following detailed description when viewed in conjunction with the accompanying drawings, which set forth certain embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an exploded perspective view of a universal low-profile intercranial assembly with first and second low profile intercranial devices. 
         FIG.  2    is a perspective view of the universal low-profile intercranial assembly in accordance with a preferred embodiment of the present invention. 
         FIG.  3    is a sectional view of the universal low-profile intercranial assembly shown in  FIG.  2   . 
         FIG.  4    shows a patient obtaining a protocol CT scan prior to surgery. 
         FIG.  5    shows the CT scan is then converted to a digital data format useful in computer-assisted design/computer-assisted manufacture (CAD/CAM) manufacture procedures. 
         FIG.  6    is a computer screenshot showing a digitally rendered mounting plate and a digitally rendered base static cranial implant in accordance with the present invention. 
         FIG.  7    is a computer screenshot showing a digitally rendered functional neurosurgical implant in accordance with the present invention. 
         FIG.  8    is a computer screenshot showing a hybrid rendering in accordance with the present invention. 
         FIG.  9    is a computer screenshot showing an optimized hybrid rendering in accordance with the present invention. 
         FIG.  10    is a perspective view of an opaque customized static cranial implant in accordance with an alternate embodiment of the present invention. 
         FIG.  11    is a cross sectional view of a low-profile intercranial device showing a customized static cranial implant fabricated with embedded antibiotics in accordance with an alternate embodiment of the present invention. 
         FIG.  12    is a perspective view of a low-profile intercranial device including a customized static cranial implant with an embedded serial number in accordance with an alternate embodiment of the present invention. 
         FIG.  13    is a cross sectional view along the line  13 - 13  in  FIG.  12   . 
         FIG.  14    is a perspective view of a low-profile intercranial device including a customized static cranial implant with alignment lines in accordance with an alternate embodiment of the present invention. 
         FIG.  15    is a perspective view of a universal low-profile intercranial assembly including a mounting plate with relief recesses in accordance with an alternate embodiment of the present invention. 
         FIG.  16    is a perspective view of a low-profile intercranial device including a customized static cranial implant with laser cuts and laser markings in accordance with an alternate embodiment of the present invention. 
         FIG.  17    is an installed perspective view of the universal low-profile intercranial assembly shown in  FIG.  1   . 
         FIG.  18    is a sectional view of the universal low-profile intercranial assembly shown in  FIG.  17   . 
         FIG.  19    is a perspective view of a universal low-profile intercranial assembly in accordance with an alternate embodiment wherein the customized static cranial implant is of a two-piece construction. 
         FIG.  20    is an exploded view of the universal low-profile intercranial assembly shown in  FIG.  19   . 
         FIG.  21    is an installed perspective view of the universal low-profile intercranial assembly shown in  FIG.  19   . 
         FIG.  22    is a sectional view of the universal low-profile intercranial assembly shown in  FIG.  21   . 
         FIG.  23    is a perspective view of a 3-D printer that may be used in accordance with the present invention. 
         FIGS.  24 A and  24 B  are perspective views of the universal low-profile intercranial assembly in accordance with alternate embodiments of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The detailed embodiments of the present invention are disclosed herein. It should be understood, however, that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, the details disclosed herein are not to be interpreted as limiting, but merely as a basis for teaching one skilled in the art how to make and/or use the invention. 
     As used within this disclosure, the term “intercranial” means situated or occurring within the anatomical boundaries of the cranium itself—such that such devices are positioned within the anatomical dead space existing between the inner surface of the scalp and the outer surface of the dura (i.e. outside lining of the brain). As such, intercranial devices are those devices intended for positioning within the cranium itself as opposed to devices that may be positioned on or adjacent to the cranium or positioned along the interior of the cranium, for example, between the cerebral cortex and the interior surface of the cranium. With this in mind, intercranial devices such as those discussed below replace resected portions of the cranium due to abnormalities in the cranium, damage to the cranium, or other medically sufficient reasons for resecting positions of the cranium. 
     With reference to the various figures, a universal low-profile intercranial assembly  10  and a method for using the universal low-profile intercranial assembly  10  are disclosed. In addition to providing the universal low-profile intercranial assembly  10  and a method for using the universal low-profile intercranial device  10 , the present invention applies the manufacturing methods disclosed in commonly owned U.S. patent application Ser. No. 15/669,268, entitled “METHOD FOR MANUFACTURING A LOW-PROFILE INTERCRANIAL DEVICE AND THE LOW-PROFILE INTERCRANIAL DEVICE MANUFACTURED THEREBY,” filed Aug. 4, 2017 (which has published as U.S. Patent Application Publication No. 2018/0055640), which is incorporated herein by reference. That is, the universal low-profile intercranial assembly  10  and a method for using the universal low-profile intercranial assembly  10  take advantage of virtual design and maximal interdigitating of distinct cranial implants (that is, a low-profile static cranial implant and a functional neurosurgical implant in accordance with a preferred embodiment of the present invention). The term “interdigitating” is meant to refer to the interlocking of three distinct elements (that is, the mounting plate, the static cranial implant and the functional neurosurgical implant) such that the two distinct elements mesh together to ultimately define a single product. 
     As mentioned above, the universal low-profile intercranial assembly  10  is generally composed of mounting plate  12  into which a low profile intercranial device  14  composed of a static cranial implant  16  and an interdigitating functional neurosurgical implant  18  are mounted in accordance with the present invention. This combination of elements results in the present universal low-profile intercranial assembly  10  that provides a mechanism whereby various low profile intercranial devices  12  may be implanted as desired and needed based upon the progress of a patient undergoing cranial and/or brain based treatments. 
     More specifically, the universal low-profile intercranial assembly  10  of the present invention employs a CT (Computed Tomography) scan-based, virtual design session performed pre-operatively based on the brain-specific geographical location (as opposed to the standard method of using the skull-specific geographic location). As a result, the methodology employed in accordance with the present invention accommodates both brain and skull pathology in three-dimensional space, in all three axes, prior to surgery unlike ever before. 
     With this information, as well as knowledge regarding the dimensions of the functional neurosurgical implant  18 , the mounting plate  12  and/or the static cranial implant  16  are produced. The mounting plate  12  is augmented, reduced and/or modified to include a hollowed-out center aperture  20  shaped and dimensioned for the ready placement and mounting of the low profile intercranial device  14  therein. In this way, and as will appreciated based upon the following disclosure, the mounting plate  12  is specifically shaped and dimensioned for intercranial placement within the cranial defect while simultaneously providing a center aperture  20  into which a low profile intercranial device  14  may be readily mounted. Given that the center aperture  20  of the mounting plate  12  is of a known shape, which may be readily replicated and controlled, the shape of the low profile intercranial device  14  can be readily controlled to allow for immediate and exact placement of the low profile intercranial device  14  within the center aperture  20 . This allows for a first low profile intercranial device  14  to be implanted and used at a first stage of a patient&#39;s treatment and subsequently removed and replaced with a second low profile intercranial device  14 ′ at a second stage of the patient&#39;s treatment. 
     In addition to the mounting plate  12 , the static cranial implant  16  is similarly augmented, reduced and/or modified to include a hollowed-out center cavity  22  (it is appreciated multiple cavities may be employed where the functional neurosurgical implant(s)  18  being used dictates that the cavity  22  need not be directly in the center of the static cranial implant  16  but may be offset as dictated by the procedure being performed), as well as other structural elements  24  (for example, wire tunnel(s), pocket(s), etc.), shaped and dimensioned for optimal anatomical placement of the functional neurosurgical implant  18  that is ultimately positioned within the confines of the center cavity  22  (and other structural elements) of the static cranial implant  16  (i.e., like an empty shell case but with exact negative and positive enhancements to optimize anatomical positioning of both the static cranial implant and the functional neurosurgical implant). Depending upon the specifics of the functional neurosurgical implant  18  positioned within the center cavity  22  of the of static cranial implant  16 , various mechanical coupling mechanisms, for example, screws, plates, etc. (not shown), are used to ensure that the functional neurosurgical implant  18  is securely held in place. 
     As will be explained below in greater detail, the manufacture of the universal low-profile intercranial assembly  10  utilizes computer-based designs of the mounting plate  12 , the static cranial implant  16  and the functional neurosurgical implant  18 . The computer-based designs of the mounting plate  12 , static cranial implant  16  and the functional neurosurgical implant  18  are optimized during virtual design sessions incorporating neurosurgeon, plastic-reconstructive, or other surgeon input. The optimization process takes into account the three-dimensional, spatial relationship between the mounting plate  12 , the static cranial implant  16  and the functional neurosurgical implant  18  (amongst one another if there is more than one functional neurosurgical implant  18 ), as well as the underlying topographical relationship of the mounting plate  12 /static cranial implant  16 /functional neurosurgical implant  18  with the brain-skull anatomy and physiology of the specific patient for whom the universal low-profile intercranial assembly  10  is being customized and manufactured. Modification of a digitally rendered mounting plate  112   a  and digitally rendered base static cranial implant  116   a  with a final shape and contour before sterilization and surgical implantation in accordance with the present invention (to produce the final mounting plate  12  and the final static cranial implant  16 ) results in the present low-universal low profile intercranial assembly  10 . Through this process the spatial arrangement between the mounting plate  12 , the low-profile static cranial implant  16  and the functional neurosurgical implant  18  is improved when placed within the confines of one&#39;s skull. 
     Considering now the structural details of the mounting plate  12 , the mounting plate  12  includes an outer (commonly convex) first surface  26 , an inner (commonly concave) second surface  28 , and a peripheral edge  30  extending between the outer first surface  26  and the inner second surface  28 . The mounting plate  12  is shaped and dimensioned for engagement with the skull of the patient upon implantation in a manner well known to those skilled in the field of neurosurgical procedures. The outer first surface  26  and inner second surface  28  of the mounting plate  12  are preferably curved in a superior to inferior direction, a posterior to anterior direction, and a medial to lateral direction. In addition, and as noted in the embodiments discussed with reference to  FIGS.  3 ,  11 , and  18   , the peripheral edge  30  has a substantial taper for resting upon a matching taper formed along the skull. It is, however, appreciated that this taper may vary (or not exist at all, that is, the peripheral edge  30  may be substantially perpendicular relative to the outer first surface  26  and the inner second surface  28 ) depending upon the specific needs of the procedure. In accordance with a preferred embodiment, the mounting plate  12  will have a preselected thickness not exceeding the space between the inner surface of the scalp and the outer surface of the dura, for example, in the range of around 1 millimeter to 25 millimeters (with areas of strategic bulking and/or thinning) and depending upon the strength of the materials used in the construction of the mounting plate. Preferably, the mounting plate  12  will have a thickness of 1 millimeter to 12 millimeters. As mentioned above, the mounting plate  12  also includes a center aperture  20  designed to accommodate the static cranial implant  16 . The center aperture  20  is defined by an inner wall  32  extending between outer first surface  26  and inner second surface  28  of the mounting plate  12 . 
     In accordance with a preferred embodiment, the mounting plate  12  is fabricated from a wide array of commonly-available biomaterials including, but not limited to, clear and/or opaque PMMA (Poly(methyl methacrylate)), PEEK (Polyether ether ketone), PEKK (Polyetherketoneketone), porous polyethylene, titanium alloy, allograft, autograft, xenograft, and/or various other tissue-engineered constructs. In accordance with one embodiment, the mounting plate  12  is ideally made of clear PMMA since it&#39;s fully lucent and transparent. As will be explained below in greater detail, the transparency also allows for the critical transmission of vital imaging with minimal distortion, such as ultrasound waves for brain pathology detection, and wireless signal communication (i.e., electroencephalography or ECOG)—essential for various neuromodulation devices such as NeuroPace®, for example. Another clear material that may be readily used in accordance with the present invention is cubic zirconium. While clear material is disclosed in accordance with a preferred embodiment, it is appreciated the underlying concepts of the present invention may be achieved through the utilization of an opaque mounting plate  12  as shown with reference to  FIG.  10   . 
     Still further, the mounting plate  12  is constructed of a material allowing for imaging of the brain through the mounting plate  12 , for example, via ultra-sound. It is known that clear PMMA will provide the ability to permit ultra-sound imaging of the brain therethrough so long as it is manufactured without additives that might function to block the radio waves of the imaging device. 
     Considering the static cranial implant  16  it should first be appreciated, the term “static” is used in the description of the present invention because the static cranial implant  16 , has no encapsulated inner working (i.e., “functional”) parts, batteries, wires, or computers, and is essentially an improved “empty-shell” which optimizes the inter-implant positioning within the confines of the skull and the neighboring functional neurosurgical implant  18 . 
     Briefly, and as will be appreciated based upon the following disclosure, the static cranial implant  16  of the present invention is a modified version of a low-profile cranial implant commonly used and known by those skilled in the art of cranial surgical procedures. Such implants may take a variety of forms and are most commonly shaped and dimensioned for integration into the structure of a patient&#39;s skull; that is, the static cranial implant  16  has a geometry that substantially conforms to a resected portion of the patient&#39;s anatomy to which the implant is to be secured. Briefly, the static cranial implant  16  of the present invention includes an outer (commonly convex) first surface  34 , an inner (commonly concave) second surface  36 , and a peripheral edge  38  extending between the outer first surface  34  and the inner second surface  36 . The static cranial implant  16  is shaped and dimensioned for engagement with the skull of the patient upon implantation in a manner well known to those skilled in the field of neurosurgical procedures. The outer first surface  34  and inner second surface  36  of the static cranial implant  16  are preferably curved in a superior to inferior direction, a posterior to anterior direction, and a medial to lateral direction. In addition, and as noted in the embodiments discussed with reference to  FIGS.  3 , 11 , and  18   , the peripheral edge  38  has a substantial taper for resting upon a matching taper formed along the skull. It is, however, appreciated that this taper may vary (or not exist at all, that is, the peripheral edge  38  may be substantially perpendicular relative to the outer first surface  34  and the inner second surface  36 ) depending upon the specific needs of the procedure. In accordance with a preferred embodiment, the static cranial implant  16  will have a preselected thickness not exceeding the space between the inner surface of the scalp and the outer surface of the dura, for example, in the range of around 1 millimeter to 25 millimeters (with areas of strategic bulking and/or thinning) and depending upon the strength of the materials used in the construction of the static cranial implant  16 . Preferably, the static cranial implant  16  will have a thickness of 1 millimeter to 12 millimeters. 
     As mentioned above, the static cranial implant  16  also includes a cavity  22  (for example, formed along the second inner surface  36 ) and optional structural elements  24 , for example, tunnels, channels, pockets, access holes, and/or other structural elements, designed to accommodate various features of the functional neurosurgical implant  18 . In the disclosed embodiment, structural elements  24  in the form of channels are provided. The channels  24  have a first end in communication with the center cavity  22  and a second end extending to the inner second surface  36  (or top surface) of the static cranial implant  16  for the passage of electrodes of the functional neurosurgical implant  18  for applying stimulation to the brain. As many functional neurosurgical implants  18  such as disclosed in  FIGS.  1 ,  2 ,  3 ,  11 ,  12  and  14 - 18    interact with a control device (not shown) via wireless mechanisms, access between the outer first surface  34  and the center cavity  22  may not be required, although it is appreciated channels or other structural elements could certainly be provided for external contact as needed. 
     In accordance with a preferred embodiment, the static cranial implant  16  is fabricated from a wide array of commonly-available biomaterials including, but not limited to, clear and/or opaque PMMA (Poly(methyl methacrylate)), PEEK (Polyether ether ketone), PEKK (Polyetherketoneketone), porous polyethylene, titanium alloy, allograft, autograft, xenograft, and/or various other tissue-engineered constructs. In accordance with one embodiment, the static cranial implant  16  is ideally made of clear PMMA since it&#39;s fully lucent and transparent. This allows for novel inspection of the interdigitated functional neurosurgical implant  14  and neighboring components. As will be explained below in greater detail, it also allows for the critical transmission of vital imaging with minimal distortion, such as ultrasound waves for brain pathology detection, and wireless signal communication (i.e., electroencephalography or ECOG)—essential for various neuromodulation devices such as NeuroPace®, for example. Another clear material that may be readily used in accordance with the present invention is cubic zirconium. While clear material is disclosed in accordance with a preferred embodiment, it is appreciated the underlying concepts of the present invention may be achieved through the utilization of an opaque static cranial implant  16  as shown with reference to  FIG.  10   . 
     The optical clarity of the static cranial implant  16  is important in expanding the potential uses of the universal low-profile intercranial assembly  10  and in expanding the potential functional neurosurgical implants  18  that may be used in conjunction with the present invention. For example, the provision of high optical clarity allows for wireless optical links between the functional neurosurgical implants  18  and remote devices or between functional devices on the interior of the cranium and the exterior of the universal low-profile intercranial assembly  10  (for example, transmitting between the cortex and the other side of the low-profile intercranial device  14 ). Enhanced optical clarity similarly allows for power transmission and/or receipt between the functional neurosurgical implants  18  and devices outside of the static cranial implant  16 . Potential operations that may be achieved through the utilization of optical links through a high clarity static cranial implant  16  include, but are not limited to, device start-up, device calibration, and device operational control. 
     Still further, the static cranial implant  16  is constructed of a material allowing for imaging of the brain through the static cranial implant  16 , for example, via ultra-sound. It is known that clear PMMA will provide the ability to permit ultra-sound imaging of the brain therethrough so long as it is manufactured without additives that might function to block the radio waves of the imaging device. In addition, and with reference to  FIG.  11   , the static cranial implant  16  may include an embedded antibiotic (shown as little dots), which is mixed with the polymer from which the static cranial implant  16  is made, to help reduce the risk of acute or chronic infections from occurring. 
     With reference to  FIGS.  12  and  13   , the static cranial implant  16  may also be provided with an embedded serial number (or implant identifier)  40  that is viewable via CT or MRI (Magnetic Resonance Imaging) scan. In accordance with a preferred embodiment, such embedded serial numbers will be positioned along the inner second surface  36  of the static cranial implant  16 . The embedded serial number  40  is preferably in the form of a QR (Quick Response) Code, that is, a two dimensional barcode offering enhanced patient privacy, ready readability, and vast versatility. The embedded serial number  40  is achieved by integrating various materials that are viewable via CT or MRI scan into the base material of the static cranial implant  16 . For example, the materials may be barium sulfate or zirconium dioxide integrated into the static cranial implant  16  so as to function as a serial number that may be viewed after implant. 
     As shown with reference to  FIG.  14   , the static cranial implant  16  is also preferably constructed with alignment markings  42   a ,  42   b . In accordance with a preferred embodiment, the alignment markings  42   a ,  42   b  run fully across the static cranial implant  16  and are formed in the shape of a cross. As such, the alignment markings include a first alignment marking  42   a  formed upon the static cranial implant  16  to identify the superior to the inferior direction of the universal low-profile intercranial assembly  10  when properly implanted, and a second alignment marking  42   b  formed upon the static cranial implant  16  necessary to identify the posterior to anterior direction of the low-profile intercranial device  14  when properly implanted. These alignment markings  42   a ,  42   b  are preferably formed via laser etching of the static cranial implant as the static cranial implant  16  is fabricated for use in accordance with the present invention. The laser etching may be combined with CNC (Computer Numerically Controlled) techniques to optimize the accuracy of markings or other known marking techniques may be employed were they offer sufficient accuracy to warrant use in accordance with the present invention. 
     The mounting plate  12  of the present invention may be provided with relief recesses  44  (see  FIG.  15   ) for the creation of a perfectly smooth surface when titanium plates are utilized in conjunction with the universal low-profile intercranial assembly  10  for securing the universal low-profile intercranial assembly  10  in a desired position. In accordance with such an embodiment, the relief recesses are 0.4 mm in depth as titanium plates are known to be very thin. 
     Still further, and with reference to  FIG.  16   , the customize static cranial implant  16  may be provided with laser cut lines  46  identifying cuts for various other devices that may be utilized in conjunction with the low-profile intercranial device  14 . For example, the laser cut lines  46  might identify the location of a NeuroPace® neurostimulator device positioned adjacent to the low-profile intercranial device  14 . Still further, the laser cut lines  46  may be utilized for providing insight into the desired location of the low-profile intercranial device  14 . 
     In addition to laser cut lines, laser markings  48  maybe made along the outer first surface  34  or inner second surface  36  of the static cranial implant  16  to provide an indication of critical anatomy relating to the installation of the universal low-profile intercranial assembly  10  in accordance with the present invention. For example, such laser markings  48  might be useful in identifying critical neuro anatomy relating to the functional neurosurgical implant  18  of the low-profile intercranial device  14 . 
     While a preferred static cranial implant  16  is disclosed in accordance with the present invention, the static cranial implant  16  used in conjunction with the present invention may take a variety of forms so long as the static cranial implant includes a center cavity (and, optionally, other structural elements) configured to conform to the exact requirements of the functional neurosurgical implant in accordance with the present invention. For example, the cranial implant might take the form of a cranial device as disclosed in PCT Publication No. WO 2017/039762, entitled “LOW-PROFILE INTERCRANIAL DEVICE,” filed May 2, 2016, which is incorporated herein by reference. 
     While a one-piece construction for the static cranial implant is disclosed above, multiple-piece constructions are contemplated in accordance with the present invention. For example, and with reference to  FIGS.  19 - 22   , the static cranial implant  216  may have a two-piece construction allowing for ready access to the functional neurosurgical implant  218  without the need for complete removal of the low-profile intercranial device  214 . As with the embodiment described above, the two-piece static cranial implant  216  has no encapsulated inner working parts, batteries, wires, or computers, and is essentially an improved “empty-shell.” 
     The two-piece static cranial implant in accordance with this embodiment includes a base cranial implant member  217  and a cover cranial implant member  219 . The base cranial implant member  217  has a geometry that substantially conforms to a resected portion of the patient&#39;s anatomy to which the low-profile intercranial device is to be secured. The base cranial implant member  217  includes an outer (commonly convex) first surface  217   o , an inner (commonly concave) second surface  217   i , and a peripheral edge  217   p  extending between the outer first surface  217   o  and the inner second surface  217   i . The static cranial implant  216  is shaped and dimensioned for engagement with the skull of the patient upon implantation in a manner well known to those skilled in the field of neurosurgical procedures. The outer first surface  217   o  and inner second surface  217   i  of the base cranial implant member  217  are preferably curved in a superior to inferior direction, a posterior to anterior direction, and a medial to lateral direction. 
     The base cranial implant member  217  also includes a center recess  222  formed along the outer first surface  217   o  and optional structural elements  224 , for example, tunnels, channels, pockets, access holes, and/or other structural elements, designed to accommodate various features of the functional neurosurgical implant. As with the prior embodiment, multiple recesses may be employed where the functional neurosurgical implant(s)  218  being used dictates and that the recess  222  need not be directly in the center of the base cranial implant member  217  but may be offset as dictated by the procedure being performed. 
     In accordance with a preferred embodiment, the base cranial implant member  217  is fabricated from a wide array of commonly-available biomaterials including, but not limited to, clear and/or opaque PMMA (Poly(methyl methacrylate)), PEEK (Polyether ether ketone), PEKK (Polyetherketoneketone), porous polyethylene, titanium alloy, and/or various other tissue-engineered constructs. In accordance with one embodiment, the base cranial implant member  217  is ideally made of a clear PMMA since it&#39;s completely transparent and fully lucent. This allows for novel inspection of the interdigitated functional neurosurgical implant and neighboring components. 
     In addition to the base cranial implant member  217 , the two-piece static cranial implant  216  includes a cover cranial implant member  219 . The cover cranial implant member  219  is shaped and dimensioned for positioning over the center recess  222  along the outer first surface  217   o  of the base cranial implant member  217 . In accordance with a preferred embodiment, the cover cranial implant member  219  is secured to the base cranial implant member  217  by screw  221  fixation. The cover cranial implant member  219  includes an outer (commonly convex) first surface  219   o , an inner (commonly concave) second surface  219   i , and a peripheral edge  219   p  shaped and dimensioned for engagement with the outer first surface  217   o  of the base cranial implant member  217  along the periphery of the center recess  222 . As with the base cranial implant member  217 , the outer first surface  219   o  and inner second surface  219   i  of the cover cranial implant member  219  are preferably curved in a superior to inferior direction, a posterior to anterior direction, and a medial to lateral direction. 
     The base cranial implant member  217  and the cover cranial implant member  219  have a total thickness similar to that of the embodiment described above, that is, and depending on the strength characteristics of the materials used, the base cranial implant member  217  and the cover cranial implant member  219  will have a thickness (with areas of strategic bulking and/or thinning) of around 1 millimeter to 25 millimeters, preferably, 1 millimeter to 12 millimeters. 
     As mentioned above, the cover cranial implant member  219  fits over the center recess  222  along the outer first surface  217   o  of the base cranial implant member  217 . In this way, the inner second surface  219   i  of the cover cranial implant member  219  and the outer first surface  217   o  of the base cranial implant member  217 , along the center recess  222 , define a center cavity  223  configured to conform to the exact requirements of the functional neurosurgical implant  218  in accordance with the present invention. With this in mind, the inner second surface  219   i  of the cover cranial implant member  219  may be shaped and/or contoured to enhance the positioning of the functional neurosurgical implant  218  within the center cavity  223 . 
     The functional neurosurgical implant  18  of the present invention is selected from a variety of FDA-approved and experimental options for electrical, optical, mechanical, medicinal and other treatment/monitoring devices designed for long term invasive treatment and/or disease-monitoring of patients requiring such attention. These functional neurosurgical implants  18  are known devices manufactured by various vendors within the neurosurgical industry and have known, unmodifiable dimensions that may be used in the modification of the static cranial implant to optimize surgical results by minimizing abnormal shapes, visible contours, and/or craniofacial deformities. 
     Based upon the functional neurosurgical implant  18  used in conjunction with the present invention, the functional neurosurgical implant may be useful in the treatment of various patient conditions such as epilepsy, movement disorders, chronic pain, spasticity, cerebral palsy, multiple sclerosis, spinal cord injury, traumatic brain injury, attention-deficit/hyperactivity disorder, autism, etc.—and the potential to obtain supra-normal levels of brain function in both military and civilian situations. Furthermore, incorporation of imaging devices within cranial implants could help to provide ongoing tumor bed monitoring for early detection of disease recurrence. 
     By way of example, one potential functional neurosurgical implant  18  that may be employed in accordance with the present invention is a battery-powered functional neurosurgical implant known as the NeuroPace® device, that is, a device for responsive neurostimulation for epilepsy, which has a design flaw in that it limits the visible aesthetic result due to its irregular shape(s), requires placement of battery(ies) within the chest with wires going along the neck, and suffers from high rates of implant micromotion thereby leading to common device infection and bone flap osteomyelitis (See, Wei Z, Gordon C R, Bergey G K, Sacks J M, Anderson W S. Implant Site Infection and Bone Flap Osteomyelitis Associated with the NeuroPace Responsive Neurostimulation System. World Neurosurg 2015 Dec. 29; pii: s1878-8750(15)01775-1.) These deficiencies are overcome in accordance with the present invention by optimizing the static cranial implant for receipt of the NeuroPace® device. 
     With the foregoing in mind, additional functional neurosurgical implants that may be used in conjunction with the present invention include, but are not limited to the following: Deep Brain Stimulators (DBS); Cortical Brain Stimulators (CBS); neurologic medicines that are otherwise prevented from diffusing through the blood-brain barrier via common delivery methods; battery/passively/kinetically/or otherwise-powered functional devices including neuromodulation devices, imaging devices, radiation therapy devices, and remote sensing/monitoring devices; monitoring devices for abnormal levels of intracranial pressure (ICP) or brain activity (i.e., seizures), such as an electrical array for motor/vision cortex control, battery/passively/kinetically/or otherwise-based stimulation hardware for epilepsy management (grids/batteries/wires); low-profile remote imaging devices (e.g., optical coherence tomography (OCT), duplex ultrasound); delivery/sensing devices for electrical impulses; neurological and physiological systems required for deep space/sleep functionalities enhancing the monitoring and/or maintenance of bodily vital signs, nutrition, cognition, etc.; convection enhanced delivery systems effectively delivering therapeutics to substantial volumes of brain and brain tumor; and remote neuro-imaging devices (i.e., electroencephalogram (EEG). 
     The functional neurosurgical implants of the present invention may also incorporate high-precision and fully implantable next-generation neural interface systems taking advantage of microelectronics and photonics along with advances in scalable neural encoding and processing algorithms to demonstrate the transformation of high-definition sensory stimuli to and from sensory cortex areas, bridging physiological and electronic neural activity representations. 
     With this in mind, the term “functional neurosurgical implant” is meant to reference any therapeutic hardware or compositions including, but not limited to, medicines to treat any patient-specific illness, or electronic, mechanical, imaging modality, cerebral spinal fluid (CSF) shunting, and/or electro-mechanical device to remotely monitor (e.g., via Wi-Fi connectivity) or intervene any specific neurologic illness, including imaging, monitoring, electrostimulation, radiation therapy, polarized light/laser neuronal modulation devices. The term “functional” denotes the fact that these implants provide the universal low-profile intercranial assembly with the ability to function as more than a safe custom-shaped skull replacement by providing various functionalities, for example, local drug delivery, monitoring (such as brain monitoring), or local electric stimulation to the patient. 
     The following describes the steps employed in the manufacture and installation of the universal low-profile intercranial assembly  10  of the present invention. While the procedure is described for manufacture and installation of the one—piece customized static cranial implant  16 , the two-piece static cranial implant  216  is processed in the same manner. After the patient is diagnosed as requiring the implantation of a low profile intercranial device  14  as a replacement for a specific portion of the cranium (either to reconstruct a portion of the cranium or to replace a surgeon created defect) in accordance with the claimed invention, the patient first undergoes a high-definition, protocol CT scan of his or her head prior to surgery (which is customary for all neurosurgical patients in need of cranial implants) (see  FIG.  4   ) and the CT scan is then converted to an STL file (or other digital data format useful in computer-assisted design/computer-assisted manufacture (CAD/CAM) manufacture procedures) (see  FIG.  5   ). 
     With the STL file of the CT scan completed, the digital image of the patient (for those patients either with or without an existing skull defect) is used by a design engineer to create a digitally rendered mounting plate  112   a  and a digitally rendered base static cranial implant  116   a  using conventional computer-assisted design (CAD)/computer-assisted modeling (CAM) techniques (See  FIGS.  5  and  6   ). Feedback from a surgeon(s) pre-operatively helps to reveal any unexpected surgical details and aids one in confirming an ideal, planned location of functional neurosurgery and relevant topographical brain anatomy underneath the planned low-profile intercranial device. It is appreciated the CAD/CAM techniques, as well as other automated elements of the present methodology are accomplished using conventional computer and technology equipment  100  well known to those skilled in the art. The digitally rendered mounting plate  112   a  and the digitally rendered base static cranial implant  116   a  exhibit shapes exact to the size, thickness, and contour of the patient&#39;s unique cranium. The digitally rendered mounting plate  112   a  and the digitally rendered base static cranial implant  116   a  are then stored as an STL file (or other digital data format useful in computer-assisted design manufacture procedures). 
     Simultaneously, before or after the creation of the digital design of the cranial implant, a digital rendering of the functional neurosurgical implant (“digitally rendered functional neurosurgical implant  118   a ”) to be used with the static cranial implant is created (or obtained from the third party vendor responsible for the manufacture of the functional neurosurgical implant (See  FIG.  7   ). As with the digitally rendered mounting plate  112   a  and the digitally rendered base static cranial implant  116   a , the digitally rendered functional neurosurgical implant  118   a  is stored as an STL file (or other digital data format useful in computer-assisted design manufacture procedures) commonly used by design engineers using (CAD)/(CAM) techniques and, as explained below, the exact dimensions of the functional neurosurgical implant are incorporated into the final universal low-profile intercranial assembly of the present invention. 
     The digitally rendered functional neurosurgical implant  118   a  is then superimposed on the digitally rendered base static cranial implant  116   a  and the digitally rendered mounting plate  112   a  to produce a hybrid rendering including the digitally rendered mounting plate  112   a , the digitally rendered functional neurosurgical implant  118   a  and the digitally rendered base static cranial implant  116   a  (see  FIG.  8   ). It is appreciated multiple digital renderings of functional neurosurgical implants will be created and superimposed where the planned universal low-profile intercranial assembly includes multiple functional neurosurgical implants. With the digitally rendered functional neurosurgical implant  118   a  superimposed on the digitally rendered base static cranial implant  116   a  and the digitally rendered mounting plate  112   a  as a single superimposed digital drawing (that is, the hybrid rendering), the functional neurosurgical implant, the cranial implant and mounting plate (that is, the digitally rendered versions of both) may be optimized with patient-specific independent width/height/length dimensions to optimize anatomical harmony amongst the functional neurosurgical implant, the static cranial implant, and the mounting plate prior to surgery and allow virtual planning for the seamless integration of the functional neurosurgical implant, the static cranial implant, and the mounting plate. This optimization process results in the optimized hybrid rendering, composed of an optimized digitally rendered functional neurosurgical implant  118   b , the optimized digitally rendered static cranial implant  116   b , and the optimized mounting plate  112   b  as shown in  FIG.  9   . 
     As shown in  FIG.  9   , the optimized digitally rendered mounting plate  112   b , digitally rendered functional neurosurgical implant  118   b , and the optimized digitally rendered static cranial implant  116   b  are optimized such that the final components will have a “key-in-lock” type (that is, a closely conforming or high tolerance) fit. This optimization results in the optimized hybrid rendering composed of the optimized digitally rendered mounting plate  112   b , the optimized digitally rendered functional neurosurgical implant  118   b  and the optimized digitally rendered static cranial implant  116   b.    
     The optimized hybrid rendering offers both pre-operative virtual assessment of the relationship optimized digitally rendered mounting plate  112   b , the optimized digitally rendered static cranial implant  116   b , and the optimized digitally rendered functional neurosurgical implant  118   b , as well as pre-operative optimization of the physical universal low-profile intercranial assembly  10  via known laser-cutting devices facilitated via surgical robot-assisted technologies (or by hand where such capabilities are not available). Both steps help to strengthen the chances that the relationship of mounting plate  12 , static cranial implant  16 , and the functional neurosurgical implant  18  will be optimized down to submillimeter accuracy. Depending upon the needs of the patient, the structure of the optimized digitally rendered mounting plate  112   b , the optimized digitally rendered static cranial implant  116   b , and the optimized digitally rendered functional neurosurgical implant  118   b , the optimized digitally rendered mounting plate  112   b , the optimized digitally rendered static cranial implant  116   b , and the optimized digitally rendered functional neurosurgical implant  118   b  (as well as the resulting universal low-profile intercranial assembly  10  produced as a result of these renderings) will likely have many desired features (for improved safety and aesthetic outcomes relative to the patient appearance). 
     Once the optimized digitally rendered mounting plate  112   b , the optimized digitally rendered static cranial implant  116   b , and the optimized digitally rendered functional neurosurgical implant  118   b  are virtually matched, the anatomical aspects will be ideal for patient-specific needs and the optimized hybrid rendering (saved as an STL (or other digital format)) file is then used to manufacture the present universal low-profile intercranial assembly  10  which may ultimately be assembled. 
     In particular, with the STL (or other digital format) file of the optimized digitally rendered mounting plate  112   b , the optimized digitally rendered static cranial implant  116   b , and the optimized digitally rendered functional neurosurgical implant  118   b , conventional manufacturing techniques are used to fabricate and laser cut the mounting plate  12 , static cranial implant  16  and the functional neurosurgical implant  18  (to the extent necessary) with robot-assistance for extreme accuracy (see PCT Publication No. WO 2016/086049, based upon PCT Application No. PCT/US2015/62516, entitled “A CUTTING MACHINE FOR RESIZING RAW IMPLANTS DURING SURGERY”), as compared to commonly-employed, human hand modification. For example, the mounting plate  12  and the static cranial implant  16  can be obtained in “non-sterile form” from any of the dozens of FDA-approved companies in existence nationwide that are capable of producing cranial implants in accordance with the requirement of the optimized digitally rendered mounting plate and the optimized digitally rendered static cranial implant, respectively. A functional neurosurgical implant  18  corresponding to the optimized digitally rendered functional neurosurgical implant  18  may be purchased from appropriate vendors with or without FDA approval. 
     It is also appreciated that the mounting plate  12 , static cranial implant  16 , and/or the functional neurosurgical implant  18  may be produced through the use of 3-D digital printing technology (see  FIG.  23   ). With this in mind, and in addition to distinctly separate functional neurosurgical implants, the functional neurosurgical implant  18  or portions thereof may be integrated into the static cranial implant  16  through three-dimensional printing. With the use of three-dimensional printing electronic circuitry employed by the functional neurosurgical implant  18  may be created directly on the surfaces of the static cranial implant  16  in a manner optimally utilizing the space available for the remaining portions of the functional neurosurgical implant  18 . Similarly, vital nervous system components may be printed into the static cranial implant  16  or non-clear bony structures designed to resolve complex disabilities may be printed into the static cranial implant  16 . For example, the functional neurosurgical implant  18  or portions thereof may be three-dimensionally printed within the center cavity  22 . Where the two-piece embodiment as described above is employed, the functional neurosurgical implant  18  or portions thereof may be three-dimensionally printed on the center recess  222  of the base cranial implant member  217  or the cover cranial implant member  219 . In another embodiment, the cranial implant  216  and the printable components of the functional neurosurgical implant  218  may be printed in a single print process taking advantage of the three-dimensional printing system&#39;s ability to print multiple materials during a single print job. Ultimately, the application of three-dimensional printing in accordance with the present invention allows immensely complex systems to be compacted into the space needed in the replacement of cranial bones. 
     By manufacturing the present universal low-profile intercranial assembly in this manner, the final physical components of the low-profile intercranial assembly  10 ,  210  that is, the mounting plate  12 , the static cranial implant  16 ,  216  and the functional neurosurgical implant  18 , are virtually matched pre-operatively such that the resulting universal low-profile intercranial assembly  10 ,  210  is ideally constructed to drastically minimize the risk of scalp pain, scalp contour irregularities, extrusion of implant through scalp, painful scalp syndrome, visual craniofacial deformity, and infection secondary to micromotion of foreign materials, and/or brain injuries when being placed underneath the skull. 
     With the universal low-profile intercranial assembly  10 ,  210  fully fabricated, the mounting plate  12  is positioned within the intercranial space so as to replace a portion of the resected portion. Thereafter, the static cranial implant  16 ,  216  and the functional neurosurgical implant  18  are positioned within the center aperture  20  of the mounting plate  12  so as to fully replace the resected portion of the cranium. In accordance with a preferred embodiment, the static cranial implant  16 ,  216  is secured within the center aperture  20  using standard fixation plates and screws made of titanium, although it is appreciated other mechanisms for rigid fixation, for example, tongue and groove coupling structures, wires, sutures, etc., may be employed in securely positioning the static cranial implant. 
     As briefly mentioned above, if it is desired later in the treatment of the patient to replace the functional or structural aspects of the universal low-profile intercranial assembly  10 ,  210  the static cranial implant  16 ,  216  and the functional neurosurgical implant  18  may be removed while the mounting plate  12  is left in position. Thereafter, another low profile intercranial device  14  may be constructed and positioned with the center aperture  20  of the mounting plate  12 . 
     In accordance with a further feature of the present invention, and regardless of which embodiment is being implemented, the mounting plate and/or the static cranial implant may be provided with topographical markings allowing a surgeon to readily and accurately appreciate the thickness of the mounting plate and/or the static cranial implant at specific locations. This is especially important when one considers the transparent nature of the mounting plate and/or the static cranial implant as the transparency allows surgeon to see directly through the mounting plate and/or the static cranial implant but the material might distort the view as the surgeon looks through the mounting plate and/or the static cranial implant. 
     In particular, and as shown in  FIGS.  24 A to  24 B , the mounting plate  312 ,  412  and the static cranial implant  316 ,  416  are provided with topographical markings  360 ,  460 . In accordance with a preferred embodiment of the present invention, the topographical markings  360 ,  460  are composed of contour lines  362 ,  462  produced by connecting points of the static cranial implant  316 ,  416  or mounting plate  312 ,  412  having equal thickness together to create a continuous line. As a specific contour line designates a specific thickness of the mounting plate  312 ,  412  and the static cranial implant  316 ,  416 , the thickness designated by specific the contour lines is established in a systematic manner. For example, contour lines  362  of a specific color could designate a specific thickness or contour lines  462  could be annotated with numbers  262   n  indicating the thickness in much the same manner contour lines are used in topographic maps. Where the contour lines  362  are designated by colors, the mounting plate and/or the cranial implant may be provided with a key  366  specifying the meaning of the various colors. It is further appreciated the contour lines may be formed via various known mechanisms, for example, laser etching, molding, 3-D printing, etc. 
     The contour lines themselves may be formed on the outer first surface(s) of the mounting plate  312 ,  412  and/or the static cranial implant  316 ,  416 , the inner second surface(s) of the mounting plate  312 ,  412  and/or the static cranial implant  316 ,  416 , or within the mounting plate  312 ,  412  and/or the static cranial implant  316 ,  416  at a position between the outer first surface(s) and inner second surface(s). 
     While the preferred embodiments have been shown and described, it will be understood that there is no intent to limit the invention by such disclosure, but rather, is intended to cover all modifications and alternate constructions falling within the spirit and scope of the invention.