Three-Dimensional CAD in Skull Reconstruction: A Narrative Review with Focus on Cranioplasty and Its Potential Relevance to Brain Sciences (original) (raw)

A Comprehensive 3D-Molded Bone Flap Protocol for Patient-Specific Cranioplasty

2021

We present a detailed step-by-step approach for the low-cost production and surgical implantation of cranial prostheses, aimed at restoring aesthetics, cerebral protection, and facilitating neurological rehabilitation. This protocol uses combined scan computed tomography (CT) cross-sectional images, in DICOM format, along with a 3D printing (additive manufacturing) setup. The in-house developed software InVesalius®️ is an open-source tool for medical imaging manipulation. The protocol describes image acquisition (CT scanning) procedures, and image post-processing procedures such as image segmentation, surface/volume rendering, mesh generation of a 3D digital model of the cranial defect and the desired prostheses, and their preparation for use in 3D printers. Furthermore, the protocol describes a detailed powder bed fusion additive manufacturing process, known as Selective Laser Sintering (SLS), using Polyamide (PA12) as feedstock to produce a 3-piece customized printed set per patie...

Cranial reconstruction: 3D biomodel and custom-built implant created using additive manufacturing

Journal of Cranio-Maxillofacial Surgery, 2014

Additive manufacturing (AM) technology from engineering has helped to achieve several advances in the medical field, particularly as far as fabrication of implants is concerned. The use of AM has made it possible to carry out surgical planning and simulation using a three-dimensional physical model which accurately represents the patient's anatomy. AM technology enables the production of models and implants directly from a 3D virtual model, facilitating surgical procedures and reducing risks. Furthermore, AM has been used to produce implants designed for individual patients in areas of medicine such as craniomaxillofacial surgery, with optimal size, shape and mechanical properties. This work presents AM technologies which were applied to design and fabricate a biomodel and customized implant for the surgical reconstruction of a large cranial defect. A series of computed tomography data was obtained and software was used to extract the cranial geometry. The protocol presented was used to create an anatomic biomodel of the bone defect for surgical planning and, finally, the design and manufacture of the patient-specific implant.

3D modeling, custom implants and its future perspectives in craniofacial surgery

Annals of maxillofacial surgery, 2014

Custom implants for the reconstruction of craniofacial defects have gained importance due to better performance over their generic counterparts. This is due to the precise adaptation to the region of implantation, reduced surgical times and better cosmesis. Application of 3D modeling in craniofacial surgery is changing the way surgeons are planning surgeries and graphic designers are designing custom implants. Advances in manufacturing processes and ushering of additive manufacturing for direct production of implants has eliminated the constraints of shape, size and internal structure and mechanical properties making it possible for the fabrication of implants that conform to the physical and mechanical requirements of the region of implantation. This article will review recent trends in 3D modeling and custom implants in craniofacial reconstruction.

Rapid prototyping technology for cranioplasty: A case series

The Journal of Indian Prosthodontic Society, 2019

Cranioplasty is defined as the surgical repair of acquired or congenital cranial defects. The objective of cranioplasty includes protection of brain, reconstruction of lost anatomical part, and esthetics. There are many indications of cranioplasty such as trauma, decompressive craniectomies, tumors, complications of previous cranioplasties, and congenital deformities. Rehabilitation of patients with cranial defects requires a multidisciplinary approach, and such patients often pose Cranial vault defects may be acquired or congenital in origin. Rehabilitation of these patients often poses challenge to the operating team and prosthodontist. Polymethylmethacrylate is a commonly used alloplastic graft material which is used for the fabrication of cranial prosthesis. Nowadays, with the advancement in the bioengineering, custom-made template and cranial prosthesis can be made by rapid prototyping technology (RPT) by patient three-dimensional (3D) computed tomography (CT) scan images. This series of two cases explained two different techniques for the rehabilitation of the patient with frontotemporoparietal cranial defect. Case 1 had a history of cerebrovascular accident, followed by decompression craniotomy which led to frontotemporoparietal defect of the left side. This defect area was associated with the cerebrospinal fluid accumulation which made delineation of underlying bony margins difficult and interfered with conventional impression procedures. Case 2 had a road traffic accident which led to intracerebral hemorrhage followed by decompression craniotomy which resulted in frontotemporoparietal defect of the right side. The patient had a poor neuromuscular control which impedes with the upright posture of the head during impression making of the defect area. Therefore, these cases were planned to rehabilitate by RPT. In these techniques, the prosthesis was made using custom-made skull template produced by RPT, using the data of 3D-CT scan images. This technique resulted in the prosthesis with good esthetics and better fit of the prosthesis. The contours of the prosthesis were replicated in the same manner as compared to the contralateral side. RPT is an additive manufacturing technology which is now used in the field of dentistry too. This technique is easy to use; fabricate prosthesis with high precision is less time-consuming and has fewer chances of error.

Customized alloplastic cranioplasty of large bone defects by 3D-printed prefabricated mold template after posttraumatic decompressive craniectomy: A technical note

Surgical Neurology International

Background: Manufacturing of customized three-dimensional (3D)-printed cranioplastic implant after decompressive craniectomy has been introduced to overcome the difficulties of intraoperative implant molding. The authors present and discuss the technique, which consists of the prefabrication of silicone implant mold using additive manufacturing, also known as 3D printing, and polymethyl methacrylate (PMMA) implant casting. Methods: To reconstruct a large bone defect sustained after decompressive craniectomy due to traumatic brain injury (TBI), a 3D-printed prefabricated mold template was used to create a customized PMMA implant for cranial vault repair in five consecutive patients. Results: A superb restoration of the symmetrical contours and curvature of the cranium was achieved in all patients. The outcome was clinically and cosmetically favorable in all of them. Conclusion: Customized alloplastic cranioplasty using 3D-printed prefabricated mold for casting PMMA implant is easy to...

Importance of Three-Dimensional Modeling in Cranioplasty

Journal of Craniofacial Surgery, 2019

Cranioplasty is a reconstruction operation made to protect intracranial structures. It is applied for the closure of bone defects occurring due to causes such as trauma, tumor, infection, and infarct. Many different products changing from autologous bone grafts to synthetic materials are used for cranioplasty. Threedimensional printers that are among the popular innovations of today are used gradually more in medical area as in every field of life and they make the surgical operation easier. When customizable materials are combined with technology, the authors come across successful results and less complications. The aim of the authors' study was to show a 3-dimensional modeling method in 2 patients the authors applied cranioplasty and the advantages provided by this method for the surgeon and the patient.

Biomaterials for Reconstruction of Cranial Defects

Arquivos Brasileiros de Neurocirurgia, 2016

Cranioplasty is defined as the surgical repair of a cranial defect to restore the structure and function of the skull. Archaeological records show attempts of cranioplasty since the dawn of human civilization, but until today there is no consensus among neurosurgeons around the world-regarding the best material for cranioplasty. Relocation of the originally removed bone graft is still the best option, but is not always available. In modern cranioplasty, different materials can be used for the repair of cranial defects, such as metals, plastics, acrylics, and ceramics. Recent studies have sought to identify which materials provide the best long-term results, but scientific evidence is poor. Presurgical decisions must consider the experience of the surgical service and the individual conditions of the patient. In this study, we discuss the main characteristics of the materials used today for the reconstruction of cranial defects.

The feasibility of producing patient-specific acrylic cranioplasty implants with a low-cost 3D printer

Journal of Neurosurgery, 2015

OBJECT Commercially available, preformed patient-specific cranioplasty implants are anatomically accurate but costly. Acrylic bone cement is a commonly used alternative. However, the manual shaping of the bone cement is difficult and may not lead to a satisfactory implant in some cases. The object of this study was to determine the feasibility of fabricating molds using a commercial low-cost 3D printer for the purpose of producing patient-specific acrylic cranioplasty implants. METHODS Using data from a high-resolution brain CT scan of a patient with a calvarial defect posthemicraniectomy, a skull phantom and a mold were generated with computer software and fabricated with the 3D printer using the fused deposition modeling method. The mold was used as a template to shape the acrylic implant, which was formed via a polymerization reaction. The resulting implant was fitted to the skull phantom and the cranial index of symmetry was determined. RESULTS The skull phantom and mold were su...

Design and Manufacturing of a Custom Skull Implant

Problem statement: Cranioplasty is defined as a neurosurgical procedure to cover an injured bone in the skull. This procedure is carried out in order to protect and restore intracranial structures and to restore the appearance and psychological stability of the patient. Advances in medical imaging, such as MRI and CT, have allowed the 3D reconstruction of anatomical structures for several medical applications, including the design of custom-made implants. This study describes the methodology used to design a custom-made cranial implant for a 13-year-old patient who suffered a lesion in the left frontoparietal region of the skull caused by a fall. Approach: The design of the implant was based on the 3D reconstruction of the skull of the patient, obtained by a CT scan, using Rapid Form® 2006. Once the preliminary design was completed, 3D models of the injured region of the skull and of the implant were fabricated in a Rapid Prototyping (RP) machine using Fused Deposition Modeling Technology (FDM) with the purpose of functionally and dimensionally validating the implant. Subsequently, the implant was fabricated using a 1.2-mm-thick Titanium Alloy (Ti6Al4V) plate. Results: The prosthesis was successfully implanted. The surgical time was 85% shorter than that for the same type of surgery in which standard commercial implants and titanium meshes are used. This decrease in surgery time is primarily the result of eliminating the need for trial and error procedures to achieve a good fit for the implant. Finally, the appearance of the patient was restored, allowing the patient to safely perform daily activities. Conclusion: The use of 3D reconstruction techniques from medical images reduces the possibility of errors during surgery, improves fit and provides better implant stability. The use of 3D models designed in RP proved to be an effective practice in the design process.

The “springform” technique in cranioplasty: custom made 3D-printed templates for intraoperative modelling of polymethylmethacrylate cranial implants

Acta Neurochirurgica

Background Manual moulding of cranioplasty implants after craniectomy is feasible, but does not always yield satisfying cosmetic results. In contrast, 3D printing can provide precise templates for intraoperative moulding of polymethylmethacrylate (PMMA) implants in cranioplasty. Here, we present a novel and easily implementable 3D printing workflow to produce patient-specific, sterilisable templates for PMMA implant moulding in cranioplastic neurosurgery. Methods 3D printable templates of patients with large skull defects before and after craniectomy were designed virtually from cranial CT scans. Both templates — a mould to reconstruct the outer skull shape and a ring representing the craniectomy defect margins — were printed on a desktop 3D printer with biocompatible photopolymer resins and sterilised after curing. Implant moulding and implantation were then performed intraoperatively using the templates. Clinical and radiological data were retrospectively analysed. Results Sixteen...