Cranioplasty Implants Research Articles

Place de la cranioplastie dans la prise en charge des crâniectomies décompressives : étude de la cohorte de l’Hôpital Fondation Adolphe de Rothschild sur 7 ans

The objective of our study is to take stock of the cranioplasty implants used within our establishment. We analyzed the patients files who underwent craniectomy followed by cranioplasty between 2017 and 2023, with at least 1 year of follow-up after cranioplasty (n=75). The data were extracted from the computerized patient file (DxCare®, Dédalus) and the pharmaceutical management tool for drugs and sterile medical devices (Pharma®, Computer Engineering). The sex ratio, indication for craniectomy, operating time, time between craniectomy and cranioplasty, complications and aesthetic result were statistically analyzed. The main indications are stroke (n=59; 78.5%) and aneurysms (n=7; 9.5%). Among the 75 patients, 52 benefited from the placement of a custom implant (PolyEtherEtherCetone/PEEK or Hydroxyapatite) and 23 from cementoplasty. The operating time was significantly shorter (p < 0.05) for custom cranioplasty (1.93 ± 0.61 h vs 1.62 ± 0.53). Only 4 patients (5.3%) were not satisfied with the aesthetic result following the placement of a custom implant. A greater risk of infection was found in the context of cementoplasty (43% for cementoplasties vs 25% for the custom implant, so χ2(p = 0.1095), this difference not being statistically significant. This collaborative work between the pharmacy and the adult neurosurgery department served to establish an initial register for monitoring patients who have undergone cranioplasty for whom the ideal implant remains to be determined.

Neural shape completion for personalized Maxillofacial surgery

In this paper, we investigate the effectiveness of shape completion neural networks as clinical aids in maxillofacial surgery planning. We present a pipeline to apply shape completion networks to automatically reconstruct complete eumorphic 3D meshes starting from a partial input mesh, easily obtained from CT data routinely acquired for surgery planning. Most of the existing works introduced solutions to aid the design of implants for cranioplasty, i.e. all the defects are located in the neurocranium. In this work, we focus on reconstructing defects localized on both neurocranium and splanchnocranium. To this end, we introduce a new dataset, specifically designed for this task, derived from publicly available CT scans and subjected to a comprehensive pre-processing procedure. All the scans in the dataset have been manually cleaned and aligned to a common reference system. In addition, we devised a pre-processing stage to automatically extract point clouds from the scans and enrich them with virtual defects. We experimentally compare several state-of-the-art point cloud completion networks and identify the two most promising models. Finally, expert surgeons evaluated the best-performing network on a clinical case. Our results show how casting the creation of personalized implants as a problem of shape completion is a promising approach for automatizing this complex task.

Reconstruction and evaluation of 3D Printing PMMA cranioplasty implants

Reconstruction and evaluation of 3D Printing PMMA cranioplasty implants

The Applicability of Polyetheretherketone and Titanium Mesh in Cranioplasty: A Retrospective Comparative Analysis

Objective: To compare the clinical application effect and safety of polyetheretherketone (PEEK) and titanium mesh (TM) in cranioplasty. Methods: Four-year retrospective comparison of patients (96 cases) undergoing synthetic cranioplasty with PEEK or TM. The patients were divided into the PEEK group (24 cases) and the TM group (72 cases) according to the implants, and the patient demographics, general conditions before the operation, postoperative complications, length of postoperative hospital stay, total costs, satisfaction with shaping and long-term complications were compared between the 2 groups. Results: Patients in the PEEK group were younger than those in the TM group (P=0.019). Hospitalization costs were significantly higher in the PEEK group than in the TM group (P&lt;0.001). The incidence of postoperative subcutaneous effusion was 33% in the PEEK group and 6.9% in the TM group, which suggests that patients in the PEEK group had a higher risk of postoperative subcutaneous effusion (P=0.001). There was no significant difference in the incidence of long-term complications and cosmetic satisfaction between the 2 groups at 4 years postoperatively. Conclusions: In this study, both titanium mesh and PEEK are reliable implants for cranioplasty. Titanium mesh is widely used in cranioplasty due to its cost-effective performance. PEEK has gradually gained recognition due to the characteristics of the material and surgical procedure, but the price needs to be further reduced, and attention should be paid to the occurrence and treatment of early postoperative subcutaneous effusion.

Is Polyetheretherketone an Effective Alloplastic Material in Comparison to Titanium in Calvarial Reconstruction.

Polyetheretherketone (PEEK) and titanium (Ti) cranioplasty implants ideal outcomes are good esthetics, long-term stability, and protection of the fragile brain tissue. However, it is unclear whether PEEK implants can offer an equal alternative to Ti implants. This work aimed to critically review papers and case series published on both Ti and PEEK Cranioplasty regarding complications, clinical outcomes, ease of use, esthetics, manufacture and availability, cost and time-saving factors, postoperative quality of life (QOL), as well as their suitability for the fronto-orbito region reconstruction. PubMed database was sourced for published literature in the period 2007 to the end of 2023; a further manual search for articles was carried out on the reference lists of each paper. A total of 48980 papers were found during the initial search, but only 33 articles met the inclusion criteria. A total of 6023 cranial implants, with 3879 being Ti and 1205 PEEK. Titanium was the material of choice in over 64.4% of cases; however, Ti has been in application for many years compared to PEEK. Out of the 33 papers, there was 27 retrospective cohort/analysis/case series and reviews: 1 meta-analysis, 2 systematic reviews and 3 randomized control trials. Four articles commented on the QOL, 15 on esthetics, 7 discussed cost and time-saving without measurable variables, and 7 articles looked explicitly at the complex fronto-orbito region, of which 49% were primary 1-stage surgical reconstructions, 54% were reconstructed with PEEK and 7% Ti (CAD/CAM). There is no absolute consensus for the preference of either material, however, in the fronto-orbito region, PEEK is the material of choice for ease of use, esthetics, and time-saving. However, there are no long-term studies on PEEK cranioplasty, and fewer in comparison with Ti implants. Further research is required in this field. No reliable or measurable data was found to determine the QOL, esthetics, cost, or time-saving elements.

A Single Standard Polyvinyl Chloride 3D Skull Model to Create the Polymethyl Methacrylate Cranioplasty Flap: A Novel and Low-Cost Technique.

Although, cranioplasty is a commonly performed neurosurgical procedure worldwide, the cost of available cranioplasty implants is a major issue in a low-income country like India. The aims of this study were to introduce a novel and low-cost technique using a single standard three-dimensional (3D) skull model to guide the polymethyl methacrylate (PMMA) cranioplasty flap production and to evaluate the functional and cosmetic outcomes. We retrospectively evaluated 47 cases of PMMA cranioplasty in the period from February 2019 to June 2022. A single standard 3D skull model was used to make the PMMA cranioplasty flaps. The overall cost of this PMMA implant was compared with that of other available cranioplasty implants. The functional and cosmetic outcomes were evaluated postoperatively. The mean age of our patients was 37.17 ± 13.83 years and the age range was 17 to 63 years. The primary cause of surgery was trauma in the majority of cases (n = 31, 65.96%). The mean operative time was 78.55 ± 19.82 minutes. The cosmetic results were very satisfying in 46 of 47 (97.87%) patients and moderately satisfying in 1 (2.12%) patient. Overall, there were three (6.38%) complications. Our technique provides excellent functional and cosmetic outcomes. The overall surgical cost of these PMMA implants was lower than that of the other available cranioplasty implants. This technique is currently the most cost-effective option for cranioplasty.

879 Comparison of Perioperative and Long-Term Outcomes Following PEEK and Autologous Cranioplasty: A Single Institution Experience

INTRODUCTION: Cranioplasty is a common neurosurgical procedure to correct congenital or acquired skull defects. Three-dimensionally (3D) printed polyether-ether-ketone (PEEK) implants are a relatively novel option for cranioplasty that has gained popularity in recent years. However, there is ongoing debate with respect to this material’s efficacy and safety compared to autologous bone grafts. The purpose of this study was to offer our institution’s experience and add to the growing body of literature on the topic. METHODS: A single-institution retrospective analysis of patients undergoing cranioplasties between 2016 and 2021 was performed. Patients were divided into PEEK and autologous cranioplasty cohorts. Parameters of interest included patient demographics as well as perioperative (&lt;3 months postoperative) and long-term outcomes (&gt;3 months postoperative). A p-value &lt;0.05 was considered statistically significant. RESULTS: A total of 31 patients met inclusion criteria (PEEK: 15, Autologous: 16). Mean age of the entire cohort was 51.7 years (range 19-81 years). Baseline demographics using the modified frailty index (mFI) revealed greater rate of comorbidities in the autologous group (p = 0.073), which was accounted for in statistical analyses. Multiple logistic regression model revealed a significantly higher rate of surgical site infection during the immediate postoperative period in the autologous cohort (31.3% vs. 0%, p = 0.011). Otherwise, perioperative and long-term complication profiles were similar between groups. Additionally, a generalized linear model demonstrated that both cohorts had similar mean hospital length of stay (LoS) (autologous: 16.1 vs. PEEK: 10.7 days). CONCLUSIONS: PEEK cranioplasty implants may offer a more favorable perioperative complication profile with similar long-term complication rates and hospital LoS compared to autologous bone implants. Future studies are warranted to confirm our findings in larger series, and further examine the utility of PEEK in cranioplasty.

Template Routed Patient-Specific Implant for 1-Stage Cranioplasty.

Cranial reconstruction presents a significant challenge in cases involving pathologies with skull invasion, and various techniques have been used, including the intraoperative shaping of titanium mesh and the manual sculpting of bone cement serving as surrogates for the excised bone graft. In the context of prefabricated patient-specific implants (PSIs) for cranioplasty, precise surgical execution of craniotomies is paramount. This ensures optimal congruity between the implant and the defect created during the craniotomy, leading to a successful single-stage procedure encompassing both bone removal and reconstruction. This article presents a meticulous method for achieving such high-fidelity craniotomy and subsequent cranioplasty using PSIs in a single-stage surgery. The procedure was implemented for 2 cases of meningiomas with osseous invasion. Through meticulous preoperative planning, the craniotomy template and implant were designed using computer-assisted design and manufactured on a 3-dimensional printer using the patient's computed tomography scans. Intraoperative fabrication of sterile polymethyl methacrylate replicas was achieved through the creation of silicone molds and subsequent injection molding techniques. Predesignated screw holes facilitated neuronavigation-assisted positioning of the template, aligning it accurately with the target site using registration points. Mini-screws firmly secured the template to the skull. Guided by the template, a craniotomy router performed the bone resection. On completion, the implant was affixed into place using plates and screws. This technique demonstrably facilitated a cost-effective, streamlined and precise application of prefabricated PSIs within a single-stage craniotomy-cranioplasty procedure. Subjective patient reports indicated high levels of satisfaction with the outcome. The template routed patient-specific implant 1-stage cranioplasty technique refines previous approaches through precise template localization on the skull, enabling an accurate craniotomy to match a prefabricated PSI. This single-stage procedure rivals hand-shaped methods in aesthetics and compares with the outcomes of 2-stage PSI cranioplasties. Additional studies are needed to validate our results.

Additively manufactured patient specific implants: A review

Medical applications of additive manufacturing have seen a significant growth in recent years due to availability of advanced medical imaging and design software and wide range of materials. The range of additively manufactured medical implants is growing rapidly and surgeons need to keep themselves updated with state-of-the-art of the technology. This article reviews several articles related to medical implants to help surgeons and researchers to stay up-to-date on recent developments in the domain. Additively manufactured medical implants are reviewed into five categories: orthopedic implants, dental implants, cranioplasty implants, scaffold implants for tissue engineering and other medical implants including chest wall reconstructive implants, anti-migration enhanced tracheal stents, and buccopharyngeal stents. Additive manufacturing process and material for fabrication of each type of implant are highlighted in the study. It has been observed that titanium alloy is a suitable material for cementless arthroplasty. Porosity in the implants supports bone ingrowth, which results in a significant reduction in stress shielding. Additive manufacturing has a very attractive future in medical implant fabrication due to its capability to produce complex and customized implants. The AM provides freedom to researcher to explore the complex design of medical implants for better bone regeneration and improved osseointegration.

Personalized 3D-printed cranial implants for complex cranioplasty using open-source software.

Cranioplasty is a routine neurosurgery treatment used to correct cranial vault abnormalities. Utilization of 3D printing technology in the field of cranioplasty involving the reconstruction of cranial defects emerged as an advanced possibility of anatomical reshaping. The transformative impact of patient-specific 3D printed implants, focuses on their remarkable accuracy, customization capabilities, and enhanced biocompatibility. The precise adaptation of implants to patient-specific anatomies, even in complex cases we presented, result in improved aesthetic outcomes and reduced surgical complications. The ability to create highly customized implants addresses the functional aspects of cranial defects and considers the psychological impact on patients. By combining technological innovation with personalized patient care, 3D printed cranioplasty emerges as a transformative avenue in cranial reconstruction, ultimately redefining the standards of success in neurosurgery. 3D printing allows an excellent cranioplasty cosmesis achieved at a reasonable price without sacrificing patient outcomes. Wider implementation of this strategy can lead to significant healthcare cost savings.

The Use and Outcomes of 3D Printing in Pediatric Craniofacial Surgery: A Systematic Review.

Three-dimensional (3D) printing has demonstrated efficacy in multiple surgical specialties. As accessibility improves, its use in specific fields deserves further attention. We conducted a systematic review of the implementation and outcomes of 3D printing in pediatric craniofacial surgery, as none has been performed. A systematic review was conducted according to Cochrane and PRISMA guidelines. PubMed, Embase, Cochrane library, and Clinicaltrials.gov were queried with combinations of the terms: "3D printing," "craniofacial," "surgery," and "pediatric." Original human studies containing patients <18 years old implementing 3D printing to aid in craniofacial surgery were included. Study selection, grading, and data extraction were performed independently by multiple authors. After screening 120 articles, 7 (3 case series and 4 case reports) were included, published from 2017 to 2022. All studies addressed patients with different disease processes including craniosynostosis, cleft lip/palate, and mandibular hypoplasia. 3D printing was used to create mock surgical models in 2 studies, intraoperative cutting guides/molds (CGs) in 6 studies, and cranioplasty implants in 2 studies. Two case series determined the accuracy of the CGs was acceptable within historical comparison, while 4 articles included subjective statements on improved accuracy. Five studies noted reduced operating time, 2 noted reduced intraoperative blood loss, and 1 felt the use of 3D printed materials was responsible for shorter hospitalization duration. No adverse events were reported. Despite the limitations of the current literature, all studies concluded that the use of 3D printing in pediatric craniofacial surgery was beneficial. Definitive conclusions cannot be made until further controlled research is performed.

Complications and Hardware Failure Following Synthetic Cranioplasty Implants and Free Flap Coverage

Complications and Hardware Failure Following Synthetic Cranioplasty Implants and Free Flap Coverage

Comparison of Perioperative and Long-term Outcomes Following PEEK and Autologous Cranioplasty: A Single Institution Experience and Review of the Literature

Three-dimensionally (3D) printed polyether-ether-ketone (PEEK) implants are a relatively novel option for cranioplasty that have recently gained popularity. However, there is ongoing debate with respect to material efficacy and safety compared to autologous bone grafts. The purpose of this study was to offer our institution's experience and add to the growing body of literature. A single-institution retrospective analysis of patients undergoing cranioplasties between 2016 and 2021. Patients were divided into PEEK and autologous cranioplasty cohorts. Parameters of interest included patient demographics as well as perioperative (<3 months postoperative) and long-term outcomes (>3 months postoperative). A P value < 0.05 was considered statistically significant. A total of 31 patients met inclusion criteria (PEEK: 15, Autologous: 16). Mean age of total cohort was 48.9 years (range 19-82 years). Modified Frailty Index (mFI) revealed greater rate of comorbidities among the Autologous group (P= 0.073), which was accounted for in statistical analyses. Multiple logistic regression model revealed significantly higher rate of surgical site infection in the Autologous cohort (31.3% vs. 0%, P= 0.011). Minor complications were similar between groups, while the Autologous group experienced significantly more major postoperative complications (50%) versus PEEK (13.3%) (P= 0.0291). Otherwise perioperative and long term complication profiles were similar between groups. Additionally, generalized linear model demonstrated both cohorts had similar mean hospital length of stay (LoS) (Autologous: 16.1 vs. PEEK: 10.7 days). PEEK cranioplasty implants may offer more favorable perioperative complication profiles with similar long-term complication rates and hospital LoS compared to autologous bone implants. Future studies are warranted to confirm our findings in larger series, and further examine the utility of PEEK in cranioplasty.

Outcomes of Cranioplasty Reconstructions: Review of Cranioplasty Implants and Free Flap Coverage Variables that Affect Implant Exposure.

Complex scalp wounds with cranial/dural involvement are challenging to reconstruct. Successful reconstruction can be achieved with cranial implants/hardware and free flap coverage. Wounds can breakdown and require revision procedures. We addressed reconstructive outcomes of different implants requiring free flaps. To determine the factors associated with implant exposure. Multi-institutional retrospective review of 82 patients, 2000-2020, repaired with cranial implants and free flap coverage. Implant exposure occurred in 13/82 (16%) reconstructions. Flap atrophy or thinning leading to implant exposure occurred in 11/82 (13%) reconstructions, including partial flap atrophy OR 0.05 (95% CI 0.0-0.35) and total flap atrophy OR 0.34 (95% CI 0.02-19.66). Revision surgeries that occurred subsequent to flap reconstruction were also associated with implant exposure (OR 0.02 (95% CI 0.0-0.19)). Implant exposure was not associated with radiation therapy, patient health history, implant type, flap type, or postoperative complications. Implant exposure is associated with free flap atrophy, leading to inadequate implant coverage and the need for revision surgeries. Completing reconstruction with adequate soft tissue bulk and coverage and avoiding revision surgery may decrease the risk for implant exposure over time. 4 Laryngoscope, 133:2954-2958, 2023.

Considerations for Choice of Cranioplasty Material for Pediatric Patients

Introduction: Optimal material and timing of cranioplasty in the pediatric population continue to be debated. Autologous and alloplastic materials have various indications for use and risk factors for complications. Methods: A single-center retrospective cohort study was undertaken of all pediatric patients who underwent cranioplasty with any material from 1991–2021. Results: 149 cranioplasty implants were included. Younger age (6 years old or under), a diagnosis of craniosynostosis as reason for implant, use of autologous bone, and shorter times to cranioplasty were predictive of need for revision surgery. No factors studied had a statistically significant impact on rate of removal of implant at time of revision surgery. Conclusion: Autologous and alloplastic cranioplasty materials both have good outcomes with low rates of revision surgery in the pediatric population. Alloplastic implants may be considered in the setting of infection as reason for craniectomy given the lower rate of revision surgery and need for removal. Patients with craniosynostosis as reason for cranioplasty have a higher risk of requiring revision or additional surgeries, regardless of implant used.

Analysis of PMMA versus CaP titanium-enhanced implants for cranioplasty after decompressive craniectomy: a retrospective observational cohort study

Numerous materials of implants used for cranioplasty after decompressive craniectomy (DC) have been investigated to meet certain demanded key features, such as stability, applicability, and biocompatibility. We aimed to evaluate the feasibility and safety of biocompatible calcium-phosphate (CaP) implants for cranioplasty compared to polymethylmethacrylate (PMMA) implants. In this retrospective observational cohort study, the medical records of all patients who underwent cranioplasty between January 1st, 2015, and January 1st, 2022, were reviewed. Demographic, clinical, and diagnostic data were collected. Eighty-two consecutive patients with a mean age of 52 years (range 22–72 years) who received either a PMMA (43/82; 52.4%) or CaP (39/82; 47.6%) cranial implant after DC were included in the study. Indications for DC were equally distributed in both groups. Time from DC to cranioplasty was 143.8 ± 17.5 days (PMMA) versus 98.5 ± 10.4 days (CaP). The mean follow-up period was 34.9 ± 27.1 months. Postoperative complications occurred in 13 patients with PMMA and 6 in those with CaP implants (13/43 [30.2%] vs. 6/39 [15.4%]; p = 0.115). Revision surgery with implant removal was necessary for 9 PMMA patients and in 1 with a CaP implant (9/43 [20.9%] vs. 1/39 [2.6%]; p = 0.0336); 6 PMMA implants were removed due to surgical site infection (SSI) (PMMA 6/43 [14%] vs. CaP 0/39 [0%]; p = 0.012). In this study, a biocompatible CaP implant seems to be superior to a PMMA implant in terms of SSI and postoperative complications. The absence of SSI supports the idea of the biocompatible implant material with its ability for osseointegration.

Neuroimaging through Sonolucent Cranioplasty: A Systematic Scoping Review Protocol.

Cranioplasty is a neurosurgical procedure in which the skull bone is repaired after craniectomy. Recently, studies have suggested that sonolucent synthetic materials are safe and useful for cranioplasty. Sonolucent cranioplasty (SC) implants provide unprecedented opportunity in adult neurosurgery to monitor neuroanatomy, assess hemodynamics, view devices located within the implant, and conduct focused ultrasound treatments. Current research on SC includes proof-of-concept cadaveric studies, patient-related safety and feasibility studies, and case series demonstrating transcranioplasty ultrasonography (TCUS). The purpose of this protocol is to investigate the current literature on SC use and outcomes in TCUS. We will perform a systematic literature search following PRISMA-ScR guidelines. The search will be conducted using Ovid Embase, Ovid Medline, and Web of Science Core Collection databases. Titles, abstracts, and full texts will be screened. Joanna Briggs Institute critical appraisal tools will be utilized. Data extraction points will include subject characteristics, SC implant characteristics, ultrasound characteristics, and sonographic findings. These findings will provide a comprehensive review of the literature on sonolucent cranioplasty and directions for future research.

Skull Reconstruction Using a Custom-Made, Three-Dimensional–Printed, Hydroxyapatite-Titanium Cranioplasty Implant: Largest Single-Center U.S. Experience

Although several material options, both natural and synthetic, are available for cranioplasty, the rate of implant-related complications has remained high. A relatively novel, synthetic hydroxyapatite-titanium implant, which combines biocompatibility with biomechanical resilience, has been reported to reduce tissue inflammation, infection, and explantation rates, while delivering superior cosmetic results. However, despite such promising preliminary reports, clinical data supporting its use have remained scarce. All the patients who had undergone cranioplasty between 2019 and 2022 using this implant were identified from a prospectively maintained database. Medical records were retrospectively reviewed and the following variables recorded: demographic data, clinical data, radiologic findings, operative details, complications (implant-related and unrelated), and outcomes. A total of 18 patients (12 men and 6 women), with a mean age of 39 years (range, 20-70 years), were identified. The indications for craniectomy were traumatic brain injury (n= 13; 72.2%), hemorrhagic stroke (n= 3; 16.7%), and ischemic stroke (n= 2; 11.1%). The median time to cranioplasty was 140 days (range, 51-1717 days). The median modified Rankin scale score before cranioplasty was 4 (range, 0-5). Cranioplasty was technically successful in all 18 patients. Minor postoperative complications, none related to the implant, were managed conservatively in 3 patients (16.6%), including a small intraparenchymal hematoma in 1, an extra-axial hematoma in 1, and a seizure in 1. Of these 3 patients, 1 (5.6%) died 1 week later of a suspected pulmonary embolism. No implant-related complications occurred after a median follow-up of 6 months (range, 1-38 months). All 17 survivors exhibited some degree of neurologic improvement. The cosmetic result was good or excellent for all patients. Our experience, the largest in the United States, confirms the previously reported benefits associated with the use of 3-dimensional-printed hydroxyapatite-titanium cranioplasty implants.

What is the Accuracy of PEEK Implants for Cranioplasty in Comparison to Their Patient Specific Surgical Plan?

Patient specific virtual surgical planning is a useful tool in craniofacial reconstruction. The aim of this paper is to quantify the surgical accuracy of polyetheretherketone (PEEK) cranial implant placement by comparing a computer tomography (CT)-based plan with the measured postoperative position. This is a retrospective case series. All patients who presented for evaluation and management of cranial defects at the University Health Sciences Center at San Antonio from June 2018 to July 2021 were eligible for the study. For each patient, we assessed accuracy by comparing the planned PEEK implant position, defined by a 3-dimensional mesh, to the measured postoperative position at multiple mesh vertices. The primary outcome variable in our study is the root mean square error (RMSE) between the planned position and the actual position of the implant. Twelve patients (7 men, 5 women, mean age: 25.6, median age: 30.5, range 6-74) were identified who underwent cranioplasty procedures with custom-made PEEK implants to reconstruct cranial defects. The RMSE of the vertex positions ranged between 0.66 and 3.1millimeters (mm). Eleven of the twelve patients had an RMSE less than 2mm. The Spearman rank-order correlation between the average error and the length and area of the implant were 0.59 (P=.04, significant) and 0.42 (P=.17, nonsignificant), respectively. The Pearson correlation between age and RMSE was -0.18 (P=.57), and not significant. Patient specific implant planning can design and guide the implant placement with a typical accuracy within 2mm. This level of accuracy suggests that we can place implants accurately enough to achieve good patient aesthetics. The quantitative analysis suggests that the key to accurate placement is understanding the number and spatial distribution of plates and fixation.

Late seroma and infection in patients with cranioplasty implants after lateral suboccipital craniectomy

Late wound complications, such as dehiscence or infection, are rare following the retrosigmoid approach, especially when the cranial opening is small. Here, we report two cases of late wound complications after lateral suboccipital craniectomy and cranioplasty with polymethyl methacrylate. Sudden neck rotation was the cause of complications in both cases, and seroma formation, wound dehiscence, and infection developed subsequently 4 and 19 years after surgeries, respectively.